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In Fig. 2 of this Article, the positive part of the y axis scale should read 0, 0.02, 0.04 instead of 0, 0.04, 0.02. This has been corrected online.
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With excellent energy resolution and ultralow-level radiogenic backgrounds, the high-purity germanium detectors in the Majorana Demonstrator enable searches for several classes of exotic dark matter (DM) models. In this work, we report new experimental limits on keV-scale sterile neutrino DM via the transition magnetic moment from conversion to active neutrinos ν_{s}âν_{a}. We report new limits on fermionic dark matter absorption (χ+Aâν+A) and sub-GeV DM-nucleus 3â2 scattering (χ+χ+AâÏ+A), and new exclusion limits for bosonic dark matter (axionlike particles and dark photons). These searches utilize the (1-100)-keV low-energy region of a 37.5-kg y exposure collected by the Demonstrator between May 2016 and November 2019 using a set of ^{76}Ge-enriched detectors whose surface exposure time was carefully controlled, resulting in extremely low levels of cosmogenic activation.
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Global warming is forcing many species to shift their distributions upward, causing consequent changes in the compositions of species that occur at specific locations. This prediction remains largely untested for tropical trees. Here we show, using a database of nearly 200 Andean forest plot inventories spread across more than 33.5° latitude (from 26.8° S to 7.1° N) and 3,000-m elevation (from 360 to 3,360 m above sea level), that tropical and subtropical tree communities are experiencing directional shifts in composition towards having greater relative abundances of species from lower, warmer elevations. Although this phenomenon of 'thermophilization' is widespread throughout the Andes, the rates of compositional change are not uniform across elevations. The observed heterogeneity in thermophilization rates is probably because of different warming rates and/or the presence of specialized tree communities at ecotones (that is, at the transitions between distinct habitats, such as at the timberline or at the base of the cloud forest). Understanding the factors that determine the directions and rates of compositional changes will enable us to better predict, and potentially mitigate, the effects of climate change on tropical forests.
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Aclimatação , Altitude , Biodiversidade , Florestas , Aquecimento Global , Temperatura , Árvores/classificação , Árvores/fisiologia , Bases de Dados Factuais , Planejamento em Desastres/tendências , Desastres/prevenção & controle , Previsões/métodos , Especificidade da Espécie , Clima TropicalRESUMO
This corrects the article DOI: 10.1103/PhysRevLett.129.080401.
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^{180m}Ta is a rare nuclear isomer whose decay has never been observed. Its remarkably long lifetime surpasses the half-lives of all other known ß and electron capture decays due to the large K-spin differences and small energy differences between the isomeric and lower-energy states. Detecting its decay presents a significant experimental challenge but could shed light on neutrino-induced nucleosynthesis mechanisms, the nature of dark matter, and K-spin violation. For this study, we repurposed the Majorana Demonstrator, an experimental search for the neutrinoless double-beta decay of ^{76}Ge using an array of high-purity germanium detectors, to search for the decay of ^{180m}Ta. More than 17 kg, the largest amount of tantalum metal ever used for such a search, was installed within the ultralow-background detector array. In this Letter, we present results from the first year of Ta data taking and provide an updated limit for the ^{180m}Ta half-life on the different decay channels. With new limits up to 1.5×10^{19} yr, we improved existing limits by 1-2 orders of magnitude which are the most sensitive searches for a single ß and electron capture decay ever achieved. Over all channels, the decay can be excluded for T_{1/2}<0.29×10^{18} yr.
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The Majorana Demonstrator searched for neutrinoless double-ß decay (0νßß) of ^{76}Ge using modular arrays of high-purity Ge detectors operated in vacuum cryostats in a low-background shield. The arrays operated with up to 40.4 kg of detectors (27.2 kg enriched to â¼88% in ^{76}Ge). From these measurements, the Demonstrator has accumulated 64.5 kg yr of enriched active exposure. With a world-leading energy resolution of 2.52 keV FWHM at the 2039 keV Q_{ßß} (0.12%), we set a half-life limit of 0νßß in ^{76}Ge at T_{1/2}>8.3×10^{25} yr (90% C.L.). This provides a range of upper limits on m_{ßß} of (113-269) meV (90% C.L.), depending on the choice of nuclear matrix elements.
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The Majorana Demonstrator neutrinoless double-beta decay experiment comprises a 44 kg (30 kg enriched in ^{76}Ge) array of p-type, point-contact germanium detectors. With its unprecedented energy resolution and ultralow backgrounds, Majorana also searches for rare event signatures from beyond standard model physics in the low energy region below 100 keV. In this Letter, we test the continuous spontaneous localization (CSL) model, one of the mathematically well-motivated wave function collapse models aimed at solving the long-standing unresolved quantum mechanical measurement problem. While the CSL predicts the existence of a detectable radiation signature in the x-ray domain, we find no evidence of such radiation in the 19-100 keV range in a 37.5 kg-y enriched germanium exposure collected between December 31, 2015, and November 27, 2019, with the Demonstrator. We explored both the non-mass-proportional (n-m-p) and the mass-proportional (m-p) versions of the CSL with two different assumptions: that only the quasifree electrons can emit the x-ray radiation and that the nucleus can coherently emit an amplified radiation. In all cases, we set the most stringent upper limit to date for the white CSL model on the collapse rate, λ, providing a factor of 40-100 improvement in sensitivity over comparable searches. Our limit is the most stringent for large parts of the allowed parameter space. If the result is interpreted in terms of the Diòsi-Penrose gravitational wave function collapse model, the lower bound with a 95% confidence level is almost an order of magnitude improvement over the previous best limit.
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Axions were originally proposed to explain the strong-CP problem in QCD. Through axion-photon coupling, the Sun could be a major source of axions, which could be measured in solid state detection experiments with enhancements due to coherent Primakoff-Bragg scattering. The Majorana Demonstrator experiment has searched for solar axions with a set of ^{76}Ge-enriched high purity germanium detectors using a 33 kg-yr exposure collected between January, 2017 and November, 2019. A temporal-energy analysis gives a new limit on the axion-photon coupling as g_{aγ}<1.45×10^{-9} GeV^{-1} (95% confidence level) for axions with mass up to 100 eV/c^{2}. This improves laboratory-based limits between about 1 eV/c^{2} and 100 eV/c^{2}.
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Most ß-thalassemias are caused by mutations involving one or a limited number of nucleotides within the gene or its adjacent regions. They can be substitutions or deletions; in these cases, the loss ranges from a single nucleotide to even the entire HBB gene, so we wonder if the phenotype is due to the size of the deletion or the location of the mutation. To clarify this, we present two new deletions in the ß-globin gene that cause ß0-thalassemia. The hematological parameters were determined with an automated cell counter; the Hb A2 and Hb F levels were measured by performance liquid chromatography. Hemoglobins were analyzed by capillary zone electrophoresis (Sebia Capillarys Flex system) and ion-exchange HPLC (BioRad Variant II ß-thalassemia Short Program). Molecular characterization was performed by automatic Sanger sequencing. The screening of common α-thalassemia point mutations and deletions in the world (21 in total) were carried out using multiplex PCR followed by reverse-hybridization with a commercial Alpha-Globin StripAssay kit. We have characterized two new mutations-(1) 1-bp deletion [CD61/62(-G)] [HBB:c.186_187delG], (2) 105-bp deletion [IVS-2-nt767-CD111] [HBB:c.316-84_333del]-and we have described, for first time in Spain, the 25-bp deletion [ß nts 252 - 276 deleted] [HBB:c.93-22_95del] mutation. These mutations were classified as pathogenic by UniProt Variants confirmed according to the American College of Medical Genetics and Genomics guidelines. These mutations present a phenotype compatible with ß0-thalassemia, supported by hematological parameters that correlate the degree of reduction in the synthesis of the ß-globin chain. Identification of this type of mutation is important for genetic counselling of partners where both are carriers, so that they are aware of the genetic risk of having affected children, allowing them to take an informed decision about their reproductive choices.
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Talassemia alfa , Talassemia beta , Genótipo , Hemoglobina A2/genética , Hemoglobinas/genética , Humanos , Mutação , alfa-Globinas/genética , Talassemia alfa/genética , Globinas beta/genética , Talassemia beta/diagnóstico , Talassemia beta/genéticaRESUMO
SARS-CoV-2 mainly affects the respiratory system, but the gastrointestinal tract is also a target. Prolonged gut disorders, in COVID-19 patients, were correlated with decreased richness and diversity of the gut microbiota, immune deregulation and delayed viral clearance. Although there are no definitive conclusions, ample evidence would suggest that the gut microbiome composition and function play a role in COVID-19 progression. Microbiome modulation strategies for population stratification and management of COVID-19 infection are under investigation, representing an area of interest in the ongoing pandemic. In this review, we present the existing data related to the interaction between gut microbes and the host's immune response to SARS-CoV-2 and discuss the implications for current disease management and readiness to face future pandemics.
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The COVID-19 pandemic has led to the admission of a high number of patients to the ICU, generally due to severe respiratory failure. Since the appearance of the first cases of SARS-CoV-2 infection, at the end of 2019, in China, a huge number of treatment recommendations for this entity have been published, not always supported by sufficient scientific evidence or with methodological rigor necessary. Thanks to the efforts of different groups of researchers, we currently have the results of clinical trials, and other types of studies, of higher quality. We consider it necessary to create a document that includes recommendations that collect this evidence regarding the diagnosis and treatment of COVID-19, but also aspects that other guidelines have not considered and that we consider essential in the management of critical patients with COVID-19. For this, a drafting committee has been created, made up of members of the SEMICYUC Working Groups more directly related to different specific aspects of the management of these patients.
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An increasing healthcare challenge in the management of haematological malignancy (HM) is secondary immunodeficiency. From January 2019, the EMA included the evaluation of specific antibody (Ab) responses to better select patients for immunoglobulin replacement therapy (IgRT). We evaluated Ab responses to pneumococcal and Salmonella typhi pure polysaccharide immunization in a cohort of 42 HM patients and 24 healthy-controls. Pre-post specific Ab concentrations were measured by ELISA at 4â¯weeks. Globally, significantly lower Typhim Vi (TV) seroprevalence (9%) compared to 23-valent pneumococcal polysaccharide vaccine (PPV) (76%) (pâ¯<0.001) was observed. TV non responders (88%) were higher than PPV non responders (62%) (pâ¯<0.0001) and correlated better to infectious history. By ROC analysis, pre-post 5-fold TV increase was the best cut-off to discriminate HM with recurrent infections and controls (sensitivity 91%, specificity 100%). Despite the small sample cohort, our results suggest that specific anti-S typhi Ab response is a useful complementary assay in the diagnosis and management decision of SID to HM.
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Neoplasias Hematológicas/diagnóstico , Síndromes de Imunodeficiência/diagnóstico , Polissacarídeos Bacterianos/imunologia , Salmonella typhi/fisiologia , Febre Tifoide/imunologia , Vacinas Tíficas-Paratíficas/imunologia , Adulto , Idoso , Anticorpos Antibacterianos/sangue , Formação de Anticorpos , Estudos de Coortes , Feminino , Neoplasias Hematológicas/epidemiologia , Neoplasias Hematológicas/imunologia , Humanos , Síndromes de Imunodeficiência/epidemiologia , Síndromes de Imunodeficiência/imunologia , Masculino , Pessoa de Meia-Idade , Prognóstico , Estudos Retrospectivos , Estudos Soroepidemiológicos , Espanha/epidemiologiaRESUMO
ANAIS is a direct detection dark matter experiment aiming at the testing of the DAMA/LIBRA annual modulation result, which, for about two decades, has neither been confirmed nor ruled out by any other experiment in a model independent way. ANAIS-112, consisting of 112.5 kg of sodium iodide crystals, has been taking data at the Canfranc Underground Laboratory, Spain, since August 2017. This Letter presents the annual modulation analysis of 1.5 years of data, amounting to 157.55 kg yr. We focus on the model independent analysis searching for modulation and the validation of our sensitivity prospects. ANAIS-112 data are consistent with the null hypothesis (p values of 0.67 and 0.18 for [2-6] and [1-6] keV energy regions, respectively). The best fits for the modulation hypothesis are consistent with the absence of modulation (S_{m}=-0.0044±0.0058 cpd/kg/keV and -0.0015±0.0063 cpd/kg/keV, respectively). They are in agreement with our estimated sensitivity for the accumulated exposure, which supports our projected goal of reaching a 3σ sensitivity to the DAMA/LIBRA result in five years of data taking.
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The Majorana Demonstrator is an ultralow-background experiment searching for neutrinoless double-beta decay in ^{76}Ge. The heavily shielded array of germanium detectors, placed nearly a mile underground at the Sanford Underground Research Facility in Lead, South Dakota, also allows searches for new exotic physics. Free, relativistic, lightly ionizing particles with an electrical charge less than e are forbidden by the standard model but predicted by some of its extensions. If such particles exist, they might be detected in the Majorana Demonstrator by searching for multiple-detector events with individual-detector energy depositions down to 1 keV. This search is background-free, and no candidate events have been found in 285 days of data taking. New direct-detection limits are set for the flux of lightly ionizing particles for charges as low as e/1000.
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The Majorana Collaboration is operating an array of high purity Ge detectors to search for neutrinoless double-ß decay in ^{76}Ge. The Majorana Demonstrator comprises 44.1 kg of Ge detectors (29.7 kg enriched in ^{76}Ge) split between two modules contained in a low background shield at the Sanford Underground Research Facility in Lead, South Dakota. Here we present results from data taken during construction, commissioning, and the start of full operations. We achieve unprecedented energy resolution of 2.5 keV FWHM at Q_{ßß} and a very low background with no observed candidate events in 9.95 kg yr of enriched Ge exposure, resulting in a lower limit on the half-life of 1.9×10^{25} yr (90% C.L.). This result constrains the effective Majorana neutrino mass to below 240-520 meV, depending on the matrix elements used. In our experimental configuration with the lowest background, the background is 4.0_{-2.5}^{+3.1} counts/(FWHM t yr).
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We present new limits on exotic keV-scale physics based on 478 kg d of Majorana Demonstrator commissioning data. Constraints at the 90% confidence level are derived on bosonic dark matter (DM) and solar axion couplings, Pauli exclusion principle violating (PEPV) decay, and electron decay using monoenergetic peak signal limits above our background. Our most stringent DM constraints are set for 11.8 keV mass particles, limiting g_{Ae}<4.5×10^{-13} for pseudoscalars and (α^{'}/α)<9.7×10^{-28} for vectors. We also report a 14.4 keV solar axion coupling limit of g_{AN}^{eff}×g_{Ae}<3.8×10^{-17}, a 1/2ß^{2}<8.5×10^{-48} limit on the strength of PEPV electron transitions, and a lower limit on the electron lifetime of τ_{e}>1.2×10^{24} yr for e^{-}â invisible.
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OBJECTIVE: To determine the relationship of interpregnancy interval with maternal and offspring outcomes. DESIGN: Retrospective study with data from the Perinatal Information System database of the Latin American Centre for Perinatology and Human Development, Uruguay. SETTING: Latin America, 1990-2009. POPULATION: A cohort of 894 476 women delivering singleton infants. METHODS: During 1990-2009 the Perinatal Information System database of the Latin American Centre for Perinatology identified 894 476 women with defined interpregnancy intervals: i.e. the time elapsed between the date of the previous delivery and the first day of the last normal menstrual period for the index pregnancy. Using the interval 12-23 months as the reference category, multiple logistic regression estimated adjusted odds ratios (aORs) with 95% confidence intervals (95% CIs) of the association between various interval lengths and maternal and offspring outcomes. MAIN OUTCOME MEASURES: Maternal death, pre-eclampsia, eclampsia, puerperal infection, fetal death, neonatal death, preterm birth, and low birthweight. RESULTS: In the reference interval there was 0.05% maternal death, 1.00% postpartum haemorrhage, 2.80% pre-eclampsia, 0.15% eclampsia, 0.28% puerperal infection, 3.45% fetal death, 0.68% neonatal death, 12.33% preterm birth, and 9.73% low birthweight. Longer intervals had increased odds of pre-eclampsia (>72 months), fetal death (>108-119 months), and low birthweight (96-107 months). Short intervals of <12 months had increased odds of pre-eclampsia (aOR 0.80; 95% CI 0.76-0.85), neonatal death (aOR 1.18; 95% CI 1.08-1.28), and preterm birth (aOR 1.16; 95% CI 1.11-1.21). Statistically, the interval had no relationship with maternal death, eclampsia, and puerperal infection. CONCLUSIONS: A short interpregnancy interval of <12 months is associated with pre-eclampsia, neonatal mortality, and preterm birth, but not with other maternal or offspring outcomes. Longer intervals of >72 months are associated with pre-eclampsia, fetal death, and low birthweight, but not with other maternal or offspring outcomes. TWEETABLE ABSTRACT: A short interpregnancy interval of <12 months is associated with neonatal mortality and preterm birth.
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Intervalo entre Nascimentos , Mortalidade Infantil , Recém-Nascido de Baixo Peso , Complicações na Gravidez/etiologia , Feminino , Humanos , Lactente , Recém-Nascido , América Latina/epidemiologia , Modelos Logísticos , Estudos Longitudinais , Razão de Chances , Paridade , Gravidez , Complicações na Gravidez/epidemiologia , Resultado da Gravidez , Estudos Retrospectivos , Fatores de Risco , Fatores de TempoRESUMO
OBJECTIVE: To generate a global reference for caesarean section (CS) rates at health facilities. DESIGN: Cross-sectional study. SETTING: Health facilities from 43 countries. POPULATION/SAMPLE: Thirty eight thousand three hundred and twenty-four women giving birth from 22 countries for model building and 10,045,875 women giving birth from 43 countries for model testing. METHODS: We hypothesised that mathematical models could determine the relationship between clinical-obstetric characteristics and CS. These models generated probabilities of CS that could be compared with the observed CS rates. We devised a three-step approach to generate the global benchmark of CS rates at health facilities: creation of a multi-country reference population, building mathematical models, and testing these models. MAIN OUTCOME MEASURES: Area under the ROC curves, diagnostic odds ratio, expected CS rate, observed CS rate. RESULTS: According to the different versions of the model, areas under the ROC curves suggested a good discriminatory capacity of C-Model, with summary estimates ranging from 0.832 to 0.844. The C-Model was able to generate expected CS rates adjusted for the case-mix of the obstetric population. We have also prepared an e-calculator to facilitate use of C-Model (www.who.int/reproductivehealth/publications/maternal_perinatal_health/c-model/en/). CONCLUSIONS: This article describes the development of a global reference for CS rates. Based on maternal characteristics, this tool was able to generate an individualised expected CS rate for health facilities or groups of health facilities. With C-Model, obstetric teams, health system managers, health facilities, health insurance companies, and governments can produce a customised reference CS rate for assessing use (and overuse) of CS. TWEETABLE ABSTRACT: The C-Model provides a customized benchmark for caesarean section rates in health facilities and systems.
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Cesárea/estatística & dados numéricos , Modelos Estatísticos , Adulto , Estudos Transversais , Feminino , Humanos , Internacionalidade , Gravidez , Valores de ReferênciaRESUMO
OBJECTIVE: To assess the incidence of hypertensive disorders of pregnancy and related severe complications, identify other associated factors and compare maternal and perinatal outcomes in women with and without these conditions. DESIGN: Secondary analysis of the World Health Organization Multicountry Survey on Maternal and Newborn Health (WHOMCS) database. SETTING: Cross-sectional study implemented at 357 health facilities conducting 1000 or more deliveries annually in 29 countries from Africa, Asia, Latin America and the Middle East. POPULATION: All women suffering from any hypertensive disorder during pregnancy, the intrapartum or early postpartum period in the participating hospitals during the study period. METHODS: We calculated the proportion of the pre-specified outcomes in the study population and their distribution according to hypertensive disorders' severity. We estimated the association between them and maternal deaths, near-miss cases, and severe maternal complications using a multilevel logit model. MAIN OUTCOME MEASURES: Hypertensive disorders of pregnancy. Potentially life-threatening conditions among maternal near-miss cases, maternal deaths and cases without severe maternal outcomes. RESULTS: Overall, 8542 (2.73%) women suffered from hypertensive disorders. Incidences of pre-eclampsia, eclampsia and chronic hypertension were 2.16%, 0.28% and 0.29%, respectively. Maternal near-miss cases were eight times more frequent in women with pre-eclampsia, and increased to up to 60 times more frequent in women with eclampsia, when compared with women without these conditions. CONCLUSIONS: The analysis of this large database provides estimates of the global distribution of the incidence of hypertensive disorders of pregnancy. The information on the most frequent complications related to pre-eclampsia and eclampsia could be of interest to inform policies for health systems organisation.