554 research outputs found
Superconducting Properties of MgCNi3 Films
We report the magnetotransport properties of thin polycrystalline films of
the recently discovered non-oxide perovskite superconductor MgCNi3. CNi3
precursor films were deposited onto sapphire substrates and subsequently
exposed to Mg vapor at 700 C. We report transition temperatures (Tc) and
critical field values (Hc2) of MgCNi3 films ranging in thickness from 7.5 nm to
100 nm. Films thicker than ~40 nm have a Tc ~ 8 K, and an upper critical field
Hc2 ~ 14 T, which are both comparable to that of polycrystalline powders. Hall
measurements in the normal state give a carrier density, n =-4.2 x 10^22 cm^-3,
that is approximately 4 times that reported for bulk samples.Comment: submitted to PR
Structural Analysis of Narratives with the Coq Proof Assistant
Abstract. This paper proposes a novel application of Interactive Proof Assistants for studying the formal properties of Narratives, building on recent work demonstrating the suitability of Intuitionistic Linear Logic as a conceptual model. More specifically, we describe a method for modelling narrative resources and actions, together with constraints on the story endings in the form of an ILL sequent. We describe how well-formed narratives can be interpreted from cut-free proof trees of the sequent obtained using Coq. We finally describe how to reason about narratives at the structural level using Coq: by allowing to prove 2nd order properties on the set of all the proofs generated by a sequent, Coq assists the verification of structural narrative properties traversing all possible variants of a given plot
Gene Expression of Human Lung Cancer Cell Line CL1-5 in Response to a Direct Current Electric Field
Background: Electrotaxis is the movement of adherent living cells in response to a direct current (dc) electric field (EF) of physiological strength. Highly metastatic human lung cancer cells, CL1-5, exhibit directional migration and orientation under dcEFs. To understand the transcriptional response of CL1-5 cells to a dcEF, microarray analysis was performed in this study. Methodology/Principal Findings: A large electric-field chip (LEFC) was designed, fabricated, and used in this study. CL1-5 cells were treated with the EF strength of 0mV/mm (the control group) and 300mV/mm (the EF-treated group) for two hours. Signaling pathways involving the genes that expressed differently between the two groups were revealed. It was shown that the EF-regulated genes highly correlated to adherens junction, telomerase RNA component gene regulation, and tight junction. Some up-regulated genes such as ACVR1B and CTTN, and some down-regulated genes such as PTEN, are known to be positively and negatively correlated to cell migration, respectively. The protein-protein interactions of adherens junction-associated EF-regulated genes suggested that platelet-derived growth factor (PDGF) receptors and ephrin receptors may participate in sensing extracellular electrical stimuli. We further observed a high percentage of significantly regulated genes which encode cell membrane proteins, suggesting that dcEF may directly influence the activity of cell membrane proteins in signal transduction. Conclusions/Significance: In this study, some of the EF-regulated genes have been reported to be essential whereas others are novel for electrotaxis. Our result confirms that the regulation of gene expression is involved in the mechanism of electrotactic response
Search for sterile neutrino oscillation using RENO and NEOS data
We present a reactor model independent search for sterile neutrino
oscillation using 2\,509\,days of RENO near detector data and 180 days of NEOS
data. The reactor related systematic uncertainties are significantly suppressed
as both detectors are located at the same reactor complex of Hanbit Nuclear
Power Plant. The search is performed by electron
antineutrino\,() disappearance between six reactors and two
detectors with baselines of 294\,m\,(RENO) and 24\,m\,(NEOS). A spectral
comparison of the NEOS prompt-energy spectrum with a no-oscillation prediction
from the RENO measurement can explore reactor oscillations
to sterile neutrino. Based on the comparison, we obtain a 95\% C.L. excluded
region of \,eV. We also obtain a 68\% C.L. allowed
region with the best fit of \,eV and
=0.080.03 with a p-value of 8.2\%. Comparisons of
obtained reactor antineutrino spectra at reactor sources are made among RENO,
NEOS, and Daya Bay to find a possible spectral variation.Comment: 6 pages, 5 figures: This manuscript has been significantly revised by
the joint reanalysis by RENO and NEOS Collaborations. (In the previous
edition, the RENO collaboration used publicly available NEOS data to evaluate
the expected neutrino spectrum at NEOS.
Monte Carlo Methods for Estimating Interfacial Free Energies and Line Tensions
Excess contributions to the free energy due to interfaces occur for many
problems encountered in the statistical physics of condensed matter when
coexistence between different phases is possible (e.g. wetting phenomena,
nucleation, crystal growth, etc.). This article reviews two methods to estimate
both interfacial free energies and line tensions by Monte Carlo simulations of
simple models, (e.g. the Ising model, a symmetrical binary Lennard-Jones fluid
exhibiting a miscibility gap, and a simple Lennard-Jones fluid). One method is
based on thermodynamic integration. This method is useful to study flat and
inclined interfaces for Ising lattices, allowing also the estimation of line
tensions of three-phase contact lines, when the interfaces meet walls (where
"surface fields" may act). A generalization to off-lattice systems is described
as well.
The second method is based on the sampling of the order parameter
distribution of the system throughout the two-phase coexistence region of the
model. Both the interface free energies of flat interfaces and of (spherical or
cylindrical) droplets (or bubbles) can be estimated, including also systems
with walls, where sphere-cap shaped wall-attached droplets occur. The
curvature-dependence of the interfacial free energy is discussed, and estimates
for the line tensions are compared to results from the thermodynamic
integration method. Basic limitations of all these methods are critically
discussed, and an outlook on other approaches is given
PD-1 blockade in recurrent or metastatic cervical cancer: Data from cemiplimab phase I expansion cohorts and characterization of PD-L1 expression in cervical cancer
Objectives: To characterize the safety, tolerability, and anti-tumor activity of cemiplimab as monotherapy or in combination with hypofractionated radiation therapy (hfRT) in patients with recurrent or metastatic cervical cancer. To determine the association between histology and programmed death-ligand 1 (PD-L1) expression.
Methods: In non-randomized phase I expansion cohorts, patients (squamous or non-squamous histology) received cemiplimab 3 mg/kg intravenously every 2 weeks for 48 weeks, either alone (monotherapy cohort) or with hfRT during week 2 (combination cohort). Due to insufficient tissue material, PD-L1 protein expression was evaluated in commercially purchased samples and mRNA expression levels were analyzed from The Cancer Genome Atlas (TCGA).
Results: Twenty patients enrolled in both cohorts in total; 10 had squamous histology. The most common adverse events of any grade were diarrhea, fatigue, and hypokalemia, occurring in 35%, 25%, and 25%, respectively. Objective response rate was 10% in each cohort; responders had squamous histology. Duration of response was 11.2 months and 6.4 months for the responder in the monotherapy and combination cohort, respectively. Irradiated lesions were not included in the response assessments. In separate archived specimens (N = 155), PD-L1 protein expression in tumor and immune cells was negative (<1%) more commonly in adenocarcinoma than in squamous tumors. PD-L1 mRNA levels were lower in adenocarcinoma than squamous cell tumors (1.2 vs 5.0 mean transcripts per million, respectively) in TCGA.
Conclusions: Cemiplimab has activity in cervical squamous cell carcinoma. The phase I results, combined with results from other anti-PD-1 trials in cervical cancer and our biomarker analyses have informed the design of the ongoing phase III trial, with the primary overall survival hierarchical analyses being done first in patients with squamous histology
Shrinking a large dataset to identify variables associated with increased risk of Plasmodium falciparum infection in Western Kenya
Large datasets are often not amenable to analysis using traditional single-step approaches. Here, our general objective was to apply imputation techniques, principal component analysis (PCA), elastic net and generalized linear models to a large dataset in a systematic approach to extract the most meaningful predictors for a health outcome. We extracted predictors for Plasmodium falciparum infection, from a large covariate dataset while facing limited numbers of observations, using data from the People, Animals, and their Zoonoses (PAZ) project to demonstrate these techniques: data collected from 415 homesteads in western Kenya, contained over 1500 variables that describe the health, environment, and social factors of the humans, livestock, and the homesteads in which they reside. The wide, sparse dataset was simplified to 42 predictors of P. falciparum malaria infection and wealth rankings were produced for all homesteads. The 42 predictors make biological sense and are supported by previous studies. This systematic data-mining approach we used would make many large datasets more manageable and informative for decision-making processes and health policy prioritization
Measurement of the B0-anti-B0-Oscillation Frequency with Inclusive Dilepton Events
The - oscillation frequency has been measured with a sample of
23 million \B\bar B pairs collected with the BABAR detector at the PEP-II
asymmetric B Factory at SLAC. In this sample, we select events in which both B
mesons decay semileptonically and use the charge of the leptons to identify the
flavor of each B meson. A simultaneous fit to the decay time difference
distributions for opposite- and same-sign dilepton events gives ps.Comment: 7 pages, 1 figure, submitted to Physical Review Letter
Morphology and Photoluminescence of HfO2Obtained by Microwave-Hydrothermal
In this letter, we report on the obtention of hafnium oxide (HfO2) nanostructures by the microwave-hydrothermal method. These nanostructures were analyzed by X-ray diffraction (XRD), field-emission gum scanning electron microscopy (FEG-SEM), transmission electron microscopy (TEM), energy dispersive X-ray spectrometry (EDXS), ultraviolet–visible (UV–vis) spectroscopy, and photoluminescence (PL) measurements. XRD patterns confirmed that this material crystallizes in a monoclinic structure. FEG-SEM and TEM micrographs indicated that the rice-like morphologies were formed due to an increase in the effective collisions between the nanoparticles during the MH processing. The EDXS spectrum was used to verify the chemical compositional of this oxide. UV–vis spectrum revealed that this material have an indirect optical band gap. When excited with 488 nm wavelength at room temperature, the HfO2nanostructures exhibited only one broad PL band with a maximum at around 548 nm (green emission)
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