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Development and evaluation of the Directive and Nondirective Support Scale for Patients with Type 2 Diabetes 被引量:1
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作者 Xuxi Zhang Xing Zhang +5 位作者 Fengbin Wang Shiyan Wu Kang Hu Mayinuer Yusufu Xinying Sun Edwin B.Fisher 《International Journal of Nursing Sciences》 CSCD 2020年第4期453-459,I0007,共8页
Objectives:This study aims to develop the Directive and Nondirective Support Scale for Patients with Type 2 Diabetes(DNSS-T2DM)to measure diabetes-specific support and patients’preference as well as evaluate the cons... Objectives:This study aims to develop the Directive and Nondirective Support Scale for Patients with Type 2 Diabetes(DNSS-T2DM)to measure diabetes-specific support and patients’preference as well as evaluate the construct validity and reliability of the DNSS-T2DM.Methods:A cross-sectional study was conducted in Tongzhou District,Beijing,China from July to September 2015.A total of 474 participants who had been diagnosed as type 2 diabetes by physicians and completed the DNSS-T2DM were included.The original 11-item DNSS-T2DM contains five items on nondirective support(Items 1-5)and six items on directive support(Items 6-11).There were two parallel questions for each item with one to measure the preference for support(Preference part)and the other to measure the perception of support in reality(Reality part).The final DNSS-T2DM was determined based on the results of the exploratory factor analysis(EFA).The construct validity of the final DNSS-T2DM was evaluated by the confirmatory factor analysis(CFA).The reliability was evaluated by internal consistency with Cronbach’sαcoefficients.Results:A final 7-item DNSS-T2DM loaded on 2 factors with four items representing nondirective support and three items representing directive support was determined based on the EFA.The CFA indicated a satisfactory construct validity.The internal consistency of the 7-item DNSS-T2DM as well as the nondirective support items was satisfactory with Cronbach’sα≥7.00.70.Conclusions:Our study supported the validity and reliability of the 7-item DNSS-T2DM.Further studies on the application of the DNSS-T2DM in different settings and population are needed. 展开更多
关键词 Diabetes mellitus directive support Nondirective support Patient preference SELF-MANAGEMENT Social support
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European legal framework related to underground mining and tunnelling concerning commission directive (EU) 2017/164, 31 January establishing a fourth list of indicative occupational exposure limit values 被引量:1
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作者 Miguel Tato Diogo 《International Journal of Mining Science and Technology》 SCIE EI CSCD 2020年第4期541-545,共5页
Directive(EU)2017/164 establishes a fourth list of indicative occupational exposure limit values(IOELVs)to protect workers from risks of exposure to hazardous chemicals.It states that in underground mining and tunnell... Directive(EU)2017/164 establishes a fourth list of indicative occupational exposure limit values(IOELVs)to protect workers from risks of exposure to hazardous chemicals.It states that in underground mining and tunnelling,Member States may benefit from a transitional period regarding IOELVs for nitrogen monoxide,nitrogen dioxide,and carbon monoxide,during which the existing established IOELVs may be applied.The European Advisory Committee on Health and Safety at Work questions the technical feasibility of the proposed IOELVs in underground mining(CO,NO and NO2)and tunnelling(NO and NO2).Challenges arise concerning the availability of measurement methodologies for compliance with proposed IOELVs(NO2)in underground mining and tunnelling environments. 展开更多
关键词 Nitrogen monoxide Nitrogen dioxide Carbon monoxide IOELVs European directive 2017/164 Underground mining TUNNELLING
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The Effect of Educational Intervention regarding Advance Care Planning for Advance Directives
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作者 Yae Takeshita Mika Ikeda +1 位作者 Sayaka Sone Michiko Moriyama 《Health》 2015年第8期934-945,共12页
This study aimed to examine the effects of empowerment and education intervention to promote Advance Care Planning (ACP) for residents in a highly aged and depopulated region. The study utilized a single-group pre- an... This study aimed to examine the effects of empowerment and education intervention to promote Advance Care Planning (ACP) for residents in a highly aged and depopulated region. The study utilized a single-group pre- and post-test design and was conducted in Osakikamijima, Hiroshima, Japan. The researchers and town officials together formed an ACP committee and created an intervention framework. An ACP workshop was held for the participants and a self-administered questionnaire was carried out before, immediately after, and 3 months after the workshop. A total of 125 residents participated in the workshop and 87 of them completed more than 80% of the questionnaire items, whose responses were analyzed as valid responses. The number of participants who completed the AD increased significantly three months after the workshop (p = 0.008). There was a slight increase in the frequency of consultation with the family, but no change was observed in terms of consultation with healthcare providers. The educational intervention in-creased the respondents’ awareness and knowledge of ACP but did not affect the autonomous decision-making process regarding end-of-life care. This strategic process of ACP empowered the residents’ awareness and attitude towards end-of-life care with an increased completion rate of AD. On the other hand, cognitive barriers remained toward communication and decision-making shared with healthcare providers. Insufficient consultation with family members also became evident. Therefore, a new intervention strategy which helps increase communication with healthcare providers needs to be formulated and guidelines for consultation with the family and others need to be prepared. 展开更多
关键词 END-OF-LIFE ADVANCE CARE Planning ADVANCE directiveS COMMUNITY EMPOWERMENT
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Habitats of Directive 92/431EEC in the National Park of Alta Murgia (Apulia-Southern Italy): Threat, Action and Relationships with Plant Communities
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作者 Enrico Vito Perrino Robert Philipp Wagensommer 《Journal of Environmental Science and Engineering(A)》 2013年第4期229-235,共7页
The study reports the habitats of Directive 92/43/EEC in National Park of Alta Murgia (Apulia Region, southem Italy). The habitats have been identified based on phytosociological analysis. New records are presented ... The study reports the habitats of Directive 92/43/EEC in National Park of Alta Murgia (Apulia Region, southem Italy). The habitats have been identified based on phytosociological analysis. New records are presented of rocky, meadow, woodlands and temporary ponds habitats, such as: Stipo bromoidis-Quercetum dalechampii (habitat: eastern white oak woods, 91AA*); Verbenion supinae (habitat: Mediterranean temporary ponds, 3170*); Campanulo versicoloris-Dianthion japigici (habitat: calcareous rocky slopes with chasmophytic vegetation, 8210); Acino suaveolentis-Stipetum austroitalicae (habitat: eastern sub-mediterranean dry grasslands (Scorzoneretalia villosae), 62A0). Other information on their extension, major threat and suggestions of actions for their conservation are provided. 展开更多
关键词 Apulia Region (Italy) habitats of directive 92/43/EEC National Park of Alta Murgia plant communities.
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Advance Directives in the Context of Uncertain Prognosis for Residents of Nursing Homes
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作者 Beryl E. Cable-Williams Donna M. Donna M. Wilson Norah Keating 《Open Journal of Nursing》 2014年第4期321-329,共9页
This report documents the findings of a mixed-methods study focused on the advanced directives of 182 residents of three LTC facilities in southern Ontario, Canada. Although almost all had a completed advance directiv... This report documents the findings of a mixed-methods study focused on the advanced directives of 182 residents of three LTC facilities in southern Ontario, Canada. Although almost all had a completed advance directive within 3 months of death, most did not have a palliative designation or directive until a few days before they died. Each facility’s written Progress Notes revealed staff members usually sought additional confirmation of care preferences from residents’ substitute decision-makers within a few days of the death. It was thus common for advance directives to change from a more interventionist approach to the least interventionist approach near death. This change indicates that the meaning and significance of advance care planning and resulting advance directives must be considered in light of the processes and temporal factors involved in their completion and use within this distinct population. The relational nature of advance care planning and concern about ageism as a factor for withholding or withdrawing life support for LTC residents are considered as possible explanatory factors. These findings and their implications are described in relation to end-of-life care policies and practices in LTC facilities. 展开更多
关键词 ADVANCE CARE Planning ADVANCE directiveS PALLIATIVE CARE Nursing HOMES
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Preliminary Considerations About the Transposition of Directive 2013/34/EU Into Italian Accounting System
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作者 Roberta Provasi Claudio Sottoriva 《Journal of Modern Accounting and Auditing》 2015年第6期302-312,共11页
With the Directive No. 2013/34/EU dated June 26, 2013, the Parliament and the European Council have decreed a new era for the financial statements of companies in the EU member countries. The introduction of the new d... With the Directive No. 2013/34/EU dated June 26, 2013, the Parliament and the European Council have decreed a new era for the financial statements of companies in the EU member countries. The introduction of the new directive aims to improve the coverage information of the accounting document and to begin a process of simplification of administrative burdens and standards for the preparation and publication of the financial statements. In Italy, the directive must be transposed by July 20, 2015 for which the associations of accountants are evaluating the specific contents of the new rules to make applications for Italian companies. Some of the new rules and above all part of the new structures of the schemes of the financial statements are quite different from the approaches currently in use for which very heated discussions are taking place. 展开更多
关键词 European directive 2013/34/EU Italian accounting system accounting harmonization
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Renewable Diesel Fuel from Processing of Vegetable Oil in Hydrotreatment Units: Theoretical Compliance with European Directive 2009/28/EC and Ongoing Projects in Spain
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作者 Daniel Garraín Israel Herrera +2 位作者 Carmen Lago Yolanda Lechón Rosa Sáez 《Smart Grid and Renewable Energy》 2010年第2期70-73,共4页
Oil hydrotreating units in refineries are aimed at reducing the sulfur content of fuels to accomplish standard par-ticular specifications. However, this process is currently one of the best available technologies to p... Oil hydrotreating units in refineries are aimed at reducing the sulfur content of fuels to accomplish standard par-ticular specifications. However, this process is currently one of the best available technologies to produce biofuels from vegetable oil in a refinery. Vegetable oils can be processed or co-processed in these units if several adaptations are performed, so some properties could be improved in comparison with conventional fuel such as density and cetane number. This study highlights the theoretical greenhouse gases (GHG) emissions (using a life cycle assessment–LCA-approach) of a hydrotreated vegetable oil (HVO) from bibliographical data. Results were compared with other biofuel production processes, such as those obtained by transesterification of vegetable oil (FAME, fatty acid methyl ester). It has also been included the comparison with conventional fossil diesel as a benchmark in order to assess the theoretical compliance with GHG savings proposed in European Directive 2009/28/EC. Finally, ongoing projects and future perspectives in Spain are mentioned. 展开更多
关键词 Hydrotreated VEGETABLE Oil FATTY Acid Methyl ESTER GHG Emissions SAVINGS directive 2009/28/EC RENEWABLE Diesel Fuel
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Directives and references in selected coronavirus-motivated internet memes
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作者 Ayo Osisanwo Toluwalope Mary Falade 《Language and Semiotic Studies》 2024年第2期245-266,共22页
The use of directives in communicating the nature of the pandemic and reference to social experiences were promoted using images on social media platforms.The images or memes are used to create awareness and reinforce... The use of directives in communicating the nature of the pandemic and reference to social experiences were promoted using images on social media platforms.The images or memes are used to create awareness and reinforce the criteria for safety during the pandemic.Previous studies on internet memes have concentrated on humor generation,speaker-hearer shared knowledge,neologism,and multimodality among others,with insufficient attention paid to the use of directives and references in such coronavirus-motivated memes.This paper,therefore,examines how directives and references are employed in conveying expected social responsibilities through coronavirus-motivated internet memes in Nigeria and other socio-cultural contexts.For data,one hundred coronavirus-motivated memes were purposively selected from Facebook,and eight representative memes were subjected to pragmatic analysis using aspects of Jacob Mey’s(2001.Pragmatics:An introduction,2nd edn.USA:Blackwell Publishing)pragmatic acts theory to unearth insights from them.The paper observes that the various spheres of life that are relatable to an online audience help to express what the pandemic is about and enhance the meaning of the pandemic with the context of the use of the memes,giving clearer perspectives on the pandemic.Directives and references are useful tools for conveying social responsibilities to online audience. 展开更多
关键词 directiveS REFERENCES CORONAVIRUS internet memes social responsibilities
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Superdirective Circular Arrays of Electric and Huygens Dipole Elements
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作者 Richard W.Ziokowski 《Electromagnetic Science》 2024年第1期38-62,共25页
Uniform circular arrays(UCAs)provide both omnidirectional(360°)and directive(sector)coverage of the azimuthal plane.Superdirective versions with unidirectional,high front-to-back ratio(FTBR)properties could provi... Uniform circular arrays(UCAs)provide both omnidirectional(360°)and directive(sector)coverage of the azimuthal plane.Superdirective versions with unidirectional,high front-to-back ratio(FTBR)properties could provide the radiated field char-acteristics being pursued for NextG wireless networks and their perceived applications.Typical UCA configurations–full,semi-circular,and sector–that radiate vertically-polarized(VP)fields and are composed of either omnidirectional electric dipole ele-ments or unidirectional Huygens dipole elements are analyzed first with conventional methods as reference cases.These omni-and uni-directional element configurations are then treated with several optimization techniques:the classic Rayleigh-quotient(RQ)method and its unidirectional-constrained version;the eigenbeam decomposition and synthesis(EBDS)technique used to design su-perdirective acoustic receiving arrays;and the Bessel-azimuthal multipole(BEAM)approach developed herein.Several arrays are identified as being superdirective with extremely high FTBR values.The performance characteristics of the arrays of unidirectional elements are demonstrated to be superior in general.Moreover,it is shown that larger radius arrays with RQ-specified excitation amplitudes are robust to changes in them whereas the outcomes of the corresponding small radius versions are not.On the other hand,the BEAM-optimized densely-packed small-radius superdirective arrays are quite tolerant to those variations while generating unidirectional pseudo-needle beams. 展开更多
关键词 DIRECTIVITY Huygens dipole antennas MULTIPOLES Needle radiation Optimization Superdirective arrays Uniform circular arrays.
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Progress,challenges,and prospects of spent lithium-ion batteries recycling:A review 被引量:3
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作者 Pengwei Li Shaohua Luo +7 位作者 Lin Zhang Qiuyue Liu Yikai Wang Yicheng Lin Can Xu Jia Guo Peam Cheali Xiaoning Xia 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第2期144-171,I0005,共29页
The recycling and reutilization of spent lithium-ion batteries(LIBs)have become an important measure to alleviate problems like resource scarcity and environmental pollution.Although some progress has been made,batter... The recycling and reutilization of spent lithium-ion batteries(LIBs)have become an important measure to alleviate problems like resource scarcity and environmental pollution.Although some progress has been made,battery recycling technology still faces challenges in terms of efficiency,effectiveness and environmental sustainability.This review aims to systematically review and analyze the current status of spent LIB recycling,and conduct a detailed comparison and evaluation of different recycling processes.In addition,this review introduces emerging recycling techniques,including deep eutectic solvents,molten salt roasting,and direct regeneration,with the intent of enhancing recycling efficiency and diminishing environmental repercussions.Furthermore,to increase the added value of recycled materials,this review proposes the concept of upgrading recycled materials into high value-added functional materials,such as catalysts,adsorbents,and graphene.Through life cycle assessment,the paper also explores the economic and environmental impacts of current battery recycling and highlights the importance that future recycling technologies should achieve a balance between recycling efficiency,economics and environmental benefits.Finally,this review outlines the opportunities and challenges of recycling key materials for next-generation batteries,and proposes relevant policy recommendations to promote the green and sustainable development of batteries,circular economy,and ecological civilization. 展开更多
关键词 Spent li-ion batteries RECYCLE Direct regeneration High-value conversion Functional materials
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Cell reprogramming therapy for Parkinson’s disease 被引量:5
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作者 Wenjing Dong Shuyi Liu +1 位作者 Shangang Li Zhengbo Wang 《Neural Regeneration Research》 SCIE CAS CSCD 2024年第11期2444-2455,共12页
Parkinson’s disease is typically characterized by the progressive loss of dopaminergic neurons in the substantia nigra pars compacta.Many studies have been performed based on the supplementation of lost dopaminergic ... Parkinson’s disease is typically characterized by the progressive loss of dopaminergic neurons in the substantia nigra pars compacta.Many studies have been performed based on the supplementation of lost dopaminergic neurons to treat Parkinson’s disease.The initial strategy for cell replacement therapy used human fetal ventral midbrain and human embryonic stem cells to treat Parkinson’s disease,which could substantially alleviate the symptoms of Parkinson’s disease in clinical practice.However,ethical issues and tumor formation were limitations of its clinical application.Induced pluripotent stem cells can be acquired without sacrificing human embryos,which eliminates the huge ethical barriers of human stem cell therapy.Another widely considered neuronal regeneration strategy is to directly reprogram fibroblasts and astrocytes into neurons,without the need for intermediate proliferation states,thus avoiding issues of immune rejection and tumor formation.Both induced pluripotent stem cells and direct reprogramming of lineage cells have shown promising results in the treatment of Parkinson’s disease.However,there are also ethical concerns and the risk of tumor formation that need to be addressed.This review highlights the current application status of cell reprogramming in the treatment of Parkinson’s disease,focusing on the use of induced pluripotent stem cells in cell replacement therapy,including preclinical animal models and progress in clinical research.The review also discusses the advancements in direct reprogramming of lineage cells in the treatment of Parkinson’s disease,as well as the controversy surrounding in vivo reprogramming.These findings suggest that cell reprogramming may hold great promise as a potential strategy for treating Parkinson’s disease. 展开更多
关键词 animal models ASTROCYTES AUTOLOGOUS cell reprogramming cell therapy direct lineage reprogramming dopaminergic neurons induced pluripotent stem cells non-human primates Parkinson’s disease
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Anisotropic time-dependent behaviors of shale under direct shearing and associated empirical creep models 被引量:2
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作者 Yachen Xie Michael Z.Hou +1 位作者 Hejuan Liu Cunbao Li 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第4期1262-1279,共18页
Understanding the anisotropic creep behaviors of shale under direct shearing is a challenging issue.In this context,we conducted shear-creep and steady-creep tests on shale with five bedding orientations (i.e.0°,... Understanding the anisotropic creep behaviors of shale under direct shearing is a challenging issue.In this context,we conducted shear-creep and steady-creep tests on shale with five bedding orientations (i.e.0°,30°,45°,60°,and 90°),under multiple levels of direct shearing for the first time.The results show that the anisotropic creep of shale exhibits a significant stress-dependent behavior.Under a low shear stress,the creep compliance of shale increases linearly with the logarithm of time at all bedding orientations,and the increase depends on the bedding orientation and creep time.Under high shear stress conditions,the creep compliance of shale is minimal when the bedding orientation is 0°,and the steady-creep rate of shale increases significantly with increasing bedding orientations of 30°,45°,60°,and 90°.The stress-strain values corresponding to the inception of the accelerated creep stage show an increasing and then decreasing trend with the bedding orientation.A semilogarithmic model that could reflect the stress dependence of the steady-creep rate while considering the hardening and damage process is proposed.The model minimizes the deviation of the calculated steady-state creep rate from the observed value and reveals the behavior of the bedding orientation's influence on the steady-creep rate.The applicability of the five classical empirical creep models is quantitatively evaluated.It shows that the logarithmic model can well explain the experimental creep strain and creep rate,and it can accurately predict long-term shear creep deformation.Based on an improved logarithmic model,the variations in creep parameters with shear stress and bedding orientations are discussed.With abovementioned findings,a mathematical method for constructing an anisotropic shear creep model of shale is proposed,which can characterize the nonlinear dependence of the anisotropic shear creep behavior of shale on the bedding orientation. 展开更多
关键词 Rock anisotropy Direct shear creep Creep compliance Steady-creep rate Empirical model Creep constitutive model
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Review on laser directed energy deposited aluminum alloys 被引量:2
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作者 Tian-Shu Liu Peng Chen +7 位作者 Feng Qiu Hong-Yu Yang Nicholas Tan Yew Jin Youxiang Chew Di Wang Ruidi Li Qi-Chuan Jiang Chaolin Tan 《International Journal of Extreme Manufacturing》 SCIE EI CAS CSCD 2024年第2期84-131,共48页
Lightweight aluminum(Al)alloys have been widely used in frontier fields like aerospace and automotive industries,which attracts great interest in additive manufacturing(AM)to process high-value Al parts.As a mainstrea... Lightweight aluminum(Al)alloys have been widely used in frontier fields like aerospace and automotive industries,which attracts great interest in additive manufacturing(AM)to process high-value Al parts.As a mainstream AM technique,laser-directed energy deposition(LDED)shows good scalability to meet the requirements for large-format component manufacturing and repair.However,LDED Al alloys are highly challenging due to their inherent poor printability(e.g.low laser absorption,high oxidation sensitivity and cracking tendency).To further promote the development of LDED high-performance Al alloys,this review offers a deep understanding of the challenges and strategies to improve printability in LDED Al alloys.The porosity,cracking,distortion,inclusions,element evaporation and resultant inferior mechanical properties(worse than laser powder bed fusion)are the key challenges in LDED Al alloys.Processing parameter optimizations,in-situ alloy design,reinforcing particle addition and field assistance are the efficient approaches to improving the printability and performance of LDED Al alloys.The underlying correlations between processes,alloy innovation,characteristic microstructures,and achievable performances in LDED Al alloys are discussed.The benchmark mechanical properties and primary strengthening mechanism of LDED Al alloys are summarized.This review aims to provide a critical and in-depth evaluation of current progress in LDED Al alloys.Future opportunities and perspectives in LDED high-performance Al alloys are also outlined. 展开更多
关键词 additive manufacturing laser directed energy deposition(LDED) aluminum alloys PRINTABILITY aluminum matrix composite auxiliary fields mechanical properties
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Complication rates after direct anterior vs posterior approach for hip hemiarthroplasty in elderly individuals with femoral neck fractures 被引量:2
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作者 Tatiana Charles Nicolas Bloemers +1 位作者 Bilal Kapanci Marc Jayankura 《World Journal of Orthopedics》 2024年第1期22-29,共8页
BACKGROUND Dislocation rates after hemiarthroplasty reportedly vary from 1%to 17%.This serious complication is associated with increased morbidity and mortality rates.Approaches to this surgery are still debated,with ... BACKGROUND Dislocation rates after hemiarthroplasty reportedly vary from 1%to 17%.This serious complication is associated with increased morbidity and mortality rates.Approaches to this surgery are still debated,with no consensus regarding the superiority of any single approach.AIM To compare early postoperative complications after implementing the direct anterior and posterior approaches(PL)for hip hemiarthroplasty after femoral neck fractures.METHODS This is a comparative,retrospective,single-center cohort study conducted at a university hospital.Between March 2008 and December 2018,273 patients(a total of 280 hips)underwent bipolar hemiarthroplasties(n=280)for displaced femoral neck fractures using either the PL(n=171)or the minimally invasive direct anterior approach(DAA)(n=109).The choice of approach was related to the surgeons’practices;the implant types were similar and unrelated to the approach.Dislocation rates and other complications were reviewed after a minimum followup of 6 mo.RESULTS Both treatment groups had similarly aged patients(mean age:82 years),sex ratios,patient body mass indexes,and patient comorbidities.Surgical data(surgery delay time,operative time,and blood loss volume)did not differ significantly between the groups.The 30 d mortality rate was higher in the PL group(9.9%)than in the DAA group(3.7%),but the difference was not statistically significant(P=0.052).Among the one-month survivors,a significantly higher rate of dislocation was observed in the PL group(14/154;9.1%)than in the DAA group(0/105;0%)(P=0.002).Of the 14 patients with dislocation,8 underwent revision surgery for recurrent instability(posterior group),and one of them had 2 additional procedures due to a deep infection.The rate of other complications(e.g.,perioperative and early postoperative periprosthetic fractures and infection-related complications)did not differ significantly between the groups.CONCLUSION These findings suggest that the DAA to bipolar hemiarthroplasty for patients with femoral neck fractures is associated with a lower dislocation rate(<1%)than the PL. 展开更多
关键词 HEMIARTHROPLASTY Femoral neck fracture Direct anterior approach Posterior approach DISLOCATION MORTALITY
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Theoretical analysis of hydrogen solubility in direct coal liquefaction solvents 被引量:1
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作者 Xiaobin Zhang Aoqi Wang +1 位作者 Xingbao Wang Wenying Li 《International Journal of Coal Science & Technology》 EI CAS CSCD 2024年第2期187-197,共11页
The cyclic hydrogenation technology in a direct coal liquefaction process relies on the dissolved hydrogen of the solvent or oil participating in the hydrogenation reaction.Thus,a theoretical basis for process optimiz... The cyclic hydrogenation technology in a direct coal liquefaction process relies on the dissolved hydrogen of the solvent or oil participating in the hydrogenation reaction.Thus,a theoretical basis for process optimization and reactor design can be established by analyzing the solubility of hydrogen in liquefaction solvents.Experimental studies of hydrogen solubility in liquefaction solvents are challenging due to harsh reaction conditions and complex solvent compositions.In this study,the composition and content of liquefied solvents were analyzed.As model compounds,hexadecane,toluene,naphthalene,tetrahydronaphthalene,and phenanthrene were chosen to represent the liquefied solvents in chain alkanes and monocyclic,bicyclic,and tricyclic aromatic hydrocarbons.The solubility of hydrogen X(mol/mol)in pure solvent components and mixed solvents(alkanes and aromatics mixed in proportion to the chain alkanes+bicyclic aromatic hydrocarbons,bicyclic saturated aromatic hydrocarbons+bicyclic aromatic hydrocarbons,and bicyclic aromatic hydrocarbons+compounds containing het-eroatoms composed of mixed components)are determined using Aspen simulation at temperature and pressure conditions of 373–523 K and 2–10 MPa.The results demonstrated that at high temperatures and pressures,the solubility of hydrogen in the solvent increases with the increase in temperature and pressure,with the pressure having a greater impact.Further-more,the results revealed that hydrogen is more soluble in straight-chain alkanes than in other solvents,and the solubility of eicosanoids reaches a maximum of 0.296.The hydrogen solubility in aromatic ring compounds decreased gradually with an increase in the aromatic ring number.The influence of chain alkanes on the solubility of hydrogen predominates in a mixture of solvents with different mixing ratios of chain alkanes and aromatic hydrocarbons.The solubility of hydrogen in mixed aromatic solvents is less than that in the corresponding single solvents.Hydrogen is less soluble in solvent compounds containing heteroatoms than in compounds without heteroatoms. 展开更多
关键词 Direct coal liquefaction Liquefaction solvents Process simulation Hydrogen solubility
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Engineering Nano/Microscale Chiral Self‑Assembly in 3D Printed Constructs 被引量:1
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作者 Mohsen Esmaeili Ehsan Akbari +3 位作者 Kyle George Gelareh Rezvan Nader Taheri‑Qazvini Monirosadat Sadati 《Nano-Micro Letters》 SCIE EI CSCD 2024年第3期313-332,共20页
Helical hierarchy found in biomolecules like cellulose,chitin,and collagen underpins the remarkable mechanical strength and vibrant colors observed in living organisms.This study advances the integration of helical/ch... Helical hierarchy found in biomolecules like cellulose,chitin,and collagen underpins the remarkable mechanical strength and vibrant colors observed in living organisms.This study advances the integration of helical/chiral assembly and 3D printing technology,providing precise spatial control over chiral nano/microstructures of rod-shaped colloidal nanoparticles in intricate geometries.We designed reactive chiral inks based on cellulose nanocrystal(CNC)suspensions and acrylamide monomers,enabling the chiral assembly at nano/microscale,beyond the resolution seen in printed materials.We employed a range of complementary techniques including Orthogonal Superposition rheometry and in situ rheo-optic measurements under steady shear rate conditions.These techniques help us to understand the nature of the nonlinear flow behavior of the chiral inks,and directly probe the flow-induced microstructural dynamics and phase transitions at constant shear rates,as well as their post-flow relaxation.Furthermore,we analyzed the photo-curing process to identify key parameters affecting gelation kinetics and structural integrity of the printed object within the supporting bath.These insights into the interplay between the chiral inks self-assembly dynamics,3D printing flow kinematics and photopolymerization kinetics provide a roadmap to direct the out-of-equilibrium arrangement of CNC particles in the 3D printed filaments,ranging from uniform nematic to 3D concentric chiral structures with controlled pitch length,as well as random orientation of chiral domains.Our biomimetic approach can pave the way for the creation of materials with superior mechanical properties or programable photonic responses that arise from 3D nano/microstructure and can be translated into larger scale 3D printed designs. 展开更多
关键词 Directed chiral self-assembly Cellulose nanocrystals Bioinspired nanocomposite 3D printing RHEOLOGY
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Post-transcriptional mechanisms controlling neurogenesis and direct neuronal reprogramming 被引量:1
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作者 Elsa Papadimitriou Dimitra Thomaidou 《Neural Regeneration Research》 SCIE CAS CSCD 2024年第9期1929-1939,共11页
Neurogenesis is a tightly regulated process in time and space both in the developing embryo and in adult neurogenic niches.A drastic change in the transcriptome and proteome of radial glial cells or neural stem cells ... Neurogenesis is a tightly regulated process in time and space both in the developing embryo and in adult neurogenic niches.A drastic change in the transcriptome and proteome of radial glial cells or neural stem cells towards the neuronal state is achieved due to sophisticated mechanisms of epigenetic,transcriptional,and post-transcriptional regulation.Understanding these neurogenic mechanisms is of major importance,not only for shedding light on very complex and crucial developmental processes,but also for the identification of putative reprogramming factors,that harbor hierarchically central regulatory roles in the course of neurogenesis and bare thus the capacity to drive direct reprogramming towards the neuronal fate.The major transcriptional programs that orchestrate the neurogenic process have been the focus of research for many years and key neurogenic transcription factors,as well as repressor complexes,have been identified and employed in direct reprogramming protocols to convert non-neuronal cells,into functional neurons.The post-transcriptional regulation of gene expression during nervous system development has emerged as another important and intricate regulatory layer,strongly contributing to the complexity of the mechanisms controlling neurogenesis and neuronal function.In particular,recent advances are highlighting the importance of specific RNA binding proteins that control major steps of mRNA life cycle during neurogenesis,such as alternative splicing,polyadenylation,stability,and translation.Apart from the RNA binding proteins,microRNAs,a class of small non-coding RNAs that block the translation of their target mRNAs,have also been shown to play crucial roles in all the stages of the neurogenic process,from neural stem/progenitor cell proliferation,neuronal differentiation and migration,to functional maturation.Here,we provide an overview of the most prominent post-transcriptional mechanisms mediated by RNA binding proteins and microRNAs during the neurogenic process,giving particular emphasis on the interplay of specific RNA binding proteins with neurogenic microRNAs.Taking under consideration that the molecular mechanisms of neurogenesis exert high similarity to the ones driving direct neuronal reprogramming,we also discuss the current advances in in vitro and in vivo direct neuronal reprogramming approaches that have employed microRNAs or RNA binding proteins as reprogramming factors,highlighting the so far known mechanisms of their reprogramming action. 展开更多
关键词 direct neuronal reprogramming in vivo glia-to-neuron conversion microRNAs NEUROGENESIS post-transcriptional regulation RNA binding proteins
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Measurement of the high energyγ-rays from heavy ion reactions usingČerenkov detector 被引量:1
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作者 Da-Wei Si Yan Zhou +7 位作者 Sheng Xiao Zhi Qin Dong Guo Yu-Hao Qin Yi-Jie Wang Bo-Yuan Zhang Bai-Ting Tian Zhi-Gang Xiao 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2024年第2期123-130,共8页
The energetic bremsstrahlung photons up to 100 MeV produced in heavy ion collisions can be used as a sensitive probe for short-range correlation in atomic nuclei. The energy of the γ-rays can be measured by collectin... The energetic bremsstrahlung photons up to 100 MeV produced in heavy ion collisions can be used as a sensitive probe for short-range correlation in atomic nuclei. The energy of the γ-rays can be measured by collecting the Čerenkov light in the medium induced by the fast electrons generated in the Compton scattering or electromagnetic shower of the incident γray. Two types of detectors based on pure water and lead glass as sensitive materials were designed for this purpose. The γresponse and optical photon propagation in the detectors were simulated based on electromagnetic and optical processes in Geant4. The inherent energy resolutions of 0.022(4) + 0.51(2)∕E^(1/2)_(γ) for water and 0.0026(3) + 0.446(3)∕E^(1/2)_(γ) for lead glass were obtained. The geometry sizes of the lead glass and water were optimized to 30 cm × 30 cm × 30 cm and 60 cm × 60 cm ×120 cm, respectively, to detect high-energy γ-rays at 160 MeV. The Hough transform method was applied to reconstruct the direction of the incident γ-rays, providing the ability to experimentally distinguish the high-energy γ-rays produced in the reactions on the target from random background cosmic-ray muons. 展开更多
关键词 Bremsstrahlungγ-rays Čerenkov GEANT4 Energy resolution Direction reconstruction Hough transform
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Two-photon live imaging of direct glia-to-neuron conversion in the mouse cortex 被引量:1
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作者 Zongqin Xiang Shu He +13 位作者 Rongjie Chen Shanggong Liu Minhui Liu Liang Xu Jiajun Zheng Zhouquan Jiang Long Ma Ying Sun Yongpeng Qin Yi Chen Wen Li Xiangyu Wang Gong Chen Wenliang Lei 《Neural Regeneration Research》 SCIE CAS CSCD 2024年第8期1781-1788,共8页
Over the past decade,a growing number of studies have reported transcription factor-based in situ reprogramming that can directly conve rt endogenous glial cells into functional neurons as an alternative approach for ... Over the past decade,a growing number of studies have reported transcription factor-based in situ reprogramming that can directly conve rt endogenous glial cells into functional neurons as an alternative approach for n euro regeneration in the adult mammalian central ne rvous system.Howeve r,many questions remain regarding how a terminally differentiated glial cell can transform into a delicate neuron that forms part of the intricate brain circuitry.In addition,concerns have recently been raised around the absence of astrocyte-to-neuron conversion in astrocytic lineage-tra cing mice.In this study,we employed repetitive two-photon imaging to continuously capture the in situ astrocyte-to-neuron conversion process following ecto pic expression of the neural transcription factor NeuroD1 in both prolife rating reactive astrocytes and lineage-tra ced astrocytes in the mouse cortex.Time-lapse imaging over several wee ks revealed the ste p-by-step transition from a typical astrocyte with numero us short,tapered branches to a typical neuro n with a few long neurites and dynamic growth cones that actively explored the local environment.In addition,these lineage-converting cells were able to migrate ra dially or to ngentially to relocate to suitable positions.Furthermore,two-photon Ca2+imaging and patch-clamp recordings confirmed that the newly generated neuro ns exhibited synchronous calcium signals,repetitive action potentials,and spontaneous synaptic responses,suggesting that they had made functional synaptic connections within local neural circuits.In conclusion,we directly visualized the step-by-step lineage conversion process from astrocytes to functional neurons in vivo and unambiguously demonstrated that adult mammalian brains are highly plastic with respect to their potential for neuro regeneration and neural circuit reconstruction. 展开更多
关键词 astrocyte-to-neuron conversion Ca2+imaging direct lineage conversion GLIA ASTROCYTE in vivo reprogramming lineage-tracing mice NeuroD1 NEURON two-photon imaging
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Intrahepatic portal venous systems in adult patients with cavernous transformation of portal vein: Imaging features and a new classification 被引量:1
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作者 Xin Huang Qian Lu +5 位作者 Yue-Wei Zhang Lin Zhang Zhi-Zhong Ren Xiao-Wei Yang Ying Liu Rui Tang 《Hepatobiliary & Pancreatic Diseases International》 SCIE CAS CSCD 2024年第5期481-486,共6页
Background: Cavernous transformation of the portal vein(CTPV) due to portal vein obstruction is a rare vascular anomaly defined as the formation of multiple collateral vessels in the hepatic hilum. This study aimed to... Background: Cavernous transformation of the portal vein(CTPV) due to portal vein obstruction is a rare vascular anomaly defined as the formation of multiple collateral vessels in the hepatic hilum. This study aimed to investigate the imaging features of intrahepatic portal vein in adult patients with CTPV and establish the relationship between the manifestations of intrahepatic portal vein and the progression of CTPV. Methods: We retrospectively analyzed 14 CTPV patients in Beijing Tsinghua Changgung Hospital. All patients underwent both direct portal venography(DPV) and computed tomography angiography(CTA) to reveal the manifestations of the portal venous system. The vessels measured included the left portal vein(LPV), right portal vein(RPV), main portal vein(MPV) and the portal vein bifurcation(PVB). Results: Nine males and 5 females, with a median age of 40.5 years, were included in the study. No significant difference was found in the diameters of the LPV or RPV measured by DPV and CTA. The visualization in terms of LPV, RPV and PVB measured by DPV was higher than that by CTA. There was a significant association between LPV/RPV and PVB/MPV in term of visibility revealed with DPV( P = 0.01), while this association was not observed with CTA. According to the imaging features of the portal vein measured by DPV, CTPV was classified into three categories to facilitate the diagnosis and treatment. Conclusions: DPV was more accurate than CTA for revealing the course of the intrahepatic portal vein in patients with CTPV. The classification of CTPV, that originated from the imaging features of the portal vein revealed by DPV, may provide a new perspective for the diagnosis and treatment of CTPV. 展开更多
关键词 Cavernous transformation of the portal vein CLASSIFICATION Direct portal venography Intrahepatic portal venous system
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