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Shunt dependent hydrocephalus (SDHC) is a common sequel after aneurysmal subarachnoid hemorrhage (aSAH) and factors contributing to the development of SDHC remain obscure. The aim of this study was to identify predictors of SDHC following aSAH. We conducted a systematic review based on the Meta-analysis of Observational Studies in Epidemiology (MOOSE) guidelines. We searched electronic databases including Pubmed, Embase, and Cochrane databases from 1980 through August 2019 for studies on the risk factors of SDHC after aSAH. Inclusion criteria were: (1) SAH and hydrocephalus confirmed by CT or magnetic resonance imaging findings; (2) the odds ratios (ORs) or the relative risk (RR) with 95% confidence interval (95%CI; or crude data that allowed their calculation) were reported; and (3) languages were restricted to English and Chinese. Two independent authors collected the data including study design, characteristics of patients and potential risk factors. Random-effects models were used to estimate weighted mean differences (WMD), relative risks (RR) with corresponding 95% confidence intervals (CI). For analysis with significant heterogeneity, subgroup analyses stratified by study design and geographic area were performed. In all, 37 cohort studies met inclusion criteria. Several factors were associated with SDHC. Infection, acute hydrocephalus, placement of external ventricular drainage, older age, higher Hunt and Hess grade, intraventricular hemorrhage, rebleeding, and mechanical ventilation were associated with greater 2-fold increased risk of SDHC. Vasospasm, female gender, high Fisher grade, preexisting hypertension, aneurysm in posterior location and intracerebral hemorrhage were associated with less than 2-fold increased risk. Treatment modality and diabetes mellitus were not associated with SDHC. SDHC is a multi-factorial disease that is associated with patient and treatment factors. Acknowledgement of these potential factors could help prevent SDHC.
Subject(s)
Hydrocephalus , Observational Studies as Topic , Subarachnoid Hemorrhage , Subarachnoid Hemorrhage/complications , Humans , Hydrocephalus/surgery , Hydrocephalus/etiology , Risk Factors , Cerebrospinal Fluid Shunts/adverse effects , Cohort StudiesABSTRACT
Multicomponent reactions hold the potential to maximize the synthetic efficiency in the preparation of diverse and complex molecular scaffolds. An unprecedented formal [3+1+1+1] annulation approach for the one-step synthesis of fluoroalkylated 2-H-pyrimidines commencing from perfluoroalkyl alkenes, paraformaldehyde, and ammonium carbonate is described. By harnessing readily accessible (CH2O)n and cheap (NH4)2CO3 as a formamidine surrogate, this method effectively replaces traditionally preformed amidines with a pyrimidine assembly. The multicomponent reaction proceeds in a step-economical, operationally simple, metal-free, and additive-free manner, featuring a broad substrate scope, excellent functional group compatibility, and scalability. The potential for the synthetic elaboration of the obtained 2-H-pyrimidine is further demonstrated in the alkylation and vinylation of its C2 position.
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Lithium-sulfur (Li-S) batteries are widely regarded as one of the most promising next-generation high-energy-density energy storage devices. However, soluble lithium polysulfides (LiPSs) corrode Li metal and deteriorate the cycling stability of Li-S batteries. Understanding the reaction mechanism between LiPSs and Li metal anode is imperative. Herein, the reaction rate and products of LiPSs with Li metal anode, the composition and structure of the as-generated solid electrolyte interphase (SEI), and the mechanism of lithium nitrate (LiNO3) additives for inhibiting the corrosion reactions are systematically unveiled. Concretely, LiPSs react with Li metal anode more rapidly than Li salt and generate a Li2S-rich SEI. The Li2S-rich SEI is highly reactive with LiPSs, which exacerbates the formation of dendritic Li and the continuous corrosion of active Li. LiNO3 functions dominantly by modulating the solvation structure of LiPSs and inherently reducing the reactivity of LiPSs, rather than the conventional understanding of LiNO3 participating in the formation of SEI. This work reveals the reaction mechanism between LiPSs and Li metal anode and inspires rational regulating of the solvation structure of LiPSs for stabilizing Li metal anode in Li-S batteries.
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Alkyne annulation has been widely used in organic synthesis for the construction of azacycles with unique structural and physicochemical properties. However, the analogous transformation of fluoroalkynes remains a challenge and has seen limited progress. Herein we report a 1,2,3,4-tetrafunctionalization of polyfluoroalkynes for the divergent construction of 5-7-membered (E)-1,2-difluorovinyl azacycles. The use of the fluorine atom as a detachable "activator" not only obviates the use of any transition metal catalysts and oxidizing reagents, but also ensures the [3-5 + 2]-annulation and defluorinative functionalization of fluoroalkynes with high chemo-, regio-, and stereoselectivities. This method exhibits a broad substrate scope, good functional group tolerance, and excellent scalability, providing a modular platform for accessing fluorinated skeletons of medicinal and biological interest. The late-stage modification of complex molecules, the multi-component 1,2-diamination of fluoroalkyne, and the synthesis of valuable organofluorides from the obtained products further highlight the real-world utility of this fluoroalkyne annulation technology.
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Purpose: In the military, neck pain is second to low back pain among musculoskeletal disorders. However, the prevalence and related factors of neck pain in military personnel have not been systematically investigated, which may lead to the lack of neck pain prevention and the generation of additional medical expenses, posing challenges to medical care. This review aimed to obtain the prevalence and related factors for neck pain in military personnel in an attempt to provide directions for prevention and intervention. Methods: We searched PubMed, Embase, and Cochrane databases in December 2021. Two researchers independently screened studies according to eligibility criteria and assessed study quality. Results: We screened titles and abstracts of 503 articles, and 17 articles met the inclusion criteria. Sixteen articles received moderate to high-quality evaluations. Neck pain is common in the military, with 1-year prevalence as high as 83% and lifetime prevalence as high as 78%. Old age (OR = 5.0), poor neck mobility (OR = 3.61), shoulder pain (OR = 4.9), low back pain (OR = 2.3), high-G pilots (OR = 1.6), longer flight time (OR = 2.53), type of aircraft (OR = 3.93), and use of helmets and night vision systems (OR = 1.9) may be associated with the prevalence of neck pain. Conclusion: Neck pain is highly prevalent in military personnel and exhibits a substantial lifetime prevalence rate. The high prevalence rate of neck pain in the military is related to many individual-related factors and work-related factors. The in-depth assessment and prevention of specific factors is an important direction of future research.
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DNA N6-methyladenine (6mA) is an important epigenetic modification that plays a vital role in various cellular processes. Accurate identification of the 6mA sites is fundamental to elucidate the biological functions and mechanisms of modification. However, experimental methods for detecting 6mA sites are high-priced and time-consuming. In this study, we propose a novel computational method, called Ense-i6mA, to predict 6mA sites. Firstly, five encoding schemes, i.e., one-hot encoding, gcContent, Z-Curve, K-mer nucleotide frequency, and K-mer nucleotide frequency with gap, are employed to extract DNA sequence features. Secondly, to our knowledge, it is the first time that eXtreme gradient boosting coupled with recursive feature elimination is applied to 6mA sites prediction domain to remove noisy features for avoiding over-fitting, reducing computing time and complexity. Then, the best subset of features is fed into base-classifiers composed of Extra Trees, eXtreme Gradient Boosting, Light Gradient Boosting Machine, and Support Vector Machine. Finally, to minimize generalization errors, the prediction probabilities of the base-classifiers are aggregated by averaging for inferring the final 6mA sites results. We conduct experiments on two species, i.e., Arabidopsis thaliana and Drosophila melanogaster, to compare the performance of Ense-i6mA against the recent 6mA sites prediction methods. The experimental results demonstrate that the proposed Ense-i6mA achieves area under the receiver operating characteristic curve values of 0.967 and 0.968, accuracies of 91.4% and 92.0%, and Mathew's correlation coefficient values of 0.829 and 0.842 on two benchmark datasets, respectively, and outperforms several existing state-of-the-art methods.
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OBJECTIVE: Adverse childhood experiences (ACEs) have been associated with a range of adverse health outcomes, with pain being potentially one of them. This population-based cross-sectional study aimed to investigate the associations between Adverse Childhood Experiences (ACEs) and pain in Chinese adults and evaluate whether physical activity and demographic and socioeconomic characteristics modify this associations. METHODS: Cross-sectional data from the China Health and Retirement Longitudinal Study (CHARLS), were utilized in this study. A total of 9923 respondents with information on 12 ACE indicators and 15 self-reported body pains were included. Logistic regression models were used to assess associations of the ACEs and pain. Modification of the associations by physical activity, demographic and socioeconomic characteristics was assessed by stratified analyses and tests for interaction. RESULTS: Among the 9923 individuals included in the primary analyses, 5098 (51.4%) males and the mean (SD) age was 61.18 (10·.44) years. Compared with individuals with 0 ACEs, those who with ≥ 5 ACEs had increased risk of single pains and multiple pain. A dose-response association was found between the number of ACEs and the risk of pain (e.g. neck pain for ≥ 5 ACEs vs. none: OR, 1.107; 95% CI, 0.903-1.356; p < 0.001 for trend). In the associations of each body pain with each ACE indicator, most ACE indicators were associated with an increased risk of pain. In addition, physical activity, sociodemographic and socioeconomic characteristics, such as age, sex, educational level, area of residence, childhood economic hardship, did not demonstrate a significant modify on the associations between ACEs and pain. CONCLUSIONS: These findings indicate that cumulative ACE exposure is associated with increased odds of self-reported pain in Chinese adults, regardless of adult physical activity, sociodemographic and socioeconomic characteristics.
Subject(s)
Adverse Childhood Experiences , Pain , Humans , Male , Female , China/epidemiology , Longitudinal Studies , Adverse Childhood Experiences/statistics & numerical data , Middle Aged , Cross-Sectional Studies , Aged , Pain/epidemiology , Exercise , Socioeconomic Factors , Risk FactorsABSTRACT
Purpose: Necroptosis, a monitored form of inflammatory cell death, contributes to coronary heart disease (CHD) progression. This study examined the potential of using necroptosis genes as diagnostic markers for CHD and sought to elucidate the underlying roles. Methods: Through bioinformatic analysis of GSE20680 and GSE20681, we first identified the differentially expressed genes (DEGs) related to necroptosis in CHD. Hub genes were identified using least absolute shrinkage and selection operator (LASSO) regression and random forest analysis after studying immune infiltration and transcription factor-miRNA interaction networks according to the DEGs. Quantitative polymerase chain reaction and immunohistochemistry were used to further investigate hub gene expression in vivo, for which a diagnostic model was constructed and the predictive efficacy was validated. Finally, the CHD group was categorized into high- and low-score groups in accordance with the single-sample gene set enrichment analysis (ssGSEA) score of the necroptosis genes. Gene Ontology, Kyoto Encyclopedia of Genes and Genomes, GSEA, and further immune infiltration analyses were performed on the two groups to explore the possible roles of hub genes. Results: Based on the results of the LASSO regression and random forest analyses, four genes were used to construct a diagnostic model to establish a nomogram. Additionally, an extensive analysis of all seventeen necroptosis genes revealed notable distinctions in expression between high-risk and low-risk groups. Evaluation of immune infiltration revealed that neutrophils, monocytes, B cells, and activated dendritic cells were highly distributed in the peripheral blood of patients with CHD. Specifically, the high CHD score group exhibited greater neutrophil and monocyte infiltration. Conversely, the high-score group showed lower infiltration of M0 and M2 macrophages, CD8+ T, plasma, and resting mast cells. Conclusion: TLR3, MLKL, HMGB1, and NDRG2 may be prospective biomarkers for CHD diagnosis. These findings offer plausible explanations for the role of necroptosis in CHD progression through immune infiltration and inflammatory response.
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Objective: This study focuses on the innovative application of Automated Machine Learning (AutoML) technology in cardiovascular medicine to construct an explainable Coronary Artery Disease (CAD) prediction model to support the clinical diagnosis of CAD. Methods: This study utilizes a combined data set of five public data sets related to CAD. An ensemble model is constructed using the AutoML open-source framework AutoGluon to evaluate the feasibility of AutoML in constructing a disease prediction model in cardiovascular medicine. The performance of the ensemble model is compared against individual baseline models. Finally, the disease prediction ensemble model is explained using SHapley Additive exPlanations (SHAP). Results: The experimental results show that the AutoGluon-based ensemble model performs better than the individual baseline models in predicting CAD. It achieved an accuracy of 0.9167 and an AUC of 0.9562 in 4-fold cross-bagging. SHAP measures the importance of each feature to the prediction of the model and explains the prediction results of the model. Conclusion: This study demonstrates the feasibility and efficacy of AutoML technology in cardiovascular medicine and highlights its potential in disease prediction. AutoML reduces the barriers to model building and significantly improves prediction accuracy. Additionally, the integration of SHAP enhances model transparency and explainability, which is critical to ensuring model credibility and widespread adoption in cardiovascular medicine.
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Improving immune function is an important indicator for establishing cold adaptation in broilers. In the study, to explore the effects and molecular mechanisms of intermittent and mild cold stimulation (IMCS) on the immune function of broilers, CIRP and TRPM8, induced by cold stimulation, as well as the NF-κB and MAPK pathways which play an important role in immune response, were selected to investigate. A total of 192 one-day-old broilers (Ross 308) were selected and randomly divided into the control group (CC) and the cold stimulation group (CS). The broilers in CC were raised at normal feeding temperature from d 1 to 43, while the broilers in CS were subjected to cold stimulation from day 15 to 35, with a temperature 3 °C below that of the CC group for 5 h, at 1 d intervals. The results showed that IMCS had little effect on the broiler hearts, and the myocardial structure was not damaged. On d 22, IMCS significantly increased the mRNA levels of CIRP, TRPM8, P65, P38, COX-2, TNF-α, IFN- γ, IL-6, IL-10, and the protein levels of CIRP, P65, P38, IL-1ß and iNOS in the hearts, and the levels of CIRP and all cytokines in the serum (P ≤ 0.05). The mRNA and protein levels of IκB-α were significantly reduced (P ≤ 0.05). On d 36, the mRNA levels of TRPM8, P65, ERK, and IL-10 in the hearts and the content of COX-2 in the serum in CS were increased significantly (P ≤ 0.05), while the mRNA levels of IκB-α, P38, and IL-1ß were decreased significantly (P ≤ 0.05). On d 43, IMCS significantly upregulated the mRNA levels of TRPM8, IFN- γ, IL-4, IL-6, IL-10, and the protein levels of IκB-α, P38, and the levels of iNOS, TNF-α, IL6 and IL10 in the serum (P ≤ 0.05); whereas it significantly downregulated CIRP, JNK, P38, iNOS, TNF-α mRNA levels, and CIRP, P65, ERK, JNK, IL1ß and iNOS protein levels (P ≤ 0.05). Therefore, IMCS can enhance broiler immune function through co-regulation of CIRP and TRPM8 on the NF-κB and MAPK pathways, which facilitate the cold adaptation in broilers.
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A three-component strategy was developed to enable hydrodefluoroamination of ß-trifluoromethyl enones by selectively activating two C(sp3)-F bonds in the trifluoromethyl group. The method involved a sequence of carbonyl reduction, hydrodefluorination, and defluoroamination under transition-metal-free conditions. Synthetically useful (E)-stereospecific α-fluoroenamides were obtained in good yields with diverse functional group tolerance, which could be easily transformed into valuable organofluorides and heterocycles. The carbonyl auxiliary exerts both electronic and steric impacts on the CF3-alkenes, allowing for controllable and selective defluorination.
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OBJECTIVE: To investigate the association of quadriceps strength with the presence of knee pain. DESIGN: This cross-sectional study was based on data from the 1999-2000 to 2001-2002 National Health and Nutrition Examination Survey. SETTING: This was a community-based study. PARTICIPANTS: This study included 2619 adults with complete data for knee pain, quadriceps strength, and covariates. INTERVENTION: Not applicable. MAIN OUTCOME MEASURES: Self-reported knee pain. RESULTS: This study included 2619 individuals, 1287 (52.66%) of whom were women and 1543 (81.66%) identified as Non-Hispanic White. The mean ±standard deviation age was 62.48±9.71 years. After adjusting for covariates, the odds of knee pain decreased with every 20 N/m increase in quadriceps strength (odds ratio, 0.87; 95% confidence interval, 0.81-0.94). Individuals in the upper quartile of quadriceps strength had lower odds of knee pain than those in the lower quartile (Q4 vs Q1 [reference]: odds ratio, 0.28, 95% confidence interval, 0.15-0.52; Ptrend=.006). Nonlinear analyses indicated L-shaped associations for knee pain. The subgroup analyses showed no significant interactions, except for sex (Pinteraction=.046). The significance of the sex interaction indicated a correlation exclusively in women. CONCLUSIONS: The results demonstrated an inverse association between quadriceps strength and the presence of knee pain. The subgroup analysis by sex showed that this inverse relationship was statistically significant in the women but not in the men subgroup.
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A silver-promoted three-component heterocyclization of alkynes, perfluoroalkyl halides, and 1,3-dinucleophiles was developed for the efficient synthesis of privileged (E)-perfluoroalkenyl pyrroles. The reaction proceeded through a rationally designed sequence of radical perfluoroalkylation and intramolecular defluorinative [3 + 2]-heterocyclization. The utility of perfluoroalkyl halide as a perfluoroalkenyl reagent, by selective and controllable functionalization of two inert C(sp3)-F bonds at vicinal carbon centers on the perfluoroalkyl chain, provides a new reaction mode for the synthesis of value-added organofluorides starting from the easily available and low-cost fluorinated feedstock.
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BACKGROUND: Migraine is one of the most common diseases worldwide while current treatment options are not ideal. New therapeutic classes of migraine, the calcitonin gene-related peptide (CGRP) antagonists, have been developed and shown considerable effectiveness and safety. The present study aimed to systematically evaluate the efficacy and safety of atogepant, a CGRP antagonist, for migraine prophylaxis from the results of randomized controlled trials (RCTs). METHODS: The Cochrane Library, Embase, PubMed and https://www. CLINICALTRIALS: gov/ were searched for RCTs that compared atogepant with placebo for migraine prophylaxis from inception of the databases to Feb 1, 2024. Outcome data involving efficacy and safety were combined and analyzed using Review Manager Software version 5.3 (RevMan 5.3). For each outcome, risk ratios (RRs) or standardized mean difference (SMD) were calculated. RESULTS: 4 RCTs with a total of 2813 subjects met our inclusion criteria. The overall effect estimate showed that atogepant was significantly superior to placebo in terms of the reduction of monthly migraine (SMD - 0.40, 95% CI -0.46 to -0.34) or headache (SMD - 0.39, 95% CI -0.46 to -0.33) days, the reduction of acute medication use days (SMD - 0.45, 95% CI -0.51 to -0.39) and 50% responder rate (RR 1.66, 95% CI 1.46 to 1.89), while no dose-related improvements were found between different dosage groups. For the safety, significant number of patients experienced treatment-emergent adverse events (TEAEs) with atogepant than with placebo (RR 1.10, 95% CI 1.02-1.21) while there was no obvious difference between the five dosage groups. Most TEAEs involved constipation (RR 2.55, 95% CI 1.91-3.41), nausea (RR 2.19, 95% CI 1.67-2.87) and urinary tract infection (RR 1.49, 95% CI 1.05-2.11). In addition, a high dosage of atogepant may also increase the risk of treatment-related TEAEs (RR 1.64, 95% CI 1.02-2.63) and fatigue (RR 3.07, 95% CI 1.13-8.35). CONCLUSIONS: This meta-analysis suggests that atogepant is effective and tolerable for migraine prophylaxis including episodic or chronic migraine compared with placebo. It is critical to weigh the benefits of different doses against the risk of adverse events in clinical application of atogepant. Longer and multi-dose trials with larger sample sizes are required to verify the current findings.
Subject(s)
Calcitonin Gene-Related Peptide Receptor Antagonists , Migraine Disorders , Migraine Disorders/prevention & control , Migraine Disorders/drug therapy , Humans , Calcitonin Gene-Related Peptide Receptor Antagonists/adverse effects , Calcitonin Gene-Related Peptide Receptor Antagonists/therapeutic use , Calcitonin Gene-Related Peptide Receptor Antagonists/administration & dosage , Randomized Controlled Trials as TopicABSTRACT
OBJECTIVE: Superselective adrenal arterial embolization (SAAE) is a potential alternative treatment for patients with unilateral primary aldosteronism (PA) who refuse unilateral adrenalectomy. Therefore, we aimed to establish a scoring model to differentiate between hypertensive remission after SAAE. METHODS: This prospective cohort study involved 240 patients who underwent SAAE for unilateral PA. Patients were randomly divided into a model training set and a validation set at a ratio of 7:3. The clinical outcome was a response to hypertension remission, defined as complete, partial, or absent success at 6 months after SAAE. Multivariate logistic regression was performed to identify independent parameters and develop a nomogram to predict clinical outcomes after SAAE. The discrimination, calibration efficacy, and clinical utility of the predictive model were assessed. RESULTS: Five independent predictors were identified: female sex, duration of hypertension, defined daily dose of antihypertensive medication, diabetes, and target organ damage. The above five independent predictors were put into a predictive model that was presented as a nomogram. Using bootstrapping for internal validation, the C-statistic for the predictive model was 0.866 (95% confidence interval [CI]: 0.834 to 0.898). In the validation cohort, the area under the curve (AUC) of the nomogram for predicting hypertension remission after SAAE was 0.809. CONCLUSION: The present model is the first nomogram-based score that specifically predicts hypertension remission after SAAE in patients with unilateral PA using conventional parameters. This is an effective risk stratification tool that can be used by clinicians for timely and tailored preoperative risk discussions.
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Cardiac hypertrophy is an adaptive response to stressors such as high cardiac workload, which might lead to abnormal cardiac function and heart failure. Previous studies have indicated that macrophage migration inhibitory factor (MIF) might play a protective role in cardiac hypertrophy. Here, we aimed to illustrate the mechanism of MIF in protecting against pressure overload-induced cardiac hypertrophy. Transverse aortic constriction (TAC) mouse model was established and we found that overexpression of MIF protected against pressure overload-induced cardiac hypotrophy in TAC treated mice, as evidenced by significantly decreased the heart weight. In addition, transthoracic echocardiography showed that overexpression of MIF restored ejection fraction in TAC-treated mice. While TAC treatment resulted in a much larger cardiomyocyte size in mice, MIF overexpression notably decreased the cardiomyocyte size. Next, we demonstrated that MIF overexpression promoted the expression of miR-29b-3p which further downregulated the expression of its downstream target HMG box protein 1 (HBP1). Overexpression of HBP1 reversed the effect of MIF in alleviating Ang-II induced oxidative stress in cardiomyocytes. In conclusion, our findings suggest that MIF could attenuate pressure overload-induced cardiac hypertrophy through regulating the miR-29b-3p/HBP1 axis.
Subject(s)
Cardiomegaly , Macrophage Migration-Inhibitory Factors , Mice, Inbred C57BL , MicroRNAs , Myocytes, Cardiac , Animals , Male , Mice , Cardiomegaly/metabolism , Cardiomegaly/genetics , HMGB1 Protein/metabolism , HMGB1 Protein/genetics , Intramolecular Oxidoreductases , Macrophage Migration-Inhibitory Factors/metabolism , Macrophage Migration-Inhibitory Factors/genetics , MicroRNAs/metabolism , MicroRNAs/genetics , Myocytes, Cardiac/metabolism , Oxidative StressABSTRACT
What is already known about this topic?: Previous research has primarily examined the issue of hepatitis B vaccine hesitancy in migrant workers and other adult populations. However, there is a lack of studies that have specifically investigated the prevalence of hepatitis B vaccine hesitancy among university students. What is added by this report?: In this study, 19.84% of students expressed hesitancy towards receiving the hepatitis B immunization. A negative correlation was observed between hepatitis B vaccine hesitancy and knowledge, attitudes, and practices related to hepatitis B. Conversely, a positive relationship was identified between hepatitis B-related knowledge and attitudes and practices. What are the implications for public health practice?: This study examines the factors contributing to vaccine hesitancy towards hepatitis B at a medical university in China. The results have significant implications for developing strategies to improve hepatitis B vaccination rates.
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Super sulfate cement (SSC) emerges as a sustainable alternative to ordinary Portland cement, boasting minimal carbon emissions and exceptional performance. As the quest for eco-friendly alternatives intensifies, there's a growing focus on exploring alkaline and sulfate activators conducive to SSC's environmental goals. This study delves into the viability of utilizing MgO as an alkaline activator in producing MgO-based supersulfated cement, while also investigating the impact of various industrial by-product gypsums on its performance. Findings reveal that employing MgO as an alkaline activator yields favorable hydration properties and mechanical strength in SSC. The optimized formulation comprises 15 % industrial by-product gypsum, 83 % granulated blast furnace slag (GGBFS), and 2 % MgO. Incorporating building gypsum and flue gas desulfurization (FGD) gypsum demonstrates superior unconfined compressive strength (UCS) growth compared to citric gypsum and phosphogypsum. Notably, gel-pores below 20 nm dominate the matrix, with variations in their distribution linked to the gypsum type used. The pH level and crystal structure of the industrial by-product gypsum emerge as pivotal factors dictating the hydration process. The interaction energy between hydrated building gypsum crystal planes and water molecules proves lower, contributing to the root cause of its high sulfate activating capability. Compared to traditional SSC, MgO-based supersulfated cement requires less alkaline activator content and accommodates more industrial by-product gypsums, thus reducing costs, CO2 emissions, and promoting the efficient utilization of these solid wastes.
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The electronic, optical and photocatalytic properties of GaN/C2N van der Waals heterostructures are investigated using the first-principles theory, and effective regulation through element doping or strain is achieved further. The results show that the GaN/C2N heterostructure exhibits a type-II band alignment with an indirect band gap of 2.25 eV, which benefits photocatalytic water splitting. In this study, both type-I and type-II band alignments can be obtained through doping or strain modulation. Doping with P or As atoms reduces the band gap of the GaN/C2N heterostructure and transforms it to a type-I direct bandgap semiconductor, which makes the doped GaN/C2N heterostructure more suitable for optoelectronic devices. In addition, the GaN/C2N heterostructure retains type-II band alignment and has a decreased band gap under tensile strain (0 to +4%), which is more favorable for photocatalytic water splitting. Compressive strain (0 to -4%) converts the type-II band alignment to type-I, resulting in a wider light absorption range, making the GaN/C2N heterostructure more suitable for optoelectronic devices. These theoretical results are helpful for the design of GaN/C2N vdW heterostructures in the fields of optoelectronic devices and photocatalysts.
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Solid polymer electrolytes are promising electrolytes for safe and high-energy-density lithium metal batteries. However, traditional ether-based polymer electrolytes are limited by their low lithium-ion conductivity and narrow electrochemical window because of the well-defined and intimated Li+-oxygen binding topologies in the solvation structure. Herein, we proposed a new strategy to reduce the Li+-polymer interaction and strengthen the anion-polymer interaction by combining strong Li+-O (ether) interactions, weak Li+-O (ester) interactions with steric hindrance in polymer electrolytes. In this way, a polymer electrolyte with a high lithium ion transference number (0.80) and anion-rich solvation structure is obtained. This polymer electrolyte possesses a wide electrochemical window (5.5â V versus Li/Li+) and compatibility with both Li metal anode and high-voltage NCM cathode. Li||LiNi0.5Co0.2Mn0.3O2 full cells with middle-high active material areal loading (~7.5â mg cm-2) can stably cycle at 4.5â V. This work provides new insight into the design of polymer electrolytes for high-energy-density lithium metal batteries through the regulation of ion-dipole interactions.