ghanaopendata/ghanaian-research-english huggingface dataset:
A Typology of Young Cocoa Farmers: Attitudes, Motivations and Aspirations

This paper presents a typology to highlight and describe the variation in attitudes among young farmers in rural Ghana, a group that has been treated in policy discourses and in development practice as largely homogenous. It further identifies motivations and aspirations associated with each type. A cluster analysis of survey data from 120 respondents yielded two types of young farmers: ‘positive’ and ‘resigned’. The likelihood of being in either category was found to be related to marital status, location, and whether one had a secondary occupation. Further, the ‘positive’ group were more likely to report being influenced by adult role models and more likely to aspire to stay in farming. Our findings underscore the relevance of socio-economic and ecological environment on young people’s attitudes to and decisions regarding farming and, consequently, on the outcome of policy and programmatic interventions meant to increase their participation in agriculture

Source: UG
U-pb ages and hf-o isotopes of zircons from late paleozoic mafic-ultramafic units in the southern central asian orogenic belt: Tectonic implications and evidence for an early-permian mantle plume

U-Pb age and Hf-O isotope data of zircons from the mafic-ultramafic complexes and their related rhyolites and granites in the Eastern Tianshan and Beishan regions were obtained by SIMS and LA-ICPMS. The Hf-O isotopic composition and Hf model age of the zircons are closely related to their tectonic setting and formation age. The zircons from the mafic-ultramafic complexes in the Bogeda-Haerlike and Jueluotage belts have higher εHf(t) (+8-+17) and lower δ18O (+4‰-+6‰), whereas most of the zircons in the gabbros, granites and rhyolite from the Middle Tianshan Massif and Beishan Rift display lower εHf(t) (0-+8) and higher ε18O (+5‰-+8‰). The positive εHf(t) and relatively lower δ18O values suggest that these mafic-ultramafic complexes were derived from depleted mantle which was subjected to subduction-related modification processes. The Hf isotopic composition of zircons in the granites has revealed that the growth of juvenile crust was also very significant in the southern margin of the Central Asian Orogenic Belt during the Paleozoic. The Hf model ages of the analyzed zircons, together with the regional geology suggest that the Beishan area had a northward subduction, possibly from ca. 900Ma to ca. 400Ma, whereas the Eastern Tianshan had a south-directed subduction most likely from ca. 600Ma to ca. 310Ma. Additionally, zircons with ca. 280Ma U-Pb ages display wider and more scattered εHf(t) and δ18O variations than the relatively older and younger ones, which further support the Early Permian mantle plume model. © 2010 International Association for Gondwana Research.

Source: UG
U-Pb geochronology of zircons from river sediments in Sri Lanka: Implications on early Archean to late Cambrian magmatism and episodic crustal growth

Geochronology of zircons from river-sediments in Sri Lanka has never been attempted. Here we present Rare Earth Elements (REE) and U-Pb isotopes of ∼700 zircon grains by laser ablation ICP-MS technique, from sediments of the major rivers in the Sri Lankan basement (rivers of Mahaweli, Kelani, Kalu, Walawe, Maduru Oya and Maha Oya). Most of the studied zircons display oscillatory zoning and Th/U > 0.1, confirming their igneous origin. U-Pb age distribution of these river-sand zircons exhibits two major populations depicting Mesoproterozoic to Archean (∼30%; >1100–3100 Ma) and Neoproterozoic to late Cambrian (∼70%; >430–1000 Ma) magmatism. The two populations could be further resolved into intensive and episodic magmatic peaks at 480–680 Ma, 680–1000 Ma, 1100–1300 Ma, 1300–1700 Ma, 1700–1900 Ma, 2100–2300 Ma, 2300–2600 Ma and 2600–3100 Ma. These river-sediment-zircon data are consistent with the principal episodes of global continental crustal growth and the recognized U-Pb ages of magmatism are mostly correlative with those obtained from basement rocks by previous studies of Sri Lanka. The older zircons found in this study may have mainly originated from reworked/recycled ancient (Palaoproterozoic to Archean) crust. A younger zircon group of 450–700 Ma with homogenous core-rim zoning texture and Th/U ratios <0.1 were inferred to be of metamorphic origin, indicating their possible crystallization at late Neoproterozoic metamorphic events, associated with the final assembly of the Gondwana Supercontinent. Thus, our data imply that the present-day continental crust of Sri Lanka may have predominantly formed and grown in the Neoproterozoic, while there is evidence that crustal growth began at least in the Paleoproterozoic. Further, the Mesoproterozoic peaks of the frequency distribution of U-Pb ages of river-sand zircons at ∼1.6 Ga and ∼1.1 Ga might reflect triggering of subduction in a paleo tectonic setting forming the Wanni and Vijayan dual arc systems, respectively.

Source: UG
U-Pb zircon age of deformed carbonatite and alkaline rocks in the Pan-African Dahomeyide suture zone, West Africa

It has been proposed that the association of deformed carbonatite and alkali rocks (DARC) can be used to map ancient suture zones. The hypothesis considers the intrusion of such alkali rocks as indicating an episode of lithospheric extension that preceded the suture-forming orogeny whereas the deformation evident in DARCs records the collisional event. As such, DARCs are predicted to provide samples that can date both the beginning and the late stages in a Wilson Cycle. The occurrence of carbonatite and nepheline syenite in the Pan-African Dahomeyide orogen of southeastern Ghana has been cited as an example of such rocks. To test this prediction, we have dated carbonatite and nepheline syenite from the Kpong complex that decorate the sole thrust of the suture zone in southeastern Ghana. ID-TIMS analyses of zircon from the carbonatite yield a U-Pb age of 592 ± 2 Ma and those from nepheline syenite an age of 594 ± 4 Ma. Titanite in the carbonatite defines an age range between 586 and 578 Ma. The identical zircon ages are distinctly younger than 612-605 Ma U-Pb zircon ages of the high-pressure mafic granulites inferred to date peak metamorphism and mark the suturing event, but older than 40Ar/39Ar hornblende age of 582 ± 2 Ma from the same unit interpreted as dating exhumation. Consideration of zircon characteristics and field relations suggest that the U-Pb zircon ages most likely define the time of magmatic crystallization of the Dahomeyide carbonatite and nepheline syenite, implying that they formed during syn-orogenic extension related to the collisional orogeny at the margin of the West African craton. Thus, DARCs may not always be useful in constraining the initiation of a Wilson Cycle heralded by lithospheric breakup. © 2007 Elsevier B.V. All rights reserved.

Source: UG
Ubiquitous Technologies and Learning: Exploring Perceived Academic Benefits of Social Media Among Undergraduate Students

This study makes an original contribution to the literature on social media usage for learning purposes through the phenomenological approach of enquiry. It examined the general motivations for social media usage, how social media is used to meet academic needs, perceived academic benefits, and how social media usage disrupts studies. A total of 24 undergraduate students were engaged in rigorous focus group discussions. Results showed that social media has been adapted to suit the academic needs of users through the process of appropriation. It was found that although social media could be a viable platform for inter-university collaborative learning, respondents hardly engaged in that. It was suggested that students create inter-university social media groups for collaborative learning. There were accounts of negative implications of using social media, like addiction and distractions. Students must adopt tactics to handle distractions which could prove helpful in out-of-school settings like the workplace.

Source: UG
UK-based real-time lymphoproliferative disorder diagnostic service to improve the management of patients in Ghana

The objective of the study was to evaluate the feasibility of a UK-based real-time service to improve the diagnosis and management of lymphoproliferative disorders (LPDs) in Ghana. Adult patients reporting to hospital with a suspected LPD, during a 1 year period, were prospectively enrolled. Bone marrow and/or lymph node biopsies were posted to the Haematology Malignancy Diagnostic Service (HMDS), Leeds, UK and underwent morphological analysis and immunophenotyping. Results were returned by e-mail. The initial diagnoses made in Ghana were compared with the final HMDS diagnoses to assess the contribution of the HMDS diagnosis to management decisions. The study was conducted at the two teaching hospitals in Ghana-Komfo Anokye, Kumasi and Korle Bu, Accra. Participants comprised 150 adult patients (>/=12 years old), 79 women, median age 46 years. Bone marrow and lymph node biopsy samples from all adults presenting with features suggestive of a LPD, at the two teaching hospitals in Ghana, over 1 year were posted to a UK LPD diagnostic centre, where immunophenotyping was performed by immunohistochemistry. Molecular analysis was performed where indicated. Diagnostic classifications were made according to international criteria. Final diagnosis was compared to the initial Ghanaian diagnosis to evaluate discrepancies; implications for alterations in treatment decisions were evaluated. Median time between taking samples and receiving e-mail results in Ghana was 15 days. Concordance between initial and final diagnoses was 32% (48 of 150). The HMDS diagnosis would have changed management in 31% (46 of 150) of patients. It is feasible to provide a UK-based service for LPD diagnosis in Africa using postal services and e-mail. This study confirmed findings from wealthy countries that a specialised haematopathology service can improve LPD diagnosis. This model of Ghana-UK collaboration provides a platform on which to build local capacity to operate an international quality diagnostic service for LPDs.

Source: UG
Ultra Performance Liquid Chromatography-Quadrupole Time-of-Flight Mass Spectrometry (UPLC-Q-TOF-MS)-based metabolomic analysis of mycelial biomass of three Ganoderma isolates from the Lower Volta River Basin of Ghana

The Department of Parasitology conducts research into parasitic diseases of public health importance with the overall goal of reducing their transmission and the heavy disease burden that they impose on affected populations. The Department maintains focus on parasitic diseases in general. These include major diseases such as malaria, and others listed under the Neglected Tropical Diseases (NTD) control initiative such as, lymphatic filariasis, onchocerciasis, schistosomiasis, soil-transmitted helminthiasis, trypanosomiasis and leishmaniasis.

Source: UG
Ultra-short laser pulse interaction with nickel films

Laser induced forward transfer method involves three sequence of events (i) laser pulse heats up the front surface of the film until it melts (ii) the melt front propagates through the film until it reaches the back surface and finally (iii) at or close to melt-through the metal vapour pressure at the front propels the molten film to the substrate. Many authors have shown potentials of this method in direct writing and photo-mask repair. In this paper, laser induced forward technique is applied to nickel films of thicknesses 98nm, 200nm and 322nm by using Ti: Sapphire femtosecond laser. Threshold energies for both direct and backside ablations are calculated. The feasibility of the transfer process is also demonstrated on nickel film on silicon wafer. Elevated features observed on some films during transfer process have been explained. © 2006-2011 Asian Research Publishing Network (ARPN).

Source: UG
Ultramafic–mafic and granitoids supra‐subduction magmatism in the southern Ashanti volcanic belt, Ghana: Evidence from geochemistry and Nd isotopes

Geochemical and Nd isotope data are presented for Palaeoproterozoic ultramafic to mafic rocks and granitoids which are associated with volcanic rocks in the southern part of the Ashanti greenstone belts of Ghana. The Prince's Town granitoids display subduction‐zone geochemical features, with some showing signatures similar to high‐SiO2 adakites (HSA). Their initial εNd (2.1 Ga) values range from −1.01 to +2.92, and they have TDM2 of 2.17–2.51 Ga. The gabbros show slightly LREE‐depleted and ‐enriched patterns, Th–U troughs, negative Nb, Zr–Hf and Ti anomalies, spikes in Sr and Pb, have εNd (2.1 Ga) values ranging from −1.23 to +5.23, and TDM2 values from 2.08 to 2.57 Ga. The Ahama ultramafic body is characterized by two groups of pyroxenites. Both groups show LREE enrichment patterns, display Th–U and Nb–Ta troughs, minor or pronounced negative Zr–Hf and Ti anomalies. However, the Group I pyroxenites exhibit minor Ce anomalies and lower total REE contents (28.1–32.8 ppm) whereas Group II pyroxenites show significant negative Ce anomalies and relatively higher total REE contents of 57.1–124 ppm. The pyroxenites show negative initial εNd (2.1 Ga) values (−0.58 to −5.68) and have TDM2 values of 2.52 to 2.75 Ga. The pyroxenitic and gabbroic rocks were most likely originated from a subduction‐related lithospheric mantle. The Aketakyi ultramafic–mafic complex is made up of mainly cumulate dunite, harzburgite, pyroxenites, and gabbro. The rocks display LREE‐depleted to flat patterns with low total REE contents (1.71 to 22.3 ppm) and demonstrate a supra‐subduction affinity. They show high positive initial εNd (2.1 Ga) values (+3.69 to +4.93), and TDM2 values of 1.99 to 2.04 Ga, which suggest that they were derived from depleted mantle magmas and were juvenile at their time of formation. The Nd isotopic data provides evidence for a possible contamination of the juvenile Birimian crust of the southern Ashanti belt by some amount of a pre‐Birimian (or Archaean?) crustal material. The trace element and isotopic signatures as well as the field relations of the studied granitoids and mafic–ultramafic rocks show they were derived through supra‐subduction‐related magmatism during the Palaeoproterozoic.

Source: UG
Ultrasensitive electrochemical genosensors for species-specific diagnosis of malaria

A B S T R A C T The absence of reliable species-specific diagnostic tools for malaria at point-of-care (POC) remains a major setback towards effective disease management. This is partly due to the limited sensitivity and specificity of the current malaria POC diagnostic kits especially in cases of low-density parasitaemia and mixed species infections. In this study, we describe the first label-free DNA-based genosensors based on electrochemical impedance spectroscopy (EIS) for species-specific detection of P. falciparum, P. malariae and P. ovale. The limits of detection (LOD) for the three species-specific genosensors were down in attomolar concentrations ranging from 18.7 aM to 43.6 aM, which is below the detection limits of previously reported malaria genosensors. More importantly, the diagnostic performance of the three genosensors were compared to quantitative real-time polymerase chain reaction (qPCR) assays using purified genomic DNA and the paired whole blood lysates from clinical samples. Remarkably, all the qPCR-positive purified genomic DNA samples were correctly identified by the genosensors indicating 100% sensitivity for each of the three malaria species. The specificities of the three genosensors ranged from 66.7% to 100.0% with a Therapeutic Turnaround Time (TTAT) within 30 min, which is comparable to the TTAT of current POC diagnostic tools for malaria. This work represents a significant step towards the development of accurate and rapid species-specific nucleic acid-based toolkits for the diagnosis of malaria at the POC.

Source: UG
Ultrasonic–biogenic synthesis of silver on anodized aluminum with superior antibacterial properties

The design and fabrication of high-touch surfaces with antibacterial properties can reduce microbial burden and subsequent nosocomial infections in a hygiene-critical environment. In the present study, biogenic silver nanoparticles (biogenic Ag-NPs) have been synthesized and deposited in situ on an anodized aluminum oxide surface using an ultrasound-assisted onion extract synthesis process. Morphological features and chemical composition have been characterized using scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDS), X-ray diffraction (XRD) spectroscopy, UV-Vis absorption spectroscopy and attenuated total reflection-Fourier transform infrared (ATR-FTIR) spectroscopy. The biogenic Ag-NP-coated anodized aluminum exhibited 100% E. coli bacteria inactivation under 60 minutes of contact

Source: UG
Ultrasound assisted enzymolysis of sunflower meal protein: Kinetics and thermodynamics modeling

This study examined the effect of dual‐frequency ultrasound (DFU) pretreatment on thermodynamics and kinetics of sunflower‐meal protein (SMP) using alcalase to improve efficiency in enzymolysis process. The concentration of hydrolyzed protein and kinetic parameters after traditional pretreatment (control) were investigated and compared with DFU‐assisted enzymolysis. The results indicated that DFU‐pretreatment enhanced SMP‐enzymolysis efficiency at different substrate and enzyme concentrations, temperature, and pH. Kinetics analysis showed DFU‐pretreatment reduced the Michaelis constant by 11.29%, while the apparent breakdown rate constant increased by 1.96%, indicating DFU‐pretreatment improved the affinity among substrate and enzyme. The rate constants for DFU‐pretreatment were increased by 45.96, 26.92, 21.14, and 27.89% at 293, 303, 313, and 323 K, respectively (p < .05). On Arrhenius kinetics, DFU reduced the activation energy, enthalpy and entropy by 24.28, 26.13, and 9.10%, respectively (p < .05). DFU had slight influence on Gibbs‐free energy when temperature increased from 293 to 323 K.

Source: UG
Ultrasound diagnosis of acrania with major low–lying placenta and polyhydramnios; case report

Acrania is a rare foetal anomaly in which the calvaria is absent, and the meninges come into direct contact with the amniotic fluid. Acrania is the most common anomaly in the acrania – exencephaly – anencephaly spectrum, with an incidence of 3.68 to 5.4 per 10,000 live births. We present a case of a primigravida who presented for an ultrasound on account of vaginal bleeding in early cyesis. Transabdominal ultrasound showed a viable foetus at 13 weeks without a calvaria, with the brain in direct contact with amniotic fluid. There was a low-lying placenta extending from the posterior to anterior part of the lower uterine segment, completely covering the internal cervical os (major low–lying placenta), a placental cyst and polyhydramnios (amniotic fluid index, AFI of 17 cm). A diagnosis of acrania with major low–lying placenta and polyhydramnios was made. Detailed ultrasound is required to detect acrania at 13 weeks. The diagnosis of acrania is required to help direct patient counselling and maternal expectation. When acrania and major low–lying placenta occur in the same patient, both diagnoses must be promptly made concurrently, regardless of gestational age and without waiting for placental trophotropism and migration to occur first.

Source: UG
Ultrasound Guided Hydrostatic Reduction of Intussusception in Children at Korle Bu Teaching Hospital: An Initial Experience

Intussusceptions is the telescoping or invagination of a portion of intestine (intussusceptum) into an adjacent segment (intussuscipiens). It is one of the common causes of bowel obstruction in infants and toddlers. Sonography has now been accepted as a method for guiding hydrostatic reduction of intussusception with tap water, normal saline or Ringer's lactate solution. This method is currently being used at Korle Bu Teaching Hospital. It is a very simple, efficient, economical and quick method of managing intussusception. The duration of the procedure ranges between two minutes and thirty minutes, with the majority being under ten minutes. A total of twenty intussusceptions were managed in eighteen patients over a nine month period. In fifteen patients (75%) the intussusception was reduced successfully. In five patients (25%), the procedure failed to reduce the intussusceptions.

Source: UG
Ultrasound pretreatment of sunflower protein: Impact on enzymolysis, ACE-inhibition activity, and structure characterization

Impacts of dual-frequency ultrasonic (DFU) with various operating modes (simultaneous and sequential modes) on degree of hydrolysis (DH) and conversion rate (CR) of sunflower meal protein (SMP) and activity of ACE-inhibition of SMP hydrolysates were examined. Results revealed that sequential and simultaneous modes enhanced DH by 7.73% and 11.22%, and CR by 26.23% and 26.98% of SMP (p < .05). Additionally, the maximal ACE-inhibition activity obtained at 75 min of enzymolysis was 64.46% for sonicated SMP hydrolysate (simultaneous mode), which was 32.52% higher than the control. Alterations in surface hydrophobicity, UV-Vis spectra, and intrinsic fluorescence indicated unfolding of SMP. AFM showed that sonication decreased the particles size and altered the structure of SMP. Amino acids composition demonstrated that both DFU modes pretreatments could improve the hydrophobic amino acids. Consequently, sonication enhanced DH, CR of SMP, and the activity of ACE-inhibition of hydrolysates confirmed by changes in SMP structure. Practical applications Sunflower protein, an extract from sunflower meal, is a potential source for preparing the bioactive compounds such as ACE- inhibition peptides. These peptides are safe, easy to absorb and stable, and have certain benefits for patients. Sonication with different operating frequency modes were applied to enhance enzymolysis of sunflower protein and ACE-inhibition activity of its hydrolysates. Sonication was displayed to be an operative technique to yield hydrolysates with good ACE-inhibition activity confirmed by monitoring the alterations in sunflower protein structure. Thus, sonication pretreatment of sunflower protein maybe practicable in the enzymolysis and the activity of ACE-inhibition in industry.

Source: UG
Ultrasound verification of bladder damage is associated with known biomarkers of bladder cancer in adults chronically infected with schistosoma haematobium in Ghana

Long-term infection with urinary schistosomiasis has been associated with development of bladder cancer. However, bladder cancer is difficult to diagnose without invasive measures such as cystoscopy, thus there is little information on the epidemiological extent of the problem. Studies have been either case-control studies or case examinations in different geographical areas, estimating a schistosome-associated bladder cancer incidence of 3-4 cases per 100,000. We have used three indicators to examine the potential bladder cancer problem in an adult rural population in Ghana endemic for urinary schistosomiasis: (i) parasitological positivity; (ii) age prevalence of bladder damage from ultrasound scans; and (iii) detection of biomarkers associated with the presence of bladder cancer. Biomarkers were BLCA-4 test (urine) and nuclear morphometry or quantitative nuclear grading (QNG) of epithelial cells (urine sediment), which quantifies DNA ploidy status and nuclear morphometric descriptors, both of which can detect the presence of bladder cancer. Our data show an increasing association between age, severe bladder abnormalities and the occurrence of these biomarkers. Sixty-two of 73 cytopathology Papanicolaou-stained smears were seen to have squamous metaplasia. Although further investigations are needed, we suggest that schistosome-associated bladder cancer is an important public health concern in areas where Schistosoma haematobium is prevalent.

Source: UG