The performance of Nb superconducting quantum devices is predominantly limited by dielectric loss at the metal–air interface,where Nb2O5 is considered the main loss source.Here,we suppress the formation of native oxi...The performance of Nb superconducting quantum devices is predominantly limited by dielectric loss at the metal–air interface,where Nb2O5 is considered the main loss source.Here,we suppress the formation of native oxides by in-situ deposition of a TiN capping layer on the Nb film.With TiN capping layers,no Nb2O5 forms on the surface of the Nb film.The quality factor Qi of the Nb resonator increases from 5.6×10^(5) to 7.9×10^(5) at low input power and from 6.8×10^(6) to 1.1×10^(7)at high input power.Furthermore,the TiN capping layer also shows good aging resistance in Nb resonator devices,with no significant performance fluctuations after one month of aging.These findings highlight the effectiveness of TiN capping layers in enhancing the performance and longevity of Nb superconducting quantum devices.展开更多
Reducing the control error is vital for high-fidelity digital and analog quantum operations.In superconducting circuits,one disagreeable error arises from the reflection of microwave signals due to impedance mismatch ...Reducing the control error is vital for high-fidelity digital and analog quantum operations.In superconducting circuits,one disagreeable error arises from the reflection of microwave signals due to impedance mismatch in the control chain.Here,we demonstrate a reflection cancelation method when considering that there are two reflection nodes on the control line.We propose to generate the pre-distortion pulse by passing the envelopes of the microwave signal through digital filters,which enables real-time reflection correction when integrated into the field-programmable gate array(FPGA).We achieve a reduction of single-qubit gate infidelity from 0.67%to 0.11%after eliminating microwave reflection.Real-time correction of microwave reflection paves the way for precise control and manipulation of the qubit state and would ultimately enhance the performance of algorithms and simulations executed on quantum processors.展开更多
Effective path planning is crucial for mobile robots to quickly reach rescue destination and complete rescue tasks in a post-disaster scenario.In this study,we investigated the post-disaster rescue path planning probl...Effective path planning is crucial for mobile robots to quickly reach rescue destination and complete rescue tasks in a post-disaster scenario.In this study,we investigated the post-disaster rescue path planning problem and modeled this problem as a variant of the travel salesman problem(TSP)with life-strength constraints.To address this problem,we proposed an improved iterated greedy(IIG)algorithm.First,a push-forward insertion heuristic(PFIH)strategy was employed to generate a high-quality initial solution.Second,a greedy-based insertion strategy was designed and used in the destruction-construction stage to increase the algorithm’s exploration ability.Furthermore,three problem-specific swap operators were developed to improve the algorithm’s exploitation ability.Additionally,an improved simulated annealing(SA)strategy was used as an acceptance criterion to effectively prevent the algorithm from falling into local optima.To verify the effectiveness of the proposed algorithm,the Solomon dataset was extended to generate 27 instances for simulation.Finally,the proposed IIG was compared with five state-of-the-art algorithms.The parameter analysiswas conducted using the design of experiments(DOE)Taguchi method,and the effectiveness analysis of each component has been verified one by one.Simulation results indicate that IIGoutperforms the compared algorithms in terms of the number of rescue survivors and convergence speed,proving the effectiveness of the proposed algorithm.展开更多
Background: Delayed gastric emptying(DGE) is one of the most common complications after pancreaticoduodenectomy(PD). DGE represents impaired gastric motility without significant mechanical obstruction and is associate...Background: Delayed gastric emptying(DGE) is one of the most common complications after pancreaticoduodenectomy(PD). DGE represents impaired gastric motility without significant mechanical obstruction and is associated with an increased length of hospital stay, increased healthcare costs, and a high readmission rate. We reviewed published studies on various technical modifications to reduce the incidence of DGE. Data sources: Studies were identified by searching Pub Med for relevant articles published up to December 2022. The following search terms were used: “pancreaticoduodenectomy”, “pancreaticojejunostomy”, “pancreaticogastrostomy”, “gastric emptying”, “gastroparesis” and “postoperative complications”. The search was limited to English publications. Additional articles were identified by a manual search of references from key articles. Results: In recent years, various surgical procedures and techniques have been explored to reduce the incidence of DGE. Pyloric resection, Billroth II reconstruction, Braun's enteroenterostomy, and antecolic reconstruction may be associated with a decreased incidence of DGE, but more high-powered studies are needed in the future. Neither laparoscopic nor robotic surgery has demonstrated superiority in preventing DGE, and the use of staplers is controversial regarding whether they can reduce the incidence of DGE. Conclusions: Despite many innovations in surgical techniques, there is no surgical procedure that is superior to others to reduce DGE. Further larger prospective randomized studies are needed.展开更多
In quantum computation and quantum information processing, the manipulation and engineering of quantum systems to suit certain purposes are an ongoing task. One such example is quantum state transfer(QST), an essentia...In quantum computation and quantum information processing, the manipulation and engineering of quantum systems to suit certain purposes are an ongoing task. One such example is quantum state transfer(QST), an essential requirement for both quantum communication and large-scale quantum computation. Here we engineer a chain of four superconducting qubits with tunable couplers to realize the perfect state transfer(PST) protocol originally proposed in quantum spin networks and successfully demonstrate the efficient transfer of an arbitrary single-qubit state from one end of the chain to the other,achieving a high fidelity of 0.986 in just 25 ns. This demonstrated QST is readily to extend to larger chain and multi-node configurations, thus serving as a desirable tool for scalable quantum information processing.展开更多
Conventional four-probe methods for measuring the resistance of Josephson junctions can damage superconducting thin films,making them unsuitable for frequency measurements of superconducting qubits.In this study,we pr...Conventional four-probe methods for measuring the resistance of Josephson junctions can damage superconducting thin films,making them unsuitable for frequency measurements of superconducting qubits.In this study,we present a custom probe station measurement system that employs the fritting contact technique to achieve in situ,non-destructive measurements of Josephson junction resistance.Our experimental results demonstrate that this method allows for accurate prediction of qubit frequency with an error margin of 17.2 MHz.Moreover,the fritting contact technique does not significantly affect qubit coherence time or the integrity of the superconducting film,confirming its non-destructive nature.This innovative approach provides a dependable foundation for frequency tuning and addressing frequency collision issues,thus supporting the advancement and practical deployment of superconducting quantum computing.展开更多
Accumulating epidemiological evidence shows that handgrip strength provides predictive potential in physical,mental,and reproductive health status.However,the associations between handgrip strength and semen character...Accumulating epidemiological evidence shows that handgrip strength provides predictive potential in physical,mental,and reproductive health status.However,the associations between handgrip strength and semen characteristics have not been explored.We recruited 1382 eligible men at the Hubei Province Human Sperm Bank(Wuhan,China)who had their handgrip strength measured at recruitment and provided 6458 repeated semen specimens within a 6-month period.Semen characteristics,including semen volume,sperm motility parameters(immotility,nonprogressive motility,and progressive motility),and sperm concentration,were assessed.Mixed-effect models and restricted cubic spline functions were applied to investigate the relationship of handgrip strength with repeated measurements of semen characteristics.After adjusting for confounding factors,the mixed-effect models revealed that handgrip strength was positively associated with semen volume,sperm concentration,progressive motility,total motility,and total count(all P for trend<0.05).Compared to men in the lowest quartile,those in the highest quartile of handgrip strength had higher semen volume,sperm concentration,progressive motility,total motility,and total count,with measurements of 14.2%(95%confidence interval[CI]:5.9%-23.2%),19.5%(95%CI:7.3%-33.1%),9.5%(95%CI:3.4%-15.9%),8.8%(95%CI:3.2%-14.6%),and 36.4%(95%CI:18.9%-56.5%),respectively.These positive dose-response relationships were further confirmed in restricted cubic splines,where handgrip strength was modeled as a continuous variable.Handgrip strength,as an indicator of muscular function and strength,was positively associated with semen characteristics in a dose-dependentmanner.展开更多
基金the National Natural Science Foun-dation of China(Grant Nos.12034018 and 11625419).
文摘The performance of Nb superconducting quantum devices is predominantly limited by dielectric loss at the metal–air interface,where Nb2O5 is considered the main loss source.Here,we suppress the formation of native oxides by in-situ deposition of a TiN capping layer on the Nb film.With TiN capping layers,no Nb2O5 forms on the surface of the Nb film.The quality factor Qi of the Nb resonator increases from 5.6×10^(5) to 7.9×10^(5) at low input power and from 6.8×10^(6) to 1.1×10^(7)at high input power.Furthermore,the TiN capping layer also shows good aging resistance in Nb resonator devices,with no significant performance fluctuations after one month of aging.These findings highlight the effectiveness of TiN capping layers in enhancing the performance and longevity of Nb superconducting quantum devices.
基金the National Natural Science Foun-dation of China(Grant Nos.12034018 and 11625419).
文摘Reducing the control error is vital for high-fidelity digital and analog quantum operations.In superconducting circuits,one disagreeable error arises from the reflection of microwave signals due to impedance mismatch in the control chain.Here,we demonstrate a reflection cancelation method when considering that there are two reflection nodes on the control line.We propose to generate the pre-distortion pulse by passing the envelopes of the microwave signal through digital filters,which enables real-time reflection correction when integrated into the field-programmable gate array(FPGA).We achieve a reduction of single-qubit gate infidelity from 0.67%to 0.11%after eliminating microwave reflection.Real-time correction of microwave reflection paves the way for precise control and manipulation of the qubit state and would ultimately enhance the performance of algorithms and simulations executed on quantum processors.
基金supported by the Opening Fund of Shandong Provincial Key Laboratory of Network based Intelligent Computing,the National Natural Science Foundation of China(52205529,61803192)the Natural Science Foundation of Shandong Province(ZR2021QE195)+1 种基金the Youth Innovation Team Program of Shandong Higher Education Institution(2023KJ206)the Guangyue Youth Scholar Innovation Talent Program support received from Liaocheng University(LCUGYTD2022-03).
文摘Effective path planning is crucial for mobile robots to quickly reach rescue destination and complete rescue tasks in a post-disaster scenario.In this study,we investigated the post-disaster rescue path planning problem and modeled this problem as a variant of the travel salesman problem(TSP)with life-strength constraints.To address this problem,we proposed an improved iterated greedy(IIG)algorithm.First,a push-forward insertion heuristic(PFIH)strategy was employed to generate a high-quality initial solution.Second,a greedy-based insertion strategy was designed and used in the destruction-construction stage to increase the algorithm’s exploration ability.Furthermore,three problem-specific swap operators were developed to improve the algorithm’s exploitation ability.Additionally,an improved simulated annealing(SA)strategy was used as an acceptance criterion to effectively prevent the algorithm from falling into local optima.To verify the effectiveness of the proposed algorithm,the Solomon dataset was extended to generate 27 instances for simulation.Finally,the proposed IIG was compared with five state-of-the-art algorithms.The parameter analysiswas conducted using the design of experiments(DOE)Taguchi method,and the effectiveness analysis of each component has been verified one by one.Simulation results indicate that IIGoutperforms the compared algorithms in terms of the number of rescue survivors and convergence speed,proving the effectiveness of the proposed algorithm.
文摘Background: Delayed gastric emptying(DGE) is one of the most common complications after pancreaticoduodenectomy(PD). DGE represents impaired gastric motility without significant mechanical obstruction and is associated with an increased length of hospital stay, increased healthcare costs, and a high readmission rate. We reviewed published studies on various technical modifications to reduce the incidence of DGE. Data sources: Studies were identified by searching Pub Med for relevant articles published up to December 2022. The following search terms were used: “pancreaticoduodenectomy”, “pancreaticojejunostomy”, “pancreaticogastrostomy”, “gastric emptying”, “gastroparesis” and “postoperative complications”. The search was limited to English publications. Additional articles were identified by a manual search of references from key articles. Results: In recent years, various surgical procedures and techniques have been explored to reduce the incidence of DGE. Pyloric resection, Billroth II reconstruction, Braun's enteroenterostomy, and antecolic reconstruction may be associated with a decreased incidence of DGE, but more high-powered studies are needed in the future. Neither laparoscopic nor robotic surgery has demonstrated superiority in preventing DGE, and the use of staplers is controversial regarding whether they can reduce the incidence of DGE. Conclusions: Despite many innovations in surgical techniques, there is no surgical procedure that is superior to others to reduce DGE. Further larger prospective randomized studies are needed.
基金Project supported by the National Natural Science Foundation of China (Grant Nos. 12034018 and 11625419)。
文摘In quantum computation and quantum information processing, the manipulation and engineering of quantum systems to suit certain purposes are an ongoing task. One such example is quantum state transfer(QST), an essential requirement for both quantum communication and large-scale quantum computation. Here we engineer a chain of four superconducting qubits with tunable couplers to realize the perfect state transfer(PST) protocol originally proposed in quantum spin networks and successfully demonstrate the efficient transfer of an arbitrary single-qubit state from one end of the chain to the other,achieving a high fidelity of 0.986 in just 25 ns. This demonstrated QST is readily to extend to larger chain and multi-node configurations, thus serving as a desirable tool for scalable quantum information processing.
基金Project supported by the National Natural Science Foundation of China(Grant Nos.12034018 and 11625419).
文摘Conventional four-probe methods for measuring the resistance of Josephson junctions can damage superconducting thin films,making them unsuitable for frequency measurements of superconducting qubits.In this study,we present a custom probe station measurement system that employs the fritting contact technique to achieve in situ,non-destructive measurements of Josephson junction resistance.Our experimental results demonstrate that this method allows for accurate prediction of qubit frequency with an error margin of 17.2 MHz.Moreover,the fritting contact technique does not significantly affect qubit coherence time or the integrity of the superconducting film,confirming its non-destructive nature.This innovative approach provides a dependable foundation for frequency tuning and addressing frequency collision issues,thus supporting the advancement and practical deployment of superconducting quantum computing.
基金supported by the National Natural Science Foundation of China(No.81903281)the National Postdoctoral Program for Innovative Talents(No.BX201700087)the Health Commission of Hubei Province Scientific Research Project(No.WJ2019H270).
文摘Accumulating epidemiological evidence shows that handgrip strength provides predictive potential in physical,mental,and reproductive health status.However,the associations between handgrip strength and semen characteristics have not been explored.We recruited 1382 eligible men at the Hubei Province Human Sperm Bank(Wuhan,China)who had their handgrip strength measured at recruitment and provided 6458 repeated semen specimens within a 6-month period.Semen characteristics,including semen volume,sperm motility parameters(immotility,nonprogressive motility,and progressive motility),and sperm concentration,were assessed.Mixed-effect models and restricted cubic spline functions were applied to investigate the relationship of handgrip strength with repeated measurements of semen characteristics.After adjusting for confounding factors,the mixed-effect models revealed that handgrip strength was positively associated with semen volume,sperm concentration,progressive motility,total motility,and total count(all P for trend<0.05).Compared to men in the lowest quartile,those in the highest quartile of handgrip strength had higher semen volume,sperm concentration,progressive motility,total motility,and total count,with measurements of 14.2%(95%confidence interval[CI]:5.9%-23.2%),19.5%(95%CI:7.3%-33.1%),9.5%(95%CI:3.4%-15.9%),8.8%(95%CI:3.2%-14.6%),and 36.4%(95%CI:18.9%-56.5%),respectively.These positive dose-response relationships were further confirmed in restricted cubic splines,where handgrip strength was modeled as a continuous variable.Handgrip strength,as an indicator of muscular function and strength,was positively associated with semen characteristics in a dose-dependentmanner.
