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Monika Frenger, Werner Pitsch, Eike Emrich
In cooperation with the Sports Association of the Palatinate (SBP), a survey was conducted on substance use by recreational and amateur athletes. Distribution of the online questionnaire took place by means of chain-referral sampling, and questions on substance use were presented using the randomized response technique (RRT) to protect the anonymity of respondents and prevent socially desirable answers. The estimated lowest limit for the population share for use of prohibited substances during the last season (4%) and for lifetime use (3...
2016: PloS One
Bruno C L Macena, Fábio H V Hazin
Whale sharks are generally associated with environmental factors that drive their movements to specific locations where food availability is high. Consequently, foraging is believed to be the main reason for the formation of whale shark aggregations. Feeding aggregations occur mainly in nearshore areas and are composed primarily of immature individuals. Conversely, aggregations of mature adults are rarely observed, and their occurrence is correlated with oceanic environments. Despite an increase in the number of whale shark studies, information on mating and parturition grounds is still lacking...
2016: PloS One
Michael Worobey, Thomas D Watts, Richard A McKay, Marc A Suchard, Timothy Granade, Dirk E Teuwen, Beryl A Koblin, Walid Heneine, Philippe Lemey, Harold W Jaffe
The emergence of HIV-1 group M subtype B in North American men who have sex with men was a key turning point in the HIV/AIDS pandemic. Phylogenetic studies have suggested cryptic subtype B circulation in the United States (US) throughout the 1970s and an even older presence in the Caribbean. However, these temporal and geographical inferences, based upon partial HIV-1 genomes that postdate the recognition of AIDS in 1981, remain contentious and the earliest movements of the virus within the US are unknown. We serologically screened >2,000 1970s serum samples and developed a highly sensitive approach for recovering viral RNA from degraded archival samples...
October 26, 2016: Nature
George A Prenosil, Bernd Klaeser, Michael Hentschel, Markus Fürstner, Michael Berndt, Thomas Krause, Thilo Weitzel
PURPOSE: A PET/CT system's imaging capabilities are best described by its point spread function (PSF) in the spatial domain or equivalently by its modulation transfer function (MTF) in the spatial frequency domain. Knowing PSFs or MTFs is a prerequisite for many numerical methods attempting to improve resolution and to reduce the partial volume effect. In PET/CT, the observed PSF is a convolution of the system's intrinsic imaging capabilities including image reconstruction (PSF0) and the positron range function (PRF) of the imaged β(+) emitting isotope...
October 2016: Medical Physics
Joubin Nasehi Tehrani, Alistair McEwan, Jing Wang
PURPOSE: The authors have developed and evaluated a method to predict lung surface motion based on spirometry measurements, and chest and abdomen motion at selected locations. METHODS: A patient-specific 3D triangular surface mesh of the lung region was obtained at the end expiratory phase by the threshold-based segmentation method. Lung flow volume changes were recorded with a spirometer for each patient. A total of 192 selected points at a regular spacing of 2 × 2 cm matrix points were used to detect chest wall motion over a total area of 32 × 24 cm covering the chest and abdomen surfaces...
October 2016: Medical Physics
Pablo Mínguez, Glenn Flux, José Genollá, Alejandro Delgado, Emilia Rodeño, Katarina Sjögreen Gleisner
PURPOSE: To investigate the possible differences between SPECT/CT based whole-remnant and maximum-voxel dosimetry in patients receiving radio-iodine ablation treatment of differentiated thyroid cancer (DTC). METHODS: Eighteen DTC patients were administered 1.11 GBq of (131)I-NaI after near-total thyroidectomy and rhTSH stimulation. Two patients had two remnants, so in total dosimetry was performed for 20 sites. Three SPECT/CT scans were performed for each patient at 1, 2, and 3-7 days after administration...
October 2016: Medical Physics
Yicun Ni, J L Skinner
No man's land is the region in the metastable phase diagram of water where it is very difficult to do experiments on liquid water because of homogeneous nucleation to the crystal. There are a number of estimates of the location in no man's land of the liquid-liquid critical point, if it exists. We suggest that published IR absorption experiments on water droplets in no man's land can provide information about the correct location. To this end, we calculate theoretical IR spectra for liquid water over a wide range of temperatures and pressures, using our E3B3 model, and use the results to argue that the temperature dependence of the experimental spectra is inconsistent with several of the estimated critical point locations, but consistent with others...
September 28, 2016: Journal of Chemical Physics
Max Boleininger, Anne Ay Guilbert, Andrew P Horsfield
To interpret ultrafast dynamics experiments on large molecules, computer simulation is required due to the complex response to the laser field. We present a method capable of efficiently computing the static electronic response of large systems to external electric fields. This is achieved by extending the density-functional tight binding method to include larger basis sets and by multipole expansion of the charge density into electrostatically interacting Gaussian distributions. Polarizabilities for a range of hydrocarbon molecules are computed for a multipole expansion up to quadrupole order, giving excellent agreement with experimental values, with average errors similar to those from density functional theory, but at a small fraction of the cost...
October 14, 2016: Journal of Chemical Physics
Joel D Leger, Clyde Varner, Igor V Rubtsov
Fifth-order multidimensional infrared spectroscopy with heterodyned detection was carried out in the three-beam dual-frequency configuration. Numerous 5th-order cross peaks were detected for the 4-azidobutyrate-N-hydroxysuccinimide ester compound in solution involving several vibrational modes ranging in frequency from 1045 to 2100 cm(-1). Cross peaks involving overtones (2X/Z) and combination bands (XY/Z) among the tags, modes X and Y excited by the first two mid-IR laser pulses, and the reporter, modes Z excited by the third laser pulse, were acquired and the factors affecting the amplitude of 5th-order cross peaks are discussed...
October 21, 2016: Journal of Chemical Physics
H Pathak, J C Palmer, D Schlesinger, K T Wikfeldt, J A Sellberg, L G M Pettersson, A Nilsson
The thermodynamic response functions of water exhibit an anomalous increase upon cooling that becomes strongly amplified in the deeply supercooled regime due to structural fluctuations between disordered and tetrahedral local structures. Here, we compare structural data from recent x-ray laser scattering measurements of water at 1 bar and temperatures down to 227 K with structural properties computed for several different water models using molecular dynamics simulations. Based on this comparison, we critically evaluate four different thermodynamic scenarios that have been invoked to explain the unusual behavior of water...
October 7, 2016: Journal of Chemical Physics
Ji-Hang Zou, Zhen-Qiang Ye, Bing-Yang Cao
Phonon thermal transport in graphene has attracted significant interest in recent years. Phonon thermal properties of graphene are investigated by molecular dynamics simulations using the Tersoff, Tersoff-2010, REBO, and AIREBO potentials. By calculating the phonon properties and thermal conductivity of graphene, the performance of the potentials is evaluated based on comparisons with experimental data. It shows that the Tersoff-2010 and REBO display better dispersion curves for graphene than the original Tersoff and AIREBO...
October 7, 2016: Journal of Chemical Physics
Sutapa Roy, S Dietrich, Felix Höfling
The dynamic and static critical behavior of a family of binary Lennard-Jones liquid mixtures, close to their continuous demixing points (belonging to the so-called model H' dynamic universality class), are studied computationally by combining semi-grand canonical Monte Carlo simulations and large-scale molecular dynamics (MD) simulations, accelerated by graphic processing units (GPU). The symmetric binary liquid mixtures considered cover a variety of densities, a wide range of compressibilities, and various interactions between the unlike particles...
October 7, 2016: Journal of Chemical Physics
Hanwool Park, Choul-Gyun Lee
Microalgae have long been considered as one of most promising feedstocks with better characteristics for biofuels production over conventional energy crops. There have been a wide range of estimations on the feasibility of microalgal biofuels based on various productivity assumptions and data from different scales. The theoretical maximum algal biofuel productivity, however, can be calculated by the amount of solar irradiance and photosynthetic efficiency (PE), assuming other conditions are within the optimal range...
October 26, 2016: Biotechnology Journal
Gonçalo S Duarte, Mafalda Castelão, Filipe B Rodrigues, Raquel E Marques, Joaquim Ferreira, Cristina Sampaio, Austen P Moore, João Costa
BACKGROUND: This is an update of a Cochrane review first published in 2003. Cervical dystonia is the most common form of focal dystonia and is a disabling disorder characterised by painful involuntary head posturing. There are two available formulations of botulinum toxin, with botulinum toxin type A (BtA) usually considered the first line therapy for this condition. Botulinum toxin type B (BtB) is an alternative option, with no compelling theoretical reason why it might not be as- or even more effective - than BtA...
October 26, 2016: Cochrane Database of Systematic Reviews
Carmine Pinto, Lucia Mangone
The Italian Association of Medical Oncology (AIOM) and the Italian Association of Cancer Registries (AIRTUM) provide a reliable estimation of the incidence of cancer in Italy. The most outstanding data point to the steadily increasing efficacy of novel therapies, allowing patients to live longer and have a better quality of life, and the number of citizens being diagnosed with cancer - more than three million people, 4.9% of the population. Over the last years, a significant reduction in cancer incidence has been recorded among men with an opposite tendency among women...
October 2016: Recenti Progressi in Medicina
Yun-Jian Cheng, Wenge Qiu, Jin Lei
Tunnel lining (bare-lining) cross-sections play an important role in analyzing deformations of tunnel linings. The goal of this paper is to develop an automatic method for extracting bare-lining cross-sections from terrestrial laser scanning (TLS) point clouds. First, the combination of a 2D projection strategy and angle criterion is used for tunnel boundary point detection, from which we estimate the two boundary lines in the X-Y plane. The initial direction of the cross-sectional plane is defined to be orthogonal to one of the two boundary lines...
October 6, 2016: Sensors
Hongfeng Huang, Xi Yao, Jianyong Wu, Wenhan Peng, Jianghua Chen
AIMS: To investigate the area under the curve (AUC) of mycophenolic acid (MPA) in adult Chinese renal allograft recipients receiving concomitant enteric-coated mycophenolate sodium (EC-MPS) and cyclosporine (CsA) during the early post-transplant phase and to develop optimal model equations for estimation of the MPA area under the plasma concentration-time curve from 0 to 12 hours (AUC0-12h) using a limited-sampling strategy (LSS). METHODS: The present study enrolled 24 Chinese renal recipients treated with EC-MPS, CsA, and corticosteroid, from whom 24 serial blood samples were collected over 12 hours...
October 26, 2016: International Journal of Clinical Pharmacology and Therapeutics
Kateryna S Pantiukh, Nikolay N Chekanov, Igor V Zaigrin, Alexei M Zotov, Alexander M Mazur, Egor B Prokhortchouk
Concerns of traditional prenatal aneuploidy testing methods, such as low accuracy of noninvasive and health risks associated with invasive procedures, were overcome with the introduction of novel noninvasive methods based on genetics (NIPT). These were rapidly adopted into clinical practice in many countries after a series of successful trials of various independent submethods. Here we present results of own NIPT trial carried out in Moscow, Russia. 1012 samples were subjected to the method aimed at measuring chromosome coverage by massive parallel sequencing...
2016: F1000Research
M M Broadney, N Chahal, K A Michels, A C McLain, A Ghassabian, D A Lawrence, E H Yeung
BACKGROUND/OBJECTIVES: Maternal obesity may influence neonatal and childhood morbidities through increased inflammation and/or altered immune response. Less is known about paternal obesity. We hypothesized that excessive parental weight contributes to elevated inflammation and altered immunoglobulin (Ig) profiles in neonates. SUBJECTS/METHODS: In the Upstate KIDS Study maternal pre-pregnancy body mass index (BMI) was obtained from vital records and paternal BMI from maternal report...
October 26, 2016: International Journal of Obesity: Journal of the International Association for the Study of Obesity
Pawel Kuklik, Benjamin Schäffer, Boris A Hoffmann, Anand N Ganesan, Doreen Schreiber, Julia M Moser, Ruken Ö Akbulak, Arian Sultan, Daniel Steven, Bart Maesen, Ulrich Schotten, Christian Meyer, Stephan Willems
BACKGROUND: Electrogram-based identification of the regions maintaining persistent Atrial Fibrillation (AF) is a subject of ongoing debate. Here, we explore the concept of local electrical dyssynchrony to identify AF drivers. METHODS AND RESULTS: Local electrical dyssynchrony was calculated using mean phase coherence. High-density epicardial mapping along with mathematical model were used to explore the link between local dyssynchrony and properties of wave conduction...
2016: PloS One
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