Evaluation and associated factors of public health emergency management among medical college students in a city in Southwest China: a cross-sectional study.

BACKGROUND: Colleges and universities face an increased risk of public health emergencies. Among them, medical colleges and universities deserve more attention as they serve as the play a fundamental role in providing public health emergency services and in cultivating medical professionals. Effectively managing infectious disease prevention and control, as well as responding to public health emergencies in medical colleges and universities, is of great importance for enhancing the capacity of social emergency governance and improving the completeness of the public health system. This study aims to understand the management of public health emergencies in medical colleges in a city in southwest China, explore the factors associated with medical college students' evaluations, and provide recommendations for emergency management mechanisms in colleges and universities. METHODS: In total, 781 medical college students were selected through stratified random sampling and surveyed using a questionnaire. The main factors affecting students' evaluation of emergency management were analyzed using multiple linear regression and structural equation modeling. RESULTS: The overall emergency management situation in medical colleges was relatively complete, with satisfactory results. Medical college students' satisfaction with the timeliness of prevention measures was the highest, while the publicity and education were the lowest. Multiple linear regression analysis showed that grades, emergency education, -simulation training, -information reporting, and dynamic adjustment measures were associated with the evaluation of emergency management by medical students. CONCLUSIONS: Although the evaluation of emergency management in medical colleges was generally positive, certain limitations still existed. To improve the development of the public health system, colleges and universities should constantly reform and innovate emergency management mechanisms according to the important links in the prevention and control processes.

Spatiotemporal dynamics and influencing factors of human brucellosis in Mainland China from 2005-2021.

BACKGROUND: Brucellosis poses a significant public health concern. This study explores the spatial and temporal dynamic evolution of human brucellosis in China and analyses the spatial heterogeneity of the influencing factors related to the incidence of human brucellosis at the provincial level. METHODS: The Join-point model, centre of gravity migration model and spatial autocorrelation analysis were employed to evaluate potential changes in the spatial and temporal distribution of human brucellosis in mainland China from 2005 to 2021. Ordinary Least Squares (OLS), Geographically Weighted Regression (GWR), and Multi-scale Geographically Weighted Regression (MGWR) models were constructed to analyze the spatial and temporal correlation between the incidence rate of human brucellosis and meteorological and social factors. RESULTS: From 2005 to 2021, human brucellosis in China showed a consistent upward trend. The incidence rate rose more rapidly in South, Central, and Southwest China, leading to a shift in the center of gravity from the North to the Southwest, as illustrated in the migration trajectory diagram. Strong spatial aggregation was observed. The MGWR model outperformed others. Spatio-temporal plots indicated that lower mean annual temperatures and increased beef, mutton, and milk production significantly correlated with higher brucellosis incidence. Cities like Guangxi and Guangdong were more affected by low temperatures, while Xinjiang and Tibet were influenced more by beef and milk production. Inner Mongolia and Heilongjiang were more affected by mutton production. Importantly, an increase in regional GDP and health expenditure exerted a notable protective effect against human brucellosis incidence. CONCLUSIONS: Human brucellosis remains a pervasive challenge. Meteorological and social factors significantly influence its incidence in a spatiotemporally specific manner. Tailored prevention strategies should be region-specific, providing valuable insights for effective brucellosis control measures.

Influence of HIV/AIDS knowledge on HIV testing behavior among young students (14-27 years) with a history of sexual activity: chain mediation analysis of social discrimination, self-efficacy, and sexual behavior characteristics.

This study used a self-administered questionnaire to investigate the relationship between HIV/AIDS knowledge, social discrimination, HIV self-efficacy, sexual behavioral characteristics and HIV testing behavior among young students with a history of sexual activity in Chongqing. Propensity score matching was used to construct a control group with similar demographic characteristics to the HIV testing group, only without HIV testing behaviors. Structural equation modeling was used to conduct chain-mediated effect analysis. The HIV testing rate among young students with a history of sexual behavior was 17.16%. Young students with HIV testing behavior had higher levels of HIV/AIDS knowledge, lower social discrimination, better self-efficacy, and no difference in sexual behavior characteristic scores between the two groups (P = 0.062). The mediated effect values of social discrimination and self-efficacy were 0.022 and 0.063, respectively, while their chain mediated effect value was 0.007. There was no mediated effect of sexual behavior characteristics. The level of young students' HIV/AIDS knowledge does not directly influence their HIV testing behavior but plays a complete chain mediating effect on HIV testing behavior through social discrimination and self-efficacy. HIV testing behavior should be promoted through the perspectives of enhancing HIV/AIDS knowledge level, reducing social discrimination, and improving self-efficacy.

Visible-Light-Driven Organocatalytic Alkoxylation of Benzylic C-H Bonds.

A variety of strategies for direct alkoxylation of the benzyl C-H bond have been developed toward the construction of benzyl ethers. The light-induced benzyl C-H bond alkoxylation provides an alternative strategy for the synthesis of these important intermediates. The photocatalyzed alkoxylation of the benzyl C-H bond has dominated by metal-catalyzed methods. Herein, we reported a light-driven organocatalytic approach for alkoxylation of the benzyl C-H bond by the use of 9,10-dibromoanthracene as a photocatalyst and employing N-fluorobenzenesulfonimide as an oxidant. This reaction proceeds at room temperature and is capable of converting a variety of alkyl biphenyl and coupling partners, including a variety of alcohol and carboxylic acid, as well as peroxide, to the desired products under 400 nm light irradiation.

Selective Electroreductive Hydroboration of Olefins with B2pin2.

Organoboron showed great potential in the synthesis of various high-value chemical compounds. Direct hydroboration of olefins has been witnessed over time as a mainstream method for the synthesis of organoboron compounds. In this work, an electroreductive anti-Markovnikov hydroboration approach of olefins with readily available B2pin2 to synthesize valuable organoboron compounds with high chemo- and regioselectivities under metal catalyst-free conditions was reported. This protocol exhibited broad substrate scope and good functional-group tolerance on styrenes and heteroaromatic olefins, providing synthetically useful alkylborons with high efficiency and even various deuterium borylation products with good D-incorporation when CD3CN was employed as solvent. Furthermore, gram-scale reactions and extensive functional derivatization further highlighted the potential of this method.

Study on HIV/AIDS knowledge, sexual attitudes, sexual behaviors, and preventive services among young students in Chongqing, China.

Objectives: This study aimed to describe the HIV/AIDS knowledge, sexual attitudes, and sexual behaviors of young students (14-25 years) in Chongqing, China, and to examine their use of preventive services and related factors. Method: A cross-sectional study was conducted with students from 67 schools from December 2019 to June 2021. The chi-square test, non-parametric test to assess the differences between respondents with different characteristics in the above aspects. Additionally, univariate and multivariate logistic regression analyses were conducted to examine factors associated with the awareness of HIV/AIDS knowledge. Confidence intervals without crossover or P < 0.05 was considered significant. Results: A total of 31,782 participants were included in the study. A total of 62.62% of the respondents were considered to be aware of basic HIV/AIDS knowledge, including 78.44%, 62.15%, and 52.08% in undergraduate colleges, junior colleges and secondary vocational schools, respectively. In total, 60.96% of males and 29.42% of females accepted premarital sex, 15.49% of males and 6.18% of females reported being sexually experienced, and only 57.18% of the students used condoms every time they had sex. The percentage of condom use among students who were aware of HIV/AIDS knowledge was higher than that among students who were not aware. A total of 85.60% of the students thought they needed HIV/AIDS prevention and control knowledge, and 94.60% thought more health education activities on HIV/AIDS prevention needed to be conducted in schools. Entrance education, lectures or consultation hotlines, WeChat official accounts and other media platforms were rated as the most acceptable HIV/AIDS prevention education methods. Conclusion: These respondents lacked knowledge about HIV/AIDS, and an increasing number of students show an open attitude toward premarital sex and engage in risky sexual behaviors. It is urgent to enhance and widely disseminate comprehensive HIV/AIDS and sexual health education in multiple formats.

Cr-Catalyzed Direct ortho-Aminomethylation of Phenols.

We developed a Cr-catalyzed strategy for the regioselective formation of Csp2-Csp3 bonds through the direct and efficient ortho-aminomethylation of N,N-dimethylanilines with phenols. The approach showed excellent site selectivity at the ortho-position of phenols and accommodated broad substrate scope and functional group compatibility for both N,N-dimethylanilines and phenols. Mechanistic studies revealed that the direct ortho-aminomethylation between N,N-dimethylanilines and phenols occurred via an ionic mechanism.

Manganese Catalyzed Direct Amidation of Esters with Amines.

The transition metal catalyzed amide bond forming reaction of esters with amines has been developed as an advanced approach for overcoming the shortcomings of traditional methods. The broad scope of substrates in transition metal catalyzed amidations remains a challenge. Here, a manganese(I)-catalyzed method for the direct synthesis of amides from a various number of esters and amines is reported with unprecedented substrate scope using a low catalyst loading. A wide range of aromatic, aliphatic, and heterocyclic esters, even in fatty acid esters, reacted with a diverse range of primary aryl amines, primary alkyl amines, and secondary alkyl amines to form amides. It is noteworthy that this approach provides the first example of the transition metal catalyzed amide bond forming reaction from fatty acid esters and amines. The acid-base mechanism for the manganese(I)-catalyzed direct amidation of esters with amines was elucidated by DFT calculations.

Organocatalytic Strategy for the Fixation of CO2 via Carboxylation of Terminal Alkynes.

An organocatalytic strategy for the direct carboxylation of terminal alkynes with CO2 has been developed. The combined use of a bifunctional organocatalyst and Cs2CO3 resulted in a robust catalytic system for the preparation of a range of propiolic acid derivatives in high yields with broad substrate scope using CO2 at atmospheric pressure under mild temperatures (60 °C). This work has demonstrated that this organocatalytic method offers a competitive alternative to metal catalysis for the carboxylation of terminal alkynes and CO2. In addition, this protocol was suitable for the three-component carboxylation of terminal alkynes, alkyl halides, and CO2.

Insights into Ruthenium(II/IV)-Catalyzed Distal C-H Oxygenation by Weak Coordination.

C-H hydroxylation of aryl acetamides and alkyl phenylacetyl esters was accomplished via challenging distal weak O-coordination by versatile ruthenium(II/IV) catalysis. The ruthenium(II)-catalyzed C-H oxygenation of aryl acetamides proceeded through C-H activation, ruthenium(II/IV) oxidation and reductive elimination, thus providing step-economical access to valuable phenols. The p-cymene-ruthenium(II/IV) manifold was established by detailed experimental and DFT-computational studies.

Highly Active and Robust Ruthenium Complexes Based on Hemilability of Hybrid Ligands for C-H Oxidation.

Evaluation of the hemilability of hybrid ligands provides a key to understand the metal-ligand cooperation in transition metal catalysis. Here, we design and synthesize a type of RuII complexes based on the hemilability of N-heterocyclic carbenes (NHCs), pyridine, and pyrazole, to compare their activity with other reported Ru catalysts in benzylic C-H oxidation. The RuII catalysts showed ultrastrong catalytic activity in water at room temperature and achieved a turnover frequency (TOF) of 114 h-1, which is the highest TOF value ever reported for Ru-catalyzed benzylic C-H oxidation. The addition of tridentate hybrid ligands in the Ru central position has two beneficial effects: NHCs with a stronger donor ability stabilize the Ru center; however, nitrogen ligands with a relatively weaker donor ability release from the Ru center, so that they induce a reaction. UV-vis, high-resolution electrospray ionization mass spectrometry (ESI-MS), electron paramagnetic resonance (EPR) spectrometry, the trapping of radicals, and the density functional theory calculations (DFT) suggested that a cation catalyst L-RuII-tBuO2H is formed via the reaction between starting RuII catalysts and tert-butyl hydroperoxide, which further undergoes a cleavage of the O-O bond to generate a radical and a cation L-RuIII-OH active intermediate.

Synthesis of Benzodiazepines Through Ring Opening/Ring Closure of Benzimidazole Salts.

Pyrido-benzodiazepine derivatives are undoubtedly one of the most important structural motifs in the marketed drugs and the drug candidates. Commonly synthetic methods for construction of the benzodiazepine ring derivatives are based on the condensation reactions of two highly functionalized synthons. The development of synthesis for these compounds, however, is hampered by the regioselectivity and atom economy. In this work, a one-step synthesis of pyrido-benzodiazepine backbones and its analogues is achieved through continuous ring-opening hydrolysis of benzimidazole salts and intramolecular C-H bond activation. The reaction mechanism is explored by control experiments and density functional theory (DFT) calculations.

Highly Stereo-Controlled Synthesis of Fatty Acid-Derived Cyclic Carbonates by Using Iron(II) Complex and Nucleophilic Halide.

A catalytic system comprising an iron(II) complex and a nucleophilic halide for the preparation of a series of stereo-bio-derived cyclic carbonates was developed. The protocol allows for the coupling of various cis-fatty acid-derived epoxides. For example, cis-epoxy substrates can be reacted with CO2 to selectively yield either the cis- or trans-cyclic carbonates by adjusting the nucleophilic halide. These reactions are highly stereoselective and have excellent yields even under mild reaction conditions. The stereochemical divergence in the fatty acid-derived products strongly depends on the leaving ability of the halide anion in the cocatalyst.

Cobalt-Catalyzed Hiyama-Type C-H Activation with Arylsiloxanes: Versatile Access to Highly ortho-Decorated Biaryls.

Versatile direct Hiyama-type C-H arylations of benzamides were accomplished with organosiloxanes by chelation-assisted cobalt catalysis. The C-H arylation featured broad substrate scope, including challenging C(sp3 )-H activation, the use of γ-valerolactone as biomass-derived solvent, and selectively provided the desired biaryls, even when being highly sterically hindered.

Distal Weak Coordination of Acetamides in Ruthenium(II)-Catalyzed C-H Activation Processes.

C-H activations with challenging arylacetamides were accomplished by versatile ruthenium(II) biscarboxylate catalysis. The distal C-H functionalization offers ample scope-including twofold oxidative C-H functionalizations and alkyne hydroarylations-through facile base-assisted internal electrophilic-type substitution (BIES) C-H ruthenation by weak O-coordination.

Mild C-H/C-C Activation by Z-Selective Cobalt Catalysis.

Cationic cobalt complexes enable unprecedented cobalt-catalyzed C-H/C-C functionalizations with unique selectivity features. The versatile cobalt catalyst proved broadly applicable, enabled efficient C-H/C-C cleavage at room temperature, and delivered Z-alkenes with excellent diastereocontrol.