287 research outputs found

    HSC-CLAUDS survey: The star formation rate functions since z ~ 2 and comparison with hydrodynamical simulations

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    Star formation rate functions (SFRFs) give an instantaneous view of the distribution of star formation rates (SFRs) in galaxies at different epochs. They are a complementary and more stringent test for models than the galaxy stellar mass function, which gives an integrated view of the past star formation activity. However, the exploration of SFRFs has been limited thus far due to difficulties in assessing the SFR from observed quantities and probing the SFRF over a wide range of SFRs. We overcome these limitations thanks to an original method that predicts the infrared luminosity from the rest-frame UV/optical color of a galaxy and then its SFR over a wide range of stellar masses and redshifts. We applied this technique to the deep imaging survey HSC-CLAUDS combined with near-infrared and UV photometry. We provide the first SFR functions with reliable measurements in the high- and low-SFR regimes up to z=2z=2 and compare our results with previous observations and four state-of-the-art hydrodynamical simulations.Comment: 29 pages, 19 figure

    The Grosmarin experiment

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    The GROSMARIN (which stands for GrandROSMARIN) cruise is proposed by UMR GĂ©osciences Azur (with fellow french and italian research groups). Its goals are to better characterize active structures along this zone and to assess the resulting seismic hazard in a sort of continuation with respect to the MALISAR experiment, which has already surveyed some active structures through shallow observations. The GROSMARIN cruise is in fact the necessary counterpart to characterize them at depth

    Impacts of climate change on plant diseases – opinions and trends

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    There has been a remarkable scientific output on the topic of how climate change is likely to affect plant diseases in the coming decades. This review addresses the need for review of this burgeoning literature by summarizing opinions of previous reviews and trends in recent studies on the impacts of climate change on plant health. Sudden Oak Death is used as an introductory case study: Californian forests could become even more susceptible to this emerging plant disease, if spring precipitations will be accompanied by warmer temperatures, although climate shifts may also affect the current synchronicity between host cambium activity and pathogen colonization rate. A summary of observed and predicted climate changes, as well as of direct effects of climate change on pathosystems, is provided. Prediction and management of climate change effects on plant health are complicated by indirect effects and the interactions with global change drivers. Uncertainty in models of plant disease development under climate change calls for a diversity of management strategies, from more participatory approaches to interdisciplinary science. Involvement of stakeholders and scientists from outside plant pathology shows the importance of trade-offs, for example in the land-sharing vs. sparing debate. Further research is needed on climate change and plant health in mountain, boreal, Mediterranean and tropical regions, with multiple climate change factors and scenarios (including our responses to it, e.g. the assisted migration of plants), in relation to endophytes, viruses and mycorrhiza, using long-term and large-scale datasets and considering various plant disease control methods

    Mass flows, turbidity currents and other hydrodynamic consequences of small and moderate earthquakes in the Sea of Marmara

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    Earthquake-induced submarine slope destabilization is known to cause mass wasting and turbidity currents, but the hydrodynamic processes associated with these events remain poorly understood. Instrumental records are rare, and this notably limits our ability to interpret marine paleoseismological sedimentary records. An instrumented frame comprising a pressure recorder and a Doppler recording current meter deployed at the seafloor in the Sea of Marmara Central Basin recorded the consequences of a Mw 5.8 earthquake occurring on 26 September 2019 and of a Mw 4.7 foreshock 2 d before. The smaller event caused sediment resuspension and weak current (&lt;4 cm s−1) in the water column. The larger event triggered a complex response involving a debris flow and turbidity currents with variable velocities and orientations, which may have resulted from multiple slope failures. A long delay of 10 h is observed between the earthquake and the passing of the strongest turbidity current. The distance traveled by the sediment particles during the event is estimated to have extended over several kilometers, which could account for a local deposit on a sediment fan at the outlet of a canyon (where the instrument was located), but the sedimentation event did not likely cover the whole basin floor. We show that after a moderate earthquake, delayed turbidity current initiation may occur, possibly by ignition of a cloud of resuspended sediment.</p

    Verso una migliore conoscenza delle strutture del margine Ligure: il progetto GROSMARIN

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    (English Abstract) The Ligurian margin, that is the junction area located between the Ligurian basin and the Southwestern Alps, is a passive margin, seismically active and subjected to gravitative movements. The active deformation in this sector is among the strongest ever experienced in Western Italy and Southern France. The current geodynamics of the basin is not completely understood yet, and somewhat under interest and debate of the scientific community. The latest results on the recent evolution of the Alps-Mediterranean system suggest that the area under study lay close to a domain under extension. The interest for the area is reinforced by its seismic activity that, although of low to moderate energy, acts in an area of high vulnerability. Some historical events involved in fact dramatic social and material damages. The growth of population (that now accounts for more than 2.500.000 inhabitants between Cannes and Genoa), the setting of numerous industries and the tourist business of the area are additional motivation for monitoring the area from the seismic point of view and especially to make specific studies on the seismogenic structures of this sector. Events with magnitude greater than 4.5 to 5.0 are in fact recorded every 5 years, but the area undergoes a rather weak microseismicity that often remains undetected and always poorly located by land seismic networks. The natural risks associated to this sector cannot neglect the presence of steep canyons that incise the offshore margin and favour gravitative slopes. The sediment masses accumulate on top of these canyons and may slip even after an earthquake of moderate magnitude. The GROSMARIN (which stands for GrandROSMARIN) cruise is proposed by UMR GĂ©osciences Azur (with fellow french and italian research groups). It aims at (1) studying the microseismicity along a part of the northern margin of the Ligurian Basin, offshore France and Italy and (2) to realise a 3D tomography by wide-angle seismics. The goal is to better characterize active structures along this zone and to assess the resulting seismic hazard.Published359-360N/A or not JCRope

    Id-1 and Id-2 are markers for metastasis and prognosis in oesophageal squamous cell carcinoma

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    Id protein family consists of four members namely Id-1 to Id-4. Different from other basic helix–loop–helix transcription factors, they lack the DNA binding domain. Id proteins have been shown to be dysregulated in many different cancer types and their prognostic value has also been demonstrated. Recently, Id-1 has been shown to be upregulated in oesophageal squamous cell carcinoma (ESCC). However, the prognostic implications of Id proteins in ESCC have not been reported. We examined the expression of the Id proteins in ESCC cell lines and clinical ESCC specimens and found that Id protein expressions were dysregulated in both the ESCC cell lines and specimens. By correlating the expression levels of Id proteins and the clinicopathological data of our patient cohort, we found that M1 stage tumours had significantly higher nuclear Id-1 expression (P=0.012) while high nuclear Id-1 expression could predict development of distant metastasis within 1 year of oesophagectomy (P=0.005). In addition, high levels of Id-2 expression in both cytoplasmic and nuclear regions predicted longer patient survival (P=0.041). Multivariate analysis showed that high-level expression of Id-2 in both cytoplasmic and nuclear regions and lower level of nuclear Id-1 expression were independent favourable predictors of survival in our ESCC patients. Our results suggest that Id-1 may promote distant metastasis in ESCC, and both Id-1 and Id-2 may be used for prognostication for ESCC patients

    Introduction to the French GEOTRACES North Atlantic Transect (GA01): GEOVIDE cruise

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    The GEOVIDE cruise, a collaborative project within the framework of the international GEOTRACES programme, was conducted along the French-led section in the North Atlantic Ocean (Section GA01), between 15 May and 30 June 2014. In this special issue (https://www.biogeosciences.net/special_issue900.html), results from GEOVIDE, including physical oceanography and trace element and isotope cyclings, are presented among 18 articles. Here, the scientific context, project objectives, and scientific strategy of GEOVIDE are provided, along with an overview of the main results from the articles published in the special issue

    Noninvasive positive pressure ventilation for acute respiratory failure in children: a concise review

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    Noninvasive positive pressure ventilation (NPPV) refers to the delivery of mechanical respiratory support without the use of endotracheal intubation (ETI). The present review focused on the effectiveness of NPPV in children > 1 month of age with acute respiratory failure (ARF) due to different conditions. ARF is the most common cause of cardiac arrest in children. Therefore, prompt recognition and treatment of pediatric patients with pending respiratory failure can be lifesaving. Mechanical respiratory support is a critical intervention in many cases of ARF. In recent years, NPPV has been proposed as a valuable alternative to invasive mechanical ventilation (IMV) in this acute setting. Recent physiological studies have demonstrated beneficial effects of NPPV in children with ARF. Several pediatric clinical studies, the majority of which were noncontrolled or case series and of small size, have suggested the effectiveness of NPPV in the treatment of ARF due to acute airway (upper or lower) obstruction or certain primary parenchymal lung disease, and in specific circumstances, such as postoperative or postextubation ARF, immunocompromised patients with ARF, or as a means to facilitate extubation. NPPV was well tolerated with rare major complications and was associated with improved gas exchange, decreased work of breathing, and ETI avoidance in 22-100% of patients. High FiO2 needs or high PaCO2 level on admission or within the first hours after starting NPPV appeared to be the best independent predictive factors for the NPPV failure in children with ARF. However, many important issues, such as the identification of the patient, the right time for NPPV application, and the appropriate setting, are still lacking. Further randomized, controlled trials that address these issues in children with ARF are recommended
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