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Assessment of volumetric bone mineral density of the femoral neck in postmenopausal women with and without vertebral fractures using quantitative multi-slice CT

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2009年第7期10卷 499-504页

作者： Sheng-yong WU Hui-hui JIA Didier HANS jing LAN li-ying WANG jing-xue li Yue-zeng CAI Department of Radiology Tianjin First Central Hospital Tianjin 300192 China Department of Radiology General Hospital of Tianjin Medical University Tianjin 300052 China Center of Bone Diseases Department of Bone and Joint Lausanne University Hospital 1011 Lausanne Switzerland

Objective： To demonstrate the validity and reliability of volumetric quantitative computed tomography （vQCT） with multi-slice computed tomography （MSCT） and dual energy X-ray absorptiometry （DXA） for hip bone mineral density （BMD） measurements, and to compare the differences between the two techniques in discriminating postmenopausal women with osteoporosis-related vertebral fractures from those without. Methods： Ninety subjects were enrolled and divided into three groups based on the BMD values of the lumbar spine and/or the femoral neck by DXA. Groups 1 and 2 consisted of postmenopausal women with BMD changes 〈-2SD, with and without radiographically confirmed vertebral fracture （n= 11 and 33, respectively）. Group 3 comprised normal controls with BMD changes 〉-ISD （n-46）. Post-MSCT （GE, lightSpeed16） scan reconstructed images of the abdominal-pelvic region, 1.25 mm thick per slice, were processed by OsteoCAD software to calculate the following parameters： volumetric BMD values of trabecular bone （TRAB）, cortical bone （CORT）, and integral bone （INTGL） of the left femoral neck, femoral neck axis length （NAL）, and minimum cross-section area （mCSA）. DXA BMD measurements of the lumbar spine （AP-SPINE） and the left femoral neck （NECK） also were performed for each subject. Results： The values of all seven parameters were significantly lower in subjects of Groups 1 and 2 than in normal postmenopausal women （P〈0.05, respectively）. Comparing Groups 1 and 2, 3D-TRAB and 3D-INTGL were significantly lower in postmenopausal women with vertebral fracture（s） [（109.8±9.61） and （243.3±33.0） mg/cm^3, respectively] than in those without [（148.9±7.47） and （285.4±17.8） mg/cm^3, respectively] （P〈0.05, respectively）, but no significant differences were evident in AP-SPINE or NECK BMD. Conclusion： the femoral neck-derived volumetric BMD parameters using vQCT appeared better than the DXA-derived ones in discriminating osteoporotic postmenopausal women with vertebral fractures from those wit

关键词： Osteoporosis Bone mineral density (BMD) Volumetric QCT Hip fracture Postmenopausal women

Molecular-scale controllable conversion of biopolymers into hard carbons towards lithium and sodium ion batteries: A review

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Journal of Energy Chemistry 2022年第9期31卷 554-569,I0016页

作者： li-jing Xie Cheng Tang Ming-Xin Song Xiao-Qian Guo Xiao-Ming li jing-xue li Chong Yan Qing-Qiang Kong Guo-Hua Sun Qiang Zhang Fang-Yuan Su Cheng-Meng Chen CAS Key Laboratory of Carbon Materials Institute of Coal ChemistryChinese Academy of SciencesTaiyuan 030001ShanxiChina University of Chinese Academy of Sciences Beijing 100049China Bejing KeyLaboratory of Green Chemical Reaction Engineering and Technology.Department of Chemical Engineering.Tsinghua University Bejing 100084China School o Chemical Enginering and Advanced Materials The Universityof Adelaide.AdelaideSA 5005Ausralia Center of Biomass Enginering/Cllge of Agronomy and Biotechnology China Agriultural UniversiyBeijing 100193China

Hard carbons are widely investigated as potential anodes for lithium and sodium ion batteries owing to their internally well-tailored textures(closed pores and defects) and large microcrystalline interlayer spacing. The renewable biomass is a green and economically attractive carbon source to produce hard carbons. However, the chemical and structural complexity of biomass has plagued the understanding of evolution mechanism from organic precursors to hard carbons and the structure-property *** makes it difficult to finely tune the microstructure of biomass-derived hard carbons, thus greatly restricting their high-performance applications. Most recently, the optimal utilization and controllable conversion of biomass-derived biopolymers(such as starch, cellulose and lignin) at the molecular level have become a burgeoning area of research to develop hard carbons for advanced *** the principal source of carbonaceous materials is from biomass pyrolysis, we firstly overview the chemical structures and pyrolysis behaviors of three main biopolymers. Then, the controllable preparation of hard carbons using various physicochemical properties of biopolymers at the molecular level is systematically discussed. Furthermore, we highlight present challenges and further opportunities in this field. The Review will guide future research works on the design of sustainable hard carbons and the optimization of battery performance.

关键词： Biomass-derived biopolymers Hard carbons lithium ion batteries Sodium ion batteries Carbonization

Exploration of nurses ’ experience in clinical application of stroke nursing scheme based on PARIHS framework

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Nursing Communications 2022年第1期6卷 167-172页

作者： xue-jing li Hong Chen Nursing College of Beijing University of Traditional Chinese Medicine Beijing 102488China Department of Surgery II Breast Dongfang Hospital of Beijing University of Chinese MedicineBeijing 100078China

Objective: Based on evidence-based thinking, a qualitative research method was used to analyze the clinical application status of the traditional Chinese medicine nursing program to provide scientific references for its optimization. Methods: Based on the three elements of the PARIHS framework, combined with clinical investigation, the interview outline was determined to interview the users and promoters of the program. After transcribing and coding the collected data with Nvivo software, referring to Colaizzi ’ s seven-step analysis and generic analysis, all codes are classified and integrated with the core elements and specific connotations of the PARIHS framework to form a theme. Results: The interviewees thought that although the program promoted the development of traditional Chinese medicine nursing to a certain extent, the content lacked scientific research evidence support, and some contents were inconsistent with clinical scenarios and past experience, and the implementation method was rigid, and the effect evaluation was unreasonable. There were 11 themes in three categories. Conclusion: Specific operation processes and scientific research evidence should be added to the scheme, and it should be improved according to clinical practice.

关键词： traditional Chinese medicine nursing program PARIHS framework evidence-based nursing qualitative research

Advancements in endoscopic hemostasis for non-variceal upper gastrointestinal bleeding

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World Journal of Gastrointestinal Endoscopy 2024年第7期16卷 376-384页

作者： xue jing li Brian M Fung Department of Gastroenterology and Hepatology Banner-University Medical Center PhoenixPhoenixAZ 85006United States

Non-variceal upper gastrointestinal(GI)bleeding is a significant cause of morbidity and ***,through-the-scope(TTS)clips,thermal therapy,and injection therapies are used to treat GI *** this review,we provide an overview of novel endoscopic treatments that can be used to achieve ***,we discuss the efficacy and applicability of over-thescope clips,hemostatic agents,TTS doppler ultrasound,and endoscopic ultrasound,each of which offer an effective method of reducing rates of GI rebleeding.

关键词： Doppler probe Endoscopic ultrasound Endoscopy techniques Gastrointestinal bleeding Hemospray Hemostasis Hemostatic agents Over-the-scope clips Ovesco

Polypropylene-based blend with enhanced breakdown strength under gamma-ray irradiation for cable insulation

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Nuclear Science and Techniques 2025年第1期36卷 35-48页

作者： Bai-Xin liu Yu Gao jing li Chen-Yi Guo Bo-Sen Si Jun-Guo Gao Yu Chen Bo-xue Du School of Electrical and Information Engineering Tianjin UniversityTianjin 300072China Key Laboratory of Engineering Dielectrics and Its Application Ministry of EducationHarbin University of Science and TechnologyHarbin 150080China State Key Laboratory of Electrical Insulation and Power Equipment Xi’an Jiaotong UniversityXi’an 710049China

This study focuses on the electrical properties and microstructure of polypropylene(PP)-based blends used for cable insulation in nuclear power plants(NPPs).The PP-based blend,comprising isotactic PP and propylene-based elastomer(PBE)at concentrations ranging from 0 to 50 wt%,underwent a melt blending process and subsequent cobalt-60 gamma-ray irradiation with doses ranging from 0 to 250 *** conductivity,trap distribution,and alternating(AC)breakdown strength were chosen to assess the insulation *** results indicate that the addition of PBE significantly improves the electrical properties of PP under *** PP,the electrical conductivity increased with irradiation,whereas the trap depth and breakdown strength decreased ***,for the blend,these changes initially exhibit opposite *** the irradiation was increased to 250 kGy,the AC breakdown strength of the blend improved by more than 21%compared to that of *** physical and chemical structures of the samples were investigated to explore the improvement *** results offer insights into the design of new cable-insulation materials suitable for NPPs.

关键词： Nuclear power plant Cable insulation Polypropylene Electrical properties Gamma-ray irradiation

The complex roles of m^(6)A modifications in neural stem cell proliferation, differentiation, and self-renewal and implications for memory and neurodegenerative diseases

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Neural Regeneration Research 2025年第6期20卷 1582-1598页

作者： Yanxi li jing xue Yuejia Ma Ke Ye xue Zhao Fangliang Ge Feifei Zheng Lulu liu Xu Gao Dayong Wang Qing Xia Department of Biochemistry and Molecular Biology College of Basic Medical SciencesHarbin Medical UniversityHarbinHeilongjiang ProvinceChina College of Basic Medical Sciences Harbin Medical UniversityHarbinHeilongjiang ProvinceChina Basic Medical Institute Heilongjiang Academy of Medical SciencesHarbinHeilongjiang ProvinceChina Key Laboratory of Heilongjiang Province for Genetically Modified Animals Harbin Medical UniversityHarbinHeilongjiang ProvinceChina Translational Medicine Research and Cooperation Center of Northern China Heilongjiang Academy of Medical SciencesHarbinHeilongjiang ProvinceChina Dongzhimen Hospital Beijing University of Chinese MedicineBeijingChina

N6-methyladenosine(m^(6)A), the most prevalent and conserved RNA modification in eukaryotic cells, profoundly influences virtually all aspects of mRNA metabolism. mRNA plays crucial roles in neural stem cell genesis and neural regeneration, where it is highly concentrated and actively involved in these processes. Changes in m^(6)A modification levels and the expression levels of related enzymatic proteins can lead to neurological dysfunction and contribute to the development of neurological diseases. Furthermore, the proliferation and differentiation of neural stem cells, as well as nerve regeneration, are intimately linked to memory function and neurodegenerative diseases. This paper presents a comprehensive review of the roles of m^(6)A in neural stem cell proliferation, differentiation, and self-renewal, as well as its implications in memory and neurodegenerative diseases. m^(6)A has demonstrated divergent effects on the proliferation and differentiation of neural stem cells. These observed contradictions may arise from the time-specific nature of m^(6)A and its differential impact on neural stem cells across various stages of development. Similarly, the diverse effects of m^(6)A on distinct types of memory could be attributed to the involvement of specific brain regions in memory formation and recall. Inconsistencies in m^(6)A levels across different models of neurodegenerative disease, particularly Alzheimer's disease and Parkinson's disease, suggest that these disparities are linked to variations in the affected brain regions. Notably, the opposing changes in m^(6)A levels observed in Parkinson's disease models exposed to manganese compared to normal Parkinson's disease models further underscore the complexity of m^(6)A's role in neurodegenerative processes. The roles of m^(6)A in neural stem cell proliferation, differentiation, and self-renewal, and its implications in memory and neurodegenerative diseases, appear contradictory. These inconsistencies may be a

关键词： Alzheimer's disease cell self-renewal central nervous system memory microglia nerve regeneration neurodegenerative diseases neurogenesis RNA methylation

Preparation and performance of highly-conductive dual-doped li_(7)La_(3)Zr_(2)O_(12)solid electrolytes for thermal batteries

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Green Energy & Environment 2025年第2期10卷 399-409页

作者： Wei li Shu Zhang Xinya Bu jing Luo Yi Zhang Mengyu Yan Ting Quan Yanli Zhu State Key Laboratory of Explosion Science and Safety Protection Beijing Institute of TechnologyBeijing100081China Xi'an North Qinghua Electromechanical Co. Ltd.Xi'an710025China Beijing Institute of Technology Chongqing Innovation Center Chongqing401120China

Garnet li_(7)La_(3)Zr_(2)O_(12)(LLZO)electrolytes have been recognized as a promising candidate to replace liquid/molten-state electrolytes in battery applications due to their exceptional performance,particularly Ga-doped LLZO(LLZGO),which exhibits high ionic ***,the limited size of the liþtransport bottleneck restricts its high-current discharging *** present study focuses on the synthesis of Ga^(3+)þand Ba^(2+)þco-doped LLZO(LLZGBO)and investigates the influence of doping contents on the morphology,crystal structure,liþtransport bottleneck size,and ionic *** particular,Ga_(0.32)Ba_(0.15)exhibits the highest ionic conductivity(6.11E-2 S cm^(-1) at 550 C)in comparison with other compositions,which can be attributed to its higher-energy morphology,larger bottleneck and unique liþtransport *** addition to Ba^(2+),Sr^(2+)þand Ca^(2+)have been co-doped with Ga3þinto LLZO,respectively,to study the effect of doping ion radius on crystal structures and the properties of *** characterization results demonstrate that the easier liþtransport and higher ionic conductivity can be obtained when the electrolyte is doped with larger-radius *** a result,the assembled thermal battery with Ga_(0.32)Ba_(0.15)-LLZO electrolyte exhibits a remarkable voltage platform of 1.81 V and a high specific capacity of 455.65 mA h g^(-1) at an elevated temperature of 525℃.The discharge specific capacity of the thermal cell at 500 mA amounts to 63%of that at 100 mA,showcasing exceptional high-current discharging *** assembled as prototypes with fourteen single cells connected in series,the thermal batteries deliver an activation time of 38 ms and a discharge time of 32 s with the current density of 100 mA cm^(-2).These findings suggest that Ga,Ba co-doped LLZO solid-state electrolytes with high ionic conductivities holds great potential for high-capacity,quick-initiating and high-current discharging thermal batteries.

关键词： Element doping Thermal battery Solid electrolyte LLZO Ionic conductivity

Catalytic production of high-energy-density spiro polycyclic jet fuel with biomass derivatives

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Journal of Energy Chemistry 2025年第2期101卷 760-768页

作者： Wen-jing Zhang Yan-Cheng Hu Yan-Hong Tan Jia li Ning li jing-Pei Cao School of Chemical Engineering and Technology China University of Mining and Technology CAS Key Laboratory of Science and Technology on Applied Catalysis Dalian Institute of Chemical Physics Chinese Academy of Sciences

High-energy-density（HED） fuel（*** used JP-10 and RJ-4）,featuring compact 3D polycyclic structure with high strain,is of critical importance for volume-limited military aircraft,since their high density and combustion heat can provide more propulsion *** reduce the reliance on petroleum source,it is highly desirable to develop renewable alternatives for the production of strained polycyclic HED fuel,but which remains a big challenge because of the inaccessibility caused by the high strain,We herein demonstrate a three-step catalytic route towards highly strained C17and C18spirofuel with biomass *** process includes catalytic aldol condensation of renewable cyclohexanone/cyclopentanone with benzaldehyde,catalytic spiro Diels-Alder（D-A） reaction of aldol adduct with isoprene,and catalytic *** key spiro D-A reaction is enabled by the catalysis of heterogeneous Lewis acidic ionic *** chloroaluminate IL,formed by benign urea and AICl3,exhibits good catalytic performance and reusability for this *** eventual hydrodeoxygenation（HDO）over Pd/C and H-Y produces strained tricyclic spirofuel with density>0.93 g/mL,combustion heat>41 MJ/L and freezing point <-40℃,which are better than the properties of tactical fuel ***,it is anticipated that the as-prepared renewable fuels have the potential to replace traditional petroleum-derived HED fuels.

关键词： Biomass derivatives Cycloaddition High-energy-density Lewis acidic ionic liquid Spiro polycyclic fuel

Targeting cholesterol trafficking to mitigate axonal degeneration in hereditary spastic paraplegia

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Neural Regeneration Research 2025年第5期20卷 1397-1398页

作者： Zhenyu Chen xue-Jun li Department of Biomedical Sciences University of Illinois College of Medicine RockfordRockfordILUSA Department of Bioengineering University of Illinois at ChicagoChicagoILUSA

Axonal degeneration underlies many debilitating diseases including hereditary spastic paraplegia(HSP),a genetically and clinically diverse group of disorders characterized by spasticity and weakness of the lower *** is one significant cause of chronic neurodisability due to the lack of effective treatments and a wide range of onset ages from early childhood to 70 years.

关键词： degeneration diseases hereditary