This paper aims to evaluate the stochastic response of steel columns subjected to blast loads using the modified single degree of freedom(MSDOF)method,which assessed towards the conventional single degree of freedom(S...This paper aims to evaluate the stochastic response of steel columns subjected to blast loads using the modified single degree of freedom(MSDOF)method,which assessed towards the conventional single degree of freedom(SDOF)and the experimentally validated Finite Element(FE)methods(LSDYNA).For this purpose,special atten-tion is given to calculating the response of H-shaped steel columns under blast.The damage amount is determined based on the support rotation criterion,which is expressed as a function of their maximum lateral mid-span dis-placement.To account for uncertainties in input parameters and obtain the failure probability,the Monte Carlo simulation(MCS)method is employed,complemented by the Latin Hypercube Sampling(LHS)method to reduce the number of simulations.A parametric analysis is hence performed to examine the effect of several input pa-rameters(including both deterministic and probabilistic parameters)on the probability of column damage as a function of support rotation.First,the MSDOF method confirms its higher accuracy in estimating the probability of column damage due to blast,compared to the conventional SDOF.The collected results also show that un-certainties of several input parameters have significant effects on the column behavior.In particular,geometric parameters(including cross-sectional characteristics,boundary conditions and column length)have major effect on the corresponding column response,in the same way of input blast load parameters and material properties.展开更多
Earthquake may cause severe damage to all kinds of bridge such as the falling down of the girder; therefore,effective measures should be employed to control the seismic displacement. In this paper,the method of compre...Earthquake may cause severe damage to all kinds of bridge such as the falling down of the girder; therefore,effective measures should be employed to control the seismic displacement. In this paper,the method of comprehensive optimal control,com-bined with analytic hierarchy process,is employed to investigate the seismic response control of the Nanjing Jiangxinzhou Bridge,which is a single-tower self-anchored suspension bridge （SSSB）. Also,3-dimensional nonlinear seismic response analyses are con-ducted. Three types of practical connection measures for seismic response control of SSSB are investigated,and the optimal pa-rameters of the connection devices are achieved by this method. Results show that both the elastic connection devices and the damp-ers with rational parameters can reduce the seismic displacement of the bridge effectively,but the elastic connection devices will in-crease the seismic force of the tower. When all factors are consid-ered,the optimal measure is by using the elastic connection devices and the dampers together. These results can provide references for seismic response control of SSSBs.展开更多
Organic–inorganic single-crystalline perovskites have attracted significant attentions due to their exceptional progress in intrinsic properties＇ investigation and applications in photovoltaics and optoelectronics. ...Organic–inorganic single-crystalline perovskites have attracted significant attentions due to their exceptional progress in intrinsic properties＇ investigation and applications in photovoltaics and optoelectronics. In this study, the large perovskite CH3NH3PbI3 single crystal with the largest length of 80 mm was prepared through the method of inverse-temperature crystallization. Meanwhile, the mass production of integrate photodetectors have been fabricated on the single-crystalline wafer and the photoresponse performances were investigated. The results show that the single-crystalline photodetectors have broad spectrum response to 900 nm, rapid response speed（〈40 μs） and excellent stability. These findings are of great importance for future promising perovskite single crystalline for integrated photoelectronic application.展开更多
Background: The present study performed a meta-analysis to comprehensively analyze existing randomized controlled trials (RCT) involving the use of double-lumen needle in patients with poor ovarian response to explore...Background: The present study performed a meta-analysis to comprehensively analyze existing randomized controlled trials (RCT) involving the use of double-lumen needle in patients with poor ovarian response to explore whether double-lumen needle was good for specific patients. Methods: The PubMed, EMBASE, Cochrane Library databases and two randomized controlled trials registration centers were thoroughly searched until April 2017. The clinical outcomes of IVF/ICSI cycles were compared between two groups with double-lumen needle and single-lumen needle. Results: Four RCT studies were included in this present meta-analysis. The oocytes yield was similar in two groups (OR 0.88, 95%CI 0.66 - 1.16;I2 = 4%). The procedure time with double-lumen needle was significantly longer than that with single-lumen needle (IV = 1.98, 95%CI 0.95 - 3.00;I2 = 86%). The fertilization rate with double-lumen needle was lower than that with single-lumen needle (OR 0.66, 95%CI 0.44 - 0.97;I2 = 0%). There was no significant difference of live birth rate in two groups (OR 0.76, 95%CI 0.32 - 1.76;I2 = 41%). Conclusion: Double-lumen needle could not benefit patients with a POR in terms of the number of oocytes retrieved, oocyte recovery rate, normal fertilization rate, clinical pregnancy rate, and live birth rate, compared with single-lumen needle.展开更多
The subharmonic response of a single-degree-of-freedom linear vibroimpact oscillator with a one-sided barrier to the narrow-band random excitation is investigated.The analysis is based on a special Zhuravlev transform...The subharmonic response of a single-degree-of-freedom linear vibroimpact oscillator with a one-sided barrier to the narrow-band random excitation is investigated.The analysis is based on a special Zhuravlev transformation,which reduces the system to the one without impacts or velocity jumps,and thereby permits the applications of asymptotic averaging over the period for slowly varying the inphase and quadrature responses.The averaged stochastic equations are exactly solved by the method of moments for the mean square response amplitude for the case of zero offset.A perturbation-based moment closure scheme is proposed for the case of nonzero offset.The effects of damping,detuning,and bandwidth and magnitudes of the random excitations are analyzed.The theoretical analyses are verified by the numerical results.The theoretical analyses and numerical simulations show that the peak amplitudes can be strongly reduced at the large detunings.展开更多
The geomagnetic night-time values were used to estimate the electromagnetic response function Q1 for half-year period. If the spatial structure of the source field can be described by the approximation, one can estim...The geomagnetic night-time values were used to estimate the electromagnetic response function Q1 for half-year period. If the spatial structure of the source field can be described by the approximation, one can estimate the Q1 value using the single-station Z/H method. This technique enables us to carry out regional deep gcomagnetic sounding by the method. The data used for analyses are geomagnetic night-time values for about, typically, 26 years from 5 good-quality stations and for several years from 34 stations distributed over the globe. The results indicate that the night-time values yield more reliable response estimates for half-year period compared to the usual estimates obtained from daily means. It implies that the approximation for the night-time fields holds good for the half-year period, but the daily means are not suitable for estimating the response function of the semi-annual variations by using the single-station method. Source field analyses for daily means data and night-time means data have also been carried out in this paper.展开更多
Organic semiconductor materials have shown unique advantages in the development of optoelectronic devices due to their ease of preparation,low cost,lightweight,and flexibility.In this work,we explored the application ...Organic semiconductor materials have shown unique advantages in the development of optoelectronic devices due to their ease of preparation,low cost,lightweight,and flexibility.In this work,we explored the application of the organic semiconductor Y6-1O single crystal in photodetection devices.Firstly,Y6-1O single crystal material was prepared on a silicon substrate using solution droplet casting method.The optical properties of Y6-1O material were characterized by polarized optical microscopy,fluorescence spectroscopy,etc.,confirming its highly single crystalline performance and emission properties in the near-infrared region.Phototransistors based on Y6-1O materials with different thicknesses were then fabricated and tested.It was found that the devices exhibited good visible to near-infrared photoresponse,with the maximum photoresponse in the near-infrared region at 785 nm.The photocurrent on/off ratio reaches 10^(2),and photoresponsivity reaches 16 mA/W.It was also found that the spectral response of the device could be regulated by gate voltage as well as the material thickness,providing important conditions for optimizing the performance of near-infrared photodetectors.This study not only demonstrates the excellent performance of organic phototransistors based on Y6-1O single crystal material in near-infrared detection but also provides new ideas and directions for the future development of infrared detectors.展开更多
BACKGROUND Nasopharyngeal carcinoma(NPC),exhibiting high incidence in southern China,is linked to genetic and environmental factors.Vitamin D metabolism,involving transport[group-specific component(GC)protein]and acti...BACKGROUND Nasopharyngeal carcinoma(NPC),exhibiting high incidence in southern China,is linked to genetic and environmental factors.Vitamin D metabolism,involving transport[group-specific component(GC)protein]and activation[25-hydroxylase(CYP2R1)enzyme],may influence NPC susceptibility and radiotherapy response.Polymorphisms in GC and CYP2R1 genes affect protein function and serum 25-hydroxyvitamin D[25(OH)D]levels,and are implicated in other cancers.However,their role in NPC-particularly in high-risk Han Chinese populations-and interaction with vitamin D status remains unclear.This case control study(360 NPC patients,550 controls)investigates these relationships to inform prevention and personalized therapy.AIM To investigate the association between vitamin D binding protein(GC)and CYP2R1 gene polymorphisms with susceptibility to NPC and radiotherapy response.METHODS A case control study design was adopted,and 360 patients with NPC and 550 healthy controls were included.TaqMan method was used to perform genotyping on GC gene loci rs4588,rs7041,and CYP2R1 gene loci rs10741657,rs12794714.Serum 25(OH)D levels were detected,and the relationship between gene polymorphisms and NPC risk and radiotherapy response was analyzed.RESULTS The GC gene rs4588 TT genotype was significantly associated with the risk of NPC in both the codominant model[odds ratio(OR)=1.68,95%CI:1.15-2.45,P=0.007]and the recessive model(OR=1.56,95%CI:1.02-2.38,P=0.039).The association between the rs4588 TT genotype and the risk of NPC was more significant in the male subgroup(OR=1.87,95%CI:1.11-3.15,P=0.019)and the squamous cell carcinoma subgroup(OR=1.89,95%CI:1.19-3.00,P=0.007).The serum 25(OH)D level of the rs7041 AA genotype carriers was significantly lower than that of the CC genotype(P<0.001).The CYP2R1 gene rs10741657 AA genotype was associated with higher serum 25(OH)D levels(P=0.003).The rs12794714 AA genotype was associated with radiotherapy resistance(OR=1.76,95%CI:1.18-2.63,P=0.005).Stratified analysis showed that the association between rs4588 and rs12794714 was significant only in the subgroup with higher 25(OH)D levels.CONCLUSION GC and CYP2R1 genes polymorphisms are associated with NPC susceptibility and radiotherapy response,and this association may be affected by serum 25(OH)D levels.This study provides a new idea for the prevention and individualized treatment in NPC.展开更多
Chiral topological semimetals hosting multifold fermions and exotic surface states represent a frontier in topological materials research. Among them, noncentrosymmetric cubic B20 compounds—notably transitionmetal si...Chiral topological semimetals hosting multifold fermions and exotic surface states represent a frontier in topological materials research. Among them, noncentrosymmetric cubic B20 compounds—notably transitionmetal silicides and germanides—offer a unique platform for realizing symmetry-protected topological phases and unconventional optoelectronic responses. Here, we report the physical properties of Rh Ge and Co Ge single crystals with B20 structure in detail. Transport measurements revea metallic behavior with characteristic Fermi-liquid scaling at low temperatures, while magnetization results confirm paramagnetism in both compounds. In addition,both materials exhibit low carrier concentrations with small electronic specific heat coefficients, indicating their semimetal feature with weak electronic correlations. Such high-quality Co Ge and Rh Ge single crystals provide a material platform to explore the evolution of multifold fermions and the instability of helicoid-arc surface states with spin–orbit coupling and surface environment in B20 material systems.展开更多
Herein,we report self-assembly of tadpole-like single chain polymeric nanoparticles(TPPs)and the ultrasonic response of the resultant superparticles.The TPPs are with an intramolecularly crosslinked poly(2-(methacrylo...Herein,we report self-assembly of tadpole-like single chain polymeric nanoparticles(TPPs)and the ultrasonic response of the resultant superparticles.The TPPs are with an intramolecularly crosslinked poly(2-(methacryloyloxy)ethyl pent-4-ynoate)-rpoly(hydroxyethyl methacrylate)(PMAEP-r-PHEMA)chain as the"head"and a poly(2-(dimethylamino))ethyl methacrylate(PDMAEMA)linear chain as the"tail",and are pre-pared simply and emciently by Glaser-coupling of the pendant alkynes in the PMAEP-r-PHEMA block in the common solvent methanol.The formation of the TPPs was confirmed by gel permeation chromatograph,nuclear magnetic resonance spectroscopy,dynamic light scattering,static dynamic scattering,and transmission electron microscopy.In aqueous solution,the amphiphilic TPPs could self-assemble into regular superparticles,driven by aggregation of the hydrophobic"heads".Since in the structure there is no chain entanglement and the embedding of PDMAEMA chains disturb close-packing of the"heads",the superpartieles are responsive to a low-energy ultrasonic vibration,as evidenced by greatly enhanced release of the functional molecules from the superparticles by treatment of a low-energy ultrasound.Therefore,the superparticles should be very promising in the use as the drug carriers that can be manipulated from a long distance,considering that ultrasonic energy can be focused at a small area in a relatively long distance from the ultrasound-radiating source.展开更多
A numerical model for steady state analysis and analytical expressions for the AM and FM modulation responses of DFB lasers are presented.The small signal modulation responses of 3 phase shift(PS) DFB is investigate...A numerical model for steady state analysis and analytical expressions for the AM and FM modulation responses of DFB lasers are presented.The small signal modulation responses of 3 phase shift(PS) DFB is investigated for the first time.A new method(Vector Newton method) to obtain multiple longitudinal mode of DFB lasers is used.It is demonstrated that this method is suitable for obtaining multiple solution of high nonlinear equations.Longitudinal photon density distribution and multiple longitudinal mode of 3PS DFB and simple DFB lasers are analyzed.The results show that modulation response characteristics of 3PS DFB laser is as good as that of DFB,and PS can weaken the longitudinal spatial hole burning (LHSB) effect and is in favor of single longitudinal mode operating of lasers.展开更多
Single fiber pull-out testing was conducted to study the origin of the functional responses to loading of carbon fiber reinforced cement-based composites. The variation of electrical resistance with the bonding force ...Single fiber pull-out testing was conducted to study the origin of the functional responses to loading of carbon fiber reinforced cement-based composites. The variation of electrical resistance with the bonding force on the fiber-matrix interface was measured. Single fiber electromechanical testing was also conducted by measuring the electrical resistance under static tension. Comparison of the results shows that the resistance increasing during single fiber pull-out is mainly due to the changes at the interface. The conduction mechanism of the composite can be explained by the tunneling model. The interfacial stress causes the deformation of interfacial structure and the interfacial debonding, which have influences on the tunneling effect and result in the change of resistance.展开更多
To relieve dust pollution in open cut coal mines and reduce the hazards of coal dust pollution to the environment and workers we optimized the synthesis of a dust suppressant by graft copolymerization of environmental...To relieve dust pollution in open cut coal mines and reduce the hazards of coal dust pollution to the environment and workers we optimized the synthesis of a dust suppressant by graft copolymerization of environmentally friendly soy protein isolate with methyl methacrylate.This dust suppressant could effectively control dust pollution in open cut coal mines. The optimized conditions for graft copolymerization in this case were determined by a response surface experiment designed with Design-Expert 10 software. Characterization by scanning electron microscopy showed a significant morphology change of the dust suppressant and the generation of a rigid and dense layer on its surface after interacting with coal dust.The layer exhibited good bonding and dust suppression performance. The analysis with Fourier-transform infrared spectroscopy revealed the appearance of new absorption peaks near 1300, 1072, and 1631 cm, demonstrating effective graft copolymerization. The proposed dust suppressant exhibited excellent wind erosion resistance, with a resistance that exceeded 90% at a wind speed of 6.5 m/sec. The successful graft copolymerization and effective bonding and curing of the dust suppressant on coal dust were experimentally verified.This is of great significance to the control of coal dust pollution.展开更多
Coupled effects on a single point mooring(SPM) system subjected to the combined action of wind,waves and current are studied in this paper. Due to the complicatedness of the sea state and the huge size of the vessel,p...Coupled effects on a single point mooring(SPM) system subjected to the combined action of wind,waves and current are studied in this paper. Due to the complicatedness of the sea state and the huge size of the vessel,physical experimental study is both time consuming and uneconomical,whereas the numerical study is cost-effective and DNV software provides powerful SESAM software in solving the issues. This paper focuses on the modeling process of the SPM system,catenary equilibrium calculation,static analysis of the vessel in three different scenarios,and dynamic response simulation of the SPM system under environmental excitations. The three scenarios in study are as follows:the SPM is under the combined function of(a) wind,waves and current,(b) wind and waves,(c) current and waves. They are so set that one can compare the contributions of different types of loads in both static and dynamic studies. Numerical study shows that wind and current are the two major factors contributing to the mooring line tension,and surge and sway are the two dominant motions of the moored vessel subjected to environmental excitations.展开更多
A two-dimensional （2D） finite element analysis was carried out to assess the time-dependent behavior of single vertical pile embedded in elasto-plastic soil. The finite element analyses were carried out using the li...A two-dimensional （2D） finite element analysis was carried out to assess the time-dependent behavior of single vertical pile embedded in elasto-plastic soil. The finite element analyses were carried out using the linear elastic model for the structure of the pile, while the Mohr-Coulomb model was used for representing the soil behavior surrounding the pile. The study includes cohesionless and cohesive soil to assess the lateral response of pile in the two types of soil. The whole geoteehnical model is suitable for problem of piles to determine the design quantities such as lateral deformation, lateral soil stress and its variation with time. The model is verified based on the results of published cases and there is good comparison between the results of published ease and the present simulation model. It is found that, the pile in cohesionless soil has more resistance in the rapid loading and less one in the long term loading. On the other hand, the pile in cohesive soil shows opposite behavior.展开更多
To investigate genetic factors that might help define which Crohn’s disease(CD)patients are likely to benefit from anti-tumor necrosis factor(TNF)therapy.METHODSThis was a prospective cohort study.Patients were recru...To investigate genetic factors that might help define which Crohn’s disease(CD)patients are likely to benefit from anti-tumor necrosis factor(TNF)therapy.METHODSThis was a prospective cohort study.Patients were recruited from a university digestive disease practice database.We included CD patients who received anti-TNF therapy,had available medical records(with information on treatment duration and efficacy)and who consented to participation.Patients with allergic reactions were excluded.Patients were grouped as ever-responders or non-responders.Genomic DNA was extracted from peripheral blood,and 7 single nucleotide polymorphisms(SNPs)were assessed.The main outcome measure(following exposure to the drug)was response to therapy.The patient genotypes were assessed as the predictors of outcome.Possible confounders and effect modifiers included age,gender,race,and socioeconomic status disease,as well as disease characteristics(such as Montreal criteria).RESULTS121 patients were included.Twenty-one were non-responders,and 100 were ever-responders.Fas ligand SNP(rs763110)genotype frequencies,TNF gene-308 SNP(rs1800629)genotype frequencies,and their combination,were significantly different between groups on multivariable analysis controlling for Montreal disease behavior and perianal disease.The odds of a patient with a Fas ligand CC genotype being a non-responder were four-fold higher as compared to a TC or TT genotype(P=0.009,OR=4.30,95%CI:1.45-12.80).The presence of the A(minor)TNF gene-308 allele correlated with three-fold higher odds of being a non-responder(P=0.049,OR=2.88,95%CI:1.01-8.22).Patients with the combination of the Fas ligand CC genotype and the TNF-308 A allele had nearly five-fold higher odds of being a non-responder(P=0.015,OR=4.76,95%CI:1.35-16.77).No difference was seen for the remaining SNPs.CONCLUSIONThe Fas-ligand SNP and TNF gene-308 SNP are associated with anti-TNF treatment response in CD and may help select patients likely to benefit from therapy.展开更多
Study on the dynamic response, and especially the nonlinear dynamic response of stiffened plates is complicated by their discontinuity and inhomogeneity. The finite element method (FEM) and the finite strip method are...Study on the dynamic response, and especially the nonlinear dynamic response of stiffened plates is complicated by their discontinuity and inhomogeneity. The finite element method (FEM) and the finite strip method are usually adopted in their analysis. Although many useful conclusions have been obtained, the computational cost is enormous. Based on some assumptions, the dynamic plastic response of clamped stiffened plates with large deflections was theoretically investigated herein by a singly symmetric beam model. Firstly, the deflection conditions that a plastic string must satisfy were obtained by the linearized moment-axial force interaction curve for singly symmetric cross sections and the associated plastic flow rule. Secondly, the possible motion mechanisms of the beam under different load intensity were analysed in detail. For structures with plastic deformations, a simplified method was then given that the arbitrary impact load can be replaced equivalently by a rectangular pulse. Finally, to confirm the validity of the proposed method, the dynamic plastic response of a one-way stiffened plate with four fully clamped edges was calculated. The theoretical results were in good agreement with those of FEM. It indicates that the present calculation model is easy and feasible, and the equivalent substitution of load almost has no influence on the final deflection.展开更多
[Objectives]This study was conducted to screen best process parameters for making Foshou yam and honey can.[Methods]The Foshou yam produced from Wuxue was used as a raw material to prepare Foshou yam and honey nutriti...[Objectives]This study was conducted to screen best process parameters for making Foshou yam and honey can.[Methods]The Foshou yam produced from Wuxue was used as a raw material to prepare Foshou yam and honey nutritional can by combining Foshou yam with honey through screening,pre-cooking,filling,exhausting,cooling and other technical processes.The optimum technology parameter of Foshou yam and honey nutritional can was studied through single factor tests and response surface optimization.[Results]The optimum technical parameters of Foshou yam and honey nutritional can were citric acid concentration 0.1%,amount of edible salt 0.1%,cooking time 14 min and honey concentration 26%.Under these conditions,the final sensory score was 90.20.The prepared can was not only rich in nutrition,but also had good flavor and taste.[Conclusions]This study provides reference for the development and utilization of Foshou yam and the research and development of functional food.展开更多
In general, the seismic response analysis in earthquake engineering assumes that the vibration parameters of the target and the contact surface of the external media are identical,i. e., single point input. However, e...In general, the seismic response analysis in earthquake engineering assumes that the vibration parameters of the target and the contact surface of the external media are identical,i. e., single point input. However, earthquake energy has an attenuation phenomenon in wave propagation,so a wide range of soil slopes and the external medium contact surface of different input points on motion are not identical. If we consider single point input only, it may not correspond with reality, so it is necessary to carry out research on multi-point input methods. Based on the 2-D slope model,single-point input and multi-point input are performed respectively to analyze and compare their similarities and differences in the perspectives of the characteristics of seismic response of soil layer and plastic zone distribution to provide a reference for the seismic design of slopes. The results show that in the perspective of soil seismic response analysis,the peak acceleration output and peak velocity output under multi-point input are greater than the peak values under single point input at the same monitoring point,the peak appearing time is also earlier than that of the single point input; in terms of the plastic zone distribution,the multi-point effect is manifested as the presence of more obvious tensile shear failures; in the perspective of safety coefficient,the safety coefficient under each multi-point input is smaller than that of single point input,a difference of about 7 % or so. In summary,multi-point input is more reasonable and practical than single point input,so multi-point input should be considered in seismic design.展开更多
An adaptive current compensation control for a single-sided linear induction motor(SLIM) with nonlinear disturbance observer was developed. First, to maintain t-axis secondary component flux constant with consideratio...An adaptive current compensation control for a single-sided linear induction motor(SLIM) with nonlinear disturbance observer was developed. First, to maintain t-axis secondary component flux constant with consideration of the specially dynamic eddy-effect(DEE) of the SLIM, a instantaneously tracing compensation of m-axis current component was analyzed. Second,adaptive current compensation based on Taylor-discretization algorithm was proposed. Third, an effective kind of nonlinear disturbance observer(NDOB) was employed to estimate and compensate the undesired load vibrations, then the robustness of the control system could be guaranteed. Experimental verification of the feasibility of the proposed method for an SLIM control system was performed, and it showed that the proposed adaptive compensation scheme with NDOB could significantly promote speed dynamical response and minimize speed ripple under the conditions of external load coupled vibrations and unavoidable feedback control variables measured errors, i.e., current and speed.展开更多
文摘This paper aims to evaluate the stochastic response of steel columns subjected to blast loads using the modified single degree of freedom(MSDOF)method,which assessed towards the conventional single degree of freedom(SDOF)and the experimentally validated Finite Element(FE)methods(LSDYNA).For this purpose,special atten-tion is given to calculating the response of H-shaped steel columns under blast.The damage amount is determined based on the support rotation criterion,which is expressed as a function of their maximum lateral mid-span dis-placement.To account for uncertainties in input parameters and obtain the failure probability,the Monte Carlo simulation(MCS)method is employed,complemented by the Latin Hypercube Sampling(LHS)method to reduce the number of simulations.A parametric analysis is hence performed to examine the effect of several input pa-rameters(including both deterministic and probabilistic parameters)on the probability of column damage as a function of support rotation.First,the MSDOF method confirms its higher accuracy in estimating the probability of column damage due to blast,compared to the conventional SDOF.The collected results also show that un-certainties of several input parameters have significant effects on the column behavior.In particular,geometric parameters(including cross-sectional characteristics,boundary conditions and column length)have major effect on the corresponding column response,in the same way of input blast load parameters and material properties.
基金Supported by the National Natural Science Foundation of China for Distinguished Young Scientists (50725828)the National Natural Science Foundation of China (50908046)the Specialized Research Fund for the Doctoral Program of Higher Education (200802861012)
文摘Earthquake may cause severe damage to all kinds of bridge such as the falling down of the girder; therefore,effective measures should be employed to control the seismic displacement. In this paper,the method of comprehensive optimal control,com-bined with analytic hierarchy process,is employed to investigate the seismic response control of the Nanjing Jiangxinzhou Bridge,which is a single-tower self-anchored suspension bridge （SSSB）. Also,3-dimensional nonlinear seismic response analyses are con-ducted. Three types of practical connection measures for seismic response control of SSSB are investigated,and the optimal pa-rameters of the connection devices are achieved by this method. Results show that both the elastic connection devices and the damp-ers with rational parameters can reduce the seismic displacement of the bridge effectively,but the elastic connection devices will in-crease the seismic force of the tower. When all factors are consid-ered,the optimal measure is by using the elastic connection devices and the dampers together. These results can provide references for seismic response control of SSSBs.
基金support from the National Key Research and Development Program of China(no.2016YFA0202403)National Natural Science Foundation of China(nos.61604091/61674098)+3 种基金the 111 Project(B14041)the National University Research Fund(grant nos.GK261001009,GK201603107)Changjiang Scholar and Innovative Research Team(IRT_14R33)the Chinese National 1000-talent-plan program(1110010341)
文摘Organic–inorganic single-crystalline perovskites have attracted significant attentions due to their exceptional progress in intrinsic properties＇ investigation and applications in photovoltaics and optoelectronics. In this study, the large perovskite CH3NH3PbI3 single crystal with the largest length of 80 mm was prepared through the method of inverse-temperature crystallization. Meanwhile, the mass production of integrate photodetectors have been fabricated on the single-crystalline wafer and the photoresponse performances were investigated. The results show that the single-crystalline photodetectors have broad spectrum response to 900 nm, rapid response speed（〈40 μs） and excellent stability. These findings are of great importance for future promising perovskite single crystalline for integrated photoelectronic application.
文摘Background: The present study performed a meta-analysis to comprehensively analyze existing randomized controlled trials (RCT) involving the use of double-lumen needle in patients with poor ovarian response to explore whether double-lumen needle was good for specific patients. Methods: The PubMed, EMBASE, Cochrane Library databases and two randomized controlled trials registration centers were thoroughly searched until April 2017. The clinical outcomes of IVF/ICSI cycles were compared between two groups with double-lumen needle and single-lumen needle. Results: Four RCT studies were included in this present meta-analysis. The oocytes yield was similar in two groups (OR 0.88, 95%CI 0.66 - 1.16;I2 = 4%). The procedure time with double-lumen needle was significantly longer than that with single-lumen needle (IV = 1.98, 95%CI 0.95 - 3.00;I2 = 86%). The fertilization rate with double-lumen needle was lower than that with single-lumen needle (OR 0.66, 95%CI 0.44 - 0.97;I2 = 0%). There was no significant difference of live birth rate in two groups (OR 0.76, 95%CI 0.32 - 1.76;I2 = 41%). Conclusion: Double-lumen needle could not benefit patients with a POR in terms of the number of oocytes retrieved, oocyte recovery rate, normal fertilization rate, clinical pregnancy rate, and live birth rate, compared with single-lumen needle.
基金supported by the National Natural Science Foundation of China (Nos. 10772046 and 50978058)the Natural Science Foundation of Guangdong Province of China (Nos. 7010407 and 05300566)
文摘The subharmonic response of a single-degree-of-freedom linear vibroimpact oscillator with a one-sided barrier to the narrow-band random excitation is investigated.The analysis is based on a special Zhuravlev transformation,which reduces the system to the one without impacts or velocity jumps,and thereby permits the applications of asymptotic averaging over the period for slowly varying the inphase and quadrature responses.The averaged stochastic equations are exactly solved by the method of moments for the mean square response amplitude for the case of zero offset.A perturbation-based moment closure scheme is proposed for the case of nonzero offset.The effects of damping,detuning,and bandwidth and magnitudes of the random excitations are analyzed.The theoretical analyses are verified by the numerical results.The theoretical analyses and numerical simulations show that the peak amplitudes can be strongly reduced at the large detunings.
文摘The geomagnetic night-time values were used to estimate the electromagnetic response function Q1 for half-year period. If the spatial structure of the source field can be described by the approximation, one can estimate the Q1 value using the single-station Z/H method. This technique enables us to carry out regional deep gcomagnetic sounding by the method. The data used for analyses are geomagnetic night-time values for about, typically, 26 years from 5 good-quality stations and for several years from 34 stations distributed over the globe. The results indicate that the night-time values yield more reliable response estimates for half-year period compared to the usual estimates obtained from daily means. It implies that the approximation for the night-time fields holds good for the half-year period, but the daily means are not suitable for estimating the response function of the semi-annual variations by using the single-station method. Source field analyses for daily means data and night-time means data have also been carried out in this paper.
基金Supported by the National Key Research and Development Program of China(2021YFB2012601)National Natural Science Foundation of China(12204109)+1 种基金Science and Technology Innovation Plan of Shanghai Science and Technology Commission(21JC1400200)Higher Education Indus⁃try Support Program of Gansu Province(2022CYZC-06)。
文摘Organic semiconductor materials have shown unique advantages in the development of optoelectronic devices due to their ease of preparation,low cost,lightweight,and flexibility.In this work,we explored the application of the organic semiconductor Y6-1O single crystal in photodetection devices.Firstly,Y6-1O single crystal material was prepared on a silicon substrate using solution droplet casting method.The optical properties of Y6-1O material were characterized by polarized optical microscopy,fluorescence spectroscopy,etc.,confirming its highly single crystalline performance and emission properties in the near-infrared region.Phototransistors based on Y6-1O materials with different thicknesses were then fabricated and tested.It was found that the devices exhibited good visible to near-infrared photoresponse,with the maximum photoresponse in the near-infrared region at 785 nm.The photocurrent on/off ratio reaches 10^(2),and photoresponsivity reaches 16 mA/W.It was also found that the spectral response of the device could be regulated by gate voltage as well as the material thickness,providing important conditions for optimizing the performance of near-infrared photodetectors.This study not only demonstrates the excellent performance of organic phototransistors based on Y6-1O single crystal material in near-infrared detection but also provides new ideas and directions for the future development of infrared detectors.
文摘BACKGROUND Nasopharyngeal carcinoma(NPC),exhibiting high incidence in southern China,is linked to genetic and environmental factors.Vitamin D metabolism,involving transport[group-specific component(GC)protein]and activation[25-hydroxylase(CYP2R1)enzyme],may influence NPC susceptibility and radiotherapy response.Polymorphisms in GC and CYP2R1 genes affect protein function and serum 25-hydroxyvitamin D[25(OH)D]levels,and are implicated in other cancers.However,their role in NPC-particularly in high-risk Han Chinese populations-and interaction with vitamin D status remains unclear.This case control study(360 NPC patients,550 controls)investigates these relationships to inform prevention and personalized therapy.AIM To investigate the association between vitamin D binding protein(GC)and CYP2R1 gene polymorphisms with susceptibility to NPC and radiotherapy response.METHODS A case control study design was adopted,and 360 patients with NPC and 550 healthy controls were included.TaqMan method was used to perform genotyping on GC gene loci rs4588,rs7041,and CYP2R1 gene loci rs10741657,rs12794714.Serum 25(OH)D levels were detected,and the relationship between gene polymorphisms and NPC risk and radiotherapy response was analyzed.RESULTS The GC gene rs4588 TT genotype was significantly associated with the risk of NPC in both the codominant model[odds ratio(OR)=1.68,95%CI:1.15-2.45,P=0.007]and the recessive model(OR=1.56,95%CI:1.02-2.38,P=0.039).The association between the rs4588 TT genotype and the risk of NPC was more significant in the male subgroup(OR=1.87,95%CI:1.11-3.15,P=0.019)and the squamous cell carcinoma subgroup(OR=1.89,95%CI:1.19-3.00,P=0.007).The serum 25(OH)D level of the rs7041 AA genotype carriers was significantly lower than that of the CC genotype(P<0.001).The CYP2R1 gene rs10741657 AA genotype was associated with higher serum 25(OH)D levels(P=0.003).The rs12794714 AA genotype was associated with radiotherapy resistance(OR=1.76,95%CI:1.18-2.63,P=0.005).Stratified analysis showed that the association between rs4588 and rs12794714 was significant only in the subgroup with higher 25(OH)D levels.CONCLUSION GC and CYP2R1 genes polymorphisms are associated with NPC susceptibility and radiotherapy response,and this association may be affected by serum 25(OH)D levels.This study provides a new idea for the prevention and individualized treatment in NPC.
基金supported by National Key R&D Program of China (Grant Nos.2022-YFA1403800,2023YFA1406000,and 2023YFA1406500)the National Natural Science Foundation of China (Grant Nos.12274459,12474002,22171283,and 52130103)+1 种基金China Postdoctoral Science Foundation (Grant No.2023M730011)supported by the Synergetic Extreme Condition User Facility (SECUF,https://cstr.cn/31123.02.SECUF)。
文摘Chiral topological semimetals hosting multifold fermions and exotic surface states represent a frontier in topological materials research. Among them, noncentrosymmetric cubic B20 compounds—notably transitionmetal silicides and germanides—offer a unique platform for realizing symmetry-protected topological phases and unconventional optoelectronic responses. Here, we report the physical properties of Rh Ge and Co Ge single crystals with B20 structure in detail. Transport measurements revea metallic behavior with characteristic Fermi-liquid scaling at low temperatures, while magnetization results confirm paramagnetism in both compounds. In addition,both materials exhibit low carrier concentrations with small electronic specific heat coefficients, indicating their semimetal feature with weak electronic correlations. Such high-quality Co Ge and Rh Ge single crystals provide a material platform to explore the evolution of multifold fermions and the instability of helicoid-arc surface states with spin–orbit coupling and surface environment in B20 material systems.
基金This work was supported by the National Natural Science Foundation of China(No.21334001 and No.91127030).
文摘Herein,we report self-assembly of tadpole-like single chain polymeric nanoparticles(TPPs)and the ultrasonic response of the resultant superparticles.The TPPs are with an intramolecularly crosslinked poly(2-(methacryloyloxy)ethyl pent-4-ynoate)-rpoly(hydroxyethyl methacrylate)(PMAEP-r-PHEMA)chain as the"head"and a poly(2-(dimethylamino))ethyl methacrylate(PDMAEMA)linear chain as the"tail",and are pre-pared simply and emciently by Glaser-coupling of the pendant alkynes in the PMAEP-r-PHEMA block in the common solvent methanol.The formation of the TPPs was confirmed by gel permeation chromatograph,nuclear magnetic resonance spectroscopy,dynamic light scattering,static dynamic scattering,and transmission electron microscopy.In aqueous solution,the amphiphilic TPPs could self-assemble into regular superparticles,driven by aggregation of the hydrophobic"heads".Since in the structure there is no chain entanglement and the embedding of PDMAEMA chains disturb close-packing of the"heads",the superpartieles are responsive to a low-energy ultrasonic vibration,as evidenced by greatly enhanced release of the functional molecules from the superparticles by treatment of a low-energy ultrasound.Therefore,the superparticles should be very promising in the use as the drug carriers that can be manipulated from a long distance,considering that ultrasonic energy can be focused at a small area in a relatively long distance from the ultrasound-radiating source.
文摘A numerical model for steady state analysis and analytical expressions for the AM and FM modulation responses of DFB lasers are presented.The small signal modulation responses of 3 phase shift(PS) DFB is investigated for the first time.A new method(Vector Newton method) to obtain multiple longitudinal mode of DFB lasers is used.It is demonstrated that this method is suitable for obtaining multiple solution of high nonlinear equations.Longitudinal photon density distribution and multiple longitudinal mode of 3PS DFB and simple DFB lasers are analyzed.The results show that modulation response characteristics of 3PS DFB laser is as good as that of DFB,and PS can weaken the longitudinal spatial hole burning (LHSB) effect and is in favor of single longitudinal mode operating of lasers.
基金the National Natural Science Foundation of China Key Project(No.50238040)
文摘Single fiber pull-out testing was conducted to study the origin of the functional responses to loading of carbon fiber reinforced cement-based composites. The variation of electrical resistance with the bonding force on the fiber-matrix interface was measured. Single fiber electromechanical testing was also conducted by measuring the electrical resistance under static tension. Comparison of the results shows that the resistance increasing during single fiber pull-out is mainly due to the changes at the interface. The conduction mechanism of the composite can be explained by the tunneling model. The interfacial stress causes the deformation of interfacial structure and the interfacial debonding, which have influences on the tunneling effect and result in the change of resistance.
基金supported by the National key R & D plan for the 13th five year plan (No. 2017YFC0805200)the Qingdao science and technology plan project (No.19-3-2-6-zhc)+1 种基金the Natural Science Foundation of Shandong Province (No. ZR2019MEE118)the National Natural Science Foundation of China (No. 51974179)。
文摘To relieve dust pollution in open cut coal mines and reduce the hazards of coal dust pollution to the environment and workers we optimized the synthesis of a dust suppressant by graft copolymerization of environmentally friendly soy protein isolate with methyl methacrylate.This dust suppressant could effectively control dust pollution in open cut coal mines. The optimized conditions for graft copolymerization in this case were determined by a response surface experiment designed with Design-Expert 10 software. Characterization by scanning electron microscopy showed a significant morphology change of the dust suppressant and the generation of a rigid and dense layer on its surface after interacting with coal dust.The layer exhibited good bonding and dust suppression performance. The analysis with Fourier-transform infrared spectroscopy revealed the appearance of new absorption peaks near 1300, 1072, and 1631 cm, demonstrating effective graft copolymerization. The proposed dust suppressant exhibited excellent wind erosion resistance, with a resistance that exceeded 90% at a wind speed of 6.5 m/sec. The successful graft copolymerization and effective bonding and curing of the dust suppressant on coal dust were experimentally verified.This is of great significance to the control of coal dust pollution.
基金This work has been financially supported by the Cultivation Fund of the Key Scientific and Technical Innovation Project,Ministry of Education of China under Grant No.704031by the Natural Science Foundation of Qingdao,Grant No.05-2-JC-88.
文摘Coupled effects on a single point mooring(SPM) system subjected to the combined action of wind,waves and current are studied in this paper. Due to the complicatedness of the sea state and the huge size of the vessel,physical experimental study is both time consuming and uneconomical,whereas the numerical study is cost-effective and DNV software provides powerful SESAM software in solving the issues. This paper focuses on the modeling process of the SPM system,catenary equilibrium calculation,static analysis of the vessel in three different scenarios,and dynamic response simulation of the SPM system under environmental excitations. The three scenarios in study are as follows:the SPM is under the combined function of(a) wind,waves and current,(b) wind and waves,(c) current and waves. They are so set that one can compare the contributions of different types of loads in both static and dynamic studies. Numerical study shows that wind and current are the two major factors contributing to the mooring line tension,and surge and sway are the two dominant motions of the moored vessel subjected to environmental excitations.
文摘A two-dimensional （2D） finite element analysis was carried out to assess the time-dependent behavior of single vertical pile embedded in elasto-plastic soil. The finite element analyses were carried out using the linear elastic model for the structure of the pile, while the Mohr-Coulomb model was used for representing the soil behavior surrounding the pile. The study includes cohesionless and cohesive soil to assess the lateral response of pile in the two types of soil. The whole geoteehnical model is suitable for problem of piles to determine the design quantities such as lateral deformation, lateral soil stress and its variation with time. The model is verified based on the results of published cases and there is good comparison between the results of published ease and the present simulation model. It is found that, the pile in cohesionless soil has more resistance in the rapid loading and less one in the long term loading. On the other hand, the pile in cohesive soil shows opposite behavior.
文摘To investigate genetic factors that might help define which Crohn’s disease(CD)patients are likely to benefit from anti-tumor necrosis factor(TNF)therapy.METHODSThis was a prospective cohort study.Patients were recruited from a university digestive disease practice database.We included CD patients who received anti-TNF therapy,had available medical records(with information on treatment duration and efficacy)and who consented to participation.Patients with allergic reactions were excluded.Patients were grouped as ever-responders or non-responders.Genomic DNA was extracted from peripheral blood,and 7 single nucleotide polymorphisms(SNPs)were assessed.The main outcome measure(following exposure to the drug)was response to therapy.The patient genotypes were assessed as the predictors of outcome.Possible confounders and effect modifiers included age,gender,race,and socioeconomic status disease,as well as disease characteristics(such as Montreal criteria).RESULTS121 patients were included.Twenty-one were non-responders,and 100 were ever-responders.Fas ligand SNP(rs763110)genotype frequencies,TNF gene-308 SNP(rs1800629)genotype frequencies,and their combination,were significantly different between groups on multivariable analysis controlling for Montreal disease behavior and perianal disease.The odds of a patient with a Fas ligand CC genotype being a non-responder were four-fold higher as compared to a TC or TT genotype(P=0.009,OR=4.30,95%CI:1.45-12.80).The presence of the A(minor)TNF gene-308 allele correlated with three-fold higher odds of being a non-responder(P=0.049,OR=2.88,95%CI:1.01-8.22).Patients with the combination of the Fas ligand CC genotype and the TNF-308 A allele had nearly five-fold higher odds of being a non-responder(P=0.015,OR=4.76,95%CI:1.35-16.77).No difference was seen for the remaining SNPs.CONCLUSIONThe Fas-ligand SNP and TNF gene-308 SNP are associated with anti-TNF treatment response in CD and may help select patients likely to benefit from therapy.
文摘Study on the dynamic response, and especially the nonlinear dynamic response of stiffened plates is complicated by their discontinuity and inhomogeneity. The finite element method (FEM) and the finite strip method are usually adopted in their analysis. Although many useful conclusions have been obtained, the computational cost is enormous. Based on some assumptions, the dynamic plastic response of clamped stiffened plates with large deflections was theoretically investigated herein by a singly symmetric beam model. Firstly, the deflection conditions that a plastic string must satisfy were obtained by the linearized moment-axial force interaction curve for singly symmetric cross sections and the associated plastic flow rule. Secondly, the possible motion mechanisms of the beam under different load intensity were analysed in detail. For structures with plastic deformations, a simplified method was then given that the arbitrary impact load can be replaced equivalently by a rectangular pulse. Finally, to confirm the validity of the proposed method, the dynamic plastic response of a one-way stiffened plate with four fully clamped edges was calculated. The theoretical results were in good agreement with those of FEM. It indicates that the present calculation model is easy and feasible, and the equivalent substitution of load almost has no influence on the final deflection.
基金2018 Undergraduate Innovation and Entrepreneurship Training Program of Huanggang Normal University(201810514045)High-level Cultivation Project of Huanggang Normal University(201816703)。
文摘[Objectives]This study was conducted to screen best process parameters for making Foshou yam and honey can.[Methods]The Foshou yam produced from Wuxue was used as a raw material to prepare Foshou yam and honey nutritional can by combining Foshou yam with honey through screening,pre-cooking,filling,exhausting,cooling and other technical processes.The optimum technology parameter of Foshou yam and honey nutritional can was studied through single factor tests and response surface optimization.[Results]The optimum technical parameters of Foshou yam and honey nutritional can were citric acid concentration 0.1%,amount of edible salt 0.1%,cooking time 14 min and honey concentration 26%.Under these conditions,the final sensory score was 90.20.The prepared can was not only rich in nutrition,but also had good flavor and taste.[Conclusions]This study provides reference for the development and utilization of Foshou yam and the research and development of functional food.
基金funded by the Program of China Earthquake Science Data Sharing Platform and the Youth Fund(17404031570521)
文摘In general, the seismic response analysis in earthquake engineering assumes that the vibration parameters of the target and the contact surface of the external media are identical,i. e., single point input. However, earthquake energy has an attenuation phenomenon in wave propagation,so a wide range of soil slopes and the external medium contact surface of different input points on motion are not identical. If we consider single point input only, it may not correspond with reality, so it is necessary to carry out research on multi-point input methods. Based on the 2-D slope model,single-point input and multi-point input are performed respectively to analyze and compare their similarities and differences in the perspectives of the characteristics of seismic response of soil layer and plastic zone distribution to provide a reference for the seismic design of slopes. The results show that in the perspective of soil seismic response analysis,the peak acceleration output and peak velocity output under multi-point input are greater than the peak values under single point input at the same monitoring point,the peak appearing time is also earlier than that of the single point input; in terms of the plastic zone distribution,the multi-point effect is manifested as the presence of more obvious tensile shear failures; in the perspective of safety coefficient,the safety coefficient under each multi-point input is smaller than that of single point input,a difference of about 7 % or so. In summary,multi-point input is more reasonable and practical than single point input,so multi-point input should be considered in seismic design.
基金Project(114601034)supported by the Scholarship Award for Excellent Doctoral Students Granted by the Ministry of Education of ChinaProject(61273158)supported by the National Natural Science Foundation of China
文摘An adaptive current compensation control for a single-sided linear induction motor(SLIM) with nonlinear disturbance observer was developed. First, to maintain t-axis secondary component flux constant with consideration of the specially dynamic eddy-effect(DEE) of the SLIM, a instantaneously tracing compensation of m-axis current component was analyzed. Second,adaptive current compensation based on Taylor-discretization algorithm was proposed. Third, an effective kind of nonlinear disturbance observer(NDOB) was employed to estimate and compensate the undesired load vibrations, then the robustness of the control system could be guaranteed. Experimental verification of the feasibility of the proposed method for an SLIM control system was performed, and it showed that the proposed adaptive compensation scheme with NDOB could significantly promote speed dynamical response and minimize speed ripple under the conditions of external load coupled vibrations and unavoidable feedback control variables measured errors, i.e., current and speed.
