991 resultados para GPU - graphics processing unit


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The aim was to propose a strategy for finding reasonable compromises between image noise and dose as a function of patient weight. Weighted CT dose index (CTDI(w)) was measured on a multidetector-row CT unit using CTDI test objects of 16, 24 and 32 cm in diameter at 80, 100, 120 and 140 kV. These test objects were then scanned in helical mode using a wide range of tube currents and voltages with a reconstructed slice thickness of 5 mm. For each set of acquisition parameter image noise was measured and the Rose model observer was used to test two strategies for proposing a reasonable compromise between dose and low-contrast detection performance: (1) the use of a unique noise level for all test object diameters, and (2) the use of a unique dose efficacy level defined as the noise reduction per unit dose. Published data were used to define four weight classes and an acquisition protocol was proposed for each class. The protocols have been applied in clinical routine for more than one year. CTDI(vol) values of 6.7, 9.4, 15.9 and 24.5 mGy were proposed for the following weight classes: 2.5-5, 5-15, 15-30 and 30-50 kg with image noise levels in the range of 10-15 HU. The proposed method allows patient dose and image noise to be controlled in such a way that dose reduction does not impair the detection of low-contrast lesions. The proposed values correspond to high- quality images and can be reduced if only high-contrast organs are assessed.

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Audit report on the Iowa Department of Human Services – Case Management Unit for the year ended June 30, 2007

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Many multivariate methods that are apparently distinct can be linked by introducing oneor more parameters in their definition. Methods that can be linked in this way arecorrespondence analysis, unweighted or weighted logratio analysis (the latter alsoknown as "spectral mapping"), nonsymmetric correspondence analysis, principalcomponent analysis (with and without logarithmic transformation of the data) andmultidimensional scaling. In this presentation I will show how several of thesemethods, which are frequently used in compositional data analysis, may be linkedthrough parametrizations such as power transformations, linear transformations andconvex linear combinations. Since the methods of interest here all lead to visual mapsof data, a "movie" can be made where where the linking parameter is allowed to vary insmall steps: the results are recalculated "frame by frame" and one can see the smoothchange from one method to another. Several of these "movies" will be shown, giving adeeper insight into the similarities and differences between these methods.

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The jointly voluntary and involuntary control of respiration, unique among essential physiological processes, the interconnection of breathing with and its influence on the autonomic nervous system, and disease states associated with the interface between psychology and respiration (e.g., anxiety disorders, hyperventilation syndrome, asthma) make the study of the relationship between respiration and emotion both theoretically and clinically of great relevance. However, the respiratory behavior during affective states is not yet completely understood. We studied breathing pattern responses to 13 picture series varying widely in their affective tone in 37 adults (18 men, 19 women, mean age 26). Time and volume parameters were recorded with the LifeShirt system (VivoMetrics Inc., Ventura, California, USA, see image). We also measured end-tidal pCO2 (EtCO2) with a Microcap Handheld Capnograph (Oridion Medical 1987 Ltd., Jerusalem, Israel) to determine if ventilation is in balance with metabolic demands and spontaneous eye-blinking to investigate the link between respiration and attention. At the end of each picture series, the participants reported their subjective feeling in the affective dimensions of pleasantness and arousal. Increasing self-rated arousal was associated with increasing minute ventilation but not with decreases in EtCO2, suggesting that ventilatory changes during picture viewing paralleled variations in metabolic activity. EtCO2 correlated with pleasantness, and eye-blink rate decreased with increasing unpleasantness in line with a negativity bias in attention. Like MV, inspiratory drive (i.e., mean inspiratory flow) increased with arousal. This relationship reflected increases in inspiratory volume rather than shortening of the time parameters. This study confirms that respiratory responses to affective stimuli are organized to a certain degree along the dimensions of pleasantness and arousal. It shows, for the first time, that during picture viewing, ventilatory increases with increasing arousal are in balance with metabolic activity and that inspiratory volume is modulated by arousal. MV emerges as the most reliable respiratory index of self-perceived arousal. Finally, end-tidal pCO2 is slightly lower during processing of negative as compared to positive picture contents, which is proposed to enhance sensory perception and reflect a negativity bias in attention.

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OBJECTIVES: To provide a global, up-to-date picture of the prevalence, treatment, and outcomes of Candida bloodstream infections in intensive care unit patients and compare Candida with bacterial bloodstream infection. DESIGN: A retrospective analysis of the Extended Prevalence of Infection in the ICU Study (EPIC II). Demographic, physiological, infection-related and therapeutic data were collected. Patients were grouped as having Candida, Gram-positive, Gram-negative, and combined Candida/bacterial bloodstream infection. Outcome data were assessed at intensive care unit and hospital discharge. SETTING: EPIC II included 1265 intensive care units in 76 countries. PATIENTS: Patients in participating intensive care units on study day. INTERVENTIONS: None. MEASUREMENT AND MAIN RESULTS: Of the 14,414 patients in EPIC II, 99 patients had Candida bloodstream infections for a prevalence of 6.9 per 1000 patients. Sixty-one patients had candidemia alone and 38 patients had combined bloodstream infections. Candida albicans (n = 70) was the predominant species. Primary therapy included monotherapy with fluconazole (n = 39), caspofungin (n = 16), and a polyene-based product (n = 12). Combination therapy was infrequently used (n = 10). Compared with patients with Gram-positive (n = 420) and Gram-negative (n = 264) bloodstream infections, patients with candidemia were more likely to have solid tumors (p < .05) and appeared to have been in an intensive care unit longer (14 days [range, 5-25 days], 8 days [range, 3-20 days], and 10 days [range, 2-23 days], respectively), but this difference was not statistically significant. Severity of illness and organ dysfunction scores were similar between groups. Patients with Candida bloodstream infections, compared with patients with Gram-positive and Gram-negative bloodstream infections, had the greatest crude intensive care unit mortality rates (42.6%, 25.3%, and 29.1%, respectively) and longer intensive care unit lengths of stay (median [interquartile range]) (33 days [18-44], 20 days [9-43], and 21 days [8-46], respectively); however, these differences were not statistically significant. CONCLUSION: Candidemia remains a significant problem in intensive care units patients. In the EPIC II population, Candida albicans was the most common organism and fluconazole remained the predominant antifungal agent used. Candida bloodstream infections are associated with high intensive care unit and hospital mortality rates and resource use.

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Maturation of the arenavirus GP precursor (GPC) involves proteolytic processing by cellular signal peptidase and the proprotein convertase subtilisin kexin isozyme 1 (SKI-1)/site 1 protease (S1P), yielding a tripartite complex comprised of a stable signal peptide (SSP), the receptor-binding GP1, and the fusion-active transmembrane GP2. Here we investigated the roles of SKI-1/S1P processing and SSP in the biosynthesis of the recombinant GP ectodomains of lymphocytic choriomeningitis virus (LCMV) and Lassa virus (LASV). When expressed in mammalian cells, the LCMV and LASV GP ectodomains underwent processing by SKI-1/S1P, followed by dissociation of GP1 from GP2. The GP2 ectodomain spontaneously formed trimers as revealed by chemical cross-linking. The endogenous SSP, known to be crucial for maturation and transport of full-length arenavirus GPC was dispensable for processing and secretion of the soluble GP ectodomain, suggesting a specific role of SSP in the stable prefusion conformation and transport of full-length GPC.

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Cobalt-labelled motoneuron dendrites of the frog spinal cord at the level of the second spinal nerve were photographed in the electron microscope from long series of ultrathin sections. Three-dimensional computer reconstructions of 120 dendrite segments were analysed. The samples were taken from two locations: proximal to cell body and distal, as defined in a transverse plane of the spinal cord. The dendrites showed highly irregular outlines with many 1-2 microns-long 'thorns' (on average 8.5 thorns per 100 microns 2 of dendritic area). Taken together, the reconstructed dendrite segments from the proximal sites had a total length of about 250 microns; those from the distal locations, 180 microns. On all segments together there were 699 synapses. Nine percent of the synapses were on thorns, and many more close to their base on the dendritic shaft. The synapses were classified in four groups. One third of the synapses were asymmetric with spherical vesicles; one half were symmetric with spherical vesicles; and one tenth were symmetric with flattened vesicles. A fourth, small class of asymmetric synapses had dense-core vesicles. The area of the active zones was large for the asymmetric synapses (median value 0.20 microns 2), and small for the symmetric ones (median value 0.10 microns 2), and the difference was significant. On average, the areas of the active zones of the synapses on thin dendrites were larger than those of synapses on large calibre dendrites. About every 4 microns 2 of dendritic area received one contact. There was a significant difference between the areas of the active zones of the synapses at the two locations. Moreover, the number per unit dendritic length was correlated with dendrite calibre. On average, the active zones covered more than 4% of the dendritic area; this value for thin dendrites was about twice as large as that of large calibre dendrites. We suggest that the larger active zones and the larger synaptic coverage of the thin dendrites compensate for the longer electrotonic distance of these synapses from the soma.

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Critical illness is characterised by nutritional and metabolic disorders, resulting in increased muscle catabolism, fat-free mass loss, and hyperglycaemia. The objective of the nutritional support is to limit fat-free mass loss, which has negative consequences on clinical outcome and recovery. Early enteral nutrition is recommended by current guidelines as the first choice feeding route in ICU patients. However, enteral nutrition alone is frequently associated with insufficient coverage of the energy requirements, and subsequently energy deficit is correlated to worsened clinical outcome. Controlled trials have demonstrated that, in case of failure or contraindications to full enteral nutrition, parenteral nutrition administration on top of insufficient enteral nutrition within the first four days after admission could improve the clinical outcome, and may attenuate fat-free mass loss. Parenteral nutrition is cautious if all-in-one solutions are used, glycaemia controlled, and overnutrition avoided. Conversely, the systematic use of parenteral nutrition in the ICU patients without clear indication is not recommended during the first 48 hours. Specific methods, such as thigh ultra-sound imaging, 3rd lumbar vertebra-targeted computerised tomography and bioimpedance electrical analysis, may be helpful in the future to monitor fat-free mass during the ICU stay. Clinical studies are warranted to demonstrate whether an optimal nutritional management during the ICU stay promotes muscle mass and function, the recovery after critical illness and reduces the overall costs.

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Biosynthesis of active endothelin-1 (ET-1) implies an enzymatic processing of the inactive precursor Big ET-1 (1-39) into the mature, 21 amino acid peptide. The aim of this study was to characterize in airway and alveolar epithelial cells the enzymes responsible for this activation. BEAS-2B and A549 cells, which both produce ET-1, were studied in vitro as models for bronchiolar and alveolar cells, respectively. Both cell lines were able to convert exogenously added Big ET-1 (0.1 microM) into ET-1, suggesting a cell surface or an extracellular processing. The conversion was inhibited by phosphoramidon in both cell lines with an IC50 approximately 1 microM, but not by thiorphan, a specific inhibitor of neutral endopeptidase 24.11 (NEP). The endogenous production of serum-stimulated BEAS-2B and A549 cells was not inhibited by thiorphan, and phosphoramidon showed inhibition only at high concentration (>100 microM). Western blotting following electrophoresis in reducing conditions demonstrated a protein of MR 110 corresponding to the ECE-1 monomer in both BEAS-2B and A549 cells, as well as in whole lung extracts. By RT-PCR we revealed the mRNA encoding for the ECE-1b and/or -1c subtype, but not ECE-1a, in both cell lines. We conclude that BEAS-2B and A549 cells are able to process either endogenous or exogenous Big ET-1 by ECE-1 and that isoforms 1b and 1c could be involved in this processing with no significant role of NEP.

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Cet article décrit les procédures de soins mises en place depuis 10 ans au Centre de jeu excessif à Lausanne pour intégrer les proches dans le traitement des addictions aux jeux d'argent. Ce bilan permet de dégager également des pistes pour améliorer cette prise en compte des proches, que ce soit au niveau de la formation ou au niveau politique. (réd.).

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Iowa Grain Facilities Map