944 resultados para Drop Tower Beijing


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The frequency of the Beijing genotype of Mycobacterium tuberculosis as a cause of tuberculosis (TB) in South America was determined by analyzing genotypes of strains isolated from patients that had been diagnosed with the disease between 1997 and 2003 in seven countries of the subcontinent. In total, 19 of the 1,202 (1.6%) TB cases carried Beijing isolates, including 11 of the 185 patients from Peru (5.9%), five of the 512 patients from Argentina (1.0%), two of the 252 Brazilian cases (0.8%), one of the 166 patients from Paraguay (0.6%) and none of the samples obtained from Chile (35), Colombia (36) and Ecuador (16). Except for two patients that were East Asian immigrants, all cases with Beijing strains were native South Americans. No association was found between carrying a strain with the Beijing genotype and having drug or multi-drug resistant disease. Our data show that presently transmission of M. tuberculosis strains of the Beijing genotype is not frequent in Latin America. In addition, the lack of association of drug resistant TB and infection with M. tuberculosis of the Beijing genotype observed presently demands efforts to define better the contribution of the virulence and lack of response to treatment to the growing spread of Beijing strains observed in other parts of the world.

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BACKGROUND. The Beijing lineage of Mycobacterium tuberculosis is causing concern due to its global distribution and its involvement in severe outbreaks. Studies focused on this lineage are mainly restricted to geographical settings where its prevalence is high, whereas those in other areas are scarce. In this study, we analyze Beijing isolates in the Mediterranean area, where this lineage is not prevalent and is mainly associated with immigrant cases. RESULTS. Only 1% (N = 26) of the isolates from two population-based studies in Spain corresponded to Beijing strains, most of which were pan-susceptible and from Peruvian and Ecuadorian patients. Restriction fragment length polymorphism typing with the insertion sequence IS6110 identified three small clusters (2-3 cases). Mycobacterial interspersed repetitive unit-variable number tandem repeat typing (MIRU-15) offered low discriminatory power, requiring the introduction of five additional loci. A selection of the Beijing isolates identified in the Spanish sample, together with a sample of Beijing strains from Italy, to broaden the analysis context in the Mediterranean area, were assayed in an infection model with THP-1 cells. A wide range of intracellular growth rates was observed with only two isolates showing an increased intracellular replication, in both cases associated with contained production of TNF-alpha. No correlation was observed between virulence and the Beijing phylogenetic group, clustered/orphan status, or resistance. The Beijing strain responsible for extensive spread on Gran Canaria Island was also identified in Madrid, but did not lead to secondary cases and did not show high infectivity in the infection model. CONCLUSIONS. The Beijing lineage in our area is a non-homogeneous family, with only certain highly virulent representatives. The specific characterization of Beijing isolates in different settings could help us to accurately identify the virulent representatives before making general assumptions about this lineage.

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This study examines the importance of change in characteristics and circumstances ofhouseholds and household members for contact and cooperation patterns. The literaturesuggests that there might be an underrepresentation of change in panel studies, becauserespondents facing more changes would be more likely to drop out. We approach this problemby analysing whether previous changes are predictive of later attrition or temporary drop-out,using eleven waves of the Swiss Household Panel (1999-2009). Our analyses supportprevious findings to some extent. Changes in household composition, employment status andsocial involvement as well as moving are associated mainly with attrition and less withtemporary drop-out. These changes affect obtaining cooperation rather than obtaining contact,and tend to increase attrition.

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Combining data from police statistics and crime victim surveys, this article analyses the evolution of crime in Western Europe from 1988 to 2007. The results show that there is no general drop in crime. Property offences and homicide have been decreasing since the mid 1990s, while violent and drug offences have increased during the period under study. These trends highlight the limits of the explanations to the crime drop in the United States, which are based on the premise of a correlation in the evolution of all offences. The drop in property offences seems related to changes in the socioeconomic situation in Europe as well as to increases in security measures in households, and the reinforcement of private security. The increase in violent offences can be explained by the combination of several factors, including changes in youth's free time provoked by the development of the Internet, changing demographics, and the rise of episodic heavy alcohol consumption and street gangs.

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BACKGROUND & AIMS: In the last decade, pegylated interferon-α (PegIFN-α) plus ribavirin (RBV) was the standard treatment of chronic hepatitis C for genotype 1, and it remains the standard for genotypes 2 and 3. Recent studies reported associations between RBV-induced anemia and genetic polymorphisms of concentrative nucleoside transporters such as CNT3 (encoded by SLC28A3) and inosine triphosphatase (encoded by ITPA). We aimed at studying genetic determinants of RBV kinetics, efficacy and treatment-associated anemia. METHODS: We included 216 patients from two Swiss study cohorts (61% HCV genotype 1, 39% genotypes 2 or 3). Patients were analyzed for SLC28A2 single nucleotide polymorphism (SNP) rs11854484, SLC28A3 rs56350726, and SLC28A3 rs10868138 as well as ITPA SNPs rs1127354 and rs7270101, and followed for treatment-associated hemoglobin changes and sustained virological response (SVR). In 67 patients, RBV serum levels were additionally measured during treatment. RESULTS: Patients with SLC28A2 rs11854484 genotype TT had higher dosage- and body weight-adjusted RBV levels than those with genotypes TC or CC (p=0.02 and p=0.06 at weeks 4 and 8, respectively). ITPA SNP rs1127354 was associated with hemoglobin drop ≥3 g/dl during treatment, in genotype (relative risk (RR)=2.1, 95% CI 1.3-3.5) as well as allelic analyses (RR=2.0, 95%CI 1.2-3.4). SLC28A3 rs56350726 was associated with SVR in genotype (RR=2.2; 95% CI 1.1-4.3) as well as allelic analyses (RR=2.0, 95% CI 1.1-3.4). CONCLUSIONS: The newly identified association between RBV serum levels and SLC28A2 rs11854484 genotype, as well as the replicated association of ITPA and SLC28A3 genetic polymorphisms with RBV-induced anemia and treatment response, may support individualized treatment of chronic hepatitis C and warrant further investigation in larger studies.

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Combining data from police statistics and crime victim surveys, this article analyses the evolution of crime in Western Europe from 1988 to 2007. The results show that there is no general drop in crime. Property offences and homicide have been decreasing since the mid 1990s, while violent and drug offences have increased during the period under study. These trends highlight the limits of the explanations to the crime drop in the United States, which are based on the premise of a correlation in the evolution of all offences. The drop in property offences seems related to changes in the socioeconomic situation in Europe as well as to increases in security measures in households, and the reinforcement of private security. The increase in violent offences can be explained by the combination of several factors, including changes in youth's free time provoked by the development of the Internet, changing demographics, and the rise of episodic heavy alcohol consumption and street gangs.

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A vehicle may leave its travel lane for a number of reasons, such as driver error, poor surface conditions, or avoidance of a collision with another vehicle in the travel lane. When a vehicle leaves the travel lane, pavement edge drop-off poses a potential safety hazard because significant vertical differences between surfaces can affect vehicle stability and reduce a driver’s ability to handle the vehicle. Numerous controlled studies have tested driver response to encountering drop-offs under various conditions, including different speeds, vehicle types, drop-off height and shape, and tire scrubbing versus non-scrubbing conditions. The studies evaluated the drivers’ ability to return to and recover within their own travel lane after leaving the roadway and encountering a drop-off. Many of these studies, however, have used professional drivers as test subjects, so results may not always apply to the population of average drivers. Furthermore, test subjects are always briefed on what generally is to be expected and how to respond; thus, the sense of surprise that a truly naïve driver may experience upon realizing that one or two of his or her tires have just dropped off the edge of the pavement, is very likely diminished. Additionally, the studies were carried out under controlled conditions. The actual impact of pavement edge drop-off on drivers’ ability to recover safely once they leave the roadway, however, is not well understood under actual driving conditions. Additionally, little information is available that quantifies the number or severity of crashes that occur where pavement edge drop-off may have been a contributing factor. Without sufficient information about the frequency of edge drop-off-related crashes, agencies are not fully able to measure the economic benefits of investment decisions, evaluate the effectiveness of different treatments to mitigate edge drop-off, or focus maintenance resources. To address these issues, this report details research to quantify the contribution of pavement edge drop-off to crash frequency and severity. Additionally, the study evaluated federal and state guidance in sampling and addressing pavement edge drop-off and quantified the extent of pavement edge drop-off in two states. This study focused on rural two-lane paved roadways with unpaved shoulders, since they are often high speed facilities (55+ mph), have varying levels of maintenance, and are likely to be characterized by adverse roadway conditions such as narrow lanes or no shoulders.

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The purpose of this study was to examine the physiological and biomechanical changes occurring in a subject after running 8,500 km in 161 days (i.e. 52.8 km daily). Three weeks before, 3 weeks after (POST) and 5 months after (POST+5) running from Paris to Beijing, energy cost of running (Cr), knee flexor and extensor isokinetic strength and biomechanical parameters (using a treadmill dynamometer) at different velocities were assessed in an experienced ultra-runner. At POST, there was a tendency toward a 'smoother' running pattern, as shown by (a) a higher stride frequency and duty factor, and a reduced aerial time without a change in contact time, (b) a lower maximal vertical force and loading rate at impact and (c) a decrease in both potential and kinetic energy changes at each step. This was associated with a detrimental effect on Cr (+6.2%) and a loss of strength at all angular velocities for both knee flexors and extensors. At POST+5, the subject returned to his original running patterns at low but not at high speeds and maximal strength remained reduced at low angular velocities (i.e. at high levels of force). It is suggested that the running pattern changes observed in the present study were a strategy adopted by the subject to reduce the deleterious effects of long distance running. However, the running pattern changes could partly be linked to the decrease in maximal strength.

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We show that small amounts of 3He atoms, added to a 4He drop deposited on a flat cesium surface at zero temperature, populate bound states localized at the contact line. These edge states show up for drops large enough to develop well defined surface and bulk regions together with a contact line, and they are structurally different from the well-known Andreev states that appear at the free surface and at the liquid-solid interface of films. We illustrate the one-body density of 3He in a drop with 1000 4He atoms, and show that for a sufficiently large number of impurities the density profiles spread beyond the edge, coating both the curved drop surface and its flat base and eventually isolating it from the substrate.

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Using a panel data for non-OECD countries covering the period 1970-2012, this chapter analyzes the impact of the duration of primary education on school enrollment, drop-out and completion rates. The empirical results show that for children in elementary school one ad- ditional grade of primary education have a negative impact on the enrollment rate, while the e ect on drop-outs is positive. Analogously, it is obtained that an additional grade in primary education reduces the enrollment rate in secondary education. These results are in line with the fertility model approach, that is, in developing and underdeveloped countries parents do not have incentive to send children to school given the high perceived economic value of children.