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Pyrolytic and provenance evaluation of organic matter from the tertiary niger delta basin, nigeria: implication on hydrocarbon generation.
Get PDFThe present work deals with evaluation of organic matter based on detailed Rock-Eval pyrolysis techniques studies to evaluate hydrocarbon generation potential of source rocks by collecting twenty- nine shale samples from well cuttings in the Tertiary Formations of the Niger Delta, Nigeria. The values of vitrinite reflectance (0.57–0.74%Ro) and maximum (Tmax: 420–445°C) confirmed that samples are at early maturity to matured stage enough to generate liquid and gaseous hydrocarbon. The cross-plot between hydrogen index (HI) and oxygen index (OI) atomic ratio indicates that samples were predominant in the bituminous rank and having kerogen Type III makes it suitable for hydrocarbon generation. Rock-Eval pyrolysis analysis (Types II-III and Type III kerogen) on shale samples from the Niger Delta reveals organic matter of predominantly terrestrial origin based on type III kerogen. The organic matter (OM) assemblages suggests a marine setting but dominated by terrestrial inputs likely related to fluvial processes which is function of most delta system. Based on high total organic carbon (TOC) value of 5.42wt% and Type III kerogen made the shale an excellent source rock, with gas-prone kerogen. The high OI, low total sulphur (TS) suggests terrestrially derived OM and deposition in an oxic and dysoxic shallow marine environment. In addition, HI and Tmax values describe the samples as a characteristic Type III dominant kerogen and potential to generate oil and gases while the Tmax, consistently indicate an immature to mature on the shale organic matter
Photocatalytic degradation of direct red 16 dye using Ag/Ag3VO4/AgVO3/GO nanocomposite
Get PDFIn this research, synthesized AgNPs/Ag3VO4/AgVO3/GO was applied as a visible-light sensitive photocatalyst for photocatalytic degradation of DirectRed 16 dye (DR16) fromaqueous solutions. The synthesized nanocomposite was analyzed by XRD, FESEM, TEM, EDX and Dot mapping. The effect of DR16 dye concentration, AgNPs/Ag3VO4/AgVO3/GO dosage, time and pH on photocatalytic removal of DR16 were studied.Results revealed that pH, dosage and DR16 concentration aremore important parameters than time on photocatalytic removal of the dye. The results indicate that 58.98% of DR16 removal was obtained under the following optimized conditions: DR16 concentration = 32mg L–1; Ag NPs/Ag3VO4/AgVO3/GO dosage = 0.2 g 50mL–1; pH = 4.5; 300W visible light for 155 min. So, it was concluded that the new nanocomposite can be used as an efficient visible-light photocatalyst for degradation of Direct Red 16 dye
C–H activation: A critical evaluation of a published method and its application towards inherently chiral calix[4]arenes
Get PDFC–Hactivation offers an intriguing access into inherently chiral calix[4]arenes, but has been little explored in the literature. In this article, we report our investigation into a published C–H activation method that uses carbamates to direct a palladium catalyzed C–Hactivation and subsequent reaction withN-bromosuccinimide. However,we show that this report is unfortunately flawed on a number of points. An earlier reported study revealed the more likely SEAr mechanism of the bromination reaction, which did not involve palladium catalysis. We nevertheless employed the SEAr bromination in an attempt to form inherently chiral calix[4]arenes, using a chiral (+)-menthyl carbamate as a directing group. Unfortunately, although the reaction was high yielding, the diastereomers formed were inseparable and we were unable to quantify their ratio. Subsequent removal of the chiral (+)-menthyl carbamate, returned a small positive optical rotation, suggesting that at least a level of asymmetric induction was achieved in the bromination to afford a non-racemic product
Exploring mixed gendered peer-to-peer conversations as a primary cancer prevention communication strategy among South African youth
No full textCancer prevention face-to-face conversations are rare, particularly when held between male and female youth. Tailored, audience-specific communication strategies targeting youth are necessary for primary cancer prevention to shape behaviour that could attenuate the spread of leading cancers. This article explores potential effectiveness of using mixed gender face-to-face conversations among university students as a primary prevention communication strategy that could lead to cancer prevention behaviour and promote early detection. Vignettes in qualitative research were constructed to provoke conversations about cancer prevention between a mixed gender group of 21 male and female South African university students. Findings show that the vignettes provoked conversations among participants about self-examination for cancer prevention as well as the types of tests required for common cancers such as breast cancer, prostate cancer and cervical cancer. The discussions revealed that there was a lack of knowledge about self-examination as part of primary cancer prevention. Conversations revealed an openness to discussing self-examination for early detection. Findings from this study provide insight into the potential of using peer-to-peer, face-to-face discussions between mixed genders as a primary prevention communication strategy by health promotion organisations in South Africa and other countries
The psychosocial support needed by nurses caring for patients diagnosed with Covid-19 infection in the North West Province, South Africa
No full textNurses caring for patients diagnosed with COVID-19 infection are exposed to many psychosocial challenges. Exploring and describing the psychosocial support needed for the nurses caring for patients diagnosed with COVID-19 is significant to determine what type of support is needed by the nurses. The objective of this study was to describe the psychosocial support needed by the nurses caring for patients diagnosed with COVID-19 infection in the North West Province of South Africa. A qualitative, descriptive phenomenological, contextual design was used to collect data. The study used a non-probability sampling approach and purposive sampling technique to select four focus group discussions (FGDs) from the four hospitalsselected for this study. Data were collected through semi-structured interviews and analysis was done using descriptive phenomenological data analysis to develop themes and categories. Measures to ensure trustworthiness were considered throughout the study. The finding indicated that it is difficult for nurses to care for COVID-19 patients because it is a novel disease. There is no specific treatment for COVID-19 and most patients who were diagnosed with COVID-19 were demised. Shortages of human and material resources to care for COVID-19 patients were also reported. Nurses caring for COVID-19 patients are at risk of being infected and they are physically and psychologically affected. The study shows that nurses caring for COVID-19 patients are physically, psychologically and socially affected by the disease. Therefore, they need the support of their managers through the appreciation of their work, provision of adequate Personal protective equipment (PPE) and human capital to provide quality patient care. Nurses caring for COVID-19 patients need psychological support when they are depressed. They also need colleagues from other wards to encourage them and not see them as the carriers of the disease. Also, the community needs to understand the risks that nurses caring for COVID-19 patients take and support them.  
A rare phenomenon: Experiences of abused men by partners in Vhembe District, Limpopo Province, South Africa
No full textIntimate Partner Violence or Domestic Violence is a world-wide phenomenon. Domestic abuse is a mixture of physical, sexual, verbal, and coercive behaviours designed to manipulate the other partner. Men abuse is a challenge in communities as men suffer in silence for fear of disclosure, stigmatization by family members, friends, community members and victimization by the service providers. The study aimed to explore experiences of men abuse by partners in Vhembe District, Limpopo Province, South Africa.A qualitative explorative descriptive and contextual research design was used. The population were abused men who were purposively sampled. Data was collected through face-to face interview using an audiotape. Data was analysed using thematic analysis. Trustworthiness and ethical considerations were adhered to throughout the study. Findings revealed two themes, experiences of multifactoral causes of abuse such as lack of financial resources, lack of intimacy, lack of decision-making in relationship and interference from family members and in-laws, as well as experiences of social and professional support. A balance of power in relationships should be advocated for both men and women. Men deserve protection from intimate partner abuse, and also have a right for better living as married men. The SDG no 5 reiterate gender equity for all. 
The effect of different mnemonic strategies and gender on ability to recall among secondary school students in Jos, Plateau State
No full textStudies have shown that males and females differ in memory associated with gender-stereotyped objects and that mnemonic strategy differs in the ability to recall information. However, specific findings have been inconclusive regarding the specifics of these differences. This study therefore, experimentally investigated mnemonic strategies on student’s ability to recall, adopting an independent group-randomised design. Quantitatively, the effect of mnemonic strategies on recall ability through the ecological validity of self-paced word repetitions, mental imagery and sentence-by-sentence presentations by comparison to normal page reading with respect to comprehension and recall across three groups (A, B and C) were investigated among senior secondary school students in Jos, Plateau state. The results showed that mnemonic strategies do not differ in recall ability (F2, 207 = 0.61, p=.55). Female students recalled more and performed better on mental image mnemonic than male students (t (68) = 3.23, p = .002). Female students recalled more and performed better on sentence mnemonic than male students (t (68) = 2.04, p = .045) and no significant difference was found between male and female students in the recall task on word repetition mnemonic (t (68) = 1.48, p = .145). It was concluded that the ability to recall is influenced by an interaction between stimulus and participant gender. Implications and directions for future research are discussed. 
Board gender diversity and financial performance of listed deposit money banks in Nigeria
No full textThe study explored the relationship between the board gender diversity and financial performance of the selected deposit money banks in Nigeria. The research design used was ex-post-facto research design with a population of 24 listed deposit money banks in Nigeria as documented by the central bank of Nigeria. The Purposive and quota sampling techniques were used to select the sampling size of five (5) deposit money banks in Nigeria. These five (5) deposit money banks in Nigeria were selected based on the availability of their annual financial statements. The data were obtained from the audited annual financial statements of the selected deposit money banks in Nigeria between 2017 – 2021. The method of data analysis used were descriptive and correlation statistics to test the research hypotheses. The study revealed that the efficiency of female board members was positive and significantly related with the financial performance of deposit money banks in Nigeria. Also, the female CEO and Board gender diversity were negative but significantly weak related with the financial performance of deposit money banks in Nigeria. Based on these findings, the study therefore concluded that the efficiency of female board, female CEOs and board gender diversity were related to the financial performance of deposit money banks in Nigeria. Meanwhile, there is a negative and significant association between board gender diversity and the financial performance of deposit money banks in Nigeria. The study therefore recommended that the female managers and other key players shall incorporate board gender policies and regulations to enhance the financial performance of deposit money banks in Nigeria. Also, deposit money banks in Nigeria should appoint board members based on their skills, competencies, experiences and level of education attained. 
Production of gluconic acid from sweet potato peels using naturally occurring fungi by submerged fermentation
Get PDFThe oxidation of glucose produces gluconic acid, a significant organic acid. The aim of this study was to produce gluconic acid from sweet potato peels by submerged fermentation. Isolation and identification of fungi were done using standard microbiological methods. Proximate analysis of substrate and screening of fungal isolates for gluconic acid production was done using standard procedures. Gluconic acid yields were determined using High Performance Liquid Chromatography. A standard gluconic acid producer, Aspergillus niger ATCC 10577, was used as control. A sum of six different fungal species were isolated and identified. They included Aspergillus niger, Aspergillus flavus, Penicillum sp., Cladosporium sp., Rhizopus stolonifer and Aspergillus terreus. Proximate composition of the sweet potato peels showed percentage carbohydrate of 20.81 ± 0.07, percentage moisture of 64.02 ± 0.27. Screening for gluconic acid production showed that Aspergillus niger had the highest zone of clearance and identified as Aspergillus niger UFMGCB 14248. Our data further showed that gluconic acid concentrations (mg/ml) was highest at substrate concentration 50 g/L, carbon source starch, incubation day 7 and pH 6 for both Aspergillus niger UFMGCB 14248 and Aspergillus niger ATCC 10577. The findings showed that the fungal isolates used in this study were good gluconic acid producer
Evaluation of entrance surface dose and justification of pediatrics chest radiography in three university-affiliated hospitals at Yaounde - Cameroon: Évaluation de la dose d’entrée de surface et de la justification des radiographies thoraciques de l’enfant dans trois hôpitaux universitaires de Yaoundé - Cameroun
No full textObjective : Evaluate the patient radiation doses and the justification of chest radiography in children, in Yaoundé – Cameroon.Methods : A cross-sectional study was carried out on 118 children aged from 0 to 15 years in the Radiology units of Yaoundé gyneco-obstetrical and pediatric Hospital, University Hospital Center, and the Medical Centre of CNPS within 5 months (January – Mai 2016). The justification of the chest radiographies was evaluated from the pertinence of the clinical indications. The clinical information were categorized and compared to the recommendations of the Radiology Good practice guide. The Entrance Surface Dose (ESD) was calculated using the Davies formula (ESAK) = O/P × (kV/80)2 × (100/DFP) 2× mAs × BSF ; where the X-Ray tube output (OP) of the radiology equipment was calculated for a voltage of 80 KV and a charge of 20 mAs, with a source to skin distance of 1 metre. The other data collected and analyzed where the qualification of the prescriber, the age, height and Body mass index of the patients.Results : 21 radiographies where excluded due to poor image quality. The three X-ray machines included in the study were analog radiography, Digital Radiography and Computed Radiography. In our study, 58% of patients were male. The largest age group was children aged 2 to 12 months (38, 1%). The mean age was 39.08 months (± 47.6). The radiography was justified in 82.5% of cases regardless of the qualification of the prescriber. In 74% of cases, the ballots showed no research question. There was no significant correlation between the prescriber and the justification of the radiography. The X-ray tube voltage varied between 50 and 121 kV, while the average charge was 2.78 mAs (± 1.4). The source to skin distance ranged between 104 and 189 centimeters, with an average of 146 cm (± 15). We observed a high variability of the voltage used in infants, between 80 and 100 kV. The lowest charge values (1.3 ± 0.3 mAs) were used in CHE / CNPS, highest values (6.5 ± 3.5) were delivered to new-born in HCY. The values of the entrance surface doses generally ranged from 21.1 to 304.1 μGy with an average of 117.3 (± 53.1) μGy.Only the analog radiography equipment of HCY had X-ray filters of at least 2.5 mm Al corresponding to the minimum recommendations of the RP 162 of the European Commission. However, the X-Ray tube output of the HCY’s radiography device calculated (18.09 μGy / mAs) was Inferior to the normal according to IAAE. The values of ESD in HGOPY and CHE / CNPS were higher than those recommended by the NRPB and the European Commission. The value of ESD generally increased with age. The study highlighted the fact that the ESD value decreased as the source to skin increased. Meanwhile, the ESD value increased as the voltage and charge increased (r = 0.407; p <0.001).Conclusion: This study was an approach to the evaluation of exposure levels for chest radiography in children in Yaounde. A significant proportion of examinations was unjustified (17.5%). The average recorded doses were significantly higher than those recommended in international DRLs for most age groups; this is certainly linked to the failure to implement international recommendations regarding radiographic technics and the equipment.
Objectif : Evaluer la dose-patient et la justification des indications de la radiographie du thoracique de face de l’enfant à Yaoundé.Matériels et méthode : Etude transversale portant sur 118 enfants âgés de 0 à 15 ans, reçus dans les services de Radiologie de l’Hôpital Gynéco-Obstétrique et Pédiatrique de Yaoundé (HGOPY), l’Hôpital Central de Yaoundé (HCY) et du Centre Hospitalier de la CNPS (CHE/CNPS), en 5 mois (Janvier à Mai 2016). La justification des radiographies réalisées était appréciée à partir de la pertinence de l’indication clinique. Les renseignements cliniques étaient catégorisés, puis confrontés à la mention d’indication et aux grades de recommandation du Guide de Bon Usage de la SFR. La Dose d’Entrée de Surface (DES) a été calculée par la formule de Davies : (ESAK) = O/P × (kV/80)2 × (100/DFP) 2× mAs × BSF ; où le rendement des appareils (O/P) a été calculé pour une tension de 80kV pour 20 mAs à 1 mètre du foyer. Les autres données recueillies et analysées étaient l’âge, la taille, l’IMC des patients et la qualification du demandeur.Résultats : 21 radiographies ont été exclues pour mauvaise qualité de l’image. Les 3 appareils de radiographie inclus dans l’étude étaient de types analogique, Digital Radiography (DR) et Computed Radiography (CR). 58% des patients étaient de sexe masculin. Le groupe d’âge le plus représenté était celui des enfants de 2 à 12 mois (38,1%). L’âge moyen était de 39,08 mois (± 47,6). L’examen était indiqué dans 82,5% des cas quel que soit la qualification du prescripteur. Dans 74% des cas, les bulletins ne présentaient aucune question de recherche. Il n’y avait pas de corrélation significative entre le prescripteur et la justification de l’examen. La tension du tube radiogène variait entre 50 et 121 kV, tandis que la charge moyenne était de 2,78 mAs (± 1,4). La distance Foyer Peau variait entre 104 et 189 centimètres, pour une moyenne de 146 cm (±15). On observait une grande variabilité de la tension utilisée chez les nouveau-nés, entre 80 et 100 kV. Les valeurs de charge les plus faibles (1,3±0,3 mAs) étaient utilisées au CHE/CNPS, les plus élevées (6,5±3,5) étaient octroyées aux nouveau-nés à l’HCY. Les valeurs des doses d’exposition à la surface variaient globalement de 21,1 à 304,1 μGy avec une moyenne de 117,3 (±53,1) μGy.Seul l’appareil de radiographie de l’HCY possédait une filtration du tube d’au moins 2,5 mm Al correspondant aux recommandations minimales du RP 162 de la commission européenne. Toutefois, à l’HCY le rendement de l’appareil calculé (18,09 μGy/mAs) était inférieur à la normale selon le RP 162 de la commission européenne. Les valeurs des DES à l’HGOPY et au CHE/CNPS étaient supérieures à celles recommandées par la National Radiological Protection Board (NRPB) et la commission européenne. L’étude a permis de mettre en évidence une influence négative de la Distance foyer-peau sur la valeur de la DES, ainsi qu’une influence positive de la tension et de la charge (r = 0,407 ; p < 0,001) utilisée sur la valeur de DES.Conclusion : Cette étude a constitué une approche de l’évaluation dosimétrique des niveaux d’exposition pour la procédure diagnostique qu’est la radiographie du thorax chez l’enfant à Yaoundé. Une proportion importante d’examens était non indiquée (17,5%). Les moyennes des doses relevées étaient largement plus élevées que celles recommandées dans les NRDs internationaux pour la plupart des groupes d’âges, ceci étant lié assurément au défaut d’application des recommandations internationales, en ce qui concerne la techniqueradiographique, ainsi que l’équipement