5,349 research outputs found
Two-component electron fluid in underdoped high- cuprate superconductors
Evidence from NMR of a two-component spin system in cuprate high-
superconductors is shown to be paralleled by similar evidence from the
electronic entropy so that a two-component quasiparticle fluid is implicated.
We propose that this two-component scenario is restricted to the optimal and
underdoped regimes and arises from the upper and lower branches of the
reconstructed energy-momentum dispersion proposed by Yang, Rice and Zhang (YRZ)
to describe the pseudogap. We calculate the spin susceptibility within the YRZ
formalism and show that the doping and temperature dependence reproduces the
experimental data for the cuprates.Comment: 5 pages, 2 figures, accepted for publication in European Physics
Letter
Evidence for two electronic components in high-temperature superconductivity from NMR
A new analysis of 63Cu and 17O NMR shift data on La1.85Sr0.15CuO4 is reported
that supports earlier work arguing for a two-component description of this
material, but conflicts with the widely held view that the cuprates are a
one-component system. The data are analyzed in terms of two components A and B
with susceptibilities Chi(A), Chi(B), and Chi(AB)=Chi(BA) . We find that above
Tc, Chi(AB) and Chi(BB) are independent of temperature and obtain for the first
time the temperature dependence of all three susceptibilities above Tc as well
as the complete temperature dependence of Chi(AA)+Chi(AB) and of
Chi(AB)+Chi(BB) below Tc. The form of the results agrees with that recently
proposed by Barzykin and Pines.Comment: 14 pages, 4 figure
Tailoring the Statistical Experimental Design Process for LVC Experiments
The use of Live, Virtual and Constructive (LVC) Simulation environments are increasingly being examined for potential analytical use particularly in test and evaluation. The LVC simulation environments provide a mechanism for conducting joint mission testing and system of systems testing when scale and resource limitations prevent the accumulation of the necessary density and diversity of assets required for these complex and comprehensive tests. The statistical experimental design process is re-examined for potential application to LVC experiments and several additional considerations are identified to augment the experimental design process for use with LVC. This augmented statistical experimental design process is demonstrated by a case study involving a series of tests on an experimental data link for strike aircraft using LVC simulation for the test environment. The goal of these tests is to assess the usefulness of information being presented to aircrew members via different datalink capabilities. The statistical experimental design process is used to structure the experiment leading to the discovery of faulty assumptions and planning mistakes that could potentially wreck the results of the experiment. Lastly, an aggressive sequential experimentation strategy is presented for LVC experiments when test resources are limited. This strategy depends on a foldover algorithm that we developed for nearly orthogonal arrays to rescue LVC experiments when important factor effects are confounded
A Systematic Literature Review of the Current State of Knowledge Related to Interventions for Bereaved Parents
Aims:
The purpose of this systematic literature review is to describe the interventions for bereaved parents, evaluate intervention effectiveness through study methodology rigor, replicability, and theoretical foundations.
Methods:
We searched MEDLINE via PubMed (1966-2018), CINAHL (1937-present), PsycINFO (1887-present), and Embase (1947-present) using various search words and MeSH terms related to the study purpose. A blinded screening of title/abstract was performed, with conflicting inclusion decisions resolved through group discussions. Matrices for remaining articles were created and discussed among the team. The levels of evidence of the 9 records were rated from very low to high based on the Grading of Recommendations Assessment, Development, and Evaluation guidelines.
Results:
Our initial pool included 1025 articles. After the screening of titles/abstracts, 63 articles were retained for full-text reviews. Evaluated based on the inclusion/exclusion criteria, 9 records met the review criteria. Of the 9 records, 1 was graded as very low, 3 low, and 5 low to moderate. The interventions for bereaved parents varied from using single-model interventions such as expressive arts therapy and telephone support to multimodal interventions that combined resources (ie, peer support, resource packets, and health-care support). Only 1 study explicitly illustrated how its bereavement intervention was designed based on the proposed theoretical model.
Conclusions:
This review highlights the need for individualized, well-tested, and effective bereavement care interventions to support bereaved parents. In summary, the state of the science on interventions for bereaved parents is poor and much work needs to be done to effectively address the needs of bereaved parents, including both their physical and emotional health needs
Pointwise convergence of vector-valued Fourier series
We prove a vector-valued version of Carleson's theorem: Let Y=[X,H]_t be a
complex interpolation space between a UMD space X and a Hilbert space H. For
p\in(1,\infty) and f\in L^p(T;Y), the partial sums of the Fourier series of f
converge to f pointwise almost everywhere. Apparently, all known examples of
UMD spaces are of this intermediate form Y=[X,H]_t. In particular, we answer
affirmatively a question of Rubio de Francia on the pointwise convergence of
Fourier series of Schatten class valued functions.Comment: 26 page
Girls feeling good at school:School gender environment, internalization and awareness of socio-cultural attitudes associations with self-esteem in adolescent girls
Paper Session I-B - Modeling Methodology: The Use of Vehicle Control System Modeling for the International Space Station (ISS) Program
This paper presents a new control system software development approach entitled, RAPid Modeling and Analysis Philosophy (RAPMAP), and presents an example of the application of this approach on the International Space Station (ISS) program. RAPMAP embraces control system behavior modeling as an integral and ongoing part of the nominal development and integration process. Through a process called ‘Predictive-Verification,’ the RAPMAP approach ensures that development proceeds based on known and demonstrable performance and behavior throughout the development life cycle. The RAPMAP approach provides early identification of system integration issues and support for test and operational procedure development and training long before development products, which normally support these activities, are available. Section 1 of this paper introduces the concept of control system behavior modeling. Section 2 describes the RAPMAP approach and Section 3 provides a description of the the RAPMAP approach including a detailed description of its application on the ISS program. Section 4 summarizes the benefits of the RAPMAP approach
Developing and supporting quality nursery facilities and staff are necessary to meet global forest and landscape restoration needs
Seedlings are the foundation for many terrestrial ecosystems and are a critical consideration and investment for implementing global forest and landscape restoration programs. Global leaders have pledged to restore millions of hectares during the next decade, necessitating many millions of established plants. Although natural regeneration and direct seeding will likely meet a portion of that need, large quantities of high-quality, nursery-grown seedlings are also required. Insufficient plant quantities or poor-quality plants result in unsuccessful outplanting programs. Such failures have considerable economic and environmental consequences and will result in an inability to meet restoration goals. Nonetheless, the importance of restoration nurseries is often overlooked when making large-scale restoration commitments. Technology already exists to produce high-quality plants to meet a variety of goals. This technology cannot be applied, however, unless adequate resources and training are made available by overcoming political and socioeconomic barriers. In this article, we discuss the important role of nurseries to meet global restoration commitments and review three case studies where increased support to nursery programs resulted in improved restoration success
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