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    WSV2023-The second meeting of the world society for virology : One health - One world - One virology

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    The Second International Conference of the World Society for Virology (WSV), hosted by Riga Stradiņš University, was held in Riga, Latvia, on June 15–17th, 2023. It prominently highlighted the recent advancements in different disciplines of virology. The conference had fourteen keynote speakers covering diverse topics, including emerging virus pseudotypes, Zika virus vaccine development, herpesvirus capsid mobility, parvovirus invasion strategies, influenza in animals and birds, West Nile virus and Marburg virus ecology, as well as the latest update in animal vaccines. Discussions further explored SARS-CoV-2 RNA replicons as vaccine candidates, SARS-CoV-2 in humans and animals, and the significance of plant viruses in the ‘One Health' paradigm. The presence of the presidents from three virology societies, namely the American, Indian, and Korean Societies for Virology, highlighted the event's significance. Additionally, past president of the American Society for Virology (ASV), formally declared the partnership between ASV and WSV during the conference.https://www.elsevier.com/locate/virology2025-03-24hj2024Medical VirologySDG-03:Good heatlh and well-bein

    Small colon impaction outbreak and associated risk factors in horses at the Onderstepoort Veterinary Academic Hospital, South Africa in 2021

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    Dissertation (MMedVet (Equine Surgery))--University of Pretoria, 2024.Background During June-July 2021, the Onderstepoort Equine Clinic experienced an increase in diffuse faecal small colon impactions (SCI). Typically, SCI is diagnosed in 1.3–3% of horses admitted to referral centres for colic. Objectives This study aimed to describe the distribution, diagnosis, treatment, and outcomes of colic cases in 2021, focusing on SCI and to identify risk factors for SCI compared to large colon impactions (LCI). Method Medical records from the Onderstepoort Veterinary Teaching Hospital were reviewed to identify colic cases in 2021 and the population distribution, diagnosis, treatment, and outcome recorded. Cases of SCI were identified and compared to LCI. Owner questionnaires assessed potential SCI risk factors. Results Colic cases(182), comprised mainly LCI(26%), large colon displacements(20%), and SCI(13%). Treatments included medical(65%), surgical(32%), or euthanasia(3%). Most horses(85%) were discharged. SCI was diagnosed in 13% of cases, higher than previously reported rates. Immediate surgical treatment was performed in 30% of cases. In the remaining cases medical management was initiated although surgical intervention was later pursued in 43% of cases. Short-term survival was 87%, with surgical cases showing higher survival (94%) than medical (67%). Stallions were at risk to develop SCI compared to “all colic” diagnoses (OR 4.17). Friesians were more likely to develop SCI compared to “all colic” (OR 7.00). Draft breed horses were more likely to develop SCI compared to compared to “all colic” (OR 8.20) and compared to LCI (OR 32.7). The study identified a risk for horses to develop SCI in winter compared to “all colic” (OR 43.2) and compared to LCI (OR 124). Conclusion A SCI outbreak occurred in 2021, with increased risks in stallions, Friesians, and draft breeds, particularly in winter. Horse owners and veterinarians should be alerted to this, especially in at-risk groups during winter. Outcomes are favourable for SCI especially when treated surgically.Companion Animal Clinical StudiesMMedVet (Equine Surgery)UnrestrictedFaculty of Veterinary Scienc

    Chemical control of the polyphagous shot hole borer beetle (PSHB, Euwallacea fornicatus) and Fusarium euwallaceae in American sweetgum (Liquidambar styraciflua)

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    DATA AVAILABILITY : The datasets generated during and/or analysed during the current study are available from the corresponding author on request.The polyphagous shot hole borer beetle (PSHB, Euwallacea fornicatus) is a pest of global significance. PSHB is an ambrosia beetle which, together with its mutualistic fungi (including Fusarium euwallaceae), can cause the death of more than 100 tree species in invaded ranges. Management of PSHB mostly relies on the removal of infested plant material. Chemical control options have been investigated only in the USA and Israel and only on a few tree species. This study evaluated four chemical treatments for the therapeutic control of PSHB on American sweetgum (Liquidambar styraciflua) in South Africa (1) bifenthrin + surfactant (alcohol ethoxylate), (2) cypermethrin + surfactant (vitamin E) + salicylic acid, (3) emamectin benzoate, and (4) propiconazole. Trees were inoculated with F. euwallaceae and mature PSHB females using a novel technique to document fungal lesion development and PSHB colony establishment success. The bifenthrin and cypermethrin treatments reduced additional PSHB colonisation attempts on treated trees by ca. 40%, while the other treatments had no effect. Colony establishment success was reduced in all treatments by between 20 and 40%. Fungal growth was inhibited only after the application of propiconazole by ca. 36%. Gallery length and the number of PSHB individuals in successful colonies were unaffected by any of the chemical treatments. These results indicate that chemical control of PSHB is only partially effective. Successful PSHB management will likely depend on a combination of chemical control options and other control strategies in an integrated pest management program.Lourensford Fruit Company. Open access funding provided by Stellenbosch University.https://link.springer.com/journal/42161hj2024BiochemistryForestry and Agricultural Biotechnology Institute (FABI)GeneticsMicrobiology and Plant PathologySDG-15:Life on lan

    Parental health risk preferences, socio-economic status and offspring's alcohol behavior in South Africa

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    DATA AVAILABILITY STATEMENT : The data for the study will be available upon reasonable request.Alcohol consumption represents a widespread behavior with detrimental effects on both individuals and society. Understanding the factors influencing offspring alcohol consumption is crucial for identifying potential risk factors and informing prevention and intervention strategies. Existing empirical literature underscores the intricate interplay of biological, environmental, and social factors in shaping offspring alcohol consumption. Building upon this foundation, this study investigates the determinants of health risk preferences, such as alcohol consumption, among South African offspring, utilizing a dataset comprising the 2008, 2010, 2012, and 2014 waves of the National Income Dynamic Study (NIDS). Logistic regressions are employed to model the determinants of offspring alcohol consumption, while ordered logits are utilized to assess the impact of parental drinking on offspring drinking frequency. The findings indicate that parental drinking significantly influences offspring alcohol intake. Specifically, daughters' alcohol consumption is influenced solely by maternal drinking, whereas sons are affected by both parents' alcohol consumption. Furthermore, while daughters from currently disadvantaged backgrounds may exhibit higher tendencies towards alcohol consumption, those with mothers from such backgrounds and fathers from more affluent backgrounds are less likely to engage in such behavior. Additionally, the results suggest that male offspring from higher-income brackets are less likely to consume alcohol, yet sons of wealthy fathers are more likely to adopt such lifestyles.https://www.cell.com/heliyonhj2024EconomicsSDG-03:Good heatlh and well-bein

    A quasi-geostrophic analysis of summertime southern African linear-regime westerly waves

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    DATA AVAILABILITY : All the data used in the study was obtained are the Fifth Generation European Centre for Medium-Range Weather Forecasts reanalysis (ERA5) can be obtained from https://www.ecmwf.int/en/forecasts/datasets/reanalysis-datasets/era5.Please read abstract in the article.The Water Research Foundation of South Africa.http://link.springer.com/journal/382hj2024Geography, Geoinformatics and MeteorologySDG-13:Climate actio

    Molecular characterization of Listeria spp. isolated from cattle farms, abattoirs, and beef products in Mpumalanga and North-West Provinces, South Africa

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    Thesis (PhD (Production Animal Studies))--University of Pretoria, 2024.Listeria monocytogenes is a foodborne pathogen that has serious public health implications. Since the advent of the largest outbreak of listeriosis in South Africa, it has become important to understand the genomic characteristics of L. monocytogenes from food products. This study aimed to use molecular techniques to characterize Listeria isolates (n=214) recovered from cattle farms, beef and beef-based products from retails. PCR was used to classify the isolates into Listeria species. The identified L. monocytogenes were further classified into serogroups and Multilocus Variable-Number Tandem Repeat Analysis (MLVA) types using conventional PCR protocols. Likewise, L. innocua (165) isolates were also typed using MLVA. As the only pathogenic species identified in this study, L. monocytogenes was further characterized using whole genome sequencing (WGS) and bioinformatics tools to determine the population structure, antimicrobial resistance genes, virulence profile, mobile genetic elements (plasmids, prophages), genomic islands, insertion sequences, the type VII secretion system, and sortases. Listeria isolates were classified into L. innocua (77.10%, n=165), L. monocytogenes (11.21%, n=24), L. welshimeri (5.61%, n=12), L. grayi (1.40%, n=3), L. seeligeri (0.93%, n=2), and L. species (3.73%, n=8). L. monocytogenes serogroups determined by PCR were: IVb (4b-4d-4e) (37.50%), IIa (1/2a-3a) (29.16%), IIb (1/2b-3b) (12.50%), IIc (1/2c-3c) (8.33%), and IVb-1 (4.16%). MLVA was able to cluster L. monocytogenes isolates into 10 MLVA types and L. innocua into 34 MLVA types based on their relatedness. The isolates clustered irrespective of sample category, geographical origin and serogroup for L. monocytogenes. Multilocus Sequence Type (MLST) analysis revealed that ST204 of CC204 (Lineage II, serogroup IIa (1/2a, 3a) was the most common sequence type (ST). Other sequence types detected included ST1 of CC1 (Lineage I, serogroups IVb (4b,4d,4e), ST5 of CC5 (Lineage I, serogroup IIb (1/2b,3b,7), ST9 of CC9 (Lineage II, serogroup IIc (2c, 3c), ST88 of CC88 (Lineage I, serogroup IIb (1/2b,3b,7), ST876 of CC1, (Lineage II, serogroup IVb (4b,4d,4e), ST2 of CC2 (Lineage I, serogroup IVb (4b, 4d, 4e), ST321 of CC321 (Lineage II, serogroup IIa (1/2a, 3a) and ST1430 of CC2 (Lineage I, serogroup IVb (4b,4d,4e). All the L. monocytogenes STs carried four intrinsic resistance genes, fosX, lin, norB, and mprF, conferring resistance to antimicrobials, fosfomycin, lincosamide, quinolones, and cationic peptides, respectively. Genes encoding for virulence factors LIPI-1 (pfrA-hly-plcA-plcB-mpl-ActA) and internalin genes inlABCJKF, were present in most STs. Prophages profile, vB_LmoS_188, was overrepresented amongst the isolates, followed by LP_101, LmoS_293_028989, LP_030_2_021539, A006 and LP_HM00113468. Plasmid pLGUG1 (40%) was the most represented and only found in ST204 types. Similarly, plasmid J1776 (40%) was also significantly represented amongst the STs, followed by pLI100 (13%), and pLM5578 (7%). Mobile genetic elements did not harbour any virulence or resistance genes. Listeria genomic island 2 (LGI-2) was found present in all the isolates, whilst Listeria genomic island 3 (LGI-3) was present in a subset of isolates (25%). The type VII secretion system was found in 42% of the isolates, and sortase A was found in all L. monocytogenes genomes. This study revealed that non-pathogenic and pathogenic Listeria spp. could be contaminants of meat products and the farm environment. The strains of L. innocua and L. monocytogenes displayed diversity even though they all originated from bovine samples. MLVA proved to be an affordable, simple, and discriminatory method that can be used routinely to type L. monocytogenes and L. innocua isolates. The isolates did not carry genes conferring resistance to first-line drugs used against listeriosis and, therefore, did not pose a threat to antimicrobial therapy. Characterization of L. monocytogenes in the current study highlighted the virulence capability of L. monocytogenes and the risk posed to the public by this pathogen, as it is often found in food and food processing environments.Production Animal StudiesPhD (Production Animal Studies)UnrestrictedFaculty of Natural and Agricultural Science

    Second to none: Second cities and next cities as Africa's engine of prosperity

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    Cities are already the locus of 80% of global GDP and home to more than half of the world’s population. Further, the United Nations (UN) anticipates that the world’s urban population will grow to 6.7 billion in 2050 from a base of just 4.2 billion in 2018, with close to 90% of this increase taking place in Asia and Africa. This means populations across major cities will grow at unprecedented rates. But it is not just capitals and megacities that face great challenges and opportunities. Often overshadowed by their more renowned counterparts, the multitude of smaller cities are poised to play a critical role in the unfolding demographic shift. Second cities provide a cultural and economic bridge between rural areas and big cities. They are often levers for regional and global trade. In the African context, the narrative of urbanisation is rapidly evolving, with second cities emerging as dynamic hubs of innovation, opportunity, and resilience. Africa’s second cities embody a rich tapestry of diversity, reflecting the continent’s multifaceted identity and historical legacy. From vital logistics and shipping hubs like Mozambique’s Beira, to the academic centre that is Rabat in Morocco, to the Democratic Republic of the Congo’s mining fulcrum of Lubumbashi and the tourism gem in South Africa’s crown that is Cape Town, second cities take a multitude of forms, while sharing important traits. In partnership with the GIBS Centre for African Management and Markets (CAMM), DHL Express SSA has embarked on this research paper to understand the complexities of and opportunities that lie in these urban centres across sub-Saharan Africa. The paper captures the unique potential for Africa’s second cities to take advantage of the so-called demographic dividend and generate prosperity for the continent. This paper rounds out with a selection of evidence-based approaches that business leaders and policymakers can wield to address the challenges that second cities face and, indeed, FOREWORD leverage powerful demographic, social and economic forces to build a better continent for tomorrow. I extend my sincere appreciation to the authors of this research paper for their dedication, insight, and scholarly rigour. Their work represents a significant contribution to our understanding of Africa’s urban landscape, laying the groundwork for further analysis and action. This paper is designed to open dialogue, collaboration, and positive change, inspiring us to unlock the full potential of Africa’s second cities.pagibs202

    Price effects after one-day abnormal returns and crises in the stock markets

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    DATA AVAILABILITY: Data will be made available on request.We investigate price effects after one-day abnormal returns during crises in US, Japanese, Chinese, Russian and Brazilian stock markets, using the ANOVA, Mann–Whitney, t-tests, the modified cumulative abnormal return approach, regression analysis with dummy variables, and the trading simulation approach. The results suggest that the momentum effect is the most typical case of price behaviour after the days with positive abnormal returns, especially in emerging markets in pre and post crisis periods. Interestingly the momentum effect in developed markets changes into contrarian during crisis periods. However, in emerging markets the momentum effect prevails even in crisis periods. However, the power of the detected effects is weak. These effects do not provide opportunities to beat the market and might result from prevailing positive returns in these stock markets.http://www.elsevier.com/locate/ribafhj2024EconomicsSDG-08:Decent work and economic growt

    Broad-scale genetic assessment of southern ground-hornbills (Bucorvus leadbeateri) to inform population management

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    DATA AVAILABILITY : Bucorvus leadbeateri sequences are available on GenBank, accession numbers: OP046521-OP046574, and OP122231 - OP122407.The Southern Ground-hornbill (SGH) (Bucorvus leadbeateri) is considered an umbrella species for biodiversity conservation in savannah biomes since they require large territories and significant protection measures that help to conserve a wide range of biodiversity with similar savanna and grassland requirements. Declines of the species are attributed to low reproductive rates coupled with multiple anthropogenic threats, including secondary poisoning, and persecution. Little is known about connectivity and population structure of SGH populations in Africa, south of the equator. Knowledge of population differentiation is needed to ensure that targeted conservation management plans can be implemented to slow population declines and ensure survival of the species. To inform a long-term conservation strategy, we investigated the broad-scale population structure of Southern Ground-hornbill across their sub-equatorial range. Our study based on 16 microsatellite loci identified moderate variation (average of 5.889 alleles per locus and a mean observed heterozygosity of 0.546) similar to other long-lived avian species. In contrast, mitochondrial DNA sequences analysis identified low diversity (Hd = 0.3313, π = 0.0015). A Bayesian assignment approach, principal component analysis, analysis of molecular variance and phylogenetic analysis identified weak to moderate population structuring across long distances and mitochondrial data showed a shallow phylogeny. Restriction to long-distance dispersal was detected that could not be attributed to isolation by distance, suggesting that other factors, such as their dispersal biology, are shaping the observed genetic differentiation. Although our study does not support the designation of populations as independent conservation units, we advocate that population management should continue to follow the Precautionary Principle (mixing founders from the same range state, rather than allowing mixing of founders from the extremes of the range) until there is scientific certainty. Following further research, if no independent conservation units are detected, then the global captive population can contribute to reintroductions across the range. In the wild, populations at the edge of the species range may need additional management strategies and gene flow should be promoted between neighbouring populations.https://www.elsevier.com/locate/geccohj2024BiochemistryGeneticsMicrobiology and Plant PathologySDG-15:Life on lan

    Activities as the critical link between motivation and destination choice in cultural tourism

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    PURPOSE : This study aimed to determine the motivations of a select group of South Africans in terms of their potential engagement with cultural tourism; more specifically, the study set out to show whether these motivations influence the cultural activities that the tourists want to participate in and whether their interest in specific cultural activities determines their destination choices. Furthermore, the mediating role of activities in the relationship between cultural motivations and destination choice was also assessed. DESIGN/METHODOLOGY/APPROACH : An online panel survey collected responses from 1,530 potential cultural tourists across South Africa. Hypotheses were tested, using structural equation modelling. FINDINGS : The results show that tourists' motivations for cultural tourism influence their likelihood of participating in specific cultural activities. Cultural tourism is shown to be influenced by more than learning and includes entertainment, relaxation, novelty and escape dimensions. There also seems to be a difference in the activities engaged in by destination type. For example, tourists likely to take part in indigenous cultural tourism activities are more likely to do so at hedonic destinations. PRACTICAL IMPLICATIONS : This paper contributes to the understanding of cultural tourism activities, aiding destinations in attracting cultural tourists. Destinations need to develop activities that match visitor motivations, increase satisfaction and encourage visitors to return. ORIGINALITY/VALUE : The paper increases the understanding of cultural tourism in South Africa and underlines the importance of communities in providing distinctive tourism activities. The study also has an important social dimension, highlighting the role of social status in cultural tourism consumption and destination selection.https://www.emerald.com/insight/publication/issn/2514-9792hj2024Tourism ManagementSDG-11:Sustainable cities and communitie

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