BACKGROUND Post-transplant tertiary hyperparathyroidism(PT-tHPT)is a well-recognized complication following kidney transplantation,characterized by persistent excessive secretion of parathyroid hormone(PTH)despite imp...BACKGROUND Post-transplant tertiary hyperparathyroidism(PT-tHPT)is a well-recognized complication following kidney transplantation,characterized by persistent excessive secretion of parathyroid hormone(PTH)despite improved renal function.It is potentially associated with an increased risk of cardiovascular events,renal osteodystrophy,pathologic fractures,graft loss,and mortality.AIM To evaluate the incidence,risk factors,and outcomes of PT-tHPT amongst kidney transplant recipients.METHODS A total of 887 transplant recipients who underwent transplantation between 2000 and 2020 were evaluated.Univariable and multivariable logistic regression was performed to determine the predictors of tertiary hyperparathyroidism.Graft and recipient outcomes were assessed using multivariable Cox regression.A separate multivariable Cox regression was performed to determine the effect of treatment strategies on outcomes.RESULTS PT-tHPT,defined as elevated PTH(>65 ng/L)and persistent hypercalcemia(>2.60 mmol/L),was diagnosed in 14%of recipients.Risk factors for PT-tHPT included older age[odds ratio(OR)=1.36,P<0.001],Asian ethnicity(OR=0.33,P=0.006),total ischemia time(OR=1.03,P=0.048 per hour),pre-transplant serum calcium(OR=1.38,P<0.001)per decile increase,pre-transplant PTH level(OR=1.31,P<0.001)per decile increase,longer dialysis duration(OR=1.12,P=0.002)per year,history of acute rejection(OR=2.37,P=0.012),and slope of estimated glomerular filtration rate change(OR=0.91,P=0.001).There were a 3.4-fold higher risk of death-censored graft loss and a 1.9-fold greater risk of recipient death with PT-tHPT.The three treatment strategies of conservative management,calcimimetic and parathyroidectomy did not significantly change the graft or patient outcome.CONCLUSION Pretransplant elevated calcium and PTH levels,older age and dialysis duration are associated with PT-tHPT.While PT-tHPT significantly affects graft and recipient survival,the treatment strategies did not affect survival.展开更多
BACKGROUND The use of induction immunosuppression agents has improved kidney transplant outcomes,but selecting the optimal agent remains a point of debate.AIM To compare the long-term outcomes of kidney transplant rec...BACKGROUND The use of induction immunosuppression agents has improved kidney transplant outcomes,but selecting the optimal agent remains a point of debate.AIM To compare the long-term outcomes of kidney transplant recipients receiving alemtuzumab vs basiliximab induction,focusing on graft function,acute rejection,infection,malignancy,post-transplant glomerulonephritis,and survival,using a propensity score matched cohort design.METHODS Kidney transplant recipients who received alemtuzumab or basiliximab induction from 2014 to 2019 across two nephrology centres in Northwest England were evaluated.Propensity score matching at a 1:1.5 ratio ensured comparability between cohorts.Baseline characteristics,immunosuppression regimens,and outcomes were analyzed.Linear,binary logistic and Cox proportional hazard regression models.RESULTS A total of 436 recipients were included,with a median follow-up of 5.2 years.The matched cohort(n=262)had a mean age of 51.1±13.5 years;39%were female and 92%were white.There was no significant difference in the cumulative incidence of acute rejection[odds ratio(OR)=2.10;95%CI:0.9-4.9;P=0.110].Compared with basiliximab,alemtuzumab was associated with lower estimated glomerular filtration rate at 12 months(-6.6 mL/minute/1.73 m2;95%CI:-10.5 to-2.7;P<0.001)and higher risks of cytomegalovirus viremia(OR=3.2;95%CI:1.6-6.5;P<0.001),BK viremia(OR=2.4;95%CI:1.1-5.5;P=0.02),post-transplant malignancy(OR=6.2;95%CI:1.6-29.9;P=0.013),and death-censored graft loss(hazard ratio=3.6;95%CI:1.2-11.4;P=0.03).No significant differences were observed in post-transplant glomerulonephritis or recipient mortality.CONCLUSION In this propensity score-matched analysis,alemtuzumab induction was associated with lower graft function at 12 months and higher risks of viral infection,post-transplant malignancy,and graft loss compared with basiliximab.These findings highlight the need for further studies to confirm the long-term safety and effectiveness of alemtuzumab in kidney transplantation.展开更多
Diabetes mellitus represents a major global health issue,driving the need for noninvasive alternatives to traditional blood glucose monitoring methods.Recent advancements in wearable technology have introduced skin-in...Diabetes mellitus represents a major global health issue,driving the need for noninvasive alternatives to traditional blood glucose monitoring methods.Recent advancements in wearable technology have introduced skin-interfaced biosensors capable of analyzing sweat and skin biomarkers,providing innovative solutions for diabetes diagnosis and monitoring.This review comprehensively discusses the current developments in noninvasive wearable biosensors,emphasizing simultaneous detection of biochemical biomarkers(such as glucose,cortisol,lactate,branched-chain amino acids,and cytokines)and physiological signals(including heart rate,blood pressure,and sweat rate)for accurate,personalized diabetes management.We explore innovations in multimodal sensor design,materials science,biorecognition elements,and integration techniques,highlighting the importance of advanced data analytics,artificial intelligence-driven predictive algorithms,and closed-loop therapeutic systems.Additionally,the review addresses ongoing challenges in biomarker validation,sensor stability,user compliance,data privacy,and regulatory considerations.A holistic,multimodal approach enabled by these next-generation wearable biosensors holds significant potential for improving patient outcomes and facilitating proactive healthcare interventions in diabetes management.展开更多
Monogenic diabetes is a heterogeneous disorder characterized by hyperglycemia arising from defects in a single gene.Maturity-onset diabetes of the young(MODY)is the most common type with 14 subtypes,each linked to spe...Monogenic diabetes is a heterogeneous disorder characterized by hyperglycemia arising from defects in a single gene.Maturity-onset diabetes of the young(MODY)is the most common type with 14 subtypes,each linked to specific mutations affecting insulin synthesis,secretion and glucose regulation.Common traits across MODY subtypes include early-onset diabetes,a family history of autosomal dominant diabetes,lack of features of insulin resistance,and absent islet cell autoimmunity.Many cases are misdiagnosed as type 1 and type 2 diabetes mellitus.Biomarkers and scoring systems can help identify candidates for genetic testing.GCK-MODY,a common subtype,manifests as mild hyperglycemia and doesn’t require treatment except during pregnancy.In contrast,mutations in HNF4A,HNF1A,and HNF1B genes lead to progressive beta-cell failure and similar risks of complications as type 2 diabetes mellitus.Neonatal diabetes mellitus(NDM)is a rare form of monogenic diabetes that usually presents within the first six months.Half of the cases are lifelong,while others experience transient remission.Permanent NDM is most commonly due to activating mutations in genes encoding the adenosine triphosphate-sensitive potassium channel(KCNJ11 or ABCC8)and can be transitioned to sulfonylurea after confirmation of diagnosis.Thus,in many cases,monogenic diabetes offers an opportunity to provide precision treatment.The scope has broadened with next-generation sequencing(NGS)technologies,replacing older methods like Sanger sequencing.NGS can be for targeted gene panels,whole-exome sequencing(WES),or whole-genome sequencing.Targeted gene panels offer specific information efficiently,while WES provides comprehensive data but comes with bioinformatic challenges.The surge in testing has also led to an increase in variants of unknown significance(VUS).Deciding whether VUS is disease-causing or benign can be challenging.Computational models,functional studies,and clinical knowledge help to determine pathogenicity.Advances in genetic testing technologies offer hope for improved diagnosis and personalized treatment but also raise concerns about interpretation and ethics.展开更多
BACKGROUND Metabolic dysfunction-associated fatty liver disease(MAFLD)and type 2 diabetes mellitus(T2DM)are independent risk factors for the development of cardiovascular disease(CVD)and an exaggerated CVD risk is exp...BACKGROUND Metabolic dysfunction-associated fatty liver disease(MAFLD)and type 2 diabetes mellitus(T2DM)are independent risk factors for the development of cardiovascular disease(CVD)and an exaggerated CVD risk is expected when both diseases co-exist.Therefore,thorough risk stratification is important to inform better clinical practice decisions based on good quality evidence for patient with MAFLD and T2DM.AIM To identify the CVD and cardiovascular event(CVE)risk in a systematic review when MAFLD and T2DM co-exist to inform better clinical practice decisions.METHODS A systematic review was performed by compiling data by searching PubMed,EMBASE and Cochrane Library databases.Quality appraisal of retrieved studies and the meta-analysis were performed using Joanna Briggs Institute(JBI)tool and RevMan 5.4 software respectively.The effect indicators for CVE and CVD risk were expressed as odds ratios(OR)and 95%CI with P-values<0.05 as significant.RESULTS Fourteen(5 cohort and 9 cross-sectional)studies with 370013 participants were included in this review.The metaanalysis of CVE showed that the risk of CVE in T2DM was higher in the MAFLD group when compared to the non-MAFLD group[OR 1.28(95%CI,1.04-1.56)P=0.02]with follow up duration ranging between 5-6 years.The prevalence of CVD in the metanalysis of cross-sectional studies was found to be higher[OR 1.47(95%CI,1.21-1.78)P=0.0001]in T2DM with MAFLD when compared to T2DM without MAFLD.Significant heterogeneity exists due to variations in study design,methodologies,and MAFLD diagnostic criteria,which may have influenced the study's findings.CONCLUSION The presence of MAFLD in T2DM increased the risk of CVE.The prevalence of CVD is higher in T2DM with MAFLD as compared to T2DM without MAFLD.Large well-designed multicentric long-term prospective studies are necessary to appropriately risk stratify the cardiovascular effect of the MAFLD in T2DM patients.展开更多
BACKGROUND The incidence of type 2 diabetes mellitus(T2DM)in children and adolescents is increasing,yet there is limited information on the available pharmacological interventions to combat T2DM and prevent associated...BACKGROUND The incidence of type 2 diabetes mellitus(T2DM)in children and adolescents is increasing,yet there is limited information on the available pharmacological interventions to combat T2DM and prevent associated comorbidities.AIM To assess the effectiveness of current pharmacological treatments in managing T2DM in children and adolescents.The protocol of the study was registered in PROSPERO(CRD42022382165).METHODS Searches were performed in PubMed,EMBASE,Scopus,and ClinicalTrials.gov for publications between 1990 to September 2024 without language restrictions.Randomized control trials(RCTs)of pharmacotherapy in children and adolescents with T2DM(aged<19 years)were included.The primary outcome was a change in glycated hemoglobin(HbA1c)from baseline to follow-up.Secondary outcomes were changes in body weight,body mass index(BMI),total cholesterol,triglycerides,high density lipoprotein,and low-density lipoprotein from baseline,and incidence of adverse events during study periods.Screening,full-text review,data extraction,and assessments of risk of bias were done by two reviewers.Conflicts on each step were resolved by a third reviewer.Data analysis was performed using Review Manager Version 6.5(RevMan 6.5)and‘R’software via RStudio,‘meta’and‘netmeta’.RESULTS A total of 12 studies having low to moderate risk of bias with 1658 participants,and follow-up duration 12-52 weeks were included.In our network meta-analysis,compared to control(s),the reduction of HbA1c was sig-nificantly larger for dulaglutide[mean difference(MD),95%confidence interval:-1.20,-2.12 to-0.28],followed by dapagliflozin(-0.94,-1.44 to-0.44),liraglutide(-0.91,-1.37 to-0.45),empagliflozin(-0.87,-1.40 to-0.34),exenatide(-0.59,-1.07 to-0.11)and linagliptin(-0.45,-0.87 to-0.02)while other drugs had little or no effect.While liraglutide was associated with a change in body weight[MD-2.41(-4.68,-0.14)kg],no other drug treatment was associated with significant changes in body weight,BMI,and lipids.Apart from level 1 hypoglycemia with liraglutide[risk difference(RD):0.20,0.04-0.37]and minor adverse events with dulaglutide(RD:0.24,0.08-0.40),no other treatment was associated with excess risk of hypoglycemia or minor or major adverse events.CONCLUSION Pharmacotherapy of T2DM with dulaglutide,dapagliflozin,liraglutide,empagliflozin,exenatide,and linagliptin in children is associated with modest reduction of HbA1c.Larger RCTs with longer follow-up durations are needed to guide better therapeutic decision making.展开更多
Use of immunomodulating agents to prevent the progression of autoimmuneβ-cell damage leading to type 1 diabetes mellitus(T1DM)is an interesting area for research.These include non-specific anti-inflammatory agents,im...Use of immunomodulating agents to prevent the progression of autoimmuneβ-cell damage leading to type 1 diabetes mellitus(T1DM)is an interesting area for research.These include non-specific anti-inflammatory agents,immunologic vaccination and anti-inflammatory agents targeting specific immune cells or cytokines.Teplizumab is an anti-CD3-molecule that binds to and leads to the disappearance of the CD3/TCR complex and rendering the T cell anergic to its target antigen.Preclinical and clinical trials have demonstrated its efficacy in reducing the decline in serum C-peptide levels and the need for insulin therapy if used early in the disease process of T1DM.The benefits have been apparent as early as six months to as long as seven years after therapy.It has recently been approved by the Food and Drug Administration to delay the onset of clinical(stage 3)type 1 diabetes in children above 8 years of age.In their recent metaanalysis published in the World Journal of Diabetes,Ma et al found that those in the teplizumab treatment group have a greater likelihood of reduction in insulin use,change in C-peptide response,and better glycemic control compared to the control group with a good safety profile.However,all the included randomized control trials have been conducted in high-income countries.High cost of therapy and unknown utility of the molecule in stage 3 disease limit its widespread use.展开更多
Bacterial infection is a major threat to global public health,and can cause serious diseases such as bacterial skin infection and foodborne diseases.It is essential to develop a new method to rapidly diagnose clinical...Bacterial infection is a major threat to global public health,and can cause serious diseases such as bacterial skin infection and foodborne diseases.It is essential to develop a new method to rapidly diagnose clinical multiple bacterial infections and monitor food microbial contamination in production sites in real-time.In this work,we developed a 4-mercaptophenylboronic acid gold nanoparticles(4-MPBA-AuNPs)-functionalized hydrogel microneedle(MPBA-H-MN)for bacteria detection in skin interstitial fluid.MPBA-H-MN could conveniently capture and enrich a variety of bacteria within 5 min.Surface enhanced Raman spectroscopy(SERS)detection was then performed and combined with machine learning technology to distinguish and identify a variety of bacteria.Overall,the capture efficiency of this method exceeded 50%.In the concentration range of 1×10_(7) to 1×10^(10) colony-forming units/mL(CFU/mL),the corresponding SERS intensity showed a certain linear relationship with the bacterial concentration.Using random forest(RF)-based machine learning,bacteria were effectively distinguished with an accuracy of 97.87%.In addition,the harmless disposal of used MNs by photothermal ablation was convenient,environmentally friendly,and inexpensive.This technique provided a potential method for rapid and real-time diagnosis of multiple clinical bacterial infections and for monitoring microbial contamination of food in production sites.展开更多
Electrolyte selection for Plasma Electrolytic Oxidation(PEO)of magnesium is important as this determines composition,morphology and properties of resultant coatings that are urgently sought after for protection of Mg ...Electrolyte selection for Plasma Electrolytic Oxidation(PEO)of magnesium is important as this determines composition,morphology and properties of resultant coatings that are urgently sought after for protection of Mg alloys from corrosion and wear in harsh environments.However,electrolyte design is often performed heuristically,which hampers the development and optimisation of new PEO processes.Here,we attempt to achieve a mechanistic understanding of electrochemical and microstructural aspects of anodic films evolution at the prebreakdown stages of PEO treatments of magnesium in aqueous alkaline solutions of NaAlO_(2),Na_(3)PO_(4),Na F and Na_(2)SiO_(3).Systematic studies have shown that magnesium self-passivation by MgO/Mg(OH)_(2)can be compromised by both chemical and mechanical instabilities developed due to side effects of anodic reactions.Stable initiation of PEO process requires maintaining surface passivity in a wide range of p H,which can be achieved only by combining self-depositing passivators with those binding dissolved magnesium into insoluble compounds.展开更多
Machine Hammer Peening(MHP)is an emergent treatment that induces high compressive Residual Stresses(RS)which can enhance the in-service performance of components.This paper studies the use of small diameter MHP tools ...Machine Hammer Peening(MHP)is an emergent treatment that induces high compressive Residual Stresses(RS)which can enhance the in-service performance of components.This paper studies the use of small diameter MHP tools to improve the Surface Integrity(SI)of the nickel-based alloy Inconel 718 used in critical aero-engine components.Complementarily,the relaxation of RS is analyzed by in-situ annealing tests at in-service temperature combined with X-ray diffraction measurement.For this purpose,age hardened Inconel 718 discs were turned as reference condition,and then a pneumatic MHP tool was used under different conditions:two tool diameters(4 mm and 12 mm),feed rates(2.5 m/min and 5.0 m/min)and stepover distances(0.07 mm and 0.35 mm).Subsequently,surface topography characterization,RS measurements,nanoindentation tests,and microstructural observations were conducted.The in-situ annealing tests were done in the X-ray diffractometer at 550°C for exposure periods from 0 to 20 h.The results demonstrate that 4 mm diameter tools generate smooth surfaces and induce significant compressive RS within a0.5 mm thick layer.Residual stresses are relaxed,but they remain compressive even after a long thermal exposure.The microstructure of the surface layer(<10–15μm)was affected by the preceding turning operation,but importantly,MHP did not induce additional damage.展开更多
With the generation of both localised thermal and vibration in incremental sheet forming(ISF)by novel tool designs,rotational vibration assisted ISF(RV-ISF)can achieve significant force reduction and material softenin...With the generation of both localised thermal and vibration in incremental sheet forming(ISF)by novel tool designs,rotational vibration assisted ISF(RV-ISF)can achieve significant force reduction and material softening.However,the combined thermal and vibration softening in RV-ISF is unclear.By evaluating the similarities and differences of friction stir ISF(FS-ISF)and RV-ISF,this study develops a novel approach to decouple and quantify the thermal and vibration softening effects in RV-ISF of AZ31B-H24,providing new insights into underlying thermal and vibration softening mechanism.Experimental results reveal that in RV-ISF of AZ31B-H24 the thermal softening due to frictional heating dominates with 45∼65%of softening,while the vibration effect only contributes up to 15%of softening,from the conventional ISF,depending on the tool designs and tool rotational speed.The double-offset tool(T2)produces greater vibration softening than the three-groove tool(T3)owing to the higher vibration amplitude of the T2 tool.An increase in tool rotational speed primarily enhances thermal softening with only marginal changes to the vibration effect.Microstructural analysis suggests that with average grain size of 0.94μm at the top layer,RV-ISF with T3 and 3000 rpm is more effective for microstructure refinement than that by FS-ISF,especially on the tool-sheet contact surface,which confirms the occurrence of surface shearing.This refinement is a result of the reduced recrystallisation degree,71.8%at the top bottom layer.Compared with FS-ISF,RV-ISF can lead to not only higher geometrically necessary dislocation density,but also higher fraction of low-angle grain boundaries,indicating that softening mechanism due to localised vibration effect is resulted from the enhanced rearrangement and annihilation of dislocations.These findings contribute to new understanding of the thermal and vibration softening effects in RV-ISF of AZ31B-H24 and offer a theoretical foundation for the tool design and process optimisation.展开更多
Liquefied natural gas storage and transportation as well as space propulsion systems have sparked inter-est in the martensitic transformation and behaviours of 316 L stainless steels(SS)under ultra-cryogenic deformati...Liquefied natural gas storage and transportation as well as space propulsion systems have sparked inter-est in the martensitic transformation and behaviours of 316 L stainless steels(SS)under ultra-cryogenic deformation.In this study,high-resolution transmission electron microscopy(HRTEM)and molecular dy-namics(MD)simulations were used to investigate the atomic arrangements and crystalline defects of deformation-induced γ-austenite→ε-martensite→α'-martensite and γ→α'martensitic transforma-tions in 316 L SS at 15 and 173 K.Theγ→εtransformation involves the glide of Shockley partial dislocations on(111)γplanes without a change in atomic spacing.The formation of anα'inclusion in a singleε-band is achieved by a continuous lattice distortion,accompanied by the formation of a tran-sition zone ofα'and the expansion of the average atomic spacings due to dislocation shuffling.Asα'grows further intoγ,the orientation relationship(OR)of theα'changes by lattice bending.This pro-cess follows the Bogers-Burgers-Olson-Cohen model despite it not occurring on intersecting shear bands.Stacking faults and twins can also serve as nucleation sites forα'at 173 K.We also found that direct transformation of γ→α'occurs by the glide of √6aγ[11(2)]/12 dislocations on every(111)γplane with misfit dislocations.Overall,this study provides,for the first time,insights into the atomic-scale mech-anisms of various two-step and one-step martensitic transformations induced by cryogenic deformation and corresponding local strain,enhancing our understanding of the role of martensitic transformation under ultra-cryogenic-temperature deformation in controlling the properties.展开更多
In laser wakefield acceleration,injecting an external electron beam at a certain energy is a promising approach for achieving a high-quality electron beam with low energy spread and low emittance.In this paper,the pro...In laser wakefield acceleration,injecting an external electron beam at a certain energy is a promising approach for achieving a high-quality electron beam with low energy spread and low emittance.In this paper,the process of laser wakefield acceleration with an external injection at 10 pC has been studied in simulations.A Bayesian optimization method is used to optimize the key laser and plasma parameters so that the electron beam is accelerated to the expected energy with a small emittance and energy spread growth.The effect of the rising edge of the plasma on the transverse properties of the electron beam is simulated and optimized in order to ensure that the external electron beam is injected into the plasma without significant emittance growth.Finally,a high-quality electron beam with an energy of 1.5 GeV,a normalized transverse emittance of 0.5 mm·mrad and a relative energy spread of 0.5%at 10 pC is obtained.展开更多
Accurate prediction of pure component physiochemical properties is crucial for process integration, multiscale modelling, and optimization. In this work, an enhanced framework for pure component property prediction by...Accurate prediction of pure component physiochemical properties is crucial for process integration, multiscale modelling, and optimization. In this work, an enhanced framework for pure component property prediction by using explainable machine learning methods is proposed. In this framework, the molecular representation method based on the connectivity matrix effectively considers atomic bonding relationships to automatically generate features. The supervised machine learning model random forest is applied for feature ranking and pooling. The adjusted R^(2) is introduced to penalize the inclusion of additional features, providing an assessment of the true contribution of features. The prediction results for normal boiling point (T_(b)), liquid molar volume (L_(mv)), critical temperature (T_(c)) and critical pressure (P_(c)) obtained using Artificial Neural Network and Gaussian Process Regression models confirm the accuracy of the molecular representation method. Comparison with GC based models shows that the root-mean-square error on the test set can be reduced by up to 83.8%. To enhance the interpretability of the model, a feature analysis method based on Shapley values is employed to determine the contribution of each feature to the property predictions. The results indicate that using the feature pooling method reduces the number of features from 13316 to 100 without compromising model accuracy. The feature analysis results for Tb, Lmv, Tc, and Pc confirms that different molecular properties are influenced by different structural features, aligning with mechanistic interpretations. In conclusion, the proposed framework is demonstrated to be feasible and provides a solid foundation for mixture component reconstruction and process integration modelling.展开更多
Tropospheric ozone pollution has been worsened over most regions of China,adversely affecting human health and ecosystems.The long-term ozone concentration depends largely upon atmospheric circulations.Here,we conduct...Tropospheric ozone pollution has been worsened over most regions of China,adversely affecting human health and ecosystems.The long-term ozone concentration depends largely upon atmospheric circulations.Here,we conducted meteorological adjustment to quantitatively assess the influences of meteorological factors on the ozone evolution in China's seven city clusters during thewarm season(April to October)from 2013 to 2020.Our analysis indicated that northern and eastern regions experienced ozone increases driven by emission changes.Southern regions,particularly the Pearl River Delta(PRD),exhibited ozone rise primarily due to meteorological conditions despite emission changes.In the Sichuan Basin(SCB)and Central Yangtze River Plain(CYP),where ozone levels decreased,meteorological conditions played a significant role in suppressing the ascent of ozone.Empirical orthogonal functions(EOF)analyses suggested that the spatiotemporal trend ofmeteorologyassociated ozone was strongly correlated with the variation of East Asian Trough(EAT),South Asian High(SAH)and the western Pacific subtropical high(WPSH).The top three EOF patterns explained 33.4%,21.8%,and 16.0%of the total variance inmeteorology-associated ozone.Absolute principal component scores-multiple linear regression(APCS-MLR)analyse quantitatively identified that enhanced EAT and SAH with a northward location of WPSH were favourable to surface ozone formation in central and eastern regions,but unfavourable to ozone formation in edge regions such as SCB.展开更多
The advent of 6G wireless networks promises unprecedented connectivity,supporting ultra-high data rates,low latency,and massive device connectivity.However,these ambitious goals introduce significant challenges,partic...The advent of 6G wireless networks promises unprecedented connectivity,supporting ultra-high data rates,low latency,and massive device connectivity.However,these ambitious goals introduce significant challenges,particularly in channel estimation due to complex and dynamic propagation environments.This paper explores the concept of channel knowledge maps(CKMs)as a solution to these challenges.CKMs enable environment-aware communications by providing location-specific channel information,reducing reliance on real-time pilot measurements.We categorize CKM construction techniques into measurement-based,model-based,and hybrid methods,and examine their key applications in integrated sensing and communication(ISAC)systems,beamforming,trajectory optimization of unmanned aerial vehicles(UAVs),base station(BS)placement,and resource allocation.Furthermore,we discuss open challenges and propose future research directions to enhance the robustness,accuracy,and scalability of CKM-based systems in the evolving 6G landscape.展开更多
Conductive hydrogels have garnered widespread attention as a versatile class of flexible electronics.Despite considerable advancements,current methodologies struggle to reconcile the fundamental trade-off between high...Conductive hydrogels have garnered widespread attention as a versatile class of flexible electronics.Despite considerable advancements,current methodologies struggle to reconcile the fundamental trade-off between high conductivity and effective absorption-dominated electromagnetic interference(EMI)shielding,as dictated by classical impedance matching theory.This study addresses these limitations by introducing a novel synthesis of aramid nanofiber/MXene-reinforced polyelectrolyte hydrogels.Leveraging the unique properties of polyelectrolytes,this innovative approach enhances ionic conductivity and exploits the hydration effect of hydrophilic polar groups to induce the formation of intermediate water.This critical innovation facilitates polarization relaxation and rearrangement in response to electromagnetic fields,thereby significantly enhancing the EMI shielding effectiveness of hydrogels.The electromagnetic wave attenuation capacity of these hydrogels was thoroughly evaluated across both X-band and terahertz band frequencies,with further investigation into the impact of varying water content states-hydrated,dried,and frozen-on their electromagnetic properties.Moreover,the hydrogels exhibited promising capabilities beyond mere EMI shielding;they also served effectively as strain sensors for monitoring human motions,indicating their potential applicability in wearable electronics.This work provides a new approach to designing multifunctional hydrogels,advancing the integration of flexible,multifunctional materials in modern electronics,with potential applications in both EMI shielding and wearable technology.展开更多
BACKGROUND Endoscopic submucosal dissection(ESD)is increasingly used to treat gastric dysplasia and early neoplasia in the West.Unlike Eastern countries,data for Caucasian patients in the United Kingdom is limited due...BACKGROUND Endoscopic submucosal dissection(ESD)is increasingly used to treat gastric dysplasia and early neoplasia in the West.Unlike Eastern countries,data for Caucasian patients in the United Kingdom is limited due to its limited implementation in a few tertiary centres.AIM To evaluate the outcomes of ESD on gastric dysplasia and neoplasia in Caucasian patients.METHODS Our ten-year retrospective study at a single tertiary centre included data spanning from May 2012 to July 2023.The efficacy of ESD on gastric dysplasia and early neoplasia was measured using parameters set out by the National Institute for Health and Care Excellence,which include en-bloc and curative resection(CR)rates,local recurrence and survival rates.RESULTS ESD was attempted on 111 lesions in 93 patients.95.0%of completed procedures achieved endoscopic clearance.74.3%were en-bloc resections and the rest were hybrid ESD with piecemeal resections.In all,34.7%achieved histological CR.Overall,disease recurrence was 10.9%at latest follow-up(63 months,median follow-up).Importantly 100%of lesions in the CR group showed no disease recurrence at subsequent and latest follow-up.In the Indeterminate and Non-CR group,18.8%of lesions showed disease recurrence at subsequent endoscopic follow-ups.ESD changed the histological staging of 44.5%of lesions.Immediate complications were observed in 9.9%of all ESD procedures.The median survival time was 69 months post-ESD.The mean age at death is 82.2 years old.CONCLUSION The study affirms the long-term efficacy and safety of ESD for gastric dysplasia and early neoplasia in Caucasian patients.展开更多
Type 2 diabetes mellitus is associated with a 2-4 times increased risk of cardiovascular(CV)disease.Glucagon-like polypeptide-1 receptor agonists(GLP1RA)and sodium-glucose cotransporter-2 inhibitors(SGLT2i)are two imp...Type 2 diabetes mellitus is associated with a 2-4 times increased risk of cardiovascular(CV)disease.Glucagon-like polypeptide-1 receptor agonists(GLP1RA)and sodium-glucose cotransporter-2 inhibitors(SGLT2i)are two important classes of drugs with CV benefits independent of their antihyperglycemic efficacy.The CV outcome trials of both GLP1RA and SGLT2i have demonstrated CV superiority/neutrality concerning major adverse CV events(MACE).While GLP1RAs have exhibited a significant reduction in ischemic stroke and myocardial infarction(MI),SGLT2i have demonstrated a uniformly significant reduction in hospitalization for heart failure(HF)as a class effect.The unique clinical benefits and the distinct but complementary mechanisms of action make the combination of these drugs a mechanistically sound one.Recent meta-analyses suggest an independent and additive benefit of combination therapy of GLP1RA/SGLT2i vs monotherapy.Zhu et al,in a recent issue of the World Journal of Diabetes,demonstrates a numerically lower hazard ratio(HR)for CV outcomes with combination therapy vs monotherapy with either agent,with a reduction in MACE compared to GLP1RA alone[HR=0.51,95%confidence interval(CI):0.16-1.65],or SGLT2i alone(HR=0.48,95%CI:0.15-1.54).The CV death rate was also lower with combination therapy compared to GLP1RA alone(HR=0.58,95%CI:0.08-3.39),or SGLT2i alone(HR=0.55,95%CI:0.07-3.25).Fatal and non-fatal MI and fatal and non-fatal stroke were reduced with combination therapy compared to GLP1RA alone(HR=0.45,95%CI:0.10-2.18 and HR=0.86,95%CI:0.12-6.23,respectively),or SGLT2i alone(HR=0.44,95%CI:0.09-2.10 and HR=0.74,95%CI:0.10-5.47,respectively).Hospitalization for HF was prevented with combination therapy compared to GLP1RA alone(HR=0.26,95%CI:0.03-1.88),or SGLT2i alone(HR=0.33,95%CI:0.04-2.53).They also demonstrated that GLP1RA or SGLT2i monotherapy may not provide significant improvement in CV death and recurrent MI in patients with prior MI or HF,proposing a role for combination therapy in this subgroup.Appropriate patient selection is vital to optimize CV risk reduction as well as the cost-effectiveness of this combination therapy.展开更多
A frequent cause of unplanned and costly outages in water-cooled nuclear power plants is the premature failure of the fuel rods due to excessive flow-induced vibration in the reactor core.Turbulence and unsteadiness i...A frequent cause of unplanned and costly outages in water-cooled nuclear power plants is the premature failure of the fuel rods due to excessive flow-induced vibration in the reactor core.Turbulence and unsteadiness in the coolant water flowing through the reactor core can cause excessive vibration of the fuel rods,which in turn can result in fretting wear that eventually leads to the fuel rod cladding perforation and subsequent failure.The economic burden of unplanned reactor outages has motivated extensive research into flow-induced vibration.This perspective article provides a brief summary of recent research on flow-induced vibration of cantilever rod systems,which are simplified paradigmatic test configurations that have been instrumental to advance the fundamental physical understanding of axial-flowinduced vibration problems,and have enabled the development of cost-effective numerical methodologies for the simulation of these problems in engineering,with particular application to nuclear reactor systems.This summary covers recent experimental and numerical studies,and includes a description of a novel non-contact Hall-effect-based measuring technique specifically developed to track the vibration of the cantilever rod with gas-liquid two-phase flows.The article concludes by highlighting promising avenues for future research.展开更多
文摘BACKGROUND Post-transplant tertiary hyperparathyroidism(PT-tHPT)is a well-recognized complication following kidney transplantation,characterized by persistent excessive secretion of parathyroid hormone(PTH)despite improved renal function.It is potentially associated with an increased risk of cardiovascular events,renal osteodystrophy,pathologic fractures,graft loss,and mortality.AIM To evaluate the incidence,risk factors,and outcomes of PT-tHPT amongst kidney transplant recipients.METHODS A total of 887 transplant recipients who underwent transplantation between 2000 and 2020 were evaluated.Univariable and multivariable logistic regression was performed to determine the predictors of tertiary hyperparathyroidism.Graft and recipient outcomes were assessed using multivariable Cox regression.A separate multivariable Cox regression was performed to determine the effect of treatment strategies on outcomes.RESULTS PT-tHPT,defined as elevated PTH(>65 ng/L)and persistent hypercalcemia(>2.60 mmol/L),was diagnosed in 14%of recipients.Risk factors for PT-tHPT included older age[odds ratio(OR)=1.36,P<0.001],Asian ethnicity(OR=0.33,P=0.006),total ischemia time(OR=1.03,P=0.048 per hour),pre-transplant serum calcium(OR=1.38,P<0.001)per decile increase,pre-transplant PTH level(OR=1.31,P<0.001)per decile increase,longer dialysis duration(OR=1.12,P=0.002)per year,history of acute rejection(OR=2.37,P=0.012),and slope of estimated glomerular filtration rate change(OR=0.91,P=0.001).There were a 3.4-fold higher risk of death-censored graft loss and a 1.9-fold greater risk of recipient death with PT-tHPT.The three treatment strategies of conservative management,calcimimetic and parathyroidectomy did not significantly change the graft or patient outcome.CONCLUSION Pretransplant elevated calcium and PTH levels,older age and dialysis duration are associated with PT-tHPT.While PT-tHPT significantly affects graft and recipient survival,the treatment strategies did not affect survival.
文摘BACKGROUND The use of induction immunosuppression agents has improved kidney transplant outcomes,but selecting the optimal agent remains a point of debate.AIM To compare the long-term outcomes of kidney transplant recipients receiving alemtuzumab vs basiliximab induction,focusing on graft function,acute rejection,infection,malignancy,post-transplant glomerulonephritis,and survival,using a propensity score matched cohort design.METHODS Kidney transplant recipients who received alemtuzumab or basiliximab induction from 2014 to 2019 across two nephrology centres in Northwest England were evaluated.Propensity score matching at a 1:1.5 ratio ensured comparability between cohorts.Baseline characteristics,immunosuppression regimens,and outcomes were analyzed.Linear,binary logistic and Cox proportional hazard regression models.RESULTS A total of 436 recipients were included,with a median follow-up of 5.2 years.The matched cohort(n=262)had a mean age of 51.1±13.5 years;39%were female and 92%were white.There was no significant difference in the cumulative incidence of acute rejection[odds ratio(OR)=2.10;95%CI:0.9-4.9;P=0.110].Compared with basiliximab,alemtuzumab was associated with lower estimated glomerular filtration rate at 12 months(-6.6 mL/minute/1.73 m2;95%CI:-10.5 to-2.7;P<0.001)and higher risks of cytomegalovirus viremia(OR=3.2;95%CI:1.6-6.5;P<0.001),BK viremia(OR=2.4;95%CI:1.1-5.5;P=0.02),post-transplant malignancy(OR=6.2;95%CI:1.6-29.9;P=0.013),and death-censored graft loss(hazard ratio=3.6;95%CI:1.2-11.4;P=0.03).No significant differences were observed in post-transplant glomerulonephritis or recipient mortality.CONCLUSION In this propensity score-matched analysis,alemtuzumab induction was associated with lower graft function at 12 months and higher risks of viral infection,post-transplant malignancy,and graft loss compared with basiliximab.These findings highlight the need for further studies to confirm the long-term safety and effectiveness of alemtuzumab in kidney transplantation.
文摘Diabetes mellitus represents a major global health issue,driving the need for noninvasive alternatives to traditional blood glucose monitoring methods.Recent advancements in wearable technology have introduced skin-interfaced biosensors capable of analyzing sweat and skin biomarkers,providing innovative solutions for diabetes diagnosis and monitoring.This review comprehensively discusses the current developments in noninvasive wearable biosensors,emphasizing simultaneous detection of biochemical biomarkers(such as glucose,cortisol,lactate,branched-chain amino acids,and cytokines)and physiological signals(including heart rate,blood pressure,and sweat rate)for accurate,personalized diabetes management.We explore innovations in multimodal sensor design,materials science,biorecognition elements,and integration techniques,highlighting the importance of advanced data analytics,artificial intelligence-driven predictive algorithms,and closed-loop therapeutic systems.Additionally,the review addresses ongoing challenges in biomarker validation,sensor stability,user compliance,data privacy,and regulatory considerations.A holistic,multimodal approach enabled by these next-generation wearable biosensors holds significant potential for improving patient outcomes and facilitating proactive healthcare interventions in diabetes management.
文摘Monogenic diabetes is a heterogeneous disorder characterized by hyperglycemia arising from defects in a single gene.Maturity-onset diabetes of the young(MODY)is the most common type with 14 subtypes,each linked to specific mutations affecting insulin synthesis,secretion and glucose regulation.Common traits across MODY subtypes include early-onset diabetes,a family history of autosomal dominant diabetes,lack of features of insulin resistance,and absent islet cell autoimmunity.Many cases are misdiagnosed as type 1 and type 2 diabetes mellitus.Biomarkers and scoring systems can help identify candidates for genetic testing.GCK-MODY,a common subtype,manifests as mild hyperglycemia and doesn’t require treatment except during pregnancy.In contrast,mutations in HNF4A,HNF1A,and HNF1B genes lead to progressive beta-cell failure and similar risks of complications as type 2 diabetes mellitus.Neonatal diabetes mellitus(NDM)is a rare form of monogenic diabetes that usually presents within the first six months.Half of the cases are lifelong,while others experience transient remission.Permanent NDM is most commonly due to activating mutations in genes encoding the adenosine triphosphate-sensitive potassium channel(KCNJ11 or ABCC8)and can be transitioned to sulfonylurea after confirmation of diagnosis.Thus,in many cases,monogenic diabetes offers an opportunity to provide precision treatment.The scope has broadened with next-generation sequencing(NGS)technologies,replacing older methods like Sanger sequencing.NGS can be for targeted gene panels,whole-exome sequencing(WES),or whole-genome sequencing.Targeted gene panels offer specific information efficiently,while WES provides comprehensive data but comes with bioinformatic challenges.The surge in testing has also led to an increase in variants of unknown significance(VUS).Deciding whether VUS is disease-causing or benign can be challenging.Computational models,functional studies,and clinical knowledge help to determine pathogenicity.Advances in genetic testing technologies offer hope for improved diagnosis and personalized treatment but also raise concerns about interpretation and ethics.
文摘BACKGROUND Metabolic dysfunction-associated fatty liver disease(MAFLD)and type 2 diabetes mellitus(T2DM)are independent risk factors for the development of cardiovascular disease(CVD)and an exaggerated CVD risk is expected when both diseases co-exist.Therefore,thorough risk stratification is important to inform better clinical practice decisions based on good quality evidence for patient with MAFLD and T2DM.AIM To identify the CVD and cardiovascular event(CVE)risk in a systematic review when MAFLD and T2DM co-exist to inform better clinical practice decisions.METHODS A systematic review was performed by compiling data by searching PubMed,EMBASE and Cochrane Library databases.Quality appraisal of retrieved studies and the meta-analysis were performed using Joanna Briggs Institute(JBI)tool and RevMan 5.4 software respectively.The effect indicators for CVE and CVD risk were expressed as odds ratios(OR)and 95%CI with P-values<0.05 as significant.RESULTS Fourteen(5 cohort and 9 cross-sectional)studies with 370013 participants were included in this review.The metaanalysis of CVE showed that the risk of CVE in T2DM was higher in the MAFLD group when compared to the non-MAFLD group[OR 1.28(95%CI,1.04-1.56)P=0.02]with follow up duration ranging between 5-6 years.The prevalence of CVD in the metanalysis of cross-sectional studies was found to be higher[OR 1.47(95%CI,1.21-1.78)P=0.0001]in T2DM with MAFLD when compared to T2DM without MAFLD.Significant heterogeneity exists due to variations in study design,methodologies,and MAFLD diagnostic criteria,which may have influenced the study's findings.CONCLUSION The presence of MAFLD in T2DM increased the risk of CVE.The prevalence of CVD is higher in T2DM with MAFLD as compared to T2DM without MAFLD.Large well-designed multicentric long-term prospective studies are necessary to appropriately risk stratify the cardiovascular effect of the MAFLD in T2DM patients.
文摘BACKGROUND The incidence of type 2 diabetes mellitus(T2DM)in children and adolescents is increasing,yet there is limited information on the available pharmacological interventions to combat T2DM and prevent associated comorbidities.AIM To assess the effectiveness of current pharmacological treatments in managing T2DM in children and adolescents.The protocol of the study was registered in PROSPERO(CRD42022382165).METHODS Searches were performed in PubMed,EMBASE,Scopus,and ClinicalTrials.gov for publications between 1990 to September 2024 without language restrictions.Randomized control trials(RCTs)of pharmacotherapy in children and adolescents with T2DM(aged<19 years)were included.The primary outcome was a change in glycated hemoglobin(HbA1c)from baseline to follow-up.Secondary outcomes were changes in body weight,body mass index(BMI),total cholesterol,triglycerides,high density lipoprotein,and low-density lipoprotein from baseline,and incidence of adverse events during study periods.Screening,full-text review,data extraction,and assessments of risk of bias were done by two reviewers.Conflicts on each step were resolved by a third reviewer.Data analysis was performed using Review Manager Version 6.5(RevMan 6.5)and‘R’software via RStudio,‘meta’and‘netmeta’.RESULTS A total of 12 studies having low to moderate risk of bias with 1658 participants,and follow-up duration 12-52 weeks were included.In our network meta-analysis,compared to control(s),the reduction of HbA1c was sig-nificantly larger for dulaglutide[mean difference(MD),95%confidence interval:-1.20,-2.12 to-0.28],followed by dapagliflozin(-0.94,-1.44 to-0.44),liraglutide(-0.91,-1.37 to-0.45),empagliflozin(-0.87,-1.40 to-0.34),exenatide(-0.59,-1.07 to-0.11)and linagliptin(-0.45,-0.87 to-0.02)while other drugs had little or no effect.While liraglutide was associated with a change in body weight[MD-2.41(-4.68,-0.14)kg],no other drug treatment was associated with significant changes in body weight,BMI,and lipids.Apart from level 1 hypoglycemia with liraglutide[risk difference(RD):0.20,0.04-0.37]and minor adverse events with dulaglutide(RD:0.24,0.08-0.40),no other treatment was associated with excess risk of hypoglycemia or minor or major adverse events.CONCLUSION Pharmacotherapy of T2DM with dulaglutide,dapagliflozin,liraglutide,empagliflozin,exenatide,and linagliptin in children is associated with modest reduction of HbA1c.Larger RCTs with longer follow-up durations are needed to guide better therapeutic decision making.
文摘Use of immunomodulating agents to prevent the progression of autoimmuneβ-cell damage leading to type 1 diabetes mellitus(T1DM)is an interesting area for research.These include non-specific anti-inflammatory agents,immunologic vaccination and anti-inflammatory agents targeting specific immune cells or cytokines.Teplizumab is an anti-CD3-molecule that binds to and leads to the disappearance of the CD3/TCR complex and rendering the T cell anergic to its target antigen.Preclinical and clinical trials have demonstrated its efficacy in reducing the decline in serum C-peptide levels and the need for insulin therapy if used early in the disease process of T1DM.The benefits have been apparent as early as six months to as long as seven years after therapy.It has recently been approved by the Food and Drug Administration to delay the onset of clinical(stage 3)type 1 diabetes in children above 8 years of age.In their recent metaanalysis published in the World Journal of Diabetes,Ma et al found that those in the teplizumab treatment group have a greater likelihood of reduction in insulin use,change in C-peptide response,and better glycemic control compared to the control group with a good safety profile.However,all the included randomized control trials have been conducted in high-income countries.High cost of therapy and unknown utility of the molecule in stage 3 disease limit its widespread use.
基金supported by the National Natural Science Foundation of China(Grant Nos.:82204340,82173954,and 82073815)the Natural Science Foundation of Jiangsu Province,China(Grant No.:BK20221048)+1 种基金the Jiangsu Funding Program for Excellent Postdoctoral Talent,China(Grant No.:2022ZB295)Key Laboratory Project of Quality Control of Chinese Herbal Medicines and Decoction Pieces,Gansu Institute for Drug Control,China(Grant No.:2024GSMPA-KL02).
文摘Bacterial infection is a major threat to global public health,and can cause serious diseases such as bacterial skin infection and foodborne diseases.It is essential to develop a new method to rapidly diagnose clinical multiple bacterial infections and monitor food microbial contamination in production sites in real-time.In this work,we developed a 4-mercaptophenylboronic acid gold nanoparticles(4-MPBA-AuNPs)-functionalized hydrogel microneedle(MPBA-H-MN)for bacteria detection in skin interstitial fluid.MPBA-H-MN could conveniently capture and enrich a variety of bacteria within 5 min.Surface enhanced Raman spectroscopy(SERS)detection was then performed and combined with machine learning technology to distinguish and identify a variety of bacteria.Overall,the capture efficiency of this method exceeded 50%.In the concentration range of 1×10_(7) to 1×10^(10) colony-forming units/mL(CFU/mL),the corresponding SERS intensity showed a certain linear relationship with the bacterial concentration.Using random forest(RF)-based machine learning,bacteria were effectively distinguished with an accuracy of 97.87%.In addition,the harmless disposal of used MNs by photothermal ablation was convenient,environmentally friendly,and inexpensive.This technique provided a potential method for rapid and real-time diagnosis of multiple clinical bacterial infections and for monitoring microbial contamination of food in production sites.
基金supported by the UK EPSRC(grant EP/T024607/1,‘Coat IN’)provided by the Henry Royce Institute for Advanced Materials,funded through the UK EPSRC grants EP/R00661X/1,EP/S019367/1,EP/P025021/1 and EP/P025498/1support from the University of Manchester and Chinese Scholarship Council for his Ph D studies。
文摘Electrolyte selection for Plasma Electrolytic Oxidation(PEO)of magnesium is important as this determines composition,morphology and properties of resultant coatings that are urgently sought after for protection of Mg alloys from corrosion and wear in harsh environments.However,electrolyte design is often performed heuristically,which hampers the development and optimisation of new PEO processes.Here,we attempt to achieve a mechanistic understanding of electrochemical and microstructural aspects of anodic films evolution at the prebreakdown stages of PEO treatments of magnesium in aqueous alkaline solutions of NaAlO_(2),Na_(3)PO_(4),Na F and Na_(2)SiO_(3).Systematic studies have shown that magnesium self-passivation by MgO/Mg(OH)_(2)can be compromised by both chemical and mechanical instabilities developed due to side effects of anodic reactions.Stable initiation of PEO process requires maintaining surface passivity in a wide range of p H,which can be achieved only by combining self-depositing passivators with those binding dissolved magnesium into insoluble compounds.
基金the financial support given by EPSRC to the Grant LOFAMO(No.EP/X023281/1)the Basque Government for the financial support given from Elkartek Program to the Project FRONTIERS 2022—Superficies Multifuncionales en la Frontera del Conocimiento(No.KK2022/00109)。
文摘Machine Hammer Peening(MHP)is an emergent treatment that induces high compressive Residual Stresses(RS)which can enhance the in-service performance of components.This paper studies the use of small diameter MHP tools to improve the Surface Integrity(SI)of the nickel-based alloy Inconel 718 used in critical aero-engine components.Complementarily,the relaxation of RS is analyzed by in-situ annealing tests at in-service temperature combined with X-ray diffraction measurement.For this purpose,age hardened Inconel 718 discs were turned as reference condition,and then a pneumatic MHP tool was used under different conditions:two tool diameters(4 mm and 12 mm),feed rates(2.5 m/min and 5.0 m/min)and stepover distances(0.07 mm and 0.35 mm).Subsequently,surface topography characterization,RS measurements,nanoindentation tests,and microstructural observations were conducted.The in-situ annealing tests were done in the X-ray diffractometer at 550°C for exposure periods from 0 to 20 h.The results demonstrate that 4 mm diameter tools generate smooth surfaces and induce significant compressive RS within a0.5 mm thick layer.Residual stresses are relaxed,but they remain compressive even after a long thermal exposure.The microstructure of the surface layer(<10–15μm)was affected by the preceding turning operation,but importantly,MHP did not induce additional damage.
基金the financial support received from the UK Engineering and Physical Sciences Research Council(EPSRC)through project grants EP/W010089/1 and EP/T005254/1.
文摘With the generation of both localised thermal and vibration in incremental sheet forming(ISF)by novel tool designs,rotational vibration assisted ISF(RV-ISF)can achieve significant force reduction and material softening.However,the combined thermal and vibration softening in RV-ISF is unclear.By evaluating the similarities and differences of friction stir ISF(FS-ISF)and RV-ISF,this study develops a novel approach to decouple and quantify the thermal and vibration softening effects in RV-ISF of AZ31B-H24,providing new insights into underlying thermal and vibration softening mechanism.Experimental results reveal that in RV-ISF of AZ31B-H24 the thermal softening due to frictional heating dominates with 45∼65%of softening,while the vibration effect only contributes up to 15%of softening,from the conventional ISF,depending on the tool designs and tool rotational speed.The double-offset tool(T2)produces greater vibration softening than the three-groove tool(T3)owing to the higher vibration amplitude of the T2 tool.An increase in tool rotational speed primarily enhances thermal softening with only marginal changes to the vibration effect.Microstructural analysis suggests that with average grain size of 0.94μm at the top layer,RV-ISF with T3 and 3000 rpm is more effective for microstructure refinement than that by FS-ISF,especially on the tool-sheet contact surface,which confirms the occurrence of surface shearing.This refinement is a result of the reduced recrystallisation degree,71.8%at the top bottom layer.Compared with FS-ISF,RV-ISF can lead to not only higher geometrically necessary dislocation density,but also higher fraction of low-angle grain boundaries,indicating that softening mechanism due to localised vibration effect is resulted from the enhanced rearrangement and annihilation of dislocations.These findings contribute to new understanding of the thermal and vibration softening effects in RV-ISF of AZ31B-H24 and offer a theoretical foundation for the tool design and process optimisation.
基金supported by the Henry Royce Institute for Advanced Materials,funded through Engineering and Physical Sciences Research Council(EPSRC)grants EP/R00661X/1,EP/S019367/1,EP/P025021/1,and EP/P025498/1.
文摘Liquefied natural gas storage and transportation as well as space propulsion systems have sparked inter-est in the martensitic transformation and behaviours of 316 L stainless steels(SS)under ultra-cryogenic deformation.In this study,high-resolution transmission electron microscopy(HRTEM)and molecular dy-namics(MD)simulations were used to investigate the atomic arrangements and crystalline defects of deformation-induced γ-austenite→ε-martensite→α'-martensite and γ→α'martensitic transforma-tions in 316 L SS at 15 and 173 K.Theγ→εtransformation involves the glide of Shockley partial dislocations on(111)γplanes without a change in atomic spacing.The formation of anα'inclusion in a singleε-band is achieved by a continuous lattice distortion,accompanied by the formation of a tran-sition zone ofα'and the expansion of the average atomic spacings due to dislocation shuffling.Asα'grows further intoγ,the orientation relationship(OR)of theα'changes by lattice bending.This pro-cess follows the Bogers-Burgers-Olson-Cohen model despite it not occurring on intersecting shear bands.Stacking faults and twins can also serve as nucleation sites forα'at 173 K.We also found that direct transformation of γ→α'occurs by the glide of √6aγ[11(2)]/12 dislocations on every(111)γplane with misfit dislocations.Overall,this study provides,for the first time,insights into the atomic-scale mech-anisms of various two-step and one-step martensitic transformations induced by cryogenic deformation and corresponding local strain,enhancing our understanding of the role of martensitic transformation under ultra-cryogenic-temperature deformation in controlling the properties.
基金supported by Science and Technology Major Project of Hubei Province in China(No.2021AFB001)。
文摘In laser wakefield acceleration,injecting an external electron beam at a certain energy is a promising approach for achieving a high-quality electron beam with low energy spread and low emittance.In this paper,the process of laser wakefield acceleration with an external injection at 10 pC has been studied in simulations.A Bayesian optimization method is used to optimize the key laser and plasma parameters so that the electron beam is accelerated to the expected energy with a small emittance and energy spread growth.The effect of the rising edge of the plasma on the transverse properties of the electron beam is simulated and optimized in order to ensure that the external electron beam is injected into the plasma without significant emittance growth.Finally,a high-quality electron beam with an energy of 1.5 GeV,a normalized transverse emittance of 0.5 mm·mrad and a relative energy spread of 0.5%at 10 pC is obtained.
基金support from China Scholarship Council(CSC)(202406440073).
文摘Accurate prediction of pure component physiochemical properties is crucial for process integration, multiscale modelling, and optimization. In this work, an enhanced framework for pure component property prediction by using explainable machine learning methods is proposed. In this framework, the molecular representation method based on the connectivity matrix effectively considers atomic bonding relationships to automatically generate features. The supervised machine learning model random forest is applied for feature ranking and pooling. The adjusted R^(2) is introduced to penalize the inclusion of additional features, providing an assessment of the true contribution of features. The prediction results for normal boiling point (T_(b)), liquid molar volume (L_(mv)), critical temperature (T_(c)) and critical pressure (P_(c)) obtained using Artificial Neural Network and Gaussian Process Regression models confirm the accuracy of the molecular representation method. Comparison with GC based models shows that the root-mean-square error on the test set can be reduced by up to 83.8%. To enhance the interpretability of the model, a feature analysis method based on Shapley values is employed to determine the contribution of each feature to the property predictions. The results indicate that using the feature pooling method reduces the number of features from 13316 to 100 without compromising model accuracy. The feature analysis results for Tb, Lmv, Tc, and Pc confirms that different molecular properties are influenced by different structural features, aligning with mechanistic interpretations. In conclusion, the proposed framework is demonstrated to be feasible and provides a solid foundation for mixture component reconstruction and process integration modelling.
基金supported by the National Natural Science Foundation of China(No.42377095)the Open Research Fund Program of Plateau Atmosphere and Environment Key Laboratory of Sichuan Province(No.PAEKL-2024-K01)Xianyang Key Research and Development Program(No.L2022ZDYFSF040).
文摘Tropospheric ozone pollution has been worsened over most regions of China,adversely affecting human health and ecosystems.The long-term ozone concentration depends largely upon atmospheric circulations.Here,we conducted meteorological adjustment to quantitatively assess the influences of meteorological factors on the ozone evolution in China's seven city clusters during thewarm season(April to October)from 2013 to 2020.Our analysis indicated that northern and eastern regions experienced ozone increases driven by emission changes.Southern regions,particularly the Pearl River Delta(PRD),exhibited ozone rise primarily due to meteorological conditions despite emission changes.In the Sichuan Basin(SCB)and Central Yangtze River Plain(CYP),where ozone levels decreased,meteorological conditions played a significant role in suppressing the ascent of ozone.Empirical orthogonal functions(EOF)analyses suggested that the spatiotemporal trend ofmeteorologyassociated ozone was strongly correlated with the variation of East Asian Trough(EAT),South Asian High(SAH)and the western Pacific subtropical high(WPSH).The top three EOF patterns explained 33.4%,21.8%,and 16.0%of the total variance inmeteorology-associated ozone.Absolute principal component scores-multiple linear regression(APCS-MLR)analyse quantitatively identified that enhanced EAT and SAH with a northward location of WPSH were favourable to surface ozone formation in central and eastern regions,but unfavourable to ozone formation in edge regions such as SCB.
基金supported by the National Natural Science Foundation of China under Grants Nos.62431014 and 62271310the Fundamental Research Funds for the Central Universities of China。
文摘The advent of 6G wireless networks promises unprecedented connectivity,supporting ultra-high data rates,low latency,and massive device connectivity.However,these ambitious goals introduce significant challenges,particularly in channel estimation due to complex and dynamic propagation environments.This paper explores the concept of channel knowledge maps(CKMs)as a solution to these challenges.CKMs enable environment-aware communications by providing location-specific channel information,reducing reliance on real-time pilot measurements.We categorize CKM construction techniques into measurement-based,model-based,and hybrid methods,and examine their key applications in integrated sensing and communication(ISAC)systems,beamforming,trajectory optimization of unmanned aerial vehicles(UAVs),base station(BS)placement,and resource allocation.Furthermore,we discuss open challenges and propose future research directions to enhance the robustness,accuracy,and scalability of CKM-based systems in the evolving 6G landscape.
基金supported by the National Natural Science Foundation of China(52375204)Shaanxi Provincial Science and Technology Innovation Team(2024RS-CXTD-63)+4 种基金Xianyang 2023 Key Research and Development Plan(L2023-ZDYF-QYCX-009)the Fundamental Research Funds for the Central Universities(D5000230356)2024“Double First-Class University”Construction Special Fund Project(0604024GH0201332,0604024SH0201332)Zhiyuan Laboratory(NO.ZYL2024007)Horizon Europe Framework Programme(101086071-CUPOLA).
文摘Conductive hydrogels have garnered widespread attention as a versatile class of flexible electronics.Despite considerable advancements,current methodologies struggle to reconcile the fundamental trade-off between high conductivity and effective absorption-dominated electromagnetic interference(EMI)shielding,as dictated by classical impedance matching theory.This study addresses these limitations by introducing a novel synthesis of aramid nanofiber/MXene-reinforced polyelectrolyte hydrogels.Leveraging the unique properties of polyelectrolytes,this innovative approach enhances ionic conductivity and exploits the hydration effect of hydrophilic polar groups to induce the formation of intermediate water.This critical innovation facilitates polarization relaxation and rearrangement in response to electromagnetic fields,thereby significantly enhancing the EMI shielding effectiveness of hydrogels.The electromagnetic wave attenuation capacity of these hydrogels was thoroughly evaluated across both X-band and terahertz band frequencies,with further investigation into the impact of varying water content states-hydrated,dried,and frozen-on their electromagnetic properties.Moreover,the hydrogels exhibited promising capabilities beyond mere EMI shielding;they also served effectively as strain sensors for monitoring human motions,indicating their potential applicability in wearable electronics.This work provides a new approach to designing multifunctional hydrogels,advancing the integration of flexible,multifunctional materials in modern electronics,with potential applications in both EMI shielding and wearable technology.
文摘BACKGROUND Endoscopic submucosal dissection(ESD)is increasingly used to treat gastric dysplasia and early neoplasia in the West.Unlike Eastern countries,data for Caucasian patients in the United Kingdom is limited due to its limited implementation in a few tertiary centres.AIM To evaluate the outcomes of ESD on gastric dysplasia and neoplasia in Caucasian patients.METHODS Our ten-year retrospective study at a single tertiary centre included data spanning from May 2012 to July 2023.The efficacy of ESD on gastric dysplasia and early neoplasia was measured using parameters set out by the National Institute for Health and Care Excellence,which include en-bloc and curative resection(CR)rates,local recurrence and survival rates.RESULTS ESD was attempted on 111 lesions in 93 patients.95.0%of completed procedures achieved endoscopic clearance.74.3%were en-bloc resections and the rest were hybrid ESD with piecemeal resections.In all,34.7%achieved histological CR.Overall,disease recurrence was 10.9%at latest follow-up(63 months,median follow-up).Importantly 100%of lesions in the CR group showed no disease recurrence at subsequent and latest follow-up.In the Indeterminate and Non-CR group,18.8%of lesions showed disease recurrence at subsequent endoscopic follow-ups.ESD changed the histological staging of 44.5%of lesions.Immediate complications were observed in 9.9%of all ESD procedures.The median survival time was 69 months post-ESD.The mean age at death is 82.2 years old.CONCLUSION The study affirms the long-term efficacy and safety of ESD for gastric dysplasia and early neoplasia in Caucasian patients.
文摘Type 2 diabetes mellitus is associated with a 2-4 times increased risk of cardiovascular(CV)disease.Glucagon-like polypeptide-1 receptor agonists(GLP1RA)and sodium-glucose cotransporter-2 inhibitors(SGLT2i)are two important classes of drugs with CV benefits independent of their antihyperglycemic efficacy.The CV outcome trials of both GLP1RA and SGLT2i have demonstrated CV superiority/neutrality concerning major adverse CV events(MACE).While GLP1RAs have exhibited a significant reduction in ischemic stroke and myocardial infarction(MI),SGLT2i have demonstrated a uniformly significant reduction in hospitalization for heart failure(HF)as a class effect.The unique clinical benefits and the distinct but complementary mechanisms of action make the combination of these drugs a mechanistically sound one.Recent meta-analyses suggest an independent and additive benefit of combination therapy of GLP1RA/SGLT2i vs monotherapy.Zhu et al,in a recent issue of the World Journal of Diabetes,demonstrates a numerically lower hazard ratio(HR)for CV outcomes with combination therapy vs monotherapy with either agent,with a reduction in MACE compared to GLP1RA alone[HR=0.51,95%confidence interval(CI):0.16-1.65],or SGLT2i alone(HR=0.48,95%CI:0.15-1.54).The CV death rate was also lower with combination therapy compared to GLP1RA alone(HR=0.58,95%CI:0.08-3.39),or SGLT2i alone(HR=0.55,95%CI:0.07-3.25).Fatal and non-fatal MI and fatal and non-fatal stroke were reduced with combination therapy compared to GLP1RA alone(HR=0.45,95%CI:0.10-2.18 and HR=0.86,95%CI:0.12-6.23,respectively),or SGLT2i alone(HR=0.44,95%CI:0.09-2.10 and HR=0.74,95%CI:0.10-5.47,respectively).Hospitalization for HF was prevented with combination therapy compared to GLP1RA alone(HR=0.26,95%CI:0.03-1.88),or SGLT2i alone(HR=0.33,95%CI:0.04-2.53).They also demonstrated that GLP1RA or SGLT2i monotherapy may not provide significant improvement in CV death and recurrent MI in patients with prior MI or HF,proposing a role for combination therapy in this subgroup.Appropriate patient selection is vital to optimize CV risk reduction as well as the cost-effectiveness of this combination therapy.
文摘A frequent cause of unplanned and costly outages in water-cooled nuclear power plants is the premature failure of the fuel rods due to excessive flow-induced vibration in the reactor core.Turbulence and unsteadiness in the coolant water flowing through the reactor core can cause excessive vibration of the fuel rods,which in turn can result in fretting wear that eventually leads to the fuel rod cladding perforation and subsequent failure.The economic burden of unplanned reactor outages has motivated extensive research into flow-induced vibration.This perspective article provides a brief summary of recent research on flow-induced vibration of cantilever rod systems,which are simplified paradigmatic test configurations that have been instrumental to advance the fundamental physical understanding of axial-flowinduced vibration problems,and have enabled the development of cost-effective numerical methodologies for the simulation of these problems in engineering,with particular application to nuclear reactor systems.This summary covers recent experimental and numerical studies,and includes a description of a novel non-contact Hall-effect-based measuring technique specifically developed to track the vibration of the cantilever rod with gas-liquid two-phase flows.The article concludes by highlighting promising avenues for future research.
