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Models for the Prediction of the Thermal
Five models and eq\1ationsJorthe.predictic;>nof the tbertnal conduc~"ities of powders in the
literature are compared with the data obtainedill the experiments of the authors. Anew modified
ntodel for the. correlation of the experimental data is presented.
Key words: differential scanning calorimetry, porosity, solid content, specific heat, thermal
conductivity.Mechanical Engineerin
Method to Annotate Arrhythmias by Deep Network
This study targets to automatically annotate on arrhythmia by deep network.
The investigated types include sinus rhythm, asystole (Asys), supraventricular
tachycardia (Tachy), ventricular flutter or fibrillation (VF/VFL), ventricular
tachycardia (VT). Methods: 13s limb lead ECG chunks from MIT malignant
ventricular arrhythmia database (VFDB) and MIT normal sinus rhythm database
were partitioned into subsets for 5-fold cross validation. These signals were
resampled to 200Hz, filtered to remove baseline wandering, projected to 2D gray
spectrum and then fed into a deep network with brand-new structure. In this
network, a feature vector for a single time point was retrieved by residual
layers, from which latent representation was extracted by variational
autoencoder (VAE). These front portions were trained to meet a certain
threshold in loss function, then fixed while training procedure switched to
remaining bidirectional recurrent neural network (RNN), the very portions to
predict an arrhythmia category. Attention windows were polynomial lumped on RNN
outputs for learning from details to outlines. And over sampling was employed
for imbalanced data. The trained model was wrapped into docker image for
deployment in edge or cloud. Conclusion: Promising sensitivities were achieved
in four arrhythmias and good precision rates in two ventricular arrhythmias
were also observed. Moreover, it was proven that latent representation by VAE,
can significantly boost the speed of convergence and accuracy
Adult Repellency and Larvicidal Activity of Five Plant Essential Oils Against Mosquitoes
The larvicidal activity and repellency of 5 plant essential oilsâthyme oil, catnip oil, amyris oil, eucalyptus oil, and cinnamon oilâwere tested against 3 mosquito species: Aedes albopictus, Ae. aegypti, and Culex pipiens pallens. Larvicidal activity of these essentials oils was evaluated in the laboratory against 4th instars of each of the 3 mosquito species, and amyris oil demonstrated the greatest inhibitory effect with LC50 values in 24 h of 58 ”g/ml (LC90 â=â 72 ”g/ml) for Ae. aegypti, 78 ”g/ml (LC90 â=â 130 ”g/ml) for Ae. albopictus, and 77 ”g/ml (LC90 â=â 123 ”g/ml) for Cx. p. pallens. The topical repellency of these selected essential oils and deet against laboratory-reared female blood-starved Ae. albopictus was examined. Catnip oil seemed to be the most effective and provided 6-h protection at both concentrations tested (23 and 468 ”g/cm2). Thyme oil had the highest effectiveness in repelling this species, but the repellency duration was only 2 h. The applications using these natural product essential oils in mosquito control are discussed
Hypoxia-inducible factor-1 α/platelet derived growth factor axis in HIV-associated pulmonary vascular remodeling
<p>Abstract</p> <p>Background</p> <p>Human immunodeficiency virus (HIV) infected patients are at increased risk for the development of pulmonary arterial hypertension (PAH). Recent reports have demonstrated that HIV associated viral proteins induce reactive oxygen species (ROS) with resultant endothelial cell dysfunction and related vascular injury. In this study, we explored the impact of HIV protein induced oxidative stress on production of hypoxia inducible factor (HIF)-1α and platelet-derived growth factor (PDGF), critical mediators implicated in the pathogenesis of HIV-PAH.</p> <p>Methods</p> <p>The lungs from 4-5 months old HIV-1 transgenic (Tg) rats were assessed for the presence of pulmonary vascular remodeling and HIF-1α/PDGF-BB expression in comparison with wild type controls. Human primary pulmonary arterial endothelial cells (HPAEC) were treated with HIV-associated proteins in the presence or absence of pretreatment with antioxidants, for 24 hrs followed by estimation of ROS levels and western blot analysis of HIF-1α or PDGF-BB.</p> <p>Results</p> <p>HIV-Tg rats, a model with marked viral protein induced vascular oxidative stress in the absence of active HIV-1 replication demonstrated significant medial thickening of pulmonary vessels and increased right ventricular mass compared to wild-type controls, with increased expression of HIF-1α and PDGF-BB in HIV-Tg rats. The up-regulation of both HIF-1α and PDGF-B chain mRNA in each HIV-Tg rat was directly correlated with an increase in right ventricular/left ventricular+septum ratio. Supporting our <it>in-viv</it>o findings, HPAECs treated with HIV-proteins: Tat and gp120, demonstrated increased ROS and parallel increase of PDGF-BB expression with the maximum induction observed on treatment with R5 type gp-120<sub>CM</sub>. Pre-treatment of endothelial cells with antioxidants or transfection of cells with HIF-1α small interfering RNA resulted in abrogation of gp-120<sub>CM </sub>mediated induction of PDGF-BB, therefore, confirming that ROS generation and activation of HIF-1α plays critical role in gp120 mediated up-regulation of PDGF-BB.</p> <p>Conclusion</p> <p>In summary, these findings indicate that viral protein induced oxidative stress results in HIF-1α dependent up-regulation of PDGF-BB and suggests the possible involvement of this pathway in the development of HIV-PAH.</p
The Mass Distribution and Assembly of the Milky Way from the Properties of the Magellanic Clouds
We present a new measurement of the mass of the Milky Way (MW) based on
observed properties of its largest satellite galaxies, the Magellanic Clouds
(MCs), and an assumed prior of a {\Lambda}CDM universe. The large,
high-resolution Bolshoi cosmological simulation of this universe provides a
means to statistically sample the dynamical properties of bright satellite
galaxies in a large population of dark matter halos. The observed properties of
the MCs, including their circular velocity, distance from the center of the MW,
and velocity within the MW halo, are used to evaluate the likelihood that a
given halo would have each or all of these properties; the posterior PDF for
any property of the MW system can thus be constructed. This method provides a
constraint on the MW virial mass, 1.2 +0.7 -0.3(stat.) +0.3 -0.4 (sys.) x 10^12
M\odot (68% confidence), which is consistent with recent determinations that
involve very different assumptions. In addition, we calculate the posterior PDF
for the density profile of the MW and its satellite accretion history. Although
typical satellites of 10^12 M\odot halos are accreted over a wide range of
epochs over the last 10 Gyr, we find a \sim72% probability that the Magellanic
Clouds were accreted within the last Gyr, and a 50% probability that they were
accreted together.Comment: 9 pages, replaced with version published in ApJ. Animations available
at http://risa.stanford.edu/milkyway
On the Baryon Fractions in Clusters and Groups of Galaxies
We present the baryon fractions of 2MASS groups and clusters as a function of
cluster richness using total and gas masses measured from stacked ROSAT X-ray
data and stellar masses estimated from the infrared galaxy catalogs. We detect
X-ray emission even in the outskirts of clusters, beyond r_200 for richness
classes with X-ray temperatures above 1 keV. This enables us to more accurately
determine the total gas mass in these groups and clusters. We find that the
optically selected groups and clusters have flatter temperature profiles and
higher stellar-to-gas mass ratios than the individually studied, X-ray bright
clusters. We also find that the stellar mass in poor groups with temperatures
below 1 keV is comparable to the gas mass in these systems. Combining these
results with individual measurements for clusters, groups, and galaxies from
the literature, we find a break in the baryon fraction at ~1 keV. Above this
temperature, the baryon fraction scales with temperature as f_b \propto
T^0.20\pm0.03. We see significantly smaller baryon fractions below this
temperature, and the baryon fraction of poor groups joins smoothly onto that of
systems with still shallower potential wells such as normal and dwarf galaxies
where the baryon fraction scales with the inferred velocity dispersion as f_b
\propto \sigma^1.6. The small scatter in the baryon fraction at any given
potential well depth favors a universal baryon loss mechanism and a preheating
model for the baryon loss. The scatter is, however, larger for less massive
systems. Finally, we note that although the broken power-law relation can be
inferred from data points in the literature alone, the consistency between the
baryon fractions for poor groups and massive galaxies inspires us to fit the
two categories of objects (galaxies and clusters) with one relation.Comment: 21 pages, 5 figures, ApJ in pres
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