ObjectiveThe frequency difference limen (FDL) serves as a fundamental metric utilized for effectively quantifying the precise perceptual capabilities of the central auditory system. However, traditional measurement methods rely heavily on the active behavioral responses of subjects and are consequently highly susceptible to the negative influence of confounding subjective factors. Furthermore, existing research paradigms frequently employ uniform stimulus configurations that overlook critical individual perceptual differences. Based on brain-computer interface (BCI) technology, this comprehensive study aims to establish an objective and quantitative evaluation method for auditory frequency discrimination by systematically analyzing and decoding the specific neural responses elicited at the exact threshold state. MethodsWe designed a personalized rapid serial auditory presentation (RSAP) paradigm customized based on each individual’s precise FDL. A cohort of eleven healthy participants was recruited to evaluate the paradigm using pure-tone sequences at a baseline frequency of 4 000 Hz. This experimental paradigm simulates a realistic auditory perception environment through the continuous presentation of acoustic stimuli, thereby allowing for an in-depth investigation into the specific neural representations evoked by weak frequency deviations at the threshold state. Given that auditory stimulus-evoked response features exhibit complex and differentiated spatiotemporal distribution patterns across multiple frequency domains, this study further deeply integrates the cross-scale feature interaction module with the dynamic spatiotemporal attention allocation strategy, innovatively proposing the Multi-Scale Spatial-Temporal Dual Attention Network (MS-STAMNet). Specifically, the network constructs parallel processing branches with multiple receptive fields and introduces a dynamic adaptive weighting strategy to precisely localize core neural activity signals, further deeply integrating multi-scale information through cross-branch feature information interaction to achieve robust single-trial decoding of weak auditory evoked responses. ResultsThe comprehensive electrophysiological data analysis demonstrated that subtle auditory frequency deviation stimuli presented at the threshold level successfully elicited pronounced N2 and P3 event-related potential features, reflecting pre-attentive mismatch detection and subsequent cognitive evaluation, which were prominently distributed over the frontal, central, and temporal regions of the scalp. In the complex time-frequency domain, the extracted neural response characteristics exhibited distinct, statistically significant event-related synchronization within both the low-frequency δ and θ frequency bands, which was simultaneously accompanied by a widespread, prominent event-related desynchronization within the higher α band. A comparative analysis of model performance demonstrated that MS-STAMNet achieved an average unweighted average recall (UAR) of (69.67±6.12)% and area under the curve (AUC) of 0.761 8±0.07, significantly outperforming the established baseline models such as EEGNet and PLNet. Furthermore, a distinct dissociation phenomenon was verified between neural decoding and behavioral performance through regression analysis (R²=0.016, P=0.709), indicating that this model can effectively capture the implicit features of subtle frequency deviations, even when they fail to trigger explicit conscious responses. Additionally, attention weight visualization analysis further reveals the highly accurate focus of the network on key features concentrated over the bilateral temporal and fronto-parietal regions. ConclusionThis study systematically and comprehensively uncovers the multi-dimensional spatiotemporal evolutionary patterns of complex neural responses processing subtle acoustic variations under long-sequence threshold auditory stimulation. Concurrently, it verifies the efficacy and robustness of the proposed MS-STAMNet architecture in accurately deciphering weak, single-trial electroencephalogram signals amidst complex background noise. Ultimately, these neurophysiological and algorithmic findings lay a solid theoretical and methodological foundation for the objective and quantitative evaluation of individual auditory cognitive capabilities in clinical applications, transcending the fundamental limitations of traditional behavioral paradigms and providing robust technical support for future auditory research and related clinical assessments.

To systematically evaluate the impact of the "group-based " medical assistance program for Xizang, conducted by Peking Union Medical College Hospital, on the implementation outcomes of standardized residency training (SRT) at the Xizang Autonomous Region People′s Hospital, and to provide evidence-based decision-making references and policy optimization recommendations for medical education support models in border ethnic minority regions.

Kounis syndrome is an acute coronary syndrome triggered by an allergic reaction, which is clinically rare and frequently subject to misdiagnosis or missed diagnosis. This article presents a case report of a 70-year-old male patient who developed a rash, pruritus, and chest pain following colon polyp resection. Coronary angiography revealed occlusion of the left anterior descending artery, and blood flow was restored after stent implantation. However, the patient experienced recurrent symptoms accompanied by loss of consciousness. Drug skin tests confirmed positive reactions to chlorhexidine and fondaparinux sodium, leading to a diagnosis of type Ⅱ Kounis syndrome. By avoiding allergenic drugs and combining antihistamines with symptomatic treatment to correct myocardial ischemia, the patient′s clinical symptoms significantly improved, and he eventually recovered and was discharged from the hospital. This case underscores the importance of maintaining vigilance for this syndrome in patients with allergies accompanied by chest pain and promptly identifying and avoiding allergens.

Objective:To explore the relationships between physical activity and cognitive impairment in older adults aged ≥65 years in longevity areas in China.Methods:A total of 6 081 older adults aged ≥65 years from the Healthy Ageing and Biomarkers Cohort Study in China in 2021 were included in this study. Information about their demographic characteristics, lifestyles, and chronic disease histories were collected, the intensity of physical activity was evaluated by using Physical Activity Scale for the Elderly, and the cognitive function was evaluated by using Mini-Mental State Examination Scale (Chinese version). Multifactorial logistic regression model was used to analyze the associations between different levels and types of physical activity and cognitive impairment in older adults.Results:In the 6 081 older adults, 1 829 (30.1%) had cognitive impairment. After adjusting for confounders, older adults with T2 and T3 levels of physical activity had lower risks for cognitive impairment compared with those with T1 levels of physical activity, with ORs of 0.47 (95% CI: 0.40-0.55) and 0.22 (95% CI: 0.18-0.28). The results of different types of physical activities showed that the ORs in leisure activity T2 and T3 groups were 0.52 (95% CI: 0.44-0.63) and 0.49 (95% CI: 0.41-0.58), and the ORs in housework activity T2 and T3 groups were 0.36 (95% CI: 0.30-0.42) and 0.19 (95% CI: 0.16-0.24). There was no significant association between work-related activity and cognitive impairment. Conclusion:There is a negative association between the intensity level of physical activity and cognitive impairment, and active leisure and household activities might reduce the risk for cognitive impairment.

Objective:To explore the relationships between physical activity and cognitive impairment in older adults aged ≥65 years in longevity areas in China.Methods:A total of 6 081 older adults aged ≥65 years from the Healthy Ageing and Biomarkers Cohort Study in China in 2021 were included in this study. Information about their demographic characteristics, lifestyles, and chronic disease histories were collected, the intensity of physical activity was evaluated by using Physical Activity Scale for the Elderly, and the cognitive function was evaluated by using Mini-Mental State Examination Scale (Chinese version). Multifactorial logistic regression model was used to analyze the associations between different levels and types of physical activity and cognitive impairment in older adults.Results:In the 6 081 older adults, 1 829 (30.1%) had cognitive impairment. After adjusting for confounders, older adults with T2 and T3 levels of physical activity had lower risks for cognitive impairment compared with those with T1 levels of physical activity, with ORs of 0.47 (95% CI: 0.40-0.55) and 0.22 (95% CI: 0.18-0.28). The results of different types of physical activities showed that the ORs in leisure activity T2 and T3 groups were 0.52 (95% CI: 0.44-0.63) and 0.49 (95% CI: 0.41-0.58), and the ORs in housework activity T2 and T3 groups were 0.36 (95% CI: 0.30-0.42) and 0.19 (95% CI: 0.16-0.24). There was no significant association between work-related activity and cognitive impairment. Conclusion:There is a negative association between the intensity level of physical activity and cognitive impairment, and active leisure and household activities might reduce the risk for cognitive impairment.

Objective To investigate the correlation between the level of N-terminal pro-Brain natriuretic peptide(NT-proBNP)and cardiorespiratory fitness following acute exposure to high altitude.Methods Forty-six subjects were recruited from the Second Affiliated Hospital of Army Medical University in June 2022,including 19 males and 27 females.After completing cardiopulmonary exercise test(CPET),serological detection of myocardial cell-related markers,and multiple metabolites at a plain altitude(300 meters above sea level),all subjects flew to a high-altitude location(3900 meters above sea level).Biomarker testing and CPET were repeated on the second and third days after arrival at high altitude.Changes in serum biomarker and key CPET indicators before and after rapid ascent to high altitude were compared,and the correlation between serum levels of various myocardial cell-related markers and metabolites and high altitude cardiorespiratory fitness was analyzed.Results Compared with the plain altitude,there was a significant decrease in maximal oxygen uptake after rapid ascent to high altitude[(25.41±6.20)ml/(kg.min)vs.(30.17±5.01)ml/(kg.min),P<0.001].Serum levels of NT-proBNP,Epinephrine(E),plasma renin activity(PRA),angiotensin Ⅱ(Ang Ⅱ),angiotensin-converting enzyme 2(ACE2)and leptin(LEP)significantly increased,with all differences being statistically significant(P<0.05)after acute high altitude exposure.In contrast,no statistically significant differences were observed for creatine kinase MB(CK-MB),cardiac troponin I(cTnI),myoglobin(Myo)and norepinephrine(NE)(P>0.05).Correlation analysis showed a significant negative correlation between NT-proBNP at plain altitude(r=-0.768,P<0.001)and at high altitude(r=-0.791,P<0.001)with maximal oxygen uptake at high altitude.Multivariate linear regression analysis indicated that maximal oxygen uptake at plain altitude(t=2.069,P=0.045),NT-proBNP at plain altitude(t=-2.436,P=0.020)and at high altitude(t=-3.578,P=0.001)were independent influencing factors of cardiorespiratory fitness at high altitude.Conclusion Cardiorespiratory fitness significantly decreases after rapid ascent to high altitude,and the baseline NT-proBNP level at plain altitude is closely related to cardiorespiratory fitness at high altitude,making it a potential predictor indicator for high altitude cardiorespiratory fitness.

Objective To design a novel oxygenator to solve the existing problems of extracorporeal membrane oxygenation(ECMO)machine in high transmembrane pressure difference,low efficiency of blood oxygen exchange and susceptibility to thrombosis.Methods The main body of the oxygenator vascular access flow field was gifted with a flat cylindrical shape.The topology of the vascular access was modeled in three dimensions,and the whole flow field was cut into a blood inlet section,an inlet buffer,a heat exchange zone,a blood oxygen exchange zone,an outlet buffer and a blood outlet section.The oxygenator was compared with Quadrox oxygenator by means of ANSYS FLUENT-based simulation and prototype experiments.Results Simulation calculations showed the oxygenator designed was comparable to the clinically used ones in general,and gained advantages in transmembrane pressure difference,blood oxygen exchange and flow uniformity.Experimental results indicated that the oxygenator behaved better than Quadrox oxygenator in transmembrane pressure difference and blood oxygen exchange.Conclusion The oxygenator has advantages in transmem-brane pressure difference,temperature change,blood oxygen ex-change and low probability of thrombosis.[Chinese Medical Equipment Journal,2024,45(3):23-28]

ObjectiveTo identify acute phase features associated with the prognosis of traumatic brain injury （TBI）. MethodsThrough two traditional strategies， correlation analysis and prediction model， and one innovative research strategy based on feature deconstruction， a retrospective analysis was conducted using demographic， acute phase and chronic phase features of 354 TBI patients to identify acute phase features associated with activities of daily living （ADL） in chronic phase of TBI. For feature deconstruction strategy， the LASSO （Least Absolute Shrinkage and Selection Operator） algorithm was used to build a prediction model that could effectively predict ADL based on non-ADL chronic phase features. The model could indicate the key chronic phase dimensions determining the ADL in TBI patients. We then identified demographic and acute phase variables that were significantly associated with these key chronic phase features. ResultsThe feature deconstruction strategy revealed that ADL could be deconstructed into chronic phase dimensions such as weak limbs in TBI population. Importantly， to the best of our knowledge， this strategy revealed for the first time the association of these important acute phase features with specific chronic phase impairment features. For example， TBI patients had a higher risk for chronic phase recent memory impairment if they had a prolonged coma time and low GCS scores at acute phase ［scaled coma time OR95%CI = 94.288 （35.095， 273.231）； scaled GCS OR95%CI = 0.068 （0.030， 0.147）］； the patients had a higher risk for insight impairment and disorientation at chronic phase if they had hydrocephalus at acute phase ［insight impairment OR95%CI = 6.760 （3.653，12.855） ； disorientation OR95%CI = 6.538 （3.530， 12.490）］. All strategies showed that the strongest risk factors for ADL damage in the chronic phase included prolonged coma time and low GCS scores as well as hydrocephalus. ConclusionThis study provides an innovative research strategy to establish the association between acute injury features and chronic recovery features， and to identify demographic and acute phase features associated with the prognosis of TBI.

OBJECTIVE: To evaluate the associations of lipid indicators and mortality in Beijing Elderly Comprehensive Health Cohort Study. METHODS: A prospective cohort was conducted based on Beijing Elderly Comprehensive Health Cohort Study with 4499 community older adults. After the baseline survey, the last follow-up was March 31, 2021 with an average 8.13 years of follow-up. Cox proportional hazard model was used to estimate the hazard ratios (HR) with 95% CI for cardiovascular disease (CVD) death and all-cause death in associations with baseline lipid indicators. RESULTS: A total of 4499 participants were recruited, and the mean levels of uric acid, body mass index, systolic blood pressure, diastolic blood pressure, fasting plasma glucose, total cholesterol (TC), triglyceride, and low-density lipoprotein cholesterol (LDL-C) showed an upward trend with the increasing remnant cholesterol (RC) quarters (P_trend < 0.05), while the downward trend was found in high-density lipoprotein cholesterol (HDL-C). During the total 36,596 person-years follow-up, the CVD mortality and all-cause mortality during an average 8.13 years of follow-up was 3.87% (95% CI: 3.30%-4.43%) and 14.83% (95% CI: 13.79%-15.86%) with 174 CVD death participants and 667 all-cause death participants. After adjusting for confounders, the higher level of TC (HR = 0.854, 95% CI: 0.730-0.997), LDL-C (HR = 0.817, 95% CI: 0.680-0.982) and HDL-C (HR = 0.443, 95% CI: 0.271-0.724) were associated with lower risk of CVD death, and the higher level of HDL-C (HR = 0.637, 95% CI: 0.501-0.810) were associated with lower risk of all-cause death. The higher level of RC (HR = 1.276, 95% CI: 1.010-1.613) increase the risk of CVD death. Compared with the normal lipid group, TC ≥ 6.20 mmol/L group and LDL-C ≥ 4.10 mmol/L group were no longer associated with lower risk of CVD death, while RC ≥ 0.80 mmol/L group was still associated with higher risk of CVD death. In normal lipid group, the higher levels of TC, LDL-C and HDL-C were related with lower CVD death. CONCLUSIONS In community older adults, higher levels of TC and HDL-C were associated with lower CVD mortality in normal lipid reference range. Higher RC was associated with higher CVD mortality, which may be a better lipid indicator for estimating the CVD death risk in older adults.

Objective: This cross-sectional investigation aimed to determine the incidence, clinical characteristics, prognosis, and related risk factors of olfactory and gustatory dysfunctions related to infection with the SARS-CoV-2 Omicron strain in mainland China. Methods: Data of patients with SARS-CoV-2 from December 28, 2022, to February 21, 2023, were collected through online and offline questionnaires from 45 tertiary hospitals and one center for disease control and prevention in mainland China. The questionnaire included demographic information, previous health history, smoking and alcohol drinking, SARS-CoV-2 vaccination, olfactory and gustatory function before and after infection, other symptoms after infection, as well as the duration and improvement of olfactory and gustatory dysfunction. The self-reported olfactory and gustatory functions of patients were evaluated using the Olfactory VAS scale and Gustatory VAS scale. Results: A total of 35 566 valid questionnaires were obtained, revealing a high incidence of olfactory and taste dysfunctions related to infection with the SARS-CoV-2 Omicron strain (67.75%). Females(χ2=367.013, P<0.001) and young people(χ2=120.210, P<0.001) were more likely to develop these dysfunctions. Gender(OR=1.564, 95%CI: 1.487-1.645), SARS-CoV-2 vaccination status (OR=1.334, 95%CI: 1.164-1.530), oral health status (OR=0.881, 95%CI: 0.839-0.926), smoking history (OR=1.152, 95%CI=1.080-1.229), and drinking history (OR=0.854, 95%CI: 0.785-0.928) were correlated with the occurrence of olfactory and taste dysfunctions related to SARS-CoV-2(above P<0.001). 44.62% (4 391/9 840) of the patients who had not recovered their sense of smell and taste also suffered from nasal congestion, runny nose, and 32.62% (3 210/9 840) suffered from dry mouth and sore throat. The improvement of olfactory and taste functions was correlated with the persistence of accompanying symptoms(χ2=10.873, P=0.001). The average score of olfactory and taste VAS scale was 8.41 and 8.51 respectively before SARS-CoV-2 infection, but decreased to3.69 and 4.29 respectively after SARS-CoV-2 infection, and recovered to 5.83and 6.55 respectively at the time of the survey. The median duration of olfactory and gustatory dysfunctions was 15 days and 12 days, respectively, with 0.5% (121/24 096) of patients experiencing these dysfunctions for more than 28 days. The overall self-reported improvement rate of smell and taste dysfunctions was 59.16% (14 256/24 096). Gender(OR=0.893, 95%CI: 0.839-0.951), SARS-CoV-2 vaccination status (OR=1.334, 95%CI: 1.164-1.530), history of head and facial trauma(OR=1.180, 95%CI: 1.036-1.344, P=0.013), nose (OR=1.104, 95%CI: 1.042-1.171, P=0.001) and oral (OR=1.162, 95%CI: 1.096-1.233) health status, smoking history(OR=0.765, 95%CI: 0.709-0.825), and the persistence of accompanying symptoms (OR=0.359, 95%CI: 0.332-0.388) were correlated with the recovery of olfactory and taste dysfunctions related to SARS-CoV-2 (above P<0.001 except for the indicated values). Conclusion: The incidence of olfactory and taste dysfunctions related to infection with the SARS-CoV-2 Omicron strain is high in mainland China, with females and young people more likely to develop these dysfunctions. Active and effective intervention measures may be required for cases that persist for a long time. The recovery of olfactory and taste functions is influenced by several factors, including gender, SARS-CoV-2 vaccination status, history of head and facial trauma, nasal and oral health status, smoking history, and persistence of accompanying symptoms.
Female ; Humans ; Adolescent ; SARS-CoV-2 ; Smell ; COVID-19/complications* ; Cross-Sectional Studies ; COVID-19 Vaccines ; Incidence ; Olfaction Disorders/etiology* ; Taste Disorders/etiology* ; Prognosis