In this contribution air temperature differences among Local Climate Zone (LCZ) categories are analysed with special consideration of varying synoptic conditions. Analyses are based upon an LCZ ...mapping for the urban area of Augsburg (Bavaria, Southern Germany) and hourly air temperature data from a comprehensive logger network. Quality checked air temperature measurements have been stratified according to season, hour of the day and weather situation. For resulting subsamples thermal differences among LCZs have been determined and appropriate statistical tests have been applied. Results confirm that built up LCZs feature higher temperatures than natural LCZs and that most distinct differences among LCZs appear under undisturbed synoptic conditions. With increasing cloudiness and in particular with increasing wind speed differences among LCZs diminish. But, even for strongly disturbed synoptic conditions statistical significance of the influence of LCZs on thermal characteristics could be assured. Thus, our findings provide clear evidence that detectable thermal differences among LCZs are not restricted to „ideal “synoptic conditions but occur as well under disturbed conditions. However, to assure not only the statistical but also the climatological and in particular the bioclimatological and human health related relevance of the documented differences among LCZs further studies incorporating appropriate metrics are intended.
Spatial and temporal variability of meteorological variables across urban areas due to differences in land surface characteristics is a common phenomenon. Most pronounced is the effect of land cover ...on air temperature. In this study, parametric and non-parametric statistical approaches (stepwise multiple linear regression, random forests) were applied in order to model sub-daily and daily spatial patterns of the urban heat island intensity in the major city of Augsburg, Southern Germany, and its rural surroundings. A large number of model setups utilizing variables from different land surface data sets as predictors and taking into account different seasonal, daily and meteorological situations was examined. The results were compared concerning different measures of model performance (mean squared skill score, mean squared error, explained variance). For individual setups and situations considerable skill with a mean squared skill score of up to 0.85 was reached. The best performing models were obtained from multiple linear regression for situations with low wind speeds and cloud cover in the morning and evening. Selected models were utilized to derive continuous spatial distributions of the air temperature deviations from a rural reference station. The resulting maps can be useful for various applications, e.g. in the context of urban planning.
•UHI intensities were modelled using multiple linear regression and random forests•A large number of varying model setups was evaluated•Continuous spatial patterns of UHI intensities were derived from selected models•Best models were obtained for morning and evening for calm and clear situations•Spatial differences in UHI intensity could be clearly related to land cover characteristics
Meteorological factors seem to influence stroke incidence, however, the complex association between weather and stroke remains unclear. Possible explanations from the literature do not categorize ...into subdivisions of ischemic strokes, only have small patient numbers, or refer to a selection of isolated weather elements without investigating weather changes and more.
In this exploratory trial, almost 18,000 stroke cases from a single stroke center in Southern Germany were analyzed from 2006 to 2015 and classified into the main subgroups of strokes and subdivisions of ischemic stroke etiologies applying the Trial of Org 10172 in Acute Stroke Treatment classification. For each stroke event, the air mass classification was determined from a subset of 7 air mass categories. Relative excess morbidities were derived for the 7 different air mass categories, taking into account the day of the event and up to 2 and 5 days preceding the stroke event.
Statistically significant findings (α ≤0.1) reveal that dry tropical air masses were associated with a lower/higher risk for hemorrhagic (HEM)/macroangiopathic strokes (MAS), respectively. Dry polar air masses were associated with a higher risk for intracerebral bleedings and lower risk for ischemic stroke subtypes. Moist air masses were associated with a reduced incidence of MAS. A strong temperature increase 5 days prior to the event was associated with a lower risk of HEM strokes. Temperature increases were associated with lower risks for MAS and cardio-embolic strokes. Significant temperature decreases were associated with a higher risk of MAS.
Temperature effects were dependent on both air masses and temperature changes within 5 days prior to the event and were associated with statistically relevant changes in stroke incidence. Decisive factors such as etiology, age, sex, and risk factors were also taken into account.
Higher incidences of asthma during thunderstorms can pose a serious health risk. In this study, we estimate the thunderstorm asthma risk using statistical methods, with special focus on Bavaria, ...Southern Germany. In this approach, a dataset of asthma-related emergency cases for the study region is combined with meteorological variables and aeroallergen data to identify statistical relationships between the occurrence of asthma (predictand) and different environmental parameters (set of predictors). On the one hand, the results provide evidence for a weak but significant relationship between atmospheric stability indices and asthma emergencies in the region, but also show that currently thunderstorm asthma is not a major concern in Bavaria due to overall low incidences. As thunderstorm asthma can have severe consequences for allergic patients, the presented approach can be important for the development of emergency strategies in regions affected by thunderstorm asthma and under present and future climate change conditions.
Phosducin has recently been identified as a cytosolic protein that interacts with the βγ-subunits of G proteins and thereby may regulate transmembrane signaling. It is expressed predominantly in the ...retina but also in many other tissues, which raises the question of its potential specificity for retinal versus nonretinal βγ-subunits. We have therefore expressed and purified different combinations of β- and γ-subunits from Sf9 cells and have also purified transducin-βγ from bovine retina and a mixture of βγ complexes from bovine brain. Their interactions with phosducin were determined in a variety of assays for βγ function: support of ADP-ribosylation of αo by pertussis toxin, enhancement of the GTPase activity of αo, and enhancement of rhodopsin phosphorylation by the β-adrenergic receptor kinase 1 (βARK1). There were only moderate differences in the effects of the various βγ complexes alone on αo, but there were marked differences in their ability to support βARK1 catalyzed rhodopsin phosphorylation. Phosducin inhibited all βγ-mediated effects and showed little specificity toward specific defined βγ complexes with the exception of transducin-βγ (β1γ1), which was inhibited more efficiently than the other βγ combinations. In a direct binding assay, there was no apparent selectivity of phosducin for any βγ combination tested. Thus, in contrast to βARK1, phosducin does not appear to discriminate strongly between different G protein β- and γ-subunits.
Phosphorylation of G protein-coupled receptors by β-adrenergic receptor kinases (βARK) requires the presence of G protein βγ subunits. We have investigated the ability of the two βARK isoforms to ...distinguish between defined recombinant βγ subunits. βARK2 had an about 25% lower specific activity than βARK1 towards rhodopsin and the β
2-adrenergic receptor but the two kinases shared the selectivity for βγ subunits: βγ complexes consisting of β
1 or β
2 in combination with γ
2, γ
5, and γ
7 were more efficacious than those with γ
3 or β
1γ
1. Thus, while βARKs differentiate between defined βγ subunits, βγ complexes do not discriminate between βARK isoforms.
Arrestins are cytosolic proteins involved in the desensitization of G-protein-coupled receptors. We report the cloning of trout red blood cell arrestin which shows 76, 82 and 52% identity with bovine ...beta-arrestin1, beta-arrestin2 and retinal arrestin respectively. Antibodies were generated against the C-terminus of trout red blood cell arrestin. These antibodies detected arrestin in erythrocyte cytosol and were able to precipitate the native protein. The Na+/H+ antiporter of trout red blood cell is activated by beta-adrenergic stimulation and is then desensitized whereas the transmembrane signalling pathway is not. To investigate the subcellular distribution of arrestin on beta-adrenergic activation and desensitization of the antiporter, precipitation experiments were carried out on trout erythrocytes. A desensitization-dependent shift in cytosolic arrestin to the membranes could not be detected using the immunoprecipitation technique but we cannot exclude the possibility that a small number of cytosolic arrestins might be involved in the regulation of membrane proteins in trout erythrocyte. Recombinant trout arrestin was produced in a protease-deficient Escherichia coli strain and its functionality was tested in a reconstituted rhodopsin assay. The recombinant protein provides a suitable tool for investigating the target for arrestin in trout red blood cell, which still remains to be identified.
Phosducin has recently been identified as a cytosolic protein that interacts with the β -subunits of G proteins and thereby may regulate transmembrane signaling. It is expressed predominantly in the ...retina but
also in many other tissues, which raises the question of its potential specificity for retinal versus nonretinal β -subunits. We have therefore expressed and purified different combinations of β- and -subunits from Sf9 cells and have also purified transducin-β from bovine retina and a mixture of β complexes from bovine brain. Their interactions with phosducin were determined in a variety of assays for β function: support of ADP-ribosylation of α by pertussis toxin, enhancement of the GTPase activity of α , and enhancement of rhodopsin phosphorylation by the β-adrenergic receptor kinase 1 (βARK1). There were only moderate differences
in the effects of the various β complexes alone on α , but there were marked differences in their ability to support βARK1 catalyzed rhodopsin phosphorylation. Phosducin inhibited
all β -mediated effects and showed little specificity toward specific defined β complexes with the exception of transducin-β (β ), which was inhibited more efficiently than the other β combinations. In a direct binding assay, there was no apparent selectivity of phosducin for any β combination tested. Thus, in contrast to βARK1, phosducin does not appear to discriminate strongly between different G protein
β- and -subunits.
Climate change is expected to exacerbate the frequency of drought-induced tree mortality world-wide. To better predict the associated change of species composition and forest dynamics on various ...scales and develop adequate adaptation strategies, more information on the mechanisms driving the often observed patchiness of tree die-back is needed. Although forest-edge effects may play an important role within the given context, only few corresponding studies exist. Here, we investigate the regional die-back of Scots pine in Franconia, Germany, after a hot and dry summer in 2015, thereby emphasizing possible differences in mortality between forest edge and interior. By means of dendroecological investigations and close-range remote sensing, we assess long-term growth performance and current tree vitality along five different forest-edge distance gradients. Our results clearly indicate a differing growth performance between edge and interior trees, associated with a higher vulnerability to drought, increased mortality rates, and lower tree vitality at the forest edge. Prior long-lasting growth decline of dead trees compared to live trees suggests depletion of carbon reserves in course of a long-term drought persisting since the 1990s to be the cause of regional Scots pine die-back. These findings highlight the forest edge as a potential focal point of forest management adaptation strategies in the context of drought-induced mortality.
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