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In order to solve the problem of low detection efficiency and long working time in the traditional video surveillance system for abnormal behavior detection and identification methods. A multimodal abnormal behavior detection and identification method based on video surveillance is proposed and applied to an online video classroom concentration evaluation task for college students in English. The model works by capturing abnormal behaviors and facial expressions and building a joint network that fuses abnormal behaviors and facial expressions. By testing on two open-source datasets and self-built classroom real-time datasets, the results verify that the model in this paper has better recognition performance compared to current mainstream models while maintaining real-time performance. The model proposed in this paper provides a new way of thinking about building smart classrooms. [ABSTRACT FROM AUTHOR]

To improve the solubility and bioactivity of chitosan, a new class of carboxymethyl chitosan derivatives possessing sulfonium salts was successfully designed and synthesized, including Methyl sulfide carboxymethyl chitosan (MCMCS), Ethyl sulfide carboxymethyl chitosan (ECMCS), Propyl sulfide carboxymethyl chitosan (PCMCS), and Butyl sulfide carboxymethyl chitosan (BCMCS). To determine the structure of the new class of the derivatives, methods of the Fourier transform infrared spectroscopy (FT-IR), 1H nuclear magnetic resonance spectrometer (1H NMR), and 13C nuclear magnetic resonance spectrometer (13C NMR) were used. Moreover, the antioxidant activity of the derivatives for three types of free radicals, i.e., hydroxyl radical, superoxide radical, and 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical was evaluated in vitro. In addition, the L929 cells were adopted to test the cytotoxicity of chitosan and its derivatives by CCK-8 assay. The class of the carboxymethyl chitosan derivatives showed a strong scavenging ability against the three free radicals at 1.6 mg/mL, with scavenging rate of over 70% and some up to 100%. At this high rate, the overall cell viability in the toxicity test reached more than 80%, indicating that the synthetic derivative had a little cytotoxicity. The results show that the introduction of carboxymethyl group to chitosan increased the water-solubility of chitosan, and the combination of sulfonate ions with different chain lengths further enhanced the antioxidant activity of chitosan. Therefore, the sulfonium-containing carboxymethyl chitosan derivatives had excellent bioactivity with good application prospects in food, biomedicine, and medical fields. [ABSTRACT FROM AUTHOR]

Emerging technologies, like industrial robotics and so forth, are profoundly changing the ways of working and producing. However, their impact on the environment is debated. This research examines whether and how intelligent production represented by industrial robot applications impacts Chinese manufacturing firms’ carbon emission behaviors. We further estimate the forward (with upstream suppliers) and backward (with downstream buyers) vertical linkages effects. The findings reveal that intelligent production has significantly reduced carbon emission intensity. Carbon reduction is achieved by reducing energy intensity, improving firm production, and enhancing innovation. The effects are more pronounced on small and medium-sized firms, firms with lower energy consumption levels, and firms with higher intelligence levels. In addition, the forward vertical linkages have significantly unfavorable effects on reducing carbon emission intensity, while the backward vertical linkage effects are not significant. Our work helps to understand the environmental impact of intelligent production and its spillover effects along the supply chain. [ABSTRACT FROM AUTHOR]

Previous studies have examined the associations of meteorological factors with blood pressure; however, these associations have not fully elucidated, especially lacking of evidence from cohort study, little information about the associations of cold pressor sensitivity with blood pressure and its fluctuation. The objective of this study was to investigate the outdoor and indoor temperature, barometric pressure, humidity, and cold pressor sensitivity with blood pressure and its fluctuation. Forty-eight healthy subjects were recruited, and response of blood pressure to cold exposure was measured with cold pressor test (CPT). Then, all the subjects were followed up, and blood pressure was measured every half a month in a period of consecutive 12 months. Multiple panel analysis with random-effects generalized least squares (GLS) regression was used to analyze the effect of the outdoor and indoor temperature, barometric pressure, humidity, and response to cold pressor exposure on blood pressure. Outdoor and indoor temperature and humidity were found to be independently associated with blood pressure (all the P values < 0.05). The response to cold exposure positively associated with blood pressure and its fluctuation (P < 0.05). The subjects with higher cold pressor sensitivity had about 4.7 mmHg higher maximum difference of SBP in 1 year than the subjects with lower sensitivity. Outdoor and indoor temperature, humidity, and response to cold exposure are associated with blood pressure and its fluctuation. These findings provided extending evidence on blood pressure management in clinic and preventive practice. [ABSTRACT FROM AUTHOR]

Patients with alcohol use disorder may develop acute ethanol withdrawal syndrome (EWS). Previous studies showed that an epigenetic modification of the N-methyl-d-aspartate (NMDA) receptor, especially NMDA receptor 2B subunit (NR2B), was involved in the pathological process of EWS. However, the relationship between the epigenetic regulation of the NR2B gene in the rat hippocampus region and EWS were inconsistent. The purpose of this study was to explore the role of the histone H3K9 acetylation of the NR2B gene in the rat hippocampus region in EWS. A rat model of chronic ethanol exposure was established. EWS score and the behavioral changes were recorded at different time points. The NR2B expression levels and the histone H3K9 acetylation level in the NR2B gene promoter region were measured using qRT-PCR, Western blot, immunofluorescence, and chromatin immunoprecipitation, respectively. Finally, the relationship between the epigenetic modification of histone H3K9 acetylation of NR2B gene promoter and EWS were examined. Our ultimate results showed that the EWS score was increased at 2 h, peaked at 6 h after withdrawal of ethanol, and reduced to the level parallel to the normal control group at day 3 after ethanol withdrawal. The NR2B mRNA expression and protein levels showed similar patterns. Further correlation analyses indicted that both histone H3K9 acetylation in NR2B gene promoter and the expression levels of NR2B were positively associated with EWS. Our results suggest that chronic ethanol exposure may result in epigenetic modification of histone H3K9 acetylation in NR2B gene promoter in rat hippocampus, and the expression levels of NR2B were found to be positively correlated with ethanol withdrawal syndrome. [ABSTRACT FROM AUTHOR]

Objective: To produce a recombinant spermatozoa antigen peptide using the E. coli: PhoA system on a protein chip for screening anti-sperm antibodies (ASA). Results: The purity of the recombinant spermatozoa antigen exceeded 95% after two-step purification, as assessed using SDS-PAGE and HPLC. The diagnostic performance of a protein chip coated with the recombinant antigen peptide was evaluated by examining ASA in 51 infertile patients in comparison with a commercial ELISA kit. The area under the receiver operating characteristic curve (AUC) was 0.944, which indicated that the protein chip coated with recombinant spermatozoa antigen peptide was consistent with ELISA for ASA detection. Conclusion: A recombinant spermatozoa antigen was expressed in the E. coli PhoA secretory expression system and its potential application for clinical ASA detection was validated. [ABSTRACT FROM AUTHOR]

The objective of this study is to detect the p66shc mRNA and protein expression of the peripheral blood monocytes (PBMs) in coronary heart disease patients (CHD) and controls, to evaluate the correlation between the expression of p66shc mRNA in the PBMs and endothelium-dependent vasodilatation. This study included 78 coronary angiography-documented CHD patients (CHD group) and 38 non-CHD controls (control group). The p66shc mRNA and protein levels were determined by quantitative real-time PCR and western blotting. The flow-mediated dilatation (FMD, endothelium-dependent), nitroglycerine-induced dilatation (NID, endothelium-independent) and carotid intimal medial thickness (CIMT) were detected using high-resolution ultrasound. The p66shc mRNA and the protein expression levels in the PBMs were significantly higher in the CHD group compared with the control group ( p = 0.007 and 0.001). The FMD ( p < 0.001) and NID ( p = 0.013) were significantly lower and the CIMT ( p = 0.007) was significantly thicker in the CHD patients than in the controls. In the univariate analysis, the expression of the p66shc mRNA in the PBMs was significantly positively correlated with the serum LDL-C and homocysteine levels and the CIMT and was inversely correlated with the FMD and the NID (all p < 0.001). In the multiple linear regression analysis, the FMD ( p < 0.001), LDL-C ( p = 0.002) and homocysteine levels ( p = 0.002) remained independently correlated with the p66shc mRNA expression. These findings highlight a pivotal role for the expression of p66shc in CHD and endothelial dysfunction, which might represent a molecular target to prevent endothelial dysfunction-related disease. [ABSTRACT FROM AUTHOR]

Background: Galangin (3,5,7-trihydroxyflavone) is present in high concentrations in herbal medicine such as Alpinia officinarum Hance. Galangin shows multifaceted in vitro and in vivo biological activities. The number and position of hydroxyl groups in this molecule play an important role in these biological activities. However, these hydroxyl groups undergo glucuronidation and sulfation in in vitro assay system. However, the systemic exposure to galangin after dosing in animals and/or humans remains largely unknown. Thus it is not clear whether the galangin exists in the body at concentrations high enough for the biological effects. Furthermore, the metabolite identification and the corresponding plasma pharmacokinetics need to be characterized. Results: Two LC-MS/MS methods were developed and validated and successfully applied to analyze the parent drug molecules and aglycones liberated from plasma samples via β-glucuronidase hydrolysis. Our major findings were as follows: (1) The routes of administration showed significant influences on the systemic exposure of galangin and its metabolites. (2) Galangin was preferentially glucuronidated after p.o. dosing but sulfated after i.v. medication. (3) Kaempferol conjugates were detected demonstrating that oxidation reaction occurred; however, both glucuronidation and sulfation were more efficient. (4) Oral bioavailability of free parent galangin was very low. Conclusions: Systemic exposure to galangin and its metabolites was different in rat plasma between oral and intravenous administration. Further research is needed to characterize the structures of galangin conjugates and to evaluate the biological activities of these metabolites. [ABSTRACT FROM AUTHOR]

Absorption dyes are widely used in traditional cytology and pathology clinical practice, while fluorophores and nanoparticles are more often used in biologic research. Optical projection tomographic microscopy (OPTM) is a platform technology that can image the same specimen in multiple modes in 3D, providing morphologic and molecular information concurrently and in exact co-registration. The depth-of-field of a high numerical aperture objective is extended by scanning the focal plane through the sample to generate an optical projection image. Samples of cells or tissue are brought into the OPTM instrument through a microcapillary tube filled with optical index-matching gel. Multiple optical projection images are taken from different perspectives by rotating the tube. Computed tomography (CT) algorithms are applied to these optical projection images to reconstruct 3D structure of the sample. Image segmentation and analysis based on these 3D images provide quantitative biosignatures for cancer diagnosis that represents a clear improvement over conventional 2D image analysis. In this article, we introduce the OPTM platform, optical Cell-CT, and Tissue-CT instruments, and some applications using these OPTM instruments. [ABSTRACT FROM AUTHOR]

The optimum shape of a two-dimensional undulatory plate in its motion in fluid flow is analyzed and the physical parameters (the thrust and the power) are calculated by the boundary element method. With the commonly used Lagrange multiplier method, only a saddle point of the optimum solution can be obtained, but not the solution itself due to the singularity of the problem. To eliminate the singularity, a method is proposed by adding an amplitude constraint. The new method is a generalization of that proposed by Wu, and it can be applied to more complex cases. The optimum shape of the linearly varying amplitude motion is studied in detail. It is shown that both the maximum and the minimum solutions exist when the frequency is higher than a critical value. For a high frequency, the maximum efficient motion with a large amplitude at the leading edge and a small amplitude at the trailing edge induces a large leading edge suction force. As the frequency decreases, the leading edge suction force decreases to a minimum and then increases. For high wavenumbers, there exists an optimum frequency with the maximum efficiency. High efficiency holds over a large range of frequency. The optimum efficiency increases as the wavenumber increases. The increase of the wavenumber can also reduce the leading edge suction force. The optimization method can also be applied to a quadratically varying amplitude motion. It is found that the optimum efficiency is larger than that for the linearly varying amplitude motion. However, the additional efficiency is relatively small, especially as the original efficiency is already high enough. [ABSTRACT FROM AUTHOR]

Matrix metalloproteinases (MMPs) are zinc- and calcium-dependent enzymes that cleave molecules of the extracellular matrix, and thus are able to open the blood-brain-barrier and affect myelin. Their inhibitors (TIMPs) are important candidates for the therapy of demyelinating diseases. To establish an immunohistochemical profile of MMP and TIMP expression in plaque variants in dogs with spontaneous demyelinating distemper encephalitis, paraffin-embedded cerebella were studied employing the avidin-biotin-peroxidase complex method with a panel of nine polyclonal (anti-MMP-1, -3, -7, -9, -12, -13, -14, -TIMP-1, and -2) and two monoclonal antibodies (anti-latent MMP-2, and -MMP-11). All MMPs and TIMPs were prominently up-regulated in acute and subacute non-inflammatory lesions, and double-labeling techniques showed that they were mainly expressed by astrocytes and brain macrophages/microglia. In subacute inflammatory and chronic plaques, a moderate to strong decrease of MMP and TIMP expression compared to acute lesions was observed. In these phases MMP-11, -12, and -13 were still moderately present. In addition to astro- and microglia, invading perivascular mononuclear cells were positive for MMPs and TIMPs. In summary, there seems to be a phase-dependent expression of MMPs and TIMPs in demyelinating canine distemper encephalitis, and an MMP-TIMP imbalance might account for the lesion progression in this disease. [ABSTRACT FROM AUTHOR]