809 resultados para 887


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Collagen, the main structural component of the extracellular matrix (ECM), provides tensile stiffness to different structures and organs against rupture. However, collagen tissue-engineered implants are hereto still lacking in mechanical strength. Attempts to create stiffer scaffolds have resulted in increased brittleness of the material, reducing the versatility of the original component. The hypothesis behind this research is that the introduction of an elastic element in the scaffold will enhance the mechanical properties of the collagen-based scaffolds, as elastin does in the ECM to prevent irreversible deformation. In this study, an elastin-like polymer (ELP) designed and synthesized using recombinant DNA methodology is used with the view to providing increased proteolytic resistance and increased functionality to the scaffolds by carrying specific sequences for microbial transglutaminase cross-linking, endothelial cell adhesion, and drug delivery. Evaluation of the effects that cross-linking ELP-collagen has on the physicochemical properties of the scaffold such as porosity, presence of cross-linking, thermal behavior, and mechanical strength demonstrated that the introduction of enzymatically resistant covalent bonds between collagen and ELP increases the mechanical strength of the scaffolds in a dose-dependent manner without significantly affecting the porosity or thermal properties of the original scaffold. Importantly, the scaffolds also showed selective behavior, in a dose (ELP)-dependent manner toward human umbilical vein endothelial cells and smooth muscle cells when compared to fibroblasts.

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Studies of spatial summation often use sinusoidal gratings with blurred edges. When the envelope is elongated (i) along the grating stripes and (ii) at right angles to the grating stripes, we refer to the stimuli as skunk-tails and tiger-tails respectively. Previous work [Polat & Tyler, 1999; Vision Research, 39, 887-895.] has found that sensitivity to skunk-tails is greater than for tiger-tails, but there have been several failures to replicate this result within a subset of the conditions. To address this we measured detection thresholds for skunk-tails, tiger-tails and squares of grating with sides matched to the lengths of the tails. For foveal viewing, we found a contrast sensitivity advantage in the order of 2 dB for skunk-tails over tiger-tails, but only for horizontal gratings. For vertical gratings, sensitivity was very similar for both tail-types. When the stimuli were presented parafoveally (upper right visual field), a small advantage was found for skunk-tails over tiger-tails at both orientations, and spatial summation slopes were close to that of the ideal observer. We did not replicate the findings of Polat & Tyler, but our results are consistent with (i) those of Foley et al. [Foley, J. M., Varadharajan, S., Koh, C. C., & Farias, C. Q. (2007) Vision Research, 47, 85-107.] who used only vertical gratings and (ii) those from modelfest, where only horizontal gratings were used. The small effect of tail-type here suggests an anisotropy in the underlying physiology. © 2007 Elsevier Ltd. All rights reserved.

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The problem of learning by examples in ultrametric committee machines (UCMs) is studied within the framework of statistical mechanics. Using the replica formalism we calculate the average generalization error in UCMs with L hidden layers and for a large enough number of units. In most of the regimes studied we find that the generalization error, as a function of the number of examples presented, develops a discontinuous drop at a critical value of the load parameter. We also find that when L>1 a number of teacher networks with the same number of hidden layers and different overlaps induce learning processes with the same critical points.

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Purpose: Evaluating the impact of splitting toric power on patient tolerance to misorientation such as with intraocular lens rotation. Setting: University vision clinic. Methods: Healthy, non astigmats had +1.50D astigmatism induced with spectacle lenses at 90°, 135°, 180° and +3.00D at 90°. Two correcting cylindrical lenses of the opposite sign and half the power each were subsequently added to the trial frame misaligned by 0°, 5° or 10° in a random order and misorientated from the initial axis in a clockwise direction by up to 15° in 5° steps. A second group of adapted astigmats with between 1.00 and 3.00DC had their astigmatism corrected with two toric spectacle lenses of half the power separated by 0°, 5° or 10° and misorientated from the initial axis in both directions by up to 15° in 5° steps. Distance, high contrast visual acuity was measured using a computerised test chart at each lens misalignment and misorientation. Results: Misorientation of the split toric lenses caused a statistically significant drop in visual acuity (F= 70.341; p< 0.001). Comparatively better acuities were observed around 180°, as anticipated (F= 3.775; p= 0.035). Misaligning the split toric power produced no benefit in visual acuity retention with axis misorientation when subjects had astigmatism induced with a low (F= 2.190, p= 0.129) or high cylinder (F= 0.491, p= 0.617) or in the adapted astigmats (F= 0.120, p= 0.887). Conclusion: Misalignment of toric lens power split across the front and back lens surfaces had no beneficial effect on distance visual acuity, but also no negative effect. © 2013 British Contact Lens Association.

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Similar to classic Signal Detection Theory (SDT), recent optimal Binary Signal Detection Theory (BSDT) and based on it Neural Network Assembly Memory Model (NNAMM) can successfully reproduce Receiver Operating Characteristic (ROC) curves although BSDT/NNAMM parameters (intensity of cue and neuron threshold) and classic SDT parameters (perception distance and response bias) are essentially different. In present work BSDT/NNAMM optimal likelihood and posterior probabilities are analytically analyzed and used to generate ROCs and modified (posterior) mROCs, optimal overall likelihood and posterior. It is shown that for the description of basic discrimination experiments in psychophysics within the BSDT a ‘neural space’ can be introduced where sensory stimuli as neural codes are represented and decision processes are defined, the BSDT’s isobias curves can simultaneously be interpreted as universal psychometric functions satisfying the Neyman-Pearson objective, the just noticeable difference (jnd) can be defined and interpreted as an atom of experience, and near-neutral values of biases are observers’ natural choice. The uniformity or no-priming hypotheses, concerning the ‘in-mind’ distribution of false-alarm probabilities during ROC or overall probability estimations, is introduced. The BSDT’s and classic SDT’s sensitivity, bias, their ROC and decision spaces are compared.

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A tanulmány a szakirodalomban újszerű kezdeményezésként kísérletet tesz a gabonapiac ellátási láncának felrajzolására, majd annak egyik, a cikk alapkérdése szempontjából kiemelt vetületét, a gabonaszállítási és raktározási problémákat elemzi. Előbbit a piac szereplőitől kvalitatív módon begyűjtött információkkal, utóbbit a szakirodalom alapján mutatja be. A cikk az elemzés után javaslatokkal szolgál ahhoz, hogyan lehetne hazánkban egy integrált gabonapiaci szállítási-raktározási-átrakási rendszert kialakítani. __________ The aim of the article is to present the situation of the Hungarian cereals transport and storage-reloading market and by interconnection, to treat cereals market’s operations systemically. Under this process, the study trace to draw a possible supply chain of the national cereals market up, which is a new initiation in the Hungarian literature. The focus of the article is to analyse transport and storage processes in the cereals market using the framework mentioned above. Transport market is demonstrated on the grounds of a revealing qualitative research, while storage market is brought out by literature. After analysis, the article gives recommendations how to shape an integrated transport and storage-reload system in the Hungarian cereals market.

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Leishmaniasis is one of the most important emerging vector-borne diseases in Western Eurasia. Although winter minimum temperatures limit the present geographical distribution of the vector Phlebotomus species, the heat island effect of the cities and the anthropogenic heat emission together may provide the appropriate environment for the overwintering of sand flies. We studied the climate tempering effect of thermal bridges and the heat island effect in Budapest, Hungary. Thermal imaging was used to measure the heat surplus of heat bridges. The winter heat island effect of the city was evaluated by numerical analysis of the measurements of the Aqua sensor of satellite Terra. We found that the surface temperature of thermal bridges can be at least 3-7 °C higher than the surrounding environment. The heat emission of thermal bridges and the urban heat island effect together can cause at least 10 °C higher minimum ambient temperature in winter nights than the minimum temperature of the peri-urban areas. This milder micro-climate of the built environment can enable the potential overwintering of some important European Phlebotomus species. The anthropogenic heat emission of big cities may explain the observed isolated northward populations of Phlebotomus ariasi in Paris and Phlebotomus neglectus in the agglomeration of Budapest.

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Bob del Toro, Dianne Haley and Others with Toys for Managuan Relief. On December 23, 12:29 a.m. local time in Managua, Nicaragua, a magnitude 6.2 earthquake occurred. The earth caused widespread damage among Managua, the capital city. In Managua, 5,000 residents were killed, 20,000 were injured and over 250,000 were left homeless. In Miami, residents and relief organizations focused on helping children. Wife of General Arturo Somoza pleaded on efforts on gathering sporting goods and toys for Managua’s young people. Relief committees purchased 230 dozen balls – basketball, rubber, and volley, soccer, and others. Nearly $500 came from students in Hialeah High School. Jump ropes and jacks were donated from a sorority at Florida International University. Arrangements were made to bring 44,000 pounds of baby formula and canned meat and 13,000 pounds of medicine. Many of Miami’s corporations, associations, and residents contributed to the Managuan Relief effort. Source: The Miami News, March 19, 1973 by Lynn Feigenbaum 887-3400. april 30, 1973. Cutlines: More than 350 dozens of various balls, skate boards and games were recently purchased by the Student Governance Committee of Florida International University for the young people of Managua, Nicaragua who not only do not have enough toys but are unable to attend schools which are closed. Left to right are, Bob del Toro, Dianne Haley, Chairman of the Student Governance Committee, Hialeah Councilman Jack Weaver of the Hialeah-Managua Sister City Committee, Barbara O'Nan and Margaret Klein.

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On December 23, 12:29 a.m. local time in Managua, Nicaragua, a magnitude 6.2 earthquake occurred. The earth caused widespread damage among Managua, the capital city. In Managua, 5,000 residents were killed, 20,000 were injured and over 250,000 were left homeless. In Miami, residents and relief organizations focused on helping children. Wife of General Arturo Somoza pleaded on efforts on gathering sporting goods and toys for Managua’s young people. Relief committees purchased 230 dozen balls – basketball, rubber, and volley, soccer, and others. Nearly $500 came from students in Hialeah High School. Jump ropes and jacks were donated from a sorority at Florida International University. Arrangements were made to bring 44,000 pounds of baby formula and canned meat and 13,000 pounds of medicine. Many of Miami’s corporations, associations, and residents contributed to the Managuan Relief effort. Source: The Miami News, March 19, 1973 by Lynn Feigenbaum From: City of Hialeah Publicity Bureu. 401 1/2 East 1st Ave. Hialeah, Fla. 887-3400. april 30, 1973. Cutlines: Florida International University students recently raised more than $ 1,000 for more than 300 dozens toys and balls for the youngsters of Managua, Nicaragua. With the balls above are shown student Committee members and oficials of the Hialeah-Managua Sister City Committee, left to rigth: Bob del Toro, Sister City Committe president Raymond R. Schultz, Student Governance Committee chairman Dianne Haley and Hialeah City councilman Jack Weaver.

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On December 23, 12:29 a.m. local time in Managua, Nicaragua, a magnitude 6.2 earthquake occurred. The earth caused widespread damage among Managua, the capital city. In Managua, 5,000 residents were killed, 20,000 were injured and over 250,000 were left homeless. In Miami, residents and relief organizations focused on helping children. Wife of General Arturo Somoza pleaded on efforts on gathering sporting goods and toys for Managua’s young people. Relief committees purchased 230 dozen balls – basketball, rubber, and volley, soccer, and others. Nearly $500 came from students in Hialeah High School. Jump ropes and jacks were donated from a sorority at Florida International University. Arrangements by organizations were made to bring 44,000 pounds of baby formula and canned meat and 13,000 pounds of medicine. Many of Miami’s corporations, associations, and residents contributed to the Managuan Relief effort. Source: The Miami News, March 19, 1973 by Lynn Feigenbaum From: City of Hialeah Publicity Bureu. 401 1/2 East 1st Ave. Hialeah, Fla. 887-3400. april 30, 1973. Cutlines: Skate boards, paddle balls and flying saucers were among the big shipment of toys which was recently dispatched to Managua, Nicaragua by students of Florida International University through the Hialeah-Managua Sister Committee. Examining the toys above are, left to right: Margaret Klein, Hialeah councilman Jack Weaver and Barbara O'Nan.

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This dataset contains the collection of available published paired Uk'37 and Tex86 records spanning multi-millennial to multi-million year time scales, as well as a collection of Mg/Ca-derived temperatures measured in parallel on surface and subsurface dwelling foraminifera, both used in the analyses of Ho and Laepple, Nature Geoscience 2016. As the signal-to-noise ratios of proxy-derived Holocene temperatures are relatively low, we selected records that contain at least the last deglaciation (oldest sample >18kyr BP).

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The Tara Oceans Expedition (2009-2013) sampled the world oceans on board a 36 m long schooner, collecting environmental data and organisms from viruses to planktonic metazoans for later analyses using modern sequencing and state-of-the-art imaging technologies. Tara Oceans Data are particularly suited to study the genetic, morphological and functional diversity of plankton. The present data set includes properties of seawater, particulate matter and dissolved matter from physical, optical and imaging sensors mounted on a vertical sampling system (Rosette) used during the 2009-2013 tara Oceans Expedition. It comprised 2 pairs of conductivity and temperature sensors (SEABIRD components), and a complete set of WEtLabs optical sensors, including chrorophyll and CDOM fluorometers, a 25 cm transmissiometer, and a one-wavelength backscatter meter. In addition, a SATLANTIC ISUS nitrate sensor and a Hydroptic Underwater Vision Profiler (UVP) were mounted on the rosette. In the Arctic Ocean and Arctic Seas (2013), a second oxygen sensor (SBE43) and a four frequency Aquascat acoustic profiler were added. The system was powered on specific Li-Ion batteries and data were self-recorded at 24HZ. Sensors have all been factory calibrated before, during and after the four year program. Oxygen was validated using climatologies (WOA09). Nitrate and Fluorescence data were adjusted with discrete measurements from Niskin bottles mounted on the Rosette, and optical darks were performed monthly on board. A total of 839 quality checked vertical profiles were made during the tara Oceans expedition 2009-2013.

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Wind- induced exposure is one of the major forces shaping the geomorphology and biota in coastal areas. The effect of wave exposure on littoral biota is well known in marine environments (Ekebon et al., 2003; Burrows et al., 2008). In the Cabrera Archipelago National Park wave exposure has demostrated to have an effect on the spatial distribution of different stages of E.marginatus (Alvarez et al., 2010). Standarized average wave exposures during 2008 along the Cabrera Archipelago National park coast line were calculated to be applied in studies of littoral species distribution within the archipelago. Average wave exposure (or apparent wave power) was calculated for points located 50 m equidistant on the coastline following the EXA methodology (EXposure estimates for fragmented Archipelagos) (Ekebon et al., 2003). The average wave exposures were standardized from 1 to 100 (minimum and maximum in the area), showing coastal areas with different levels of mea wave exposure during the year. Input wind data (direction and intensity) from 2008 was registered at the Cabrera mooring located north of Cabrera Archipelago. Data were provided by IMEDEA (CSIC-UIB, TMMOS http://www.imedea.uib-csic.es/tmoos/boyas/). This cartography has been developed under the framework of the project EPIMHAR, funded by the National Park's Network (Spanish Ministry of Environment, Maritime and Rural Affairs, reference: 012/2007 ). Part of this work has been developed under the research programs funded by "Fons de Garantia Agrària i Pesquera de les Illes Balears (FOGAIBA)".

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