1,376 research outputs found

    A motivic homotopy theory without A1-invariance

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    In this paper, we continue the program initiated by Kahn\u2013Saito\u2013Yamazaki by constructing and studying an unstable motivic homotopy category with modulus MH(k), extending the Morel\u2013Voevodsky construction from smooth schemes over a field k to certain diagrams of schemes. We present this category as a candidate environment for studying representability problems for non A1-invariant generalized cohomology theories

    Large-scale progradation, demise and rebirth of a high-relief carbonate platform (Triassic, Lombardy Southern Alps, Italy)

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    The Upper Anisian to Early Carnian succession of the Middle Val Brembana-Pegherolo Massif (Central Southern Alps of Italy) records a complete depositional cycle from platform inception to growth, demise and rebirth. The depositional architecture of this system reflects different evolutionary stages: an inception stage which postdates a previous drowning of an Anisian carbonate platform with progradation of the carbonate platform from the nucleation areas, an aggradational stage with increasing water depth in the basins, a progradational stage where steep slopes composed of margin-derived breccias develop and a final crisis corresponding to the subaerial exposure of the platform top, followed by the deposition of shales in the basin before the rebirth of a different type of carbonate factory. The record of this evolution reflects the effects of the change in accommodation space (interplay of subsidence and eustacy), which controls the type and storage sites of the sediments produced by the carbonate factory. The effects of the changes in accommodation space are recorded in the shallow water platform as well as in the intraplatform basins, where the sediments, delivered at different rates from the platform top are stored. As a consequence, the aggradational stage corresponds to reduced sedimentation in the basins (i.e. sediments are stored on the platform top) whereas during progradation resedimented limestones are more common in the basin. Subaerial exposure rapidly halted the carbonate production on the platform top, while a major input of shales (probably reflecting a climate change and/or lowering of the base level) is recorded in the basin, where shales onlap the slope of the previous carbonate system. The rebirth of the carbonate factory after subaerial exposure of the platform top is characterized by a different composition of the carbonate factory, probably reflecting changes of the environmental conditions. The step-by-step recording of the evolution of the carbonate system represents a unique opportunity to record a seismic-scale complete evolutionary cycle of a carbonate system in its different sub-environments, from the platform top to the basin

    Spatiotemporal profile of peri-saccadic contrast sensitivity

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    Sensitivity to luminance contrast is reduced just before and during saccades (saccadic suppression), whereas sensitivity to color contrast is unimpaired peri-saccadically and enhanced post-saccadically. The exact spatiotemporal map of these perceptual effects is as yet unknown. Here, we measured detection thresholds for briefly flashed Gaussian blobs modulated in either luminance or chromatic contrast, displayed at a range of eccentricities. Sensitivity to luminance contrast was reduced peri-saccadically by a scaling factor, which was almost constant across retinal space. Saccadic suppression followed a similar time course across all tested eccentricities and was maximal shortly after the saccade onset. Sensitivity to chromatic contrast was enhanced post-saccadically at all tested locations. The enhancement was not specifically linked to the execution of saccades, as it was also observed following a displacement of retinal images comparable to that caused by a saccade. We conclude that luminance and chromatic contrast sensitivities are subject to distinct modulations at the time of saccades, resulting from independent neural processes

    Rigidity for relative 0-Cycles

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    We present a relation between the classical Chow group of relative 0-cycles on a regular scheme X , projective and flat over an excellent Henselian discrete valuation ring, and the Levine-Weibel Chow group of 0-cycles on the special fiber. We show that these two Chow groups are isomorphic with finite coefficients under extra assumptions. This generalizes a result of Esnault, Kerz and Wittenberg

    Semi-purity for cycles with modulus

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    In this paper, we prove a form of purity property for the = (P 1 , 1e)-invariant replacement h 0 (X) of the Yoneda object Ztr(X) for a proper modulus pair X = (X, X 1e) over a field k, consisting of a smooth proper k-scheme and an effective Cartier divisor on it. As application, we prove the analogue in the modulus setting of Voevodsky\u2019s fundamental theorem on the homotopy invariance of the cohomology of homotopy invariant sheaves with transfers, based on a main result of [20]. This plays an essential role in the development of the theory of motives with modulus, and among other things implies the existence of a homotopy t-structure on the category MDMeff (k) of Kahn-Saito-Yamazaki

    Quality of dying in hospital general wards: a cross-sectional study about the end-of-life care

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    Abstract Background In the last decade, access to national palliative care programs have improved, however a large proportion of patients continued to die in hospital, particularly within internal medicine wards. Objectives To describe treatments, symptoms and clinical management of adult patients at the end of their life and explore whether these differ according to expectation of death. Methods Single-centre cross-sectional study performed in the medical and surgical wards of a large tertiary-level university teaching hospital in the north of Italy. Data on nursing interventions and diagnostic procedure in proximity of death were collected after interviewing the nurse and the physician responsible for the patient. Relationship between nursing treatments delivered and patients’ characteristics, quality of dying and nurses’ expectation about death was summarized by means of multiple correspondence analysis (MCA). Results Few treatments were found statistically associated with expectation of death in the 187 patients included. In the last 48 h, routine (70.6%) and biomarkers (41.7%) blood tests were performed, at higher extent on patients whose death was not expected. Many symptoms classified as severe were reported when death was highly expected, except for agitation and respiratory fatigue which were reported when death was moderately expected. A high Norton score and absence of anti-bedsore mattress were associated with unexpected death and poor quality of dying, as summarized by MCA. Quality of dying was perceived as good by nurses when death was moderately and highly expected. Physicians rated more frequently than nurses the quality of dying as good or very good, respectively 78.6 and 57.8%, denoting a fair agreement between the two professionals (k = 0.24, P <  0.001). The palliative care consultant was requested for only two patients. Conclusion Staff in medical and surgical wards still deal inadequately with the needs of dying people. Presence of hospital-based specialist palliative care could lead to improvements in the patients’ quality of life

    Can we withdraw immunosuppressants in patients with lupus nephritis in remission? An expert debate.

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    Lupus nephritis (LN) treatment requires an initial intensive period of therapy followed by a long-term maintenance treatment in order to stabilize disease control and eventually reach renal remission. In this section, Authors discuss the feasibility of safely lowering and even suspending maintenance therapy in LN patients having entered remission, highlighting hurdles in predicting the depth and durability of disease quiescence together with the need for minimizing potentially toxic therapies. Even though no firm conclusions can still be drawn, the treating physician has to find the wise balance between disease control and treatment-related drawbacks by following patients closely and recognizing as early as possible the ones who are likely to reach a deep and durable renal remission; there is consensus that is these are the only patients in whom a potential safe complete withdrawal can be foreseen so far

    Tube-jack testing for irregular masonry walls: Regular masonry wall testing

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    This paper presents the continued development of a novel non-destructive testing method termed tube-jack testing. The goal of the tube-jack system is to provide an enhanced and less destructive method than traditional flatjack testing for determination of mechanical characteristics and local stress states in irregular masonrywalls. Single tubejack testswere performed, using previously developed rubber tube-jacks, in regular masonry walls of granite and cementlimemortar. A traditional flat-jack test was also performed in the same masonry wall. Conclusions suggest that tube-jacks are successful in applying pressure to the masonry at low stress states.The authors would like to acknowledge the Fundação para a Ciência e Tecnologia, which supported this research work as a part of the Project “Improved and innovative techniques for the diagnosis and monitoring of historical masonry”, PTDC/ECM/104045/2008

    Fast ion energy distribution from third harmonic radio frequency heating measured with a single crystal diamond detector at the Joint European Torus

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    Neutron spectroscopy measurements with a single crystal diamond detector have been carried out at JET, for the first time in an experiment aimed at accelerating deuterons to MeV energies with radio frequency heating at the third harmonic. Data are interpreted by means of the expected response function of the detector and are used to extract parameters of the highly non-Maxwellian distribution function generated in this scenario. A comparison with observations using a time of flight and liquid scintillator neutron spectrometers is also presented. The results demonstrate the capability of diamond detectors to contribute to fast ion physics studies at JET and are of more general relevance in view of the application of such detectors for spectroscopy measurements in the neutron camera of next step tokamak devices.EURATOM 63305
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