78 resultados para Inner Mongolian steppe

em BORIS: Bern Open Repository and Information System - Berna - Suiça


Relevância:

100.00% 100.00%

Publicador:

Resumo:

Semi-arid ecosystems play an important role in regulating global climate with the fate of these ecosystems in the Anthropocene depending upon interactions among temperature, precipitation, and CO2. However, in cool-arid environments, precipitation is not the only limitation to forest productivity. Interactions between changes in precipitation and air temperature may enhance soil moisture stress while simultaneously extending growing season length, with unclear consequences for net carbon uptake. This study evaluates recent trends in productivity and phenology of Inner Asian forests (in Mongolia and Northern China) using satellite remote sensing, dendrochronology, and dynamic global vegetation model (DGVM) simulations to quantify the sensitivity of forest dynamics to decadal climate variability and trends. Trends in photosynthetically active radiation fraction (FPAR) between 1982 and 2010 show a greening of about 7% of the region in spring (March, April, May), and 3% of the area ‘browning’ during summertime (June, July, August). These satellite observations of FPAR are corroborated by trends in NPP simulated by the LPJ DGVM. Spring greening trends in FPAR are mainly explained by long-term trends in precipitation whereas summer browning trends are correlated with decreasing precipitation. Tree ring data from 25 sites confirm annual growth increments are mainly limited by summer precipitation (June, July, August) in Mongolia, and spring precipitation in northern China (March, April, May), with relatively weak prior-year lag effects. An ensemble of climate projections from the IPCC CMIP3 models indicates that warming temperatures (spring, summer) are expected to be associated with higher summer precipitation, which combined with CO2 causes large increases in NPP and possibly even greater forest cover in the Mongolian steppe. In the absence of a strong direct CO2 fertilization effect on plant growth (e.g., due to nutrient limitation), water stress or decreased carbon gain from higher autotrophic respiration results in decreased productivity and loss of forest cover. The fate of these semi-arid ecosystems thus appears to hinge upon the magnitude and subtleties of CO2 fertilization effects, for which experimental observations in arid systems are needed to test and refine vegetation models.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Patients with autoimmune inner ear disease develop rapidly progressive sensorineural hearing loss over a period of several weeks or months, often accompanied by vestibular loss. This disease can occur as a distinct clinical entity or in association with an underlying autoimmune disorder. Treatment comprises immunosuppression by corticosteroids, cytostatic drugs or tumor necrosis factor- antagonists. We report histopathological and immunohistochemical findings of the inner ear of a patient with a granulomatous inner ear disease suffering from Crohn's disease that was nonresponsive to treatment and who underwent surgery for bilateral cochlear implants.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Background Switzerland is confronted with the problem of interpersonal violence. Violence is in the increase and the potential for aggression seems to be rising. Observations by hospitals discern an appalling increase of the severity of the injuries. The aim of this study is to collect accurate information about the social environment, the motivation and possible reasons for violence. We also intend to investigate whether sociocultural, or ethnic differences among male victims exist. Materials and methods For the first time in Switzerland, this survey employed a validated questionnaire from the division of violence prevention, Atlanta, Georgia. The first part of the questionnaire addressed social and demographic factors which could influence the risk of violence: age, gender, duration of stay in Switzerland, nationality and educational level. Beside these social structural factors, the questionnaire included questions on experience of violent offences in the past, information about the most recent violent offence and intra and interpersonal facts. The questionnaire itself consists of 27 questions, translated into German and French. In a pilot study, the questionnaire was checked with adolescents for feasibility and comprehensibility. Results 69 male VIVs were interviewed at two hospitals in the Canton of Bern. Most of the adolescents emphasised that weapons were not used during their confrontations. It is astonishing that all of the young men considered themselves to be victims. Most of the brawls were incited after an exchange of verbal abuse and provocations with unfamiliar individuals. The rivals could neither be classified with the help of ethnic categories nor identifiable groups of the youth scenes. The incidents took place in scenes, where violence was more likely to happen. Interestingly and contrary to a general perception the offenders are well integrated into sport and leisure clubs. A further surprising result of our research is that the attitude towards religion differs between young men with experience of violence and non-violent men. Discussion Youth violence is a health issue, which concerns us globally. The human and economic toll of violence on victims and offenders, their families, and on society in general is high. The economic costs associated with violence-related illness and disability is estimated to be millions of Swiss francs each year. Physicians and psychologists are compelled to identify the factors, which cause young people to be violent, to find out which interventions prove to be successful, and to design effective prevention programs. The identification of effective programs depends on the availability of reliable and valid measures to assess changes in violence-related attitudes. In our efforts to create healthier communities, we need to investigate; document and do research on the causes and circumstances of youth violence.