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 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
Filters,as a key component in the photoelectric detection system,can simplify the optical system and improve detection efficiency.Based on the usage requirements,a visible/near-infrared filter film with up to 5 waveba...Filters,as a key component in the photoelectric detection system,can simplify the optical system and improve detection efficiency.Based on the usage requirements,a visible/near-infrared filter film with up to 5 wavebands needs to be designed and prepared,while simultaneously satisfying high reflection in 2 wave-bands and high transmittance in 3 wavebands.Therefore,we have conducted a systematic study on the film design,thin film preparation process,and control accuracy of film layer thickness.In this work,the short-wave pass film system is superimposed with the long-wave pass film system,and the number of cycles and matching coefficient of the film system are tuned to meet the requirements of cut-off band.Additionally,Smith method was used to match bandpass film system to optimize the transmission band and complete the visible/near infrared multiband laser filter film design.In the preparation process,combined with the sensitiv-ity of the film layer,inverse analysis is used to invert the film layer monitored by each optical monitoring chip.The optical control scheme with weak optical signal in the monitoring process is simulated and correc-ted,and the monitoring wavelength with stronger optical signal is matched,resulting in an improvement of the control accuracy for the film thickness and the transmittance in the specified wavelength range.Ulti-mately,the actual physical thickness is 9.66μm,and the error with the theoretical design thickness is less than 0.4%,and the transmittance of the specified 3 wavebands exceeds 99%.The average transmittance of the cut-off bands at the 455−500 nm and 910−1000 nm is 0.45% and 0.16%,respectively.展开更多
New-skeleton terpenoids have prompted considerable interest owing to their chemical and biological significance.A chemical study on the bark of Croton laui led to the isolation and identification of a new norsesterter...New-skeleton terpenoids have prompted considerable interest owing to their chemical and biological significance.A chemical study on the bark of Croton laui led to the isolation and identification of a new norsesterterpenoid,crolatinoid A(1),and two new neoclerodane diterpenoids,crolatinoids B and C(2 and 3).Structurally,compound 1 exhibits an unprecedented 12,17-cyclo20-nor phenyllabdane skeleton.Compound 2 features a novel 19(5→4)-abeo-3,5-cycloneoclerodane skeleton,which is hypothetically derived from precursor 3 through an oxa-di-π-methane rearrangement process.Furthermore,compound 1 demonstrated a significant capacity to reverse multidrug resistance in paclitaxel-resistant HCT-15 cells with a reversal fold value of 16.All three compounds displayed adipogenesis inhibition in 3T3-L1 adipocytes.展开更多
Magnesium hydride(MgH_(2)) demonstrates immense potential as a solid-state hydrogen storage material,while its commercial utilization is impeded by the elevated operating temperature and sluggish reaction kinetics.Her...Magnesium hydride(MgH_(2)) demonstrates immense potential as a solid-state hydrogen storage material,while its commercial utilization is impeded by the elevated operating temperature and sluggish reaction kinetics.Herein,a MOF derived multi-phase FeNi_(3)-S catalyst was specially designed for efficient hydrogen storage in MgH_(2).Experiments confirmed that the incorporation of FeNi_(3)-S into MgH_(2) significantly lowered the desorption temperature and accelerated the kinetics of hydrogen desorption and reabsorption.The initial dehydrogenation temperature of the MgH_(2)+10 wt% FeNi_(3)-S composite was 202 ℃,which was 123 ℃ lower than that of pure MgH_(2).At 325 ℃,the MgH_(2)+10 wt% FeNi_(3)-S composite released 6.57 wt% H_(2)(fully dehydrogenated) within 1000 s.Remarkably,MgH_(2)+ 10 wt% FeNi_(3)-S composite initiated rehydrogenation at room temperature and rapidly absorbed 2.49 wt% H_(2) within 30 min at 100 ℃.Moreover,6.3 wt% H_(2) was still retained after 20 cycles at 300 ℃,demonstrating the superior cycling performance of the MgH_(2)+10 wt% FeNi_(3)-S composite.The activation energy fitting calculations further evidenced the addition of FeNi_(3)-S enhanced the de/resorption kinetics of MgH_(2)(E_(a)= 98.6 k J/mol and 43.3 k J/mol,respectively).Through phase and microstructural analysis,it was determined that the exceptional hydrogen storage performance of the composite was attributed to the in-situ formation of Mg/Mg_(2)Ni + Fe/MgS and MgH_(2)/Mg_(2)NiH_(4)+Fe/MgS hydrogen storage systems.Further mechanistic analysis revealed that Mg_(2)Ni/Mg_(2)NiH_(4) served as “hydrogen pump” and Fe/Mg S served as “hydrogen diffusion channel”,thus accelerating the dissociation and recombination of hydrogen molecules.In conclusion,this work offers insight into catalysts combining transition metal alloys and transition metal sulfide for exerting muti-phase synergistic effect on boosting the dehydrogenation/hydrogenation reactions of MgH_(2),which can also inspire future pioneering work on designing and fabricating high efficient catalysts in other energy storage related areas.展开更多
Lysine-targeting reversible covalent inhibitors,particularly salicylaldehyde-based compounds such as the Food and Drug Administration(FDA)-approved drug Voxelotor,exhibit significant therapeutic potential but are limi...Lysine-targeting reversible covalent inhibitors,particularly salicylaldehyde-based compounds such as the Food and Drug Administration(FDA)-approved drug Voxelotor,exhibit significant therapeutic potential but are limited by challenges including instability and off-target effects.To overcome these limitations in kinase inhibitor A5,we devised a pH-responsive prodrug strategy by masking its reactive aldehyde group with an acid-labile hydrazone linkage and enhancing intracellular delivery through conjugation with FK506.The optimized prodrug demonstrated robust antitumor efficacy in K562 tumor-bearing mice.Furthermore,the incorporation of the photosensitizer chlorin e6(Ce6)led to the formation of self-assembled nanoparticles(AKNP),which not only improved physiological stability and prolonged tumor retention but also enabled light-triggered release of A5 in conjunction with photodynamic therapy(PDT).Our study thus presents a promising prodrug self-assembly strategy that combines the on-demand release of a novel lysine-targeting,reversible covalent kinase inhibitor with PDT in clinical cancer therapy.展开更多
The nervous system function requires a precise but plastic neural architecture.The neuronal shape dictates how neurons interact with each other and with other cells,being the morphology of dendrites and axons the cent...The nervous system function requires a precise but plastic neural architecture.The neuronal shape dictates how neurons interact with each other and with other cells,being the morphology of dendrites and axons the central determinant of the functional properties of neurons and neural circuits.The topological and structural morphology of axons and dendrites defines and determines how synapses are conformed.The morphological diversity of axon and dendrite arborization governs the neuron’s inputs,synaptic integration,neuronal computation,signal transmission,and network circuitry,hence defining the particular connectivity and function of the different brain areas.展开更多
Current thermochromic materials for smart windows suffer from poor environmental stability,lack of self-healing and recyclability,and susceptibility to contamination.In this study,thermochromic supramolecular ionogels...Current thermochromic materials for smart windows suffer from poor environmental stability,lack of self-healing and recyclability,and susceptibility to contamination.In this study,thermochromic supramolecular ionogels with excellent environmental stability,efficient room-temperature self-healing and recyclability properties,as well as amphiphobic slippery surfaces,are fabricated by incorporating binary ionic liquids into a rationally designed self-healing polyurethane with perfluoroalkyl side chains.The outstanding and stable thermochromic performance of the resulting ionogels stems from the hydrogen bond-mediated,confined,and reversible phase separation of ionic liquids within the polyurethane network,enabling the ionogels to effectively reduce indoor temperatures and enhance the comfort of occupants.The surface-enriched perfluoroalkyl side chains enable various liquids,including water,alkanes,and edible oils,to easily slide off the ionogel surface without leaving any residue,preventing the transmittance decrease and thermochromic performance degradation caused by contaminations.The dynamic hydrogen bonds within the polyurethane network enable the ionogels to repeatedly heal physical and chemical damages,as well as to be recycled multiple times without performance loss,thereby reducing maintenance costs and minimizing material waste.This study provides a novel approach to developing advanced thermochromic materials for smart windows,potentially improving the building energy efficiency and sustainability.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%.
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.
文摘Filters,as a key component in the photoelectric detection system,can simplify the optical system and improve detection efficiency.Based on the usage requirements,a visible/near-infrared filter film with up to 5 wavebands needs to be designed and prepared,while simultaneously satisfying high reflection in 2 wave-bands and high transmittance in 3 wavebands.Therefore,we have conducted a systematic study on the film design,thin film preparation process,and control accuracy of film layer thickness.In this work,the short-wave pass film system is superimposed with the long-wave pass film system,and the number of cycles and matching coefficient of the film system are tuned to meet the requirements of cut-off band.Additionally,Smith method was used to match bandpass film system to optimize the transmission band and complete the visible/near infrared multiband laser filter film design.In the preparation process,combined with the sensitiv-ity of the film layer,inverse analysis is used to invert the film layer monitored by each optical monitoring chip.The optical control scheme with weak optical signal in the monitoring process is simulated and correc-ted,and the monitoring wavelength with stronger optical signal is matched,resulting in an improvement of the control accuracy for the film thickness and the transmittance in the specified wavelength range.Ulti-mately,the actual physical thickness is 9.66μm,and the error with the theoretical design thickness is less than 0.4%,and the transmittance of the specified 3 wavebands exceeds 99%.The average transmittance of the cut-off bands at the 455−500 nm and 910−1000 nm is 0.45% and 0.16%,respectively.
基金support from the National Key Research and Development Program of China(No.2023YFE0206100)the National Natural Science Foundation of China(Nos.22237007 and T2192972)+1 种基金the Youth Innovation Promotion Association of Chinese Academy of Sciences(CAS)(No.2022282)Shanghai Institute of Materia Medica of CAS(No.SIMM0120231002)is gratefully acknowledged.
文摘New-skeleton terpenoids have prompted considerable interest owing to their chemical and biological significance.A chemical study on the bark of Croton laui led to the isolation and identification of a new norsesterterpenoid,crolatinoid A(1),and two new neoclerodane diterpenoids,crolatinoids B and C(2 and 3).Structurally,compound 1 exhibits an unprecedented 12,17-cyclo20-nor phenyllabdane skeleton.Compound 2 features a novel 19(5→4)-abeo-3,5-cycloneoclerodane skeleton,which is hypothetically derived from precursor 3 through an oxa-di-π-methane rearrangement process.Furthermore,compound 1 demonstrated a significant capacity to reverse multidrug resistance in paclitaxel-resistant HCT-15 cells with a reversal fold value of 16.All three compounds displayed adipogenesis inhibition in 3T3-L1 adipocytes.
基金supported by the National Key R&D Program of China (No.2022YFB3803703)the National Natural Science Foundation of China (Nos.52071141,52271212,52201250,51771056,22305104)+1 种基金the Natural Science Foundation of Jiangsu Province (No.BK20210893)the Ministry of Science and Technology of the People’s Republic of China (No.G2023014022L)。
文摘Magnesium hydride(MgH_(2)) demonstrates immense potential as a solid-state hydrogen storage material,while its commercial utilization is impeded by the elevated operating temperature and sluggish reaction kinetics.Herein,a MOF derived multi-phase FeNi_(3)-S catalyst was specially designed for efficient hydrogen storage in MgH_(2).Experiments confirmed that the incorporation of FeNi_(3)-S into MgH_(2) significantly lowered the desorption temperature and accelerated the kinetics of hydrogen desorption and reabsorption.The initial dehydrogenation temperature of the MgH_(2)+10 wt% FeNi_(3)-S composite was 202 ℃,which was 123 ℃ lower than that of pure MgH_(2).At 325 ℃,the MgH_(2)+10 wt% FeNi_(3)-S composite released 6.57 wt% H_(2)(fully dehydrogenated) within 1000 s.Remarkably,MgH_(2)+ 10 wt% FeNi_(3)-S composite initiated rehydrogenation at room temperature and rapidly absorbed 2.49 wt% H_(2) within 30 min at 100 ℃.Moreover,6.3 wt% H_(2) was still retained after 20 cycles at 300 ℃,demonstrating the superior cycling performance of the MgH_(2)+10 wt% FeNi_(3)-S composite.The activation energy fitting calculations further evidenced the addition of FeNi_(3)-S enhanced the de/resorption kinetics of MgH_(2)(E_(a)= 98.6 k J/mol and 43.3 k J/mol,respectively).Through phase and microstructural analysis,it was determined that the exceptional hydrogen storage performance of the composite was attributed to the in-situ formation of Mg/Mg_(2)Ni + Fe/MgS and MgH_(2)/Mg_(2)NiH_(4)+Fe/MgS hydrogen storage systems.Further mechanistic analysis revealed that Mg_(2)Ni/Mg_(2)NiH_(4) served as “hydrogen pump” and Fe/Mg S served as “hydrogen diffusion channel”,thus accelerating the dissociation and recombination of hydrogen molecules.In conclusion,this work offers insight into catalysts combining transition metal alloys and transition metal sulfide for exerting muti-phase synergistic effect on boosting the dehydrogenation/hydrogenation reactions of MgH_(2),which can also inspire future pioneering work on designing and fabricating high efficient catalysts in other energy storage related areas.
基金supported by the grants from National Key R&D Program of China(No.2022YFA1104800)Shenzhen Science and Technology Program(No.JCYJ20210324124214038)+4 种基金National Natural Science Foundation of China(Nos.52072418,82300016)Natural Science Foundation of Guangdong Province(No.2023A1515140072)Shenzhen Key Laboratory of Neural Cell Reprogramming and Drug Research,Social Development Science and Technology Key Project of Dongguan(No.20231800940512)the National Medical Research Council(NMRC,No.23-0740-A0001)the Ministry of Education(MOE,No.T2EP10222-0002)of Singapore.
文摘Lysine-targeting reversible covalent inhibitors,particularly salicylaldehyde-based compounds such as the Food and Drug Administration(FDA)-approved drug Voxelotor,exhibit significant therapeutic potential but are limited by challenges including instability and off-target effects.To overcome these limitations in kinase inhibitor A5,we devised a pH-responsive prodrug strategy by masking its reactive aldehyde group with an acid-labile hydrazone linkage and enhancing intracellular delivery through conjugation with FK506.The optimized prodrug demonstrated robust antitumor efficacy in K562 tumor-bearing mice.Furthermore,the incorporation of the photosensitizer chlorin e6(Ce6)led to the formation of self-assembled nanoparticles(AKNP),which not only improved physiological stability and prolonged tumor retention but also enabled light-triggered release of A5 in conjunction with photodynamic therapy(PDT).Our study thus presents a promising prodrug self-assembly strategy that combines the on-demand release of a novel lysine-targeting,reversible covalent kinase inhibitor with PDT in clinical cancer therapy.
基金supported by the Wellcome Trust(grant No.103852).
文摘The nervous system function requires a precise but plastic neural architecture.The neuronal shape dictates how neurons interact with each other and with other cells,being the morphology of dendrites and axons the central determinant of the functional properties of neurons and neural circuits.The topological and structural morphology of axons and dendrites defines and determines how synapses are conformed.The morphological diversity of axon and dendrite arborization governs the neuron’s inputs,synaptic integration,neuronal computation,signal transmission,and network circuitry,hence defining the particular connectivity and function of the different brain areas.
基金supported by the National Natural Science Foundation of China(22475082,21971083)。
文摘Current thermochromic materials for smart windows suffer from poor environmental stability,lack of self-healing and recyclability,and susceptibility to contamination.In this study,thermochromic supramolecular ionogels with excellent environmental stability,efficient room-temperature self-healing and recyclability properties,as well as amphiphobic slippery surfaces,are fabricated by incorporating binary ionic liquids into a rationally designed self-healing polyurethane with perfluoroalkyl side chains.The outstanding and stable thermochromic performance of the resulting ionogels stems from the hydrogen bond-mediated,confined,and reversible phase separation of ionic liquids within the polyurethane network,enabling the ionogels to effectively reduce indoor temperatures and enhance the comfort of occupants.The surface-enriched perfluoroalkyl side chains enable various liquids,including water,alkanes,and edible oils,to easily slide off the ionogel surface without leaving any residue,preventing the transmittance decrease and thermochromic performance degradation caused by contaminations.The dynamic hydrogen bonds within the polyurethane network enable the ionogels to repeatedly heal physical and chemical damages,as well as to be recycled multiple times without performance loss,thereby reducing maintenance costs and minimizing material waste.This study provides a novel approach to developing advanced thermochromic materials for smart windows,potentially improving the building energy efficiency and sustainability.
