Abstract The study examines the development and application of microclimate standards for primary and secondary school classrooms, so as to ensure and promote the healthy growth of primary and secondary school students. The paper systematically reviews relevant domestic and international standards, analyzes the problems and shortcomings arising from their practical application and proposes effective countermeasures, in order to provide robust references aimed at optimizing the classroom environment in primary and secondary schools for student health, as well as offering practical support to advance the construction of a healthy China.

Objective: To evaluate the classroom environmental management and CO 2 volume concentration in primary and secondary schools from Liaoning, Tianjin, and Shanghai, thereby providing a scientific basis for developing targeted strategies to improve classroom air quality. Methods: From December 16 to 26, 2024, by using stratified random cluster sampling method, the questionnaire survey was conducted in 72 primary and secondary schools (24 each of primary, junior high, and regular high schools) across Liaoning, Tianjin and Shanghai. Information on heating, ventilation and other classroom environmental management was collected. Additionally, 108 classrooms were selected for on site microclimate measurements, including temperature, humidity, wind speed and CO 2 volume concentration. Univariate analysis and multiple linear regression models were employed to explore related factors of classroom CO 2 volume concentration. Results: Among the three provinces/municipalities, 20.8% of schools regularly monitored the microclimate. The overall compliance rate for classroom CO 2 volume concentration was 17.6%. Multiple linear regression analysis showed that CO 2 volume concentration in regular and junior high school classrooms were higher than in primary school classrooms ( β=0.067, 0.046, 95%CI =0.036-0.099, 0.013-0.080); classrooms ventilated regularly in the morning and afternoon had higher CO 2 volume concentration than those ventilated during every break between classes ( β=0.043, 95%CI = 0.007- 0.080); both temperature ( β=0.010, 95%CI =0.004-0.016) and humidity ( β=0.003, 95%CI =0.002-0.004) were positively correlated with CO 2 volume concentration (all P <0.05). Conclusions Excessive CO 2 volume concentration in primary and secondary school classrooms is a prominent issue, and ventilation frequency is a key intervenable factor for controlling CO 2 levels. It is recommended to promote ventilation during every break between classes as a core management measure and to emphasize air quality supervision in regular high school classrooms.

Electroencephalogram (EEG) is a non-invasive, high temporal-resolution technique for monitoring brain activity. However, affected by the volume conduction effect, EEG has a low spatial resolution and is difficult to locate brain neuronal activity precisely. The surface Laplacian (SL) technique obtains the Laplacian EEG (LEEG) by estimating the second-order spatial derivative of the scalp potential. LEEG can reflect the radial current activity under the scalp, with positive values indicating current flow from the brain to the scalp (“source”) and negative values indicating current flow from the scalp to the brain (“sink”). It attenuates signals from volume conduction, effectively improving the spatial resolution of EEG, and is expected to contribute to breakthroughs in neural engineering. This paper provides a systematic overview of the principles and development of SL technology. Currently, there are two implementation paths for SL technology: current source density algorithms (CSD) and concentric ring electrodes (CRE). CSD performs the Laplace transform of the EEG signals acquired by conventional disc electrodes to indirectly estimate the LEEG. It can be mainly classified into local methods, global methods, and realistic Laplacian methods. The global method is the most commonly used approach in CSD, which can achieve more accurate estimation compared with the local method, and it does not require additional imaging equipment compared with the realistic Laplacian method. CRE employs new concentric ring electrodes instead of the traditional disc electrodes, and measures the LEEG directly by differential acquisition of the multi-ring signals. Depending on the structure, it can be divided into bipolar CRE, quasi-bipolar CRE, tripolar CRE, and multi-pole CRE. The tripolar CRE is widely used due to its optimal detection performance. While ensuring the quality of signal acquisition, the complexity of its preamplifier is relatively acceptable. Here, this paper introduces the study of the SL technique in resting rhythms, visual-related potentials, movement-related potentials, and sensorimotor rhythms. These studies demonstrate that SL technology can improve signal quality and enhance signal characteristics, confirming its potential applications in neuroscientific research, disease diagnosis, visual pathway detection, and brain-computer interfaces. CSD is frequently utilized in applications such as neuroscientific research and disease detection, where high-precision estimation of LEEG is required. And CRE tends to be used in brain-computer interfaces, that have stringent requirements for real-time data processing. Finally, this paper summarizes the strengths and weaknesses of SL technology and envisages its future development. SL technology boasts advantages such as reference independence, high spatial resolution, high temporal resolution, enhanced source connectivity analysis, and noise suppression. However, it also has shortcomings that can be further improved. Theoretically, simulation experiments should be conducted to investigate the theoretical characteristics of SL technology. For CSD methods, the algorithm needs to be optimized to improve the precision of LEEG estimation, reduce dependence on the number of channels, and decrease computational complexity and time consumption. For CRE methods, the electrodes need to be designed with appropriate structures and sizes, and the low-noise, high common-mode rejection ratio preamplifier should be developed. We hope that this paper can promote the in-depth research and wide application of SL technology.

BACKGROUND:The formation of postoperative abdominal adhesions is a complicated process,and the prevention of postoperative adhesions is an urgent problem in clinic. OBJECTIVE:To analyze the mechanism of adhesion at cellular and molecular levels,and to provide theoretical basis for the prevention and treatment of adhesion by mesenchymal stem cell exosomes. METHODS:"Abdominal adhesion,pelvic adhesion,postoperative adhesion,epithelial mesenchymal transformation,mesenchymal stem cells,stem cell exosomes,mesenchymal stem cell exosomes"were selected as Chinese and English search terms.We searched PubMed,CNKI,and Chinese biomedical literature and screened relevant articles on postoperative abdominal adhesion and mesenchymal stem cell exosomal intervention published from inception to August 2023.After systematic analysis,54 articles were finally included for the review. RESULTS AND CONCLUSION:(1)Any pathological factors such as peritoneal inflammation,mechanical injury,tissue ischemia,and foreign body implantation cause peritoneal surface injury,resulting in postoperative abdominal adhesion.The formation process of adhesion includes the interaction of peritoneal mesothelial cell repair,inflammatory response,fibrinolytic system,coagulation pathway and other processes,involving a variety of cytokines and signaling pathways.Wnt/β-catenin pathway can induce fibrosis and angiogenesis,and cooperate with transforming growth factor-β/Smads signaling pathway to stimulate fibroblast proliferation and cause peritoneal fibrosis.Meanwhile,nuclear factor-κB signaling pathway up-regulates the expression of cellular inflammatory factors,promotes fibroblast proliferation,and plays a key role in the process of tissue fibrosis.(2)The paracrine function of stem cells is an important direction of molecular intervention in abdominal adhesions based on regenerative medicine.It can participate in a variety of complex cytokines and signaling pathways involved in abdominal adhesions.(3)Compared with traditional methods for treating abdominal adhesions,mesenchymal stem cell exosome has biological activity and is safe to use.Mesenchymal stem cell exosomes without special culture and expansion have lower immunogenicity,longer stability and other advantages,can guide a normal repair and healing through a variety of ways.(4)Mesenchymal stem cell exosome has been proven to be involved in regulating the above processes of adhesion formation in previous studies,showing potential application prospects in clinical studies.However,further clinical studies are needed to explore appropriate treatment options for mesenchymal stem cell exosomes to address the problem of clinical translation.

BackgroundPatients with schizophrenia experience low quality of life， and internalized stigma is considered an important indicator for quality of life， while the mediating role of self-esteem and severity of negative symptoms in the relationship between internalized stigma and quality of life remains underexplored. ObjectiveTo examine the mediating role of self-esteem and severity of negative symptoms in the relationship between internalized stigma and quality of life， so as to provide references for improving their quality of life. MethodsA total of 342 patients with schizophrenia who were hospitalized in 6 hospitals in Xiangyang City， Siping City and Changchun City from April to September 2023 were included， and all of whom met the diagnostic criteria for schizophrenia according to the International Classification of Diseases， tenth edition （ICD-10）. Internalized Stigma of Mental Illness Scale （ISMI）， Schizophrenia Quality of Life Scale （SQLS）， Self-Esteem Scale （SES） and negative symptom subscale of Positive and Negative Symptom Scale （PANSS） were administered to all patients. Spearman correlation analysis was adopted to determine correlations between the different scales. A structural equation modeling was constructed using Amos 28.0， and Bootstrap method was employed to verify the mediating effect of self-esteem and negative symptom severity in the association between internalized stigma and quality of life. ResultsA total of 309 patients （90.35%） completed questionnaires in this study. The ISMI score of schizophrenia patients was positively correlated with both SQLS score and the PANSS negative symptom subscale score （r=0.612， 0.492， P<0.01）， while was negatively correlated with SES score （r=-0.513， P<0.01）. The SQLS score was negatively associated with the SES score （r=-0.555， P<0.01） and positively associated with PANSS negative symptom subscale score （r=0.672， P<0.01）. The SES score was negatively correlated with PANSS negative symptom subscale score （r=-0.433， P<0.01）.The total effect value of internalized stigma on quality of life was 0.746 （95% CI： 0.680~0.806）. Self-esteem and severity of negative symptoms independently mediated the relationship between internalized stigma and quality of life， and the indirect effect values were 0.151 （95% CI： 0.062~0.254） and 0.126 （95% CI： 0.047~0.205）， accounting for 20.24% and 16.89% of the total effect， respectively. In addition， a chained mediation effect of self-esteem and quality of life was also demonstrated， the indirect effect value was 0.102 （95% CI： 0.049~0.165）， accounting for 13.67% of the total effect）. ConclusionInternalized stigma in patients with schizophrenia patients can not only directly affect the quality of life， but also indirectly affect the quality of life of patients through either separate or chained mediation of self-esteem and the severity of negative symptoms. ［Funded by Hubei Provincial Undergraduate Innovation and Entrepreneurship Project （number， S202410519027）］

Metabolites produced as intermediaries or end-products of microbial metabolism provide crucial signals for health and diseases, such as metabolic dysfunction-associated steatotic liver disease (MASLD). These metabolites include products of the bacterial metabolism of dietary substrates, modification of host molecules (such as bile acids [BAs], trimethylamine-N-oxide, and short-chain fatty acids), or products directly derived from bacteria. Recent studies have provided new insights into the association between MASLD and the risk of developing chronic kidney disease (CKD). Furthermore, alterations in microbiota composition and metabolite profiles, notably altered BAs, have been described in studies investigating the association between MASLD and the risk of CKD. This narrative review discusses alterations of specific classes of metabolites, BAs, fructose, vitamin D, and microbiota composition that may be implicated in the link between MASLD and CKD.

Metabolites produced as intermediaries or end-products of microbial metabolism provide crucial signals for health and diseases, such as metabolic dysfunction-associated steatotic liver disease (MASLD). These metabolites include products of the bacterial metabolism of dietary substrates, modification of host molecules (such as bile acids [BAs], trimethylamine-N-oxide, and short-chain fatty acids), or products directly derived from bacteria. Recent studies have provided new insights into the association between MASLD and the risk of developing chronic kidney disease (CKD). Furthermore, alterations in microbiota composition and metabolite profiles, notably altered BAs, have been described in studies investigating the association between MASLD and the risk of CKD. This narrative review discusses alterations of specific classes of metabolites, BAs, fructose, vitamin D, and microbiota composition that may be implicated in the link between MASLD and CKD.

Metabolites produced as intermediaries or end-products of microbial metabolism provide crucial signals for health and diseases, such as metabolic dysfunction-associated steatotic liver disease (MASLD). These metabolites include products of the bacterial metabolism of dietary substrates, modification of host molecules (such as bile acids [BAs], trimethylamine-N-oxide, and short-chain fatty acids), or products directly derived from bacteria. Recent studies have provided new insights into the association between MASLD and the risk of developing chronic kidney disease (CKD). Furthermore, alterations in microbiota composition and metabolite profiles, notably altered BAs, have been described in studies investigating the association between MASLD and the risk of CKD. This narrative review discusses alterations of specific classes of metabolites, BAs, fructose, vitamin D, and microbiota composition that may be implicated in the link between MASLD and CKD.

Background Existing studies suggest that cadmium exposure is associated with the occurrence of cardiovascular disease (CVD), but the current epidemiological evidence is inconsistent. Objective To systematically evaluate the relationship between cadmium exposure and CVD through meta-analysis. Methods We systematically searched PubMed, Cochrane Library, Web of Science, CNKI, Wanfang and SinoMed databases to collect observational studies on the relationship between cadmium exposure and CVD in human population published until July 30, 2024. On the basis of following predetermined inclusion and exclusion criteria, the retrieved literature was systematically screened, and the basic information of the included research was extracted, including basic participant information, research outcomes, and data results. This study used the Newcastle-Ottawa Scale and a cross-sectional study evaluation protocol (11 items) recommended by the Quality of Health Care and Research Institutions of the United States for literature quality evaluation. Meta-analysis, subgroup analysis, sensitivity analysis, and assessment of publication bias of the data were conducted using Stata16.0 software. Result A total of 15 studies (18 datasets) were included, and the quality of all the studies was graded as medium or above. Among them, there were 10593 cases of CVD and 86801 controls. The results of meta-analysis showed that the standard mean difference (SMD) of the CVD case group was 0.44 and 95% confidence interval (95%CI) was (0.30, 0.58), and the cadmium exposure level of the CVD case group was higher than that of the control group (P<0.05). The subgroup analysis showed that the cadmium exposure levels in the CVD patients from the Americas (SMD=0.46, 95%CI: 0.29, 0.63) and Europe (SMD=0.14, 95%CI: 0.09, 0.19) were higher than those in the control group (P<0.05). The cadmium levels in blood (SMD=0.52, 95%CI: 0.31, 0.73) and urine (SMD=0.34, 95%CI: 0.16, 0.52) in the CVD case group were higher than those in the control group (P<0.05). In those cross-sectional studies (SMD=0.34, 95%CI: 0.23, 0.46), the cadmium exposure level in the CVD patients was higher than that in the control group (P<0.05). The sensitivity analysis showed robust meta-analysis results and the assessment of publication bias also showed no publication bias. Conclusion Cadmium exposure may increase the risk of cardiovascular disease after multiple studies were combined by meta analysis, suggesting that the scope and level of cadmium exposure in the population should be further controlled.

OBJECTIVE To develop a long-acting light-protective nanogel with both physical barrier and chemical clearance functions， and evaluate its performance. METHODS The photoprotective nanogel composed of mussel mucin and sodium hyaluronate was constructed based on a fullerenol-cerium oxide composite nano system， namely fullerenol-cerium oxide nanogel （FCN）， and was characterized. The antioxidant capacity of FCN was evaluated using in vitro free radical scavenging experiments； its UV shielding ability was assessed by using an SPF value detector； its biosafety was assessed according to the requirements of the Guidelines for Drug Safety Evaluation； skin adhesion was assessed using small animal 3D live imaging technology； its sun protection ability was assessed through skin sunscreen detection and histopathological observation. RESULTS The average particle sizes of cerium oxide and fullerenol nanoparticles in FCN were about 20 and 10 nm， respectively， and FCN exhibited good UV absorption and free radical scavenging abilities. SPF value of FCN was 58.95±0.82， and the ultraviolet A protection level value was 6.21±0.15. No pathogenic colonies such as Staphylococcus aureus， were detected in the nanogel， and the contents of lead， arsenic， mercury and cadmium all met the standards for pharmaceutical excipients； FCN group did not show any irritating reactions such as erythema， edema， or desquamation； blood biochemical indicators of the FCN group were within the normal reference range. The material clearance rate of mice in the artificial sweat flushing group was less than 30%， while the material clearance rate of mice in the dry cleaning group reached about 92%. The mice in the protective group did not show obvious erythema or ulcer formation throughout the experiment. Histopathology showed that the fibers were arranged in an orderly manner， and the number of collagen fibers was close to that of the control group. CONCLUSIONS The FCN formulation constructed in this study meets the relevant requirements of the Chinese Pharmacopoeia， has good safety and skin compatibility， and achieves dual synergistic protection of UV shielding and free radical scavenging.