BACKGROUND Bone regeneration is a central focus of regenerative medicine,with applications in orthopedics and dentistry,particularly for treating bone defects caused by trauma,infection,or congenital anomalies.Synthet...BACKGROUND Bone regeneration is a central focus of regenerative medicine,with applications in orthopedics and dentistry,particularly for treating bone defects caused by trauma,infection,or congenital anomalies.Synthetic biomaterials,often combined with fibrin derivatives,offer promising solutions for bone healing and restoration.AIM To Explore the increasingly important role of the association of synthetic biomaterials with fibrin in bone regeneration.METHODS Search terms included:“synthetic biomaterials AND fibrin sealant”,“hydroxyapatite AND fibrin sealant”,“tricalcium phosphate AND fibrin sealant”,and“synthetic biomaterials AND platelet-rich fibrin(PRF)”,resulting in 67 articles.After rigorous screening,21 articles met the inclusion criteria.RESULTS The reviewed studies assessed biomaterials like hydroxyapatite(HA),β-tricalcium phosphate(β-TCP),and fibrin-based products.Key findings highlighted the enhanced osteoconductivity and biocompatibility of HA andβ-TCP,especially when combined with fibrin sealants.These composites show significant potential for improving cellular adhesion,promoting osteogenic differentiation,and accelerating bone regeneration.The antimicrobial properties and structural support for cell growth of certain biomaterials indicate a promising potential for clinical applic-ations.CONCLUSION This systematic review emphasizes the growing role of fibrin-based biomaterials in bone regeneration and urges continued research to improve their clinical use for complex bone defects.展开更多
The regenerative braking energy utilization system(RBEUS)stands as a promising technique for improving the efficiency and power quality of electrified railways.Beyond the vital aspects of energy management and control...The regenerative braking energy utilization system(RBEUS)stands as a promising technique for improving the efficiency and power quality of electrified railways.Beyond the vital aspects of energy management and control strategies,ensuring fault protection is paramount for the secure and steady operation of the traction power supply system(TPSS)integrated with RBEUS.This paper introduces an innovative protection scheme tailored to diverse RBEUS application scenarios.Firstly,fault categories are streamlined into three levels:system,equipment,and warning.Subsequently,a novel multi-port active power differential protection method,aligned with RBEUS operational principles,is crafted to serve as a comprehensive and sensitive main protection.Building upon this foundation,a hierarchical protection structure for RBEUS is established,addressing the intricacies and variations in fault types while boosting anti-disturbance capabilities under faulty conditions.Embracing the principle of railway-oriented safety,a collaborative RBEUS-TPSS protection scheme is put forth.Finally,through simulated scenarios encompassing various fault conditions,the proposed scheme’s feasibility and effectiveness are convincingly validated.展开更多
Braking on low adhesion-coefficient roads,hybrid electric vehicle's motor regenerative torque is switched off to safeguard the normal anti-lock braking system(ABS)fimction.When the ABS control is terminated,the mo...Braking on low adhesion-coefficient roads,hybrid electric vehicle's motor regenerative torque is switched off to safeguard the normal anti-lock braking system(ABS)fimction.When the ABS control is terminated,the motor regenerative braking is readmitted.Aiming at avoiding permanent cycles from hydraulic anti-lock braking to motor regenerative braking,a novel electro-mechanical hybrid anti-lock braking system using fuzzy logic is designed.Different from the traditional single control structure,this system has a two-layered hierarchical structure,The first layer is responsible for harmonious adjustment or interaction between regenerative system and anti-lock braking system.The second layer is responsible for braking torque distribution and adjustment.The closed-loop simulation model is built.Control strategy and method for coordination between regenerative and anti-lock braking are developed.Simulation braking on low adhesion-coefficient roads with fuzzy logic control and real vehicle braking field test are presented.The results from simulating analysis and experiment show braking performance of the vehicle is perfect,harmonious coordination between regenerative and anti-lock braking function,significant amount of braking energy can be recovered and the proposed control strategy and method are effective.展开更多
AIM: To investigate the diagnosis, pathogenesis, natural history, and management of nodular regenerative hyperplasia(NRH) in patients with human immunodeficiency virus(HIV). METHODS: We performed a systematic review o...AIM: To investigate the diagnosis, pathogenesis, natural history, and management of nodular regenerative hyperplasia(NRH) in patients with human immunodeficiency virus(HIV). METHODS: We performed a systematic review of the medical literature regarding NRH in patients with HIV. Inclusion criteria include reports with biopsy proven NRH. We studied the clinical features of NRH, in particular, related to its presenting manifestation and laboratory values. Combinations of the following keywords were implemented: "nodular regenerative hyperplasia", "human immunodeficiency virus", "noncirrhotic portal hypertension", "idiopathic portal hypertension", "cryptogenic liver disease", "highly active antiretroviral therapy" and "didanosine". The bibliographies of these studies were subsequently searched for any additional relevant publications.RESULTS: The clinical presentation of patients with NRH varies from patients being completely asymptomatic to the development of portal hypertension – namely esophageal variceal bleeding and ascites. Liver associated enzymes are generally normal and synthetic function well preserved. There is a strong association between the occurrence of NRH and the use of antiviral therapies such as didanosine. The management of NRH revolves around treating the manifestations of portal hypertension. The prognosis of NRH is generally good since liver function is preserved. A high index of suspicion is required to make a identify NRH. CONCLUSION: The appropriate management of HIVinfected persons with suspected NRH is yet to be outlined. However, NRH is a clinically subtle condition that is difficult to diagnose, and it is important to be able to manage it according to the best available evidence.展开更多
The new regenerative cooling thermal protection system exhibits the multifunctional characteristics of load-carrying and heat exchange cooling,which are fundamental for the lightweight design and thermal protection of...The new regenerative cooling thermal protection system exhibits the multifunctional characteristics of load-carrying and heat exchange cooling,which are fundamental for the lightweight design and thermal protection of hypersonic vehicles.Triply periodic minimal surface(TPMS)is especially suitable for the structural design of the internal cavity of regenerative cooling structures owing to its excellent structural characteristics.In this study,test pieces were manufactured using Ti6Al4V lightweight material.We designed three types of porous test pieces,and the interior was filled with a TPMS lattice(Gyroid,Primitive,I-WP)with a porosity of 30%.All porous test pieces were manufactured via selective laser melting technology.A combination of experiments and finite element simulations were performed to study the selection of the internal cavity structure of the regenerative cooling thermal protection system.Hence,the relationship between the geometry and mechanical properties of a unit cell is established,and the deformation mechanism of the porous unit cell is clarified.Among the three types of porous test pieces,the weight of the test piece filled with the Gyroid unit cell was reduced by 8.21%,the average tensile strength was reduced by 17.7%compared to the solid test piece,while the average tensile strength of the Primitive and I-WP porous test pieces were decreased by 30.5%and 33.3%,respectively.Compared with the other two types of unit cells,Gyroid exhibited better mechanical conductivity characteristics.Its deformation process was characterised by stretching,shearing,and twisting,while the Primitive and I-WP unit cells underwent tensile deformation and tensile and shear deformation,respectively.The finite element predictions in the study agree well with the experimental results.The results can provide a basis for the design of regenerative cooling thermal protection system.展开更多
A high-precision pseudo-noise ranging system is often required in satellite-formation missions. But in an actual PN ranging system, digital signal processing limits the ranging accuracy, only level up with meter-scale...A high-precision pseudo-noise ranging system is often required in satellite-formation missions. But in an actual PN ranging system, digital signal processing limits the ranging accuracy, only level up with meter-scale. Using non-integer chip to sample time ratio, noncommensurate sampling was seen as an effective solution to cope with the drawback of digital effects. However, researchers only paid attention to selecting specific ratios or giving a simulation model to verify the effectiveness of the noncommensurate ratios. A qualitative analysis model is proposed to characterize the relationship between the range accuracy and the noncommensurate sampling parameters. Moreover, a method is also presented which can be used to choose the noncommensurate ratio and the correlation length to get higher phase delay distinguishability and lower range jitter. The simulation results indicate the correctness of our analyses and the optimal ranging accuracy can be up to centimeter-level with the proposed approach.展开更多
Vascular endothelial growth factor（VEGF）in neurodevelopment and regeneration：VEGF is a well-known factor that promotes vascularization and angiogenesis.Besides this it participates in the pathogenesis of several di...Vascular endothelial growth factor（VEGF）in neurodevelopment and regeneration：VEGF is a well-known factor that promotes vascularization and angiogenesis.Besides this it participates in the pathogenesis of several diseases,such as colorectal carcinoma,lung cancer or diabetic retinopathy.Within the last decade,VEGF has been successfully integrated into the treatment of such diseases,for example as a therapy for colorectal cancer with the VEGF-receptor （VEGFR）-inhibitor axitinib.展开更多
Parkinson＇s disease（PD）is the second most common neurodegenerative disease after Alzheimer＇s disease.The etiology of PD is still not completely understood,but the degeneration of dopaminergic（DA）neurons in the s...Parkinson＇s disease（PD）is the second most common neurodegenerative disease after Alzheimer＇s disease.The etiology of PD is still not completely understood,but the degeneration of dopaminergic（DA）neurons in the substantia nigra pars compacta（SNpc）,loss of DA innervation of the striatum,and protein aggregates in the form of Lewy bodies and neurites are its established hallmarks. In addition to α-synuclein accumu- lation in Lewy bodies and neurites, genetic mutations in the genes encoding parkin, PINK, DJ-1, LRRK2 and other proteins are associated with the inherited form of PD. An association study linked also the receptor tyrosine kinase Ret to PD （Meka et al., 2015）. Currently there are only symptomatic treatments available for PD but no cure. Consequently much effort is being made to find neurotrophic and other factors able to stimulate SNpc DA neuron protection and regeneration.展开更多
AIM： To design a classification tool for the histological assessment of hepatocellular carcinoma （HCC）, dysplastic nodules （DN）, and macroregenerative nodules （MRN） in cirrhotic liver. METHODS： Two hundred and...AIM： To design a classification tool for the histological assessment of hepatocellular carcinoma （HCC）, dysplastic nodules （DN）, and macroregenerative nodules （MRN） in cirrhotic liver. METHODS： Two hundred and twelve hepatocellular nodules （106 HCC; 74 IRN, 32 DN） were assessed systematically, quantitatively, and semiquantitatively as appropriate for 10 histological features that have been described as helpful in distinguishing small HCC, DN, and MRN in cirrhotic livers. The data were analyzed by multiple correspondence analysis （MCA）. RESULTS： HCA distributed HCC, DN, and HRN as defined by traditional histological evaluation as well as the individual histological variables, in a ＂malignancy scale＂. Based on the MCA data representation, we created a classification tool, which categorizes an individual nodular lesion as MRN, DN, or HCC based on the balance of all histological features （i.e., vascular invasion, capsular invasion, tumor necrosis, tumor heterogeneity, reticulin loss, capillarization of sinusoids, trabecular thickness, nuclear atypia, and mitotic activity）. The classification tool classified most （83%） of a validation set of 47 nodules in the same way as the routine histological assessment. No discrepandes were present for DN and MRN between the routine histological assignment and the dassification tool. Of 25 HCC assigned by routine assessment in the validation set, 8 were assigned to the DN category by the classification tool. CONCLUSION： We have designed a classification tool for the histological assessment of HCC and its putative precursors in cirrhotic liver. Application of this toolsystematically records histological features of diagnostic importance in the evaluation of small HCC.展开更多
The active suspension has undoubtedly improved the performance of the vehicle,however,the trend of“lowcarbonization,intelligence,and informationization”in the automotive industry has put forward higher and more urge...The active suspension has undoubtedly improved the performance of the vehicle,however,the trend of“lowcarbonization,intelligence,and informationization”in the automotive industry has put forward higher and more urgent requirements for the suspension system.The automotive industry and researchers favor active energy regeneration suspension technology with safety,comfort,and high energy regenerative efficiency.In this paper,we review the research progress of the structure form,optimization method,and control strategy of electromagnetic energy regenerative suspension.Specifically,comparing the pros and cons of the existing technology in solving the contradiction between dynamic performance and energy regeneration.In addition,the development trend of electromagnetic energy regenerative suspension in the field of structure form,optimization method,and control technology prospects.展开更多
In order to fully utilize the regenerative braking energy of metro trains and stabilize the metro DC traction busbar voltage,a hybrid regenerative braking energy recovery system with a dual-mode power management strat...In order to fully utilize the regenerative braking energy of metro trains and stabilize the metro DC traction busbar voltage,a hybrid regenerative braking energy recovery system with a dual-mode power management strategy is proposed.Firstly,the construction of the hybrid regenerative braking energy recovery system is explained.Then,based on the power demand of low-voltage load in metro stations,a dual-mode power management strategy is proposed to allocate the reference power of each system according to the different working conditions,and the control methods of each system are set.Finally,the correctness and effectiveness of the dual-mode strategy are verified through simulation,and the proposed braking energy utilization scheme is compared with other singleform utilization schemes.The results illustrate that the hybrid system with the dual-mode strategy can effectively recycle the regenerative braking energy of metro train and inhibit the busbar voltage fluctuation;the proposed braking energy utilization scheme has certain advantages on energy recovery and DC bus voltage stabilization compared with other single-form schemes;the proposed power management strategy can correctly allocate the reference power of each system with a lower construction cost.展开更多
The networking of microgrids has received significant attention in the form of a smart grid.In this paper,a set of smart railway stations,which is assumed as microgrids,is connected together.It has been tried to manag...The networking of microgrids has received significant attention in the form of a smart grid.In this paper,a set of smart railway stations,which is assumed as microgrids,is connected together.It has been tried to manage the energy exchanged between the networked microgrids to reduce received energy from the utility grid.Also,the operational costs of stations under various conditions decrease by applying the proposed method.The smart railway stations are studied in the presence of photovoltaic(PV)units,energy storage systems(ESSs),and regenerative braking strategies.Studying regenerative braking is one of the essential contributions.Moreover,the stochastic behaviors of the ESS’s initial state of energy and the uncertainty of PV power generation are taken into account through a scenario-based method.The networked microgrid scheme of railway stations(based on coordinated operation and scheduling)and independent operation of railway stations are studied.The proposed method is applied to realistic case studies,including three stations of Line 3 of Tehran Urban and Suburban Railway Operation Company(TUSROC).The rolling stock is simulated in the MATLAB environment.Thus,the coordinated operation of networked microgrids and independent operation of railway stations are optimized in the GAMS environment utilizing mixed-integer linear programming(MILP).展开更多
Regeneration in the central nervous system （CNS） is limited, and CNS damage often leads to cognitive impairment or permanent functional motor and sensory loss. Impaired regenerative capacity is multifactorial and in...Regeneration in the central nervous system （CNS） is limited, and CNS damage often leads to cognitive impairment or permanent functional motor and sensory loss. Impaired regenerative capacity is multifactorial and includes inflammation, loss of the blood-brain barrier, and alteration in the extracellular matrix （ECM）. One of the main problems is the formation of a glial scar and the production of inhibitory ECM, such as proteoglycans, that generates a physical and mechanical barrier, impeding axonal regrowth （Figure 1A）.展开更多
A combined system model is proposed including a molten carbonate fuel cell(MCFC),a graphene thermionic converter(GTIC)and thermally regenerative electrochemical cycles(TRECs).The expressions for power output,energy ef...A combined system model is proposed including a molten carbonate fuel cell(MCFC),a graphene thermionic converter(GTIC)and thermally regenerative electrochemical cycles(TRECs).The expressions for power output,energy efficiency of the subsystems and the couple system are formulated by considering several irreversible losses.Energy conservation equations between the subsystems are achieved leaned on the first law of thermodynamics.The optimum operating ranges for the combined system are determined compared with the MCFC system.Results reveal that the peak power output density(POD)and the corresponding energy efficiency are 28.22%and 10.76%higher than that of the single MCFC system,respectively.The effects of five designing parameters on the power density and energy efficiency of the MCFC/GTIC/TRECs model are also investigated and discussed.展开更多
This paper describes the optimal design of a Cathode blower used for a building fuel cell system. The Cathode air blower has a regenerative blower type. Two design variables, extension angle and number of impeller bla...This paper describes the optimal design of a Cathode blower used for a building fuel cell system. The Cathode air blower has a regenerative blower type. Two design variables, extension angle and number of impeller blade are introduced to enhance the blower performance. Pressure and efficiency of the blower are selected as an object function, and the optimal design is performed by a response surface method. Three-dimensional Navier-Stokes equations are introduced to analyze the performance and internal flow of the blower and to find the value of object function for the training data. Throughout the design optimization, it is found that an extension angle is effective to increase blower efficiency in the blower. The pressure rise for the optimal blower is successfully increased up to 3.17% compared with that of reference one at the design flow rate. It is noted that low velocity region disturbs to make strong recirculation flow in the each blade passage, thus increases local pressure loss. Detailed flow field inside a regenerative blower is also analyzed and compared.展开更多
In recent years,the progression of stem cell therapies has shown great promise in advancing the nascent field of regenerative medicine.Considering the non-regenerative nature of the mature central nervous system,the c...In recent years,the progression of stem cell therapies has shown great promise in advancing the nascent field of regenerative medicine.Considering the non-regenerative nature of the mature central nervous system,the concept that“blank”cells could be reprogrammed and functionally integrated into host neural networks remained intriguing.Previous work has also demonstrated the ability of such cells to stimulate intrinsic growth programs in post-mitotic cells,such as neurons.While embryonic stem cells demonstrated great potential in treating central nervous system pathologies,ethical and technical concerns remained.These barriers,along with the clear necessity for this type of treatment,ultimately prompted the advent of induced pluripotent stem cells.The advantage of pluripotent cells in central nervous system regeneration is multifaceted,permitting differentiation into neural stem cells,neural progenitor cells,glia,and various neuronal subpopulations.The precise spatiotemporal application of extrinsic growth factors in vitro,in addition to microenvironmental signaling in vivo,influences the efficiency of this directed differentiation.While the pluri-or multipotency of these cells is appealing,it also poses the risk of unregulated differentiation and teratoma formation.Cells of the neuroectodermal lineage,such as neuronal subpopulations and glia,have been explored with varying degrees of success.Although the risk of cancer or teratoma formation is greatly reduced,each subpopulation varies in effectiveness and is influenced by a myriad of factors,such as the timing of the transplant,pathology type,and the ratio of accompanying progenitor cells.Furthermore,successful transplantation requires innovative approaches to develop delivery vectors that can mitigate cell death and support integration.Lastly,host immune responses to allogeneic grafts must be thoroughly characterized and further developed to reduce the need for immunosuppression.Translation to a clinical setting will involve careful consideration when assessing both physiologic and functional outcomes.This review will highlight both successes and challenges faced when using human induced pluripotent stem cell-derived cell transplantation therapies to promote endogenous regeneration.展开更多
In the context of the“dual carbon”goals,to address issues such as high energy consumption,high costs,and low power quality in the rapid development of electrified railways,this study focused on the China Railways Hi...In the context of the“dual carbon”goals,to address issues such as high energy consumption,high costs,and low power quality in the rapid development of electrified railways,this study focused on the China Railways High-Speed 5 Electric Multiple Unit and proposed a mathematical model and capacity optimization method for an onboard energy storage system using lithium batteries and supercapacitors as storage media.Firstly,considering the electrical characteristics,weight,and volume of the storage media,a mathematical model of the energy storage system was established.Secondly,to tackle problems related to energy consumption and power quality,an energy management strategy was proposed that comprehensively considers peak shaving and valley filling and power quality by controlling the charge/discharge thresholds of the storage system.Thecapacity optimization adopted a bilevel programming model,with the series/parallel number of storage modules as variables,considering constraints imposed by the Direct Current to Direct Current converter,train load,and space.An improved Particle Swarm Optimization algorithm and linear programming solver were used to solve specific cases.The results show that the proposed onboard energy storage system can effectively achieve energy savings,reduce consumption,and improve power qualitywhile meeting the load and space limitations of the train.展开更多
Due to the complex high-temperature characteristics of hydrocarbon fuel,the research on the long-term working process of parallel channel structure under variable working conditions,especially under high heat-mass rat...Due to the complex high-temperature characteristics of hydrocarbon fuel,the research on the long-term working process of parallel channel structure under variable working conditions,especially under high heat-mass ratio,has not been systematically carried out.In this paper,the heat transfer and flow characteristics of related high temperature fuels are studied by using typical engine parallel channel structure.Through numeri⁃cal simulation and systematic experimental verification,the flow and heat transfer characteristics of parallel chan⁃nels under typical working conditions are obtained,and the effectiveness of high-precision calculation method is preliminarily established.It is known that the stable time required for hot start of regenerative cooling engine is about 50 s,and the flow resistance of parallel channel structure first increases and then decreases with the in⁃crease of equivalence ratio(The following equivalence ratio is expressed byΦ),and there is a flow resistance peak in the range ofΦ=0.5~0.8.This is mainly caused by the coupling effect of high temperature physical proper⁃ties,flow rate and pressure of fuel in parallel channels.At the same time,the cooling and heat transfer character⁃istics of parallel channels under some conditions of high heat-mass ratio are obtained,and the main factors affect⁃ing the heat transfer of parallel channels such as improving surface roughness and strengthening heat transfer are mastered.In the experiment,whenΦis less than 0.9,the phenomenon of local heat transfer enhancement and deterioration can be obviously observed,and the temperature rise of local structures exceeds 200℃,which is the risk of structural damage.Therefore,the reliability of long-term parallel channel structure under the condition of high heat-mass ratio should be fully considered in structural design.展开更多
A unitized regenerative fuel cell(URFC)is a device that may function reversibly as either a fuel cell(FC)or water elec-trolysis(WE).An important component of this device is the Membrane electrode assembly(MEA).Therefo...A unitized regenerative fuel cell(URFC)is a device that may function reversibly as either a fuel cell(FC)or water elec-trolysis(WE).An important component of this device is the Membrane electrode assembly(MEA).Therefore,this study aimed to compare the performance outcomes of MEA using electrodes with single and three catalyst layers.This study measured Electrochemical Surface Area(ECSA),Electrochemical Impedance Spectroscopy(EIS),X-ray Diffraction analysis(XRD),and X-ray Fluorescence(XRF).Furthermore,the round-trip efficiency(RTE)of the MEA,as w ell as the performance in FC and WE mode,was measured.In comparison,The ECSA values of Pt-Ru/C and Pt/C with three catalyst layers were higher than the single catalyst layer.This result was supported by electrode characterization data for XRD and XRF.The respective electrical conductivity values of Pt-Ru/C and Pt/C with three catalyst layers are also higher than the single cata-lyst layer,and the performance of URFC using MEA with three catalyst layers has the highest value of RTE among the MEA performances of URFC,which is 100%at a current density of 4 mA·cm-2.展开更多
BACKGROUND Incisional hernias are a common complication of previous surgeries and remain a persistent issue in clinical practice,posing a significant burden on healthcare systems despite advances in education and tech...BACKGROUND Incisional hernias are a common complication of previous surgeries and remain a persistent issue in clinical practice,posing a significant burden on healthcare systems despite advances in education and technology.Surgical techniques,primarily involving the use of mesh to cover the abdominal wall gap,are widely used as a standard intervention strategy.AIM To examine the regeneration of the aponeurosis defect in the anterior abdominal wall in rats using regenerative mimetic factors of the extracellular matrix[ReGeneraTing Agent(RGTA)],adipose tissue micrografts(ATM),and platelet rich plasma(PRP)as regenerative agents.METHODS Regenerative agents such as RGTA,ATM,and PRP are gaining popularity.ATM involves autologous adipose tissue cells with mesenchymal stem cell markers and a high percentage of stromal vascular fraction cells.RGTAs are heparan sulfate(HS)mimetics that replace degraded HSs in damaged tissue,enhancing the quality and speed of repair.PRP is a concentrated plasma preparation containing seven fundamental proteins responsible for tissue production.An acellular dermal matrix is a biological implant free of cellular or antigenic components,making it an excellent material for reconstructive surgery.Polyglactin is a synthetic,absorbable mesh that loses 50%of its strength after fourteen days,providing initial support for new tissue regeneration before being completely absorbed.RESULTS Rats will undergo a laparotomy with a precise 2 cm by 2 cm excision of the anterior abdominal wall fascia below the umbilicus.They will be divided into sixteen groups,each receiving different combinations of regenerative factor injections into the denervated area in both non-contaminated and contaminated environments.A collagenelastin matrix will be used to join the aponeurosis edges,with an absorbable polyglactin mesh anchored over it.Samples will be taken for macroscopic,histological,and immunohistochemical evaluation of tissue regeneration.CONCLUSION Our study aims to demonstrate how these factors promote cell proliferation and healing of the denervated anterior abdominal wall,potentially reducing the frequency and complications of incisional hernias.This approach could offer a more economical and efficient treatment option compared to current costly methods.展开更多
文摘BACKGROUND Bone regeneration is a central focus of regenerative medicine,with applications in orthopedics and dentistry,particularly for treating bone defects caused by trauma,infection,or congenital anomalies.Synthetic biomaterials,often combined with fibrin derivatives,offer promising solutions for bone healing and restoration.AIM To Explore the increasingly important role of the association of synthetic biomaterials with fibrin in bone regeneration.METHODS Search terms included:“synthetic biomaterials AND fibrin sealant”,“hydroxyapatite AND fibrin sealant”,“tricalcium phosphate AND fibrin sealant”,and“synthetic biomaterials AND platelet-rich fibrin(PRF)”,resulting in 67 articles.After rigorous screening,21 articles met the inclusion criteria.RESULTS The reviewed studies assessed biomaterials like hydroxyapatite(HA),β-tricalcium phosphate(β-TCP),and fibrin-based products.Key findings highlighted the enhanced osteoconductivity and biocompatibility of HA andβ-TCP,especially when combined with fibrin sealants.These composites show significant potential for improving cellular adhesion,promoting osteogenic differentiation,and accelerating bone regeneration.The antimicrobial properties and structural support for cell growth of certain biomaterials indicate a promising potential for clinical applic-ations.CONCLUSION This systematic review emphasizes the growing role of fibrin-based biomaterials in bone regeneration and urges continued research to improve their clinical use for complex bone defects.
基金supported by the National Natural Science Foundation of China(Nos.52107126 and52077179)the Key Regional Innovation and Development Joint Fund Project(No.2023YFB2303901)the funding of Chengdu Guojia Electrical Engineering Co.,Ltd.(No.NEEC-2022-B11).
文摘The regenerative braking energy utilization system(RBEUS)stands as a promising technique for improving the efficiency and power quality of electrified railways.Beyond the vital aspects of energy management and control strategies,ensuring fault protection is paramount for the secure and steady operation of the traction power supply system(TPSS)integrated with RBEUS.This paper introduces an innovative protection scheme tailored to diverse RBEUS application scenarios.Firstly,fault categories are streamlined into three levels:system,equipment,and warning.Subsequently,a novel multi-port active power differential protection method,aligned with RBEUS operational principles,is crafted to serve as a comprehensive and sensitive main protection.Building upon this foundation,a hierarchical protection structure for RBEUS is established,addressing the intricacies and variations in fault types while boosting anti-disturbance capabilities under faulty conditions.Embracing the principle of railway-oriented safety,a collaborative RBEUS-TPSS protection scheme is put forth.Finally,through simulated scenarios encompassing various fault conditions,the proposed scheme’s feasibility and effectiveness are convincingly validated.
基金supported by National Development and Reform Commission of China(Grant No.2005934)
文摘Braking on low adhesion-coefficient roads,hybrid electric vehicle's motor regenerative torque is switched off to safeguard the normal anti-lock braking system(ABS)fimction.When the ABS control is terminated,the motor regenerative braking is readmitted.Aiming at avoiding permanent cycles from hydraulic anti-lock braking to motor regenerative braking,a novel electro-mechanical hybrid anti-lock braking system using fuzzy logic is designed.Different from the traditional single control structure,this system has a two-layered hierarchical structure,The first layer is responsible for harmonious adjustment or interaction between regenerative system and anti-lock braking system.The second layer is responsible for braking torque distribution and adjustment.The closed-loop simulation model is built.Control strategy and method for coordination between regenerative and anti-lock braking are developed.Simulation braking on low adhesion-coefficient roads with fuzzy logic control and real vehicle braking field test are presented.The results from simulating analysis and experiment show braking performance of the vehicle is perfect,harmonious coordination between regenerative and anti-lock braking function,significant amount of braking energy can be recovered and the proposed control strategy and method are effective.
文摘AIM: To investigate the diagnosis, pathogenesis, natural history, and management of nodular regenerative hyperplasia(NRH) in patients with human immunodeficiency virus(HIV). METHODS: We performed a systematic review of the medical literature regarding NRH in patients with HIV. Inclusion criteria include reports with biopsy proven NRH. We studied the clinical features of NRH, in particular, related to its presenting manifestation and laboratory values. Combinations of the following keywords were implemented: "nodular regenerative hyperplasia", "human immunodeficiency virus", "noncirrhotic portal hypertension", "idiopathic portal hypertension", "cryptogenic liver disease", "highly active antiretroviral therapy" and "didanosine". The bibliographies of these studies were subsequently searched for any additional relevant publications.RESULTS: The clinical presentation of patients with NRH varies from patients being completely asymptomatic to the development of portal hypertension – namely esophageal variceal bleeding and ascites. Liver associated enzymes are generally normal and synthetic function well preserved. There is a strong association between the occurrence of NRH and the use of antiviral therapies such as didanosine. The management of NRH revolves around treating the manifestations of portal hypertension. The prognosis of NRH is generally good since liver function is preserved. A high index of suspicion is required to make a identify NRH. CONCLUSION: The appropriate management of HIVinfected persons with suspected NRH is yet to be outlined. However, NRH is a clinically subtle condition that is difficult to diagnose, and it is important to be able to manage it according to the best available evidence.
基金support from the National Natural Science Foundation of China(NSFC,Project Nos.91860136 and 51801231)the Key R&D Plan of Guangdong Province(Grant No.2018B090905001)the Key Science and Technology project of Shaanxi Province(Grant No.2018zdzx01-04-01).
文摘The new regenerative cooling thermal protection system exhibits the multifunctional characteristics of load-carrying and heat exchange cooling,which are fundamental for the lightweight design and thermal protection of hypersonic vehicles.Triply periodic minimal surface(TPMS)is especially suitable for the structural design of the internal cavity of regenerative cooling structures owing to its excellent structural characteristics.In this study,test pieces were manufactured using Ti6Al4V lightweight material.We designed three types of porous test pieces,and the interior was filled with a TPMS lattice(Gyroid,Primitive,I-WP)with a porosity of 30%.All porous test pieces were manufactured via selective laser melting technology.A combination of experiments and finite element simulations were performed to study the selection of the internal cavity structure of the regenerative cooling thermal protection system.Hence,the relationship between the geometry and mechanical properties of a unit cell is established,and the deformation mechanism of the porous unit cell is clarified.Among the three types of porous test pieces,the weight of the test piece filled with the Gyroid unit cell was reduced by 8.21%,the average tensile strength was reduced by 17.7%compared to the solid test piece,while the average tensile strength of the Primitive and I-WP porous test pieces were decreased by 30.5%and 33.3%,respectively.Compared with the other two types of unit cells,Gyroid exhibited better mechanical conductivity characteristics.Its deformation process was characterised by stretching,shearing,and twisting,while the Primitive and I-WP unit cells underwent tensile deformation and tensile and shear deformation,respectively.The finite element predictions in the study agree well with the experimental results.The results can provide a basis for the design of regenerative cooling thermal protection system.
基金Project(60904090) supported by the National Natural Science Foundation of China
文摘A high-precision pseudo-noise ranging system is often required in satellite-formation missions. But in an actual PN ranging system, digital signal processing limits the ranging accuracy, only level up with meter-scale. Using non-integer chip to sample time ratio, noncommensurate sampling was seen as an effective solution to cope with the drawback of digital effects. However, researchers only paid attention to selecting specific ratios or giving a simulation model to verify the effectiveness of the noncommensurate ratios. A qualitative analysis model is proposed to characterize the relationship between the range accuracy and the noncommensurate sampling parameters. Moreover, a method is also presented which can be used to choose the noncommensurate ratio and the correlation length to get higher phase delay distinguishability and lower range jitter. The simulation results indicate the correctness of our analyses and the optimal ranging accuracy can be up to centimeter-level with the proposed approach.
基金the Heinrich and Alma Vogelsang Foundation for financial support in the form of a graduation scholarship
文摘Vascular endothelial growth factor（VEGF）in neurodevelopment and regeneration：VEGF is a well-known factor that promotes vascularization and angiogenesis.Besides this it participates in the pathogenesis of several diseases,such as colorectal carcinoma,lung cancer or diabetic retinopathy.Within the last decade,VEGF has been successfully integrated into the treatment of such diseases,for example as a therapy for colorectal cancer with the VEGF-receptor （VEGFR）-inhibitor axitinib.
基金supported by grants from the DFG (KR 3529/4-1 to ERK)the town of Hamburg (Lexi to ERK)
文摘Parkinson＇s disease（PD）is the second most common neurodegenerative disease after Alzheimer＇s disease.The etiology of PD is still not completely understood,but the degeneration of dopaminergic（DA）neurons in the substantia nigra pars compacta（SNpc）,loss of DA innervation of the striatum,and protein aggregates in the form of Lewy bodies and neurites are its established hallmarks. In addition to α-synuclein accumu- lation in Lewy bodies and neurites, genetic mutations in the genes encoding parkin, PINK, DJ-1, LRRK2 and other proteins are associated with the inherited form of PD. An association study linked also the receptor tyrosine kinase Ret to PD （Meka et al., 2015）. Currently there are only symptomatic treatments available for PD but no cure. Consequently much effort is being made to find neurotrophic and other factors able to stimulate SNpc DA neuron protection and regeneration.
文摘AIM： To design a classification tool for the histological assessment of hepatocellular carcinoma （HCC）, dysplastic nodules （DN）, and macroregenerative nodules （MRN） in cirrhotic liver. METHODS： Two hundred and twelve hepatocellular nodules （106 HCC; 74 IRN, 32 DN） were assessed systematically, quantitatively, and semiquantitatively as appropriate for 10 histological features that have been described as helpful in distinguishing small HCC, DN, and MRN in cirrhotic livers. The data were analyzed by multiple correspondence analysis （MCA）. RESULTS： HCA distributed HCC, DN, and HRN as defined by traditional histological evaluation as well as the individual histological variables, in a ＂malignancy scale＂. Based on the MCA data representation, we created a classification tool, which categorizes an individual nodular lesion as MRN, DN, or HCC based on the balance of all histological features （i.e., vascular invasion, capsular invasion, tumor necrosis, tumor heterogeneity, reticulin loss, capillarization of sinusoids, trabecular thickness, nuclear atypia, and mitotic activity）. The classification tool classified most （83%） of a validation set of 47 nodules in the same way as the routine histological assessment. No discrepandes were present for DN and MRN between the routine histological assignment and the dassification tool. Of 25 HCC assigned by routine assessment in the validation set, 8 were assigned to the DN category by the classification tool. CONCLUSION： We have designed a classification tool for the histological assessment of HCC and its putative precursors in cirrhotic liver. Application of this toolsystematically records histological features of diagnostic importance in the evaluation of small HCC.
基金supported by the National Natural Science Foundation of China (51975341,51875326,and 51905319)Shandong Provincial Natural Science Foundation,China (ZR2021QE180)+1 种基金the Young Technology Talent Supporting Project of Shandong Province (2021KJ083)SDUT&Zhangdian District Integration Development Project (2021JSCG0015).
文摘The active suspension has undoubtedly improved the performance of the vehicle,however,the trend of“lowcarbonization,intelligence,and informationization”in the automotive industry has put forward higher and more urgent requirements for the suspension system.The automotive industry and researchers favor active energy regeneration suspension technology with safety,comfort,and high energy regenerative efficiency.In this paper,we review the research progress of the structure form,optimization method,and control strategy of electromagnetic energy regenerative suspension.Specifically,comparing the pros and cons of the existing technology in solving the contradiction between dynamic performance and energy regeneration.In addition,the development trend of electromagnetic energy regenerative suspension in the field of structure form,optimization method,and control technology prospects.
基金funded by Project supported by the Natural Science Foundation of Gansu Province,China(Grant No.22JR5RA318).
文摘In order to fully utilize the regenerative braking energy of metro trains and stabilize the metro DC traction busbar voltage,a hybrid regenerative braking energy recovery system with a dual-mode power management strategy is proposed.Firstly,the construction of the hybrid regenerative braking energy recovery system is explained.Then,based on the power demand of low-voltage load in metro stations,a dual-mode power management strategy is proposed to allocate the reference power of each system according to the different working conditions,and the control methods of each system are set.Finally,the correctness and effectiveness of the dual-mode strategy are verified through simulation,and the proposed braking energy utilization scheme is compared with other singleform utilization schemes.The results illustrate that the hybrid system with the dual-mode strategy can effectively recycle the regenerative braking energy of metro train and inhibit the busbar voltage fluctuation;the proposed braking energy utilization scheme has certain advantages on energy recovery and DC bus voltage stabilization compared with other single-form schemes;the proposed power management strategy can correctly allocate the reference power of each system with a lower construction cost.
文摘The networking of microgrids has received significant attention in the form of a smart grid.In this paper,a set of smart railway stations,which is assumed as microgrids,is connected together.It has been tried to manage the energy exchanged between the networked microgrids to reduce received energy from the utility grid.Also,the operational costs of stations under various conditions decrease by applying the proposed method.The smart railway stations are studied in the presence of photovoltaic(PV)units,energy storage systems(ESSs),and regenerative braking strategies.Studying regenerative braking is one of the essential contributions.Moreover,the stochastic behaviors of the ESS’s initial state of energy and the uncertainty of PV power generation are taken into account through a scenario-based method.The networked microgrid scheme of railway stations(based on coordinated operation and scheduling)and independent operation of railway stations are studied.The proposed method is applied to realistic case studies,including three stations of Line 3 of Tehran Urban and Suburban Railway Operation Company(TUSROC).The rolling stock is simulated in the MATLAB environment.Thus,the coordinated operation of networked microgrids and independent operation of railway stations are optimized in the GAMS environment utilizing mixed-integer linear programming(MILP).
文摘Regeneration in the central nervous system （CNS） is limited, and CNS damage often leads to cognitive impairment or permanent functional motor and sensory loss. Impaired regenerative capacity is multifactorial and includes inflammation, loss of the blood-brain barrier, and alteration in the extracellular matrix （ECM）. One of the main problems is the formation of a glial scar and the production of inhibitory ECM, such as proteoglycans, that generates a physical and mechanical barrier, impeding axonal regrowth （Figure 1A）.
文摘A combined system model is proposed including a molten carbonate fuel cell(MCFC),a graphene thermionic converter(GTIC)and thermally regenerative electrochemical cycles(TRECs).The expressions for power output,energy efficiency of the subsystems and the couple system are formulated by considering several irreversible losses.Energy conservation equations between the subsystems are achieved leaned on the first law of thermodynamics.The optimum operating ranges for the combined system are determined compared with the MCFC system.Results reveal that the peak power output density(POD)and the corresponding energy efficiency are 28.22%and 10.76%higher than that of the single MCFC system,respectively.The effects of five designing parameters on the power density and energy efficiency of the MCFC/GTIC/TRECs model are also investigated and discussed.
文摘This paper describes the optimal design of a Cathode blower used for a building fuel cell system. The Cathode air blower has a regenerative blower type. Two design variables, extension angle and number of impeller blade are introduced to enhance the blower performance. Pressure and efficiency of the blower are selected as an object function, and the optimal design is performed by a response surface method. Three-dimensional Navier-Stokes equations are introduced to analyze the performance and internal flow of the blower and to find the value of object function for the training data. Throughout the design optimization, it is found that an extension angle is effective to increase blower efficiency in the blower. The pressure rise for the optimal blower is successfully increased up to 3.17% compared with that of reference one at the design flow rate. It is noted that low velocity region disturbs to make strong recirculation flow in the each blade passage, thus increases local pressure loss. Detailed flow field inside a regenerative blower is also analyzed and compared.
基金supported by Ohio State Start Up FundNational Institutes of Health(NIH)+12 种基金Department of Defense(DoD)Wings for Life Spinal Cord Research Foundation,Wings for Life Spinal Cord Research Foundation(Austria)California Institute of Regenerative Medicine(CIRM)International Spinal Research Trust(United Kingdom)Stanford University Bio-X Program Interdisciplinary Initiatives Seed Grant IIP-7Dennis Chan FoundationKlein Family FundLucile Packard Foundation for Children's HealthStanford Institute for Neuro-Innovation and Translational Neurosciences(SINTN)Saunders Family Neuroscience FundJames Doty Neurosurgery FundHearst Neuroscience FundEileen Bond Research Fund(to GP)。
文摘In recent years,the progression of stem cell therapies has shown great promise in advancing the nascent field of regenerative medicine.Considering the non-regenerative nature of the mature central nervous system,the concept that“blank”cells could be reprogrammed and functionally integrated into host neural networks remained intriguing.Previous work has also demonstrated the ability of such cells to stimulate intrinsic growth programs in post-mitotic cells,such as neurons.While embryonic stem cells demonstrated great potential in treating central nervous system pathologies,ethical and technical concerns remained.These barriers,along with the clear necessity for this type of treatment,ultimately prompted the advent of induced pluripotent stem cells.The advantage of pluripotent cells in central nervous system regeneration is multifaceted,permitting differentiation into neural stem cells,neural progenitor cells,glia,and various neuronal subpopulations.The precise spatiotemporal application of extrinsic growth factors in vitro,in addition to microenvironmental signaling in vivo,influences the efficiency of this directed differentiation.While the pluri-or multipotency of these cells is appealing,it also poses the risk of unregulated differentiation and teratoma formation.Cells of the neuroectodermal lineage,such as neuronal subpopulations and glia,have been explored with varying degrees of success.Although the risk of cancer or teratoma formation is greatly reduced,each subpopulation varies in effectiveness and is influenced by a myriad of factors,such as the timing of the transplant,pathology type,and the ratio of accompanying progenitor cells.Furthermore,successful transplantation requires innovative approaches to develop delivery vectors that can mitigate cell death and support integration.Lastly,host immune responses to allogeneic grafts must be thoroughly characterized and further developed to reduce the need for immunosuppression.Translation to a clinical setting will involve careful consideration when assessing both physiologic and functional outcomes.This review will highlight both successes and challenges faced when using human induced pluripotent stem cell-derived cell transplantation therapies to promote endogenous regeneration.
基金funded by the National Natural Science Foundation of China(52167013)the Key Program of Natural Science Foundation of Gansu Province(24JRRA225)Natural Science Foundation of Gansu Province(23JRRA891).
文摘In the context of the“dual carbon”goals,to address issues such as high energy consumption,high costs,and low power quality in the rapid development of electrified railways,this study focused on the China Railways High-Speed 5 Electric Multiple Unit and proposed a mathematical model and capacity optimization method for an onboard energy storage system using lithium batteries and supercapacitors as storage media.Firstly,considering the electrical characteristics,weight,and volume of the storage media,a mathematical model of the energy storage system was established.Secondly,to tackle problems related to energy consumption and power quality,an energy management strategy was proposed that comprehensively considers peak shaving and valley filling and power quality by controlling the charge/discharge thresholds of the storage system.Thecapacity optimization adopted a bilevel programming model,with the series/parallel number of storage modules as variables,considering constraints imposed by the Direct Current to Direct Current converter,train load,and space.An improved Particle Swarm Optimization algorithm and linear programming solver were used to solve specific cases.The results show that the proposed onboard energy storage system can effectively achieve energy savings,reduce consumption,and improve power qualitywhile meeting the load and space limitations of the train.
文摘Due to the complex high-temperature characteristics of hydrocarbon fuel,the research on the long-term working process of parallel channel structure under variable working conditions,especially under high heat-mass ratio,has not been systematically carried out.In this paper,the heat transfer and flow characteristics of related high temperature fuels are studied by using typical engine parallel channel structure.Through numeri⁃cal simulation and systematic experimental verification,the flow and heat transfer characteristics of parallel chan⁃nels under typical working conditions are obtained,and the effectiveness of high-precision calculation method is preliminarily established.It is known that the stable time required for hot start of regenerative cooling engine is about 50 s,and the flow resistance of parallel channel structure first increases and then decreases with the in⁃crease of equivalence ratio(The following equivalence ratio is expressed byΦ),and there is a flow resistance peak in the range ofΦ=0.5~0.8.This is mainly caused by the coupling effect of high temperature physical proper⁃ties,flow rate and pressure of fuel in parallel channels.At the same time,the cooling and heat transfer character⁃istics of parallel channels under some conditions of high heat-mass ratio are obtained,and the main factors affect⁃ing the heat transfer of parallel channels such as improving surface roughness and strengthening heat transfer are mastered.In the experiment,whenΦis less than 0.9,the phenomenon of local heat transfer enhancement and deterioration can be obviously observed,and the temperature rise of local structures exceeds 200℃,which is the risk of structural damage.Therefore,the reliability of long-term parallel channel structure under the condition of high heat-mass ratio should be fully considered in structural design.
基金support from the Ministry of Higher Education Malaysia under grant HICOE-2023-005.
文摘A unitized regenerative fuel cell(URFC)is a device that may function reversibly as either a fuel cell(FC)or water elec-trolysis(WE).An important component of this device is the Membrane electrode assembly(MEA).Therefore,this study aimed to compare the performance outcomes of MEA using electrodes with single and three catalyst layers.This study measured Electrochemical Surface Area(ECSA),Electrochemical Impedance Spectroscopy(EIS),X-ray Diffraction analysis(XRD),and X-ray Fluorescence(XRF).Furthermore,the round-trip efficiency(RTE)of the MEA,as w ell as the performance in FC and WE mode,was measured.In comparison,The ECSA values of Pt-Ru/C and Pt/C with three catalyst layers were higher than the single catalyst layer.This result was supported by electrode characterization data for XRD and XRF.The respective electrical conductivity values of Pt-Ru/C and Pt/C with three catalyst layers are also higher than the single cata-lyst layer,and the performance of URFC using MEA with three catalyst layers has the highest value of RTE among the MEA performances of URFC,which is 100%at a current density of 4 mA·cm-2.
文摘BACKGROUND Incisional hernias are a common complication of previous surgeries and remain a persistent issue in clinical practice,posing a significant burden on healthcare systems despite advances in education and technology.Surgical techniques,primarily involving the use of mesh to cover the abdominal wall gap,are widely used as a standard intervention strategy.AIM To examine the regeneration of the aponeurosis defect in the anterior abdominal wall in rats using regenerative mimetic factors of the extracellular matrix[ReGeneraTing Agent(RGTA)],adipose tissue micrografts(ATM),and platelet rich plasma(PRP)as regenerative agents.METHODS Regenerative agents such as RGTA,ATM,and PRP are gaining popularity.ATM involves autologous adipose tissue cells with mesenchymal stem cell markers and a high percentage of stromal vascular fraction cells.RGTAs are heparan sulfate(HS)mimetics that replace degraded HSs in damaged tissue,enhancing the quality and speed of repair.PRP is a concentrated plasma preparation containing seven fundamental proteins responsible for tissue production.An acellular dermal matrix is a biological implant free of cellular or antigenic components,making it an excellent material for reconstructive surgery.Polyglactin is a synthetic,absorbable mesh that loses 50%of its strength after fourteen days,providing initial support for new tissue regeneration before being completely absorbed.RESULTS Rats will undergo a laparotomy with a precise 2 cm by 2 cm excision of the anterior abdominal wall fascia below the umbilicus.They will be divided into sixteen groups,each receiving different combinations of regenerative factor injections into the denervated area in both non-contaminated and contaminated environments.A collagenelastin matrix will be used to join the aponeurosis edges,with an absorbable polyglactin mesh anchored over it.Samples will be taken for macroscopic,histological,and immunohistochemical evaluation of tissue regeneration.CONCLUSION Our study aims to demonstrate how these factors promote cell proliferation and healing of the denervated anterior abdominal wall,potentially reducing the frequency and complications of incisional hernias.This approach could offer a more economical and efficient treatment option compared to current costly methods.
