338 research outputs found
WISER Deliverable D3.3-2: The importance of invertebrate spatial and temporal variation for ecological status classification for European lakes
European lakes are affected by many human induced disturbances. In principle, ecological
theories predict that the structure and functioning of benthic invertebrate assemblage (one of
the Biological Quality Elements following the Water Framework Directive, WFD
terminology) change in response to the level of disturbances, making this biological element
suitable for assessing the status and management of lake ecosystems. In practice, to set up
assessment systems based on invertebrates, we need to distiguish community changes that are
related to human pressures from those that are inherent natural variability. This task is
complicated by the fact that invertebrate communities inhabiting the littoral and the profundal
zones of lakes are constrained by different factors and respond unevenly to distinct human
disturbances. For example it is not clear yet how the invertebrates assemblages respond to
watershed and shoreline alterations, nor the relative importance of spatial and temporal
factors on assemblage dynamics and relative bioindicator values of taxa, the habitat
constraints on species traits and other taxonomic and methodological limitations.
The current lack of knowledge of basic features of invertebrate temporal and spatial variations
is limiting the fulfillment of the EU-wide intercalibration of lake ecological quality
assessment systems in Europe, and thus compromising the basis for setting the environmental
objectives as required by the WFD. The aim of this deliverable is to provide a contribution
towards the understanding of basic sources of spatial and temporal variation of lake
invertebrate assemblages. The report is structured around selected case studies, manly
involving the analysis of existing datasets collated within WISER. The case studies come
from different European lake types in the Northern, Central, Alpine and Mediterranean
regions. All chapters have an obvious applied objective and our aim is to provide to those
dealing with WFD implementation at various levels useful information to consider when
designing monitoring programs and / or invertebrate-based classification systems
A critical analysis of the role of testosterone in erectile function: From pathophysiology to treatment - A systematic review
Context: Androgen modulation of erectile function (EF) is widely accepted. However, the use of testosterone replacement therapy (TRT) in men with erectile dysfunction (ED) has generated an unprecedented debate. Objective: To summarize the relevant data on the incidence, diagnosis, and management of ED coexisting with hypogonadism and to develop a pathophysiology-based treatment algorithm. Evidence acquisition: We reviewed the relevant medical literature, with a particular emphasis on original molecular studies, prospective observational data, and randomized controlled trials performed in the past 20 yr. Evidence synthesis: Testosterone modulates nearly every component involved in EF, from pelvic ganglions to smooth muscle and the endothelial cells of the corpora cavernosa. It also regulates the timing of the erectile process as a function of sexual desire, coordinating penile erection with sex. Epidemiologic studies confirm the significant overlap of hypogonadism and ED; however, most guidelines do not consider the differential diagnosis of hypogonadism or the relevance of subclinical disease. Various clinical tools can help the physician to assess and restore androgen levels in men with ED. Special attention is given to fertility-sparing treatments, due to the increasing number of older men desiring fatherhood. The simultaneous use of phosphodiesterase type 5 inhibitors (PDE5-Is) and TRT has recently been questioned. Originally proposed as a salvage therapy for nonresponders to PDE5-Is, this approach has been inappropriately transformed into a combination therapy. Clinical data are consistent when reinterpreted in the proper framework, whereas molecular evidence remains controversial. Conclusions: A body of molecular and clinical evidence supports the use of TRT in hypogonadal patients with ED, although the benefit-risk ratio is uncertain in advanced age. Critical appraisal of this evidence enabled the development of a pathophysiology-oriented algorithm designed to avoid inappropriate treatments and support whether to start with TRT, PDE5-I only, or both. Apparently divergent findings are reconciled when TRT is correctly indicated. An improved diagnosis and individualized management is desirable in light of the many available options. © 2013 European Association of Urology
Physics-Based Mixed-Mode Reverse Recovery Modeling And Optimization Of Si PiN And MPS Fast Recovery Diodes
The paper presents the results of the application of physics-based mixed-mode simulations to the analysis and optimization of the reverse recovery for Si-based fast recovery diodes (FREDs) using Platinum (Pt) lifetime killing. The trap model parameters are extracted from Deep Level Transient Spectroscopy (DLTS) characterization. The model is validated against experimental characterization carried out on the current International Rectifier (IR) FRED PiN technology. Improved designs, using emitter control efficiency and merged PiN-Schottky structures, are analyzed. Comparison between simulated and measured results are presente
Simvastatin improves the sexual health-related quality of life in men aged 40 years and over with erectile dysfunction : Additional data from the Erectile Dysfunction and Statin trial
© 2014 Trivedi et al. This is an Open Access article distributed under the terms of the Creative Commons Attribution License http://creativecommons.org/licenses/by/2.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly credited.Background: Erectile dysfunction is prevalent in men over 40 years, affecting their quality of life and that of their partners. The aims of this study were:a)To evaluate the internal reliability of the male erectile dysfunction specific quality of life (MED-QoL) scale and explore its factor structure.b)To evaluate the effect of simvastatin on subscales of the MED-QoL in men over forty years with erectile dysfunction. Methods: This is a double blind randomised controlled trial of 40 mg simvastatin or placebo given once daily for six months to men over forty years with untreated erectile dysfunction, who were not at high cardiovascular risk and were not on anti-hypertensive or lipid-lowering medication. 173 eligible men were recruited from 10 general practices in East of England. Data were collected at two points over 30 weeks. We report on the factor structure of MED-QoL, the internal reliability of the scale and the derived subscales, and the effect of simvastatin on MED-QoL subscales. Results: An initial analysis of the MED-QoL items suggested that a number of items should be removed (MED-QoL-R). Exploratory factor analysis identified three subscales within the MED-QoL-R which accounted for 96% of the variance, related to feelings of Control, initiating Intimacy, and Emotional response to erectile dysfunction. The alpha value for the revised scale (MED-Qol-R) was >0.95 and exceeded .82 for each subscale. Regression analysis showed that patients in the placebo group experienced a significantly reduced feeling of Control over erectile dysfunction than those in the statin group. Those in the placebo group had significantly lower Emotional response than those in the statin group at the close of trial, but there was no significant treatment effect on Intimacy. Conclusions: Our revised MED-QoL-R identified three subscales. Secondary analysis showed a significant improvement in sexual health related quality of life, specifically in relation to perception of control and emotional health in men with untreated erectile dysfunction given 40 mg simvastatin for six months. Trial registration: Current Controlled Trials ISRCTN66772971.Peer reviewe
Large genomic rearrangements in the CFTR gene contribute to CBAVD
<p>Abstract</p> <p>Background</p> <p>By performing extensive scanning of whole coding and flanking sequences of the <it>CFTR (Cystic Fibrosis Transmembrane Conductance Regulator</it>) gene, we had previously identified point mutations in 167 out of 182 (91.7%) males with isolated congenital bilateral absence of the vas deferens (CBAVD). Conventional PCR-based methods of mutation analysis do not detect gross DNA lesions. In this study, we looked for large rearrangements within the whole <it>CFTR </it>locus in the 32 CBAVD patients with only one or no mutation.</p> <p>Methods</p> <p>We developed a semi-quantitative fluorescent PCR assay (SQF-PCR), which relies on the comparison of the fluorescent profiles of multiplex PCR fragments obtained from different DNA samples. We confirmed the gross alterations by junction fragment amplification and identified their breakpoints by direct sequencing.</p> <p>Results</p> <p>We detected two large genomic heterozygous deletions, one encompassing exon 2 (c.54-5811_c.164+2186del8108ins182) [or <it>CFTRdele2</it>], the other removing exons 22 to 24 (c.3964-3890_c.4443+3143del9454ins5) [or <it>CFTRdele 22_24</it>], in two males carrying a typical CBAVD mutation on the other parental <it>CFTR </it>allele. We present the first bioinformatic tool for exon phasing of the <it>CFTR </it>gene, which can help to rename the exons and the nomenclature of small mutations according to international recommendations and to predict the consequence of large rearrangements on the open reading frame.</p> <p>Conclusion</p> <p>Identification of large rearrangements further expands the <it>CFTR </it>mutational spectrum in CBAVD and should now be systematically investigated. We have designed a simple test to specifically detect the presence or absence of the two rearrangements identified in this study.</p
Superconducting Effects in Optimization of Magnetic Penetration Thermometers for X-ray Microcalorimeters
Like MMCs, MPTs enable high energy microcalorimeters with zero bias power dissipation and potential resolution < 1 eV. MPTs can provide d(phi)/dT as large as 1000 (Phi)(sub 0)/K, with no excess noise, thereby reducing the importance of SQUID noise. Long coherence length in a Type-I superconducting MoAu film offers multiple advantages for efficient flux expulsion in MPT. Region of steepest d(phi)/dT is the Meissner effect in the small device; flux is expelled/penetrates to minimize free energy. Steepness of transition can be engineered with choice of film thickness and coil pitch relative to lambda(sub eff)(0), ratio of T/T(sub c), and bias circuit inductance
The fundamental pro-groupoid of an affine 2-scheme
A natural question in the theory of Tannakian categories is: What if you
don't remember \Forget? Working over an arbitrary commutative ring , we
prove that an answer to this question is given by the functor represented by
the \'etale fundamental groupoid \pi_1(\spec(R)), i.e.\ the separable
absolute Galois group of when it is a field. This gives a new definition
for \'etale \pi_1(\spec(R)) in terms of the category of -modules rather
than the category of \'etale covers. More generally, we introduce a new notion
of "commutative 2-ring" that includes both Grothendieck topoi and symmetric
monoidal categories of modules, and define a notion of for the
corresponding "affine 2-schemes." These results help to simplify and clarify
some of the peculiarities of the \'etale fundamental group. For example,
\'etale fundamental groups are not "true" groups but only profinite groups, and
one cannot hope to recover more: the "Tannakian" functor represented by the
\'etale fundamental group of a scheme preserves finite products but not all
products.Comment: 46 pages + bibliography. Diagrams drawn in Tik
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