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Coal destruction is an energy-driven destabilization phenomenon. In order to investigate the effect of moisture on energy accumulation and dissipation during coal destruction, uniaxial compression tests on coal samples with different water content states were carried out, and the mechanical properties and impact energy index of coal were analyzed based on this. The results showed that the uniaxial compressive strength and elastic modulus of coal samples decreased significantly with the increase of water content; the proportion of the initial compression-density stage, plastic deformation damage stage and post-peak damage stage in the full stress-strain process of coal samples increased, and the proportion of linear elastic stage decreased; the accumulation deformation energy before the peak of coal samples decreased, the loss deformation energy after the peak increased, and the impact energy index decreased. The increase of water content changed the coal sample from splitting damage to shear damage, and the particle size of crumbling pieces became larger, the number of pieces decreased, and the damage sound weakened during the damage. The uniaxial compressive strength, impact energy index and impact energy velocity index of coal samples in water-saturated condition decreased by 35.32%, 86.07% and 99.63%, respectively, compared with those in dry condition, and the coal seam water injection process can effectively reduce the impact propensity of coal seam.

Deproteinized natural rubber （DPNR) latex was selected as the substrate for the modified rubber, the grafting copolymerization of acrylic acid （AA) monomer on DPNR chain was achieved and a type of hydrophilic AA modified DPNR copolymer （DPNR-g-PAA) was prepared based on the free ra-dical emulsion graft copolymerization of allyl of rubber macromolecule chain and vinyl monomer in the presence of re-dox initiating system, and the molecular structure, cross-sectional morphology, and water-swelling properties of DPNR-g-PAA were characte-rized by Fourier transform infrared spectroscopy, nuclear magnetic resonance hydrogen spectroscopy, scanning electron microscopy, and gravimetric method. The results showed that the water absorption rate of DPNR-g-PAA film as water-swellable rubber could reach 85.06%, and the surface moisture permeability of DPNR was significantly improved. Compared with the traditional process of physical blen-ding or solution grafting copolymerization, DPNR-g-PAA prepared by the free radical emulsion graft copolymerization had certain advantages.

Abstract Background Acute pulmonary embolism (APE) remains a diagnostic challenge due to a variable clinical presentation and the lack of a reliable screening tool. MicroRNAs (miRNAs) regulate gene expression in a wide range of pathophysiologic processes. Circulating miRNAs are emerging biomarkers in heart failure, type 2 diabetes and other disease states; however, using plasma miRNAs as biomarkers for the diagnosis of APE is still unknown. Methods Thirty-two APE patients, 32 healthy controls, and 22 non-APE patients (reported dyspnea, chest pain, or cough) were enrolled in this study. The TaqMan miRNA microarray was used to identify dysregulated miRNAs in the plasma of APE patients. The TaqMan-based miRNA quantitative real-time reverse transcription polymerase chain reactions were used to validate the dysregulated miRNAs. The receiver-operator characteristic (ROC) curve analysis was conducted to evaluate the diagnostic accuracy of the miRNA identified as the candidate biomarker. Results Plasma miRNA-134 (miR-134) level was significantly higher in the APE patients than in the healthy controls or non-APE patients. The ROC curve showed that plasma miR-134 was a specific diagnostic predictor of APE with an area under the curve of 0.833 (95% confidence interval, 0.737 to 0.929; P < 0.001). Conclusions Our findings indicated that plasma miR-134 could be an important biomarker for the diagnosis of APE. Because of this finding, large-scale investigations are urgently needed to pave the way from basic research to clinical utilization.

Background: Negative attitudes toward mental disorders are not only an interpersonal issue but also a concern of mental health care. Given that nursing students are future health care providers, it is pivotal to improve their attitudes toward individuals with mental disorders prior to their transition into clinical practice. However, research on nursing students' attitudes in relation to schizophrenia in Taiwan remains unexplored. Aim: The aim of this article is to examine the correlates of attitudes toward individuals with schizophrenia among Taiwanese undergraduate nursing students. Method: A descriptive, correlational, and cross-sectional study was adopted. Self-reported questionnaires were conducted with a convenience sample of 306 Taiwanese undergraduate nursing students. Descriptive statistics, independent t tests, one-way analysis of variance, Pearson's correlations, and a stepwise regression analysis were performed. Results: Nursing students expressed negative attitudes toward individuals with schizophrenia. Nursing students, who were female, had contact with individuals with mental disorders, and expressed greater empathy and personality traits held more favorable attitudes toward individuals with schizophrenia. The study found that empathy, personality traits, and academic year were the most crucial attributes contributing to attitudes of nursing students toward individuals with schizophrenia. Conclusion: Findings suggest that nursing education programs with empathy- and personality-tailored modules in mental health are pivotal to provide humanistic approaches with supportive attitudes regarding schizophrenia. [ABSTRACT FROM AUTHOR]

The aggregation of perylene diimide (PDI) and its derivatives strongly depends on the molecular structure and therefore has a great impact on the excited states. By regulating the molecular stacking such as monomer, dimer, J- and/or H-aggregate, the formation of different excited states is adjustable and controllable. In this study, we have synthesized two kinds of PDI derivatives: undecane-substituted PDI (PDI-1) and diisopropylphenyl-substituted PDI (PDI-2), and the films are fabricated with spin-coating method. By employing photoluminescence, time-resolved photoluminescence, and transient absorption spectroscopy, the excited-state dynamics of two PDI amorphous films have been investigated systematically. The result reveals that both films form excimers after photoexcitation mainly due to the stronger electronic coupling among molecule aggregate in the amorphous film. It should be noted that the excited state dynamics in PDI-2 shows a singlet fission like process, which is evidenced by the appearance of triplet state absorption. This study provides the dynamics of excited state in amorphous PDI films, and paves the way for better understanding and adjusting the excited state of amorphous PDI films. [ABSTRACT FROM AUTHOR]