76 research outputs found

    De bronconstructies van Belgisch Nederlands (’t) schijnt : een repliek

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    This is a brief reply to the article by Vliegen in this issue. We argue that, while Vliegen’s suggestion of a link between naar het schijnt and (’t) schijnt is certainly plausible, this need not rule out a scenario in which the emerging use of (’t) schijnt as a particle has also taken its root in (specific uses of) the matrix clause construction het schijnt dat. In modern construction-based approaches to language change, it is accepted that newly developing constructions may have multiple sources. In this perspective, the ‘matrix clause hypothesis’ and the ‘paratactic hypothesis’ are not mutually exclusive

    On the grammaticalization of ('t) schijnt 'it seems' as an evidential particle in colloquial Belgian Dutch

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    Comparing ( ’t) schijnt to (zo) schijnt het (lit. ‘so seems it’), the parenthetical use of the verb schijnen ‘seem’, we argue that ( ’t) schijnt is best analysed as an evidential particle. Although both parenthetical and particle uses of schijnen have been subject to particulization, viz. grammaticalization towards particlehood, this grammaticalization path is bifurcated; while ( ’t) schijnt is best accounted for by the matrix clause hypothesis, (zo) schijnt het fits the parataxis hypothesis and is less grammaticalized, not having reached particle status yet. The possible further grammaticalization of (zo) schijnt het into a more particle-like element is discussed on the basis of recent developments in Netherlandic Dutch, suggesting that distinct grammaticalization paths may lead to similar outcomes. This study calls attention to the need to allow for a certain flexibility of categories when considering cases of grammaticalization such as those affecting schijnen, bearing in mind that each individual instance of ( ’t) schijnt or (zo) schijnt het can be more or less central to the idealized categories of matrix clause, parenthetical or particle

    The diachronic development of zero complementation: A multifactorial analysis of the that/zero alternation with think, suppose, and believe

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    This corpus-based study examines the diachronic development of the that/zero alternation with three verbs of cognition, viz. think, believe, and suppose by means of a stepwise logistic regression analysis. The data comprised a total of (n = 9,720) think, (n = 4,767) believe, and (n = 4,083) suppose tokens from both spoken and written corpora from 1560 to 2012. We test the effect of 11 structural features that have been claimed to predict the presence of the zero complementizer form. Taking our cue from previous research suggesting that there has been a diachronic increase in zero use and applying a rigorous quantitative method to a large set of diachronic data, we examine (i) whether there is indeed a diachronic trend toward more zero use, (ii) whether the conditioning factors proposed in the literature indeed predict the zero form, (iii) to what extent these factors interact, and (iv) whether the predictive power of the conditioning factors becomes stronger or weaker over time. The analysis shows that, contrary to the aforementioned belief that the zero form has been on the increase, there is in fact a steady decrease in zero use. The extent of this decrease is not the same for all verbs. Also, the analysis of interactions with verb type indicates differences between verbs in terms of the predictive power of the conditioning factors. Additional significant interactions emerged, notably with verb, mode (i.e., spoken or written data), and period. The interactions with period show that certain factors that are good predictors of the zero form overall lose predictive power over time

    Performance and Diagnostic Value of Genome-Wide Noninvasive Prenatal Testing in Multiple Gestations.

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    OBJECTIVE: To evaluate the accuracy and diagnostic value of genome-wide noninvasive prenatal testing (NIPT) for the detection of fetal aneuploidies in multiple gestations, with a focus on dichorionic-diamniotic twin pregnancies. METHODS: We performed a retrospective cohort study including data from pregnant women with a twin or higher-order gestation who underwent genome-wide NIPT at one of the eight Belgian genetic centers between November 1, 2013, and March 1, 2020. Chorionicity and amnionicity were determined by ultrasonography. Follow-up invasive testing was carried out in the event of positive NIPT results. Sensitivity and specificity were calculated for the detection of trisomy 21, 18, and 13 in the dichorionic-diamniotic twin cohort. RESULTS: Unique NIPT analyses were performed for 4,150 pregnant women with a multiple gestation and an additional 767 with vanishing gestations. The failure rate in multiple gestations excluding vanishing gestations ranged from 0% to 11.7% among the different genetic centers. Overall, the failure rate was 4.8%, which could be reduced to 1.2% after single resampling. There were no common fetal trisomies detected among the 86 monochorionic-monoamniotic and 25 triplet cases. Two monochorionic-diamniotic twins had an NIPT result indicative of a trisomy 21, which was confirmed in both fetuses. Among 2,716 dichorionic-diamniotic twin gestations, a sensitivity of 100% (95% CI 74.12-100%) and a specificity of 100% (95% CI 99.86-100%) was reached for trisomy 21 (n=12). For trisomy 18 (n=3), the respective values were 75% (95% CI 30.06-95.44%) sensitivity and 100% (95% CI 99.86-100%) specificity, and for trisomy 13 (n=2), 100% (95% CI 20.65-100%) sensitivity and 99.96% (95% CI 99.79-99.99%) specificity. In the vanishing gestation group, 28 NIPT results were positive for trisomy 21, 18, or 13, with only five confirmed trisomies. CONCLUSION: Genome-wide NIPT performed accurately for detection of aneuploidy in dichorionic-diamniotic twin gestations

    Long-term thermal sensitivity of Earth’s tropical forests

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    The sensitivity of tropical forest carbon to climate is a key uncertainty in predicting global climate change. Although short-term drying and warming are known to affect forests, it is unknown if such effects translate into long-term responses. Here, we analyze 590 permanent plots measured across the tropics to derive the equilibrium climate controls on forest carbon. Maximum temperature is the most important predictor of aboveground biomass (−9.1 megagrams of carbon per hectare per degree Celsius), primarily by reducing woody productivity, and has a greater impact per °C in the hottest forests (>32.2°C). Our results nevertheless reveal greater thermal resilience than observations of short-term variation imply. To realize the long-term climate adaptation potential of tropical forests requires both protecting them and stabilizing Earth’s climate

    Taking the pulse of Earth's tropical forests using networks of highly distributed plots

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    Tropical forests are the most diverse and productive ecosystems on Earth. While better understanding of these forests is critical for our collective future, until quite recently efforts to measure and monitor them have been largely disconnected. Networking is essential to discover the answers to questions that transcend borders and the horizons of funding agencies. Here we show how a global community is responding to the challenges of tropical ecosystem research with diverse teams measuring forests tree-by-tree in thousands of long-term plots. We review the major scientific discoveries of this work and show how this process is changing tropical forest science. Our core approach involves linking long-term grassroots initiatives with standardized protocols and data management to generate robust scaled-up results. By connecting tropical researchers and elevating their status, our Social Research Network model recognises the key role of the data originator in scientific discovery. Conceived in 1999 with RAINFOR (South America), our permanent plot networks have been adapted to Africa (AfriTRON) and Southeast Asia (T-FORCES) and widely emulated worldwide. Now these multiple initiatives are integrated via ForestPlots.net cyber-infrastructure, linking colleagues from 54 countries across 24 plot networks. Collectively these are transforming understanding of tropical forests and their biospheric role. Together we have discovered how, where and why forest carbon and biodiversity are responding to climate change, and how they feedback on it. This long-term pan-tropical collaboration has revealed a large long-term carbon sink and its trends, as well as making clear which drivers are most important, which forest processes are affected, where they are changing, what the lags are, and the likely future responses of tropical forests as the climate continues to change. By leveraging a remarkably old technology, plot networks are sparking a very modern revolution in tropical forest science. In the future, humanity can benefit greatly by nurturing the grassroots communities now collectively capable of generating unique, long-term understanding of Earth's most precious forests. Resumen Los bosques tropicales son los ecosistemas mĂĄs diversos y productivos del mundo y entender su funcionamiento es crĂ­tico para nuestro futuro colectivo. Sin embargo, hasta hace muy poco, los esfuerzos para medirlos y monitorearlos han estado muy desconectados. El trabajo en redes es esencial para descubrir las respuestas a preguntas que trascienden las fronteras y los plazos de las agencias de financiamiento. AquĂ­ mostramos cĂłmo una comunidad global estĂĄ respondiendo a los desafĂ­os de la investigaciĂłn en ecosistemas tropicales a travĂ©s de diversos equipos realizando mediciones ĂĄrbol por ĂĄrbol en miles de parcelas permanentes de largo plazo. Revisamos los descubrimientos mĂĄs importantes de este trabajo y discutimos cĂłmo este proceso estĂĄ cambiando la ciencia relacionada a los bosques tropicales. El enfoque central de nuestro esfuerzo implica la conexiĂłn de iniciativas locales de largo plazo con protocolos estandarizados y manejo de datos para producir resultados que se puedan trasladar a mĂșltiples escalas. Conectando investigadores tropicales, elevando su posiciĂłn y estatus, nuestro modelo de Red Social de InvestigaciĂłn reconoce el rol fundamental que tienen, para el descubrimiento cientĂ­fico, quienes generan o producen los datos. Concebida en 1999 con RAINFOR (SuramĂ©rica), nuestras redes de parcelas permanentes han sido adaptadas en África (AfriTRON) y el sureste asiĂĄtico (T-FORCES) y ampliamente replicadas en el mundo. Actualmente todas estas iniciativas estĂĄn integradas a travĂ©s de la ciber-infraestructura de ForestPlots.net, conectando colegas de 54 paĂ­ses en 24 redes diferentes de parcelas. Colectivamente, estas redes estĂĄn transformando nuestro conocimiento sobre los bosques tropicales y el rol de Ă©stos en la biĂłsfera. Juntos hemos descubierto cĂłmo, dĂłnde y porquĂ© el carbono y la biodiversidad de los bosques tropicales estĂĄ respondiendo al cambio climĂĄtico y cĂłmo se retroalimentan. Esta colaboraciĂłn pan-tropical de largo plazo ha expuesto un gran sumidero de carbono y sus tendencias, mostrando claramente cuĂĄles son los factores mĂĄs importantes, quĂ© procesos se ven afectados, dĂłnde ocurren los cambios, los tiempos de reacciĂłn y las probables respuestas futuras mientras el clima continĂșa cambiando. Apalancando lo que realmente es una tecnologĂ­a antigua, las redes de parcelas estĂĄn generando una verdadera y moderna revoluciĂłn en la ciencia tropical. En el futuro, la humanidad puede beneficiarse enormemente si se nutren y cultivan comunidades de investigadores de base, actualmente con la capacidad de generar informaciĂłn Ășnica y de largo plazo para entender los que probablemente son los bosques mĂĄs preciados de la tierra. Resumo Florestas tropicais sĂŁo os ecossistemas mais diversos e produtivos da Terra. Embora uma boa compreensĂŁo destas florestas seja crucial para o nosso futuro coletivo, atĂ© muito recentemente os esforços de mediçÔes e monitoramento foram amplamente desconexos. É essencial formarmos redes para obtermos respostas que transcendem fronteiras e horizontes de agĂȘncias financiadoras. Neste estudo nĂłs mostramos como uma comunidade global estĂĄ respondendo aos desafios da pesquisa de ecossistemas tropicais, com equipes diversas medindo florestas, ĂĄrvore por ĂĄrvore, em milhares de parcelas monitoradas Ă  longo prazo. NĂłs revisamos as maiores descobertas cientĂ­ficas deste trabalho, e mostramos tambĂ©m como este processo estĂĄ mudando a ciĂȘncia de florestas tropicais. Nossa abordagem principal envolve unir iniciativas de base a protocolos padronizados e gerenciamento de dados a fim de gerar resultados robustos em escalas ampliadas. Ao conectar pesquisadores tropicais e elevar seus status, nosso modelo de Rede de Pesquisa Social reconhece o papel-chave do produtor dos dados na descoberta cientĂ­fica. Concebida em 1999 com o RAINFOR (AmĂ©rica do Sul), nossa rede de parcelas permanentes foi adaptada para África (AfriTRON) e Sudeste asiĂĄtico (T-FORCES), e tem sido extensamente reproduzida em todo o mundo. Agora estas mĂșltiplas iniciativas estĂŁo integradas atravĂ©s de uma infraestrutura cibernĂ©tica do ForestPlots.net, conectando colegas de 54 paĂ­ses de 24 redes de parcelas. Estas iniciativas estĂŁo transformando coletivamente o entendimento das florestas tropicais e seus papĂ©is na biosfera. Juntos nĂłs descobrimos como, onde e por que o carbono e a biodiversidade da floresta estĂŁo respondendo Ă s mudanças climĂĄticas, e seus efeitos de retroalimentação. Esta duradoura colaboração pantropical revelou um grande sumidouro de carbono persistente e suas tendĂȘncias, assim como tem evidenciado quais direcionadores sĂŁo mais importantes, quais processos florestais sĂŁo mais afetados, onde eles estĂŁo mudando, seus atrasos no tempo de resposta, e as provĂĄveis respostas das florestas tropicais conforme o clima continua a mudar. Dessa forma, aproveitando uma notĂĄvel tecnologia antiga, redes de parcelas acendem faĂ­scas de uma moderna revolução na ciĂȘncia das florestas tropicais. No futuro a humanidade pode se beneficiar incentivando estas comunidades basais que agora sĂŁo coletivamente capazes de gerar conhecimentos Ășnicos e duradouros sobre as florestas mais preciosas da Terra. RĂ©sume Les forĂȘts tropicales sont les Ă©cosystĂšmes les plus diversifiĂ©s et les plus productifs de la planĂšte. Si une meilleure comprĂ©hension de ces forĂȘts est essentielle pour notre avenir collectif, jusqu'Ă  tout rĂ©cemment, les efforts dĂ©ployĂ©s pour les mesurer et les surveiller ont Ă©tĂ© largement dĂ©connectĂ©s. La mise en rĂ©seau est essentielle pour dĂ©couvrir les rĂ©ponses Ă  des questions qui dĂ©passent les frontiĂšres et les horizons des organismes de financement. Nous montrons ici comment une communautĂ© mondiale relĂšve les dĂ©fis de la recherche sur les Ă©cosystĂšmes tropicaux avec diverses Ă©quipes qui mesurent les forĂȘts arbre aprĂšs arbre dans de milliers de parcelles permanentes. Nous passons en revue les principales dĂ©couvertes scientifiques de ces travaux et montrons comment ce processus modifie la science des forĂȘts tropicales. Notre approche principale consiste Ă  relier les initiatives de base Ă  long terme Ă  des protocoles standardisĂ©s et une gestion de donnĂ©es afin de gĂ©nĂ©rer des rĂ©sultats solides Ă  grande Ă©chelle. En reliant les chercheurs tropicaux et en Ă©levant leur statut, notre modĂšle de rĂ©seau de recherche sociale reconnaĂźt le rĂŽle clĂ© de l'auteur des donnĂ©es dans la dĂ©couverte scientifique. Conçus en 1999 avec RAINFOR (AmĂ©rique du Sud), nos rĂ©seaux de parcelles permanentes ont Ă©tĂ© adaptĂ©s Ă  l'Afrique (AfriTRON) et Ă  l'Asie du Sud-Est (T-FORCES) et largement imitĂ©s dans le monde entier. Ces multiples initiatives sont dĂ©sormais intĂ©grĂ©es via l'infrastructure ForestPlots.net, qui relie des collĂšgues de 54 pays Ă  travers 24 rĂ©seaux de parcelles. Ensemble, elles transforment la comprĂ©hension des forĂȘts tropicales et de leur rĂŽle biosphĂ©rique. Ensemble, nous avons dĂ©couvert comment, oĂč et pourquoi le carbone forestier et la biodiversitĂ© rĂ©agissent au changement climatique, et comment ils y rĂ©agissent. Cette collaboration pan-tropicale Ă  long terme a rĂ©vĂ©lĂ© un important puits de carbone Ă  long terme et ses tendances, tout en mettant en Ă©vidence les facteurs les plus importants, les processus forestiers qui sont affectĂ©s, les endroits oĂč ils changent, les dĂ©calages et les rĂ©actions futures probables des forĂȘts tropicales Ă  mesure que le climat continue de changer. En tirant parti d'une technologie remarquablement ancienne, les rĂ©seaux de parcelles dĂ©clenchent une rĂ©volution trĂšs moderne dans la science des forĂȘts tropicales. À l'avenir, l'humanitĂ© pourra grandement bĂ©nĂ©ficier du soutien des communautĂ©s de base qui sont maintenant collectivement capables de gĂ©nĂ©rer une comprĂ©hension unique et Ă  long terme des forĂȘts les plus prĂ©cieuses de la Terre. Abstrak Hutan tropika adalah di antara ekosistem yang paling produktif dan mempunyai kepelbagaian biodiversiti yang tinggi di seluruh dunia. Walaupun pemahaman mengenai hutan tropika amat penting untuk masa depan kita, usaha-usaha untuk mengkaji dan mengawas hutah-hutan tersebut baru sekarang menjadi lebih diperhubungkan. Perangkaian adalah sangat penting untuk mencari jawapan kepada soalan-soalan yang menjangkaui sempadan dan batasan agensi pendanaan. Di sini kami menunjukkan bagaimana sebuah komuniti global bertindak balas terhadap cabaran penyelidikan ekosistem tropika melalui penglibatan pelbagai kumpulan yang mengukur hutan secara pokok demi pokok dalam beribu-ribu plot jangka panjang. Kami meninjau semula penemuan saintifik utama daripada kerja ini dan menunjukkan bagaimana proses ini sedang mengubah bidang sains hutan tropika. Teras pendekatan kami memberi tumpuan terhadap penghubungan inisiatif akar umbi jangka panjang dengan protokol standar serta pengurusan data untuk mendapatkan hasil skala besar yang kukuh. Dengan menghubungkan penyelidik-penyelidik tropika dan meningkatkan status mereka, model Rangkaian Penyelidikan Sosial kami mengiktiraf kepentingan peranan pengasas data dalam penemuan saintifik. Bermula dengan pengasasan RAINFOR (Amerika Selatan) pada tahun 1999, rangkaian-rangkaian plot kekal kami kemudian disesuaikan untuk Afrika (AfriTRON) dan Asia Tenggara (T-FORCES) dan selanjutnya telah banyak dicontohi di seluruh dunia. Kini, inisiatif-inisiatif tersebut disepadukan melalui infrastruktur siber ForestPlots.net yang menghubungkan rakan sekerja dari 54 negara di 24 buah rangkaian plot. Secara kolektif, rangkaian ini sedang mengubah pemahaman tentang hutan tropika dan peranannya dalam biosfera. Kami telah bekerjasama untuk menemukan bagaimana, di mana dan mengapa karbon serta biodiversiti hutan bertindak balas terhadap perubahan iklim dan juga bagaimana mereka saling bermaklum balas. Kolaborasi pan-tropika jangka panjang ini telah mendedahkan sebuah sinki karbon jangka panjang serta arah alirannya dan juga menjelaskan pemandu-pemandu perubahan yang terpenting, di mana dan bagaimana proses hutan terjejas, masa susul yang ada dan kemungkinan tindakbalas hutan tropika pada perubahan iklim secara berterusan di masa depan. Dengan memanfaatkan pendekatan lama, rangkaian plot sedang menyalakan revolusi yang amat moden dalam sains hutan tropika. Pada masa akan datang, manusia sejagat akan banyak mendapat manfaat jika memupuk komuniti-komuniti akar umbi yang kini berkemampuan secara kolektif menghasilkan pemahaman unik dan jangka panjang mengenai hutan-hutan yang paling berharga di dunia

    COVID-19 symptoms at hospital admission vary with age and sex: results from the ISARIC prospective multinational observational study

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    Background: The ISARIC prospective multinational observational study is the largest cohort of hospitalized patients with COVID-19. We present relationships of age, sex, and nationality to presenting symptoms. Methods: International, prospective observational study of 60 109 hospitalized symptomatic patients with laboratory-confirmed COVID-19 recruited from 43 countries between 30 January and 3 August 2020. Logistic regression was performed to evaluate relationships of age and sex to published COVID-19 case definitions and the most commonly reported symptoms. Results: ‘Typical’ symptoms of fever (69%), cough (68%) and shortness of breath (66%) were the most commonly reported. 92% of patients experienced at least one of these. Prevalence of typical symptoms was greatest in 30- to 60-year-olds (respectively 80, 79, 69%; at least one 95%). They were reported less frequently in children (≀ 18 years: 69, 48, 23; 85%), older adults (≄ 70 years: 61, 62, 65; 90%), and women (66, 66, 64; 90%; vs. men 71, 70, 67; 93%, each P < 0.001). The most common atypical presentations under 60 years of age were nausea and vomiting and abdominal pain, and over 60 years was confusion. Regression models showed significant differences in symptoms with sex, age and country. Interpretation: This international collaboration has allowed us to report reliable symptom data from the largest cohort of patients admitted to hospital with COVID-19. Adults over 60 and children admitted to hospital with COVID-19 are less likely to present with typical symptoms. Nausea and vomiting are common atypical presentations under 30 years. Confusion is a frequent atypical presentation of COVID-19 in adults over 60 years. Women are less likely to experience typical symptoms than men
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