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Thermal stability of permafrost under U-shaped crushed rock embankment of the Qinghai-Tibet Railway

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Advances in Climate Change Research 2024年第1期15卷 158-169页

作者： Kun-Ming XU Guan-Li jiANG ji chen Qing-Bai WU State Key Laboratory of Frozen Soil Engineering Northwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhou 730000China University of Chinese Academy of Sciences Beijing 100049China Beiluhe Observation Station of Frozen Soil Environment and Engineering Northwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhou730000China

The U-shaped crushed rock embankment(UCRE),of which widely utilized in the permafrost regions along the Qinghai-Tibet Railway,has the capability to rapidly reduce the ground temperature of the underlying permafrost.However,there remains uncertainty regarding the adaptation of UCRE to climate change and its long-term cooling trend.This study focuses on nine UCRE monitoring sites along the Qinghai-Tibet Railway to analyze the dynamic variations of the ground temperature underlying permafrost from 2006 to 2020.The efficiency of UCRE in stabilizing permafrost temperature in different permafrost zones is evaluated by considering the permafrost table,ground temperature,and MAGT,as well as the temperature difference between the top and bottom of the crushed rock layer and the ground temperature variation index(GTVI).The results show that UCRE is suitable for application in extremely unstable warm permafrost regions where the MAGT is higher than-0.5℃.Moreover,UCRE effectively diminishes the disparity in permafrost thermal stability between the sunny and shaded shoulders of the embankment.The short-term and long-term effect of cooling permafrost is experiencing a change related with permafrost stability.Notably,in stable cold permafrost regions with MAGT lower than-1.5℃,the long-term cooling effect of UCRE on permafrost seems to gradually di-minishes,but UCRE continues to fulfill the role of stabilizing the underlying permafrost thermal state over the long-term.These results show that UCRE can quickly restore and stabilize the thermal state of permafrost in the early stages of construction,and adapt to the influence of future climate change.The findings provide important guidance for understanding the variations of permafrost thermal stability beneath the embankment in permafrost regions,as well as for improving the embankment stability and operational safety of the Qinghai-Tibet Railway.

关键词： Qinghai-Tibet Railway U-shaped crushed rock embankment Climate change Permafrost zone Ground temperature variation index Long-term coolingrole

Relationship between ultrasound parameters of the umbilical and middle cerebral arteries and intrauterine fetal distress

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World Journal of Clinical Cases 2024年第16期12卷 2745-2750页

作者： ji chen Fei-Xue Liu Rui-Xue Tao Department of Obstetrics The Third Affiliated Hospital of Anhui Medical UniversityHefei 230061Anhui ProvinceChina Anhui Medical University First Clinical School of MediumClass 2021Clinical MedicineHefei 230032Anhui ProvinceChina

BACKGROUND By comprehensively analyzing the blood flow parameters of the umbilical and middle cerebral arteries,doctors can more accurately identify fetal intrauterine distress,as well as assess its severity,so that timely interventions can be implemented to safeguard the health and safety of the fetus.AIM To identify the relationship between ultrasound parameters of the umbilical and middle cerebral arteries and intrauterine distress.METHODS Clinical data of pregnant women admitted between January 2021 and January 2023 were collected and divided into the observation and control groups(n=50 each),according to the presence or absence of intrauterine distress.The ultrasound hemodynamic parameters of the uterine artery(UtA),fetal middle cerebral artery(MCA),and umbilical artery(UmA)were compared with neonatal outcomes and occurrence of intrauterine distress in the two groups.RESULTS Comparison of ultrasonic hemodynamic parameters,resistance index(RI),pulsatility index(PI),and systolic maximal blood flow velocity of UmA compared to diastolic blood flow velocity(S/D),revealed higher values of fetal MCA,PI,and S/D of UmA in pregnant women with UtA compared to controls(P<0.05),while there was no difference between the two groups in terms of RI(P<0.05)The incidence of a neonatal Apgar score of 8-10 points was lower in the observation group(66.7%)than in the control group(90.0%),and neonatal weight(2675.5±27.6 g)was lower than in the control group(3117.5±31.2 g).Further,cesarean section rate was higher in the observation group(70.0%)than in the control group(11.7%),and preterm labor rate was higher in the observation group(40.0%)than in the control group(10.0%).The incidence of fetal distress,neonatal growth restriction and neonatal asphyxia were also higher in the observation group(all P<0.05).CONCLUSION Fetal MCA,UmA,and maternal UtA hemodynamic abnormalities all develop in pregnant women with intrauterine distress during late pregnancy,which suggests that clinical attention should be paid to them,and monitoring should

关键词： Late pregnancy Fetal intrauterine distress Ultrasound blood flow parameters Uterine artery Middle cerebral artery Umbilical artery

Degradation of warm permafrost and talik formation on the Qinghai-Tibet Plateau in 2006-2021

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Advances in Climate Change Research 2024年第2期15卷 275-284页

作者： Qi-Hang MEI ji chen You-Qian LIU Shou-Hong ZHANG jing-Yi ZHAO Tian-Chun DONG Jun-cheng WANG Yao-Jun ZHAO Beiluhe Observation and Research Station of Frozen Soil Engineering and Environment Key Laboratory of Cryospheric Science and Frozen Soil EngineeringNorthwest Institute of Eco-Environmental and ResourcesChinese Academy of SciencesLanzhou 730000China China Railway Qinghai-Tibet Group Co.Ltd Xining 810007China University of Chinese Academy of Sciences Beijing 100049China

Permafrost is degrading globally,particularly those with low thermal stability on the Qinghai-Tibet Plateau,owing to climate change.However,the inadequacy of direct research on permafrost degradation based on in-situ monitoring limits the prediction of permafrost degradation and engineering practices.This study explored the processes and modes of permafrost degradation into talik by analyzing ground temperature data from five points in the hinterland of the Qinghai-Tibet Plateau from 2006 to 2021.The results showed that the degradation of the warm permafrost layer with a geothermal gradient of zero occurred simultaneously in the top and bottom directions.The rate of permafrost degradation from the top down and bottom up increase during the degradation process,but the increase of the former is more drastic after the formation of thawed interlayer.Additionally,the construction of the Qinghai-Tibet Railway changed the degradation modes of the permafrost in adjacent natural sites through horizontal heat transfer,particularly after through talik formation under the embankment.The findings suggest that taking countermeasures before or immediately after forming thawed interlayer is more effective.When evaluating the thermal impact of projects in warm permafrost regions,special attention should be given to the horizontal heat transfer process that may result from the formation of a through talik.

关键词： Warm permafrost Degradation Talik Qinghai-Tibet Plateau Climate change

In-situ powder mixing for laser-based directed energy deposition of functionally graded materials

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Advances in Manufacturing 2024年第1期12卷 150-166页

作者： ji-Peng chen Shou-Chun Xie He Huang School of Mechanical and Electronic Engineering Nanjing Forestry UniversityNanjing210037People’s Republic of China Nanjing Huirui Photoelectric Technology Co. LtdNanjing211121People’s Republic of China

The mixing of powders is a highly relevant field under additive manufacturing,however,it has attracted limited interest to date.The in-situ mixing of various powders remains a significant challenge.This paper proposes a new method utilizing a static mixer for the in-situ mixing of multiple powders through the laser-based directed energy deposition(DED)of functionally graded materials.Firstly,a powder-mixing experimental platform was established;WC and 316L powders were selected for the mixing experiments.Secondly,scanning electron microscopy,energy dispersive spectroscopy,and image processing were used to visually evaluate the homogeneity and proportion of the in-situ mixed powder.Furthermore,powder-mixing simulations were conducted to determine the powder-mixing mechanism.In the simulations,a powder carrier gas flow field and particle mixing were employed.Finally,a WC/316L metal matrix composite sample was produced using laser-based DED to verify the application potential of the static mixer.It was found that the static mixer could adjust the powder ratio online,and a response time of 1–2 s should be considered when adjusting the ratio of the mixed powder.A feasible approach for in-situ powder mixing for laser-based DED was demonstrated and investigated,creating the basis for functionally graded materials.

关键词： Laser Deposition Static mixer Powder mixing Functionally graded materials

Research progress toward the influence of mosquito salivary proteins on the transmission of mosquito-borne viruses

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Insect Science 2024年第3期31卷 663-673页

作者： Zhao-Yang Wang Kai-Xiao Nie ji-chen Niu Gong cheng Tsinghua University-Peking University Joint Center for Life Sciences School of MedicineTsinghua UniversityBejingChina Institute of Infectious Diseases Shenzhen Bay LaboratoryShenzhenGuangdongChina Department of Pathogen Biology School of Basic MedicineShandong First Medical University&Shandong Academy of Medical SciencesJinanChina

Mosquito-borne viruses(MBVs)are a large class of viruses transmitted mainly through mosquito bites,including dengue virus,Zika virus,Japanese encephalitis virus,West Nile virus,and chikungunya virus,which pose a major threat to the health of people around the world.With global warming and extended human activities,the incidence of many MBVs has increased significantly.Mosquito saliva contains a variety of bioactive protein components.These not only enable blood feeding but also play a crucial role in regulating local infection at the bite site and the remote dissemination of MBVs as well as in remodeling the innate and adaptive immune responses of host vertebrates.Here,we review the physiological functions of mosquito salivary proteins(MSPs)in detail,the influence and the underlying mechanism of MSPs on the transmission of MBVs,and the current progress and issues that urgently need to be addressed in the research and development of MSP-based MBV transmission blocking vaccines.

关键词： immune response mosquito-borne virus mosquito salivary protein saliva vaccine transmission

Translocation of a fish spike from the pharynx to the thyroid gland:A case report

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World Journal of Clinical Cases 2024年第7期12卷 1365-1370页

作者： Deng Li Wan-Ting Zeng jian-Guo jiang ji-Chuan chen Department of Otolaryngology Head and Neck Surgery Army Medical Center of PLAChongqing 400042China

BACKGROUND A fish spike stuck in the throat is a common ear,nose,and throat(ENT)emergency.However,it is very rare for a fish spike to reach the thyroid tissue through the throat,which is very dangerous and can lead to pharyngeal fistula,cervical abscess,mediastinal abscess,and thyroid abscess.Proper and timely management can help reduce complications,especially in elderly patients.CASE SUMMARY In the case presented here,the causative factor was dentures,but improper management aggravated the condition.In the case presented here,an elderly woman with a history of accidentally swallowing fish bones for 20 d had a sensation of foreign bodies in her throat.Eventually,computed tomography(CT)of the neck showed that the left side of the thyroid gland had a dense shadow in the form of a stripe.CONCLUSION If a fishbone foreign body is not visible during endoscopic examination but the patient has significant symptoms,the surgeon should be aware that the fishbone may be lodged in the thyroid.To avoid a misdiagnosis,ultrasound,CT,and other tests can be used to clarify the diagnosis.T The first step in treating a fish bone in the thyroid gland is to determine the position of the foreign body and the extent of the infection,and to develop a personalized surgical plan for its removal.At the same time,scientific information should be made available to the general public so that people know that if a fish bone is accidentally lodged,they should not force it to be swallowed or be spit out by inducing vomiting,which are incorrect methods and may aggravate the condition or even cause it to migrate outside the cavity,leading to serious complications,as in this reported case.

关键词： Fish spike Thyroid Pharynx Foreign body migration Case report

Advances in the study of gastric organoids as disease models

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World Journal of Gastrointestinal Oncology 2024年第5期16卷 1725-1736页

作者： Yi-Yang Liu De-Kun Wu ji-Bing chen You-Ming Tang Feng jiang Graduate School Guangxi University of Chinese MedicineNanning 530011Guangxi Zhuang Autonomous RegionChina Teaching Experiment and Training Center Guangxi University of Chinese MedicineNanning 530011Guangxi Zhuang Autonomous RegionChina Central Laboratory Ruikang Hospital Affiliated to Guangxi University of Traditional Chinese MedicineNanning 530011Guangxi Zhuang Autonomous RegionChina Department of Digestive Disease Ruikang Hospital Affiliated to Guangxi University of Traditional Chinese MedicineNanning 530011Guangxi Zhuang Autonomous RegionChina AIDS Research Center Ruikang Hospital Affiliated to Guangxi University of Traditional Chinese MedicineNanning 530011Guangxi Zhuang Autonomous RegionChina

Gastric organoids are models created in the laboratory using stem cells and sophisticated three-dimensional cell culture techniques.These models have shown great promise in providing valuable insights into gastric physiology and advanced disease research.This review comprehensively summarizes and analyzes the research advances in culture methods and techniques for adult stem cells and induced pluripotent stem cell-derived organoids,and patient-derived organoids.The potential value of gastric organoids in studying the pathogenesis of stomach-related diseases and facilitating drug screening is initially discussed.The construction of gastric organoids involves several key steps,including cell extraction and culture,three-dimensional structure formation,and functional expression.Simulating the structure and function of the human stomach by disease modeling with gastric organoids provides a platform to study the mechanism of gastric cancer induction by Helicobacter pylori.In addition,in drug screening and development,gastric organoids can be used as a key tool to evaluate drug efficacy and toxicity in preclinical trials.They can also be used for precision medicine according to the specific conditions of patients with gastric cancer,to assess drug resistance,and to predict the possibility of adverse reactions.However,despite the impressive progress in the field of gastric organoids,there are still many unknowns that need to be addressed,especially in the field of regenerative medicine.Meanwhile,the reproducibility and consistency of organoid cultures are major challenges that must be overcome.These challenges have had a significant impact on the development of gastric organoids.Nonetheless,as technology continues to advance,we can foresee more comprehensive research in the construction of gastric organoids.Such research will provide better solutions for the treatment of stomach-related diseases and personalized medicine.

关键词： Organoids Stomach neoplasms Helicobacter pylori Drug evaluation Preclinical Precision

Monothetic and conductive network and mechanical stress releasing layer on micron-silicon anode enabling high-energy solid-state battery

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Rare Metals 2024年第3期43卷 1017-1029页

作者： Xiang Han Min Xu Lan-Hui Gu Chao-Fei Lan Min-Feng chen Jun-jie Lu Bi-Fu Sheng Peng Wang Song-Yan chen ji-Zhang chen College of Materials Science and Engineering Co-Innovation Center of Efficient Processing and Utilization of Forestry ResourcesNanjing Forestry UniversityNanjing210037China Department of Physics Xiamen UniversityXiamen361005China Western Digital Corporation MilpitasCA95035USA

Silicon has ultrahigh capacity,dendrite-free alloy lithiation mechanism and low cost and has been regarded as a promising anode candidate for solid-state battery.Owing to the low infiltration of solid-state electrolyte(SSE),not the unstable solid-electrolyte interphase(SEI),but the huge stress during lithiation-and delithiation-induced particle fracture and conductivity lost tend to be the main issues.In this study,starting with micron-Si,a novel monothetic carbon conductive framework and a MgO coating layer are designed,which serve as electron pathway across the whole electrode and stress releasing layer,respectively.In addition,the in situ reaction between Si and SSE helps to form a LiF-rich and mechanically stable SEI layer.As a result,the mechanical stability and charge transfer kinetics of the uniquely designed Si anode are significantly improved.Consequently,high initial Coulombic efficiency,high capacity and durable cycling stability can be achieved by applying the Si@MgO@C anode in SSB.For example,high specific capacity of 3224.6 mAh·g^(-1)and long cycling durability of 200 cycles are achieved.This work provides a new concept for designing alloy-type anode that combines surface coating on particle and electrode structure design.

关键词： Lithium-ion battery(LIB) Solid-state electrolyte(SSE) Silicon anode Stress relief Coating

Surface engineering of Li-and Mn-rich layered oxides for superior Li-ion battery

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Tungsten 2024年第1期6卷 259-268页

作者： Lu-Xiang Ma Tian-Dong chen Chun-Xi Hai Sheng-De Dong Xin He Qi Xu Hang Feng AXin ji-Tao chen Yuan Zhou College of Materials and Chemistry and Chemical Engineering Chengdu University of TechnologyChendu 610000China Qinghai Building and Materials Research Co. LtdXining 810000China Beijing National Laboratory for Molecular Sciences College of Chemistry and Molecular EngineeringPeking UniversityBeijing 100871China

The Li-and Mn-rich layered oxides(R-LNCM)are considered as promising cathode materials for high-energy density lithium-ion batteries(LIBs).However,the interface side reaction aggravates the voltage and capacity fading between cathode material and electrolyte at high voltage,which severely hinders the practical application of LIB s.Herein,lithium polyacrylate(LiPAA)as the binder and coating agent is applied to suppress the voltage and capacity fading of R-LNCM electrode.The flexible LiPAA layers with high elasticity are capable of impeding cathode cracks on the particle surface via mechanical stress relief.Thus,superior voltage and capacity fading suppression on R-LNCM electrode is finally achieved.As a result,LiPAA-R-LNCM cathode exhibits a remarkable specific capacity of 186 mA·h·g^(-1)with~73%retention at 1℃after 200cycles.Further,the corresponding average discharge potential is maintained to~3.1 V with only~0.4 V falling.

关键词： LiPAA interphase layer Interface side reaction Cathode cracks Capacity and voltage fading suppression Liand Mn-rich cathode