5,941 research outputs found
LIPN: Introducing a new Geographical Context Similarity Measure and a Statistical Similarity Measure based on the Bhattacharyya coefficient
International audienceThis paper describes the system used by the LIPN team in the task 10, Multilingual Semantic Textual Similarity, at SemEval 2014, in both the English and Spanish sub-tasks. The system uses a support vector regression model, combining different text similarity measures as features. With respect to our 2013 participation, we included a new feature to take into account the geographical context and a new semantic distance based on the Bhattacharyya distance calculated on co-occurrence distributions derived from the Spanish Google Books n-grams dataset
Validity of a self-reported diagnosis of depression among participants in a cohort study using the Structured Clinical Interview for DSM-IV (SCID-I).
Abstract
Background: Depression assessment in population studies is usually based on depressive
symptoms scales. However, the use of scales could lead to the choice of an arbitrary cut-off
point depending on the sample characteristics and on the patient diagnosis. Thus, the use of a
medical diagnosis of depression could be a more appropriate approach.
Objective: To validate a self-reported physician diagnosis of depression using the Structured
Clinical Interview for DSM-IV (SCID-I) as Gold Standard and to assess the factors associated to
a valid self-reported diagnosis.
Methods: The SUN Project is a cohort study based on university graduates followed-up through
postal questionnaires. The response to the question included in the questionnaire: Have you
ever been diagnosed of depression by a physician? was compared to that obtained through the
SCID-I applied by a psychiatrist or a clinical psychologist. The percentages of confirmed
depression and non-depression were assessed for the overall sample and according to several
characteristics. Logistic regression models were fitted to ascertain the association between
different factors and a correct classification regarding depression status.
Results: The percentage of confirmed depression was 74.2%; 95% confidence interval (95%
CI) =63.3-85.1. Out of 42 participants who did not report a depression diagnosis in the
questionnaire, 34 were free of the disease (%confirmed non-depression=81.1%; 95% CI=69.1-
92.9). The probability of being a true positive was higher among ex- smokers and non-smokers
and among those overweight or obese but the differences were not statistically significant.
Conclusion: The validity of a self-reported diagnosis of depression in the SUN cohort is
adequate. Thus, this question about depression diagnosis could be used in further
investigations regarding this disease in this graduate cohort study
Anticipated Notification of Sexual Partners following STD Diagnosis among Men Who Have Sex with Men and Transgender Women in Lima, Peru: A Mixed Methods Analysis
Background: New strategies to support partner notification (PN) are critical for STD control and require detailed understanding of how specific individual and partnership characteristics guide notification decisions.
Methods: From 2011 to 2012, 397 MSM and TW recently diagnosed with HIV, syphilis, or another STD completed a survey on anticipated notification of recent sexual partners and associated factors. Qualitative interviews were conducted with a subset of participants to provide further depth to quantitative findings. Prevalence ratios and generalized estimating equation (GEE) models were used to analyze participant- and partner-level factors associated with anticipated PN.
Results: Among all partners reported, 52.5% were described as “Very Likely” or “Somewhat Likely” to be notified. Anticipated notification was more likely for main partners than casual (adjusted Prevalence Ratio [aPR], 95% CI: 0.63, 0.54–0.75) or commercial (aPR, 95% CI: 0.44, 0.31–0.62) partners. Other factors associated with likely notification included perception of the partner as an STD source (aPR, 95% CI: 1.27, 1.10–1.48) and anticipated future sexual contact with the partner (aPR, 95% CI: 1.30, 1.11–1.52). An HIV diagnosis was associated with a lower likelihood of notification than non-HIV STDs (aPR: 0.68, 0.55–0.86). Qualitative discussion of the barriers and incentives to PN reflected a similar differentiation of anticipated notification according to partnership type and type of HIV/STD diagnosis.
Discussion: Detailed attention to how partnership characteristics guide notification outcomes is essential to the development of new PN strategies. By accurately and thoroughly assessing the diversity of partnership interactions among individuals with HIV/STD, new notification techniques can be tailored to partner-specific circumstances
Iridium-(K2-NSi) catalyzed dehydrogenation of formic acid: effect of auxiliary ligands on the catalytic performance
IThe iridium(III) complexes [Ir(H)(Cl)(κ2-NSitBu2)(κ2-bipyMe2)] (2) and [Ir(H)(OTf)(κ2-NSitBu2)(κ2-bipyMe2)] (3) (NSitBu2 = {4-methylpyridine-2-yloxy}ditertbutylsilyl) have been synthesized and characterized including X-ray studies of 3. A comparative study of the catalytic activity of complexes 2, 3, [Ir(H)(OTf)(κ2-NSitBu2)(coe)] (4), and [Ir(H)(OTf)(κ2-NSitBu2)(PCy3)] (5) (0.1 mol%) as catalysts precursors for the solventless formic acid dehydrogenation (FADH) in the presence of Et3N (40 mol%) at 353 K has been performed. The highest activity (TOF5 min ≈ 3260 h−1) has been obtained with 3 at 373 K. However, at that temperature the FTIR spectra show traces of CO together with the desired products (H2 and CO2). Thus, the best performance was achieved at 353 K (TOF5 min ≈ 1210 h−1 and no observable CO). Kinetic studies at variable temperature show that the activation energy of the 3-catalyzed FADH process is 16.76 kcal mol−1. Kinetic isotopic effect (5 min) values of 1.6, 4.5, and 4.2 were obtained for the 3-catalyzed dehydrogenation of HCOOD, DCOOH, and DCOOD, respectively, at 353 K. The strong KIE found for DCOOH and DCOOD evidenced that the hydride transfer from the C–H bond of formic acid to the metal is the rate-determining step of the process
Stellar Population gradients in galaxy discs from the CALIFA survey
While studies of gas-phase metallicity gradients in disc galaxies are common,
very little has been done in the acquisition of stellar abundance gradients in
the same regions. We present here a comparative study of the stellar
metallicity and age distributions in a sample of 62 nearly face-on, spiral
galaxies with and without bars, using data from the CALIFA survey. We measure
the slopes of the gradients and study their relation with other properties of
the galaxies. We find that the mean stellar age and metallicity gradients in
the disc are shallow and negative. Furthermore, when normalized to the
effective radius of the disc, the slope of the stellar population gradients
does not correlate with the mass or with the morphological type of the
galaxies. Contrary to this, the values of both age and metallicity at 2.5
scale-lengths correlate with the central velocity dispersion in a similar
manner to the central values of the bulges, although bulges show, on average,
older ages and higher metallicities than the discs. One of the goals of the
present paper is to test the theoretical prediction that non-linear coupling
between the bar and the spiral arms is an efficient mechanism for producing
radial migrations across significant distances within discs. The process of
radial migration should flatten the stellar metallicity gradient with time and,
therefore, we would expect flatter stellar metallicity gradients in barred
galaxies. However, we do not find any difference in the metallicity or age
gradients in galaxies with without bars. We discuss possible scenarios that can
lead to this absence of difference.Comment: 24 pages, 17 figures, accepted for publication in A&
Liver transplantation in cirrhotic patients with diabetes mellitus: Midterm results, survival, and adverse events
Liver cirrhosis is frequently associated with diabetes mellitus (DM), and this
metabolic complication is also frequent after orthotopic liver transplantation
(OLT). The aim of our study is to investigate which factors are associated with
DM before and after OLT and their impact on post-OLT evolution. We evaluated the
prevalence of DM among 115 liver transplant candidates with cirrhosis and
assessed their evolution after OLT (median follow-up, 41 months). Sixteen
candidates had DM requiring pharmacological therapy (group A), 45 candidates had
DM controlled with diet (group B), and 54 candidates did not have DM (group C).
One-year and 3-year actuarial survival rates were 100% and 100% for group A, 91%
and 85% for group B, and 77% and 74% for group C, respectively (P <.03). Post-OLT
DM was more frequent in group A. The incidence of other metabolic complications,
major infections, rejection, and arterial hypertension; the need for
hospitalization; and renal and graft function of patients in groups A, B, and C
were similar. The only risk factor for DM 1 year after OLT on multivariate
analysis was pre-OLT DM requiring pharmacological treatment. The incidence of
complications, need for hospitalization, and renal and graft function 1 year
after OLT for patients with post-OLT DM were similar to those of patients without
post-OLT DM. In conclusion, patients with cirrhosis who have DM have a greater
risk for post-OLT DM, but their midterm survival is not worse than the survival
of those without DM
Paper-based ZnO self-powered sensors and nanogenerators by plasma technology
Nanogenerators and self-powered nanosensors have shown the potential to power
low-consumption electronics and human-machine interfaces, but their practical
implementation requires reliable, environmentally friendly and scalable,
processes for manufacturing and processing. This article presents a plasma
synthesis approach for the fabrication of piezoelectric nanogenerators (PENGs)
and self-powered sensors on paper substrates. Polycrystalline ZnO nanocolumnar
thin films are deposited by plasma-enhanced chemical vapour deposition on
common paper supports using a microwave electron cyclotron resonance reactor
working at room temperature yielding high growth rates and low structural and
interfacial stresses. Applying Kinetic Monte Carlo simulation, we elucidate the
basic shadowing mechanism behind the characteristic microstructure and porosity
of the ZnO thin films, relating them to an enhanced piezoelectric response to
periodic and random inputs. The piezoelectric devices are assembled by
embedding the ZnO films in PMMA and using Au electrodes in two different
configurations: laterally and vertically contacted devices. We present the
response of the laterally connected devices as a force sensor for low-frequency
events with different answers to the applied force depending on the impedance
circuit, i.e. load values range, a behaviour that is theoretically analyzed.
The vertical devices reach power densities as high as 80 nW/cm2 with a mean
power output of 20 nW/cm2. We analyze their actual-scenario performance by
activation with a fan and handwriting. Overall, this work demonstrates the
advantages of implementing plasma deposition for piezoelectric films to develop
robust, flexible, stretchable, and enhanced-performance nanogenerators and
self-powered piezoelectric sensors compatible with inexpensive and recyclable
supportsComment: 30 pages, 8 figures in main tex
MIGRATE: mobile device virtualisation through state transfer
Delegation of processing tasks to the network has moved from cloud-based schemes to edge computing solutions where nearby servers process requests in a timely manner. Virtualisation technologies have recently given data cloud and network providers the required flexibility to offer such on-demand resources. However, the maintenance of close computing resources presents a challenge when the served devices are on the move. In this case, if processing continuity is desired, a transference of processing resources and task state should be committed to maintain the service to end devices. The solution here presented, MIGRATE, proposes the concept of virtual mobile devices (vMDs) implemented as Virtual Functions (VxF) and acting as virtual representatives of physical processing devices. vMDs are instantiated at the edge of the access network, following a Multi-Access Edge Computing (MEC) approach, and move across different virtualisation domains. MIGRATE provides seamless and efficient transference of these software entities to follow the real location of mobile devices and continue supporting their physical counterparts. Software Defined Networks and Management and Operation functions are exploited to “migrate” vMDs to new virtualisation domains by forwarding data flows to the former domain until the new one is prepared, while a distributed data base avoids the transference of data. The solution has been deployed in a reference vehicular scenario at the Institute of Telecommunications Aveiro premises within the 5GINFIRE European project. In particular, the system has been evaluated under different virtualisation domains to study the operation of the migration approach in a vehicular monitoring scenario. The results validate the system from the application viewpoint with a Web monitoring tool, and the migration of the digital twin provided as VxF is analysed attending to the modification of data flows, indicating a seamless transition between virtualisation domains in a timely manner.publishe
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