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排序方式: 共有171条查询结果,搜索用时 31 毫秒
31.
Matt Smith Jean Emberlin Alicja Stach Auli Rantio-Lehtimäki Eric Caulton Michel Thibaudon Charlotte Sindt Siegfried Jäger Regula Gehrig Giuseppe Frenguelli Victoria Jato F. Javier Rodríguez Rajo Purificación Alcázar Carmen Galán 《Aerobiologia》2009,25(4):321-332
Relationships between temporal variations in the North Atlantic Oscillation (NAO) and grass pollen counts at 13 sites in Europe, ranging from Córdoba in the south-west and Turku in the north-east, were studied in order to determine spatial differences in the amount of influence exerted by the NAO on the timing and magnitude of grass pollen seasons. There were a number of significant (P < 0.05) relationships between the NAO and start dates of the grass pollen season at the 13 pollen-monitoring sites. The strongest associations were generally recorded near to the Atlantic coast. Several significant correlations also existed between winter averages of the NAO and grass pollen season severity. Traditional methods for predicting the start or magnitude of grass pollen seasons have centred on the use of local meteorological observations, but this study has shown the importance of considering large-scale patterns of climate variability like the NAO. 相似文献
32.
Robertson BC Frauenfelder N Eason DK Elliott G Moorhouse R 《Molecular ecology resources》2009,9(2):664-666
Thirty polymorphic microsatellite loci were developed from the critically endangered kakapo (Strigops habroptilus), using an enriched genomic library. Characterization of loci using 90 kakapo revealed an average of 3.3 alleles per locus (range: 2–5) and an average expected heterozygosity of 0.47 (range: 0.17–0.70). The probability of identity (7.2 × 10?15) and probability of exclusion (0.999999) demonstrate that these loci are a highly informative marker set that can aid the genetic management of the kakapo. 相似文献
33.
Changes in temperature sensitivity of spring phenology with recent climate warming in Switzerland are related to shifts of the preseason
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Sabine Güsewell Reinhard Furrer Regula Gehrig Barbara Pietragalla 《Global Change Biology》2017,23(12):5189-5202
The spring phenology of plants in temperate regions strongly responds to spring temperatures. Climate warming has caused substantial phenological advances in the past, but trends to be expected in the future are uncertain. A simple indicator is temperature sensitivity, the phenological advance statistically associated with a 1°C warmer mean temperature during the “preseason”, defined as the most temperature‐sensitive period preceding the phenological event. Recent analyses of phenological records have shown a decline in temperature sensitivity of leaf unfolding, but underlying mechanisms were not clear. Here, we propose that climate warming can reduce temperature sensitivity simply by reducing the length of the preseason due to faster bud development during this time period, unless the entire preseason shifts forward so that its temperature does not change. We derive these predictions theoretically from the widely used “thermal time model” for bud development and test them using data for 19 phenological events recorded in 1970–2012 at 108 stations spanning a 1600 m altitudinal range in Switzerland. We consider how temperature sensitivity, preseason start, preseason length and preseason temperature change (i) with altitude, (ii) between the periods 1970–1987 and 1995–2012, which differed mainly in spring temperatures, and (iii) between two non‐consecutive sets of 18 years that differed mainly in winter temperatures. On average, temperature sensitivity increased with altitude (colder climate) and was reduced in years with warmer springs, but not in years with warmer winters. These trends also varied among species. Decreasing temperature sensitivity in warmer springs was associated with a limited forward shift of preseason start, higher temperatures during the preseason and reduced preseason length, but not with reduced winter chilling. Our results imply that declining temperature sensitivity can result directly from spring warming and does not necessarily indicate altered physiological responses or stronger constraints such as reduced winter chilling. 相似文献
34.
The start date of flowering of allergenic species is of great interest in the context of allergy. Such forecasts can help to plan the therapy and design the medical treatment. For this purpose, temperature sum models are usually employed. Designing temperature sum models requires the selection of different parameters such as the base temperature and the start date for the temperature sum. However, the optimal parameterization is often unknown and varies depending on location and species. The purpose of this study was to systematically test parameterizations of temperature sum models based on 12 Swiss pollen stations. The examined taxa include Corylus, Alnus, Fraxinus, Betula, and Poaceae. We tested the simple thermal model type (forcing-only model hereafter) which relies solely on forcing temperatures and the sequential model type that includes also chilling temperatures. The mean absolute error was used to assess the performance of the models. Our study shows that the sequential model could not achieve a discernible reduction of the (statistical) error compared to the forcing-only model for all taxa. The mean absolute error lies roughly between 2 and 4 days with the lowest values for Betula. The optimized parameterizations in combination with temperature forecast and the climatological mean were used during the 2012 pollen season to provide daily updated forecasts of the start of flowering for all five taxa. Improvements of the models could possibly be achieved by testing additional temperature parameters as well as other meteorological factors such as precipitation or irradiation. Identification of a process-oriented model with high statistical performance for all stations would facilitate the implementation in numerical pollen dispersion models. 相似文献
35.
Fabian D. Liechti Nicolas Stüdle Regula Theurillat Denis Grandgirard Wolfgang Thormann Stephen L. Leib 《PloS one》2014,9(11)
Pneumococcal meningitis is associated with high morbidity and mortality rates. Brain damage caused by this disease is characterized by apoptosis in the hippocampal dentate gyrus, a morphological correlate of learning deficits in experimental paradigms. The mood stabilizer lithium has previously been found to attenuate brain damage in ischemic and inflammatory diseases of the brain. An infant rat model of pneumococcal meningitis was used to investigate the neuroprotective and neuroregenerative potential of lithium. To assess an effect on the acute disease, LiCl was administered starting five days prior to intracisternal infection with live Streptococcus pneumoniae. Clinical parameters were recorded, cerebrospinal fluid (CSF) was sampled, and the animals were sacrificed 42 hours after infection to harvest the brain and serum. Cryosections of the brains were stained for Nissl substance to quantify brain injury. Hippocampal gene expression of Bcl-2, Bax, p53, and BDNF was analyzed. Lithium concentrations were measured in serum and CSF. The effect of chronic lithium treatment on spatial memory function and cell survival in the dentate gyrus was evaluated in a Morris water maze and by quantification of BrdU incorporation after LiCl treatment during 3 weeks following infection. In the hippocampus, LiCl significantly reduced apoptosis and gene expression of Bax and p53 while it increased expression of Bcl-2. IL-10, MCP-1, and TNF were significantly increased in animals treated with LiCl compared to NaCl. Chronic LiCl treatment improved spatial memory in infected animals. The mood stabilizer lithium may thus be a therapeutic alternative to attenuate neurofunctional deficits as a result of pneumococcal meningitis. 相似文献
36.
Roger R Beerli Monika Bauer Andrea Fritzer Lindsey B Rosen Regula B Buser Markus Hanner Melanie Maudrich Mario Nebenfuehr Jorge Alejandro Sepulveda Toepfer Susanne Mangold Anton Bauer Steven M Holland Sarah K Browne Andreas Meinke 《MABS-AUSTIN》2014,6(6):1608-1620
Anti-cytokine autoantibodies have been widely reported to be present in human plasma, both in healthy subjects and in patients with underlying autoimmune conditions, such as autoimmune polyendocrinopathy candidiasis ectodermal dystrophy (APECED) or thymic epithelial neoplasms. While often asymptomatic, they can cause or facilitate a wide range of diseases including opportunistic infections. The potential therapeutic value of specific neutralizing anti-cytokine autoantibodies has not been thoroughly investigated. Here we used mammalian cell display to isolate IL17A-specific antibodies from a thymoma patient with proven high-titer autoantibodies against the same. We identified 3 distinct clonotypes that efficiently neutralized IL17A in a cell-based in vitro assay. Their potencies were comparable to those of known neutralizing antibodies, including 2, AIN457 (secukinumab) and ixekizumab that are currently in clinical development for the treatment of various inflammatory disorders. These data clearly demonstrate that the human autoantibody repertoire can be mined for antibodies with high therapeutic potential for clinical development. 相似文献
37.
Luis Fernando Garcia-Alles Karin Flükiger Johannes Hewel Regula Gutknecht Christian Siebold Stefan Schürch Bernhard Erni 《The Journal of biological chemistry》2002,277(9):6934-6942
Four phosphoenolpyruvate (PEP) derivatives, carrying reactive or activable chemical functions in each of the three chemical regions of PEP, were assayed as alternative substrates of enzyme I (EI) of the Escherichia coli PEP:glucose phosphotransferase system. The Z- and E-isomers of 3-chlorophosphoenolpyruvate (3-Cl-PEP) were substrates, presenting K(m) values of 0.08 and 0.12 mm, respectively, very similar to the K(m) of 0.14 mm measured for PEP, and k(cat) of 40 and 4 min(-1), compared with 2,200 min(-1), for PEP. The low catalytic efficiency of these substrates permits the study of activity at in vivo EI concentrations. Z-Cl-PEP was a competitive inhibitor of PEP with a K(I) of 0.4 mm. E-Cl-PEP was not an inhibitor. Compounds 3 and 4, obtained by modification of the carboxylic and phosphate groups of PEP, were neither substrates nor inhibitors of EI, highlighting the importance of these functionalities for recognition by EI. Z-Cl-PEP is a suicide inhibitor. About 10-50 turnovers sufficed to inactivate EI completely. Such a property can be exploited to reveal and quantitate phosphoryl transfer from EI to other proteins at in vivo concentrations. Inactivation was saturatable in Z-Cl-PEP, with an apparent K(m)(inact) of 0.2-0.4 mm. The rate of inactivation increased with the concentration of EI, indicating a preferential or exclusive reaction with the dimeric form of EI. E-Cl-PEP inactivates EI much more slowly, and unlike PEP, it did not protect against inactivation by Z-Cl-PEP. This and the ineffectiveness of E-Cl-PEP as a competitive inhibitor have been related to the presence of two EI active species. Cys-502 of EI was identified by mass spectrometry as the reacting residue. The C502A EI mutant showed less than 0.06% wild-type activity. Sequence alignments and comparisons of x-ray structures of different PEP-utilizing enzymes indicate that Cys-502 might serve as a proton donor during catalysis. 相似文献
38.
39.
Niels Jungbluth Regula Keller Alex König 《The International Journal of Life Cycle Assessment》2016,21(5):646-653
Purpose
Private food consumption accounts for 30 % of total environmental impacts caused by the final consumption of Swiss households. The private expenses for gastronomy and hotels account for another 6 %. Therefore, it is necessary to investigate and better understand the environmental impacts of food consumption and the possibilities for a reduction of these impacts. This was the starting point for the collaboration between the canteen operator SV Group, the life cycle assessment (LCA) consultancy ESU-services, the energy supplier ewz and the World Wide Fund for Nature (WWF) in Switzerland focusing on food consumption in canteens.Methods
In a first step, an LCA study was used to analyse the environmental impacts of about 20 million meals served in 240 canteens in 2011. LCA data for 160 food items were linked to the food amounts of about 10,000 articles purchased in this year. This was supplemented by data on canteen operation and resulted in a full organisational LCA.Results and discussion
The impacts of food purchases are about four times higher than the direct impacts due to the operation of the canteens. The most important product groups are meat and dairy products. Improvement potentials have been identified within 14 different themes by the project group. They include measures in the canteen operation (e.g. reduction of food waste or energy-efficient appliances); measures in the supply chain, e.g. a reduction of vegetables grown in heated greenhouses; or the abandonment of air-transported products. But also dietary choices such as a reduction of the average amount of meat per meal are considered as an option. The results and recommendations of the detailed LCA as well as information by other partners have been used by the SV Group to develop the programme ONE TWO WE. It assists the customers (companies who commission the operation of canteens in their premises) to reach improved levels of environmental performance. The programme aims for a 20 % cut on GHG emissions after full implementation in the participating canteens.Conclusions
The programme started successfully with many customers positively convinced by the proposed changes in the provision of canteen meals. An initial reduction of greenhouse gas emissions compared to the baseline was achieved. This LCA study is a good example for the value of calculating a full organisational environmental footprint for a company in the gastronomy sector and for using the results of such a study to bring down the overall environmental impacts.40.
Regula K Kirshenbaum LA 《Apoptosis : an international journal on programmed cell death》1999,4(4):229-234
Apoptosis or programmed cell death is an important physiologic event crucial for the selective removal of damaged or unwanted cells from body tissues. In the cardiovascular system, apoptosis has been observed in the vasculature and myocardium. Untimely or inappropriate myocardial cell loss through an apoptotic process may contribute to ventricular remodeling and the ultimate demise of ventricular function following injury. Therapeutic interventions designed to modulate or prevent myocardial apoptotic cell loss may therefore prove beneficial in maintaining cardiac function. Incite into the molecular mechanisms that govern apoptosis in mammalian cells has led to the identification of several key factors that promote or prevent the apoptotic process. In this report, we discuss putative regulators of cardiac cell apoptosis with specific reference to the tumor suppressor proteins, p53 and Rb. The interplay between these factors, as well as the anti-apoptotic molecules related to the Bcl-2 the family are discussed in the context of the heart under normal and disease conditions. 相似文献