Protest blues : public opinion on the policing of protest in South Africa

Abstract: The policing response to rising protest action in the country has received increased attention in the last decade. This is particularly due to concerns over confrontations during which protestors have been arrested, injured and in some instances killed by the police. Despite the criticism voiced by various stakeholders about the manner in which the police manage crowd gatherings, relatively little is known about the views of South African adults on the policing of protest action and the factors that shape such attitudes. To provide some insight, the study presented in this article draws on data from a specialized module on protest‐related attitudes and behaviour that was fielded as part of the 2016 round of the Human Sciences Research Council’s South African Social Attitudes Survey (SASAS) series. This nationally representative survey included specific questions probing the public’s overall evaluation of the performance of the police in dealing with protests and the justifiability of the use of force in policing protest action. The paper will present the national pattern of results based on these measures and then determine the extent to which there exist distinct underlying socio‐demographic cleavages. A combination of bivariate and multivariate analysis will also be undertaken to provide an understanding of the role of the perceived effectiveness, acceptability and reported participation in protest (especially disruptive and violent actions) in shaping views regarding policing protest. The article concludes with a discussion that reflects on the implications of the research for the policing of protest action in future, taking into account the appreciable rise in the incidence of protest since the mid‐2000s as well as the mounting tensions between state institutions and communities over the political, moral and constitutional arguments for and against such actions

‘Unexpected item in the bagging area’: Anomaly Detection in X-ray Security Images

The role of Anomaly Detection in X-ray security imaging, as a supplement to targeted threat detection, is described; and a taxonomy of anomalies types in this domain is presented. Algorithms are described for detecting appearance anomalies, of shape, texture and density; and semantic anomalies of object category presence. The anomalies are detected on the basis of representations extracted from a convolutional neural network pre-trained to identify object categories in photographs: from the final pooling layer for appearance anomalies, and from the logit layer for semantic anomalies. The distribution of representations in normal data are modelled using high-dimensional, full-covariance, Gaussians; and anomalies are scored according to their likelihood relative to those models. The algorithms are tested on X-ray parcel images using stream-of-commerce data as the normal class, and parcels with firearms present as examples of anomalies to be detected. Despite the representations being learnt for photographic images, and the varied contents of stream-of-commerce parcels; the system, trained on stream-of-commerce images only, is able to detect 90% of firearms as anomalies, while raising false alarms on 18% of stream-of-commerce

Origin of Life

The evolution of life has been a big enigma despite rapid advancements in the fields of biochemistry, astrobiology, and astrophysics in recent years. The answer to this puzzle has been as mind-boggling as the riddle relating to evolution of Universe itself. Despite the fact that panspermia has gained considerable support as a viable explanation for origin of life on the Earth and elsewhere in the Universe, the issue remains far from a tangible solution. This paper examines the various prevailing hypotheses regarding origin of life like abiogenesis, RNA World, Iron-sulphur World, and panspermia; and concludes that delivery of life-bearing organic molecules by the comets in the early epoch of the Earth alone possibly was not responsible for kick-starting the process of evolution of life on our planet.Comment: 32 pages, 8 figures,invited review article, minor additio

Literature Review to Support a Survey to Understand the Socio-economic, Wellbeing and Human Rights Related Experiences of People with Disabilities During Covid-19 Lockdown in South Africa

COVID-19 pandemic and associated national responses have had ramifications for societies around the world, including South Africa. The marginalisation of people with disabilities is well documented in pre-COVID times, and emerging evidence suggests that the crisis has made this worse, as well as presenting new challenges for people with disabilities. This paper presents a review of published research and grey literature of relevance to the proven or anticipated socio-economic, wellbeing and human right related impacts of COVID-19 on people with disabilities in South Africa and other contexts. Its purpose is to summarise evidence to inform a study on the experiences of South Africans with disabilities during the COVID-19 pandemic and the development of an improved inclusive framework for future management of such crises in South Africa. After a brief introduction, the paper is structured around four main sections. Context is provided by considering COVID-19 and disability both globally and in Africa. Then the literature focused on Humanitarian Disaster Risk Reduction and disability inclusion is discussed. Finally the South African policy and legislation environment on disability and humanitarian action is explored. The review finds that globally there is a limited but growing body of work on COVID-19 and disability. There is a particular dearth of evidence focusing specifically on Africa. The evidence that does exist tends either to be focused on a few particular countries or form part of large global surveys. Much of the global level grey literature published early in the pandemic and subsequently anticipates exacerbated negative experiences for people with disabilities, including exclusion from services, stigma and discrimination and lack of inclusive approaches to relief and support by governments and others. Advisory materials, sometimes focussed on specific subgroups, are generally in agreement about calling for a universally inclusive and disability aware approach to pandemic mitigation across settings and sectors. The limited primary research on COVID-19 and disability is mostly focussed on high income settings and or populations with particular health concerns

Spin-polarized 3He nuclear targets and metastable 4He atoms by optical pumping with a tunable, Nd:YAP laser

Several Nd:YAP lasers were constructed which could be broadly tuned in the 1083-nm region which includes the helium 23S-23P transition, using a Lyot filter and thin, uncoated etalons within the laser cavity. 1 W of power could be extracted at 1083 nm through a 1% transmitting output coupler. This laser beam was used to optically pump metastable 4He and 3He 23S helium atoms in a weak discharge cell, spin polarizing the metastable ensemble. In a 3He cell the polarization is transferred to the nuclear spin system. A 3He target cell at 0.3 Torr was polarized to 52% in a few minutes. We describe the application of this system to the design of polarized targets for experiments in nuclear physics

Combined molnupiravir-nirmatrelvir treatment improves the inhibitory effect on SARS-CoV-2 in macaques

The periodic emergence of SARS-CoV-2 variants of concern (VOCs) with unpredictable clinical severity and ability to escape preexisting immunity emphasizes the continued need for antiviral interventions. Two small molecule inhibitors, molnupiravir (MK-4482), a nucleoside analog, and nirmatrelvir (PF-07321332), a 3C-like protease inhibitor, have recently been approved as monotherapy for use in high-risk patients with COVID-19. As preclinical data are only available for rodent and ferret models, here we assessed the efficacy of MK-4482 and PF-07321332 alone and in combination against infection with the SARS-CoV-2 Delta VOC in the rhesus macaque COVID-19 model. Macaques were infected with the SARS-CoV-2 Delta variant and treated with vehicle, MK-4482, PF-07321332, or a combination of MK-4482 and PF-07321332. Clinical exams were performed at 1, 2, and 4 days postinfection to assess disease and virological parameters. Notably, use of MK-4482 and PF-07321332 in combination improved the individual inhibitory effect of both drugs, resulting in milder disease progression, stronger reduction of virus shedding from mucosal tissues of the upper respiratory tract, stronger reduction of viral replication in the lower respiratory tract, and reduced lung pathology. Our data strongly indicate superiority of combined MK-4482 and PF-07321332 treatment of SARS-CoV-2 infections as demonstrated in the closest COVID-19 surrogate model of human infection

Genome wide single cell analysis of chemotherapy resistant metastatic cells in a case of gastroesophageal adenocarcinoma

<p>Abstract</p> <p>Background</p> <p>Metastatic progression due to development or enrichment of therapy-resistant tumor cells is eventually lethal. Molecular characterization of such chemotherapy resistant tumor cell clones may identify markers responsible for malignant progression and potential targets for new treatment. Here, in a case of stage IV adenocarcinoma of the gastroesophageal junction, we report the successful genome wide analysis using array comparative genomic hybridization (CGH) of DNA from only fourteen tumor cells using a bead-based single cell selection method from a bone metastasis progressing during chemotherapy.</p> <p>Case presentation</p> <p>In a case of metastatic adenocarcinoma of the gastroesophageal junction, the progression of bone metastasis was observed during a chemotherapy regimen of epirubicin, oxaliplatin and capecitabine, whereas lung-, liver and lymph node metastases as well as the primary tumor were regressing. A bone marrow aspirate sampled at the site of progressing metastasis in the right iliac bone was performed, and single cell molecular analysis using array-CGH of Epithelial Specific Antigen (ESA)-positive metastatic cells, and revealed two distinct regions of amplification, 12p12.1 and 17q12-q21.2 amplicons, containing the KRAS (12p) and ERBB2 (HER2/NEU) (17q) oncogenes. Further intrapatient tumor heterogeneity of these highlighted gene copy number changes was analyzed by fluorescence in situ hybridization (FISH) in all available primary and metastatic tumor biopsies, and ErbB2 protein expression was investigated by immunohistochemistry.</p> <p>ERBB2 was heterogeneously amplified by FISH analysis in the primary tumor, as well as liver and bone metastasis, but homogenously amplified in biopsy specimens from a progressing bone metastasis after three initial cycles of chemotherapy, indicating a possible enrichment of erbB2 positive tumor cells in the progressing bone marrow metastasis during chemotherapy. A similar amplification profile was detected for wild-type KRAS, although more heterogeneously expressed in the bone metastasis progressing on chemotherapy. Correspondingly, the erbB2 protein was found heterogeneously expressed by immunohistochemical staining of the primary tumor of the gastroesophageal junction, while negative in liver and bone metastases, but after three initial cycles of palliative chemotherapy with epirubicin, oxaliplatin and capecetabine, the representative bone metastasis stained strongly positive for erbB2.</p> <p>Conclusion</p> <p>Global analysis of genetic aberrations, as illustrated by performing array-CGH analysis on genomic DNA from only a few selected tumor cells of interest sampled from a progressing bone metastasis, can identify relevant therapeutic targets and genetic aberrations involved in malignant progression, thus emphasizing the importance and feasibility of this powerful tool on the road to more personalized cancer therapies in the future.</p

Sleep quality, the neglected outcome variable in clinical studies focusing on locomotor system; a construct validation study

Background: In addition to general health and pain, sleep is highly relevant to judging the well-being of an individual. Of these three important outcome variables, however, sleep is neglected in most outcome studies. Sleep is a very important resource for recovery from daily stresses and strains, and any alteration of sleep will likely affect mental and physical health, especially during disease. Sleep assessment therefore should be standard in all population-based or clinical studies focusing on the locomotor system. Yet current sleep assessment tools are either too long or too specific for general use. Methods: Based on a literature review and subsequent patient-based rating of items, an expert panel designed a four-item questionnaire about sleep. Construct validation of the questionnaire in a random sample of the German-speaking Swiss population was performed in 2003. Reliability, correlation, and tests for internal consistency and validity were analyzed. Results: Overall, 16,634 (70%) out of 23,763 eligible individuals participated in the study. Test-retest reliability coefficients ranged from 0.72 to 0.87, and a Cronbach’s alpha of 0.83 indicates good internal consistency. Results show a moderate to good correlation between sleep disturbances and health perception, and between sleep disturbances and overall pain. Conclusions: The Sleep Standard Evaluation Questionnaire (SEQ-Sleep) is a reliable and short tool with confirmed construct validity for sleep assessment in population-based observational studies. It is easy to administer and therefore suitable for postal surveys of the general population. Criterion validity remains to be determined

Dietary antioxidants protect gut epithelial cells from oxidant-induced apoptosis

BACKGROUND: The potential of ascorbic acid and two botanical decoctions, green tea and cat's claw, to limit cell death in response to oxidants were evaluated in vitro. METHODS: Cultured human gastric epithelial cells (AGS) or murine small intestinal epithelial cells (IEC-18) were exposed to oxidants – DPPH (3 μM), H(2)O(2) (50 μM), peroxynitrite (300 μM) – followed by incubation for 24 hours, with antioxidants (10 μg/ml) administered as a 1 hour pretreatment. Cell number (MTT assay) and death via apoptosis or necrosis (ELISA, LDH release) was determined. The direct interactions between antioxidants and DPPH (100 μM) or H(2)O(2) (50 μM) were evaluated by spectroscopy. RESULTS: The decoctions did not interact with H(2)O(2), but quenched DPPH although less effectively than vitamin C. In contrast, vitamin C was significantly less effective in protecting human gastric epithelial cells (AGS) from apoptosis induced by DPPH, peroxynitrite and H(2)O(2) (P < 0.001). Green tea and cat's claw were equally protective against peroxynitrite and H(2)O(2), but green tea was more effective than cat's claw in reducing DPPH-induced apoptosis (P < 0.01). Necrotic cell death was marginally evident at these low concentrations of peroxynitrite and H(2)O(2), and was attenuated both by cat's claw and green tea (P < 0.01). In IEC-18 cells, all antioxidants were equally effective as anti-apoptotic agents. CONCLUSIONS: These results indicate that dietary antioxidants can limit epithelial cell death in response to oxidant stress. In the case of green tea and cat's claw, the cytoprotective response exceed their inherent ability to interact with the injurious oxidant, suggestive of actions on intracellular pathways regulating cell death