Management of patients with acute hemorrhage requires addressing the source of bleeding,replenishing blood volume,and addressing any coagulopathy that may be present.Assessing coagulopathy and predicting blood require...Management of patients with acute hemorrhage requires addressing the source of bleeding,replenishing blood volume,and addressing any coagulopathy that may be present.Assessing coagulopathy and predicting blood requirements in real-time in patients experiencing ongoing bleeding can pose substantial challenges.In these patients,transfusion concepts based on ratios do not effectively address coagulopathy or reduce mortality.Moreover,ratio-based concepts do not stop bleeding;instead,they just give physicians more time to identify the bleeding source and plan management strategies.In clinical practice,standard laboratory coagulation tests(SLCT)are frequently used to assess various aspects of blood clotting.However,these tests may not always offer a comprehensive under-standing of clinically significant coagulopathy and the severity of blood loss.Furthermore,the SLCT have a considerable turnaround time,which may not be ideal for making prompt clinical decisions.In recent years,there has been a growing interest in point-of-care viscoelastic assays like rotational thromboelast-ometry,which provide real-time,dynamic information about clot formation and dissolution.展开更多
Electrical energy can be harvested from the rotational kinetic energy of moving bodies,consisting of both mechanical and kinetic energy as a potential power source through electromagnetic induction,similar to wind ene...Electrical energy can be harvested from the rotational kinetic energy of moving bodies,consisting of both mechanical and kinetic energy as a potential power source through electromagnetic induction,similar to wind energy applications.In industries,rotational bodies are commonly present in operations,yet this kinetic energy remains untapped.This research explores the energy generation characteristics of two rotational body types,disk-shaped and cylinder-shaped under specific experimental setups.The hardware setup included a direct current(DC)motor driver,power supply,DC generator,mechanical support,and load resistance,while the software setup involved automation testing tools and data logging.Electromagnetic induction was used to harvest energy,and experiments were conducted at room temperature(25℃)with controlled variables like speed and friction.Results showed the disk-shaped body exhibited higher energy efficiency than the cylinder-shaped body,largely due to lower mechanical losses.The disk required only two bearings,while the cylinder required four,resulting in lower bearing losses for the disk.Additionally,the disk experienced only air friction,whereas the cylinder encountered friction from a soft,uneven rubber material,increasing surface contact losses.Under a 40 W resistive load,the disk demonstrated a 17.1%energy loss due to mechanical friction,achieving up to 15.55 J of recycled energy.Conversely,the cylinder body experienced a 48.05%energy loss,delivering only 51.95%of energy to the load.These insights suggest significant potential for designing efficient energy recycling systems in industrial settings,particularly in manufacturing and processing industries where rotational machinery is prevalent.Despite its lower energy density,this system could be beneficially integrated with energy storage solutions,enhancing sustainability in industrial practices.展开更多
This letter compares the clinical efficacy and economic feasibility of the scoliocorrector fatma-UI(SCFUI)with direct vertebral rotation(DVR)in treating adolescent idiopathic scoliosis(AIS).SCFUI has shown promising r...This letter compares the clinical efficacy and economic feasibility of the scoliocorrector fatma-UI(SCFUI)with direct vertebral rotation(DVR)in treating adolescent idiopathic scoliosis(AIS).SCFUI has shown promising results in threedimensional spinal correction,providing superior rotational alignment compared to DVR and achieving significant improvements in coronal and sagittal planes.Additionally,SCFUI’s advanced design reduces risks associated with AIS surgeries and enhances overall patient outcomes.Economic analysis reveals SCFUI as a cost-effective option,potentially lowering long-term healthcare costs by minimizing complications and revisions.Our findings suggest that SCFUI is a viable,innovative approach in AIS treatment,meeting clinical and economic demands in orthopedic care.展开更多
BACKGROUND The use of apixaban in chronic hemodialysis(HD)patients for non-valvular atrial fibrillation(NVAF)is still controversial regarding benefit of stroke protection vs risk of bleeding.Rotational thromboelastome...BACKGROUND The use of apixaban in chronic hemodialysis(HD)patients for non-valvular atrial fibrillation(NVAF)is still controversial regarding benefit of stroke protection vs risk of bleeding.Rotational thromboelastometry(ROTEM)is a point of care method that evaluates clot formation in whole blood and has been used as an evaluation tool for bleeding risk assessment in non-HD apixaban users.AIM To determine whether bleeding risk can be predicted using ROTEM activated with tissue factor(EXTEM)in HD patients receiving apixaban for NVAF.METHODS Nineteen HD patients with NVAF treated with apixaban for at least 8 days were enrolled.Four dosing regimens were recorded as prescribed by their physician,from 2.5 mg once daily on a non-dialysis day to 5 mg twice daily.Standard coagulation tests,along with ROTEM and apixaban drug levels(using liquid anti-Xa assay)were performed once on a non-dialysis day before and two hours after apixaban morning pill administration.Patients were subsequently monitored for thrombotic/bleeding events and all-cause mortality.RESULTS Over a median follow-up period of 36 months,six patients experienced a bleeding event(group A)and 13 remained free of bleeding(group B).Six deaths were recorded:Three due to major bleeding,one from thrombotic stroke,and two unrelated to coagulopathy.EXTEM clotting time(CT)-post was the only parameter that significantly differed between group A and group B(P=0.013).Each 1-second increase in CT-post was linked to an 8%higher likelihood of a bleeding event(odds ratio=1.08,95%confidence interval:1.0-1.17;P=0.048).A significant progressive increase was observed with the drug’s trough and peak levels(P<0.05)across the four dosing regimens but no significant relationship was found between CT and apixaban dose groups.CONCLUSION Early detection of bleeding risk in HD patients with NVAF on Apixaban maybe be effectively achieved through frequent monitoring using ROTEM EXTEM post CT,thereby helping to reduce associated morbidity.展开更多
Industrial processes often involve rotating machinery that generates substantial kinetic energy,much of which remains untapped.Harvesting rotational kinetic energy offers a promising solution to reduce energy waste an...Industrial processes often involve rotating machinery that generates substantial kinetic energy,much of which remains untapped.Harvesting rotational kinetic energy offers a promising solution to reduce energy waste and improve energy efficiency in industrial applications.This research investigates the potential of electromagnetic induction for harvesting rotational kinetic energy from industrial machinery.A comparative study was conducted between disk and cylinder-shaped rotational bodies to evaluate their energy efficiency under various load conditions.Experimental results demonstrated that the disk body exhibited higher energy efficiency,primarily due to lower mechanical losses compared to the cylinder body.A power management circuit was developed to regulate and store the harvested energy,integrating voltage,current,and speed sensors along with a charge controller for battery storage.The experimental setup successfully converted rotational kinetic energy into usable electrical power,with the disk achieving up to 16.33 J of recycled energy,outperforming the cylinder.The disk body demonstrated higher energy recovery efficiency compared to the cylinder,particularly under the 40 W resistive load condition.These findings demonstrate the feasibility of implementing energy recycling systems in industrial settings to enhance sustainability,reduce energy consumption,and minimize waste.Future research should focus on optimizing power management systems and improving energy harvesting efficiency to enable wider adoption of energy recycling technologies in various industrial applications.展开更多
This study investigates the nonlinear dynamic properties of rotating functionally graded sandwich rectangular plates in a thermal environment.The nonlinear vibration equations for a rotating metal-ceramic functionally...This study investigates the nonlinear dynamic properties of rotating functionally graded sandwich rectangular plates in a thermal environment.The nonlinear vibration equations for a rotating metal-ceramic functionally graded sandwich rectangular plate in a thermal environment are derived using classical thin plate theory and Hamilton’s principle,considering geometric nonlinearity,temperature-dependent material properties,and power law distribution of components through the thickness.With cantilever boundary conditions,the flexural nonlinear differential equations of the rectangular sandwich plate are obtained via the Galerkin method.Since the natural vibration differential equations exhibit nonlinear characteristics,the multiscale method is employed to derive the expression for nonlinear natural frequency.An example analysis reveals how the natural frequency of a functionally graded sandwich rectangular plate varies with rotational speed and temperature.Results show that the nonlinear/linear frequency ratio increases with rotational angular velocity Ω and thickness-to-length ratio h/a,follows a cosine-like periodic pattern with the setting angle,and shows a sharp decrease followed by a rapid increase with increasing width-to-length ratio b/a.The derived analytical solutions for nonlinear frequency provide valuable insights for assessing the dynamic characteristics of functionally graded structures.展开更多
Rotational feeding combined with shift feeding electrochemical trepanning(RF-SF ECTr)is an effective method for machining aeroengine blisks.However,given the variable relative motion of the electrodes and the complex ...Rotational feeding combined with shift feeding electrochemical trepanning(RF-SF ECTr)is an effective method for machining aeroengine blisks.However,given the variable relative motion of the electrodes and the complex flow channels around the bending and twisting blades,the accessibility and uniformity of the flow field are poor in blisk RF-SF ECTr using the traditional electrolyte supply(TES)mode,resulting in poor machining stability and low machining efficiency.To improve the distribution of the flow field,a new multi-channel electrolyte supply(MCES)mode is proposed for blisk RF-SF ECTr,in which the position and volume of the electrolyte supply are controlled effectively by setting multiple inlet channels in the liquid inlet area.A flow-field simulation comparison between TES and MCES shows that better accessibility and uniformity of the flow-field distribution are achieved under MCES.To clarify further the flow-field distribution characteristics under RF-SF ECTr,a series of flow-field simulations was conducted at different machining depths.Based on the obtained dynamic change law for the flow field,to enhance further its uniformity and accessibility,a global coverage strategy for the electrolyte supply and a flow-field structure optimization method for MCES are proposed,which involve optimizing the number,diameter,and location of the inlet channels.After many simulations,the optimal MCES structure was achieved whereby the electrolyte covers all positions effectively in the processing area.To verify the proposed method as effective and correct,a series of RF-SF ECTr experiments was carried out.Under the optimized MCES mode,the feeding rate was increased from 0.8 mm/min with the TES mode to 2.0 mm/min,and the processing stability and efficiency were improved significantly.The methods presented here offer an effective guide for flow-field optimization when machining other components with complex spatial structures.展开更多
We study the motion of an inertial microswimmer in a non-Newtonian environment with a finite memory and present the theoretical realization of an unexpected transition from random self-propulsion to rotational(circula...We study the motion of an inertial microswimmer in a non-Newtonian environment with a finite memory and present the theoretical realization of an unexpected transition from random self-propulsion to rotational(circular or elliptical)motion.Further,the rotational motion of the swimmer is followed by spontaneous local directional reversal,yet with a steady-state angular diffusion.Moreover,the advent of this behaviour is observed in the oscillatory regime of the inertia-memory parameter space of the dynamics.We quantify this unconventional rotational motion of the microswimmer by measuring the time evolution of the direction of its instantaneous velocity or orientation.By solving the generalized Langevin model of non-Markovian dynamics of an inertial active Ornstein–Uhlenbeck particle,we show that the emergence of the rotational(circular or elliptical)trajectory is due to the presence of both inertial motion and memory in the environment.展开更多
Scaffolds that emulate the architecture of human bone,combined with strong mechanical stability and biocompatibility,are vital for promoting effective bone tissue regeneration.However,most existing bone-mimetic scaffo...Scaffolds that emulate the architecture of human bone,combined with strong mechanical stability and biocompatibility,are vital for promoting effective bone tissue regeneration.However,most existing bone-mimetic scaffolds fall short in reproducing the intricate hierarchical structure of human bone,which restricts their practical application.This study introduces a novel strategy that combines rotational three-dimensional(3D)printing technology and sponge replication technique to fabricate bone-mimetic scaffolds based on composite materials comprising copper-substituted diopside and biphasic calcium phosphate.The scaffolds closely mimic the structure of human bone,featuring both cancellous and cortical bone with Haversian canals.Additionally,the scaffolds exhibit high porosity and transport capacity,while exhibiting compressive strength that is on par with human bone under both axial and lateral loads.Moreover,they demonstrate good biocompatibility and the potential to induce and support osteogenesis and angiogenesis.The scaffolds produced here present a pathway to remediating particularly large bone defects.Given their close resemblance to human bone structure and function,these scaffolds may be well-suited for developing in vitro bone disease models for pharmaceutical testing and various biomedical applications.展开更多
Cardiovascular disease is the leading cause of human mortality,and calcified tissue blocking blood vessels is the main cause of major adverse cardiovascular events(MACE).Rotational Atherectomy(RA)is a minimally invasi...Cardiovascular disease is the leading cause of human mortality,and calcified tissue blocking blood vessels is the main cause of major adverse cardiovascular events(MACE).Rotational Atherectomy(RA)is a minimally invasive catheterbased treatment method that involves high-speed cutting of calcified tissue using miniature tools for removal.However,the cutting forces,heat,and debris can induce tissue damage and give rise to serious surgical complications.To enhance the effectiveness and efficiency of RA,a novel eccentric rotational cutting tool,with one side comprising axial and circumferential staggered micro-blades,was designed and fabricated in this study.In addition,a series of experiments were conducted to analyze their performance across five dimensions:tool kinematics,force,temperature,debris,and surface morphology of the specimens.Experimental results show that the force,temperature and debris size of the novel tool were well inhibited at the highest rotational speed.For the tool of standard clinical size(diameter 1.25 mm),the maximum force is 0.75 N,with a maximum temperature rise in the operation area of 1.09℃.Debris distribution followed a normal distribution pattern,with 90%of debris measuring smaller than 9.12μm.All tool metrics met clinical safety requirements,indicating its superior performance.This study provides a new idea for the design of calcified tissue removal tools,and contributes positively to the advancement of RA.展开更多
This study conducted the experimental investigation of aerodynamic heating of Micro-scale Rotational Shearing Flow with Axial Limited-Length(MRSFALL).The temperature riseof the stator is captured by the high response ...This study conducted the experimental investigation of aerodynamic heating of Micro-scale Rotational Shearing Flow with Axial Limited-Length(MRSFALL).The temperature riseof the stator is captured by the high response thermocouples.The eccentricity ratio and clearanceheight are guaranteed by means of instantaneous trajectory and torsion monitoring of the rotator.The result shows that the maximum temperature rise takes place upstream of the minimum clear-ance height along circumferential direction.The distribution of temperature rise presents asymmet-ric curve along axial direction,and peak value occurs near the dimensionless axial position of-0.18.The effect of aerodynamic heating becomes notable as the rotational speed is larger than3×10^(4)r/min.The effect of end leakage and the viscous dissipation have great impact on temper-ature rise of MRSFALL.More specially,the peak value of temperature rise at dimensionless clear-ance height of 0.0080 is larger than the case at dimensionless clearance height of 0.0044.Furthermore,when the eccentricity ratio is too large,the viscous dissipation is induced,and theadditional temperature rise is achieved.The heat flux identification of shear flow has been realizedby Sequential Function Specification Method(SFSM)and its estimation of thermal load has been given.The heat flux induced by the aerodynamic heating in this study varies from 950 W/m^(2)to1330 W/m^(2).展开更多
Rotational dynamics simulations of neutral O_(2)molecules driven by linearly,elliptically and circularly polarized femtosecond pulsed lasers are carried out using a full quantum time-dependent wave packet evolution me...Rotational dynamics simulations of neutral O_(2)molecules driven by linearly,elliptically and circularly polarized femtosecond pulsed lasers are carried out using a full quantum time-dependent wave packet evolution method.Here,the direction of laser propagation is set along the z axis,and the polarization plane is restricted to the xy plane.The results indicate that the alignment of O_(2)molecules in the z direction is weakly affected by varying the ellipticity when the total laser intensity is held constant.For rotation within the xy plane,the linearly polarized laser significantly excites rotational motion,with the degree of excitation increasing as the ellipticity increases.In contrast,under the influence of a circularly polarized laser,the angular distribution of O_(2)molecules in the xy plane remains isotropic.Additionally,the effects of the initial rotational quantum number,the temperature of the O_(2)molecules and the nuclear spin on laser-induced alignment are discussed.展开更多
The paper is devoted to establishing the long-time behavior of solutions to the extensible beam equation with rotational inertia and nonlocal strong damping.Within the theory of asymptotical smoothness,we investigate ...The paper is devoted to establishing the long-time behavior of solutions to the extensible beam equation with rotational inertia and nonlocal strong damping.Within the theory of asymptotical smoothness,we investigate the existence of the attractor by using the contractive function method and more detailed estimates.展开更多
In this study,a novel rotational damper called a Rotational Friction Viscoelastic Damper(RFVD) is introduced.Some viscoelastic pads are added to the Rotational Friction Damper(RFD) in addition to the friction discs us...In this study,a novel rotational damper called a Rotational Friction Viscoelastic Damper(RFVD) is introduced.Some viscoelastic pads are added to the Rotational Friction Damper(RFD) in addition to the friction discs used in this conventional device.Consequently,the amount of energy dissipated by the damper increases in low excitation frequencies.In fact,the input energy to the structure is simultaneously dissipated in the form of friction and heat by frictional discs and viscoelastic pads.In order to compare the performance of this novel damper with the earlier types,a set of experiments were carried out.According to the test results,the RFVD showed a better performance in dissipating input energy to the structure when compared to the RFD.The seismic behavior of steel frames equipped with these dampers was also numerically evaluated based on a nonlinear time history analysis.The numerical results verifi ed the performance of the dampers in increasing the energy dissipation and decreasing the energy input to the structural elements.In order to achieve the maximum dissipated energy,the dampers need to be installed in certain places called critical points in the structure.An appropriate approach is presented to properly fi nd these points.Finally,the performance of the RFVDs installed at these critical points was investigated in comparison to some other confi gurations and the validity of the suggested method in increasing the energy dissipation was confi rmed.展开更多
Based on the ERA5 reanalysis datasets during 1980-2019,a total of eleven zonal shear lines(ZSLs)that caused heavy precipitation and lasted more than 60 hours over the Tibetan Plateau in summer are selected for composi...Based on the ERA5 reanalysis datasets during 1980-2019,a total of eleven zonal shear lines(ZSLs)that caused heavy precipitation and lasted more than 60 hours over the Tibetan Plateau in summer are selected for composite analysis.By decomposing the kinetic energy(K)near the ZSL into divergent and rotational kinetic energies(K_(D)and K_(R))and the kinetic energy of interaction between the divergent wind and the rotational wind(K_(R)D),the influence of the rotational and divergent winds on the evolution of the ZSL intensity is investigated from the perspective of K_(D)and K_(R).The main results are as follows.The ZSL is a comprehensive reflection of rotation and convergence.The intensity evolution of ZSL is essentially synchronized with those of K,K_(R),and K_(RD)but lags behind K_(D)by about three hours.The enhancement of K is mainly contributed by K_(R),which is governed by the conversion from K_(D)to K_(R).Furthermore,the increase in the conversion from K_(D)to K_(R)is controlled by the geostrophic effect term Af,which is determined by the joint enhancement of the zonal rotational and meridional divergent wind components(u_(R)and v_(D)).Therefore,the joint enhancement of u_(R)and v_(D)controls the increase of the ZSL intensity,leading to increased precipitation.展开更多
Rotational isomerism effects on the optical spectra of a push-pull nonlinear optical chro-mophore 2-dicyanomethylen-3-cyano-4-f2-[E-（4-N,N-di（2-acetoxyethyl）-amino）-phenylene-（3,4-dibutyl）-thien-5]-E-vinylg-5,5-...Rotational isomerism effects on the optical spectra of a push-pull nonlinear optical chro-mophore 2-dicyanomethylen-3-cyano-4-f2-[E-（4-N,N-di（2-acetoxyethyl）-amino）-phenylene-（3,4-dibutyl）-thien-5]-E-vinylg-5,5-dimethyl-2,5-dihydrofuran （FTC） in a few solvents have been studied using the time-dependent density functional theory in combination with the polarizable continuum model. It is shown that the maximum absorption peaks of the ro-tamers have difference of nearly 30 nm both in vacuum and in solutions. The population of the rotamers changes a lot in different solvents. Based on the geometries optimized by Hartree-Fock method, the Maxwell-Boltzmann averaged absorption has been calculated and the maximum absorption peak is in good agreement with experiment. It indicates that the bond length alternation can have an important effect on the optical spectra.展开更多
Here wc report calculation of the differential interference angles （including b≤p gild b≥p ） for singlet-triplet mixed states of Na2（A^1∑u^＋,ν=8-b^3∏0u,ν=14） system in collision with Na, in order to study t...Here wc report calculation of the differential interference angles （including b≤p gild b≥p ） for singlet-triplet mixed states of Na2（A^1∑u^＋,ν=8-b^3∏0u,ν=14） system in collision with Na, in order to study the collision- induced quantum interference on rotational energy transfer in an atom-diatom system. The calculation is based on the first-order Born approximation of time-dependent perturbation theory, and the anisotropic Lennard-Jones intcraction potentials are also employed, The relationships between differential interference angle and impact parameter, including collision diameter and velocity, are obtained,展开更多
Based on the first-order shear deformation theory,a 3-node co-rotational triangular finite element formulation is developed for large deformation modeling of non-smooth,folded and multi-shell laminated composite struc...Based on the first-order shear deformation theory,a 3-node co-rotational triangular finite element formulation is developed for large deformation modeling of non-smooth,folded and multi-shell laminated composite structures.The two smaller components of the mid-surface normal vector of shell at a node are defined as nodal rotational variables in the co-rotational local coordinate system.In the global coordinate system,two smaller components of one vector,together with the smallest or second smallest component of another vector,of an orthogonal triad at a node on a non-smooth intersection of plates and/or shells are defined as rotational variables,whereas the two smaller components of the mid-surface normal vector at a node on the smooth part of the plate or shell(away from non-smooth intersections)are defined as rotational variables.All these vectorial rotational variables can be updated in an additive manner during an incremental solution procedure,and thus improve the computational efficiency in the nonlinear solution of these composite shell structures.Due to the commutativity of all nodal variables in calculating of the second derivatives of the local nodal variables with respect to global nodal variables,and the second derivatives of the strain energy functional with respect to local nodal variables,symmetric tangent stiffness matrices in local and global coordinate systems are obtained.To overcome shear locking,the assumed transverse shear strains obtained from the line-integration approach are employed.The reliability and computational accuracy of the present 3-node triangular shell finite element are verified through modeling two patch tests,several smooth and non-smooth laminated composite shells undergoing large displacements and large rotations.展开更多
Aimed at the large deformation problem of industry cooling tower shell, the mathematical model for the random response of rotational shell under the external random excitation is established by statistic perturbation ...Aimed at the large deformation problem of industry cooling tower shell, the mathematical model for the random response of rotational shell under the external random excitation is established by statistic perturbation method. The effect of nonlinear geometric behavior on the response of rotational shell is analyzed.展开更多
Based on the theoretical analysis of nonlinear random response of structure, for the engineering practical problem, that is, the large deformation of industry cooling tower shell structure under the action of strong w...Based on the theoretical analysis of nonlinear random response of structure, for the engineering practical problem, that is, the large deformation of industry cooling tower shell structure under the action of strong wind loads, the statistic perturbation method is also used to analyze some statistic characteristics of the nonlinear random response of rotational shell with geometric nonlinearity and stationary strong wind load considered. Through computation, some average values of nornal displacements and the nonlinear effect factor of the cooling tower shell are given.展开更多
文摘Management of patients with acute hemorrhage requires addressing the source of bleeding,replenishing blood volume,and addressing any coagulopathy that may be present.Assessing coagulopathy and predicting blood requirements in real-time in patients experiencing ongoing bleeding can pose substantial challenges.In these patients,transfusion concepts based on ratios do not effectively address coagulopathy or reduce mortality.Moreover,ratio-based concepts do not stop bleeding;instead,they just give physicians more time to identify the bleeding source and plan management strategies.In clinical practice,standard laboratory coagulation tests(SLCT)are frequently used to assess various aspects of blood clotting.However,these tests may not always offer a comprehensive under-standing of clinically significant coagulopathy and the severity of blood loss.Furthermore,the SLCT have a considerable turnaround time,which may not be ideal for making prompt clinical decisions.In recent years,there has been a growing interest in point-of-care viscoelastic assays like rotational thromboelast-ometry,which provide real-time,dynamic information about clot formation and dissolution.
基金The APC was funded by Research Management Center, Multimedia University, Malaysia.
文摘Electrical energy can be harvested from the rotational kinetic energy of moving bodies,consisting of both mechanical and kinetic energy as a potential power source through electromagnetic induction,similar to wind energy applications.In industries,rotational bodies are commonly present in operations,yet this kinetic energy remains untapped.This research explores the energy generation characteristics of two rotational body types,disk-shaped and cylinder-shaped under specific experimental setups.The hardware setup included a direct current(DC)motor driver,power supply,DC generator,mechanical support,and load resistance,while the software setup involved automation testing tools and data logging.Electromagnetic induction was used to harvest energy,and experiments were conducted at room temperature(25℃)with controlled variables like speed and friction.Results showed the disk-shaped body exhibited higher energy efficiency than the cylinder-shaped body,largely due to lower mechanical losses.The disk required only two bearings,while the cylinder required four,resulting in lower bearing losses for the disk.Additionally,the disk experienced only air friction,whereas the cylinder encountered friction from a soft,uneven rubber material,increasing surface contact losses.Under a 40 W resistive load,the disk demonstrated a 17.1%energy loss due to mechanical friction,achieving up to 15.55 J of recycled energy.Conversely,the cylinder body experienced a 48.05%energy loss,delivering only 51.95%of energy to the load.These insights suggest significant potential for designing efficient energy recycling systems in industrial settings,particularly in manufacturing and processing industries where rotational machinery is prevalent.Despite its lower energy density,this system could be beneficially integrated with energy storage solutions,enhancing sustainability in industrial practices.
文摘This letter compares the clinical efficacy and economic feasibility of the scoliocorrector fatma-UI(SCFUI)with direct vertebral rotation(DVR)in treating adolescent idiopathic scoliosis(AIS).SCFUI has shown promising results in threedimensional spinal correction,providing superior rotational alignment compared to DVR and achieving significant improvements in coronal and sagittal planes.Additionally,SCFUI’s advanced design reduces risks associated with AIS surgeries and enhances overall patient outcomes.Economic analysis reveals SCFUI as a cost-effective option,potentially lowering long-term healthcare costs by minimizing complications and revisions.Our findings suggest that SCFUI is a viable,innovative approach in AIS treatment,meeting clinical and economic demands in orthopedic care.
文摘BACKGROUND The use of apixaban in chronic hemodialysis(HD)patients for non-valvular atrial fibrillation(NVAF)is still controversial regarding benefit of stroke protection vs risk of bleeding.Rotational thromboelastometry(ROTEM)is a point of care method that evaluates clot formation in whole blood and has been used as an evaluation tool for bleeding risk assessment in non-HD apixaban users.AIM To determine whether bleeding risk can be predicted using ROTEM activated with tissue factor(EXTEM)in HD patients receiving apixaban for NVAF.METHODS Nineteen HD patients with NVAF treated with apixaban for at least 8 days were enrolled.Four dosing regimens were recorded as prescribed by their physician,from 2.5 mg once daily on a non-dialysis day to 5 mg twice daily.Standard coagulation tests,along with ROTEM and apixaban drug levels(using liquid anti-Xa assay)were performed once on a non-dialysis day before and two hours after apixaban morning pill administration.Patients were subsequently monitored for thrombotic/bleeding events and all-cause mortality.RESULTS Over a median follow-up period of 36 months,six patients experienced a bleeding event(group A)and 13 remained free of bleeding(group B).Six deaths were recorded:Three due to major bleeding,one from thrombotic stroke,and two unrelated to coagulopathy.EXTEM clotting time(CT)-post was the only parameter that significantly differed between group A and group B(P=0.013).Each 1-second increase in CT-post was linked to an 8%higher likelihood of a bleeding event(odds ratio=1.08,95%confidence interval:1.0-1.17;P=0.048).A significant progressive increase was observed with the drug’s trough and peak levels(P<0.05)across the four dosing regimens but no significant relationship was found between CT and apixaban dose groups.CONCLUSION Early detection of bleeding risk in HD patients with NVAF on Apixaban maybe be effectively achieved through frequent monitoring using ROTEM EXTEM post CT,thereby helping to reduce associated morbidity.
文摘Industrial processes often involve rotating machinery that generates substantial kinetic energy,much of which remains untapped.Harvesting rotational kinetic energy offers a promising solution to reduce energy waste and improve energy efficiency in industrial applications.This research investigates the potential of electromagnetic induction for harvesting rotational kinetic energy from industrial machinery.A comparative study was conducted between disk and cylinder-shaped rotational bodies to evaluate their energy efficiency under various load conditions.Experimental results demonstrated that the disk body exhibited higher energy efficiency,primarily due to lower mechanical losses compared to the cylinder body.A power management circuit was developed to regulate and store the harvested energy,integrating voltage,current,and speed sensors along with a charge controller for battery storage.The experimental setup successfully converted rotational kinetic energy into usable electrical power,with the disk achieving up to 16.33 J of recycled energy,outperforming the cylinder.The disk body demonstrated higher energy recovery efficiency compared to the cylinder,particularly under the 40 W resistive load condition.These findings demonstrate the feasibility of implementing energy recycling systems in industrial settings to enhance sustainability,reduce energy consumption,and minimize waste.Future research should focus on optimizing power management systems and improving energy harvesting efficiency to enable wider adoption of energy recycling technologies in various industrial applications.
基金supported by the National Natural Science Foundation of China(No.11772090).
文摘This study investigates the nonlinear dynamic properties of rotating functionally graded sandwich rectangular plates in a thermal environment.The nonlinear vibration equations for a rotating metal-ceramic functionally graded sandwich rectangular plate in a thermal environment are derived using classical thin plate theory and Hamilton’s principle,considering geometric nonlinearity,temperature-dependent material properties,and power law distribution of components through the thickness.With cantilever boundary conditions,the flexural nonlinear differential equations of the rectangular sandwich plate are obtained via the Galerkin method.Since the natural vibration differential equations exhibit nonlinear characteristics,the multiscale method is employed to derive the expression for nonlinear natural frequency.An example analysis reveals how the natural frequency of a functionally graded sandwich rectangular plate varies with rotational speed and temperature.Results show that the nonlinear/linear frequency ratio increases with rotational angular velocity Ω and thickness-to-length ratio h/a,follows a cosine-like periodic pattern with the setting angle,and shows a sharp decrease followed by a rapid increase with increasing width-to-length ratio b/a.The derived analytical solutions for nonlinear frequency provide valuable insights for assessing the dynamic characteristics of functionally graded structures.
基金Supported by National Natural Science Foundation of China(Grant Nos.52275435,52075465,52375519)Open Fund Project of Jiangsu Key Laboratory of Precision and Micro-manufacturing Technology(Grant No.JSKL2324K03)Key Research and Development Program of Hunan Province of China(Grant No.2023GK2026)。
文摘Rotational feeding combined with shift feeding electrochemical trepanning(RF-SF ECTr)is an effective method for machining aeroengine blisks.However,given the variable relative motion of the electrodes and the complex flow channels around the bending and twisting blades,the accessibility and uniformity of the flow field are poor in blisk RF-SF ECTr using the traditional electrolyte supply(TES)mode,resulting in poor machining stability and low machining efficiency.To improve the distribution of the flow field,a new multi-channel electrolyte supply(MCES)mode is proposed for blisk RF-SF ECTr,in which the position and volume of the electrolyte supply are controlled effectively by setting multiple inlet channels in the liquid inlet area.A flow-field simulation comparison between TES and MCES shows that better accessibility and uniformity of the flow-field distribution are achieved under MCES.To clarify further the flow-field distribution characteristics under RF-SF ECTr,a series of flow-field simulations was conducted at different machining depths.Based on the obtained dynamic change law for the flow field,to enhance further its uniformity and accessibility,a global coverage strategy for the electrolyte supply and a flow-field structure optimization method for MCES are proposed,which involve optimizing the number,diameter,and location of the inlet channels.After many simulations,the optimal MCES structure was achieved whereby the electrolyte covers all positions effectively in the processing area.To verify the proposed method as effective and correct,a series of RF-SF ECTr experiments was carried out.Under the optimized MCES mode,the feeding rate was increased from 0.8 mm/min with the TES mode to 2.0 mm/min,and the processing stability and efficiency were improved significantly.The methods presented here offer an effective guide for flow-field optimization when machining other components with complex spatial structures.
基金the 8th Statphysics Community Meeting(ICTS/ISPCM2023/02)during which we had lots of fruitful discussionsMS acknowledges the start-up grant from UGC,SERB-SURE grant(SUR/2022/000377),CRG grant(CRG/2023/002026)from DST,Govt.of India for the financial support。
文摘We study the motion of an inertial microswimmer in a non-Newtonian environment with a finite memory and present the theoretical realization of an unexpected transition from random self-propulsion to rotational(circular or elliptical)motion.Further,the rotational motion of the swimmer is followed by spontaneous local directional reversal,yet with a steady-state angular diffusion.Moreover,the advent of this behaviour is observed in the oscillatory regime of the inertia-memory parameter space of the dynamics.We quantify this unconventional rotational motion of the microswimmer by measuring the time evolution of the direction of its instantaneous velocity or orientation.By solving the generalized Langevin model of non-Markovian dynamics of an inertial active Ornstein–Uhlenbeck particle,we show that the emergence of the rotational(circular or elliptical)trajectory is due to the presence of both inertial motion and memory in the environment.
文摘Scaffolds that emulate the architecture of human bone,combined with strong mechanical stability and biocompatibility,are vital for promoting effective bone tissue regeneration.However,most existing bone-mimetic scaffolds fall short in reproducing the intricate hierarchical structure of human bone,which restricts their practical application.This study introduces a novel strategy that combines rotational three-dimensional(3D)printing technology and sponge replication technique to fabricate bone-mimetic scaffolds based on composite materials comprising copper-substituted diopside and biphasic calcium phosphate.The scaffolds closely mimic the structure of human bone,featuring both cancellous and cortical bone with Haversian canals.Additionally,the scaffolds exhibit high porosity and transport capacity,while exhibiting compressive strength that is on par with human bone under both axial and lateral loads.Moreover,they demonstrate good biocompatibility and the potential to induce and support osteogenesis and angiogenesis.The scaffolds produced here present a pathway to remediating particularly large bone defects.Given their close resemblance to human bone structure and function,these scaffolds may be well-suited for developing in vitro bone disease models for pharmaceutical testing and various biomedical applications.
基金Supported by National Natural Science Foundation of China(Grant No.52205455)Fujian Provincial Health Technology Project(Grant Nos.2022CXA005,2022CXA015)。
文摘Cardiovascular disease is the leading cause of human mortality,and calcified tissue blocking blood vessels is the main cause of major adverse cardiovascular events(MACE).Rotational Atherectomy(RA)is a minimally invasive catheterbased treatment method that involves high-speed cutting of calcified tissue using miniature tools for removal.However,the cutting forces,heat,and debris can induce tissue damage and give rise to serious surgical complications.To enhance the effectiveness and efficiency of RA,a novel eccentric rotational cutting tool,with one side comprising axial and circumferential staggered micro-blades,was designed and fabricated in this study.In addition,a series of experiments were conducted to analyze their performance across five dimensions:tool kinematics,force,temperature,debris,and surface morphology of the specimens.Experimental results show that the force,temperature and debris size of the novel tool were well inhibited at the highest rotational speed.For the tool of standard clinical size(diameter 1.25 mm),the maximum force is 0.75 N,with a maximum temperature rise in the operation area of 1.09℃.Debris distribution followed a normal distribution pattern,with 90%of debris measuring smaller than 9.12μm.All tool metrics met clinical safety requirements,indicating its superior performance.This study provides a new idea for the design of calcified tissue removal tools,and contributes positively to the advancement of RA.
基金supports from the National Natural Science Foundation of China(No.52206091)the Aeronautical Science Foundation of China(No.201928052008)the Natural Science Foundation of Jiangsu Province,China(No.BK20210303)。
文摘This study conducted the experimental investigation of aerodynamic heating of Micro-scale Rotational Shearing Flow with Axial Limited-Length(MRSFALL).The temperature riseof the stator is captured by the high response thermocouples.The eccentricity ratio and clearanceheight are guaranteed by means of instantaneous trajectory and torsion monitoring of the rotator.The result shows that the maximum temperature rise takes place upstream of the minimum clear-ance height along circumferential direction.The distribution of temperature rise presents asymmet-ric curve along axial direction,and peak value occurs near the dimensionless axial position of-0.18.The effect of aerodynamic heating becomes notable as the rotational speed is larger than3×10^(4)r/min.The effect of end leakage and the viscous dissipation have great impact on temper-ature rise of MRSFALL.More specially,the peak value of temperature rise at dimensionless clear-ance height of 0.0080 is larger than the case at dimensionless clearance height of 0.0044.Furthermore,when the eccentricity ratio is too large,the viscous dissipation is induced,and theadditional temperature rise is achieved.The heat flux identification of shear flow has been realizedby Sequential Function Specification Method(SFSM)and its estimation of thermal load has been given.The heat flux induced by the aerodynamic heating in this study varies from 950 W/m^(2)to1330 W/m^(2).
基金supported by the National Key Research and Development Program of China(Grant No.2022YFA1602502)the National Natural Science Foundation of China(Grant No.12450404).
文摘Rotational dynamics simulations of neutral O_(2)molecules driven by linearly,elliptically and circularly polarized femtosecond pulsed lasers are carried out using a full quantum time-dependent wave packet evolution method.Here,the direction of laser propagation is set along the z axis,and the polarization plane is restricted to the xy plane.The results indicate that the alignment of O_(2)molecules in the z direction is weakly affected by varying the ellipticity when the total laser intensity is held constant.For rotation within the xy plane,the linearly polarized laser significantly excites rotational motion,with the degree of excitation increasing as the ellipticity increases.In contrast,under the influence of a circularly polarized laser,the angular distribution of O_(2)molecules in the xy plane remains isotropic.Additionally,the effects of the initial rotational quantum number,the temperature of the O_(2)molecules and the nuclear spin on laser-induced alignment are discussed.
基金Supported by the National Natural Science Foundation of China(Grant Nos.1210150211961059)the University Innovation Project of Gansu Province(Grant No.2023B-062).
文摘The paper is devoted to establishing the long-time behavior of solutions to the extensible beam equation with rotational inertia and nonlocal strong damping.Within the theory of asymptotical smoothness,we investigate the existence of the attractor by using the contractive function method and more detailed estimates.
文摘In this study,a novel rotational damper called a Rotational Friction Viscoelastic Damper(RFVD) is introduced.Some viscoelastic pads are added to the Rotational Friction Damper(RFD) in addition to the friction discs used in this conventional device.Consequently,the amount of energy dissipated by the damper increases in low excitation frequencies.In fact,the input energy to the structure is simultaneously dissipated in the form of friction and heat by frictional discs and viscoelastic pads.In order to compare the performance of this novel damper with the earlier types,a set of experiments were carried out.According to the test results,the RFVD showed a better performance in dissipating input energy to the structure when compared to the RFD.The seismic behavior of steel frames equipped with these dampers was also numerically evaluated based on a nonlinear time history analysis.The numerical results verifi ed the performance of the dampers in increasing the energy dissipation and decreasing the energy input to the structural elements.In order to achieve the maximum dissipated energy,the dampers need to be installed in certain places called critical points in the structure.An appropriate approach is presented to properly fi nd these points.Finally,the performance of the RFVDs installed at these critical points was investigated in comparison to some other confi gurations and the validity of the suggested method in increasing the energy dissipation was confi rmed.
基金the Key Program of the National Science Foundation of China(Grant No.42030611)the Second Tibetan Plateau Scientific Expedition and Research(STEP)program(Grant No.2019QZKK0105)+1 种基金the Integration Project of Major Research Program of the National Natural Science Foundation of China(Grant No.91937301)the General Program of the National Science Foundation of China(Grant No.42175008).
文摘Based on the ERA5 reanalysis datasets during 1980-2019,a total of eleven zonal shear lines(ZSLs)that caused heavy precipitation and lasted more than 60 hours over the Tibetan Plateau in summer are selected for composite analysis.By decomposing the kinetic energy(K)near the ZSL into divergent and rotational kinetic energies(K_(D)and K_(R))and the kinetic energy of interaction between the divergent wind and the rotational wind(K_(R)D),the influence of the rotational and divergent winds on the evolution of the ZSL intensity is investigated from the perspective of K_(D)and K_(R).The main results are as follows.The ZSL is a comprehensive reflection of rotation and convergence.The intensity evolution of ZSL is essentially synchronized with those of K,K_(R),and K_(RD)but lags behind K_(D)by about three hours.The enhancement of K is mainly contributed by K_(R),which is governed by the conversion from K_(D)to K_(R).Furthermore,the increase in the conversion from K_(D)to K_(R)is controlled by the geostrophic effect term Af,which is determined by the joint enhancement of the zonal rotational and meridional divergent wind components(u_(R)and v_(D)).Therefore,the joint enhancement of u_(R)and v_(D)controls the increase of the ZSL intensity,leading to increased precipitation.
基金ACKNOWLEDGMENTS This work was supported by Young Scientists Fund of the National Natural Science Foundation of China （No.10904085）.
文摘Rotational isomerism effects on the optical spectra of a push-pull nonlinear optical chro-mophore 2-dicyanomethylen-3-cyano-4-f2-[E-（4-N,N-di（2-acetoxyethyl）-amino）-phenylene-（3,4-dibutyl）-thien-5]-E-vinylg-5,5-dimethyl-2,5-dihydrofuran （FTC） in a few solvents have been studied using the time-dependent density functional theory in combination with the polarizable continuum model. It is shown that the maximum absorption peaks of the ro-tamers have difference of nearly 30 nm both in vacuum and in solutions. The population of the rotamers changes a lot in different solvents. Based on the geometries optimized by Hartree-Fock method, the Maxwell-Boltzmann averaged absorption has been calculated and the maximum absorption peak is in good agreement with experiment. It indicates that the bond length alternation can have an important effect on the optical spectra.
基金This work was supported by National Natural Science Foundation of China(No.10374040).
文摘Here wc report calculation of the differential interference angles （including b≤p gild b≥p ） for singlet-triplet mixed states of Na2（A^1∑u^＋,ν=8-b^3∏0u,ν=14） system in collision with Na, in order to study the collision- induced quantum interference on rotational energy transfer in an atom-diatom system. The calculation is based on the first-order Born approximation of time-dependent perturbation theory, and the anisotropic Lennard-Jones intcraction potentials are also employed, The relationships between differential interference angle and impact parameter, including collision diameter and velocity, are obtained,
基金This work was supported by National Natural Science Foundation of China under Grant 11672266.
文摘Based on the first-order shear deformation theory,a 3-node co-rotational triangular finite element formulation is developed for large deformation modeling of non-smooth,folded and multi-shell laminated composite structures.The two smaller components of the mid-surface normal vector of shell at a node are defined as nodal rotational variables in the co-rotational local coordinate system.In the global coordinate system,two smaller components of one vector,together with the smallest or second smallest component of another vector,of an orthogonal triad at a node on a non-smooth intersection of plates and/or shells are defined as rotational variables,whereas the two smaller components of the mid-surface normal vector at a node on the smooth part of the plate or shell(away from non-smooth intersections)are defined as rotational variables.All these vectorial rotational variables can be updated in an additive manner during an incremental solution procedure,and thus improve the computational efficiency in the nonlinear solution of these composite shell structures.Due to the commutativity of all nodal variables in calculating of the second derivatives of the local nodal variables with respect to global nodal variables,and the second derivatives of the strain energy functional with respect to local nodal variables,symmetric tangent stiffness matrices in local and global coordinate systems are obtained.To overcome shear locking,the assumed transverse shear strains obtained from the line-integration approach are employed.The reliability and computational accuracy of the present 3-node triangular shell finite element are verified through modeling two patch tests,several smooth and non-smooth laminated composite shells undergoing large displacements and large rotations.
文摘Aimed at the large deformation problem of industry cooling tower shell, the mathematical model for the random response of rotational shell under the external random excitation is established by statistic perturbation method. The effect of nonlinear geometric behavior on the response of rotational shell is analyzed.
文摘Based on the theoretical analysis of nonlinear random response of structure, for the engineering practical problem, that is, the large deformation of industry cooling tower shell structure under the action of strong wind loads, the statistic perturbation method is also used to analyze some statistic characteristics of the nonlinear random response of rotational shell with geometric nonlinearity and stationary strong wind load considered. Through computation, some average values of nornal displacements and the nonlinear effect factor of the cooling tower shell are given.
