ghanaopendata/ghanaian-research-english huggingface dataset:
Characterization of frequency-chirped dynamic nuclear polarization in rotating solids

Most research activities involve the use of molecular methods such as regular PCR (PCR), quantitative PCR (Q-PCR), genomic sequence and analysis using different software, genetic engineering, probe hybridization techniques, biological and molecular cloning, evaluation of immune markers for laboratory diagnosis of infections, serological assays involving the use of rapid tests, ELISA-based evaluations and immunofluorescent assay techniques.

Source: UG
Characterization of functional disability among older adults in Ghana: A multi-level analysis of the study on global ageing and adult health (SAGE) Wave II

Background Functional disability is a common public health problem that affects the health and quality of life of older adults. This causes them to be highly dependent on other members of their fam ily, receive home care, or to be institutionalized. Although functional disability has been widely studied in developed country settings, very limited studies have focused on age related functional disability in sub-Saharan Africa, and in particular Ghana. The purpose of this study is to assess various factors associated with the difficulties in performing basic and instrumental activities of daily living among older adults in Ghana. Methods This cross-sectional study used data on 1610 older adults aged 50 years and above from the Study on Global Ageing and Adult Health (SAGE) survey Wave II conducted in Ghana. Nine standard functioning difficulty tools of WHODAS II was used for the analysis. The WHODAS II offers continuous summary scores with higher scores showing higher disability, and vice versa. A multi-level regression model was used to identify individual and household level risk factors linked to the functional disability of older adults. Results Female older adults (53.7%) reported having functional disability. The mean functional dis ability among older adults aged 50 years and above was 5.2 (± 5.9). Results indicated that older adults who are females, aged 70 years and above, and had three or more chronic con ditions had a higher functional disability. Also, older adults who have adequate fruit intake and belong to wealthier households were found to have a lower functional disability. Conclusions The study reveals that functional disability among older adults is frequent in Ghana and is associated with having three or more chronic conditions and being overweight/obese. Pre vention of functional disability in old age in Ghana is therefore a matter of great social and economic concern, which calls for coordinate efforts across the board to mitigate this public health challenge

Source: UG
Characterization of Healthy Housing in Africa: Method, Profiles, and Determinants

Housing is a key social determinant of health, with implications for both physical and mental health. The measurement of healthy housing and studies characterizing the same in sub-Saharan Africa (SSA) are uncommon. This study described a methodological approach employed in the assessment and characterization of healthy housing in SSA using the Demographic and Health Survey (DHS) data for 15 countries and explored healthy housing determinants using a multiple survey-weighted logistic regression analysis. For all countries, we demonstrated that the healthy housing index developed using factor analysis reasonably satisfied with both reliability and validity tests and can therefore be used to describe the distribution of healthy housing across different groups and in understanding the linkage with individual health outcomes. We infer from the results that unhealthy housing remains quite high in most SSA countries. Having a male head of household was associated with decreased odds of healthy housing in Burkina Faso (OR = 0.80, CI = 0.68–0.95), Cameroon (OR=0.65, CI=0.57, 0.76), Malawi (OR=0.70, CI=0.64–0.78), and Senegal (OR=0.62, CI=0.51– 0.74). Further, increasing household size was associated with reducing odds of healthy housing in Kenya (OR=0.53, CI=0.44–0.65), Namibia (OR=0.34, CI=0.24–0.48), Nigeria (OR=0.57, CI=0.46–0.71), and Uganda (OR=0.79, CI=0.67–0.94). Across In all countries, household wealth was a strong deterrent of healthy housing, with middle and rich households having higher odds of residing in healthy homes compared to poor households. Odds ratios ranged from 3.63 (CI = 2.96–4.44) for households in the middle wealth group in the DRC to 2812.2 (CI = 1634.8–4837.7) in Namibia’s wealthiest households. For other factors, the analysis also showed variation across countries. Our findings provide timely insights for the implementation of housing policies across SSA countries, drawing attention to aspects of housing that would promote occupant health and wellbeing. Beyond the contribution to the measurement of healthy housing in SSA, our paper highlights key policy and program issues that need further investigation in the search for pathways to addressing the healthy housing demand across most SSA countries. This has become critical amid the COVID-19 pandemic, where access to healthy housing is pivotal in its control.

Source: UG
Characterization of malaria transmission by vector populations for improved interventions during the dry season in the kpone-on-sea area of coastal Ghana

Background: Malaria is a major public health problem in Ghana. We present a site-specific entomological study of malaria vectors and transmission indices as part of an effort to develop a site for the testing of improved control strategies including possible vaccine trials. Methods. Pyrethrum spray catches (PSC), and indoor and outdoor human landing collections of adult female anopheline mosquitoes were carried out over a six-month period (November 2005 - April 2006) at Kpone-on-Sea, a fishing village in southern Ghana. These were morphologically identified to species level and sibling species of the Anopheles gambiae complex further characterized by the polymerase chain reaction (PCR). Enzyme-linked immunosorbent assay was used to detect Plasmodium falciparum mosquito infectivity and host blood meal sources. Parity rate was examined based on dilatation of ovarian tracheoles following dissection. Results: Of the 1233 Anopheles mosquitoes collected, An. gambiae s.l. was predominant (99.5%), followed by An. funestus (0.4%) and An. pharoensis (0.1%). All An. gambiae s.l. examined (480) were identified as An. gambiae s.s. with a majority of M molecular form (98.2%) and only 1.8%S form with no record of M/S hybrid. A significantly higher proportion of anophelines were observed outdoors relative to indoors (χ 2=159.34, df=1, p<0.0000). Only An. gambiae M molecular form contributed to transmission with a high degree of anthropophily, parity rate and an estimated entomological inoculation rate (EIR) of 62.1 infective bites/person/year. The Majority of the infective bites occurred outdoors after 09.00pm reaching peaks between 12.00-01.00am and 03.00-04.00am. Conclusion: Anopheles gambiae M molecular form is responsible for maintaining the status quo of malaria in the surveyed site during the study period. The findings provide a baseline for evidence-based planning and implementation of improved malaria interventions. The plasticity observed in biting patterns especially the combined outdoor and early biting behavior of the vector may undermine the success of insecticide-based strategies using insecticide treated nets (ITN) and indoor residual spray (IRS). As such, novel or improved vector interventions should be informed by the local malaria epidemiology data as it relates to vector behavior. © 2012 Tchouassi et al.; licensee BioMed Central Ltd.

Source: UG
Characterization of malaria transmission by vector populations for improved interventions during the dry season in the Kpone-on-Sea area of coastal Ghana

Abstract Background Malaria is a major public health problem in Ghana. We present a site-specific entomological study of malaria vectors and transmission indices as part of an effort to develop a site for the testing of improved control strategies including possible vaccine trials. Methods Pyrethrum spray catches (PSC), and indoor and outdoor human landing collections of adult female anopheline mosquitoes were carried out over a six-month period (November 2005 - April 2006) at Kpone-on-Sea, a fishing village in southern Ghana. These were morphologically identified to species level and sibling species of the Anopheles gambiae complex further characterized by the polymerase chain reaction (PCR). Enzyme-linked immunosorbent assay was used to detect Plasmodium falciparum mosquito infectivity and host blood meal sources. Parity rate was examined based on dilatation of ovarian tracheoles following dissection. Results Of the 1233 Anopheles mosquitoes collected, An. gambiae s.l. was predominant (99.5%), followed by An. funestus (0.4%) and An. pharoensis (0.1%). All An. gambiae s.l. examined (480) were identified as An. gambiae s.s. with a majority of M molecular form (98.2%) and only 1.8%&#8201;S form with no record of M/S hybrid. A significantly higher proportion of anophelines were observed outdoors relative to indoors (&#967; 2&#8201;=&#8201;159.34, df&#8201;=&#8201;1, p&#8201;&lt;&#8201;0.0000). Only An. gambiae M molecular form contributed to transmission with a high degree of anthropophily, parity rate and an estimated entomological inoculation rate (EIR) of 62.1 infective bites/person/year. The Majority of the infective bites occurred outdoors after 09.00&#8201;pm reaching peaks between 12.00-01.00&#8201;am and 03.00-04.00&#8201;am. Conclusion Anopheles gambiae M molecular form is responsible for maintaining the status quo of malaria in the surveyed site during the study period. The findings provide a baseline for evidence-based planning and implementation of improved malaria interventions. The plasticity observed in biting patterns especially the combined outdoor and early biting behavior of the vector may undermine the success of insecticide-based strategies using insecticide treated nets (ITN) and indoor residual spray (IRS). As such, novel or improved vector interventions should be informed by the local malaria epidemiology data as it relates to vector behavior.

Source: UG
Characterization of melting properties in dark chocolates from varying particle size distribution and composition using differential scanning calorimetry.

Melting properties in dark chocolates processed from varying particle size distribution (PSD), fat and lecithin content were studied using differential scanning calorimetry (DSC). Compositional parameters were PSD (D90 (90% finer than this size) of 18, 25, 35 and 50 μm), fat (25%, 30% and 35%) and lecithin (0.3% and 0.5%) contents. Variations in PSD had no influence on crystallinity of products. Fat and lecithin content influenced the degree of crystallinity and melting properties (Tend, Tindex and DHmelt) of the products. Increasing fat content caused consistent increases in degree of crystallinity and crystal size distribution, thus effecting significant changes in Tend, Tindex and DHmelt of their derived products. Increasing lecithin content however reduced the crystal sizes in products. Particle size (PS) increases had limited effects on Tonset, Tpeak, and DHmelt independent of fat and lecithin content. Significant decreases in Tend and Tindex were noted with PS increases at all fat and lecithin contents. Similar increases in Tend and Tindex were noted with increases in fat content at all PS and lecithin levels. Contrary, increasing lecithin content in products resulted in significant decreases in Tend, Tindex and DHmelt. Thus, variations in fat and lecithin contents during dark chocolate manufacture influence the crystallinity of products, and with PSD, they all influence the melting index (duration) of their derived products

Source: UG
Characterization of Mycosphaerellaceae species associated with citrus greasy spot in Panama and Spain

Greasy spot of citrus, caused by Zasmidium citri-griseum (= Mycosphaerella citri), is widely distributed in the Caribbean Basin, inducing leaf spots, premature defoliation, and yield loss. Greasy spot-like symptoms were frequently observed in humid citrus-growing regions in Panama as well as in semi-arid areas in Spain, but disease aetiology was unknown. Citrus-growing areas in Panama and Spain were surveyed and isolates of Mycosphaerellaceae were obtained from citrus greasy spot lesions. A selection of isolates from Panama (n = 22) and Spain (n = 16) was assembled based on their geographical origin, citrus species, and affected tissue. The isolates were characterized based on multi-locus DNA (ITS and EF-1α) sequence analyses, morphology, growth at different temperatures, and independent pathogenicity tests on the citrus species most affected in each country. Reference isolates and sequences were also included in the analysis. Isolates from Panama were identified as Z. citri-griseum complex, and others from Spain attributed to Amycosphaerella africana. Isolates of the Z. citri-griseum complex had a significantly higher optimal growth temperature (26.8°C) than those of A. africana (19.3°C), which corresponded well with their actual biogeographical range. The isolates of the Z. citri-griseum complex from Panama induced typical greasy spot symptoms in ‘Valencia’ sweet orange plants and the inoculated fungi were reisolated. No symptoms were observed in plants of the ‘Ortanique’ tangor inoculated with A. africana. These results demonstrate the presence of citrus greasy spot, caused by Z. citri-griseum complex, in Panama whereas A. africana was associated with greasy spot-like symptoms in Spain.

Source: UG
Characterization of Polycyclic Aromatic Hydrocarbons (PAHs) present in smoked fish from Ghana

The study was conducted to determine the levels of Polycyclic Aromatic Hydrocarbons (PAH) in smoked Scomba japonicus sampled from some Ghanaian markets. By way of preparation, smoked fish comes into contact with smoke or extremely high temperature which are potential sources of PAH generation. Levels of 20 individual PAHs including acenaphthene, acenaphtyelene, anthanthrene, anthracene, benz(a)anthracene, benzo(a)pyrene, benzo(b)fluoranthene, benzo(e)pyrene, benzo(ghi)perylene, benzo(j)fluoranthene, benzo(k)fluoranthene, chrysene, cyclopenta(cd)pyrene, dibenzo(ah)anthracene, fluoranthene, fluorene, indeno(1, 2, 3-cd)pyrene, naphthalene, phenanthrene and pyrene were determined in 34 smoked fish samples using gas chromatographic techniques with flame ionization detector. Benzo(a)pyrene, which is one of the very few PAHs for which a legal limit exists in different types of food matrices inaddition to other high molecular weight PAHs suspected to be carcinogens, were detected in most samples. © Maxwell Scientific Organization, 2011.

Source: UG
Characterization of Rock Samples from Yale Area of the Upper East Region of Ghana

Quantitative analysis of the mineral and elemental components of rock samples in Yale locality of Ghana, Africa has been done by using the Instrumental Neutron Activation Analysis (INAA) and Atomic Absorption Spectroscopy (AAS). Both the INAA and AAS tests independently showed that the samples were dominated by Mn. INAA showed that across all samples the average composition of Mn was 3322.90 +/-169.60 ppm. Ti (6625.299 +/- 344.68 ppm), Cr (291.27 +/-48.13 ppm) and Cu (16.50 +/- 1.43 ppm) were also revealed by the INAA test on the samples. The results from the AAS test confirmed that Mn was dominant, with an average composition of 6052.22 +/- 2219.03 ppm. The presence of Cr (67.32 +/-72.73 ppm) and Cu (91.61 +/- 69.53 ppm) was also confirmed in the samples from AAS tests. Additionally, Au (1.5 + /- 0.66 ppm) and Co (49.14 +/-15.18ppm) were found, but an AAS test could not be used to confirm the presence of these elements. Gold was detected and estimated for the first time in the rock sample in that area of Ghana. These preliminary results indicate that the Yale area in the Upper East region of Ghana has substantial amounts of Mn, Ti and gold, and signify that the area is a potential mining zone for Mn and Au. The results of the present study add to information on the minerology of the Yale area.

Source: UG
Characterization of soil-water retention with coarse fragments in the Densu Basin of Ghana

The presence of coarse fragments can have profound impact on soil moisture retention characteristics. The study was conducted to assess the effects of coarse fragments on the moisture retention characteristics of 16 soil series, developed over five different parent materials in the Densu basin. Soil profiles were excavated at five locations, to depths within 1.5 m in the field. Undisturbed soil core samples and disturbed samples were taken in triplicates from the major genetic horizons of each soil type within the effective root depth of 1 m. Coarse fragments content of soil more than 2 mm was measured on mass basis by sieving through a 2-mm mesh. Soil moisture retention was determined using the pressure plate apparatus at suctions of pF 1 (1.0 kPa), pF 2 (10.0 kPa), pF 2.5 (33.0 kPa) and pF 3 (100.0 kPa) for the undisturbed and pF 4.2 (1500 kPa) for the disturbed samples. The volumetric moisture content between field capacity (FC) pF 2.5 (33.0 kPa) and permanent wilting pointing (PWP) pF 4.2 (1500.0 kPa) was used to evaluate the available water content (AWC) by volume and then converted to root zone available water capacity (RZAWC) in millimetres (mm) assuming an effective root depth of 1 m within the basin. Results showed that soils formed over granite and its associations have high percentage of coarse fragments while soils developed over phyllites and its associations have high clay percentage. Soil organic matter was high in the topsoil of all profiles, ranging from 0.81 to 4.44% compared with the horizons below, and the bulk density of the topsoils were less than the limiting value of 1.6 Mg m-3. Site-specific moisture retention characteristics of the various soil series have been delineated. It was evident from the analyses that soils containing high clay content gave high RZAWC values compared with soils with high coarse fragments. Most of the topsoils of the profiles gave high RZAWC values compared with sub-layers with high amounts of coarse fragments. Critical water for plants establishment within the basin in the surface layer was quite favourable.

Source: UG
Characterization of T cell activation and regulation in children with asymptomatic Plasmodium falciparum infection

Background Asymptomatic Plasmodium infections are characterized by the absence of clinical disease and the ability to restrict parasite replication. Increasing levels of regulatory T cells (Tregs) in Plasmodium falciparum infections have been associated with the risk of developing clinical disease, suggesting that individuals with asymptomatic infections may have reduced Treg frequency. However, the relationship between Tregs, cellular activation and parasite control in asymptomatic malaria remains unclear. Methods In a cross-sectional study, the levels of Tregs and other T cell activation phenotypes were compared using flow cytometry in symptomatic, asymptomatic and uninfected children before and after stimulation with infected red blood cell lysates (iRBCs). In addition, the association between these T cell phenotypes and parasitaemia were investigated. Results In children with asymptomatic infections, levels of Tregs and activated T cells were comparable to those in healthy controls but significantly lower than those in symptomatic children. After iRBC stimulation, levels of Tregs remained lower for asymptomatic versus symptomatic children. In contrast, levels of activated T cells were higher for asymptomatic children. Strikingly, the pre-stimulation levels of two T cell activation phenotypes (CD8+CD69+ and CD8+CD25+CD69+) and the post-stimulation levels of two regulatory phenotypes (CD4+CD25+Foxp3+ and CD8+CD25+Foxp3+) were significantly positively correlated with and explained 68% of the individual variation in parasitaemia. A machine-learning model based on levels of these four phenotypes accurately distinguished between asymptomatic and symptomatic children (sensitivity = 86%, specificity = 94%), suggesting that these phenotypes govern the observed variation in disease status. Conclusion Compared to symptomatic P. falciparum infections, in children asymptomatic infections are characterized by lower levels of Tregs and activated T cells, which are associated with lower parasitaemia. The results indicate that T cell regulatory and activation phenotypes govern both parasitaemia and disease status in paediatric malaria in the studied sub-Saharan African population.

Source: UG
Characterization of the groundwater flow regime and hydrochemistry of groundwater from the Buem formation, Eastern Ghana

This study demonstrates the application of multivariate statistical methods in definition of groundwater recharge and discharge areas in a sedimentary basin in Ghana. Q-mode hierarchical cluster analysis (HCA) was applied to 57 hydrochemical data from the Buem formation in the northern part of the Volta Region in Ghana. R-mode HCA and R-mode factor analysis were then applied to the same dataset to reveal the processes controlling the hydrochemistry of groundwater from this hydrogeological formation. Results of both the Q- and R-mode analyses were backed by graphical methods. The analyses revealed two major water types, differentiated by salinity levels into four spatial groundwater associations. The characteristics of the four groundwater types are discussed. The recharge areas are characterized by Ca-HCO3 low salinity waters which evolve through rock-water interactions to Na-HCO3 high salinity waters in the discharge areas. This study finds that the hydrochemistry of groundwater from this formation is mainly controlled by the weathering of minerals, principally silicates in the aquifer matrix. The effects of the chemistry of recharging precipitation are higher in the recharge areas, while mineral weathering tends to be severe close to the discharge areas in the groundwater flow regime. All the four spatial groundwater associations have low sodium content, but salinity levels increase towards the discharge areas, such that some of wells in the discharge areas may not be acceptable for irrigation on grounds of high salinities which might affect the osmotic potentials of plants. © 2011 John Wiley &amp; Sons, Ltd.

Source: UG