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The APOE ε4 allele is associated with a reduction in FEV1/FVC in women: A cross-sectional analysis of the Long Life Family Study
Introduction
Murine studies have shown that apolipoprotein E modulates pulmonary function during development, aging, and allergen-induced airway disease. It is not known whether the polymorphic human APOE gene influences pulmonary function.
Objectives
We assessed whether an association exists between the polymorphic human APOE ε2, ε3, and ε4 alleles and pulmonary function among participants in the Long Life Family Study.
Methods
Data from 4,468 Caucasian subjects who had genotyping performed for the APOE ε2, ε3, and ε4 alleles were analyzed, with and without stratification by sex. Statistical models were fitted considering the effects of the ε2 allele, defined as ε2/2 or ε2/3 genotypes, and the ε4 allele, defined as ε3/4 or ε4/4 genotypes, which were compared to the ε3/3 genotype.
Results
The mean FEV1/FVC ratio (the forced expiratory volume in one second divided by the forced vital capacity) was lower among women with the ε4 allele as compared to women with the ε3/3 genotype or the ε2 allele. Carriage of the APOE ε4 allele was associated with FEV1/FVC, which implied lower values. Further analysis showed that the association primarily reflected women without lung disease who were older than 70 years. The association was not mediated by lipid levels, smoking status, body mass index, or cardiovascular disease.
Conclusions
This study for the first time identifies that the APOE gene is associated with modified lung physiology in women. This suggests that a link may exist between the APOE ε4 allele, female sex, and a reduction in the FEV1/FVC ratio in older individuals
Black Hole Spectroscopy: Testing General Relativity through Gravitational Wave Observations
Assuming that general relativity is the correct theory of gravity in the
strong field limit, can gravitational wave observations distinguish between
black hole and other compact object sources? Alternatively, can gravitational
wave observations provide a test of one of the fundamental predictions of
general relativity? Here we describe a definitive test of the hypothesis that
observations of damped, sinusoidal gravitational waves originated from a black
hole or, alternatively, that nature respects the general relativistic no-hair
theorem. For astrophysical black holes, which have a negligible charge-to-mass
ratio, the black hole quasi-normal mode spectrum is characterized entirely by
the black hole mass and angular momentum and is unique to black holes. In a
different theory of gravity, or if the observed radiation arises from a
different source (e.g., a neutron star, strange matter or boson star), the
spectrum will be inconsistent with that predicted for general relativistic
black holes. We give a statistical characterization of the consistency between
the noisy observation and the theoretical predictions of general relativity,
together with a numerical example.Comment: 19 pages, 7 figure
The Evolving Landscape of the Economics of HIV Treatment and Prevention
Bohdan Nosyk and Julio Montaner argue that the cost-effectiveness of HAART roll out has been significantly underestimated because economic analyses haven't yet taken into account the beneficial impact of HAART on HIV transmission
Validation of World Health Organisation HIV/AIDS Clinical Staging in Predicting Initiation of Antiretroviral Therapy and Clinical Predictors of Low CD4 Cell Count in Uganda
IntroductionThe WHO clinical guidelines for HIV/AIDS are widely used in resource limited settings to represent the gold standard of CD4 counts for antiviral therapy initiation. The utility of the WHO-defined stage 1 and 2 clinical factors used in WHO HIV/AIDS clinical staging in predicting low CD4 cell count has not been established in Uganda. Although the WHO staging has shown low sensitivity for predicting CD4<200 cells/mm(3), it has not been evaluated at for CD4 cut-offs of <250 cells/mm(3) or <350 cells/mm(3).ObjectiveTo validate the World Health Organisation HIV/AIDS clinical staging in predicting initiation of antiretroviral therapy in a low-resource setting and to determine the clinical predictors of low CD4 cell count in Uganda.ResultsData was collected on 395 participants from the Joint Clinical Research Centre, of whom 242 (61.3%) were classified as in stages 1 and 2 and 262 (68%) were females. Participants had a mean age of 36.8 years (SD 8.5). We found a significant inverse correlation between the CD4 lymphocyte count and WHO clinical stages. The sensitivity the WHO clinical staging at CD4 cell count of 250 cells/mm(3) and 350 cells/mm(3) was 53.5% and 49.1% respectively. Angular cheilitis, papular pruritic eruptions and recurrent upper respiratory tract infections were found to be significant predictors of low CD4 cell count among participants in WHO stage 1 and 2.ConclusionThe WHO HIV/AIDS clinical staging guidelines have a low sensitivity and about half of the participants in stages 1 and 2 would be eligible for ART initiation if they had been tested for CD4 count. Angular cheilitis and papular pruritic eruptions and recurrent upper respiratory tract infections may be used, in addition to the WHO staging, to improve sensitivity in the interim, as access to CD4 machines increases in Uganda
Effect of Electron Energy Distribution Function on Power Deposition and Plasma Density in an Inductively Coupled Discharge at Very Low Pressures
A self-consistent 1-D model was developed to study the effect of the electron
energy distribution function (EEDF) on power deposition and plasma density
profiles in a planar inductively coupled plasma (ICP) in the non-local regime
(pressure < 10 mTorr). The model consisted of three modules: (1) an electron
energy distribution function (EEDF) module to compute the non-Maxwellian EEDF,
(2) a non-local electron kinetics module to predict the non-local electron
conductivity, RF current, electric field and power deposition profiles in the
non-uniform plasma, and (3) a heavy species transport module to solve for the
ion density and velocity profiles as well as the metastable density. Results
using the non-Maxwellian EEDF model were compared with predictions using a
Maxwellian EEDF, under otherwise identical conditions. The RF electric field,
current, and power deposition profiles were different, especially at 1mTorr,
for which the electron effective mean free path was larger than the skin depth.
The plasma density predicted by the Maxwellian EEDF was up to 93% larger for
the conditions examined. Thus, the non-Maxwellian EEDF must be accounted for in
modeling ICPs at very low pressures.Comment: 19 pages submitted to Plasma Sources Sci. Techno
Antiretroviral (ARV) Therapy in Resource Poor Countries: What do we Need in Real Life?
Significant progresses have been made in the last 5 years towards the ultimate goal to provide universal access to care for all HIV/AIDS patients needing antiretroviral treatment in resource-poor countries. However, many barriers are still to be overcome, including (●) cost of care for the individual, (●) stigma, (●) lack of qualified human resources and infrastructure, especially in the rural setting, (●) rescue drugs for failing patients and (●) pediatric formulations. Priority actions to be promoted if the fight against HIV/AIDS is to be successful include: (i) promoting access to care in the rural areas, (ii) strengthening of basic health infrastructures, (iii) waiving of users’ fee to get ARV, (iv) a larger variety of drugs, with particular regard to fixed dose combination third line drugs and pediatric formulations, (v) local quality training and (vi) high quality basic and translational research. While the universal access to HIV care is crucial in developing countries, a strong emphasis on prevention should be maintained along
Quantum state preparation and macroscopic entanglement in gravitational-wave detectors
Long-baseline laser-interferometer gravitational-wave detectors are operating
at a factor of 10 (in amplitude) above the standard quantum limit (SQL) within
a broad frequency band. Such a low classical noise budget has already allowed
the creation of a controlled 2.7 kg macroscopic oscillator with an effective
eigenfrequency of 150 Hz and an occupation number of 200. This result, along
with the prospect for further improvements, heralds the new possibility of
experimentally probing macroscopic quantum mechanics (MQM) - quantum mechanical
behavior of objects in the realm of everyday experience - using
gravitational-wave detectors. In this paper, we provide the mathematical
foundation for the first step of a MQM experiment: the preparation of a
macroscopic test mass into a nearly minimum-Heisenberg-limited Gaussian quantum
state, which is possible if the interferometer's classical noise beats the SQL
in a broad frequency band. Our formalism, based on Wiener filtering, allows a
straightforward conversion from the classical noise budget of a laser
interferometer, in terms of noise spectra, into the strategy for quantum state
preparation, and the quality of the prepared state. Using this formalism, we
consider how Gaussian entanglement can be built among two macroscopic test
masses, and the performance of the planned Advanced LIGO interferometers in
quantum-state preparation
Estimating the Resources Needed and Savings Anticipated from Roll-Out of Adult Male Circumcision in Sub-Saharan Africa
Background: Trials in Africa indicate that medical adult male circumcision (MAMC) reduces the risk of HIV by 60%. MAMC may avert 2 to 8 million HIV infections over 20 years in sub-Saharan Africa and cost less than treating those who would have been infected. This paper estimates the financial and human resources required to roll out MAMC and the net savings due to reduced infections. Methods: We developed a model which included costing, demography and HIV epidemiology. We used it to investigate 14 countries in sub-Saharan Africa where the prevalence of male circumcision was lower than 80% and HIV prevalence among adults was higher than 5%, in addition to Uganda and the Nyanza province in Kenya. We assumed that the roll-out would take 5 years and lead to an MC prevalence among adult males of 85%. We also assumed that surgery would be done as it was in the trials. We calculated public program cost, number of full-time circumcisers and net costs or savings when adjusting for averted HIV treatments. Costs were in USD, discounted to 2007. 95% percentile intervals (95% PI) were estimated by Monte Carlo simulations. Results: In the first 5 years the number of circumcisers needed was 2 282 (95% PI: 2 018 to 2 959), or 0.24 (95% PI: 0.21 to 0.31) per 10 000 adults. In years 6-10, the number of circumcisers needed fell to 513 (95% PI: 452 to 664). The estimated 5-year cost of rolling out MAMC in the public sector was 672 million (95% PI: 437 to 1 021) and over 20 years there were net savings of $2.3 billion (95% PI: 1.4 to 3.4). Conclusion: A rapid roll-out of MAMC in sub-Saharan Africa requires substantial funding and a high number of circumcisers for the first five years. These investments are justified by MAMC's substantial health benefits and the savings accrued by averting future HIV infections. Lower ongoing costs and continued care savings suggest long-term sustainability
Sailing into a dilemma : an economic and legal analysis of an EU trading scheme for maritime emissions
On the basis of a joint economic and legal analysis, we evaluate the effects of a “regional” (European)
emission trading scheme aiming at reducing emissions of international shipping. The focus lies on the
question which share of emissions from maritime transport activities to and from the EU can and
should be included in such a system. Our findings suggest that the attempt to implement an EU
maritime ETS runs into a dilemma. It is not possible to design a system that achieves emission
reductions in a cost efficient manner and is compatible with international law
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