This study investigates prescribed-time position tracking control for electromagnetic satellite formations subject to model uncertainties and external disturbances.Using the Clohessy-Wiltshire equations as the relativ...This study investigates prescribed-time position tracking control for electromagnetic satellite formations subject to model uncertainties and external disturbances.Using the Clohessy-Wiltshire equations as the relative motion dynamics model,a prescribed time output feedback control strategy is proposed.A prescribed-time extended state observer is designed to estimate the relative velocity and external disturbances.The disturbance estimates are then used as the feedforward component of the controller.Building on this framework,a novel prescribed-time active disturbance rejection control strategy for position tracking is developed via a backstepping control design.The convergence of the extended state observer and the stability of the closed-loop system are rigorously analyzed using Lyapunov stability theory.Numerical simulations are performed to validate the effectiveness of the proposed controller.展开更多
1 Introduction Recently,the increasing demand for advanced telecommunication systems has spurred extensive research into bandpass filters(BPFs),with particular emphasis on miniaturization,reduction of insertion loss(I...1 Introduction Recently,the increasing demand for advanced telecommunication systems has spurred extensive research into bandpass filters(BPFs),with particular emphasis on miniaturization,reduction of insertion loss(IL),and enhancement of upper stopband rejection(Huang et al.,2021;Snyder et al.,2021;Lin et al.,2023;Zeng et al.,2023).展开更多
Antibody-mediated rejection(AMR)remains a leading cause of kidney allograft failure,posing significant clinical and economic challenges.Donor-specific antibodies against human leukocyte antigens or non-human leukocyte...Antibody-mediated rejection(AMR)remains a leading cause of kidney allograft failure,posing significant clinical and economic challenges.Donor-specific antibodies against human leukocyte antigens or non-human leukocyte antigens are critical risk factors for AMR and graft loss.The diagnostic criteria and classification of AMR have evolved considerably over the past three decades,driven largely by the Banff classification.The latest Banff 2022 classification introduced two additional subcategories of“microvascular inflammation,donor-specific antibody-negative,C4d-negative”and“probable AMR”.Traditionally,graft monitoring has relied on non-specific markers such as serum creatinine and proteinuria,and the invasive biopsies.Noninvasive tools using blood and urine biomarkers,including cellular assays and molecular profiling,are increasingly being investigated.Technologies such as the Molecular Microscope Diagnostic System show promise,with studies reporting 80%sensitivity and 90%specificity in detecting AMR.Treatment of AMR remains inconsistent.Recent advances,including CD38 antibodies,have demonstrated up to 60%efficacy in reversing AMR,while complement inhibition shows potential in severe early cases.Ongoing clinical trials evaluating high-dose intravenous immunoglobulin,efgartigimod,fostamatinib,and other novel therapies aim to expand treatment options.These developments highlight the need for well-designed clinical trials to validate biomarkers and therapies and to improve long-term outcomes for kidney transplant recipients.展开更多
The arms race between avian brood parasites and their hosts provides a classic model for studying coevolution.In one of the most widespread obligate brood parasites,the Common Cuckoo(Cuculus canorus),chicks typically ...The arms race between avian brood parasites and their hosts provides a classic model for studying coevolution.In one of the most widespread obligate brood parasites,the Common Cuckoo(Cuculus canorus),chicks typically evict all host progeny(eggs and nestlings)from the nest cup,resulting in complete reproductive failure for the host.Host parents of Common Cuckoos could thus potentially benefit from retrieving evicted eggs and nestlings into the nest cup.However,whether hosts of the Common Cuckoo exhibit such retrieval behavior has been scarcely studied.In this study,we experimentally investigated the occurrence of retrieval in a nestbox-breeding population of Daurian Redstarts(Phoenicurus auroreus),a common cavity-nesting host of the Common Cuckoo.To test the redstarts'response to an egg or a nestling outside the nest cup,we experimentally placed either a conspecific egg,a model cuckoo egg,or a redstart nestling near the rim of the nest cup.We found that redstarts never showed retrieval behavior of either eggs or nestlings.All hosts ignored the experimental nestling and conspecific egg,but most ejected the model cuckoo egg from the nestbox.Our results suggest that selection for retrieval behavior in this cavity-nesting host may be weak or even negative.We discuss several ecological and evolutionary factors that may explain the absence of retrieval in this system.展开更多
This study aims to mitigate crosswind-induced performance degradation in Natural Draft Dry Cooling Towers used in power plants by developing and assessing windbreak configurations that enhance ventilation while minimi...This study aims to mitigate crosswind-induced performance degradation in Natural Draft Dry Cooling Towers used in power plants by developing and assessing windbreak configurations that enhance ventilation while minimizing additional airflow resistance.Three novel windbreak designs,namely single-windbreak configuration with curved profile,double-windbreak configuration with curved profile,and double-windbreak configuration with inverted curved profile,are proposed accordingly and evaluated against conventional solutions.Three-dimensional numerical models of a 120 m high NDDCT equipped with these windbreaks,together with a conventional Y-shaped windbreak,are developed for systematic comparison.The results demonstrate that windbreak effectiveness strongly depends on crosswind intensity.At low crosswind speeds of 0-6 m/s,the Y-shaped windbreak provides the greatest enhancement,increasing the ventilation rate by 25.45%and the heat rejection rate by 21.37%at 6 m/s compared with the no-windbreak configuration.In contrast,under moderate to strong crosswinds of 6-18 m/s,the single-windbreak configuration with curved profile exhibits superior performance.At 18 m/s,it increases the ventilation rate by 148.88%and the heat rejection rate by 79.74%relative to the baseline case,outperforming the Y-shaped windbreak by 26.59%in ventilation rate and 17.01%in heat rejection capacity.Analysis of airflow structure,temperature fields,and velocity distributions confirms that the single-windbreak configuration with curved profile more effectively suppresses crosswind penetration and promotes stable upward airflow at higher wind speeds.Based on a comprehensive assessment of aerodynamic and thermal performance,the Y-shaped windbreak is recommended for regions where crosswind speeds remain below 6 m/s,whereas the single-windbreak configuration with curved profile is preferable for sites exposed to stronger crosswinds exceeding this threshold.展开更多
Nail changes following upper extremity transplantation(UET)cannot be overlooked as they possess diagnostic and prognostic relevance in allotransplantation of upper limbs.This comprehensive review explores nail and nai...Nail changes following upper extremity transplantation(UET)cannot be overlooked as they possess diagnostic and prognostic relevance in allotransplantation of upper limbs.This comprehensive review explores nail and nail bed related changes encountered in UET recipients in the literature.The differential diagnosis of nail abnormalities in UET includes a wide range of systemic,local and iatrogenic conditions other than immune responses to the allograft.It requires interdisciplinary evaluation by primary transplant surgeons,pathologists,dermatologists and immunologists.The possible underlying mechanisms of nail pathology in UET and the management are discussed.It also underscores the importance of onychodystrophy and need for timely intervention and to improve outcomes in UET recipients.展开更多
Post-kidney transplant rejection is a critical factor influencing transplant success rates and the survival of transplanted organs.With the rapid advancement of artificial intelligence technologies,machine learning(ML...Post-kidney transplant rejection is a critical factor influencing transplant success rates and the survival of transplanted organs.With the rapid advancement of artificial intelligence technologies,machine learning(ML)has emerged as a powerful data analysis tool,widely applied in the prediction,diagnosis,and mechanistic study of kidney transplant rejection.This mini-review systematically summarizes the recent applications of ML techniques in post-kidney transplant rejection,covering areas such as the construction of predictive models,identification of biomarkers,analysis of pathological images,assessment of immune cell infiltration,and formulation of personalized treatment strategies.By integrating multi-omics data and clinical information,ML has significantly enhanced the accuracy of early rejection diagnosis and the capability for prognostic evaluation,driving the development of precision medicine in the field of kidney transplantation.Furthermore,this article discusses the challenges faced in existing research and potential future directions,providing a theoretical basis and technical references for related studies.展开更多
Microelectromechanical systems(MEMS)technology has gained significant attention over the past decade for measuring inertial angular velocity.However,due to inherent complexity,MEMS gyroscopes typically feature up to t...Microelectromechanical systems(MEMS)technology has gained significant attention over the past decade for measuring inertial angular velocity.However,due to inherent complexity,MEMS gyroscopes typically feature up to ten times more parameters than traditional sensors,making selection a challenging task even for experts.This study addresses this challenge,focusing on defensive guidance,navigation,and control(GNC)systems where precise and reliable angular velocity measurement is critical to overall performance.A comprehensive mathematical model is introduced to encapsulate all key MEMS parameters,accompanied by discussions on calibration and Allan variance interpretation.For six leading MEMS gyroscope applications,namely inertial navigation,integrated navigation,autopilot systems,rotating projectiles,homing guidance,and north finding,the most critical parameters are identified,distinguishing suitable and unsuitable sensor choices.Special emphasis is placed on inertial navigation systems,where practical rules of thumb for error evaluation are derived using six degrees of freedom motion equations.Rigorous simulations demonstrate the influence of various sensor parameters through real-world case studies,including static navigation,multi-rotor attitude estimation,gimbal stabilization,and north finding via a turntable.This work aims to be a beacon for practitioners across diverse fields,empowering them to make more informed design decisions.展开更多
BACKGROUND Donor-specific antibodies(DSAs)against human leukocyte antigen(HLA)-DQ are increasingly recognized as major contributors to antibody-mediated rejection(AMR)and graft failure in kidney transplantation.Howeve...BACKGROUND Donor-specific antibodies(DSAs)against human leukocyte antigen(HLA)-DQ are increasingly recognized as major contributors to antibody-mediated rejection(AMR)and graft failure in kidney transplantation.However,their clinical impact remains understudied in Morocco.AIM To evaluate the presence and implications of anti-HLA-DQ DSAs in Moroccan kidney transplant recipients.METHODS We retrospectively analyzed the immunological profiles and clinical outcomes of kidney transplant recipients screened for anti-HLA antibodies between 2015 and 2020,who developed anti-HLA-DQ DSAs either before or after transplantation.Anti-HLA antibodies were identified using Luminex®single antigen bead technology,and clinical follow-up included graft function assessment,biopsy interpretation,and evaluation of immunosuppression.RESULTS In the pre-transplant group(n=6 with confirmed donor typing),patients with low to moderate median fluorescence intensity(MFI)anti-HLA-DQ DSAs(MFI 561-1581)underwent successful transplantation and maintained stable graft function under optimized immunosuppression.In contrast,in the post-transplant group(n=6 with confirmed donor typing),the emergence of de novo anti-HLA-DQ DSAs was consistently associated with AMR,with MFI values reaching up to 19473,with biopsy-proven AMR in 5 of 6 cases and suspicion of AMR in 1 case.Two representative cases are detailed to illustrate the clinical impact of DQ DSAs:one patient developed high-level anti-DQB1*02 de novo DSA(MFI 12029)with persistent AMR after 5 years,while another developed anti-DQA1*05:01 de novo DSA after an early AMR episode but maintained stable graft function after 5 years(creatinine 1.48 mg/dL).CONCLUSION Our findings underscore the clinical significance of anti-HLA-DQ DSAs in Moroccan kidney transplant recipients.While preformed DSAs with low immunogenicity may permit successful transplantation,de novo DSAs strongly correlate with AMR.Proactive monitoring,including routine DSA screening and HLA-DQ typing,could improve graft outcomes by enabling early intervention and better donor selection.展开更多
On April 27,BOCOG called a news conference where BOCOG Executive Vice President and Spokesperson Jiang Xiaoyu gave a statement regarding the Olympic torch passing through Taipei.BOCOG believes that the Chinese Taipei
The role of antibodies in kidney transplant(KT)has evolved significantly over the past few decades.This role of antibodies in KT is multifaceted,encompassing both the challenges they pose in terms of antibody-mediated...The role of antibodies in kidney transplant(KT)has evolved significantly over the past few decades.This role of antibodies in KT is multifaceted,encompassing both the challenges they pose in terms of antibody-mediated rejection(AMR)and the opportunities for improving transplant outcomes through better detection,prevention,and treatment strategies.As our understanding of the immunological mechanisms continues to evolve,so too will the approaches to managing and harnessing the power of antibodies in KT,ultimately leading to improved patient and graft survival.This narrative review explores the multifaceted roles of antibodies in KT,including their involvement in rejection mechanisms,advancements in desensitization protocols,AMR treatments,and their potential role in monitoring and improving graft survival.展开更多
Over the past six decades,liver transplantation(LT)has evolved from an experimental procedure into a standardized and life-saving intervention,reshaping the landscape of organ transplantation.Driven by pioneering brea...Over the past six decades,liver transplantation(LT)has evolved from an experimental procedure into a standardized and life-saving intervention,reshaping the landscape of organ transplantation.Driven by pioneering breakthroughs,technological advancements,and a deepened understanding of immunology,LT has seen remarkable progress.Some of the most notable breakthroughs in the field include advances in immunosuppression,a revised model for end-stage liver disease,and artificial intelligence(AI)-integrated imaging modalities serving diagnostic and therapeutic roles in LT,paired with ever-evolving technological advances.Additionally,the refinement of transplantation procedures,resulting in the introduction of alternative transplantation methods,such as living donor LT,split LT,and the use of marginal grafts,has addressed the challenge of organ shortage.Moreover,precision medicine,guiding personalized immunosuppressive strategies,has significantly improved patient and graft survival rates while addressing emergent issues,such as short-term complications and early allograft dysfunction,leading to a more refined strategy and enhanced postoperative recovery.Looking ahead,ongoing research explores regenerative medicine,diagnostic tools,and AI to optimize organ allocation and posttransplantation car.In summary,the past six decades have marked a transformative journey in LT with a commitment to advancing science,medicine,and patient-centered care,offering hope and extending life to individuals worldwide.展开更多
The main scientific payload of Macao Science Satellite-1B is a solar soft X-ray detection unit.To obtain an accurate solar X-ray spectrum,we have designed low-noise,high-throughput electronics.Solar radiation is detec...The main scientific payload of Macao Science Satellite-1B is a solar soft X-ray detection unit.To obtain an accurate solar X-ray spectrum,we have designed low-noise,high-throughput electronics.Solar radiation is detected using a low-leakage silicon drift detector(SDD),which is cooled to-30℃.The SDD output is processed using two parallel shaping amplifiers with peaking times of 315 ns and 65 ns.The amplifiers are designed using two-pole multiple-feedback active low-pass filters optimized to achieve a Bessel response.The differential output of the shaping amplifier generates a bipolar signal.The phase of the differential stage is tuned to ensure zero crossing corresponding to the peak of the shaping amplifier.A high-speed switch is inserted between the shaping amplifier and the peak-hold capacitor,and the peak value is maintained by turning off the switch.Fast and slow peak-hold circuits share a common ADC via time-division multiplexing.Both peak values are sampled for space-background rejection.Traditional pile-up detection methods cannot distinguish pulses that overlap in a fast channel.In this study,the differential of the“fast shaping”is selected,enabling the distinction of events separated by as little as 65ns,which is crucial for solar flare detection.The energy resolution is measured to be 138 eV at 5.90 keV.The centroid drift is less than 3.6 eV between-5℃ and 20℃.Compared with other solar X-ray instruments,this study demonstrates improved energy resolution with a lower peaking time,indicating a higher solar flare detection capability.展开更多
The output feedback active disturbance rejection control of a valve-controlled cylinder electro-hydraulic servo system is investigated in this paper.First,a comprehensive nonlinear mathematical model that encompasses ...The output feedback active disturbance rejection control of a valve-controlled cylinder electro-hydraulic servo system is investigated in this paper.First,a comprehensive nonlinear mathematical model that encompasses both matched and mismatched disturbances is formulated.Due to the fact that only position information can be measured,a linear Extended State Observer(ESO)is introduced to estimate unknown states and matched disturbances,while a dedicated disturbance observer is constructed to estimate mismatched disturbances.Different from the traditional observer results,the design of the disturbance observer used in this study is carried out under the constraint of output feedback.Furthermore,an output feedback nonlinear controller is proposed leveraging the aforementioned observers to achieve accurate trajectory tracking.To mitigate the inherent differential explosion problem of the traditional backstepping framework,a finite-time stable command filter is incorporated.Simultaneously,considering transient filtering errors,a set of error compensation signals are designed to counter their negative impact effectively.Theoretical analysis affirms that the proposed control strategy ensures the boundedness of all signals within the closed-loop system.Additionally,under the specific condition of only time-invariant disturbances in the system,the conclusion of asymptotic stability is established.Finally,the algorithm’s efficacy is validated through comparative experiments.展开更多
Permanent magnet synchronous motor based electro-mechanical actuation servo drives have widespread applications in the aviation field,such as unmanned aerial vehicle electric servos,electric cabin doors,and mechanical...Permanent magnet synchronous motor based electro-mechanical actuation servo drives have widespread applications in the aviation field,such as unmanned aerial vehicle electric servos,electric cabin doors,and mechanical arms.The performance of the servo drive,which encompasses the response to the torque,efficiency,control bandwidth and the steady-state positioning accuracy,significantly influences the performance of the aviation actuation.Consequently,enhancing the control bandwidth and refining the positioning accuracy of aviation electro-mechanical actuation servo drives have emerged as a focal point of research.This paper investigates the multi-source disturbances present in aviation electro-mechanical actuation servo systems and summarizes recent research on high-performance servo control methods based on active disturbance rejection control(ADRC).We present a comprehensive overview of the research status pertaining to servo control architecture,strategies for suppressing disturbances in the current loop,and ADRC-based strategies for the position loop.We delineate the research challenges and difficulties encountered by aviation electro-mechanical actuation servo drive control technology.展开更多
Behavioral recovery using(viable)peripheral nerve allografts to repair ablation-type(segmental-loss)peripheral nerve injuries is delayed or poor due to slow and inaccurate axonal regeneration.Furthermore,such peripher...Behavioral recovery using(viable)peripheral nerve allografts to repair ablation-type(segmental-loss)peripheral nerve injuries is delayed or poor due to slow and inaccurate axonal regeneration.Furthermore,such peripheral nerve allografts undergo immunological rejection by the host immune system.In contrast,peripheral nerve injuries repaired by polyethylene glycol fusion of peripheral nerve allografts exhibit excellent behavioral recovery within weeks,reduced immune responses,and many axons do not undergo Wallerian degeneration.The relative contribution of neurorrhaphy and polyethylene glycol-fusion of axons versus the effects of polyethylene glycol per se was unknown prior to this study.We hypothesized that polyethylene glycol might have some immune-protective effects,but polyethylene glycol-fusion was necessary to prevent Wallerian degeneration and functional/behavioral recovery.We examined how polyethylene glycol solutions per se affect functional and behavioral recovery and peripheral nerve allograft morphological and immunological responses in the absence of polyethylene glycol-induced axonal fusion.Ablation-type sciatic nerve injuries in outbred Sprague–Dawley rats were repaired according to a modified protocol using the same solutions as polyethylene glycol-fused peripheral nerve allografts,but peripheral nerve allografts were loose-sutured(loose-sutured polyethylene glycol)with an intentional gap of 1–2 mm to prevent fusion by polyethylene glycol of peripheral nerve allograft axons with host axons.Similar to negative control peripheral nerve allografts not treated by polyethylene glycol and in contrast to polyethylene glycol-fused peripheral nerve allografts,animals with loose-sutured polyethylene glycol peripheral nerve allografts exhibited Wallerian degeneration for all axons and myelin degeneration by 7 days postoperatively and did not recover sciatic-mediated behavioral functions by 42 days postoperatively.Other morphological signs of rejection,such as collapsed Schwann cell basal lamina tubes,were absent in polyethylene glycol-fused peripheral nerve allografts but commonly observed in negative control and loose-sutured polyethylene glycol peripheral nerve allografts at 21 days postoperatively.Loose-sutured polyethylene glycol peripheral nerve allografts had more pro-inflammatory and less anti-inflammatory macrophages than negative control peripheral nerve allografts.While T cell counts were similarly high in loose-sutured-polyethylene glycol and negative control peripheral nerve allografts,loose-sutured polyethylene glycol peripheral nerve allografts expressed some cytokines/chemokines important for T cell activation at much lower levels at 14 days postoperatively.MHCI expression was elevated in loose-sutured polyethylene glycol peripheral nerve allografts,but MHCII expression was modestly lower compared to negative control at 21 days postoperatively.We conclude that,while polyethylene glycol per se reduces some immune responses of peripheral nerve allografts,successful polyethylene glycol-fusion repair of some axons is necessary to prevent Wallerian degeneration of those axons and immune rejection of peripheral nerve allografts,and produce recovery of sensory/motor functions and voluntary behaviors.Translation of polyethylene glycol-fusion technologies would produce a paradigm shift from the current clinical practice of waiting days to months to repair ablation peripheral nerve injuries.展开更多
In this article,we comment on an article published in a recent issue of the World Journal of Gastroenterology.We specifically focus on the roles of human leukocyte antigen(HLA)and donor-specific antibodies(DSAs)in ped...In this article,we comment on an article published in a recent issue of the World Journal of Gastroenterology.We specifically focus on the roles of human leukocyte antigen(HLA)and donor-specific antibodies(DSAs)in pediatric liver transpl-antation(LT),as well as the relationship between immune rejection after LT and DSA.Currently,LT remains the standard of care for pediatric patients with end-stage liver disease or severe acute liver failure.However,acute and chronic re-jection continues to be a significant cause of graft dysfunction and loss.HLA mismatch significantly reduces graft survival and increases the risk of acute rejection.Among them,D→R one-way mismatch at three loci was significantly related to graft-versus-host disease incidence after LT.The adverse impact of HLA-DSAs on LT recipients is already established.Therefore,the evaluation of HLA and DSA is crucial in pediatric LT.展开更多
In recent years, the use of new biomarkers in different phases of the diagnosis andtreatment of several diseases has allowed substantial improvement in clinicalpractice. The use of donor-derived cell-free DNA (dd-cfDN...In recent years, the use of new biomarkers in different phases of the diagnosis andtreatment of several diseases has allowed substantial improvement in clinicalpractice. The use of donor-derived cell-free DNA (dd-cfDNA) in organ transplantationhas led to significant progress in the treatment of post-transplantoutcomes, particularly after kidney transplantation. In addition, the use of ddcfDNAin organ transplantation has led to significant advancements in posttransplantoutcome monitoring. The aim of this study is to review many of therecent studies on the use of this biomarker and to evaluate its most relevantadvantages and limitations. dd-cfDNA is released from several types of cells ofthe transplanted organ, most often from endothelial cells and this happens in thecase of organ damage, most often rejection. Its presence in the bloodstream of therecipients is an important sign of graft damage;its principal advantage is in theavoidance of invasive tools such as renal biopsy. Additionally, several studiesreported that the finding of dd-cfDNA in the serum may precede histologicalabnormalities;its utility in the diagnosis of subclinical rejection is extremelyimportant. Among the principal limitations of this tool are the difficulty in distinguishingdifferent forms of graft damage. According to several studies this toolhas several limitations in diagnosing T-cell mediated rejection. In addition,particular care should be taken in distinguishing dd-cfDNA from recipientderivedcfDNA.展开更多
1 Active Disturbance Rejection Control(ADRC):a brief survey Since its inception,Active Disturbance Rejection Control(ADRC)has re-centered feedback controller design around two fundamental ideas—along with a consequen...1 Active Disturbance Rejection Control(ADRC):a brief survey Since its inception,Active Disturbance Rejection Control(ADRC)has re-centered feedback controller design around two fundamental ideas—along with a consequential design simplification:real-time estimation and online cancellation of the“total disturbance”conceived as the lumped effect of unknown internal dynamics and external inputs.The simplified design then proceeds in a customary fashion for the ideally remaining system model,which is devoid of the total disturbance.展开更多
Antibody-mediated rejection(AMR)represents a major challenge in kidney transplantation,significantly contributing to tissue injury and graft failure.AMR is primarily driven by donor-specific alloantibodies(DSAs),which...Antibody-mediated rejection(AMR)represents a major challenge in kidney transplantation,significantly contributing to tissue injury and graft failure.AMR is primarily driven by donor-specific alloantibodies(DSAs),which recognize and bind to specific target antigens present within the transplanted kidney tissue.Upon binding,these DSAs commonly initiate activation of the complement system within the graft.The activation of the complement cascade sets off a powerful inflammatory response characterized by the recruitment and activation of immune cells,endothelial damage,and subsequent tissue injury.This inflammation underlies many clinical and histological manifestations of AMR,making complement activation a critical player in the disease process.Advancements in our understanding of how complement pathways contribute to kidney graft injury have opened new avenues for therapeutic intervention.Recent research has facilitated the development and application of novel therapies specifically designed to inhibit complement activation.Such targeted complement-inhibitory strategies have shown promise in improving graft outcomes by inhibiting complement-mediated damage and extending graft survival.This review comprehensively discusses the critical role of complement activation in inducing kidney graft injury with a focus on its role in AMR.By elucidating the detailed mechanisms and contributions of complement pathways,the review seeks to enhance the understanding necessary for developing targeted therapeutic interventions to prevent or treat AMR effectively.展开更多
文摘This study investigates prescribed-time position tracking control for electromagnetic satellite formations subject to model uncertainties and external disturbances.Using the Clohessy-Wiltshire equations as the relative motion dynamics model,a prescribed time output feedback control strategy is proposed.A prescribed-time extended state observer is designed to estimate the relative velocity and external disturbances.The disturbance estimates are then used as the feedforward component of the controller.Building on this framework,a novel prescribed-time active disturbance rejection control strategy for position tracking is developed via a backstepping control design.The convergence of the extended state observer and the stability of the closed-loop system are rigorously analyzed using Lyapunov stability theory.Numerical simulations are performed to validate the effectiveness of the proposed controller.
基金supported by the National Natural Science Foundation of China(No.62371263)the Postgraduate Research&Practice Innovation Program of Jiangsu Province(No.SJCK25_1995).
文摘1 Introduction Recently,the increasing demand for advanced telecommunication systems has spurred extensive research into bandpass filters(BPFs),with particular emphasis on miniaturization,reduction of insertion loss(IL),and enhancement of upper stopband rejection(Huang et al.,2021;Snyder et al.,2021;Lin et al.,2023;Zeng et al.,2023).
文摘Antibody-mediated rejection(AMR)remains a leading cause of kidney allograft failure,posing significant clinical and economic challenges.Donor-specific antibodies against human leukocyte antigens or non-human leukocyte antigens are critical risk factors for AMR and graft loss.The diagnostic criteria and classification of AMR have evolved considerably over the past three decades,driven largely by the Banff classification.The latest Banff 2022 classification introduced two additional subcategories of“microvascular inflammation,donor-specific antibody-negative,C4d-negative”and“probable AMR”.Traditionally,graft monitoring has relied on non-specific markers such as serum creatinine and proteinuria,and the invasive biopsies.Noninvasive tools using blood and urine biomarkers,including cellular assays and molecular profiling,are increasingly being investigated.Technologies such as the Molecular Microscope Diagnostic System show promise,with studies reporting 80%sensitivity and 90%specificity in detecting AMR.Treatment of AMR remains inconsistent.Recent advances,including CD38 antibodies,have demonstrated up to 60%efficacy in reversing AMR,while complement inhibition shows potential in severe early cases.Ongoing clinical trials evaluating high-dose intravenous immunoglobulin,efgartigimod,fostamatinib,and other novel therapies aim to expand treatment options.These developments highlight the need for well-designed clinical trials to validate biomarkers and therapies and to improve long-term outcomes for kidney transplant recipients.
基金supported by the startup fund from Beijing Normal University(312200502560 to J.Z.)the National Natural Science Foundation of China(32501383 to J.Z.,and 31672297 and 32271559 to W.D.)the Max Planck Society(to B.K.)。
文摘The arms race between avian brood parasites and their hosts provides a classic model for studying coevolution.In one of the most widespread obligate brood parasites,the Common Cuckoo(Cuculus canorus),chicks typically evict all host progeny(eggs and nestlings)from the nest cup,resulting in complete reproductive failure for the host.Host parents of Common Cuckoos could thus potentially benefit from retrieving evicted eggs and nestlings into the nest cup.However,whether hosts of the Common Cuckoo exhibit such retrieval behavior has been scarcely studied.In this study,we experimentally investigated the occurrence of retrieval in a nestbox-breeding population of Daurian Redstarts(Phoenicurus auroreus),a common cavity-nesting host of the Common Cuckoo.To test the redstarts'response to an egg or a nestling outside the nest cup,we experimentally placed either a conspecific egg,a model cuckoo egg,or a redstart nestling near the rim of the nest cup.We found that redstarts never showed retrieval behavior of either eggs or nestlings.All hosts ignored the experimental nestling and conspecific egg,but most ejected the model cuckoo egg from the nestbox.Our results suggest that selection for retrieval behavior in this cavity-nesting host may be weak or even negative.We discuss several ecological and evolutionary factors that may explain the absence of retrieval in this system.
基金supported by the National Natural Science Foundation of China(Grant No.52476206)the Key R&D Program of Shandong Province,China(Grant No.2025CXGC010203)+1 种基金the Guangdong Basic and Applied Basic Research Foundation(Grant No.2025A1515012123)the Shandong Natural Science Foundation(Grant No.ZR2022ME008).
文摘This study aims to mitigate crosswind-induced performance degradation in Natural Draft Dry Cooling Towers used in power plants by developing and assessing windbreak configurations that enhance ventilation while minimizing additional airflow resistance.Three novel windbreak designs,namely single-windbreak configuration with curved profile,double-windbreak configuration with curved profile,and double-windbreak configuration with inverted curved profile,are proposed accordingly and evaluated against conventional solutions.Three-dimensional numerical models of a 120 m high NDDCT equipped with these windbreaks,together with a conventional Y-shaped windbreak,are developed for systematic comparison.The results demonstrate that windbreak effectiveness strongly depends on crosswind intensity.At low crosswind speeds of 0-6 m/s,the Y-shaped windbreak provides the greatest enhancement,increasing the ventilation rate by 25.45%and the heat rejection rate by 21.37%at 6 m/s compared with the no-windbreak configuration.In contrast,under moderate to strong crosswinds of 6-18 m/s,the single-windbreak configuration with curved profile exhibits superior performance.At 18 m/s,it increases the ventilation rate by 148.88%and the heat rejection rate by 79.74%relative to the baseline case,outperforming the Y-shaped windbreak by 26.59%in ventilation rate and 17.01%in heat rejection capacity.Analysis of airflow structure,temperature fields,and velocity distributions confirms that the single-windbreak configuration with curved profile more effectively suppresses crosswind penetration and promotes stable upward airflow at higher wind speeds.Based on a comprehensive assessment of aerodynamic and thermal performance,the Y-shaped windbreak is recommended for regions where crosswind speeds remain below 6 m/s,whereas the single-windbreak configuration with curved profile is preferable for sites exposed to stronger crosswinds exceeding this threshold.
文摘Nail changes following upper extremity transplantation(UET)cannot be overlooked as they possess diagnostic and prognostic relevance in allotransplantation of upper limbs.This comprehensive review explores nail and nail bed related changes encountered in UET recipients in the literature.The differential diagnosis of nail abnormalities in UET includes a wide range of systemic,local and iatrogenic conditions other than immune responses to the allograft.It requires interdisciplinary evaluation by primary transplant surgeons,pathologists,dermatologists and immunologists.The possible underlying mechanisms of nail pathology in UET and the management are discussed.It also underscores the importance of onychodystrophy and need for timely intervention and to improve outcomes in UET recipients.
文摘Post-kidney transplant rejection is a critical factor influencing transplant success rates and the survival of transplanted organs.With the rapid advancement of artificial intelligence technologies,machine learning(ML)has emerged as a powerful data analysis tool,widely applied in the prediction,diagnosis,and mechanistic study of kidney transplant rejection.This mini-review systematically summarizes the recent applications of ML techniques in post-kidney transplant rejection,covering areas such as the construction of predictive models,identification of biomarkers,analysis of pathological images,assessment of immune cell infiltration,and formulation of personalized treatment strategies.By integrating multi-omics data and clinical information,ML has significantly enhanced the accuracy of early rejection diagnosis and the capability for prognostic evaluation,driving the development of precision medicine in the field of kidney transplantation.Furthermore,this article discusses the challenges faced in existing research and potential future directions,providing a theoretical basis and technical references for related studies.
文摘Microelectromechanical systems(MEMS)technology has gained significant attention over the past decade for measuring inertial angular velocity.However,due to inherent complexity,MEMS gyroscopes typically feature up to ten times more parameters than traditional sensors,making selection a challenging task even for experts.This study addresses this challenge,focusing on defensive guidance,navigation,and control(GNC)systems where precise and reliable angular velocity measurement is critical to overall performance.A comprehensive mathematical model is introduced to encapsulate all key MEMS parameters,accompanied by discussions on calibration and Allan variance interpretation.For six leading MEMS gyroscope applications,namely inertial navigation,integrated navigation,autopilot systems,rotating projectiles,homing guidance,and north finding,the most critical parameters are identified,distinguishing suitable and unsuitable sensor choices.Special emphasis is placed on inertial navigation systems,where practical rules of thumb for error evaluation are derived using six degrees of freedom motion equations.Rigorous simulations demonstrate the influence of various sensor parameters through real-world case studies,including static navigation,multi-rotor attitude estimation,gimbal stabilization,and north finding via a turntable.This work aims to be a beacon for practitioners across diverse fields,empowering them to make more informed design decisions.
基金Supported by the National Science and Technology Research Center(Morocco)“PhD-Associate Scholarship-PASS”Program,No.88UH2C2023.
文摘BACKGROUND Donor-specific antibodies(DSAs)against human leukocyte antigen(HLA)-DQ are increasingly recognized as major contributors to antibody-mediated rejection(AMR)and graft failure in kidney transplantation.However,their clinical impact remains understudied in Morocco.AIM To evaluate the presence and implications of anti-HLA-DQ DSAs in Moroccan kidney transplant recipients.METHODS We retrospectively analyzed the immunological profiles and clinical outcomes of kidney transplant recipients screened for anti-HLA antibodies between 2015 and 2020,who developed anti-HLA-DQ DSAs either before or after transplantation.Anti-HLA antibodies were identified using Luminex®single antigen bead technology,and clinical follow-up included graft function assessment,biopsy interpretation,and evaluation of immunosuppression.RESULTS In the pre-transplant group(n=6 with confirmed donor typing),patients with low to moderate median fluorescence intensity(MFI)anti-HLA-DQ DSAs(MFI 561-1581)underwent successful transplantation and maintained stable graft function under optimized immunosuppression.In contrast,in the post-transplant group(n=6 with confirmed donor typing),the emergence of de novo anti-HLA-DQ DSAs was consistently associated with AMR,with MFI values reaching up to 19473,with biopsy-proven AMR in 5 of 6 cases and suspicion of AMR in 1 case.Two representative cases are detailed to illustrate the clinical impact of DQ DSAs:one patient developed high-level anti-DQB1*02 de novo DSA(MFI 12029)with persistent AMR after 5 years,while another developed anti-DQA1*05:01 de novo DSA after an early AMR episode but maintained stable graft function after 5 years(creatinine 1.48 mg/dL).CONCLUSION Our findings underscore the clinical significance of anti-HLA-DQ DSAs in Moroccan kidney transplant recipients.While preformed DSAs with low immunogenicity may permit successful transplantation,de novo DSAs strongly correlate with AMR.Proactive monitoring,including routine DSA screening and HLA-DQ typing,could improve graft outcomes by enabling early intervention and better donor selection.
文摘On April 27,BOCOG called a news conference where BOCOG Executive Vice President and Spokesperson Jiang Xiaoyu gave a statement regarding the Olympic torch passing through Taipei.BOCOG believes that the Chinese Taipei
文摘The role of antibodies in kidney transplant(KT)has evolved significantly over the past few decades.This role of antibodies in KT is multifaceted,encompassing both the challenges they pose in terms of antibody-mediated rejection(AMR)and the opportunities for improving transplant outcomes through better detection,prevention,and treatment strategies.As our understanding of the immunological mechanisms continues to evolve,so too will the approaches to managing and harnessing the power of antibodies in KT,ultimately leading to improved patient and graft survival.This narrative review explores the multifaceted roles of antibodies in KT,including their involvement in rejection mechanisms,advancements in desensitization protocols,AMR treatments,and their potential role in monitoring and improving graft survival.
文摘Over the past six decades,liver transplantation(LT)has evolved from an experimental procedure into a standardized and life-saving intervention,reshaping the landscape of organ transplantation.Driven by pioneering breakthroughs,technological advancements,and a deepened understanding of immunology,LT has seen remarkable progress.Some of the most notable breakthroughs in the field include advances in immunosuppression,a revised model for end-stage liver disease,and artificial intelligence(AI)-integrated imaging modalities serving diagnostic and therapeutic roles in LT,paired with ever-evolving technological advances.Additionally,the refinement of transplantation procedures,resulting in the introduction of alternative transplantation methods,such as living donor LT,split LT,and the use of marginal grafts,has addressed the challenge of organ shortage.Moreover,precision medicine,guiding personalized immunosuppressive strategies,has significantly improved patient and graft survival rates while addressing emergent issues,such as short-term complications and early allograft dysfunction,leading to a more refined strategy and enhanced postoperative recovery.Looking ahead,ongoing research explores regenerative medicine,diagnostic tools,and AI to optimize organ allocation and posttransplantation car.In summary,the past six decades have marked a transformative journey in LT with a commitment to advancing science,medicine,and patient-centered care,offering hope and extending life to individuals worldwide.
基金supported by the National Natural Science Foundation of China(No.12035020)National Key Scientific Instrument and Equipment Development Projects of China(No.42327802).
文摘The main scientific payload of Macao Science Satellite-1B is a solar soft X-ray detection unit.To obtain an accurate solar X-ray spectrum,we have designed low-noise,high-throughput electronics.Solar radiation is detected using a low-leakage silicon drift detector(SDD),which is cooled to-30℃.The SDD output is processed using two parallel shaping amplifiers with peaking times of 315 ns and 65 ns.The amplifiers are designed using two-pole multiple-feedback active low-pass filters optimized to achieve a Bessel response.The differential output of the shaping amplifier generates a bipolar signal.The phase of the differential stage is tuned to ensure zero crossing corresponding to the peak of the shaping amplifier.A high-speed switch is inserted between the shaping amplifier and the peak-hold capacitor,and the peak value is maintained by turning off the switch.Fast and slow peak-hold circuits share a common ADC via time-division multiplexing.Both peak values are sampled for space-background rejection.Traditional pile-up detection methods cannot distinguish pulses that overlap in a fast channel.In this study,the differential of the“fast shaping”is selected,enabling the distinction of events separated by as little as 65ns,which is crucial for solar flare detection.The energy resolution is measured to be 138 eV at 5.90 keV.The centroid drift is less than 3.6 eV between-5℃ and 20℃.Compared with other solar X-ray instruments,this study demonstrates improved energy resolution with a lower peaking time,indicating a higher solar flare detection capability.
基金supported by the National Key R&D Program of China(No.2021YFB2011300)the Special Funds Project for the Transformation of Scientific and Technological Achievements of Jiangsu Province,China(No.BA2023039)+1 种基金the National Natural Science Foundation of China(No.52075262)the Fundamental Research Funds for the Central Universities,China(No.30922010706).
文摘The output feedback active disturbance rejection control of a valve-controlled cylinder electro-hydraulic servo system is investigated in this paper.First,a comprehensive nonlinear mathematical model that encompasses both matched and mismatched disturbances is formulated.Due to the fact that only position information can be measured,a linear Extended State Observer(ESO)is introduced to estimate unknown states and matched disturbances,while a dedicated disturbance observer is constructed to estimate mismatched disturbances.Different from the traditional observer results,the design of the disturbance observer used in this study is carried out under the constraint of output feedback.Furthermore,an output feedback nonlinear controller is proposed leveraging the aforementioned observers to achieve accurate trajectory tracking.To mitigate the inherent differential explosion problem of the traditional backstepping framework,a finite-time stable command filter is incorporated.Simultaneously,considering transient filtering errors,a set of error compensation signals are designed to counter their negative impact effectively.Theoretical analysis affirms that the proposed control strategy ensures the boundedness of all signals within the closed-loop system.Additionally,under the specific condition of only time-invariant disturbances in the system,the conclusion of asymptotic stability is established.Finally,the algorithm’s efficacy is validated through comparative experiments.
基金supported by the National Natural Science Foundation of China(Nos.52177059 and 52407064).
文摘Permanent magnet synchronous motor based electro-mechanical actuation servo drives have widespread applications in the aviation field,such as unmanned aerial vehicle electric servos,electric cabin doors,and mechanical arms.The performance of the servo drive,which encompasses the response to the torque,efficiency,control bandwidth and the steady-state positioning accuracy,significantly influences the performance of the aviation actuation.Consequently,enhancing the control bandwidth and refining the positioning accuracy of aviation electro-mechanical actuation servo drives have emerged as a focal point of research.This paper investigates the multi-source disturbances present in aviation electro-mechanical actuation servo systems and summarizes recent research on high-performance servo control methods based on active disturbance rejection control(ADRC).We present a comprehensive overview of the research status pertaining to servo control architecture,strategies for suppressing disturbances in the current loop,and ADRC-based strategies for the position loop.We delineate the research challenges and difficulties encountered by aviation electro-mechanical actuation servo drive control technology.
基金supported by grants from the Lone Star Paralysis Foundation,NIH R01NS081063Department of Defense award W81XWH-19-2-0054 to GDB+2 种基金supported by University of Wyoming Startup funds,Department of Defense grant W81XWH-17-1-0402the University of Wyoming Sensory Biology COBRE under National Institutes of Health(NIH)award number 5P20GM121310-02the National Institute of General Medical Sciences of the NIH under award number P20GM103432 to JSB。
文摘Behavioral recovery using(viable)peripheral nerve allografts to repair ablation-type(segmental-loss)peripheral nerve injuries is delayed or poor due to slow and inaccurate axonal regeneration.Furthermore,such peripheral nerve allografts undergo immunological rejection by the host immune system.In contrast,peripheral nerve injuries repaired by polyethylene glycol fusion of peripheral nerve allografts exhibit excellent behavioral recovery within weeks,reduced immune responses,and many axons do not undergo Wallerian degeneration.The relative contribution of neurorrhaphy and polyethylene glycol-fusion of axons versus the effects of polyethylene glycol per se was unknown prior to this study.We hypothesized that polyethylene glycol might have some immune-protective effects,but polyethylene glycol-fusion was necessary to prevent Wallerian degeneration and functional/behavioral recovery.We examined how polyethylene glycol solutions per se affect functional and behavioral recovery and peripheral nerve allograft morphological and immunological responses in the absence of polyethylene glycol-induced axonal fusion.Ablation-type sciatic nerve injuries in outbred Sprague–Dawley rats were repaired according to a modified protocol using the same solutions as polyethylene glycol-fused peripheral nerve allografts,but peripheral nerve allografts were loose-sutured(loose-sutured polyethylene glycol)with an intentional gap of 1–2 mm to prevent fusion by polyethylene glycol of peripheral nerve allograft axons with host axons.Similar to negative control peripheral nerve allografts not treated by polyethylene glycol and in contrast to polyethylene glycol-fused peripheral nerve allografts,animals with loose-sutured polyethylene glycol peripheral nerve allografts exhibited Wallerian degeneration for all axons and myelin degeneration by 7 days postoperatively and did not recover sciatic-mediated behavioral functions by 42 days postoperatively.Other morphological signs of rejection,such as collapsed Schwann cell basal lamina tubes,were absent in polyethylene glycol-fused peripheral nerve allografts but commonly observed in negative control and loose-sutured polyethylene glycol peripheral nerve allografts at 21 days postoperatively.Loose-sutured polyethylene glycol peripheral nerve allografts had more pro-inflammatory and less anti-inflammatory macrophages than negative control peripheral nerve allografts.While T cell counts were similarly high in loose-sutured-polyethylene glycol and negative control peripheral nerve allografts,loose-sutured polyethylene glycol peripheral nerve allografts expressed some cytokines/chemokines important for T cell activation at much lower levels at 14 days postoperatively.MHCI expression was elevated in loose-sutured polyethylene glycol peripheral nerve allografts,but MHCII expression was modestly lower compared to negative control at 21 days postoperatively.We conclude that,while polyethylene glycol per se reduces some immune responses of peripheral nerve allografts,successful polyethylene glycol-fusion repair of some axons is necessary to prevent Wallerian degeneration of those axons and immune rejection of peripheral nerve allografts,and produce recovery of sensory/motor functions and voluntary behaviors.Translation of polyethylene glycol-fusion technologies would produce a paradigm shift from the current clinical practice of waiting days to months to repair ablation peripheral nerve injuries.
文摘In this article,we comment on an article published in a recent issue of the World Journal of Gastroenterology.We specifically focus on the roles of human leukocyte antigen(HLA)and donor-specific antibodies(DSAs)in pediatric liver transpl-antation(LT),as well as the relationship between immune rejection after LT and DSA.Currently,LT remains the standard of care for pediatric patients with end-stage liver disease or severe acute liver failure.However,acute and chronic re-jection continues to be a significant cause of graft dysfunction and loss.HLA mismatch significantly reduces graft survival and increases the risk of acute rejection.Among them,D→R one-way mismatch at three loci was significantly related to graft-versus-host disease incidence after LT.The adverse impact of HLA-DSAs on LT recipients is already established.Therefore,the evaluation of HLA and DSA is crucial in pediatric LT.
文摘In recent years, the use of new biomarkers in different phases of the diagnosis andtreatment of several diseases has allowed substantial improvement in clinicalpractice. The use of donor-derived cell-free DNA (dd-cfDNA) in organ transplantationhas led to significant progress in the treatment of post-transplantoutcomes, particularly after kidney transplantation. In addition, the use of ddcfDNAin organ transplantation has led to significant advancements in posttransplantoutcome monitoring. The aim of this study is to review many of therecent studies on the use of this biomarker and to evaluate its most relevantadvantages and limitations. dd-cfDNA is released from several types of cells ofthe transplanted organ, most often from endothelial cells and this happens in thecase of organ damage, most often rejection. Its presence in the bloodstream of therecipients is an important sign of graft damage;its principal advantage is in theavoidance of invasive tools such as renal biopsy. Additionally, several studiesreported that the finding of dd-cfDNA in the serum may precede histologicalabnormalities;its utility in the diagnosis of subclinical rejection is extremelyimportant. Among the principal limitations of this tool are the difficulty in distinguishingdifferent forms of graft damage. According to several studies this toolhas several limitations in diagnosing T-cell mediated rejection. In addition,particular care should be taken in distinguishing dd-cfDNA from recipientderivedcfDNA.
文摘1 Active Disturbance Rejection Control(ADRC):a brief survey Since its inception,Active Disturbance Rejection Control(ADRC)has re-centered feedback controller design around two fundamental ideas—along with a consequential design simplification:real-time estimation and online cancellation of the“total disturbance”conceived as the lumped effect of unknown internal dynamics and external inputs.The simplified design then proceeds in a customary fashion for the ideally remaining system model,which is devoid of the total disturbance.
文摘Antibody-mediated rejection(AMR)represents a major challenge in kidney transplantation,significantly contributing to tissue injury and graft failure.AMR is primarily driven by donor-specific alloantibodies(DSAs),which recognize and bind to specific target antigens present within the transplanted kidney tissue.Upon binding,these DSAs commonly initiate activation of the complement system within the graft.The activation of the complement cascade sets off a powerful inflammatory response characterized by the recruitment and activation of immune cells,endothelial damage,and subsequent tissue injury.This inflammation underlies many clinical and histological manifestations of AMR,making complement activation a critical player in the disease process.Advancements in our understanding of how complement pathways contribute to kidney graft injury have opened new avenues for therapeutic intervention.Recent research has facilitated the development and application of novel therapies specifically designed to inhibit complement activation.Such targeted complement-inhibitory strategies have shown promise in improving graft outcomes by inhibiting complement-mediated damage and extending graft survival.This review comprehensively discusses the critical role of complement activation in inducing kidney graft injury with a focus on its role in AMR.By elucidating the detailed mechanisms and contributions of complement pathways,the review seeks to enhance the understanding necessary for developing targeted therapeutic interventions to prevent or treat AMR effectively.
