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The purpose of this study was to explore the longitudinal links between interpersonal competences and loneliness in Chinese college students. Participants were N = 623 undergraduate students (Mage = 20.34 years, SDage = 1.28 years; 42.5% males) from Shanghai, P.R. China, which were followed over two years, with half a year apart. The Interpersonal Competence Questionnaire (ICQ) and the University of California at Los Angeles (UCLA) Loneliness Scale were used to measure interpersonal competences and loneliness at each time point. Results indicated that as compared with the unidirectional model, the bidirectional model represented the best fit for the data. Within this model, after controlling for the stability of the variables, interpersonal competences directly contributed to later decreases in loneliness and loneliness directly led to decreases in interpersonal competences from Time 1 to Time 3, but not from Time 3 to Time 4. There is a bidirectional relationship between college students’ interpersonal competences and loneliness. Higher interpersonal competences can mitigate later loneliness, and higher loneliness can also weaken later interpersonal competences.

Additional file 2.

Additional file 1: Supplementary Table 1. Univariate analyses of ipsilateral CA parameters and clinical factors.

Explosion tests were performed underwater to study the blast resistance of water-backed sandwich panels. Effects on the structural response of face-sheet and core configurations, including face-sheet thickness, cell wall thickness of the honeycomb, core thickness and charge mass, were investigated by a large number of experiments. Quantitative results were obtained in the tests with corresponding sensors and further processing. Further results characterized the permanent deformation of sandwich panels. A failure mode map was adopted to identify the effect of design parameters on the structural failure mechanism at this blast magnitude. Finally, a comparison between sandwich panels and monolithic plates was performed. The comparative study provided further experimental evidence for the benefits of sandwich in water-backed configuration. Present study led to the apprehension of blast resistance of water-backed sandwich structure to underwater blast load, thereby developed useful guidelines for the design of blast-resistant structural systems.

Damage severity of sandwich panels to underwater explosion load depend not only on the shock factors, but also on the fluid behind the structure. Underwater explosion tests were performed on water-backed sandwich panels to examine the deformation and failure of such composite structure. The dynamic blast response of water-backed sandwich panel was investigated using the LS-DYNA software. An analytical three-stage model was developed for the deformation history of water-backed sandwich panel subjected to shock loading in water. Blast resistance of water-backed sandwich panel was compared with monolithic plate of equivalent areal mass and air-backed sandwich panel with the same configurations. Water-backed sandwich panel exhibited the best deformation/damage resistant capability. Compared with air-backed sandwich panel, core material exhibited greater volumetric strain when the sandwich structure wetted on both sides. Overpressure in the water behind structure was reduced to about 7% by using sandwich structure over monolithic plate of equivalent thickness. Present study led to the apprehension of dynamic response of water-backed sandwich structure to underwater blast load, thereby developed useful guidelines for the design of blast-resistant structural systems.

Additional file 1.

Experiments were conducted to study the underwater explosion performance of titanium hydride/RDX-based (TiH2/RDX) composite explosive. Cylinder charges with different TiH2 particle sizes and contents were prepared and tested. Explosion parameters like peak overpressure, impulse, shock energy, and bubble energy were analyzed. It was notable that underwater explosion performance of TiH2/RDX composite explosive was promoted by addition of small particle size TiH2 (D50=0.96 μm), in which case increasing TiH2 content also showed a favorable effect. The maximum increments of specific initial shock energy, bubble energy, and total energy were 10.5%, 6.4%, and 7.1% respectively. However, with bigger TiH2 particle sizes (D50=20.78 μm, D50=136.74 μm), the explosion parameters and the TiH2 content showed a negative relationship, which reveals that TiH2 particle size plays an important role in determining the reactivity of TiH2. Meanwhile, the interaction between TiH2 particle size and content was significant.

Due to a sedentary lifestyle, more and more people are becoming obese nowadays. In addition to health-related problems, obesity can also impair cognition and motor performance. Previous results have shown that obesity mainly affects cognition and motor behaviors through altering brain functions and musculoskeletal system, respectively. Many factors, such as insulin/leptin dysregulation and inflammation, mediate the effect of obesity and cognition and motor behaviors. Substantial evidence has suggested exercise to be an effective way to improve obesity and related cognitive and motor dysfunctions. This paper aims to discuss the association of obesity with cognition and motor behaviors and its underlying mechanisms. Following this, mechanisms of exercise to improve obesity-related dysfunctions are described. Finally, implications and future research direction are raised.

早大学位記番号:新7263