1,420 research outputs found

    Validation of the Japanese Version of the Burnout Assessment Tool

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    The current study aimed to validate the Japanese version of the Burnout Assessment Tool (BAT-J), a new burnout measure. We conducted an Internet survey to confirm the validity and reliability of the BAT-J, using registered monitors from a Japanese survey company. The first-wave survey was conducted in May 2018, with 1,032 monitors. Of these, 498 participated in the second-wave survey in June 2018 to confirm 1-month test-retest reliability. We examined the factorial validity of the BAT-J core symptoms (BAT-JC) and BAT-J secondary symptoms (BAT-JS), as well as their reliability (internal consistency and test-retest reliability) and construct validity. Factorial validity was examined using confirmatory factor analyses and exploratory structural equation modeling bifactor analyses. Convergent and discriminant validity were examined using multitrait-multimethod frameworks well as the average variance explained. Exploratory structural equation modeling bifactor solutions for the BAT-JC, BAT-JS, and BAT-J demonstrated the best fit to the data. They also indicated that the general factor accounted for over two-thirds of the common variance explained. Internal consistency and test-retest reliability were confirmed. Convergent and internal discriminant validity of the BAT-JC were confirmed vis-vis burnout, as assessed with the Maslach Burnout Inventory - General Survey. Moreover, external discriminant validity of the BAT-J was demonstrated for work engagement and workaholism. Finally, both BAT scales showed significant positive relationships with job demands and turnover intention. All validity results were in line with the job demands-resources model. The results of the current study provide the first evidence for the BAT-J's reliability and factorial and construct validity.Peer reviewe

    The time-dependent Schrödinger equation: the need for the Hamiltonian to be self-adjoint

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    We present some simple arguments to show that quantum mechanics operators are required to be self-adjoint. We emphasize that the very definition of a self-adjoint operator includes the prescription of a certain domain of the operator. We then use these concepts to revisit the solutions of the time-dependent Schroedinger equation of some well-known simple problems - the infinite square well, the finite square well, and the harmonic oscillator. We show that these elementary illustrations can be enriched by using more general boundary conditions, which are still compatible with self-adjointness. In particular, we show that a puzzling problem associated with the Hydrogen atom in one dimension can be clarified by applying the correct requirements of self-adjointness. We then come to Stone\'s theorem, which is the main topic of this paper, and which is shown to relate the usual definitions of a self-adjoint operator to the possibility of constructing well-defined solutions of the time-dependent Schrödinger equation.Conselho Nacional de Desenvolvimento Cientí fico e Tecnológico (CNPq)Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP

    E2F site activates transcription in fission yeast Schizosaccharomyces pombe and binds to a 30-kDa transcription factor

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    The mammalian transcription factor E2F binds to several cellular proteins including Rb, p107, cyclin A, cyclin E, and p33cdk2 protein kinase in a stage-specific manner during cell cycle. Its recognition sequence, TTTCGCGC, is present in two of the human adenovirus early promoters and in several promoters of cellular genes whose products are implicated in the control of cell proliferation. These observations suggest that E2F may play an important role in cell-cycle regulation and prompted us to ask whether E2F-like activities are present in yeast. We found that the E2F motif can function as an activating sequence in Schizosaccharomyces pombe when cloned upstream of a reporter gene. Consistent with this, the expression of adenovirus E2 promoter in S. pombe was dependent on both E2F motifs of this promoter. A protein, spE2F, that binds to the E2F site was partially purified from S. pombe using DNA-affinity chromatography. The binding specificity of this protein was compared to that of human E2F using a number of mutant E2F sites as competitors. These studies showed that spE2F recognizes a sequence closely related to the E2F site. Ultraviolet cross-linking and Southwestern blot studies indicated that the molecular size of spE2F is 30 kDa. Previous studies have shown that a cis-acting element, ACGCGTNA, also called MluI cell cycle box, or MCB, is critical for the regulated expression of cell cycle related genes both in fission and budding yeast. In S. pombe, the cdc10 gene product binds to this element and controls the cell cycle related genes. Electrophoretic mobility shift assays and molecular size determination studies indicated that spE2F is different from that encoded by cdc10. Thus, our studies suggest that spE2F is a novel transcription factor. We discuss these results in light of recent observations about the periodically expressed genes involved in the cell cycle progression in yeast

    Relativistic confinement of neutral fermions with a trigonometric tangent potential

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    The problem of neutral fermions subject to a pseudoscalar potential is investigated. Apart from the solutions for E=±mc2E=\pm mc^{2}, the problem is mapped into the Sturm-Liouville equation. The case of a singular trigonometric tangent potential (tanγx\sim \mathrm{tan} \gamma x) is exactly solved and the complete set of solutions is discussed in some detail. It is revealed that this intrinsically relativistic and true confining potential is able to localize fermions into a region of space arbitrarily small without the menace of particle-antiparticle production.Comment: 12 page

    The Dirac Oscillator. A relativistic version of the Jaynes--Cummings model

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    The dynamics of wave packets in a relativistic Dirac oscillator is compared to that of the Jaynes-Cummings model. The strong spin-orbit coupling of the Dirac oscillator produces the entanglement of the spin with the orbital motion similar to what is observed in the model of quantum optics. The collapses and revivals of the spin which result extend to a relativistic theory our previous findings on nonrelativistic oscillator where they were known under the name of `spin-orbit pendulum'. There are important relativistic effects (lack of periodicity, zitterbewegung, negative energy states). Many of them disappear after a Foldy-Wouthuysen transformation.Comment: LaTeX2e, uses IOP style files (included), 14 pages, 9 separate postscript figure

    Magnetoresistivity in a Tilted Magnetic Field in p-Si/SiGe/Si Heterostructures with an Anisotropic g-Factor: Part II

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    The magnetoresistance components ρxx\rho_{xx} and ρxy\rho_{xy} were measured in two p-Si/SiGe/Si quantum wells that have an anisotropic g-factor in a tilted magnetic field as a function of temperature, field and tilt angle. Activation energy measurements demonstrate the existence of a ferromagnetic-paramagnetic (F-P) transition for a sample with a hole density of pp=2×1011\times10^{11}\,cm2^{-2}. This transition is due to crossing of the 0\uparrow and 1\downarrow Landau levels. However, in another sample, with pp=7.2×1010\times10^{10}\,cm2^{-2}, the 0\uparrow and 1\downarrow Landau levels coincide for angles Θ\Theta=0-70o^{\text{o}}. Only for Θ\Theta > 70o^{\text{o}} do the levels start to diverge which, in turn, results in the energy gap opening.Comment: 5 pages, 6 figure

    Controlling a resonant transmission across the δ\delta'-potential: the inverse problem

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    Recently, the non-zero transmission of a quantum particle through the one-dimensional singular potential given in the form of the derivative of Dirac's delta function, λδ(x)\lambda \delta'(x) , with λR\lambda \in \R, being a potential strength constant, has been discussed by several authors. The transmission occurs at certain discrete values of λ\lambda forming a resonance set λnn=1{\lambda_n}_{n=1}^\infty. For λλnn=1\lambda \notin {\lambda_n}_{n=1}^\infty this potential has been shown to be a perfectly reflecting wall. However, this resonant transmission takes place only in the case when the regularization of the distribution δ(x)\delta'(x) is constructed in a specific way. Otherwise, the δ\delta'-potential is fully non-transparent. Moreover, when the transmission is non-zero, the structure of a resonant set depends on a regularizing sequence Δε(x)\Delta'_\varepsilon(x) that tends to δ(x)\delta'(x) in the sense of distributions as ε0\varepsilon \to 0. Therefore, from a practical point of view, it would be interesting to have an inverse solution, i.e. for a given λˉR\bar{\lambda} \in \R to construct such a regularizing sequence Δε(x)\Delta'_\varepsilon(x) that the δ\delta'-potential at this value is transparent. If such a procedure is possible, then this value λˉ\bar{\lambda} has to belong to a corresponding resonance set. The present paper is devoted to solving this problem and, as a result, the family of regularizing sequences is constructed by tuning adjustable parameters in the equations that provide a resonance transmission across the δ\delta'-potential.Comment: 21 pages, 4 figures. Corrections to the published version added; http://iopscience.iop.org/1751-8121/44/37/37530

    Different eGFR decline thresholds and renal effects of cnagliflozin: data from the CANVAS program

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    BACKGROUND: Traditionally, clinical trials evaluating effects of a new therapy with creatinine-based renal end points use doubling of serum creatinine (equivalent to a 57% eGFR reduction), requiring large sample sizes. METHODS: To assess whether eGFR declines <57% could detect canagliflozin's effects on renal outcomes, we conducted a post hoc study comparing effects of canagliflozin versus placebo on composite renal outcomes using sustained 57%, 50%, 40%, or 30% eGFR reductions in conjunction with ESKD and renal death. Because canagliflozin causes an acute reversible hemodynamic decline in eGFR, we made estimates using all eGFR values as well as estimates that excluded early measures of eGFR influenced by the acute hemodynamic effect. RESULTS: Among the 10,142 participants, 93 (0.9%), 161 (1.6%), 352 (3.5%), and 800 (7.9%) participants recorded renal outcomes on the basis of 57%, 50%, 40%, or 30% eGFR reduction, respectively, during a mean follow-up of 188 weeks. Compared with a 57% eGFR reduction (risk ratio [RR], 0.51; 95% confidence interval [95% CI], 0.34 to 0.77), the effect sizes were progressively attenuated when using 50% (RR, 0.61; 95% CI, 0.45 to 0.83), 40% (RR, 0.70; 95% CI, 0.57 to 0.86), or 30% (RR, 0.81; 95% CI, 0.71 to 0.93) eGFR reductions. In analyses that controlled for the acute hemodynamic fall in eGFR, effect sizes were comparable, regardless of whether a 57%, 50%, 40%, or 30% eGFR reduction was used. Estimated sample sizes for studies on the basis of lesser eGFR reductions were much reduced by controlling for this early hemodynamic effect. CONCLUSIONS: Declines in eGFR <57% may provide robust estimates of canagliflozin's effects on renal outcomes if the analysis controls for the drug's acute hemodynamic effect. CLINICAL TRIAL REGISTRY NAME AND REGISTRATION NUMBER: CANagliflozin cardioVascular Assessment Study (CANVAS), NCT01032629 and CANVAS-R, NCT01989754

    Optical Kerr-effect in fiber-optic Brillouin ring laser gyroscopes

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    The optical Kerr effect in a reciprocal fiber-optic Brillouin ring laser gyroscope is investigated. It is found that the Kerr effect, as the major error source of the rotation rate measurement in this gyroscope, causes a bias of beat frequency with nonlinear dependence on rotation rate. A differential Stokes power of 1 mW inside the ring resonator is measured to produce a beat frequency bias of 69 Hz, which agrees well with the theoretical expectatio

    Isolation and characterization of a novel 2-sec-butylphenol-degrading bacterium Pseudomonas sp. strain MS-1

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    A novel bacterium capable of utilizing 2-sec-butylphenol as the sole carbon and energy source, Pseudomonas sp. strain MS-1, was isolated from freshwater sediment. Within 30 h, strain MS-1 completely degraded 1.5 mM 2-sec-butylphenol in basal salt medium, with concomitant cell growth. A pathway for the metabolism of 2-sec-butylphenol by strain MS-1 was proposed on the basis of the identification of 3 internal metabolites—3-sec-butylcatechol, 2-hydroxy-6-oxo-7-methylnona-2,4-dienoic acid, and 2-methylbutyric acid—by gas chromatography-mass spectrometry analysis. Strain MS-1 degraded 2-sec-butylphenol through 3-sec-butylcatechol along a meta-cleavage pathway. Degradation experiments with various alkylphenols showed that the degradability of alkylphenols by strain MS-1 depended strongly on the position (ortho ≫ meta = para) of the alkyl substitute, and that strain MS-1 could degrade 2-alkylphenols with various sized and branched alkyl chain (o-cresol, 2-ethylphenol, 2-n-propylphenol, 2-isopropylphenol, 2-sec-butylphenol, and 2-tert-butylphenol), as well as a dialkylphenol (namely, 6-tert-butyl-m-cresol)
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