Diversité végétale urbaine et estimation du stock de carbone : cas de la commune du Plateau Abidjan, Côte d’Ivoire

La réduction du dioxyde de carbone par les arbres est un important service écosystémique pour le bien-être humain. Dans les milieux urbains, ce processus est souvent négligé ou mal connu. La présente étude, réalisée au Plateau, à Abidjan, a permis d’évaluer la diversité des espèces végétales et le taux de carbone stocké par les arbres. Des jardins, des boulevards ainsi que l’espace de la gare Sud des bus, ont été les sites inventoriés. La présence/absence des espèces végétales ainsi que les circonférences de tous les individus d’arbres de dbh ≥ 10 cm, ont été notées. Au total 91 espèces végétales ont été recensées dont, Milicia regia, endémique et menacée d’extinction, pouvant éveiller la prise de conscience de l’environnement, peut être qualifiée d’emblématique.Dans l’ensemble des espaces, l’équivalent CO2 stocké par individu d’arbre est de 388,9 Kg ; ce qui témoigne du rôle compensatoire des espèces arborescentes, dans les émissions du dioxyde de carbone issu des activités anthropiques. L’ensemble des espaces étudiés, constitue donc un écosystème représentatif de la ville d’Abidjan.Mots-clés : biodiversité urbaine, service écosystémique, bien être humain, Côte d’Ivoire

Efficacy of chest X-rays after drain removal in adult and pediatric patients undergoing cardiac and thoracic surgery: A systematic review.

BACKGROUND: Chest X-rays are routinely obtained after the removal of chest drains in patients undergoing cardiac and thoracic surgical procedures. However, a lack of guidelines and evidence could question the practice. Routine chest X-rays increase exposure to ionizing radiation, increase health-care costs, and lead to overutilisation of available resources. This review aims to explore the evidence in the literature regarding the routine use of chest X-rays following the removal of chest drains. MATERIALS & METHOD: A systematic literature search was conducted in PubMed, Medline via Ovid, Cochrane central register of control trials (CENTRAL), and ClinicalTrials. gov without any limit on the publication year. The references of the included studies are manually screened to identify potentially eligible studies. RESULTS: A total of 375 studies were retrieved through the search and 18 studies were included in the review. Incidence of pneumothorax remains less than 10% across adult cardiac, and pediatric cardiac and thoracic surgical populations. The incidence may be as high as 50% in adult thoracic surgical patients. However, the reintervention rate remains less than 2% across the populations. Development of respiratory and cardiovascular symptoms can adequately guide for a chest X-ray following the drain removal. As an alternative, bedside ultrasound can be used to detect pneumothorax in the thorax after the removal of a chest drain without the need for ionizing radiation. CONCLUSION: A routine chest X-ray following chest drain removal in adult and pediatric patients undergoing cardiac and thoracic surgery is not necessary. It can be omitted without compromising patient safety. Obtaining a chest X-ray should be clinically guided. Alternatively, bedside ultrasound can be used for the same purpose without the need for radiation exposure

Assessing the Risk of Metals and Their Mixtures in the Antarctic Nearshore Marine Environment with Diffusive Gradients in Thin-Films

© 2019 American Chemical Society. Robust environmental assessments and contaminant monitoring in Antarctic near-shore marine environments need new techniques to overcome challenges presented by a highly dynamic environment. This study outlines an approach for contaminant monitoring and risk assessment in Antarctic marine conditions using diffusive gradients in thin-films (DGT) coupled to regionally specific ecotoxicology data and environmental quality standards. This is demonstrated in a field study where DGT samplers were deployed in the near-shore marine environment of East Antarctica around the operational Casey station and the abandoned Wilkes station to measure the time-averaged biologically available fraction of metal contaminants. The incorporation of DGT-labile concentrations to reference toxicity mixture models for three Antarctic organisms predicted low toxic effects (<5% effect to the growth or development of each organism). The comparison of metal concentrations to the Australian and New Zealand default water quality guideline values (WQGVs) showed no marine site exceeding the WQGVs for 95% species protection. However, all sites exceeded the 99% WQGVs due to copper concentrations that are likely of geogenic origin (i.e., not from anthropogenic sources). This study provides evidence supporting the use of the DGT technique to monitor contaminants and assess their environmental risk in the near-shore marine environment of Antarctica

Variational quantum algorithm with information sharing

We introduce an optimisation method for variational quantum algorithms and experimentally demonstrate a 100-fold improvement in efficiency compared to naive implementations. The effectiveness of our approach is shown by obtaining multi-dimensional energy surfaces for small molecules and a spin model. Our method solves related variational problems in parallel by exploiting the global nature of Bayesian optimisation and sharing information between different optimisers. Parallelisation makes our method ideally suited to the next generation of variational problems with many physical degrees of freedom. This addresses a key challenge in scaling-up quantum algorithms towards demonstrating quantum advantage for problems of real-world interest

Exponential Random Graph Modeling for Complex Brain Networks

Exponential random graph models (ERGMs), also known as p* models, have been utilized extensively in the social science literature to study complex networks and how their global structure depends on underlying structural components. However, the literature on their use in biological networks (especially brain networks) has remained sparse. Descriptive models based on a specific feature of the graph (clustering coefficient, degree distribution, etc.) have dominated connectivity research in neuroscience. Corresponding generative models have been developed to reproduce one of these features. However, the complexity inherent in whole-brain network data necessitates the development and use of tools that allow the systematic exploration of several features simultaneously and how they interact to form the global network architecture. ERGMs provide a statistically principled approach to the assessment of how a set of interacting local brain network features gives rise to the global structure. We illustrate the utility of ERGMs for modeling, analyzing, and simulating complex whole-brain networks with network data from normal subjects. We also provide a foundation for the selection of important local features through the implementation and assessment of three selection approaches: a traditional p-value based backward selection approach, an information criterion approach (AIC), and a graphical goodness of fit (GOF) approach. The graphical GOF approach serves as the best method given the scientific interest in being able to capture and reproduce the structure of fitted brain networks

Alpha-band rhythms in visual task performance: phase-locking by rhythmic sensory stimulation

Oscillations are an important aspect of neuronal activity. Interestingly, oscillatory patterns are also observed in behaviour, such as in visual performance measures after the presentation of a brief sensory event in the visual or another modality. These oscillations in visual performance cycle at the typical frequencies of brain rhythms, suggesting that perception may be closely linked to brain oscillations. We here investigated this link for a prominent rhythm of the visual system (the alpha-rhythm, 8-12 Hz) by applying rhythmic visual stimulation at alpha-frequency (10.6 Hz), known to lead to a resonance response in visual areas, and testing its effects on subsequent visual target discrimination. Our data show that rhythmic visual stimulation at 10.6 Hz: 1) has specific behavioral consequences, relative to stimulation at control frequencies (3.9 Hz, 7.1 Hz, 14.2 Hz), and 2) leads to alpha-band oscillations in visual performance measures, that 3) correlate in precise frequency across individuals with resting alpha-rhythms recorded over parieto-occipital areas. The most parsimonious explanation for these three findings is entrainment (phase-locking) of ongoing perceptually relevant alpha-band brain oscillations by rhythmic sensory events. These findings are in line with occipital alpha-oscillations underlying periodicity in visual performance, and suggest that rhythmic stimulation at frequencies of intrinsic brain-rhythms can be used to reveal influences of these rhythms on task performance to study their functional roles

TSPO interacts with VDAC1 and triggers a ROS-mediated inhibition of mitochondrial quality control

The 18-kDa TSPO (translocator protein) localizes on the outer mitochondrial membrane (OMM) and participates in cholesterol transport. Here, we report that TSPO inhibits mitochondrial autophagy downstream of the PINK1-PARK2 pathway, preventing essential ubiquitination of proteins. TSPO abolishes mitochondrial relocation of SQSTM1/p62 (sequestosome 1), and consequently that of the autophagic marker LC3 (microtubule-associated protein 1 light chain 3), thus leading to an accumulation of dysfunctional mitochondria, altering the appearance of the network. Independent of cholesterol regulation, the modulation of mitophagy by TSPO is instead dependent on VDAC1 (voltage-dependent anion channel 1), to which TSPO binds, reducing mitochondrial coupling and promoting an overproduction of reactive oxygen species (ROS) that counteracts PARK2-mediated ubiquitination of proteins. These data identify TSPO as a novel element in the regulation of mitochondrial quality control by autophagy, and demonstrate the importance for cell homeostasis of its expression ratio with VDAC1

The implementation of remote home monitoring models during the COVID-19 pandemic in England.

BACKGROUND: There is a paucity of evidence for the implementation of remote home monitoring for COVID-19 infection. The aims of this study were to identify the key characteristics of remote home monitoring models for COVID-19 infection, explore the experiences of staff implementing these models, understand the use of data for monitoring progress against outcomes, and document variability in staffing and resource allocation. METHODS: This was a multi-site mixed methods study conducted between July and August 2020 that combined qualitative and quantitative approaches to analyse the implementation and impact of remote home monitoring models developed during the first wave of the COVID-19 pandemic in England. The study combined interviews (n = 22) with staff delivering these models across eight sites in England with the collection and analysis of data on staffing models and resource allocation. FINDINGS: The models varied in relation to the healthcare settings and mechanisms used for patient triage, monitoring and escalation. Implementation was embedded in existing staff workloads and budgets. Good communication within clinical teams, culturally-appropriate information for patients/carers and the combination of multiple approaches for patient monitoring (app and paper-based) were considered facilitators in implementation. The mean cost per monitored patient varied from £400 to £553, depending on the model. INTERPRETATION: It is necessary to provide the means for evaluating the effectiveness of these models, for example, by establishing comparator data. Future research should also focus on the sustainability of the models and patient experience (considering the extent to which some of the models exacerbate existing inequalities in access to care)