5,166 research outputs found
Sector insights: skills and performance challenges in the digital and creative sector: June 2015
Improving asthma during pregnancy with dietary antioxidants: the current evidence
The complication of asthma during pregnancy is associated with a number of poor outcomes for the mother and fetus. This may be partially driven by increased oxidative stress induced by the combination of asthma and pregnancy. Asthma is a chronic inflammatory disease of the airways associated with systemic inflammation and oxidative stress, which contributes to worsening asthma symptoms. Pregnancy alone also intensifies oxidative stress through the systemic generation of excess reactive oxidative species (ROS). Antioxidants combat the damaging effects of ROS; yet antioxidant defenses are reduced in asthma. Diet and nutrition have been postulated as potential factors to combat the damaging effects of asthma. In particular, dietary antioxidants may play a role in alleviating the heightened oxidative stress in asthma. Although there are some observational and interventional studies that have shown protective effects of antioxidants in asthma, assessment of antioxidants in pregnancy are limited and there are no antioxidant intervention studies in asthmatic pregnancies on asthma outcomes. The aims of this paper are to (i) review the relationships between oxidative stress and dietary antioxidants in adults with asthma and asthma during pregnancy, and (ii) provide the rationale for which dietary management strategies, specifically increased dietary antioxidants, might positively impact maternal asthma outcomes. Improving asthma control through a holistic antioxidant dietary approach might be valuable in reducing asthma exacerbations and improving asthma management during pregnancy, subsequently impacting perinatal health.Jessica A. Grieger, Lisa G. Wood and Vicki L. Clifto
Birefringence of interferential mirrors at normal incidence Experimental and computational study
In this paper we present a review of the existing data on interferential
mirror birefringence. We also report new measurements of two sets of mirrors
that confirm that mirror phase retardation per reflection decreases when mirror
reflectivity increases. We finally developed a computational code to calculate
the expected phase retardation per reflection as a function of the total number
of layers constituting the mirror. Different cases have been studied and we
have compared computational results with the trend of the experimental data.
Our study indicates that the origin of the mirror intrinsic birefringence can
be ascribed to the reflecting layers close to the substrate.Comment: To be published in Applied Physics
Dynamics of Bid-ask Spread Return and Volatility of the Chinese Stock Market
Bid-ask spread is taken as an important measure of the financial market
liquidity. In this article, we study the dynamics of the spread return and the
spread volatility of four liquid stocks in the Chinese stock market, including
the memory effect and the multifractal nature. By investigating the
autocorrelation function and the Detrended Fluctuation Analysis (DFA), we find
that the spread return is lack of long-range memory, while the spread
volatility is long-range time correlated. Moreover, by applying the
Multifractal Detrended Fluctuation Analysis (MF-DFA), the spread return is
observed to possess a strong multifractality, which is similar to the dynamics
of a variety of financial quantities. Differently from the spread return, the
spread volatility exhibits a weak multifractal nature
Hand Preference Develops Across Childhood and Adolescence in Extremely Preterm Children: The EPICure Study.
AIM: To determine how handedness changes with age and its relation to brain injury and cognition following birth before 26 weeks of gestation. METHODS: We used data from the EPICure study of health and development following birth in the British Isles in 1995. Handedness was determined by direct observation during standardized testing at age 2.5, six, and 11 years and by self-report using the Edinburgh Handedness Inventory at 19 years. Control data from term births were included at six, 11, and 19 years. RESULTS: In extremely preterm children left handedness increased from 9% to 27% between 2.5 and 19 years, with a progressive reduction in mixed handedness from 59% to 13%. Although individual handedness scores varied over childhood, the between-group effects were consistent through 19 years, with greatest differences in females. In extremely preterm participants, neonatal brain injury was associated with lower right handedness scores at each age and left-handed participants had lower cognitive scores at 19 years after controlling for confounders, but not at other ages. CONCLUSION: Increasing hand lateralization is seen over childhood in extremely preterm survivors, but consistently more have non-right preferences at each age than controls
Fatigue evaluation in maintenance and assembly operations by digital human simulation
Virtual human techniques have been used a lot in industrial design in order
to consider human factors and ergonomics as early as possible. The physical
status (the physical capacity of virtual human) has been mostly treated as
invariable in the current available human simulation tools, while indeed the
physical capacity varies along time in an operation and the change of the
physical capacity depends on the history of the work as well. Virtual Human
Status is proposed in this paper in order to assess the difficulty of manual
handling operations, especially from the physical perspective. The decrease of
the physical capacity before and after an operation is used as an index to
indicate the work difficulty. The reduction of physical strength is simulated
in a theoretical approach on the basis of a fatigue model in which fatigue
resistances of different muscle groups were regressed from 24 existing maximum
endurance time (MET) models. A framework based on digital human modeling
technique is established to realize the comparison of physical status. An
assembly case in airplane assembly is simulated and analyzed under the
framework. The endurance time and the decrease of the joint moment strengths
are simulated. The experimental result in simulated operations under laboratory
conditions confirms the feasibility of the theoretical approach
Theory of Star Formation
We review current understanding of star formation, outlining an overall
theoretical framework and the observations that motivate it. A conception of
star formation has emerged in which turbulence plays a dual role, both creating
overdensities to initiate gravitational contraction or collapse, and countering
the effects of gravity in these overdense regions. The key dynamical processes
involved in star formation -- turbulence, magnetic fields, and self-gravity --
are highly nonlinear and multidimensional. Physical arguments are used to
identify and explain the features and scalings involved in star formation, and
results from numerical simulations are used to quantify these effects. We
divide star formation into large-scale and small-scale regimes and review each
in turn. Large scales range from galaxies to giant molecular clouds (GMCs) and
their substructures. Important problems include how GMCs form and evolve, what
determines the star formation rate (SFR), and what determines the initial mass
function (IMF). Small scales range from dense cores to the protostellar systems
they beget. We discuss formation of both low- and high-mass stars, including
ongoing accretion. The development of winds and outflows is increasingly well
understood, as are the mechanisms governing angular momentum transport in
disks. Although outstanding questions remain, the framework is now in place to
build a comprehensive theory of star formation that will be tested by the next
generation of telescopes.Comment: 120 pages, to appear in ARAA. No changes from v1 text; permission
statement adde
Compulsory reduced working time in Belarus: Incidence, operation and consequences
This article examines compulsory reduced working time (CRWT) in five Belarusian factories, to assess its impact on employment relationships and evaluate arguments about ‘Soviet legacies’ and labour ‘patience’. Local use of CRWT increased between 2001 and 2012, and took a form more inimical to worker interests, thereby differing from official macro statistics. Managers expressed discontent at being pushed by state policy to use CRWT, but used it as a disciplinary tool. Workers perceived worsening work relationships and threats of collective response were in evidence. Arguments about ‘Soviet legacies’ and labour’s ‘patience’ therefore currently appear inappropriate
Comment on the narrow structure reported by Amaryan et al
The CLAS Collaboration provides a comment on the physics interpretation of
the results presented in a paper published by M. Amaryan et al. regarding the
possible observation of a narrow structure in the mass spectrum of a
photoproduction experiment.Comment: to be published in Physical Review
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