2,639 research outputs found
Combination of large nanostructures and complex band structure for high performance thermoelectric lead telluride
The complexity of the valence band structure in p-type PbTe has been shown to enable a significant enhancement of the average thermoelectric figure of merit (zT) when heavily doped with Na. It has also been shown that when PbTe is nanostructured with large nanometer sized Ag_2Te precipitates there is an enhancement of zT due to phonon scattering at the interfaces. The enhancement in zT resulting from these two mechanisms is of similar magnitude but, in principle, decoupled from one another. This work experimentally demonstrates a successful combination of the complexity in the valence band structure with the addition of nanostructuring to create a high performance thermoelectric material. These effects lead to a high zT over a wide temperature range with peak zT > 1.5 at T > 650 K in Na-doped PbTe/Ag_2Te. This high average zT produces 30% higher efficiency (300â750 K) than pure Na-doped PbTe because of the nanostructures, while the complex valence band structure leads to twice the efficiency as the related n-type La-doped PbTe/Ag_2Te without such band structure complexity
Subrogation Claims in Insurance and the Real Party in Interest Statute
Subrogation Claims in Insurance and the Real Party in Interest Statut
Development of an Oral Care Protocol to Decrease Ventilator-Associated Pneumonia
The infectious disease nurses at Altru Health Care System informed the unit that I was working in that we had nine ventilator associated pneumonias in the past year in our unit and that the other intensive care unit had zero. I wanted to know why we had so many and the other unit didn\u27t have any so I started to do a literature search on ventilator related pneumonia. I found new research about the importance of oral care so I met with the representative from the company we used for oral care. He informed me that they had a line of products especially made for ventilator dependent patients
l completed a review of the literature and found that oral care does decrease the number of ventilator associated pneumonia. I decided then to develop a procedure for oral care for the ventilator dependent patient. I did a price comparison of what we were currently spending on oral care products and what we would spend if we implemented the line made for ventilated patients. I also investigated how much money that ventilator associated pneumonia ended up costing the patient and hospital. I presented the information I found to the infection control nurses and the managers of the two units were the new products would be implemented. They all signed agreed to proceed with the project. I met with the product committee to get approval for the new oral care line. They approved the new product and an implementation date was set. I planned an inservice day for all the staff of SCCU, ICU and the critical care float pool. The staff could come anytime during the clay and watch my presentation on the importance of oral care in ventilator dependent patients and get trained on the new product line. My anticipated results are that the number of ventilator associated pneumonias is decreased by using the product and doing oral care on ventilator dependent patient
Unsupervised Deep Single-Image Intrinsic Decomposition using Illumination-Varying Image Sequences
Machine learning based Single Image Intrinsic Decomposition (SIID) methods
decompose a captured scene into its albedo and shading images by using the
knowledge of a large set of known and realistic ground truth decompositions.
Collecting and annotating such a dataset is an approach that cannot scale to
sufficient variety and realism. We free ourselves from this limitation by
training on unannotated images.
Our method leverages the observation that two images of the same scene but
with different lighting provide useful information on their intrinsic
properties: by definition, albedo is invariant to lighting conditions, and
cross-combining the estimated albedo of a first image with the estimated
shading of a second one should lead back to the second one's input image. We
transcribe this relationship into a siamese training scheme for a deep
convolutional neural network that decomposes a single image into albedo and
shading. The siamese setting allows us to introduce a new loss function
including such cross-combinations, and to train solely on (time-lapse) images,
discarding the need for any ground truth annotations.
As a result, our method has the good properties of i) taking advantage of the
time-varying information of image sequences in the (pre-computed) training
step, ii) not requiring ground truth data to train on, and iii) being able to
decompose single images of unseen scenes at runtime. To demonstrate and
evaluate our work, we additionally propose a new rendered dataset containing
illumination-varying scenes and a set of quantitative metrics to evaluate SIID
algorithms. Despite its unsupervised nature, our results compete with state of
the art methods, including supervised and non data-driven methods.Comment: To appear in Pacific Graphics 201
Pseudo-distances on symplectomorphism groups and applications to flux theory
Starting from a given norm on the vector space of exact 1-forms of a compact
symplectic manifold, we produce pseudo-distances on its symplectomorphism group
by generalizing an idea due to Banyaga. We prove that in some cases (which
include Banyaga's construction), their restriction to the Hamiltonian
diffeomorphism group is equivalent to the distance induced by the initial norm
on exact 1-forms. We also define genuine "distances to the Hamiltonian
diffeomorphism group" which we use to derive several consequences, mainly in
terms of flux groups.Comment: 21 pages, no figure; v2. various typos corrected, some references
added. Published in Mathematische Zeitschrif
NDM-531: WIND TUNNEL TESTING OF RESIDENTIAL NEIGHBOURHOOD MODEL TO ANALYZE ROOF FAILURES IN HIGH WINDS
The EF-Scale estimates tornado wind speeds by the damage left in their wake, including the damage done to residential houses. The scale was developed based on an expert elicitation process, and so empirical testing is useful in determining its accuracy. Wind tunnel testing is often used to test low-rise buildings but building code configurations tend to be single, isolated houses, even though residential houses are much more common in suburban environments with many neighbouring buildings. The objective of this testing was to assess the roof-failure wind speeds for residential buildings in typical neighbourhood patterns and compare them to rural residence failure speeds and the EF-Scale. To this end, a 1:50 scale model of a suburban neighbourhood with 32 houses was built and tested in a wind tunnel. The effects of several variables such as wind direction and presence of dominant openings were also included in the study. After testing, it was concluded that neighbouring houses provided shielding and increased failure wind speeds in the range of 5 â 10%. Interestingly, when the shielding effects are considered, the range of failure wind speeds matches the range set out by the EF-Scale. Further work will analyze these points in greater detail
Revisiting the disappearance of terrestrial dissolved organic matter in the ocean : a delta C-13 study
Organic carbon (OC) depleted in C-13 is a widely used tracer for terrestrial organic matter (OM) in aquatic systems. Photochemical reactions can, however, change delta C-13 of dissolved organic carbon (DOC) when chromophoric, aromatic-rich terrestrial OC is selectively mineralized. We assessed the robustness of the delta C-13 signature of DOC (delta C-13(DOC)) as a tracer for terrestrial OM by estimating its change during the photobleaching of chromophoric DOM (CDOM) from 10 large rivers. These rivers cumulatively account for approximately one-third of the world's freshwater discharge to the global ocean. Photobleaching of CDOM by simulated solar radiation was associated with the photochemical mineralization of 16 to 43% of the DOC and, by preferentially removing compounds depleted in C-13, caused a 1 to 2.9 parts per thousand enrichment in delta C-13 in the residual DOC. Such solar-radiation-induced photochemical isotopic shift could bias the calculations of terrestrial OM discharge in coastal oceans towards the marine end-member. Shifts in terrestrial delta C-13(DOC) should be taken into account when constraining the terrestrial end-member in global calculation of terrestrially derived DOM in the world ocean.Peer reviewe
Porcine reproductive and respiratory syndrome virus whole-genome sequencing efficacy with field clinical samples using a poly(A)-tail viral genome purification method
The genomic surveillance of porcine reproductive and respiratory syndrome virus (PRRSV) is based on sequencing of the ORF5 gene of the virus, which covers only 4% of the entire viral genome. It is expected that PRRSV whole-genome sequencing (WGS) will improve PRRSV genomic data and allow better understanding of clinical discrepancies observed in the field when using ORF5 sequencing. Our main objective was to implement an efficient method for WGS of PRRSV from clinical samples. The viral genome was purified using a poly(A)-tail viral genome purification method and sequenced using Illumina technology. We tested 149 PRRSV-positive samples: 80 sera, 33 lungs, 33 pools of tissues, 2 oral fluids, and 1 processing fluid (i.e., castration liquid). Overall, WGS of 67.1% of PRRSV-positive cases was successful. The viral load, in particular for tissues, had a major impact on the PRRSV WGS success rate. Serum was the most efficient type of sample to conduct PRRSV WGS poly(A)-tail assays, with a success rate of 76.3%, and this result can be explained by improved sequencing reads dispersion matching throughout the entire viral genome. WGS was unsuccessful for all pools of tissue and lung samples with Cq values > 26.5, whereas it could still be successful with sera at Cq †34.1. Evaluation of results of highly qualified personnel confirmed that laboratory skills could affect PRRSV WGS efficiency. Oral fluid samples seem very promising and merit further investigation because, with only 2 samples of low viral load (Cq = 28.8, 32.8), PRRSV WGS was successful
Whole genome sequencing of porcine reproductive and respiratory syndrome virus 2 (PRRSV) from field clinical samples improves the genomic surveillance of the virus
Porcine reproductive and respiratory syndrome virus (PRRSV) is a major
economic concern worldwide. There are currently large data sets available about the
ORF5 gene of the virus, with thousands of sequences available, but little data are
currently available on the full-length genome of PRRSV. We hypothesized that
whole-genome sequencing (WGS) of the PRRSV genome would allow better epidemiological monitoring than ORF5 gene sequencing. PRRSV PCR-positive serum, oral
fluid, and tissue clinical samples submitted to the diagnostic laboratory for routine
surveillance or diagnosis of PRRSV infection in Québec, Canada, swine herds were
used. The PRRSV reverse transcription-quantitative PCR Cq values of the processed
samples varied between 11.5 and 34.34. PRRSV strain genomes were isolated using a
poly (A)-tail method and were sequenced with a MiSeq Illumina sequencer. Ninetytwo full-length PRRSV genomes were obtained from 88 clinical samples out of 132
tested samples, resulting in a PRRSV WGS success rate of 66.67%. Three important
deletions in ORF1a were found in most wild-type (i.e., not vaccine-like) strains. The
importance of these deletions remains undetermined. Two different full-length
PRRSV genomes were found in four different samples (three serum samples and one
pool of tissues), suggesting a 4.55% PRRSV strain coinfection prevalence in swine.
Moreover, six PRRSV whole genomes (6.52% of PRRSV strains) were found to cluster
differently than they did under the ORF5 classification method. Overall, WGS of
PRRSV enables better strain classification and/or interpretation of results in 9.10% of
clinical samples than ORF5 sequencing, as well as allowing interesting research avenues
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