4,645 research outputs found
Factors affecting continued use of ceramic water purifiers distributed to Tsunami-affected Communities in Sri Lanka
Objectives  There is little information about continued use of point-of-use technologies after disaster relief efforts. After the 2004 tsunami, the Red Cross distributed ceramic water filters in Sri Lanka. This study determined factors associated with filter disuse and evaluate the quality of household drinking water. Methods  A cross-sectional survey of water sources and treatment, filter use and household characteristics was administered by in-person oral interview, and household water quality was tested. Multivariable logistic regression was used to model probability of filter non-use. Results  At the time of survey, 24% of households (107/452) did not use filters; the most common reason given was breakage (42%). The most common household water sources were taps and wells. Wells were used by 45% of filter users and 28% of non-users. Of households with taps, 75% had source water Escherichia coli in the lowest World Health Organisation risk category (<1/100 ml), vs. only 30% of households reporting wells did. Tap households were approximately four times more likely to discontinue filter use than well households. Conclusion  After 2 years, 24% of households were non-users. The main factors were breakage and household water source; households with taps were more likely to stop use than households with wells. Tap water users also had higher-quality source water, suggesting that disuse is not necessarily negative and monitoring of water quality can aid decision-making about continued use. To promote continued use, disaster recovery filter distribution efforts must be joined with capacity building for long-term water monitoring, supply chains and local production
The Off-forward Quark-Quark Correlation Function
The properties of the non-forward quark-quark correlation function are
examined. We derive constraints on the correlation function from the
transformation properties of the fundamental fields of QCD occurring in its
definition. We further develop a method to construct an ansatz for this
correlator. We present the complete leading order set of generalized parton
distributions in terms of the amplitudes of the ansatz. Finally we conclude
that the number of independent generalized parton helicity changing
distributions is four.Comment: Accepted for publication in Physical Review
Hydrogen charging of carbon and low alloy steel by electrochemical methods
Atomic hydrogen can be the result of different processes like electroplating, chemical and electrochemical pickling treatments, in welding or by cathodic processes in corrosive fluids. Moreover, adsorption of atomic hydrogen can affect materials in contact with high pressure gaseous hydrogen. Once entered the material, atomic hydrogen interacts with the metal structure and may produce a "damage" of various forms, such as Hydrogen Induced Cracking (HIC), delayed fracture, blistering and hydrogen embrittlement. In particular, when H2S is present ("sour service"), metallic materials, such as carbon and low alloy steels, may suffer hydrogen damage and hydrogen embrittlement. Sour service materials must be used in compliance with international accepted standards, used worldwide in oil and gas activities, when fluids are classified as sour. The present study has been carried out in order to set up an electrochemical method to charge with hydrogen two typical pipeline materials, carbon and low alloy steels. The reason of the use of an electrochemical method is to avoid any critical conditions from the point of view of preparation, safety and disposal. Hydrogen content in the specimens was measured by two different methods: hot glycerol bath and Inert Gas Fusion (IGF) analysis. Hydrogen content in the specimens is about 0.6-2 ppm; mechanical performances were assessed by means of J integral tests: a pronounced decrease of fracture toughness was observed for H charged specimens.{GRAPHIACAL ABSTRACT
Immune, Autonomic, and Endocrine Dysregulation in Autism and Ehlers-Danlos Syndrome/Hypermobility Spectrum Disorders Versus Unaffected Controls
Background: A growing body of literature suggests etiological overlap between Ehlers-Danlos syndrome (EDS)/hypermobility spectrum disorders (HSD) and some cases of autism, although this relationship is poorly delineated. In addition, immune, autonomic, and endocrine dysregulation are reported in both conditions and may be relevant to their respective etiologies.
Aims: To study symptom overlap in these two comorbid spectrum conditions.
Methods and Procedures: We surveyed 702 adults aged 25+ years on a variety of EDS/HSD-related health topics, comparing individuals with EDS/HSD, autism, and unaffected controls.
Outcomes and Results: The autism group reported similar though less severe symptomology as the EDS/HSD group, especially in areas of immune/autonomic/endocrine dysregulation, connective tissue abnormalities (i.e., skin, bruising/bleeding), and chronic pain. EDS/HSD mothers with autistic children reported more immune symptoms than EDS/HSD mothers without, suggesting the maternal immune system could play a heritable role in these conditions (p = 0.0119).
Conclusions and Implications: These data suggest that EDS/HSD and autism share aspects of immune/autonomic/endocrine dysregulation, pain, and some tissue fragility, which is typically more severe in the former. This overlap, as well as documented comorbidity, suggests some forms of autism may be hereditary connective tissue disorders (HCTD)
Quantum Simulation of Quantum Field Theories in Trapped Ions
We propose the quantum simulation of a fermion and an antifermion field modes
interacting via a bosonic field mode, and present a possible implementation
with two trapped ions. This quantum platform allows for the scalable add-up of
bosonic and fermionic modes, and represents an avenue towards quantum
simulations of quantum field theories in perturbative and nonperturbative
regimes.Comment: To be published in Physical Review Letter
In-situ characterisation of the corrosion products formed on C-steel immersed in a soil-simulating solution
A systematic comparison of supervised classifiers
Pattern recognition techniques have been employed in a myriad of industrial,
medical, commercial and academic applications. To tackle such a diversity of
data, many techniques have been devised. However, despite the long tradition of
pattern recognition research, there is no technique that yields the best
classification in all scenarios. Therefore, the consideration of as many as
possible techniques presents itself as an fundamental practice in applications
aiming at high accuracy. Typical works comparing methods either emphasize the
performance of a given algorithm in validation tests or systematically compare
various algorithms, assuming that the practical use of these methods is done by
experts. In many occasions, however, researchers have to deal with their
practical classification tasks without an in-depth knowledge about the
underlying mechanisms behind parameters. Actually, the adequate choice of
classifiers and parameters alike in such practical circumstances constitutes a
long-standing problem and is the subject of the current paper. We carried out a
study on the performance of nine well-known classifiers implemented by the Weka
framework and compared the dependence of the accuracy with their configuration
parameter configurations. The analysis of performance with default parameters
revealed that the k-nearest neighbors method exceeds by a large margin the
other methods when high dimensional datasets are considered. When other
configuration of parameters were allowed, we found that it is possible to
improve the quality of SVM in more than 20% even if parameters are set
randomly. Taken together, the investigation conducted in this paper suggests
that, apart from the SVM implementation, Weka's default configuration of
parameters provides an performance close the one achieved with the optimal
configuration
Quantum Simulation of Interacting Fermion Lattice Models in Trapped Ions
We propose a method of simulating efficiently many-body interacting fermion
lattice models in trapped ions, including highly nonlinear interactions in
arbitrary spatial dimensions and for arbitrarily distant couplings. We map
products of fermionic operators onto nonlocal spin operators and decompose the
resulting dynamics in efficient steps with Trotter methods, yielding an overall
protocol that employs only polynomial resources. The proposed scheme can be
relevant in a variety of fields as condensed-matter or high-energy physics,
where quantum simulations may solve problems intractable for classical
computers.Comment: 5 pages, 2 figures + Supplementary Materia
Sex and Gender in Medical Education, and proceedings from the 2015 Sex and Gender Education Summit
The Sex and Gender Medical Education Summit: a roadmap for curricular innovation was a collaborative initiative of the American Medical Women\u27s Association, Laura W. Bush Institute for Women’s Health, Mayo Clinic, and Society for Women\u27s Health Research (www.sgbmeducationsummit.com). It was held on October 18–19, 2015 to provide a unique venue for collaboration among nationally and internationally renowned experts in developing a roadmap for the incorporation of sex and gender based concepts into medical education curricula. The Summit engaged 148 in-person attendees for the 1 1/2-day program. Pre- and post-Summit surveys assessed the impact of the Summit, and workshop discussions provided a framework for informal consensus building. Sixty-one percent of attendees indicated that the Summit had increased their awareness of the importance of sex and gender specific medicine. Other comments indicate that the Summit had a significant impact for motivating a call to action among attendees and provided resources to initiate change in curricula within their home institutions. These educational efforts will help to ensure a sex and gender basis for delivery of health care in the future
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