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2024 Wheelchair Compendium of Physical Activities:An update of activity codes and energy expenditure values 被引量:4
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作者 Scott A.Conger Stephen D.Herrmann +3 位作者 Erik A.Willis Tom E.Nightingale Joseph R.Sherman Barbara E.Ainsworth 《Journal of Sport and Health Science》 SCIE CSCD 2024年第1期18-23,共6页
Purpose:This paper presents an update of the 2011 Wheelchair Compendium of Physical Activities designed for wheelchair users and is referred to as the 2024 Wheelchair Compendium.The Wheelchair Compendium aims to curat... Purpose:This paper presents an update of the 2011 Wheelchair Compendium of Physical Activities designed for wheelchair users and is referred to as the 2024 Wheelchair Compendium.The Wheelchair Compendium aims to curate existing knowledge of the energy expenditure for wheelchair physical activities(PAs).Methods:A systematic review of the published energy expenditure of PA for wheelchair users was completed between 2011 and May 2023.We added these data to the 2011 Wheelchair Compendium data that was compiled previously in a systematic review through 2011.Results:A total of 47 studies were included,and 124 different wheelchair PA reported energy expenditure values ranging from 0.8 metabolic equivalents for wheelchair users(filing papers,light effort)to 11.8 metabolic equivalents for wheelchair users(Nordic sit skiing).Conclusion:In introducing the updated 2024 Wheelchair Compendium,we hope to bridge the resource gap and challenge the prevailing narratives that inadvertently exclude wheelchair users from physical fitness and health PAs. 展开更多
关键词 DISABILITY EXERCISE MET Mobility
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Thermochemical splitting of CO_(2) on perovskites for CO production: A review
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作者 Biduan Chen Harriet Kildahl +3 位作者 Hui Yang Yulong Ding Lige Tong Li Wang 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第3期464-485,I0011,共23页
Energy supply dominated by fossil energy has been and remains the main cause of carbon dioxide emissions,the major greenhouse gas leading to the current grave climate change challenges.Many technical pathways have bee... Energy supply dominated by fossil energy has been and remains the main cause of carbon dioxide emissions,the major greenhouse gas leading to the current grave climate change challenges.Many technical pathways have been proposed to address the challenges.Carbon capture and utilization(CCU) represents one of the approaches and thermochemical CO_(2) splitting driven by thermal energy is a subset of the CCU,which converts the captured CO_(2) into CO and makes it possible to achieve closed-loop carbon recirculation.Redox-active catalysts are among the most critical components of the thermochemical splitting cycles and perovskites are regarded as the most promising catalysts.Here we review the latest advancements in thermochemical cycles based on perovskites,covering thermodynamic principles,material modifications,reaction kinetics,oxygen pressure control,circular strategies,and demonstrations to provide a comprehensive overview of the topical area.Thermochemical cycles based on such materials require the consideration of trade-off between cost and efficiency,which is related to actual material used,operation mode,oxygen removal,and heat recovery.Lots of efforts have been made towards improving reaction rates,conversion efficiency and cycling stability,materials related research has been lacking-a key aspect affecting the performance across all above aspects.Double perovskites and composite perovskites arise recently as a potentially promising addition to material candidates.For such materials,more effective oxygen removal would be needed to enhance the overall efficiency,for which thermochemical or electrochemical oxygen pumps could contribute to efficient oxygen removal as well as serve as means for inert gas regeneration.The integration of thermochemical CO_(2) splitting process with downstream fuel production and other processes could reduce costs and increase efficiency of the technology.This represents one of the directions for the future research. 展开更多
关键词 Perovskite Thermochemical cycles CO_(2) splitting Fuel production Non-stoichiometric
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A coordinated operation method of wind-PV-hydrogenstorage multi-agent energy system
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作者 Tengfei Ma Wei Pei +3 位作者 Yanhong Yang Hao Xiao Chenghong Tang Weiqi Hua 《Global Energy Interconnection》 EI CSCD 2024年第4期446-461,共16页
Wind-photovoltaic(PV)-hydrogen-storage multi-agent energy systems are expected to play an important role in promoting renewable power utilization and decarbonization.In this study,a coordinated operation method was pr... Wind-photovoltaic(PV)-hydrogen-storage multi-agent energy systems are expected to play an important role in promoting renewable power utilization and decarbonization.In this study,a coordinated operation method was proposed for a wind-PVhydrogen-storage multi-agent energy system.First,a coordinated operation model was formulated for each agent considering peer-to-peer power trading.Second,a coordinated operation interactive framework for a multi-agent energy system was proposed based on the theory of the alternating direction method of multipliers.Third,a distributed interactive algorithm was proposed to protect the privacy of each agent and solve coordinated operation strategies.Finally,the effectiveness of the proposed coordinated operation method was tested on multi-agent energy systems with different structures,and the operational revenues of the wind power,PV,hydrogen,and energy storage agents of the proposed coordinated operation model were improved by approximately 59.19%,233.28%,16.75%,and 145.56%,respectively,compared with the independent operation model. 展开更多
关键词 Wind-PV-hydrogen-storage Multi-agent energy system Renewable power to hydrogen Coordinated operation Peer-to-peer power trading
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Numerical analysis of high‑speed railway slab tracks using calibrated and validated 3D time‑domain modelling
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作者 A.F.Esen O.Laghrouche +4 位作者 P.K.Woodward D.Medina‑Pineda Q.Corbisez J.Y.Shih D.P.Connolly 《Railway Engineering Science》 EI 2024年第1期36-58,共23页
Concrete slabs are widely used in modern railways to increase the inherent resilient quality of the tracks,provide safe and smooth rides,and reduce the maintenance frequency.In this paper,the elastic performance of a ... Concrete slabs are widely used in modern railways to increase the inherent resilient quality of the tracks,provide safe and smooth rides,and reduce the maintenance frequency.In this paper,the elastic performance of a novel slab trackform for high-speed railways is investigated using three-dimensional finite element modelling in Abaqus.It is then compared to the performance of a ballasted track.First,slab and ballasted track models are developed to replicate the full-scale testing of track sections.Once the models are calibrated with the experimental results,the novel slab model is developed and compared against the calibrated slab track results.The slab and ballasted track models are then extended to create linear dynamic models,considering the track geodynamics,and simulating train passages at various speeds,for which the Ledsgard documented case was used to validate the models.Trains travelling at low and high speeds are analysed to investigate the track deflections and the wave propagation in the soil,considering the issues associated with critical speeds.Various train loading methods are discussed,and the most practical approach is retained and described.Moreover,correlations are made between the geotechnical parameters of modern high-speed rail and conventional standards.It is found that considering the same ground condition,the slab track deflections are considerably smaller than those of the ballasted track at high speeds,while they show similar behaviour at low speeds. 展开更多
关键词 High-speed railways Slab track New ballastless track Ballasted track Critical speeds Finite element modelling Calibration of numerical models
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Formation environment and hydrocarbon potential of the Paleogene Enping Formation coal measures in the ZhuⅠDepression of northern South China Sea
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作者 Yuting Yin Lei Lan +5 位作者 Dongdong Wang Ying Chen Yan Liu Youchuan Li Zengxue Li Jiamin Liu 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2024年第4期119-135,共17页
The coal-measure source rock in the Chinese sea area plays a significant role as a hydrocarbon source rock,with its genetic environment,development and distribution,and hydrocarbon generation potential serving as esse... The coal-measure source rock in the Chinese sea area plays a significant role as a hydrocarbon source rock,with its genetic environment,development and distribution,and hydrocarbon generation potential serving as essential factors for the exploration of coal-type oil and gas fields.This study focuses on the coal-measure source rock of the Paleogene Enping Formation in the ZhuⅠDepression,located in the northern South China Sea.The main geological insights obtained are as follows.The coal measures of the Enping Formation are developed in a warm and wet tropical-subtropical climate.The development environment of the coal-measure source rock in the Enping Formation includes the braided river delta upper plain peat swamp,characterized by dry forest swamp coal facies with relatively thick coal seams and a small number of layers.The braided river delta lower plain swamp-interdistributary bay of braided river delta front represents a forest edge-wetland herbaceous swamp coal facies with numerous layers of thin coal seams and poor stability.The shore swamp corresponds to an open water swamp coal facies with multiple layers of thin coal seams and poor stability.The organic matter abundance in the braided river delta upper plain is the highest,followed by the braided river delta lower plain-braided river delta front,and the shore-shallow lake.The organic matter type is predominantly typeⅡ1.Thermal evolution analysis suggests that the organic matter has progressed into a substantial oil generation stage.The hydrocarbon generation potential of the coal-measure source rock in the Enping Formation is the highest in the braided river delta upper plain,followed by the braided river delta lower plain-braided river delta front and the shore-shallow lake.Overall,this study proposes three organic facies in the coal-measure source rock of the Enping Formation:upper-plain swamp-dry forest swamp facies,lower plain-interdistributary bay-forest-herbaceous swamp facies,and lake swamp-herbaceous swamp facies. 展开更多
关键词 coal-measure source rock PALEOGENE genetic environment hydrocarbon generation characteristic ZhuⅠDepression
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Astronomical influence of the development of Paleogene thin coal seam groups in offshore Lacustrine basins:A case study of the ZhuⅠDepression's Enping Formation located in the northern South China Sea
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作者 Yan Liu Shengbing Huang +4 位作者 Dongdong Wang Nan Li Yuting Yin Ying Chen Zengxue Li 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2024年第4期136-150,共15页
The development of the Paleogene coal seams in China's offshore basin areas generally had the characteristics of coal measures with large thicknesses,large numbers of coal seams,thin single coal seams,poor stabili... The development of the Paleogene coal seams in China's offshore basin areas generally had the characteristics of coal measures with large thicknesses,large numbers of coal seams,thin single coal seams,poor stability,scattered vertical distribution,and a wide distribution range.This study selected the Enping Formation of the ZhuⅠDepression in the northern section of the South China Sea as an example to determine the macro-control factors of the development of the Paleogene coal seam groups.An analysis was carried out on the influencing effects and patterns of the astronomical cycles related to the development of the thin coal seam groups in the region.A floating astronomical time scale of the Enping Formation was established,and the sedimentary time limit of the Enping Formation was determined to be approximately 6.15 Ma±.In addition,the cyclostratigraphy analysis results of the natural gamma-ray data of Well XJ in the Enping Formation of the Xijiang Sag revealed that the development of the thin coal seams had probably been affected by short eccentricity and precession factors.The formation process of coal seams was determined to have been affected by high seasonal contrast,precipitation,and insolation.During the periods with high values of short eccentricity,the seasonal contrasts tended to be high.During those periods,fluctuations in the precession controls resulted in periodic volume changes in precipitation and insolation of the region,resulting in the development of thin coal seams.It was also found that the periods with low precession were the most conducive to coal seam development.On that basis,combined with such factors as sedimentary environmental conditions conducive to the development of thin coal seam groups,this study established a theoretical model of the comprehensive influences of short eccentricity and precession on the development and distribution of Paleogene thin coal seam groups in offshore lacustrine basins.The patterns of the Paleogene astronomical periods and paleoclimate evolution,along with the control factors which impacted the development of thin coal seam groups in offshore lacustrine basins,were revealed. 展开更多
关键词 PALEOGENE Pearl(Zhujiang)River Mouth Basin coal seam development astronomical cycles
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Vascular endothelial growth factor:a double-edged sword in the development of white matter lesions
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作者 Narek Manukjan Daniel Fulton +2 位作者 Zubair Ahmed WMatthijs Blankesteijn Sébastien Foulquier 《Neural Regeneration Research》 SCIE CAS 2025年第1期191-192,共2页
As the population ages,the burden of age-related diseases becomes greater.Currently,over 55 million people suffer from dementia worldwide,with Alzheimer’s disease being the most common form.However,it is becoming cle... As the population ages,the burden of age-related diseases becomes greater.Currently,over 55 million people suffer from dementia worldwide,with Alzheimer’s disease being the most common form.However,it is becoming clearer that underlying vascular pathology such as cerebral small vessel disease(cSVD)may be a more detrimental cause for dementia(Cuadrado-Godia et al.,2018).It is estimated that 10%-30%of the elderly population and 35%-90%of all dementia patients exhibit signs of cSVD.The term cSVD refers to pathology affecting the small vessels of the brain,which can lead to lacunar cerebral infarcts,enlarged perivascular spaces,and cortical hemorrhages(Cuadrado-Godia et al.,2018).CSVD is often associated with cognitive decline,gait problems,and dementia(Cuadrado-Godia et al.,2018). 展开更多
关键词 PATHOLOGY BECOMING WHITE
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Management of distal cholangiocarcinoma with arterial involvement: Systematic review and case series on the role of neoadjuvant therapy
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作者 Lewis A Hall Duncan Loader +12 位作者 Santiago Gouveia Marta Burak James Halle-Smith Peter Labib Moath Alarabiyat Ravi Marudanayagam Bobby V Dasari Keith J Roberts Syed S Raza Michail Papamichail David C Bartlett Robert P Sutcliffe Nikolaos A Chatzizacharias 《World Journal of Gastrointestinal Surgery》 SCIE 2024年第8期2689-2701,共13页
BACKGROUND The use of neoadjuvant therapy(NAT)in distal cholangiocarcinoma(dCCA)with regional arterial or extensive venous involvement,is not widely accepted and evidence is sparse.AIM To synthesise evidence on NAT fo... BACKGROUND The use of neoadjuvant therapy(NAT)in distal cholangiocarcinoma(dCCA)with regional arterial or extensive venous involvement,is not widely accepted and evidence is sparse.AIM To synthesise evidence on NAT for dCCA and present the experience of a highvolume tertiary-centre managing dCCA with arterial involvement.METHODS A systematic review was performed according to PRISMA guidance to identify all studies reporting outcomes of patients with dCCA who received NAT.All patients from 2017 to 2022 who were referred for NAT for dCCA at our centre were retrospectively collected from a prospectively maintained database.Baseline characteristics,NAT type,progression to surgery and oncological outcomes were collected.RESULTS Twelve studies were included.The definition of“unresectable”locally advanced dCCA was heterogenous.Four studies reported outcomes for 9 patients who received NAT for dCCA with extensive vascular involvement.R0 resection rate ranged between 0 and 100%but without survival benefit in most cases.Remaining studies considered either NAT in resectable dCCA or inclusive with extrahepatic CCA.The presented case series includes 9 patients(median age 67,IQR 56-74 years,male:female 5:4)referred for NAT for borderline resectable or locally advanced disease.Three patients progressed to surgery and 2 were resected.One patient died at 14 months with evidence of recurrence at 6 months and the other died at 51 months following recurrence 6 months postoperatively.CONCLUSION Evidence for benefit of NAT is limited.Consensus on criteria for uniform definition of resectability for dCCA is required.We propose using the established National-Comprehensive-Cancer-Network®criteria for pancreatic ductal adenocarcinoma. 展开更多
关键词 CHOLANGIOCARCINOMA Neoadjuvant therapy Arterial involvement Locally advanced Systematic review
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A framework for dynamic modelling of railway track switches considering the switch blades,actuators and control systems
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作者 Saikat Dutta Tim Harrison +2 位作者 Christopher Ward Roger Dixon Phil Winship 《Railway Engineering Science》 EI 2024年第2期162-176,共15页
The main contribution of this paper is the development and demonstration of a novel methodology that can be followed to develop a simulation twin of a railway track switch system to test the functionality in a digital... The main contribution of this paper is the development and demonstration of a novel methodology that can be followed to develop a simulation twin of a railway track switch system to test the functionality in a digital environment.This is important because,globally,railway track switches are used to allow trains to change routes;they are a key part of all railway networks.However,because track switches are single points of failure and safety-critical,their inability to operate correctly can cause significant delays and concomitant costs.In order to better understand the dynamic behaviour of switches during operation,this paper has developed a full simulation twin of a complete track switch system.The approach fuses finite element for the rail bending and motion,with physics-based models of the electromechanical actuator system and the control system.Hence,it provides researchers and engineers the opportunity to explore and understand the design space around the dynamic operation of new switches and switch machines before they are built.This is useful for looking at the modification or monitoring of existing switches,and it becomes even more important when new switch concepts are being considered and evaluated.The simulation is capable of running in real time or faster meaning designs can be iterated and checked interactively.The paper describes the modelling approach,demonstrates the methodology by developing the system model for a novel“REPOINT”switch system,and evaluates the system level performance against the dynamic performance requirements for the switch.In the context of that case study,it is found that the proposed new actuation system as designed can meet(and exceed)the system performance requirements,and that the fault tolerance built into the actuation ensures continued operation after a single actuator failure. 展开更多
关键词 Railway track switch Mathematical modelling Redundant actuation Finite element analysis
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Tale of mitochondria and mitochondria-associated ER membrane in patient-derived neuronal models of Wolfram syndrome
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作者 Laetitia Aubry Timothy Barrett Sovan Sarkar 《Neural Regeneration Research》 SCIE CAS 2025年第9期2587-2588,共2页
Mitochondria and mitochondria-associated endoplasmic reticulum membrane in neurodegenerative diseases:Mitochondria generate most of the chemical energy needed to power the biochemical reactions of cells,and thus are o... Mitochondria and mitochondria-associated endoplasmic reticulum membrane in neurodegenerative diseases:Mitochondria generate most of the chemical energy needed to power the biochemical reactions of cells,and thus are often referred to as the"powerhouse"of the cell.Nevertheless,this organelle is also involved in a pleth,ora of different cellular functions such as calcium(Ca^(2+))homeostasis,apoptosis,oxidative stress,and several metabolic pathways including oxidative phosphorylation,tricarboxylic acid cycle,andβ-oxidation of fatty acids. 展开更多
关键词 OXIDATIVE CYCLE carboxylic
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Role of targeted neuromodulation in the treatment of congenital unilateral lower lip palsy:A clinical case report
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作者 Hafiz Saqib Sikandar Ali Hassan Ameer Hamza 《Chinese Journal of Plastic and Reconstructive Surgery》 2024年第3期139-141,共3页
Congenital unilateral lower lip palsy(CULLP),or congenital hypoplasia of the depressor anguli oris muscle,also known as asymmetric crying facies,is a rare condition that results in asymmetry of the lower lip during sm... Congenital unilateral lower lip palsy(CULLP),or congenital hypoplasia of the depressor anguli oris muscle,also known as asymmetric crying facies,is a rare condition that results in asymmetry of the lower lip during smiling,laughing,and crying.Although the etiology is unknown,weakness of the depressor labii inferioris(DLI)muscle is implicated as a contributing factor.Currently,no well-established treatment options are available.This case report describes an 18-year-old male patient diagnosed with CULLP.Physical examination revealed a symmetric face at rest,but asymmetry when smiling and opening the mouth.Following the administration of lidocaine into the affected DLI muscle,the patient’s smile and lower lip symmetry were immediately restored without any adverse effects.Subsequently,administration of botulinum toxin for neuromodulation of the DLI muscle led to a significant improvement in symmetry and oral function within 2 weeks,which was sustained at 1 month and 3 months post-treatment.No adverse effects were reported,and both patients and families expressed high satisfaction with the outcomes.This case highlights the potential use of neuromodulation as a minimally invasive and effective treatment for CULLP. 展开更多
关键词 Facial paralysis Botulinum toxin Chemodenervation Asymmetric smile Congenital unilateral lower lip palsy Asymmetric crying facies
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Evaluation of the slipstream in different regions around a train with respect to different nose lengths:A comparison study
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作者 WANG Lei LIU Tang-hong +3 位作者 CHEN Zheng-wei ZENG Guang-zhi HEMIDA Hassan XIA Yu-tao 《Journal of Central South University》 SCIE EI CAS CSCD 2024年第9期3295-3311,共17页
In this work,the flow surrounding the train was obtained using a detached eddy simulation(DES)for slipstream analysis.Two different streamlined nose lengths were investigated:a short nose(4 m)and a long nose(9 m).The ... In this work,the flow surrounding the train was obtained using a detached eddy simulation(DES)for slipstream analysis.Two different streamlined nose lengths were investigated:a short nose(4 m)and a long nose(9 m).The time-average slipstream velocity and the time-average slipstream pressure along the car bodies were compared and explained in detail.In addition to the time-averaged values,the _(max)imum velocities and the pressure peak-to-peak values around the two trains were analyzed.The result showed that the nose length affected the slipstream velocity along the entire train length at the lower and upper regions of the side of the train.However,no significant effect was recognized at the middle height of the train along its length,except in the nose region.Moreover,within the train’s side regions(y=2.0-2.5 m and z=2-4 m)and(y=2.5-3.5 m and z=0.2-0.7 m),the ratio of slipstream velocity U_(max) between the short and long nose trains was notably higher.This occurrence also manifested at the train’s upper section,specifically where y=0-2.5 m and z=4.2-5.0 m.Similarly,regarding the ratio of _(max)imum pressure peak-to-peak values Cp-p_(max),significant regions were observed at the train’s side(y=1.8-2.6 m and z=1-4 m)and above the train(y=0-2 m and z=3.9-4.8 m). 展开更多
关键词 high-speed train nose length slipstream velocity pressure change
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Transcriptional reprogramming during human osteoclast differentiation identifies regulators of osteoclast activity
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作者 Morten S.Hansen Kaja Madsen +6 位作者 Maria Price Kent Søe Yasunori Omata Mario M.Zaiss Caroline M.Gorvin Morten Frost Alexander Rauch 《Bone Research》 SCIE CAS CSCD 2024年第1期180-198,共19页
Enhanced osteoclastogenesis and osteoclast activity contribute to the development of osteoporosis,which is characterized by increased bone resorption and inadequate bone formation.As novel antiosteoporotic therapeutic... Enhanced osteoclastogenesis and osteoclast activity contribute to the development of osteoporosis,which is characterized by increased bone resorption and inadequate bone formation.As novel antiosteoporotic therapeutics are needed,understanding the genetic regulation of human osteoclastogenesis could help identify potential treatment targets.This study aimed to provide an overview of transcriptional reprogramming during human osteoclast differentiation.Osteoclasts were differentiated from CD14+monocytes from eight female donors.RNA sequencing during differentiation revealed 8980 differentially expressed genes grouped into eight temporal patterns conserved across donors.These patterns revealed distinct molecular functions associated with postmenopausal osteoporosis susceptibility genes based on RNA from iliac crest biopsies and bone mineral density SNPs.Network analyses revealed mutual dependencies between temporal expression patterns and provided insight into subtype-specific transcriptional networks.The donor-specific expression patterns revealed genes at the monocyte stage,such as filamin B(FLNB)and oxidized low-density lipoprotein receptor 1(OLR1,encoding LOX-1),that are predictive of the resorptive activity of mature osteoclasts.The expression of differentially expressed G-protein coupled receptors was strong during osteoclast differentiation,and these receptors are associated with bone mineral density SNPs,suggesting that they play a pivotal role in osteoclast differentiation and activity.The regulatory effects of three differentially expressed G-protein coupled receptors were exemplified by in vitro pharmacological modulation of complement 5 A receptor 1(C5AR1),somatostatin receptor 2(SSTR2),and free fatty acid receptor 4(FFAR4/GPR120).Activating C5AR1 enhanced osteoclast formation,while activating SSTR2 decreased the resorptive activity of mature osteoclasts,and activating FFAR4 decreased both the number and resorptive activity of mature osteoclasts.In conclusion,we report the occurrence of transcriptional reprogramming during human osteoclast differentiation and identified SSTR2 and FFAR4 as antiresorptive G-protein coupled receptors and FLNB and LOX-1 as potential molecular markers of osteoclast activity.These data can help future investigations identify molecular regulators of osteoclast differentiation and activity and provide the basis for novel antiosteoporotic targets. 展开更多
关键词 OSTEOCLAST PROGRAMMING identif
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Cost Optimization of Steel Beam-to-Column Connections using AVOA
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作者 Ziyu Wang Zhaoyang Ren 《Journal of Architectural Research and Development》 2024年第2期18-23,共6页
The joint-bolt-African Vulture optimization algorithm(AVOA)model is proposed for the design of building connections to improve the stability of steel beam-to-column connections.For this algorithm,the type of steel is ... The joint-bolt-African Vulture optimization algorithm(AVOA)model is proposed for the design of building connections to improve the stability of steel beam-to-column connections.For this algorithm,the type of steel is first determined,and the number of bolts needed by the corresponding steel type is referenced in Eurocode 3.Then,the bearing capacity of the joint can be calculated.The joint-bolt-AVOA model is established by substituting the bolt number required by the steel into the algorithm to obtain the optimal bolt number required while ensuring joint stability.The results show that the number of bolts required by the joint-bolt-AVOA model based on the stability of steel is lower than that calculated by Eurocode 3.Therefore,AVOA can effectively optimize the number of bolts needed in building connections and save resources. 展开更多
关键词 Steel connections African vulture optimization algorithm Optimization of bolts
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SIMAP500: A novel risk score to identify recipients at higher risk of hepatocellular carcinoma recurrence following liver transplantation
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作者 Amr Alnagar Nekisa Zakeri +12 位作者 Konstantinos Koilias Rosemary E Faulkes Rachel Brown Owen Cain M Thamara P R Perera Keith J Roberts Rebeca Sanabria-Mateos David C Bartlett Yuk Ting Ma Shivan Sivakumar Shishir Shetty Tahir Shah Bobby V M Dasari 《World Journal of Transplantation》 2024年第3期132-143,共12页
BACKGROUND Recurrence of hepatocellular carcinoma(HCC)following liver transplantation(LT)has a devastating influence on recipients’survival;however,the risk of recur-rence is not routinely stratified.Risk stratificat... BACKGROUND Recurrence of hepatocellular carcinoma(HCC)following liver transplantation(LT)has a devastating influence on recipients’survival;however,the risk of recur-rence is not routinely stratified.Risk stratification is vital with a long LT waiting time,as that could influence the recurrence despite strict listing criteria.AIM This study aims to identify predictors of recurrence and develop a novel risk pre-diction score to forecast HCC recurrence following LT.METHODS A retrospective review of LT for HCC recipients at University Hospitals Bir-mingham between July 2011 and February 2020.Univariate and multivariate analyses were performed to identify recurrence predictors,based on which the novel SIMAP500(satellite nodules,increase in size,microvascular invasion,AFP>500,poor differentiation)risk score was proposed.RESULTS 234 LTs for HCC were performed with a median follow-up of 5.3 years.Recurrence developed in 25 patients(10.7%).On univariate analyses,RETREAT score>3,α-fetoprotein(AFP)at listing 100-500 and>500,bridging,increased tumour size between imaging at the listing time and explant histology,increase in the size of viable tumour between listing and explant,presence of satellite nodules,micro-and macrovascular invasion on explant and poor differentiation of tumours were significantly associated with recurrence,based on which,the SIMAP500 risk score is proposed.The SIMAP500 demonstrated an excellent predictive ability(c-index=0.803)and outper-formed the RETREAT score(c-index=0.73).SIMAP500 is indicative of the time to disease recurrence.CONCLUSION SIMAP500 risk score identifies the LT recipients at risk of HCC recurrence.Risk stratification allows patient-centric post-transplant surveillance programs.Further validation of the score is recommended. 展开更多
关键词 Liver transplantation Hepatocellular carcinoma RECURRENCE SURVIVAL
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International validation of the Chinese University Prognostic Index for staging of hepatocellular carcinoma: a joint United Kingdom and Hong Kong study 被引量:5
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作者 Stephen L.Chan Philip J.Johnson +8 位作者 Frankie Mo Sarah Berhane Mabel Teng Anthony W.H.Chan Ming C.Poon Paul B.S.Lai Simon Yu Anthony T.C.Chan Winnie Yeo 《Chinese Journal of Cancer》 SCIE CAS CSCD 2014年第10期481-491,共11页
The outcome of hepatocellular carcinoma(HCC) patients significantly differs between western and eastern population centers. Our group previously developed and validated the Chinese University Prognostic Index(CUPI) fo... The outcome of hepatocellular carcinoma(HCC) patients significantly differs between western and eastern population centers. Our group previously developed and validated the Chinese University Prognostic Index(CUPI) for the prognostication of HCC among the Asian HCC patient population. In the current study, we aimed to validate the CUPI using an international cohort of patients with HCC and to compare the CUPI to two widely used staging systems, the Barcelona Clinic Liver Cancer(BCLC) classification and the Cancer of the Liver Italian Program(CLIP). To accomplish this goal, two cohorts of patients were enrolled in the United Kingdom(UK; n = 567; 2006-2011) and Hong Kong(HK; n = 517; 2007-2012). The baseline clinical data were recorded. The performances of the CUPI, BCLC, and CLIP were compared in terms of a concordance index(C-index) and were evaluated in subgroups of patients according to treatment intent. The results revealed that the median follow-up durations of the UK and HK cohorts were 27.9 and 29.8 months, respectively. The median overall survival of the UK and HK cohorts were 22.9 and 8.6 months, respectively. The CUPI stratified the patients in both cohorts into three risk subgroups corresponding to distinct outcomes. The median overall survival of the CUPI low-, intermediate-, and high-risk subgroups were 3.15, 1.24, and 0.29 years, respectively, in the UK cohort and were 2.07, 0.32, and 0.10 years, respectively, in the HK cohort. For the patients who underwent curative treatment, the prognostic performance did not differ between the three staging systems, and all were suboptimal. For those who underwent palliative treatment, the CUPI displayed the highest C-index, indicating that this staging system was the most informative for both cohorts. In conclusion, the CUPI is applicable to both western and eastern HCC patient populations. The performances of the three staging systems differed according to treatment intent, and the CUPI was demonstrated to be optimal for those undergoing palliative treatment. A more precise staging system for early-stage disease patients is required. 展开更多
关键词 香港 英国 预后 肝癌 验证 国际 大学 中国
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Machine perfusion and the prevention of ischemic type biliary lesions following liver transplant:What is the evidence? 被引量:2
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作者 Manuel Durán Rafael Calleja +9 位作者 Angus Hann George Clarke Ruben Ciria Anisa Nutu Rebeca Sanabria-Mateos María Dolores Ayllón Pedro López-Cillero Hynek Mergental Javier Briceño M Thamara P R Perera 《World Journal of Gastroenterology》 SCIE CAS 2023年第20期3066-3083,共18页
The widespread uptake of different machine perfusion(MP)strategies for liver transplant has been driven by an effort to minimize graft injury.Damage to the cholangiocytes during the liver donation,preservation,or earl... The widespread uptake of different machine perfusion(MP)strategies for liver transplant has been driven by an effort to minimize graft injury.Damage to the cholangiocytes during the liver donation,preservation,or early posttransplant period may result in stricturing of the biliary tree and inadequate biliary drainage.This problem continues to trouble clinicians,and may have catastrophic consequences for the graft and patient.Ischemic injury,as a result of compromised hepatic artery flow,is a well-known cause of biliary strictures,sepsis,and graft failure.However,very similar lesions can appear with a patent hepatic artery and these are known as ischemic type biliary lesions(ITBL)that are attributed to microcirculatory dysfunction rather than main hepatic arterial compromise.Both the warm and cold ischemic period duration appear to influence the onset of ITBL.All of the commonly used MP techniques deliver oxygen to the graft cells,and therefore may minimize the cholangiocyte injury and subsequently reduce the incidence of ITBL.As clinical experience and published evidence grows for these modalities,the impact they have on ITBL rates is important to consider.In this review,the evidence for the three commonly used MP strategies(abdominal normothermic regional perfusion[A-NRP],hypothermic oxygenated perfusion[HOPE],and normothermic machine perfusion[NMP])for ITBL prevention has been critically reviewed.Inconsistencies with ITBL definitions used in trials,coupled with variations in techniques of MP,make interpretation challenging.Overall,the evidence suggests that both HOPE and A-NRP prevent ITBL in donated after circulatory death grafts compared to cold storage.The evidence for ITBL prevention in donor after brain death grafts with any MP technique is weak. 展开更多
关键词 Liver transplant Ischemic type biliary lesions Hypothermic oxygenated machine perfusion Normothermic machine perfusion Abdominal normothermic regional perfusion Donation after circulatory death
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Rail fastener detection of heavy railway based on deep learning 被引量:4
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作者 Yuan Cao Zihao Chen +3 位作者 Tao Wen Clive Roberts Yongkui Sun Shuai Su 《High-Speed Railway》 2023年第1期63-69,共7页
Image detection based on machine learning and deep learning currently has a good application prospect for railway fault diagnosis,with good performance in feature extraction and the accuracy of image localization and ... Image detection based on machine learning and deep learning currently has a good application prospect for railway fault diagnosis,with good performance in feature extraction and the accuracy of image localization and good classification results.To improve the speed of locating small target objects of fasteners,the YOLOv5 framework model with faster algorithm speed is selected.To improve the classification accuracy of fasteners,YOLOv5-based heavy-duty railway rail fastener detection is proposed.The anchor size is modified on the original basis to improve the attention to small targets of fasteners.The CBAM(Convolutional Block Attention Module)module and TPH(Transformer Prediction Head)module are introduced to improve the speed and accuracy issues.The rail fasteners are divided into 6 categories.Experiment comparisons show that before the improvement,the MAP@0.5 value of all categories are close to the peak of 0.989 after the epoch of 150,and the F1 score approaches 1 with confidence in the interval(0.2,0.95).The improved mAP@0.5 value approached the highest value of 0.991 after the epoch of 75,and the F1 score approached 1 with confidence in the interval(0.01,0.95).The experiment results indicate that the improved YOLOv5 model proposed in this paper is more suitable for the task of detecting rail fasteners. 展开更多
关键词 Rail fasteners Fault diagnosis Heavy haul railways Deep learning YOLO5
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A reasoning diagram based method for fault diagnosis of railway point system 被引量:1
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作者 Feng Wang Yuan Cao +4 位作者 Clive Roberts Tao Wen Lei Tan Shuai Su Tao Tang 《High-Speed Railway》 2023年第2期110-119,共10页
Railway Point System(RPS)is an important infrastructure in railway industry and its faults may have significant impacts on the safety and efficiency of train operations.For the fault diagnosis of RPS,most existing met... Railway Point System(RPS)is an important infrastructure in railway industry and its faults may have significant impacts on the safety and efficiency of train operations.For the fault diagnosis of RPS,most existing methods assume that sufficient samples of each failure mode are available,which may be unrealistic,especially for those modes of low occurrence frequency but with high risk.To address this issue,this work proposes a novel fault diagnosis method that only requires the power signals generated under normal RPS operations in the training stage.Specifically,the failure modes of RPS are distinguished through constructing a reasoning diagram,whose nodes are either binary logic problems or those that can be decomposed into the problems of the binary logic.Then,an unsupervised method for the signal segmentation and a fault detection method are combined to make decisions for each binary logic problem.Based on the results of decisions,the diagnostic rules are established to identify the failure modes.Finally,the data collected from multiple real-world RPSs are used for validation and the results demonstrate that the proposed method outperforms the benchmark in identifying the faults of RPSs. 展开更多
关键词 Railway point system Fault diagnosis Reasoning diagram SEGMENTATION Detection method
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A review of challenges and opportunities in micropillar compression studies in Mg alloys 被引量:1
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作者 A.Kodam M.S.Gundi +3 位作者 Y.L.Chiu I.P.Jones S.S.Singh J.Jain 《Journal of Magnesium and Alloys》 SCIE EI CAS CSCD 2023年第11期4043-4053,共11页
This review paper provides an overview of the micropillar compression technique as applied to magnesium(Mg) and its alloys. It explores the influence of various factors, such as pillar size, shape, temperature, and st... This review paper provides an overview of the micropillar compression technique as applied to magnesium(Mg) and its alloys. It explores the influence of various factors, such as pillar size, shape, temperature, and strain rate on the mechanical properties of Mg.Additionally, the impact of alloying elements, aging, and precipitates in Mg alloys has been extensively examined, revealing their significant influence on mechanical performance. The study highlights the strength and strain hardening improvements in Mg with decreasing pillar size in micropillar compression. Furthermore, the role of precipitates as strengthening agents, affecting deformation mechanisms and overall mechanical response, is explored. These valuable insights are crucial for designing Mg-based materials with enhanced mechanical properties for advanced engineering applications. 展开更多
关键词 A review of challenges and opportunities in micropillar compression studies in Mg alloys
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