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Background: Dengue is a major public health concern in Reunion Island, marked by recurrent epidemics, including successive outbreaks of dengue virus serotypes 1 and 2 (DENV1 and DENV2) with over 70,000 cases confirmed since 2017. Methodology/Principal findings: In this study, we used Oxford Nanopore NGS technology for sequencing virologically-confirmed samples and clinical isolates collected between 2012 and 2022 to investigate the molecular epidemiology and evolution of DENV in Reunion Island. Here, we generated and analyzed a total of 499 DENV1, 360 DENV2, and 18 DENV3 sequences. By phylogenetic analysis, we show that different genotypes and variants of DENV have circulated in the past decade that likely originated from Seychelles, Mayotte and Southeast Asia and highly affected areas in Asia and Africa. Conclusions/Significance: DENV sequences from Reunion Island exhibit a high genetic diversity which suggests regular introductions of new viral lineages from various Indian Ocean islands. The insights from our phylogenetic analysis may inform local health authorities about the endemicity of DENV variants circulating in Reunion Island and may improve dengue management and surveillance. This work emphasizes the importance of strong local coordination and collaboration to inform public health stakeholders in Reunion Island, neighboring areas, and mainland France. Author summary: This study, conducted from 2012 to 2022, aimed at understanding the dynamics and genetic diversity of dengue virus on Reunion Island, a French overseas department located in the southwestern Indian Ocean, which is regularly affected by dengue epidemics. Several thousand clinical isolates and patient samples were collected from across the island and sequenced, resulting in 877 new genetic sequences of dengue virus. Our results show significant genetic diversity among dengue virus variants that circulated on the island over the past decade. This diversity indicates the simultaneous presence of multiple lineages and closely related viruses, which may have resulted from regular introductions of new variants. Our phylogenetic analyses show that the sequences detected in Reunion Island may have originated from other Indian Ocean islands, such as Seychelles and Mayotte, as well as from Asian regions where dengue virus circulates. [ABSTRACT FROM AUTHOR]

Many journals in ecology and evolutionary biology encourage or require authors to make their data and code available alongside articles. In this study we investigated how often this data and code could be used together, when both were available, to computationally reproduce results published in articles. We surveyed the data and code sharing practices of 177 meta-analyses published in ecology and evolutionary biology journals published between 2015–17: 60% of articles shared data only, 1% shared code only, and 15% shared both data and code. In each of the articles which had shared both (n = 26), we selected a target result and attempted to reproduce it. Using the shared data and code files, we successfully reproduced the targeted results in 27–73% of the 26 articles, depending on the stringency of the criteria applied for a successful reproduction. The results from this sample of meta-analyses in the 2015–17 literature can provide a benchmark for future meta-research studies gauging the computational reproducibility of published research in ecology and evolutionary biology. [ABSTRACT FROM AUTHOR]

Richard Gordon (1921-2017) was a prolific writer of both humorous fiction and historical reviews. He trained in medicine at St Bartholomew's Hospital (Barts) in London and specialised in anaesthesia working at Hill End Hospital, St Albans (where a large proportion of Barts work took place to avoid the impact of the Blitz during the Second World War) and at the Radcliffe Infirmary, Oxford with Robert Macintosh. He published multiple papers and a book on trichlorethylene anaesthesia and edited a textbook of anaesthesia for medical students which ran for 10 editions. His gift for writing and his prominent public persona placed him in a unique position to highlight the importance of the newly emerging speciality of anaesthesia. He did the exact opposite of this and instead created a representation of an uninterested spectator to surgical activity, a representation which still persists in some quarters today. [ABSTRACT FROM AUTHOR]

The Arctic is among the fastest‐warming areas of the globe. Understanding the impact of climate change on foundational Arctic marine species is needed to provide insight on ecological resilience at high latitudes. Marine forests, the underwater seascapes formed by seaweeds, are predicted to expand their ranges further north in the Arctic in a warmer climate. Here, we investigated whether northern habitat gains will compensate for losses at the southern range edge by modelling marine forest distributions according to three distribution categories: cryophilic (species restricted to the Arctic environment), cryotolerant (species with broad environmental preferences inclusive but not limited to the Arctic environment), and cryophobic (species restricted to temperate conditions) marine forests. Using stacked MaxEnt models, we predicted the current extent of suitable habitat for contemporary and future marine forests under Representative Concentration Pathway Scenarios of increasing emissions (2.6, 4.5, 6.0, and 8.5). Our analyses indicate that cryophilic marine forests are already ubiquitous in the north, and thus cannot expand their range under climate change, resulting in an overall loss of habitat due to severe southern range contractions. The extent of marine forests within the Arctic basin, however, is predicted to remain largely stable under climate change with notable exceptions in some areas, particularly in the Canadian Archipelago. Succession may occur where cryophilic and cryotolerant species are extirpated at their southern range edge, resulting in ecosystem shifts towards temperate regimes at mid to high latitudes, though many aspects of these shifts, such as total biomass and depth range, remain to be field validated. Our results provide the first global synthesis of predicted changes to pan‐Arctic coastal marine forest ecosystems under climate change and suggest ecosystem transitions are unavoidable now for some areas. [ABSTRACT FROM AUTHOR]

Background: Patients presenting for thyroidectomy may have an unrecognized pre‐existing vocal cord palsy (VCP). This raises the danger of bilateral VCP if a patient sustains an injury to the RLN on the sole functioning side. Part of the rationale for routine preoperative laryngoscopy is to eliminate such a risk. This paper endeavours to quantify the relevant potential risk. Methods: Patients who underwent laryngoscopy prior to thyroid or parathyroid surgery in an endocrine surgical unit over a 5 year period were identified. Literature review revealed four papers in which VCP prevalence in patients without risk factors was reported. Using our data, combined with that of these other authors, the background rate of pre‐existing VCP was ascertained, and the subsequent risk of bilateral VCP estimated. Results: Of our 632 patients who underwent preoperative laryngoscopy, there were four patients (0.63%) who were found to have a unilateral VCP, but all had voice symptoms or previous neck surgery. When patients with these risk factors are excluded, our data combined with the published data provides a pre‐existing VCP rate of 0.2%. Calculations estimate that if preoperative laryngoscopy is omitted in patients with no risk factors, the risk of bilateral VCP, due to the nerve on the sole functioning side being injured, would be between 1/50000 and 1/150000, depending on an individual surgeon's level of experience. Conclusion: Selective use of laryngoscopy prior to thyroidectomy would result in an acceptably low statistical risk of bilateral VCP. Routine laryngoscopy for all patients is not necessary. [ABSTRACT FROM AUTHOR]

In January 2021, after detection of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) variants, genomic surveillance was established on Réunion Island to track the introduction and spread of SARS-CoV-2 lineages and variants of concern. This system identified 22 SARS-CoV-2 lineages, 71% of which were attributed to the Beta variant. [ABSTRACT FROM AUTHOR]

African savanna elephants (Loxodonta africana) are significant ecosystem engineers – having profound effects on the vegetation when at high population densities. To provide a context for modern conservation decisions it would be useful to know the 'natural' population densities prior to the arrival of firearms in Africa. Here, we use botanical and archaeological arguments to suggest a lower density of elephant populations than in some present protected areas over at least the last few millennia, and arguably much longer. This suggests that elephant population densities seen in some protected areas during the second half of the twentieth century are likely higher than those seen in the past and so have the potential to result in significant negative impacts on associated fauna and flora. [ABSTRACT FROM AUTHOR]

Matrix metalloproteinase‐13 (MMP‐13) is a uniquely important collagenase that promotes the irreversible destruction of cartilage collagen in osteoarthritis (OA). Collagenase activation is a key control point for cartilage breakdown to occur, yet our understanding of the proteinases involved in this process is limited. Neutrophil elastase (NE) is a well‐described proteoglycan‐degrading enzyme which is historically associated with inflammatory arthritis, but more recent evidence suggests a potential role in OA. In this study, we investigated the effect of neutrophil elastase on OA cartilage collagen destruction and collagenase activation. Neutrophil elastase induced significant collagen destruction from human OA cartilage ex vivo, in an MMP‐dependent manner. In vitro, neutrophil elastase directly and robustly activated pro‐MMP‐13, and N‐terminal sequencing identified cleavage close to the cysteine switch at 72MKKPR, ultimately resulting in the fully active form with the neo‐N terminus of 85YNVFP. Mole‐per‐mole, activation was more potent than by MMP‐3, a classical collagenase activator. Elastase was detectable in human OA synovial fluid and OA synovia which displayed histologically graded evidence of synovitis. Bioinformatic analyses demonstrated that, compared with other tissues, control cartilage exhibited remarkably high transcript levels of the major elastase inhibitor, (AAT) alpha‐1 antitrypsin (gene name SERPINA1), but these were reduced in OA. AAT was located predominantly in superficial cartilage zones, and staining enhanced in regions of cartilage damage. Finally, active MMP‐13 specifically inactivated AAT by removal of the serine proteinase cleavage/inhibition site. Taken together, this study identifies elastase as a novel activator of pro‐MMP‐13 that has relevance for cartilage collagen destruction in OA patients with synovitis. [ABSTRACT FROM AUTHOR]

In popular culture, the relationship between science and religion has often been portrayed as one of "conflict." The impact of the conflict thesis can be observed in church leaders' hesitancy in talking about science and religion in the public domain, and it was this finding that inspired the project "Equipping Christian Leadership in an Age of Science." The data presented in this article (collected during 2015–2018) are derived from two separate pieces of research carried out in the United Kingdom. The first consisting of a survey of over 1,000 church leaders and interviews with 20 senior church leaders and, the second, with a strategic focus on ministerial training composed of 12 interviews with church educators. This article reflects on the findings from both pieces of research—covering topics such as church leaders' enthusiasm toward science, how church leaders view the relationship between science and religion and the role of compartmentalization in ministerial training. [ABSTRACT FROM AUTHOR]

Leptospirosis is a zoonotic disease of global importance. The breadth of Leptospira diversity associated with both human and animal disease poses major logistical challenges to the use of classical diagnostic techniques, and increasingly molecular diagnostic tools are used for their detection. In New Zealand, this has resulted in an increase in positive cases reported nationally that have not been attributed to the infecting serovar or genomospecies. In this study, we used data from all pathogenic Leptospira genomes to identify a partial region of the glmU gene as a suitable locus for the discrimination of the infecting species and serovars of New Zealand-endemic Leptospira. This method can be used in culture and culture-independent scenarios making it flexible for diagnostics in humans, animals, and environmental samples. We explored the use of this locus as a molecular barcoding tool via the Oxford Nanopore Technology (ONT) sequencing platform MinION. Sequences obtained by this method allowed specific identification of Leptospira species in mixed and enriched environmental cultures, however read error inherent in the MinION sequencing system reduced the accuracy of strain/variant identification. Using this approach to characterise Leptospira in enriched environmental cultures, we detected the likely presence of Leptospira genomospecies that have not been reported in New Zealand to date. This included a strain of L. borgpetersenii that has recently been identified in dairy cattle and sequences similar to those of L. mayottensis. L. tipperaryensis, L. dzianensis and L. alstonii. [ABSTRACT FROM AUTHOR]

Metalloproteinases were first identified as collagen cleaving enzymes and are now appreciated to play important roles in a wide variety of biological processes. The aberrant activity and dysregulation of the metalloproteinase family are linked to numerous diseases including cardiovascular and pulmonary diseases, chronic wounds, cancer, fibrosis and arthritis. Osteoarthritis (OA) is the most prevalent age-related joint disorder that causes pain and disability, but there are no disease-modifying drugs available. The hallmark of OA is loss of articular cartilage and elevated activities of matrix-degrading metalloproteinases are responsible. These enzymes do not exist in isolation and their activity is tightly regulated by a number of processes, such as transcription, proteolytic activation, interaction with their inhibitors, cell surface and extracellular matrix molecules, and endocytic clearance from the extracellular milieu. Here, we describe the functions and roles of metalloproteinase family in OA pathogenesis. We highlight recent studies that have illustrated novel mechanisms regulating their extracellular activity and impairment of such regulations that lead to the development of OA. We also discuss how to stop or slow down the degenerative processes by targeting aberrant metalloproteinase activity, which may in future become therapeutic interventions for the disease. [ABSTRACT FROM AUTHOR]

During early development, the hindbrain is sub-divided into rhombomeres that underlie the organisation of neurons and adjacent craniofacial tissues. A gene regulatory network of signals and transcription factors establish and pattern segments with a distinct anteroposterior identity. Initially, the borders of segmental gene expression are imprecise, but then become sharply defined, and specialised boundary cells form. In this Review, we summarise key aspects of the conserved regulatory cascade that underlies the formation of hindbrain segments. We describe how the pattern is sharpened and stabilised through the dynamic regulation of cell identity, acting in parallel with cell segregation. Finally, we discuss evidence that boundary cells have roles in local patterning, and act as a site of neurogenesis within the hindbrain. [ABSTRACT FROM AUTHOR]

Summary: A three‐dimensional model was developed for an air‐breathing micro direct methanol fuel cell (μDMFC) with an extended anode catalyst region on the cell channels. The model was evaluated against experimental studies for a μDMFC under several anode distribution conditions, and the results showed a close agreement. The model was employed to study if catalysts coated on the fluid‐flow channel walls could enhance the power generation performance. Further, the effects of the anode catalyst loading of channel walls on the overall cell and individual electrode performances were examined. The modeling results indicated that the fuel cell with anodes both on the proton‐exchange membrane and on channel walls did not show superior performance to the fuel cell with anode catalysts only on the membrane since the overall power generation was mainly limited by the kinetics of the methanol electrode reaction but not the methanol transfer. The modeling results also demonstrated that increasing the anode catalyst loading on channel walls decreased the cathode potential due to an increase in the ohmic loss for the fuel cell with anode catalysts both on the membrane and on channel walls. Reducing channel dimensions decreased the ionic resistance and increased the methanol concentration at the anode and the methanol crossover flux to the cathode. [ABSTRACT FROM AUTHOR]

Serpins (serine proteinase inhibitors) are an ancient superfamily of structurally similar proteins, the majority of which use an elegant suicide inhibition mechanism to target serine proteinases. Despite likely evolving from a single common ancestor, the 36 human serpins have established roles regulating diverse biological processes, such as blood coagulation, embryonic development and extracellular matrix (ECM) turnover. Genetic mutations in serpin genes underpin a host of monogenic disorders -- collectively termed the 'serpinopathies' -- but serpin dysregulation has also been shown to drive pathological mechanisms in many common diseases. Osteoarthritis is a degenerative joint disorder, characterised by the progressive destruction of articular cartilage. This breakdown of the cartilage is driven by the metalloproteinases, and it has long been established that an imbalance of metalloproteinases to their inhibitors is of critical importance. More recently, a role for serine proteinases in cartilage destruction is emerging; including the activation of latent matrix metalloproteinases and cell-surface receptors, or direct proteolysis of the ECM. Serpins likely regulate these processes, as well as having roles beyond serine proteinase inhibition. Indeed, serpins are routinely observed to be highly modulated in osteoarthritic tissues and fluids by 'omic analysis, but despite this, they are largely ignored. Confusing nomenclature and an underappreciation for the role of serine proteinases in osteoarthritis (OA) being the likely causes. In this narrative review, serpin structure, biochemistry and nomenclature are introduced, and for the first time, their putative importance in maintaining joint tissues -- as well as their dysregulation in OA -- are explored. [ABSTRACT FROM AUTHOR]

Vestibular dysfunction is associated with visual short‐term memory impairment; however, it remains unclear if this impairment arises as a direct result of the vestibular dysfunction or is a consequence of comorbid changes in mood, affect, fatigue, and/or sleep. To this end, we assessed the concurrence and interdependence of these comorbidities in 101 individuals recruited from a tertiary balance clinic with a neuro‐otological diagnosis. Over fifty per cent of the sample showed reduced visuospatial short‐term memory, 60% and 37% exceeded cut‐off on the Beck Anxiety and Depression Inventories, respectively, 70% exceeded cut‐off on the Fatigue Severity Scale, 44% reported daytime sleepiness on the Epworth Sleepiness Scale, and 78% scored above cut‐off on the Pittsburgh Sleep Quality Index. The high concurrence of these symptoms gives reason to infer the existence of a vestibular cognitive affective syndrome. Structural equation modelling indicated that the significant statistical association between general unassisted posture (a marker of chronic vestibular dysfunction and strong predictor of falls risk) and short‐term memory was not mediated by mood and wakefulness. Instead, the memory impairment related more directly to vestibular dysfunction. From a rehabilitation perspective, the implication is that if the vestibular disorder is treated successfully then the memory problem will likewise improve. [ABSTRACT FROM AUTHOR]

Introduction: A recent case study showed that repeated sessions of caloric vestibular stimulation (CVS) relieved motor and non-motor symptoms associated with Parkinson's disease (PD). Here we sought to confirm these results in a prospective, double-blind, randomized, placebo treatment-controlled study.Methods: 33 PD subjects receiving stable anti-Parkinsonian therapy completed an active (n = 16) or placebo (n = 17) treatment period. Subjects self-administered CVS at home twice-daily via a portable, pre-programmed, solid-state ThermoNeuroModulation (TNM™) device, which delivered continually-varying thermal waveforms through aluminum ear-probes mounted on a wearable headset. Subjects were followed over a 4-week baseline period, 8 weeks of treatment and then at 5- and 24-weeks post-treatment. At each study visit, standardized clinical assessments were conducted during ON-medication states to evaluate changes in motor and non-motor symptoms, activities of daily living, and quality of life ratings.Results: Change scores between baseline and the end of treatment showed that active-arm subjects demonstrated clinically-relevant reductions in motor and non-motor symptoms that were significantly greater than placebo-arm subjects. Active treatment was also associated with improved scores on activities of daily living assessments. Therapeutic gains were still evident 5 weeks after the end of active treatment but had started to recede at 24 weeks follow-up. No serious adverse events were associated with device use, and there was high participant satisfaction and tolerability of treatment.Conclusion: The results provide evidence that repeated CVS can provide safe and enduring adjuvant relief for motor and non-motor symptoms associated with PD. [ABSTRACT FROM AUTHOR]

The analysis of 87Sr/86Sr isotope ratios in human and nonhuman tooth enamel is used worldwide for archaeological and forensic purposes to establish if an individual is likely to have grown up in the area from which their remains were excavated. The English Peak District has produced an unusually high proportion of archaeological humans who, based on Sr isotope ratios, appear to have come from elsewhere. We have used modern plant samples from the Peak to show that the current understanding of Sr isotope ratios for this area is incomplete – we found many plant samples growing on gritstone sediments had higher Sr values than would be expected based on the current literature. In addition we demonstrated that the taxonomy of the plant does not appear to affect the Sr isotope values (we also found that mycorrhizal type did not determine Sr isotope values in these plants), rather it is the substrate on which it is growing that is important. In terms of human movement, our work suggests it is likely that many archaeological individuals found in the Peak District are indeed local, rather than migrants. It is also possible that the expansion of blanket peat in the Peak has over time reduced the amount of Sr entering the food chain from mineral soils, reducing the radiogenic Sr isotope values in more recent teeth. While our case study is the Peak District, our findings have implications for anomalously high archaeological 87Sr/86Sr isotope values in other upland regions with similar geologies and blanket peats. • Analysis of plant remains in from the Peak District, England identified 87Sr/86Sr isotope values, greater than those expected in the local biosphere. • Neither plant species or mycorrhizal type were related to high Sr isotope ratios, instead plants yielding these values are growing on mineral soils directly overlying gritstones. • These mineral soils have been covered by peat during the Holocene, reducing their availability for grazing and agriculture. This long-term change may indicate why some of the Peak prehistoric sites appear to have high levels of migrants compared to the present day. [ABSTRACT FROM AUTHOR]

Plesiosaurs are an enigmatic, diverse extinct group of Mesozoic marine reptiles well known for their unique body plan with two pairs of flippers and usually an elongated neck. The long neck evolved several times within the clade, yet the evolutionary advantages are not well understood. Previous studies have mainly focused on swimming speeds or flipper locomotion. We evaluated the hydrodynamics of neck length and thickness in plesiosaurs using computational fluid dynamics (CFD) simulations based on the Reynolds-averaged Navier-Stokes (RANS) approach. Simulations were performed of flow patterns forming around five distinctive plesiosaur models, three of different neck lengths (neck/body ratios of 0.2, 0.41, and 0.63) and two of different neck thicknesses (100% and 343% increase compared with cervical vertebrae width). By simulating water flow past the three-dimensional digital plesiosaur models, our results demonstrated that neck elongation does not noticeably affect the force of drag experienced by forward-swimming plesiosaurs. Thicker necks did reduce drag compared with thinner necks, however. The consistent drag coefficient experienced by the three neck lengths used in this study indicates that, at least for forward motion at speeds from 1 to 10 m/s, hydrodynamic implications were not a limiting selective pressure on the evolution of long necks in plesiosaurs. We also tested the effects of bending the long neck during forward motion. Bending a plesiosaur neck evenly in lateral flexion increased the surface area normal to flow and subsequently increased drag force. This effect was most noticeable in the longest-necked forms. [ABSTRACT FROM AUTHOR]

Cartilage destruction is a key characteristic of arthritic disease, a process now widely established to be mediated by metzincins such as MMPs. Despite showing promise in preclinical trials during the 1990s, MMP inhibitors for the blockade of extracellular matrix turnover in the treatment of cancer and arthritis failed clinically, primarily due to poor selectivity for target MMPs. In recent years, roles for serine proteinases in the proteolytic cascades leading to cartilage destruction have become increasingly apparent, renewing interest in the potential for new therapeutic strategies that utilize pharmacological inhibitors against this class of proteinases. Herein, we describe key serine proteinases with likely importance in arthritic disease and highlight recent advances in this field. LINKED ARTICLES: This article is part of a themed section on Translating the Matrix. To view the other articles in this section visit http://onlinelibrary.wiley.com/doi/10.1111/bph.v176.1/issuetoc. [ABSTRACT FROM AUTHOR]

Highlights • We explore a simple quantitative model of selection by survival - the hypothesis that biospheres can acquire persistence-enhancing adaptations by chance over time. • We compare the survival rates of a set of biospheres undergoing selection by survival to a null hypothesis of survival by pure chance, and to biospheres with added feedback from the environment to the biosphere. • We find that selection by survival alone can increase a biosphere's survival probability. • We find that feedback can either hinder or enhance the persistence of a biosphere depending on the strength of the feedback and how closely initial conditions match those ideal for life. Abstract A long-standing objection to the Gaia hypothesis has been a perceived lack of plausible mechanisms by which life on Earth could come to regulate its abiotic environment. A null hypothesis is survival by pure chance, by which any appearance of regulation on Earth is illusory and the persistence of life simply reflects the weak anthropic principle - it must have occurred for intelligent observers to ask the question. Recent work has proposed that persistence alone increases the chance that a biosphere will acquire further persistence-enhancing properties. Here we use a simple quantitative model to show that such 'selection by survival alone' can indeed increase the probability that a biosphere will persist in the future, relative to a baseline of pure chance. Adding environmental feedback to this model shows either an increased or decreased survival probability depending on the initial conditions. Feedback can hinder early life becoming established if initial conditions are poor, but feedback can also prevent systems from diverging too far from optimum environmental conditions and thus increase survival rates. The outstanding question remains the relative importance of each mechanism for the historical and continued persistence of life on Earth. [ABSTRACT FROM AUTHOR]

We report the feasibility of a novel, school-based intervention, coined ‘Imagining Autism’, in which children with autism engage with drama practitioners though participatory play and improvisation in a themed multi-sensory ‘pod’ resembling a portable, tent-like structure. A total of 22 children, aged 7–12 years, from three UK schools engaged in the 10-week programme. Measures of social interaction, communication and emotion recognition, along with parent and teacher ratings, were collected before and up to 12 months after the intervention. Feasibility was evaluated through four domains: (1) process (recruitment, retention, blinding, inter-rater reliability, willingness of children to engage), (2) resources (space, logistics), (3) management (dealing with unexpected changes, ease of assessment) and (4) scientific (data outcomes, statistical analyses). Overall, the children, parents and teachers showed high satisfaction with the intervention, the amount of missing data was relatively low, key assessments were implemented as planned and evidence of potential effect was demonstrated on several key outcome measures. Some difficulties were encountered with recruitment, test administration, parental response and the logistics of setting up the pod. Following several protocol revisions and the inclusion of a control group, future investigation would be justified to more thoroughly examine treatment effects. [ABSTRACT FROM AUTHOR]

One of the most compelling scientific issues of our generation is the Search for Extraterrestrial Intelligence. The question of whether we are alone in the universe has long fascinated the media and the public and has received fresh momentum in the discovery of exoplanets, a small minority of which have Earth like characteristics. The discovery of life elsewhere in the universe, especially if it is intelligent, asks major but fruitful questions of the Christian tradition in areas such as creation, incarnation, redemption and the nature of what it means to be human. Theological work is needed now rather than being left as a future possibility. [ABSTRACT FROM AUTHOR]

Ducks and geese are little studied dispersal vectors for plants lacking a fleshy fruit, and our understanding of the traits associated with these plants is limited. We analyzed 507 faecal samples of mallard (Anas platyrhynchos) and Canada goose (Branta canadensis) from 18 natural and urban wetlands in England, where they are the dominant resident waterfowl. We recovered 930 plant diaspores from 39 taxa representing 18 families, including 28 terrestrial and five aquatic species and four aliens. Mallards had more seeds and seed species per sample than geese, more seeds from barochory and hydrochory syndromes, and seeds that on average were larger and from plants with greater moisture requirements (i.e., more aquatic). Mallards dispersed more plant species than geese in natural habitats. Plant communities and traits dispersed were different between urban (e.g., more achenes) and natural (e.g., more capsules) habitats. Waterfowl can readily spread alien species from urban into natural environments but also allow native terrestrial and aquatic plants to disperse in response to climate heating or other global change. Throughout the temperate regions of the Northern Hemisphere, the mallard is accompanied by a goose (either the Canada goose or the greylag goose) as the most abundant waterfowl in urbanized areas. This combination provides a previously overlooked seed dispersal service for plants with diverse traits. [ABSTRACT FROM AUTHOR]

Photocatalytic water splitting in a novel, UV-irradiated fluidized bed reactor system with Pt-deposited titanium dioxide (TiO 2 ) particles has been explored as an alternative approach to hydrogen production. A model describing the water splitting performance of the fluidized bed system was developed through a holistic approach combining fluidized bed theory, mass transfer effects, an optical model, and a proposed mechanism for the parasitic Pt-catalysed back reaction of H 2 and O 2 . The model was validated experimentally using fluidizable Pt-deposited TiO 2 particles. It was found that the efficiency of the fluidized bed water splitting system is dependent on the rate of mass transfer in the gas–liquid separator, while the overall rate of hydrogen evolution was found to vary with the height and density of the photocatalyst bed in the reactor; all of which are functions of the fluidization flow rate. It is shown that maximizing the rate of mass transfer in the gas–liquid separator can greatly diminish losses due to the Pt-catalysed back reaction of H 2 and O 2 , yielding significant gains in efficiency and the overall rate of hydrogen production. The application of the model to the design of the fluidized bed water splitting system, the sub-systems and the photocatalyst particles is discussed. [ABSTRACT FROM AUTHOR]

The search for habitable exoplanets inspires the question - how do habitable planets form? Planet habitability models traditionally focus on abiotic processes and neglect a biotic response to changing conditions on an inhabited planet. The Gaia hypothesis postulates that life influences the Earth's feedback mechanisms to form a self-regulating system, and hence that life can maintain habitable conditions on its host planet. If life has a strong influence, it will have a role in determining a planet's habitability over time. We present the ExoGaia model - a model of simple 'planets' host to evolving microbial biospheres. Microbes interact with their host planet via consumption and excretion of atmospheric chemicals. Model planets orbit a 'star' that provides incoming radiation, and atmospheric chemicals have either an albedo or a heat-trapping property. Planetary temperatures can therefore be altered by microbes via their metabolisms. We seed multiple model planets with life while their atmospheres are still forming and find that the microbial biospheres are, under suitable conditions, generally able to prevent the host planets from reaching inhospitable temperatures, as would happen on a lifeless planet. We find that the underlying geochemistry plays a strong role in determining long-term habitability prospects of a planet. We find five distinct classes of model planets, including clear examples of 'Gaian bottlenecks' - a phenomenon whereby life either rapidly goes extinct leaving an inhospitable planet or survives indefinitely maintaining planetary habitability. These results suggest that life might play a crucial role in determining the long-term habitability of planets. [ABSTRACT FROM AUTHOR]

The high cost and limited supply of platinum for Pt-based catalysts in proton exchange membrane fuel cells (PEMFCs) have driven intensive research into the use of non-noble metal catalysts in recent years. As the most promising non-noble metal catalysts for PEMFC oxygen reduction reactions (ORR), metal/N/C class of catalysts has been extensively explored. Earlier efforts (1964–2004) were mainly focused on the exploration of various synthesis routes and the investigation of active site mechanisms. During recent years (2005–2010), great progress in the development of these types of non-noble metal catalysts in real PEMFC environments has been achieved both in terms of catalytic activity and stability. From 2011 to present, several new synthetic approaches have been explored to produce highly dense catalytically active sites decorated within micropores using rationally designed zeolite imidazolate frameworks (ZIFs) and porous organic polymers (POPs). Currently, the most active non-noble metal catalysts are derived using this method and are able to deliver a kinetic volumetric current density of 450 A/cm 3 at 0.8 V under fuel cell operating conditions. These results are superior to the US DOE 2020 target of 300 A/cm 3 . In terms of fuel cell maximum power density, the best non-noble metal catalysts for cathodes can achieve results as high as 0.98 W/cm 2 and 0.41 W/cm 2 with feeds of pure O 2 and air respectively. In terms of stability, some non-noble metal catalysts have remained stable for over 1000 h with only minor degradation under PEMFC conditions. Nonetheless, activity and stability still remain major challenges for non-noble metal catalysts when compared to Pt-based ones in PEMFCs. Improvements in the structure of both catalysts and catalyst layers are urgently needed to realize the activity targets established for automobile fuel cell applications as well as the US DOE Hydrogen and Fuel Cell (H&FC) program. In the long term and the sustainable commercialization of fuel cells, replacing Pt-based catalysts with non-noble metal catalysts is, in the present authors' opinion, the most sustainable solution. Therefore, further intensive research into fundamental studies is critical to uncovering the workings of active site mechanisms. Once controllable design and synthesize of non-noble metal catalysts with high active site densities and utilization can be achieved, the goal of cost-effective, non-noble metal catalysts in automobile fuel cells can become reality. [ABSTRACT FROM AUTHOR]

We present a new spectral fitting code, FIREFLY, for deriving the stellar population properties of stellar systems. FIREFLY is a chi-squared minimization fitting code that fits combinations of single-burst stellar population models to spectroscopic data, following an iterative bestfitting process controlled by the Bayesian information criterion. No priors are applied, rather all solutions within a statistical cut are retained with their weight. Moreover, no additive or multiplicative polynomials are employed to adjust the spectral shape. This fitting freedom is envisaged in order to map out the effect of intrinsic spectral energy distribution degeneracies, such as age, metallicity, dust reddening on galaxy properties, and to quantify the effect of varying input model components on such properties. Dust attenuation is included using a new procedure, which was tested on Integral Field Spectroscopic data in a previous paper. The fitting method is extensively tested with a comprehensive suite of mock galaxies, real galaxies from the Sloan Digital Sky Survey and Milky Way globular clusters. We also assess the robustness of the derived properties as a function of signal-to-noise ratio (S/N) and adopted wavelength range. We show that FIREFLY is able to recover age, metallicity, stellar mass, and even the star formation history remarkably well down to an S/N ~ 5, for moderately dusty systems. Code and results are publicly available. [ABSTRACT FROM AUTHOR]

Objective To assess the ability of matriptase, a type II transmembrane serine proteinase, to promote aggrecan loss from the cartilage of patients with osteoarthritis (OA) and to determine whether its inhibition can prevent aggrecan loss and cartilage damage in experimental OA. Methods Aggrecan release from human OA cartilage explants and human stem cell-derived cartilage discs was evaluated, and cartilage-conditioned media were used for Western blotting. Gene expression was analyzed by real-time polymerase chain reaction. Murine OA was induced by surgical destabilization of the medial meniscus, and matriptase inhibitors were administered via osmotic minipump or intraarticular injection. Cartilage damage was scored histologically and aggrecan cleavage was visualized immunohistochemically using specific neoepitope antibodies. Results The addition of soluble recombinant matriptase promoted a time-dependent release of aggrecan (and collagen) from OA cartilage, which was sensitive to metalloproteinase inhibition and protease-activated receptor 2 antagonism. Although engineered human (normal) cartilage discs failed to release aggrecan following matriptase addition, both matrix metalloproteinase- and aggrecanase-mediated cleavages of aggrecan were detected in human OA cartilage. Additionally, while matriptase did not directly degrade aggrecan, it promoted the accumulation of low-density lipoprotein receptor-related protein 1 (LRP-1) in conditioned media of the OA cartilage explants. Matriptase inhibition via neutralizing antibody or small molecule inhibitor significantly reduced cartilage damage scores in murine OA, which was associated with reduced generation of metalloproteinase-mediated aggrecan cleavage. Conclusion Matriptase potently induces the release of metalloproteinase-generated aggrecan fragments as well as soluble LRP-1 from OA cartilage. Therapeutic targeting of matriptase proteolytic activity reduces metalloproteinase activity, further suggesting that this serine proteinase may have potential as a disease-modifying therapy in OA. [ABSTRACT FROM AUTHOR]

Objective To evaluate the safety and efficacy of a novel solid-state, caloric vestibular stimulation (CVS) device to provide adjuvant therapy for the prevention of episodic migraine in adult migraineurs. Background Migraine causes significant disability in ∼12% of the world population. No current migraine preventive treatment provides full clinical relief, and many exhibit high rates of discontinuation due to adverse events. Thus, new therapeutic options are needed. CVS may be an effective and safe adjuvant-therapy for the prevention of episodic migraine. Methods In a multicenter, parallel-arm, block-randomized, placebo-controlled clinical trial (: NCT01899040), subjects completed a 3-month treatment with the TNM™ device for CVS (refer to Fig. 2 for patient enrollment and allocation). The primary endpoint was the change in monthly migraine days from baseline to the third treatment month. Secondary endpoints were 50% responder rates, change in prescription analgesic usage and difference in total subjective headache-related pain scores. Device safety assessments included evaluation of any impact on mood, cognition, or balance. Results Per-protocol, active-arm subjects showed immediate and continued steady declines in migraine frequency over the treatment period. After 3 months of treatment, active-arm subjects exhibited significantly fewer migraine days (−3.9 ± 0.6 from a baseline burden of 7.7 ± 0.5 migraine days). These improvements were significantly greater than those observed in control subjects (−1.1 ± 0.6 from a baseline burden = 6.9 ± 0.7 migraine days) and represented a therapeutic gain of −2.8 migraine days, CI = −0.9 to −4.7, P = .012. Active arm subjects also reported greater reductions in acute medication usage and monthly pain scores compared to controls. No adverse effects on mood, cognition, or balance were reported. Subjects completed the trial with an average rate of 90% treatment adherence. No serious or unexpected adverse events were recorded. The rate of expected adverse events was similar across the active and the placebo groups, and evaluation confirmed that subject blinding remained intact. Conclusion The TNM™ device for CVS appears to provide a clinically efficacious and highly tolerable adjuvant therapy for the prevention of episodic migraine. [ABSTRACT FROM AUTHOR]

We provide observations confirming that viable fragments of bryophytes are dispersed by migratory birds after surviving transit through the alimentary canal. A specimen of Didymodon insulanus was cultured from a large fragment extracted from faeces of Mallard Anas platyrhynchos at Lake Windermere in Cumbria, England. Similar fragments were recorded elsewhere in England in faeces of Mallard and Lapwing Vanellus vanellus. Endozoochory is likely to be an important dispersal mechanism for bryophyte fragments as well as spores. [ABSTRACT FROM AUTHOR]

Objective: To investigate whether caloric vestibular stimulation, a non-invasive form of neuromodulation, alters the level of awareness in people residing in a minimally conscious state. Design: Single-case (n = 2), prospective, controlled (ABAB) efficacy study. Setting: Tertiary, neuro-rehabilitation inpatient ward within a university hospital. Participants: Two individuals in a minimally conscious state. Intervention: Left ear caloric vestibular stimulation was performed in two four/five-week blocks interleaved with two four/five-week blocks of sham stimulation. Session duration and frequency gradually increased within each block from once per day for 10 minutes (Week 1) to once per day for 20 minutes (Week 2) to 20 minutes twice per day in the remaining weeks. Measures: Wessex Head Injury Matrix, JFK Coma Recovery Scale - Revised. Results: Both participants' Wessex Head Injury Matrix scores indicated a transition from involuntary (i.e. mechanical vocalization) to voluntary (i.e. gesture making, selective responses to family members) behaviour that was time-locked to the onset of active stimulation. In one participant, this improvement persisted for at least four weeks after active stimulation, while in the other it diminished two weeks after stimulation. Allied, although less dramatic, changes were seen on the arousal and auditory subscales of the JFK Coma Recovery Scale - Revised. Conclusion: The data provide the first evidence that vestibular stimulation may help improve outcome in a low awareness state, although further studies are needed to replicate effect and determine longer-term benefit. [ABSTRACT FROM AUTHOR]

The Gaia hypothesis postulates that life influences Earth's feedback mechanisms to form a self regulating system. This provokes the question: how can global self-regulation evolve? Most models demonstrating environmental regulation involving life have relied on alignment between local selection and global regulation. In these models environment-improving individuals or communities spread to outcompete environment degrading individuals/communities, leading to global regulation, but this depends on local differences in environmental conditions. In contrast, well-mixed components of the Earth system, such as the atmosphere, lack local environmental differentiation. These previous models do not explain how global regulation can emerge in a system with no well defined local environment, or where the local environment is overwhelmed by global effects. We present a model of self-regulation by ‘microbes’ in an environment with no spatial structure. These microbes affect an abiotic ‘temperature’ as a byproduct of metabolism. We demonstrate that global self-regulation can arise in the absence of spatial structure in a diverse ecosystem without localised environmental effects. We find that systems can exhibit nutrient limitation and two temperature limitation regimes where the temperature is maintained at a near constant value. During temperature regulation, the total temperature change caused by the microbes is kept near constant by the total population expanding or contracting to absorb the impacts of new mutants on the average affect on the temperature per microbe. Dramatic shifts between low temperature regulation and high temperature regulation can occur when a mutant arises that causes the sign of the temperature effect to change. This result implies that self-regulating feedback loops can arise without the need for spatial structure, weakening criticisms of the Gaia hypothesis that state that with just one Earth, global regulation has no mechanism for developing because natural selection requires selection between multiple entities. [ABSTRACT FROM AUTHOR]

Developmental prosopagnosia (DP) is commonly associated with the failure to properly perceive individuating facial properties, notably those conveying configural or holistic content. While this may indicate that the primary impairment is perceptual, it is conceivable that some cases of DP are instead caused by a memory impairment, with any perceptual complaint merely allied rather than causal. To investigate this possibility, we administered a battery of face perception tasks to 11 individuals who reported that their face recognition difficulties disrupt daily activity and who also performed poorly on two formal tests of face recognition. Group statistics identified, relative to age- and gender-matched controls, difficulties in apprehending global–local relations and the holistic properties of faces, and in matching across viewpoints, but these were mild in nature and were not consistently evident at the level of individual participants. Six of the 11 individuals failed to show any evidence of perceptual impairment. In the remaining five individuals, no single perceptual deficit, or combination of deficits, was necessary or sufficient for poor recognition performance. These data suggest that some cases of DP are better explained by a memorial rather than perceptual deficit, and highlight the relevance of the apperceptive/associative distinction more commonly applied to the allied syndrome of acquired prosopagnosia. [ABSTRACT FROM PUBLISHER]

Background: Souvenaid® (uridine monophosphate, docosahexaenoic acid, eicosapentaenoic acid, choline, phospholipids, folic acid, vitamins B12, B6, C, and E, and selenium), was developed to support the formation and function of neuronal membranes.Objective: To determine effect sizes observed in clinical trials of Souvenaid and to calculate the number needed to treat to show benefit or harm.Methods: Data from all three reported randomized controlled trials of Souvenaid in Alzheimer's disease (AD) dementia (Souvenir I, Souvenir II, and S-Connect) and an open-label extension study were included in analyses of effect size for cognitive, functional, and behavioral outcomes. Effect size was determined by calculating Cohen's d statistic (or Cramér's V method for nominal data), number needed to treat and number needed to harm. Statistical calculations were performed for the intent-to-treat populations.Results: In patients with mild AD, effect sizes were 0.21 (95% confidence intervals: -0.06, 0.49) for the primary outcome in Souvenir II (neuropsychological test battery memory z-score) and 0.20 (0.10, 0.34) for the co-primary outcome of Souvenir I (Wechsler memory scale delayed recall). No effect was shown on cognition in patients with mild-to-moderate AD (S-Connect). The number needed to treat (6 and 21 for Souvenir I and II, respectively) and high number needed to harm values indicate a favorable harm:benefit ratio for Souvenaid versus control in patients with mild AD.Conclusions: The favorable safety profile and impact on outcome measures converge to corroborate the putative mode of action and demonstrate that Souvenaid can achieve clinically detectable effects in patients with early AD. [ABSTRACT FROM AUTHOR]

The nucleation, growth and linkage of microvoids are examined in commercially pure magnesium using x-ray computed microtomography (XCT). Tensile testing was performed inside the chamber of an XCT system with each test stopped at various levels of deformation to acquire scans. The nucleation of flat penny-shaped voids is observed relatively early during plastic deformation due to failure at twin and grain boundaries. Once nucleated the voids exhibit rapid growth along preferential directions related to the crystallographic texture of the material as well as the sample geometry. The final fracture occurs by a macroscopic shearing process. Furthermore, the fracture surface reveals two main characteristics: a faceted surface associated with twinning and irregular features related to the failure of grain boundaries. The data exhibit both a quantitative and qualitative difference in the damage development process in magnesium as compared with FCC metals such as aluminum and copper. [ABSTRACT FROM AUTHOR]

In popular discourse today, ‘science’ versus ‘religion’ is a common binary opposition and science and faith are often defined by their assumed opposition to one another. Religious believers are often assumed to be anti-science on the basis of their faith. But how do people of faith actually relate to science? This pilot study addressed this question by focusing on a particular segment of faith communities: senior Christian leaders in England, who have significant influence on values in their organisations as well as in the wider British society. As part of our preliminary data collection we interviewed fourteen leaders, Anglican bishops and directors of other Christian denominations and organisations, exploring how they actually relate to science and conceptualise various science-religion questions. This article considers the implications of science for personal Christian faith. We explore how the interviewees understand the relation between faith and science, how they deal with the difficult questions of evolution and creation and the interpretation of Scripture. We show how the main tension in the conversations about science and faith with Christian leaders is between scientific claims on the one hand, and Christian faith and especially Scripture on the other. A key theme which emerged is an opposition, shared by a majority of the interviewees, against fundamentalism and biblical literalism. We also look at the role of the ‘how/why’ distinction in their approach to science-theology questions (‘science and religion are separate but equal: science answers ‘how’ questions’, religion answers ‘why’ questions.’) We suggest that while many of the senior leaders find this model too simplistic, some may use it as a strategy to avoid the difficult theological and scientific questions in the intersection between science and theology. We conclude that further exploration of these tensions, and research into effective ways to equip Christian leaders to engage with science, is necessary if we want to encourage a deeper, richer science-faith dialogue. [ABSTRACT FROM AUTHOR]

The perception of beat within an auditory rhythm can be facilitated when accompanied by synchronised movements. Electrophysiological investigation shows that this facilitatory effect is associated with a larger P300 amplitude. It has remained unclear, however, which movement-related processes drive this P300 effect. To investigate whether vestibular signals play a role, we administered alternating, sub-sensory (mean=.3 mA) galvanic current to the vestibular nerves of participants while they counted the number of oddballs presented in a stream of tones played at a rate of 1 Hz. Consistent with a vestibular effect, the P300 elicited by the oddballs was increased during stimulation relative to a sham condition, but only when the frequency of the alternating current matched that at which the tones were played. This finding supports the general idea that the vestibular system is involved in audio-motor synchronisation and is the first to show by electrophysiological means that it influences cognitive processes involved in beat perception. [ABSTRACT FROM AUTHOR]

Traditional serological methods, which have been used for decades to evaluate the human erythrocyte antigen (HEA) composition of recipient and donor specimens, have some serious limitations. Specific reagent antisera are not available for all clinically relevant antigens (eg, V antigen). Reagent antisera are expensive, and serological testing is labor intensive. The results of serological testing are subjective and semiquantitative (eg, microscopic, weak, 1+, 2+, 3+, 4+), and may vary from one technologist to another. Further, in many clinical situations, serological testing may be difficult or impossible. laboratory. Most allelic variations occur due to single nucleotide polymorphisms (SNPs), which can be detected and from which the phenotypes can be predicted. HEA genotyping offers several technical and clinical advantages compared with serological testing. The Immucor PreciseType HEA Test is the first and currently the only platform for clinical testing approved by the United States Food and Drug Administration (FDA), to our knowledge. [ABSTRACT FROM AUTHOR]

Island communities are interesting study sites for microbial evolution during epidemics, as their insular nature reduces the complexity of the population's connectivity. This was particularly true on Reunion Island during the first half of 2021, when international travel was restricted in order to mitigate the risk for SARS-CoV-2 introductions. Concurrently, the SARS-CoV-2 Beta variant became dominant and started to circulate at high levels for several months before being completely replaced by the Delta variant as of October 2021. Here, we explore some of the particularities of SARS-CoV-2 genomic evolution within the insular context of Reunion Island. We show that island isolation allowed the amplification and expansion of unique genetic lineages that remained uncommon across the globe. Islands are therefore potential hotspots for the emergence of new genetic variants, meaning that they will play a key role in the continued evolution and propagation of COVID-19 as the pandemic persists. • The epidemiology and evolution of COVID-19 in Reunion Island was unique due to its insular context. • Globally uncommon Beta sublineages were majority variants on the island during much of 2021. • Substitution rates were heterogeneous between SARS-CoV-2 lineages. • Near-complete selective sweeps were the main drivers of COVID epidemiology and evolution. [ABSTRACT FROM AUTHOR]

Purpose: Hypertrophic pyloric stenosis (HPS) is a common condition of infancy, often presenting with marked biochemical derangement, requiring correction. Previous studies have looked at the relationship between serum electrolytes and acid-base balance in HPS but not at the relationship between the degree of biochemical derangement and time taken to resolve the biochemical abnormality.Methods: Retrospective analysis was performed on all 151 infants undergoing pyloromyotomy over a 3 year period. Of these, 105 met the inclusion criteria of: compliance with the unit HPS fluid protocol, and the documentation of at least three serial biochemical investigations. The rate of correction for each biochemical marker (sodium, potassium, chloride, urea, pCO2, hydrogen ion concentration, bicarbonate and the base excess) was plotted against the degree of disturbance and then against time.Results: A significant relationship (P < 0.01) was found between the rate of correction of an abnormal chloride, urea or base excess and the degree of initial derangement. This enables the prediction of the time taken for the required correction of biochemical abnormalities prior to theatre.Conclusion: This method of analysis may be of value in comparing the effectiveness of different fluid regimes in use for the correction of biochemical abnormalities in infants with IHPS. [ABSTRACT FROM AUTHOR]

The role of the microstructure on void growth and linkage in magnesium has been investigated. 2D model materials have been fabricated using pico-second laser technology whereby holes were drilled into the gage section of tensile samples composed of thin Mg sheet. These were pulled in uniaxial tension inside the chamber of an SEM which allowed for a quantitative assessment of the void growth and linkage processes. In contrast to the recent studies of void growth and linkage in fcc metals (copper and aluminum), the local microstructure plays a significant role on the deformation and fracture behavior of magnesium. Void growth was observed to occur non-uniformly due to interactions between the holes and microstructural features such as grain and twin boundaries. In addition, the main fracture mechanisms responsible for void linkage include failure associated with these boundaries. Twin and grain boundaries introduce microstructural features on a length scale comparable to the holes which are not present in models based on continuum mechanics. In order to model the deformation and fracture of magnesium, the initial microstructure as well as microstructural evolution must be taken into account. [ABSTRACT FROM AUTHOR]

The discovery of exoplanets is a small part of the array of scientific arguments for and against the existence of extraterrestrial intelligence. Yet the recent stunning achievement of this program of observational astronomy has had a significant effect on scientific opinion and public interest. It also raises some key theological questions. New observing techniques are leading to the discovery of extrasolar planets daily. Earth-like planets outside of our Solar System can now be identified and in future years explored for signs of life. This article maps the history of these discoveries and highlights some of the theological issues which are important to bring into dialogue with these scientific insights. [ABSTRACT FROM AUTHOR]

A classic question in plant ecology is “why is the world green?” That is, if plants are food for animals why do not animals eat all the available food – changing a ‘green world’ into a ‘brown world’. We first reviewed this question in 2009 and now revisit our arguments in the light of new data and new thinking. Here we argue that (1) the top–down bottom–up dichotomy is probably too simple for understanding a complex system – such as vegetation – rich in feedback processes. (2) Nevertheless it appears that bottom–up processes are generally more important for maintaining the presence of some sort of vegetation while top–down control process are generally more important in determining the type of vegetation at a site. (3) Although this review mainly takes a qualitative and experimental approach to the question, we also argue that simple well-known mathematical models from population ecology can be very informative in thinking about the types of explanations for the green world phenomenon, and demonstrating that it is rarely a simple choice between one form of control or another. [ABSTRACT FROM AUTHOR]

Room temperature fracture during tensile deformation has been studied in two commercial wrought magnesium alloys, namely AZ31B and ZEK100. As a consequence of differences in texture and grain size the deformation modes of these materials differ significantly. This leads to significant differences is the kind of damage that results prior to fracture as evidenced by a combination of traditional metallography and x-ray computed tomography (XCT). The AZ31B samples show little evidence of twinning, in part because of the fine grain size, until after the end of uniform elongation. Moreover, a high r -value, which increases as deformation proceeds, makes this material resistant to shear localization. Damage in this material forms by a combination of ductile dimple formation at second-phase particles and some twin-related microcracking. The ZEK100 samples exhibit extensive twinning and a low r -value (less than 1) meaning that the material is susceptible to shear localization. Although extension twins dominate once the material starts to neck contraction twins are also seen. These form the nucleation sites for an array of penny shaped cracks. In both materials the final fracture is triggered by a macroscopic shear localization that produces a slant fracture surface at 45° to the tensile axis. However, in AZ31B, void linkage produces a fracture surface that is quasi-ductile in appearance, while in ZEK100 the final fracture involves the linkage of the twin-induced microcracks and is quasi-brittle in nature. [ABSTRACT FROM AUTHOR]