9,995 research outputs found
Light bottom squark and gluino confront electroweak precision measurements
We address the compatibility of a light sbottom (mass 2\sim 5.5 \gev) and a
light gluino (mass 12\sim 16 \gev) with electroweak precision measurements.
Such light particles have been suggested to explain the observed excess in the
quark production cross section at the Tevatron. The electroweak observables
may be affected by the sbottom and gluino through the SUSY-QCD corrections to
the vertex. We examine, in addition to the SUSY-QCD corrections, the
electroweak corrections to the gauge boson propagators from the stop which are
allowed to be light from the SU(2) symmetry. We find that this scenario is
strongly disfavored from electroweak precision measurements unless the heavier
sbottom mass eigenstate is lighter than 180\gev and the left-right mixing in
the stop sector is sufficiently large. This implies that one of the stops
should be lighter than about 98\gev.Comment: 4 pages, revtex, 2 figures. Reference added, version to appear in
Phys.Rev.Let
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A minK-HERG complex regulates the cardiac potassium current I(Kr).
MinK is a widely expressed protein of relative molecular mass approximately 15K that forms potassium channels by aggregation with other membrane proteins. MinK governs ion channel activation, regulation by second messengers, and the function and structure of the ion conduction pathway. Association of minK with a channel protein known as KvLQT1 produces a voltage-gated outward K+ current (I[sK]) resembling the slow cardiac repolarization current (I[Ks]). HERG, a human homologue of the ether-a-go-go gene of the fruitfly Drosophila melanogaster, encodes a protein that produces the rapidly activating cardiac delayed rectifier (I[Kr]). These two potassium currents, I(Ks) and I(Kr), provide the principal repolarizing currents in cardiac myocytes for the termination of action potentials. Although heterologously expressed HERG channels are largely indistinguishable from native cardiac I(Kr), a role for minK in this current is suggested by the diminished I(Kr) in an atrial tumour line subjected to minK antisense suppression. Here we show that HERG and minK form a stable complex, and that this heteromultimerization regulates I(Kr) activity. MinK, through the formation of heteromeric channel complexes, is thus central to the control of the heart rate and rhythm
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A Comparison of Three Conditional Growth Percentile Methods: Student Growth Percentiles, Percentile Rank Residuals, and a Matching Method
This article provides a brief overview and comparison of three conditional growth percentile methods; student growth percentiles, percentile rank residuals, and a nonparametric matching method. These approaches seek to describe student growth in terms of the relative percentile ranking of a student in relationship to students that had the same profile of prior achievement. It is shown that even though the methods come from a similar conceptual foundation, the methods make different assumptions and use different models to estimate growth percentiles. Reading and Mathematics data from a large-scale assessment program are used to compare the growth percentile estimates in a practical setting. Results suggested that the methods often give somewhat similar results. However, the matching method tended to provide somewhat different estimates compared to the other approaches for students that had extreme scores on the prior year test. The implications of these results for large-scale state accountability programs are discussed. Accessed 5,254 times on https://pareonline.net from November 12, 2014 to December 31, 2019. For downloads from January 1, 2020 forward, please click on the PlumX Metrics link to the right
Plantes alimentaires d’intérêt médicinal utilisées par les Pygmées de la commune de Pissa (République Centrafricaine)
L’usage des plantes dans les thérapies traditionnelles et en alimentation est primordial pour les populations des zones tropicales en général et celles des zones forestières et principalement des Pygmées en particulier. Le présent article contribue à la connaissance des plantes alimentaires d’intérêt médicinal utilisées en milieu pygmée dans la commune de Pissa en Centrafrique. Suite aux enquêtes ethnobotaniques menées auprès des Pygmées, 31 espèces végétales ont été recensées. Elles sont réparties en 31 genres et 23 familles dont les plus riches du point de vue spécifique sont : les Annonaceae (3 espèces), les Euphorbiaceae (3 espèces), les Moraceae (2 espèces), les Sapotaceae (2 espèces) et les Ulmaceae (2 espèces). Les parties des plantes les plus utilisées en alimentation sont les fruits et les feuilles avec des proportions respectives de 40,62% et 37,50%. Cependant en thérapie traditionnelle, les feuilles et les écorces sont les plus utilisées (51, 35% pour les feuilles et 24,32% pour les écorces). Les pathologies associées à l’utilisation de ces plantes alimentaires fréquemment citées sont : les parasitoses, l’inflammation, les maux de ventre, les dermatoses et la toux.Mots clés : Plantes alimentaires, plantes médicinales, Pygmées, République Centrafricaine
Younger but sicker? : Cohort trends in disease accumulation among middle-aged and older adults in Scotland using health-linked data from the Scottish Longitudinal Study
This research was supported by the Economic and Social Research Council (ESRC) Centre for Population Change Connecting Generations research programme, grant number ES/W002116/1. This work was supported by the Academy of Medical Sciences, the Wellcome Trust, the Government Department of Business, Energy and Industrial Strategy, the British Heart Foundation Diabetes UK, and the Global Challenges Research Fund [Grant number SBF004\1093 awarded to Katherine Keenan]. The contribution from AM is funded by the National Institute for Health and Care Research (grant number NIHR202639).Background In the United Kingdom, rising prevalence of multimorbidity—the co-occurrence of two or more chronic conditions- is coinciding with stagnation in life expectancy. We investigate patterns of disease accumulation and how they vary by birth cohort, social and environmental inequalities in Scotland, a country which has long suffered from excess mortality and poorer health outcomes relative to its neighbours. Methods Using a dataset which links census data from 1991, 2001 and 2011 to disease registers and hospitalization data, we follow cohorts of adults aged 30–69 years for 18 years. We model physical and mental disease accumulation using linear mixed-effects models. Results Recent cohorts experience higher levels of chronic disease accumulation compared to their predecessors at the same ages. Moreover, in more recently born cohorts we observe socioeconomic status disparities emerging earlier in the life course, which widen over time and with every successive cohort. Patterns of chronic conditions are also changing, and the most common diseases suffered by later born cohorts are cancer, hypertension, asthma, drug and alcohol problems and depression. Conclusion We recommend policies which target prevention of chronic disease in working age adults, considering how and why certain conditions are becoming more prevalent across time and space.Peer reviewe
Comparing the impact of different thermal comfort constraints on a model-assisted control design process
In the design of supervisory controllers for managing energy in buildings, modelbased
control design approaches have recently attracted significant attention. The
control-design problem in these cases is typically posed as a constrained
minimization problem: given a simulation model acting as a surrogate of the
building, identify a controller that minimizes a cost function, say energy, subject to
the constraint that thermal comfort stays within acceptable levels. The use of a
thermal comfort model can be the means for estimating comfort so that the
mathematical programming problem can be formulated. In the present paper, we
investigate how the choice of thermal comfort model affects the quality of the
resulting controller. We consider a building simulated in EnergyPlus and design,
under the same conditions, controllers using three different thermal comfort models:
the model of Fanger, the two-node Pierce model, and the KSU two-node model. A
comparative study is performed to draw conclusions upon the effects that this
selection has with respect to the performance of the resulting controller
COPD and cardiovascular disease
COPD is one of the major public health problems in people aged 40 years or above. It is currently the 4th leading cause of death in the world and projected to be the 3rd leading cause of death by 2020. COPD and cardiac comorbidities are frequently associated. They share common risk factors, pathophysiological processes, signs and symptoms, and act synergistically as negative prognostic factors. Cardiac disease includes a broad spectrum of entities with distinct pathophysiology, treatment and prognosis. From an epidemiological point of view, patients with COPD are particularly vulnerable to cardiac disease. Indeed, mortality due to cardiac disease in patients with moderate COPD is higher than mortality related to respiratory failure. Guidelines reinforce that the control of comorbidities in COPD has a clear benefit over the potential risk associated with the majority of the drugs utilized. On the other hand, the true survival benefits of aggressive treatment of cardiac disease and COPD in patients with both conditions have still not been clarified. Given their relevance in terms of prevalence and prognosis, we will focus in this paper on the management of COPD patients with ischemic coronary disease, heart failure and dysrhythmia.Novartis Portugal
Novartisinfo:eu-repo/semantics/publishedVersio
A preliminary demonstration of transformation of functions through hierarchical relations
The current study focuses on the experimental analysis of hierarchical responding, and aims at analyzing some of the transformation of functions that take place at different levels of hierarchical categories. Ten university students participated. During Phase 1, four arbitrary stimuli were established as INCLUDES, BELONGS TO, SAME, and DIFFERENT relational cues, respectively. During Phase 2, three four-member equivalence classes were trained and tested (A1-B1-C1-D1; A2-B2-C2-D2; A3-B3-C3-D3). These equivalence classes constituted the bottom level of two hierarchical categories. The middle and top levels of the hierarchical categories were formed during Phase 3. The middle level was established by training hierarchical relations (INCLUDES and BELONGS TO) between novel stimuli X.1 and A1/B1; X. 2 and A2/B2; and Y and A3/B3. The top level was established by training hierarchical relations between X and X.1/X.2, and between Y and Y.1. During Phase 4, X.1 was established as always cold, D2 as always heavy and C3 as always sweet. During Phase 5 (Critical Test), six stimuli from both hierarchical categories (Y, X, C1, X.2, D3, C2) and a non-related stimulus (M) were tested for the transformation of functions. Nine of the ten participants responded correctly to the test. The implications and limitations of these findings, as well as lines for future research, are discussed
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α5β1-Integrin promotes tension-dependent mammary epithelial cell invasion by engaging the fibronectin synergy site.
Tumors are fibrotic and characterized by abundant, remodeled, and cross-linked collagen that stiffens the extracellular matrix stroma. The stiffened collagenous stroma fosters malignant transformation of the tissue by increasing tumor cell tension to promote focal adhesion formation and potentiate growth factor receptor signaling through kinase. Importantly, collagen cross-linking requires fibronectin (FN). Fibrotic tumors contain abundant FN, and tumor cells frequently up-regulate the FN receptor α5β1 integrin. Using transgenic and xenograft models and tunable two- and three-dimensional substrates, we show that FN-bound α5β1 integrin promotes tension-dependent malignant transformation through engagement of the synergy site that enhances integrin adhesion force. We determined that ligation of the synergy site of FN permits tumor cells to engage a zyxin-stabilized, vinculin-linked scaffold that facilitates nucleation of phosphatidylinositol (3,4,5)-triphosphate at the plasma membrane to enhance phosphoinositide 3-kinase (PI3K)-dependent tumor cell invasion. The data explain why rigid collagen fibrils potentiate PI3K activation to promote malignancy and offer a perspective regarding the consistent up-regulation of α5β1 integrin and FN in many tumors and their correlation with cancer aggression
Macroscopic effects of the spectral structure in turbulent flows
Two aspects of turbulent flows have been the subject of extensive, split
research efforts: macroscopic properties, such as the frictional drag
experienced by a flow past a wall, and the turbulent spectrum. The turbulent
spectrum may be said to represent the fabric of a turbulent state; in practice
it is a power law of exponent \alpha (the "spectral exponent") that gives the
revolving velocity of a turbulent fluctuation (or "eddy") of size s as a
function of s. The link, if any, between macroscopic properties and the
turbulent spectrum remains missing. Might it be found by contrasting the
frictional drag in flows with differing types of spectra? Here we perform
unprecedented measurements of the frictional drag in soap-film flows, where the
spectral exponent \alpha = 3 and compare the results with the frictional drag
in pipe flows, where the spectral exponent \alpha = 5/3. For moderate values of
the Reynolds number Re (a measure of the strength of the turbulence), we find
that in soap-film flows the frictional drag scales as Re^{-1/2}, whereas in
pipe flows the frictional drag scales as Re^{-1/4} . Each of these scalings may
be predicted from the attendant value of \alpha by using a new theory, in which
the frictional drag is explicitly linked to the turbulent spectrum. Our work
indicates that in turbulence, as in continuous phase transitions, macroscopic
properties are governed by the spectral structure of the fluctuations.Comment: 6 pages, 3 figure
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