Detoxification enzymes activities in deltamethrin and bendiocarb resistant and susceptible malarial vectors (Anopheles gambiae) breeding in Bichi agricultural and residential sites, Kano state, Nigeria

Insecticide resistance is an important impediment to malaria control effort. Knowledge of insecticides resistance status is an essential tools to governmental, nongovernmental and insecticides producing industries whose daily challenge is minimization of malaria burden across the globe. Larvae of Anopheles gambiae collected from residential and agricultural areas of Bichi LGA, Kano States, North west Nigeria were reared to adults. Resistance and susceptibility status in the adults mosquitoes were studied by WHO paper bioassay impregnated with diagnostic dose of Deltamethrin and Bendiocarb. The insecticides resistance and susceptible adult mosquitoes of Bichi; residential areas (BR) and agricultural areas (BA) were respectively designated as BRr, BRs, BAr and BAs. Specific activities of insecticides detoxifying enzymes glutathione S transferase (GST), esterase and monooxygenase in resistant and susceptible vectors were measured using standard WHO methods. Although the levels of resistance varied with the insecticides and breeding site, high resistance status of malaria vectors to deltamethrin was recorded in both study sites (> 80% mortality) and incipient resistance (Tolerance) to bendiocarb (>97% mortality) based on WHO results interpretation. Significantly elevated (P<0.05) activities of GST, esterase and monooxygenase were recorded in deltamethrin and bendiocarb resistant strains compared to susceptible species in both BA and BR. The finding of the study established high resistance status to deltamethrin and incipient resistance to bendiocarb in all the study sites which could be linked to indiscriminate use of insecticides in residential sites against malarial vector and other flying insects and agrochemicals for pest control in the agricultural sites. Based on this finding, it may be concluded that insecticides resistance to malaria vector exists in both residential and agricultural areas and measures should be taken to curtail it.Keywords: insecticides (deltamethrin and bendiocarb) resistance, Bioassay, Malarial vector, detoxification enzymes

Some haematological parameters of inter-generic hybrid of African catfish (Clarias anguillaris x Heterobranchus bidorsallis) juveniles and their pure lines in north eastern Nigeria

Some haematological parameters of inter-generic hybrid African catfish (Clarias anguillaris x Heterobranchus bidorsalis) were investigated to assess the ability of the hybrids to withstand culture conditions in North East Nigeria. The result shows that packed cell volume (PCV), red blood cells (RBC), Haemoglobin (Hb), mean cell haemoglobin concentration (MCHC) and platelets (PLT) were higher in pure line Clarias anguillaris. However, white blood cell (WBC) and lymphocytes (LYM) were higher in female H. bidorsalis x male C. anguillaris (Heteroclarias) hybrid. PCV, MCHC, Hb, and RBC of all the fish species observed in this study were within the healthy ranges for fish. The results of this study shows that Heteroclarias have haematological competence for survival in culture conditions in the region

Insect and vertebrate pests associated with cultivated field pea (Pisum Sativum linn) in Northern Guinea Savanna of Nigeria

Pisum sativum commonly called field pea (Family; Fabaceae). The aim of this study was to determine the incidence and identify pests of field pea in major growing areas of Nigeria. The larval stages of the insect were collected from different field pea farms in Northern Guinea Savanna of Nigeria (Shika dam, Katanga and Zangon Danbarno, Sabuwa, Rapiyan fan in Barkin Ladi and Razek fan). The percentage incidence of pest’s infestation was calculated for each sampling location. Identification of the pests was done using identification keys. Shika dam has the highest percentage incidence of insects with 60 % followed by Katanga, Zangon Danbarno and Rapiyam fan with 20 % while Razek fan has 15 %. Sabuwa has the least with 10 %. A total of six insect pests were identified from the six different sampling locations (Spodoptera exigua Hwan, Spodoptera exempta Walk, Heliocoverpa armigera Hubn, Etiella zinckenella Trerischk, Tetranychus urticae and Caliothrips sp.) and one mammal (Rattus sp.). All the insect pests are more devastating at seedling stage; however, Tetranychus sp. and Caliothrips sp. proceed up to podding stage. Farmers are advised to practice sole cropping and avoid intercropping with susceptible hosts. Keywords: Pisum sativum, Pest

Preparation and characterization of nanocrystalline Ba(Ti0.96SnxZr0.04-x)O3 ceramic

Nanocrystalline powders of Barium titanate (BaTiO3 or BT) and Ba(Ti0.96SnxZr0.04-x)O3 (BTSZ1, BTSZ2, and BTSZ3) [x=0.02, 0.03 and 0.04] have been synthesized by a combination of solid-state reaction and high energy ball- milling technique (HBM). The effect of increasing Sn content on the microstructure and dielectric properties of the ceramics were studied. X-ray diffraction patterns show cubic and tetragonal symmetry without secondary phase. Sn4+ and Zr4+ ions entered the perovskite-type cubic structure and led to an increase in the lattice parameters. The average crystallite size has been calculated using Scherrer formula. Using Scherrer, the crystallite size of the (110) peaks of the pure BT is 31.2 nm and that of BTSZ1, BTSZ2, and BTSZ3 are 42.7, 37.9 and 42.3 nm respectively. The FESEM results indicated a variation of grain size from 144.53, to 89.28 nm for the pure BT, BTSZ1, BTSZ2, and BTSZ3, which show a decrease in grain size as Sn doping increases. Frequency dependence of dielectric permittivity and loss studied in the range temperature and frequency range 30-400oC and 40 Hz–1 MHz, respectively, for BT, BTSZ1, BTSZ2, and BTSZ3 show a normal ferroelectric phase transition behavior. The corresponding dielectric constant and loss at room temperature show that BTSZ2 has the highest dielectric constant and loss of 1671 and 1.6 respectively. The high dielectric constants and relatively lower loss tangent values meet the current demand for device miniaturization in the electronics industry.Keywords: BT-BTSZ ceramics; high energy ball milling; XRD; FESEM; dielectric propertie

Characteristics of horizontal gas-liquid two-phase flow measurement in a medium-sized pipe using gamma densitometry

Two-phase flows are common occurrences in many industrial applications. The understanding of their characteristics in industrial piping systems is vital for the efficient design, optimization, and operation of industrial processes. Most of the previous experimental studies involving the use of gamma densitometers for holdup measurements in air-water mixtures are limited to smaller diameter pipes (generally regarded as those with < 50 mm in nominal diameter). Further, very few literature report experimental data obtained using gamma desitometers. This paper presents an application of a gamma densitometer in the measurement of two-phase flow characteristics in an intermediate diameter pipe (nominal diameter between 50 mm and 100 mm). Scaled air-water experiments were performed in a 17-m long, 0.0764-m internal diameter horizontal pipe. Liquid superficial velocity ranged between 0.1–0.4 m/s while gas superficial velocity ranged from 0.3 to 10.0 m/s. The measured parameters include liquid holdup, pressure gradient, flow pattern, and slug flow features. The flow patterns observed were stratified, stratified-wavy, plug, slug, and annular flows. Plug and slug flow patterns showed good agreement with established flow pattern maps. Furthermore, the slug translational velocity was observed to increase with increasing mixture velocity, as reported by previous authors, hence establishing the reliability of the instrumentation employed. The slug body length was also measured using the gamma densitometer and was found to be within the range 24–36D with a mean length of 30.6D

The Dynamics of Land Use Land Cover Change: Using Geospatial Techniques to Promote Sustainable Urban Development in Ilorin Metropolis, Nigeria

Land change dynamics was studied and analyzed across the plains of Metropolitan Ilorin between 1986 and 2010. A statistical sampling design, Landsat satellite data and Geographical Information System tools were used to efficiently identify patterns of land conversion. Variability of change ranged from approximately 2 percent to greater than 50 percent, and progressed at an uneven pace. Indicative of the changes is a sequence of agricultural expansion before 1986 followed by widespread conversion to built up area by 2000 and beyond. Pattern and magnitude of conversions influenced by contextual conditions of land quality, population increase, plus economic and policy drivers. The sporadic expansion of settlements, especially the built up areas in and around the study area, resulted in rapid diminishing and conversion of other land cover types to more built up environment and thus aaccentuating urban agglomeration of Ilorin. It is recommended that various Government regulatory authorities embark on careful urban planning by strickly allocating land for various designated purposes and ensure continous monitoring of physical developments so as to safeguard distortions to the urban environment of Ilorin

Global, regional, and national comparative risk assessment of 79 behavioural, environmental and occupational, and metabolic risks or clusters of risks, 1990-2015: A systematic analysis for the Global Burden of Disease Study 2015

Background: The Global Burden of Diseases, Injuries, and Risk Factors Study 2015 provides an up-to-date synthesis of the evidence for risk factor exposure and the attributable burden of disease. By providing national and subnational assessments spanning the past 25 years, this study can inform debates on the importance of addressing risks in context. Methods: We used the comparative risk assessment framework developed for previous iterations of the Global Burden of Disease Study to estimate attributable deaths, disability-adjusted life-years (DALYs), and trends in exposure by age group, sex, year, and geography for 79 behavioural, environmental and occupational, and metabolic risks or clusters of risks from 1990 to 2015. This study included 388 risk-outcome pairs that met World Cancer Research Fund-defined criteria for convincing or probable evidence. We extracted relative risk and exposure estimates from randomised controlled trials, cohorts, pooled cohorts, household surveys, census data, satellite data, and other sources. We used statistical models to pool data, adjust for bias, and incorporate covariates. We developed a metric that allows comparisons of exposure across risk factors—the summary exposure value. Using the counterfactual scenario of theoretical minimum risk level, we estimated the portion of deaths and DALYs that could be attributed to a given risk. We decomposed trends in attributable burden into contributions from population growth, population age structure, risk exposure, and risk-deleted cause-specific DALY rates. We characterised risk exposure in relation to a Socio-demographic Index (SDI). Findings: Between 1990 and 2015, global exposure to unsafe sanitation, household air pollution, childhood underweight, childhood stunting, and smoking each decreased by more than 25%. Global exposure for several occupational risks, high body-mass index (BMI), and drug use increased by more than 25% over the same period. All risks jointly evaluated in 2015 accounted for 57·8% (95% CI 56·6–58·8) of global deaths and 41·2% (39·8–42·8) of DALYs. In 2015, the ten largest contributors to global DALYs among Level 3 risks were high systolic blood pressure (211·8 million [192·7 million to 231·1 million] global DALYs), smoking (148·6 million [134·2 million to 163·1 million]), high fasting plasma glucose (143·1 million [125·1 million to 163·5 million]), high BMI (120·1 million [83·8 million to 158·4 million]), childhood undernutrition (113·3 million [103·9 million to 123·4 million]), ambient particulate matter (103·1 million [90·8 million to 115·1 million]), high total cholesterol (88·7 million [74·6 million to 105·7 million]), household air pollution (85·6 million [66·7 million to 106·1 million]), alcohol use (85·0 million [77·2 million to 93·0 million]), and diets high in sodium (83·0 million [49·3 million to 127·5 million]). From 1990 to 2015, attributable DALYs declined for micronutrient deficiencies, childhood undernutrition, unsafe sanitation and water, and household air pollution; reductions in risk-deleted DALY rates rather than reductions in exposure drove these declines. Rising exposure contributed to notable increases in attributable DALYs from high BMI, high fasting plasma glucose, occupational carcinogens, and drug use. Environmental risks and childhood undernutrition declined steadily with SDI; low physical activity, high BMI, and high fasting plasma glucose increased with SDI. In 119 countries, metabolic risks, such as high BMI and fasting plasma glucose, contributed the most attributable DALYs in 2015. Regionally, smoking still ranked among the leading five risk factors for attributable DALYs in 109 countries; childhood underweight and unsafe sex remained primary drivers of early death and disability in much of sub-Saharan Africa. Interpretation: Declines in some key environmental risks have contributed to declines in critical infectious diseases. Some risks appear to be invariant to SDI. Increasing risks, including high BMI, high fasting plasma glucose, drug use, and some occupational exposures, contribute to rising burden from some conditions, but also provide opportunities for intervention. Some highly preventable risks, such as smoking, remain major causes of attributable DALYs, even as exposure is declining. Public policy makers need to pay attention to the risks that are increasingly major contributors to global burden. Funding: Bill & Melinda Gates Foundation

Reducing the environmental impact of surgery on a global scale: systematic review and co-prioritization with healthcare workers in 132 countries

Background Healthcare cannot achieve net-zero carbon without addressing operating theatres. The aim of this study was to prioritize feasible interventions to reduce the environmental impact of operating theatres. Methods This study adopted a four-phase Delphi consensus co-prioritization methodology. In phase 1, a systematic review of published interventions and global consultation of perioperative healthcare professionals were used to longlist interventions. In phase 2, iterative thematic analysis consolidated comparable interventions into a shortlist. In phase 3, the shortlist was co-prioritized based on patient and clinician views on acceptability, feasibility, and safety. In phase 4, ranked lists of interventions were presented by their relevance to high-income countries and low–middle-income countries. Results In phase 1, 43 interventions were identified, which had low uptake in practice according to 3042 professionals globally. In phase 2, a shortlist of 15 intervention domains was generated. In phase 3, interventions were deemed acceptable for more than 90 per cent of patients except for reducing general anaesthesia (84 per cent) and re-sterilization of ‘single-use’ consumables (86 per cent). In phase 4, the top three shortlisted interventions for high-income countries were: introducing recycling; reducing use of anaesthetic gases; and appropriate clinical waste processing. In phase 4, the top three shortlisted interventions for low–middle-income countries were: introducing reusable surgical devices; reducing use of consumables; and reducing the use of general anaesthesia. Conclusion This is a step toward environmentally sustainable operating environments with actionable interventions applicable to both high– and low–middle–income countries

Global burden and strength of evidence for 88 risk factors in 204 countries and 811 subnational locations, 1990–2021: a systematic analysis for the Global Burden of Disease Study 2021

Background: Understanding the health consequences associated with exposure to risk factors is necessary to inform public health policy and practice. To systematically quantify the contributions of risk factor exposures to specific health outcomes, the Global Burden of Diseases, Injuries, and Risk Factors Study (GBD) 2021 aims to provide comprehensive estimates of exposure levels, relative health risks, and attributable burden of disease for 88 risk factors in 204 countries and territories and 811 subnational locations, from 1990 to 2021. Methods: The GBD 2021 risk factor analysis used data from 54 561 total distinct sources to produce epidemiological estimates for 88 risk factors and their associated health outcomes for a total of 631 risk–outcome pairs. Pairs were included on the basis of data-driven determination of a risk–outcome association. Age-sex-location-year-specific estimates were generated at global, regional, and national levels. Our approach followed the comparative risk assessment framework predicated on a causal web of hierarchically organised, potentially combinative, modifiable risks. Relative risks (RRs) of a given outcome occurring as a function of risk factor exposure were estimated separately for each risk–outcome pair, and summary exposure values (SEVs), representing risk-weighted exposure prevalence, and theoretical minimum risk exposure levels (TMRELs) were estimated for each risk factor. These estimates were used to calculate the population attributable fraction (PAF; ie, the proportional change in health risk that would occur if exposure to a risk factor were reduced to the TMREL). The product of PAFs and disease burden associated with a given outcome, measured in disability-adjusted life-years (DALYs), yielded measures of attributable burden (ie, the proportion of total disease burden attributable to a particular risk factor or combination of risk factors). Adjustments for mediation were applied to account for relationships involving risk factors that act indirectly on outcomes via intermediate risks. Attributable burden estimates were stratified by Socio-demographic Index (SDI) quintile and presented as counts, age-standardised rates, and rankings. To complement estimates of RR and attributable burden, newly developed burden of proof risk function (BPRF) methods were applied to yield supplementary, conservative interpretations of risk–outcome associations based on the consistency of underlying evidence, accounting for unexplained heterogeneity between input data from different studies. Estimates reported represent the mean value across 500 draws from the estimate's distribution, with 95% uncertainty intervals (UIs) calculated as the 2·5th and 97·5th percentile values across the draws. Findings: Among the specific risk factors analysed for this study, particulate matter air pollution was the leading contributor to the global disease burden in 2021, contributing 8·0% (95% UI 6·7–9·4) of total DALYs, followed by high systolic blood pressure (SBP; 7·8% [6·4–9·2]), smoking (5·7% [4·7–6·8]), low birthweight and short gestation (5·6% [4·8–6·3]), and high fasting plasma glucose (FPG; 5·4% [4·8–6·0]). For younger demographics (ie, those aged 0–4 years and 5–14 years), risks such as low birthweight and short gestation and unsafe water, sanitation, and handwashing (WaSH) were among the leading risk factors, while for older age groups, metabolic risks such as high SBP, high body-mass index (BMI), high FPG, and high LDL cholesterol had a greater impact. From 2000 to 2021, there was an observable shift in global health challenges, marked by a decline in the number of all-age DALYs broadly attributable to behavioural risks (decrease of 20·7% [13·9–27·7]) and environmental and occupational risks (decrease of 22·0% [15·5–28·8]), coupled with a 49·4% (42·3–56·9) increase in DALYs attributable to metabolic risks, all reflecting ageing populations and changing lifestyles on a global scale. Age-standardised global DALY rates attributable to high BMI and high FPG rose considerably (15·7% [9·9–21·7] for high BMI and 7·9% [3·3–12·9] for high FPG) over this period, with exposure to these risks increasing annually at rates of 1·8% (1·6–1·9) for high BMI and 1·3% (1·1–1·5) for high FPG. By contrast, the global risk-attributable burden and exposure to many other risk factors declined, notably for risks such as child growth failure and unsafe water source, with age-standardised attributable DALYs decreasing by 71·5% (64·4–78·8) for child growth failure and 66·3% (60·2–72·0) for unsafe water source. We separated risk factors into three groups according to trajectory over time: those with a decreasing attributable burden, due largely to declining risk exposure (eg, diet high in trans-fat and household air pollution) but also to proportionally smaller child and youth populations (eg, child and maternal malnutrition); those for which the burden increased moderately in spite of declining risk exposure, due largely to population ageing (eg, smoking); and those for which the burden increased considerably due to both increasing risk exposure and population ageing (eg, ambient particulate matter air pollution, high BMI, high FPG, and high SBP). Interpretation: Substantial progress has been made in reducing the global disease burden attributable to a range of risk factors, particularly those related to maternal and child health, WaSH, and household air pollution. Maintaining efforts to minimise the impact of these risk factors, especially in low SDI locations, is necessary to sustain progress. Successes in moderating the smoking-related burden by reducing risk exposure highlight the need to advance policies that reduce exposure to other leading risk factors such as ambient particulate matter air pollution and high SBP. Troubling increases in high FPG, high BMI, and other risk factors related to obesity and metabolic syndrome indicate an urgent need to identify and implement interventions. Funding: Bill & Melinda Gates Foundation

Estimates of global, regional, and national incidence, prevalence, and mortality of HIV, 1980�2015: the Global Burden of Disease Study 2015

Background Timely assessment of the burden of HIV/AIDS is essential for policy setting and programme evaluation. In this report from the Global Burden of Disease Study 2015 (GBD 2015), we provide national estimates of levels and trends of HIV/AIDS incidence, prevalence, coverage of antiretroviral therapy (ART), and mortality for 195 countries and territories from 1980 to 2015. Methods For countries without high-quality vital registration data, we estimated prevalence and incidence with data from antenatal care clinics and population-based seroprevalence surveys, and with assumptions by age and sex on initial CD4 distribution at infection, CD4 progression rates (probability of progression from higher to lower CD4 cell-count category), on and off antiretroviral therapy (ART) mortality, and mortality from all other causes. Our estimation strategy links the GBD 2015 assessment of all-cause mortality and estimation of incidence and prevalence so that for each draw from the uncertainty distribution all assumptions used in each step are internally consistent. We estimated incidence, prevalence, and death with GBD versions of the Estimation and Projection Package (EPP) and Spectrum software originally developed by the Joint United Nations Programme on HIV/AIDS (UNAIDS). We used an open-source version of EPP and recoded Spectrum for speed, and used updated assumptions from systematic reviews of the literature and GBD demographic data. For countries with high-quality vital registration data, we developed the cohort incidence bias adjustment model to estimate HIV incidence and prevalence largely from the number of deaths caused by HIV recorded in cause-of-death statistics. We corrected these statistics for garbage coding and HIV misclassification. Findings Global HIV incidence reached its peak in 1997, at 3·3 million new infections (95 uncertainty interval UI 3·1�3·4 million). Annual incidence has stayed relatively constant at about 2·6 million per year (range 2·5�2·8 million) since 2005, after a period of fast decline between 1997 and 2005. The number of people living with HIV/AIDS has been steadily increasing and reached 38·8 million (95% UI 37·6�40·4 million) in 2015. At the same time, HIV/AIDS mortality has been declining at a steady pace, from a peak of 1·8 million deaths (95% UI 1·7�1·9 million) in 2005, to 1·2 million deaths (1·1�1·3 million) in 2015. We recorded substantial heterogeneity in the levels and trends of HIV/AIDS across countries. Although many countries have experienced decreases in HIV/AIDS mortality and in annual new infections, other countries have had slowdowns or increases in rates of change in annual new infections. Interpretation Scale-up of ART and prevention of mother-to-child transmission has been one of the great successes of global health in the past two decades. However, in the past decade, progress in reducing new infections has been slow, development assistance for health devoted to HIV has stagnated, and resources for health in low-income countries have grown slowly. Achievement of the new ambitious goals for HIV enshrined in Sustainable Development Goal 3 and the 90-90-90 UNAIDS targets will be challenging, and will need continued efforts from governments and international agencies in the next 15 years to end AIDS by 2030. Funding Bill & Melinda Gates Foundation, and National Institute of Mental Health and National Institute on Aging, National Institutes of Health. © 2016 The Author(s). Published by Elsevier Ltd. This is an Open Access article under the CC BY licens