Looped light in a recent sophisticated real three-slit experiment is interpreted as a strong justification of the old theoretical Peano-Hilbert spacetime model of Ord and El Naschie. This in turn entails the existence...Looped light in a recent sophisticated real three-slit experiment is interpreted as a strong justification of the old theoretical Peano-Hilbert spacetime model of Ord and El Naschie. This in turn entails the existence of extra fractal dimensions and consequently of real dark energy density in full agreement with previous analysis as well as accurate measurements and observations of COBE, WMAP, and the type 1a supernova.展开更多
A power flow analysis method for weakly looped distribution systems with PV buses is proposed in this paper. The proposed method is computationally more efficient and more robust compared with the conventional compens...A power flow analysis method for weakly looped distribution systems with PV buses is proposed in this paper. The proposed method is computationally more efficient and more robust compared with the conventional compensation methods. The robustness is achieved by embedding the boundary conditions of loops and PV buses into the Jacobian matrix. The computational efficiency is achieved by the carefully designed factorization of Jacobian matrix. Test results on a 33 bus system are presented.展开更多
This study explores the clinical application of the circular wide and deep(looped,broad,and deep buried,LBD)suture technique for scar resection and examines its clinical effectiveness for scar treatment.From June 2017...This study explores the clinical application of the circular wide and deep(looped,broad,and deep buried,LBD)suture technique for scar resection and examines its clinical effectiveness for scar treatment.From June 2017 to March 2019,a total of 68 patients with scars were sutured using LBD technique,and recovery was achieved 24 months postoperatively.In all 68 patients,postoperative scars were slightly evident in two cases of cervical scar,one case of leg scar,and one case of chest scar.In addition,the remaining 62 patients were completely satisfied with the outcome.The LBD suturing technique could provide sustained and stable tension-reducing effects postoperatively and significantly improve scar formation in patients.This method is most applicable to incisions with tension.Therefore,it should be more widely used for clinical scar treatment.展开更多
In this investigation, a novel thermally coupled reactor （TCR） containing methyl formate （MF） production in the endothermic side and methanol synthesis in the exothermic side has been investigated. The interesting...In this investigation, a novel thermally coupled reactor （TCR） containing methyl formate （MF） production in the endothermic side and methanol synthesis in the exothermic side has been investigated. The interesting feature of this TCR is that productive methanol in the exothermic side could be recycled and used as feed of endothermic side for MF synthesis. Other important advantages of the proposed system are high production rates of hydrogen and MF. The configuration consists of two thermally coupled concentric tubular reactors. In these coupled reactors, autothermal system is obtained within the reactor. A steady-state heterogeneous model is used for simulation of the coupled reactor. The proposed model has been utilized to compare the performance of TCR with the conventional methanol reactor （CMR）. Noticeable enhancement can be obtained in the performance of the reactors. The influence of operational parameters is studied on reactor performance. The results show that coupling of these reactions could be feasible and beneficial. Experimental proof-of-concept is required to validate the operation of the novel reactor.展开更多
We give a mathematical golden mean distribution based probabilistic confirmation of a recent spectacular experiment with light. The experiment in question is a three-slit variant of the well known two-slit set up of q...We give a mathematical golden mean distribution based probabilistic confirmation of a recent spectacular experiment with light. The experiment in question is a three-slit variant of the well known two-slit set up of quantum mechanics. The outcome of the sophisticated experiment revealed the looped path of light on the quantum scale and consequently the Peano-Hilbert geometry of spacetime, ergo its fractal-Cantorian nature. The mathematics used here on the other hand is the remarkably simple and insightful golden mean probability distribution known from a famous paradox known in social sciences as the voter paradox.展开更多
Rheumatoid arthritis(RA)is an autoimmune disease characterized by inflammation and abnormal osteoclast activation,leading to bone destruction.We previously demonstrated that the large extracellular loop(LEL)of Tm4sf19...Rheumatoid arthritis(RA)is an autoimmune disease characterized by inflammation and abnormal osteoclast activation,leading to bone destruction.We previously demonstrated that the large extracellular loop(LEL)of Tm4sf19 is important for its function in osteoclast differentiation,and LEL-Fc,a competitive inhibitor of Tm4sf19,effectively suppresses osteoclast multinucleation and prevent bone loss associated with osteoporosis.This study aimed to investigate the role of Tm4sf19 in RA,an inflammatory and abnormal osteoclast disease,using a mouse model of collagen-induced arthritis(CIA).Tm4sf19 expression was observed in macrophages and osteoclasts within the inflamed synovium,and Tm4sf19 expression was increased together with inflammatory genes in the joint bones of CIA-induced mice compared with the sham control group.Inhibition of Tm4sf19 by LEL-Fc demonstrated both preventive and therapeutic effects in a CIA mouse model,reducing the CIA score,swelling,inflammation,cartilage damage,and bone damage.Knockout of Tm4sf19 gene or inhibition of Tm4sf19 activity by LEL-Fc suppressed LPS/IFN-γ-induced TLR4-mediated inflammatory signaling in macrophages.LEL-Fc disrupted not only the interaction between Tm4sf19 and TLR4/MD2,but also the interaction between TLR4 and MD2.μCT analysis showed that LEL-Fc treatment significantly reduced joint bone destruction and bone loss caused by hyperactivated osteoclasts in CIA mice.Taken together,these findings suggest that LELFc may be a potential treatment for RA and RA-induced osteoporosis by simultaneously targeting joint inflammation and bone destruction caused by abnormal osteoclast activation.展开更多
The aim of this paper is to present the design and experimental validation process for a thermoacoustic looped-tube engine. The design procedure consists of numerical modelling of the system using DELTA EC tool, Desig...The aim of this paper is to present the design and experimental validation process for a thermoacoustic looped-tube engine. The design procedure consists of numerical modelling of the system using DELTA EC tool, Design Environment for Low-amplitude ThermoAcousfic Energy Conversion, in particular the effects of mean pressure and regenerator configuration on the pressure amplitude and acoustic power generated. This is followed by the construction of a practical engine system equipped with a ceramic regenerator - a substrate used in auto- motive catalytic converters with fine square channels. The preliminary testing results are obtained and compared with the simulations in detail.The measurement results agree very well on the qualitative level and are reasonably close in the quantitative sense.展开更多
As space technology advances,thermal control systems must effectively collect and dissipate heat from distributed,multi-source environments.Loop heat pipe is a highly reliable two-phase heat transfer component,but it ...As space technology advances,thermal control systems must effectively collect and dissipate heat from distributed,multi-source environments.Loop heat pipe is a highly reliable two-phase heat transfer component,but it has several limitations when addressing multi-source heat dissipation.Inspired by the transport and heat dissipation system of plants,large trees achieve stable and efficient liquid supply under the influence of two driving forces:capillary force during transpiration in the leaves(pull)and root pressure generated by osmotic pressure in the roots(push).The root pressure provides an effective liquid supply with a driving force exceeding 2 MPa,far greater than the driving force in conventional capillary-pumped two-phase loops.Research has shown that osmotic heat pipes offer a powerful driving force,and combining osmotic pressure with capillary force has significant advantages.Therefore,this paper designs a multi-evaporator,dual-drive two-phase loop,using both osmotic pressure and capillary force to solve the multi-source heat dissipation challenge.First,a transmembrane water flux model for the osmotic pressure-driven device was established to predict the maximum heat transfer capacity of the dual-drive two-phase loop.Then,an experimental setup for a multi-evaporator“osmotic pressure+capillary force”dual-drive two-phase loop was constructed,capable of transferring at least 235 W of power under a reverse gravity condition of 20 m.The study also analyzed the effects of reverse gravity height,heat load distribution among the three evaporators,startup sequence,and varying branch resistances on the performance of the dual-drive two-phase loop.展开更多
This paper presents a compact ultra-low-power phase-locked loop (PLL) based binary phase-shift keying(BPSK)demodulator. The loop-filter-less(LPF-less) PLL is proposed to make phase of PLL output carrier signal track t...This paper presents a compact ultra-low-power phase-locked loop (PLL) based binary phase-shift keying(BPSK)demodulator. The loop-filter-less(LPF-less) PLL is proposed to make phase of PLL output carrier signal track the phase of BPSK signal in real time. Thus, the maximum date rate can be significantly extended to the half of the carrier frequency(f_(carrier)) with a very compact size compared to prior PLL-based BPSK demodulators. Furthermore, eliminating all the static power in our LPF-less PLL, the energy efficiency is obviously improved. Fabricated in a 40-nm CMOS process, our prototype occupies 0.0012-mm^(2)core active area, and achieves the maximum data rate of 6.78 Mb/s (f_(carrier)/2) at f_(carrier)of 13.56 MHz. The power consumption and energy efficiency is 4.47 μW and 0.66 pJ/bit at 6.78-Mb/s data rate, respectively.展开更多
BACKGROUND In the treatment of rectal cancer,a temporary loop ileostomy(TLI)is created after low anterior resection to protect bowel function in the postoperative period.Dehydration and kidney failure are significant ...BACKGROUND In the treatment of rectal cancer,a temporary loop ileostomy(TLI)is created after low anterior resection to protect bowel function in the postoperative period.Dehydration and kidney failure are significant potential complications in loop ileostomies.Compared to late closure(3-6 months),early closure(10-14 days)of the TLI may facilitate faster patient recovery and shorter hospital stays.AIM To compare early and late closure of TLIs and demonstrate that early stoma closure can be performed without increasing morbidity.METHODS This study included patients who underwent TLI for rectal cancer,with data collected prospectively between June 2016 and October 2024 and analyzed retrospectively.Patients whose stomas were closed in the late period(3-6 months)between June 2016 and October 2022(group A)were compared with those who underwent early closure(10-14 days)between October 2022 and 2024(group B),with the primary outcome being complication rate and the secondary outcome being quality of life.RESULTS A total of 270 TLIs were created(70.9%).Of these,120(44.4%)were closed in the late period(group A),and 150(55.6%)were closed in the early period(group B).There was no statistically significant difference between group A and group B in terms of demographic and clinicopathological characteristics(P>0.05).Perioperative(anesthesia management,operative time,blood loss,surgical technique)and postoperative findings(anastomotic leak,infection)were similar between the two groups and were not statistically significant(P>0.05).There were no statistically significant differences in complication rates as the primary outcome between the two groups.Quality of life as a secondary outcome was significantly higher in the early closure group(P<0.05).CONCLUSION No statistically significant difference was found between early and late loop ileostomy closure in terms of perioperative and postoperative morbidity.Early closure accelerated patients’psychological and social recovery.展开更多
In response to the complex working conditions of the power grid caused by the high proportion of new energy access,which leads to insufficient output accuracy of the second-order generalized integrator(SOGI)phaselocke...In response to the complex working conditions of the power grid caused by the high proportion of new energy access,which leads to insufficient output accuracy of the second-order generalized integrator(SOGI)phaselocked loop,this article proposes an improved frequency adaptive phase-locked loop structure for SOGI.Firstly,an amplitude compensation branch is introduced to compensate for the SOGI tracking fundamental frequency signal,ensuring the accuracy of the SOGI output orthogonal signal under frequency fluctuation conditions.Secondly,by cascading two adaptive SOGI modules,the suppression capability of low-order harmonics and Direct Current(DC)components has been improved.Finally,the positive and negative sequence separation method of orthogonal signals is introduced to eliminate the influence of unbalanced components on the phase-locked loop.The comparative experiment with the classic SOGI-PLL method shows that the proposed phase-locked loop structure effectively improves the accuracy of power grid synchronization detection under complex working conditions such as harmonic components,unbalanced components,and frequency fluctuations.It can complete frequency detection within 1.5 power frequency cycles,and the detected fundamental frequency positive sequence voltage has a higher sinuosity and harmonic distortion rate within 0.5%.展开更多
Mongolia is a landlocked country with limited infrastructure and high dependence on the Xingang Tianjin port in China for imports. This research examines the potential impacts of establishing a dry port in Zamyn-Uud, ...Mongolia is a landlocked country with limited infrastructure and high dependence on the Xingang Tianjin port in China for imports. This research examines the potential impacts of establishing a dry port in Zamyn-Uud, Mongolia, utilizing a system dynamics modeling approach via Vensim software. The study evaluates transportation time, costs, inflation, and logistics performance index improvements, revealing that the establishment of the dry port can reduce transportation costs and delays significantly while enhancing economic growth. The findings offer actionable insights for policymakers and stakeholders in addressing logistical inefficiencies and fostering sustainable development in landlocked regions.展开更多
In-situ TEM observation was conducted during Ni^(+)&He^(+)dual-beam irradiation to monitor the evolution of dislocation loops accompanied by He bubbles in the Ni-based alloy GH3535.Two distinct evolutions of dislo...In-situ TEM observation was conducted during Ni^(+)&He^(+)dual-beam irradiation to monitor the evolution of dislocation loops accompanied by He bubbles in the Ni-based alloy GH3535.Two distinct evolutions of dislocation loops,driven by residual stresses,were observed within the monitored grains.Hence,molec-ular dynamics(MD)simulations were employed to reveal the effects of stress magnitude and direction on loop evolution,including size,number density,type and variation.The simulations revealed that the presence of compressive stress reduced the formation energy of perfect dislocation loops,thus promoting their formation.Stress state was found to influence the preferential orientation of the loops,and com-pressive stress resulted in a decreased number density of dislocation loops but an increase in their size.This establishes a clear relationship between stress state and magnitude and the evolution of dislocation loops during ion beam irradiation.Additionally,the nature and characteristics of dislocation loops were quantified to explore the effects of He concentrations on their evolution.The higher He concentration not only promotes the nucleation of dislocation loops,leading to their higher number density,but also facil-itates the unfaulting evolution by increasing the stacking fault energy(SFE).Moreover,the accumulation of He in the lower-He-concentration sample led to the growth of dislocation loops in multiple stages,explaining their nearly identical average sizes when compared to the higher-He-concentration sample.展开更多
Aiming at the global design issue of transpiration cooling thermal protection system,a self-driven circulation loop is proposed as the internal coolant flow passage for the transpiration cooling structure to achieve a...Aiming at the global design issue of transpiration cooling thermal protection system,a self-driven circulation loop is proposed as the internal coolant flow passage for the transpiration cooling structure to achieve adaptive cooling.To enhance the universality of this internal cooling pipe design and facilitate its application,numerical studies are conducted on this systemwith four commonly used cooling mediums as coolant.Firstly,the accuracy of the numerical method is verified through an established experimental platform.Then,transient numerical simulations are performed on the flow states of different cooling mediums in the new self-circulation system.Based on the numerical result,the flow,phase change,and heat transfer characteristics of different cooling mediums are analyzed.Differences in fluid velocity and latent heat of phase change result in significant variation in heat exchange capacity among different coolingmediums,with the maximumdifference reaching up to 3 times.Besides,faster circulation speed leads to greater heat transfer capacity,with a maximum of 7600 W/m^(2).Consequently,the operating mechanism and cooling laws of the natural circulation system is further investigated,providing a reference for the practical application of this system.展开更多
With the development of space-based remote sensing and deep space exploration technology,higher standards for temperature stability and uniformity of payloads have been proposed to spacecraft thermal control systems.A...With the development of space-based remote sensing and deep space exploration technology,higher standards for temperature stability and uniformity of payloads have been proposed to spacecraft thermal control systems.As an efficient two-phase heat transfer device with active temperature control capabilities,the loop heat pipe(LHP)can be widely applied in spacecraft thermal control systems to achieve reliable temperature control under various operating modes and complex space thermal environments.This paper analyzes the fundamental theories of thermal switch-controlled,reservoir temperature-controlled,and bypass valve-controlled LHPs.The focus is on the theories and methods of achieving high-precision and high-reliability temperature control via active reservoir temperature control.Novel control techniques in recent years,such as non-condensable gas(NCG)control with a temperature stability of 0.01℃ ,are also briefly introduced as promising approaches to improve LHP performance.The on-orbit performance and characteristics of various LHP temperature control methods are provided and ranked in terms of control precision,energy consumption,complexity,and weight.Thermoelectric cooler(TEC)/electrical heater,as the foundation of reservoir temperature control,can achieve a temperature stability of in space applications under±0.2℃ a wide range of heat load.Microgravity model,control strategy,and operating mode conversion are three optimization directions that would hopefully further expand the application scenario of reservoir temperature control.Specific design principles and challenges for corresponding directions are summarized as guidance for researchers.展开更多
The phase-locked loop(PLL)plays an essential role for synchronizing renewable power generation to the grid.However,as per the grid-code compliance for reactive current support,the PLL output frequency fluctuates signi...The phase-locked loop(PLL)plays an essential role for synchronizing renewable power generation to the grid.However,as per the grid-code compliance for reactive current support,the PLL output frequency fluctuates significantly and exceeds the limitation,which seriously threaten the safe supply of electricity.In this paper,the underlying theoretical mechanism and dominant force behind the maximum PLL frequency deviation are revealed.Accordingly,two feasible approaches are proposed to enhance the PLL frequency stability with validations in experimental results.展开更多
文摘Looped light in a recent sophisticated real three-slit experiment is interpreted as a strong justification of the old theoretical Peano-Hilbert spacetime model of Ord and El Naschie. This in turn entails the existence of extra fractal dimensions and consequently of real dark energy density in full agreement with previous analysis as well as accurate measurements and observations of COBE, WMAP, and the type 1a supernova.
文摘A power flow analysis method for weakly looped distribution systems with PV buses is proposed in this paper. The proposed method is computationally more efficient and more robust compared with the conventional compensation methods. The robustness is achieved by embedding the boundary conditions of loops and PV buses into the Jacobian matrix. The computational efficiency is achieved by the carefully designed factorization of Jacobian matrix. Test results on a 33 bus system are presented.
文摘This study explores the clinical application of the circular wide and deep(looped,broad,and deep buried,LBD)suture technique for scar resection and examines its clinical effectiveness for scar treatment.From June 2017 to March 2019,a total of 68 patients with scars were sutured using LBD technique,and recovery was achieved 24 months postoperatively.In all 68 patients,postoperative scars were slightly evident in two cases of cervical scar,one case of leg scar,and one case of chest scar.In addition,the remaining 62 patients were completely satisfied with the outcome.The LBD suturing technique could provide sustained and stable tension-reducing effects postoperatively and significantly improve scar formation in patients.This method is most applicable to incisions with tension.Therefore,it should be more widely used for clinical scar treatment.
文摘In this investigation, a novel thermally coupled reactor （TCR） containing methyl formate （MF） production in the endothermic side and methanol synthesis in the exothermic side has been investigated. The interesting feature of this TCR is that productive methanol in the exothermic side could be recycled and used as feed of endothermic side for MF synthesis. Other important advantages of the proposed system are high production rates of hydrogen and MF. The configuration consists of two thermally coupled concentric tubular reactors. In these coupled reactors, autothermal system is obtained within the reactor. A steady-state heterogeneous model is used for simulation of the coupled reactor. The proposed model has been utilized to compare the performance of TCR with the conventional methanol reactor （CMR）. Noticeable enhancement can be obtained in the performance of the reactors. The influence of operational parameters is studied on reactor performance. The results show that coupling of these reactions could be feasible and beneficial. Experimental proof-of-concept is required to validate the operation of the novel reactor.
文摘We give a mathematical golden mean distribution based probabilistic confirmation of a recent spectacular experiment with light. The experiment in question is a three-slit variant of the well known two-slit set up of quantum mechanics. The outcome of the sophisticated experiment revealed the looped path of light on the quantum scale and consequently the Peano-Hilbert geometry of spacetime, ergo its fractal-Cantorian nature. The mathematics used here on the other hand is the remarkably simple and insightful golden mean probability distribution known from a famous paradox known in social sciences as the voter paradox.
基金supported by GILO Foundation.This research is in part supported by Korea Drug Development Fund funded by Ministry of Science and ICT,Ministry of Trade,Industry,and Energy,and Ministry of Health and Welfare(RS-2023-00282595,Republic of Korea).
文摘Rheumatoid arthritis(RA)is an autoimmune disease characterized by inflammation and abnormal osteoclast activation,leading to bone destruction.We previously demonstrated that the large extracellular loop(LEL)of Tm4sf19 is important for its function in osteoclast differentiation,and LEL-Fc,a competitive inhibitor of Tm4sf19,effectively suppresses osteoclast multinucleation and prevent bone loss associated with osteoporosis.This study aimed to investigate the role of Tm4sf19 in RA,an inflammatory and abnormal osteoclast disease,using a mouse model of collagen-induced arthritis(CIA).Tm4sf19 expression was observed in macrophages and osteoclasts within the inflamed synovium,and Tm4sf19 expression was increased together with inflammatory genes in the joint bones of CIA-induced mice compared with the sham control group.Inhibition of Tm4sf19 by LEL-Fc demonstrated both preventive and therapeutic effects in a CIA mouse model,reducing the CIA score,swelling,inflammation,cartilage damage,and bone damage.Knockout of Tm4sf19 gene or inhibition of Tm4sf19 activity by LEL-Fc suppressed LPS/IFN-γ-induced TLR4-mediated inflammatory signaling in macrophages.LEL-Fc disrupted not only the interaction between Tm4sf19 and TLR4/MD2,but also the interaction between TLR4 and MD2.μCT analysis showed that LEL-Fc treatment significantly reduced joint bone destruction and bone loss caused by hyperactivated osteoclasts in CIA mice.Taken together,these findings suggest that LELFc may be a potential treatment for RA and RA-induced osteoporosis by simultaneously targeting joint inflammation and bone destruction caused by abnormal osteoclast activation.
基金the University of Bahrain for sponsoring the PhD programme of the first authorEPSRC UK for supporting this research under grants GR/T04502/01 and GR/T04519/01
文摘The aim of this paper is to present the design and experimental validation process for a thermoacoustic looped-tube engine. The design procedure consists of numerical modelling of the system using DELTA EC tool, Design Environment for Low-amplitude ThermoAcousfic Energy Conversion, in particular the effects of mean pressure and regenerator configuration on the pressure amplitude and acoustic power generated. This is followed by the construction of a practical engine system equipped with a ceramic regenerator - a substrate used in auto- motive catalytic converters with fine square channels. The preliminary testing results are obtained and compared with the simulations in detail.The measurement results agree very well on the qualitative level and are reasonably close in the quantitative sense.
基金Science Foundation for Distinguished Young Scholars 2020-JCJQ-ZQ-042 Intelligent and Bionic Spacecraft Thermal Control Technology Inspired by Tree Sap Transport Principle.
文摘As space technology advances,thermal control systems must effectively collect and dissipate heat from distributed,multi-source environments.Loop heat pipe is a highly reliable two-phase heat transfer component,but it has several limitations when addressing multi-source heat dissipation.Inspired by the transport and heat dissipation system of plants,large trees achieve stable and efficient liquid supply under the influence of two driving forces:capillary force during transpiration in the leaves(pull)and root pressure generated by osmotic pressure in the roots(push).The root pressure provides an effective liquid supply with a driving force exceeding 2 MPa,far greater than the driving force in conventional capillary-pumped two-phase loops.Research has shown that osmotic heat pipes offer a powerful driving force,and combining osmotic pressure with capillary force has significant advantages.Therefore,this paper designs a multi-evaporator,dual-drive two-phase loop,using both osmotic pressure and capillary force to solve the multi-source heat dissipation challenge.First,a transmembrane water flux model for the osmotic pressure-driven device was established to predict the maximum heat transfer capacity of the dual-drive two-phase loop.Then,an experimental setup for a multi-evaporator“osmotic pressure+capillary force”dual-drive two-phase loop was constructed,capable of transferring at least 235 W of power under a reverse gravity condition of 20 m.The study also analyzed the effects of reverse gravity height,heat load distribution among the three evaporators,startup sequence,and varying branch resistances on the performance of the dual-drive two-phase loop.
基金supported by the National Natural Science Foundation of China under grant 62222409 and 62174153by Key Research Program of Frontier Sciences, CAS, under grant ZDBS-LY-JSC008。
文摘This paper presents a compact ultra-low-power phase-locked loop (PLL) based binary phase-shift keying(BPSK)demodulator. The loop-filter-less(LPF-less) PLL is proposed to make phase of PLL output carrier signal track the phase of BPSK signal in real time. Thus, the maximum date rate can be significantly extended to the half of the carrier frequency(f_(carrier)) with a very compact size compared to prior PLL-based BPSK demodulators. Furthermore, eliminating all the static power in our LPF-less PLL, the energy efficiency is obviously improved. Fabricated in a 40-nm CMOS process, our prototype occupies 0.0012-mm^(2)core active area, and achieves the maximum data rate of 6.78 Mb/s (f_(carrier)/2) at f_(carrier)of 13.56 MHz. The power consumption and energy efficiency is 4.47 μW and 0.66 pJ/bit at 6.78-Mb/s data rate, respectively.
文摘BACKGROUND In the treatment of rectal cancer,a temporary loop ileostomy(TLI)is created after low anterior resection to protect bowel function in the postoperative period.Dehydration and kidney failure are significant potential complications in loop ileostomies.Compared to late closure(3-6 months),early closure(10-14 days)of the TLI may facilitate faster patient recovery and shorter hospital stays.AIM To compare early and late closure of TLIs and demonstrate that early stoma closure can be performed without increasing morbidity.METHODS This study included patients who underwent TLI for rectal cancer,with data collected prospectively between June 2016 and October 2024 and analyzed retrospectively.Patients whose stomas were closed in the late period(3-6 months)between June 2016 and October 2022(group A)were compared with those who underwent early closure(10-14 days)between October 2022 and 2024(group B),with the primary outcome being complication rate and the secondary outcome being quality of life.RESULTS A total of 270 TLIs were created(70.9%).Of these,120(44.4%)were closed in the late period(group A),and 150(55.6%)were closed in the early period(group B).There was no statistically significant difference between group A and group B in terms of demographic and clinicopathological characteristics(P>0.05).Perioperative(anesthesia management,operative time,blood loss,surgical technique)and postoperative findings(anastomotic leak,infection)were similar between the two groups and were not statistically significant(P>0.05).There were no statistically significant differences in complication rates as the primary outcome between the two groups.Quality of life as a secondary outcome was significantly higher in the early closure group(P<0.05).CONCLUSION No statistically significant difference was found between early and late loop ileostomy closure in terms of perioperative and postoperative morbidity.Early closure accelerated patients’psychological and social recovery.
基金the Yunnan Engineering Research Center Innovation Ability Construction and Enhancement Projects[2023-XMDJ-00617107]Natural Science Foundation of Yunnan Province[202401AS070646]Natural Science Foundation of Jiangxi Provincial[20232BAB214038].
文摘Despite progress in suppressing polysulfide shuttling,this challenge persists in lithium-sulfur battery commercialization.While existing strategies emphasize polysulfide adsorption and catalytic conversion,the critical role of diffusion kinetics in conversion–deposition processes remains underexplored.We design an MXene-based array architecture integrating 2D structural advantages and strong polysulfide affinity to regulate diffusion pathways.Combined experimental and multiscale computational studies reveal diffusion-mediated conversion-deposition dynamics.The sodium alginate-constructed MXene array enables three synergistic mechanisms:(1)Enhanced ion/electron delocalization reduces diffusion barriers,(2)Continuous ion transport channels facilitate charge transfer,and(3)Exposed polar surfaces promote polysulfide aggregation/conversion.Synchrotron X-ray tomography coupled with comprehensive electrochemical analyses reveals distinct mechanistic differences between conversion and deposition processes arising from diffusion heterogeneity.In situ characterization techniques combined with DFT simulation calculations demonstrate that diffusion kinetics exerts differential regulatory effects on these coupled electrochemical processes,exhibiting particular sensitivity toward the deposition mechanism.This work provides fundamental insights that reshape our understanding of diffusion-mediated phase transformation in complex multi-step electrochemical systems,offering new perspectives for advanced electrode architecture design in next-generation energy storage technologies.
基金supported by the Science and Technology Project of China Southern Power Grid Co.,Ltd.(Grant No.ZBKJXM20232471)the National Key R&D Program of China(Grant No.2021YFB1600200)the Innovation Capability Support Program of Shaanxi(Grant No.2022KXJ-144)。
文摘In response to the complex working conditions of the power grid caused by the high proportion of new energy access,which leads to insufficient output accuracy of the second-order generalized integrator(SOGI)phaselocked loop,this article proposes an improved frequency adaptive phase-locked loop structure for SOGI.Firstly,an amplitude compensation branch is introduced to compensate for the SOGI tracking fundamental frequency signal,ensuring the accuracy of the SOGI output orthogonal signal under frequency fluctuation conditions.Secondly,by cascading two adaptive SOGI modules,the suppression capability of low-order harmonics and Direct Current(DC)components has been improved.Finally,the positive and negative sequence separation method of orthogonal signals is introduced to eliminate the influence of unbalanced components on the phase-locked loop.The comparative experiment with the classic SOGI-PLL method shows that the proposed phase-locked loop structure effectively improves the accuracy of power grid synchronization detection under complex working conditions such as harmonic components,unbalanced components,and frequency fluctuations.It can complete frequency detection within 1.5 power frequency cycles,and the detected fundamental frequency positive sequence voltage has a higher sinuosity and harmonic distortion rate within 0.5%.
文摘Mongolia is a landlocked country with limited infrastructure and high dependence on the Xingang Tianjin port in China for imports. This research examines the potential impacts of establishing a dry port in Zamyn-Uud, Mongolia, utilizing a system dynamics modeling approach via Vensim software. The study evaluates transportation time, costs, inflation, and logistics performance index improvements, revealing that the establishment of the dry port can reduce transportation costs and delays significantly while enhancing economic growth. The findings offer actionable insights for policymakers and stakeholders in addressing logistical inefficiencies and fostering sustainable development in landlocked regions.
基金supported by the National Natural Science Foundation of China(Nos.U2341261 and 12375280)the Young Potential Program of Shanghai Institute of Applied Physics,Chinese Academy of Sciences(No.YXJH-2022002)the National MCF Energy R&D Program(No.2022YFE03110000).
文摘In-situ TEM observation was conducted during Ni^(+)&He^(+)dual-beam irradiation to monitor the evolution of dislocation loops accompanied by He bubbles in the Ni-based alloy GH3535.Two distinct evolutions of dislocation loops,driven by residual stresses,were observed within the monitored grains.Hence,molec-ular dynamics(MD)simulations were employed to reveal the effects of stress magnitude and direction on loop evolution,including size,number density,type and variation.The simulations revealed that the presence of compressive stress reduced the formation energy of perfect dislocation loops,thus promoting their formation.Stress state was found to influence the preferential orientation of the loops,and com-pressive stress resulted in a decreased number density of dislocation loops but an increase in their size.This establishes a clear relationship between stress state and magnitude and the evolution of dislocation loops during ion beam irradiation.Additionally,the nature and characteristics of dislocation loops were quantified to explore the effects of He concentrations on their evolution.The higher He concentration not only promotes the nucleation of dislocation loops,leading to their higher number density,but also facil-itates the unfaulting evolution by increasing the stacking fault energy(SFE).Moreover,the accumulation of He in the lower-He-concentration sample led to the growth of dislocation loops in multiple stages,explaining their nearly identical average sizes when compared to the higher-He-concentration sample.
基金funded by Fei He,National Natural Science Foundation of China(contract no.52376154)Anhui Provincial Natural Science Foundation(contract no.2308085J21).
文摘Aiming at the global design issue of transpiration cooling thermal protection system,a self-driven circulation loop is proposed as the internal coolant flow passage for the transpiration cooling structure to achieve adaptive cooling.To enhance the universality of this internal cooling pipe design and facilitate its application,numerical studies are conducted on this systemwith four commonly used cooling mediums as coolant.Firstly,the accuracy of the numerical method is verified through an established experimental platform.Then,transient numerical simulations are performed on the flow states of different cooling mediums in the new self-circulation system.Based on the numerical result,the flow,phase change,and heat transfer characteristics of different cooling mediums are analyzed.Differences in fluid velocity and latent heat of phase change result in significant variation in heat exchange capacity among different coolingmediums,with the maximumdifference reaching up to 3 times.Besides,faster circulation speed leads to greater heat transfer capacity,with a maximum of 7600 W/m^(2).Consequently,the operating mechanism and cooling laws of the natural circulation system is further investigated,providing a reference for the practical application of this system.
基金funded by National Outstanding Youth Foundation of China,grant number 2020-JCJQ-ZQ-042.
文摘With the development of space-based remote sensing and deep space exploration technology,higher standards for temperature stability and uniformity of payloads have been proposed to spacecraft thermal control systems.As an efficient two-phase heat transfer device with active temperature control capabilities,the loop heat pipe(LHP)can be widely applied in spacecraft thermal control systems to achieve reliable temperature control under various operating modes and complex space thermal environments.This paper analyzes the fundamental theories of thermal switch-controlled,reservoir temperature-controlled,and bypass valve-controlled LHPs.The focus is on the theories and methods of achieving high-precision and high-reliability temperature control via active reservoir temperature control.Novel control techniques in recent years,such as non-condensable gas(NCG)control with a temperature stability of 0.01℃ ,are also briefly introduced as promising approaches to improve LHP performance.The on-orbit performance and characteristics of various LHP temperature control methods are provided and ranked in terms of control precision,energy consumption,complexity,and weight.Thermoelectric cooler(TEC)/electrical heater,as the foundation of reservoir temperature control,can achieve a temperature stability of in space applications under±0.2℃ a wide range of heat load.Microgravity model,control strategy,and operating mode conversion are three optimization directions that would hopefully further expand the application scenario of reservoir temperature control.Specific design principles and challenges for corresponding directions are summarized as guidance for researchers.
基金supported by the National Natural Science Foundation of China under Grant 52407069the Science and Technology Project of Zhejiang Province under Grant 2024C01254the China Postdoctoral Science Foundation under Grant 2024T170766 and 2024M762824。
文摘The phase-locked loop(PLL)plays an essential role for synchronizing renewable power generation to the grid.However,as per the grid-code compliance for reactive current support,the PLL output frequency fluctuates significantly and exceeds the limitation,which seriously threaten the safe supply of electricity.In this paper,the underlying theoretical mechanism and dominant force behind the maximum PLL frequency deviation are revealed.Accordingly,two feasible approaches are proposed to enhance the PLL frequency stability with validations in experimental results.
