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This study used the Latent Dirichlet Allocation (LDA) topic model to analyze pre-service teachers' views on the nature of science (NOS). This approach can be used to automate the classification of documents, and at the same time, the researcher does not need to deduce with a NOS framework prior to evaluation. Participants were 155 pre-service teachers studying at the Shandong Normal University in China. To gather our data, we used an open questionnaire, namely, the Views of Nature of Science Questionnaire-Form C (VNOS-C). LDA topic modeling was used to classify the document, which was divided into 12 topics. By comparing the LDA topic modeling results with the theoretical framework behind the VNOS-C questionnaire, we categorized these 12 topics into eight descriptive aspects of the NOS: The Empirical Nature of Scientific Knowledge, Observation, Inference, and Theoretical Entities in Science, Scientific Theories and Laws, The Theory-Laden Nature of Scientific Knowledge, The Social and Cultural Embeddedness of Scientific Knowledge, The Myth of The Scientific Method, The Tentative Nature of Scientific Knowledge, and The Nature of Scientific Theory. The results show that pre-service teachers usually hold naive or mixed views of the NOS. In addition, each aspect of NOS is not independent of each other but interrelated and influencing each other. In the future, more consideration can be given to the relationship between each aspect of NOS.

G protein-coupled receptors (GPCRs), as the largest family of receptors in the human body, are involved in the pathological mechanisms of many diseases. Heterotrimeric G proteins represent the main molecular switch and receive cell surface signals from activated GPCRs. Growing evidence suggests that Gα12 subfamily (Gα12/13)-mediated signaling plays a crucial role in cellular function and various pathological processes. The current research on the physiological and pathological function of Gα12/13 is constantly expanding, Changes in the expression levels of Gα12/13 have been found in a wide range of human diseases. However, the mechanistic research on Gα12/13 is scattered. This review briefly describes the structural sequences of the Gα12/13 isoforms and introduces the coupling of GPCRs and non-GPCRs to Gα12/13. The effects of Gα12/13 on RhoA and other signaling pathways and their roles in cell proliferation, migration, and immune cell function, are discussed. Finally, we focus on the pathological impacts of Gα12/13 in cancer, inflammation, metabolic diseases, fibrotic diseases, and circulatory disorders are brought to focus.

Obesity has now surpassed malnutrition and infectious diseases as the most significant contributor to health problems worldwide. In particular, obesity is associated with several metabolic disorders, including hyperlipidemia, hepatic steatosis, and subfertility. Genipin (GNP), the aglycone of geniposide, is isolated from the extract of the traditional Chinese medicine Gardenia jasminoides Ellis and has been used in traditional oriental medicine against several inflammation-driven diseases. However, the effect and molecular mechanism of GNP on obesity-associated dyslipidemia and sperm dysfunction still need to be explored. In this study, we detect the effects of GNP on hyperlipidemia, hepatic lipid accumulation and sperm function using a high-fat diet (HFD)-induced obese mouse model. We find that obese mice treated with GNP show an improvement in body weight, serum triglyceride levels, serum hormone levels, serum inflammatory cytokines, hepatic steatosis and sperm function. At the molecular level, HFD/GNP diversely regulates the expression of miR-132 in a tissue-specific manner. miR-132 further targets and regulates the expression of SREBP-1c in liver cells, as well as the expressions of SREBP-1c and StAR in Leydig cells in the testis, thus modifying lipogenesis and steroidogenesis, respectively. Collectively, our data demonstrate that GNP shows a broad effect on the improvement of HFD-induced metabolic disorder and sperm dysfunction in male mice by tissue-specific regulation of miR-132. Our findings reveal the function GNP in ameliorating hepatic lipid metabolism and sperm function and suggest that this compound is a versatile drug to treat metabolic disorders.

3-Nitro-1,2,4-triazole-5-one (NTO) has received wide attention and has applications owing to its excellent detonation performance and low sensitivity. A new crystal form of NTO was prepared via the solvent evaporation method and named γ-NTO. Its crystal properties were studied through single-crystal X-ray diffraction, and the results indicated that the unit cell of γ-NTO belongs to the monoclinic space group Pc, with eight molecules in the single unit cell. The density of this crystal is calculated to be 1.907 g cm−3, which is higher than that of β-NTO and similar to that of α-NTO. The crystal morphology was calculated to be a polygonal shape with a symmetrical growth pattern using the reactive force field. Based on the analysis of reactive molecular dynamics, the thermal decomposition mechanism of different crystal forms of NTO was elucidated, and the results showed that γ-NTO demonstrates higher gas production, providing a successful way to enhance detonation performance. The results of IR and differential thermal analysis (DTA) support the above conclusions. [ABSTRACT FROM AUTHOR]

Stress, especially chronic stress, is a high risk factor of many physical and mental health problems. This work acquired 702 days of full-day ambulatory electrocardiogram (ECG) and Tri-axial acceleration (T-ACC) data from 104 healthy college students and realized chronic stress recognition through signal processing, statistical test and machine learning. We divided the 24 hours of a day into 153 time slots, and calculated 30 features from ECG and T-ACC data in each time slot. Statistical test of the above 30 features of the subjects with chronic stress and no chronic stress labels showed that chronic stress altered the autonomic nervous control of the heart not only in the daily activity time but also in the rest time at night, leading to smaller heart rate variability, faster heart rate and less complexity of the heartbeat rhythm. More specifically, the parasympathetic nervous activity at night was weakened by chronic stress. We expressed the ECG and T-ACC data of a day as a 30 × 153 data matrix, applied a four-layer fully connected neural network to classify the data of 702 days with chronic stress and no chronic stress labels, and obtained 88.17% chronic stress detection accuracy in the leave-one-subject-out cross test. [ABSTRACT FROM AUTHOR]