59,046 research outputs found
Propositional Encoding of Constraints over Tree-Shaped Data
We present a functional programming language for specifying constraints over
tree-shaped data. The language allows for Haskell-like algebraic data types and
pattern matching. Our constraint compiler CO4 translates these programs into
satisfiability problems in propositional logic. We present an application from
the area of automated analysis of (non-)termination of rewrite systems
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Levothyroxine effects on depressive symptoms and limbic glucose metabolism in bipolar disorder: a randomized, placebo-controlled positron emission tomography study.
Adding supraphysiologic doses of levothyroxine (L-T4) to standard treatment for bipolar depression shows promise, but the mechanisms underlying clinical improvement are unknown. In a previous pilot study, L-T4 treatment reduced depression scores and activity within the anterior limbic network. Here we extended this work in a randomized, double-blind, placebo-controlled study of patients with bipolar depression. Cerebral glucose metabolism was assessed with positron emission tomography and [F-18]fluorodeoxyglucose before and after 6 weeks of treatment with L-T4 (n=15) or placebo (n=10) in 12 volumes of interest (VOIs): the bilateral thalamus, amygdala, hippocampus, dorsal striatum and ventral striatum, and midline cerebellar vermis and subgenual cingulate cortex. Radioactivity in the VOIs, normalized to whole-brain radioactivity was taken as a surrogate index of glucose metabolism, and markers of thyroid function were assayed. Changes in brain activity and their association with clinical response were assessed using statistical parametric mapping. Adjunctive L-T4 treatment produced a significant decline in depression scores during the 6-week treatment. In patients treated with L-T4, we found a significant decrease in regional activity at P<0.05 after Bonferroni correction in the left thalamus, right amygdala, right hippocampus, left ventral striatum and the right dorsal striatum. Decreases in the left thalamus, left dorsal striatum and the subgenual cingulate were correlated with a reduction in depression scores (P<0.05 after Bonferroni correction). Placebo treatment was associated with a significant decrease in activity only in the right amygdala, and no region had a change in activity that was correlated with change in depression scores. The groups differed significantly in the relationship between the changes in depression scores and in activity in the thalamus bilaterally and the left ventral striatum. The findings provide evidence that administration of supraphysiologic thyroid hormone improves depressive symptoms in patients with bipolar disorder by modulating function in components of the anterior limbic network
Uterine spiral artery remodeling involves endothelial apoptosis induced by extravillous trophoblasts through Fas/FasL interactions.
Objective— Invasion of uterine spiral arteries by extravillous trophoblasts in the first trimester of pregnancy results in loss of endothelial and musculoelastic layers. This remodeling is crucial for an adequate blood supply to the fetus with a failure to remodel implicated in the etiology of the hypertensive disorder preeclampsia. The mechanism by which trophoblasts induce this key process is unknown. This study gives the first insights into the potential mechanisms involved.
Methods and Results— Spiral arteries were dissected from nonplacental bed biopsies obtained at Caesarean section, and a novel model was used to mimic in vivo events. Arteries were cultured with trophoblasts in the lumen, and apoptotic changes in the endothelial layer were detected after 20 hours, leading to loss of endothelium by 96 hours. In vitro, coculture experiments showed that trophoblasts stimulated apoptosis of primary decidual endothelial cells and an endothelial cell line. This was blocked by caspase inhibition and NOK2, a FasL blocking antibody. NOK2 also abrogated trophoblast-induced endothelial apoptosis in the vessel model.
Conclusions— Extravillous trophoblast induction of endothelial apoptosis is a possible mechanism by which the endothelium is removed, and vascular remodeling may occur in uterine spiral arteries. Fas/FasL interactions have an important role in trophoblast-induced endothelial apoptosis
Developing reusable.NET software components
© 2014 The Science and Information (SAI) Organization. Software Development with reuse and for reuse is the foundation of CBSE (Component based software engineering) which allow faster development at lower cost and better usability. A reusable software component works as a plug and play device, which abstract the software complexity and increase performance. Software reuse guidelines have been addressing the issue of capturing best practices, for a long while software industry has collected the enormous wealth of knowledge, experience, domain expertise, design principals & heuristics, hypothesis, algorithms, and experimental results. However, there is no rock solid and mature software component development guidelines defined for the current technologies such as.NET. This paper presents reuse guidelines based framework (known as.NET Reuse Guider) for guidelines based component development for reuse in.NET family. We have demonstrated our approach by designing a binary component as part of development for reuse based on our own.NET Reuse Guider framework. This paper also provides a number reuse analysis and metrics and a prototype component guider tool which sits on top of the.NET architecture with built-in software development & reuse knowledge
Accretion Disc Theory: From the Standard Model Until Advection
Accretion disc theory was first developed as a theory with the local heat
balance, where the whole energy produced by a viscous heating was emitted to
the sides of the disc. One of the most important new invention of this theory
was a phenomenological treatment of the turbulent viscosity, known as ''alpha''
prescription, when the (r) component of the stress tensor was
approximated by ( P) with a unknown constant . This
prescription played the role in the accretion disc theory as well important as
the mixing-length theory of convection for stellar evolution. Sources of
turbulence in the accretion disc are discussed, including nonlinear
hydrodynamical turbulence, convection and magnetic field role. In parallel to
the optically thick geometrically thin accretion disc models, a new branch of
the optically thin accretion disc models was discovered, with a larger
thickness for the same total luminosity. The choice between these solutions
should be done of the base of a stability analysis. The ideas underlying the
necessity to include advection into the accretion disc theory are presented and
first models with advection are reviewed. The present status of the solution
for a low-luminous optically thin accretion disc model with advection is
discussed and the limits for an advection dominated accretion flows (ADAF)
imposed by the presence of magnetic field are analysed.Comment: Roceeding of the Int. Workshop "Observational Evidence for Black
Holes in the Universe". Calcutta, 11-17 January 1998. Kluwer Acad. Pu
No Detectable Fertility Benefit from a Single Additional Mating in Wild Stalk-Eyed Flies
Background: Multiple mating by female insects is widespread, and the explanation(s) for repeated mating by females has been the subject of much discussion. Females may profit from mating multiply through direct material benefits that increase their own reproductive output, or indirect genetic benefits that increase offspring fitness. One particular direct benefit that has attracted significant attention is that of fertility assurance, as females often need to mate multiply to achieve high fertility. This hypothesis has never been tested in a wild insect population.Methodology/Principal Findings: Female Malaysian stalk-eyed flies (Teleopsis dalmanni) mate repeatedly during their lifetime, and have been shown to be sperm limited under both laboratory and field conditions. Here we ask whether receiving an additional mating alleviates sperm limitation in wild females. In our experiment one group of females received a single additional mating, while a control group received an interrupted, and therefore unsuccessful, mating. Females that received an additional mating did not lay more fertilised eggs in total, nor did they lay proportionately more fertilised eggs. Female fertility declined significantly through time, demonstrating that females were sperm limited. However, receipt of an additional mating did not significantly alter the rate of this decline.Conclusions/Significance: Our data suggest that the fertility consequences of a single additional mating were small. We discuss this effect (or lack thereof), and suggest that it is likely to be attributed to small ejaculate size, a high proportion of failed copulations, and the presence of X-linked meiotic drive in this species
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