849 research outputs found
Variability of stamp impression measurements under different apposition conditions
When a forensic document examiner obtains differences in size measurements between a questioned and reference stamp impressions, it may be difficult to assess whether such findings might be due to the use of the same stamp in different apposition conditions or are due to the use of different stamps. To address this issue, the present work has studied the variability of size measurements of stamp impressions apposed in various (pressure, humidity and temperature) conditions. Different stamps were also used to evaluate the influence of the fabricant, the matrix (photopolymer or rubber) and the inking type (self-inking and handstamp). While statistical tests sometimes indicated differences in the results, the measurement distributions overlapped for all kind of conditions (same stamps, different stamps), except for the two stamps produced by different manufacturers. Based on the findings of this study, a difference above 0.09 cm would support the hypothesis that two different stamps were used to produce the impressions. However, size differences below 0.09 cm were also encountered for impressions made using different stamps. The maximal size difference was actually measured for two stamps produced by different manufacturers (up to 0.29 cm)
Applying causality and bicausality to multi-port elements in Bond Graphs
International audienceThe introduction of the bicausality concept in the bond graph language has allowed new analytical methodologies of a system, for instance in the context of model inversion, mechatronic system sizing and control. The causality assignment generally imposes the way these constitutive relations have to be used. In the case of linear multi-port elements, derivative causality or of bicausality is not necessarily possible. The conditions for the existence of a causal configuration are related to the form of the constitutive relation of the multi-port element. In this paper, we propose to inspect this condition and then to focus on the use of the causality applied to the linear multi-port elements. We show that the constitutive relations of any linear multi-port element may be used to determine quickly what kind of causality assignment does exist and what could be determined using different schemes of calculus. It clearly appears that this approach may be applied in other contexts and may have interesting applications on system sizing, identification and control
Antiplatelet therapy in atherothrombotic diseases : similarities and differences across guidelines
Antiplatelet therapy, mainly consisting of aspirin and P2Y12 receptor antagonists, is the
cornerstone of the pharmacological treatment and prevention of atherothrombotic
diseases. Its use, especially in secondary cardiovascular prevention, has significantly
improved patient clinical outcomes in the last decades. Primary safety endpoint
(i.e., bleeding complications) remain a major drawback of antiplatelet drugs. National
and international societies have published and regularly updated guidelines for antiplatelet
therapy aiming to provide clinicians with practical recommendations for a better handling of
these drugs in various clinical settings. Many recommendations find common ground
between international guidelines, but certain strategies vary across the countries,
particularly with regard to the choice of molecules, dosage, and treatment duration. In
this review, we detail and discuss the main antiplatelet therapy indications in the light of the
different published guidelines and the significant number of recently published clinical trials
and meta-analyses and highlight the areas that deserve further investigation in order to
improve antiplatelet therapy in patients with atherothrombotic diseases
Woodwork
February, 1938."Cooperative Extension Work in Agriculture and Home Economics, University of Missouri, College of Agriculture and the United States Department of Agriculture cooperating."Title from cover
Coherent motion of stereocilia assures the concerted gating of hair-cell transduction channels
The hair cell's mechanoreceptive organelle, the hair bundle, is highly
sensitive because its transduction channels open over a very narrow range of
displacements. The synchronous gating of transduction channels also underlies
the active hair-bundle motility that amplifies and tunes responsiveness. The
extent to which the gating of independent transduction channels is coordinated
depends on how tightly individual stereocilia are constrained to move as a
unit. Using dual-beam interferometry in the bullfrog's sacculus, we found that
thermal movements of stereocilia located as far apart as a bundle's opposite
edges display high coherence and negligible phase lag. Because the mechanical
degrees of freedom of stereocilia are strongly constrained, a force applied
anywhere in the hair bundle deflects the structure as a unit. This feature
assures the concerted gating of transduction channels that maximizes the
sensitivity of mechanoelectrical transduction and enhances the hair bundle's
capacity to amplify its inputs.Comment: 24 pages, including 6 figures, published in 200
Genetic Susceptibility Determines β-Cell Function and Fasting Glycemia Trajectories Throughout Childhood: A 12-Year Cohort Study (EarlyBird 76)
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Variability in frost occurrence under climate change and consequent risk of damage to trees of western Quebec, Canada
Climate change affects timings, frequency, and intensity of frost events in northern ecosystems. However, our understanding of the impacts that frost will have on growth and survival of plants is still limited. When projecting the occurrence of frost, the internal variability and the different underlying physical formulations are two major sources of uncertainty of climate models. We use 50 climate simulations produced by a single-initial large climate ensemble and five climate simulations produced by different pairs of global and regional climate models based on the concentration pathway (RCP 8.5) over a latitudinal transect covering the temperate and boreal ecosystems of western Quebec, Canada, during 1955–2099 to provide a first-order estimate of the relative importance of these two sources of uncertainty on the occurrence of frost, i.e. when air temperature is < 0 °C, and their potential damage to trees. The variation in the date of the last spring frost was larger by 21 days (from 46 to 25 days) for the 50 climate simulations compared to the 5 different pairs of climate models. When considering these two sources of uncertainty in an eco-physiological model simulating the timings of budbreak for trees of northern environment, results show that 20% of climate simulations expect that trees will be exposed to frost even in 2090. Thus, frost damage to trees remains likely under global warming
REE concentration processes in ion adsorption deposits: evidence from the Ambohimirahavavy alkaline complex in Madagascar
Ion adsorption deposits, in which the rare earth elements (REE) occur adsorbed onto clay mineral surfaces, currently provide the world�s dominant supply of heavy REE (Gd-Lu). Concentration of REE within ion adsorption deposits has been proposed to be a dominantly supergene process, where easily degradable REE-minerals (e.g. REE-fluorcarbonates) break down and release REE that are then adsorbed onto clay mineral surfaces in the weathered material. Here we present data from the Cenozoic Ambohimirahavavy alkaline complex in Madagascar, with the aim of further constraining controls on the formation and HREE enrichment processes in ion adsorption deposits. The laterite weathering profiles described here are developed on alkaline igneous rocks, including both SiO2-undersaturated and oversaturated lithologies. The latter group includes REE mineralised peralkaline granitic pegmatites and granitic dykelets. The weathering mineralogy includes gibbsite, clay minerals and minor Fe and Mn oxyhydroxides. X-ray diffraction and infrared spectroscopy show that the clay fraction in all sites is dominated by kaolinite and halloysite (7�à and 10�à ). Extraction with ammonium sulfate (0.5�M (NH4)2SO4, pH�=�4; removes weakly adsorbed metals retained on the solid surface and dissolves carbonates) indicates that, in the different profiles and along the same profile, the leachable REE content is heterogeneous, ranging from 5 to 2300�mg/kg total REE, with 1 to 32 heavy REE. Leaching with magnesium chloride (0.5�M MgCl2, pH�=�6; removes only weakly adsorbed REE) releases similar total REE concentrations, suggesting that most of the leachable REE are adsorbed onto mineral surfaces. In most of the laterite profiles, the amount of leachable REE continuously increases with depth up to the saprock. Recovery rates depend on the REE atomic number, generally decreasing from La to Lu except for Ce which is invariably low. In the Ambohimirahavavy complex, the nature of the protolith is the main factor controlling the amount of easily leachable REE in the laterite weathering profile. Hydrology and topography are secondary factors. The most favourable protoliths include SiO2-undersaturated volcanic lithologies and altered mudstone with granitic dykelets. The main primary REE minerals include agpaitic minerals (eudialyte) and allanite-(Ce). Locally in granitic pegmatite dykes, autometasomatism by late magmatic fluids inhibits formation of ion adsorption ore by transforming easily weathered agpaitic minerals into unweatherable zircon
CRY2 Is Associated with Depression
Abnormalities in the circadian clockwork often characterize patients with major depressive and bipolar disorders. Circadian clock genes are targets of interest in these patients. CRY2 is a circadian gene that participates in regulation of the evening oscillator. This is of interest in mood disorders where a lack of switch from evening to morning oscillators has been postulated.We observed a marked diurnal variation in human CRY2 mRNA levels from peripheral blood mononuclear cells and a significant up-regulation (P = 0.020) following one-night total sleep deprivation, a known antidepressant. In depressed bipolar patients, levels of CRY2 mRNA were decreased (P = 0.029) and a complete lack of increase was observed following sleep deprivation. To investigate a possible genetic contribution, we undertook SNP genotyping of the CRY2 gene in two independent population-based samples from Sweden (118 cases and 1011 controls) and Finland (86 cases and 1096 controls). The CRY2 gene was significantly associated with winter depression in both samples (haplotype analysis in Swedish and Finnish samples: OR = 1.8, P = 0.0059 and OR = 1.8, P = 0.00044, respectively).We propose that a CRY2 locus is associated with vulnerability for depression, and that mechanisms of action involve dysregulation of CRY2 expression
Association of Eating and Sleeping Intervals With Weight Change Over Time: The Daily24 Cohort.
Background We aim to evaluate the association between meal intervals and weight trajectory among adults from a clinical cohort. Methods and Results This is a multisite prospective cohort study of adults recruited from 3 health systems. Over the 6-month study period, 547 participants downloaded and used a mobile application to record the timing of meals and sleep for at least 1 day. We obtained information on weight and comorbidities at each outpatient visit from electronic health records for up to 10 years before until 10 months after baseline. We used mixed linear regression to model weight trajectories. Mean age was 51.1 (SD 15.0) years, and body mass index was 30.8 (SD 7.8) kg/
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