485 research outputs found
Subglacial tunnel valleys in the Alpine foreland: an example from Bern, Switzerland
The morphology of the Alpine and adjacent landscapes is directly related to glacial erosion and associated sediment transport. Here we report the effects of glacio-hydrologic erosion on bedrock topography in the Swiss Plateau. Specifically, we identify the presence of subsurface valleys beneath the city of Bern and discuss their genesis. Stratigraphic investigations of more than 4,000 borehole data within a 430km2-large area reveal the presence of a network of >200m-deep and 1,000m-wide valleys. They are flat floored with steep sided walls and are filled by Quaternary glacial deposits. The central valley beneath Bern is straight and oriented towards the NNW, with valley flanks more than 20° steep. The valley bottom has an irregular undulating profile along the thalweg, with differences between sills and hollows higher than 50-100m over a reach of 4km length. Approximately 500m high bedrock highlands flank the valley network. The highlands are dissected by up to 80m-deep and 500m-broad hanging valleys that currently drain away from the axis of the main valley. We interpret the valleys beneath the city of Bern to be a tunnel valley network which originated from subglacial erosion by melt water. The highland valleys served as proglacial meltwater paths and are hanging with respect to the trunk system, indicating that these incipient highland systems as well as the main gorge beneath Bern formed by glacial melt water under pressur
How attribution influences aggression: answers to an old question by using an implicit measure of anger
The present study investigated how aggressive reactions to frustration are influenced by attributional processes. In particular, we examined how the information that another person did not intend a frustration affects anger and aggression. Previous research was inconclusive if attribution to unintentionality decreases anger and aggressive impulses or if it increases the control of aggressive impulses resulting in a selective decrease of aggressive reactions that are controllable. To test these assumptions, two thirds of participants were frustrated by negative evaluations that were paired with aversive sounds from an ostensible team partner. The remaining participants received positive evaluations that were paired with pleasant sounds. Then, half of the frustrated participants obtained a message suggesting that their partner had confused the response scale and had actually meant to deliver an opposite evaluation. This apologizing information was effective in decreasing subsequent aggressive behavior but not in reducing anger as assessed by an implicit measure. This finding is in line with the notion that attribution to unintentionality leads to control of aggressive impulses. We conclude that such attributions influence aggressive behavior mainly via reflective pathways, while impulsive processes remain largely unaffected
Overdeepenings in the Swiss plateau: U-shaped geometries underlain by inner gorges
We investigated the mechanisms leading to the formation of tunnel valleys in the Swiss foreland near Bern. We proceeded through producing 3D maps of the bedrock topography based on drillhole information and a new gravimetric survey combined with modelling. In this context, the combination of information about the densities of the sedimentary fill and of the bedrock, together with published borehole data and the results of gravity surveys along 11 profiles across the valleys, served as input for the application of our 3D gravity modelling software referred to as PRISMA. This ultimately allowed us to model the gravity effect of the Quaternary fill of the overdeepenings and to produce cross-sectional geometries of these troughs. The results show that 2–3 km upstream of the city of Bern, the overdeepenings are approximately 3 km wide. They are characterized by steep to oversteepened lateral flanks and a wide flat base, which we consider as a U-shaped cross-sectional geometry. There, the maximum residual gravity anomaly ranges between − 3 to − 4 mGal for the Aare valley, which is the main overdeepening of the region. Modelling shows that this corresponds to a depression, which reaches a depth of c. 300 m a.s.l. Farther downstream approaching Bern, the erosional trough narrows by c. 1 km, and the base gets shallower by c. 100 m as revealed by drillings. This is supported by the results of our gravity surveys, which disclose a lower maximum gravity effect
of c. − 0.8 to − 1.3 mGal. Interestingly, in the Bern city area, these shallow troughs with maximum gravity anomalies ranging from − 1.4 to − 1.8 mGal are underlain by one or multiple inner gorges, which are at least 100 m deep (based on drilling information) and only a few tens of meters wide (disclosed by gravity modelling). At the downstream end of the Bern area, we observe that the trough widens from 2 km at the northern border of Bern to c. 4 km approximately 2 km farther downstream, while the bottom still reaches c. 300 to 200 m a.s.l. Our gravity survey implies
that this change is associated with an increase in the maximum residual anomaly, reaching values of − 2.5 mGal. Interestingly, the overdeepening’s cross-sectional geometry in this area has steeply dipping flanks converging to a narrow base, which we consider as V-shaped. We attribute this shape to erosion by water either underneath or at the snout of a glacier, forming a gorge. This narrow bedrock depression was subsequently widened by glacial carving. In this context, strong glacial erosion upstream of the Bern area appears to have overprinted these traces. In contrast,
beneath the city of Bern and farther downstream these V-shaped features have been preserved. Available chronological data suggest that the formation of this gorge occurred prior to MIS 8 and possibly during the aftermath of one of the largest glaciations when large fluxes of meltwater resulted in the fluvial carving into the bedrock
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Individual common variants exert weak effects on the risk for autism spectrum disorders.
While it is apparent that rare variation can play an important role in the genetic architecture of autism spectrum disorders (ASDs), the contribution of common variation to the risk of developing ASD is less clear. To produce a more comprehensive picture, we report Stage 2 of the Autism Genome Project genome-wide association study, adding 1301 ASD families and bringing the total to 2705 families analysed (Stages 1 and 2). In addition to evaluating the association of individual single nucleotide polymorphisms (SNPs), we also sought evidence that common variants, en masse, might affect the risk. Despite genotyping over a million SNPs covering the genome, no single SNP shows significant association with ASD or selected phenotypes at a genome-wide level. The SNP that achieves the smallest P-value from secondary analyses is rs1718101. It falls in CNTNAP2, a gene previously implicated in susceptibility for ASD. This SNP also shows modest association with age of word/phrase acquisition in ASD subjects, of interest because features of language development are also associated with other variation in CNTNAP2. In contrast, allele scores derived from the transmission of common alleles to Stage 1 cases significantly predict case status in the independent Stage 2 sample. Despite being significant, the variance explained by these allele scores was small (Vm< 1%). Based on results from individual SNPs and their en masse effect on risk, as inferred from the allele score results, it is reasonable to conclude that common variants affect the risk for ASD but their individual effects are modest
Diskriminiert – Abgelehnt – Vergessen: Kinder afro-amerikanischer GIs und österreichischer Frauen nach 1945. Ein Projektbericht
Gestational Diabetes: Physical Activity Before Pregnancy and Its Influence on the Cardiovascular System
Objectives:Gestational diabetes mellitus (GDM) is a common complication in pregnancy, affecting around 14% of all pregnancies each year. It will likely further increase, as obesity becomes more prevalent. The impact of GDM on cardiovascular changes in pregnant women and her child is still unclear. The aim of the study was to measure the effects of physical activity before pregnancy on the cardiovascular system in patients with GDM in pregnancy. Methods:Two hundred and six pregnant women were included in this observational study. All participants were recruited at the tertiary level teaching University Hospital "Klinikum rechts der Isar" between 28 and 32 weeks gestation. Questionnaires dealing with pre-pregnancy daily and physical activity (PA) were evaluated. The cardiovascular status of the mothers included measurements of the intima-media thickness (IMT) of the carotid arteries. PA level was performed with a standardized 6-min-walking-test. Results:Ninety-nine women with GDM with a mean age of 33.84 (+/- 4.7) years were examined. One hundred seven healthy pregnant women aged 32.6 (+/- 4.2) years served as controls. The mean weight in the study group was 73.0 (+/- 20.3) kg and 61.7 (+/- 9.5) kg in the control group. Based on the higher weight in the study group, the Body Mass Index (BMI) was also significantly higher than in the control group (26.3 +/- 7.1 vs. 21.6 +/- 3;p< 0.001). The frequency of PA was significantly higher in the control group (p< 0.001). The objective fitness level was worse in pregnant women with GDM compared to healthy controls (472 vs. 523 m,p< 0.001). PA before and during pregnancy was less performed in the study group (86 vs. 64.5%,p= 0.002;69 vs. 45.7%,p= 0.003). Women who were physically inactive before pregnancy had a 3-times higher risk to develop GDM compared to active women (OR = 2.67). The IMT was significantly thicker in the study group (0.48 +/- 0.042 mm vs. 0.45 +/- 0.042) mm;p= 0.006). Conclusion:Physical activity before pregnancy and a lower initial weight reduces the risk of developing GDM and cardiovascular risk factors in pregnancy. The development of prevention programs is certainly necessary
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