Bird Species Diversity and abundance in the Abiriw Sacred Grove in the Eastern Region of Ghana

The sacred grove concept is one of the strategies developed by many human societies to conserve biological resources using a traditional approach. Sacred groves are currently under threat from anthropogenic activities due to lack of enforcement of traditional edicts to check encroachment. The birds inhabiting the Abiriw Sacred Grove in the Akwapim North District in the Eastern Region of Ghana were surveyed between February and April 2005 to determinethe current ecological status of the grove, and to establish a bird species list. The transect count method was used to sample the birds in the grove. A total of 411 individual birds belonging to 22 families and 66 species was recorded, out of which 211 individuals of 41 species occurred in the forest-cultivated land boundary, 111 (36 species) in pristine forest, and 89 (40 species) in secondary forest. A significant proportion of species in the grove were savanna specialists. Similarity indices indicated different levels of degradation of the various blocks. The current situation needs immediate attention to stem the tide of fragmentation and degradation

Effects of ascorbic acid, salt, lemon juice, and honey on drying kinetics and sensory characteristic of dried mango

The effects of ascorbic acid, salt solution, lemon juice, and honey pretreatment on the drying kinetics and sensory characteristics were studied. Pretreatments used affected the effective moisture diffusivity and rehydration properties of the dried mangoes. The effective moisture diffusivity values were 2.22 × 10-10 m2/s for ascorbic acid, 1.80 × 10-10 m2/s for salt solution, 2.01 × 10-10 m2/s for lemon juice, 1.93 × 10-10 m2/s for honey pretreated mangoes, and 2.31 × 10-10 m2/s for the control slices. Pretreatments enhanced the drying rate potential of mangoes. Among the thin-layer drying models fitted to the experimental data, the Middil model gave the best fit. The ascorbic acid pretreated samples were the best while the salt solution ones were the poorest with respect to reconstitution capacity. Consumer studies for overall preference for taste, colour, texture, flavour and chewiness of the dried products revealed that there was a higher preference for honey pretreated dried samples followed by the ascorbic acid, control, lemon juice, and salt solution pretreated samples. The results demonstrate that these pretreatments can be applied to enhance the moisture transport during drying and the quality of the dried products

Thermoelectric prospects of nanomaterials with spin-orbit surface bands

Nanostructured composites and nanowire arrays of traditional thermoelectrics like Bi, Bi(1-x)Sb(x) and Bi(2)Te(3) have metallic Rashba surface spin-orbit bands featuring high mobilities rivaling that of the bulk for which topological insulator behavior has been proposed. Nearly pure surface electronic transport has been observed at low temperatures in Bi nanowires with diameter around the critical diameter, 50 nm, for the semimetal-to semiconductor transition. The surface contributes strongly to the thermopower, actually dominating for temperatures T < 100 K in these nanowires. The surface thermopower was found to be -1 T microvolt/(K^2), a value that is consistent with theory. We show that surface electronic transport together with boundary phonon scattering leads to enhanced thermoelectric performance at low temperatures of Bi nanowire arrays. We compare with bulk n-BiSb alloys, optimized CsBi(4)Te(6) and optimized Bi(2)Te(3). Surface dominated electronic transport can be expected in nanomaterials of the other traditional thermoelectrics.Comment: 18 pages, 3 figure

Quasi-Automatic Monitoring System For Turning Operation Using Acoustic Emission Signal Response And Factorial Design Method

This work discusses the generation of a quasi monitoring system intended for an operator to change cutting tool during turning operation. The monitoring system uses the effects of turning va riables on acoustic emission signal responses and factorial experimental design approach. In cutting operations, acoustic emission provides useful information concerning the tool wear condition because of the fundamental differences between its source mechanisms in the rubbing friction on the wear land of the single point tool. In this study, effects of cutting speed, feed and tool condition on the acoustic emission signal are investigated using acoustic emission's energy, amplitude, and frequency response and 23 factorial design for turning operation. Cutting tests were performed using high-speed steel under dry conditions. Calculated effects, standard errors at 95% confidence level, and models governing the acoustic emission response to the cutting conditions have been generated from the acoustic emission signal responses. The generated models revealed that acoustic energy response is affected by significant interactions between cutting speed and feed, and insignificant interactions between cutting speed and tool condition, while the acoustic amplitude response is affected by insignificant interactions among cutting speed, feed, and tool condition. These results suggest that acoustic emission's energy and amplitude responses could be used to control the cutting speed and feed during turning operation, thus prolonging the life of the cutting tool.Journal of Science & Technology (Ghana) Vol. 27 (2) 2007: pp. 107-12

Smallholder shallow groundwater irrigation development in the upper east region of Ghana

In sub-Saharan Africa, there is paucity of information on the potential of groundwater resources. The limited available information paints a pessimistic view about groundwater resources. Due to its perceived inadequate availability, groundwater is associated with domestic use but the potential for using it for agriculture is not well reflected in the national irrigation policies. Contrary to official pessimism, farmers do use groundwater for agriculture in many countries of sub-Saharan Africa including Ghana. This paper analyzes the current extent of use, economics, socioeconomic impacts, and constraints and opportunities of shallow groundwater irrigation based on the experiences of smallholders in the three micro-watersheds of the White Volta Basin in the Upper East Region of Ghana

Missed Opportunities for the Diagnosis of Pulmonary Tuberculosis in Ashanti and Western Regions of Ghana; Polymerase Chain Reaction, A Better Tool

The diagnosis of Pulmonary Tuberculosis (PTB) has mainly relied on sputum microscopy and culture. The use of molecular techniques such as the Polymerase Chain Reaction (PCR) and its overwhelming advantages compared with conventional diagnostic methodologies cannot be overemphasized. The main aim of this work was to compare the diagnostic sensitivities of microscopy, culture and PCR. Suspected PTB sputum samples were prospectively collected from six hospitals in the Ashanti and Western regions of Ghana. Microscopy was carried out on all samples at the field sites. Apart from culture and PCR, repeat sputum microscopy was carried out in the laboratories of the Kumasi Centre for Collaborative Research (KCCR). Out of the total 425 cases recruited for the study, 123 (29.0%) were smear positive on site in contrast to 275 (64.7%) positivity rate at KCCR. Regarding culture, 254 (59.9%) samples were culture positive whilst PCR technique using INS 1&amp;2 and PR 8&amp;9 primers were positive in 59.9 % and 56% of cases respectively. The proportion of missed positive cases of microscopy were 131 (51%) compared with culture and 1.1% missed cases when compared with PCR. The sensitivity and specificity of microscopy were 123/254 (48.4%) and 154/302 (50.99%). The study confirms the superiority of PCR in the diagnosis of PTB and indicates that a substantial proportion of PTB cases are missed when microscopy alone is used. In areas where the incidence of PTB is high and at referral hospitals, PCR can be done to augment the diagnosis of TB.Keywords: Pulmonary Tuberculosis, Sputum Microscopy, Culture, Polymerase Chain Reactio

Lowered Serum Triglyceride Levels among Chronic Hepatitis B-Infected Patients in Ghana

Dyslipidemia is a common finding in most studies of liver diseases. Little is however known about the effect of the two pathological stages of chronic hepatitis B (CHB) infection – chronicsymptomatic and asymptomatic – on the distribution of serum lipids in CHB infection. We conducted a study on CHB-infected patients attending specialist care at the Gastro-Intestinal (GI) Clinic at the Komfo Anokye Teaching Hospital (KATH) during a 7-month period. 64 participants were randomly sampled over the period. On the basis of serological and liver enzyme assays, participants were categorised as chronic asymptomatic, chronic symptomatic and healthy individuals. The relationship between the hosts pathological stage of infection were evaluated with the indices of lipid metabolism – LDL, HDL, triglyceride, and total serum cholesterol using ANOVA. The 64 volunteers recruited in the study were found to consist of 18 patients (28.1%) who were chronic symptomatic, 35 patients (54.7%) who were chronic asymptomatic hepatitis B, and 11 (17.2%) were healthy subjects. Significant overall male dominance was observed among all categories of population enrolled (p=0.0063). Serum triglyceride levels decreased more among the CHB-infected population compared to the healthy individuals (p=0.0010) with value lowest among the chronic symptomatic population. Basal serum cholesterol, HDL, and LDL were unaffected by the disease. This work reveals that serum triglyceride is significantly lowered in CHB infection and that the extent of this decrease in host is independent of the pathological stage of the infection.Keywords: chronic hepatitis B, lipid metabolism, triglyceride, chronic symptomati

The modern pollen-vegetation relationship of a tropical forest-savannah mosaic landscape, Ghana, West Africa

Transitions between forest and savannah vegetation types in fossil pollen records are often poorly understood due to over-production by taxa such as Poaceae and a lack of modern pollen-vegetation studies. Here, modern pollen assemblages from within a forest-savannah transition in West Africa are presented and compared, their characteristic taxa discussed, and implications for the fossil record considered. Fifteen artificial pollen traps were deployed for 1 year, to collect pollen rain from three vegetation plots within the forest-savannah transition in Ghana. High percentages of Poaceae and Melastomataceae/Combretaceae were recorded in all three plots. Erythrophleum suaveolens characterised the forest plot, Manilkara obovata the transition plot and Terminalia the savannah plot. The results indicate that Poaceae pollen influx rates provide the best representation of the forest-savannah gradient, and that a Poaceae abundance of >40% should be considered as indicative of savannah-type vegetation in the fossil record