Trace metals -- a potential threat to our fishing industry

Trace metals constitute a major form of water pollutant that can adversely affect fish production. The potentially toxic metals have been identified as lead, zinc, copper, arsenic, antimony, mercury beryllium, barium, cadmium, chromium, nickel, selenium among others. Preliminary laboratory studies have been directed to the determination of traces of lead in the aquatic biota and its toxicity. There are indications that the levels reported in effluents from some of the industries may be above the tolerant limits of local fish species and organisms that make up their food. Metal pollution could become a serious problem to freshwater fisheries in the future as a result of increasing urbanization and industrialization, unless efforts are made to prevent i

Preliminary studies on the effects of varying levels of aeration on the growth and physiological processes of cultured Clarias gariepinus fingerlings

To determine the aeration regime and the resultant dissolved oxygen input that imposes the least physiological stress on homeostatic mechanisms of C. gariepinus fingerlings, were culture in the laboratory under 24 hours of continuous aeration and inputing a mean of 8.2 mg/l of 02; 12 hours of aeration (mean of 4.6mgO/l2); and zero-aeration (mean of 1.2 mgO/l2)' Survival rate, growth rate and mean weight gain per day were highest in the 4.6 mgO/l2 culture whereas, the other two cultures were characterized by higher mortality rates and insignificant growth rates. The haematological profile analyzed showed varying degrees of changes in the blood parameters of the fish cultured under varying levels of aeration and their inputed dissolved oxygen levels

Synthesis, physicochemical and antimicrobial properties of Co (II) and Ni (II) metal complexes of the Schiff base of isatin and 4-methylaniline

Schiff bases derived from isatin are of great importance due to their wide applications as synthetic precursors and biological applications. The Schiff base of isatin and 4-methylaniline (C15H12N2O; L) was prepared by stirring at room temperature (using ratio 1:1) in methanol. Co (CH3COO)2.4H20 and Ni(CH3COO)2.4H2O were separately refluxed with the Schiff base (Metal:Ligand = 1:3) in toluene to give their respective metal complexes. Physicochemical properties of the prepared compounds were determined using Infra-red and Electronic Spectra analyses, as well as melting point determinations. The in-vitro antimicrobial activities of L and its metal complexes were evaluated against three Gram positive bacteria (Enterococcus faecalis, Micrococcus luteus and Staphylococcus aureus) and three Gram negative bacteria (Escherichia coli, Salmonella typhi and Pseudomonas aeruginosa). They showed more activities against the tested Gram positive bacteria than the Gram negative bacteria. The minimum inhibitory concentration (MIC) of Co (II) and Ni(II) complexes was 5μg/mL, while that of L was 2.5μg/mL. All the test bacteria were susceptible to the compounds except S. aureus and E. coli. The synthesized compounds also had antifungal potentials.Keywords: Isatin,4-methylaniline, Schiff base, Co(II), Ni(II) metal complexe

Chemical characterisation of palm kernel (Elaeis guineensis Jacq.), shea butter (Vitellaria paradoxa C.F. Gaertn.) and sesame (Sesamum indicum L.) seed oils as ingredients in breeding broiler diets

Lipids are important to both humans and livestock where they play important role as an excellent source of energy and enhances the absorption of fat-soluble vitamins. However, oils are used in formulation without any considerations given to the peculiarities of their innate constituents particularly, vitamin, fatty acids and phytochemicals. Thus, the basis of these determinations. Three lipids: palm kernel oil (PKO), shea butter (SB) and sesame seed oil (SSO), were analyzed chemically in triplicate using standard methods. Results showed that SB had the highest (p<0.05) peroxide value (meq/kg) of 7.4 while PKO (0.7) and SSO (0.3) were similar (p>0.05). The iodine values (g/100g) of the lipids were not significantly different (p>0.05). The saponification value (mgKOH) of PKO (249.9) was significantly higher than SBO (190.9) and SSO (15.8) while the acid value (mgKOH/g) of SBO (10.6) was significantly lower (p<0.05). The α-tocopherol of SBO was 119.2 μg/mL which was significantly higher (p<0.05) than 69.6 μg/mL in SSO and 24.4μg/mL in PKO while there were significant variations (p<0.05) in the fatty acid composition of the oils. Analyses revealed the oils possessed variable chemical characteristics; while PKO would be most appropriate for soap production, SBO and SSO would be more susceptible to rancidity. Keywords: palm kernel oil, sesame seed oil, shea butter, pro-vitamin

The growth response of fingerlings of O. niloticus in sublethal test to paraquat

The initial mean wet weight of the test fish were 7.64:~c 1.3 for the control and 6.33~c 0.9, 6.88~c 0.9 and 6.2~c 0.7 for the fish exposed to 1.02, 1.40 and 2.0mg/l of paraquat in water respectively. Growth was estimated from the sum of the individual wet weights of the fish at 2, 4, 6 and 8 weeks of exposure to the toxicant and expressed as percent Cumulative wet weight gain. The results showed that the cumulative percent wet weight gain in the control group increased from 10.34% at 1 week to 36.13% at 8 weeks. The growth of fish that were exposed to 1.02, 1.04 and 2.00mg/l increased from 3%, 0.44% and 1.55% at 1 week to 30.81 %, 9.59% and 19.81 % at week 8 respectively. A statistically significant difference in growth rate of the treated and control was observed (p<0.05)

Analysis of Structure and Efficiency of Cassava Marketing in Ado-Ekiti Local Government Area of Ekiti State, Nigeria

The study examined the structure and marketing efficiency of cassava in Ado-Ekiti Local Government Area of Ekiti State, Nigeria. Primary data were obtained using structured questionnaires and multistage sampling method was employed to select 183 respondents comprising 93 farmers and 90 marketers. The Herfindahl-Hirschman Index and Gini Coefficient were used to measure the degree of market concentration and the nature of competition in the market. The Herfindahl-Hirschman indices were 0.323, 0.346, and 0.316 for farmers, wholesalers, and retailers, respectively, suggesting that the market was uncompetitive at all levels. The computed values of Gini coefficient for cassava farmers, wholesalers, and retailers were 0.532, 0.465, and 0.569, respectively, indicating uneven distribution of income and uncompetitive market conditions. Two channels of cassava marketing were identified and the study demonstrates that the farmer-wholesaler-retailer-consumer channel had higher marketing efficiency and thus provides marketers with better opportunities for making more profits. Based on the findings, it is recommended that micro credit facilities should be made accessible to market actors to encourage investment and improve efficiency in cassava marketing. Keywords: Cassava, marketing efficiency, Ekiti, Herfindahl-Hirschman Index, Gini Coefficien

Global, regional, and national age-sex-specific mortality and life expectancy, 1950–2017: a systematic analysis for the Global Burden of Disease Study 2017

BACKGROUND: Assessments of age-specific mortality and life expectancy have been done by the UN Population Division, Department of Economics and Social Affairs (UNPOP), the United States Census Bureau, WHO, and as part of previous iterations of the Global Burden of Diseases, Injuries, and Risk Factors Study (GBD). Previous iterations of the GBD used population estimates from UNPOP, which were not derived in a way that was internally consistent with the estimates of the numbers of deaths in the GBD. The present iteration of the GBD, GBD 2017, improves on previous assessments and provides timely estimates of the mortality experience of populations globally. METHODS: The GBD uses all available data to produce estimates of mortality rates between 1950 and 2017 for 23 age groups, both sexes, and 918 locations, including 195 countries and territories and subnational locations for 16 countries. Data used include vital registration systems, sample registration systems, household surveys (complete birth histories, summary birth histories, sibling histories), censuses (summary birth histories, household deaths), and Demographic Surveillance Sites. In total, this analysis used 8259 data sources. Estimates of the probability of death between birth and the age of 5 years and between ages 15 and 60 years are generated and then input into a model life table system to produce complete life tables for all locations and years. Fatal discontinuities and mortality due to HIV/AIDS are analysed separately and then incorporated into the estimation. We analyse the relationship between age-specific mortality and development status using the Socio-demographic Index, a composite measure based on fertility under the age of 25 years, education, and income. There are four main methodological improvements in GBD 2017 compared with GBD 2016: 622 additional data sources have been incorporated; new estimates of population, generated by the GBD study, are used; statistical methods used in different components of the analysis have been further standardised and improved; and the analysis has been extended backwards in time by two decades to start in 1950. FINDINGS: Globally, 18·7% (95% uncertainty interval 18·4–19·0) of deaths were registered in 1950 and that proportion has been steadily increasing since, with 58·8% (58·2–59·3) of all deaths being registered in 2015. At the global level, between 1950 and 2017, life expectancy increased from 48·1 years (46·5–49·6) to 70·5 years (70·1–70·8) for men and from 52·9 years (51·7–54·0) to 75·6 years (75·3–75·9) for women. Despite this overall progress, there remains substantial variation in life expectancy at birth in 2017, which ranges from 49·1 years (46·5–51·7) for men in the Central African Republic to 87·6 years (86·9–88·1) among women in Singapore. The greatest progress across age groups was for children younger than 5 years; under-5 mortality dropped from 216·0 deaths (196·3–238·1) per 1000 livebirths in 1950 to 38·9 deaths (35·6–42·83) per 1000 livebirths in 2017, with huge reductions across countries. Nevertheless, there were still 5·4 million (5·2–5·6) deaths among children younger than 5 years in the world in 2017. Progress has been less pronounced and more variable for adults, especially for adult males, who had stagnant or increasing mortality rates in several countries. The gap between male and female life expectancy between 1950 and 2017, while relatively stable at the global level, shows distinctive patterns across super-regions and has consistently been the largest in central Europe, eastern Europe, and central Asia, and smallest in south Asia. Performance was also variable across countries and time in observed mortality rates compared with those expected on the basis of development. INTERPRETATION: This analysis of age-sex-specific mortality shows that there are remarkably complex patterns in population mortality across countries. The findings of this study highlight global successes, such as the large decline in under-5 mortality, which reflects significant local, national, and global commitment and investment over several decades. However, they also bring attention to mortality patterns that are a cause for concern, particularly among adult men and, to a lesser extent, women, whose mortality rates have stagnated in many countries over the time period of this study, and in some cases are increasing

Mapping local patterns of childhood overweight and wasting in low- and middle-income countries between 2000 and 2017

A double burden of malnutrition occurs when individuals, household members or communities experience both undernutrition and overweight. Here, we show geospatial estimates of overweight and wasting prevalence among children under 5 years of age in 105 low- and middle-income countries (LMICs) from 2000 to 2017 and aggregate these to policy-relevant administrative units. Wasting decreased overall across LMICs between 2000 and 2017, from 8.4 (62.3 (55.1�70.8) million) to 6.4 (58.3 (47.6�70.7) million), but is predicted to remain above the World Health Organization�s Global Nutrition Target of <5 in over half of LMICs by 2025. Prevalence of overweight increased from 5.2 (30 (22.8�38.5) million) in 2000 to 6.0 (55.5 (44.8�67.9) million) children aged under 5 years in 2017. Areas most affected by double burden of malnutrition were located in Indonesia, Thailand, southeastern China, Botswana, Cameroon and central Nigeria. Our estimates provide a new perspective to researchers, policy makers and public health agencies in their efforts to address this global childhood syndemic. © 2020, The Author(s)

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