高压电缆长期过热可能导致绝缘热击穿,进而影响电网的稳定性。然而,当前研究主要集中在传统预测模型上,忽略了温度数据的复杂性和动态特征。为了解决此问题,提出一种基于多尺度Patch与卷积交互的电缆温度预测模型(MSP-CI)。首先,采用通...高压电缆长期过热可能导致绝缘热击穿,进而影响电网的稳定性。然而,当前研究主要集中在传统预测模型上,忽略了温度数据的复杂性和动态特征。为了解决此问题,提出一种基于多尺度Patch与卷积交互的电缆温度预测模型(MSP-CI)。首先,采用通道重组采样方法降低输入维度,并构建多尺度Patch分支结构,以实现复杂时间序列的解耦;其次,结合序列分解与卷积交互策略,分别提取粗粒度Patch的宏观信息与细粒度Patch的微观信息;最后,构建注意力融合模块,以动态平衡宏观与微观信息的权重,并得到最终的预测结果。在真实高压电缆温度数据集上的实验结果表明,MSP-CI相较于TimeMixer、PatchTST(Patch Time Series Transformer)和MSGNet(Multi-Scale interseries Graph Network)等基线模型,在均方误差(MSE)上下降了7.02%~34.87%,在平均绝对误差(MAE)上下降了5.15%~32.04%。可见,MSP-CI能有效提升电缆温度预测的准确率,为电力调度运行提供依据。展开更多
光伏功率日前预测的准确性对电网的能源管理至关重要。针对光伏功率随机性及波动性大、预测精度不高的问题,文章提出一种基于PatchTST-STL模型的光伏发电功率日前预测方法。该方法通过引入时序块和季节趋势分解(seasonal and trend deco...光伏功率日前预测的准确性对电网的能源管理至关重要。针对光伏功率随机性及波动性大、预测精度不高的问题,文章提出一种基于PatchTST-STL模型的光伏发电功率日前预测方法。该方法通过引入时序块和季节趋势分解(seasonal and trend decomposition using loess,STL)改进Transformer的输入和架构,将每个时间步作为1个令牌(Token)改进为每个时序块(Patch)作为1个令牌,使得局部依赖关系被保留在1个令牌内,以提升局部模式捕捉能力,同时利用Transformer多头自注意力机制抽取序列长期依赖关系。考虑到光伏序列的模式复杂,采用STL对多变量光伏序列进行处理,分离出趋势、周期和残差部分,作为独立通道输入。使用灰狼优化算法(grey wolf optimizer,GWO)对模型超参数中时序块大小进行优化,以实现算法快速收敛。在澳大利亚沙漠知识太阳能中心数据集的实验结果表明,所提算法与Informer相比,平均绝对误差(mean absolute error,MAE)和均方根误差(root mean square error,RMSE)平均分别降低了36.7%和11.7%;与Transformer相比,MAE和RMSE平均分别降低了57.6%和30.9%。展开更多
Microneedles(MNs)have been extensively investigated for transdermal delivery of large-sized drugs,including proteins,nucleic acids,and even extracellular vesicles(EVs).However,for their sufficient skin penetration,con...Microneedles(MNs)have been extensively investigated for transdermal delivery of large-sized drugs,including proteins,nucleic acids,and even extracellular vesicles(EVs).However,for their sufficient skin penetration,conventional MNs employ long needles(≥600μm),leading to pain and skin irritation.Moreover,it is critical to stably apply MNs against complex skin surfaces for uniform nanoscale drug delivery.Herein,a dually amplified transdermal patch(MN@EV/SC)is developed as the stem cell-derived EV delivery platform by hierarchically integrating an octopusinspired suction cup(SC)with short MNs(≤300μm).While leveraging the suction effect to induce nanoscale deformation of the stratum corneum,MN@EV/SC minimizes skin damage and enhances the adhesion of MNs,allowing EV to penetrate deeper into the dermis.When MNs of various lengths are applied to mouse skin,the short MNs can elicit comparable corticosterone release to chemical adhesives,whereas long MNs induce a prompt stress response.MN@EV/SC can achieve a remarkable penetration depth(290μm)for EV,compared to that of MN alone(111μm).Consequently,MN@EV/SC facilitates the revitalization of fibroblasts and enhances collagen synthesis in middle-aged mice.Overall,MN@EV/SC exhibits the potential for skin regeneration by modulating the dermal microenvironment and ensuring patient comfort.展开更多
The double-sided lapping process is extensively employed in the manufacturing of wafers,optical windows,and seal rings due to its high efficiency and ability to achieve precise flatness.However,limited research has ex...The double-sided lapping process is extensively employed in the manufacturing of wafers,optical windows,and seal rings due to its high efficiency and ability to achieve precise flatness.However,limited research has explored the thickness uniformity among different workpieces after double-sided lapping,and the underlying mechanism remains unclear.To address the demand for higher precision,this paper first analyzed the relative kinematic model between the workpiece and the lapping plate to clarify the causes of thickness variations among workpieces after double-sided lapping.Subsequently,a finite element method(FEM)model was developed to account for the pressure distribution on the workpiece surfaces at the initial stage of the process.The results indicate that the number of workpieces influences the final thickness variation.Then,various sets of thin copper plates with different thicknesses were lapped,and the findings revealed that five copper plates processed simultaneously exhibited more uniform thickness compared to the three plates.The experimental results align well with the theoretical analysis.Ultimately,a thickness variation of less than 6μm was achieved on five copper plates measuringΦ100×2.9 mm.This study presents a comprehensive analysis of the mechanisms influencing thickness uniformity in the double-sided lapping process and provides practical guidelines for optimizing the process to achieve stringent precision standards in industrial applications.展开更多
Using abundant saline water for electrolysis,rather than limited freshwater,presents a promising technique for generating clean hydrogen energy.However,high concentration of corrosive chloride ions in saline water pos...Using abundant saline water for electrolysis,rather than limited freshwater,presents a promising technique for generating clean hydrogen energy.However,high concentration of corrosive chloride ions in saline water poses a great challenge in the stability of anode.In this study,we present a straightforward strategy to protect the anode from corrosion by patching the catalyst layer through a treatment of the anode with a sodium sulfide(Na2S) solution followed by electrochemical activation.The rapid sulfurization of the Ni electrode in Na2S results in the formation of a Na2S layer,which can subsequently be converted to NiOOH upon electrochemical activation,thereby shielding the inner Ni electrode from corrosion.The as-prepared electrode (P-NiFe-LDH/Ni) based on the strategy demonstrated stability over 3,500 h at an industrial current density of 0.5 A cm^(-2)in a 0.5 M NaCl and 1 M KOH solution.This study presents an effective strategy to significantly enhance the stability of anodes for saline water electrolysis by effectively patching the cracks in the catalyst layer.展开更多
Bio-magnesium(Mg)alloys exhibit excellent biocompatibility and biodegradability,making them highly promising for implant applications.However,their limited strength-ductility balance remains a critical challenge restr...Bio-magnesium(Mg)alloys exhibit excellent biocompatibility and biodegradability,making them highly promising for implant applications.However,their limited strength-ductility balance remains a critical challenge restricting widespread use.In this study,ultra-fine-grained and homogeneous Mg alloys were fabricated using double-sided friction stir processing(DS-FSP)with liquid CO_(2) rapid cooling,leading to a significant enhancement in the strength-ductility synergy of the stirred zone.The results demonstrate that DS-FSP samples exhibit simultaneous improvements in ultimate tensile strength(UTS)and elongation,reaching 334.1±15 MPa and 28.2±7.3%,respectively.Compared to the non-uniform fine-grained microstructure obtained through single-sided friction stir processing,DS-FSP generates a uniform ultra-fine-grained structure,fundamentally altering the fracture behavior and mechanisms of Mg alloys.The DS-FSP samples exhibit irregular fracture patterns due to variations in basal slip system activation among different grains.In contrast,single-sided friction stir processing samples,characterized by a fine-grained yet heterogeneous microstructure,display flat shear fractures dominated by high-density dislocation initiation induced by twin formation,with fracture propagation dictated by the non-uniform texture.By achieving an ultra-fine grain size and homogeneous texture,DS-FSP effectively modifies the fracture mechanisms,thereby enhancing the strength-ductility balance of bio-magnesium alloys.展开更多
Objective:To evaluate the intervention effect of childlike nursing combined with Chinese herbal patching on pediatric bronchopneumonia.Methods:1036 children with bronchopneumonia(one family member included for each ch...Objective:To evaluate the intervention effect of childlike nursing combined with Chinese herbal patching on pediatric bronchopneumonia.Methods:1036 children with bronchopneumonia(one family member included for each child)who were admitted to the hospital between January 2024 and June 2024 were selected and randomly divided into two groups using a random number table.The combined group received childlike nursing combined with Chinese herbal patching,while the control group received routine nursing.Symptom recovery time,treatment compliance,inflammatory factor levels,quality of life of the children,and family satisfaction were compared between the two groups.Results:The symptom recovery time in the combined group was shorter than that in the control group,treatment compliance was higher,inflammatory factor levels after intervention were lower,quality of life scores of the children were lower,and family satisfaction was higher(P<0.05).Conclusion:The implementation of childlike nursing combined with Chinese herbal patching for children with bronchopneumonia can shorten their symptom recovery time,significantly improve treatment compliance and quality of life,reduce inflammatory reactions,and achieve high satisfaction among family members.展开更多
The alpine grassland vegetation on the Qinghai-Tibet Plateau is composed of plant patches in varied sizes.It remains uncertain whether vegetation recovery following grazing exclusion(GE)in degraded grasslands is drive...The alpine grassland vegetation on the Qinghai-Tibet Plateau is composed of plant patches in varied sizes.It remains uncertain whether vegetation recovery following grazing exclusion(GE)in degraded grasslands is driven by increases in patches number(NP),patch size(PS),or both.We based our predictions on two hypotheses:GE intensifies plant competition,and facilitation prevails near patches while competition prevails in interpatch spaces.We predicted that the NP would remain stable or decrease and PS would increase under GE treatment.To evaluate these predictions,we conducted a study in six lightly degraded alpine grasslands under free grazing(FG)conditions in Bangor County,Xizang Autonomous Region,China,with corresponding GE treatments using transects in 2017 and 2018.Results revealed that four sites in 2017 and five sites in 2018 had reduced NP and increased PS,with probabilities of 0.033(2017)and 0.004(2018),respectively,and a joint probability of 0.0001 under the null hypothesis that GE does not affect NP or PS.The NP reduction was solely due to the decrease in small patch sizes.An increase in PS was common across species,and a predominant tendency for NP reduction was observed among species across the sites.The overall changes in NP and PS were primarily driven by the three most abundant species(contributing more than 60%in both years),rather than by shifts in floristic composition.Our findings highlight that vegetation recovery in Bangor alpine steppes following GE relies solely on the expansion of existing patches rather than the recruitment of new ones in interpatch gaps.We recommend prioritizing growth-promoting measures,such as nutrient or water management,over seed addition when assisting with GE for restoring lightly degraded grasslands.展开更多
In this study,we developed a novel bilayered scaffold consisting of a bottom layer composed of the Decellularized Bovine Pericardium(DP)coated with Polyaniline Nanoparticles(PANINPs)and a top layer made of an electros...In this study,we developed a novel bilayered scaffold consisting of a bottom layer composed of the Decellularized Bovine Pericardium(DP)coated with Polyaniline Nanoparticles(PANINPs)and a top layer made of an electrospun Poly(lactic-co-glycolic acid)/Gelatin(PLGA/Gel)membrane incorporated with Vascular Endothelial Growth Fac-tor(VEGF)and hawthorn extract.Functionally,the DP supplies native Extracellular Matrix(ECM)components and mechanical support,while PANINPs provide conductivity.The electrospun PLGA/Gel layer mimics fibrous ECM.It incorporates bioactives,with VEGF promoting pro-angiogenic stimulation and hawthorn extract enhanc-ing anticoagulant activity,as well as increasing surface hydrophilicity.The tissue adhesive ensures the interfacial integrity between the two layers.Decellularization efficiency was confirmed histologically using 4',6-diamidino-2-phenylindole(DAPI)and Hematoxylin-Eosin(H&E)staining.The DP exhibited a DNA content of 115.9±47.8 ng/mg DNA,compared to 982.88±395.42 ng/mg in Native Pericardium(NP).The PANINPs had an average par-ticle size of 104.94±13.7 nm.The conductivity of PANINPs-coated decellularized pericardium was measured to be 9.093±8.6×10-4 S/cm using the four-point probe method.PLGA/Gel membranes containing hawthorn extract(1%,5%,10%,and 15%w/v)and VEGF(0.1μg/mL,0.5μg/mL,and 1μg/mL)were fabricated by electrospinning,result-ing in fiber diameters between 850 and 1200 nm and pore sizes between 14 and 20μm.The anticoagulant efficiency of the membranes containing hawthorn extract reached 430 s in the Activated Partial Thromboplastin Time Assay(aPTT).Mechanical testing revealed a tensile strength of 22.70±6.33 MPa,an elongation of 53.58±10.63%,and Young's modulus of 0.67±0.10 MPa.The scaffold also exhibited over 91%cell viability and excellent cardiomyo-cyte adhesion.The hemolysis ratio was determined to be 0.421±0.191%,which confirms its blood compatibility.Our results indicate that the proposed bilayered scaffold can be a promising candidate for cardiac patch applications.展开更多
AIM:To evaluate nanosilver eye patches versus Atrauman nanosilver dressings for ocular surface trauma.METHODS:This randomized non-inferiority trial(November 2024-April 2025)enrolled 60 patients assessed pre-treatment ...AIM:To evaluate nanosilver eye patches versus Atrauman nanosilver dressings for ocular surface trauma.METHODS:This randomized non-inferiority trial(November 2024-April 2025)enrolled 60 patients assessed pre-treatment and on days 1,7,and 14 post-treatment.The patients were then randomized into treatment(nanosilver eye patches)and control groups(Atrauman nanosilver dressings).Outcomes included wound healing,comfort(Ocular Comfort Index,OCI),and safety.Statistical analyses used t-tests,non-inferiority tests,and Chi-square tests.RESULTS:Patient baseline characteristics were comparable between groups,with a mean age of 60.633±10.934 in the treatment group versus 64.933±9.606 in controls,and similar gender distribution(20/10 vs 17/13 male/female).Both groups showed comparable baseline OCI scores(treatment group:6.100±2.187 vs control group:6.267±2.303,P=0.775).Following treatment,scores increased significantly at day 1(treatment group:9.367±2.251;control group:9.067±2.212,both P<0.001 vs baseline).Marked improvement was observed by day 7(treatment group:4.067±1.929;control group:3.900±1.918,P<0.001 vs baseline),with complete resolution at day 14(0.467±0.860 vs 0.467±1.008,P<0.001).The non-inferiority criterion was met.The treatment group showed greater improvement in Grade A wound healing rates(76.67%to 93.33%)compared to controls(80.00%to 86.67%)between 1 and 7d post-treatment.By 14d posttreatment,all patients achieved Grade A healing in both groups,with no Grade C cases observed throughout the study period.No adverse events were reported.CONCLUSION:Nanosilver eye patches are non-inferior to Atrauman dressings,offering effective,safe emergency care for ocular trauma.展开更多
The T-joints of Ti?6Al?4V alloy were manufactured by double-sided synchronized laser beam welding with the homologous filler wire. The formation, microstructure and mechanical properties of welded joints as well as th...The T-joints of Ti?6Al?4V alloy were manufactured by double-sided synchronized laser beam welding with the homologous filler wire. The formation, microstructure and mechanical properties of welded joints as well as the correlations of each other were investigated. The results indicate that the quality of weld seams is good without defects such as discontinuity, beading, visible cracks or porosity, which is linked to the steady molten pool behavior and droplet transition. The morphologies of the heat affected zone (HAZ) located on the skin and stringer are disparate. The microstructure of the HAZ and fusion zone (FZ) is mainly comprised of acicular martensiticα′ phases. The microhardness of the HAZ and FZ is higher than that of the base metal (BM) and reaches a maximum value at the HAZ near FZ on the stringer. The tensile specimens along the skin and stringer fractured at the BM with ductile fracture surfaces.展开更多
A double-sided silicon strip detector(DSSD)with active area of 48 mm x 48 mm and thickness of300μm has been developed. Each side of DSSD consists of48 strips, each with width of 0.9 mm and inter-strip separation of 0...A double-sided silicon strip detector(DSSD)with active area of 48 mm x 48 mm and thickness of300μm has been developed. Each side of DSSD consists of48 strips, each with width of 0.9 mm and inter-strip separation of 0.1 mm. Electrical properties and detection performances including full depletion bias voltage, reverse leakage current, rise time, energy resolution and cross talk have been studied. At a bias of 80 V, leakage current in each strip is less than 15 nA, and rise time for alpha particle at 5157 keV is approximately 15 ns on both sides.Good energy resolutions have been achieved with0.65-0.80% for the junction strips and 0.85-1.00% for the ohmic strips. The cross talk is found to be negligible on both sides. The overall good performance of DSSD indicates its readiness for various nuclear physics experiments.展开更多
AIM:To compare the efficacies of patching and penalization therapies for the treatment of amblyopia patients.METHODS:The records of 64 eyes of 50 patients 7 to16y of age who had presented to our clinics with a diagnos...AIM:To compare the efficacies of patching and penalization therapies for the treatment of amblyopia patients.METHODS:The records of 64 eyes of 50 patients 7 to16y of age who had presented to our clinics with a diagnosis of amblyopia,were evaluated retrospectively.Forty eyes of 26 patients who had received patching therapy and 24 eyes of 24 patients who had received penalization therapy included in this study.The latencies and amplitudes of visual evoked potential(VEP)records and best corrected visual acuities(BCVA)of these two groups were compared before and six months after the treatment.RESULTS:In both patching and the penalization groups,the visual acuities increased significantly following the treatments(P【0.05).The latency measurements of the P100 wave obtained at 1.0°,15 arc min.Patterns of both groups significantly decreased following the 6-months-treatment.However,the amplitude measurements increased(P【0.05).CONCLUSION:The patching and the penalization methods,which are the main methods used in the treatment of amblyopia,were also effective over the age of 7y,which has been accepted as the critical age for the treatment of amblyopia.展开更多
Sheets of aluminum 6061 alloy were welded using bypass-current double-sided arc welding with Al-Si filler wire to investigate the effect of Al-Si intermetallic compounds on the microstructure, microhardness and corros...Sheets of aluminum 6061 alloy were welded using bypass-current double-sided arc welding with Al-Si filler wire to investigate the effect of Al-Si intermetallic compounds on the microstructure, microhardness and corrosion behavior of weld joint. Experimental results indicated that the Al4.5FeSi phase in the topside of the weld joint was finer than that in the backside and newly formed phase of Al0.5Fe3Si0.5 was observed in the backside. The formation of reinforcing phases of Al-Fe-Si in the weld improved the microhardness of the weld by about 18%. The corrosion resistance of the weld zone was greater than that of the base metal, while the corrosion current displayed opposite, and the corrosion resistance of the weld region was better than that of the base metal.展开更多
The double-sided incremental forming(DSIF)improved the process flexibility compared to other incremental sheet forming(ISF)processes.Despite the flexible nature,it faces the challenge of low geometric precision like I...The double-sided incremental forming(DSIF)improved the process flexibility compared to other incremental sheet forming(ISF)processes.Despite the flexible nature,it faces the challenge of low geometric precision like ISF variants.In this work,two strategies are used to overcome this.First,a novel method is employed to determine the optimal support tool location for improving geometric precision.In this method,the toolpath oriented the tools to each other systematically in the circumferential direction.Besides,it squeezed the sheet by the same amount at the point of interest.The impacts of various support tool positions in the circumferential direction are evaluated for geometric precision.The results demonstrate that the support tool should support the master tool within 10°to its local normal in the circumferential direction to improve the geometric accuracy.Second,a two-stage process reduced the geometric error of the part by incrementally accommodating the springback error by artificially increasing the step size for the second stage.With the optimal support tool position and two-stage DSIF,the geometric precision of the part has improved significantly.The proposed method is compared to the best DSIF toolpath strategies for geometric accuracy,surface roughness,forming time,and sheet thickness fluctuations using grey relational analysis(GRA).It outperforms the other toolpath strategies including single-stage DSIF,accumulative double-sided incremental forming(ADSIF),and two-stage mixed double sided incre-mental forming(MDSIF).Our approach can improve geometric precision in complex parts by successfully employing the support tool and managing the springback incrementally.展开更多
In the double-sided arc welding system (DSAW) composing of PAW+TIG arcs, the PAW arc is guided by the TIG arc so that the current mostly flows through the direction of the workpiece thickness and the penetration is gr...In the double-sided arc welding system (DSAW) composing of PAW+TIG arcs, the PAW arc is guided by the TIG arc so that the current mostly flows through the direction of the workpiece thickness and the penetration is greatly improved. To analyze the current density distribution in DSAW is beneficial to understanding of this process. Considering all kinds of dynamic factors acting on the weldpool, this paper discusses firstly the surface deformation of the weldpool and the keyhole formation in PAW+TIG DSAW process on the basis of the magnetohydrodynamic theory and variation principles. Hence, a model of the current density distribution is developed. Through numerical simulation, the current density distribution in PAW+TIG DSAW process is quantitatively analyzed. It shows that the minimal radius of keyhole formed in PAW+TIG DSAW process is 0.5 mm and 89.5 percent of current flows through the keyhole.展开更多
In the proposed method, the current/arc is guided through the keyhole so that the energy of the plasma jet is compensated while it is consumed in heating the workpiece along the keyhole. As a result, deep narrow penet...In the proposed method, the current/arc is guided through the keyhole so that the energy of the plasma jet is compensated while it is consumed in heating the workpiece along the keyhole. As a result, deep narrow penetration has been achieved on 12.7 mm (1/2') thick stainless steel plates using 70 A welding current.展开更多
Friction stir welding (FSW) of aluminum alloys is currently utilized in several modern industries. The joints must have sufficient elastic?plastic response and formability levels similar to that of the base metal. In ...Friction stir welding (FSW) of aluminum alloys is currently utilized in several modern industries. The joints must have sufficient elastic?plastic response and formability levels similar to that of the base metal. In this work, double-sided FSW of AA6061 sheet was compared with its conventional single-sided one. An adjustable tool with different pin lengths (50%?95% of the sheet thickness) was used to perform the double-sided welds. Macro- and micro-structures, strength, and hardness of the joints were investigated to determine the optimum pin penetration depth. The best results were obtained for a double-sided joint made by a pin length equal to 65% of the sheet thickness, which showed an increase of 41% in the ultimate tensile strength compared with the single-sided joint.展开更多
文摘高压电缆长期过热可能导致绝缘热击穿,进而影响电网的稳定性。然而,当前研究主要集中在传统预测模型上,忽略了温度数据的复杂性和动态特征。为了解决此问题,提出一种基于多尺度Patch与卷积交互的电缆温度预测模型(MSP-CI)。首先,采用通道重组采样方法降低输入维度,并构建多尺度Patch分支结构,以实现复杂时间序列的解耦;其次,结合序列分解与卷积交互策略,分别提取粗粒度Patch的宏观信息与细粒度Patch的微观信息;最后,构建注意力融合模块,以动态平衡宏观与微观信息的权重,并得到最终的预测结果。在真实高压电缆温度数据集上的实验结果表明,MSP-CI相较于TimeMixer、PatchTST(Patch Time Series Transformer)和MSGNet(Multi-Scale interseries Graph Network)等基线模型,在均方误差(MSE)上下降了7.02%~34.87%,在平均绝对误差(MAE)上下降了5.15%~32.04%。可见,MSP-CI能有效提升电缆温度预测的准确率,为电力调度运行提供依据。
文摘光伏功率日前预测的准确性对电网的能源管理至关重要。针对光伏功率随机性及波动性大、预测精度不高的问题,文章提出一种基于PatchTST-STL模型的光伏发电功率日前预测方法。该方法通过引入时序块和季节趋势分解(seasonal and trend decomposition using loess,STL)改进Transformer的输入和架构,将每个时间步作为1个令牌(Token)改进为每个时序块(Patch)作为1个令牌,使得局部依赖关系被保留在1个令牌内,以提升局部模式捕捉能力,同时利用Transformer多头自注意力机制抽取序列长期依赖关系。考虑到光伏序列的模式复杂,采用STL对多变量光伏序列进行处理,分离出趋势、周期和残差部分,作为独立通道输入。使用灰狼优化算法(grey wolf optimizer,GWO)对模型超参数中时序块大小进行优化,以实现算法快速收敛。在澳大利亚沙漠知识太阳能中心数据集的实验结果表明,所提算法与Informer相比,平均绝对误差(mean absolute error,MAE)和均方根误差(root mean square error,RMSE)平均分别降低了36.7%和11.7%;与Transformer相比,MAE和RMSE平均分别降低了57.6%和30.9%。
基金supported by National Research Foundation of Korea(NRF)grants funded by the Korean government(MSIT)(No.RS-2023-00256265,RS-2024-00352352,RS-2024-00405818)the Korean Fund for Regenerative Medicine(KFRM)grant funded by the Korea government(the Ministry of Science and ICT,the Ministry of Health&Welfare).(No.25A0102L1)support from the Market-led K-sensor technology program(RS-2022-00154781,Development of large-area wafer-level flexible/stretchable hybrid sensor platform technology for form factor-free highly integrated convergence sensor),funded By the Ministry of Trade,Industry&Energy(MOTIE,Korea).
文摘Microneedles(MNs)have been extensively investigated for transdermal delivery of large-sized drugs,including proteins,nucleic acids,and even extracellular vesicles(EVs).However,for their sufficient skin penetration,conventional MNs employ long needles(≥600μm),leading to pain and skin irritation.Moreover,it is critical to stably apply MNs against complex skin surfaces for uniform nanoscale drug delivery.Herein,a dually amplified transdermal patch(MN@EV/SC)is developed as the stem cell-derived EV delivery platform by hierarchically integrating an octopusinspired suction cup(SC)with short MNs(≤300μm).While leveraging the suction effect to induce nanoscale deformation of the stratum corneum,MN@EV/SC minimizes skin damage and enhances the adhesion of MNs,allowing EV to penetrate deeper into the dermis.When MNs of various lengths are applied to mouse skin,the short MNs can elicit comparable corticosterone release to chemical adhesives,whereas long MNs induce a prompt stress response.MN@EV/SC can achieve a remarkable penetration depth(290μm)for EV,compared to that of MN alone(111μm).Consequently,MN@EV/SC facilitates the revitalization of fibroblasts and enhances collagen synthesis in middle-aged mice.Overall,MN@EV/SC exhibits the potential for skin regeneration by modulating the dermal microenvironment and ensuring patient comfort.
基金Supported by the Liaoning Provincial Natural Science Foundation(Grant No.2023-MSBA-008)Unveiling and Commanding Program of Liaoning Province(Grant No.2022JH1/10800080)the Fundamental Research Funds for the Central Universities(Grant No.DUT24MS008).
文摘The double-sided lapping process is extensively employed in the manufacturing of wafers,optical windows,and seal rings due to its high efficiency and ability to achieve precise flatness.However,limited research has explored the thickness uniformity among different workpieces after double-sided lapping,and the underlying mechanism remains unclear.To address the demand for higher precision,this paper first analyzed the relative kinematic model between the workpiece and the lapping plate to clarify the causes of thickness variations among workpieces after double-sided lapping.Subsequently,a finite element method(FEM)model was developed to account for the pressure distribution on the workpiece surfaces at the initial stage of the process.The results indicate that the number of workpieces influences the final thickness variation.Then,various sets of thin copper plates with different thicknesses were lapped,and the findings revealed that five copper plates processed simultaneously exhibited more uniform thickness compared to the three plates.The experimental results align well with the theoretical analysis.Ultimately,a thickness variation of less than 6μm was achieved on five copper plates measuringΦ100×2.9 mm.This study presents a comprehensive analysis of the mechanisms influencing thickness uniformity in the double-sided lapping process and provides practical guidelines for optimizing the process to achieve stringent precision standards in industrial applications.
基金financially supported by the National Key Research and Development Program(No.2023YFB4006100)the National Natural Science Foundation of China(No.52271232)+3 种基金Ningbo Youth Science and Technology Leading Talents Project(No.2023QL026)the Youth Innovation Promotion Association,CAS(No.2020300)the Natural Science Foundation of Zhejiang Province(Nos.LY21E020008 and LD21E020001)the“From 0 to 1”Innovative Program of CAS(No.ZDBS-LY-JSC021)
文摘Using abundant saline water for electrolysis,rather than limited freshwater,presents a promising technique for generating clean hydrogen energy.However,high concentration of corrosive chloride ions in saline water poses a great challenge in the stability of anode.In this study,we present a straightforward strategy to protect the anode from corrosion by patching the catalyst layer through a treatment of the anode with a sodium sulfide(Na2S) solution followed by electrochemical activation.The rapid sulfurization of the Ni electrode in Na2S results in the formation of a Na2S layer,which can subsequently be converted to NiOOH upon electrochemical activation,thereby shielding the inner Ni electrode from corrosion.The as-prepared electrode (P-NiFe-LDH/Ni) based on the strategy demonstrated stability over 3,500 h at an industrial current density of 0.5 A cm^(-2)in a 0.5 M NaCl and 1 M KOH solution.This study presents an effective strategy to significantly enhance the stability of anodes for saline water electrolysis by effectively patching the cracks in the catalyst layer.
基金financial support from the National Key Research and Development Program of China(2021YFC2400703)Zhengzhou City Major Special Project for Collaborative InnovationChina Scholarship Council。
文摘Bio-magnesium(Mg)alloys exhibit excellent biocompatibility and biodegradability,making them highly promising for implant applications.However,their limited strength-ductility balance remains a critical challenge restricting widespread use.In this study,ultra-fine-grained and homogeneous Mg alloys were fabricated using double-sided friction stir processing(DS-FSP)with liquid CO_(2) rapid cooling,leading to a significant enhancement in the strength-ductility synergy of the stirred zone.The results demonstrate that DS-FSP samples exhibit simultaneous improvements in ultimate tensile strength(UTS)and elongation,reaching 334.1±15 MPa and 28.2±7.3%,respectively.Compared to the non-uniform fine-grained microstructure obtained through single-sided friction stir processing,DS-FSP generates a uniform ultra-fine-grained structure,fundamentally altering the fracture behavior and mechanisms of Mg alloys.The DS-FSP samples exhibit irregular fracture patterns due to variations in basal slip system activation among different grains.In contrast,single-sided friction stir processing samples,characterized by a fine-grained yet heterogeneous microstructure,display flat shear fractures dominated by high-density dislocation initiation induced by twin formation,with fracture propagation dictated by the non-uniform texture.By achieving an ultra-fine grain size and homogeneous texture,DS-FSP effectively modifies the fracture mechanisms,thereby enhancing the strength-ductility balance of bio-magnesium alloys.
文摘Objective:To evaluate the intervention effect of childlike nursing combined with Chinese herbal patching on pediatric bronchopneumonia.Methods:1036 children with bronchopneumonia(one family member included for each child)who were admitted to the hospital between January 2024 and June 2024 were selected and randomly divided into two groups using a random number table.The combined group received childlike nursing combined with Chinese herbal patching,while the control group received routine nursing.Symptom recovery time,treatment compliance,inflammatory factor levels,quality of life of the children,and family satisfaction were compared between the two groups.Results:The symptom recovery time in the combined group was shorter than that in the control group,treatment compliance was higher,inflammatory factor levels after intervention were lower,quality of life scores of the children were lower,and family satisfaction was higher(P<0.05).Conclusion:The implementation of childlike nursing combined with Chinese herbal patching for children with bronchopneumonia can shorten their symptom recovery time,significantly improve treatment compliance and quality of life,reduce inflammatory reactions,and achieve high satisfaction among family members.
基金financially supported by the Science and Technology Bureau of Ali Prefecture,project named“Assessing the Carbon Sequestration and Carbon Sink Enhancement Potential of Natural Ecosystems in Ali Region(QYXTZX-AL2022-05)”。
文摘The alpine grassland vegetation on the Qinghai-Tibet Plateau is composed of plant patches in varied sizes.It remains uncertain whether vegetation recovery following grazing exclusion(GE)in degraded grasslands is driven by increases in patches number(NP),patch size(PS),or both.We based our predictions on two hypotheses:GE intensifies plant competition,and facilitation prevails near patches while competition prevails in interpatch spaces.We predicted that the NP would remain stable or decrease and PS would increase under GE treatment.To evaluate these predictions,we conducted a study in six lightly degraded alpine grasslands under free grazing(FG)conditions in Bangor County,Xizang Autonomous Region,China,with corresponding GE treatments using transects in 2017 and 2018.Results revealed that four sites in 2017 and five sites in 2018 had reduced NP and increased PS,with probabilities of 0.033(2017)and 0.004(2018),respectively,and a joint probability of 0.0001 under the null hypothesis that GE does not affect NP or PS.The NP reduction was solely due to the decrease in small patch sizes.An increase in PS was common across species,and a predominant tendency for NP reduction was observed among species across the sites.The overall changes in NP and PS were primarily driven by the three most abundant species(contributing more than 60%in both years),rather than by shifts in floristic composition.Our findings highlight that vegetation recovery in Bangor alpine steppes following GE relies solely on the expansion of existing patches rather than the recruitment of new ones in interpatch gaps.We recommend prioritizing growth-promoting measures,such as nutrient or water management,over seed addition when assisting with GE for restoring lightly degraded grasslands.
文摘In this study,we developed a novel bilayered scaffold consisting of a bottom layer composed of the Decellularized Bovine Pericardium(DP)coated with Polyaniline Nanoparticles(PANINPs)and a top layer made of an electrospun Poly(lactic-co-glycolic acid)/Gelatin(PLGA/Gel)membrane incorporated with Vascular Endothelial Growth Fac-tor(VEGF)and hawthorn extract.Functionally,the DP supplies native Extracellular Matrix(ECM)components and mechanical support,while PANINPs provide conductivity.The electrospun PLGA/Gel layer mimics fibrous ECM.It incorporates bioactives,with VEGF promoting pro-angiogenic stimulation and hawthorn extract enhanc-ing anticoagulant activity,as well as increasing surface hydrophilicity.The tissue adhesive ensures the interfacial integrity between the two layers.Decellularization efficiency was confirmed histologically using 4',6-diamidino-2-phenylindole(DAPI)and Hematoxylin-Eosin(H&E)staining.The DP exhibited a DNA content of 115.9±47.8 ng/mg DNA,compared to 982.88±395.42 ng/mg in Native Pericardium(NP).The PANINPs had an average par-ticle size of 104.94±13.7 nm.The conductivity of PANINPs-coated decellularized pericardium was measured to be 9.093±8.6×10-4 S/cm using the four-point probe method.PLGA/Gel membranes containing hawthorn extract(1%,5%,10%,and 15%w/v)and VEGF(0.1μg/mL,0.5μg/mL,and 1μg/mL)were fabricated by electrospinning,result-ing in fiber diameters between 850 and 1200 nm and pore sizes between 14 and 20μm.The anticoagulant efficiency of the membranes containing hawthorn extract reached 430 s in the Activated Partial Thromboplastin Time Assay(aPTT).Mechanical testing revealed a tensile strength of 22.70±6.33 MPa,an elongation of 53.58±10.63%,and Young's modulus of 0.67±0.10 MPa.The scaffold also exhibited over 91%cell viability and excellent cardiomyo-cyte adhesion.The hemolysis ratio was determined to be 0.421±0.191%,which confirms its blood compatibility.Our results indicate that the proposed bilayered scaffold can be a promising candidate for cardiac patch applications.
基金Supported by High and New Technology Project of Hainan Key Research and Development Plan(No.ZDYF2024GXJS032)Health Care Special Project of PLA Logistics Research Fund(No.23BJZ37)Scientific Research Project of Health Industry in Hainan Province(No.22A200351).
文摘AIM:To evaluate nanosilver eye patches versus Atrauman nanosilver dressings for ocular surface trauma.METHODS:This randomized non-inferiority trial(November 2024-April 2025)enrolled 60 patients assessed pre-treatment and on days 1,7,and 14 post-treatment.The patients were then randomized into treatment(nanosilver eye patches)and control groups(Atrauman nanosilver dressings).Outcomes included wound healing,comfort(Ocular Comfort Index,OCI),and safety.Statistical analyses used t-tests,non-inferiority tests,and Chi-square tests.RESULTS:Patient baseline characteristics were comparable between groups,with a mean age of 60.633±10.934 in the treatment group versus 64.933±9.606 in controls,and similar gender distribution(20/10 vs 17/13 male/female).Both groups showed comparable baseline OCI scores(treatment group:6.100±2.187 vs control group:6.267±2.303,P=0.775).Following treatment,scores increased significantly at day 1(treatment group:9.367±2.251;control group:9.067±2.212,both P<0.001 vs baseline).Marked improvement was observed by day 7(treatment group:4.067±1.929;control group:3.900±1.918,P<0.001 vs baseline),with complete resolution at day 14(0.467±0.860 vs 0.467±1.008,P<0.001).The non-inferiority criterion was met.The treatment group showed greater improvement in Grade A wound healing rates(76.67%to 93.33%)compared to controls(80.00%to 86.67%)between 1 and 7d post-treatment.By 14d posttreatment,all patients achieved Grade A healing in both groups,with no Grade C cases observed throughout the study period.No adverse events were reported.CONCLUSION:Nanosilver eye patches are non-inferior to Atrauman dressings,offering effective,safe emergency care for ocular trauma.
基金Project supported by Science and Technology on Power Beam Processes Laboratory at Beijing Aeronautical Manufacturing Technology Research Institute,China
文摘The T-joints of Ti?6Al?4V alloy were manufactured by double-sided synchronized laser beam welding with the homologous filler wire. The formation, microstructure and mechanical properties of welded joints as well as the correlations of each other were investigated. The results indicate that the quality of weld seams is good without defects such as discontinuity, beading, visible cracks or porosity, which is linked to the steady molten pool behavior and droplet transition. The morphologies of the heat affected zone (HAZ) located on the skin and stringer are disparate. The microstructure of the HAZ and fusion zone (FZ) is mainly comprised of acicular martensiticα′ phases. The microhardness of the HAZ and FZ is higher than that of the base metal (BM) and reaches a maximum value at the HAZ near FZ on the stringer. The tensile specimens along the skin and stringer fractured at the BM with ductile fracture surfaces.
基金supported by the National Natural Science Foundation of China(Nos.U1432246,U1632136,U1432127,11375268,11635015,and 11475263)the National Basic Research Program of China(No.2013CB834404)
文摘A double-sided silicon strip detector(DSSD)with active area of 48 mm x 48 mm and thickness of300μm has been developed. Each side of DSSD consists of48 strips, each with width of 0.9 mm and inter-strip separation of 0.1 mm. Electrical properties and detection performances including full depletion bias voltage, reverse leakage current, rise time, energy resolution and cross talk have been studied. At a bias of 80 V, leakage current in each strip is less than 15 nA, and rise time for alpha particle at 5157 keV is approximately 15 ns on both sides.Good energy resolutions have been achieved with0.65-0.80% for the junction strips and 0.85-1.00% for the ohmic strips. The cross talk is found to be negligible on both sides. The overall good performance of DSSD indicates its readiness for various nuclear physics experiments.
文摘AIM:To compare the efficacies of patching and penalization therapies for the treatment of amblyopia patients.METHODS:The records of 64 eyes of 50 patients 7 to16y of age who had presented to our clinics with a diagnosis of amblyopia,were evaluated retrospectively.Forty eyes of 26 patients who had received patching therapy and 24 eyes of 24 patients who had received penalization therapy included in this study.The latencies and amplitudes of visual evoked potential(VEP)records and best corrected visual acuities(BCVA)of these two groups were compared before and six months after the treatment.RESULTS:In both patching and the penalization groups,the visual acuities increased significantly following the treatments(P【0.05).The latency measurements of the P100 wave obtained at 1.0°,15 arc min.Patterns of both groups significantly decreased following the 6-months-treatment.However,the amplitude measurements increased(P【0.05).CONCLUSION:The patching and the penalization methods,which are the main methods used in the treatment of amblyopia,were also effective over the age of 7y,which has been accepted as the critical age for the treatment of amblyopia.
基金financially supported by the National Natural Science Foundation of China(No.51005049)
文摘Sheets of aluminum 6061 alloy were welded using bypass-current double-sided arc welding with Al-Si filler wire to investigate the effect of Al-Si intermetallic compounds on the microstructure, microhardness and corrosion behavior of weld joint. Experimental results indicated that the Al4.5FeSi phase in the topside of the weld joint was finer than that in the backside and newly formed phase of Al0.5Fe3Si0.5 was observed in the backside. The formation of reinforcing phases of Al-Fe-Si in the weld improved the microhardness of the weld by about 18%. The corrosion resistance of the weld zone was greater than that of the base metal, while the corrosion current displayed opposite, and the corrosion resistance of the weld region was better than that of the base metal.
基金supported by the National Natural Science Foun-dation of China(Nos.52075025,51975328)Project funded by China Postdoctoral Science Foundation(No.2021T140418)。
文摘The double-sided incremental forming(DSIF)improved the process flexibility compared to other incremental sheet forming(ISF)processes.Despite the flexible nature,it faces the challenge of low geometric precision like ISF variants.In this work,two strategies are used to overcome this.First,a novel method is employed to determine the optimal support tool location for improving geometric precision.In this method,the toolpath oriented the tools to each other systematically in the circumferential direction.Besides,it squeezed the sheet by the same amount at the point of interest.The impacts of various support tool positions in the circumferential direction are evaluated for geometric precision.The results demonstrate that the support tool should support the master tool within 10°to its local normal in the circumferential direction to improve the geometric accuracy.Second,a two-stage process reduced the geometric error of the part by incrementally accommodating the springback error by artificially increasing the step size for the second stage.With the optimal support tool position and two-stage DSIF,the geometric precision of the part has improved significantly.The proposed method is compared to the best DSIF toolpath strategies for geometric accuracy,surface roughness,forming time,and sheet thickness fluctuations using grey relational analysis(GRA).It outperforms the other toolpath strategies including single-stage DSIF,accumulative double-sided incremental forming(ADSIF),and two-stage mixed double sided incre-mental forming(MDSIF).Our approach can improve geometric precision in complex parts by successfully employing the support tool and managing the springback incrementally.
基金The authors wish to express their gratitude to the financial support to this project from the project foundation of the National Key Laboratory of Advanced Welding Production Technology of Harbin Institute of Technology and the US National Science Foundation under grant No.DMI 9812981
文摘In the double-sided arc welding system (DSAW) composing of PAW+TIG arcs, the PAW arc is guided by the TIG arc so that the current mostly flows through the direction of the workpiece thickness and the penetration is greatly improved. To analyze the current density distribution in DSAW is beneficial to understanding of this process. Considering all kinds of dynamic factors acting on the weldpool, this paper discusses firstly the surface deformation of the weldpool and the keyhole formation in PAW+TIG DSAW process on the basis of the magnetohydrodynamic theory and variation principles. Hence, a model of the current density distribution is developed. Through numerical simulation, the current density distribution in PAW+TIG DSAW process is quantitatively analyzed. It shows that the minimal radius of keyhole formed in PAW+TIG DSAW process is 0.5 mm and 89.5 percent of current flows through the keyhole.
基金This work is supported by the National Natural Science Foundation under Grant DMI-9812981
文摘In the proposed method, the current/arc is guided through the keyhole so that the energy of the plasma jet is compensated while it is consumed in heating the workpiece along the keyhole. As a result, deep narrow penetration has been achieved on 12.7 mm (1/2') thick stainless steel plates using 70 A welding current.
基金The support of Iran National Science Foundation (INSF) (Grant No. 91051732)
文摘Friction stir welding (FSW) of aluminum alloys is currently utilized in several modern industries. The joints must have sufficient elastic?plastic response and formability levels similar to that of the base metal. In this work, double-sided FSW of AA6061 sheet was compared with its conventional single-sided one. An adjustable tool with different pin lengths (50%?95% of the sheet thickness) was used to perform the double-sided welds. Macro- and micro-structures, strength, and hardness of the joints were investigated to determine the optimum pin penetration depth. The best results were obtained for a double-sided joint made by a pin length equal to 65% of the sheet thickness, which showed an increase of 41% in the ultimate tensile strength compared with the single-sided joint.
