To enhance power flow regulation in scenarios involving large-scale renewable energy transmission via high-voltage direct current(HVDC)links and multi-infeed DC systems in load-center regions,this paper proposes a hyb...To enhance power flow regulation in scenarios involving large-scale renewable energy transmission via high-voltage direct current(HVDC)links and multi-infeed DC systems in load-center regions,this paper proposes a hybrid modular multilevel converter–capacitor-commutated line-commutated converter(MMC-CLCC)HVDC transmission system and its corresponding control strategy.First,the system topology is constructed,and a submodule configuration method for the MMC—combining full-bridge submodules(FBSMs)and half-bridge submodules(HBSMs)—is proposed to enable direct power flow reversal.Second,a hierarchical control strategy is introduced,includingMMCvoltage control,CLCC current control,and a coordinationmechanism,along with the derivation of the hybrid system’s power flow reversal characteristics.Third,leveraging the CLCC’s fast current regulation and theMMC’s negative voltage control capability,a coordinated power flow reversal control strategy is developed.Finally,an 800 kV MMC-CLCC hybrid HVDC system is modeled in PSCAD/EMTDC to validate the power flow reversal performance under a high proportion of full-bridge submodule configuration.Results demonstrate that the proposed control strategy enables rapid(1-s transition)and smooth switching of bidirectional power flow without modifying the structure of primary equipment:the transient fluctuation ofDC voltage from the rated value(UdcN)to themaximumreverse voltage(-kUdcN)is less than 5%;the DC current strictly follows the preset characteristic curve with a deviation of≤3%;the active power reverses continuously,and the system maintains stable operation throughout the reversal process.展开更多
Cancer multidrug resistance(MDR)impairs the therapeutic efficacy of various chemotherapeutics.Novel approaches,particularly the development of MDR reversal agents,are critically needed to address this challenge.This s...Cancer multidrug resistance(MDR)impairs the therapeutic efficacy of various chemotherapeutics.Novel approaches,particularly the development of MDR reversal agents,are critically needed to address this challenge.This study demonstrates that tenacissoside I(TI),a compound isolated from Marsdenia tenacissima(Roxb.)Wight et Arn,traditionally used in clinical practice as an ethnic medicine for cancer treatment,exhibits significant MDR reversal effects in ABCB1-mediated MDR cancer cells.TI reversed the resistance of SW620/AD300 and KBV200 cells to doxorubicin(DOX)and paclitaxel(PAC)by downregulating ABCB1 expression and reducing ABCB1 drug transport function.Mechanistically,protein arginine methyltransferase 1(PRMT1),whose expression correlates with poor prognosis and shows positive association with both ABCB1 and EGFR expressions in tumor tissues,was differentially expressed in TI-treated SW620/AD300 cells.SW620/AD300 and KBV200 cells exhibited elevated levels of EGFR asymmetric dimethylarginine(aDMA)and enhanced PRMT1-EGFR interaction compared to their parental cells.Moreover,TI-induced PRMT1 downregulation impaired PRMT1-mediated aDMA of EGFR,PRMT1-EGFR interaction,and EGFR downstream signaling in SW620/AD300 and KBV200 cells.These effects were significantly reversed by PRMT1 overexpression.Additionally,TI demonstrated resistance reversal to PAC in xenograft models without detectable toxicities.This study establishes TI's MDR reversal effect in ABCB1-mediated MDR human cancer cells through inhibition of PRMT1-mediated aDMA of EGFR,suggesting TI's potential as an MDR modulator for improving chemotherapy outcomes.展开更多
Patients admitted with prediabetes and atrial fibrillation are at high risk for major adverse cardiac or cerebrovascular events independent of confounding variables.The shared pathophysiology between these three serio...Patients admitted with prediabetes and atrial fibrillation are at high risk for major adverse cardiac or cerebrovascular events independent of confounding variables.The shared pathophysiology between these three serious but common diseases and their association with atherosclerotic cardiovascular risk factors establish a vicious circle culminating in high atherogenicity.Because of that,it is of paramount importance to perform risk stratification of patients with prediabetes to define phenotypes that benefit from various interventions.Furthermore,stress hyperglycemia assessment of hospitalized patients and consensus on the definition of prediabetes is vital.The roles lifestyle and metformin play in prediabetes are well established.However,the role of glucagon-like peptide agonists and metabolic surgery is less clear.Prediabetes is considered an intermediate between normoglycemia and diabetes along the blood glucose continuum.One billion people are expected to suffer from prediabetes by the year 2045.Therefore,realworld randomized controlled trials to assess major adverse cardiac or cerebrovascular event risk reduction and reversal/prevention of type 2 diabetes among patients are needed to determine the proper interventions.展开更多
Previous studies have indicated a global reversal of near-surface wind speeds from a declining trend to an increasing trend around 2010;however,it remains unclear whether upper-air wind speeds exhibit a similar revers...Previous studies have indicated a global reversal of near-surface wind speeds from a declining trend to an increasing trend around 2010;however,it remains unclear whether upper-air wind speeds exhibit a similar reversal.This study evaluates reanalysis products using surface and radiosonde observations to analyze upper-air wind speed variations in the Northern Hemisphere,focusing on their seasonal and latitudinal differences.Results demonstrate that JRA-55 effectively captures wind speed variations in the Northern Hemisphere.Notably,upper-air wind speeds over land experienced a reversal in winter 2010 with significant latitudinal differences.The trend reversal of upper wind speed between the midlatitudes and subtropics presents a dipole pattern.From 1990 to 2010,upper-air wind speeds in the midlatitudes(40°-70°N)significantly declined,while the subtropical zone(20°-40°N)displayed an opposite trend.However,during 2010-2020,wind speeds in the midlatitudes shifted to a significant positive trend,whereas the subtropics experienced a significant negative trend.The variations in Northern Hemisphere winter wind speeds can be attributed to changes in low-level baroclinicity driven by tropical diabatic heating and midlatitude transient eddy feedback.Enhanced diabatic heating and weakened eddy feedback during 1990-2010 contributed to reduced wind speeds in the midlatitudes and increased speeds in the subtropics,while reduced diabatic heating and strengthened eddy feedback during 2010-2020 resulted in increased wind speeds in the midlatitudes and decreased speeds in the subtropics.The reversal of upper-air wind speeds could affect surface wind speeds by downward momentum transfer,which could contribute to the reversal of surface wind speeds.展开更多
In high-speed multiuser Time Reversal(TR)downlink systems,the transmission rate is degraded due to the presence of severe inter-user and inter-symbol interference.Moreover,maximizing the weighted sum rate in such syst...In high-speed multiuser Time Reversal(TR)downlink systems,the transmission rate is degraded due to the presence of severe inter-user and inter-symbol interference.Moreover,maximizing the weighted sum rate in such systems is a critical objective,since the weighting factors represent the priority of different users in different applications.However,it faces significant challenges as it is an NP-hard and non-convex problem.In order to suppress these interferences and maximize the weighted sum rate,in this paper we present a novel approach for the joint design of the pre-filters.The proposed method applies successive convex approximation to transform the original problem into a Second-Order Cone Programming(SOCP)problem.Then,a low-complexity iterative algorithm is provided to effectively solve the resulting SOCP problem.According to the simulation results,the proposed method reaches a local optimum within a few iterations and demonstrates superior performance in terms of weighted sum rate compared to the current algorithm.展开更多
The effective intracellular accumulation of doxorubicin(DOX)is crucial for improving antitumor efficacy,which is severely impeded by limited drug penetration,uncontrollable drug release,and drug resistance.In this stu...The effective intracellular accumulation of doxorubicin(DOX)is crucial for improving antitumor efficacy,which is severely impeded by limited drug penetration,uncontrollable drug release,and drug resistance.In this study,a thermal-deformative polymer embedding ultrasmall ceria(CeO_(2))was rationally designed for deep tumor drug shuttling and hypoxia reversal to improve chemotherapy.Structurally,the CeO_(2)nanozyme was covalently grafted with a polymer of p(NIPAM-co-AM)that could sharply shrink for DOX loading,which was consolidated with polydopamine(PDA)film encapsulation.Thereafter,a tumor penetration guide of apolipoprotein A-I(apoA-I)conjugated iRGD peptide(apoA-I-iRGD)was further decorated onto the PDA shell via Michael addition for preparing CeO_(2)P/DOX@iAPDA.With the aid of apoA-I-iRGD,CeO_(2)P/DOX@iAPDA penetrated both the tumor spheroids(∼78μm)and the tumors of the mouse model deeply.After internalization by tumor cells and triggering by low pH in lysosomes,rapid DOX release was achieved by peeling off the PDA shell and thermosensitive deformation of p(NIPAM-co-AM).CeO_(2)P/DOX@iAPDA provided 66.4%tumor suppression in 4T1-derived tumor spheroids and 63.2%in 4T1-tumorbearing mice,respectively.Preliminary mechanistic research involving western blotting and immunohistochemistry revealed that CeO_(2)P/DOX@iAPDA reversed resistance through the through HIF-1α-P-gp/lipid axis.Collectively,this study intelligently integrated CeO_(2)nanozymes,temperature-sensitive polymers,and imitated biochemical modifications to improve chemotherapy for breast cancer.展开更多
BACKGROUND There is an increased maturation of laparoscopic intracorporeal anastomosis techniques.However,research on its application for small bowel stoma reversal in patients with Crohn's disease(CD)is limited.T...BACKGROUND There is an increased maturation of laparoscopic intracorporeal anastomosis techniques.However,research on its application for small bowel stoma reversal in patients with Crohn's disease(CD)is limited.Therefore,in this study,we compared the perioperative outcomes between laparoscopic intracorporeal ileostomy reversal(LIIR)and open ileostomy reversal(OIR).AIM To compare the safety,feasibility,bowel function recovery,and short-and longterm LIIR and OIR outcomes in patients with CD.METHODS This study included patients who underwent ileal reversal for CD between January 2021 and January 2023 at our institution.The baseline data,postoperative recovery,and complication indicators were retrospectively analyzed.Logistic regression analysis was conducted to explore factors that significantly influenced the development of enteral nutrition intolerance-related symptoms.RESULTS Notably,15 of the 45 patients in this study underwent OIR,and the remaining 30 received LIIR.Notably,no statistically significant differences were found between the two groups regarding clinical baseline characteristics,operation time,intraoperative hemorrhage,anastomotic site,enterolysis range,first postoperative flatus,postoperative complications,reoperation rate,or incidence of postoperative enteral nutrition intolerance.Compared with the OIR group,the LIIR group had a shorter postoperative hospital stay(P=0.045),lower incidence of enteral nutrition intolerance symptoms(P=0.019),and earlier postoperative total enteral nutrition initiation(P=0.033);however,it incurred higher total hospital costs(P=0.038).Furthermore,multivariate logistic regression analysis revealed that the duration of surgery and anastomotic technique were independent risk factors for postoperative symptoms of enteral nutrition intolerance(P<0.05).CONCLUSION Laparoscopic intracorporeal anastomosis for ileostomy reversal is safe and feasible.Patients who underwent this technique demonstrated improved tolerance to postoperative enteral nutrition and quicker resumption of total enteral nutrition.展开更多
In this editorial,we comment on an article by Liu et al.We focus specifically on the novel use of laparoscopic intracorporeal anastomosis(LIA)compared with open ileostomy reversal in patients with Crohn’s disease(CD)...In this editorial,we comment on an article by Liu et al.We focus specifically on the novel use of laparoscopic intracorporeal anastomosis(LIA)compared with open ileostomy reversal in patients with Crohn’s disease(CD),which is an innovative approach for improving postoperative outcomes and accelerating recovery in ileostomy reversal procedures.This study also highlights the limitations of the conventional open surgical technique,which is associated with higher rates of feeding intolerance,prolonged hospital stays,and delayed initiation of enteral nutrition.The chronic and recurrent nature of CD and the challenges posed by traditional surgical methods are issues addressed by LIA,which offers a minimally invasive approach that reduces surgical trauma,shortens recovery time,and improves tolerance to enteral nutrition,thereby enhancing postoperative outcomes.However,while LIA shows great promise,further prospective multicenter trials are needed to validate these findings and assess their broader application in other surgical scenarios.Overall,LIA represents a significant advancement in minimally invasive surgery for CD and has the potential to become the preferred standard approach for ileostomy reversal in patients requiring bowel reanastomosis.展开更多
Time-reversal symmetry(TRS)breaking induced dissipationless topological phonon edge modes provide an unprecedented way to manipulate phonon transport.However,the effect of TRS breaking on the transport properties of b...Time-reversal symmetry(TRS)breaking induced dissipationless topological phonon edge modes provide an unprecedented way to manipulate phonon transport.However,the effect of TRS breaking on the transport properties of bulk phonon modes is still unclear.In this work,we assess the effect of local TRS-breaking domains on the transport properties of bulk phonon modes in a two-dimensional(2D)hexagonal phononic lattice model.The results show that bulk phonon modes can be strongly scattered by local TRS breaking owing to the shift of the local phonon band gap,which results in significant suppression of phonon transmission.Moreover,we show that the aperiodic distribution of local TRS-breaking domains can induce phonon Anderson localization,and the localization length can be effectively tuned by the strength of TRS breaking.Our study suggests that TRS breaking can not only be used to construct dissipationless topological phonon edge states,but also be used to block the transmission of bulk phonon modes by carefully controlling the size and distribution of TRS-breaking domains.Such results provide a highly alternative way for manipulating energy flux at the nanoscale.展开更多
In recent years,the network public opinion reversal governance events have occurred frequently.Over time,the repeated truth of the matter will not only weaken the rational judgment of the public to a certain extent,so...In recent years,the network public opinion reversal governance events have occurred frequently.Over time,the repeated truth of the matter will not only weaken the rational judgment of the public to a certain extent,so that its negative emotions accumulate,but also have a serious impact on the credibility of the media and the government,and may even further intensify social contradictions.Therefore,in the face of such a complex online public opinion space,accurately identifying the truth behind the incident and how to carry out the reversal of online public opinion governance is particularly critical.And blockchain technology,with its advantages of decentralization and immutable information,provides new technical support for the network public opinion reversal governance.Based on this,this paper gives an overview and analysis of blockchain technology and network public opinion reversal,and on this basis introduces the network public opinion reversal governance mechanism based on blockchain technology,aiming to further optimize the network public opinion reversal governance process,for reference only.展开更多
Aim To analyze the transient speciality of nonlinear, anisotropic, AC+DC coupling electric field, and to compare the withstand voltage strength of different insulation structures. Methods The transient process o...Aim To analyze the transient speciality of nonlinear, anisotropic, AC+DC coupling electric field, and to compare the withstand voltage strength of different insulation structures. Methods The transient process of polarity reversal is analyzed, considering the anisotropic property of oil immersed press board, a new finite element model based on Galerkin method is presented and verified. The model developed is applied to calculate the electric field distribution in four typical winding end structures of the converter transformer. Results\ The whole ring structure possesses the best insulation characteristics. Conclusion\ By introducing reasonable insulation components, insulation strength with the same surrounding sizes can be improved more than 30%.展开更多
In the present work,the magnetization reversal behavior for the melt spinning(Nd_(0.8)Ce_(0.2))_(2)Fe_(12)Co_(2-x)Zr_(x)B(x=0,0.5)permanent alloys with high coercivity was investigated by analyzing the hysteresis curv...In the present work,the magnetization reversal behavior for the melt spinning(Nd_(0.8)Ce_(0.2))_(2)Fe_(12)Co_(2-x)Zr_(x)B(x=0,0.5)permanent alloys with high coercivity was investigated by analyzing the hysteresis curves and the recoil loops.Compared to the Zr-free alloy,the Zr-doped sample obtains higher magnetic properties:coercivity of H_(cj)=650.5 kA·m^(-1),squareness of H_(k)/H_(cj)=0.76 and maximum energy product of(BH)_(max)=131.0 kJ·m^(-3).The first-order reversal curves(FORCs)analysis was taken to identify optimal conditions of exchange coupling for the Zr-free and Zr-doped alloys.The coercivity mechanism of theα-Fe/Nd_(2)Fe_(14)B nanocomposite alloys was analyzed by the angular dependence of the coercive field as measured for the Zr-doped sample.The results show that the magnetic reverse process of the Zr-doped sample can be explained by the pinning model.展开更多
This paper presents a detailed analysis of the effects of noise (reverberation) on the focusing performance of de-composition of the time reversal operator (DORT) in a noise-limited case and in a reverberation-limited...This paper presents a detailed analysis of the effects of noise (reverberation) on the focusing performance of de-composition of the time reversal operator (DORT) in a noise-limited case and in a reverberation-limited case, respectively. Quantitative results obtained from simulations and experiments are presented. The results show the DORT method can be effi-ciently applied to target detection with enough source level to yield significant backscatter. For a target placed on the bottom, the influence of the reverberation on the focusing performance is slight. However, distinguishing between a target and constant backscattering returning from strong local clutter on the bottom (false alarms) needs further research.展开更多
An efficient hybrid time reversal（TR） imaging method based on signal subspace and noise subspace is proposed for electromagnetic superresolution detecting and imaging. First, the locations of targets are estimated b...An efficient hybrid time reversal（TR） imaging method based on signal subspace and noise subspace is proposed for electromagnetic superresolution detecting and imaging. First, the locations of targets are estimated by the transmitting-mode decomposition of the TR operator（DORT） method employing the signal subspace. Then, the TR multiple signal classification（TR-MUSIC）method employing the noise subspace is used in the estimated target area to get the superresolution imaging of targets. Two examples with homogeneous and inhomogeneous background mediums are considered, respectively. The results show that the proposed hybrid method has advantages in CPU time and memory cost because of the combination of rough and fine imaging.展开更多
In this paper, a new method of time reversal for defect diagnosis of concealed structure has been proposed based on the detecting technique of structure acoustic wave and the theory of time reversal. The time reversal...In this paper, a new method of time reversal for defect diagnosis of concealed structure has been proposed based on the detecting technique of structure acoustic wave and the theory of time reversal. The time reversal recurrence formula for detecting the acoustic wave speed constitution of concealed structures with bilevel asynchronous test has been established. The wave speed constitution can be reconstructed in 2 D graticule form by means of this method. The result of model test shows the method is valid.展开更多
Perpendicular synthetic-antiferromagnet(p-SAF) has broad applications in spin-transfer-torque magnetic random access memory and magnetic sensors. In this study, the p-SAF films consisting of (Co/Ni)3]/Ir(tIr)/[(Ni/Co)...Perpendicular synthetic-antiferromagnet(p-SAF) has broad applications in spin-transfer-torque magnetic random access memory and magnetic sensors. In this study, the p-SAF films consisting of (Co/Ni)3]/Ir(tIr)/[(Ni/Co)3are fabricated by magnetron sputtering technology. We study the domain structure and switching field distribution in p-SAF by changing the thickness of the infrared space layer. The strongest exchange coupling field(Hex) is observed when the thickness of Ir layer(tIr) is 0.7 nm and becoming weak according to the Ruderman–Kittel–Kasuya–Yosida-type coupling at 1.05 nm,2.1 nm, 4.55 nm, and 4.9 nm in sequence. Furthermore, the domain switching process between the upper Co/Ni stack and the bottom Co/Ni stack is different because of the antiferromagnet coupling. Compared with ferromagnet coupling films, the antiferromagnet samples possess three irreversible reversal regions in the first-order reversal curve distribution.With tIrincreasing, these irreversible reversal regions become denser and smaller. The results from this study will help us understand the details of the magnetization reversal process in the p-SAF.展开更多
The electromagnetic time-reversal(TR)technique has the characteristics of spatiotemporal focusing in a time-reversal cavity(TRC),which can be used for pulse compression,thus forming an electromagnetic pulse with high ...The electromagnetic time-reversal(TR)technique has the characteristics of spatiotemporal focusing in a time-reversal cavity(TRC),which can be used for pulse compression,thus forming an electromagnetic pulse with high peak power.A time-reversed pulse-compression method in a single channel has high pulse compression gain.However,single channel pulse compression can only generate limited gain.This paper proposes a novel TR power-combination method in a multichannel TRC to obtain higher peak power based on TR pulse-compression theory.First,the TR power-combination model is given,and the crosstalk properties of the associated channel and the influence of the reversal performance are studied.Then,the power-combination performances for the TR pulse compression,such as combined signal to noise ratio(SNR)and combined compression gain,are analyzed by numerical simulation and experimental methods.The results show that the proposed method has obvious advantages over pulse-compression methods using a single channel cavity,and is more convenient for power combination.展开更多
During 1979–2015, the intensity of the Siberian high(SH) in November and December–January(DJ) is frequently shown to have an out-of-phase relationship, which is accompanied by opposite surface air temperature and ci...During 1979–2015, the intensity of the Siberian high(SH) in November and December–January(DJ) is frequently shown to have an out-of-phase relationship, which is accompanied by opposite surface air temperature and circulation anomalies.Further analyses indicate that the autumn Arctic sea ice is important for the phase reversal of the SH. There is a significantly positive(negative) correlation between the November(DJ) SH and the September sea ice area(SIA) anomalies. It is suggested that the reduction of autumn SIA induces anomalous upward surface turbulent heat flux(SHF), which can persist into November, especially over the Barents Sea. Consequently, the enhanced eddy energy and wave activity flux are transported to mid and high latitudes. This will then benefit the development of the storm track in northeastern Europe. Conversely, when downward SHF anomalies prevail in DJ, the decreased heat flux and suppressed eddy energy hinder the growth of the storm track during DJ over the Barents Sea and Europe. Through the eddy–mean flow interaction, the strengthened(weakened)storm track activities induce decreased(increased) Ural blockings and accelerated(decelerated) westerlies, which makes the cold air from the Arctic inhibited(transported) over the Siberian area. Therefore, a weaker(stronger) SH in November(DJ) occurs downstream. Moreover, anomalously large snowfall may intensify the SH in DJ rather than in November. The ensemble-mean results from the CMIP5 historical simulations further confirm these connections. The different responses to Arctic sea ice anomalies in early and middle winter set this study apart from earlier ones.展开更多
基金supported by Science and Technology Project of the headquarters of the State Grid Corporation of China(No.5500-202324492A-3-2-ZN).
文摘To enhance power flow regulation in scenarios involving large-scale renewable energy transmission via high-voltage direct current(HVDC)links and multi-infeed DC systems in load-center regions,this paper proposes a hybrid modular multilevel converter–capacitor-commutated line-commutated converter(MMC-CLCC)HVDC transmission system and its corresponding control strategy.First,the system topology is constructed,and a submodule configuration method for the MMC—combining full-bridge submodules(FBSMs)and half-bridge submodules(HBSMs)—is proposed to enable direct power flow reversal.Second,a hierarchical control strategy is introduced,includingMMCvoltage control,CLCC current control,and a coordinationmechanism,along with the derivation of the hybrid system’s power flow reversal characteristics.Third,leveraging the CLCC’s fast current regulation and theMMC’s negative voltage control capability,a coordinated power flow reversal control strategy is developed.Finally,an 800 kV MMC-CLCC hybrid HVDC system is modeled in PSCAD/EMTDC to validate the power flow reversal performance under a high proportion of full-bridge submodule configuration.Results demonstrate that the proposed control strategy enables rapid(1-s transition)and smooth switching of bidirectional power flow without modifying the structure of primary equipment:the transient fluctuation ofDC voltage from the rated value(UdcN)to themaximumreverse voltage(-kUdcN)is less than 5%;the DC current strictly follows the preset characteristic curve with a deviation of≤3%;the active power reverses continuously,and the system maintains stable operation throughout the reversal process.
基金supported by the National Natural Science Foundation of China(Nos.82274211 and 82474190)the Natural Science Foundation of Tianjin(Nos.24JCZDJC00120 and 24PTLYHZ00280)Liaoning Provincial Department of Education Basic Research Projects for Higher Education Institutions(No.LJ212510163021)。
文摘Cancer multidrug resistance(MDR)impairs the therapeutic efficacy of various chemotherapeutics.Novel approaches,particularly the development of MDR reversal agents,are critically needed to address this challenge.This study demonstrates that tenacissoside I(TI),a compound isolated from Marsdenia tenacissima(Roxb.)Wight et Arn,traditionally used in clinical practice as an ethnic medicine for cancer treatment,exhibits significant MDR reversal effects in ABCB1-mediated MDR cancer cells.TI reversed the resistance of SW620/AD300 and KBV200 cells to doxorubicin(DOX)and paclitaxel(PAC)by downregulating ABCB1 expression and reducing ABCB1 drug transport function.Mechanistically,protein arginine methyltransferase 1(PRMT1),whose expression correlates with poor prognosis and shows positive association with both ABCB1 and EGFR expressions in tumor tissues,was differentially expressed in TI-treated SW620/AD300 cells.SW620/AD300 and KBV200 cells exhibited elevated levels of EGFR asymmetric dimethylarginine(aDMA)and enhanced PRMT1-EGFR interaction compared to their parental cells.Moreover,TI-induced PRMT1 downregulation impaired PRMT1-mediated aDMA of EGFR,PRMT1-EGFR interaction,and EGFR downstream signaling in SW620/AD300 and KBV200 cells.These effects were significantly reversed by PRMT1 overexpression.Additionally,TI demonstrated resistance reversal to PAC in xenograft models without detectable toxicities.This study establishes TI's MDR reversal effect in ABCB1-mediated MDR human cancer cells through inhibition of PRMT1-mediated aDMA of EGFR,suggesting TI's potential as an MDR modulator for improving chemotherapy outcomes.
文摘Patients admitted with prediabetes and atrial fibrillation are at high risk for major adverse cardiac or cerebrovascular events independent of confounding variables.The shared pathophysiology between these three serious but common diseases and their association with atherosclerotic cardiovascular risk factors establish a vicious circle culminating in high atherogenicity.Because of that,it is of paramount importance to perform risk stratification of patients with prediabetes to define phenotypes that benefit from various interventions.Furthermore,stress hyperglycemia assessment of hospitalized patients and consensus on the definition of prediabetes is vital.The roles lifestyle and metformin play in prediabetes are well established.However,the role of glucagon-like peptide agonists and metabolic surgery is less clear.Prediabetes is considered an intermediate between normoglycemia and diabetes along the blood glucose continuum.One billion people are expected to suffer from prediabetes by the year 2045.Therefore,realworld randomized controlled trials to assess major adverse cardiac or cerebrovascular event risk reduction and reversal/prevention of type 2 diabetes among patients are needed to determine the proper interventions.
基金supported by the National Natural Science Foundation of China[grant numbers U2442207,42122034,42075043,and 42330609]the Youth Innovation Promotion Association[grant number 2021427]+2 种基金the West Light Foundation[grant number xbzgzdsys-202409]of the Chinese Academy of Sciencesthe Key Talent Projects in Gansu Provincethe Central Guidance Fund for Local Science and Technology Development Projects in Gansu Province[grant number 24ZYQA031].
文摘Previous studies have indicated a global reversal of near-surface wind speeds from a declining trend to an increasing trend around 2010;however,it remains unclear whether upper-air wind speeds exhibit a similar reversal.This study evaluates reanalysis products using surface and radiosonde observations to analyze upper-air wind speed variations in the Northern Hemisphere,focusing on their seasonal and latitudinal differences.Results demonstrate that JRA-55 effectively captures wind speed variations in the Northern Hemisphere.Notably,upper-air wind speeds over land experienced a reversal in winter 2010 with significant latitudinal differences.The trend reversal of upper wind speed between the midlatitudes and subtropics presents a dipole pattern.From 1990 to 2010,upper-air wind speeds in the midlatitudes(40°-70°N)significantly declined,while the subtropical zone(20°-40°N)displayed an opposite trend.However,during 2010-2020,wind speeds in the midlatitudes shifted to a significant positive trend,whereas the subtropics experienced a significant negative trend.The variations in Northern Hemisphere winter wind speeds can be attributed to changes in low-level baroclinicity driven by tropical diabatic heating and midlatitude transient eddy feedback.Enhanced diabatic heating and weakened eddy feedback during 1990-2010 contributed to reduced wind speeds in the midlatitudes and increased speeds in the subtropics,while reduced diabatic heating and strengthened eddy feedback during 2010-2020 resulted in increased wind speeds in the midlatitudes and decreased speeds in the subtropics.The reversal of upper-air wind speeds could affect surface wind speeds by downward momentum transfer,which could contribute to the reversal of surface wind speeds.
基金partially supported by the following funding sources:The National Natural Science Foundation of China(No.61771084)the Chongqing Graduate Scientific Research Innovation Project(No.CYB21200)。
文摘In high-speed multiuser Time Reversal(TR)downlink systems,the transmission rate is degraded due to the presence of severe inter-user and inter-symbol interference.Moreover,maximizing the weighted sum rate in such systems is a critical objective,since the weighting factors represent the priority of different users in different applications.However,it faces significant challenges as it is an NP-hard and non-convex problem.In order to suppress these interferences and maximize the weighted sum rate,in this paper we present a novel approach for the joint design of the pre-filters.The proposed method applies successive convex approximation to transform the original problem into a Second-Order Cone Programming(SOCP)problem.Then,a low-complexity iterative algorithm is provided to effectively solve the resulting SOCP problem.According to the simulation results,the proposed method reaches a local optimum within a few iterations and demonstrates superior performance in terms of weighted sum rate compared to the current algorithm.
基金supported by National Natural Science Foundation of China(Nos.82473949 and 82273955)Scientific research project of Jiangsu Provincial Health Commission(No.M2022080)+1 种基金Jiangsu Province Capability Improvement Project through Science,Technology and Education(ZDXK202234)Jiangsu Provincial Research Hospital(YJXYY202204),China.
文摘The effective intracellular accumulation of doxorubicin(DOX)is crucial for improving antitumor efficacy,which is severely impeded by limited drug penetration,uncontrollable drug release,and drug resistance.In this study,a thermal-deformative polymer embedding ultrasmall ceria(CeO_(2))was rationally designed for deep tumor drug shuttling and hypoxia reversal to improve chemotherapy.Structurally,the CeO_(2)nanozyme was covalently grafted with a polymer of p(NIPAM-co-AM)that could sharply shrink for DOX loading,which was consolidated with polydopamine(PDA)film encapsulation.Thereafter,a tumor penetration guide of apolipoprotein A-I(apoA-I)conjugated iRGD peptide(apoA-I-iRGD)was further decorated onto the PDA shell via Michael addition for preparing CeO_(2)P/DOX@iAPDA.With the aid of apoA-I-iRGD,CeO_(2)P/DOX@iAPDA penetrated both the tumor spheroids(∼78μm)and the tumors of the mouse model deeply.After internalization by tumor cells and triggering by low pH in lysosomes,rapid DOX release was achieved by peeling off the PDA shell and thermosensitive deformation of p(NIPAM-co-AM).CeO_(2)P/DOX@iAPDA provided 66.4%tumor suppression in 4T1-derived tumor spheroids and 63.2%in 4T1-tumorbearing mice,respectively.Preliminary mechanistic research involving western blotting and immunohistochemistry revealed that CeO_(2)P/DOX@iAPDA reversed resistance through the through HIF-1α-P-gp/lipid axis.Collectively,this study intelligently integrated CeO_(2)nanozymes,temperature-sensitive polymers,and imitated biochemical modifications to improve chemotherapy for breast cancer.
基金Supported by Chongqing Municipal Health Commission Medical Research Project,No.2023WSJK104.
文摘BACKGROUND There is an increased maturation of laparoscopic intracorporeal anastomosis techniques.However,research on its application for small bowel stoma reversal in patients with Crohn's disease(CD)is limited.Therefore,in this study,we compared the perioperative outcomes between laparoscopic intracorporeal ileostomy reversal(LIIR)and open ileostomy reversal(OIR).AIM To compare the safety,feasibility,bowel function recovery,and short-and longterm LIIR and OIR outcomes in patients with CD.METHODS This study included patients who underwent ileal reversal for CD between January 2021 and January 2023 at our institution.The baseline data,postoperative recovery,and complication indicators were retrospectively analyzed.Logistic regression analysis was conducted to explore factors that significantly influenced the development of enteral nutrition intolerance-related symptoms.RESULTS Notably,15 of the 45 patients in this study underwent OIR,and the remaining 30 received LIIR.Notably,no statistically significant differences were found between the two groups regarding clinical baseline characteristics,operation time,intraoperative hemorrhage,anastomotic site,enterolysis range,first postoperative flatus,postoperative complications,reoperation rate,or incidence of postoperative enteral nutrition intolerance.Compared with the OIR group,the LIIR group had a shorter postoperative hospital stay(P=0.045),lower incidence of enteral nutrition intolerance symptoms(P=0.019),and earlier postoperative total enteral nutrition initiation(P=0.033);however,it incurred higher total hospital costs(P=0.038).Furthermore,multivariate logistic regression analysis revealed that the duration of surgery and anastomotic technique were independent risk factors for postoperative symptoms of enteral nutrition intolerance(P<0.05).CONCLUSION Laparoscopic intracorporeal anastomosis for ileostomy reversal is safe and feasible.Patients who underwent this technique demonstrated improved tolerance to postoperative enteral nutrition and quicker resumption of total enteral nutrition.
文摘In this editorial,we comment on an article by Liu et al.We focus specifically on the novel use of laparoscopic intracorporeal anastomosis(LIA)compared with open ileostomy reversal in patients with Crohn’s disease(CD),which is an innovative approach for improving postoperative outcomes and accelerating recovery in ileostomy reversal procedures.This study also highlights the limitations of the conventional open surgical technique,which is associated with higher rates of feeding intolerance,prolonged hospital stays,and delayed initiation of enteral nutrition.The chronic and recurrent nature of CD and the challenges posed by traditional surgical methods are issues addressed by LIA,which offers a minimally invasive approach that reduces surgical trauma,shortens recovery time,and improves tolerance to enteral nutrition,thereby enhancing postoperative outcomes.However,while LIA shows great promise,further prospective multicenter trials are needed to validate these findings and assess their broader application in other surgical scenarios.Overall,LIA represents a significant advancement in minimally invasive surgery for CD and has the potential to become the preferred standard approach for ileostomy reversal in patients requiring bowel reanastomosis.
基金supported by the National Natural Science Foundation of China(Grant No.12404011)the Natural Science Foundation of Hunan Province(Grant No.2023JJ40273)the Scientific Research Foundation of Hunan Provincial Education Department(Grant No.23B0495).
文摘Time-reversal symmetry(TRS)breaking induced dissipationless topological phonon edge modes provide an unprecedented way to manipulate phonon transport.However,the effect of TRS breaking on the transport properties of bulk phonon modes is still unclear.In this work,we assess the effect of local TRS-breaking domains on the transport properties of bulk phonon modes in a two-dimensional(2D)hexagonal phononic lattice model.The results show that bulk phonon modes can be strongly scattered by local TRS breaking owing to the shift of the local phonon band gap,which results in significant suppression of phonon transmission.Moreover,we show that the aperiodic distribution of local TRS-breaking domains can induce phonon Anderson localization,and the localization length can be effectively tuned by the strength of TRS breaking.Our study suggests that TRS breaking can not only be used to construct dissipationless topological phonon edge states,but also be used to block the transmission of bulk phonon modes by carefully controlling the size and distribution of TRS-breaking domains.Such results provide a highly alternative way for manipulating energy flux at the nanoscale.
基金Gansu Provincial Department of Education:Innovation Fund Project for College Teachers:Research on the Governance of Network Public Opinion Reversal Based on Blockchain Technology(NO.2025A-137)Teaching Reform Research at the School Level of Gansu University of Political Science and Law in 2024:Research and Implementation of CSCW Cloud Storage Collective Lesson Preparation System Based on Blockchain Technology(NO.GZJG2024-A04)+1 种基金2024 Gansu University of Political Science and Law“Three in One Education”Research:Project Research and Implementation of CSCW Network Teaching Platform Based on Web in the Direction of Network Education(NO.GZSQYR-37)2024 Lanzhou Philosophy and Social Sciences Planning Project:Research on Cloud Governance of Network Public Opinion for Major Public Events in Lanzhou City(NO.24-B45)。
文摘In recent years,the network public opinion reversal governance events have occurred frequently.Over time,the repeated truth of the matter will not only weaken the rational judgment of the public to a certain extent,so that its negative emotions accumulate,but also have a serious impact on the credibility of the media and the government,and may even further intensify social contradictions.Therefore,in the face of such a complex online public opinion space,accurately identifying the truth behind the incident and how to carry out the reversal of online public opinion governance is particularly critical.And blockchain technology,with its advantages of decentralization and immutable information,provides new technical support for the network public opinion reversal governance.Based on this,this paper gives an overview and analysis of blockchain technology and network public opinion reversal,and on this basis introduces the network public opinion reversal governance mechanism based on blockchain technology,aiming to further optimize the network public opinion reversal governance process,for reference only.
文摘Aim To analyze the transient speciality of nonlinear, anisotropic, AC+DC coupling electric field, and to compare the withstand voltage strength of different insulation structures. Methods The transient process of polarity reversal is analyzed, considering the anisotropic property of oil immersed press board, a new finite element model based on Galerkin method is presented and verified. The model developed is applied to calculate the electric field distribution in four typical winding end structures of the converter transformer. Results\ The whole ring structure possesses the best insulation characteristics. Conclusion\ By introducing reasonable insulation components, insulation strength with the same surrounding sizes can be improved more than 30%.
基金supported by Zhejiang Provincial Natural Science Foundation of China(No.LGC20E010004)the Science Foundation for Distinguished Young Scholars of Zhejiang Province(No.LR15E010001)+2 种基金the National Natural Science Foundation of China(No.51871205)the Key R&D Program of Zhejiang Province of China(No.2017C01004)the National Key Research and Development Project(No.2019YFF0217205)。
文摘In the present work,the magnetization reversal behavior for the melt spinning(Nd_(0.8)Ce_(0.2))_(2)Fe_(12)Co_(2-x)Zr_(x)B(x=0,0.5)permanent alloys with high coercivity was investigated by analyzing the hysteresis curves and the recoil loops.Compared to the Zr-free alloy,the Zr-doped sample obtains higher magnetic properties:coercivity of H_(cj)=650.5 kA·m^(-1),squareness of H_(k)/H_(cj)=0.76 and maximum energy product of(BH)_(max)=131.0 kJ·m^(-3).The first-order reversal curves(FORCs)analysis was taken to identify optimal conditions of exchange coupling for the Zr-free and Zr-doped alloys.The coercivity mechanism of theα-Fe/Nd_(2)Fe_(14)B nanocomposite alloys was analyzed by the angular dependence of the coercive field as measured for the Zr-doped sample.The results show that the magnetic reverse process of the Zr-doped sample can be explained by the pinning model.
基金Project supported by the National Natural Science Foundation of China (Nos. 60702022 and 60772094)the National Basic Re-search Program (973) of China (No. 5132103ZZT21B)
文摘This paper presents a detailed analysis of the effects of noise (reverberation) on the focusing performance of de-composition of the time reversal operator (DORT) in a noise-limited case and in a reverberation-limited case, respectively. Quantitative results obtained from simulations and experiments are presented. The results show the DORT method can be effi-ciently applied to target detection with enough source level to yield significant backscatter. For a target placed on the bottom, the influence of the reverberation on the focusing performance is slight. However, distinguishing between a target and constant backscattering returning from strong local clutter on the bottom (false alarms) needs further research.
基金supported by the National Natural Science Foundation of China(6130127161331007)+2 种基金the Specialized Research Fund for the Doctoral Program of Higher Education of China(2011018512000820120185130001)the Fundamental Research Funds for Central Universities(ZYGX2012J043)
文摘An efficient hybrid time reversal（TR） imaging method based on signal subspace and noise subspace is proposed for electromagnetic superresolution detecting and imaging. First, the locations of targets are estimated by the transmitting-mode decomposition of the TR operator（DORT） method employing the signal subspace. Then, the TR multiple signal classification（TR-MUSIC）method employing the noise subspace is used in the estimated target area to get the superresolution imaging of targets. Two examples with homogeneous and inhomogeneous background mediums are considered, respectively. The results show that the proposed hybrid method has advantages in CPU time and memory cost because of the combination of rough and fine imaging.
文摘In this paper, a new method of time reversal for defect diagnosis of concealed structure has been proposed based on the detecting technique of structure acoustic wave and the theory of time reversal. The time reversal recurrence formula for detecting the acoustic wave speed constitution of concealed structures with bilevel asynchronous test has been established. The wave speed constitution can be reconstructed in 2 D graticule form by means of this method. The result of model test shows the method is valid.
基金Project supported by the Natural Science Foundation of Gansu Province, China (Grant No. 22JR5RA775)the Science and Technology Program of Lanzhou, China (Grant No. 2021-1-157)+2 种基金the Guangdong Basic and Applied Basic Research Foundation, China (Grant Nos. 2020A1515110998 and 2022A1515012123)the Outstanding Youth Foundation of Gansu Academy of Science, China (Grant No. 2021YQ01)the Innovative Team Construction Project of Gansu Academy of Sciences, China (Grant No. 2020CX005-01)。
文摘Perpendicular synthetic-antiferromagnet(p-SAF) has broad applications in spin-transfer-torque magnetic random access memory and magnetic sensors. In this study, the p-SAF films consisting of (Co/Ni)3]/Ir(tIr)/[(Ni/Co)3are fabricated by magnetron sputtering technology. We study the domain structure and switching field distribution in p-SAF by changing the thickness of the infrared space layer. The strongest exchange coupling field(Hex) is observed when the thickness of Ir layer(tIr) is 0.7 nm and becoming weak according to the Ruderman–Kittel–Kasuya–Yosida-type coupling at 1.05 nm,2.1 nm, 4.55 nm, and 4.9 nm in sequence. Furthermore, the domain switching process between the upper Co/Ni stack and the bottom Co/Ni stack is different because of the antiferromagnet coupling. Compared with ferromagnet coupling films, the antiferromagnet samples possess three irreversible reversal regions in the first-order reversal curve distribution.With tIrincreasing, these irreversible reversal regions become denser and smaller. The results from this study will help us understand the details of the magnetization reversal process in the p-SAF.
基金Project supported by the National Key R&D Program of China(Grant No.2021YFC2203503)。
文摘The electromagnetic time-reversal(TR)technique has the characteristics of spatiotemporal focusing in a time-reversal cavity(TRC),which can be used for pulse compression,thus forming an electromagnetic pulse with high peak power.A time-reversed pulse-compression method in a single channel has high pulse compression gain.However,single channel pulse compression can only generate limited gain.This paper proposes a novel TR power-combination method in a multichannel TRC to obtain higher peak power based on TR pulse-compression theory.First,the TR power-combination model is given,and the crosstalk properties of the associated channel and the influence of the reversal performance are studied.Then,the power-combination performances for the TR pulse compression,such as combined signal to noise ratio(SNR)and combined compression gain,are analyzed by numerical simulation and experimental methods.The results show that the proposed method has obvious advantages over pulse-compression methods using a single channel cavity,and is more convenient for power combination.
基金supported by the National Key R&D Program of China (Grant No.2016YFA0600703)the National Natural Science Foundation of China (Grant Nos.41505073 and 41605059)+1 种基金the Research Council of Norway–supported project SNOWGLACE (Grant No.244166/E10)and the Young Talent Support Program of the China Association for Science and Technology (Grant No.2016QNRC001)
文摘During 1979–2015, the intensity of the Siberian high(SH) in November and December–January(DJ) is frequently shown to have an out-of-phase relationship, which is accompanied by opposite surface air temperature and circulation anomalies.Further analyses indicate that the autumn Arctic sea ice is important for the phase reversal of the SH. There is a significantly positive(negative) correlation between the November(DJ) SH and the September sea ice area(SIA) anomalies. It is suggested that the reduction of autumn SIA induces anomalous upward surface turbulent heat flux(SHF), which can persist into November, especially over the Barents Sea. Consequently, the enhanced eddy energy and wave activity flux are transported to mid and high latitudes. This will then benefit the development of the storm track in northeastern Europe. Conversely, when downward SHF anomalies prevail in DJ, the decreased heat flux and suppressed eddy energy hinder the growth of the storm track during DJ over the Barents Sea and Europe. Through the eddy–mean flow interaction, the strengthened(weakened)storm track activities induce decreased(increased) Ural blockings and accelerated(decelerated) westerlies, which makes the cold air from the Arctic inhibited(transported) over the Siberian area. Therefore, a weaker(stronger) SH in November(DJ) occurs downstream. Moreover, anomalously large snowfall may intensify the SH in DJ rather than in November. The ensemble-mean results from the CMIP5 historical simulations further confirm these connections. The different responses to Arctic sea ice anomalies in early and middle winter set this study apart from earlier ones.
