3,703 research outputs found
Determinants of Export Performance of Indian Firms – A Strategic Perspective
Macroeconomic policy reforms initiated in India since 1991 have brought about a significant improvement in the export performance of Indian firms. This paper examines the export performance of firms with the help of balance sheet data of 557 firms for the years 1980-81 to 1995-96. Applying panel Tobit model, it explains the improved export performance through changes in various firm level variables as well as economic environmental factors derived from existing literature on experiences of different countries. The paper also draws certain strategic and policy implications likely to be relevant for emerging economies from its findings on India.
Reduced neurosteroid potentiation of GABAA receptors in epilepsy and depolarized hippocampal neurons
OBJECTIVE: Neurosteroids regulate neuronal excitability by potentiating γ-aminobutyric acid type-A receptors (GABARs). In animal models of temporal lobe epilepsy, the neurosteroid sensitivity of GABARs is diminished and GABAR subunit composition is altered. We tested whether similar changes occur in patients with epilepsy and if depolarization-induced increases in neuronal activity can replicate this effect.
METHODS: We determined GABAR α4 subunit expression in cortical tissue resected from pediatric epilepsy patients. Modulation of human GABARs by allopregnanolone and Ro15-4513 was measured in Xenopus oocytes using whole-cell patch clamp. To extend the findings obtained using tissue from epilepsy patients, we evaluated GABAR expression and modulation by allopregnanolone and Ro15-4513 in cultured rat hippocampal neurons exposed to high extracellular potassium (HK) to increase neuronal activity.
RESULTS: Expression of α4 subunits was increased in pediatric cortical epilepsy specimens encompassing multiple pathologies. The potentiation of GABA-evoked currents by the neurosteroid allopregnanolone was decreased in Xenopus oocytes expressing GABARs isolated from epilepsy patients. Furthermore, receptors isolated from epilepsy but not control tissue were sensitive to potentiation by Ro15-4513, indicating higher expression of α
INTERPRETATION: These findings suggest that seizure activity-induced upregulation of
Does clinical management improve outcomes following self-Harm? Results from the multicentre study of self-harm in England
Background
Evidence to guide clinical management of self-harm is sparse, trials have recruited selected samples, and psychological treatments that are suggested in guidelines may not be available in routine practice.
Aims
To examine how the management that patients receive in hospital relates to subsequent outcome.
Methods
We identified episodes of self-harm presenting to three UK centres (Derby, Manchester, Oxford) over a 10 year period (2000 to 2009). We used established data collection systems to investigate the relationship between four aspects of management (psychosocial assessment, medical admission, psychiatric admission, referral for specialist mental health follow up) and repetition of self-harm within 12 months, adjusted for differences in baseline demographic and clinical characteristics.
Results
35,938 individuals presented with self-harm during the study period. In two of the three centres, receiving a psychosocial assessment was associated with a 40% lower risk of repetition, Hazard Ratios (95% CIs): Centre A 0.99 (0.90–1.09); Centre B 0.59 (0.48–0.74); Centre C 0.59 (0.52–0.68). There was little indication that the apparent protective effects were mediated through referral and follow up arrangements. The association between psychosocial assessment and a reduced risk of repetition appeared to be least evident in those from the most deprived areas.
Conclusion
These findings add to the growing body of evidence that thorough assessment is central to the management of self-harm, but further work is needed to elucidate the possible mechanisms and explore the effects in different clinical subgroups
A combined experimental and computational fluid dynamics analysis of the dynamics of drop formation
This article presents a complementary experimental and computational investigation of the effect of viscosity and flowrate on the dynamics of drop formation in the dripping mode. In contrast to previous studies, numerical simulations are performed with two popular commercial computational fluid dynamics (CFD) packages, CFX and FLOW-3D, both of which employ the volume of fluid (VOF) method. Comparison with previously published experimental and computational data and new experimental results reported here highlight the capabilities and limitations of the aforementioned packages
Flexible copper-indium-diselenide films and devices for space applications
With the ever increasing demands on space power systems, it is imperative that low cost, lightweight, reliable photovoltaics be developed. One avenue of pursuit for future space power applications is the use of low cost, lightweight flexible PV cells and arrays. Most work in this area assumes the use of flexible amorphous silicon (a-Si), despite its inherent instability and low efficiencies. However, polycrystalline thin film PV such as copper-indium-diselenide (CIS) are inherently more stable and exhibit better performance than a-Si. Furthermore, preliminary data indicate that CIS also offers exciting properties with respect to space applications. However, CIS has only heretofore only produced on rigid substrates. The implications of flexible CIS upon present and future space power platforms was explored. Results indicate that space qualified CIS can dramatically reduce the cost of PV, and in most cases, can be substituted for silicon (Si) based on end-of-life (EOL) estimations. Furthermore, where cost is a prime consideration, CIS can become cost effective than gallium arsenide (GaAs) in some applications. Second, investigations into thin film deposition on flexible substrates were made, and data from these tests indicate that fabrication of flexible CIS devices is feasible. Finally, data is also presented on preliminary TCO/CdS/CuInSe2/Mo devices
Evidence in support of the International Association of Diabetes in Pregnancy study groups' criteria for diagnosing gestational diabetes mellitus worldwide in 2019
Gestational diabetes mellitus, the most frequent medical complication of pregnancy, affects 5-6% of women in the United States with the use of the currently predominant Carpenter-Coustan criteria, which still represent the preferred approach of the American College of Obstetricians and Gynecologists. Alternative criteria proposed by the International Association of Diabetes in Pregnancy Study Groups would likely increase gestational diabetes mellitus prevalence to 15-20%, because of both a 1-step testing policy and the requirement for only 1 elevated glucose value for diagnosis. Increasing gestational diabetes mellitus prevalence relates to older maternal age and the increasing prevalence of overweight and obesity. This increased gestational diabetes mellitus prevalence is consistent with 29.3% prevalence of prediabetes and 4.5% prevalence of known diabetes outside pregnancy in US adults from 20-44 years of age. Gestational diabetes mellitus according to the International Association of Diabetes in Pregnancy Study Groups criteria is associated with almost twice the risk of large-for-gestational-age babies, increased fetal adiposity, neonatal hyperinsulinemia and preeclampsia, and a 50% higher risk of preterm delivery and shoulder dystocia. The recent publication of the Hyperglycemia and Adverse Pregnancy Outcome Follow Up Study provides further evidence regarding the influence of gestational diabetes mellitus on long-term maternal and infant health. This study clearly demonstrates that hyperglycemia in pregnancy, untreated and identified post hoc by the International Association of Diabetes in Pregnancy Study Groups criteria, carries a 41.5% risk of maternal prediabetes (odds ratio, 3.72; 95% confidence interval, 3.09-4.47) and 10.7% risk of type 2 diabetes (odds ratio, 7.63; 95% confidence interval, 5.33-10.95) after 11.4 years of follow up. Gestational diabetes mellitus was also associated with higher rates of childhood overweight and obesity (prevalence 39.3% with maternal gestational diabetes mellitus; odds ratio, 1.5; 95% confidence interval, 1.56-2.44). This article places these findings in the context of other recent studies that have demonstrated that interventions that include lifestyle measures and/or metformin offer a >50% reduction in the risk of women with gestational diabetes mellitus experiencing the development of overt diabetes mellitus after their index gestational diabetes mellitus pregnancy. Although prevention of obesity and prediabetes in offspring by pregnancy treatment of gestational diabetes mellitus has not been demonstrated to date, we argue that the immediate pregnancy benefits and opportunities for long-term improvements in maternal health justify a reevaluation of the current ambivalent approach taken by the American College of Obstetricians and Gynecologists to gestational diabetes mellitus diagnosis, which currently allow for a choice of alternative criteria. The Carpenter-Coustan or National Diabetes Data Group criteria, listed as preferred criteria by American College of Obstetricians and Gynecologists, markedly limit the frequency of gestational diabetes mellitus in comparison with the International Association of Diabetes in Pregnancy Study Groups criteria and limit the opportunity for immediate and long-term follow up and treatment.We consider that new information from the Hyperglycemia and Pregnancy Outcome Follow Up Study and other recent publications on long-term maternal and offspring risk provides compelling arguments for a more comprehensive approach to the promotion of maternal and infant health through all the life cycle
Performance of an area variable MOS varicap weighted programmable CCD transversal filter
The performance of an electrically programmable CCD transversal filter (PTF) is presented in which tap-weight multiplication is performed by a novel and compact on chip voltage controlled area variable MOS varicap
Information entropy and nucleon correlations in nuclei
The information entropies in coordinate and momentum spaces and their sum
(, , ) are evaluated for many nuclei using "experimental"
densities or/and momentum distributions. The results are compared with the
harmonic oscillator model and with the short-range correlated distributions. It
is found that depends strongly on and does not depend very much
on the model. The behaviour of is opposite. The various cases we consider
can be classified according to either the quantity of the experimental data we
use or by the values of , i.e., the increase of the quality of the density
and of the momentum distributions leads to an increase of the values of . In
all cases, apart from the linear relation , the linear relation
also holds. V is the mean volume of the nucleus. If is
considered as an ensemble entropy, a relation between or and the
ensemble volume can be found. Finally, comparing different electron scattering
experiments for the same nucleus, it is found that the larger the momentum
transfer ranges, the larger the information entropy is. It is concluded that
could be used to compare different experiments for the same nucleus and to
choose the most reliable one.Comment: 14 pages, 4 figures, 2 table
Experimental and Theoretical Investigation of Droplet Evaporation on Heated Hydrophilic and Hydrophobic Surfaces
The evaporation characteristics of sessile droplets on heated hydrophobic and hydrophilic surfaces are investigated. Results are reported for the evaporation of water droplet volumes covering a range of shapes dominated by surface tension or gravity and over a range of temperatures between 40 and 60 °C. The weight evolution and total time of evaporation is measured using a novel self-contained heating stage on a high resolution analytical balance, which has advantages over visualization measurement techniques as it allows free choice of the initial droplet size and surface and the ability to record the droplet evaporation right through to the final stages of droplet life. Evaporation is modeled through a combination of a constant contact area and a constant contact angle model with the switch from the former to the latter occurring when the contact angle falls below its predetermined receding value. Theoretical results compare well with the experimental results for the hydrophobic substrate. However, a significant deviation is observed for the hydrophilic substrate due to the combined effects of the droplet surface cooling due to evaporation and buoyancy effects that are not included in the model. The proposed method of using the stick–slip model offers a convenient means of modeling droplet evaporation by mimicking the drying modes based on initial measurements of the static and receding contact angles
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