Objective: To evaluate the current situation of thermal environment in primary and secondary school classrooms during winter, and to analyze students thermal comfort needs, so as to provide a basis for improving classroom thermal environment. Methods: From December 16 to 26, 2024, a stratified cluster random sampling method was used to select 90 classrooms from 15 primary and secondary schools in centralized/air conditioned heating areas(Liaoning Province, Tianjin City, Shanghai City) and naturally ventilated areas(Anhui Province and Jiangxi Province)for on site environmental measurement. A questionnaire survey was conducted among 743 students. The differences between groups using the χ 2 test were compared. Based on actual measurement data, a predicted mean vote prepared percentage of dissatisfied (PMV-PPD) model for centralized/air conditioned classrooms and an adaptive model for naturally ventilated classrooms were established, and the thermal neutral temperature and comfort interval were calculated. Results: The average outdoor temperature during on site measurement was 4.00(0.20，7.00)℃. In classrooms with centralized or air conditioned heating systems, the measured average temperature was (19.33±2.59)℃, with a thermal comfort range of 20.35-25.35 ℃ and a thermal neutral temperature of 22.85 ℃. And 13.92% of students reported feeling cold, while 80.80% felt comfortable. In classrooms with natural ventilation, the measured average temperature was (12.26±1.83)℃, with a thermal neutral temperature of 19.67 ℃ and a thermal comfort range of 16.17-23.17 ℃. About 48.33% of students reported feeling cold, and 49.81 % felt comfortable.The results of univariate analysis showed that there were statistically significant differences in shoe thickness, temperature sensation, relative humidity sensation and wind speed sensation between centralized/air conditioned heating areas ( χ 2= 7.01 , 31.47, 13.57, 13.80,all P <0.05). There were also statistically significant differences in school stage for primary and secondary school students, body mass index, classroom location for seat, temperature sensation, relative humidity sensation and wind speed sensation between naturally ventilated areas ( χ 2=42.13, 11.13, 11.04, 60.39, 29.27, 38.46,all P <0.05). Conclusions There are differences in thermal environment and students subjective thermal comfort in primary and secondary schools under different ventilation modes in winter. The temperature standards for heated classrooms should be revised, and differentiated environmental regulation strategies should be adopted based on different ventilation methods to improve students health and comfort levels.

Objective To explore the effect of exposure to noise of 3.0T magnetic resonance imaging(MRI)on children's cochlear function.Methods We prospectively recruited 72 children who underwent cranial MRI examination at our hospital from May to November 2018;3M earplugs and sponge mats were used for hearing protection during MRI scanning.Noise level(dBA)of each MRI sequence was detected with a nonmagnetic microphone and a sound level meter.Distortion product otoacoustic emissions(DPOAE)test at 2-7 kHz was performed 24 hours before and 30 minutes after the MRI examination.Paired t-test or Wilcoxon signed-rank test was used to analyze differences in DPOAE amplitude before and after the MRI examination.Results The average noise level of MRI measured in the study was(107.7±3.92)dBA.Compared with that before the MRI examination,the DPOAE amplitude(dB)changed little after the MRI examination;the range of amplitude differences in each age group was as follows:left ear(-0.24-1.10)and right ear(-0.24-0.74)in the 0-1 year-old group;left ear(-0.07-0.59)and right ear(-0.57-0.75)in the 2-5 year-old group;left ear(-0.36-0.44)and right ear(-0.30-0.57)in the 6-12 year-old group.No statistically significant difference was found(correction P＞0.05).Conclusion No potential impact of 3.0T MRI noise on children's cochlear function was observed under routine hearing protection.

Objective To improve the analysis of ¹³⁴Cs, ¹³⁷Cs, and ⁶⁰Co in aerosol samples by the national key radiation environment laboratories. Methods Intercomparison of analysis results of ¹³⁴Cs, ¹³⁷Cs, and ⁶⁰Co in standard aerosol samples was performed among the national key radiation environment laboratories according to Gamma spectrometry method of analyzing radionuclides in biological samples (GB/T 16145-1995 ), and the intercomparison results were evaluated by the standard deviation. Results Six laboratories were involved in the intercomparison. For ¹³⁴Cs, 50% of the laboratories showed a relative deviation less than 10%, and 50% showed a relative deviation of 10%-20%. For ¹³⁷Cs, 33.3% of the laboratories showed a relative deviation less than 10%, and 76.7% showed a relative deviation of 10%-20%. For ⁶⁰Cs, all laboratories showed a relative deviation less than 10%. The overall intercomparison results were acceptable. Conclusion The laboratories in this intercomparison show generally good results.

Objective To investigate the clinicopathological and ultrasonic characteristics of dif-ferent molecular types of breast cancer with maximum diameter ≤2 cm,and analyze the diagnostic val-ue of conventional ultrasound.Methods A total of 174 breast cancer patients with diameter ≤2 cm were selected as the study objects.According to the immunohistochemical results,they were divided in-to LA group(Luminal A,n=46),LB group(Luminal B,n=71),HER-2 group(HER-2 overexpres-sion type,n=11)and triple-negative group(triple-negative,n=46).The clinicopathology,ultrasonic characteristics and the accuracy of conventional ultrasonic diagnosis were analyzed.Results There were significant differences in breast cancer size,pathological grade and pathological type among four groups(P＜0.05).Among the ultrasonic characteristics,there were statistically significant differ-ences in shape,edge,aspect ratio,calcification and rear echo among the four groups(P＜0.05).Breast Imaging Reporting and Data System(BI-RADS)grading and accuracy of conventional ultra-sound diagnosis among the four groups showed statistically significant differences(P＜0.05).Conclusion The clinicopathological features,ultrasound features and BI-RADS grading of different molecular types of breast cancer with maximum diameter ≤2 cm are different.Routine ultrasound has certain diagnostic value,which can provide important reference for molecular classification diagnosis,individualized treatment and prognosis evaluation of early breast cancer.

Objective To investigate the clinicopathological and ultrasonic characteristics of dif-ferent molecular types of breast cancer with maximum diameter ≤2 cm,and analyze the diagnostic val-ue of conventional ultrasound.Methods A total of 174 breast cancer patients with diameter ≤2 cm were selected as the study objects.According to the immunohistochemical results,they were divided in-to LA group(Luminal A,n=46),LB group(Luminal B,n=71),HER-2 group(HER-2 overexpres-sion type,n=11)and triple-negative group(triple-negative,n=46).The clinicopathology,ultrasonic characteristics and the accuracy of conventional ultrasonic diagnosis were analyzed.Results There were significant differences in breast cancer size,pathological grade and pathological type among four groups(P＜0.05).Among the ultrasonic characteristics,there were statistically significant differ-ences in shape,edge,aspect ratio,calcification and rear echo among the four groups(P＜0.05).Breast Imaging Reporting and Data System(BI-RADS)grading and accuracy of conventional ultra-sound diagnosis among the four groups showed statistically significant differences(P＜0.05).Conclusion The clinicopathological features,ultrasound features and BI-RADS grading of different molecular types of breast cancer with maximum diameter ≤2 cm are different.Routine ultrasound has certain diagnostic value,which can provide important reference for molecular classification diagnosis,individualized treatment and prognosis evaluation of early breast cancer.

OBJECTIVE To observe the clinical efficacy and safety of albumin-bound paclitaxel combined with nedaplatin inductive chemotherapy followed by concurrent radiochemotherapy in the treatment of loco-regionally advanced nasopharyngeal carcinoma. METHODS The clinical data of 45 patients （observation group ） with loco-regionally advanced nasopharyngeal carcinoma（Ⅲ/Ⅳa stage ）who received albumin-bound paclitaxel combined with nedaplatin inductive chemotherapy in our hospital from August 2017 to July 2018 were retrospectively analyzed. Propensity score was used to match 45 patients（control group ）with loco-regionally advanced nasopharyngeal carcinoma who received docetaxel combined with cisplatin and fluorouracil inductive chemotherapy. After inductive chemotherapy ，both groups received intensity-modulated radiochemotherapy （IMRT）；observation group was additionally given concurrent nedaplatin chemotherapy ，and control groups was given concurrent cisplatin chemotherapy. Clinical efficacy and the incidence of ADR were compared between 2 groups. RESULTS All patients completed treatment and 3-year follow-up. After inductive chemotherapy and 1，3 months after concurrent radiochemotherapy ，there was no statistical significance in short-term response between 2 groups（P＞0.05）. There was no significantly difference in 3-years local control rate and 3-years free from distant metastasis between 2 groups（P＞0.05）. The incidences of leucopenia （grade 3 or above ）in the observation group were significantly lower than those in the control group ，and the incidence of peripheral neuropathy in observation group was higher than that in control group （P＜0.05）. The incidences of thrombocytopenia （grade 2 or above ），rash and vomiting （grade 2 or above ）in the observation group were lower than those in the control group ，but the difference was not statistically significant （P＞0.05）. There was no significant difference in the incidence of other ADR between 2 groups（P＞0.05）. CONCLUSIONS Albumin-bound paclitaxel combined with nedaplatin inductive chemotherapy followed by concurrent chemoradiotherapy in the treatment of loco-regionally advanced nasopharyngeal carcinoma is effective and tolerable ．

Sudden cardiac death (SCD) is one of the most common causes of death for patients with cardiovascular diseases. General practitioners are the providers of primary medical and health service, it its worthwhile to discuss their role positioning in the prevention and control system of SCD. In this study, SWOT analysis was used to explore the strength, weakness, opportunity and threats of the involvement of general practitioners in SCD prevention and control system, to clarify the roles of general practitioners and to provide suggestions for the improvement and development of SCD prevention and control system in China.

Birth cohort is an effective method to explore the relationship between various prepregnant and pregnant exposures and the health of fetuses, infants and young children. It is a long construction period to build a birth cohort and the quality of research may be affected by many factors. This paper reviews the quality assurance and quality control measures in the process of China National Birth Cohort (CNBC), and summarizes the construction experience. We aim to provide experience for related cohort studies, which could improve the quality of cohort studies through removing the impact of related factors. CNBC adopted a series of measures to ensure the quality of research in the top-level design of quality assurance, including screening research center, developing member management system, formulating standard operating procedures and training staff by it. In terms of quality control, it includes real-time, timely and timing quality control for the process of data generation, full-cycle quality control for biological sample collection, processing, storage and comprehensive three-dimensional quality control for staff training, supervision and quantitative assessment.

Objective To analyze the magnetic resonance imaging (MRI) of the spinal cord and clinical characteristics in patients with autoimmune glial fibrillary acidic protein (GFAP) astrocytopathy.Methods A total of 1 040 samples of cerebrospinal fluid (CSF) and sera collected in the Second Affiliated Hospital of Guangzhou Medical University from March 2013 to June 2018 were tested with tissue-and cell-based assays,and 42 patients were found positive for GFAP-IgG.The clinical data and MRI characteristics of the spinal cord of 19 patients who were positive for GFAP-IgG in CSF with autoimmune GFAP astrocytopathy and lesions in the spinal cord were retrospectively reviewed.Results There were 12 females and seven males among the 19 patients,with onset age of (44±17) years.The main manifestations of these patients included limb weakness (14/19),abnormal vision (5/19),headache (4/19),seizure (4/19),dementia (3/19),etc.On MRI of the spinal cord,five patients showed involvement in the cervical cord alone,eight showed involvement in the thoracic cord alone and six had both cervical and thoracic segment involvement.Fifteen patients had longitudinally extensive myelitic abnormalities (≥3 vertebral segments long).Seven enhancement patterns were encountered.Lesions were displayed in the spinal cord and brain in eight patients.Central gray matter involvement in the spinal cord was found in all the 19 patients.Conclusions Autoimmune GFAP astrocytopathy more frequently presents in females than in males.MRI of the spinal cord has complex presentations and longitudinally extensive myelitic abnormalities usually.Patients often show central gray matter involvement in the spinal cord.Myelitic abnormalities present more often in thoracic segment than in cervical segment.Abnormalities in lumbar segment are less encountered.

Objective To compare three-dimensional contrast-enhanced ultrasound ( 3DCEUS) fusion imaging and computed tomography ( CT ) fusion imaging in evaluating ablation margin ( AM ) after radiofrequency ablation ( RFA) for hepatocellular carcinoma ( HCC) . Methods The 3DCEUS images of 60 patients before and after RFA were collected . The AM was evaluated by the self-developed 3DCEUS fusion imaging technique . The consistency of AM evaluation was compared between 3DCEUS and CT fusion imaging . The risk factors of local tumor progression ( LTP) including AM were analyzed . Results The registration success rate of 3DCEUS fusion imaging was 96 .7％ ( 58/60) . Thirty-one cases were in the AM<5 mm group ,and 27 cases were in the AM ≥5 mm group . The consistency of AM evaluation between 3DCEUS and CT fusion imaging was good ( Kappa coefficient = 0 .895 , P < 0 .001) . During a follow-up period ranging 4 .2 to 18 months ,LTP was identified in 5 tumors (8 .6％ ,5/58) .The incidence of LTP with the AM<5 mm was higher than that with the AM ≥5 mm ( P =0 .033) . Conclusions 3DCEUS fusion imaging is feasible for AM evaluation immediately after RFA with high consistency with CT fusion imaging . AM<5 mm evaluated on 3DCEUS fusion immediately after RFA is a risk factor for LTP .