Biosorption of Phosphate Ion on Albizia Lebbeck Seed Pod with and Without Organic Acid Modification

This study uses batch experiment to compare the binding efficiency of phosphate onto Albizia lebbeck (ALB) pod with and without citric acid (CALB) or tartaric acid (TALB) modification. The residual phosphate concentration was analyzed using ascorbic acid method and the generated data were fitted into equilibrium isotherms and kinetics models. Intra-particle diffusion model was used to describe the biosorption mechanism. Characterization by FTIR spectroscopy and SEM shows that modification was successful. The maximum biosorption capacity occurred at biosorbent dosage of 0.5 g for ALB and 1.0 g for CALB and TALB. At optimum pH for each biosorbents, phosphate biosorption capacity is in the order ALB>CALB>TALB. Equilibrium time of 90, 150 and 60 minutes were recorded for phosphate on ALB, CALB and TALB respectively. The biosorption capacity increases as the initial anion concentration increases with highest biosorption capacity of 5.296 mg/g for ALB. Langmuir isotherm describes CALB data while TALB data fits Freundlich. Results from this study suggest that unmodified Albizia lebbeck can be used as a low-cost, highly-efficient biosorbent for phosphate removal in effluents

Genetic variability and heritability studies of some reproductive traits in cowpea (Vigna unguiculate (L.) Walp.)

The success of most crop improvement programs largely depends upon the genetic variability and the heritability of desirable traits. The magnitude and type of genetic variability help the breeder to determine the selection criteria and breeding schemes to be used for improvement purposes. A screen house experiment was carried out at Samaru, Nigeria in 1999 and 2000 dry seasons to estimate the genotypic variability of some reproductive traits and their heritability in some selected cowpea varieties. Results of the study showed that there was considerable variation among cultivars for duration of reproductive phase and rate of photosynthate partitioning. Genotypic coefficients of variation were also high for days to first flower, 100-seed weight, plant height, and harvest index. Broad-sense heritability estimate (h2) was 98.9% for 100-seed weight, 94% for duration of reproductive phase, 84.5% for days to first flower, 83.9% for days to maturity, and 77.3% for harvest index. This information showed that there is sufficient genetic variance to warrant selection for improvement in the cowpea genotypes studied. We concluded that considerable progress in cowpea breeding could be achieved by exploiting these traits

Cervical screening with Luviva machine for early detection of cervical dysplasia: experience from Ekiti state, Nigeria

Background: Cervical cancer is a preventable and potentially curable cancer when detected early, yet it continues to be among the leading causes of cancer death in developing countries. Screening for cervical dysplasia is critical for early detection in order to reverse this trend. Several traditional screening methods such as pap smear test, HPV-DNA screening test, visual inspection with acetic acid or lugol iodine are in vogue with different specificity and sensitivity. LuViva advanced cervical scan is a new automated screening tool that has great promise for the detection of the disease in itsearliest form both in developing and developed countries.Objective: This study was designed to describe our experience with the use of LuViva advanced cervical scan as a primary screening tool for cervical dysplasia.Method: This is a descriptive cross-sectional study, whose data was obtained from the free health screening for civil servants in Ekiti State conducted between 11th and 21st February, 2014. Screening for Cervical dysplasia was conducted using the LuViva advanced cervical scan for women 40 years old and above. The result was automatically recorded and transferred to an Excel sheet for analysis.Result: A total sum of 254 patients was screened during the study period. Only one patient had a prior pap smear done. The automated self-reporting LuViva scan presented the result of the benign changes on the cervix as low risk in 143 patients (56.3%), moderate risk in 52 patients  15%) and high risk in 59 patients (11.5%). The machine further classified the dysplastic changes of the low, moderate and high risk categories as Atypical glandular cell (AGC), Atypical glandular cell favouring neoplasia (AGC-FN), Atypical g l a n d u l a r c e l l o f u n d e t e r m i n e d significance(AG-US), Atypical squamous cell of undetermined significance (ASC-US), Atypical squamous cell where high grade cannot be excluded (ASC-H) and Low grade squamous Intraepithelial lesion (LSIL). The proportion of moderate and high risk AGC (31.2%) was just slightly lower than the moderate and high risk of ASC-US (35.2%) while a higher percentage of43.9% in low grade squamous intraepithelial lesion was recorded among the patients.Conclusion: Our experience suggests that there is a place for the use of luViva scan in the primary screening for cervical dysplasia and there is a correlation between LuViva scan high risk result and histological diagnosis of cervical dysplasia.Keywords: Cervical screening, cervical dysplasia, civil servants, LuViva Scan, Ekiti State Nigeri

Ultrastructural and functional fate of recycled vesicles in hippocampal synapses

Efficient recycling of synaptic vesicles is thought to be critical for sustained information transfer at central terminals. However, the specific contribution that retrieved vesicles make to future transmission events remains unclear. Here we exploit fluorescence and time-stamped electron microscopy to track the functional and positional fate of vesicles endocytosed after readily releasable pool (RRP) stimulation in rat hippocampal synapses. We show that most vesicles are recovered near the active zone but subsequently take up random positions in the cluster, without preferential bias for future use. These vesicles non-selectively queue, advancing towards the release site with further stimulation in an actin-dependent manner. Nonetheless, the small subset of vesicles retrieved recently in the stimulus train persist nearer the active zone and exhibit more privileged use in the next RRP. Our findings reveal heterogeneity in vesicle fate based on nanoscale position and timing rules, providing new insights into the origins of future pool constitution

Reduced Expression of the Vesicular Acetylcholine Transporter and Neurotransmitter Content Affects Synaptic Vesicle Distribution and Shape in Mouse Neuromuscular Junction

In vertebrates, nerve muscle communication is mediated by the release of the neurotransmitter acetylcholine packed inside synaptic vesicles by a specific vesicular acetylcholine transporter (VAChT). Here we used a mouse model (VAChT KDHOM) with 70% reduction in the expression of VAChT to investigate the morphological and functional consequences of a decreased acetylcholine uptake and release in neuromuscular synapses. Upon hypertonic stimulation, VAChT KDHOM mice presented a reduction in the amplitude and frequency of miniature endplate potentials, FM 1-43 staining intensity, total number of synaptic vesicles and altered distribution of vesicles within the synaptic terminal. In contrast, under electrical stimulation or no stimulation, VAChT KDHOM neuromuscular junctions did not differ from WT on total number of vesicles but showed altered distribution. Additionally, motor nerve terminals in VAChT KDHOM exhibited small and flattened synaptic vesicles similar to that observed in WT mice treated with vesamicol that blocks acetylcholine uptake. Based on these results, we propose that decreased VAChT levels affect synaptic vesicle biogenesis and distribution whereas a lower ACh content affects vesicles shape

Response of Soybean Genotypes to Alecta vogelii Infestation under Natural Field Conditions

Field studies were conducted in 1995 and 1996 in the northern Guinea savanna of Nigeria to determine the response of 22 soybean genotypes to Alectra infestation. Significant differences were observed amongst soybean genotypes in number of Alectra shoots that emerged at 9 and 10 weeks after sowing and days to first Alectra emergence. Alectra emergence occurred later in early maturing soybean genotypes [54 days after sowing (DAS)] while with most late maturing genotypes, Alectra emergence started at 50 DAS. Result revealed that sixteen genotypes supported few or no Alectra shoots while six were susceptible. Soybean genotypes that supported high numbers of Alectra shoots recorded lower grain yields than those with fewer Alectra shoots. However, soybean genotypes, SAMSOY2 and TGX1485-1D that significantly supported high numbers of Alectra recorded grain yields similar to those of genotypes that supported few or no Alectra. These findings may be due to three possible mechanisms of resistance of soybean genotypes to Alectra parasitism. The sixteen genotypes, which supported few or no Alectra shoots, may have produced lower amounts of root exudates required for stimulation of germination of Alectra. They may also have prevented the initiation, attachment, and penetration of haustorium from Alectra plants to the roots of the hosts. These mechanism were however, not investigated in this study. Further studies may therefore be necessary to confirm our speculations. Soybean genotypes, SAMSOY2 and TGX1485-1D, which recorded high yield irrespective of high infestation with Alectra may exhibit tolerance to the parasite

Evaluation and Analysis of Frequency of Transformer Failures

The frequency of failed distribution transformers in Power Holding Company of Nigeria Plc, Akpakpava Business Unit network, Benin City, for a period of two years have been investigated in this work. The frequent power outages recorded in our communities resulting in customers dissatisfactions, economic losses, frustration, complains and demonstrations and wanton destruction of government properties call for concern and investigation. Transformers that dropped J&P fuses causing electric power supply interruption were tested to ascertain if the incipient or thorough fault that must have resulted in open-circuit or short-circuit fault current flowing through the device has damaged it so as not to reclose on fault which could be catastrophic. Logbooks containing complains at the different service units dispatch office were used for the study. The study revealed that in 2005, out of the 390 transformers in the network on load, 26 representing 6.67% failed, while in 2006 out of the 460 transformers in the network on load, 28 representing 6.10% failed the essential tests conducted and so they could not be energized to restore power to the customers connected to them. On opening the failed transformers to ascertain the level of damage, 53 representing 99.00% of the total 54transformers that failed in the period under review had burnt-coils, while the remaining 1 representing 1.00% had burnt tap changer. The work also revealed that 30 representing 56.00 % of the failed transformers were operating in the wear-out period of their useful-life, 10 representing 19.00% of the failed transformers had no name plate, while the remaining 14 representing 26.00% failed in their useful life period. Since the transformers failed the essential tests the insulating medium (i.e., oil) were not tested in all the cases to ascertain the degrading level of its dielectric strength. The investigation also showed that the failure rates fell within the failure rates accepted in developing nations in the world.Keywords: Practical Transformers, Frequency of Failure, Failed Transformer, Power Supply, Failure Rate, Stress, Losses, and Reliability

Heterosis and combining ability for grain yield and its components in induced sorghum mutants

No Abstract. African Crop Science Journal Vol. 13(2) 2005: 143-15

Performance, carcass characteristic and apparent nutrient digestibility of broiler chickens fed Palm-kernel extraction by-products

This study aimed at investigating the effect of by-products of palm kernel extraction; palm kernel extraction residue (PKER) and palm kernel sludge (PKS) based diets as replacement for maize in broiler diets. A total of 198 one-day old Marshal Broiler chickens were randomly assigned to six dietary treatments. Each dietary treatment had 33 birds with 11 birds per replicate. Maize in the diets was partly replaced by PKER and PKS each at three levels (0, 10 and 20%). The experiment was conducted in both starter and finisher phases. Growth responses, carcass evaluation and nutrient utilization were estimated. Data obtained were subjected to 2x3 factorial arrangement within the completely randomized design (CRD). Feed: Gain was influenced by the level of the palm kernel by-products during 1-28days of study. The weight gained during the 56 days period were not significantly higher (P>0.05) across the treatments All the carcass parameters measured were not significantly (P>0.05) affected by either PKER or PKS. However birds on PKER diets showed superior (P<0.05) nutrients use. In conclusion, the inclusion of palm kernel extraction by-products (between 10-20% PKER and 20% PKS) in the diets of broiler chickens is thereby encouraged for better growth and efficient feed utilization.Keywords: Nutritive evaluation, Palm kernel, By-products, Broiler Chicken