Rapid fabrication of ultra-smooth Y-TZP bioceramic surfaces by dual-axis wheel polishing : process development and tribological characterization

The existing artificial joint implants using bioceramic materials face problems of difficulty in manufacturing and premature failure due to wear. This paper investigated a rapid preparing process of ultra-smooth surfaces of yttria-stabilized tetragonal zirconia polycrystal bioceramics based on the dual-axis wheel polishing (DAWP) system. Friction and wear tests were conducted to prove that the prepared ultra-smooth surface can effectively reduce wear. The effects of process parameters on polishing performances were investigated. The XRD and SEM analysis and micro-hardness testing were used to characterize the prepared surface in material behaviors. Tribological tests were carried out on a ball-on-plate reciprocating tribometer to comparatively study the tribological behavior and wear mechanism of the prepared ultra-smooth surfaces and the conventional surface at sub-microscale. The used finishing technology can steadily achieve fast preparation of ultra-smooth bioceramic surfaces, and with a high material removal rate (the highest value was 1.14 mg/min). Besides, in contrast to the conventional surface (Ra 129 nm), the prepared ultra-smooth surface (Ra 0.38 nm) achieved a much smaller friction coefficient, and much less wear volume, indicating that the wear resistance of the ultra-smooth surface was significantly improved

A multi-stakeholder strategy to identify conservation priorities in Peninsular Malaysia

Malaysia, with its rapidly growing economy, exemplifies the tensions between conservation and development faced by many tropical nations. Here we present the results of a multi-stakeholder engagement exercise conducted to (1) define conservation priorities in Peninsular Malaysia and (2) explore differences in perceptions among and within stakeholder groups (i.e. government, academia, NGOs and the private sector). Our data collection involved two workshops and two online surveys where participants identified seven general conservation themes and ranked the top five priority issues within each theme. The themes were: (1) policy and management, (2) legislation and enforcement, (3) finance and resource allocation, (4) knowledge, research and development, (5) socio-economic issues, (6) public awareness and participation and (7) rights of nature. In spite of their very different backgrounds and agendas, the four stakeholder groups showed general agreement in their priority preferences except for two issues. Respondents from government and private sector differed the most from each other in their priority choices while academia and NGO showed the highest degree of similarity. This ranked list of 35 conservation priorities is expected to influence the work of policy-makers and others in Peninsular Malaysia and can be used as a model to identify conservation priorities elsewhere

Cabbage and fermented vegetables : From death rate heterogeneity in countries to candidates for mitigation strategies of severe COVID-19

Large differences in COVID-19 death rates exist between countries and between regions of the same country. Some very low death rate countries such as Eastern Asia, Central Europe, or the Balkans have a common feature of eating large quantities of fermented foods. Although biases exist when examining ecological studies, fermented vegetables or cabbage have been associated with low death rates in European countries. SARS-CoV-2 binds to its receptor, the angiotensin-converting enzyme 2 (ACE2). As a result of SARS-CoV-2 binding, ACE2 downregulation enhances the angiotensin II receptor type 1 (AT(1)R) axis associated with oxidative stress. This leads to insulin resistance as well as lung and endothelial damage, two severe outcomes of COVID-19. The nuclear factor (erythroid-derived 2)-like 2 (Nrf2) is the most potent antioxidant in humans and can block in particular the AT(1)R axis. Cabbage contains precursors of sulforaphane, the most active natural activator of Nrf2. Fermented vegetables contain many lactobacilli, which are also potent Nrf2 activators. Three examples are: kimchi in Korea, westernized foods, and the slum paradox. It is proposed that fermented cabbage is a proof-of-concept of dietary manipulations that may enhance Nrf2-associated antioxidant effects, helpful in mitigating COVID-19 severity.Peer reviewe

Nrf2-interacting nutrients and COVID-19 : time for research to develop adaptation strategies

There are large between- and within-country variations in COVID-19 death rates. Some very low death rate settings such as Eastern Asia, Central Europe, the Balkans and Africa have a common feature of eating large quantities of fermented foods whose intake is associated with the activation of the Nrf2 (Nuclear factor (erythroid-derived 2)-like 2) anti-oxidant transcription factor. There are many Nrf2-interacting nutrients (berberine, curcumin, epigallocatechin gallate, genistein, quercetin, resveratrol, sulforaphane) that all act similarly to reduce insulin resistance, endothelial damage, lung injury and cytokine storm. They also act on the same mechanisms (mTOR: Mammalian target of rapamycin, PPAR gamma:Peroxisome proliferator-activated receptor, NF kappa B: Nuclear factor kappa B, ERK: Extracellular signal-regulated kinases and eIF2 alpha:Elongation initiation factor 2 alpha). They may as a result be important in mitigating the severity of COVID-19, acting through the endoplasmic reticulum stress or ACE-Angiotensin-II-AT(1)R axis (AT(1)R) pathway. Many Nrf2-interacting nutrients are also interacting with TRPA1 and/or TRPV1. Interestingly, geographical areas with very low COVID-19 mortality are those with the lowest prevalence of obesity (Sub-Saharan Africa and Asia). It is tempting to propose that Nrf2-interacting foods and nutrients can re-balance insulin resistance and have a significant effect on COVID-19 severity. It is therefore possible that the intake of these foods may restore an optimal natural balance for the Nrf2 pathway and may be of interest in the mitigation of COVID-19 severity

The evolving SARS-CoV-2 epidemic in Africa: Insights from rapidly expanding genomic surveillance

INTRODUCTION Investment in Africa over the past year with regard to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) sequencing has led to a massive increase in the number of sequences, which, to date, exceeds 100,000 sequences generated to track the pandemic on the continent. These sequences have profoundly affected how public health officials in Africa have navigated the COVID-19 pandemic. RATIONALE We demonstrate how the first 100,000 SARS-CoV-2 sequences from Africa have helped monitor the epidemic on the continent, how genomic surveillance expanded over the course of the pandemic, and how we adapted our sequencing methods to deal with an evolving virus. Finally, we also examine how viral lineages have spread across the continent in a phylogeographic framework to gain insights into the underlying temporal and spatial transmission dynamics for several variants of concern (VOCs). RESULTS Our results indicate that the number of countries in Africa that can sequence the virus within their own borders is growing and that this is coupled with a shorter turnaround time from the time of sampling to sequence submission. Ongoing evolution necessitated the continual updating of primer sets, and, as a result, eight primer sets were designed in tandem with viral evolution and used to ensure effective sequencing of the virus. The pandemic unfolded through multiple waves of infection that were each driven by distinct genetic lineages, with B.1-like ancestral strains associated with the first pandemic wave of infections in 2020. Successive waves on the continent were fueled by different VOCs, with Alpha and Beta cocirculating in distinct spatial patterns during the second wave and Delta and Omicron affecting the whole continent during the third and fourth waves, respectively. Phylogeographic reconstruction points toward distinct differences in viral importation and exportation patterns associated with the Alpha, Beta, Delta, and Omicron variants and subvariants, when considering both Africa versus the rest of the world and viral dissemination within the continent. Our epidemiological and phylogenetic inferences therefore underscore the heterogeneous nature of the pandemic on the continent and highlight key insights and challenges, for instance, recognizing the limitations of low testing proportions. We also highlight the early warning capacity that genomic surveillance in Africa has had for the rest of the world with the detection of new lineages and variants, the most recent being the characterization of various Omicron subvariants. CONCLUSION Sustained investment for diagnostics and genomic surveillance in Africa is needed as the virus continues to evolve. This is important not only to help combat SARS-CoV-2 on the continent but also because it can be used as a platform to help address the many emerging and reemerging infectious disease threats in Africa. In particular, capacity building for local sequencing within countries or within the continent should be prioritized because this is generally associated with shorter turnaround times, providing the most benefit to local public health authorities tasked with pandemic response and mitigation and allowing for the fastest reaction to localized outbreaks. These investments are crucial for pandemic preparedness and response and will serve the health of the continent well into the 21st century

A favourable shift towards public acceptance of wildlife conservation in Peninsular Malaysia: comparing the findings of the Wild Life Commission of Malaya (1932) with a recent survey of attitudes in Kuala Lumpur and Taiping, Perak

International audiencePeninsular Malaysia is rich in wildlife including elephants and tigers but local attitudes towards conserving these species varies. With the aim of understanding the factors affecting these attitudes we analysed the data of the 1932 report of the Wild Life Commission of Malaya and compare them with the findings of a 2016 survey carried out in the city of Kuala Lumpur and the town of Taiping, Perak. We identify the limitations of using the full dataset of the Commission and instead focused on the 722 Asian respondents, stratified according to social status, looking at the attitudes of the Asian colonial elite, the kampong elite and farmers; as well as looking at the attitudes of individuals that had engaged in hunting. We compared these results with 525 respondents from the 2016 urban survey and found that the profile of the recent responses is comparable to that of the colonial elite – both being favourable to conservation. We suggest that the dramatic urbanisation and increase in literacy experienced by the peninsula since the 1930s has also seen an overall shift in favour of conservation and we recommend several steps to ensure that the costs of wildlife conservation be shared more equitably