796 resultados para 833


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Background Emotional-processing inhibition has been suggested as a mechanism underlying some of the clinical features of depersonalization and/or derealization. In this study, we tested the prediction that autonomic response to emotional stimuli would be reduced in patients with depersonalization disorder. Methods The skin conductance responses of 15 patients with chronic depersonalization disorder according to DSM-IV, 15 controls, and 11 individuals with anxiety disorders according to DSM-IV, were recorded in response to nonspecific elicitors (an unexpected clap and taking a sigh) and in response to 15 randomized pictures with different emotional valences: 5 unpleasant, 5 pleasant, and 5 neutral. Results The skin conductance response to unpleasant pictures was significantly reduced in patients with depersonalization disorder (magnitude of 0.017 µsiemens in controls and 0.103 µsiemens in patients with anxiety disorders; P = .01). Also, the latency of response to these stimuli was significantly prolonged in the group with depersonalization disorder (3.01 seconds compared with 2.5 and 2.1 seconds in the control and anxiety groups, respectively; P = .02). In contrast, latency to nonspecific stimuli (clap and sigh) was significantly shorter in the depersonalization and anxiety groups (1.6 seconds) than in controls (2.3 seconds) (P = .03). Conclusions In depersonalization disorder, autonomic response to unpleasant stimuli is reduced. The fact that patients with depersonalization disorder respond earlier to a startling noise suggests that they are in a heightened state of alertness and that the reduced response to unpleasant stimuli is caused by a selective inhibitory mechanism on emotional processing.

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Future optical networks will require the implementation of very high capacity (and therefore spectral efficient) technologies. Multi-carrier systems, such as Orthogonal Frequency Division Multiplexing (OFDM) and Coherent WDM (CoWDM), are promising candidates. In this paper, we present analytical, numerical, and experimental investigations of the impact of the relative phases between optical subcarriers of CoWDM systems, as well as the effect that the number of independently modulated subcarriers can have on the performance. We numerically demonstrate a five-subcarrier and three-subcarrier 10-GBd CoWDM system with direct detected amplitude shift keying (ASK) and differentially/coherently detected (D) phase shift keying (PSK). The simulation results are compared with experimental measurements of a 32-Gbit/s DPSK CoWDM system in two configurations. The first configuration was a practical 3-modulator array where all three subcarriers were independently modulated, the second configuration being a traditional 2-modulator odd/even configuration, where only odd and even subcarriers were independently modulated. Simulation and experimental results both indicate that the independent modulation implementation has a greater dependency on the relative phases between subcarriers, with a stronger penalty for the center subcarrier than the odd/even modulation scheme.

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An enhanced tonic GABA-A inhibition in the thalamus plays a crucial role in experimental absence seizures, and has been attributed, on the basis of indirect evidence, to a dysfunction of the astrocytic GABA transporter-1 (GAT-1). Here, the GABA transporter current was directly investigated in thalamic astrocytes from a well-established genetic model of absence seizures, the Genetic Absence Epilepsy Rats from Strasbourg (GAERS), and its non-epileptic control (NEC) strain. We also characterized the novel form of GABAergic and glutamatergic astrocyte-to-neuron signalling by recording slow outward currents (SOCs) and slow inward currents (SICs), respectively, in thalamocortical (TC) neurons of both strains. In patch-clamped astrocytes, the GABA transporter current was abolished by combined application of the selective GAT-1 and GAT-3 blocker, NO711 (30µM) and SNAP5114 (60µM), respectively, to GAERS and NEC thalamic slices. NO711 alone significantly reduced (41%) the transporter current in NEC, but had no effect in GAERS. SNAP5114 alone reduced by half the GABA transporter current in NEC, whilst it abolished it in GAERS. SIC properties did not differ between GAERS and NEC TC neurons, whilst moderate changes in SOC amplitude and kinetics were observed. These data provide the first direct demonstration of a malfunction of the astrocytic thalamic GAT-1 transporter in absence epilepsy and support an abnormal astrocytic modulation of thalamic ambient GABA levels. Moreover, while the glutamatergic astrocyte-neuron signalling is unaltered in the GAERS thalamus, the changes in some properties of the GABAergic astrocyte-neuron signaling in this epileptic strain may contribute to the generation of absence seizures.

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This article explores how religion as a political force shapes and deflects the struggle for gender equality in contexts marked by different histories of nation building and challenges of ethnic diversity, different state–society relations (from the more authoritarian to the more democratic), and different relations between state power and religion (especially in the domain of marriage, family and personal laws). It shows how ‘private’ issues, related to the family, sexuality and reproduction, have become sites of intense public contestation between conservative religious actors wishing to regulate them based on some transcendent moral principle, and feminist and other human rights advocates basing their claims on pluralist and time- and context-specific solutions. Not only are claims of ‘divine truth’ justifying discriminatory practices against women hard to challenge, but the struggle for gender equality is further complicated by the manner in which it is closely tied up with, and inseparable from, struggles for social and economic justice, ethnic/racial recognition, and national self-determination vis-à-vis imperial/global domination.

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Tanulmányunk azokat a kockázatokat és kihívásokat vizsgálja, amelyekkel az új EU tagállamok szembesülnek az euróhoz vezető úton, valamint elemzi az euró bevezetésével és a bevezetés időzítésével kapcsolatos stratégiákat is. Megvizsgáljuk a reál- és nominálkonvergencia kapcsolatát az euróövezetbe csatlakozás szemszögéből. Véleményünk szerint a gazdaság egy főre jutó jövedelemben mért kezdeti fejlettségi szintje, valamint a reálkonvergencia sebessége kihatnak a követendő stratégiákra és a belépés időzítésére. Minél alacsonyabb ugyanis egy ország egy főre jutó jövedelme, annál nagyobb az árszínvonalbeli lemaradása (amit be kell hoznia), és az új tagok jelenlegi helyzetét figyelembe véve annál nagyobb a veszélye annak, hogy a hitelek növekedése túlzottá, a gazdaság túlfűtötté válik. Úgy gondoljuk, hogy az inflációkövetés lebegő árfolyam mellett megfelelőbb az árszínvonal felzárkózási folyamatának kezelésére, mint valamilyen merev árfolyamrögzítés. Elemezzük a maastrichti kritériumokat az új EU-tagállamok gazdasági jellemzőinek szempontjából, és az inflációs kritérium módosítását javasoljuk, amely jelenlegi formájában elvesztette közgazdasági értelmét. JEL kód: E31, E52, E60, F30. /===/ This paper commissioned by DG ECFIN from the EU Commission as part of the EMU@10 project and published in Hungarian by the permission of the EU Commission. The origi-nal English version is available at http://ec.europa.eu/economy_finance/publications/ publication_summary12103_en.htm. The paper discusses the risks and challenges faced by new members on the road to the euro and the strategies and timing of euro adoption. It investigates the real/nominal convergence nexus from the perspective of euro-area entry, arguing that the initial level of economic development, as measured by per capita income, and the speed of real convergence have a bearing on the strategies to follow and the timing of entry into the euro area, for the lower per capita income is, the larger is the price-level gap to close and the greater the danger of credit booms and overheating. It is argued argue that inflation targeting with floating rates is better suited than hard pegs to managing the price-level catch-up process. A suggestion is made for modifying the Maastricht inflation criterion, which as currently defined has lost its economic logic.

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Kutatásunkban Budapesti Corvinus Egyetem Vállalatgazdaságtan Intézete által az 1995 és 2010 között lebonyolított „Versenyben a világgal” kutatási program kérdőívei alapján a hazai vállalatok versenyképességét befolyásoló tényezőket vizsgáltuk. Eredményeink szerint a krízis hatására az adók versenyképességi jelentősége megnőtt, s – különösen a nagy visszaesést elszenvedőknél – gyakoribbak lettek a piac megőrzését célzó stratégiák. A válság hatását mélyítette, hogy a vállalatok devizakockázat-kezelése nem megfelelő, s a bankok sem tökéletesen szolgálják ki a vállalatok igényeit. Az utóbbi 10-15 esztendőben a késve fizetés egyre gyakoribb lett, s e trendet a válság csak erősítette. _____ Our paper investigates the factors influencing the competitiveness of the Hungarian enterprises based on the research questionnaires of the research program “Companies and competitiveness” of the Business Economics Department at Corvinus University of Budapest carried out between 1995 and 2010. Our results show that due to the crisis the role played by taxes in competitiveness has gained importance, and especially at firms suffering from heavy losses the strategies firstly aiming at keeping markets became more frequent. The effects of the global turndown have been amplified by the weak currency risk management of the Hungarian firms, and by the fact that the service provided by local banks is lagging behind expectations of the companies. During the last 10-15 years the late payment of receivables became more and more frequent in Hungary, a trend that has been even enforced by the depression.

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Persistence of HIV-1 reservoirs within the Central Nervous System (CNS) remains a significant challenge to the efficacy of potent anti-HIV-1 drugs. The primary human Brain Microvascular Endothelial Cells (HBMVEC) constitutes the Blood Brain Barrier (BBB) which interferes with anti-HIV drug delivery into the CNS. The ATP binding cassette (ABC) transporters expressed on HBMVEC can efflux HIV-1 protease inhibitors (HPI), enabling the persistence of HIV-1 in CNS. Constitutive low level expression of several ABC-transporters, such as MDR1 (a.k.a. P-gp) and MRPs are documented in HBMVEC. Although it is recognized that inflammatory cytokines and exposure to xenobiotic drug substrates (e.g HPI) can augment the expression of these transporters, it is not known whether concomitant exposure to virus and anti-retroviral drugs can increase drug-efflux functions in HBMVEC. Our in vitro studies showed that exposure of HBMVEC to HIV-1 significantly up-regulates both MDR1 gene expression and protein levels; however, no significant increases in either MRP-1 or MRP-2 were observed. Furthermore, calcein-AM dye-efflux assays using HBMVEC showed that, compared to virus exposure alone, the MDR1 mediated drug-efflux function was significantly induced following concomitant exposure to both HIV-1 and saquinavir (SQV). This increase in MDR1 mediated drug-efflux was further substantiated via increased intracellular retention of radiolabeled [3H-] SQV. The crucial role of MDR1 in 3H-SQV efflux from HBMVEC was further confirmed by using both a MDR1 specific blocker (PSC-833) and MDR1 specific siRNAs. Therefore, MDR1 specific drug-efflux function increases in HBMVEC following co-exposure to HIV-1 and SQV which can reduce the penetration of HPIs into the infected brain reservoirs of HIV-1. A targeted suppression of MDR1 in the BBB may thus provide a novel strategy to suppress residual viral replication in the CNS, by augmenting the therapeutic efficacy of HAART drugs.

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The amounts, sources and relative ages of inorganic and organic carbon pools were assessed in eight headwater streams draining watersheds dominated by either forest, pasture, cropland or urban development in the lower Chesapeake Bay region (Virginia, USA). Streams were sampled at baseflow conditions six different times over 1 year. The sources and ages of the carbon pools were characterized by isotopic (δ13C and ∆14C) analyses and excitation emission matrix fluorescence with parallel factor analysis (EEM–PARAFAC). The findings from this study showed that human land use may alter aquatic carbon cycling in three primary ways. First, human land use affects the sources and ages of DIC by controlling different rates of weathering and erosion. Relative to dissolved inorganic carbon (DIC) in forested streams which originated primarily from respiration of young, 14C-enriched organic matter (OM; δ13C = −22.2 ± 3 ‰; ∆14C = 69 ± 14 ‰), DIC in urbanized streams was influenced more by sedimentary carbonate weathering (δ13C = −12.4 ± 1 ‰; ∆14C = −270 ± 37 ‰) and one of pasture streams showed a greater influence from young soil carbonates (δ13C = −5.7 ± 2.5 ‰; ∆14C = 69 ‰). Second, human land use alters the proportions of terrestrial versus autochthonous/microbial sources of stream water OM. Fluorescence properties of dissolved OM (DOM) and the C:N of particulate OM (POM) suggested that streams draining human-altered watersheds contained greater relative contributions of DOM and POM from autochthonous/microbial sources than forested streams. Third, human land uses can mobilize geologically aged inorganic carbon and enable its participation in contemporary carbon cycling. Aged DOM (∆14C = −248 to −202 ‰, equivalent14C ages of 1,811–2,284 years BP) and POM (∆14C = −90 to −88 ‰, 14C ages of 669–887 years BP) were observed exclusively in urbanized streams, presumably a result of autotrophic fixation of aged DIC (−297 to −244 ‰, 14C age = 2,251–2,833 years BP) from sedimentary shell dissolution and perhaps also watershed export of fossil fuel carbon. This study demonstrates that human land use may have significant impacts on the amounts, sources, ages and cycling of carbon in headwater streams and their associated watersheds.

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Approaches to quantify the organic carbon accumulation on a global scale generally do not consider the small-scale variability of sedimentary and oceanographic boundary conditions along continental margins. In this study, we present a new approach to regionalize the total organic carbon (TOC) content in surface sediments (<5 cm sediment depth). It is based on a compilation of more than 5500 single measurements from various sources. Global TOC distribution was determined by the application of a combined qualitative and quantitative-geostatistical method. Overall, 33 benthic TOC-based provinces were defined and used to process the global distribution pattern of the TOC content in surface sediments in a 1°x1° grid resolution. Regional dependencies of data points within each single province are expressed by modeled semi-variograms. Measured and estimated TOC values show good correlation, emphasizing the reasonable applicability of the method. The accumulation of organic carbon in marine surface sediments is a key parameter in the control of mineralization processes and the material exchange between the sediment and the ocean water. Our approach will help to improve global budgets of nutrient and carbon cycles.

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Extensive investigations of sedimentary barium were performed in the southern South Atlantic in order to assess the reliability of the barium signal in Antarctic sediments as a proxy for paleoproductivity. Maximum accumulation rates of excess barium were calculated for the Antarctic zone south of the polar front where silica accumulates at high rates. The correspondence between barium and opal supports the applicability of barium as a proxy for productivity. Within the Antarctic zone north of today's average sea ice maximum, interglacial vertical rain rates of excess barium are high, with a maximum occurring during the last deglaciation and early Holocene and during oxygen isotope chronozone 5.5. During these periods, the maximum silica accumulation was supposedly located south of the polar front. Glacial paleoproductivity, instead, was low within the Antarctic zone. North of the polar front, significantly higher barium accumulation occurs during glacial times. The vertical rain rates, however, are as high as in the glacial Antarctic zone. Therefore there was no evidence for an increased productivity in the glacial Southern Ocean.

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Except the non-melanoma skin tumors, colorectal cancer is the second most common in the Southeastern Region of Brazil, the third most common in the Southern and Central Regions. It is also the forth most common in the Northern Region and it is the fifth one in the Northeastern. To assess pathological and clinical variables of colorectal Cancer is crucial to know the possible conclusions for the survival of patients and point out the characteristics in the progress of tumor, such as the profile of tumor invasion and its angiogenesis. This work focuses on analyzing clinically and pathologically some settings in colorectal cancer patients (CRC) in the city of Natal and its countryside through those variables as parameters of prognosis and determine the level of protein expression, for instance: E-cadherin (E-cad), beta- -catenin (β-cat), galectin-3 (gal-3), matrix metalloproteinases (MMP) 2 and 9 and vascular-endothelial growth factor alpha (α VEGF) in the tumor tissues. A retrospective study was done in colorectal cancer cases in the regions of Rio Grande do Norte state from 1995 to 2005, specifically in Natal city/RN/Brazil. The pathological and clinical variables, such as: age, gender, ethnicity, lifestyle, family history, the location of the primary tumor, level of differentiation, TDM staging, modified Dukes’, treatment and survival were analyzed. The pathological and clinical data were collected from medical records through a specific form and were filed on Excel. A total of 534 patients were selected from the Pathology Department file in this institution, however, 176 patients were excluded. 358 patients were included for Epidemiological analysis and its clinical and pathological correlations were selected. 180 patients were also selected for histological and immunohistochemical studies. The tumor progression of these selected proteins mentioned before were analyzed. The Paraffin blocks of these samples were treated by Microarray Tissue technique and its blades subjected to immunohistochemistry to test the intensity of these proteins in tumor tissues. The results of this analysis were correlated with clinicopathologic variables of patients. Statistical analysis using the chi-frame Pearson test and analysis of midlife by Kaplan-Meier curve was also utilized. P values < 0.05 were considered statistically significant. The average age of our sample was 58.8 years and 51.7 % were female. Alcohol consumption has increased by 1.71 time the risk of death by CCR (p = 0.034) and tobacco consumption increased 2.7 times the chance of developing tumors of high TNM stage (p = 0.001). Cancer patients had a family history of 3,833 times the chance of developing the CCR (p = 0.002). The expression of MMP-2 showed a significant association with tumors of high TNM stage (p <0.046) and mortality (p = 0.041). The α VEGF expression had statistically significant correlation with high TNM stage (p <0.009), degree of cell indifferentiation (p <0.025) and mortality (p <0.035). Expressions of E-cadherin and beta-catetina demonstrated tumor linked to high TNM stage (p = 0.0001) and Dukes› modified (p = 0.05), lesions in the rectum (p = 0.03 and p = 0.007, respectively), smoking (p = 0.05) and indifferentiation (p = 0.001). The expression of Gal-3 showed statistical significance with high TNM stage of patients (p = 0.01), smokers (p = 0.01), alcohol drinking (p = 0.03), indifferentiation (p = 0.0001) and mortality (p = 0.0001). Based on the results, therefore, we could realize that lifestyle and family history had correlation in the CCR prognosis, as well as MMP-2 expression, MMP-9, VEGF alpha, E-cadherin, Beta-catenin and Galectin-3 were important prognostic markers in tumor progression in colorectal cancer.

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The signature of Dansgaard-Oeschger events - millennial-scale abrupt climate oscillations during the last glacial period - is well established in ice cores and marine records (Labeyrie, 2000, doi:10.1126/science.290.5498.1905; Blunier and Brook, 2001, doi:10.1126/science.291.5501.109: Bond et al., 2001, doi:10.1126/science.1065680). But the effects of such events in continental settings are not as clear, and their absolute chronology is uncertain beyond the limit of 14C dating and annual layer counting for marine records and ice cores, respectively. Here we present carbon and oxygen isotope records from a stalagmite collected in southwest France which have been precisely dated using 234U/230Th ratios. We find rapid climate oscillations coincident with the established Dansgaard-Oeschger events between 83,000 and 32,000 years ago in both isotope records. The oxygen isotope signature is similar to a record from Soreq cave, Israel (Bar-Mathews et al., 2000, doi:10.1016/S0009-2541(99)00232-6), and deep-sea records (Bond et al., 1993, doi:10.1038/365143a0; Shackleton and Hall, 2001, doi:10.1029/2000PA000513), indicating the large spatial scale of the climate oscillations. The signal in the carbon isotopes gives evidence of drastic and rapid vegetation changes in western Europe, an important site in human cultural evolution. We also find evidence for a long phase of extremely cold climate in southwest France between 61.2 +/-0.6 and 67.4 0.9 kyr ago.

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A set of 114 samples from the sediment surface of the Atlantic, eastern Pacific and western Indian sectors of the Southern Ocean has been analyzed for 230Th and biogenic silica. Maps of opal content, Th-normalized mass flux, and Th-normalized biogenic opal flux into the sediment have been derived. Significant differences in sedimentation patterns between the regions can be detected. The mean bulk vertical fluxes integrated into the sediment in the open Southern Ocean are found in a narrow range from 2.9 g/m**2 yr (Eastern Weddell Gyre) to 15.8 g/m**2 yr (Indian sector), setting upper and lower limits to the vertically received fraction of open ocean sediments. The silica flux to sediments of the Atlantic sector of the Southern Ocean is found to be 4.2 ± 1.4 * 10**11 mol/yr, just one half of the last estimate. This adjustment represents 6% of the output term in the global marine silica budget.