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Doddapaneni K, Tasiran AC, Omondi F, Shah P, Mostarda L, Ever E. "Middlesex University Research Repository." core.ac.uk. 2018. Abstract76948233.pdf

Wireless Sensor Networks have seen a tremendous growth in various application areas despite prominent performance and availability challenges. One of the
common configurations to prolong the lifetime and deal with the path loss phenomena
is having a multi-hop set-up with clusters and cluster heads to relay the information.
Although researchers continue to address these challenges, the type of distributions
for arrivals at the cluster head and intermediary routing nodes is still an interesting
area of investigation. The general practice in published works is to compare an empirical exponential arrival distribution of wireless sensor networks with a theoretical
exponential distribution in a Q-Q plot diagram. In this paper, we show that such comparisons based on simple eye checks are not sufficient since, in many cases, incorrect
conclusions may be drawn from such plots. After estimating the Maximum Likelihood parameters of empirical distributions, we generate theoretical distributions
based on the estimated parameters. By conducting Kolmogorov-Smirnov test statistics for each generated inter-arrival time distributions, we find out, if it is possible to
represent the traffic into the cluster head by using theoretical distribution. Empirical
exponential arrival distribution assumption of wireless sensor networks holds only
for a few cases. There are both theoretically known such as Gamma, Log-normal
and Mixed Log-Normal of arrival distributions and theoretically unknown such as
non-Exponential and Mixed cases of arrival in wireless sensor networks. The work is
further extended to understand the effect of delay on inter-arrival time distributions
based on the type of medium access control used in wireless sensor networks.

DO Oyugi, Mavuti KM, Aloo PA, Ojuok JE, Britton JR. "Fish habitat suitability and community structure in the equatorial Lake Naivasha, Kenya." Hydrobiologia. 2014;727(1):51-63.
and DO Ogoyi, CJ Mwita EKNCOWPMS. Effect of heavy metal pollution on microalgae richness and diversity in Lake Victoria. Bujumbura, Burundi: VICRES; 2009.
DO Gisiora, Mburu S. A framework for implementation of information security management in government ministries, a case study of Ministry of Youth Affairs and Sports, Kenya. Nairobi: University of Nairobi; 2012. Abstract

Not only is Inlormation Security Strategy crucial to protect information systems, but it is central to organization survival. Ioday's organizations depend on information for their survival. Specifically, organizations depend on the systems and controls in place that provide for the ongoing confidentiality, integrity, and availability of their data and information. Many organizations are ill-equipped to define their security goals, let alone
to make an explicit connection between their security goals and the strategic drivers of
the organization. Threats to organizational information and information systems are
increasing in occurrence and in complexity and this emphasizes the urgency for
organizations to learn how to better protect their information and information systems
Information security is subjective and contextual therefore, every organization's approach
to a security strategy should be different and customized accordingly, because each
organization has its own threats, risks, business drivers, and industry compliance
requirements .
To improve the governance of IT and comply with regulatory demands, organizations are
using best practice frameworks implement information security. One of these IT
governance frameworks is COBIT (The Control Objectives for Inlormation and related
Technology). COBIT provides guidance on what could be done within an IT organization
in terms of controls, activities, measuring and documentation. This framework is however
generic and require specific knowledge in order to enable customization and use in a
local scenario.
The research methodology that was adopted was a case study. I he population of interest
was officers in the Ministry of Youth Affairs and Sports working at the headquarters.
Random sampling was used with targeted interviews to the olficers in ICT department
who are the custodians of Information systems in the ministry and the administration
which provide policy guidelines for the ministry. Data was analyzed by the use of
descriptive statistics such as frequency distribution tables, percentages, bar charts and pie
charts.
n
I he research established that the ministry faces a number of challenges in relation to
implementing information security in today's environment. In as much as the ministry’s
top officials expressed firm commitment to implementing security in the ministry, there
seemed to be no co-ordination between ministry staff and IT staff on the role of
information which indicates a communication deficit.
The key recommendations include the need for management to fully recognize that
Information Communication Technologies are a critical asset and which should be
restricted to authorized/legal use only; Information Communication Technology is a
Business Issue - not a technology issue and need to be aligned with priorities, industryprudent
practices and government regulations, and Information Communication
Technologies are enterprise-wide business with associated risks, and therefore all staff
should be involved in securing them. An implementation framework, The Control
Objectives for Government Information Technologies (COGIT) was developed which the
researcher recommended to government ministries as a reference model to Information
security management.

Do DV, Gichuhi S, Vedula SS, Hawkins BS. "Surgery for postvitrectomy cataract." Cochrane Database Syst Rev. 2018;1:CD006366. AbstractWebsite

BACKGROUND:
Cataract formation or acceleration can occur after intraocular surgery, especially following vitrectomy, a surgical technique for removing the vitreous that is used in the treatment of many disorders that affect the posterior segment of the eye. The underlying problem that led to vitrectomy may limit the benefit from removal of the cataractous lens.

OBJECTIVES:
To evaluate the effectiveness and safety of surgery versus no surgery for postvitrectomy cataract with respect to visual acuity, quality of life, and other outcomes.

SEARCH METHODS:
We searched the Cochrane Central Register of Controlled Trials (CENTRAL) (which contains the Cochrane Eyes and Vision Trials Register) (2017, Issue 5), MEDLINE Ovid (1946 to 17 May 2017), Embase.com (1947 to 17 May 2017), PubMed (1946 to 17 May 2017), Latin American and Caribbean Health Sciences Literature database (LILACS) (January 1982 to 17 May 2017), the metaRegister of Controlled Trials (mRCT) (www.controlled-trials.com); last searched May 2013, ClinicalTrials.gov (www.clinicaltrials.gov); searched 17 May 2017, and the World Health Organization (WHO) International Clinical Trials Registry Platform (ICTRP) (www.who.int/ictrp/search/en); searched 17 May 2017. We did not use any date or language restrictions in the electronic searches for trials.

SELECTION CRITERIA:
We planned to include randomized controlled trials (RCTs) and quasi-RCTs that had compared surgery versus no surgery to remove the lens from eyes of adults in which cataracts had developed following vitrectomy.

DATA COLLECTION AND ANALYSIS:
Two review authors independently screened the search results according to the standard methodological procedures expected by Cochrane.

MAIN RESULTS:
We found no RCTs or quasi-RCTs that had compared surgery versus no surgery to remove the lens from eyes of adults in which cataracts had developed following vitrectomy.

AUTHORS' CONCLUSIONS:
There is no evidence from RCTs or quasi-RCTs on which to base clinical recommendations for surgery for postvitrectomy cataract. There is a clear need for RCTs to address this evidence gap. Such trials should stratify participants by their age, the retinal disorder leading to vitrectomy, and the status of the underlying disease process in the contralateral eye. Outcomes assessed in such trials may include changes (both gains and losses) of visual acuity, quality of life, and adverse events such as posterior capsular rupture and retinal detachment. Both short-term (six-month) and long-term (one- or two-year) outcomes should be examined.
Update of Surgery for post-vitrectomy cataract. [Cochrane Database Syst Rev. 2013]

Do DV, Gichuhi S, Vedula SS, Hawkins BS. Surgery for post-vitrectomy cataract (update of 2011). Cochrane Eyes & Vision Group; 2013. Abstract

BACKGROUND:

Cataract formation or acceleration can occur after intraocular surgery, especially following vitrectomy, a surgical technique for removing the vitreous which is used in the treatment of disorders that affect the posterior segment of the eye. The underlying problem that led to vitrectomy may limit the benefit from cataract surgery.

OBJECTIVES:

The objective of this review was to evaluate the effectiveness and safety of surgery for post-vitrectomy cataract with respect to visual acuity, quality of life, and other outcomes.

SEARCH METHODS:

We searched CENTRAL (which contains the Cochrane Eyes and Vision Group Trials Register) (The Cochrane Library 2013, Issue 4), Ovid MEDLINE, Ovid MEDLINE in-Process and Other Non-Indexed Citations, Ovid MEDLINE Daily Update, Ovid OLDMEDLINE (January 1946 to May 2013), EMBASE (January 1980 to May 2013, Latin American and Caribbean Health Sciences Literature Database (LILACS) (January 1982 to May 2013), PubMed (January 1946 to May 2013), the metaRegister of Controlled Trials (mRCT) (www.controlled-trials.com), ClinicalTrials.gov (www.clinicaltrial.gov) and the WHO International Clinical Trials Registry Platform (ICTRP) (www.who.int/ictrp/search/en). We did not use any date or language restrictions in the electronic searches for trials. We last searched the electronic databases on 22 May 2013.

SELECTION CRITERIA:

We planned to include randomized and quasi-randomized controlled trials comparing cataract surgery with no surgery in adult patients who developed cataract following vitrectomy.

DATA COLLECTION AND ANALYSIS:

Two authors screened the search results independently according to the standard methodological procedures expected by The Cochrane Collaboration.

MAIN RESULTS:

We found no randomized or quasi-randomized controlled trials comparing cataract surgery with no cataract surgery for patients who developed cataracts following vitrectomy surgery.

AUTHORS' CONCLUSIONS:

There is no evidence from randomized or quasi-randomized controlled trials on which to base clinical recommendations for surgery for post-vitrectomy cataract. There is a clear need for randomized controlled trials to address this evidence gap. Such trials should stratify participants by their age, the retinal disorder leading to vitrectomy, and the status of the underlying disease process in the contralateral eye. Outcomes assessed in such trials may include gain of vision on the Early Treatment Diabetic Retinopathy Study (ETDRS) scale, quality of life, and adverse events such as posterior capsular rupture. Both short-term (six-month) and long-term (one-year or two-year) outcomes should be examined.

DO A, KA W, EAO D, chindia ML, JF O, AK L, JO G. "Nasopalatine duct cyst." African Journal of Oral Health Sciences. 2014.
Do DV. "Surgery for post-vitrectomy cataract." Cochrane Database Syst Rev. 2008 Jul 16;(3):CD006366.. 2008. AbstractWebsite

BACKGROUND: Cataract formation or acceleration can occur after intraocular
surgery, especially following vitrectomy, a surgical technique for removing the
vitreous used in the treatment of disorders that affect the posterior segment of
the eye. OBJECTIVES: The objective of this review was to evaluate benefits and
adverse outcomes of surgery for post-vitrectomy cataract with respect to visual
acuity, quality of life, and other outcomes. SEARCH STRATEGY: We searched the
Cochrane Controlled Trials Register (CENTRAL) (which contains the Cochrane Eyes
and Vision Group Trials Register) (The Cochrane Library, Issue 4, 2007), MEDLINE,
EMBASE, Latin America and Caribbean Health Sciences (LILACS) and the UK Clinical
Research Network Portfolio Database (UKCRN).The databases were last searched on
18 January 2008. We also searched www.clinicaltrials.gov,
www.controlled-trials.com, and www.actr.org.au in December 2007, in case
pertinent trials were registered and were nearing completion. SELECTION CRITERIA:
We planned to include randomized and quasi-randomized trials comparing cataract
surgery with no surgery in adult patients who developed cataract following
vitrectomy. DATA COLLECTION AND ANALYSIS: Two authors screened the search results
independently. No studies were eligible for inclusion in the review. MAIN
RESULTS: We found no randomized or quasi-randomized trials comparing cataract
surgery with no cataract surgery for patients developing cataracts following
vitrectomy surgery. AUTHORS' CONCLUSIONS: There is no evidence from randomized or
quasi-randomized controlled trials on which to base clinical recommendations for
surgery for post-vitrectomy cataract.

Do DV, Hawkins BS, Gichuhi S, Vedula SS. "Surgery for post-vitrectomy cataract (Review).". 2011. Abstract

Cataract formation or acceleration can occur after intraocular surgery, especially following vitrectomy, a surgical technique for removing the vitreous used in the treatment of disorders that affect the posterior segment of the eye.The underlying problemthat led to vitrectomy may limit benefit from cataract surgery. Objectives The objective of this review was to evaluate benefits and adverse outcomes of surgery for post-vitrectomy cataract with respect to visual acuity, quality of life, and other outcomes. Search strategy We searched CENTRAL (which contains the Cochrane Eyes and Vision Group Trials Register) (The Cochrane Library 2011, Issue 2), MEDLINE (January 1950 to April 2011), EMBASE (January 1980 to April 2011), Latin American and Caribbean Health Sciences Literature Database (LILACS) (January 1982 to April 2011), the metaRegister of Controlled Trials (mRCT) (www.controlled-trials.com), ClinicalTrials.gov (www.clinicaltrial.gov) and the Australian New Zealand Clinical Trials Registry (ANZCTR) (www.anzctr.org.au). There were no date or language restrictions in the electronic searches for trials. The electronic databases were last searched on 19 April 2011. Selection criteria We planned to include randomized and quasi-randomized trials comparing cataract surgery with no surgery in adult patients who developed cataract following vitrectomy. Data collection and analysis Two authors screened the search results independently. No studies were eligible for inclusion in the review. Main results We found no randomized or quasi-randomized trials comparing cataract surgery with no cataract surgery for patients who developed cataracts following vitrectomy surgery. There is no evidence from randomized or quasi-randomized controlled trials on which to base clinical recommendations for surgery for post-vitrectomy cataract. There is a clear need for randomized controlled trials to address this evidence gap. Such trials should stratify participants by their age, the retinal disorder leading to vitrectomy, and the status of the pathologic process in the contralateral eye. Outcomes assessed in such trials may include gain of 8 or more letters vision on the Early Treatment Diabetic Retinopathy Study (ETDRS) scale, quality of life, and adverse events such as posterior capsular rupture. Both short-term (six months) and long-term (oneyear or two-years) outcomes should be examined.

DN Kareithi, Salifu D, N Owuor, Subramanian S, Tonnang EZH. "An algorithm for data reconstruction from published articles–Application on insect life tables." Cogent Mathematics & Statistics. 2019;6(1):1701377. AbstractWebsite

Data collection in life table experiments is generally time-consuming and costly such that data reconstruction of published information provides an avenue to access the original data for purposes of further investigation. In this paper, we present an algorithm that reconstructs life table raw data using a summary of results from published articles. We present the steps of the development and implementation (in the R computer language) of the algorithm, its scope of application, assumptions, and limitations. Statistical background of the algorithm is also presented. The developed algorithm was then applied to reconstruction of life table data of two insect species, Chilo partellus and Busseola fusca, from published information. Welch’s two-sample t-test was applied to test the difference between the original and reconstructed data of the insect life stages. C. Partellus results were not significantly different, but, for B. fusca, pupa development time, and larva and pupa development rate were significantly different at the 95% confidence level. It is concluded that the algorithm could be used to reconstruct original data sets from cohort life table data sets of insects, given published information and sample sizes.

DN K, TA N, JK W, C BL. "Systemic porcine salmonellosis: A potential zoonosis and cause of mortality in small-holder pig farm in Kenya." Tanzania Veterinary Journal. 2013;28(1):8-13.
DN K, TA N, JK W, C BL. "Cases of poisoning encountered naturally in smallholder farms in Nairobi and its environs." Kenya Veterinarian. 2011;36:55-63.
DM N, M M, L K, V M, A M. "University Medical Education In Kenya: The Challenges. ." Medical Teacher.; : . 2010;32(10):812-815.
DM N, SK M, A O, VN M, AW M, LI K, DM B, D M. "Prevalence and characteristics of psychotic-like experiences in Kenyan youth.". 2012.
DM M, DM N, MM M, J B, K S, MJ G. "Environmental implications of high metal content in soils of a titanium mining zone in Kenya." Environ Sci Pollut Res. 2016;23(21):21431-21440.
DM L, SM G, P C, HM A, JM K. "Management of bovine papilomatosis using autogenous vaccine: A case study in Bukura Agricultural College Western Kenya.". In: Joint Faculty of Veterinary Medicine 8th Biennal and 46th Annual Conference of the Kenya Veterinary Association . Safari Park Nairobi; 2012.
DM K, A S, A O, A Y. "Environmental effects of selected chemical and physical geothermometers at Olkaria Geothrmal power plant." Journal of Sustainable Development. 2010;3(6):14-25. Abstractscan0015.pdfWebsite

21) S. Derese, A. Yenesew, J.O. Midiwo, Heydenreich and M.G. Peter. (). ..

DK Inoti, Mbugua PN, Gachuiri CK, Maina JG. "Physical and chemical characteristics of limestone for use in layer feeds in Kenya." Indian Journal of Animal Nutrition. 2020;37(3):242-246.
DK M, Kayizzi-Mugerwa S. "Incentive Structure and Efficiency in the Kenyan Civil Service.". In: Reforming Africa’s Institutions: Ownership, Incentives, and Capabilities. Helsinki: The United Nations University; 2003.
DK M, Mwabu G, Kimenyi MS. "Does Education Pay Dividend? Earnings and Returns to Education in Kenya.". In: Communicating Development Research Highlights.; 2004.
DK M, Bigsten A, Kimuyu P. "Wage Determination in the Kenyan Manufacturing Sector.". In: Structure and Performance of Manufacturing in Kenya. McMillan; 2002.
DK M, Sen K. "The Labor Market Effects of Globalisation in Kenya." Journal of International Development . 2004;16:29-43.
DK M, Mariara JK. "Poverty and Antipoverty Measures in Kenya.". In: Proceedings of The National Workshop on Poverty and Policy in Kenya. University of Nairobi Press; 2006.
DK M, Mutegi R, Kipruto S, Muriithi M, Oleche OM, Mwabu G, YOUNGER SD. " Inequality trends and diagnostics in Kenya," Working Paper, Kenya National Bureau of Statistics."; 2020.
DK M, Bigsten A, Mwabu G. "Trade union membership and earnings in Kenyan manufacturing firms." Applied Economics . 2005;37:1693-1704.
Djurfeldt AA, Dzanku FM, Isinika AC. "Technology Use, Gender, and Impact of Non-Farm Income on Agricultural Investment: An Empirical Analysis of Maize Production in Two Regions of Kenya.". In: Agriculture, Diversification, and Gender in Rural Africa: Longitudinal Perspectives from Six Countries. United Kingdom: Oxford University Press; 2018.
Djonov V, Makanya AN. "New insights into intussusceptive angiogenesis. In: Mechanisms of Angiogenesis.". In: Mechanisms of Angiogenesis . Vol. XIV.; 2005:.
Djonov V, Makanya A, Hlushchuk R, Baum O. Microvascular growth and remodeling: the interplay between sprouting and intussusceptive angiogenic mechanisms.. American Association of Anatomists; 2007.
Djonov V, Makanya AN. "New insights into intussusceptive angiogenesis." EXS. 2005;(94):17-33.
Djeussi DE, Sandjo LP,.Noumedem JAK, Omosa LK, Ngadjui BT, Kuete V. "Antibacterial Activities of the Methanol Extracts and Compounds from Erythrina sigmoidea against Gram-negative Multi-drug Resistant Phenotypes." BMC Complementary and Alternative Medicine. 2015;15:453.bmc_2015_djeussi_et_al._erythrina1.pdf
Dipla K, Nassis GP, Vrabas IS. "Blood {Pressure} {Control} at {Rest} and during {Exercise} in {Obese} {Children} and {Adults}." Journal of Obesity. 2012;2012:e147385. AbstractWebsite

The hemodynamic responses to exercise have been studied to a great extent over the past decades, and an exaggerated blood pressure response during an acute exercise bout has been considered as an indicator of cardiovascular risk. Obesity is a major factor influencing the blood pressure response to exercise since evidence indicates that the arterial pressure response to exercise is exacerbated in obese compared with lean adults. Signs of augmented responses (such as an exaggerated blood pressure response) to physical exertion appear early in life (from the prepubertal years) in obese individuals. Understanding the mechanisms that drive the altered hemodynamic responses during exercise in obese individuals and prevent the progression to hypertension is vitally important. This paper focuses on the evidence linking obesity with alterations of the autonomic nervous system and discusses the potential mechanisms and consequences of the altered sympathetic nervous system behavior in obese individuals at rest and during exercise. Furthermore, this paper presents the alterations in the reflex regulatory mechanisms (&\#8220;exercise pressor reflex&\#8221; and baroreflex) in obese children and adults and addresses the effects of training on obesity-related disturbances.

Dion M, Osanjo G, Andre C, others. "Identification by saturation mutagenesis of a single residue involved in the a-galactosidase AgaB regioselectivity." Glycoconjugate Journal. 2001;18:457-464.
Dinsmore CE, Daugherty S, Zeitz HJ. "Teaching and learning gross anatomy: {Dissection}, prosection, or “both of the above?”." Clinical Anatomy. 1999;12:110-114. AbstractWebsite
n/a
Ding J, Shen L, Lü Z, Peng B. "Parallel machine scheduling with completion-time-based criteria and sequence-dependent deterioration." Computers & Operations Research. 2019;103:35-45. Abstract
n/a
Dindi E, Havskov J, Iranga M, Jonathan E, Lombe DK, Mamo A, Turyomurugyendo G. "Potential capability of the East African seismic stations.". 1996. AbstractPotential capability of the East African seismic stations

It is well known that Africa is poorly covered with seismic stations and relatively few readings reach the international data bases. In September 1993 a workshop was held in Dar es Salaam, where all available seismograms for the months November and December 1992 from Ethiopia, Kenya, Uganda, Tanzania, Zambia, and Zimbabwe were analyzed. A bulletin was prepared for the 2 months of data containing 645 events of which 222 were reported as teleseisms and the rest as regional events. Seventy events had more than three stations reporting and were located within the area, mostly in central East Africa. For the same time period, PDE has five events reported in central East Africa, and it seems that the local stations can lower the detection threshold from about magnitude 4.6 to 4.0. The existing networks in East Africa thus have a large potential for increasing the quantity and quality of data available to the seismic community, and the workshop showed that it is very important to cooperate on a regional basis to achieve this.

Dindi EW. GEOPHYSICAL STUDIES OF ANZA GRABEN, NORTH EASTERN KENYA.; 1985. Abstract

ABSTRACT
Anza Graben is situated in the north and northeastern Kenya. It is about 120 km wide and approximately 600 km long. The area of the present study is located mainly in NE Kenya and constitutes a strike length of about 300 km. The graben is almost entirely sediment filled and is estimated to be of Cretaceous age. It is characterized by a prominent negative Bouguer anomaly reaching -40 mGal.

Several studies were made in an effort to determine its subsurface structure. These involved interpretation of a number of seismic reflection profiles, 3D interactive gravity modelling using fixed density contrasts between the sediment infill and the basement, and the analysis by filtering and modelling of the aeromagnetic data hover the graben. A crustal modelling of refraction data along the western shoulder of the Anza graben using 2D ray tracing was also performed.

Two major basins are recognizable from the results of the studies, namely the southern basin which has a northeasterly dip and the northern basin having a southwesterly one. This alternating asymmetry is also indicated for an adjoining smaller basin located to the west of the graben. The density contrast used for the final gravity model is -300 kg/m3 which indicates a maximum sediment thickness of about 8 km. The modelling of aeromagnetic data however favour a maximum thickness of at least 10km. A 2D refraction crustal P wave model of the western shoulder indicates that the crust thins northwestwards with the Moho depth decreasing from 35 km under Chanler's Falls to approximately under the southeastern shores of Lake Turkana. The abrupt shallowing of the Moho in the Lake Turkana area is attributed to the effects of the Kenya Rift Valley. However the gentle variation in the Moho depth along the remaining section of the shoulder of Anza Graben appears to depict a regional phenomenon also attributable to the formation of the Kenya Rift Valley. It is proposed from the study that sections of the graben shoulder are underlain by slightly denser rocks and that the crustal thinning associated with Anza Graben is not significant.

Dindi E. Review of metrics for the evaluation of the waveform technologies data products. Vienna, Austria: Internal PTS Report of the CTBTO; 1998.
Dindi EW, SWAIN CJ. " Joint three-dimensional inversion of gravity and magnetic data from Jombo Hill alkaline complex, Kenya.". 1987. Abstract

ABSTRACT

Jombo alkaline complex is the largest of the alkaline complexes in Kenya. It has been the subject of several geological and geochemical studies. However, the surface geology puts few constraints on the subsurface shape of the intrusion which we here attempt to determine by simultaneous inversion of gravity and aeromagnetic data.
The major feature of the gravity map is an elliptical high >800g.u. in amplitude centred near Jombo Hill. When the filtered magnetic map is reduced to the pole and pseudo—gravity transformed, a strikingly similar anomaly is revealed, suggesting a common source. Using an iterative |east~squares technique, joint inversion of the gravity and unfiltered magnetic data for a three—dimensional model established that both data sets can be adequately modelled by a thick slab tapering upwards from c. 29 km depth and striking approximately E—W. Only the upper c. l8 km is magnetized which we interpret as an indication of the depth to the Curie isotherm. The body is predicted to be of ultramafic composition capped by the exposed syenites and ijolites. Received March 24, 1987.

Dindi EW. "Crustal structure of the Anza graben from gravity and magnetic investigations." Tectonophysics. 1994;236:359-371. Abstract

The area of the present study constitutes the northeastern sector of the Anza graben. In this sector, the graben is about 130 km wide and is characterized by a linear negative anomaly with an amplitude about - 40 mGal. Geophysical data, mainly gravity and magnetic, were analysed quantitatively, including modelling in an effort to determine the subsurface structure of the graben. The study covered a strike length of about 320 km. The results of the modelling indicate that in the area of the study, two major basins with opposite dips exist. The northern basin dips southwestwards, the southern one northeastwards. The density contrast assigned to the sediments in the final gravity model is —300 kg /m3, suggesting a maximum sediment thickness of about 8 km. The modelling of the magnetic data, however, favours a maximum thickness of over 10 km. It is proposed that intrusives occur at some depth below sections of the graben shoulders and that the graben has a gentle northwesterly regional plunge.

Dindi EW. Suggested guidelines for the NDC Evaluation of the first System-Wide Performance Test (SPT1).. Vienna, Austria: Internal PTS Report of the CTBTO; 2005.
Dindi EW, J.J. M. "Geological and geophysical characteristics of massive sulphide deposits: A case study of the Lirhanda massive sulphide deposit of Western Kenya." Journal of African Earth Sciences. 2016;120:89-101. AbstractWebsite

An integrated geophysical ground survey was conducted on an airborne electromagnetic (EM) anomaly located in Kakamega forest of Western Kenya. The purpose of the study was to establish the existence of massive sulphides and identify suitable optimal geophysical method(s) for the investigation of similar anomalies. The study was also expected to provide information on the geological and geophysical characteristics of the deposit.

Field work involved electromagnetic methods: Vertical Loop (VLEM), Horizontal Loop (HLEM), TURAM EM and potential field methods: gravity and magnetics. Geochemical sampling was carried out concurrently with the geophysical survey.

All the geophysical methods used yielded good responses. Several conductors conforming to the strike of the geology were identified. TURAM EM provided a higher resolution of the conductors compared to VLEM and HLEM. The conductors were found to be associated with positive gravity anomalies supporting the presence of bodies of higher density than the horst rock. Only the western section (west of 625W) of the grid is associated with strong magnetic anomalies. East of 625W strong EM and gravity anomalies persist but magnetic anomalies are weak. This may reflect variation in the mineral composition of the conductors from magnetic to non-magnetic. Geochemical data indicates strong copper anomalies (upto 300 ppm) over sections of the grid and relatively strong zinc (upto 200 ppm) and lead (upto 100 ppm) anomalies. There is a positive correlation between the location of the conductors as predicted by TURAM EM and the copper and zinc anomalies.

A test drill hole proposed on the basis of the geophysical results of this study struck massive sulphides at a depth of 30m still within the weathered rock zone. Unfortunately, the drilling was stopped before the sulphides could be penetrated. The drill core revealed massive sulphide rich in pyrite and pyrrhotite.

An attempt has been made to compare characteristics of the Lirhanda massive sulphide deposit with those of better documented massive sulphides. Despite the fact that very little is known about Lirhanda, there are several similarities on the characteristics compared. These include evidence of back arc regional environment, calc-alkaline volcanic associations, conformity of anomalies to the structural trend of the host rock, proximity of synvolcanic rift, dispersive anomalies of copper and zinc in soils, presence of gossan and association of the deposit with strong EM anomalies.

Dindi EW. A GRAVITY SURVEY OF THE JOMBO HILL AREA, SOUTH COAST KENYA. Nairobi: University of Nairobi; 1982. Abstract

ABSTRACT

The aeromagnetic survey of the Jombo Hill Area conducted in l977 revealed an anomaly of 2000 gammas in amplitude in the area of the intrusive rocks. This value gtands,out as one of the highest values ever recorded in Kenya. In order to investigate the anomaly further, a gravity survey was conducted in the area within 40 km radius_of Jombo hill. After the necessary corrections to the observed data they were compiled into a Bouguer gravity map of the area.

The Bouguer gravity anomalies range from - 40 to over 50 mgals. The peak of the anomaly occurs immediately to the south of the hill and most of the contours close on this peak. It is noticeable that the magnetic and gravity anomalies are roughly coincident. The relative ease and convenience of gravity 3D modelling relative to magnetic 3D modelling, in the context of this study, dictated the placing of a greater emphasis on the former in the quantitative interpretation.
The gravity anomaly is interpreted in terms of an inverted funnel like body of density 3.1 gcm-3, with its top surface at about l km depth. Estimates from the magnetic map yield a similar value for the depth to the top of the body.

Most of the magnetization in these rocks is the induced type and is in the direction of the ambient field. The large grain size has an appreciable effect on the magnetization in these rocks.
It appears from the study, that both the magnetic and gravity anomalies are caused by a single body. The gravity anomaly depicts the effect of the entire body while the magnetic anomaly that due to a relatively small central and shallow portion of it. The exact geometry of this portion was not determined. However a sphere fitted to the anomaly gave satisfactory results.

By comparison with the geology of the area and with the characteristics of other known alkaline complexes in Eastern Africa, the gravity model is considered geologically reasonable.

Dindi E, Havskov J, Iranga M, Jonathan E, Lombe DK, Mamo A, Turyomurugyendo G. "Potential Capability of the East African Seismic Stations." Bulletin of the Seismological Society of America. 1995;85(1):354-360. Abstract

It is well known that Africa is poorly covered with seismic stations and relatively few readings reach the international data bases. In September I993 a workshop was held in Dar es Salaam, where all available seismograms for the months November and December 1992 from Ethiopia, Kenya, Uganda, Tanzania, Zambia, and Zimbabwe were analyzed. A bulletin was prepared for the 2 months of data containing 645 events of which 222 were reported as teleseisms and the rest as regional events. Seventy events had more than three stations reporting and were located within the area, mostly in central East Africa.
For the same time period, PDE has five events reported in central East Africa, and it seems that the local stations can lower the detection threshold from about magnitude 4.6 to 4.0. The existing networks in East Africa thus have a large potential for increasing the quantity and quality of data available to the seismic community, and the workshop showed that it is very important to cooperate on a regional basis to achieve this.

Dindi E. "An assessment of the performance of the geophysical methods as a tool for the detection of zones of potential subsidence in the area southwest of Nakuru town, Kenya." Environmental Earth Sciences. 2015;73(7):3643-3653. AbstractWebsite

The area to the southwest of Nakuru town in Kenya located within the Kenya Rift Valley is prone to incidences of ground subsidence especially toward the end of the heavy rain season. The zones affected by subsidence are typically linear, trending approximately north–south conforming to the structural trend of the Kenya Rift Valley. These ground subsidence incidences have in the past led to collapse of houses and damage to roads that happen to be located above the affected linear zones. This study set out to investigate the potential of geophysical methods to delineate these linear zones. Two profiles of lengths 2,430 and 2,850 m, respectively, were selected for this purpose. The study was conducted immediately after one major incidence of subsidence when the zones affected were still fresh and observable. Magnetics, very low-frequency electromagnetics (VLF-EM), and gravity methods were used in the study. The choice of these methods was dictated by their widely known applicability in the detection of linear structures, especially faults. The results of the study have shown that the linear zones affected yield good response to magnetic and VLF-EM methods. Anomalies similar to those detected across fresh subsidence zones were also detected at locations where there was no surface expression of subsidence, suggesting that the latter locations are potential zones of future subsidence. Further, there were locations along the profile that were without any anomalies. The relatively low sensitivity of the zones to the gravity method is attributed to the very narrow nature of these zone and hence limited low-density material to generate appreciable negative gravity anomalies. It is concluded from this study that geophysics permits identifying the potential areas to develop surficial collapse and to identify sectors that are potentially dangerous because they present similar signatures as the sectors with surficial evidence and sectors without anomalies. The sectors without anomalies are interpreted as having a different subsoil structure to that with sinkholes.

DIN DRMUJAHIDFEROZE. "Editorial on .". In: M.Med Thesis 1991. Philosophical Issues Invoked by Shona People; 2005. Abstract
OBJECTIVES: To estimate the prevalence of active trachoma (TF) in children aged one to nine years and potentially blinding trachoma (TT) in adults aged 15 years and older in six known trachoma-endemic districts in Kenya. DESIGN: Community based survey. SETTING: Six known trachoma endemic districts in Kenya (Samburu, Narok, West Pokot, Kajiado Baringo and Meru North). SUBJECTS: A total of 6,982 children aged one to nine years and 8,045 adults aged 15 years and older were randomly selected in a two stage random cluster sampling method: Twenty sub-locations (clusters) per district and three villages per sub-location were randomly selected. Eligible children and adults were enumerated and examined for signs of trachoma. RESULTS: Blinding trachoma was found to be a public health problem in all the surveyed districts. Active trachoma was a district wide public health problem in four districts (Samburu, Narok, West Pokot and Kajiado) and only in some of the sub-locations of the other two (Baringo and Meru North). CONCLUSIONS: There is need for district trachoma control programmes preferably using the WHO recommended SAFE strategy in all the surveyed districts. Extrapolation of these survey results to the entire country could not be justified. There is need to survey the remaining 12 suspected endemic districts in Kenya.
Dimova I, Hlushchuk R, A M, Buergy R, Le Noble F, Djonov V. Modulation of angiogenesis by Notch-signalling inhibition in the chick area vasculosa.. Interlaken, Switzerland; 2009.
Dimova I, Karthik S, Makanya A, Hlushchuk R, Semela D, Volarevic V, Djonov V. "SDF-1/CXCR4 signalling is involved in blood vessel growth and remodelling by intussusception." J. Cell. Mol. Med.. 2019;23(6):3916-3926. Abstract

The precise mechanisms of SDF-1 (CXCL12) in angiogenesis are not fully elucidated. Recently, we showed that Notch inhibition induces extensive intussusceptive angiogenesis by recruitment of mononuclear cells and it was associated with increased levels of SDF-1 and CXCR4. In the current study, we demonstrated SDF-1 expression in liver sinusoidal vessels of Notch1 knockout mice with regenerative hyperplasia by means of intussusception, but we did not detect any SDF-1 expression in wild-type mice with normal liver vessel structure. In addition, pharmacological inhibition of SDF-1/CXCR4 signalling by AMD3100 perturbs intussusceptive vascular growth and abolishes mononuclear cell recruitment in the chicken area vasculosa. In contrast, treatment with recombinant SDF-1 protein increased microvascular density by 34% through augmentation of pillar number compared to controls. The number of extravasating mononuclear cells was four times higher after SDF-1 application and two times less after blocking this pathway. Bone marrow-derived mononuclear cells (BMDC) were recruited to vessels in response to elevated expression of SDF-1 in endothelial cells. They participated in formation and stabilization of pillars. The current study is the first report to implicate SDF-1/CXCR4 signalling in intussusceptive angiogenesis and further highlights the stabilizing role of BMDC in the formation of pillars during vascular remodelling.

Dimova I, Hlushchuk R, Makanya A, Styp-Rekowska B, Ceausu A, Flueckiger S, Lang S, Semela D, Le Noble F, Chatterjee S, Djonov V. "Inhibition of Notch signaling induces extensive intussusceptive neo-angiogenesis by recruitment of mononuclear cells." Angiogenesis. 2013;16(4):921-37. Abstract

Notch is an intercellular signaling pathway related mainly to sprouting neo-angiogenesis. The objective of our study was to evaluate the angiogenic mechanisms involved in the vascular augmentation (sprouting/intussusception) after Notch inhibition within perfused vascular beds using the chick area vasculosa and MxCreNotch1(lox/lox) mice. In vivo monitoring combined with morphological investigations demonstrated that inhibition of Notch signaling within perfused vascular beds remarkably induced intussusceptive angiogenesis (IA) with resultant dense immature capillary plexuses. The latter were characterized by 40 % increase in vascular density, pericyte detachment, enhanced vessel permeability, as well as recruitment and extravasation of mononuclear cells into the incipient transluminal pillars (quintessence of IA). Combination of Notch inhibition with injection of bone marrow-derived mononuclear cells dramatically enhanced IA with 80 % increase in vascular density and pillar number augmentation by 420 %. Additionally, there was down-regulation of ephrinB2 mRNA levels consequent to Notch inhibition. Inhibition of ephrinB2 or EphB4 signaling induced some pericyte detachment and resulted in up-regulation of VEGFRs but with neither an angiogenic response nor recruitment of mononuclear cells. Notably, Tie-2 receptor was down-regulated, and the chemotactic factors SDF-1/CXCR4 were up-regulated only due to the Notch inhibition. Disruption of Notch signaling at the fronts of developing vessels generally results in massive sprouting. On the contrary, in the already existing vascular beds, down-regulation of Notch signaling triggered rapid augmentation of the vasculature predominantly by IA. Notch inhibition disturbed vessel stability and led to pericyte detachment followed by extravasation of mononuclear cells. The mononuclear cells contributed to formation of transluminal pillars with sustained IA resulting in a dense vascular plexus without concomitant vascular remodeling and maturation.

Dimova I, Hlushchuk R, Makanya A, Karthik S, Nikolova D, Djonov V. Notch signaling in normal and tumor angiogenesis. Metropolitan Hotel, Athens, Greece; 2015.
Dimbuson. WB, Bedno. SA, Martin. S. Description of a Distinct Antigenic Drift Variant of Influenza A (H3N2) Circulating in Nairobi, Kenya. Toronto, Ontario, Canada: MediTech Media Conferencing, Inc. Atlanta, GA 30328; 2007. Abstract
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Dimba E, Aden A, Ndolo U, Chindia ML. "Socio-Economic effects of Khat (Catha edulis) chewing.". 2006. Abstract
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Dimba, Njiru W, Gathece LW, Mutave RJ, Ogwell A. "Tobacco cessation through use of oral health care providers in Kenya.". In: Global Tobacco Treatment Summit . Mayo Clinic Nicotine Dependence ; 2016.
Dimba E, Chindia ML, Ngovo C, Patel S, Muriithi MW. "Neural tumours of the neck and craniofacial region.". In: JOURNAL OF DENTAL RESEARCH. Vol. 78. AMER ASSOC DENTAL RESEARCH 1619 DUKE ST, ALEXANDRIA, VA 22314 USA; 1999:. Abstract
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Dimba EA, Chindia ML, Nyanchoka INI, Macigo FGI, others. "The Oral and Dental effects of Khat chewing in the Eastleigh area of Nairobi.". 2008. Abstract
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Dimba EAO, F.G. M, IN N, P W, Chindia ML. "oral and dental effects of khat chewing in the Eastleigh area of Nairobi.". 2008.
Dimba E. "Khat and Oral Cancer.". 2002. Abstract
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Dimba E. "Khat and Oral Cancer.". 2002.
Dimba EAO, Gichana J, Limo AK, Wakoli KA, Chindia ML, Awange DO. "An audit of oral diseases at a Nairobi centre, 2000–2004." International dental journal. 2007;57:439-444. Abstract
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Dimba EAO, Newa F, Macharia J, Nyanumba MD. "Determinants of acceptance of eHealth technology by Health Care Practitioners in Nairobi, Kenya." East African Medical Journal. 2022;99:4450-4460. Abstract
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Dimba E, Njiru W, Gathece LW, Mutave RJ, Ogwell A. "Tobacco cessation through use of oral health care providers in Kenya.". In: 16th World Conference on Tobacco or Health. Abu Dhabi, UAE; 2015.
Dimba EA, Moshy J, Limo A, Otwoma JG, Guthua Symon W. "Synchronous Occurrence of Ossifying Fibroma of the Mandible and Maxilla: A Case Report.". 2008. Abstract
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Dimba EAO, Yengopal V, Joshua E, Thavarajah R, Balasundaram S. "Access and management of HIV-related diseases in resource-constrained settings: a workshop report." Oral diseases. 2016;22:206-210. Abstract
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Dimba EAO. "Plan of radiotherapy management of head and neck cancer." East African Medical Journal. 2009;86. Abstract
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Dimba EAO, Guthua SW. "25. Oral Squamous Cell Carcinoma." NATIONAL GUIDELINES FOR CANCER MANAGEMENT KENYA. 2013:144. Abstract
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Dimba E, Gjertsen BT, Francis GW, Johannessen AC, Vintermyr OK. "Catha edulis (Khat) induces cell death by apoptosis in leukemia cell lines." Annals of the New York Academy of Sciences. 2003;1010:384-388. Abstract
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Dimba EAO, Guthua SW, Chindia ML. Oral Cancer In Kenya. In Solid Tissue Tumours Handbook.. University of Nairobi; 2006. Abstract
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Dimba EA, Moshy J, Limo A, Otwoma JG, others. "Synchronous Occurrence of Ossifying Fibroma of the Mandible and Maxilla.". 2008. Abstract
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Dimba E;, Chindia ML;, Ikito A;, Butt FMA. "Ipsilateral Synchronous Manifestation of an Hiv-Infection Associated Plunging Ranula and Sublingual Salivary Gland Sialocoele: A Review and Case Report.". 2013. Abstract

Plunging ranula is a rare lesion and even more in HIV-infected patients. There has been only one case documented in a 15-year old that had the vertical form HIV-infection. We report a plunging ranula occurring simultaneously with a sublingual salivary gland sialocoele as two separate lesions in an HIV-infected female patient.

Dimba EAO, Gjertsen BT, Bredholt T, Fossan KO, Costea DE, Francis GW, Johannessen AC, Vintermyr OK. "Khat (Catha edulis)-induced apoptosis is inhibited by antagonists of caspase-1 and-8 in human leukaemia cells." British Journal of Cancer. 2004;91:1726-1734. Abstract
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Dimba E. "Retinoblastoma.". 2013. Abstract
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Dimaras H, Dimba EA WGKWJK. "Digital cancer pathology in Africa." Lancet Oncol.. 2013;14(8):289-290.
Dimaras H, Kimani K, Dimba EAO, Gronsdahl P, White A, Chan HSL, Gallie BL. "Retinoblastoma." The Lancet. 2012;379:1436-1446. Abstract
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Dimaras H, Dimba EAO, Waweru W, Githanga J, Kimani K. "Digital cancer pathology in Africa." The Lancet Oncology. 2013;14:e289-e290. Abstract
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Dimaras H, Kimani K, Dimba EA, Gronsdahl P, White A, Chan HSL, Gallie BL. "Retinoblastoma." Lancet. 2012;379:1436-1446.
Dimaras H, Kimani K, Dimba E. "Aet al." Lancet. 2012;379:1436-1446. Abstract
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Dimaras H, Dimba EAO, Gallie BL. Challenging the global retinoblastoma survival disparity through a collaborative research effort. Vol. 94. BMJ Publishing Group Ltd; 2010. Abstract
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Dillon R. "Towards the definition of a framework and grammar for game analysis and design.". 2014. Abstractfull text link

The present paper defines an original approach to game analysis and design able to
characterize a given game in a simple, yet efficient, way. Inspired by models widely used
across the gaming industry, the proposed framework named AGE is built by defining and
layering different concepts: core player Actions, resulting Game-play and emotional
Experience of players. These are all linked to each other by the game's own rules and goals
to form a cohesive unit that can help in exposing the inner workings of any game. The …

Digolo P.O., Magoha G.O., Origa J, Odundo P, Nyandega I. The Effects of Massification on Higher Education in Africa. Accra, Ghana: Association of African Universities; 2008.
and Digolo, P.O.O. MOMGMJOS. "Effects of Constructivist And Conventional Methods of Instruction on Learning Biology Amongst Secondary School Students in Kenya." Journal of International Institute for Science, Technology and Education (IISTE).. 2014.
and Digolo, P.O.O. KNMWGBNS. "Effect of Computer Based Instruction on Learner Performance in art and Design in Public secondary Schools in Kenya." The International Journal of Humanities & Social Studies, . 2017;5(6):99-103.
Digolo OO. "Study of the Suggested Needs of Learners in Upper Primary Education in Kenya. ." Kenya Journal of Education. 1984;1(1):69-89.
Digolo OO. "Pedagogical issues in education.". 2002.
Digolo OO. "Pedagogical Issues in Education in Kenya." The Fountain, Journal of the Faculty of Education, University of Nairobi. 2009;(3):81-95.
Digolo OO. "Introduction to Curriculum Making Process.". In: Academic Staff Training in Curriculum Development. Embu; 2016.
Digolo PO, Inyega JO, Inyega HN. "University academics re-examine their pedagogical and people-skills: insights from capacity-building in-service programme in Kenya. The Fountain: Journal of Educational Research." The Fountain: Journal of Educational Research. 2011;V(1):97-115. Abstract

Students intellectual, social and human development is enhanced if lecturers are equipped with appropriate pedagogical and people-skills. Insights gained from lecturers capacity-building in-service training programs in a public university in Kenya are presented in this paper. Twenty thematic areas were covered aimed at improving competences of lecturers in facilitating students' learning. In-service lecturers' responses were analyzed qualitatively. In-service lecturers have training expectations and challenges in teaching university students when preparing them to become responsible citizens. They are generally satisfied with focused professional development seminars they attend, and are likely to provide effective lecturing and improved classroom practices in their faculties.

and Digolo, P.O.O. MMDNJK. "The Relationship Between the Environment and Primary School readiness in Nairobi County: The Case of Pre-School Pupils." African Journal of Education and Technology. 2016;6(1):32-38.
Digolo OO(. "Education as a process of democratization in Africa. .". In: Pan-African Colloquium; Educational innovation in Post-Colonial Africa; . University of Cape Town, South Africa.; 2014.
Digolo, P.O. IIJOHN. "Insights from capacity-building inservice program in Kenya." The Fountain: Journal of Educational Research, School of Education, University of Nairobi publication . 2011.
Dieterlen, F. KPJ, Oguge N. "Dendromus insignis." 2006 IUCN Red List of Threatened Species; 2006. Abstract
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Diener; Slyker J, Christine G, Dalton W, Lara C, Tapia KA, Richardson BA, Farquhar C, Overbaugh J, Elizabeth M-O, John-Stewart G. "Performance Of The Integrated Management Of Childhood Illness Algorithm For Diagnosis Of Hiv-1 Infection Among African Infants.". 2012.
Diener LC, Slyker JA GC, Tapia KA, Richardson BA, Wamalwa D, Farquhar C, Overbaugh J, Maleche-Obimbo E, G. J-S. "Performance of the integrated management of childhood illness algorithm for diagnosis of HIV-1 infection among African infants. ." AIDS. 2012 Sep 24;26(15):1935-41. . 2012. Abstract

Abstract
OBJECTIVES:
Early infant HIV-1 diagnosis and treatment substantially improve survival. Where virologic HIV-1 testing is unavailable, integrated management of childhood illness (IMCI) clinical algorithms may be used for infant HIV-1 screening. We evaluated the performance of the 2008 WHO IMCI HIV algorithm in a cohort of HIV-exposed Kenyan infants.
METHODS:
From 1999 to 2003, 444 infants had monthly clinical assessments and quarterly virologic HIV-1 testing. Using archived clinical data, IMCI sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) were calculated using virologic testing as a gold standard. Linear regression and survival analyses were used to determine the effect of age on IMCI performance and timing of diagnosis.
RESULTS:
Overall IMCI sensitivity, specificity, PPV, and NPV value were 58, 87, 52, and 90%, respectively. Sensitivity (1.4%) and PPV (14%) were lowest at 1 month of age, when 81% of HIV infections already had occurred. Sensitivity increased with age (P < 0.0001), but remained low throughout infancy (range 1.4-35%). Specificity (range 97-100%) was high at each time point and was not associated with age. Fifty-eight percent of HIV-1-infected infants (50 of 86) were eventually diagnosed by IMCI, and use of IMCI was estimated to delay diagnosis in HIV-infected infants by a median of 5.9 months (P < 0.0001).
CONCLUSION:
IMCI had low sensitivity during the first month of life, when the majority of HIV-1 infections had already occurred and initiation of treatment is most critical. Although sensitivity increased with age, the substantial delay in HIV-1 diagnosis using IMCI limits its utility in early infant HIV-1 diagnosis.

Diener LC, Slyker JA, Christine Gichuhi, Dalton Wamalwa, Tapia KA, Richardson BA, Dalton Wamalwa, Farquhar C, Overbaugh J, Maleche-Obimbo E, John-Stewart G. "Performance of the integrated management of childhood illness algorithm for diagnosis of HIV-1 infection among African infants." AIDS. 2012;26(15):1935-41. Abstract

Early infant HIV-1 diagnosis and treatment substantially improve survival. Where virologic HIV-1 testing is unavailable, integrated management of childhood illness (IMCI) clinical algorithms may be used for infant HIV-1 screening. We evaluated the performance of the 2008 WHO IMCI HIV algorithm in a cohort of HIV-exposed Kenyan infants.

Dickson B;D, Pearl FB;, Gang G-Y;, Kahinju S;, Wandibba S. "Site reconnaissance in the Kipsing and Tol River watersheds of Central Kenya: Implications for Middle and Later Stone Age land-use patterns .". 2004. AbstractWebsite

Two seasons of archaeological site reconnaissance and geo-archaeological fieldwork in the Kipsing and Tol river valleys of central Kenya have resulted in (1) the location of 58 surface sites and 13 spot finds and (2) the excavation and dating of 11 alluvial stratigraphic profiles. These data are incorporated with our previous work in the study area to yield a preliminary interpretation of Middle and Later Stone Age tool technologies and land-use strategies during the Late Pleistocene period there. Specifically, the nature of the lithic inventories and observed distribution of archaeological sites suggests that people in the Middle Stone Age employed a “patch choice” resource and land-use strategy while those in the subsequent Later Stone Age period utilized a “logistical” strategy

Diaz CM;, Massawe SC;, Clemence A;, Gitau GK;, Kiara HK;, Muraguri GR;, O'Callaghan CJ;, Perry BD. "Risk mapping of East Coast fever in coastal and highland regions of Kenya based on predicted mortality and morbidity incidences."; 2003. Abstract

This paper proposes risk mapping as a tool for interpolating epidemiological data from intensively surveyed local sites to make conclusions over a larger area. Two ECF risk models were built using morbidity and mortality incidence data from the coastal and the central highlands of Kenya as dependent variables. It is concluded that the available data were not adequate to predict accurately mortality and morbidity of ECF. The main problem with the approach was its inability to capture the biophysical variability when the original data were distributed into grid-cells for spatial analysis.

Diaz W, G.N K. "Effect of Shubbhodaya Mycorrhiza on crop performace, draught tolerance and yields.". In: The 27th Soil Science Society of East Africa and 6th Africa Soil Science Society Conference. Hotel Cathy, Nakuru, Kenya; 2013.
Díaz D, Gómez C, Muñoz-Castañeda R, Baltanás F, Alonso JR, Weruaga E. "The olfactory system as a puzzle: playing with its pieces." Anatomical record (Hoboken, N.J.: 2007). 2013;296:1383-1400. Abstract

The mammalian olfactory bulb (OB) has all the features of a whole mammalian brain but in a more reduced space: neuronal lamination, sensory inputs, afferences, or efferences to other centers of the central nervous system, or a contribution of new neural elements. Therefore, it is widely considered as "a brain inside the brain." Although this rostral region has the same origin and general layering as the other cerebral cortices, some distinctive features make it very profitable in experimentation in neurobiology: the sensory inputs are driven directly on its surface, the main output can be accessed anatomically, and new elements appear in it throughout adult life. These three morphological characteristics have been manipulated to analyze further the response of the whole OB. The present review offers a general outlook into the consequences of such experimentation in the anatomy, connectivity and neurochemistry of the OB after (a) sensory deprivation, mainly by naris occlusion; (b) olfactory deinnervation by means of olfactory epithelium damage, olfactory nerve interruption, or even olfactory tract disruption; (c) the removal of the principal neurons of the OB; and (d) management of the arrival of newborn interneurons from the rostral migratory stream. These experiments were performed using surgical or chemical methods, but also by means of the analysis of genetic models, some of whose olfactory components are missing, colorless or mismatching within the wild-type scenario of odor processing.

Di Ferrante N, Leachman RD, Angelini P, Donnelly PV, Francis G, Almazan A, Segni G, Franzblau C, Jordan RE. "Ehlers-Danlos type V (X-linked form): a lysyl oxidase deficiency." Birth Defects Orig. Artic. Ser.. 1975;11(6):31-7.
Dharmadhikary, V. Mutua FM. "Radiating Slots in a Thick Conducting Broad Wall of a Rectangular Waveguide.". In: National Conference on Broadband Communication Systems . Pune(India); 2006.
DHARMADHIKARY VM, KONDITI DBO, KOECH EK, MAKICHE JK. "Combined Field Integral formulation for Broadwall Radiating Slots of arbitrary Shape.". In: IEEE-Africon 2009. Safari Park Hotel, Nairobi; 2009.
DHARMADHIKARY VM, KONDITI DBO, ABSALOMS HO, ADIKA CO, KOECH EK. "Practical and Thoretical Evaluation of EMC/EMI Problems of Metallic Enclosures with Apertures." IJTPE. 2010;ISSN(JULY 2010):2077-3528.
DHARMADHIKARY VM. "Technological_Curriculum & culture.". In: JSPM Pune. Kioko UM; 2008.
Dharmadhikary VM. Analysis of microstrip-patch antennas incorporating arbitrarily-shaped apertures.; 2012. Abstract

Microstrip antennas have received extensive attention as they have many attractive features, such as lightweight, small size, low profile and ease of fabrication. One of the inherent limitations when using these antennas is their limited bandwidth. Aperture coupling has proven to be a reliable and a robust feeding technique for these antennas as they are suitable for wide-bandwidth designs. A microstrip patch antenna that is coupled to a Microstrip-line by an aperture in the intervening ground plane has been designed and implemented in this work. Arbitrarily shaped coupling slots have been considered by investigating their contributing effect on the radiation characteristics of the antenna. Aperture shape and size are the crucial parameters that are considered for the aperture-coupled microstrip antennas. Our publications [109-110] have been based on a hybrid formulation combining the Method of Moments (MOM) and the Finite Difference Time Domain method (FDTD) for which, as a student, I take credit. It should also be taken as a contribution that the ingenuity of interfacing one kind of basis functions, Rao- Glitton-Wilson (RWG) for the surface with another type, the volume function for FDTD for the cavity. The aim of this work was to look for an aperture shape that gives significantly improved coupling of the radiated power from the feed-line to the resonant patch element and at the same time giving lower back-lobe radiation level from the slot. Rectangular, Circular, Bowtie and H-shaped apertures were of Micros investigated and it was found that the H-shaped aperture coupled antennas provide higher coupling and reduced backward radiation levels as compared to the other aperture shapes. The numerical analysis carried out employed the Electric Field Integral Equation technique with the Moment Method using the software called FEKOᆴ, which employs the triangular patch modelling scheme as the basis function. The antenna characteristics such as the radiation pattern, S-parameters, and input impedance were simulated for the various shapes of coupling apertures. The antenna prototypes utilizing each of these aperture shapes were constructed and tested in the laboratory and the experimental results compared with the simulated ones. The obtained results were found to be in good correlation.

Dharani N, JM O, DM M. "The Distribution of Cu and Pb Levels in soils and Acacia xanthoploea Benth. From Lake Nakuru National Park Kenya." Bulletin Environmental Contamination and Toxicology. 2007;79(2):172-177.
Dharani N, Kinyamario JI, JM O. "Structure and Composition of Acacia xanthophloea woodland in Lake Nakuru National Park, Kenya." Africa Journal of Ecology . 2006;44(4):523-530.
Dharani N, Onyari JM, Kinyamario JI, Maina, Mavuti. "Distribution of Cd and Zn levels in Soils and Acacia xanthophloea Benth. From Lake Nakuru National Park, Kenya." Bulletin of Environmental Contamination and Toxicology. 2010;85(3):318-323.
Dharani N, Kinyamario JI, Wagacha PW, Rodrigues AJ. "Browsing impact of large herbivores on Acacia xanthophloea Benth in Lake Nakuru National Park, Kenya." Africa Journal of Ecology. 2008;47(2):184-191.
Dhandapani S, Ogot MM, others. "Modeling of a leg system to illustrate the feasibility of energy recovery in walking machines.". In: Proc. of 1994 ASME Design Technical Conference.; 1994:. Abstract
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Dhananjaya G, Ndinya-Achola JO, Nsanze H. "Urine as a transport medium for Neisseria gonorrhoeae.". 1984.
Dhakal S, Cui Y, Koirala D, Ghimire C, Kushwaha S, Yu Z, Yangyuoru PM, Mao H. "Structural and mechanical properties of individual human telomeric G-quadruplexes in molecularly crowded solutions." Nucleic acids research. 2013;41(6):3915-3923.
Dews PB, Wiesel TN. "Consequences of monocular deprivation on visual behaviour in kittens." The Journal of physiology. 1970;206:437-455. Abstract

1. Kittens were raised for a period with one of their eyes closed by suture of the lids. The age at suture and the duration of deprivation were varied systematically. When the cat was a year or more old, the normal and deprived eyes were compared using behavioural procedures which made graded demands on visual function.2. In kittens deprived from birth, the duration of eye closure determined the severity of the defect in vision with the deprived eye. A cat with an eye closed for the first 4-6 weeks showed as a permanent effect only a lowering of the visual acuity. When closure was extended through the first 7 weeks the visual acuity was further lowered but the animal still showed good visual guidance of paw placement. Further extension of deprivation through the first 16 weeks led to a still more severe defect; such animals showed no indication of visual guidance of paw placement or of pattern discrimination. They were influenced visually by stimuli that differed in luminosity.3. The upper age limit of the susceptibility to deprivation was determined by varying the age at eye closure. Waiting until 1 month of age before closing the eye conferred no appreciable protection. Waiting until 2 months of age, however, reduced the damage. Deprivation starting at 4 months of age or later produced no effect we could detect. Thus, susceptibility is greatest during the second month after birth and then falls until by 4 months of age the kitten, like the adult cat, suffers no permanent consequences of monocular light and form deprivation.4. After exclusive use of the deprived eye for a period, brought about by closure of the normal eye, visual control with the deprived eye was better than in similarly deprived cats whose normal eye was never closed. Improvement in the deprived eye was also seen in an animal whose normal eye was closed after both eyes had been open for more than one year.5. Relating the behavioural results to the neurophysiological findings in the visual cortex in the same or similarly deprived cats shows that the grading of visual defects with age and length of deprivation was generally paralleled by a change in proportion of cortical cells driven by stimulation of the deprived eye. The effect of reversal of eye closure in improving behavioural control was not, however, accompanied by an increase in the ability of the deprived eye to drive cortical cells.

Dews PB, Wiesel TN. "Consequences of monocular deprivation on visual behaviour in kittens." The Journal of Physiology. 1970;206:437-455. AbstractWebsite

1. Kittens were raised for a period with one of their eyes closed by suture of the lids. The age at suture and the duration of deprivation were varied systematically. When the cat was a year or more old, the normal and deprived eyes were compared using behavioural procedures which made graded demands on visual function., 2. In kittens deprived from birth, the duration of eye closure determined the severity of the defect in vision with the deprived eye. A cat with an eye closed for the first 4-6 weeks showed as a permanent effect only a lowering of the visual acuity. When closure was extended through the first 7 weeks the visual acuity was further lowered but the animal still showed good visual guidance of paw placement. Further extension of deprivation through the first 16 weeks led to a still more severe defect; such animals showed no indication of visual guidance of paw placement or of pattern discrimination. They were influenced visually by stimuli that differed in luminosity., 3. The upper age limit of the susceptibility to deprivation was determined by varying the age at eye closure. Waiting until 1 month of age before closing the eye conferred no appreciable protection. Waiting until 2 months of age, however, reduced the damage. Deprivation starting at 4 months of age or later produced no effect we could detect. Thus, susceptibility is greatest during the second month after birth and then falls until by 4 months of age the kitten, like the adult cat, suffers no permanent consequences of monocular light and form deprivation., 4. After exclusive use of the deprived eye for a period, brought about by closure of the normal eye, visual control with the deprived eye was better than in similarly deprived cats whose normal eye was never closed. Improvement in the deprived eye was also seen in an animal whose normal eye was closed after both eyes had been open for more than one year., 5. Relating the behavioural results to the neurophysiological findings in the visual cortex in the same or similarly deprived cats shows that the grading of visual defects with age and length of deprivation was generally paralleled by a change in proportion of cortical cells driven by stimulation of the deprived eye. The effect of reversal of eye closure in improving behavioural control was not, however, accompanied by an increase in the ability of the deprived eye to drive cortical cells.

Dessie, T; Gebreyesus G;, Mekuria G;, Jembere T;, Woldu T;, Agaba M;, Mwai OA. "Harnessing genetic diversity to improve goat productivity in Africa: Ethiopia component."; 2013.
Desjardins M, Thompson CE, Filion LG, Ndinya-Achola JO, Plummer FA, Ronald AR, Piot P, Cameron DW. "Standardization of an enzyme immunoassay for human antibody to Haemophilus ducreyi.". 1992. Abstractstandardization_of_an_enzyme_immunoassay_for_human_antibody_to_haemophilus_ducreyi.pdf

We standardized a serologic enzyme immunoassay (EIA) for human immunoglobulin G and M antibodies against Haemophilus ducreyi. We evaluated the performance of this test with respect to the time from acute chancroid and coinfection with human immunodeficiency virus (HIV). Antibody to a crude, soluble bacterial antigen of one H. ducreyi strain was detected in a panel of serum samples from clinically and microbiologically confirmed cases of chancroid and from controls. Test interpretation was standardized for optimal sensitivity and specificity. Performance of the EIA was enhanced in the period of early convalescence from acute primary chancroid and was not diminished in the presence of HIV coinfection. The EIA performed adequately as a serologic screening test for field evaluation and epidemiologic application in conjunction with sexually transmitted disease and HIV detection and control efforts.

Descamps P, Jourdain O, Paillet C, Toutain A, Guichet A, Pourcelot D, Gold F, Castiel M, Body G. "Etiology, prognosis and management of nuchal cystic hygroma: 25 new cases and literature review." European Journal of Obstetrics & Gynecology and Reproductive Biology. 1997;71:3-10. AbstractWebsite

Objective: To develop an algorithm for the prenatal management of patients when a cystic hygroma is diagnosed by ultrasonography. Methods: We report a personal series of 25 cases diagnosed between 10 and 23 weeks gestation and a review of the literature comprising a total of 999 cases. We focused on the etiologies and the value of various prognostic factors in the management of cystic hygromas. These include karyotype, alpha-fetoprotein levels, sonographic findings in the fetus and within the hygroma itself, and natural history. Results: According to the literature, fetal chromosomal abnormalities were associated with cystic hygromas in 62% of the cases. Turner's syndrome remains the most common (33%) but Down's syndrome, Trisomy 18 and Trisomy 13 are not rare (15, 7 and 2%). Others have Mendelian abnormalities. The prognosis remains gloomy. The literature reports that only 9% of cases result in healthy children with normal karyotypes. The remaining 91% are either terminated (89%) or liveborn (2%), but with chromosome abnormalities or various malformations. Conclusion: The prognostic factors associated with a poor outcome are an abnormal karyotype and associated structural malformations. Resolution of the hygroma by 20 weeks gestation suggests a good prognosis, but is not definitive. All other factors evaluated do not appear to be of prognostic value at this time. Careful analysis of these prognostic factors is very important to identify the small percentage of normal children and to advise parents effectively for a future pregnancy.

Derese S. "Antiplasmodial and antileishmanial flavonoids from Mundulea sericea." Fitoterapia . 2021;149:104796.
Derese S. "Evaluation of β-Sitosterol Loaded PLGA and PEG-PLA Nanoparticles for Effective Treatment of Breast Cancer: Preparation, Physicochemical Characterization, and Antitumor Activity." Pharmaceutics. 2018;10(4):232. Abstract

β-Sitosterol (β-Sit) is a dietary phytosterol with demonstrated anticancer activity against a panel of cancers, but its poor solubility in water limits its bioavailability and therapeutic efficacy. In this study, poly (lactide-co-glycolic acid)(PLGA) and block copolymers of poly (ethylene glycol)-block-poly (lactic acid)(PEG-PLA) were used to encapsulate β-Sit into nanoparticles with the aim of enhancing its in vitro anticancer activity. β-Sitosterol-loaded PLGA and PEG-PLA nanoparticles (β-Sit-PLGA and β-Sit-PEG-PLA) were prepared by using a simple emulsion-solvent evaporation technique. The nanoparticles were characterized for size, particle size distribution, surface charge, and encapsulation efficiency. Their cellular uptake and antiproliferative activity was evaluated against MCF-7 and MDA-MB-231 human breast cancer cells using flow cytometry and MTT assays, respectively. β-Sit-PLGA and β-Sit-PEG-PLA nanoparticles were spherical in shape with average particle sizes of 215.0±29.7 and 240.6±23.3 nm, a zeta potential of− 13.8±1.61 and− 23.5±0.27 mV, respectively, and with narrow size distribution. The encapsulation efficiency of β-Sit was 62.89±4.66 and 51.83±19.72% in PLGA and PEG-PLA nanoparticles, respectively. In vitro release in phosphate-buffered saline (PBS) and PBS/with 0.2% Tween 20 showed an initial burst release, followed by a sustained release for 408 h. β-Sit-PLGA nanoparticles were generally stable in a protein-rich medium, whereas β-Sit-PEG-PLA nanoparticles showed a tendency to aggregate. Flow cytometry analysis (FACS) indicated that β-Sit-PLGA nanoparticles were efficiently taken up by the cells in contrast to β …

Derese S. "4′-Prenyloxyderrone from the stem bark of Millettia oblata ssp. teitensis and the antiplasmodial activities of isoflavones from some Millettia species." Phytochemistry Letters. 2014;8:69-72. Abstract

4′-Prenyloxyderrone from the stem bark of Millettia oblata ssp. teitensis and the antiplasmodial activities of isoflavones from some Millettia species

Solomon Derese, Leonard Barasa, Hoseah M. Akala, Amir O. Yusuf, Edwin Kamau, Matthias Heydenreich, Abiy Yenesew

The CH2Cl2/MeOH (1:1) extract of the stem bark of Millettia oblata ssp. teitensis showed antiplasmodial activity (IC50 = 10–12 μg/mL) against the chloroquine-sensitive (D6) and chloroquine-resistant (W2) strains of Plasmodium falciparum. Chromatographic separation of the extract led to the isolation of a new isoflavone, 4′-prenyloxyderrone (1), together with known isoflavones (8-O-methylretusin, durmillone, maximaisoflavone B, maximaisoflavone H and maximaisoflavone J), a rotenoid (tephrosin) and a triterpene (lupeol). Similar investigation of Millettia leucantha resulted in the identification of the isoflavones afrormosin and wistin, and the flavone chrysin. The identification of these compounds was based on their spectroscopic data. Five of the isoflavones isolated from these plants as well as 11 previously reported compounds from Millettia dura were tested and showed good to moderate antiplasmodial activities (IC50 = 13–53 μM), with the new compound, 4′-prenyloxyderrone, being the most active (IC50 = 13–15 μM).

Derese S, Guantai EM, Yaouba S, Kuete V. "Mangifera indica L. (Anacardiaceae).". In: Medicinal Spices and Vegetables from Africa. London: Elsevier Academic Press; 2017.
Derese S. "Modeling and synthesis of antiplasmodial chromones, chromanones and chalcones based on natural products of Kenya." Biofarmasi Journal of Natural Product Biochemistry. 2018;16(1):8-21. Abstract

Scolastica M, Ndakala AJ, Derese S. 2018. Modeling and synthesis of antiplasmodial chromones, chromanones and chalcones based on natural products of Kenya. Biofarmasi J Nat Prod Biochem 16: 8-21. Despite numerous research that has been done on plants of Kenya resulting in the isolation of thousands of natural products, data on these natural products are not systematically organized in a readily accessible form. This has urged the construction of a web-based database of natural products of Kenya. The database is named Mitishamba and is hosted at http://mitishamba. uonbi. ac. ke. The Mitishamba database was queried for chromones, chromanones, and chalcones that were subjected to structure-based drug design using Fred (OpenEye) docking utility program with 1TV5 PDB structure of the PfDHODH receptor to identify complex of ligands that bind with the active site. Ligand-based drug design (Shape and electrostatics comparison) was also done on the ligands against query A77 1726 (38)(the ligand that co-crystallized with PfDHODH receptor) using ROCS and EON programs, respectively, of OpenEye suite. There was a substantial similarity among the top performing ligands in the docking studies with shape and electrostatic comparison that led to the identification of compounds of interest which were targeted for synthesis and antiplasmodial assay. In this study, a chromanone (7-hydroxy-2-(4-methoxyphenyl) chroman-4-one (48)) and two intermediate chalcones (2', 4'-dihydroxy-4-methoxychalcone (45) and 2’, 4’-dihydroxy-4-chlorochalcone (47)), were synthesized and subjected to antiplasmodial assay. Among these …

Derese S. "Seed, Foster, Believe, Dream and Act. Capacity Building in Kenya by Novartis Global Discovery Chemistry, Seeding Labs, the International Activities Committee, and the Computers in Chemistry Division of the ACS between 2010−2014.". In: ACS Symposium Series Vol 1195. Amercian Chemical Society; 2015. Abstract

Novartis initiated a Fellows program for African academic scientists in 2010 in partnership with Seeding Labs, providing a 9 week-long industrial immersion experience at the Novartis Institutes for Biomedical Research (NIBR) in Cambridge Massachusetts. Through their scientific projects and activities, the Fellows explored new laboratory techniques and improved their scientific communication and grant writing skills. A primary aim of the program was to influence the Fellows’ time in the NIBR laboratories into promoting research of potential utility to their scientific and teaching activities on returning home to their academic institutions, thus building strength in scientific capacity in Africa. As chemistry is an essential discipline in the drug-discovery process, it has been an area of focus for several visiting African Fellows and their NIBR scientific mentors. In particular, computational chemistry has minimal laboratory requirements and is ideally suited as an area for scientific capacity building in Africa. In addition, extending drug-discovery capabilities in African laboratories to assist natural products research is of interest, particularly concerning development of treatments for malaria, tuberculosis, HIV and, of recent concern, the West African Ebola outbreak. An ACS International Activities Committee Global Innovation Grant, granted in 2012 added financial momentum to this capacity building project, spurring our efforts in capturing a Canadian Grand Challenges award and the pursuit of funding from IUPAC. In 2014, this initiative reached two significant milestones, creation of its first job, a computational chemistry academic faculty position in Kenya, and the launch of an in-silico database of Kenyan natural products named Mitishamba.

Derese S. "Pterocarpans and isoflavones from the root bark of Millettia micans and of Millettia dura." Phytochemistry Letters . 2017;21:216-220. Abstract

From the CH2Cl2/CH3OH (1:1) extract of the root bark of Millettia micans, a new pterocarpan, (6aR,11aR)-3-hydroxy-7,8,9-trimethoxypterocarpan (1), named micanspterocarpan, was isolated. Similar investigation of the CH2Cl2/CH3OH (1:1) extract of the root bark of Millettia dura gave a further new pterocarpan, (6aR,11aR)-8,9-methylenedioxy-3-prenyloxypterocarpan (2), named 3-O-prenylmaackiain, along with six known isoflavones (3-8) and a chalcone (9). All purified compounds were identified by NMR and MS, whereas the absolute configurations of the new pterocarpans were established by chriptical data analyses including quantum chemical ECD calculation. Among the isolated constituents, calopogonium isoflavone B (3) and isoerythrin A-4′-(3-methylbut-2-enyl) ether (4) showed marginal activities against the 3D7 and the Dd2 strains of Plasmodium falciparum (70–90% inhibition at 40 μM). Maximaisoflavone B (5) and 7,2′-dimethoxy-4′,5′-methylenedioxyisoflavone (7) were weakly cytotoxic (IC50 153.5 and 174.1 μM, respectively) against the MDA-MB-231 human breast cancer cell line. None of the tested compounds showed in-vitro translation inhibitory activity or toxicity against the HEK-293 human embryonic kidney cell line at 40 μM.

Derese S, Yenesew A, Midiwo JO, Heydenreich, Peter MG. "The Chemotaxonomic Value Of Anthraquinones In Asphodelaceae.". 1994.Website
Derese S, Kerubo L, Yenesew A, Machumi F, Midiwo JO. "Natural Products from Plant Diversity and their Potential in Management of Neglected Diseases.". 2011. Abstractmidiwo_et_al._napreca_abstracct.pdfNatural Products from Plant Diversity and their Potential in Management of Neglected Diseases

Conventionally, neglected diseases are considered as a group of 13 infectious diseases that are . endemic in the low income populations in the tropical developing world. They can be classified as those caused by trypanosomal parasites, helminthes, bacteria and viruses. They cause death to an estimated 0.5- 1m people annually. Trypanosomal diseases are represented by Kala-azar or visceral leshmaniasis, African sleeping sickness (African trypanosomiasis) and Chaga's disease (American trypanosomiasis); the current drugs for these diseases are relatively toxic even though the disease is not that lethal. Helminth infections include schistosomiasis treated with the inexpensive praziquantel but which cannot stop re-infection; onchocerciasis (river blindness), on which anthelmintic treatment is being tried; dracunculiasis (guinea worm), which should have been eradicated in 2009; lymphatic filiriasis (elephantiasis), managed by anthelmintic treatments. The others are soil transmitted worms such as ascariasis (round worms), trichuriasis (whipworms) and hookworms which are really best controlled by good hygienic practices. Leprosy, trachoma, Buruli ulcer and cholera represent the prevalent bacterial problems. Viral infections are yellow and dengue fevers caused by flavivirus transmitted by Aedes aegyptii and Japanese encephilitis caused by a flavivirus transmitted by Culex tritaeniorhynchus; the viral infections can be controlled through vaccination (WHO, 2008).

Derese S. " A coumestan and a coumaronochromone from Millettia lasiantha ." Biochemical Systematics and Ecology. 2021;97:104277.
Derese S. "Antiplasmodial prenylated flavanonols from Tephrosia subtrifloran ." Natural product research. 2018;32(12):1407-1414. Abstract

The CH2Cl2/MeOH (1:1) extract of the aerial parts of Tephrosia subtriflora afforded a new flavanonol, named subtriflavanonol (1), along with the known flavanone spinoflavanone B, and the known flavanonols MS-II (2) and mundulinol. The structures were elucidated by the use of NMR spectroscopy and mass spectrometry. The absolute configuration of the flavanonols was determined based on quantum chemical ECD calculations. In the antiplasmodial assay, compound 2 showed the highest activity against chloroquine-sensitive Plasmodium falciparum reference clones (D6 and 3D7), artemisinin-sensitive isolate (F32-TEM) as well as field isolate (KSM 009) with IC50 values 1.4–4.6 μM without significant cytotoxicity against Vero and HEp2 cell lines (IC50 > 100 μM). The new compound (1) showed weak antiplasmodial activity, IC50 12.5–24.2 μM, but also showed selective anticancer activity against HEp2 cell line …

Derese S. Screening of Plant Extracts for Searching Antiplasmodial Activity. Madagascar: NAPRECA; 2005. Abstractscreening_of_plant_extracts_for_searching_antiplasmodial_activity.pdf

The aim objective of this study consists in isolating the active molecules from plants used in traditional medicine to treat malaria and its symptoms.
197 plants were collected following to the ethnobotanic investigations. Plants were dried, powdered and macerated in a hydroalcoholic solution. Resulting extracts have been assessed for in vitro & in vivo antimalarial and toxicity activities.
For the plants collected in Madagascar: 15 extracts (i.e. 16%) prepared from 91 medicinal plants (of which 57 are antimalarial) present an interesting antiplasmodial activity with a value of IC50 less than 10 μg/mL, their cytotoxicity are weak with a value of IC50 evaluated at more than 50 μg/mL. Two of these extracts have an ED50 lower than 100 mg/kg.
With regard to the Congolese plants: five out of twenty six (i.e. 19%) collected plants would be interesting.

Key words:
Malaria, Screening, Plants, Madagascar, Africa

Derese S. "Anti-inflammatory Flavanones and Flavones from Tephrosia linearis." Journal of natural products. 2020. AbstractWebsite

Anti-inflammatory Flavanones and Flavones from Tephrosia linearis
Richard Oriko Owor, Kibrom Gebreheiwot Bedane, Sebastian Zühlke, Solomon Derese, George Otieno Ong’amo, Albert Ndakala, Michael Spiteller
Abstract
Phytochemical analysis of a methanol–dichloromethane (1:1) extract of the aerial parts of Tephrosialinearis led to the isolation of 18 compounds. Seven of these, namely, lineaflavones A–D (1–4), 6-methoxygeraldone (5), 8″-acetylobovatin (6), and 5-hydroxy-7-methoxysaniculamin A (7) are new compounds. The compounds were characterized based on their NMR and HRMSn data. The anti-inflammatory effects of the crude extract and isolated compounds were evaluated by measuring the levels of interleukins (IL-1β, IL-2, and IL-6), granulocyte-macrophage colony-stimulating factor (GM-CSF), and tumor necrosis factor-α (TNF-α) in lipopolysaccharide (LPS)-stimulated peripheral blood mononuclear cells (PBMCs). The crude extract inhibited the release of all cytokines except IL-1β, which slightly increased in comparison to the LPS control. All the tested compounds suppressed the production of IL-2, GM-CSF, and TNF-α. Whereas compounds 1, 2, 4–8, 10–15, 17, and 18 decreased production of IL-6, compounds 1, 2, 4, 7, 10, 13–15, and 17 inhibited the release of IL-1β. It is worth noting that most of the compounds tested showed a superior reduction in cytokines release compared to the reference drug ibuprofen.

Derese S. "Antiplasmodial prenylated flavanonols from Tephrosia subtriflora." Natural Product Research. 2017;2017:1-8. AbstractWebsite

The CH2Cl2/MeOH (1:1) extract of the aerial parts of Tephrosia subtriflora afforded a new flavanonol, named subtriflavanonol (1), along with the known flavanone spinoflavanone B, and the known flavanonols MS-II (2) and mundulinol. The structures were elucidated by the use of NMR spectroscopy and mass spectrometry. The absolute configuration of the flavanonols was determined based on quantum chemical ECD calculations. In the antiplasmodial assay, compound 2 showed the highest activity against chloroquine-sensitive Plasmodium falciparum reference clones (D6 and 3D7), artemisinin-sensitive isolate (F32-TEM) as well as field isolate (KSM 009) with IC50 values 1.4–4.6 μM without significant cytotoxicity against Vero and HEp2 cell lines (IC50 > 100 μM). The new compound (1) showed weak antiplasmodial activity, IC50 12.5–24.2 μM, but also showed selective anticancer activity against HEp2 cell line (CC50 16.9 μM).

Derese S. "Two new flavonoids from Dracaena usambarensis Engl." Phytochemistry Letters. 2020;36:80-85. AbstractWebsite

Two new flavonoids from Dracaena usambarensis Engl.
Vaderament-A.Nchiozem-Ngnitedem, Leonidah Kerubo Omosa, Solomon Derese, PierreTane, Matthias Heydenreich, Michael Spiteller, Ean-Jeong Seo, Thomas Efferth

Investigations of the root extract of Dracaena usambarensis Engl. for anticancer principles led to the characterization of one new homoisoflavonoid, (3S)-3,4ʹ,5,6-tetrahydroxy-7-methoxyhomoisoflavanone (1) and a new retrodihydrochalcone, 4ʹ,4-dihydroxy-2,3-dimethoxydihydrochalcone (2) along with six previously reported compounds, including two homoisoflavonoids, 7-O-methyl-8-demethoxy-3-hydroxy-3,9-dihydropunctatin (3) and loureiriol (4); a phenolic amide, 3-(4ʹʹʹ-hydroxyphenyl)-N-[2ʹ-(4ʹʹ-hydroxyphenyl)-2ʹ-methoxyethyl]acrylamide (5); a spirostane, 25S-spirosta-1,4-dien-3-one (6) and two steroids, stigmasterol (7) and stigmasterol 3-O-β-D-glucopyranoside (8). The structures of 1-8 were determined using spectroscopic and spectrometric techniques. The absolute configurations of compounds 1 and 3 were achieved using circular dichroism spectroscopy. Using the resazurin reduction assay and doxorubicin as reference anticancer drug, 1 showed moderate cytotoxicity against drug sensitive CCRF-CEM but was inactive against all the other tested drug sensitive, resistance phenotypes and normal cells. The crude extract and 2-8 were inactive in the preliminary screening against CCRF-CEM and drug resistant CEM/ADR5000 cell lines. Interestingly, the activity of the standard drug, doxorubicin was comparable to those of inactive compounds against CEM/ADR5000 cells. Future studies should focus on structure modifications of 1-3, in order to obtain more potent analogues.

Derese S. "Cytotoxicity of isoflavones from Millettia dura." Natural Product Research. 2021;35(16):2744-2747.
Derese S. "Antiplasmodial activity of compounds from the surface exudates of Senecio roseiflorus." Natural product communications. 2013;8(2):175-6. Abstract

Antiplasmodial activity of compounds from the surface exudates of Senecio roseiflorus.

Leonidah Omosa Kerubo, Jacob Ogweno Midiwo, Solomon Derese, Moses K Langat, Hosea M Akala, Norman C Waters, Martin Peter, Matthias
Natural Products Communications: 2013; 8(2):175-6.

From the surface exudates of Senecio roseiflorus fourteen known methylated flavonoids and one phenol were isolated and characterized. The structures of these compounds were determined on the basis of their spectroscopic analysis. The surface exudate and the flavonoids isolated showed moderate to good antiplasmodial activity with 5,4'-dihydroxy-7-dimethoxyflavanone having the highest activity against chloroquine-sensitive (D6) and resistant (W2) strains of Plasmodium falciparum, with IC50 values of 3.2 +/- 0.8 and 4.4 +/- 0.01 microg/mL respectively.

Derese S. "Flavonoids and Isoflavonoids of Millettia dura and Millettia ferruginea: Phytochemical review and chemotaxonomic values." Biochemical Systematics and Ecology. 2020;91. Abstract

The phytochemical information on Millettia dura Dunn, M. ferruginea (Hochst.) Baker and M. ferruginea subsp. darassana (Cufod.) J.B. Gillett was reviewed. All the three taxa elaborate mainly isoflavones (33 reported), occurring in the flowers, seeds/seed pods, stem bark and root bark. Out of the 33 isoflavones reported, some 19 (ca. 58%) contain prenyl at C-8 or its modification as 2,2-dimethylchromene ring at C-7/C-8, occurring in all the three taxa. Except for three isoflavones isolated from M. ferruginea subsp. darassana, all the isoflavones of these taxa are 5-deoxygenated. In these taxa, oxygenation at C-6 is a common feature, while isoflavones with C-8 oxygenation are rare, only three reported, and all of these from M. dura. There are 7 rotenoids reported from these taxa, and occur almost entirely in the seeds/seedpods of these plants. The major rotenoid with methylenedioxy group at C-2/C-3, millettone and its 12a-hydroxy derivative, millettosine, occur only in M. dura, this appears to distinguish M. dura from M. ferruginea.

Derese S. "Alkenyl cyclohexanone derivatives from Lannea rivae and Lannea schweinfurthii." Phytochemistry Letters. 2018;23:141-148. Abstractalkenyl_cyclohexanone_derivatives_from_lannea_rivae_and_lannea.pdfWebsite

Phytochemical investigation of the CH2Cl2/MeOH (1:1) extract of the roots of Lannea rivae (Chiov) Sacleux (Anacardiaceae) led to the isolation of a new alkenyl cyclohexenone derivative: (4R,6S)-4,6-dihydroxy-6-((Z)-nonadec-14′-en-1-yl)cyclohex-2-en-1-one (1), and a new alkenyl cyclohexanol derivative: (2S*,4R*,5S*)-2,4,5-trihydroxy-2-((Z)-nonadec-14′-en-1-yl)cyclohexanone (2) along with four known compounds, namely epicatechin gallate, taraxerol, taraxerone and β-sitosterol; while the stem bark afforded two known compounds, daucosterol and lupeol. Similar investigation of the roots of Lannea schweinfurthii (Engl.) Engl. led to the isolation of four known compounds: 3-((E)-nonadec-16′-enyl)phenol, 1-((E)-heptadec-14′-enyl)cyclohex-4-ene-1,3-diol, catechin, and 1-((E)-pentadec-12′-enyl)cyclohex-4-ene-1,3-diol. The structures of the isolated compounds were determined by NMR spectroscopy and mass spectrometry. The absolute configuration of compound 1 was established by quantum chemical ECD calculations. In an antibacterial activity assay using the microbroth kinetic method, compound 1 showed moderate activity against Escherichia coli while compound 2 exhibited moderate activity against Staphylococcus aureus. Compound 1 also showed moderate activity against E. coli using the disc diffusion method. The roots extract of L. rivae was notably cytotoxic against both the DU-145 prostate cancer cell line and the Vero mammalian cell line (CC50 = 5.24 and 5.20 μg/mL, respectively). Compound 1 was also strongly cytotoxic against the DU-145 cell line (CC50 = 0.55 μg/mL) but showed no observable cytotoxicity (CC50 > 100 μg/mL) against the Vero cell line. The roots extract of L. rivae and L. schweinfurthii, epicatechin gallate as well as compound 1 exhibited inhibition of carageenan-induced inflammation.

Derese S. "Crystal Structures and Cytotoxicity of ent-Kaurane-Type Diterpenoids from Two Aspilia Species." Molecules 23. 2018;23(12):3199. Abstract

A phytochemical investigation of the roots of Aspilia pluriseta led to the isolation of ent-kaurane-type diterpenoids and additional phytochemicals (1–23). The structures of the isolated compounds were elucidated based on Nuclear Magnetic Resonance (NMR) spectroscopic and mass spectrometric analyses. The absolute configurations of seven of the ent-kaurane-type diterpenoids (3–6, 6b, 7 and 8) were determined by single crystal X-ray diffraction studies. Eleven of the compounds were also isolated from the roots and the aerial parts of Aspilia mossambicensis. The literature NMR assignments for compounds 1 and 5 were revised. In a cytotoxicity assay, 12α-methoxy-ent-kaur-9 (11), 16-dien-19-oic acid (1)(IC 50= 27.3±1.9 µM) and 9β-hydroxy-15α-angeloyloxy-ent-kaur-16-en-19-oic acid (3)(IC 50= 24.7±2.8 µM) were the most cytotoxic against the hepatocellular carcinoma (Hep-G2) cell line, while 15α-angeloyloxy-16β, 17-epoxy-ent-kauran-19-oic acid (5)(IC 50= 30.7±1.7 µM) was the most cytotoxic against adenocarcinomic human alveolar basal epithelial (A549) cells.

Derese S, Yenesew A, Midiwo JO, Heydenreich, Peter MG. "Anthraquinones, Pre-anthraquinones And Isoeleutherol In The Roots Of Aloe Species."; 1994.
Derese S. "Silver–zinc oxide nanocomposite antiseptic from the extract of Bidens pilosa." Springer Nature Switzerland AG 2019. 2019;1(7):681. Abstractsilver-zinc_oxide_nanocomposite_antiseptic_from_the_extract_of_bidens.pdf

Silver nanoparticles (Ag-NPs), zinc oxide (ZnO-NPs) and zinc oxide–silver (ZnO–Ag-NPs) were biosynthesized based on
the rich matrix of alkaloids, flavones, tannins capping/stabilizing agents present in Bidens pilosa extract. Different plant
parts-root, leaf and seed ware used to prepare the plant extract for synthesis. Also, zinc and silver nitrate salts were
used as precursor materials. The surface plasmon peaks (SPR) based on the UV–Vis results for the Ag-NPs, ZnO-NPs were
located between 408–411 and 365–450 nm respectively. The SPR peaks for the Ag–ZnO-NPs occurred at 300–450 nm
indicating both blue and red shifts. The Ag–ZnO-NPs SPR shifts were associated with possible nanoparticle size reduction
and change in dielectric constant of the synthesis medium. Raman measurement peaks at 356, 484, 1350, 1578,
2435 cm−1 associated with OH, –C==C–, –C–O, S=O, =C–H moieties indicated successful capping. Nanoparticle yield was
temperature dependent and optimal yield could not be tied to a particular plant part as source of extract. Tunneling
electron microscope results showed Ag-NPs and ZnO-NPs were globular/spherical with a diameter range of 2–20 nm.
Interestingly, ZnO-NPs TEM displayed isolated miniaturized globular nanoparticles (< 2 nm) which then joined up to form
a large donut shaped structure indicating different formation mechanisms for the nanoparticles. XRD results showed the
Ag-NPs, ZnO-NPs and the Ag–ZnO-NPs particles were crystalline in nature. The high signal/noise in XRD originated from
possible crystalline biomaterials in the extracts. Energy dispersive spectroscopy (EDS) elemental composition results
confirmed successful formation of the nanoparticles. Anti-Microbial activity of the synthesized Ag-NPs, ZnO-NPs and
ZnO–Ag-NPs were studied against gram negative bacteria Escherichia coli (E. coli), gram positive bacteria Staphylococcus
aureus and fungus Candida albicans. Different ZnO: Ag-NPs nanocomposite ratios were used to test for antimicrobial
activity. Optimal antimicrobial activity was attained at Ag-NPs:ZnO-NPs ratio of 4:1 which also displayed the least minimum
inhibition concentration (MIC) and therefore was used as the active ingredient in formulating a hand sanitizing
antiseptic. The formulated antiseptic exhibited good antimicrobial activity.
Keywords

Derese S. "Synergistic anti-inflammatory activities of a new flavone and other flavonoids from Tephrosia hildebrandtii vatke." Natural Products Research. 2020. AbstractWebsite

Synergistic anti-inflammatory activities of a new flavone and other flavonoids from Tephrosia hildebrandtii vatke
Owor, R. O., Bedane, K. G., Openda, Y. I., Zühlke, S., Derese, S., Ong’amo, G., Ndakala, A., & Spiteller, M.
Abstract
A new flavone, named hildeflavone (1) along with 7 other known flavonoids were isolated from the aerial parts of Tephrosia hildebrandtii Vatke. Their characterisation was based on NMR and MS data analysis. The anti-inflammatory properties of the crude extract, isolated compounds and combination of the compounds were investigated in lipopolysaccharide (LPS)-stimulated peripheral blood mononuclear cells (PBMCs). Treatment of the LPS-stimulated PBMCs with the isolated flavonoids at a concentration of 100 µM significantly reduced the production of interleukins (IL-1β, IL-2 and IL-6), interferon-gamma (IFN-γ), granulocyte macrophage-colony stimulating factor (GM-CSF) and tumour necrosis factor-alpha (TNF-α). It was also found that the combination of a flavone and flavanones exhibited remarkable synergistic anti-inflammatory effects on the production of the cytokines.

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