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A Raman spectroscopic study of carbon phases in impact melt rocks and breccias from the Gardnos impact structure, Norway
Raman spectroscopy suggests that the C was emplaced in at least two separate episodes into the impactites of the Gardnos impact structure
Clinical, histological and prognostic features of a novel nail-bed lesion of cats: 41 cases
There is a distinct subset of lesions arising on the digits of cats, located at or close to the nail-bed epithelium, which are typically composed of proliferative fibroblast-like cells, multinucleate giant cells and areas of osseous metaplasia, but currently there is no published literature detailing the clinical or histological features of these lesions. This study identified 41 such cases from two large commercial diagnostic laboratories and assessed various histological and clinical features; 22 cases had additional follow-up data available
Loschmidt echoes in two-body random matrix ensembles
Fidelity decay is studied for quantum many-body systems with a dominant
independent particle Hamiltonian resulting e.g. from a mean field theory with a
weak two-body interaction. The diagonal terms of the interaction are included
in the unperturbed Hamiltonian, while the off-diagonal terms constitute the
perturbation that distorts the echo. We give the linear response solution for
this problem in a random matrix framework. While the ensemble average shows no
surprising behavior, we find that the typical ensemble member as represented by
the median displays a very slow fidelity decay known as ``freeze''. Numerical
calculations confirm this result and show, that the ground state even on
average displays the freeze. This may contribute to explanation of the
``unreasonable'' success of mean field theories.Comment: 9 pages, 5 figures (6 eps files), RevTex; v2: slight modifications
following referees' suggestion
Future NASA solar system exploration activities: A framework for international cooperation
The goals and approaches for planetary exploration as defined for the NASA Solar System Exploration Program are discussed. The evolution of the program since the formation of the Solar System Exploration Committee (SSEC) in 1980 is reviewed and the primary missions comprising the program are described
The inspiratory capacity/total lung capacity ratio as a predictor of survival in an emphysematous phenotype of chronic obstructive pulmonary disease.
BackgroundForced expiratory volume in 1 second (FEV1) grades severity of COPD and predicts survival. We hypothesize that the inspiratory capacity/total lung capacity (IC/TLC) ratio, a sensitive measure of static lung hyperinflation, may have a significant association with survival in an emphysematous phenotype of COPD.ObjectivesTo access the association between IC/TLC and survival in an emphysematous phenotype of COPD.MethodsWe performed a retrospective analysis of a large pulmonary function (PF) database with 39,050 entries, from April 1978 to October 2009. Emphysematous COPD was defined as reduced FEV1/forced vital capacity (FVC), increased TLC, and reduced diffusing capacity of the lungs for carbon monoxide (DLCO; beyond 95% confidence intervals [CIs]). We evaluated the association between survival in emphysematous COPD patients and the IC/TLC ratio evaluated both as dichotomous (≤25% vs >25%) and continuous predictors. Five hundred and ninety-six patients had reported death dates.ResultsUnivariate analysis revealed that IC/TLC ≤25% was a significant predictor of death (hazard ratio [HR]: 2.39, P<0.0001). Median survivals were respectively 4.3 (95% CI: 3.8-4.9) and 11.9 years (95% CI: 10.3-13.2). Multivariable analysis revealed age (HR: 1.19, 95% CI: 1.14-1.24), female sex (HR: 0.69, 95% CI: 0.60-0.83), and IC/TLC ≤25% (HR: 1.69, 95% CI: 1.34-2.13) were related to the risk of death. Univariate analysis showed that continuous IC/TLC was associated with death, with an HR of 1.66 (95% CI: 1.52-1.81) for a 10% decrease in IC/TLC.ConclusionAdjusting for age and sex, IC/TLC ≤25% is related to increased risk of death, and IC/TLC as a continuum, is a significant predictor of mortality in emphysematous COPD patients
Some Remarks about Variable Mass Systems
We comment about the general argument given to obtain the rocket equation as
it is exposed in standard textbooks. In our opinion, it can induce students to
a wrong answer when solving variable mass problems.Comment: 2 page
Preparations for Independence and Financial Security in Later Life: A Conceptual Framework and Application to Canada
In this paper, we develop a conceptual framework to describe an individual's preparations for later life. Situated in the life course perspective, this provides a framework that invites a more comprehensive and systematic study of preparations for later life. It describes a dynamic process that portrays the interplay between social structure and human agency. Through its consideration of collective preparations (the public protection programs offered by the state), individual preparations (financial and non- financial), and the interplay between the two, this framework provides fresh insight into the existing literature on retirement planning, the timing of retirement, savings, and consumption behaviour in later life. Moreover, the model may be used to structure research questions, to guide policy decision making and to point the direction for the design and content of future research studies. While the purpose of this paper is primarily the development of a conceptual model, we draw on empirical examples from the 1991 Survey of Aging and Independence (SAI) to illustrate some aspects of the model to Canada. We conclude by suggesting a number of research and questions that may be generated from the model.retirement planning; savings; SAI
Violation of the isotropic- approximation in overdoped La_{2-x}Sr_xCuO_4
Magnetotransport measurements on the overdoped cuprate La_{1.7}Sr_{0.3}CuO_4
are fitted using the Ong construction and band parameters inferred from
angle-resolved photoemission. Within a band picture, the low temperature Hall
data can only be fitted satisfactorily by invoking strong basal-plane
anisotropy in the mean-free-path . This violation of the isotropic-
approximation supports a picture of dominant small-angle elastic scattering in
cuprates due to out-of-plane substitutional disorder. We show that both band
anisotropy and anisotropy in the elastic scattering channel strongly
renormalize the Hall coefficient in overdoped La_{2-x}Sr_xCuO_4 over a wide
doping and temperature range.Comment: 4 pages, 4 figure
Task-Projected Hyperdimensional Computing for Multi-Task Learning
Brain-inspired Hyperdimensional (HD) computing is an emerging technique for
cognitive tasks in the field of low-power design. As a fast-learning and
energy-efficient computational paradigm, HD computing has shown great success
in many real-world applications. However, an HD model incrementally trained on
multiple tasks suffers from the negative impacts of catastrophic forgetting.
The model forgets the knowledge learned from previous tasks and only focuses on
the current one. To the best of our knowledge, no study has been conducted to
investigate the feasibility of applying multi-task learning to HD computing. In
this paper, we propose Task-Projected Hyperdimensional Computing (TP-HDC) to
make the HD model simultaneously support multiple tasks by exploiting the
redundant dimensionality in the hyperspace. To mitigate the interferences
between different tasks, we project each task into a separate subspace for
learning. Compared with the baseline method, our approach efficiently utilizes
the unused capacity in the hyperspace and shows a 12.8% improvement in averaged
accuracy with negligible memory overhead.Comment: To be published in 16th International Conference on Artificial
Intelligence Applications and Innovation
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