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Attitudes about COVID-19 lockdown among general population, France, March 2020
No full textBecause the effectiveness of a coronavirus disease lockdown in curbing coronavirus disease spread depends on public support, acquiring real-time information about the way populations reacted to the lockdown is crucial. In France, such public support remained fragile among low-income persons, probably because the lockdown exacerbated preexisting social inequalities and conflicts
What theories underpin performance-based financing ? A scoping review
No full textPurpose The study aims to explore the theoretical bases justifying the use of performance-based financing (PBF) in the health sector in low- and middle-income countries (LMICs). Design/methodology/approach The authors conducted a scoping review of the literature on PBF so as to identify the theories utilized to underpin it and analyzed its theoretical justifications. Findings Sixty-four studies met the inclusion criteria. Economic theories were predominant, with the principal-agent theory being the most commonly-used theory, explicitly referred to by two-thirds of included studies. Psychological theories were also common, with a wide array of motivation theories. Other disciplines in the form of management or organizational science, political and social science and systems approaches also contributed. However, some of the theories referred to contradicted each other. Many of the studies included only casually alluded to one or more theories, and very few used these theories to justify or support PBF. No theory emerged as a dominant, consistent and credible justification of PBF, perhaps except for the principal-agent theory, which was often inappropriately applied in the included studies, and when it included additional assumptions reflecting the contexts of the health sector in LMICs, might actually warn against adopting PBF. Practical implications Overall, this review has not been able to identify a comprehensive, credible, consistent, theoretical justification for using PBF rather than alternative approaches to health system reforms and healthcare providers' motivation in LMICs. Originality/value The theoretical justifications of PBF in the health sector in LMICs are under-documented. This review is the first of this kind and should encourage further debate and theoretical exploration of the justifications of PBF
New assessment of Anopheles vector species identification using MALDI-TOF MS
No full textBackgroundAnopheles species identification is essential for an effective malaria vector control programme. Matrix-assisted laser desorption ionization-time of flight (MALDI-TOF) mass spectrometry (MS) has been developed to identify adult Anopheles species, using the legs or the cephalothorax. The protein repertoire from arthropods can vary according to compartment, but there is no general consensus regarding the anatomic part to be used.MethodsTo determine the body part of the Anopheles mosquitoes best suited for the identification of field specimens, a mass spectral library was generated with head, thorax with wings and legs of Anopheles gambiae, Anopheles arabiensis and Anopheles funestus obtained from reference centres. The MSL was evaluated using two independent panels of 52 and 40 An. gambiae field-collected in Mali and Guinea, respectively. Geographic variability was also tested using the panel from Mali and several databases containing added specimens from Mali and Senegal.ResultsUsing the head and a database without specimens from the same field collection, the proportion of interpretable and correct identifications was significantly higher than using the other body parts at a threshold value of 1.7 (p<0.0001). The thorax of engorged specimens was negatively impacted by the blood meal after frozen storage. The addition of specimens from Mali into the database significantly improved the results of Mali panel (p<0.0001), which became comparable between head and legs. With higher identification scores, the using of the head will allow to decrease the number of technical replicates of protein extract per specimen, which represents a significant improvement for routine use of MALDI-TOF MS.ConclusionsThe using of the head of Anopheles may improve the performance of MALDI-TOF MS. Region-specific mass spectrum databases will have to be produced. Further research is needed to improve the standardization in order to share online spectral databases
Trends in flow intermittence for European rivers
No full textIntermittent rivers are prevalent in many countries across Europe, but little is known about the temporal evolution of intermittence and its relationship with climate variability. Trend analysis of the annual and seasonal number of zero-flow days, the maximum duration of dry spells and the mean date of the zero-flow events is performed on a database of 452 rivers with varying degrees of intermittence between 1970 and 2010. The relationships between flow intermittence and climate are investigated using the standardized precipitation evapotranspiration index (SPEI) and climate indices describing large-scale atmospheric circulation. The results indicate a strong spatial variability of the seasonal patterns of intermittence and the annual and seasonal number of zero-flow days, highlighting the controls exerted by local catchment properties. Most of the detected trends indicate an increasing number of zero-flow days, which also tend to occur earlier in the year, particularly in southern Europe. The SPEI is found to be strongly related to the annual and seasonal zero-flow day occurrence in more than half of the stations for different accumulation times between 12 and 24 months. Conversely, there is a weaker dependence of river intermittence with large-scale circulation indices. Overall, these results suggest increased water stress in intermittent rivers that may affect their biota and biochemistry and also reduce available water resources
GRAVPSO2D : a Matlab package for 2D gravity inversion in sedimentary basins using the Particle Swarm Optimization algorithm
No full textIn this paper GRAVPSO2D, a Matlab tool for two-dimensional gravity inversion in sedimentary basins using the Particle Swarm Optimization (PSO) algorithm, is presented. The package consists of a collection of functions and scripts that cover the main three parts of the process: (1) the model definition based on the observations, (2) the inversion itself, where the PSO is employed, and (3) the results processing, including best model estimation, uncertainty analysis and plots generation. GRAVPSO2D is freely available, and represents an effort for providing the scientific community with the first tool based on the PSO algorithm in order perform the inversion and the uncertainty assessment of the sedimentary basin gravity inversion problem, taking into account the gravity regional trend estimation, and vertically and horizontally density contrast variations. Synthetic and real examples are provided in order to show the software capabilities
Age matters : dynamics of earthworm casts and burrows produced by the anecic Amynthas khami and their effects on soil water infiltration
No full textBy creating vertical and continuous burrows, anecic earthworms accelerate the transfer of water in soils. However, the degradation mechanisms and lifespan of burrows and the consequence of changes in burrow characteristics for water infiltration remain poorly known. In this study, the dynamics of the degradation and hydraulic properties of burrows made by the anecic earthworm Amynthas khami in a clayey soil were investigated in a meadow and in a woodland in North Vietnam. We selected three categories of surface casts, namely, (i) fresh (a few days old), (ii) dry ( > 1 month old) and (iii) degraded by rain (older than the dry casts), as proxies of the age of burrows. The physical and chemical properties of casts were measured and compared to the surrounding soil aggregates without visible earthworm activity (control). Soil cores were sampled below casts and control and the 3D structure of burrows was characterized using X-ray tomography. Then, water infiltration was measured in the saturated soil cores. Fresh and degraded casts had a lower water stability than control aggregates, whereas higher values were found in dry casts. Water infiltration was twice higher in columns below fresh and dry casts than in the control. However, below degraded casts, the positive effect on water infiltration was reduced or disappeared in some cases. The degradation of burrows led to significant increase in the specific surface area, decrease in their minimum diameter and increase in the abundance of cracks connected to burrows. Our results indicate that anecic burrows persist at least for months below degraded casts but that aging due mainly to physical processes reduces water infiltration. This study highlights the importance of taking into account the lifetime of burrows in the soil when assessing the effect of earthworms on soil structure and water transfer
From formal rules to local practices : a comparative perspective between Algerian and Mexican land reforms
No full textOne of the key issues raised by land policies is the frequent distance between the legal and administrative frameworks as designed by the central power (i.e., formal institutional change), the effective implementation of these policies, and the actual local land practices grounded in the actors' agency. This paper tackles this issue from a comparative perspective regarding land reforms in Algeria and Mexico, drawing on literature reviews, a sound knowledge by the authors of the two countries' land policies, including in a historical perspective, and on the authors' long-term involvement in first-hand field research. Despite historical, social and political differences, the comparison reveals a strikingly convergent picture that allows a certain degree of generalization either in land reform dynamics or in the local practices that emerged after the reforms were implemented. In both cases, the reforms went through successive stages of expropriation and land redistribution, reorganizational structures through which the land was accessed and used, and a specification of beneficiaries' rights emphasizing their collective, non-tradable dimensions. Comparing the situation in Algeria and Mexico sheds light on two fields of practices that reflect the actors' agency while facing heavy government interventions in the local governance of land: a process of de facto decollectivization of agricultural production, and individualization of land rights, and a process of illegal land commoditization, partly through sales, but mainly, through tenancy arrangements. The comparison also illustrates convergences in the form of inadequate public interventions, as well as pragmatic adjustments in administrative practices in order to accommodate for the informal dynamics of individualization and fragmentatio
Intra-host diversity of SARS-Cov-2 should not be neglected : case of the State of Victoria, Australia
No full textSince the identification of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) as the etiological agent of the current COVID-19 pandemic, a rapid and massive effort has been made to obtain the genomic sequences of this virus to monitor (in near real time) the phylodynamic and diversity of this new pathogen. However, less attention has been given to the assessment of intra-host diversity. RNA viruses such as SARS-CoV-2 inhabit the host as a population of variants called quasispecies. We studied the quasispecies diversity in four of the main SARS-CoV-2 genes (ORF1a, ORF1b, S and N genes), using a dataset consisting of 210 next-generation sequencing (NGS) samples collected between January and early April of 2020 in the State of Victoria, Australia. We found evidence of quasispecies diversity in 68% of the samples, 76% of which was nonsynonymous variants with a higher density in the spike (S) glycoprotein and ORF1a genes. About one-third of the nonsynonymous intra-host variants were shared among the samples, suggesting host-to-host transmission. Quasispecies diversity changed over time. Phylogenetic analysis showed that some of the intra-host single-nucleotide variants (iSNVs) were restricted to specific lineages, highlighting their potential importance in the epidemiology of this virus. A greater effort must be made to determine the magnitude of the genetic bottleneck during transmission and the epidemiological and/or evolutionary factors that may play a role in the changes in the diversity of quasispecies over time
Ecosystem maturity modulates greenhouse gases fluxes from artificial lakes
No full textLentic ecosystems play a major role in the global carbon cycling but the understanding of the environmental determinants of lake metabolism is still limited, notably in small artificial lakes. Here the effects of environmental conditions on lake metabolism and CO2 and CH4 emissions were quantified in 11 small artificial gravel pit lakes covering a gradient of ecosystem maturity, ranging from young oligotrophic to older, hypereutrophic lakes. The diffusive fluxes of CO2 and CH4 ranged from -30.10 to 37.78 mmol m(-2) d(-1) and from 3.05 to 25.45 mmol m(-2) d(-1) across gravel pit lakes, respectively. Nutrients and chlorophyll a concentrations were negatively correlated with CO2 concentrations and emissions but positively correlated with CH4 concentrations and emissions from lakes. These findings indicate that, as they mature, gravel pit lakes switch from heterotrophic to autotrophic-based metabolism and hence turn into CO2-sinks. In contrast, the emission of CH4 increased along the maturity gradient. As a result, eutrophication occurring during ecosystem maturity increased net emissions in terms of climate impact (CO2 (equivalent)) due to the higher contribution of CH4 emissions. Overall, mean CO2 (equivalent) emission was 7.9 gm(-2) d(-1), a value 3.7 and 4.7 times higher than values previously reported in temperate lakes and reservoirs, respectively. While previous studies reported that lakes represent emitters of C to the atmosphere, this study highlights that eutrophication may reverse lake contribution to global C budgets. However, this finding is to be balanced with the fact that eutrophication also increased CH4 emissions and hence, enhanced the potential impact of these ecosystems on climate. Implementing mitigation strategies for maintaining intermediate levels of maturity is therefore needed to limit the impacts of small artificial waterbodies on climate. This could be facilitated by their small size and should be planned at the earliest stages of artificial lake construction
Status of the international gravity reference system and frame
No full textThe increasing importance of terrestrial gravimetry in monitoring global change processes, in providing a reference for satellite measurements and in applications in metrology necessitates a stable reference system reflecting the measurement accuracy achievable by modern gravimeters. Therefore, over the last decade, the International Association of Geodesy (IAG) has developed a system to achieve accurate, homogeneous, long-term global recording of Earth's gravity, while taking advantage of the potential of today's absolute gravity measurements. The current status of the International Gravity Reference System and Frame is presented as worked out by the IAG Joint Working Group 2.1.1 "Establishment of a global absolute gravity reference system" during the period 2015-2019. Here, the system is defined by the instantaneous acceleration of free-fall, expressed in the International System of Units (SI) and a set of conventional corrections for the time-independent components of gravity effects. The frame as the systems realization includes a set of conventional temporal gravity corrections which represent a uniform set of minimum requirements. Measurements with absolute gravimeters, the traceability of which is ensured by comparisons and monitoring at reference stations, provide the basis of the frame. A global set of such stations providing absolute gravity values at the microgal level is the backbone of the frame. Core stations with at least one available space geodetic technique will provide a link to the terrestrial reference frame. Expanded facilities enabling instrumental verification as well as repeated regional and additional comparisons will complement key comparisons at the level of the International Committee for Weights and Measures (CIPM) and ensure a common reference and the traceability to the SI. To make the gravity reference system accessible to any user and to replace the previous IGSN71 network, an infrastructure based on absolute gravity observations needs to be built up. This requires the support of national agencies, which are encouraged to establish compatible first order gravity networks and to provide information about existing absolute gravity observations