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Biological Assessment of the Advanced Turbine Design at Wanapum Dam, 2005
This report summarizes the results of studies sponsored by the U.S. Department of Energy and conducted by Pacific Northwest National Laboratory to evaluate the biological performance (likelihood of injury to fish) from an advanced design turbine installed at Unit 8 of Wanapum Dam on the Columbia River in Washington State in 2005. PNNL studies included a novel dye technique to measure injury to juvenile fish in the field, an evaluation of blade-strike using both deterministic and stochastic models, and extended analysis of the response of the Sensor Fish Device to strike, pressure, and turbulence within the turbine system. Fluorescein dye was used to evaluate injuries to live fish passed through the advanced turbine and an existing turbine at two spill discharges (15 and 17 kcfs). Under most treatments the results were not significantly different for the two turbines, however, eye injury occurred in nearly 30% of fish passing through Unit 9 but in less than 10% of those passing through Unit 8 at 15 kcfs. Both deterministic and stochastic blade-strike models were applied for the original and new AHTS turbines. The modeled probabilities were compared to the Sensor Fish results (Carlson et al. 2006) and the biological studies using juvenile fish (Normandeau et al. 2005) under the same operational parameters. The new AHTS turbine had slightly higher modeled injury rates than the original turbine, but no statistical evidence to suggest that there is significant difference in blade-strike injury probabilities between the two turbines, which is consistent with the experiment results using Sensor Fish and juvenile fish. PNNL also conducted Sensor Fish studies at Wanapum Dam in 2005 concurrent with live fish studies. The probablility of severe collision events was similar for both turbine. The advanced turbine had a slightly lower probability of severe shear events but a slightly higher probability of slight shear
Electronic structure of the trilayer cuprate superconductor BiSrCaCuO
The low-energy electronic structure of the trilayer cuprate superconductor
BiSrCaCuO near optimal doping is investigated by
angle-resolved photoemission spectroscopy. The normal state quasiparticle
dispersion and Fermi surface, and the superconducting d-wave gap and coherence
peak are observed and compared with those of single and bilayer systems. We
find that both the superconducting gap magnitude and the relative
coherence-peak intensity scale linearly with for various optimally doped
materials. This suggests that the higher of the trilayer system should be
attributed to parameters that simultaneously enhance phase stiffness and
pairing strength.Comment: 5 pages, 5 figre
Framework, principles and recommendations for utilising participatory methodologies in the co-creation and evaluation of public health interventions
Background:
Due to the chronic disease burden on society, there is a need for preventive public health interventions to stimulate society towards a healthier lifestyle. To deal with the complex variability between individual lifestyles and settings, collaborating with end-users to develop interventions tailored to their unique circumstances has been suggested as a potential way to improve effectiveness and adherence. Co-creation of public health interventions using participatory methodologies has shown promise but lacks a framework to make this process systematic. The aim of this paper was to identify and set key principles and recommendations for systematically applying participatory methodologies to co-create and evaluate public health interventions.
Methods:
These principles and recommendations were derived using an iterative reflection process, combining key learning from published literature in addition to critical reflection on three case studies conducted by research groups in three European institutions, all of whom have expertise in co-creating public health interventions using different participatory methodologies.
Results:
Key principles and recommendations for using participatory methodologies in public health intervention co-creation are presented for the stages of: Planning (framing the aim of the study and identifying the appropriate sampling strategy); Conducting (defining the procedure, in addition to manifesting ownership); Evaluating (the process and the effectiveness) and Reporting (providing guidelines to report the findings). Three scaling models are proposed to demonstrate how to scale locally developed interventions to a population level.
Conclusions:
These recommendations aim to facilitate public health intervention co-creation and evaluation utilising participatory methodologies by ensuring the process is systematic and reproducible
Acute coronary syndrome: What do patients know?
Background: The effectiveness of therapy for an acute coronary syndrome (ACS) is dependent on patients' quick decision to seek treatment. We surveyed patients' level of knowledge about heart disease and self-perceived risk for a future acute myocardial infarction (AMI) in patients with documented ischemic heart disease. Methods: Patients (N = 3522) had a mean age of 67 years, 68% were male, and all had a history of AMI or invasive cardiac procedure for ischemic heart disease. Data were gathered using a 26-item instrument focusing on ACS symptoms and appropriate steps to seeking treatment. Patients were asked to identify their level of perceived risk for a future AMI. Results: Forty-six percent of patients had low knowledge levels (ie, <70% of answers were correct). The mean score was 71%. Higher knowledge scores were significantly related to female sex (P = .001), younger age (P = .001), higher education (P = .001), participation in cardiac rehabilitation (P = .001), and receiving care by a cardiologist rather than an internist or general practitioner (P = .005). Clinical history (eg, AMI [P = .24] and cardiac surgery [P = .38]) were not significant predictors of knowledge. Most (57%) identified themselves as being at higher risk for a future AMI compared with an age-matched individual without heart disease with 1 exception. Namely, patients who had undergone coronary artery bypass surgery felt significantly less vulnerable for a future AMI than other individuals of the same age. Conclusions: Even following diagnosis of ACS and numerous interactions with physicians and other health care professionals, knowledge about ACS symptoms and treatment on the part of patients with cardiac disease remains poor. Patients require continued reinforcement about the nature of cardiac symptoms, the benefits of early treatment, and their risk status. ©2008 American Medical Association. All rights reserved
Stripes, Vibrations and Superconductivity
We propose a model of a spatially modulated collective charge state of
superconducting cuprates. The regions of higher carrier density (stripes) are
described in terms of Luttinger liquids and the regions of lower density as a
two-dimensional interacting bosonic gas of d_{x^2-y^2} hole pairs. The
interactions among the elementary excitations are repulsive and the transition
to the superconducting state is driven by decay processes. Vibrations of the
CCS and the lattice, although not participating directly in the binding
mechanism, are fundamental for superconductivity. The superfluid density and
the lattice have a strong tendency to modulation implying a still unobserved
dimerized stripe phase in cuprates. The phase diagram of the model has a
crossover from 1D to 2D behavior and a pseudogap region where the amplitude of
the order parameters are finite but phase coherence is not established. We
discuss the nature of the spin fluctuations and the unusual isotope effect
within the model.Comment: 51 pages, 20 figures. Post-March Meeting version: New references are
added, some of the typos are corrected, and a few new discussions are
include
(S)Partners for Heart Health: a school-based program for enhancing physical activity and nutrition to promote cardiovascular health in 5th grade students
Osteo-Chondroprogenitor–Specific Deletion of the Selenocysteine tRNA Gene, Trsp, Leads to Chondronecrosis and Abnormal Skeletal Development: A Putative Model for Kashin-Beck Disease
Kashin-Beck disease, a syndrome characterized by short stature, skeletal deformities, and arthropathy of multiple joints, is highly prevalent in specific regions of Asia. The disease has been postulated to result from a combination of different environmental factors, including contamination of barley by mold mycotoxins, iodine deficiency, presence of humic substances in drinking water, and, importantly, deficiency of selenium. This multifunctional trace element, in the form of selenocysteine, is essential for normal selenoprotein function, including attenuation of excessive oxidative stress, and for the control of redox-sensitive molecules involved in cell growth and differentiation. To investigate the effects of skeletal selenoprotein deficiency, a Cre recombinase transgenic mouse line was used to trigger Trsp gene deletions in osteo-chondroprogenitors. Trsp encodes selenocysteine tRNA[Ser]Sec, required for the incorporation of selenocysteine residues into selenoproteins. The mutant mice exhibited growth retardation, epiphyseal growth plate abnormalities, and delayed skeletal ossification, as well as marked chondronecrosis of articular, auricular, and tracheal cartilages. Phenotypically, the mice thus replicated a number of the pathological features of Kashin-Beck disease, supporting the notion that selenium deficiency is important to the development of this syndrome
LSST: from Science Drivers to Reference Design and Anticipated Data Products
(Abridged) We describe here the most ambitious survey currently planned in
the optical, the Large Synoptic Survey Telescope (LSST). A vast array of
science will be enabled by a single wide-deep-fast sky survey, and LSST will
have unique survey capability in the faint time domain. The LSST design is
driven by four main science themes: probing dark energy and dark matter, taking
an inventory of the Solar System, exploring the transient optical sky, and
mapping the Milky Way. LSST will be a wide-field ground-based system sited at
Cerro Pach\'{o}n in northern Chile. The telescope will have an 8.4 m (6.5 m
effective) primary mirror, a 9.6 deg field of view, and a 3.2 Gigapixel
camera. The standard observing sequence will consist of pairs of 15-second
exposures in a given field, with two such visits in each pointing in a given
night. With these repeats, the LSST system is capable of imaging about 10,000
square degrees of sky in a single filter in three nights. The typical 5
point-source depth in a single visit in will be (AB). The
project is in the construction phase and will begin regular survey operations
by 2022. The survey area will be contained within 30,000 deg with
, and will be imaged multiple times in six bands, ,
covering the wavelength range 320--1050 nm. About 90\% of the observing time
will be devoted to a deep-wide-fast survey mode which will uniformly observe a
18,000 deg region about 800 times (summed over all six bands) during the
anticipated 10 years of operations, and yield a coadded map to . The
remaining 10\% of the observing time will be allocated to projects such as a
Very Deep and Fast time domain survey. The goal is to make LSST data products,
including a relational database of about 32 trillion observations of 40 billion
objects, available to the public and scientists around the world.Comment: 57 pages, 32 color figures, version with high-resolution figures
available from https://www.lsst.org/overvie
Measurement of the cross-section and charge asymmetry of bosons produced in proton-proton collisions at TeV with the ATLAS detector
This paper presents measurements of the and cross-sections and the associated charge asymmetry as a
function of the absolute pseudorapidity of the decay muon. The data were
collected in proton--proton collisions at a centre-of-mass energy of 8 TeV with
the ATLAS experiment at the LHC and correspond to a total integrated luminosity
of 20.2~\mbox{fb^{-1}}. The precision of the cross-section measurements
varies between 0.8% to 1.5% as a function of the pseudorapidity, excluding the
1.9% uncertainty on the integrated luminosity. The charge asymmetry is measured
with an uncertainty between 0.002 and 0.003. The results are compared with
predictions based on next-to-next-to-leading-order calculations with various
parton distribution functions and have the sensitivity to discriminate between
them.Comment: 38 pages in total, author list starting page 22, 5 figures, 4 tables,
submitted to EPJC. All figures including auxiliary figures are available at
https://atlas.web.cern.ch/Atlas/GROUPS/PHYSICS/PAPERS/STDM-2017-13
Search for chargino-neutralino production with mass splittings near the electroweak scale in three-lepton final states in √s=13 TeV pp collisions with the ATLAS detector
A search for supersymmetry through the pair production of electroweakinos with mass splittings near the electroweak scale and decaying via on-shell W and Z bosons is presented for a three-lepton final state. The analyzed proton-proton collision data taken at a center-of-mass energy of √s=13 TeV were collected between 2015 and 2018 by the ATLAS experiment at the Large Hadron Collider, corresponding to an integrated luminosity of 139 fb−1. A search, emulating the recursive jigsaw reconstruction technique with easily reproducible laboratory-frame variables, is performed. The two excesses observed in the 2015–2016 data recursive jigsaw analysis in the low-mass three-lepton phase space are reproduced. Results with the full data set are in agreement with the Standard Model expectations. They are interpreted to set exclusion limits at the 95% confidence level on simplified models of chargino-neutralino pair production for masses up to 345 GeV
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