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From various Ethiopian government food security strategies, the Productive Safety Net Program (PSNP) is one of the strategies to improve households’ consumption. As a result, the government needs to know the outcome of the program intervention for further decisions in similar poverty reduction strategies. This study examined the impact of Productive Safety Net Program intervention on food security of rural households in rural western Ethiopia. A cross-sectional survey data were gathered from a total of randomly selected 188 beneficiary and non-beneficiary sample households. Key informants interviews and focus group discussions were employed to triangulate household survey results. A Chi-square test was employed to compare the households’ food security status. The propensity score matching method was used to evaluate the impact of a Productive safety net on beneficiary households’ food security status. In this study, the Productive Safety net program has significantly increased households’ calorie intake. The beneficiaries’ households were more food secure than non-beneficiary households by 68% and54% respectively. The mean energy available for the beneficiary and non-beneficiary households is 2488.500 and 2153.394 kcal, respectively. Estimates of the average treatment effect of the treated indicated that a Productive safety net program can impact households food security by 2519.29348 kilocalories, higher in the kernel matching method. This is an encouraging indicator for Programme implementers and funding agents. Therefore, channeling further efforts on this indicator is important for a more pronounced impact of the Programme. Given a certain level of variations of different program impact studies, this study recommends further research with greater scope and at different locations on the impact of PSNP and related Food Security Programs on households’ food security status.

BackgroundThis study aims to understand the key factors influencing guardians’ decisions when purchasing spectacles for their children in semi-urban and urban areas of Cross River State, Nigeria, where a spectacle cross-subsidisation scheme will be implemented.MethodsThis cross-sectional study was conducted among all consecutive guardians visiting the Calabar (urban), Ugep, Ikom and Ogoja (semi-urban) public eye clinics in Cross River State, southern Nigeria, from August 1 to October 31 2019, and whose children had significant refractive errors (myopia ≤-0.50D, hyperopia ≥1.50D, astigmatism >0.75D) and received spectacles. Guardians were interviewed using a questionnaire which included i) close-ended questions on reasons guardians choose to purchase spectacles for their children in eye clinics, ii) guardians’ perceptions of the quality and design of children’s current spectacle, iii) factors most heavily influencing their choice of spectacles for children, and iv) open-ended questions to seek guardians’ suggestions on how to improve the current spectacle range.ResultsAll 137 eligible guardians (67.2% women [n = 92]) who visited the selected eye clinics participated in the study (response rate = 100%), with 109 (79.6%) from semi-urban and 28 (20.4%) attending urban clinics. Guardians from both urban and semi-urban clinics prioritised frame design, quality, and material as the main factors affecting their decision when purchasing spectacles for their children. Female guardians and those with higher incomes were both 1.5 times more likely to emphasise frame quality when describing selection criteria for purchasing spectacles for their children than male guardians (p = 0.01) or guardians earning less (p = 0.03).ConclusionDesign, material, and frame quality are key factors influencing guardians when purchasing spectacles for their children in these setting and female guardians or those with higher income prioritise frame quality. This study could guide the planning and implementation of a novel cross-subsidisation scheme in Cross River State.

Background The coverage of long lasting insecticidal nets (LLIN) and intermittent preventive treatment of malaria in pregnancy (IPTp) uptake for the prevention of malaria commonly vary by geography. Many sub-Saharan Africa (SSA) countries, including Nigeria are adopting the use of LLIN and IPTp to fight malaria. Albeit, the coverage of these interventions to prevent malaria across geographical divisions have been understudied in many countries. In this study, we aimed to explore the differentials in LLIN and IPTp uptake across Nigerian geopolitical zones. Methods We analyzed data from Nigeria Multiple Indicator Cluster Survey (MICS) 2016–17. The outcome variables were IPTp and LLIN uptake among women of childbearing age (15–49 years). A total sample of 24,344 women who had given birth were examined for IPTp use and 36,176 women for LLIN use. Percentages, Chi-square test and multivariable logit models plots were used to examine the geopolitical zones differentials in IPTp and LLIN utilization. Data was analyzed at 5% level of significance. Results The overall prevalence of IPTp was 76.0% in Nigeria. Moreover, there were differences across geopolitical zones: North Central (71.3%), North East (76.9%), North West (78.2%), South East (76.1%), South South (79.7%) and South West (72.4%) respectively. Furthermore, the prevalence of LLIN was 87.7%% in Nigeria. Also, there were differences across geopolitical zones: North Central (89.1%), North East (91.8%), North West (90.0%), South East (77.3%), South South (81.1%) and South West (69.8%) respectively. Women who have access to media use, married, educated and non-poor were more likely to uptake IPTp. On the other hand, rural dwellers and those with media use were more likely to use LLIN. Conversely, married, educated, non-poor and women aged 25–34 and 35+ were less likely to use LLIN. Conclusion Though the utilization of IPTp and LLIN was relatively high, full coverage are yet to be achieved. There was geopolitical zones differentials in the prevalence of IPTp and LLIN in Nigeria. Promoting the utilization of IPTp and LLINs across the six geopolitical zones through intensive health education and widespread mass media campaigns will help to achieve the full scale IPTp and LLIN utilization.

Background A global epidemic of obesity has been documented, particularly among African countries. While central obesity and overweight have been reported for many countries, very limited information exists about the prevalence of these health problems in Sudan, and these data are nonexistent for Eastern Sudan. The present study aimed to determine the prevalence of obesity and central obesity, as well as the factors associated with both, among adults in Gadarif, Eastern Sudan. Methods A cross-sectional study was conducted in Gadarif, Eastern Sudan, during the period of January through May 2018. Sociodemographic and health characteristics data were collected through a questionnaire. Body mass index (BMI) and waist circumference (WC) were measured using the standard methods. Both descriptive and inferential statics were applied to analyze the data. Results A total of 594 adults participated in the study; 70.4% of them were female. The mean (standard deviation) age was 44.98 (16.64) years. Of the 594 enrolled participants, 33.7%, 7.4%, 26.8%, and 32.2% were normal weight, underweight, overweight, and obese, respectively. The prevalence of central obesity was (67.8%). Approximately, one-third of the participants (29.29%) were obese and had central obesity. In the multinomial regression, being married was the main risk factor associated with overweight, and older age, female sex, being married and hypertension were significantly associated with obesity. In the binary regression, the main risk factors associated with central obesity were female sex and being married. Conclusion The prevalence rates of both obesity and central obesity among the study participants were high. Older age and hypertension were only associated with obesity. Obesity and central obesity were significantly associated with female sex and being married. This study provided valuable baseline information to develop appropriate strategies for the prevention and control of obesity in Eastern Sudan.

SettingFemale genital mutilation (FGM) is a traditional surgical modification of the female genitalia comprising all procedures involving partial or total removal of the external female genitalia or other injury to the female genital organs for cultural or nontherapeutic reasons. It can be harmful and violates girls' and women's human rights. FGM is a worldwide problem but mainly practiced in Africa. FGM is still widely practiced in Ethiopia despite being made a criminal offence in 2004.ObjectiveUsing data from three Ethiopian Demographic Health Surveys (EDHS) conducted in 2000, 2005 and 2016 the objective was to assess changes in prevalence of FGM and associated factors among women of reproductive age and their daughters.MethodsEDHS datasets for the three surveys included data on FGM prevalence and socio-demographic factors. After weighting, the data were analysed using frequencies, proportions and the chi square test for trend. Categorical variables associated with FGM in 2016 were compared using OpenEpi and presented as prevalence ratios (Pr) with 95% Confidence Intervals (CI). Levels of significance were set at 5% (PResultsThere was overall decline in FGM prevalence (from 79.9% to 74.3% to 65.2%, P95%, lack of school education, coming from rural areas and living in less wealthy households.ConclusionAlthough progress has been slow, the prevalence of FGM in Ethiopia has declined over time. Recommendations to quicken the trajectory of decline targeting integrated interventions to high prevalence areas focusing on mothers, fathers, youngsters, religious leaders and schools and ensuring that all girls receive some form of education.

Setting Since August 2016, after the Ebola outbreak, the Guinean National Tuberculosis Programme and Damien Foundation implemented the shorter treatment regimen (STR) for multidrug-resistant tuberculosis (MDR-TB) in the three MDR-TB sites of Conakry. Previously, the longer regimen was used to treat MDR-TB. Objectives In a post-Ebola context, with a weakened health system, we describe the MDR-TB treatment uptake, patients characteristics, treatment outcomes and estimate the effect of using the longer versus STR on having a programmatically adverse outcome. Design This is a retrospective cohort study in RR-TB patients treated with either the longer regimen or STR. Results In Conakry, in 2016 and 2017, 131 and 219 patients were diagnosed with rifampicin-resistant tuberculosis (RR-TB); and 108 and 163 started treatment, respectively. Of 271 patients who started treatment, 75 were treated with the longer regimen and 196 with the STR. Patients characteristics were similar regardless of the regimen except that the median age was higher among those treated with a longer regimen (30 years (IQR:24–38) versus 26 years (IQR:21–39) for the STR. Patients treated with a STR were more likely to obtain a programmatically favorable outcome (74.0% vs 58.7%, p = 0.01) as lost to follow up was higher among those treated with a longer regimen (20.0% vs 8.2%, p = 0.006). Patients on a longer regimen were more than 2 times more likely (aOR: 2.5; 95%CI:1.3,4.7) to have a programmatically adverse outcome as well as being 45 years or older (aOR: 2.8; 95%CI:1.3,6.2), HIV positive (aOR:3.3; 95%CI:1.6,6.6) and attendance at a clinic without NGO support (aOR:3.0; 95%:1.6,5.7). Conclusion In Guinea, patients treated with the STR were more likely to have a successful outcome than those treated with the longer MDR-TB treatment regimen. Lost to follow-up was higher in patients on the longer regimen. However, STR treatment outcomes were less good than those reported in the region.

While it is generally accepted that language and speech have genetic foundations, and that the widespread inter-individual variation observed in many of their aspects is partly driven by variation in genes, it is much less clear if differences between languages may also be partly rooted in our genes. One such proposal is that the population frequencies of the so-called “derived” alleles of two genes involved in brain growth and development,ASPMandMicrocephalin, are related to the probability of speaking a tone language or not. The original study introducing this proposal used a cross-linguistic statistical approach, showing that these associations are “special” when compared with many other possible relationships between genetic variants and linguistic features. Recent experimental evidence supports strongly a negative effect of the “derived” allele ofASPMon tone perception and/or processing within individuals, but failed to find any effect forMicrocephalin. Motivated by these experimental findings, I conduct here a cross-linguistic statistical test, using a larger and updated dataset of 175 samples from 129 unique (meta)populations, and a battery of methods including mixed-effects regression (Bayesian and maximum-likelihood), mediation and path analysis, decision trees and random forests, using permutations and restricted sampling to control for the confounding effects of genealogy (language families) and contact (macroareas). Overall, the results support a negative weak effect ofASPM-D against the presence of tone above and beyond the strong confounding influences of genealogy and contact, but they suggest that the original association between tone andMCPH1might have been a false positive, explained by differences between populations and languages within and outside Africa. Thus, these cross-linguistic population-scale statistical results are fully consonant with the inter-individual-level experimental results, and suggest that the observed linguistic diversity may be, at least in some cases, partly driven by genetic diversity.

Background Leprosy elimination defined as a registered prevalence rate of less than 1 case per 10,000 persons was achieved in Kenya at the national level in 1989. However, there are still pockets of leprosy in some counties where late diagnosis and consequent physical disability persist. The epidemiology of leprosy in Kenya for the period 2012 through to 2015 was defined using spatial methods. Methods This was a retrospective ecological correlational study that utilized leprosy case based data extracted from the National Leprosy Control Program database. Geographic information system and demographic data were obtained from Kenya National Bureau of Statistics (KNBS). Chi square tests were carried out to check for association between sociodemographic factors and disease indicators. Two Spatial Poisson Conditional Autoregressive (CAR) models were fitted in WinBUGS 1.4 software. The first model included all leprosy cases (new, retreatment, transfers from another health facility) and the second one included only new leprosy cases. These models were used to estimate leprosy relative risks per county as compared to the whole country i.e. the risk of presenting with leprosy given the geographical location. Principal findings Children aged less than 15 years accounted for 7.5% of all leprosy cases indicating active leprosy transmission in Kenya. The risk of leprosy notification increased by about 5% for every 1 year increase in age, whereas a 1% increase in the proportion of MB cases increased the chances of new leprosy case notification by 4%. When compared to the whole country, counties with the highest risk of leprosy include Kwale (relative risk of 15), Kilifi (RR;8.9) and Homabay (RR;4.1), whereas Turkana had the lowest relative risk of 0.005. Conclusion Leprosy incidence exhibits geographical variation and there is need to institute tailored local control measures in these areas to reduce the burden of disability., Author summary Leprosy is a chronic bacterial disease that mainly affects the nerves. If untreated, it may cause progressive and permanent damage to the skin, nerves, limbs, and eyes leading to physical disability. Through use of a combination of drugs, Kenya was able to declare the disease as eliminated in the year 1989. However, there are still pockets of leprosy in some Kenyan counties where physical disability persists, mainly due to late diagnosis. To be able to curb this disease, control measures must be intensified, especially in the counties reporting more cases. We used data of the leprosy cases reported in Kenya for the period 2012 through to 2015 in order to describe geographical variation and factors influencing this variation. More than half of the registered cases had visible physical disability. The risk of leprosy notification increased with an increase in age as well as the severity of disease. We estimated that people living in Kwale, Kilifi and Homabay counties are 15, 9, and 5 times respectively more at risk of leprosy as compared to the whole country. Given the limited resources, it’s therefore paramount that high risk counties be initially targeted for control, with a focus on early diagnosis.

Treatment failure is a key challenge in the management of HIV-1 infection. We conducted a mixed-model survey of plasma nevirapine (NVP) concentrations (cNVP) and viral load in order to examine associations with treatment and adherence outcomes among Kenyan patients on prolonged antiretroviral therapy (ART). Blood plasma was collected at 1, 4 and 24 hours post-ART dosing from 58 subjects receiving NVP-containing ART and used to determine cNVP and viral load (VL). Median duration of treatment was 42 (range, 12–156) months, and 25 (43.1%) of the patients had virologic failure (VF). cNVP was significantly lower for VF than non- VF at 1hr (mean, 2,111ng/ml vs. 3,432ng/ml, p = 0.003) and at 4hr (mean 1,625ng/ml vs. 3,999ng/ml, p = 0.001) but not at 24hr post-ART dosing. Up to 53.4%, 24.1% and 22.4% of the subjects had good, fair and poor adherence respectively. cNVP levels peaked and were > = 3μg.ml at 4 hours in a majority of patients with good adherence and those without VF. Using a threshold of 3μg/ml for optimal therapeutic nevirapine level, 74% (43/58), 65.5% (38/58) and 86% (50/58) of all patients had sub-therapeutic cNVP at 1, 4 and 24 hours respectively. cNVP at 4 hours was associated with adherence (p = 0.05) and virologic VF (p = 0.002) in a chi-square test. These mean cNVP levels differed significantly in non-parametric tests between adherence categories at 1hr (p = 0.005) and 4hrs (p = 0.01) and between ART regimen categories at 1hr (p = 0.004) and 4hrs (p

Background In 2013, Uganda updated its prevention of maternal-to-child transmission of HIV program to Option B+, which requires that all HIV-infected pregnant and breastfeeding women be started on lifelong antiretroviral therapy (ART) regardless of CD4 count. We describe retention in care and factors associated with loss to follow-up (LTFU) among women initiated on Option B+ as part of an evaluation of the effectiveness of the national program. Methods We conducted a retrospective cohort analysis of data abstracted from records of 2,169 women enrolled on Option B+ between January and March 2013 from a representative sample of 145 health facilities in all 24 districts of the Central region of Uganda. We defined retention as “being alive and receiving ART at the last clinic visit”. We used Kaplan-Meier analysis to estimate retention in care and compared differences between women retained in care and those LTFU using the chi-squared test for dichotomized or categorical variables. Results The median follow-up time was 20.2 months (IQR 4.2–22.5). The proportion of women retained in HIV care at 6, 12 and 18 months post-ART initiation was 74.2%, 66.7% and 62.0%, respectively. Retention at 18 months varied significantly by level of health facility and ranged from 70.0% among those seen at hospitals to 56.6% among those seen at lower level health facilities. LTFU was higher among women aged less than 25 years, 59.3% compared to those aged 25 years and above, 40.7% (p = 0.02); among those attending care at lower level facilities, 44.0% compared to those attending care at hospitals, 34.1% (p = 0.01), and among those who were not tested for CD4 cell count at ART initiation, 69.4% compared to those who were tested, 30.9% (p = 0.002). Conclusion Retention of women who were initiated on Option B+ during the early phases of roll-out was only moderate, and could undermine the effectiveness of the program. Identifying reasons why women drop out and designing targeted interventions for improved retention should be a priority.

Background Self-reported male circumcision (MC) status is widely used to estimate community prevalence of circumcision, although its accuracy varies in different settings depending on the extent of misreporting. Despite this challenge, self-reported MC status remains essential because it is the most feasible method of collecting MC status data in community surveys. Therefore, its accuracy is an important determinant of the reliability of MC prevalence estimates based on such surveys. We measured the concurrence between self-reported and physically verified MC status among men aged 25–39 years during a baseline household survey for a study to test strategies for enhancing MC uptake by older men in Nyanza region of Kenya. The objective was to determine the accuracy of self-reported MC status in communities where MC for HIV prevention is being rolled out. Methods Agreement between self-reported and physically verified MC status was measured among 4,232 men. A structured questionnaire was used to collect data on MC status followed by physical examination to verify the actual MC status whose outcome was recorded as fully circumcised (no foreskin), partially circumcised (foreskin is past corona sulcus but covers less than half of the glans) or uncircumcised (foreskin covers half or more of the glans). The sensitivity and specificity of self-reported MC status were calculated using physically verified MC status as the gold standard. Results Out of 4,232 men, 2,197 (51.9%) reported being circumcised, of whom 99.0% were confirmed to be fully circumcised on physical examination. Among 2,035 men who reported being uncircumcised, 93.7% (1,907/2,035) were confirmed uncircumcised on physical examination. Agreement between self-reported and physically verified MC status was almost perfect, kappa (k) = 98.6% (95% CI, 98.1%-99.1%. The sensitivity of self-reporting being circumcised was 99.6% (95% CI, 99.2–99.8) while specificity of self-reporting uncircumcised was 99.0% (95% CI, 98.4–99.4) and did not differ significantly by age group based on chi-square test. Rate of consenting to physical verification of MC status differed by client characteristics; unemployed men were more likely to consent to physical verification (odds ratio [OR] = 1.48, (95% CI, 1.30–1.69) compared to employed men and those with post-secondary education were less likely to consent to physical verification than those with primary education or less (odds ratio [OR] = 0.61, (95% CI, 0.51–0.74). Conclusions In this Kenyan context, both sensitivity and specificity of self-reported MC status was high; therefore, MC prevalence estimates based on self-reported MC status should be deemed accurate and applicable for planning. However MC programs should assess accuracy of self-reported MC status periodically for any secular changes that may undermine its usefulness for estimating community MC prevalence in their unique settings.

Background South Africa has undergone multiple expansions in antiretroviral therapy (ART) eligibility from an initial CD4+ threshold of ≤200 cells/μl to providing ART for all people living with HIV (PLWH) as of September 2016. We evaluated the association of programmatic changes in ART eligibility with loss from care, both prior to ART initiation and within the first 16 weeks of starting treatment, during a period of programmatic expansion to ART treatment at CD4+ ≤ 350 cells/μl. Methods and findings We performed a retrospective cohort study of 4,025 treatment-eligible, non-pregnant PLWH accessing care in a community health center in Gugulethu Township affiliated with the Desmond Tutu HIV Centre in Cape Town. The median age of participants was 34 years (IQR 28–41 years), almost 62% were female, and the median CD4+ count was 173 cells/μl (IQR 92–254 cells/μl). Participants were stratified into 2 cohorts: an early cohort, enrolled into care at the health center from 1 January 2009 to 31 August 2011, when guidelines mandated that ART initiation required CD4+ ≤ 200 cells/μl, pregnancy, advanced clinical symptoms (World Health Organization [WHO] stage 4), or comorbidity (active tuberculosis); and a later cohort, enrolled into care from 1 September 2011 to 31 December 2013, when the treatment threshold had been expanded to CD4+ ≤ 350 cells/μl. Demographic and clinical factors were compared before and after the policy change using chi-squared tests to identify potentially confounding covariates, and logistic regression models were used to estimate the risk of pre-treatment (pre-ART) loss from care and early loss within the first 16 weeks on treatment, adjusting for age, baseline CD4+, and WHO stage. Compared with participants in the later cohort, participants in the earlier cohort had significantly more advanced disease: median CD4+ 146 cells/μl versus 214 cells/μl (p < 0.001), 61.1% WHO stage 3/4 disease versus 42.8% (p < 0.001), and pre-ART mortality of 34.2% versus 16.7% (p < 0.001). In total, 385 ART-eligible PLWH (9.6%) failed to initiate ART, of whom 25.7% died before ever starting treatment. Of the 3,640 people who started treatment, 58 (1.6%) died within the first 16 weeks in care, and an additional 644 (17.7%) were lost from care within 16 weeks of starting ART. PLWH who did start treatment in the later cohort were significantly more likely to discontinue care in, In a retrospective cohort study, Ingrid Katz and colleagues report on the continuity of care for people with HIV in Gugulethu Township, South Africa, Author summary Why was this study done? Global HIV treatment initiatives have focused on increasing access to antiretroviral therapy, with the goal of creating an “AIDS-free generation.” In line with guidelines put forth by the World Health Organization, the focus is on starting newly diagnosed people on immediate treatment and maintaining long-term retention in care. There is growing evidence, however, that treatment availability alone is insufficient to stop the spread of the disease. In countries where HIV is hyperendemic such as South Africa, it remains unclear if expanding treatment eligibility to all individuals living with HIV will have an impact on patients’ engagement in care and early retention on treatment. We performed this study in a large, urban community HIV treatment site in Cape Town to understand the association of South Africa’s expanding treatment program with pre-treatment loss from care and early loss from care during treatment. What did the researchers do and find? We performed a retrospective study of 2 cohorts (which included over 4,000 treatment-eligible people living with HIV in total) who entered care at a community health center in Cape Town: an early cohort, enrolled into care from January 2009 to August 2011, when guidelines mandated that ART initiation required a CD4+ cell count of ≤200 cells/μl, pregnancy, advanced clinical symptoms (World Health Organization stage 4), or comorbidity (active tuberculosis), and a later cohort, enrolled September 2011 to December 2013, when the treatment threshold had been expanded to CD4+ ≤ 350 cells/μl. We determined the risk of pre-treatment and early losses (

Aim: To develop a simple method that (1) combines the notions of biotic elements (groups of taxa with ranges significantly more similar to each other than to the ranges of other taxa) and of areas of endemism (AoE, areas of non-random distributional congruence among taxa), and (2) overcomes the constraints of a previously suggested null model-based method that cannot deal with disjunctions and is strictly grid-dependent. Location: We used test data sets from southern Africa and Crete. Methods: First, we used a null-model approach to detect pairs of species that have a significant degree of co-occurrence, in order to determine biotic elements. Subsequently, we used a parsimony analysis of endemicity to delineate candidate AoE, and multivariate analysis to define groups of biotic elements on the basis of species interactions (co-occurrence, mutual exclusion, neutral) using only the species detected in the previous step. We applied this method to the well known data set for Sciobius in southern Africa, as well as to endemic invertebrates of Crete (Greece), in order to evaluate its performance. Results: Our results are very similar to those of previous analyses, and produce meaningful delineation of AoE and biotic elements in both data sets. The method is flexible regarding null models and significance levels, and eliminates noise in the data. Main conclusions: We offer a simple method that provides reasonable identification of both biotic elements and AoE, produces good-fit statistics, reduces uninformative or junk output, and reduces computational time. © 2007 The Authors. 35 893 902 Cited By :18

The study investigated the causes and effects of marital conflict, as perceived by teachers, on the educational and social development of pupils in primary schools. A sample size of 400 respondents (255 males and 145 females) were drawn from the entire population in the seven local government areas of the district. The survey research design was adopted for the study. The instrument used for data collection was the questionnaire based on Teachers Perception on Marital conflict (TPMCO). The data collected were subjected to mean evaluation, while the chi-square (X2) was used to test hypothesis. The findings revealed that 55.0 % of teachers agreed that infidelity was the major cause of marital conflict with the highest mean value of 4.27, followed by poor communication between couple having 30.5 % of respondents, with a mean value of 3.92. The deprivation of instructional materials, followed by poor academic performance respectively, with the mean values of 4.82 and 3.94, were perceived by teachers, in order of ranking, as the most serious issues affecting the educational and social development of primary school pupils as a result of marital conflict. Love followed by encouragement were perceived by teachers to be the major ways in improving the educational and social development of pupils from conflict ridden homes. On hypothesis testing, marital conflict significantly (P≤0.05) affected the educational and social development of pupils, thus null hypothesis was rejected, while the alternate hypothesis was accepted.

This paper proposes a statistical test of the single-species hypothesis using non-metric characters as a complement to statistical tests using more traditional metric characters. The sample examined is that of Asian and African Homo erectus. The paleoanthropological community is divided on the taxonomic distinction of these fossils, with workers arguing both for and against the species-level distinction between Asian and African populations. Previous arguments have focused on patterns of apparent morphological differentiation between the African and Asian cranial samples. To assess this question, three tests were performed that compared the range of variation in the fossil sample to a single-species group with a similar geographic distribution; this comparative sample was composed of 221 modern humans from Africa and Asia. For the first test, 23 metric characters were analyzed on the fossil and comparative samples. Using resampling procedures, the variation for these characters was examined, recreating 1000 samples from the human analogs and comparing the CV distributions of these samples to the CVs of the fossil group. The second test used the metric data to calculate a Euclidean distance between the African and Asian fossil samples. This distance was compared to a distribution of Euclidean distances calculated between 1000 randomly selected samples of African and Asian modern humans. For the third test, a grading scale was created for ten non-metric characters that encompassed the total morphological variation found in the fossil and modern human samples. The Manhattan distance between the Asian and African fossil samples was calculated and compared to a distribution of distances calculated between 1000 randomly selected samples of African and Asian moderns. The first two tests, using the metric data, failed to falsify the null hypothesis. However, in the third test, using non-metric data, the total Manhattan distance for the fossil sample approached the 100th percentile of the resampled distances calculated from the moderns. The implications of the contrasting results are discussed.

The recurrent fixation of newly arising, beneficial mutations in a species reduces levels of linked neutral variability. Models positing frequent weakly beneficial substitutions or, alternatively, rare, strongly selected substitutions predict similar average effects on linked neutral variability, if the product of the rate and strength of selection is held constant. We propose an approximate Bayesian (ABC) polymorphism-based estimator that can be used to distinguish between these models, and apply it to multi-locus data from Drosophila melanogaster. We investigate the extent to which inference about the strength of selection is sensitive to assumptions about the underlying distributions of the rates of substitution and recombination, the strength of selection, heterogeneity in mutation rate, as well as the population's demographic history. We show that assuming fixed values of selection parameters in estimation leads to overestimates of the strength of selection and underestimates of the rate. We estimate parameters for an African population of D. melanogaster (ŝ∼2E−03, ) and compare these to previous estimates. Finally, we show that surveying larger genomic regions is expected to lend much more discriminatory power to the approach. It will thus be of great interest to apply this method to emerging whole-genome polymorphism data sets in many taxa., Author Summary Understanding the process of adaptive evolution requires quantifying the extent to which beneficial mutations contribute to differences between species. However, fundamental parameters of adaptation, such as the rate and strength of beneficial mutations, are poorly understood and have historically been difficult to estimate from data. In particular, distinguishing a high rate of weakly selected substitutions from a low rate of strongly selected substitutions has been problematic. Here, we introduce a new method to estimate the parameters of adaptive evolution from multi-locus population genetic data. We conduct simulations to show that this method is able to discriminate the rare/strong model from the frequent/weak model. Applying this method to an African population sample of Drosophila melanogaster, we estimate selection parameters and find that recurrent adaptive evolution has reduced genome variability by ∼50% on average. The availability of genome-scale population genetic data will lend considerable discriminatory power to the approach. Thus, this new approach represents an important step towards characterizing the nature of adaptive evolution in natural populations.

The problem of identifying motifs comprising nucleotides at a set of polymorphic DNA sites, not necessarily contiguous, arises in many human genetic problems. However, when the sites are not contiguous, no efficient algorithm exists for polymorphic motif identification. A search based on complete enumeration is computationally inefficient. We have developed probabilistic search algorithms to discover motifs of known or unknown lengths. We have developed statistical tests of significance for assessing a motif discovery, and a statistical criterion for simultaneously estimating motif length and discovering it. We have tested these algorithms on various synthetic data sets and have shown that they are very efficient, in the sense that the “true” motifs can be detected in the vast majority of replications and in a small number of iterations. Additionally, we have applied them to some real data sets and have shown that they are able to identify known motifs. In certain applications, it is pertinent to find motifs that contain contrasting nucleotides at the sites included in the motif (e.g., motifs identified in case-control association studies). For this, we have suggested appropriate modifications. Using simulations, we have discovered that the success rate of identification of the correct motif is high in case-control studies except when relative risks are small. Our analyses of evolutionary data sets resulted in the identification of some motifs that appear to have important implications on human evolutionary inference. These algorithms can easily be implemented to discover motifs from multilocus genotype data by simple numerical recoding of genotypes.