878 resultados para Wolan, Andrzej, 1530-1616.
Resumo:
The aim of this study was to verify and describe the presence of microorganisms in the single-use trocar after its use in surgical procedures, and after this device was submitted to cleaning, conditioning, and sterilization by physicochemical processes (formaldehyde, ethylene oxide, and hydrogen peroxide plasma). Twenty-eight trocars of the Ethicon, Auto-suture, and Aesculap brands, were randomly selected and analyzed after laparoscopic cholecystectomy. The results have shown that cultures grown of the material collected from the trocars, immediately after its use and before its sterilization process, showed the presence of bacteria and fungi in 46.5% (13). In 53.5% (15) of the trocars, the presence of microorganisms was not detected, very likely due to niche`s scarcity. In the cultures grown of the 28 trocars after being submitted to sterilization processes, the presence of microorganisms was not verified. We can therefore conclude that although trocars possess compartments not easily accessed for cleaning, these devices can be adequately cleaned and effectively sterilized, when well manipulated, in the institution where the study was carried out by the processes of steam sterilization at low temperature and formaldehyde, ethylene oxide, and hydrogen peroxide plasma.
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Endurance exercise is known to enhance peripheral insulin sensitivity and reduce insulin secretion. However, it is unknown whether the latter effect is due to the reduction in plasma substrate availability or alterations in beta-cell secretory machinery. Here, we tested the hypothesis that endurance exercise reduces insulin secretion by altering the intracellular energy-sensitive AMP-activated kinase (AMPK) signaling pathway. Male Wistar rats were submitted to endurance protocol training one, three, or five times per week, over 8 weeks. After that, pancreatic islets were isolated, and glucose-induced insulin secretion (GIIS), glucose transporter 2 (GLUT2) protein content, total and phosphorylated calmodulin kinase kinase (CaMKII), and AMPK levels as well as peroxisome proliferator-activated receptor-gamma coactivator-1-alpha (PGC-1 alpha) and uncoupling protein 2 (UCP2) content were measured. After 8 weeks, chronic endurance exercise reduced GIIS in a dose-response manner proportionally to weekly exercise frequency. Contrariwise, increases in GLUT2 protein content, CaMKII and AMPK phosphorylation levels were observed. These alterations were accompanied by an increase in UCP2 content, probably mediated by an enhancement in PGC-1 alpha protein expression. In conclusion, chronic endurance exercise induces adaptations in beta-cells leading to a reduction in GIIS, probably by activating the AMPK signaling pathway. Journal of Endocrinology (2011) 208, 257-264
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Visualization of high-dimensional data requires a mapping to a visual space. Whenever the goal is to preserve similarity relations a frequent strategy is to use 2D projections, which afford intuitive interactive exploration, e. g., by users locating and selecting groups and gradually drilling down to individual objects. In this paper, we propose a framework for projecting high-dimensional data to 3D visual spaces, based on a generalization of the Least-Square Projection (LSP). We compare projections to 2D and 3D visual spaces both quantitatively and through a user study considering certain exploration tasks. The quantitative analysis confirms that 3D projections outperform 2D projections in terms of precision. The user study indicates that certain tasks can be more reliably and confidently answered with 3D projections. Nonetheless, as 3D projections are displayed on 2D screens, interaction is more difficult. Therefore, we incorporate suitable interaction functionalities into a framework that supports 3D transformations, predefined optimal 2D views, coordinated 2D and 3D views, and hierarchical 3D cluster definition and exploration. For visually encoding data clusters in a 3D setup, we employ color coding of projected data points as well as four types of surface renderings. A second user study evaluates the suitability of these visual encodings. Several examples illustrate the framework`s applicability for both visual exploration of multidimensional abstract (non-spatial) data as well as the feature space of multi-variate spatial data.
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The presence of certain kinds of defects at the edges of monohydrogenated zigzag graphene nanoribbons changes dramatically the charge transport properties inducing a spin-polarized conductance. Using an approach based on density functional theory and nonequilibrium Green`s function formalism to calculate the transmittance, we classify the defects in different classes depending on their distinct transport properties: (i) sigma-defects, which do not affect the transmittance close to the Fermi energy (E(F)); and (ii) pi-defects, which cause a spin polarization of the transmittance and that can be further divided into either electron or hole defects if the spin transport polarization results in larger transmittance for the up or down spin channel, respectively.
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Several experimental groups have achieved effective n- and p-type doping of silicon nanowires (SiNWs). However, theoretical analyses on ultrathin SiNWs suggest that dopants tend to segregate to their surfaces, where they would combine with defects such as dangling bonds (DB), becoming electronically inactive. Using fully ab initio calculations, we show that the differences in formation energies among surface and core substitutional sites decrease rapidly as the diameters of the wires increase, indicating that the dopants will be uniformly distributed. Moreover, occurrence of the electronically inactive impurity/DB complex rapidly becomes less frequent for NWs of larger diameters. We also show that the high confinement in the ultrathin SiNWs causes the impurity levels to be deeper than in the silicon bulk, but our results indicate that for NWs of diameters larger than approximately 3 nm the impurity levels recover bulk characteristics. Finally, we show that different surfaces will lead to different dopant properties in the gap.
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Low-frequency noise in an electrolyte-insulator- semiconductor (EIS) structure functionalized with multilayers of polyamidoamine (PAMAM) dendrimer and single-walled carbon nanotubes (SWNT) is studied. The noise spectral density exhibits 1/f(gamma) dependence with the power factor of gamma approximate to 0.8 and gamma = 0.8-1.8 for the bare and functionalized EIS sensor, respectively. The gate-voltage noise spectral density is practically independent of the pH value of the solution and increases with increasing gate voltage or gate-leakage current. It has been revealed that functionalization of an EIS structure with a PAMAM/SWNTs multilayer leads to an essential reduction of the 1/f noise. To interpret the noise behavior in bare and functionalized EIS devices, a gate-current noise model for capacitive EIS structures based on an equivalent flatband-voltage fluctuation concept has been developed.
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The Capivarita Anorthosite, formed in an intraplate environment and later metamorphosed under amphibolites fades conditions, is exposed in the Dom Feliciano Belt as part of the Brasiliano magmatic arc and occurs as a roof-pedant in, or is even intruded by, 0.6 Ga post-collisional granites. In this work, magmatic and metamorphic minerals were dated using the LA-MC-ICP-MS in situ method. U-Pb magmatic and metamorphic zircon dating yielded an age of 1573 +/- 21 Ma and of 606 +/- 6 Ma, respectively, whereas the igneous titanite dating yielded an age of 1530 +/- 33 Ma and the metamorphic ages were 651 +/- 9 Ma and 601 +/- 5 Ma. The Lu-Hf model ages showed two clusters from 1.81 to 2.03 Ga (calf from +2.21 to +6.42) and 2.55-2.62 Ga (epsilon epsilon Hf from -4.59 to -5.64). This intraplate magmatism can be connected to a very important episode of continental accretion in an extensional setting from the fragmentation of the supercontinent during the Early Mesoproterozoic. (C) 2011 Elsevier B.V. All rights reserved.
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The ionic liquid (IL), 1-allyl-3-(1-butyl)imidazolium chloride (AlBuImCl), has been synthesized and its properties determined. Increase in the temperature increased its conductivity and decreased its density, polarity, and viscosity. Microcrystalline cellulose (MCC), dissolves in thisIL by heating at 80 degrees C; this did not affect its degree of polymerization, decreased its index of crystallinity (Ic), and changed in morphology after regeneration. Convenient acylation of MCC was achieved by using 50% excess anhydride at 80 degrees C, for 24 or 48 h for acetic and butyric anhydride, respectively. The composition of the mixed esters depended on the initial ratio of the anhydrides, and their order of addition.
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Syftet med detta examensarbete har varit mångfacetterat. Vi har undersökt om hur eleverna upplever det informella inflytandet över utbildningen på sina program, generellt sett och i samhällskunskap A. I detta har vi även undersökt skillnader mellan mäns och kvinnors uppfattning av inflytande i detta. Vidare har vi undersökt om eleverna ansett sig ha elevinflytande, och om de är nöjda med inflytandet på sin utbildning. Slutligen är syftet att skapa en modell för utvärdering av elevinflytande.Undersökningen är baserad på en enkätundersökning, som vi har genomfört på fyra program, på en gymnasieskola i Mellansverige. Programmen har varit El-, Handels, Medie- och samhällsprogrammet. Vi har avgränsat oss till det så kallade informella inflytandet, som har att göra med elevens inflytande över undervisningen, genom till exempel planering, genomförande och utvärdering. I vår undersökning har vi undersökt kategorierna: Innehåll i undervisningen, arbetsform, läromedel samt examinationssätt.Undersökningen påvisar att eleverna, i majoritet, anser att de har inflytande över sin utbildning. Vidare så anser en majoritet av eleverna, utom i Handelsprogrammet, att de är nöjda med inflytandet på utbildningen. Vi har dock kommit fram till att eleverna, generellt sett på utbildningen, upplever att det informella inflytandet är svagt och/eller gränsande mot mycket svagt informellt inflytande, i de olika kategorier som vi undersökt. Resultatet visar också, angående kursen samhällskunskap A, även där är svagt och/eller mycket svagt gällande det informella inflytandet, i de olika kategorier som vi undersökt.Vidare så har kommit fram till att det finns ett genusperspektiv, gällande det informella elevinflytandet. Skillnaderna mellan könen är att männen anser sig ha mest att säga till om gällande arbetsform och läromedel och minst om examinationssätt och innehåll i undersvingen, generellt sett på programmen. Medans kvinnorna enbart anser att de har mest inflytande över läromedel och minst över innehållet i undervisningen, generellt sett på programmen. Gällande samhällskunskap A, så anser männen att de har mest inflytande över arbetsform, och minst över examinationssätt. Medans kvinnorna ansett sig ha mest över innehåll i undervisningen och minst över examinationssätt. Männen och kvinnorna har dock den likheten, att de i samtliga kategorier anser att elevernas upplevelse av det informella inflytandet, är att det både generellt sett och i kursen samhällskunskap A är svagt och/eller mycket svagt.
New Resource Augmentation Analysis of the Total Stretch of SRPT and SJF in Multiprocessor Scheduling
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My research aims to understand how and why fundamentalists justify violence against people who do not fit their profile of "righteous" or "saved" persons, such as abortion doctors and clinic workers, gays and lesbians, and Jews. The first section of this paper travels through the history of fundamentalism since its origins in the British and American apocalipticism, or belief in the Second Coming of Jesus Christ. However, my history of Protestant Fundamentalism in the United States will focus on the ways in which Fundamentalism developed in response to many changes in American social structure. I interpret Fundamentalism as an anti-modern movement seeking to reassert "traditional" Christian values.