Fast Fusion Clustering via Double Random Projection.

In unsupervised learning, clustering is a common starting point for data processing. The convex or concave fusion clustering method is a novel approach that is more stable and accurate than traditional methods such as k-means and hierarchical clustering. However, the optimization algorithm used with this method can be slowed down significantly by the complexity of the fusion penalty, which increases the computational burden. This paper introduces a random projection ADMM algorithm based on the Bernoulli distribution and develops a double random projection ADMM method for high-dimensional fusion clustering. These new approaches significantly outperform the classical ADMM algorithm due to their ability to significantly increase computational speed by reducing complexity and improving clustering accuracy by using multiple random projections under a new evaluation criterion. We also demonstrate the convergence of our new algorithm and test its performance on both simulated and real data examples.

Simulation of sports training recognition system based on internet of things video behavior analysis.

The video behavior analysis of the Internet of Things is the apparent characteristics and continuous state of the two-dimensional human body in the time dimension. The patterns representing human behavior can be divided into states based on human body structure, forms based on common features and forms based on temporal features, local spaces, and behaviors based on deep learning. Applying IoT video behavior analysis to sports training will have a huge impact. Physical training is the process of training people to improve their physical fitness, increase courage and endurance, and acquire practical skills. It is the basis of various training courses and an important way to improve human physical fitness. The motion recognition system is a DTW pattern matching method, which uses a finite state to describe the spatial characteristics of the angle between the joint points. This method can accurately meet the low-delay requirements of the motion recognition of each frame and the standard motion. It can match and eliminate the influence of individual differences on motion recognition. At the same time, it can also effectively expand the pattern matching method to recognize newly filled motions, and it is a powerful composite general motion recognition system.

Heterogeneous logistic regression for estimation of subgroup effects on hypertension.

Personalized medicine has gained much attention in the past decades, and identifying the effects of factors is essential for personalized preventions and treatments. Hypertension is a major modifiable risk factor for cardiovascular disease and is influenced by complex factors. In order to decrease the incidence of hypertension effectively, the subjects should be divided into subgroups according to their characteristics. In this study, we proposed to use a heterogeneous logistic regression combined with a concave fusion penalty to analyze the population-based survey data, including common influencing factors of hypertension. The analytic steps include: (1) identifying the most important predictor; (2) estimating subgroup-based heterogeneous effects. In the present context of primary hypertension data, the modeling results showed that the calculated prediction accuracy under our method was greater than 99%, while zero under the classical logistic regression. The findings could provide a practical guide for further individualized measures implementation.

What motivates individual public service motivation and cooperation at the initial stage of the COVID-19 outbreak: A cross-sectional survey.

OBJECTIVES: This study assesses the status of public service motivation and explains it's the positive association with public cooperation during the initial stage of the COVID-19 crisis. Moreover, potential causes of Chinese citizens' public service motivation have been explored. METHODS: A cross-sectional survey of 30 provinces in China was conducted using an online questionnaire. The study was conducted in February 2020 during the initial stage of the COVID-19 pandemic. Socio-demographic factors, public service motivation, public satisfaction, public confidence, and public cooperation were assessed using questionnaires. Hierarchical multiple regression was used to identify clusters of interrelationships among public service motivation, public satisfaction, public confidence, and public cooperation among Chinese citizens. RESULTS: We found that participants' public satisfaction with COVID-19-related public services had a positive association with public confidence (B = 0.456, p < 0.001) and public service motivation (B = 0.177, p < 0.001). Moreover, public confidence regarding anti-COVID-19 measures had a positive influence on public service motivation (B = 0.308, p < 0.001) while mediating the relationship between public satisfaction and public service motivation. Public service motivation were positively associated with public cooperation with anti-COVID-19 measures during the initial stage of the COVID-19 pandemic. CONCLUSION: A considerably high level of public service motivation among Chinese citizens appeared during the initial stage of the COVID-19 pandemic, resulting in an increase in public cooperation. Moreover, the findings prove that a high degree of satisfaction with the government's initiatives regarding anti-COVID-19 measures encouraged greater personal public service motivation in respondents by increasing confidence in governmental responses and performance.

Does abusive supervision lead nurses to suffer from workplace violence? A cross-sectional study.

AIM: This study aimed to (1) assess the current status of Chinese nurses' exposure to workplace violence; (2) identify the cluster of interrelationships between abusive supervision, anxiety and depression symptoms, work ability, and workplace violence in nursing settings; and (3) clarify the functional mechanism among these variables. METHODS: A cross-sectional survey was conducted online from September to October 2020 in China. A total of 1,221 valid questionnaires were collected across 100 cities in 31 provinces. RESULTS: Approximately 67.57% of participants experienced workplace violence in the past one year, in the types of verbal violence (59.71%), made difficulties (43.16%), mobbing behaviour (26.70%), smear reputation (22.52%), physical violence (11.30%), intimidating behaviour (10.16%) and sexual harassment (4.10%), respectively. Moreover, nurses' exposure to workplace violence was significantly and positively influenced by the perceptions of abusive supervision (ß = 0.209, p < .01) and the symptoms of anxiety and depression (ß = 0.328, p < .01). Anxious and depressive symptoms partly mediated the association between abusive supervision and workplace violence, which were significantly moderated by work ability (ß = -0.021, p < .05). CONCLUSIONS: Our study assesses the prevalence of the seven types of workplace violence against Chinese nurses. Majority of nurses have experienced different types of workplace violence. Nurses who are abused by their supervisor are more likely to develop poor psychological health than those who are not. Moreover, nurses' positive association of abusive supervision with workplace violence is more notable among nurses with lower work ability. IMPLICATIONS OF NURSING MANAGEMENT: 'No abusive supervision, no workplace violence'. A harmonious nursing environment needs to be provided to minimize exposure to workplace violence and mental health threats towards nursing staff, which is a key point for hospital administrators and health policymakers. Essential work ability should be developed to reduce the damage of the abusive supervision and workplace violence against nurses.

Assembling of Sulfur Quantum Dots in Fission of Sublimed Sulfur.

A novel kind of quantum dots, sulfur quantum dots (S dots), is synthesized by simply treating sublimated sulfur powders with alkali using polyethylene glycol-400 as passivation agents. The synthesized S dots exhibit excellent aqueous dispersibility, eminent photostability and temperature dependent photoluminescence (PL). An "assemble-fission" mechanism is proposed for the S dots formation in which "assembling" and "fission" are involved and contest each other. The ultimate morphologies of the S dots are dependent on the balance of the two forces. Guided by the assemble-fission mechanism, weakening the assembling effect is beneficial for obtaining monodisperse S dots, which can be achieved by pretreating of sulfur powder with nitric acid. PL wavelength of the S dots has been successfully tuned between green and blue light (from 550 to 440 nm) by simply controlling reaction time. A satisfactory quantum yield of 3.8% is obtained. Significant electrochemiluminescence of the S dots is observed in an annihilation reaction. Chemiluminescence from the S dots has been observed by direct oxidation. Taking advantage of unique and inherent antimicrobial activity of the sulfur particles, it is believed that this new emerging luminescent nanomaterial is highly promising in the development of new types of optoelectronic devices and tracer for live cells, in vivo imaging and diagnostics.

Two new 2-(2-Hydroxy-2-phenylethyl)chromens from agarwood originating from Aquilaria crassna.

Two new 2-(2-hydroxy-2-phenylethyl)chromones (1‒2), along with three known 2-(2-phenylethyl)chromones (3‒5), were isolated from the agarwood originating from Aquilaria crassna Pierre ex Lecomte. Their structures were determined by the spectroscopic methods including 1D and 2D NMR analysis and comparison with reported data in the literature. All the compounds were isolated from agarwood of A. crassna for the first time. Compounds 1 and 2 exhibited inhibitory activity against acetylcholinesterase (AChE) with 17.4 ± 0.6 and 15.8 ± 0.7%, respectively, at a concentration of 50 µg/ml. Besides, Compound 3 expressed antibacterial activities against Ralstonia solanacearum with diameter of the inhibition zone of 6.80 ± 0.08 mm at a concentration of 10 mg/ml.

Emission Spectrometry for the Detection of Methane Based on Gas Ionization Discharge Microplasma at Room Temperature.

A microplasma-generating device was developed by using needle-plate electrode discharge with the incorporation a Pt/carbon nanotube (CNT) nanocomposite-decorated FTO electrode. When an alternating current voltage of 1.32 kV and a low power consumption of 13 W in nitrogen (N2) carrier gas are applied, the system can be applied to detect methane at room temperature. The main characteristic lines were assigned to CH, C2 and Hα during the discharge process of CH4 at room temperature.The emission intensity of C2 at 516 nm is linear with the concentration of CH4 from 0.5% to 4.0% (φ), and the detection limit (S/N=3) is 0.19% (φ). The emission intensity of Hα at 656 nm is linear with the concentration of CH4 from 0.1% to 3.0%(φ)with the detection limit (S/N=3) is 0.03% (φ). The relative standard deviation (RSD) is less than 2% from 11 repetitive analyses using 3.2% CH4. The Pt/CNT nanocomposite-modified FTO electrode exhibited enhanced sensing performance with precise, repeatability and linear correlation compared with that of the pure MWNT/FTO electrode and bare FTO electrode. When CH4 were discharged in air, the emission spectra of CH4 was different from that in N2. It was found that C2 peak was disappeared and the Hα intensity was also liner to the concentration of CH4 in the range of 0.5%～4%. The established system exhibited advantages with small size, simple fabrication and operation at room temperature compared to other detection system.

Synthesis of phenanthridine derivatives via cascade annulation of diaryliodonium salts and nitriles.

A cascade coupling reaction toward a variety of phenanthridine derivatives has been developed. This cascade transformation proceeds via the copper-catalyzed coupling reaction of diaryliodonium salts and nitriles, and undergoes cyclization into the phenanthridine core.

Mild gold-catalyzed three-component dehydrogenative coupling of terminal alkynes to amines and indole-2-carboxaldehyde.

A mild gold-catalyzed three-component dehydrogenative coupling of terminal alkynes to amines and indole-2-carboxaldehyde has been developed, which provides a practical synthetic strategy for the synthesis of indole derivatives.

Chemical and structural changes in preserved white egg during pickled by vacuum technology.

The aim of the present study was to investigate the chemical and structural changes in preserved white egg during pickled by vacuum technology. In order to evaluate the changes of preserved egg white during its salted period, sulfhydryl group, disulfide bond contents, and surface hydrophobicity were measured. Fourier transformation infrared spectroscopy and circular dichroism analysis were performed by considering changes of the secondary structural elements, the protein components of egg white was also studied in more detail by electrophoresis. Results showed that the sulfhydryl group and surface hydrophobicity were increased with increasing salting time, whereas a decrease in the disulfide bond contents was observed. Regarding the secondary structure analysis, a decrease in α-helices and ß-turns were accompanied by increases in ß-sheets and random coils, which indicating a decrease in non-random structure while ever increasing of unordered structure. Electrophoresis shows no significant differences in protein patterns among fresh egg white and samples salting for up to 4 days. Disappearance of most protein was at the 5th day. Single band of ovalbumin can be readily observed from the 6th day to the ripening period finished. Our findings reveal that high pH could induce duck egg white protein aggregation when salting eggs in strong alkaline solution for a long time.

Electrostatically Assisted Construction Modified MXene-IL-Based Nanofluids for Photothermal Conversion.

Solar energy, as renewable energy, has paid extensive attention for solar thermal utilization due to its unique characteristics such as rich resources, easy access, clean, and pollution-free. Among them, solar thermal utilization is the most extensive one. Nanofluid-based direct absorption solar collectors (DASCs), as an important alternative method, can further improve the solar thermal efficiency. Notably, the stability of photothermal conversion materials and flowing media is critical to the performance of DASC. Herein, we first proposed novel Ti3C2Tx-IL-based nanofluids by the electrostatic interaction, which consists of functional Ti3C2Tx modified with PDA and PEI as a photothermal conversion material and ionic liquid with low viscosity as the flow medium. Ti3C2Tx-IL-based nanofluids exhibit excellent cycle stability, wide spectrum, and efficient solar energy absorption performance. Besides, Ti3C2Tx-IL-based nanofluids maintain liquid state in a range of -80 to 200 °C, and its viscosity was as low as 0.3 Pa·s at 0 °C. Moreover, the equilibrium temperature of Ti3C2Tx@PDA-IL at a very low mass fraction of 0.04% reached 73.9 °C under 1 Sun, indicating an excellent photothermal conversion performance. Furthermore, the application of nanofluids in photosensitive inks has been preliminarily explored, which is expected to play a role in the fields of injectable biomedical materials and photo/electric double-generation thermal and hydrophobic anti ice coatings.

Synergistic Regulation of the Microstructure for Multifunctional Graphene Aerogels by a Dual Template Method.

The performance of graphene aerogels (GAs) is based on the microstructure. However, GAs face a challenge of simultaneously controlling the size and alignment of pores strategically. Herein, we initially proposed a simple strategy to construct GAs with an adjustable structure based on the emulsion and ice dual template methods. Specifically, GAs with a honeycomb structure prepared by conventional freezing (CGAs) exhibited a high specific surface of 176 m2/g, superelasticity with a compressive strain of 95%, isotropic compression and thermal insulation performances, as well as an excellent absorption capacity of 150-550 g/g. Instead, the GAs with a bamboo-like network frozen by unidirectional freezing (UGAs) showed anisotropy in compression and thermal insulation behavior. Furthermore, UGAs exhibited incredible special stress (7.9 kPa cm3/mg) along the axial direction twice than that of the radial direction. Meanwhile, the apparent temperature of UGAs was only 45.6 °C when placed on a 120 °C hot stage along the radial direction. Remarkably, the properties of CGAs and UGAs were significantly improved with the adjustment of the microstructure.

Fabrication of Durable, Chemically Stable, Self-Healing Superhydrophobic Fabrics Utilizing Gellable Fluorinated Block Copolymer for Multifunctional Applications.

Limited durability and complex materials restrict the application of superhydrophobic fabrics in daily life. In this work, gellable fluorinated block copolymer poly(dodecafluoroheptyl methacrylate)-block-poly(3-(triethoxysilyl)propyl methacrylate) (PDFMA-b-PTEPM) was used to fabricate adhesive-free superhydrophobic poly(ethylene terephthalate) (PET) fabrics via a simple dip-coating technology and sol-gel reaction. The growth of silica nanoparticles builds up a rough hierarchical structure and provides sol-gel reaction sites of PTEPM segments. The grafting of block copolymer significantly reduced the surface free energy of the fabrics, resulting in an excellent superhydrophobicity with a water contact angle of 160.2°. Benefiting from extensive chemical bond grafting and cross-linking of the PTEPM segment, the fabric exhibits excellent durability in mechanical abrasion, chemical treatment, and washing. The coating has withstood 50 sandpaper abrasion cycles and 400 soft friction cycles and can maintain superhydrophobic properties in various solvents, freezing and a wide pH range. These superhydrophobic fabrics with a long life span possess self-cleaning, anti-icing, oil-water separation, and self-healing capabilities. The multifunctional fabrics developed in this study are durable and easy to produce, possessing the potential for applications in industry and daily life.

Core-Shell ZIF67@ZIF8 Modified with Phytic Acid as an Effective Flame Retardant for Improving the Fire Safety of Epoxy Resins.

Despite many important industrial applications, epoxy resin (EP) suffers from high flammability and toxicity emission, extremely hampering their applications. To circumvent the problem, core-shell structured ZIF67@ZIF8 is successfully synthesized and further functionalized with phytic acid (PA) to obtain PA-ZIF67@ZIF8 hybrids. Then, it is used as an efficient flame retardant to reduce the fire risk of EP. The fire test results show a significant reduction in heat and smoke production. Compared with EP, incorporating 5.0 wt % PA-ZIF67@ZIF8 into EP, the peak heat release rate, total heat release, and peak carbon monoxide production are dramatically reduced by 42.2, 33.0, and 41.5%, respectively. Moreover, the EP/PA-ZIF67@ZIF8 composites achieve the UL-94 V-0 rating and the limiting oxygen index increases by 29.3%. These superior fire safety properties are mainly attributed to the excellent dispersion and the catalytic effect of metal oxide and phosphorus-containing compounds. This work provides an efficient strategy for preparing a promising ZIF-based flame retardant for enhancing flame retardancy and smoke toxicity suppression of EP.

What are the Bad Habits and Behaviors of Inconsiderate Doctors in Chinese Inhabitants' Mind? A Cross-Sectional Study.

Purpose: This study aims to 1) investigate inhabitants' perceptions of doctors' inconsiderate behaviors during diagnosis and treatment, 2) explore the factors influencing inhabitants' attitudes toward doctors' professional reputation, and 3) examine the status of doctors' inconsiderate behaviors and inhabitants' attitudes and behaviors toward these doctors in China. Patients and Methods: A cross-sectional online survey was conducted with 2050 participants from over 30 Chinese cities, from March to June 2018. In total, 1598 valid questionnaires were obtained (with an effective response rate of 77.95%). Data were analyzed using descriptive statistics, exploratory factor analysis, and logistic linear regression analysis. Results: We developed a questionnaire comprising of 15 items regarding doctors' inconsiderate behaviors based on inhabitants' perspectives (Cronbach's alpha was 0.944). Additionally, we identified the factors that influence the attitudes of inhabitants regarding doctors' professional reputation, such as frequency of medical consultations, medical expenses, education catalog, and type of medical insurance. A majority of the participants highly valued Chinese doctors' professional reputation (87.55%), and trusted them (86.29%). However, about 60.27% of the participants reported a pessimistic-like judgment on the current doctor-patient relationship (DPR) in China. Participants believed that Chinese doctors received a high income (20.47%), maintained a high social status (23.46%), and had a heavy workload (59.95%). Furthermore, about 54.88% of participants reported that they would not engage in aggressive behaviors against doctors during a dispute. Lastly, about 26.66% of participants reported that they would act rationally when they were dissatisfied with their doctors. Conclusion: Impassive emotions and improper actions of doctors toward patients jointly contributed to the disrepute of Chinese doctors. Although DPR was becoming tense, Chinese inhabitants held a positive evaluation of doctors' professional reputation. While an improvement in the economic situation and reputation of doctors enhanced the DPR, there remains an urgent need to improve the working environment in regard to future Chinese health reforms.

Job demands and resources and their relationship with satisfaction and thriving at work in a sample of Chinese doctors: a cross-sectional study.

OBJECTIVES: The current study aimed to evaluate the status quo of perceived job demands and resources respectively among Chinese doctors, to examine the mediating role of work-family conflicts in the relationship between perceived job demands and various indicators of well-being, and to test the mediating role of psychological attachment in the relationship between perceived job resources and thriving at work among Chinese doctors. DESIGN: A cross-sectional online survey study. SETTING: Online questionnaires were administered across 30 provinces. PARTICIPANTS: A total of 2617 doctors provided sufficiently complete responses to be used in the study. RESULTS: Perceived job demands (M=3.843, SD=0.791) of participants were positively associated with work-family conflicts (B=0.454, p<0.001) and negatively associated with job satisfaction (B=-0.065, p<0.001) and life satisfaction (B=-0.261, p<0.001). Work-family conflicts partially mediated the relationship between job demands and life satisfaction and fully mediated the relationship between job demands and job satisfaction. Perceived job resources (M=2.474, SD=0.740) among Chinese doctors were positively associated with psychological attachment (B=0.988, p<0.001) and thriving at work (B=0.582, p<0.001). Furthermore, psychological attachment partially mediated the relationship between perceived job resources and thriving at work. CONCLUSION: Doctors in China with high-level job demands tended to exhibit increased work-family conflicts, which in turn threatened their job and life satisfaction. On the contrary, doctors with greater job resources were more likely to thrive at work by increasing their degree of psychological attachment. The current study suggested that Chinese health policymakers and hospital administrators should provide a work environment with a dynamic equilibrium between doctors' job demands and resources.

Transforming Metal-Organic Frameworks into Porous Liquids via a Covalent Linkage Strategy for CO2 Capture.

Porous liquids (PLs), an emerging kind of liquid materials with permanent porosity, have attracted increasing attention in gas capture. However, directly turning metal-organic frameworks (MOFs) into PLs via a covalent linkage surface engineering strategy has not been reported. Additionally, challenges including reducing the cost and simplifying the preparation process are daunting. Herein, we proposed a general method to transform Universitetet i Oslo (UiO)-66-OH MOFs into PLs by surface engineering with organosilane (OS) and oligomer species via covalent bonding linkage. The oligomer species endow UiO-66-OH with superior fluidity at room temperature. Meanwhile, the resulting PLs showed great potential in both CO2 adsorption and CO2/N2 selective separation. The residual porosity of PLs was verified by diverse characterizations and molecular simulations. Besides, CO2 selective capture sites were determined by grand canonical Monte Carlo (GCMC) simulation. Furthermore, the universality of the covalent linkage surface engineering strategy was confirmed using different classes of oligomer species and another MOF (ZIF-8-bearing amino groups). Notably, this strategy can be extended to construct other PLs by taking advantages of the rich library of oligomer species, thus making PLs promising candidates for further applications in energy and environment-related fields, such as gas capture, separation, and catalysis.

Contribution of Character Strengths to Psychology Stress, Sleep Quality, and Subjective Health Status in a Sample of Chinese Nurses.

Objectives: The main objectives of this study were to describe the current state of character strengths (CSs) of nurses; explain how they affect stress, sleep quality, and subjective health status; and reveal the mediating role of stress for the subject matter on the association between CSs, sleep quality, and subjective health status. Methods: A cross-sectional online survey was conducted from September to October 2020 in China. A multistage stratified sampling method was used, and 1,221 valid questionnaires across 100 cities in 31 provinces were collected. Results: For the participants in this survey, the three dimensions of CSs ranging from high to low were caring (4.20 ± 0.640), self-control (3.53 ± 0.763), and inquisitiveness (3.37 ± 0.787). There was difference in CSs scores across age (F = 8.171, P < 0.01), professional categories (F = 5.545, P < 0.01), and job tenure (F = 9.470, P < 0.01). The results showed that CSs significantly affected the psychological stress (ß = -0.365, P< 0.01), sleep quality (ß = 0.312, P< 0.01), and subjective health (ß = 0.398, P< 0.01) of nurses. Moreover, psychological stress partially mediated the association between CSs and both types of health outcomes. Conclusion: In China, the CSs of nurses are at high levels. We find that nurses with high-level CSs are likely to experience less psychological stress and exhibit healthy psycho-physiological responses, which contribute to positive health outcomes. Finally, our study argues that strength-based interventions of positive psychology in hospitals should be provided to minimize threats to the physical and psychological health of health professionals, which is a beneficial choice for future hospital reforms in the domain of occupational health management.

Demographic Factors and Job Characteristics Associated With Burnout in Chinese Female Nurses During Controlled COVID-19 Period: A Cross-Sectional Study.

Background: To investigate the prevalence of burnout syndrome among Chinese female nurses during the controlled coronavirus disease 2019 (COVID-19) period and explore its associated socio-demographic factors and job characteristics. Methods: With the multistage, stratified sampling method, a cross-sectional online survey was conducted from September to October 2020 in China. The survey tool included revised Maslach Burnout Inventory (MBI) with 15 items, socio-demographic and job characteristics. Univariate logistic regression analysis and multivariate factor logistic regression analysis were used to identify the risk factors for burnout of female nurses. Results: During controlled COVID-19 period in China, the overall prevalence of burnout symptoms among Chinese female nurses was 60.2% with a breakdown in severity as follows: 451 (39.8 %) mild, 163 (14.4%) moderate, and 68 (6.0%) severe burnout. Little variance was reported for burnout symptoms according to job tenure (Waldχ2 = 14.828, P < 0.05,odds ratio [OR] <1), monthly salary income (Waldχ2 = 12.460, P < 0.05, OR <1), and night shift (Waldχ2 = 3.821, P < 0.05, OR > 1). Conclusion: Burnout symptoms among Chinese female nurses were prevalent and associated with job tenure, monthly salary income, and night shift. Female nurses who were with shorter job tenure, worked at night shifts, and had lower monthly salaries tended to exhibit increasing high-level burnout than their counterparts. This study serves as an implication for administrators and policy-makers to improve the work conditions of nurses for promoting overall healthcare service quality.