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Numerical simulations for radon migration and exhalation behavior during measuring radon exhalation rate with closed-loop method

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Nuclear Science and Techniques 2024年第1期35卷 81-95页

作者： Ming Xia Yong-Jun ye shu-Yuan Liu School of Resources Environment and Safety Engineering University of South ChinaHengyang 421001China Key Discipline Laboratory for National Defense for Biotechnology in Uranium Mining and Hydrometallurgy University of South ChinaHengyang 421001China

Accurate measurements of the radon exhalation rate help identify and evaluate radon risk regions in the environment.Among these measurement methods,the closed-loop method is frequently used.However,traditional experiments are insufficient or cannot analyze the radon migration and exhalation patterns at the gas–solid interface in the accumulation chamber.The CFD-based technique was applied to predict the radon concentration distribution in a limited space,allowing radon accumulation and exhalation inside the chamber intuitively and visually.In this study,three radon exhalation rates were defined,and two structural ventilation tubes were designed for the chamber.The consistency of the simulated results with the variation in the radon exhalation rate in a previous experiment or analytical solution was verified.The effects of the vent tube structure and flow rate on the radon uniformity in the chamber;permeability,insertion depth,and flow rate on the radon exhalation rate and the effective diffusion coefficient on back-diffusion were investigated.Based on the results,increasing the inser-tion depth from 1 to 5 cm decreased the effective decay constant by 19.55%,whereas the curve-fitted radon exhalation rate decreased(lower than the initial value)as the deviation from the initial value increased by approximately 7%.Increasing the effective diffusion coefficient from 2.77×10^(-7) to 7.77×10^(-6) m^(2) s^(-1) made the deviation expand from 2.14 to 15.96%.The conclusion is that an increased insertion depth helps reduce leakage in the chamber,subject to notable back-diffusion,and that the closed-loop method is reasonably used for porous media with a low effective diffusion coefficient in view of the back-diffusion effect.The CFD-based simulation is expected to provide guidance for the optimization of the radon exhalation rate measurement method and,thus,the accurate measurement of the radon exhalation rate.

关键词： Radon exhalation Numerical simulation Accumulation chamber

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Numerical Simulation on Radon Retardation Behavior of Covering Floats in Radon-Containing Water

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Biomedical and Environmental Sciences 2024年第4期37卷 406-417页

作者： LIU shu Yuan ZHANG Li ye Yong Jun DING Ku Ke National Institute for Radiological Protection Chinese Center for Disease Control and PreventionBeijing 100088China Office for Public Health Management Chinese Center for Disease Control and PreventionBeijing 102206China Key Discipline Laboratory for National Defense for Biotechnology in Uranium Mining and Hydrometallurgy University of South ChinaHengyang 421001HunanChina

Objective This study aimed to efficiently reduce the release of radon from water bodies to protect the environment.Methods Based on the sizes of the experimental setup and modular float,computational fluid dynamics(CFD)was used to assess the impact of the area coverage rate,immersion depth,diffusion coefficient,and radon transfer velocity at the gas–liquid interface on radon migration and exhalation of radon-containing water.Based on the numerical simulation results,an estimation model for the radon retardation rate was constructed.The effectiveness of the CFD simulation was evaluated by comparing the experimental and simulated variation values of the radon retardation rate with the coverage area rates.Results The effect of radon transfer velocity on radon retardation in water bodies was minor and insignificant according to the appropriate value;therefore,an estimation model of the radon retardation rate of the coverage of a radon-containing water body was constructed using the synergistic impacts of three factors:area coverage rate,immersion depth,and diffusion coefficient.The deviation between the experimental and simulated results was<4.3%.Conclusion Based on the numerical simulation conditions,an estimation model of the radon retardation rate of covering floats in water bodies under the synergistic effect of multiple factors was obtained,which provides a reference for designing covering floats for radon retardation in radoncontaining water.

关键词： Radon-containing water Radon retardation rate CFD Coverage experiment Optimized design

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Special electromyographic features in a child with paramyotonia congenita: A case report and review of literature

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World Journal of Clinical Cases 2024年第3期12卷 587-595页

作者： Hui Yi Chen-Xiang Liu shu-Xin ye Yu-Lin Liu Department of Neuroelectrophysiology Qilu Children’s Hospital of Shandong UniversityJinan 250000Shandong ProvinceChina Department of Neuroelectrophysiology University of Health and Rehabilitation Sciences(Qingdao Municipal Hospital)Qingdao 266000Shandong ProvinceChina

BACKGROUND Paramyotonia congenita(PMC)stands as a rare sodium channelopaty of skeletal muscle,initially identified by Eulenburg.The identification of PMC often relies on electromyography(EMG),a diagnostic technique.The child’s needle EMG unveiled trains of myotonic discharges with notably giant amplitudes,alongside irregular wave trains of myotonic discharges.This distinctive observation had not surfaced in earlier studies.CASE SUMMARY We report the case of a 3-year-old female child with PMC,who exhibited la-ryngeal stridor,muffled speech,myotonia from birth.Cold,exposure to cool water,crying,and physical activity exacerbated the myotonia,which was relieved in warmth,yet never normalized.Percussion myotonia was observable in bilateral biceps.Myotonia symptoms remained unchanged after potassium-rich food consumption like bananas.Hyperkalemic periodic paralysis was excluded.Cranial magnetic resonance imaging yielded normal results.Blood potassium remained within normal range,while creatine kinase showed slight elevation.Exome-wide genetic testing pinpointed a heterozygous mutation on chromosome SCN4A:c.3917G>A(p.G1306E).After a six-month mexiletine regimen,symptoms alleviated.CONCLUSION In this case revealed the two types of myotonic discharges,and had not been documented in other studies.We underscore two distinctive features:Giant-amplitude potentials and irregular waves.

关键词： Paramyotonia congenita Channelopathy Electromyography Child Case report

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A Comparative Study on the Post-Buckling Behavior of Reinforced Thermoplastic Pipes(RTPs)Under External Pressure Considering Progressive Failure

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China Ocean Engineering 2024年第2期38卷 233-246页

作者： DING Xin-dong WANG shu-qing LIU Wen-cheng ye Xiao-han College of Engineering Ocean University of ChinaQingdao 266100China Shandong Provincial Key Laboratory of Ocean Engineering Ocean University of ChinaQingdao 266100China Department of Marine Technology Norwegian University of Science and Technology(NTNU)Trondheim NO-7491Norway

The collapse pressure is a key parameter when RTPs are applied in harsh deep-water environments.To investigate the collapse of RTPs,numerical simulations and hydrostatic pressure tests are conducted.For the numerical simulations,the eigenvalue analysis and Riks analysis are combined,in which the Hashin failure criterion and fracture energy stiffness degradation model are used to simulate the progressive failure of composites,and the“infinite”boundary conditions are applied to eliminate the boundary effects.As for the hydrostatic pressure tests,RTP specimens were placed in a hydrostatic chamber after filled with water.It has been observed that the cross-section of the middle part collapses when it reaches the maximum pressure.The collapse pressure obtained from the numerical simulations agrees well with that in the experiment.Meanwhile,the applicability of NASA SP-8007 formula on the collapse pressure prediction was also discussed.It has a relatively greater difference because of the ignorance of the progressive failure of composites.For the parametric study,it is found that RTPs have much higher first-ply-failure pressure when the winding angles are between 50°and 70°.Besides,the effect of debonding and initial ovality,and the contribution of the liner and coating are also discussed.

关键词： reinforced thermoplastic pipes post-buckling behavior progressive failure of composites debonding initial ovality

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Ki-67 Change in Anthracyline-containing Neoadjuvant Chemotherapy Response in Breast Cancer

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Current Medical Science 2024年第1期44卷 156-167页

作者： Zi-guo YANG Le-hao REN Feng WANG Pi-lin WANG Wen-yan WANG shu-ye LIN Department of General Surgery Beijing Tiantan HospitalCapital Medical UniversityBeijing 100070China Department of Critical Care Medicine Union HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhan 430022China Cancer Research Center Beijing Chest HospitalCapital Medical University/Beijing Tuberculosis and Thoracic Tumor Research InstituteBeijing 101149China

Objective Anthracycline-containing regimens are irreplaceable in neoadjuvant chemotherapy(NAC)for breast cancer(BC)at present.However,30% of early breast cancer(EBC)patients are resistant to anthracycline-containing chemotherapy,leading to poor prognosis and higher mortality.Ki-67 is associated with the prognosis and response to therapy,and it changes after NAC.Methods A total of 105 BC patients who received anthracycline-containing NAC were enrolled.Then,the optimal model of Ki-67 was selected,and its predictive efficacy was analyzed.Immunohistochemistry(IHC)was used to determine the estrogen receptor(ER),progesterone receptor(PR),and human epidermal growth factor receptor 2(HER-2)status and Ki-67 level.Fluorescent in situ hybridization(FISH)was used to verify the HER-2 when the IHC score was 2+.Results The post-NAC Ki67 level after treatment with anthracycline drugs was lower than pre-NAC Ki-67(19.6%±23.3%vs.45.6%±23.1%,P<0.001).Furthermore,patients with the Ki-67 decrease had a border line higher pathological complete response(pCR)rate(17.2%vs.0.0%,P=0.068),and a higher overall response rate(ORR)(73.6%vs.27.8%,P<0.001),when compared to patients without the Ki-67 decrease.The ΔKi-67 and ΔKi-67%were valuable markers for the prediction of both the pCR rate and ORR.The area under the curve(AUC)for ΔKi-67 on pCR and ORR was 0.809(0.698-0.921)and 0.755(0.655-0.855),respectively,while the AUC for ΔKi-67% on pCR and ORR was 0.857(0.742-0.972)and 0.720(0.618-0.822),respectively.Multivariate logistic regression model 1 revealed thatΔKi-67 was an independent predictor for both pCR[odds ratio(OR)=61.030,95% confidence interval(CI)=4.709-790.965;P=0.002]and ORR(OR=10.001,95%CI:3.044-32.858;P<0.001).Multivariate logistic regression model 2 revealed thatΔKi-67%was also an independent predictor for both pCR(OR=408.922,95%CI=8.908-18771.224;P=0.002)and ORR(OR=5.419,95%CI=1.842-15.943;P=0.002).Conclusions The present study results suggest thatΔKi67 andΔKi67%are candidate predictors for anthracycline-containing NAC response,and

关键词： breast cancer change in Ki-67 neoadjuvant chemotherapy anthracycline,response

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Effect of low-degree astigmatism on the objective visual quality

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International Journal of Ophthalmology(English edition) 2024年第6期17卷 1086-1093页

作者： Ling-Ying ye shu-Feng Li Jing-Jing Zuo Jin Li Hui-Xiang Ma National Clinical Research Center for Ocular Diseases Eye HospitalWenzhou Medical UniversityWenzhou 325027Zhejiang ProvinceChina

AIM:To evaluate the effect of low-degree astigmatism on objective visual quality through the Optical Quality Analysis System(OQAS).METHODS:This study enrolled 46 participants(aged 23 to 30y,90 eyes)with normal or corrected-to-normal vision.The cylindrical lenses(0,0.5,0.75,1.0,and 1.25 D)were placed at the axial direction(180°,45°,90°,and 135°)in front of the eyes with the best correction to form 16 types of regular low-degree astigmatism.OQAS was used to detect the objective visual quality,recorded as the objective scattering index(OSI),OQAS values at contrasts of 100%,20%,and 9%predictive visual acuity(OV100%,OV20%,and OV9%),modulation transfer function cut-off(MTFcut-off)and Strehl ratio(SR).The mixed effect linear model was used to compare objective visual quality differences between groups and examine associations between astigmatic magnitude and objective visual quality parameters.RESULTS:Apparent negative relationships between the magnitude of low astigmatism and objective visual quality were observed.The increase of OSI per degree of astigmatism at 180°,45°,90°,and 135°axis were 0.38(95%CI:0.35,0.42),0.50(95%CI:0.46,0.53),0.49(95%CI:0.45,0.54)and 0.37(95%CI:0.34,0.41),respectively.The decrease of MTFcut-off per degree of astigmatism at 180°,45°,90°,and 135°axis were-10.30(95%CI:-11.43,-9.16),-12.73(95%CI:-13.62,-11.86),-12.75(95%CI:-13.79,-11.70),and-9.97(95%CI:-10.92,-9.03),respectively.At the same astigmatism degree,OSI at 45°and 90°axis were higher than that at 0°and 135°axis,while MTFcut-off were lower.CONCLUSION:Low astigmatism of only 0.50 D can significantly reduce the objective visual quality.

关键词： low-degree astigmatism objective visual quality Optical Quality Analysis System

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T2-weighted imaging-based radiomic-clinical machine learning model for predicting the differentiation of colorectal adenocarcinoma

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World Journal of Gastrointestinal Oncology 2024年第3期16卷 819-832页

作者： Hui-Da Zheng Qiao-Yi Huang Qi-Ming Huang Xiao-Ting Ke Kai ye shu Lin Jian-Hua Xu Department of Gastrointestinal Surgery The Second Affiliated Hospital of Fujian Medical UniversityQuanzhou 362000Fujian ProvinceChina Department of Gynaecology and Obstetrics The Second Affiliated Hospital of Fujian Medical UniversityQuanzhou 362000Fujian ProvinceChina Department of Computed Tomography/Magnetic Resonance Imaging The Second Affiliated Hospital of Fujian Medical UniversityQuanzhou 362000Fujian ProvinceChina Centre of Neurological and Metabolic Research The Second Affiliated Hospital of Fujian Medical UniversityQuanzhou 362000Fujian ProvinceChina Group of Neuroendocrinology Garvan Institute of Medical ResearchSydneyNSW 2010Australia

BACKGROUND The study on predicting the differentiation grade of colorectal cancer(CRC)based on magnetic resonance imaging(MRI)has not been reported yet.Developing a non-invasive model to predict the differentiation grade of CRC is of great value.AIM To develop and validate machine learning-based models for predicting the differ-entiation grade of CRC based on T2-weighted images(T2WI).METHODS We retrospectively collected the preoperative imaging and clinical data of 315 patients with CRC who underwent surgery from March 2018 to July 2023.Patients were randomly assigned to a training cohort(n=220)or a validation cohort(n=95)at a 7:3 ratio.Lesions were delineated layer by layer on high-resolution T2WI.Least absolute shrinkage and selection operator regression was applied to screen for radiomic features.Radiomics and clinical models were constructed using the multilayer perceptron(MLP)algorithm.These radiomic features and clinically relevant variables(selected based on a significance level of P<0.05 in the training set)were used to construct radiomics-clinical models.The performance of the three models(clinical,radiomic,and radiomic-clinical model)were evaluated using the area under the curve(AUC),calibration curve and decision curve analysis(DCA).RESULTS After feature selection,eight radiomic features were retained from the initial 1781 features to construct the radiomic model.Eight different classifiers,including logistic regression,support vector machine,k-nearest neighbours,random forest,extreme trees,extreme gradient boosting,light gradient boosting machine,and MLP,were used to construct the model,with MLP demonstrating the best diagnostic performance.The AUC of the radiomic-clinical model was 0.862(95%CI:0.796-0.927)in the training cohort and 0.761(95%CI:0.635-0.887)in the validation cohort.The AUC for the radiomic model was 0.796(95%CI:0.723-0.869)in the training cohort and 0.735(95%CI:0.604-0.866)in the validation cohort.The clinical model achieved an AUC of 0.751(95%CI:0.661-0.842)in the training cohort and

关键词： Radiomics Colorectal cancer Differentiation grade Machine learning T2-weighted imaging

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Experimental Study on Vortex-Induced Vibration of Rough Risers with Coupling Interference Effect Under Side-by-Side Arrangement

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China Ocean Engineering 2024年第1期38卷 18-28页

作者： HU Ze-bo LIU Zhen LI Peng GUO Hai-yan WANG shu-bing REN Xiao-hui HOU Hao WANG ye-shuo College of Civil Engineering and Architecture Shandong University of Science and TechnologyQingdao 266590China Qingdao Key Laboratory of Marine Civil Engineering Materials and Structures Qingdao 266590China College of Engineering Ocean University of ChinaQingdao 266100China CHEC Dredging Co. LtdShanghai 200136China

A vortex-induced vibration(VIV)experiment of rough risers with coupling interference effect under a side-by-side arrangement was carried out in a wave-current combined flume.The roughness of the riser was characterized by arranging different specifications of surface attachments on the surface of the riser.Rough risers with three different roughnesses were arranged side by side with smooth risers to explore the VIV response of the riser under the combined action of roughness and interference effect,and to reveal the coupling mechanism between roughness and interference effect.The experimental results show that,compared with that of a smooth riser,the VIV of a rough riser under the coupling interference effect has a wider"lock-in"region,and the displacement decreases more significantly at a high reduced velocity,which is more likely to excite higher-order modes and frequency responses.In addition,the displacement response and frequency response of the smooth riser are not significantly affected by wake interference from the rough riser,which is caused by the decrease of the wake region due to the delay of the boundary layer separation point of the rough riser.

关键词： marine riser vortex-induced vibration side-by-side arrangement roughness interference effect

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Commentary:Mammokine directs beige adipocytes to reserve energy for milk production in breast

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Acta Pharmaceutica Sinica B 2024年第3期14卷 1472-1476页

作者： Lina Tang Jianping ye Metabolic Disease Research Center Zhengzhou University Affiliated Zhengzhou Central HospitalZhengzhou 450007China Research Center for Basic Medicine Academy of Medical SciencesZhengzhou UniversityZhengzhou 450052China

Beige/brown adipocytes play a crucial role in regulating the body’s overall energy balance.The thermogenic function is under the influence of various tissues,including the brain,muscles,and liver.However,the breast t... 详细信息

关键词： Beige Breast Epitheliail cells scRNA-seq Thermogenesis

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Severe pediatric COVID‑19:a review from the clinical and immunopathophysiological perspectives

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World Journal of Pediatrics 2024年第4期20卷 307-324页

作者： Yi‑Kan Sun Can Wang Pei‑Quan Lin Lei Hu Jing ye Zhi‑Gang Gao Ru Lin Hao‑Min Li Qiang shu Li‑Su Huang Lin‑Hua Tan Children's Hospital Zhejiang University School f MedicineHangzhou 310052China The Second Affiliated Hospital Zhejiang University School of MedicineHangzhou 310030China Surgical Intensive Care Unit Children’s HospitalZhejiang University School of MedicineHangzhou 310052China Department of General Surgery Children’s HospitalZhejiang University School of MedicineHangzhou 310052China Department of Cardiopulmonary and Extracorporeal Life Support Children’s HospitalZhejiang University School of MedicineHangzhou 310052China Clinical Data Center Children’s HospitalZhejiang University School of MedicineHangzhou 310052China Department of Cardiac Surgery Children’s HospitalZhejiang University School of MedicineHangzhou 310052China National Clinical Research Center for Child Health Children’s HospitalZhejiang University School of MedicineHangzhou 310052China Department of Infectious Diseases Children’s HospitalZhejiang University School of MedicineHangzhou 310052China

Background Coronavirus disease 2019(COVID-19)tends to have mild presentations in children.However,severe and critical cases do arise in the pediatric population with debilitating systemic impacts and can be fatal at times,meriting further attention from clinicians.Meanwhile,the intricate interactions between the pathogen virulence factors and host defense mechanisms are believed to play indispensable roles in severe COVID-19 pathophysiology but remain incompletely understood.Data sources A comprehensive literature review was conducted for pertinent publications by reviewers independently using the PubMed,Embase,and Wanfang databases.Searched keywords included“COVID-19 in children”,“severe pediatric COVID-19”,and“critical illness in children with COVID-19”.Results Risks of developing severe COVID-19 in children escalate with increasing numbers of co-morbidities and an unvaccinated status.Acute respiratory distress stress and necrotizing pneumonia are prominent pulmonary manifestations,while various forms of cardiovascular and neurological involvement may also be seen.Multiple immunological processes are implicated in the host response to COVID-19 including the type I interferon and inflammasome pathways,whose dysregulation in severe and critical diseases translates into adverse clinical manifestations.Multisystem inflammatory syndrome in children(MIS-C),a potentially life-threatening immune-mediated condition chronologically associated with COVID-19 exposure,denotes another scientific and clinical conundrum that exemplifies the complexity of pediatric immunity.Despite the considerable dissimilarities between the pediatric and adult immune systems,clinical trials dedicated to children are lacking and current management recommendations are largely adapted from adult guidelines.Conclusions Severe pediatric COVID-19 can affect multiple organ systems.The dysregulated immune pathways in severe COVID-19 shape the disease course,epitomize the vast functional diversity of the pediatric immune system and highlight the immun

关键词： Immunopathophysiology MIS-C Pediatric critical care Severe pediatric COVID-19

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