1,042 research outputs found
Changes in species composition in alpine snowbeds with climate change inferred from small-scale spatial patterns
Alpine snowbeds are characterised by a very short growing season. However, the length of the snow-free period is increasingly prolonged due to climate change, so that snowbeds become susceptible to invasions from neighbouring alpine meadow communities. We hypothesised that spatial distribution of species generated by plant interactions may indicate whether snowbed species will coexist with or will be out-competed by invading alpine species &ndash; spatial aggregation or segregation will point to coexistence or competitive exclusion, respectively. We tested this hypothesis in snowbeds of the Swiss Alps using the variance ratio statistics. We focused on the relationships between dominant snowbed species, subordinate snowbed species, and potentially invading alpine grassland species. Subordinate snowbed species were generally spatially aggregated with each other, but were segregated from alpine grassland species. <br><br> Competition between alpine grassland and subordinate snowbed species may have caused this segregation. Segregation between these species groups increased with earlier snowmelt, suggesting an increasing importance of competition with climate change. Further, a dominant snowbed species (<i>Alchemilla pentaphyllea</i>) was spatially aggregated with subordinate snowbed species, while two other dominants (<i>Gnaphalium supinum</i> and <i>Salix herbacea</i>) showed aggregated patterns with alpine grassland species. These dominant species are known to show distinct microhabitat preferences suggesting the existence of hidden microhabitats with different susceptibility to invaders. <br><br> These results allow us to suggest that alpine snowbed areas are likely to be reduced as a consequence of climate change and that invading species from nearby alpine grasslands could outcompete subordinate snowbed species. On the other hand, microhabitats dominated by <i>Gnaphalium</i> or <i>Salix</i> seem to be particularly prone to invasions by non-snowbed species
Transcranial magnetic stimulation in depression--lessons from the multicentre trials
Looking at novelties and advances in medicine in particular in the treatment of major depressive disorder no principally new antidepressant treatment strategy has been established in clinical routine in the last fifty years. However, regarding the considerable issue of treatment resistance in depression, new therapeutic strategies are urgently required. In this context, repetitive transcranial magnetic stimulation above the dorsolateral prefrontal cortex has been proposed as a potential new treatment option for depression; furthermore, in October 2008 a first rTMS-device (NeuroStar TMS Therapy System™) was approved by the FDA for the treatment of treatment resistant major refractory depression in adults. Yet, despite now nearly two decades of research in this field, no final answer concerning its validity for antidepressant treatment in the clinical practice is given. Numerous studies with small sample sizes and heterogeneous designs have been performed in this field yielding to different results. These were subjected to meta-analyses, assessing the antidepressant effect of rTMS, which are briefly summarized in this article. Further, multicentre-trials with larger numbers of patients were performed, which are presented and critically discussed here in more detail. This short review shall thus provide an overview of the current status of knowledge concerning rTMS in depression and it also provides some recommendations for future research in this field
Simultaneous Embeddings with Few Bends and Crossings
A simultaneous embedding with fixed edges (SEFE) of two planar graphs and
is a pair of plane drawings of and that coincide when restricted to
the common vertices and edges of and . We show that whenever and
admit a SEFE, they also admit a SEFE in which every edge is a polygonal curve
with few bends and every pair of edges has few crossings. Specifically: (1) if
and are trees then one bend per edge and four crossings per edge pair
suffice (and one bend per edge is sometimes necessary), (2) if is a planar
graph and is a tree then six bends per edge and eight crossings per edge
pair suffice, and (3) if and are planar graphs then six bends per edge
and sixteen crossings per edge pair suffice. Our results improve on a paper by
Grilli et al. (GD'14), which proves that nine bends per edge suffice, and on a
paper by Chan et al. (GD'14), which proves that twenty-four crossings per edge
pair suffice.Comment: Full version of the paper "Simultaneous Embeddings with Few Bends and
Crossings" accepted at GD '1
Welding-base metal investigation Final report, 27 Jun. 1964 - 28 Jul. 1965
Weld defects associated with aluminum alloys - monitoring weld shielding gas purit
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Resources for Texas Sexual Assault Survivors: Inventory and Survey Findings on Services, Gaps, and Accessibility
Texas is a leader among states on the issue of sexual assault, and has promoted and funded
the study of sexual violence as well as created the Sexual Assault Survivors’ Task Force
(SASTF) through the Office of the Texas Governor (OOG). Sexual assault is clearly
established as a public health problem affecting 6.3 million women and men in the state, or
33.2% of adult Texans over their lifetime.1 This statistic comes from thorough research by
the Institute on Domestic Violence & Sexual Assault (IDVSA) at The University of Texas at
Austin on the prevalence and impact of sexual assault on Texans, service providers, and the
social and economic system at large.
The bipartisan passage of HB 1590 (86R)
B
signifies a continued commitment by Texas
lawmakers to serve sexual assault survivors. Lawmakers and Texans alike acknowledge the
seriousness of sexual assault crimes. With the research findings derived from this project,
survivors and their families, professionals supporting survivors, and lawmakers can better
see the landscape of resources, service provision gaps, and unmet needs across our state.
The specific project aims were to:
• Inventory the sexual assault services available in Texas.
• Assess sexual assault survivors’ needs by region for the 11 Texas regions.
• Develop a sexual assault services resource inventory.
IDVSA accomplished those aims by:
• Developing and implementing a statewide survey to a broad and diverse set of
providers who serve survivors of sexual violence.
• Conducting a collaborative analysis of the survey findings with a specific focus on
service availability and service gaps, and presenting those in this report to the OOG.
• Developing an HB 1590 Inventory List of the resources available to survivors across
the state and delivering it to the OOG to inform the creation of a comprehensive
statewide service directory in the futureInstitute on Domestic Violence and Sexual Assault (IDVSA
Characteristics of Welding Fume Aerosol Investigated in Three Swedish Workshops
Potentially high human exposures to nanometer sized airborne particles occur due to welding and other thermal processes in industrial environments. Detailed field measurements of physical and chemical particle characteristics were performed in three work-shops in Sweden. Measurements were performed both in the plume 5-20 cm above the welding point and in the background air (more than 5 m away from the nearest known particle source). Particle number and mass concentrations were measured on-line. A low pressure impactor was used for size-resolved chemical particle composition. The in-plume measurements generated the chemical signatures for different welding processes. These signatures were then used to identify contributions from various processes to the particle concentrations in different size classes. The background number and mass concentrations increased by more than an order of magnitude during intense activities in the work-shops compared to low activities during breaks
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