The quantum geometric tensor(QGT)is a fundamental quantity for characterizing the geometric properties of quantum states and plays an essential role in elucidating various physical phenomena.The traditional QGT,defned...The quantum geometric tensor(QGT)is a fundamental quantity for characterizing the geometric properties of quantum states and plays an essential role in elucidating various physical phenomena.The traditional QGT,defned only for pure states,has limited applicability in realistic scenarios where mixed states are common.To address this limitation,we generalize the defnition of the QGT to mixed states using the purifcation bundle and the covariant derivative.Notably,our proposed defnition reduces to the traditional QGT when mixed states approach pure states.In our framework,the real and imaginary parts of this generalized QGT correspond to the Bures metric and the mean gauge curvature,respectively,endowing it with a broad range of potential applications.Additionally,using our proposed mixed-state QGT,we derive the geodesic equation applicable to mixed states.This work establishes a unifed framework for the geometric analysis of both pure and mixed states,thereby deepening our understanding of the geometric properties of quantum states.展开更多
In practical engineering applications,composite laminates frequently encounter complex multiple low-velocity impact events.The damage coupling caused by the different Angles Between Impact Positions(ABIP)is a key fact...In practical engineering applications,composite laminates frequently encounter complex multiple low-velocity impact events.The damage coupling caused by the different Angles Between Impact Positions(ABIP)is a key factor in reducing the load-bearing capacity of the laminates.It is worth noting that in real impact events,the delamination damage information of laminates is easier to capture directly.Therefore,it is crucial to predict the damage tolerance of laminates by analyzing their delamination damage images.This paper adopts an integrated finite element model to present an in-depth study on the damage characteristics and Compression-After-Impact(CAI)strength of carbon/glass hybrid laminates subjected to multiple low-velocity impacts at different ABIP.By leveraging the recognition capabilities of Convolutional Neural Networks(CNN)and taking into account the impact of noise,it aims to establish the implicit mapping relationship between delamination damage images and impact parameters,as well as CAI strength.This approach facilitates the inverse inversion of impact parameters for multiple low-velocity impacts of laminates under different ABIP,as well as effective prediction of CAI strength.展开更多
Primary liver cancer,a common malignant tumor of the digestive tract,ranks fifth in global cancer incidence and shows high morbidity and mortality.Liver cancer patients who are diagnosed early have the option of surgi...Primary liver cancer,a common malignant tumor of the digestive tract,ranks fifth in global cancer incidence and shows high morbidity and mortality.Liver cancer patients who are diagnosed early have the option of surgical resection,which offers the possibility of a radical cure.However,due to the insidious disease onset,most patients are diagnosed in the intermediate or advanced stages,and surgery is no longer a viable option.Therefore,systemic treatment options play an essential role in the management of advanced liver cancer.These treatments aim to suppress disease progression,prolong survival,and improve quality of life.This article reviews the latest research in the field of systemic therapy of liver cancer,including molecular targeted therapy,immunotherapy,and their combination strategies.At first,the application and efficacy of first-line molecularly targeted drugs are discussed.Next,the revolutionary advances in immune checkpoint blockers are presented.Subsequently,the clinical effects of the combination of molecularly targeted therapy and immunotherapy are analyzed.Finally,this article summarizes the current challenges faced by the systemic treatment of liver cancer and introduces the prospect of future treatment trends.展开更多
With the rapid development of software engineering,traditional teaching methods are confronted with the challenges of short knowledge update cycles and the rapid emergence of new technologies.By analyzing the current ...With the rapid development of software engineering,traditional teaching methods are confronted with the challenges of short knowledge update cycles and the rapid emergence of new technologies.By analyzing the current situation of the mismatch between educational practices and industrial change,this study proposes an innovative teaching model—“Micro-practices”.This model integrates new knowledge and new technologies into the teaching process quickly and flexibly through practical teaching projects with“short class time,small capacity,and cloud environment”to meet the different educational needs of students,teachers,and enterprises.The aim is to train innovative software engineering talents who can meet the challenges of the future.展开更多
AIM To prospectively evaluate the effect of local wound infiltration with ropivacaine on postoperative pain relief and stress response reduction after open hepatectomy.METHODS A total of 56 patients undergoing open he...AIM To prospectively evaluate the effect of local wound infiltration with ropivacaine on postoperative pain relief and stress response reduction after open hepatectomy.METHODS A total of 56 patients undergoing open hepatectomy were randomly divided into two groups:a ropivacaine group(wound infiltration with ropivacaine solution)and a control group(infiltration with isotonic saline solution).A visual analog scale(VAS)at rest and on movement was used to measure postoperative pain for the first 48 h after surgery.Mean arterial pressure(MAP),heart rate(HR),time to bowel recovery,length of hospitalization after surgery,cumulative sufentanil consumption,and incidence of nausea and vomiting were compared between the two groups.Surgical stress hormones(epinephrine,norepinephrine,and cortisol)were detected using enzyme-linked immunosorbent assay,and the results were compared. RESULTS VAS scores both at rest and on movement at 24 h and48 h were similar between the two groups.Significantly lower VAS scores were detected at 0,6,and 12 h in the ropivacaine group compared with the control group(P<0.05 for all).MAP was significantly lower at 6,12,and 24 h(P<0.05 for all);HR was significantly lower at 0,6,12,and 24 h(P<0.05 for all);time to bowel recovery and length of hospitalization after surgery(P<0.05 for both)were significantly shortened;and cumulative sufentanil consumption was significantly lower at 6,12,24,and 36 h(P<0.05 for all)in the ropivacaine group than in the control group,although the incidence of nausea and vomiting showed no significant difference between the two groups.The levels of epinephrine,norepinephrine,and cortisol were significantly lower in the ropivacaine group than in the control group at 24 and 48 h(P<0.01 for all). CONCLUSION Local wound infiltration with ropivacaine after open hepatectomy can improve postoperative pain relief,reduce surgical stress response,and accelerate postoperative recovery.展开更多
AIM:To access the efficacy of combination with amoxicillin and tetracycline for eradication of Helicobacter pylori(H.pylori),thus providing clinical practice guidelines.METHODS:Pub Med,EMBASE,Cochrane Central Register...AIM:To access the efficacy of combination with amoxicillin and tetracycline for eradication of Helicobacter pylori(H.pylori),thus providing clinical practice guidelines.METHODS:Pub Med,EMBASE,Cochrane Central Register of Controlled Trials,Science Citation Index,China National Knowledge Infrastructure,Wanfang,and Chinese Biomedical Literature databases and abstract books of major European,American,and Asian gastroenterological meetings were searched.All clinical trials that examined the efficacy of H.pylori eradication therapies and included both tetracycline and amoxicillin in one study arm were selected for this systematic review and meta-analysis.Statistical analysis was performed with Comprehensive Meta-Analysis Software(Version 2).Subgroup,meta-regression,and sensitivity analyses were also carried out.RESULTS:Thirty-three studies met the inclusion criteria.The pooled odds ratio(OR)was 0.90(95%CI:0.42-1.78)for quadruple therapy with amoxicillin and tetracycline vs other quadruple regimens,and total eradication rates were 78.1%by intention-to-treat(ITT)and 84.5%by per-protocol(PP)analyses in the experimental groups.The pooled eradication rates of 14-d quadruple regimens with a combination of amoxicillin and tetracycline were 82.3%by ITT and89.0%by PP,and those of 10-d regimens were 84.6%by ITT and 93.7%by PP.The OR by ITT were 1.21(95%CI:0.64-2.28)for triple regimens with amoxicillin and tetracycline vs other regimens and 1.81(95%CI:1.37-2.41)for sequential treatment with amoxicillin and tetracycline vs other regimens,respectively.CONCLUSION:The effectiveness of regimens employing amoxicillin and tetracycline for H.pylori eradication may be not inferior to other regimens,but further study should be necessary.展开更多
Medical models, or ＂phantoms,＂ have been widely used for medical training and for doctor-patient interactions. They are increasingly used for surgical planning, medical computational models, algorithm verification a...Medical models, or ＂phantoms,＂ have been widely used for medical training and for doctor-patient interactions. They are increasingly used for surgical planning, medical computational models, algorithm verification and validation, and medical devices development. Such new applications demand high-fidelity, patient-specific, tissue-mimicking medical phantoms that can not only closely emulate the geometric structures of human organs, but also possess the properties and functions of the organ structure. With the rapid advancement of three-dimensional （3D） printing and 3D bioprinting technologies, many researchers have explored the use of these additive manufacturing techniques to fabricate functional medical phantoms for various applications. This paper reviews the applications of these 3D printing and 3D bioprinting technologies for the fabrication of functional medical phantoms and bio-structures. This review specifically discusses the state of the art along with new developments and trends in 3D printed functional medical phantoms （i.e., tissue-mimicking medical phantoms, radiologically relevant medical phantoms, and physiological medical phantoms） and 3D bio-printed structures （i.e., hybrid scaffolding materials, convertible scaffolds, and integrated sensors） for regenerated tissues and organs.展开更多
The aim of this study was to determine the attenuation of gamma and X-rays with different energies caused by passage through different materials.To this end,different materials with a range of atomic numbers were chos...The aim of this study was to determine the attenuation of gamma and X-rays with different energies caused by passage through different materials.To this end,different materials with a range of atomic numbers were chosen to measure gamma and X-ray attenuation coefficients and to explore the mechanisms of interaction of gamma and X-rays with matter of various kinds.It is shown that the attenuation coefficients first decrease and then increase with increase in the radiation(photon)energy.The attenuation of gamma and X-rays passing through materials with high atomic number is greater than that in materials with low atomic number.The attenuation minimum is related to the atomic number of the irradiated materials.The larger the atomic number is,the lower the energy corresponding to attenuation minimum is.Photoelectric and Compton effects are the main processes when gamma rays pass through individual materials with high and low atomic numbers,respectively.Therefore,for radiotherapy and radiation protection,different methods should be considered and selected for the use of gamma and X-rays of different energies for use in different materials.展开更多
The mechanical characteristics and acoustic behavior of rock masses are greatly influenced by stochastic joints.In this study,numerical models of rock masses incorporating intermittent joints with different numbers an...The mechanical characteristics and acoustic behavior of rock masses are greatly influenced by stochastic joints.In this study,numerical models of rock masses incorporating intermittent joints with different numbers and dip angles were produced using the finite element method(FEM)with the intrinsic cohesive zone model(ICZM).Then,the uniaxial compressive and wave propagation simulations were performed.The results indicate that the joint number and dip angle can affect the mechanical and acoustic properties of the models.The uniaxial compressive strength(UCS)and wave velocity of rock masses decrease monotonically as the joint number increases.However,the wave velocity grows monotonically as the joint dip angle increases.When the joint dip angle is 45°–60°,the UCS of the rock mass is lower than that of other dip angles.The wave velocity parallel to the joints is greater than that perpendicular to the joints.When the dip angle of joints remains unchanged,the UCS and wave velocity are positively related.When the joint dip angle increases,the variation amplitude of the UCS regarding the wave velocity increases.To reveal the effect of the joint distribution on the velocity,a theoretical model was also proposed.According to the theoretical wave velocity,the change in wave velocity of models with various joint numbers and dip angles was consistent with the simulation results.Furthermore,a theoretical indicator(i.e.fabric tensor)was adopted to analyze the variation of the wave velocity and UCS.展开更多
Wet dust removal systems used to control dust in the polishing or grinding process of Mg alloy products are frequently associated with potential hydrogen explosion caused by magnesium-water reaction.For purpose of avo...Wet dust removal systems used to control dust in the polishing or grinding process of Mg alloy products are frequently associated with potential hydrogen explosion caused by magnesium-water reaction.For purpose of avoiding hydrogen explosion risks,we try to use a combination of chitosan(CS)and sodium phosphate(SP)to inhibit the hydrogen evolution reaction between magnesium alloy waste dust and water.The hydrogen evolution curves and chemical kinetics modeling for ten different mixing ratios demonstrate that 0.4wt%CS+0.1wt%SP yields the best inhibition efficiency with hydrogen generation rate of almost zero.SEM and EDS analyses indicate that this composite inhibitor can create a uniform,smooth,tight protective film over the surface of the alloy dust particles.FTIR and XRD analysis of the chemical composition of the surface film show that this protective film contains CS and SP chemically adsorbed on the surface of ZK60 but no detectable Mg(OH)_(2),suggesting that magnesium-water reaction was totally blocked.Our new method offers a thorough solution to hydrogen explosion by inhibiting the hydrogen generation of magnesium alloy waste dust in a wet dust removal system.展开更多
Structural connections between components are often weak areas in engineering applications.In nature,many biological materials with remarkablemechanical performance possess flexible and creative sutures.In this work,w...Structural connections between components are often weak areas in engineering applications.In nature,many biological materials with remarkablemechanical performance possess flexible and creative sutures.In this work,we propose a novel bioinspired interlocking tab considering both the geometry of the tab head and neck,and demonstrate a new approach to optimize the bio-inspired interlocking structures based on machine learning.Artificial neural networks for different optimization objectives are developed and trained using a database of thousands of interlocking structures generated through finite element analysis.Results show that the proposed method is able to achieve accurate prediction of the mechanical response of any given interlocking tab.The optimized designs with different optimization objectives,such as strength,stiffness,and toughness,are obtained efficiently and precisely.The optimum design predicted by machine learning is approximately 7.98 times stronger and 2.98 times tougher than the best design in the training set,which are validated through additive manufacturing and experimental testing.The machine learning-based optimization approach developed here can aid in the exploration of the intricate mechanism behind biological materials and the discovery of new material designs boasting orders of magnitude increase in computational efficacy over conventional methods.展开更多
For advanced conductive hydrogels,adaptable mechanical properties and high conductivity are essential requirements for practical application,e.g.,soft electronic devices.Here,a straightforward strategy to develop a me...For advanced conductive hydrogels,adaptable mechanical properties and high conductivity are essential requirements for practical application,e.g.,soft electronic devices.Here,a straightforward strategy to develop a mechanically robust hydrogel with high conductivity by constructing complicated 3D structures composed of covalently cross-linked polymer network and two nanofillers with distinguishing dimensions is reported.The combination of one-dimensional quaternized cellulose nanofibrils(QACNF)and two-dimensional MXene nanosheets not only provides prominent and tunable mechanical properties modulated by materials composition,but results in electronically conductive path with high conductivity(1281 mS m^(-1)).Owing to the uniform interconnectivity of network structure attributed to the strong macro-molecular interaction and nano-reinforced effect,the resultant hydrogel exhibits a balanced mechanical feature,i.e.,high tensile strength(449 kPa),remarkable stretchability(>1700%),and ultra-high toughness(5.46 MJ m^(-3)),outperforming those of virgin one.Additionally,the enhanced conductive characteristic with the aid of QACNF enables hydrogels with impressive electromechanical behavior,containing high sensitivity(maximum gauge factor:2.24),wide working range(0-1465%),and fast response performance(response time:141 ms,recover time:140 ms).Benefiting from the excellent mechanical performance,a flexible strain sensor based on such conductive hydrogel can deliver an appealing sensing performance of monitoring multi-scale deformations,from large and monotonous mechanical deformation to tiny and complex physiological motions(e.g.,joint movement and signature/vocal recognition).Together,the hydrogel material in this work opens up opportunities in the design and fabrication of advanced gel-based materials for emerging wearable electronics.展开更多
[ Objective ] This study aimed to provide basic data for studying the relationship between structure and property of cellulose microspheres by measuring molecular weight of cellulose and cellulose microspheres with vi...[ Objective ] This study aimed to provide basic data for studying the relationship between structure and property of cellulose microspheres by measuring molecular weight of cellulose and cellulose microspheres with viscosity method and gel permeation chromatography （GPC） method. [ Method] In viscosity method, cadmium ethylenediamine was used as the solvent, intrinsic viscosity η of the solution was determined at 25 ℃ by using a Ubbelohde viscometer, to calculate the molecular weight of cellulose; in GPC method, 8% LiC1 / N, N-dimethylacetamide （LiC1/DMAc） was used as the solvent and 0.5% LiC1/DMAc was used as the mobile phase to determine the relative molecular weight and distribution of cellulose and cellulose microspheres. In addition, the determination results were analyzed to compare these two methods. [ Result ] Viscosity-average molecular weight Mr/ of cellulose and cellulose microspheres determined with viscosity method were 224,532 and 16,686, respectively; weight-average molecular weight Mw of cellulose and cellulose microspheres determined with GPC method were 284,196 and 22,345, respectively. [ Conclusion] The determination results of （;PC method are relatively close to the actual value and could truly reflect the characteristics of molecular weialat distribution of eellulose and cellulose mierosr, heres.展开更多
Many articles have been published on intelligent manufacturing, most of which focus on hardware, soft-ware, additive manufacturing, robotics, the Internet of Things, and Industry 4.0. This paper provides a dif-ferent ...Many articles have been published on intelligent manufacturing, most of which focus on hardware, soft-ware, additive manufacturing, robotics, the Internet of Things, and Industry 4.0. This paper provides a dif-ferent perspective by examining relevant challenges and providing examples of some less-talked-about yet essential topics, such as hybrid systems, redefining advanced manufacturing, basic building blocks of new manufacturing, ecosystem readiness, and technology scalahility. The first major challenge is to （re-）define what the manufacturing of the future will he, if we wish to： ① raise public awareness of new manufacturing＇s economic and societal impacts, and ② garner the unequivocal support of policy- makers. The second major challenge is to recognize that manufacturing in the future will consist of sys-tems of hybrid systems of human and robotic operators; additive and suhtractive processes; metal and composite materials; and cyher and physical systems. Therefore, studying the interfaces between con- stituencies and standards becomes important and essential. The third challenge is to develop a common framework in which the technology, manufacturing business case, and ecosystem readiness can he eval- uated concurrently in order to shorten the time it takes for products to reach customers. Integral to this is having accepted measures of ＂scalahility＂ of non-information technologies. The last, hut not least, chal-lenge is to examine successful modalities of industry-academia-government collaborations through public-private partnerships. This article discusses these challenges in detail.展开更多
基金supported by the National Natural Science Foundation of China(Grant Nos.12347104,U24A2017,12461160276,and 12175075)the National Key Research and Development Program of China(Grant No.2023YFC2205802)+1 种基金the Natural Science Foundation of Jiangsu Province(Grant Nos.BK20243060 and BK20233001)in part by the State Key Laboratory of Advanced Optical Communication Systems and Networks,China。
文摘The quantum geometric tensor(QGT)is a fundamental quantity for characterizing the geometric properties of quantum states and plays an essential role in elucidating various physical phenomena.The traditional QGT,defned only for pure states,has limited applicability in realistic scenarios where mixed states are common.To address this limitation,we generalize the defnition of the QGT to mixed states using the purifcation bundle and the covariant derivative.Notably,our proposed defnition reduces to the traditional QGT when mixed states approach pure states.In our framework,the real and imaginary parts of this generalized QGT correspond to the Bures metric and the mean gauge curvature,respectively,endowing it with a broad range of potential applications.Additionally,using our proposed mixed-state QGT,we derive the geodesic equation applicable to mixed states.This work establishes a unifed framework for the geometric analysis of both pure and mixed states,thereby deepening our understanding of the geometric properties of quantum states.
基金supported by the National Natural Science Foundation of China(Nos.12372068 and 12202066)。
文摘In practical engineering applications,composite laminates frequently encounter complex multiple low-velocity impact events.The damage coupling caused by the different Angles Between Impact Positions(ABIP)is a key factor in reducing the load-bearing capacity of the laminates.It is worth noting that in real impact events,the delamination damage information of laminates is easier to capture directly.Therefore,it is crucial to predict the damage tolerance of laminates by analyzing their delamination damage images.This paper adopts an integrated finite element model to present an in-depth study on the damage characteristics and Compression-After-Impact(CAI)strength of carbon/glass hybrid laminates subjected to multiple low-velocity impacts at different ABIP.By leveraging the recognition capabilities of Convolutional Neural Networks(CNN)and taking into account the impact of noise,it aims to establish the implicit mapping relationship between delamination damage images and impact parameters,as well as CAI strength.This approach facilitates the inverse inversion of impact parameters for multiple low-velocity impacts of laminates under different ABIP,as well as effective prediction of CAI strength.
基金Supported by the Science and Technology Project of China-Shaanxi Nuclear Industry Group,No.61230303the Shaanxi Nuclear Industry 215 Hospital Scientific Research Project,No.215KYJJ-202214+1 种基金the Science and Technology Plan Project of Jiangxi Provincial Health CommissionNo.202510800.
文摘Primary liver cancer,a common malignant tumor of the digestive tract,ranks fifth in global cancer incidence and shows high morbidity and mortality.Liver cancer patients who are diagnosed early have the option of surgical resection,which offers the possibility of a radical cure.However,due to the insidious disease onset,most patients are diagnosed in the intermediate or advanced stages,and surgery is no longer a viable option.Therefore,systemic treatment options play an essential role in the management of advanced liver cancer.These treatments aim to suppress disease progression,prolong survival,and improve quality of life.This article reviews the latest research in the field of systemic therapy of liver cancer,including molecular targeted therapy,immunotherapy,and their combination strategies.At first,the application and efficacy of first-line molecularly targeted drugs are discussed.Next,the revolutionary advances in immune checkpoint blockers are presented.Subsequently,the clinical effects of the combination of molecularly targeted therapy and immunotherapy are analyzed.Finally,this article summarizes the current challenges faced by the systemic treatment of liver cancer and introduces the prospect of future treatment trends.
基金funded by Universityindustry Collaborative Education Program(No.220605181024725)the Undergraduate Education and Teaching Reform Research Project of Northwestern Polytechnical University(No.22GZ13083)。
文摘With the rapid development of software engineering,traditional teaching methods are confronted with the challenges of short knowledge update cycles and the rapid emergence of new technologies.By analyzing the current situation of the mismatch between educational practices and industrial change,this study proposes an innovative teaching model—“Micro-practices”.This model integrates new knowledge and new technologies into the teaching process quickly and flexibly through practical teaching projects with“short class time,small capacity,and cloud environment”to meet the different educational needs of students,teachers,and enterprises.The aim is to train innovative software engineering talents who can meet the challenges of the future.
基金Supported by National Natural Science foundation of China,No.81571367 and No.81502050Scientific and Technological Project of Shandong Province,No.2016GSf201082
文摘AIM To prospectively evaluate the effect of local wound infiltration with ropivacaine on postoperative pain relief and stress response reduction after open hepatectomy.METHODS A total of 56 patients undergoing open hepatectomy were randomly divided into two groups:a ropivacaine group(wound infiltration with ropivacaine solution)and a control group(infiltration with isotonic saline solution).A visual analog scale(VAS)at rest and on movement was used to measure postoperative pain for the first 48 h after surgery.Mean arterial pressure(MAP),heart rate(HR),time to bowel recovery,length of hospitalization after surgery,cumulative sufentanil consumption,and incidence of nausea and vomiting were compared between the two groups.Surgical stress hormones(epinephrine,norepinephrine,and cortisol)were detected using enzyme-linked immunosorbent assay,and the results were compared. RESULTS VAS scores both at rest and on movement at 24 h and48 h were similar between the two groups.Significantly lower VAS scores were detected at 0,6,and 12 h in the ropivacaine group compared with the control group(P<0.05 for all).MAP was significantly lower at 6,12,and 24 h(P<0.05 for all);HR was significantly lower at 0,6,12,and 24 h(P<0.05 for all);time to bowel recovery and length of hospitalization after surgery(P<0.05 for both)were significantly shortened;and cumulative sufentanil consumption was significantly lower at 6,12,24,and 36 h(P<0.05 for all)in the ropivacaine group than in the control group,although the incidence of nausea and vomiting showed no significant difference between the two groups.The levels of epinephrine,norepinephrine,and cortisol were significantly lower in the ropivacaine group than in the control group at 24 and 48 h(P<0.01 for all). CONCLUSION Local wound infiltration with ropivacaine after open hepatectomy can improve postoperative pain relief,reduce surgical stress response,and accelerate postoperative recovery.
基金Supported by Grants from National Science and Technology Major Projects for"Major New Drugs Innovation and Development"of China,No.2011ZX09302-007-03
文摘AIM:To access the efficacy of combination with amoxicillin and tetracycline for eradication of Helicobacter pylori(H.pylori),thus providing clinical practice guidelines.METHODS:Pub Med,EMBASE,Cochrane Central Register of Controlled Trials,Science Citation Index,China National Knowledge Infrastructure,Wanfang,and Chinese Biomedical Literature databases and abstract books of major European,American,and Asian gastroenterological meetings were searched.All clinical trials that examined the efficacy of H.pylori eradication therapies and included both tetracycline and amoxicillin in one study arm were selected for this systematic review and meta-analysis.Statistical analysis was performed with Comprehensive Meta-Analysis Software(Version 2).Subgroup,meta-regression,and sensitivity analyses were also carried out.RESULTS:Thirty-three studies met the inclusion criteria.The pooled odds ratio(OR)was 0.90(95%CI:0.42-1.78)for quadruple therapy with amoxicillin and tetracycline vs other quadruple regimens,and total eradication rates were 78.1%by intention-to-treat(ITT)and 84.5%by per-protocol(PP)analyses in the experimental groups.The pooled eradication rates of 14-d quadruple regimens with a combination of amoxicillin and tetracycline were 82.3%by ITT and89.0%by PP,and those of 10-d regimens were 84.6%by ITT and 93.7%by PP.The OR by ITT were 1.21(95%CI:0.64-2.28)for triple regimens with amoxicillin and tetracycline vs other regimens and 1.81(95%CI:1.37-2.41)for sequential treatment with amoxicillin and tetracycline vs other regimens,respectively.CONCLUSION:The effectiveness of regimens employing amoxicillin and tetracycline for H.pylori eradication may be not inferior to other regimens,but further study should be necessary.
文摘Medical models, or ＂phantoms,＂ have been widely used for medical training and for doctor-patient interactions. They are increasingly used for surgical planning, medical computational models, algorithm verification and validation, and medical devices development. Such new applications demand high-fidelity, patient-specific, tissue-mimicking medical phantoms that can not only closely emulate the geometric structures of human organs, but also possess the properties and functions of the organ structure. With the rapid advancement of three-dimensional （3D） printing and 3D bioprinting technologies, many researchers have explored the use of these additive manufacturing techniques to fabricate functional medical phantoms for various applications. This paper reviews the applications of these 3D printing and 3D bioprinting technologies for the fabrication of functional medical phantoms and bio-structures. This review specifically discusses the state of the art along with new developments and trends in 3D printed functional medical phantoms （i.e., tissue-mimicking medical phantoms, radiologically relevant medical phantoms, and physiological medical phantoms） and 3D bio-printed structures （i.e., hybrid scaffolding materials, convertible scaffolds, and integrated sensors） for regenerated tissues and organs.
基金supported by the National Natural Science Foundation of China(Nos.11475013,11975040 and U1832130)
文摘The aim of this study was to determine the attenuation of gamma and X-rays with different energies caused by passage through different materials.To this end,different materials with a range of atomic numbers were chosen to measure gamma and X-ray attenuation coefficients and to explore the mechanisms of interaction of gamma and X-rays with matter of various kinds.It is shown that the attenuation coefficients first decrease and then increase with increase in the radiation(photon)energy.The attenuation of gamma and X-rays passing through materials with high atomic number is greater than that in materials with low atomic number.The attenuation minimum is related to the atomic number of the irradiated materials.The larger the atomic number is,the lower the energy corresponding to attenuation minimum is.Photoelectric and Compton effects are the main processes when gamma rays pass through individual materials with high and low atomic numbers,respectively.Therefore,for radiotherapy and radiation protection,different methods should be considered and selected for the use of gamma and X-rays of different energies for use in different materials.
基金financial support from the National Key R&D Program of China(Grant No.2020YFA0711802).
文摘The mechanical characteristics and acoustic behavior of rock masses are greatly influenced by stochastic joints.In this study,numerical models of rock masses incorporating intermittent joints with different numbers and dip angles were produced using the finite element method(FEM)with the intrinsic cohesive zone model(ICZM).Then,the uniaxial compressive and wave propagation simulations were performed.The results indicate that the joint number and dip angle can affect the mechanical and acoustic properties of the models.The uniaxial compressive strength(UCS)and wave velocity of rock masses decrease monotonically as the joint number increases.However,the wave velocity grows monotonically as the joint dip angle increases.When the joint dip angle is 45°–60°,the UCS of the rock mass is lower than that of other dip angles.The wave velocity parallel to the joints is greater than that perpendicular to the joints.When the dip angle of joints remains unchanged,the UCS and wave velocity are positively related.When the joint dip angle increases,the variation amplitude of the UCS regarding the wave velocity increases.To reveal the effect of the joint distribution on the velocity,a theoretical model was also proposed.According to the theoretical wave velocity,the change in wave velocity of models with various joint numbers and dip angles was consistent with the simulation results.Furthermore,a theoretical indicator(i.e.fabric tensor)was adopted to analyze the variation of the wave velocity and UCS.
基金This work was supported by the National Natural Science Foundation of China(52074066).
文摘Wet dust removal systems used to control dust in the polishing or grinding process of Mg alloy products are frequently associated with potential hydrogen explosion caused by magnesium-water reaction.For purpose of avoiding hydrogen explosion risks,we try to use a combination of chitosan(CS)and sodium phosphate(SP)to inhibit the hydrogen evolution reaction between magnesium alloy waste dust and water.The hydrogen evolution curves and chemical kinetics modeling for ten different mixing ratios demonstrate that 0.4wt%CS+0.1wt%SP yields the best inhibition efficiency with hydrogen generation rate of almost zero.SEM and EDS analyses indicate that this composite inhibitor can create a uniform,smooth,tight protective film over the surface of the alloy dust particles.FTIR and XRD analysis of the chemical composition of the surface film show that this protective film contains CS and SP chemically adsorbed on the surface of ZK60 but no detectable Mg(OH)_(2),suggesting that magnesium-water reaction was totally blocked.Our new method offers a thorough solution to hydrogen explosion by inhibiting the hydrogen generation of magnesium alloy waste dust in a wet dust removal system.
基金supported by the National Natural Science Foundation of China,Grant No.51875440.
文摘Structural connections between components are often weak areas in engineering applications.In nature,many biological materials with remarkablemechanical performance possess flexible and creative sutures.In this work,we propose a novel bioinspired interlocking tab considering both the geometry of the tab head and neck,and demonstrate a new approach to optimize the bio-inspired interlocking structures based on machine learning.Artificial neural networks for different optimization objectives are developed and trained using a database of thousands of interlocking structures generated through finite element analysis.Results show that the proposed method is able to achieve accurate prediction of the mechanical response of any given interlocking tab.The optimized designs with different optimization objectives,such as strength,stiffness,and toughness,are obtained efficiently and precisely.The optimum design predicted by machine learning is approximately 7.98 times stronger and 2.98 times tougher than the best design in the training set,which are validated through additive manufacturing and experimental testing.The machine learning-based optimization approach developed here can aid in the exploration of the intricate mechanism behind biological materials and the discovery of new material designs boasting orders of magnitude increase in computational efficacy over conventional methods.
基金supported by the National Natural Science Foundation of China(Nos.52203148,51973047,and 12002113)the Research Foundation of Talented Scholars of Zhejiang A&F University(Nos.2020FR070 and 2021FR024)+1 种基金the Zhejiang A&F University Scientific Research Training Program for Undergraduates(No.S202210341186)the Key Research and Development Program of Shaanxi(No.2022-JBGS3-09).
文摘For advanced conductive hydrogels,adaptable mechanical properties and high conductivity are essential requirements for practical application,e.g.,soft electronic devices.Here,a straightforward strategy to develop a mechanically robust hydrogel with high conductivity by constructing complicated 3D structures composed of covalently cross-linked polymer network and two nanofillers with distinguishing dimensions is reported.The combination of one-dimensional quaternized cellulose nanofibrils(QACNF)and two-dimensional MXene nanosheets not only provides prominent and tunable mechanical properties modulated by materials composition,but results in electronically conductive path with high conductivity(1281 mS m^(-1)).Owing to the uniform interconnectivity of network structure attributed to the strong macro-molecular interaction and nano-reinforced effect,the resultant hydrogel exhibits a balanced mechanical feature,i.e.,high tensile strength(449 kPa),remarkable stretchability(>1700%),and ultra-high toughness(5.46 MJ m^(-3)),outperforming those of virgin one.Additionally,the enhanced conductive characteristic with the aid of QACNF enables hydrogels with impressive electromechanical behavior,containing high sensitivity(maximum gauge factor:2.24),wide working range(0-1465%),and fast response performance(response time:141 ms,recover time:140 ms).Benefiting from the excellent mechanical performance,a flexible strain sensor based on such conductive hydrogel can deliver an appealing sensing performance of monitoring multi-scale deformations,from large and monotonous mechanical deformation to tiny and complex physiological motions(e.g.,joint movement and signature/vocal recognition).Together,the hydrogel material in this work opens up opportunities in the design and fabrication of advanced gel-based materials for emerging wearable electronics.
基金Supported by Natural Science Foundation of Guangxi(0991024Z)
文摘[ Objective ] This study aimed to provide basic data for studying the relationship between structure and property of cellulose microspheres by measuring molecular weight of cellulose and cellulose microspheres with viscosity method and gel permeation chromatography （GPC） method. [ Method] In viscosity method, cadmium ethylenediamine was used as the solvent, intrinsic viscosity η of the solution was determined at 25 ℃ by using a Ubbelohde viscometer, to calculate the molecular weight of cellulose; in GPC method, 8% LiC1 / N, N-dimethylacetamide （LiC1/DMAc） was used as the solvent and 0.5% LiC1/DMAc was used as the mobile phase to determine the relative molecular weight and distribution of cellulose and cellulose microspheres. In addition, the determination results were analyzed to compare these two methods. [ Result ] Viscosity-average molecular weight Mr/ of cellulose and cellulose microspheres determined with viscosity method were 224,532 and 16,686, respectively; weight-average molecular weight Mw of cellulose and cellulose microspheres determined with GPC method were 284,196 and 22,345, respectively. [ Conclusion] The determination results of （;PC method are relatively close to the actual value and could truly reflect the characteristics of molecular weialat distribution of eellulose and cellulose mierosr, heres.
文摘Many articles have been published on intelligent manufacturing, most of which focus on hardware, soft-ware, additive manufacturing, robotics, the Internet of Things, and Industry 4.0. This paper provides a dif-ferent perspective by examining relevant challenges and providing examples of some less-talked-about yet essential topics, such as hybrid systems, redefining advanced manufacturing, basic building blocks of new manufacturing, ecosystem readiness, and technology scalahility. The first major challenge is to （re-）define what the manufacturing of the future will he, if we wish to： ① raise public awareness of new manufacturing＇s economic and societal impacts, and ② garner the unequivocal support of policy- makers. The second major challenge is to recognize that manufacturing in the future will consist of sys-tems of hybrid systems of human and robotic operators; additive and suhtractive processes; metal and composite materials; and cyher and physical systems. Therefore, studying the interfaces between con- stituencies and standards becomes important and essential. The third challenge is to develop a common framework in which the technology, manufacturing business case, and ecosystem readiness can he eval- uated concurrently in order to shorten the time it takes for products to reach customers. Integral to this is having accepted measures of ＂scalahility＂ of non-information technologies. The last, hut not least, chal-lenge is to examine successful modalities of industry-academia-government collaborations through public-private partnerships. This article discusses these challenges in detail.
