Simple Network Management Protocol (SNMP) is the most widely used network management protocol on TCP/IP based networks. However, the lack of security features, notably authentication and privacy, is its weakness. To r...Simple Network Management Protocol (SNMP) is the most widely used network management protocol on TCP/IP based networks. However, the lack of security features, notably authentication and privacy, is its weakness. To rectify this deficiency, a new version of SNMP, known as SNMPv3, is presented. The principal security facilities defined in SNMPv3 which include timeliness mechanism, authentication, privacy and access control are outlined, and a example on how to implement security features in a practical software system is given.展开更多
Plant roots are widely known to provide mechanical reinforcement to soils against shearing and further increase slope stability.However,whether roots provide reinforcement to loess cyclic re-sistance and how various f...Plant roots are widely known to provide mechanical reinforcement to soils against shearing and further increase slope stability.However,whether roots provide reinforcement to loess cyclic re-sistance and how various factors affect roots reinforcement during seismic loading have rarely been studied.The objective is to conduct a series of cyclic direct simple shear tests and DEM numerical simulation to investigate the cyclic behaviour of rooted loess.The effects of initial static shear stress and loading frequency on the cyclic resistance of root-soil composites were first investigated.After that,cyclic direct simple shear simulations at constant volume were carried out based on the discrete element method(PFC^(3D))to investigate the effects of root geome-try,mechanical traits and root-soil bond strength on the cyclic strength of rooted loess.It was discovered that the roots could effectively improve the cyclic resistance of loess.The cyclic resistance of the root-soil composite decreases with the increase of the initial shear stress,then increases,and improves with the increase of the frequency.The simulation result show that increases in root elastic modulus and root-soil interfacial bond strength can all enhance the cyclic resistance of root-soil composites,and the maximum cyclic resistance of the root-soil composite was obtained when the initial inclination angle of the root system was 90°.展开更多
Background:Acupuncture has shown potential therapeutic benefits for individuals with simple obesity.However,some researchers argue that some of the effectiveness of acupuncture may be due to the placebo response.Objec...Background:Acupuncture has shown potential therapeutic benefits for individuals with simple obesity.However,some researchers argue that some of the effectiveness of acupuncture may be due to the placebo response.Objective:To understand the placebo response of acupuncture treatment in simple obesity,a systematic review and meta-analysis was designed based on the comparison between sham acupuncture before and after treatment.Search strategy:Eight databases(Pub Med,Web of Science,Cochrane Library,Embase,China National Knowledge Infrastructure,Wanfang Database,China Biology Medicine Database,and Chinese Scientific Journals Database)were searched from inception to August 1,2023.The Me SH search terms comprised obesity and acupuncture.Inclusion criteria:Randomized controlled trials(RCTs)using sham or placebo acupuncture as a control in treating obesity were enrolled.Data extraction and analysis:Two researchers independently extracted data,and the results were crosschecked after completion.Each RCT’s detailed sham/placebo acupuncture treatment protocol was assessed according to the SHam Acupuncture REporting guidelines.The revised Cochrane risk-of-bias tool for randomized trials and the Grading of Recommendations Assessment,Development,and Evaluation(GRADE)system were used to determine the risk of bias and quality of evidence,respectively.Body mass index(BMI)was defined as the primary outcome.Anthropometric parameters and laboratory test parameters related to obesity were defined as secondary outcomes.We used standardized mean difference(SMD)with 95%confidence interval(CI)to calculate treatment effects of outcomes.Results:Fifteen RCTs with a total of 1250 patients were included.The BMI significantly decreased after treatment in the sham acupuncture group compared to baseline(SMD 0.37,95%CI 0.09–0.66;I2=81%,random model;P<0.01).Treatment duration(P=0.02)and other interventions significantly impacted the placebo response rate(P=0.00).Conclusion:The placebo response of sham acupuncture was strong in the RCTs for simple obesity,and the effect sizes differed between various outcomes.The treatment duration and other interventions emerged as potential influencing factors for the placebo response of sham acupuncture.展开更多
Mg alloy often undergoes shear deformation during industrial processing.While its anisotropy and tension-compression asymmetry have been thoroughly studied under uniaxial loading,the understanding for shear loading is...Mg alloy often undergoes shear deformation during industrial processing.While its anisotropy and tension-compression asymmetry have been thoroughly studied under uniaxial loading,the understanding for shear loading is still lacking.This study employed a rolled AZ31B plate with typical basal texture to investigate the shear behaviors.Positive and negative simple shear experiments were performed at different angles in the transverse plane,whereby the visco-plastic self-consistent model was calibrated to reveal the deformation mechanisms and predict the mechanical responses at various orientations.Positive-negative shear asymmetry is present because extension twinning preferentially operates in one shear direction but is suppressed in the opposite direction.Simple shear induces multiple twin variants,thus impedes twin growth and slows the consumption of matrix,as compared to in-plane compression.For slip dominated simple shear,the interaction between loading-induced rigid body rotation and slip-induced crystal rotation produces distinct hardening behaviors,namely orthogonally asymmetric mechanical responses at complementary loading angles,which is largely absent in uniaxial loading.Finally,simulation results verify that positive-negative shear asymmetry appears only when the deviatoric normal stress on the sheet plane is non-zero.Positive-negative shear asymmetry persists except for the conditions of shear plane parallel to sheet plane,or shear direction parallel or perpendicular to rolling direction.展开更多
Background:Radical prostatectomy has long been the treatment of choice for men with clinically significant prostate cancer(PCa)in those with concurrent significant lower urinary tract symptoms(LUTS).For men who meet t...Background:Radical prostatectomy has long been the treatment of choice for men with clinically significant prostate cancer(PCa)in those with concurrent significant lower urinary tract symptoms(LUTS).For men who meet this description with marked prostatomegaly,we present a multi-institutional proof of concept study describing an alternative pathway of robotic simple prostatectomy(RASP)followed by external beam radiation therapy(EBRT)for the treatment of clinically significant prostate cancer.Methods:A retrospective study was performed of 17 patients with PCa who underwent RASP followed by EBRT at two institutions from 2015–2023.Demographic,peri-operative,and post-radiation treatment functional outcomes are reported.Results:No postoperative or post-EBRT complications were reported for any of the 17 patients who underwent RASP followed by EBRT during a median follow-up time of 12 months.The median time from RASP to EBRT was 9 months.Median prostate size was 135 g(IQR 110–165).13(76.5%)patients received a pre-EBRT rectal spacer.Median IPSS score preoperatively improved at 90 days post-RASP(13.5 vs.2.5;IQR 10.8–15.2),and this benefit was sustained post-EBRT with a median IPSS at 3 vs.12 months(4 vs.0;IQR 0–5).There was no statistically significant difference between postoperative IPSS and post-EBRT IPSS at 3(p=0.677)or 12(p=0.627)months.In all 14 patients with localized disease and PSA data,none had recurrence during the study period.Conclusions:A subset of patients with clinically significant prostate cancer have marked prostatomegaly and LUTS.We report an alternative treatment approach for patients unwilling to undergo radical prostatectomy.We found robotic simple prostatectomy followed by definitive radiation to be feasible and safe.展开更多
Weighted exponential distribution W ED(α,λ)with shape parameterαand scale parameterλpossesses some good properties and can be used as a good fit to survival time data compared to other distributions such as gamma,...Weighted exponential distribution W ED(α,λ)with shape parameterαand scale parameterλpossesses some good properties and can be used as a good fit to survival time data compared to other distributions such as gamma,Weibull,or generalized exponential distribution.In this article,we proved the existence and uniqueness of the maximum likelihood estimator(MLE)of the parameters of W ED(α,λ)in simple random sampling(SRS)and provided explicit expressions for the Fisher information number in SRS.Moreover,we also proved the existence and uniqueness of the MLE of the parameters of W ED(α,λ)in ranked set sampling(RSS)and provided explicit expressions for the Fisher information number in RSS.Simulation studies show that these MLEs in RSS can be real competitors for those in SRS.展开更多
Transparent sand is a special material to realize visualization of concealed work in geotechnical engineering. To investigate the dynamic characteristics of transparent sand, a series of undrained cyclic simple shear ...Transparent sand is a special material to realize visualization of concealed work in geotechnical engineering. To investigate the dynamic characteristics of transparent sand, a series of undrained cyclic simple shear tests were conducted on the saturated transparent sand composed of fused quartz and refractive index-matched oil mixture. The results reveal that an increase in the initial shear stress ratio significantly affects the shape of the hysteresis loop, particularly resulting in more pronounced asymmetrical accumulation. Factors such as lower relative density, higher cyclic stress ratios and higher initial shear stress ratio have been shown to accelerate cyclic deformation, cyclic pore water pressure and stiffness degradation. The cyclic liquefaction resistance curves decrease as the initial shear stress ratio increases or as relative density decreases. Booker model and power law function model were applied to predict the pore water pressure for transparent sand. Both models yielded excellent fits for their respective condition, indicating a similar dynamic liquefaction pattern to that of natural sands. Finally, transparent sand displays similar dynamic characteristics in terms of cyclic liquefaction resistance and Kα correction factor. These comparisons indicate that transparent sand can serve as an effective means to mimic many natural sands in dynamic model tests.展开更多
文摘Simple Network Management Protocol (SNMP) is the most widely used network management protocol on TCP/IP based networks. However, the lack of security features, notably authentication and privacy, is its weakness. To rectify this deficiency, a new version of SNMP, known as SNMPv3, is presented. The principal security facilities defined in SNMPv3 which include timeliness mechanism, authentication, privacy and access control are outlined, and a example on how to implement security features in a practical software system is given.
文摘Plant roots are widely known to provide mechanical reinforcement to soils against shearing and further increase slope stability.However,whether roots provide reinforcement to loess cyclic re-sistance and how various factors affect roots reinforcement during seismic loading have rarely been studied.The objective is to conduct a series of cyclic direct simple shear tests and DEM numerical simulation to investigate the cyclic behaviour of rooted loess.The effects of initial static shear stress and loading frequency on the cyclic resistance of root-soil composites were first investigated.After that,cyclic direct simple shear simulations at constant volume were carried out based on the discrete element method(PFC^(3D))to investigate the effects of root geome-try,mechanical traits and root-soil bond strength on the cyclic strength of rooted loess.It was discovered that the roots could effectively improve the cyclic resistance of loess.The cyclic resistance of the root-soil composite decreases with the increase of the initial shear stress,then increases,and improves with the increase of the frequency.The simulation result show that increases in root elastic modulus and root-soil interfacial bond strength can all enhance the cyclic resistance of root-soil composites,and the maximum cyclic resistance of the root-soil composite was obtained when the initial inclination angle of the root system was 90°.
基金supported by grants from the National Natural Science Foundation of China(82405192)the Capital’s Funds for Health Improvement and Research(CFH 2022-2-20213,CFH 2022-1-2021)+1 种基金the project of"Friendship Seed Plan"Talent Project of Beijing Friendship Hospital,Capital Medical University(YYZZ202333)Beijing key project of major disease by Chinese medicine and Western medicine(Fatty liver,No.2023BJSZDYNJBXTGG-017)。
文摘Background:Acupuncture has shown potential therapeutic benefits for individuals with simple obesity.However,some researchers argue that some of the effectiveness of acupuncture may be due to the placebo response.Objective:To understand the placebo response of acupuncture treatment in simple obesity,a systematic review and meta-analysis was designed based on the comparison between sham acupuncture before and after treatment.Search strategy:Eight databases(Pub Med,Web of Science,Cochrane Library,Embase,China National Knowledge Infrastructure,Wanfang Database,China Biology Medicine Database,and Chinese Scientific Journals Database)were searched from inception to August 1,2023.The Me SH search terms comprised obesity and acupuncture.Inclusion criteria:Randomized controlled trials(RCTs)using sham or placebo acupuncture as a control in treating obesity were enrolled.Data extraction and analysis:Two researchers independently extracted data,and the results were crosschecked after completion.Each RCT’s detailed sham/placebo acupuncture treatment protocol was assessed according to the SHam Acupuncture REporting guidelines.The revised Cochrane risk-of-bias tool for randomized trials and the Grading of Recommendations Assessment,Development,and Evaluation(GRADE)system were used to determine the risk of bias and quality of evidence,respectively.Body mass index(BMI)was defined as the primary outcome.Anthropometric parameters and laboratory test parameters related to obesity were defined as secondary outcomes.We used standardized mean difference(SMD)with 95%confidence interval(CI)to calculate treatment effects of outcomes.Results:Fifteen RCTs with a total of 1250 patients were included.The BMI significantly decreased after treatment in the sham acupuncture group compared to baseline(SMD 0.37,95%CI 0.09–0.66;I2=81%,random model;P<0.01).Treatment duration(P=0.02)and other interventions significantly impacted the placebo response rate(P=0.00).Conclusion:The placebo response of sham acupuncture was strong in the RCTs for simple obesity,and the effect sizes differed between various outcomes.The treatment duration and other interventions emerged as potential influencing factors for the placebo response of sham acupuncture.
基金supports of the National Key Research and Development Program of China(Grant No.2023YFB3710900)the National Natural Science Foundation of China(Grant Nos.52071211 and 52071208)。
文摘Mg alloy often undergoes shear deformation during industrial processing.While its anisotropy and tension-compression asymmetry have been thoroughly studied under uniaxial loading,the understanding for shear loading is still lacking.This study employed a rolled AZ31B plate with typical basal texture to investigate the shear behaviors.Positive and negative simple shear experiments were performed at different angles in the transverse plane,whereby the visco-plastic self-consistent model was calibrated to reveal the deformation mechanisms and predict the mechanical responses at various orientations.Positive-negative shear asymmetry is present because extension twinning preferentially operates in one shear direction but is suppressed in the opposite direction.Simple shear induces multiple twin variants,thus impedes twin growth and slows the consumption of matrix,as compared to in-plane compression.For slip dominated simple shear,the interaction between loading-induced rigid body rotation and slip-induced crystal rotation produces distinct hardening behaviors,namely orthogonally asymmetric mechanical responses at complementary loading angles,which is largely absent in uniaxial loading.Finally,simulation results verify that positive-negative shear asymmetry appears only when the deviatoric normal stress on the sheet plane is non-zero.Positive-negative shear asymmetry persists except for the conditions of shear plane parallel to sheet plane,or shear direction parallel or perpendicular to rolling direction.
文摘Background:Radical prostatectomy has long been the treatment of choice for men with clinically significant prostate cancer(PCa)in those with concurrent significant lower urinary tract symptoms(LUTS).For men who meet this description with marked prostatomegaly,we present a multi-institutional proof of concept study describing an alternative pathway of robotic simple prostatectomy(RASP)followed by external beam radiation therapy(EBRT)for the treatment of clinically significant prostate cancer.Methods:A retrospective study was performed of 17 patients with PCa who underwent RASP followed by EBRT at two institutions from 2015–2023.Demographic,peri-operative,and post-radiation treatment functional outcomes are reported.Results:No postoperative or post-EBRT complications were reported for any of the 17 patients who underwent RASP followed by EBRT during a median follow-up time of 12 months.The median time from RASP to EBRT was 9 months.Median prostate size was 135 g(IQR 110–165).13(76.5%)patients received a pre-EBRT rectal spacer.Median IPSS score preoperatively improved at 90 days post-RASP(13.5 vs.2.5;IQR 10.8–15.2),and this benefit was sustained post-EBRT with a median IPSS at 3 vs.12 months(4 vs.0;IQR 0–5).There was no statistically significant difference between postoperative IPSS and post-EBRT IPSS at 3(p=0.677)or 12(p=0.627)months.In all 14 patients with localized disease and PSA data,none had recurrence during the study period.Conclusions:A subset of patients with clinically significant prostate cancer have marked prostatomegaly and LUTS.We report an alternative treatment approach for patients unwilling to undergo radical prostatectomy.We found robotic simple prostatectomy followed by definitive radiation to be feasible and safe.
基金Supported by the National Science Foundation of China(11901236,12261036)Scientific Research Fund of Hunan Provincial Education Department(21A0328)+2 种基金Provincial Natural Science Foundation of Hunan(2022JJ30469)Young Core Teacher Foundation of Hunan Province([2020]43)Provincial Postgraduate Innovation Foundation of Hunan(CX20221113)。
文摘Weighted exponential distribution W ED(α,λ)with shape parameterαand scale parameterλpossesses some good properties and can be used as a good fit to survival time data compared to other distributions such as gamma,Weibull,or generalized exponential distribution.In this article,we proved the existence and uniqueness of the maximum likelihood estimator(MLE)of the parameters of W ED(α,λ)in simple random sampling(SRS)and provided explicit expressions for the Fisher information number in SRS.Moreover,we also proved the existence and uniqueness of the MLE of the parameters of W ED(α,λ)in ranked set sampling(RSS)and provided explicit expressions for the Fisher information number in RSS.Simulation studies show that these MLEs in RSS can be real competitors for those in SRS.
基金Project(U2268213) supported by the National Natural Science Foundation of ChinaProject(2024YFHZ0121) supported by the Sichuan Science and Technology Program,China。
文摘Transparent sand is a special material to realize visualization of concealed work in geotechnical engineering. To investigate the dynamic characteristics of transparent sand, a series of undrained cyclic simple shear tests were conducted on the saturated transparent sand composed of fused quartz and refractive index-matched oil mixture. The results reveal that an increase in the initial shear stress ratio significantly affects the shape of the hysteresis loop, particularly resulting in more pronounced asymmetrical accumulation. Factors such as lower relative density, higher cyclic stress ratios and higher initial shear stress ratio have been shown to accelerate cyclic deformation, cyclic pore water pressure and stiffness degradation. The cyclic liquefaction resistance curves decrease as the initial shear stress ratio increases or as relative density decreases. Booker model and power law function model were applied to predict the pore water pressure for transparent sand. Both models yielded excellent fits for their respective condition, indicating a similar dynamic liquefaction pattern to that of natural sands. Finally, transparent sand displays similar dynamic characteristics in terms of cyclic liquefaction resistance and Kα correction factor. These comparisons indicate that transparent sand can serve as an effective means to mimic many natural sands in dynamic model tests.