Geophysical Investigation of Some Flood Prone Areas in Ota, Southwestern Nigeria

Thirteen shallow vertical electrical resistivity soundings using Schlumberger array were conducted within the study area. The aim of the study was to investigate the nature of the subsurface in some flood prone areas within the study area by determining the lithology and the corresponding inverse model resistivities at the depths investigated and hence the cause of flooding in the area during the wet season. The resistivity sounding data were collected along seven traverses using a Campus Tigre terrameter. The observed data were interpreted quantitatively using curve matching and computer assisted iteration method. The results of the inversion show a lithology that comprises of the top soil and a paralic sequence of sand and lateritic clay at the depth investigated with varied resistivity and thickness. The flooding is thought to be due to the shallow lateritic clay layer at an average depth of 5.2 m with thickness ranging from 14.5m to 31.8m at the various points of investigation and the shallow depth of the water tabl

Prediction of the Optimal Reaction Temperature of the Riser of an Industrial Fluid Catalytic Cracking (FCC) Unit

A pseudo homogeneous two-dimensional (2D) model of an industrial Fluid Catalytic Cracking (FCC) riser is here presented. The FCC riser models of previous researchers were mostly based on the assumption of negligible mass transfer resistance and 1D plug flow. These assumptions undermine the accuracy of the models by over-predicting the optimum residence time of the riser. In this work the coke content of FCC catalyst was modeled as a function of the reactor temperature with the aim of predicting the operating conditions that will reduce coke on catalyst without undermining the yield of the key product (gasoline). Mass transfer resistance was incorporated in the reactor model to enhance the accuracy of the results. Catalyst deactivation was modeled based on the exponential decay function. The mass transfer coefficient and the catalyst effectiveness factor were estimated from empirical correlations obtained from literature. Data used for the simulation were sourced from an existing plant (KRPC) as well as from open literature. Finite difference numerical scheme was used to discretise the model governing equation. At the end of the investigation, three different operating temperature regimes were identified from the simulated results for the coking of FCC catalyst (low temperature, optimal temperature and high temperature regimes). An optimum operating temperature range of 786K-788K and an optimum catalyst-to-oil ratio (COR) range of 4.60-4.71 were predicted for the riser. Keywords: FCC; Finite difference, Mass transfer resistance, Catalyst deactivation, Riser models.

Effects of temperature in relation to sheet metal stamping

The demand to reduce the use of lubricants and increase tool life in sheet metal stamping has resulted in increased research on the sliding contact between the tool and the sheet materials. Unlubricated sliding wear tests for soft carbon steel sliding on D2 tool steel were performed using a pin-on-disk tribometer. The results revealed that temperature has an influencing role in the wear of tool steel and that material transfer between tool and sheet can be minimized at a certain temperature range in sheet metal stamping

Histopathological Alterations in the Liver and Kidney of the Fish Chrysichthys nigrodigitatus due to Heavy Metals in Niger River

Surveillance and monitoring of concentrations of heavy metals in water bodies may serve as an early alert system on bioaccumulation of heavy metals in aquatic food chain therein.  Histopathological examination of target tissues of the fish would reveal harmful effects of chemical pollutants like heavy metals in fish. This study determined the concentrations of heavy metals in water columns and in the fish Chrysichthys nigrodigitatus of Niger River at Onitsha as well as pathological alterations in liver and kidney tissues of the fish. Atomic Absorption Spectrophotometer was used in determination of concentrations (mg/l) of heavy metals namely, Zinc (Zn), Iron (Fe), Copper (Cu), Lead (Pb), Mercury (Hg), Cadmium (Cd), and Arsenic (As) in water and fish samples from the Niger River during the dry season of 2011 and proceeding wet season of 2012. Annual mean concentrations of Zn, Fe, Cu, Hg, Cd, and Arsenic in water columns were significantly lower (P<.05) than those in the fish. Annual mean concentrations of Zn, Cu, Cd, Hg, and Arsenic in fish however complied with WHO Standards in Aquatic Foods but Fe and Pb exceeded the WHO Standards. Extensive hyperaemia, oedematous sinusoids, hepatocytes in apoptosis with pyknotic nuclei, and wide spread necrotic hepatocytes with mononuclear leucocytes infiltrations and pigment deposits in liver tissues, as well as severe hyperaemia of the interstices with degenerating and necrotic tubular epithelial cells in kidney tissues were the major characteristic histopathological findings in the fish. Bioaccumulation of heavy metals in the fish indicated that Niger River at Onitsha was experiencing impairment, and that prolonged exposure of fish to heavy metals in the river may result in increased morbidity and mortality as well as reduced productivity in fish. Potential health risks associated with human consumption of heavy metal-contaminated fish and other aquatic food chain need not be over emphasized. Similar studies should be carried out in other Nigerian water bodies in order to increase the national information bank on chemical pollution which will help in the formulation of evidence-based policy decisions on methods of achieving sustainable environment. Keywords: Niger River, pollution, heavy metals, fish, bioaccumulation, liver and kidney, histopatholog

Impact of Agricultural Waste on Sustainable Environment and Health of Rural Women

The study worked on the impact of agricultural waste on sustainable environment and health of rural women.  Three specific objectives were formulated for the study and included to identify the constituents of agricultural waste, to determine the environmental and health impact of agricultural waste and to determine the effective management techniques of agricultural wastes. Three research questions and three null hypotheses were also formulated in line with the specific objectives. Survey research design was adopted for the study. Population for the study was 3970 representing 450 registered livestock farmers, 3270 rural women and 250 environmental health workers in Anambra State.  Proportionate random sampling technique was used to draw a sample of 350 respondents representing 40 registered livestock farmers, 286 rural women and 24 environmental health workers. Questionnaire developed by the researchers was used to collect data. The instrument was face validated by three experts and reliability was tested using cronbach alpha method which yielded a coefficient of 0.86. Data were collected with the help of fifteen research assistants and 325 instruments were retrieved representing 81% return rate. Mean and Standard Deviation were used to answer the research questions while ANOVA was used to test the null hypotheses at 0.05 level of significance and at the appropriate degrees of freedom. Any null hypothesis whose p-value was greater than 0.05 level of significance at the appropriate degrees of freedom was upheld while a null hypothesis was rejected when the p-value was less than 0.05 level of significance at the appropriate degrees of freedom. The findings of the study indicated that animal faeces, urine, used litter, beddings, animal carcass, dairy parlor washings, waste milk, wasted feed, feedlot run-off, paunch waste, abattoir waste water, animal viscera, horns, feather, bones, blood, fur, placenta, birth tissues, fetal membranes, aborted fetus among others are the materials that constitute agricultural waste. It was also found that that air pollution from burning of agricultural wastes, air pollution from cesspools, dioxins from burning agricultural wastes, dirty environment from heaps of agricultural wastes, stench/odour from decaying agricultural waste, defacing of the environment, eutrophication of water bodies, aquatic life destruction, spontaneous abortion, blue-baby syndrome, prolonged mensuration and early menopause, among others are the environmental and health impact of agricultural waste on rural women. It was recommended among others that Extension workers should properly educate farmers on the dangers of agricultural wastes and sensitize them on proper disposal methods. Keywords: agricultural waste, environment, health, rural women, pollution

Blood Flow Improvement Trial: Design and Enrollment Developing Topics

Background Midlife insulin resistance (IR) has previously been shown to be associated with lower cerebral blood flow (CBF), and is a potentially modifiable risk factor for dementia. The Blood Flow Improvement Trial (BFiT), NCT03117829 , tested a 12 week carbohydrate restricted diet (CRD) and exercise behavioral intervention to reverse IR, and aimed to 1) determine the extent to which improving or normalizing glucose homeostasis improves CBF and cognitive function in individuals with IR, 2) determine whether participants continue to maintain improved or normalized glycemic control for 6 months, and 3) determine changes in the human metabolome as individuals improve or normalize IR and glucose homeostasis through diet and exercise. Method Participants were recruited from the Wisconsin Alzheimer’s Disease Research Center and screened for metabolic risk factor eligibility based on the criteria shown in Table 1. The design involved a 12 week diet and exercise intervention focused on self‐monitoring to promote adherence. Exercise was conducted in a supervised group setting 3 days/week for 50 minutes and participants were instructed to exercise on their own an additional 2 days/week. Participants followed a CRD and monitored their own blood glucose with the goal of achieving and maintaining fasting blood glucose/dL. Participants underwent baseline, 12 week, and 6 month procedures including urine and blood labs/metabolomics, cognitive testing, fitness testing, and blood flow imaging via MRI (Table 2). Result The enrollment goal was 40 participants. 118 individuals were screened for eligibility, and 72.5% of the target enrollment was met; of those participants, nearly 80% completed the 12 week intervention. Of the 23 participants that completed the intervention, mean attendance was 70% for supervised exercise sessions and 81% for weekly behavioral coaching sessions. Figure 1 summarizes screening, enrollment, and procedure completion. Conclusion IR may be a modifiable risk factor for dementia. The BFiT pilot trial was designed to test the feasibility of exercise and CRD to reduce IR and improve brain blood flow in middle‐aged adults. Reasonable enrollment and completion N were achieved. Future analysis will center on barriers to enrollment and adherence, as well as analysis of the primary and secondary outcome measures

A Clinicopathological Review of Colonic Polyps in a Tertiary Hospital in North Central Nigeria

Background: Colorectal polyps, especially adenomas, are known as precursors of colorectal carcinomas. This study was aimed at determining the prevalence and histopathologic characteristics of colonic polyps among Nigerians that underwent colonoscopy at the University of Ilorin Teaching Hospital, Ilorin, Nigeria. The authors also determined the polyp detection rate and adenoma detection rate. Materials and Methods: This was a hospital-based cross-sectional study of all colonoscopy examinations performed at the University of Ilorin Teaching Hospital, Ilorin from March 2013 to September 2017. The endoscopy register was reviewed, and patients’ biodata, indications for colonoscopy and colonoscopic findings were recorded on a proforma. The histopathologic reports of the polyps were also retrieved and their diagnosis confirmed. Results: A total of 289 patients had colonoscopy carried out on them. The age of the patients ranged from 14 to 90 years with a mean ±SD of 57.0 ± 15.3 years and a median age of 58 years. There were 178 (61.6%) males and 111 (38.4%) females giving a M:F ratio of 1.6:1. The indications for colonoscopy were rectalbleeding 124 (42.9%); suspected colorectal cancer 67 (23.2%); abdominal pain 22 (7.6%); chronic diarrhea 18 (6.2%); surveillance colonoscopy 12 (4.2%); constipation 11 (3.8%); change in bowel habit 9 (3.1%); occult bleeding 6 (2.1%); others 20 (6.9%). Endoscopic findings were normal findings 89 (30.8%); hemorrhoids 88 (30.4%); colonic polyps 50 (17.3%); diverticulosis 34 (11.8%); rectal cancer 29 (10.0%); colon cancer 24 (8.3%); colitis 19 (6.6%); others 13 (4.5%). The findings were not mutually exclusive. The diagnostic yield was 69.2%. The overall polyp detection rate was 17.3%. Of the 50 patients with polyps, 33 (66.0%) were males (p = 0.481). Theadenoma detection rate was 4.8%. Conclusion: The authors conclude that their observed polyp detection rate is consistent with the estimated rates for Africa. Rectal bleeding and adenomatous polyps were the commonest presentation and histopathologic finding, respectively

Physical activity attitudes, intentions and behaviour among 18-25 year olds: a mixed method study

Peer reviewedPublisher PD