Does low-dose aspirin initiated before 11 weeks' gestation reduce the rate of preeclampsia?

OBJECTIVE: DATA: Pre-conception or early administration of low-dose aspirin might improve endometrial growth, placental vascularization and organogenesis. Most studies have evaluated the potential benefit of pre-conception or early administration of low-dose aspirin in women with a history of recurrent pregnancy loss, women who have undergone in vitro fertilization or women with thrombophilia or antiphospholipid syndrome. These women are at an increased risk of placenta-associated complications of pregnancy, including preeclampsia, preterm delivery and fetal growth restriction. STUDY: We performed a systematic review and meta-analysis to evaluate the effect of low-dose aspirin initiated at <11 weeks' gestation on the risk of preeclampsia, gestational hypertension, or any hypertensive disorder of pregnancy. Secondary outcomes included preterm delivery at <37 weeks' gestation and fetal growth restriction. STUDY APPRAISAL AND SYNTHESIS METHODS: We searched in MEDLINE via PubMed, EMBASE, Cochrane Central Register of Controlled Trials (CENTRAL), ClinicalTrials.Gov and the World Health Organization International Clinical Trials Registry Platform (WHO-ICTRP) from 1985 to November 2018. Entry criteria were randomized controlled trials evaluating the effect of aspirin administered at 85% of the study population. Relative risks (RR) with 95% confidence intervals (CI) were calculated for each study and pooled for global analysis as the effect measure. We assessed statistical heterogeneity in each meta-analysis using the Chi2 statistics, I2 and Tau2. Heterogeneity was considered substantial if an I2 was greater than 50% and either the Tau2 was greater than zero, or there was a low P-value (<0.10) in the Chi2 test for heterogeneity. Random-effects meta-analysis, weighted by the size of the studies, was performed to produce an overall summary on aspirin effect for each outcome. Sensitivity analysis by sequential omission of each individual study and by fixed-effects model was performed. Publication bias was not assessed due to the small number of included studies. Statistical analysis was performed using Stata release 14.0 (StataCorp, College Station, TX). RESULTS: The entry criteria were fulfilled by eight randomized controlled trials on a combined total of 1,426 participants. Low-dose aspirin initiated at <11 weeks' gestation was associated with a non-significant reduction in the risk of preeclampsia (RR 0.52; 95% CI: 0.23-1.17, P=0.115), gestational hypertension (RR 0.49; 95% CI: 0.20-1.21; P=0.121) and any hypertensive disorder of pregnancy (RR 0.59; 95% CI 0.33-1.04, P=0.067). Early low-dose aspirin reduced the risk of preterm delivery (RR 0.52; 95% CI: 0.27-0.97, p=0.040) but had no impact on the risk of fetal growth restriction (RR 1.10; 95% CI 0.58-2.07, P=0.775). Except for preterm delivery and any hypertensive disorder of pregnancy, sensitivity analysis demonstrated similar observations; therefore confirming the robustness of the analysis. CONCLUSION: The administration of low-dose aspirin at <11 weeks' gestation in high risk women does not decrease the risk of preeclampsia, gestational hypertension, any hypertensive disorder of pregnancy and fetal growth restriction. However, it might reduce the risk of preterm delivery. Larger randomized controlled trials will be required to substantiate the findings.pre-print408 K

Mitochondrial DNA analysis on pre-Columbian bone remains of the Herrera peri

Introducción. Los restos óseos arcaicos son fuente privilegiada de información biológica y su caracterización genética permite confirmar o descartar filiaciones propuestas por otras aproximaciones científicas. La historia precolombina de los Andes orientales se divide en tres periodos principales: i) un poblamiento temprano por parte de grupos cazadores-recolectores; ¡i) un periodo intermedio (Herrera) de pueblos con agricultura incipiente, y iii) un periodo tardío de pueblos chibchas, agrícolas y alfareros (agroalfarero). Objetivo. Analizar el ADN mitocondrial de restos óseos del periodo Herrera. Materiales y métodos. Se analizaron 11 individuos pertenecientes al yacimiento arqueológico Madrid 2-41, con una edad aproximada de 2.000 años. Un fragmento (192 pb) del segmento hipervariable I fue amplificado y secuenciado, siguiendo criterios estrictos de autenticidad de ADN arcaico. Las secuencias se compararon con las existentes en bases de datos de Norteamérica y Europa usando herramientas bioinformáticas. Resultados. Todas las secuencias resultaron idénticas y fueron clasificadas como haplogrupo B. Esto puede relacionarse con el tipo de entierro ritual practicado en Madrid 2-41, es decir, probablemente los individuos analizados hagan parte de una familia jerárquicamente importante en la antigua sociedad Herrera. La búsqueda de secuencias homologas en las bases de datos estadounidense y europea no arrojó coincidencias exactas, aunque existe el reporte de un individuo amazónico de -4.000 años de antigüedad (Brasil) cuya secuencia coincide con la hallada en Madrid 2-41. Conclusión. Los individuos del yacimiento arqueológico Madrid 2-41 están estrechamente emparentados entre sí por línea materna y presentan una secuencia aparentemente ausente en poblaciones actuales.Q4Q3Artículo original569-577Introduction. Ancient bone remains constitute an important source of biological information, and their genetic characterization allows the confirmation or rebuttal of human affiliations proposed on the basis of non-molecular approaches. Pre-Columbian history of the Eastern Andes in Colombia has been divided into three main periods: (i) an early colonization by groups of hunter-gatherers, (ii) an intermediate period “Herrera” characterized by primitive agriculture and (iii) a late stage of Chibcha-speaking groups, with agriculture and ceramics (“agroalfarero”). Objective. The mitochondrial DN A on ancient bone remains of the Herrera period were analyzed for comparison with modern and other ancient DNAs. Materials and methods. Mitochondrial DNA was extracted from 11 Herrera individuals [-2,000 years before present (YBP)] found in the Madrid 2-41 archaeological site near Bogotá, Colombia. A 192 bp segment of the hypervariable segment I was amplified and sequenced, following stringent archaic DNA authenticity criteria. The sequences were compared with those in American and European databases using bioinformatics tools. Results. All individuals had identical sequences and were classified as haplogroup B. This identity may be related to the type of ritual burial performed in the site, probably exclusively for members of a hierarchically important family of the ancient Herrera society. The search for homologous sequences in the American and European mtDNA data bases produced no identical coincidences, although a Brazilian Amazonio individual (-4,000 YBP) was recorded with a matching sequence. Conclusion. Individuals buried in the Madrid 2-41 site were maternally closely related and showed a mtDNA sequence that is apparently absent in contemporary populations

Mitochondrial DNA analysis on pre-Columbian bone remains of the Herrera peri

Introducción. Los restos óseos arcaicos son fuente privilegiada de información biológica y su caracterización genética permite confirmar o descartar filiaciones propuestas por otras aproximaciones científicas. La historia precolombina de los Andes orientales se divide en tres periodos principales: i) un poblamiento temprano por parte de grupos cazadores-recolectores; ¡i) un periodo intermedio (Herrera) de pueblos con agricultura incipiente, y iii) un periodo tardío de pueblos chibchas, agrícolas y alfareros (agroalfarero). Objetivo. Analizar el ADN mitocondrial de restos óseos del periodo Herrera. Materiales y métodos. Se analizaron 11 individuos pertenecientes al yacimiento arqueológico Madrid 2-41, con una edad aproximada de 2.000 años. Un fragmento (192 pb) del segmento hipervariable I fue amplificado y secuenciado, siguiendo criterios estrictos de autenticidad de ADN arcaico. Las secuencias se compararon con las existentes en bases de datos de Norteamérica y Europa usando herramientas bioinformáticas. Resultados. Todas las secuencias resultaron idénticas y fueron clasificadas como haplogrupo B. Esto puede relacionarse con el tipo de entierro ritual practicado en Madrid 2-41, es decir, probablemente los individuos analizados hagan parte de una familia jerárquicamente importante en la antigua sociedad Herrera. La búsqueda de secuencias homologas en las bases de datos estadounidense y europea no arrojó coincidencias exactas, aunque existe el reporte de un individuo amazónico de -4.000 años de antigüedad (Brasil) cuya secuencia coincide con la hallada en Madrid 2-41. Conclusión. Los individuos del yacimiento arqueológico Madrid 2-41 están estrechamente emparentados entre sí por línea materna y presentan una secuencia aparentemente ausente en poblaciones actuales.Q4Q3Artículo original569-577Introduction. Ancient bone remains constitute an important source of biological information, and their genetic characterization allows the confirmation or rebuttal of human affiliations proposed on the basis of non-molecular approaches. Pre-Columbian history of the Eastern Andes in Colombia has been divided into three main periods: (i) an early colonization by groups of hunter-gatherers, (ii) an intermediate period “Herrera” characterized by primitive agriculture and (iii) a late stage of Chibcha-speaking groups, with agriculture and ceramics (“agroalfarero”). Objective. The mitochondrial DN A on ancient bone remains of the Herrera period were analyzed for comparison with modern and other ancient DNAs. Materials and methods. Mitochondrial DNA was extracted from 11 Herrera individuals [-2,000 years before present (YBP)] found in the Madrid 2-41 archaeological site near Bogotá, Colombia. A 192 bp segment of the hypervariable segment I was amplified and sequenced, following stringent archaic DNA authenticity criteria. The sequences were compared with those in American and European databases using bioinformatics tools. Results. All individuals had identical sequences and were classified as haplogroup B. This identity may be related to the type of ritual burial performed in the site, probably exclusively for members of a hierarchically important family of the ancient Herrera society. The search for homologous sequences in the American and European mtDNA data bases produced no identical coincidences, although a Brazilian Amazonio individual (-4,000 YBP) was recorded with a matching sequence. Conclusion. Individuals buried in the Madrid 2-41 site were maternally closely related and showed a mtDNA sequence that is apparently absent in contemporary populations

Healthcare workers hospitalized due to COVID-19 have no higher risk of death than general population. Data from the Spanish SEMI-COVID-19 Registry

Aim To determine whether healthcare workers (HCW) hospitalized in Spain due to COVID-19 have a worse prognosis than non-healthcare workers (NHCW). Methods Observational cohort study based on the SEMI-COVID-19 Registry, a nationwide registry that collects sociodemographic, clinical, laboratory, and treatment data on patients hospitalised with COVID-19 in Spain. Patients aged 20-65 years were selected. A multivariate logistic regression model was performed to identify factors associated with mortality. Results As of 22 May 2020, 4393 patients were included, of whom 419 (9.5%) were HCW. Median (interquartile range) age of HCW was 52 (15) years and 62.4% were women. Prevalence of comorbidities and severe radiological findings upon admission were less frequent in HCW. There were no difference in need of respiratory support and admission to intensive care unit, but occurrence of sepsis and in-hospital mortality was lower in HCW (1.7% vs. 3.9%; p = 0.024 and 0.7% vs. 4.8%; p<0.001 respectively). Age, male sex and comorbidity, were independently associated with higher in-hospital mortality and healthcare working with lower mortality (OR 0.211, 95%CI 0.067-0.667, p = 0.008). 30-days survival was higher in HCW (0.968 vs. 0.851 p<0.001). Conclusions Hospitalized COVID-19 HCW had fewer comorbidities and a better prognosis than NHCW. Our results suggest that professional exposure to COVID-19 in HCW does not carry more clinical severity nor mortality

Consistent patterns of common species across tropical tree communities

Trees structure the Earth’s most biodiverse ecosystem, tropical forests. The vast number of tree species presents a formidable challenge to understanding these forests, including their response to environmental change, as very little is known about most tropical tree species. A focus on the common species may circumvent this challenge. Here we investigate abundance patterns of common tree species using inventory data on 1,003,805 trees with trunk diameters of at least 10 cm across 1,568 locations1,2,3,4,5,6 in closed-canopy, structurally intact old-growth tropical forests in Africa, Amazonia and Southeast Asia. We estimate that 2.2%, 2.2% and 2.3% of species comprise 50% of the tropical trees in these regions, respectively. Extrapolating across all closed-canopy tropical forests, we estimate that just 1,053 species comprise half of Earth’s 800 billion tropical trees with trunk diameters of at least 10 cm. Despite differing biogeographic, climatic and anthropogenic histories7, we find notably consistent patterns of common species and species abundance distributions across the continents. This suggests that fundamental mechanisms of tree community assembly may apply to all tropical forests. Resampling analyses show that the most common species are likely to belong to a manageable list of known species, enabling targeted efforts to understand their ecology. Although they do not detract from the importance of rare species, our results open new opportunities to understand the world’s most diverse forests, including modelling their response to environmental change, by focusing on the common species that constitute the majority of their trees.Publisher PDFPeer reviewe

Performance of non-invasive tests and histology for the prediction of clinical outcomes in patients with non-alcoholic fatty liver disease: an individual participant data meta-analysis

BackgroundHistologically assessed liver fibrosis stage has prognostic significance in patients with non-alcoholic fatty liver disease (NAFLD) and is accepted as a surrogate endpoint in clinical trials for non-cirrhotic NAFLD. Our aim was to compare the prognostic performance of non-invasive tests with liver histology in patients with NAFLD.MethodsThis was an individual participant data meta-analysis of the prognostic performance of histologically assessed fibrosis stage (F0–4), liver stiffness measured by vibration-controlled transient elastography (LSM-VCTE), fibrosis-4 index (FIB-4), and NAFLD fibrosis score (NFS) in patients with NAFLD. The literature was searched for a previously published systematic review on the diagnostic accuracy of imaging and simple non-invasive tests and updated to Jan 12, 2022 for this study. Studies were identified through PubMed/MEDLINE, EMBASE, and CENTRAL, and authors were contacted for individual participant data, including outcome data, with a minimum of 12 months of follow-up. The primary outcome was a composite endpoint of all-cause mortality, hepatocellular carcinoma, liver transplantation, or cirrhosis complications (ie, ascites, variceal bleeding, hepatic encephalopathy, or progression to a MELD score ≥15). We calculated aggregated survival curves for trichotomised groups and compared them using stratified log-rank tests (histology: F0–2 vs F3 vs F4; LSM: 2·67; NFS: 0·676), calculated areas under the time-dependent receiver operating characteristic curves (tAUC), and performed Cox proportional-hazards regression to adjust for confounding. This study was registered with PROSPERO, CRD42022312226.FindingsOf 65 eligible studies, we included data on 2518 patients with biopsy-proven NAFLD from 25 studies (1126 [44·7%] were female, median age was 54 years [IQR 44–63), and 1161 [46·1%] had type 2 diabetes). After a median follow-up of 57 months [IQR 33–91], the composite endpoint was observed in 145 (5·8%) patients. Stratified log-rank tests showed significant differences between the trichotomised patient groups (p<0·0001 for all comparisons). The tAUC at 5 years were 0·72 (95% CI 0·62–0·81) for histology, 0·76 (0·70–0·83) for LSM-VCTE, 0·74 (0·64–0·82) for FIB-4, and 0·70 (0·63–0·80) for NFS. All index tests were significant predictors of the primary outcome after adjustment for confounders in the Cox regression.InterpretationSimple non-invasive tests performed as well as histologically assessed fibrosis in predicting clinical outcomes in patients with NAFLD and could be considered as alternatives to liver biopsy in some cases

The ground stone tools of the Atlantic Mesolithic: a reference assemblage from the coastal dwelling of Beg-er-Vil (Quiberon, Morbihan, France)

Résumé: Les macro-outils sont très peu décrits pour les industries lithiques mésolithiques du territoire français, malgré leur omniprésence dans les habitats. L?habitat côtier de Beg-er-Vil (Quiberon, Morbihan) fouillé entre 2012 et 2018 est une référence particulièrement cohérente d?un point de vue chronologique et stratigraphique pour le septième millénaire avant notre ère. Elle autorise une relecture des autres assemblages lithiques du Mésolithique atlantique, mais également des comparaisons avec les macro-outils du Néolithique récemment étudiés dans la région. Pour un total de 947 objets massifs inventoriés, émerge une série de 130 outils, dont les traces visibles à l?oeil nu ne font aucun doute et 23 outils hypothétiques nécessitant des analyses plus approfondies pour déterminer s?il s?agit de traces d?usage ou non. Neuf types d?outils ont été dégagés, hors fragments, tous divisés en un ou plusieurs sous-types. Le macro-outillage de Beg-er-Vil est très largement dominé par les percuteurs, engagés à l?évidence dans des débitages de matières minérales, mais aussi peut-être dans un concassage de matières dures animales. Suivent en nombre les galets utilisés en pièces intermédiaires très fortement percutées dans un axe longitudinal. Cet article amène à s?interroger sur l?indigence des outils massifs dans le Mésolithique de l?ouest de la France, alors que les ressources minérales adéquates sont particulièrement abondantes sur les estrans. On ne peut plus guère se réfugier derrière de possibles basculement fonctionnels vers d?autres matériaux, puisque les matières animales, bois, os ou coquilles, ne prennent pas le relai, sinon pour fournir des pioches en bois de cerf (à Téviec et Hoedic). Une large comparaison est effectuée avec d?autres zones d?Europe atlantique, à l?évidence mieux pourvues. Les enseignements en termes d?identité technique comme en termes fonctionnels peuvent en être tirés.Abstract: Ground stone tools are rarely described for the mesolithic lithic industries of the French territory, despite their omnipresence in the dwellings. Yet elsewhere in Atlantic Europe, pebble tools sometimes play a major role in defining cultural entities, in Scotland with the Obanian, in northern Spain with the Asturian and in Portugal with the Mirian.This obvious lack of interest in mesolithic macro-tools deprives us of crucial information on technical phylums that are evolving at a different rate from other techniques. What are the standards and practices of use of these tools compared to other material culture ranges? How have they been disseminated in the landscapes through individual or collective mobility practices? What "stylistic territories" do they help us to draw? How can we think of their very slow morphological evolution over time in relation to other tools? Macro-tools thus hold a particular potential for action on matter, different from other tools; discussing their uses or, unlike their non-use, thinking about human engagement with the physical world and seeking a key to understanding their being in the world.The coastal habitat of Beg-er-Vil (Quiberon, Morbihan) excavated between 2012 and 2018 is a particularly coherent reference from a chronological and stratigraphic point of view for the seventh millennium BC. It allows a re-reading of other lithic assemblages of the Atlantic Mesolithic, but also comparisons with the Neolithic ground stone tools recently studied in the region. This coastal position has at least four implications for the availability and use of these tools: 1/ abundance of raw materials on the foreshores, 2/ exploitation of two very different ecosystems (maritime and continental), 3/ very diversified domestic activities on the habitat, 4/ need for tools to dig pits. The distribution of tools on site and the study of structures do not make it possible to highlight specific areas of activity within the habitat.For a total of 947 massive objects inventoried, a series of 130 tools emerged, whose traces visible to the naked eye are beyond doubt and 23 hypothetical tools requiring further analysis to determine whether they have use-wear or not. There are also 470 fragments of pebbles used. The classification of the ground stone tools was based on specific criteria, the first being the type of traces visible on the surfaces, voluntary or involuntary removal, and finally the fragmentation processes in use. Nine types of tools were identified, excluding fragments, all divided into one or more subtypes. The hammers obviously dominate (64%). The intermediate elements are 8% of the entire tools, to which 54 fragments must be added and probably many longitudinally fragment. In all these cases, it should be noted that the stigma of use is relatively undeveloped when compared with equivalent Neolithic tools. There are only four tools more involved than the others: a circular hammer (type A5), two chopping-tools (D2) and a peak (D3). Concerning the types of rocks used, two of them differ considerably from the corpus, quartz for mainly active tools, as well as granite for the largest objects, whether passive or not.This article raises questions about the paucity of ground stone tools in the Mesolithic period in western France, while suitable mineral resources are particularly abundant on foreshores. The lithic assemblages of the Early Mesolithic show a slightly broader register than those of the Late Mesolithic, all things considered. Finally, a broad comparison is made with other areas of Atlantic Europe (France, Spain, Portugal, Scotland), which are obviously better equipped. The paucity of mesolithic macro-tools in Atlantic France reflects a general organization of technical systems that do not use massive tools to interact with the rest of the physical world. It is no longer possible to take refuge behind possible functional shifts to other materials, since animal materials, antlers, bones or shells, do not take over, except to provide deer antler picks (in Téviec and Hoedic).This first classification approach was intended to put a spotlight on a part of the mesolithic technical system that is usually left in the shadows. Our approach was intended to be functional, lato sensu, i.e. the representation of this range of tools can only be judged by integrating all the activities and functions that can be detected in the habitat, by examining combustion structures, cut tools, or organic remains. It is obvious that experimentation is now essential to determine the functions of these tools on central mass, which are not very well transformed.Examining the technical transfers from generation to generation is difficult for the period preceding the Mesolithic. Indeed, there is still very little to say about the Upper and Late Paleolithic of Western France, especially since its maritime declination is currently inaccessible. With regard to the transformations during the Holocene, we thought we saw a possible regression of typological diversity during the Mesolithic period in Atlantic France, but we must remain very cautious due to the lack of sufficient lithic assemblages. It will be much less so if we talk about the real break with the Neolithic from the beginning, whether in the West or more generally in the North of France. New functions and much less collective mobility explain this major contrast in the use of macro-tools, but this break must also be placed in an ontological register.The paucity of mesolithic macro-tools in Atlantic France reflects a general organization of technical systems that do not use massive tools to interact with the rest of the physical world. This absence is a cultural choice; it also reflects a discreet, obviously resilient human imprint, a way of being in the world that shapes subsequent practices

Le macro-outillage en pierre du Mésolithique atlantique : un référentiel bien daté sur l’habitat littoral de Beg-er-Vil (Quiberon, Morbihan)

International audienceGround stone tools are rarely described for the mesolithic lithic industries of the French territory, despite their omnipresence in the dwellings. Yet elsewhere in Atlantic Europe, pebble tools sometimes play a major role in defining cultural entities, in Scotland with the Obanian, in northern Spain with the Asturian and in Portugal with the Mirian.This obvious lack of interest in mesolithic macro-tools deprives us of crucial information on technical phylums that are evolving at a different rate from other techniques. What are the standards and practices of use of these tools compared to other material culture ranges? How have they been disseminated in the landscapes through individual or collective mobility practices? What "stylistic territories" do they help us to draw? How can we think of their very slow morphological evolution over time in relation to other tools? Macro-tools thus hold a particular potential for action on matter, different from other tools; discussing their uses or, unlike their non-use, thinking about human engagement with the physical world and seeking a key to understanding their being in the world.The coastal habitat of Beg-er-Vil (Quiberon, Morbihan) excavated between 2012 and 2018 is a particularly coherent reference from a chronological and stratigraphic point of view for the seventh millennium BC. It allows a re-reading of other lithic assemblages of the Atlantic Mesolithic, but also comparisons with the Neolithic ground stone tools recently studied in the region. This coastal position has at least four implications for the availability and use of these tools: 1/ abundance of raw materials on the foreshores, 2/ exploitation of two very different ecosystems (maritime and continental), 3/ very diversified domestic activities on the habitat, 4/ need for tools to dig pits. The distribution of tools on site and the study of structures do not make it possible to highlight specific areas of activity within the habitat.For a total of 947 massive objects inventoried, a series of 130 tools emerged, whose traces visible to the naked eye are beyond doubt and 23 hypothetical tools requiring further analysis to determine whether they have use-wear or not. There are also 470 fragments of pebbles used. The classification of the ground stone tools was based on specific criteria, the first being the type of traces visible on the surfaces, voluntary or involuntary removal, and finally the fragmentation processes in use. Nine types of tools were identified, excluding fragments, all divided into one or more subtypes. The hammers obviously dominate (64%). The intermediate elements are 8% of the entire tools, to which 54 fragments must be added and probably many longitudinally fragment. In all these cases, it should be noted that the stigma of use is relatively undeveloped when compared with equivalent Neolithic tools. There are only four tools more involved than the others: a circular hammer (type A5), two chopping-tools (D2) and a peak (D3). Concerning the types of rocks used, two of them differ considerably from the corpus, quartz for mainly active tools, as well as granite for the largest objects, whether passive or not.This article raises questions about the paucity of ground stone tools in the Mesolithic period in western France, while suitable mineral resources are particularly abundant on foreshores. The lithic assemblages of the Early Mesolithic show a slightly broader register than those of the Late Mesolithic, all things considered. Finally, a broad comparison is made with other areas of Atlantic Europe (France, Spain, Portugal, Scotland), which are obviously better equipped. The paucity of mesolithic macro-tools in Atlantic France reflects a general organization of technical systems that do not use massive tools to interact with the rest of the physical world. It is no longer possible to take refuge behind possible functional shifts to other materials, since animal materials, antlers, bones or shells, do not take over, except to provide deer antler picks (in Téviec and Hoedic).This first classification approach was intended to put a spotlight on a part of the mesolithic technical system that is usually left in the shadows. Our approach was intended to be functional, lato sensu, i.e. the representation of this range of tools can only be judged by integrating all the activities and functions that can be detected in the habitat, by examining combustion structures, cut tools, or organic remains. It is obvious that experimentation is now essential to determine the functions of these tools on central mass, which are not very well transformed.Examining the technical transfers from generation to generation is difficult for the period preceding the Mesolithic. Indeed, there is still very little to say about the Upper and Late Paleolithic of Western France, especially since its maritime declination is currently inaccessible. With regard to the transformations during the Holocene, we thought we saw a possible regression of typological diversity during the Mesolithic period in Atlantic France, but we must remain very cautious due to the lack of sufficient lithic assemblages. It will be much less so if we talk about the real break with the Neolithic from the beginning, whether in the West or more generally in the North of France. New functions and much less collective mobility explain this major contrast in the use of macro-tools, but this break must also be placed in an ontological register.The paucity of mesolithic macro-tools in Atlantic France reflects a general organization of technical systems that do not use massive tools to interact with the rest of the physical world. This absence is a cultural choice; it also reflects a discreet, obviously resilient human imprint, a way of being in the world that shapes subsequent practices.Les macro-outils sont très peu décrits pour les industries lithiques mésolithiques du territoire français, malgré leur omniprésence dans les habitats. L'habitat côtier de Beg-er-Vil (Quiberon, Morbihan) fouillé entre 2012 et 2018 est une référence particulièrement cohérente d'un point de vue chronologique et stratigraphique pour le septième millénaire avant notre ère. Elle autorise une relecture des autres assemblages lithiques du Mésolithique atlantique, mais également des comparaisons avec les macro-outils du Néolithique récemment étudiés dans la région. Pour un total de 947 objets massifs inventoriés, émerge une série de 130 outils, dont les traces visibles à l'oeil nu ne font aucun doute et 23 outils hypothétiques nécessitant des analyses plus approfondies pour déterminer s'il s'agit de traces d'usage ou non. Neuf types d'outils ont été dégagés, hors fragments, tous divisés en un ou plusieurs sous-types. Le macro-outillage de Beg-er-Vil est très largement dominé par les percuteurs, engagés à l'évidence dans des débitages de matières minérales, mais aussi peut-être dans un concassage de matières dures animales. Suivent en nombre les galets utilisés en pièces intermédiaires très fortement percutées dans un axe longitudinal. Cet article amène à s'interroger sur l'indigence des outils massifs dans le Mésolithique de l'ouest de la France, alors que les ressources minérales adéquates sont particulièrement abondantes sur les estrans. On ne peut plus guère se réfugier derrière de possibles basculement fonctionnels vers d'autres matériaux, puisque les matières animales, bois, os ou coquilles, ne prennent pas le relai, sinon pour fournir des pioches en bois de cerf (à Téviec et Hoedic). Une large comparaison est effectuée avec d'autres zones d'Europe atlantique, à l'évidence mieux pourvues. Les enseignements en termes d'identité technique comme en termes fonctionnels peuvent en être tirés

Análisis espacial de los accidentes de tráfico con víctimas mortales en carretera en España, 2008-2011

Objetivo: Estimar las áreas de mayor densidad de accidentes de tráfico en carretera con víctimas mortales a 24 horas por km2/año en la España peninsular, en el periodo de 2008 a 2011, utilizando un sistema de información geográfica. Métodos: Se geocodificaron los accidentes según la carretera y el punto kilométrico donde ocurrieron. Se calculó el promedio del vecino más cercano para detectar posibles clusters y obtener el ancho de banda necesario para calcular la densidad de Kernel. Resultados: Se analizaron 4775 accidentes, de los cuales el 73,3% se produjeron en carreteras secundarias. La distancia media estimada entre los accidentes fue de 1242 metros, y la distancia media esperada fue de 10.738 metros. El índice del vecino más cercano fue de 0,11, lo que significa que existen agregaciones de accidentes en el espacio. Se obtuvo un mapa con la densidad de Kernel, con una resolución de 1 km2, que permite conocer aquellas áreas donde la densidad es mayor. Conclusiones: Esta metodología permite obtener una mayor aproximación al origen de los riesgos de los accidentes de tráfico al tener en cuenta el punto kilométrico. El mapa obtenido permite visualizar aquellas áreas donde hubo una mayor densidad de accidentes. Esto puede ser una ventaja a la hora de tomar decisiones por parte de las autoridades competentes