Strong Analytic Controllability for Hydrogen Control Systems

The realization and representation of so(4,2) associated with the hydrogen atom Hamiltonian are derived. By choosing operators from the realization of so(4,2) as interacting Hamiltonians, a hydrogen atom control system is constructed, and it is proved that this control system is strongly analytically controllable based on a time-dependent strong analytic controllability theorem.Comment: 6 pages; corrected typo; added equations in section III for representation states of so(4,2). accepted by CDC 200

Parental Autonomy Support and Psychological Well-Being in Tibetan and Han Emerging Adults: A Serial Multiple Mediation Model

A growing body of research has explored well-being in diverse cultural contexts, and indicates that the definition and perception of well-being vary according to cultural context. Little is known, however, about whether intercultural differences in China (i.e., Tibetan and Han) lead to different perceptions of well-being and how social contexts and personal characteristics are associated with well-being in Tibetan and Han emerging adults. Using a self-determination framework, the current study examines the relationship between parental autonomy support (PAS) and psychological well-being (PWB) in Tibetan and Han emerging adults in China. Guided by implicit theory and self-regulatory theory, we propose a serial multiple mediation model of growth mindset and grit in the association between PAS and PWB. Propensity score matching was used to balance the two ethnic groups in terms of age, gender, socioeconomic status (SES), with a ratio of one to two. Finally, 59 Tibetan (71.2% girls) and 118 Han (69.5% girls) emerging adults aged from 18 to 25 years were included in the current study, and completed an online questionnaire survey. Findings suggest that (a) Tibetan emerging adults perceived higher levels of PWB than their peers from the Han ethnic group; (b) a serial multiple mediation model for the association between PAS and PWB was supported in Han emerging adults; (c) the indirect effects between PAS and PWB varied between Tibetan and Han emerging adults. Our findings suggest that PAS and grit contribute to PWB of emerging adults in both cultural contexts, whereas growth mindset may be beneficial for Han emerging adults only

Linking classmate autonomy support with prosocial behavior in Chinese left-behind adolescents: The moderating role of self-esteem and grit

Framed in a positive youth development framework, the current study examines the association of classmate autonomy support with prosocial behavior in Chinese left-behind adolescents (i.e., adolescents who remain immobile in original regions when one or both of their parents have migrated to find work). Moreover, this study investigates whether left-behind adolescents' individual differences in self-esteem and grit moderated this association. To address these research aims, we examined these associations across two independent samples of left-behind adolescents [Study 1 (exploratory): N = 333, Mage = 13.16, SD = 1.67; 48.3% girls; Study 2 (confirmatory): N = 246, Mage = 15.78, SD = 1.50; 53.6% girls] recruited from different regions of mainland China. Study 1 showed that classmate autonomy support was positively correlated with prosocial behavior; self-esteem and grit moderated this association: for adolescents with low self-esteem, high grit was an important protective factor, fostering the positive association between classmate autonomy support and prosocial behavior. Furthermore, Study 2 replicated the results of Study 1 but also exhibited that, for adolescents with high self-esteem, high grit significantly buffered against the negative effect of low classmate autonomy support on adolescents' prosocial behavior. Taken together, the current study suggests that classmate autonomy support plays a crucial role in facilitating left-behind youths' prosocial behavior, and this association is differentiated by adolescents' self-esteem and grit

Directly mapping whispering gallery modes in a microsphere through modal coupling and directional emission

We fabricate slightly deformed fused-silica microspheres in which whispering gallery modes possess remarkably directional escape emission from the microsphere boundary. With efficient free-space excitation and collection, the lateral spatial distribution of whispering gallery modes with different azimuthal mode numbers, m, is directly observed through modal coupling and directional emission. Excellent agreement with theory is obtained

Achieving high power factor and output power density in p-type half-Heuslers Nb

Improvements in thermoelectric material performance over the past two decades have largely been based on decreasing the phonon thermal conductivity. Enhancing the power factor has been less successful in comparison. In this work, a peak power factor of ∼106 μW⋅cm⁻¹⋅K⁻² is achieved by increasing the hot pressing temperature up to 1,373 K in the p-type half-Heusler Nb[subscript 0.95]Ti[subscript 0.05]FeSb. The high power factor subsequently yields a record output power density of ∼22 W⋅cm⁻² based on a single-leg device operating at between 293 K and 868 K. Such a high-output power density can be beneficial for large-scale power generation applications.United States. Department of Energy (DE-SC0001299

Analytic Controllability of Time-Dependent Quantum Control Systems

The question of controllability is investigated for a quantum control system in which the Hamiltonian operator components carry explicit time dependence which is not under the control of an external agent. We consider the general situation in which the state moves in an infinite-dimensional Hilbert space, a drift term is present, and the operators driving the state evolution may be unbounded. However, considerations are restricted by the assumption that there exists an analytic domain, dense in the state space, on which solutions of the controlled Schrodinger equation may be expressed globally in exponential form. The issue of controllability then naturally focuses on the ability to steer the quantum state on a finite-dimensional submanifold of the unit sphere in Hilbert space -- and thus on analytic controllability. A relatively straightforward strategy allows the extension of Lie-algebraic conditions for strong analytic controllability derived earlier for the simpler, time-independent system in which the drift Hamiltonian and the interaction Hamiltonia have no intrinsic time dependence. Enlarging the state space by one dimension corresponding to the time variable, we construct an augmented control system that can be treated as time-independent. Methods developed by Kunita can then be implemented to establish controllability conditions for the one-dimension-reduced system defined by the original time-dependent Schrodinger control problem. The applicability of the resulting theorem is illustrated with selected examples.Comment: 13 page

Original Article Benefit of a 360-degree horizontal turn following premedication with simethicone on image quality during gastroendoscopy: a randomized controlled trial

Abstract: Objectives: To investigate whether a 360-degree horizontal turn after oral premedication with simethicone improves the mucosal visibility during gastroendoscopic examination, and to determine the proper time to turn over the patient. Methods: This study involved 993 patients scheduled for gastroendoscopy. Just before gastroendoscopy，after oral premedication with simethicone, patients were randomly assigned to three groups：in Group A, patients waited for 20 min before gastroendoscopy; in Group B, patients were separately waited for 5/10/15/20 min and were then turned 360 degrees just before gastroendoscopy; in Group C, patients were immediately turned 360 degrees and then separately waited for 5/10/15/20 min before examination. The sum of the gastric mucosal visibility scores (MVS) was calculated after the examination. The MVS and proportion of images with higher visibility scores for the mucosal surface. Lower scores indicate better visibility of the mucosal surface. Results: In Groups B and Groups C, when waiting time more than 10 min had lower mean total MVS than Group A. The MVS of four subgroups of Group B were not different from those of Group C. Conclusion: Oral premedication with simethicone and immediately make a body posture change (turning over 360 degrees) then waiting for 10min can increase the image quality during gastroendoscopy and effectively decrease the premedication time