27,490 research outputs found

    Reflection high-energy electron diffraction patterns of CrSi_2 films on (111) silicon

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    Highly oriented films of the semiconducting transition metal silicide, CrSi2, were grown on (111) silicon substrates, with the matching crystallographic faces being CrSi_2(001)/Si(111). Reflection high‐energy electron diffraction (RHEED) yielded symmetric patterns of sharp streaks. The expected streak spacings for different incident RHEED beam directions were calculated from the reciprocal net of the CrSi_2(001) face and shown to match the observed spacings. The predominant azimuthal orientation of the films was thus determined to be CrSi_2〈210〉∥Si〈110〉. This highly desirable heteroepitaxial relationship may be described with a common unit mesh of 51 Å^2 and a mismatch of −0.3%. RHEED also revealed the presence of limited film regions of a competing azimuthal orientation, CrSi_2〈110〉∥Si〈110〉. A new common unit mesh for this competing orientation is suggested; it possesses an area of 612 Å^2 and a mismatch of −1.2%

    On the structure of subsets of an orderable group with some small doubling properties

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    The aim of this paper is to present a complete description of the structure of subsets S of an orderable group G satisfying |S^2| = 3|S|-2 and is non-abelian

    Equilibrium Configuration of Black Holes and the Inverse Scattering Method

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    The inverse scattering method is applied to the investigation of the equilibrium configuration of black holes. A study of the boundary problem corresponding to this configuration shows that any axially symmetric, stationary solution of the Einstein equations with disconnected event horizon must belong to the class of Belinskii-Zakharov solutions. Relationships between the angular momenta and angular velocities of black holes are derived.Comment: LaTeX, 14 pages, no figure

    Bottlenecks to vibrational energy flow in OCS: Structures and mechanisms

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    Finding the causes for the nonstatistical vibrational energy relaxation in the planar carbonyl sulfide (OCS) molecule is a longstanding problem in chemical physics: Not only is the relaxation incomplete long past the predicted statistical relaxation time, but it also consists of a sequence of abrupt transitions between long-lived regions of localized energy modes. We report on the phase space bottlenecks responsible for this slow and uneven vibrational energy flow in this Hamiltonian system with three degrees of freedom. They belong to a particular class of two-dimensional invariant tori which are organized around elliptic periodic orbits. We relate the trapping and transition mechanisms with the linear stability of these structures.Comment: 13 pages, 13 figure

    Algebras for parameterised monads

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    Parameterised monads have the same relationship to adjunctions with parameters as monads do to adjunctions. In this paper, we investigate algebras for parameterised monads. We identify the Eilenberg-Moore category of algebras for parameterised monads and prove a generalisation of Beck’s theorem characterising this category. We demonstrate an application of this theory to the semantics of type and effect systems

    Clustered bottlenecks in mRNA translation and protein synthesis

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    We construct an algorithm that generates large, band-diagonal transition matrices for a totally asymmetric exclusion process (TASEP) with local hopping rate inhomogeneities. The matrices are diagonalized numerically to find steady-state currents of TASEPs with local variations in hopping rate. The results are then used to investigate clustering of slow codons along mRNA. Ribosome density profiles near neighboring clusters of slow codons interact, enhancing suppression of ribosome throughput when such bottlenecks are closely spaced. Increasing the slow codon cluster size, beyond 34\approx 3-4, does not significantly reduce ribosome current. Our results are verified by extensive Monte-Carlo simulations and provide a biologically-motivated explanation for the experimentally-observed clustering of low-usage codons

    Is traditional Chinese medicine recommended in Western medicine clinicalpractice guidelines in China? A systematic analysis.

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    Background: Evidence-based medicine promotes and relies on the use of evidence in developing clinical practice guidelines (CPGs). The Chinese healthcare system includes both traditional Chinese medicine (TCM) and Western medicine, which are expected to be equally reflected in Chinese CPGs. Objective: To evaluate the inclusion of TCM-related information in Western medicine CPGs developed in China and the adoption of high level evidence. Methods: All CPGs were identified from the China Guideline Clearinghouse (CGC), which is the main Chinese organisation maintaining the guidelines issued by the Ministry of Health of China, the Chinese Medical Association and the Chinese Medical Doctors' Association. TCM-related contents were extracted from all the CPGs identified. Extracted information comprised the institution issuing the guideline, date of issue, disease, recommendations relating to TCM, evidence level of the recommended content and references supporting the recommendations. Results: A total of 604 CPGs were identified, only a small number of which (74/604; 12%) recommended TCM therapy and only five guidelines (7%) had applied evidence grading. The 74 CPGs involved 13 disease systems according to the International Classification of Diseases 10th edition. TCM was mainly recommended in the treatment part of the guidelines (73/74, 99%), and more than half of the recommendations (43/74, 58%) were related to Chinese herbal medicine (single herbs or herbal treatment based on syndrome differentiation). Conclusions: Few Chinese Western medicine CPGs recommend TCM therapies and very few provide evidence grading for the TCM recommendation. We suggest that future guideline development should be based on systematic searches for evidence to support CPG recommendations and involve a multidisciplinary approach including TCM expertise

    Pengaruh Budaya Organisasi, Motivasi Intrinsik, dan Motivasi Ekstrinsik terhadap Prestasi Kerja Karyawan pada PT. Bringin Srikandi Finance

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    From The Research Findings Showed That 1) Organizational Culture Has A Positive And Significant Impact On Employee Performance. 2) Intrinsic Motivation Has A Positive And Significant Effect On Employee Performance. 3) Extrinsic Motivation Has A Positive And Significant Effect On Employee Performance. 4) The Result Of Coefficient Of Determination Of Employee Work Performance After Influenced By Organizational Culture Variable, Intrinsic Motivation, Extrinsic Motivation Is 90,9%, And The Rest 9,1% Determined Other Unchecked Factors Such As Organizational Climate, Job Satisfaction, And Communication From Leader -Subordinate. The Conclusion Of The Research Shows That Organizational Culture Variables, Intrinsic Motivation, Extrinsic Motivation Partially Have Significant Effect On Employee Performance At Pt Bringin Srikandi Finance. From The Results Of The Study Note That Extrinsic Motivation Variable Has A Very Strong And Significant Influence On Employee Performance At Pt Bringin Srikandi Finance With Beta Coefficient Acquisition Of 0,51

    On the structure of the new electromagnetic conservation laws

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    New electromagnetic conservation laws have recently been proposed: in the absence of electromagnetic currents, the trace of the Chevreton superenergy tensor, HabH_{ab} is divergence-free in four-dimensional (a) Einstein spacetimes for test fields, (b) Einstein-Maxwell spacetimes. Subsequently it has been pointed out, in analogy with flat spaces, that for Einstein spacetimes the trace of the Chevreton superenergy tensor HabH_{ab} can be rearranged in the form of a generalised wave operator L\square_L acting on the energy momentum tensor TabT_{ab} of the test fields, i.e., Hab=LTab/2H_{ab}=\square_LT_{ab}/2. In this letter we show, for Einstein-Maxwell spacetimes in the full non-linear theory, that, although, the trace of the Chevreton superenergy tensor HabH_{ab} can again be rearranged in the form of a generalised wave operator G\square_G acting on the electromagnetic energy momentum tensor, in this case the result is also crucially dependent on Einstein's equations; hence we argue that the divergence-free property of the tensor Hab=GTab/2H_{ab}=\square_GT_{ab}/2 has significant independent content beyond that of the divergence-free property of TabT_{ab}
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