The Use of Fibre Waste as Complement in Concrete for a Sustainable Environment

One of the many challenges faced in developing world is the issue of waste management. Organic fibres forms major percentage of waste produced from agricultural products and should be of great concern. Fibres have been used to reinforce composites concrete to obtain lighter weight, reduce shrinkage effects which serve to reduce environmental waste. Natural fibre is 100% bio-degradable and recyclable, thereby eliminate pollution, promote biodiversity and conservation of natural resources and thus environmentally friendly.This paper focuses on utilization of some fibres as solid wastes for making economically-friendly and affordable green environment. Three fibres: Jute, Oil palm and Polypropylene fibres were used as complement in concrete and its suitability, durability and influence on the properties of concrete were assessed. The percentages of fibre used were 0.25 and 0.5 of cement content by weight. A total of 84 concrete cube specimens were prepared for standard tests which include compression test, slump test and compaction factor test. The compression test was carried out at concrete ages of 7, 14, 21 and 28 days. As the percentage of the fibre increases, the tendency for fibre to ball up becomes higher in water. The test results showed that for Jute and Oil palm fibres, the optimum fibre content was 0.25% and for Polypropylene fibre, the optimum fibre content was 0.5%. They all yielded increase in strength when compared to the control specimen and has proven to reduce reasonable environmental waste pollution. Keywords: Environmental Pollution, Fibre, Concrete strength, Jute, Waste reductio

Strength and Workability Improvement Potential of Admixture of Corn Cob Ash and Cement for Stabilizing Lateritic Soil

A natural lateritic soil classified as A-7-5 (10) and CL based on AASHTO and USCS classification systems, was stabilized with up to 5% cement admixed with up to 12% CCA to assess their effect on its basic geotechnical properties such as particle size distribution, Atterberg limits, compaction, unconfined compressive strength and California bearing ratio. The liquid limit decreased and plastic limit increased while there is a reduction in corresponding plasticity index of the clay soil. There was an increase in Maximum Dry Density (MDD) and Optimum Moisture Content (OMC) of the stabilized soil sample, which increased with the increasing content of CCA and cement. Both the Unconfined Compressive Strength (UCS) and California Bearing Ratio (CBR) of the soil increased with increasing percentage of cement and CCA. Based on the results of this study, corn cob ash (CCA) cannot be used as a stand-alone stabilizer for this lateritic soil but with a more potent stabilizer for clay soil such as lime. It is therefore recommended that the mixture of 12% CCA and 2.5% cement could be used to stabilize A-7-5 (10) lateritic soil for use as subbase material and 12% CCA and 5.0% cement could be used to stabilize A-7-5 (10) lateritic soil for use as base material for improving pavement structure in terms of strength, stability and workability. Keywords: Lateritic soil, Corn cob ash, Cement, Stabilization, Strength and Workability DOI: 10.7176/JIEA/9-7-06 Publication date: December 31st 201

THE COMBINED EFFECTS OF SOIL, WATER AND SURCHARGE LOADS ON THE STRUCTURAL BEHAVIOURS OF CANTILEVER RETAINING WALL

Retaining walls are engineering structures constructed to resist lateral forces imposed by soil movement and water pressure; they are used as protection against the erosive forces of water and as a method of slope stabilization along highways, railroads and construction sites. This Study modeled the combined effects of soil, Surcharge loads and Hydrostatic pressure on the structural behaviours of cantilever retaining wall under varying geometric conditions. The limit state requirements for overturning, sliding and bearing pressure were studied under different geometric properties. The use of computer programming (Java) was employed for quick analyses of the conditions. This research therefore minimized the stress associated with the iterative process of design and analyses of these structures. The deductions gave range of satisfactory dimensions with respect to the height of the wall for the preliminary dimensioning state of design. This study also answered the remained unanswered question of the effects of an increasing load being supported by retaining wall. The results revealed that Cantilever retaining wall will perform satisfactorily based on the factors of safety of and as against sliding and overturning respectively if soil is ignored in front of the wall with following values of Base width: For wall supporting full submerged soil, the Base width, ; wall supporting submerge soil up to 0.6 of its Height, Base width,   and for wall with submerge soil up to 0.2 of wall height, Base width, . Results also showed that safety factors against sliding and overturning increase at a decreasing rate with constant decrease in water level. This gives an indication that water level greatly affects the stability of the retaining wall, that is, the higher the water level the greater the sliding and overturning effects. Results also revealed that sliding safety factor increases constantly with Base width while factor of safety against overturning increases at an increasing rate. This also shows the severity of sliding as against overturning. Both safety factors also increase at a decreasing rate with Wall height giving an indication that the stability of cantilever retaining wall increases with its Height under the same load. For an increasing surcharge values, sliding safety factor decreases constantly while overturning decreases at a decreasing rate. This also explains why overturning is less critical as compared to sliding effect

PILOT STUDY ON LOW COST DOMESTIC SLOW SAND FILTER FOR GROUNDWATER QUALITY IMPROVEMENT

Most waterborne diseases can be prevented using simple, low cost water filtration techniques. The aim of this study is to design a low cost domestic slow sand filter, which can be operated and maintained effectiveness at household level by a member of the family, and determine its effectiveness in removing selected contaminants from the raw groundwater. Fine sand, activated charcoal, coarse sand, and gravel were used as media column for the developed slow sand filtration media. Common selected physico-chemical and microbial water parameters were examined before and after filtration with the slow sand filtration system. The filter was able to remove turbidity of the raw groundwater in the range of 86 - 92% without hampering the pH value or the temperature below the acceptable standards set by the Nigerian standards for drinking water quality. The filter media was able to reduce an average of 44 - 82%, 29 - 53% and 60 – 66% of total hardness, calcium hardness and chloride content, respectively from the chemical composition of the groundwater samples.  The media also showed high effectiveness in reducing biological impurities from the groundwater.  It was able to remove effectively the concentration of E-Coli and coliform counts. The average percent removal of E-coli and coliforms was found to be 100%. These were achieved with the aid of the bio-film layer that developed on the topmost part (fine sand layer) of the filter which was able to predate on the microbes in the groundwater samples. Slow sand filters are a sustainable means of water treatment when applied to appropriate source waters and when designed and operated properly.&nbsp

SUSTAINABLE MANAGEMENT OF COW DUNG FROM SLAUGHTER HOUSES

Large amount of cattle dung are generated daily from slaughter houses which are not only of environmental concern due to methane emission but also present a significant health risk if not adequately managed.  In this study, cow dung obtained from slaughter house was anaerobically digested and its composition evaluated.8 kg of the collected cow dung was mixed with water using a mechanical stirrer set at a speed of 150 rpm to form slurry before pouring it into a laboratory scale digester affixed with stirrer, inlet and outlet ports and temperature detector. The set up was left for 3days for microbial activation to take place, before daily stirring.  Average weekly temperature of the slurry inside the digester tank was observed. Biogas produced was collected in a rubber tube and trapped with activated charcoal dissolved in 500 ml of carbon disulphide (CS2) for 120 minutes in an open air. The liquid filtrate was then analysed using a Gas Chromatography. The optimum temperature was observed at 36.5 OC. The digestion temperature variation was between 0.5 to 2 OC. Methane bacteria worked best in the temperature ranges between 34 and 37 OC. After the liquefaction process, 30 cm3 of biogas was generated. Out of which, methane occupied 25.002 cm3 (83.34 %), carbon dioxide 4.467 cm3 (14.89 %), nitrogen 0.468cm3 (1.56 %) while carbon monoxide generated was 0.063 cm3 (0.21 %). The result clearly show that methane has the highest yield, the energy contained in methane can be used as domestic gas.Cow dung is an excellent substrate for biogas production in anaerobic digesters instead of indiscriminate disposal. Bio-digestion of cow dung is a viable and sustainable solution to the problem of waste pollution, disposal, control and management

Accumulation of Protease Mutations among Patients Failing Second-Line Antiretroviral Therapy and Response to Salvage Therapy in Nigeria

Background: To date, antiretroviral therapy (ART) guidelines and programs in resource-limited settings (RLS) have focused on 1st- and 2nd-line (2 L) therapy. As programs approach a decade of implementation, policy regarding access to 3rd-line (3 L) ART is needed. We aimed to examine the impact of maintaining patients on failing 2 L ART on the accumulation of protease (PR) mutations. Methods and Findings: From 2004–2011, the Harvard/APIN PEPFAR Program provided ART to >100,000 people in Nigeria. Genotypic resistance testing was performed on a subset of patients experiencing 2 L failure, defined as 2 consecutive viral loads (VL)>1000 copies/mL after ≥6 months on 2 L. Of 6714 patients who received protease inhibitor (PI)-based ART, 673 (10.0%) met virologic failure criteria. Genotypes were performed on 61 samples. Patients on non-suppressive 2 L therapy for 24 months. Patients developed a median of 0.6 (IQR: 0–1.4) IAS PR mutations per 6 months on failing 2 L therapy. In 38% of failing patients no PR mutations were present. For patients failing >24 months, high- or intermediate-level resistance to lopinavir and atazanavir was present in 63%, with 5% to darunavir. Conclusions: This is the first report assessing the impact of duration of non-suppressive 2 L therapy on the accumulation of PR resistance in a RLS. This information provides insight into the resistance cost of failing to switch non-suppressive 2 L regimens and highlights the issue of 3 L access

Large expert-curated database for benchmarking document similarity detection in biomedical literature search

Document recommendation systems for locating relevant literature have mostly relied on methods developed a decade ago. This is largely due to the lack of a large offline gold-standard benchmark of relevant documents that cover a variety of research fields such that newly developed literature search techniques can be compared, improved and translated into practice. To overcome this bottleneck, we have established the RElevant LIterature SearcH consortium consisting of more than 1500 scientists from 84 countries, who have collectively annotated the relevance of over 180 000 PubMed-listed articles with regard to their respective seed (input) article/s. The majority of annotations were contributed by highly experienced, original authors of the seed articles. The collected data cover 76% of all unique PubMed Medical Subject Headings descriptors. No systematic biases were observed across different experience levels, research fields or time spent on annotations. More importantly, annotations of the same document pairs contributed by different scientists were highly concordant. We further show that the three representative baseline methods used to generate recommended articles for evaluation (Okapi Best Matching 25, Term Frequency-Inverse Document Frequency and PubMed Related Articles) had similar overall performances. Additionally, we found that these methods each tend to produce distinct collections of recommended articles, suggesting that a hybrid method may be required to completely capture all relevant articles. The established database server located at https://relishdb.ict.griffith.edu.au is freely available for the downloading of annotation data and the blind testing of new methods. We expect that this benchmark will be useful for stimulating the development of new powerful techniques for title and title/abstract-based search engines for relevant articles in biomedical research.Peer reviewe

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

Forouzanfar MH, Afshin A, Alexander LT, et al. 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. LANCET. 2016;388(10053):1659-1724.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. Copyright (C) The Author(s). Published by Elsevier Ltd

Global, regional, and national life expectancy, all-cause mortality, and cause-specific mortality for 249 causes of death, 1980-2015 : a systematic analysis for the Global Burden of Disease Study 2015

Background Improving survival and extending the longevity of life for all populations requires timely, robust evidence on local mortality levels and trends. The Global Burden of Disease 2015 Study (GBD 2015) provides a comprehensive assessment of all-cause and cause-specific mortality for 249 causes in 195 countries and territories from 1980 to 2015. These results informed an in-depth investigation of observed and expected mortality patterns based on sociodemographic measures. Methods We estimated all-cause mortality by age, sex, geography, and year using an improved analytical approach originally developed for GBD 2013 and GBD 2010. Improvements included refinements to the estimation of child and adult mortality and corresponding uncertainty, parameter selection for under-5 mortality synthesis by spatiotemporal Gaussian process regression, and sibling history data processing. We also expanded the database of vital registration, survey, and census data to 14 294 geography-year datapoints. For GBD 2015, eight causes, including Ebola virus disease, were added to the previous GBD cause list for mortality. We used six modelling approaches to assess cause-specific mortality, with the Cause of Death Ensemble Model (CODEm) generating estimates for most causes. We used a series of novel analyses to systematically quantify the drivers of trends in mortality across geographies. First, we assessed observed and expected levels and trends of cause-specific mortality as they relate to the Socio-demographic Index (SDI), a summary indicator derived from measures of income per capita, educational attainment, and fertility. Second, we examined factors affecting total mortality patterns through a series of counterfactual scenarios, testing the magnitude by which population growth, population age structures, and epidemiological changes contributed to shifts in mortality. Finally, we attributed changes in life expectancy to changes in cause of death. We documented each step of the GBD 2015 estimation processes, as well as data sources, in accordance with Guidelines for Accurate and Transparent Health Estimates Reporting (GATHER). Findings Globally, life expectancy from birth increased from 61.7 years (95% uncertainty interval 61.4-61.9) in 1980 to 71.8 years (71.5-72.2) in 2015. Several countries in sub-Saharan Africa had very large gains in life expectancy from 2005 to 2015, rebounding from an era of exceedingly high loss of life due to HIV/AIDS. At the same time, many geographies saw life expectancy stagnate or decline, particularly for men and in countries with rising mortality from war or interpersonal violence. From 2005 to 2015, male life expectancy in Syria dropped by 11.3 years (3.7-17.4), to 62.6 years (56.5-70.2). Total deaths increased by 4.1% (2.6-5.6) from 2005 to 2015, rising to 55.8 million (54.9 million to 56.6 million) in 2015, but age-standardised death rates fell by 17.0% (15.8-18.1) during this time, underscoring changes in population growth and shifts in global age structures. The result was similar for non-communicable diseases (NCDs), with total deaths from these causes increasing by 14.1% (12.6-16.0) to 39.8 million (39.2 million to 40.5 million) in 2015, whereas age-standardised rates decreased by 13.1% (11.9-14.3). Globally, this mortality pattern emerged for several NCDs, including several types of cancer, ischaemic heart disease, cirrhosis, and Alzheimer's disease and other dementias. By contrast, both total deaths and age-standardised death rates due to communicable, maternal, neonatal, and nutritional conditions significantly declined from 2005 to 2015, gains largely attributable to decreases in mortality rates due to HIV/AIDS (42.1%, 39.1-44.6), malaria (43.1%, 34.7-51.8), neonatal preterm birth complications (29.8%, 24.8-34.9), and maternal disorders (29.1%, 19.3-37.1). Progress was slower for several causes, such as lower respiratory infections and nutritional deficiencies, whereas deaths increased for others, including dengue and drug use disorders. Age-standardised death rates due to injuries significantly declined from 2005 to 2015, yet interpersonal violence and war claimed increasingly more lives in some regions, particularly in the Middle East. In 2015, rotaviral enteritis (rotavirus) was the leading cause of under-5 deaths due to diarrhoea (146 000 deaths, 118 000-183 000) and pneumococcal pneumonia was the leading cause of under-5 deaths due to lower respiratory infections (393 000 deaths, 228 000-532 000), although pathogen-specific mortality varied by region. Globally, the effects of population growth, ageing, and changes in age-standardised death rates substantially differed by cause. Our analyses on the expected associations between cause-specific mortality and SDI show the regular shifts in cause of death composition and population age structure with rising SDI. Country patterns of premature mortality (measured as years of life lost [YLLs]) and how they differ from the level expected on the basis of SDI alone revealed distinct but highly heterogeneous patterns by region and country or territory. Ischaemic heart disease, stroke, and diabetes were among the leading causes of YLLs in most regions, but in many cases, intraregional results sharply diverged for ratios of observed and expected YLLs based on SDI. Communicable, maternal, neonatal, and nutritional diseases caused the most YLLs throughout sub-Saharan Africa, with observed YLLs far exceeding expected YLLs for countries in which malaria or HIV/AIDS remained the leading causes of early death. Interpretation At the global scale, age-specific mortality has steadily improved over the past 35 years; this pattern of general progress continued in the past decade. Progress has been faster in most countries than expected on the basis of development measured by the SDI. Against this background of progress, some countries have seen falls in life expectancy, and age-standardised death rates for some causes are increasing. Despite progress in reducing age-standardised death rates, population growth and ageing mean that the number of deaths from most non-communicable causes are increasing in most countries, putting increased demands on health systems. Copyright (C) The Author(s). Published by Elsevier Ltd.Peer reviewe