480 research outputs found
Anomalous Spin Dynamics observed by High Frequency ESR in Honeycomb Lattice Antiferromagnet InCu2/3V1/3O3
High-frequency ESR results on the S=1/2 Heisenberg hexagonal antiferromagnet
InCu2/3V1/3O3 are reported. This compound appears to be a rare model substance
for the honeycomb lattice antiferromagnet with very weak interlayer couplings.
The high-temperature magnetic susceptibility can be interpreted by the S=1/2
honeycomb lattice antiferromagnet, and it shows a magnetic-order-like anomaly
at TN=38 K. Although, the resonance field of our high-frequency ESR shows the
typical behavior of the antiferromagnetic resonance, the linewidth of our
high-frequency ESR continues to increase below TN, while it tends to decrease
as the temperature in a conventional three-dimensional antiferromagnet
decreases. In general, a honeycomb lattice antiferromagnet is expected to show
a simple antiferromagnetic order similar to that of a square lattice
antiferromagnet theoretically because both antiferromagnets are bipartite
lattices. However, we suggest that the observed anomalous spin dynamics below
TN is the peculiar feature of the honeycomb lattice antiferromagnet that is not
observed in the square lattice antiferromagnet.Comment: 5 pages, 5 figure
Erratum to: Benchmarks for ethically credible partnerships between industry and academic health centers: beyond disclosure of financial conflicts of interest.
Relationships between industry and university-based researchers have been commonplace for decades and have received notable attention concerning the conflicts of interest these relationships may harbor. While new efforts are being made to update conflict of interest policies and make industry relationships with academia more transparent, the development of broader institutional partnerships between industry and academic health centers challenges the efficacy of current policy to effectively manage these innovative partnerships. In this paper, we argue that existing strategies to reduce conflicts of interest are not sufficient to address the emerging models of industry-academic partnerships because they focus too narrowly on financial matters and are not comprehensive enough to mitigate all ethical risk. Moreover, conflict-of-interest strategies are not designed to promote best practices nor the scientific and social benefits of academic-industry collaboration. We propose a framework of principles and benchmarks for "ethically credible partnerships" between industry and academic health centers and describe how this framework may provide a practical and comprehensive approach for designing and evaluating such partnerships
Measuring the Impact of Quantitative Information on Patient Understanding: Approaches for Assessing the Adequacy of Patient Knowledge about Colorectal Cancer Screening
Background. Guidelines recommend that decision aids disclose quantitative information to patients considering colorectal cancer (CRC) screening, but the impact on patient knowledge and decision making is limited. An important challenge for assessing any disclosure involves determining when an individual has “adequate knowledge” to make a decision. Methods. We analyzed data from a trial that randomized 213 patients to view a decision aid about CRC screening that contained verbal information (qualitative arm) versus one containing verbal plus quantitative information (quantitative arm). We analyzed participants’ answers to 8 “qualitative knowledge” questions, which did not cover the quantitative information, at baseline (T0) and after viewing the decision aid (T1). We introduce a novel approach that defines adequate knowledge as correctly answering all of a subset of questions that are particularly relevant because of the participant’s test choice (“Choice-Based Knowledge Assessment”). Results. Participants in the quantitative arm answered a higher mean number of knowledge questions correctly at T1 than did participants in the qualitative arm (7.3 v. 6.9, P < 0.05), and they more frequently had adequate knowledge at T1 based on a cutoff of 6 or 7 correct out of 8 (94% v. 83%, P < 0.05, and 86% v. 71%, P < 0.05, respectively). Members of the quantitative group also more frequently had adequate knowledge at T1 when assessed by Choice-Based Knowledge Assessment (87% v. 76%, P < 0.05). Conclusions. Patients who viewed quantitative information in addition to verbal information had greater qualitative knowledge and more frequently had adequate knowledge compared with those who viewed verbal information alone, according to most ways of defining adequate knowledge. Quantitative information may have helped participants better understand qualitative or gist concepts
Bayesian Matrix Completion for Hypothesis Testing
High-throughput screening (HTS) is a well-established technology that rapidly
and efficiently screens thousands of chemicals for potential toxicity. Massive
testing using HTS primarily aims to differentiate active vs inactive chemicals
for different types of biological endpoints. However, even using
high-throughput technology, it is not feasible to test all possible
combinations of chemicals and assay endpoints, resulting in a majority of
missing combinations. Our goal is to derive posterior probabilities of activity
for each chemical by assay endpoint combination, addressing the sparsity of HTS
data. We propose a Bayesian hierarchical framework, which borrows information
across different chemicals and assay endpoints in a low-dimensional latent
space. This framework facilitates out-of-sample prediction of bioactivity
potential for new chemicals not yet tested. Furthermore, this paper makes a
novel attempt in toxicology to simultaneously model heteroscedastic errors as
well as a nonparametric mean function. It leads to a broader definition of
activity whose need has been suggested by toxicologists. Simulation studies
demonstrate that our approach shows superior performance with more realistic
inferences on activity than current standard methods. Application to an HTS
data set identifies chemicals that are most likely active for two disease
outcomes: neurodevelopmental disorders and obesity. Code is available on
Github
Crescent-Shaped Electron Distributions at the Nonreconnecting Magnetopause: Magnetospheric Multiscale Observations
International audienceCrescent-shaped electron distributions perpendicular to the magnetic field are an important indicator of the electron diffusion region in magnetic reconnection. They can be formed by the electron finite gyroradius effect at plasma boundaries or by demagnetized electron motion. In this study, we present Magnetospheric Multiscale mission observations of electron crescents at the flank magnetopause on 20 September 2017, where reconnection signatures are not observed. These agyrotropic electron distributions are generated by electron gyromotion at the thin electron-scale magnetic boundaries of a magnetic minimum after magnetic curvature scattering. The variation of their angular range in the perpendicular plane is in good agreement with predictions. Upper hybrid waves are observed to accompany the electron crescents at all four Magnetospheric Multiscale spacecraft as a result of the beam-plasma instability associated with these agyrotropic electron distributions. This study suggests electron crescents can be more frequently formed at the magnetopause. Plain Language Summary In this study, we present Magnetospheric Multiscale mission observations of electron crescents at the flank magnetopause and these agyrotropic electron distributions are formed at thin electron-scale magnetic boundaries after electron pitch angle scattering by the curved magnetic field. These results suggest that agyrotropic electron distributions can be more frequently formed at the magnetopause: (1) magnetic reconnection is not necessary, although electron crescents are taken as one of the observational signatures of the electron diffusion region, and (2) agyrotropic electron distributions can cover a large local time range to the flank magnetopause. In addition, upper hybrid waves accompanied with the electron crescents are observed as a result of the beam-plasma interaction associated with these agyrotropic electron distributions. This suggests that high-frequency waves play a role in electron dynamics through wave-particle interactions
Airway cells from atopic asthmatic patients exposed to ozone display an enhanced innate immune gene profile
This study identifies transcriptional phenotypes of sputum samples from normal volunteers and atopic asthmatics exposed to ozone. Network analyses suggest that asthmatics elevate immune signaling following oxidative stress, while nonasthmatics attempt to mitigate the ozone-induced response
Contamination Control and Assay Results for the Majorana Demonstrator Ultra Clean Components
The MAJORANA DEMONSTRATOR is a neutrinoless double beta decay experiment
utilizing enriched Ge-76 detectors in 2 separate modules inside of a common
solid shield at the Sanford Underground Research Facility. The DEMONSTRATOR has
utilized world leading assay sensitivities to develop clean materials and
processes for producing ultra-pure copper and plastic components. This
experiment is now operating, and initial data provide new insights into the
success of cleaning and processing. Post production copper assays after the
completion of Module 1 showed an increase in U and Th contamination in finished
parts compared to starting bulk material. A revised cleaning method and
additional round of surface contamination studies prior to Module 2
construction have provided evidence that more rigorous process control can
reduce surface contamination. This article describes the assay results and
discuss further studies to take advantage of assay capabilities for the purpose
of maintaining ultra clean fabrication and process design.Comment: Proceedings of Low Radioactivity Techniques (LRT May 2017, Seoul
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