7,802 research outputs found
The association of maternal prenatal psychosocial stress with vascular function in the child at age 10-11 years: findings from the Avon longitudinal study of parents and children
Objective To investigate whether (1) maternal psychosocial stress (depression/anxiety) during pregnancy is associated with offspring vascular function and (2) whether any association differs depending on the gestational timing of exposure to stress. We also investigated whether any association is likely to be due to intrauterine mechanisms by (3) comparing with the association of paternal stress with offspring vascular function and (4) examining whether any prenatal association is explained by maternal postnatal stress.
Methods and results Associations were examined in a UK birth cohort, with offspring outcomes (systolic and diastolic blood pressure, SBP and DBP, endothelial function assessed by brachial artery flow-mediated dilatation (FMD); arterial stiffness assessed by carotid to radial pulse wave velocity (PWV), brachial artery distensibility (DC), and brachial artery diameter (BD) assessed at age 10–11 years (n = 4318). Maternal depressive symptoms and anxiety were assessed at 18 and 32 weeks gestation and 8 months postnatally. Paternal symptoms were assessed at week 19. With the exception of DBP and BD, there were no associations of maternal depressive symptoms with any of the vascular outcomes. Maternal depressive and anxiety symptoms were associated with lower offspring DBP and wider BD, though the latter attenuated to the null with adjustment for confounding factors. Paternal symptoms were not associated with offspring outcomes. Maternal postnatal depressive symptoms were associated with lower offspring SBP.
Conclusions We found no evidence to support the hypothesis that maternal stress during pregnancy adversely affects offspring vascular function at age 10–12 years via intrauterine mechanisms
Magnetism of Superconducting UPt3
The phase diagram of superconducting in pressure-temperature
plane, together with the neutron scattering data is studied within a two
component superconducting order parameter scenario. In order to give a
qualitative explanation to the experimental data a set of two linearly
independent antiferromagnetic moments which emerge appropriately at the
temperature \mbox{} and \mbox{} and
couple to superconductivity is proposed. Several constraints on the fourth
order coefficients in the Ginzburg-Landau free energy are obtained.Comment: 17 pages, figures available on request to
[email protected]
Free initial wave packets and the long-time behavior of the survival and nonescape probabilities
The behavior of both the survival S(t) and nonescape P(t) probabilities at
long times for the one-dimensional free particle system is shown to be closely
connected to that of the initial wave packet at small momentum. We prove that
both S(t) and P(t) asymptotically exhibit the same power-law decrease at long
times, when the initial wave packet in momentum representation behaves as O(1)
or O(k) at small momentum. On the other hand, if the integer m becomes greater
than 1, S(t) and P(t) decrease in different power-laws at long times.Comment: 4 pages, 3 figures, Title and organization changed, however the
results not changed, To appear in Phys. Rev.
Macroeconomic Crisis and Individual Firm Performance: The Mexican Experience
This paper considers financial, operational, solvency, and performance ratios, in order to detect when there were balance sheets’ variations related to the 1994 Mexican currency crisis. Quarterly results for 88 non-financial Mexican companies that survived the crisis are used, and tests for structural change are performed. Findings show that generally firms’ balance sheets deteriorated between the fourth quarters of 1993 and 1995, which points the possibility of corporate roots of the macroeconomic crisis. Although in most cases firms’ balance sheets improved after the crisis, the recovery was partial and gradual, and overall this episode was prejudicial even for surviving companies
The social cognition of medical knowledge, with special reference to childhood epilepsy
This paper arose out of an engagement in medical communication courses at a Gulf university. It deploys a theoretical framework derived from a (critical) sociocognitive approach to discourse analysis in order to investigate three aspects of medical discourse relating to childhood epilepsy: the cognitive processes that are entailed in relating different types of medical knowledge to their communicative context; the types of medical knowledge that are constituted in the three different text types analysed; and the relationship between these different types of medical knowledge and the discursive features of each text type. The paper argues that there is a cognitive dimension to the human experience of understanding and talking about one specialized from of medical knowledge. It recommends that texts be studied in medical communication courses not just in terms of their discrete formal features but also critically, in terms of the knowledge which they produce, transmit and reproduce
Economic Development and Infrastructure: The Case of Balochistan Province
In designing a future road network, public budget constraints
force administrations to make choices. The objective of economic
development requires that both efficiency and equity are taken into
account. The present analysis operationalises these two concepts by
social and economic accessibility in Balochistan. It suggests priorities
which can serve as an input for the design of the future road
network
Liposomal Antioxidants for Protection against Oxidant-Induced Damage
Reactive oxygen species (ROS), including superoxide anion, hydrogen peroxide, and hydroxyl radical, can be formed as normal products of aerobic metabolism and can be produced at elevated rates under pathophysiological conditions. Overproduction and/or insufficient removal of ROS result in significant damage to cell structure and functions. In vitro studies showed that antioxidants, when applied directly and at relatively high concentrations to cellular systems, are effective in conferring protection against the damaging actions of ROS, but results from animal and human studies showed that several antioxidants provide only modest benefit and even possible harm. Antioxidants have yet to be rendered into reliable and safe therapies because of their poor solubility, inability to cross membrane barriers, extensive first-pass metabolism, and rapid clearance from cells. There is considerable interest towards the development of drug-delivery systems that would result in the selective delivery of antioxidants to tissues in sufficient concentrations to ameliorate oxidant-induced tissue injuries. Liposomes are biocompatible, biodegradable, and nontoxic artificial phospholipid vesicles that offer the possibility of carrying hydrophilic, hydrophobic, and amphiphilic molecules. This paper focus on the use of liposomes for the delivery of antioxidants in the prevention or treatment of pathological conditions related to oxidative stress
Empirical comparison of discrete choice experiment and best-worst scaling to estimate stakeholders' risk tolerance for hip replacement surgery
Objectives Empirical comparison of two preference elicitation methods, discrete choice experiment (DCE) and profile case best-worst scaling (BWS), regarding the estimation of the risk tolerance for hip replacement surgery (total hip arthroplasty and total hip resurfacing arthroplasty). Methods An online survey was constructed, following international guidelines, and consisted of socio-demographic questions and two randomised sections with 12 DCE and 8 BWS questions. The survey was sent to a general population who can be faced with choosing between THA and TRA (males between 45-65 years old) in the US. After an intensive literature search, the following attributes were selected: probability of a first and a second revision in seven years, pain relief, ability to perform moderate daily activities, and hospital stay. In addition, survey respondents rated the difficulty of each method and the time to complete each section was monitored. BWS and DCE data was analysed using conditional logit analysis. The maximum acceptable risk (MAR) for a revision was estimated for four different hypothetical hip replacement scenarios. Results The final data set consisted of 429 respondents. The MARs estimated for four hypothetical hip replacement scenarios differed between both methods, ranging from 0% to 19% difference for a first revision. BWS questions took significantly more time (401 s.) than DCE (228 s.) questions. And respondents found BWS more difficult to complete. Conclusions Both methods to elicit stakeholder preferences produce different results. Yet, both seem to be consistent in predicting risk tolerance if the benefits are changed. However, DCE seems to be more sensitive for a change in benefits and risks while the MAR estimates obtained through BWS have considerably lower uncertainty than DC
Daily Exchange Rate Behaviour and Hedging of Currency Risk
Exchange rates typically exhibit time-varying patterns in both means and variances. The histograms of such series indicate heavy tails. In this paper we construct models which enable a decision-maker to analyze the implications of such time series patterns for currency risk management. Our approach is Bayesian where extensive use is made of Markov chain Monte Carlo methods. The effects of several model characteristics (unit roots, GARCH, stochastic volatility, heavy tailed disturbance densities) are investigated in relation to the hedging decision strategies. Consequently, we can make a distinction between statistical relevance of model specifications, and the economic consequences from a risk management point of view. The empirical results suggest that econometric modelling of heavy tails and time-varying means and variances pays off compared to a efficient markets model. The different ways to measure persistence and changing volatilities appear to strongly influence the hedging decision the investor faces.
Semiclassical corrections to the interaction energy of a hard-sphere Boltzmann gas
Quantum effects in statistical mechanics are important when the thermal
wavelength is of the order of, or greater than, the mean interatomic spacing.
This is examined at depth taking the example of a hard-sphere Boltzmann gas.
Using the virial expansion for the equation of state, it is shown that the
interaction energy of a classical hard-sphere gas is exactly zero. When the
(second) virial coefficient of such a gas is obtained quantum mechanically,
however, the quantum contribution to the interaction energy is shown to be
substantial. The importance of the semiclassical corrections to the interaction
energy shows up dramatically in such a system.Comment: 9 pages, 3 figures, submitted to Eur. J. Phy
- …