71 research outputs found

    The time course of auditory and language-specific mechanisms in compensation for sibilant assimilation

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    Models of spoken-word recognition differ on whether compensation for assimilation is language-specific or depends on general auditory processing. English and French participants were taught words that began or ended with the sibilants /s/ and /∫/. Both languages exhibit some assimilation in sibilant sequences (e.g., /s/ becomes like [∫] in dress shop and classe chargée), but they differ in the strength and predominance of anticipatory versus carryover assimilation. After training, participants were presented with novel words embedded in sentences, some of which contained an assimilatory context either preceding or following. A continuum of target sounds ranging from [s] to [∫] was spliced into the novel words, representing a range of possible assimilation strengths. Listeners' perceptions were examined using a visual-world eyetracking paradigm in which the listener clicked on pictures matching the novel words. We found two distinct language-general context effects: a contrastive effect when the assimilating context preceded the target, and flattening of the sibilant categorization function (increased ambiguity) when the assimilating context followed. Furthermore, we found that English but not French listeners were able to resolve the ambiguity created by the following assimilatory context, consistent with their greater experience with assimilation in this context. The combination of these mechanisms allows listeners to deal flexibly with variability in speech forms

    Water Contamination Reduces the Tolerance of Coral Larvae to Thermal Stress

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    Coral reefs are highly susceptible to climate change, with elevated sea surface temperatures (SST) posing one of the main threats to coral survival. Successful recruitment of new colonies is important for the recovery of degraded reefs following mortality events. Coral larvae require relatively uncontaminated substratum on which to metamorphose into sessile polyps, and the increasing pollution of coastal waters therefore constitutes an additional threat to reef resilience. Here we develop and analyse a model of larval metamorphosis success for two common coral species to quantify the interactive effects of water pollution (copper contamination) and SST. We identify thresholds of temperature and pollution that prevent larval metamorphosis, and evaluate synergistic interactions between these stressors. Our analyses show that halving the concentration of Cu can protect corals from the negative effects of a 2–3°C increase in SST. These results demonstrate that effective mitigation of local impacts can reduce negative effects of global stressors

    De Novo Unbalanced Translocations in Prader-Willi and Angelman Syndrome Might Be the Reciprocal Product of inv dup(15)s

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    The 15q11-q13 region is characterized by high instability, caused by the presence of several paralogous segmental duplications. Although most mechanisms dealing with cryptic deletions and amplifications have been at least partly characterized, little is known about the rare translocations involving this region. We characterized at the molecular level five unbalanced translocations, including a jumping one, having most of 15q transposed to the end of another chromosome, whereas the der(15)(pter->q11-q13) was missing. Imbalances were associated either with Prader-Willi or Angelman syndrome. Array-CGH demonstrated the absence of any copy number changes in the recipient chromosome in three cases, while one carried a cryptic terminal deletion and another a large terminal deletion, already diagnosed by classical cytogenetics. We cloned the breakpoint junctions in two cases, whereas cloning was impaired by complex regional genomic architecture and mosaicism in the others. Our results strongly indicate that some of our translocations originated through a prezygotic/postzygotic two-hit mechanism starting with the formation of an acentric 15qter->q1::q1->qter representing the reciprocal product of the inv dup(15) supernumerary marker chromosome. An embryo with such an acentric chromosome plus a normal chromosome 15 inherited from the other parent could survive only if partial trisomy 15 rescue would occur through elimination of part of the acentric chromosome, stabilization of the remaining portion with telomere capture, and formation of a derivative chromosome. All these events likely do not happen concurrently in a single cell but are rather the result of successive stabilization attempts occurring in different cells of which only the fittest will finally survive. Accordingly, jumping translocations might represent successful rescue attempts in different cells rather than transfer of the same 15q portion to different chromosomes. We also hypothesize that neocentromerization of the original acentric chromosome during early embryogenesis may be required to avoid its loss before cell survival is finally assured

    Impact of COVID-19 on cardiovascular testing in the United States versus the rest of the world

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    Objectives: This study sought to quantify and compare the decline in volumes of cardiovascular procedures between the United States and non-US institutions during the early phase of the coronavirus disease-2019 (COVID-19) pandemic. Background: The COVID-19 pandemic has disrupted the care of many non-COVID-19 illnesses. Reductions in diagnostic cardiovascular testing around the world have led to concerns over the implications of reduced testing for cardiovascular disease (CVD) morbidity and mortality. Methods: Data were submitted to the INCAPS-COVID (International Atomic Energy Agency Non-Invasive Cardiology Protocols Study of COVID-19), a multinational registry comprising 909 institutions in 108 countries (including 155 facilities in 40 U.S. states), assessing the impact of the COVID-19 pandemic on volumes of diagnostic cardiovascular procedures. Data were obtained for April 2020 and compared with volumes of baseline procedures from March 2019. We compared laboratory characteristics, practices, and procedure volumes between U.S. and non-U.S. facilities and between U.S. geographic regions and identified factors associated with volume reduction in the United States. Results: Reductions in the volumes of procedures in the United States were similar to those in non-U.S. facilities (68% vs. 63%, respectively; p = 0.237), although U.S. facilities reported greater reductions in invasive coronary angiography (69% vs. 53%, respectively; p < 0.001). Significantly more U.S. facilities reported increased use of telehealth and patient screening measures than non-U.S. facilities, such as temperature checks, symptom screenings, and COVID-19 testing. Reductions in volumes of procedures differed between U.S. regions, with larger declines observed in the Northeast (76%) and Midwest (74%) than in the South (62%) and West (44%). Prevalence of COVID-19, staff redeployments, outpatient centers, and urban centers were associated with greater reductions in volume in U.S. facilities in a multivariable analysis. Conclusions: We observed marked reductions in U.S. cardiovascular testing in the early phase of the pandemic and significant variability between U.S. regions. The association between reductions of volumes and COVID-19 prevalence in the United States highlighted the need for proactive efforts to maintain access to cardiovascular testing in areas most affected by outbreaks of COVID-19 infection

    Measurement of the mass difference and relative production rate of the Ωb− and Ξb− baryons

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    The mass difference between the Ω − b and Ξ − b baryons is measured using proton-proton collision data collected by the LHCb experiment, corresponding to an integrated luminosity of 9     fb − 1 , and is found to be m ( Ω − b ) − m ( Ξ − b ) = 248.54 ± 0.51 ( stat ) ± 0.38 ( syst )     MeV / c 2 . The mass of the Ω − b baryon is measured to be m ( Ω − b ) = 6045.9 ± 0.5 ( stat ) ± 0.6 ( syst )     MeV / c 2 . This is the most precise determination of the Ω − b mass to date. In addition, the production rate of Ω − b baryons relative to that of Ξ − b baryons is measured for the first time in p p collisions, using an LHCb dataset collected at a center-of-mass energy of 13 TeV and corresponding to an integrated luminosity of 6     fb − 1 . Reconstructing beauty baryons in the kinematic region 2 &lt; η &lt; 6 and p T &lt; 20     GeV / c with their decays to a J / ψ meson and a hyperon, the ratio f Ω − b f Ξ − b × B ( Ω − b → J / ψ Ω − ) B ( Ξ − b → J / ψ Ξ − ) = 0.120 ± 0.008 ( stat ) ± 0.008 ( syst ) , is obtained, where f Ω − b and f Ξ − b are the fragmentation fractions of b quarks into Ω − b and Ξ − b baryons, respectively, and B represents the branching fractions of their respective decays

    Troubles oculo-moteurs et hydrocephalie du nourrisson dans un contexte polymalformatif intense : À propos d’un cas et revue de la littérature internationale

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    Il s’agissait d’un nourrisson YS de 13 mois, admis dans le service de neurochirurgie de l’hôpital national de Niamey pour retard psychomoteur et crises convulsives. La découverte fut impressionnante car en plus d’une association de troubles oculomoteurs hors du commun ; ce patient souffre d’un sittus solitus, d’une communication intra-auriculaire (CIA), d’un ostium secondum de 2,2 mm avec shunt gauche-droit sans rétrécissement sur les cavités cardiaques, d’une tachycardie auscultatoire régulière sur CIA, d’un encombrement bronchique d’une extrême gravité. La TDM cérébral en coupes axiale objectivant une hydrocéphalie tétra ventriculaire avec résorption transépendymaire sur malformation de Dandy-Walker. Le traitement fut chirurgical et l’évolution fut favorable. &nbsp; English title: Oculomotor disorders and hydrocephalia in infants in an intense polymalformative context: A case report and international literature review This study is about a 13-month-old YS infant, admitted to the neurosurgery department of Niamey National Hospital for psychomotor retardation and convulsive seizures. The discovery was impressive because in addition to an association of unusual oculomotor disorders; the patient suffers from a sittus solitus, an intra-auricular communication (IAC), a 2.2 mm ostium secondum with left-right shunt without narrowing on the cardiac chambers, a regular auscultatory tachycardia on IAC, an extremely serious bronchial congestion. The cerebral CT in axial slices objectifying a tetra ventricular hydrocephalus with trans ependymal resorption on Dandy-Walker malformation. The treatment was surgical and the outcome was favorable

    L’hematome sous dural chronique comme complication d’une derivation ventriculo-peritoneale: a propos d’un cas de mauvais menage et Revue de la Litterature Internationale

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    L’hématome sous dural chronique peut être une complication d’une dérivation ventriculo-peritonéale ou lombo-péritonéale d’une hydrocéphalie et dont l’incidence est évaluée entre 0.96 à 43,5%. Les auteurs rapportent un cas de mauvais ménage entre une dérivation ventriculo-peritonéale et un hématome sous dural chronique chez un garçon âgé de 12 ans, dérivé deux ans auparavant. Le diagnostic est scanographique et le traitement consiste à la réalisation d’un ou de deux trous de trépan pour l’évacuation de l’hématome. Les suites opératoires sont généralement satisfaisantes. &nbsp; English Title: Chronic subdural hematoma as a complication of a ventriculo-peritoneal shunt about a case of poor household and International Literature Review Chronic subdural hematoma can be a complication of a ventriculo-peritoneal or lumboperitoneal shunt of hydrocephalus, whose incidence is estimated to be between 0.96% to 43.5%. The authors report a case of bad combination between a ventriculo-peritoneal shunt and a chronic subdural hematoma in a 12-year-old boy, derived two years previously. The diagnosis is CT and the treatment consists of making one or two trephine holes to evacuate the hematoma. The postoperative results are generally satisfactory

    The terrestrial and freshwater invertebrate biodiversity of the archipelagoes of the Barents Sea; Svalbard, Franz Josef Land and Novaya Zemlya

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    Arctic terrestrial ecosystems are generally considered to be species poor, fragile and often isolated. Nonetheless, their intricate complexity, especially that of the invertebrate component, is beginning to emerge. Attention has become focused on the Arctic both due to the importance of this rapidly changing region for the Earth and also the inherent interest of an extreme and unique environment. The three archipelagoes considered here, Svalbard, Franz Josef Land and Novaya Zemlya, delineate the Barents Sea to the west, north and east. This is a region of convergence for Palearctic and Nearctic faunas re-colonising the Arctic following the retreat of the ice after the Last Glacial Maximum (LGM). Despite the harsh Arctic environment and the short period since deglaciation, the archipelagoes of the Barents Sea are inhabited by diverse invertebrate communities. But there is an obvious imbalance in our knowledge of many taxa of each archipelago, and in our knowledge of many taxa. Research effort in Svalbard is increasing rapidly while there are still few reports, particularly in the western literature, from Franz Josef Land and Novaya Zemlya. Nevertheless, there appears to be a surprising degree of dissimilarity between the invertebrate faunas, possibly reflecting colonization history. We provide a baseline synthesis of the terrestrial and freshwater invertebrate fauna of the Barents Sea archipelagoes, highlight the taxa present, the characteristic elements of fauna and the complexity of their biogeography. In doing so, we provide a background from which to assess responses to environmental change for a region under increasing international attention from scientific, industrial and political communities as well as non-governmental organizations and the general public
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