Exchange parameters from approximate self-interaction correction scheme

The approximate atomic self-interaction corrections (ASIC) method to density functional theory is put to the test by calculating the exchange interaction for a number of prototypical materials, critical to local exchange and correlation functionals. ASIC total energy calculations are mapped onto an Heisenberg pair-wise interaction and the exchange constants J are compared to those obtained with other methods. In general the ASIC scheme drastically improves the bandstructure, which for almost all the cases investigated resemble closely available photo-emission data. In contrast the results for the exchange parameters are less satisfactory. Although ASIC performs reasonably well for systems where the magnetism originates from half-filled bands, it suffers from similar problems than those of LDA for other situations. In particular the exchange constants are still overestimated. This reflects a subtle interplay between exchange and correlation energy, not captured by the ASIC.Comment: 10 page

The AgResults Nigeria Aflasafe TM Challenge Project: 2019 Annual Report

This report documents the key activities that were carried under the AgResults Aflasafe Pilot Project during the 2018/ 2019 maize-growing season on the verification process to trigger premium payments for successfully harvested and aggregated Aflasafe™-treated maize

AMINO ACID PROFILE AND POLYCYCLIC AROMATIC HYDROCARBONS (PAHS) OF SMOKED FARMED CLARIAS GARIEPINUS (BURCHELL, 1822) RAISED UNDER DIFFERENT CULTURE SYSTEMS IN IBADAN, NIGERIA

Fish food quality and safety is critical to consumers due to its public health implication. To exploit huge export opportunities for smoked farmed catfish, there is need for strict adherence to international quality and safety standards. This paper examined amino acid profile and polycyclic aromatic hydrocarbons (PAHs) of smoked farmed catfish Clarias gariepinus raised under different culture systems with a view to determining its quality and safety. Six farms with the two most common fish culture systems (3 concrete tanks (CTs) and 3 earthen ponds (EPs) were purposively selected based on frequency of harvest and yield. Fish samples (500±10g) obtained from these farms after 4 months of culture were processed, smoked, packaged and stored for 36 weeks. Amino acid profile in farmed fresh and smoked C. gariepinus was determined at 12, 24 and 36 weeks of storage and polycyclic aromatic hydrocarbons (PAH) was determined at 0 and 16 weeks of storage. These were compared with traditional smoked wild catfish obtained from local fish processor (LFP). The amino acids with highest concentrations (mg/g) found in this study were leucine (22.16 - 31.61 and 13.89 – 29.64), lysine (16.31 – 20.19 and 9.86 – 18.08), arginine (15.16 – 12.29 and 8.97 - 15.86), valine (15.96 – 21.35 and 9.68 - 19.36 ) and asparagine (19.66 – 21.61 and 12.36 mg/g – 20.71mg/g) for fresh and smoked catfish respectively. Levels of other amino acids ranged from 1.5mg/g to 9.98mg/g in smoked fish and 2.95mg/g to 12.21mg/g in fresh fish. The mean total poly aromatic hydrocarbons in smoked catfish at 16 weeks of storage were 0.039±0.004µg/kg, 0.034±0.005 µg/kg and 0.053±0.005 µg/kg for EP, CT and LFP, respectively. Therefore smoked farmed catfish raised under different culture systems still contain essential amino acids and Benzo(a)pyrene which is a carcinogen was not at detectable level in the samples

Chemical Composition, Microbial Content and Sensory Evaluation of Smoked Farmed Catfish Clarias gariepinus (Burchell, 1822) Raised Under Different Culture Systems in Ibadan, Nigeria

This paper examined chemical composition, microbial content and sensory evaluation of smoked farmed catfish Clarias gariepinus raised in different culture systems with a view to determining its quality and shelf life at ambient temperatures (28 ±2oC) and relative humidity (75% - 85%). Six farms with the two most common fish culture systems (3 concrete tanks (CTs) and 3 earthen pond (EPs) were selected based on frequency of harvest and yield. Fish samples (500±10g) obtained from these farms after 4 months of culture were processed, smoked, packaged and stored for 36 weeks. The values of moisture content, ether extract, crude protein, ash, crude fibre and nitrogen free extract obtained from smoked farmed C. gariepinus during storage ranged from 4.67% – 21.69%; 21.00% - 20.79%; 65.02% - 49.35%; 5.51% - 0.03%; 1.00% - 1.37% and 2.81% - 6.60%, respectively. Highest total viable count (TVC) in processed catfish from both systems (1.27x106±0.01cfu/g) were obtained in the 36th week of storage. Storage time has significant effects (p<0.05) on TVC. Smoked fish from local fish processor (LFP) had highest TVC >107cfu/g. Best sensory scores in processed catfish were 7.0±0.01; 6.5±0.01 and 5.0±0.03 at 24 week of storage for fish from EP, CT and LFP, respectively. All quality and safety indices were within International Commission of Microbiological Specification for Foods acceptable limits. Keywords: Total viable count, smoked fish, quality changes, protein content, textur

Rapid Assessment as an Evaluation Tool for Polio National Immunisation Days in Brong Ahafo Region, Ghana

Background: Despite reported high coverage of National Immunization Days (NIDs) campaign in many countries children are still being missed during these campaigns. This is a study of a rapid assessment done to determine OPV coverage during an immunization campaign. Methods: In this descriptive cross-sectional study, regional supervisors in Brong Ahafo region of Ghana visited randomly selected houses during the first round of the Polio NIDs in October 2004 to identify under-5 children that were reached with OPV vaccines in the households and those missed during the campaign. Results: In the 13 districts a 1607 houses visited by regional supervisors for rapid assessment, volunteers did not visit 4 (0.24%) houses. There were 3737 under five in all the houses visited by the supervisors for rapid assessment out which 42 (1.2%) were missed and unvaccinated and the reason was that the children were not at home. The assessment showed that the main sources of information to mothers / caretakers on NIDs were Gong-gong and radio. The assessment provided opportunities to identify proportion of children missed and ensure necessary intervention to reach them. Conclusion: Rapid assessment is a valuable tool for evaluation of NIDs; it enables timely intervention in covering missed children and helps in careful interpretation of the usual over 100% coverage often recorded during NIDs. It is recommended that this be practiced widely to improve quality of NIDs for early global eradication of poliomyelitis.Contexte : Malgr\ue9 la haute couverte rapport\ue9e lors des campagnes nationales d'immunisation, dans plusieurs pays des enfants sont toujours rat\ue9s par ces campagnes. Nous proposons une estimation rapide de la couverture durant une campagne d'immunisation. M\ue9thodes : Dans cette \ue9tude descriptive sur un \ue9chantillon repr\ue9sentatif, des maisons choisies au hasard ont \ue9t\ue9 visit\ue9 par les superviseurs r\ue9gionaux de la r\ue9gion de Brong Ahafo, Ghana lors du premier passage des journ\ue9es nationales d'immunisation contre la Polio en Octobre 2004. Il s'agissait d'identifier les enfants de moins de 5 ans ayant re\ue7u le vaccin dans ces maisons et d'identifier ceux qui n'ont pas \ue9t\ue9 vaccin\ue9s dans cette campagne. R\ue9sultats : Dans 13 districts, un total de 1607 maisons visit\ue9es par les superviseurs r\ue9gionaux, pour estimation rapide. Quatre maisons (0,24%) n'avaient pas \ue9t\ue9 visit\ue9es par les volontaires. Il y'avaient 3737 enfants de moins de 5 ans dans l'ensemble des maisons visit\ue9es par les superviseurs, parmi eux 42 (1,2%) n'avaient pas \ue9t\ue9 vaccin\ue9s et la raison \ue9taient que ces enfants \ue9taient absents de la maison. L'\ue9valuation avait montr\ue9 que les principales sources d'information des mamans/gardiens lors des journ\ue9es nationales d'immunisation \ue9taient les Gong-gong et la radio. L'estimation avait donn\ue9 des opportunit\ue9s pour la d\ue9termination de la proportion d'enfants non vaccin\ue9s et des interventions \ue0 faire afin d'atteindre ces enfants. Conclusion : L'estimation rapide est un instrument important pour l'\ue9valuation des journ\ue9es nationales d'immunisation, elle permet des interventions opportunes pour couvrir les enfants manqu\ue9s. Elle permet aussi de faire une interpr\ue9tation prudente du taux de couverture de 100% habituellement rapport\ue9 durant ces journ\ue9es nationales d'immunisation. Il est recommand\ue9 de vulgariser cette v\ue9rification afin d'am\ue9liorer la qualit\ue9 de ces journ\ue9es nationales d'immunisation pour une \ue9radication globale de la poliomy\ue9lite

Design, fabrication and evaluation of fish meal pelletizing machine

A 113.1kg/h fish meal pellet processing machine which produced 4mm diameter pellet, with an average length of 6mm was designed and fabricated. Design values of 210 was used for the maximum angle that the hopper wall formed with the vertical in the discharge zone, a critical stress of 1.3kPa of the ground particulate materials, and a density of 2.4521kg/m3 of the particulate materials, were used to obtain a hopper smallest outlet diameter of 12.7cm with a capacity of 24,118cm3 which proved efficient for the pelletizing machine. Two 3-cm diameter shafts carried the speed reduction gears with the perforated disc attached to the roller cutters on one end, while at the other end a 5hp motor was connected to the speed reduction gear by pulleys with diameters of 6cm and 12cm respectively. The speed reduction was 1:5 over a motor speed of 2000rpm. The fish meal pelletizing machine utilized 4kg of ingredients to produce 3.77kg pellets at an efficiency of 94.2%. The percentage loss due to unprocessed ground particulate materials was 5.8%.The moisture content of the fish meal pellets after 7days of drying in open air was 26.5% (wet basis). When tested for floatation, the pellets stayed afloat for 9 days, while the un-dried pellets only remained afloat for 2days. A combination of the weight of the twin roller cutters and the addition of some starch to the ground particulate materials assisted the compacting and gelatinization of pellet formed. This machine will be useful to medium and small scale aquaculture farmers and also reduce the need for foreign sources of fish meal in the aquaculture industry, thus conserving foreign exchange.Keywords: Ground particulate materials; mixing; compacting; gelatinizing; pelletizin

Implications of Indoor Air Pollution in Business Buildings in Nigeria

 Globally, the majority of individuals spend 90 percent of their daily routine time indoors. Outside air pollution adds to the toxins created in interior spaces owing to heating and cooling, which has a substantial impact on person healthiness (illness that results in mortality and morbidity) and productiveness. This study investigates the implications of air pollution on interior air quality in commercial buildings such as event centres in Kogi State, Nigeria. Descriptive research approach was used with a questionnaire administered to 120 participants chosen through a random sampling procedure in business buildings. Findings indicated that inadequate window and tiny door size, including absence of mechanical cooling devices linked favourably with higher temperature in the interior but negatively with its moistness. The results show that indoor air quality has negatively impacted on the workforce performance and productivity of the customers, and also on the efficiency of their activities in the event centres. Implication for practice is that designs of apertures should be large enough to allow for cross ventilation while mechanical cooling systems should be included in the design for optimal interior air quality. The study recommends synergistic interventions from academics, policymakers, and occupational practitioners to improve national standard and its implementation for the management and regulation of indoor air quality in inside settings in Nigeri

Occupational noise exposure and sensorineural hearing loss among workers of a steel rolling mill

Hearing loss is one of the most common chronic health conditions and has important implications for the patient’s quality of life. However, hearing loss is substantially underestimated and under treated. The purpose of this study was to determine the prevalence of sensorineural hearing loss among the workers in a steel rolling mill in Nigeria. Each of the 150 randomly selected subjects had a structured questionnaire administered to them, followed by a full otological examination. Of these, 116 had tympanometry and pure-tone audiometry. Also a noise mapping of their respective work units was done. The workers were exposed to noise levels varying from 49 to 93 dBA. About 28.2% of the 103 who had their audiogram analysed had mild to moderate sensorineural hearing loss in their better ear and 56.8% of them had mild to moderate sensorineural hearing loss in their worse ear. The pure-tone average and the average hearing thresholds at 4 kHz for the groups significantly increased with an increasing noise exposure level. The prevalence of sensorineural hearing loss among the study population is high; and noise exposure is at least contributory. Pre-employment and regular audiometry while on the job is highly recommended

Noise exposure, awareness, attitudes and use of hearing protection in a steel rolling mill in Nigeria

Objectives To study exposure to noise, the attitudes and knowledge towards noise-induced hearing loss and the actual use of hearing protection in a steel rolling mill in Nigeria. Methods A structured questionnaire was administered to 116 randomly selected workers to collect information relating to their knowledge and attitudes towards hazardous occupational noise and preventative measures. Noise mapping of the factory was also carried out. Results Time weighted average noise levels were: administrative area 49 dBA, mechanic/maintenance workshop 72 dBA, mill floor 86 dBA and finishing stage 93 dBA. There was high awareness of the hazard of noise to hearing (93%) and of methods of prevention (92%) but only 27% possessed hearing protectors and only 28% of these stated that they used them all the time. Conclusion While noise is recognized as a hazard, initiatives are required to increase use of effective preventative measures

Anthropometric Studies of Inner Canthal Distance, Outer Canthal Distance and Canthal Index of Adult Ibibios

Abstract: Outer canthal distance, Inner canthal distance and canthal index are important component of craniofacial anthropometry. Craniofacial anthropometry is vital in making a precise and systematic measurement of the human skull. Eight hundred (800) adults comprising 400 males and 400 females were used for this study. The subjects were measured for inner and outer canthal distances using a non-stretchable plastic ruler and the canthal index was obtained as the ratio of inner canthal distance and the outer canthal distance multiplying the resultant fraction by 100. The results showed that Ibibio males and females had inner canthal distances of 3.52 and 3.36 cm, respectively, outer canthal distances of 11.15cm for male Ibibios and 10.73 cm for the females. Mean canthal index for both males and females was 31.64 and 31.47, respectively. The canthal index of Ibibio males is higher than that of females (p<0.05) using Z-test. This study will be useful in anthropology and medicine most especially in craniofacial surgery