The Free-Radical Copolymerization of Difurylmethane with Maleic Anhydride

The copolymerization of difurylmethane with maleic anhydride in the presence of azobisisobutyronitrile as an initiator has been investigated at 65 ºC, 72 ºC and 85 ºC in different solvents. Reaction feeds containing 85 mol % and higher of difurylmethane yielded a soluble alternating copolymer in which the furan residue entrained in the polymer chain formed 2,5 linkages and had 3,4 unsaturation. The 1:1 difurylmethane- maleic anhydride adduct was readily prepared, and at the above temperatures and in the presence of the radical initiator partially underwent retro-Diels-Alder reaction. Copolymerization of the difurylmethane and maleic anhydride thus formed yielded the unsaturated alternating copolymer. Copolymers prepared from reaction feeds with proportions of difurylmethane lower than 85 mol % had higher cross-link density and exhibited higher thermodecomposition temperatures. South African Journal of Chemistry Vol.55 2002: 1-1

Characterisation of selected volatile organic compounds in Rwandan indigenous beer ‘Urwagwa’ by dynamic headspace gas chromatography-mass spectrometry

The volatile organic compound profile of alcoholic beverages consists of a wide range of compounds, comprising of acids, alcohols, esters, aldehydes, and other trace level aroma compounds. These compounds play an important role as they provide relative information on the product quality and enhance product acceptability. In this study, two brands of commercially available traditional banana beer samples were collected from a local market in Kigali, Rwanda; and were analyzed for volatile organic compounds. Dynamic headspace, using gas chromatography-mass spectrometry (DHS/GCMS), was used to identify volatile compounds at three different temperatures. Fifty volatile compounds, inclusive of 14 acids, 14 alcohols, and 22 esters were identified and quantified in the two brands of indigenous banana beer samples. Only 12 volatile components (three alcohols, three acids and six esters) were common in all banana beer samples. Among all the identified compounds, ethanol and acetate were the dominant compounds in all beer samples. Ethanol levels were found to be 8.7 and 18.1% (v/v) for brand A and B, respectively using gas chromatography (GC). The two major toxic compounds, methyl alcohol and ethyl carbamate/urethane, were detected in lower concentration levels compared to other identified compounds, thus suggesting negligible risk.Keywords: Indigenous banana beer, volatile compounds, dynamic headspace, gas chromatography-mass spectrometry (GC-MS), ‘Urgwagwa’African Journal of Biotechnology Vol. 12(20), pp. 2990-299

Investigation of groundwater salinity using geophysical and geochemical approaches: Heuningnes catchment coastal aquifer. Western Cape Province, South Africa

Seawater intrusion is recognised as a major factor affecting the quality of groundwater in coastal aquifers around the world. To determine the occurrence and extent of saline groundwater intrusion prevailing in the Heuningnes Catchment, a 2D resistivity imaging survey was carried out in three sites within the catchment. Eleven resistivity profile lines were conducted using the multi-electrode ABEM SAS resistivity meter system, employing the Wenner Array to map the extent of saline groundwater. A 2D resistivity image was acquired for these resistivity profile lines and the data were processed using Res2DINV software to produce the 2D inverse resistivity models. The interpretation of the resistivity models revealed three resistivity zones. The first zone is characterised by low resistivity (1–3 Ω.m); this represents an aquifer filled with saline water. The second resistivity zone has values ranging from (3–30 Ω.m); this represents a brackish saturated formation. The third resistivity zone denotes a sandy layer/sandstone saturated with freshwater having high resistivity values above 30 Ω.m. Geochemical analysis results of water samples at 11 locations along the electrical resistivity profile lines also suggest high salinity, indicated by high levels of Cl−, Na+, Total Dissolved Solids, and Electrical Conductivity

Non-acid gastro-oesophageal reflux is associated with squamous cell carcinoma of the oesophagus

INTRODUCTION : Squamous cell carcinoma of the oesophagus is a common cancer among South Africans. Due to the absence of effective screening and surveillance programme for early detection and late presentation, squamous cell carcinoma of the oesophagus is usually diagnosed at an advanced stage or when metastasis has already occurred. The 5-year survival is often quoted at 5%–10%, which is poor. OBJECTIVES : To determine the association between oesophageal squamous cell carcinoma (OSCC) and non-acid gastro-oesophageal reflux disease. METHODS : A cross-sectional case–control analytical study of patients referred to the Gastroenterology Division of Steve Biko Academic Hospital in Pretoria, South Africa. All patients had combined multichannel impedance and pH studies done and interpreted after upper gastroscopy using the American College of Gastroenterology guidelines by two clinicians. RESULTS : Thirty-two patients with OSCC were recruited: non-acid reflux was found in 23 patients (73%), acid reflux in 2 patients (6%) and 7 patients (22%) had normal multichannel impedance and pH studies. Forty-nine patients matched by age, gender and race were recruited as a control group. Non-acid reflux was found in 11 patients (22%), acid reflux in 31 patients (63%) and 7 patients (14%) had normal multichannel impedance and pH monitoring study. CONCLUSION : The significance of the association between non-acid reflux and OSCC was tested using χ2, and simple logistic regression was used to adjust for the effects of potential confounders. The OR of developing OSCC in patients with non-acid gastro-oesophageal reflux was 8.8 (95% CI 3.2 to 24.5, P<0.0001) in this South African group. Alcohol and smoking had no effect on these results.http://bmjopengastro.bmj.comam2018Internal MedicineSurger

Training and development impact on job satisfaction, loyalty and retention among academics

Orientation: Extreme competition among institutions of higher learning was one of the difficulties that universities of technology (UoTs) had to overcome in order to enter the higher education system. This study examined the influence of training and development on job satisfaction, loyalty and retention among academic staff at a selected university of technology. Research purpose: The study investigated how training and development impact job satisfaction, loyalty and retention among academics. Motivation for the study: The competitive nature of the academic sector inspired universities to strive to attract and retain talented faculty members. Training and development programmes are considered potential tools to enhance job satisfaction, loyalty and retention, but empirical evidence is needed to support this relationship. Research approach/design and method: This study used a quantitative research methodology with a non-probability convenience sample (n = 270) of academics within the selected university utilising self-administered structured questionnaires to collect data. Main findings: The regression analysis revealed positive significant predictive relationships between training and development programmes and job satisfaction, loyalty and retention among academic staff. Practical/managerial implications: Findings imply that universities should prioritise the development of tailored training initiatives that address the specific needs and aspirations of their academic staff. Training interventions can foster a positive work environment and enhance staff members’ commitment and long-term engagement, ultimately improving the overall quality and reputation of the institution. Contribution/value-add: The study provided evidence-based insights to inform policies related to training and development programmes for both academics and institutions of higher education administrators

Effects of Egg's Weight on Egg Quality Traits of the Potchefstroom Koekoek Chicken Genotype

Egg is a reproduction tool for chickens and valuable food source for humans. The objective of this study was to examine the effect of egg weight (EW) on egg quality traits such as egg length (EL), egg diameter (ED), yolk weight (YW), albumen weight (AW), shell weight (SW), shell index (SI), yolk ratio (YR), albumen ratio (AR) and shell ratio (SR). Potchefstroom Koekoek layer genotype eggs (n = 200) were used. Pearson correlation and analysis of variance (ANOVA) were used for analysis. Correlation results indicated that egg weight had a statistical significant correlation (P &lt; 0.05) with egg quality traits. Egg weight displayed a positive significant correlation with EL (0.82), AW (0.67) and SW (0.62), respectively. The findings suggest that EL, AW and SW might be used to improve EW of Potchefstroom Koekoek chicken genotype. ANOVA results showed that egg weight had a statistical significant difference (P &lt; 0.05) with egg quality traits except albumen ratio and yolk ratio (P &gt; 0.05). Moreover, the findings revealed that small eggs weight had a longer egg length, yolk weight, shell weight, shell ratio and albumen weight than medium and large eggs. Large eggs had a higher egg diameter and shell index. Keywords: Albumen weight, egg length, large egg, medium egg, small egg, shell weigh

Profile of human papillomavirus genotypes in breast and oesophageal cancer patients in Pretoria, South Africa

BACKGROUND : The association between human papillomavirus (HPV) and cervical cancer is well established, and cervical cancer can be prevented through HPV vaccination. Little has been reported on the association between HPV and breast carcinoma (BC) or oesophageal squamous cell carcinoma (OSCC) in Africa. It is possible that use of appropriate HPV vaccines against genotypes responsible for these cancers may also prevent their development. OBJECTIVES : To investigate HPV genotype prevalence in BC and OSCC patients in Pretoria, South Africa (SA). METHODS : A retrospective cross-sectional study of BC and OSCC patients managed at Steve Biko Academic Hospital from 2015 to 2019 was undertaken. Patient medical records were analysed, and DNA was extracted from their archived pathology material and amplified by polymerase chain reaction before hybridisation for HPV genotypes. RESULTS : There were 101 patients with BC and 50 with OSCC. The prevalence of HPV infection in BC patients was 77.2%, with 35.6% highrisk (HR) genotypes, and that in OSCC patients 90.0%, with 56.0% HR genotypes. The most prevalent HPV genotypes (>20% each) were HPV 16, 70 and 51 for BC and HPV 51, 70, 16 and 82 for OSCC, with 31.7% and 60.0% of patients, respectively, having co-infection with ≥2 genotypes. CONCLUSION : The high prevalence of infection with multiple HPV genotypes in BC and OSCC patients, with HPV 16, 51, 70, 35 and 82 the most common genotypes in these cancers, warrants expansion of the current SA bivalent HPV 16/18 vaccine for girls to include boys, and inclusion of HPV 51, 70, 35 and 82, in order to prevent BC and OSCC as well as cervical cancer.Internal resources of the departments of Surgery and Anatomical Pathology.https://journals.co.za/journal/m.samjam2024Anatomical PathologyInternal MedicineSchool of Health Systems and Public Health (SHSPH)SurgerySDG-03:Good heatlh and well-bein

Dysphagia as a manifestation of esophageal tuberculosis: a report of two cases

<p>Abstract</p> <p>Introduction</p> <p>Esophageal involvement by <it>Mycobacterium tuberculosis </it>is rare and the diagnosis is frequently made by means of an esophageal biopsy during the evaluation of dysphagia. There are few cases reported in the literature.</p> <p>Case presentation</p> <p>We present two cases of esophageal tuberculosis in 85- and 65-year-old male Caucasian patients with initial complaints of dysphagia and epigastric pain. Upper gastrointestinal endoscopy resulted in the diagnosis of esophageal tuberculosis following the biopsy of lesions of irregular mucosa in one case and a sessile polyp in the other. Pulmonary tuberculosis was detected in one patient. In one patient esophageal stricture developed as a complication. Antituberculous therapy was curative in both patients.</p> <p>Conclusion</p> <p>Although rare, esophageal tuberculosis has to be kept in mind in the differential diagnosis of dysphagia. Pulmonary involvement has important implications for contact screening.</p

Osteoporosis, Rather Than Sarcopenia, Is the Predominant Musculoskeletal Disease in a Rural South African Community Where Human Immunodeficiency Virus Prevalence Is High: A Cross-Sectional Study.

The rollout of antiretroviral therapy globally has increased life expectancy across Southern Africa, where 20.6 million people now live with human immunodeficiency virus (HIV). We aimed to determine the prevalence of age-related osteoporosis and sarcopenia, and investigate the association between HIV, bone mineral density (BMD), muscle strength and lean mass, and gait speed. A cross-sectional community-based study of individuals aged 20-80 years in rural South Africa collected demographic and clinical data, including HIV status, grip strength, gait speed, body composition, and BMD. Sarcopenia was defined by the European Working Group on Sarcopenia in Older People 2 (EWGSOP2) guidelines, and osteoporosis as BMD T-score ≤ -2.5 (if age ≥50 years). The mean ± standard deviation (SD) age of 805 black South African participants was 44.6 ± 14.8 years, 547 (68.2%) were female; 34 (13.2%) were men, and 129 (23.6%) women had HIV, with 88% overall taking anti-retroviral therapy. A femoral neck T-score ≤ -2.5, seen in four of 95 (4.2%) men and 39 of 201 (19.4%) women age ≥50 years, was more common in women with than without HIV (13/35 [37.1%] versus 26/166 [15.7%]; p = 0.003). Although no participant had confirmed sarcopenia, probable sarcopenia affected more men than women (30/258 [11.6%] versus 24/547 [4.4%]; p = .001]. Although appendicular lean mass (ALM)/height2 index was lower in both men and women with HIV, there were no differences in grip strength, gait speed, or probable sarcopenia by HIV status. Older age, female sex, lower ALM/height2 index, slower gait speed, and HIV infection were all independently associated with lower femoral neck BMD. In conclusion, osteoporosis rather than sarcopenia is the common musculoskeletal disease of aging in rural South Africa; older women with HIV may experience greater bone losses than women without HIV. Findings raise concerns over future fracture risk in Southern Africa, where HIV clinics should consider routine bone health assessment, particularly in aging women. © 2021 The Authors. Journal of Bone and Mineral Research published by Wiley Periodicals LLC on behalf of American Society for Bone and Mineral Research (ASBMR)