52 research outputs found
Ethics beyond the code of conduct - understanding the ethical dilemmas of entrepreneurs
Entrepreneurs choose a particular way of life with the dual aim of maximising profit and gaining a sense of self-satisfaction. In these endeavours, entrepreneurs typically live with the threat of competition and the risk of business failure, while attempting to do their best within the limitations of their resources. This qualitative study first examines existing theories of ethics and ways of applying business ethics and thereafter investigates entrepreneurs' actual experiences by means of in-depth interviews and the use of phenomenology. It finds that entrepreneurs are not guided by any specific code of conduct, and must decide for themselves what is right. It describes the entrepreneurial business ethic, some of the types of dilemmas that they experience and the methods that they have developed to deal with the dilemmas
How entrepreneurs deal with ethical challenges : an application of the Business Ethics Synergy Star Technique
Entrepreneurs typically live with the ever present threat of business failure arising from limited financial resources and aggressive competition in the marketplace. Under these circumstances, conflicting priorities arise and the entrepreneur is thus faced with certain dilemmas. In seeking to resolve these, entrepreneurs must often rely on their own judgment to determine ‘‘what is right’’. There is thus a need for a technique to assist them decide on a course of action when no precedent or obvious solution exists. This research paper examines how entrepreneurs experience and deal with these dilemmas. The research is based on interviews with seven entrepreneurs in established service-oriented ventures, which gave rise to 26 dilemmas. These dilemmas were analyzed by making use of the Synergy Star technique, which is introduced here as a tool that is useful in defining any dilemma, isolating the ethical component, and resolving the dilemma in a way that is congruent with the entrepreneur’s personal world-view
Documenting the microbiome diversity and distribution in selected fleas from South Africa with an emphasis on the cat flea, Ctenocephalides f. felis.
The factors that influence parasite associated bacterial microbial diversity and the geographic distributions of bacteria are not fully understood. In an effort to gain a deeper understanding of the relationship between the bacterial diversity of Ctenocephalides fleas and host species and the external environment, we conducted a metagenetic analysis of 107 flea samples collected from 8 distinct sampling sites in South Africa. Pooled DNA samples mostly comprising of 2 or 3 individuals sampled from the same host, and belonging to the same genetic cluster, were sequenced using the Ion PGMâ„¢ Hi-Qâ„¢ Kit and the Ion 316â„¢ Chip v2. Differences were detected in the microbiome compositions between Ctenocephalides felis, Ctenocephalides canis and Ctenocephalides connatus. Although based on a small sample, C. connatus occurring on wildlife harboured a higher bacterial richness when compared to C. felis on domestic animals. Intraspecific differences in the microbial OTU diversity were detected within C. f. felis that occurred on domestic cats and dogs. Different genetic lineages of C. f. felis were similar in microbial compositions but some differences exist in the presence or absence of rare bacteria. Rickettsia and Bartonella OTU's identified in South African cat fleas differ from those identified in the USA and Australia. Intraspecific microbial compositions also differ across geographic sampling sites. Generalized dissimilarity modelling showed that temperature and humidity are potentially important environmental factors explaining the pattern obtained
Trialling meta-research in comparative cognition: claims and statistical inference in animal physical cognition
Scientific disciplines face concerns about replicability and statistical inference, and these concerns are also relevant in animal cognition research. This paper presents a first attempt to assess how researchers make and publish claims about animal physical cognition, and the statistical inferences they use to support them. We surveyed 116 published experiments from 63 papers on physical cognition, covering 43 different species. The most common tasks in our sample were trap-tube tasks (14 papers), other tool use tasks (13 papers), means-end understanding and string-pulling tasks (11 papers), object choice and object permanence tasks (9 papers) and access tasks (5 papers). This sample is not representative of the full scope of physical cognition research; however, it does provide data on the types of statistical design and publication decisions researchers have adopted. Across the 116 experiments, the median sample size was 7. Depending on the definitions we used, we estimated that between 44% and 59% of our sample of papers made positive claims about animals’ physical cognitive abilities, between 24% and 46% made inconclusive claims, and between 10% and 17% made negative claims. Several failures of animals to pass physical cognition tasks were reported. Although our measures had low inter-observer reliability, these findings show that negative results can and have been published in the field. However, publication bias is still present, and consistent with this, we observed a drop in the frequency of p-values above .05. This suggests that some non-significant results have not been published. More promisingly, we found that researchers are likely making many correct statistical inferences at the individual-level. The strength of evidence of statistical effects at the group-level was weaker, and its p-value distribution was consistent with some effect sizes being overestimated. Studies such as ours can form part of a wider investigation into statistical reliability in comparative cognition. However, future work should focus on developing the validity and reliability of the measurements they use, and we offer some starting points
Despite delayed kinetics, people living with HIV achieve equivalent antibody function after SARS-CoV-2 infection or vaccination
DATA AVAILABILITY STATEMENT : The original contributions presented in the study are included
in the article/Supplementary Material. Further inquiries can be
directed to the corresponding authors.The kinetics of Fc-mediated functions following SARS-CoV-2 infection or
vaccination in people living with HIV (PLWH) are not known. We compared
SARS-CoV-2 spike-specific Fc functions, binding, and neutralization in PLWH
and people without HIV (PWOH) during acute infection (without prior
vaccination) with either the D614G or Beta variants of SARS-CoV-2, or
vaccination with ChAdOx1 nCoV-19. Antiretroviral treatment (ART)–naïve
PLWH had significantly lower levels of IgG binding, neutralization, and
antibody-dependent cellular phagocytosis (ADCP) compared with PLWH on
ART. The magnitude of antibody-dependent cellular cytotoxicity (ADCC),
complement deposition (ADCD), and cellular trogocytosis (ADCT) was
differentially triggered by D614G and Beta. The kinetics of spike IgG-binding
antibodies, ADCC, and ADCD were similar, irrespective of the infecting variant
between PWOH and PLWH overall. However, compared with PWOH, PLWH
infected with D614G had delayed neutralization and ADCP. Furthermore, Beta
infection resulted in delayed ADCT, regardless of HIV status. Despite these
delays, we observed improved coordination between binding and neutralizing
responses and Fc functions in PLWH. In contrast to D614G infection, binding
responses in PLWH following ChAdOx-1 nCoV-19 vaccination were delayed,
while neutralization and ADCP had similar timing of onset, but lower magnitude,The South African National Research Foundation, the Poliomyelitis Research Foundation, the University of the Witwatersrand, the South African Research Chairs Initiative of the Department of Science and Innovation, the SA Medical Research Council SHIP program, the Centre for the AIDS Program of Research (CAPRISA), the Bill and Melinda Gates Foundation through the Global Immunology and Immune Sequencing for Epidemic Response (GIISER) program, the Wellcome Trust [226137/Z/22/Z] and the HORIZON programme supported by the European Union.http://www.frontiersin.org/Immunologyam2024ImmunologyInternal MedicineSDG-03:Good heatlh and well-bein
Comparative phylogeography of parasitic Laelaps mites contribute new insights into the specialist-generalist variation hypothesis (SGVH)
BACKGROUND: The specialist-generalist variation hypothesis (SGVH) in parasites suggests that, due to patchiness in
habitat (host availability), specialist species will show more subdivided population structure when compared to
generalist species. In addition, since specialist species are more prone to local stochastic extinction events with their
hosts, they will show lower levels of intraspecific genetic diversity when compared to more generalist.
RESULTS: To test the wider applicability of the SGVH we compared 337 cytochrome oxidase I mitochondrial DNA and
268 nuclear tropomyosin DNA sequenced fragments derived from two co-distributed Laelaps mite species and
compared the data to 294 COI mtDNA sequences derived from the respective hosts Rhabdomys dilectus, R. bechuanae,
Mastomys coucha and M. natalensis. In support of the SGVH, the generalist L. muricola was characterized by a high
mtDNA haplotypic diversity of 0.97 (±0.00) and a low level of population differentiation (mtDNA Fst= 0.56, p < 0.05;
nuDNA Fst = 0.33, P < 0.05) while the specialist L. giganteus was overall characterized by a lower haplotypic diversity of
0.77 (±0.03) and comparatively higher levels of population differentiation (mtDNA Fst = 0.87, P < 0.05; nuDNA Fst = 0.48,
P < 0.05). When the two specialist L. giganteus lineages, which occur on two different Rhabdomys species, are
respectively compared to the generalist parasite, L. muricola, the SGVH is not fully supported. One of the specialist L.
giganteus species occurring on R. dilectus shows similar low levels of population differentiation (mtDNA Fst= 0.53, P < 0.
05; nuDNA Fst= 0.12, P < 0.05) than that found for the generalist L. muricola. This finding can be correlated to
differences in host dispersal: R. bechuanae populations are characterized by a differentiated mtDNA Fst of 0.79 (P < 0.05)
while R. dilectus populations are less structured with a mtDNA Fst= 0.18 (P < 0.05).
CONCLUSION: These findings suggest that in ectoparasites, host specificity and the vagility of the host are both
important drivers for parasite dispersal. It is proposed that the SGHV hypothesis should also incorporate reference to
host dispersal since in our case only the specialist species who occur on less mobile hosts showed more subdivided
population structure when compared to generalist species
Shared N417-dependent epitope on the SARS-CoV-2 Omicron, Beta, and Delta Plus variants
As severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) continues to evolve, several variants of concern (VOCs) have arisen which are defined by multiple mutations in their spike proteins. These VOCs have shown variable escape from antibody responses and have been shown to trigger qualitatively different antibody responses during infection. By studying plasma from individuals infected with either the original D614G, Beta, or Delta variants, we showed that the Beta and Delta variants elicit antibody responses that are overall more cross-reactive than those triggered by D614G. Patterns of cross-reactivity varied, and the Beta and Delta variants did not elicit cross-reactive responses to each other. However, Beta-elicited plasma was highly cross-reactive against Delta Plus (Delta+), which differs from Delta by a single K417N mutation in the receptor binding domain, suggesting that the plasma response targets the N417 residue. To probe this further, we isolated monoclonal antibodies from a Beta-infected individual with plasma responses against Beta, Delta+, and Omicron, which all possess the N417 residue. We isolated an N417-dependent antibody, 084-7D, which showed similar neutralization breadth to the plasma. The 084-7D MAb utilized the IGHV3-23*01 germ line gene and had somatic hypermutations similar to those of previously described public antibodies which target the 417 residue. Thus, we have identified a novel antibody which targets a shared epitope found on three distinct VOCs, enabling their cross-neutralization. Understanding antibodies targeting escape mutations, such as K417N, which repeatedly emerge through convergent evolution in SARS-CoV-2 variants, may aid in the development of next-generation antibody therapeutics and vaccines.
IMPORTANCE : The evolution of SARS-CoV-2 has resulted in variants of concern (VOCs) with distinct spike mutations conferring various immune escape profiles. These variable mutations also influence the cross-reactivity of the antibody response mounted by individuals infected with each of these variants. This study sought to understand the antibody responses elicited by different SARS-CoV-2 variants and to define shared epitopes. We show that Beta and Delta infections resulted in antibody responses that were more cross-reactive than the original D614G variant, but they had differing patterns of cross-reactivity. We further isolated an antibody from Beta infection which targeted the N417 site, enabling cross-neutralization of Beta, Delta+, and Omicron, all of which possess this residue. The discovery of antibodies which target escape mutations common to multiple variants highlights conserved epitopes to target in future vaccines and therapeutics.The South African Research Chairs Initiative of the Department of Science and Innovation, the National Research Foundation of South Africa, the SA Medical Research Council SHIP program and the Bill and Melinda Gates Foundation, through the Global Immunology and Immune Sequencing for Epidemic Response (GIISER) program.https://journals.asm.org/journal/jvihj2023ImmunologyInternal Medicin
Antibody-dependent cellular cytotoxicity against SARS-CoV-2 Omicron sub-lineages is reduced in convalescent sera regardless of infecting variant
The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) Omicron BA.4 and BA.5 variants caused
major waves of infections. Here, we assess the sensitivity of BA.4 to binding, neutralization, and antibodydependent
cellular cytotoxicity (ADCC) potential, measured by FcgRIIIa signaling, in convalescent donors
infected with four previous variants of SARS-CoV-2, as well as in post-vaccination breakthrough infections
(BTIs) caused by Delta or BA.1. We confirm that BA.4 shows high-level neutralization resistance regardless
of the infecting variant. However, BTIs retain activity against BA.4, albeit at reduced titers. BA.4 sensitivity to
ADCC is reduced compared with other variants but with smaller fold losses compared with neutralization and
similar patterns of cross-reactivity. Overall, the high neutralization resistance of BA.4, even to antibodies
from BA.1 infection, provides an immunological mechanism for the rapid spread of BA.4 immediately after
a BA.1-dominated wave. Furthermore, although ADCC potential against BA.4 is reduced, residual activity
may contribute to observed protection from severe disease.The South African Research Chairs Initiative of the Department of Science and Innovation and National Research Foundation of South Africa, the South African Medical Research Council SHIP program, the European Union-Africa Concerted Action on SAR-CoV-2 Virus Variant and Immunological Surveillance (CoVICIS) consortium, and the Centre for the AIDS Programme of Research in South Africa (CAPRISA), the Bill and Melinda Gates Foundation through the Global Immunology and Immune Sequencing for Epidemic Response (GIISER) program.https://www.cell.com/cell-reports-medicine/homeam2024ImmunologyInternal MedicineSDG-03:Good heatlh and well-bein
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