Three sets of MXene(Ti_(3)C_(2)T_(x))@nano-Fe_(1)Co_(0.8)Ni_(1)composites with 15,45,and 90 mg MXene were prepared by in-situ liquid-phase deposition to effectively investigate the impact of the relationship between M...Three sets of MXene(Ti_(3)C_(2)T_(x))@nano-Fe_(1)Co_(0.8)Ni_(1)composites with 15,45,and 90 mg MXene were prepared by in-situ liquid-phase deposition to effectively investigate the impact of the relationship between MXene(Ti_(3)C_(2)T_(x))and nano-Fe_(1)Co_(0.8)Ni_(1)magnetic particles on the electromagnetic absorption properties of the composites.The microstructure,static magnetic properties,and electromag-netic absorption performance of these composites were studied.Results indicate that the MXene@nano-Fe_(1)Co_(0.8)Ni_(1)composites were primarily composed of face-centered cubic crystal structure particles and MXene,with spherical Fe_(1)Co_(0.8)Ni_(1)particles uniformly distrib-uted on the surface of the multilayered MXene.The alloy particles had an average particle size of approximately 100 nm and exhibited good dispersion without noticeable particle aggregation.With the increase in MXene content,the specific saturation magnetic and coer-civity of the composite initially decreased and then increased,displaying typical soft magnetic properties.Compared with those of the Fe_(1)Co_(0.8)Ni_(1)magnetic alloy particles alone,MXene addition caused an increasing trend in the real and imaginary parts of the dielectric constant of the composite.Meanwhile,the real and imaginary parts of the magnetic permeability exhibit decreasing trend.With the in-crease in MXene addition,the material attenuation constant increased and the impedance matching decreased.The minimum reflection loss increased,and the maximum effective absorption bandwidth decreased.When the MXene addition was 90 mg,the composite exhib-ited a minimum reflection loss of-46.9 dB with a sample thickness of 1.1 mm and a maximum effective absorption bandwidth of 3.60 GHz with a sample thickness of 1.0 mm.The effective absorption bandwidth of the composites and their corresponding thicknesses showed a decreasing trend with the increase in MXene addition,reducing by 50%from 1.5 mm without MXene addition to 1 mm with 90 mg of MXene addition.展开更多
Intractable delays occur in air traffic due to the imbalance between ever-increasing air traffic demand and limited airspace capacity.As air traffic is associated with complex air transport systems,delays can be magni...Intractable delays occur in air traffic due to the imbalance between ever-increasing air traffic demand and limited airspace capacity.As air traffic is associated with complex air transport systems,delays can be magnified and propagated throughout these systems,resulting in the emergent behavior known as delay propagation.An understanding of delay propagation dynamics is pertinent to modern air traffic management.In this work,we present a complex network perspective of delay propagation dynamics.Specifically,we model air traffic scenarios using spatial–temporal networks with airports as the nodes.To establish the dynamic edges between the nodes,we develop a delay propagation method and apply it to a given set of air traffic schedules.Based on the constructed spatial-temporal networks,we suggest three metrics-magnitude,severity,and speed-to gauge delay propagation dynamics.To validate the effectiveness of the proposed method,we carry out case studies on domestic flights in the Southeastern Asia region(SAR)and the United States.Experiments demonstrate that the propagation magnitude in terms of the number of flights affected by delay propagation and the amount of propagated delays for the US traffic are respectively five and ten times those of the SAR.Experiments further reveal that the propagation speed for US traffic is eight times faster than that of the SAR.The delay propagation dynamics reveal that about six hub airports in the SAR have significant propagated delays,while the situation in the United States is considerably worse,with a corresponding number of around 16.This work provides a potent tool for tracing the evolution of air traffic delays.展开更多
FeGa alloy is a new kind of magnetostrictive material, and rare-earth cerium can improve its magnetostrictive property.（Fe（81）Ga（19））（100-x）Cex（x = 0, 0.3 at%, 0.7 at%, 1 at%） samples were prepared by doping...FeGa alloy is a new kind of magnetostrictive material, and rare-earth cerium can improve its magnetostrictive property.（Fe（81）Ga（19））（100-x）Cex（x = 0, 0.3 at%, 0.7 at%, 1 at%） samples were prepared by doping cerium in Fe（81）Ga（19） alloy. Their microstructures and phases were studied, and valence electronic structures were investigated. Electromagnetic parameters, such as coercivity, saturation magnetization,remnant magnetization and saturation magnetostrictive coefficients（λs） of every sample were measured.Cerium atoms are distributed at grain boundaries, and the Ce-doped alloys remain the A2 structure of FeGa alloy. When x is 0.7, the value of saturation magnetism is 217.08 emu/g, which is the maximum in the Ce-doped samples. The equivalent half length of single bond is the maximum also, and reaches to0.11380 nm. At the same time, the number of covalent electrons is 3.5672, and is the minimum of the Cedoped samples. Its As is the largest in the four samples. The change of As results in the change of equivalent half length of single bond in Ce-doped alloy.展开更多
Gas-liquid two-phase flow widely exits in production and transportation of petroleum industry.Characterizing gas-liquid flow and measuring flow parameters represent challenges of great importance,which contribute to t...Gas-liquid two-phase flow widely exits in production and transportation of petroleum industry.Characterizing gas-liquid flow and measuring flow parameters represent challenges of great importance,which contribute to the recognition of flow regime and the optimal design of industrial equipment.In this paper,we propose a novel complex network-based deep learning method for characterizing gas-liquid flow.Firstly,we map the multichannel measurements to multiple limited penetrable visibility graphs(LPVGs)and obtain their degree sequences as the graph representation.Based on the degree distribution,we analyze the complicated flow behavior under different flow structures.Then,we design a dual-input convolutional neural network to fuse the raw signals and the graph representation of LPVGs for the classification of flow structures and measurement of gas void fraction.We implement the model with two parallel branches with the same structure,each corresponding to one input.Each branch consists of a channel-projection convolutional part,a spatial-temporal convolutional part,a dense block and an attention module.The outputs of the two branches are concatenated and fed into several full connected layers for the classification and measurement.At last,our method achieves an accuracy of 95.3%for the classification of flow structures,and a mean squared error of 0.0038 and a mean absolute percent error of 6.3%for the measurement of gas void fraction.Our method provides a promising solution for characterizing gas-liquid flow and measuring flow parameters.展开更多
In order to estimate vehicular queue length at signalized intersections accurately and overcome the shortcomings and restrictions of existing studies especially those based on shockwave theory,a new methodology is pre...In order to estimate vehicular queue length at signalized intersections accurately and overcome the shortcomings and restrictions of existing studies especially those based on shockwave theory,a new methodology is presented for estimating vehicular queue length using data from both point detectors and probe vehicles. The methodology applies the shockwave theory to model queue evolution over time and space. Using probe vehicle locations and times as well as point detector measured traffic states,analytical formulations for calculating the maximum and minimum( residual) queue length are developed. The proposed methodology is verified using ground truth data collected from numerical experiments conducted in Shanghai,China. It is found that the methodology has a mean absolute percentage error of 17. 09%,which is reasonably effective in estimating the queue length at traffic signalized intersections. Limitations of the proposed models and algorithms are also discussed in the paper.展开更多
With the advancement of Communication,Navigation and Surveillance(CNS)technolo-gies such as space-based Automatic Dependent Surveillance-Broadcast/Contract(ADS-B/C),large separation minima may be reduced in procedural...With the advancement of Communication,Navigation and Surveillance(CNS)technolo-gies such as space-based Automatic Dependent Surveillance-Broadcast/Contract(ADS-B/C),large separation minima may be reduced in procedural airspaces.It is of great significance to know the upper limit of the Reduced Separation Minima(RSM)for a procedural airspace and the corre-sponding consequences on collision risk with specifics of the advanced ADS-B and control interven-tion model.In this work,an interactive software is first developed for collision risk estimation.This software integrates the International Civil Aviation Organization(ICAO)collision risk models for lateral and longitudinal collision risk calculation for the Singapore procedural airspace.Results demonstrate that the lateral and longitudinal collision risk of Singapore procedural airspace with respect to current control procedures meets the ICAO Target Level of Safety(TLS)standard.Moreover,the feasibility of reducing the horizontal separations implemented in the Singapore pro-cedural airspace with respect to advanced CNS techniques is investigated.It is found that if advanced CNS technologies are applied,then the current 50-NM lateral and longitudinal separa-tion standards can be reduced to 22 NM(1 NM=1.825 km)and 20 NM,respectively,to meet the TLS standards based on current demand.A method is then devised to expand the traffic demand by p for p∈[10%,200%].It is found that the minimum lateral and longitudinal separa-tions can be reduced from 50 NM to be within the range of[23,31]NM,and 20 NM,respectively,for p∈[10%,200%],while the collision risk still meets the TLS standards.展开更多
Objective: To observe the clinical efficacy and safety of low dose tacrolimus (TAC) combined with tripterygium (TW) in treatment of steroid resistant nephritic syndrome (SRNS). Method: The patients, who were diagnosed...Objective: To observe the clinical efficacy and safety of low dose tacrolimus (TAC) combined with tripterygium (TW) in treatment of steroid resistant nephritic syndrome (SRNS). Method: The patients, who were diagnosed with mesangial proliferative glomerulonephritis (MesPGN) and focal segmental glomerulosclerosis (FSGS) by biopsy and failed to respond to a 3-month treatment with prednisone (1 mg/kg·d), were randomly divided into 2 groups (TAC + TW Group and TW Group). Initially TAC + TW group took TAC 0.05mg/(kg·d) 2 h after meal at 12 h interval. The plasma TAC level was examined after 3 days and was kept at 1.5 - 4 ng·ml;meanwhile, TW was given at 60 mg/d before meal. TW group only took TW (60 mg/d). The efficacy, adverse reactions and plasma TAC levels were observed in each group. Results: 1) Totally 20 SRNS patients completed the trial, 11 of TAC + TW Group and 9 of TW Group. There is no statistical difference between the two groups in terms of age, gender, duration since onset of the disease, blood pressure, 24 h UPQ, serum albumin, creatinine, cholesterol, triglyceride, FBG, kidney pathological categories, time of taking prednisone etc.;2) Urine protein started to decrease after 1 month treatment in both of TAC + TW and TW groups. By the 12th month of treatment, TAC + TW group showed 8 cases of complete remission (72.7%), 2 cases of partial remission (18.2%) and 1 case of no improvement (9.1%), while those of TW groups were 2 (22.2%), 4 (44.5%) and 3 (33.3%), respectively;3) With treatment, the TAC + TW Group patients’ plasma protein was significantly higher than that of pretreatment stage and recovered to normal level after 6 month of treatment. However, there was no significant plasma protein increase in TW Group. No obvious changes were observed on serum creatinine level of patients of both the two groups;4) The incidence of adverse reactions was not significantly different between the two groups. Conclusion: TAC + TW reduced proteinuria of SRNS patients, increased clinical remission rate and was tolerant to SRNS patients. We conclude that TAC + TW treatment is an effective way to treat patients with SRNS.展开更多
Recent studies have made substantial progress in understanding the interactions between cognitive functions, from language to cognitive control, attention, and memory. However, dissociating these functions has been ha...Recent studies have made substantial progress in understanding the interactions between cognitive functions, from language to cognitive control, attention, and memory. However, dissociating these functions has been hampered by the close proximity of regions involved, as in the case in the prefrontal and parietal cortex. In this article, we review a series of studies that investigated the relationship between language and other cognitive functions in an alternative way - by examining their functional （co-）lateralization. We argue that research on the hemispheric lateralization of language and its link with handedness can offer an appropriate starting- point to shed light on the relationships between different functions. Besides functional interactions, anatomical asymmetries in non-human primates and those underlying language in humans can provide unique information about cortical organization. Finally, some open questions and criteria are raised for an ideal theoretical model of the cortex based on hemispheric specialization.展开更多
BACKGROUND：Carotid intima media thickness （CIMT） and stiffness are taken as useful surrogate markers of atherosclerosis. In China, the number of elderly patients undergoing hemodialysis has increased year by year, ...BACKGROUND：Carotid intima media thickness （CIMT） and stiffness are taken as useful surrogate markers of atherosclerosis. In China, the number of elderly patients undergoing hemodialysis has increased year by year, with the increase of dialysis-related cardiovascular events. This study was undertaken to examine carotid stiffness in elderly hemodialysis patients by the ultrasound techniques in order to find out the possible risk factors. From January 2006 to February 2010, a total of 87 patients （41 males and 46 females） treated with routine hemodialysis at the 97th Hospital of People＇s Liberation Army were enrolled in this study. The distensibility coefficient （DC） of the carotid artery was detected by Doppler ultrasonic diagnosis apparatus （Philips HBI5000, frequency 12 MHz） for evaluation of arterial stiffness. Serum albumin, total cholesterol （TC）, high density lipoprotein （HDL）, low density lipoprotein （LDL）, triglyceride （TG）, glucose, creatinine, calcium, phosphorus, and intact parathyroid hormone （iPTH） were examined with standard methods. The liner correlation and multiple stepwise regression analysis were used to find correlations between them. RESULTS： In this study, the systolic blood pressure was 153.33±25.98 mmHg, DBP 84.22± 10.39 mmHg, TC 4.39±1.05 mmol/L, TG 1.36±0.72 mmol/L, LDL 2.47±0.77 mmol/L, Cr 889.82± 207.38 μmol/L, Glu 5.36±1.87 mmol/L, Ca 12.00±2.19±0.21 mmol/L, and DC 13.39±5.32×10-3/kPa. DC was associated with age （r =-0.459, P〈0.001）, SBP （r =-0.527, P〈0.001）, and serum calcium （r =-0.273, P=0.011）. The multiple stepwise regression analysis showed that SBP, age, increased serum calcium level, and diabetes were independent risk factors for decreasing DC. CONCLUSION： Systolic blood pressure, age, increased serum calcium level and diabetes in elderly hemodialysis patients are independent risk factors for increased carotid arterial stiffness.展开更多
The AlGaN/GaN p-n junction has received extensive attention due to its capability of rapid photogenerated carrier separation in photodetection devices.The AlGaN/GaN heterojunction nanowires(NWs)have been especially en...The AlGaN/GaN p-n junction has received extensive attention due to its capability of rapid photogenerated carrier separation in photodetection devices.The AlGaN/GaN heterojunction nanowires(NWs)have been especially endowed with new life for distinctive transport characteristics in the photoelectrochemical(PEC)detection field.A self-powered PEC ultraviolet photodetector(PEC UV PD)based on the p-AlGaN/n-GaN heterojunction NW is reported in this work.The n-GaN NW layer plays a crucial role as a current flow hub to regulate carrier transport,which mainly acts as a light absorber under 365 nm and carrier recombination layer under 255 nm illumination,which can effectively modulate photoresponsivity at different wavelengths.Furthermore,by designing the thicknesses of the NW layer,the photocurrent polarity reversal was successfully achieved in the constructed AlGaN/GaN NW PEC UV PD at two different light wavelengths.In addition,by combining with platinum decoration,the photoresponse performance could be further enhanced.Our work provides insight into transport mechanisms in the AlGaN/GaN NW PEC system,and offers a feasible and comprehensive strategy for further exploration of multifunctional optoelectronic devices.展开更多
We investigate the negative transconductance effect in p-GaN gate AlGaN/GaN high-electron-mobility transistor(HEMT) associated with traps in the unintentionally doped GaN buffer layer. We find that a negative transcon...We investigate the negative transconductance effect in p-GaN gate AlGaN/GaN high-electron-mobility transistor(HEMT) associated with traps in the unintentionally doped GaN buffer layer. We find that a negative transconductance effect occurs with increasing the trap concentration and capture cross section when calculating transfer characteristics.The electron tunneling through AlGaN barrier and the reduced electric field discrepancy between drain side and gate side induced by traps are reasonably explained by analyzing the band diagrams, output characteristics, and the electric field strength of the channel of the devices under different trap concentrations and capture cross sections.展开更多
To suppress the electric field crowding at sidewall and improve the detection sensitivity of the AlGaN separate absorption and multiplication(SAM)avalanche photodiodes(APDs),we propose the new AlGaN APDs structure com...To suppress the electric field crowding at sidewall and improve the detection sensitivity of the AlGaN separate absorption and multiplication(SAM)avalanche photodiodes(APDs),we propose the new AlGaN APDs structure combining a large-area mesa with a field plate(FP).The simulated results show that the proposed AlGaN APDs exhibit a significant increase in avalanche gain,about two orders of magnitude,compared to their counterparts without FP structure,which is attributed to the suppression of electric field crowding at sidewall of multiplication layer and the reduction of the maximum electric field at the p-type GaN sidewall in p-n depletion region.Meanwhile,the APDs can produce an obviously enhanced photocurrent due to the increase in cross sectional area of multiplication region.展开更多
Based on a comprehensive eco-geochemical survey of Shandong Province,the differences in pesticide residue situation and contents of DDTs and HCHs in the soils of Yantai City and Southwest Shandong Province(abbreviated...Based on a comprehensive eco-geochemical survey of Shandong Province,the differences in pesticide residue situation and contents of DDTs and HCHs in the soils of Yantai City and Southwest Shandong Province(abbreviated as SSP)were studied in this paper.The results showed that the detection rates of DDTs and HCHs in the soil of SSP were apparently higher than Yantai City.However,the mean contents of DDTs and HCHs in the soil of Yantai were 9 and 25 times of SSP,respectively,and higher than the mean contents of many other cities and areas.p,p′-DDE was the main pesticide residual form in the soil of SSP.It is recognized as the degradation product of DDTs in oxidation environment in past,nevertheless,5.52%of the soils in Yantai City still have a little of DDT input recently,which has posed a big impact on soil environment quality.β-HCH was the main form of the four isomers of HCHs in Yantai City,andα-HCH/γ-HCH in SSP was low.These reveal that the residual time of HCHs in the soils of both the two areas has a long period.After primary analysis,the risk of DDTs and HCHs in the soil of SSP is low,but DDTs in the soil of Yantai City still has a certain risk.展开更多
In 2007- 2008,a systematic survey,collection and arrangement was carried out for agricultural biological resources and traditional cultural knowledge of Hani People in 8 counties,15 towns,and 23 village committees of ...In 2007- 2008,a systematic survey,collection and arrangement was carried out for agricultural biological resources and traditional cultural knowledge of Hani People in 8 counties,15 towns,and 23 village committees of Yunnan Province. A total of 299 samples were obtained about agricultural biological resources related to production and living of Hani People. According to purpose of utilization,samples were divided into grain crops,medicinal plants,vegetables,fruit trees,and oil crops,taking up 48. 2%,21. 7%,18. 4%,7. 7%,and 2. 0% of the samples respectively. The survey indicated that planting industry and breeding industry take up the dominant role in rural social economy of Hani People,so agricultural biological resources are the fundamental means of production maintaining rural social development of Hani People.The current situation of agricultural biological resources of Hani People in Yunnan,reasons for growth and decline were analyzed,and the utilization,protection and development of agricultural biological resources were discussed.展开更多
The land quality geochemical evaluation database was mainly based on soil geochemical surveys.During its construction process,geochemical survey data involving atmospheric dry(wet)sediments,irrigation water,fertilizer...The land quality geochemical evaluation database was mainly based on soil geochemical surveys.During its construction process,geochemical survey data involving atmospheric dry(wet)sediments,irrigation water,fertilizers and crops was simultaneously collected,analyzed and compiled into result maps using MAPGIS.ACCESS was used to manage standardized result data to establish an evaluation database.The database included a basic spatial database involving regional geography,topography,soil type and land use,a spatial evaluation database centered on the sampling layout of the work areas of soil,irrigation water,crops and other media,the distribution and changes of soil chemical elements,the classification of soil pollution and the classification of soil element environment and nutrients,and an evaluation database of various result maps such as land planning map,characteristic agricultural product planting plan suggestion map and fertilization suggestion map.The database realized the scientific and effective management of the samples and corresponding numerous laboratory analysis data,and provides basic information for the geochemical survey and evaluation of the land quality in the evaluation areas and the overall comprehensive research,and an important basis for promoting the adjustment of agricultural economic planning,the development of modern green agriculture and the development and utilization of high-quality characteristic land resources.展开更多
Objective：To record Calcium, Potassium and Sodium currents in acutely isolated hippocampal pyramidal neurons. Methods：Hippocampal CA3 neurons were freshly isolated by 1 mg protease/3 ml SES and mechanical trituratio...Objective：To record Calcium, Potassium and Sodium currents in acutely isolated hippocampal pyramidal neurons. Methods：Hippocampal CA3 neurons were freshly isolated by 1 mg protease/3 ml SES and mechanical trituration with polished pipettes of progressively smaller tip diameters. Patch clamp technique in whole-cell mode was employed to record voltage-gated channel currents. Results：The procedure dissociated hippocampal neurons, preserving apical dendrites and several basal dendrites, without impairing the electrical characteristics of the neurons. Whole-cell patch clamp configuration was successfully used to record voltage-gated Ca^2＋ currents, delayed rectifier K^＋ current and voltage-gated Na^＋ currents. Conclusion：Protease combined with mechanical trituration may be used for the dissociation of neurons from rat hippocampus. Voltage-gated channels currents could be recorded using a patch clamp technique.展开更多
BACKGROUND： Prenatal stress has been shown to inhibit cell proliferation in the dentate gyrus and hippocampus, reduce hippocampal volume, and cause neuronal loss and oxidative damage in the hippocampus of offspring r...BACKGROUND： Prenatal stress has been shown to inhibit cell proliferation in the dentate gyrus and hippocampus, reduce hippocampal volume, and cause neuronal loss and oxidative damage in the hippocampus of offspring rats, but the sexual difference of the effects on offsprings is seldom referred to. OBJECTIVE： To observe the effect of prenatal stress to adult pregnant rats on expression of extracellular signal-regulated kinases （ERK） in hippocampus of the offspring rats of different genders. DESIGN ： A randomized and control animal experiment.SETTING： Department of Physiology and Pathophysiology, School of Medicine, Xi＇an Jiaotong University. MATERIALS ： The experiments were carried out in the Key Laboratory of Environment and Gene Related Diseases （Xi＇an Jiaotong University）, Ministry of Education between October 2005 and March 2006. Fifteen female and five male adult Sprague-Dawley rats were adopted. Female rats weighing 230-250 g and male rats weighing 280-350 g were used. METHODS： The virgin female rats were placed overnight with adult male rats （3：1） for mating. A total of twelve pregnant rats were randomly assigned to prenatal stress group （PNS group, n=6） and control group （n=6）. The pregnant rats of the PNS group were exposed to restraint stress on days 14-20 of pregnancy three times a day, 45 minutes for each time . The restraint device was a transparent plastic tube （6.8 cm in diameter） with air holes for breathing and closed end. The length could be adjusted to accommodate the size of the animals. To prevent habituation of animals to the daily procedure, restraint periods were randomly shifted within certain time periods （8：00-11：00, 11：00-14：00, and 16：00-19：00）. After birth, offsprings of all groups were culled to 8-10 litters in each group and housed in the same animal room, and kept together with their biologic mothers. The pregnant rats of the control group were left undisturbed. On day 21, after all the offspring were weaned, male and female pups were separated and housed four in each cage respectively until test at 30 days of age. At the end of postnatal day 30, one male and female offspring rats from the same dam were selected with a random choice and a total of 24 animals from 12 different dams were used. The experimental rats were sacrificed by decapitation under anesthesia. Bilateral hippocampal tissues were isolated and homogenized in cold condition. Alkaline carbonate buffer （BCA） method was used to detect the concentration of extracellular signal-regulated kinases （ERK）, then mixed with loading buffer, the constant voltage was 100 V. Finally, BCIP/NBT staining and electrDphoresis were performed, the absorbance （A） value for the bands was detected with the Bandscan analytical software, and the expression of ERK in hippocampus of offspring rats of different genders in each group was quantitatively analyzed. MAIN OUTCOME MEASURES： The level of ERK expression in hippocampus of offspring rats of different genders in each group was observed.RESULTS： All the 24 offspring rats were involved in the analysis of results. ① The staining results of ERP activity in the extract of brain tissue detected with Western blotting technique and specific antibody analysis showed that the ERP in hippocampus of offspring rats had two subtypes of ERK-1 and ERK-2, and the latter was the main type.② Standardized by the average A value in the control group, the quantitative data of the general A value of total ERK showed that the expression of ERK-2 in hippocampus of female offspring rats was obviously higher in the PNS group than in the control group （A value： 126±6.76,100±4.89,P〈 0.01）. ③The expression of ERK-2 had no obvious difference between the female and male offspring rats in the control group.④ The expression of ERK-2 in hippocampus of male offspring rats was a little higher in the PNS group than in the control group （A value： 104±6.27,102±5.48,P 〉 0.05）. CONCLUSION ： PNS significantly affects the increase of ERK expression in hippocampus of female offspring rats, but has no obvious influence on that of male ones.展开更多
To the Editor:Chronic obstructive pulmonary disease(COPD),characterized by progressive airflow limitation and persistent respiratory symptoms,remains a leading cause of global morbidity and mortality.Current estimates...To the Editor:Chronic obstructive pulmonary disease(COPD),characterized by progressive airflow limitation and persistent respiratory symptoms,remains a leading cause of global morbidity and mortality.Current estimates indicate a global COPD prevalence of 4–10%,with a mortality rate of approximately 3%.[1]Pulmonary rehabilitation(PR)is widely recognized as one of the most cost-effective therapeutic interventions for COPD.[2]A recent study[3]demonstrated that PR plays a pivotal role in the long-term management of COPD.However,robust evidence regarding the efficacy of telemedicine-based pulmonary rehabilitation(PTR)interventions remains limited.This meta-analysis evaluates the clinical outcomes of PTR compared to conventional PR in COPD patients.展开更多
文摘Three sets of MXene(Ti_(3)C_(2)T_(x))@nano-Fe_(1)Co_(0.8)Ni_(1)composites with 15,45,and 90 mg MXene were prepared by in-situ liquid-phase deposition to effectively investigate the impact of the relationship between MXene(Ti_(3)C_(2)T_(x))and nano-Fe_(1)Co_(0.8)Ni_(1)magnetic particles on the electromagnetic absorption properties of the composites.The microstructure,static magnetic properties,and electromag-netic absorption performance of these composites were studied.Results indicate that the MXene@nano-Fe_(1)Co_(0.8)Ni_(1)composites were primarily composed of face-centered cubic crystal structure particles and MXene,with spherical Fe_(1)Co_(0.8)Ni_(1)particles uniformly distrib-uted on the surface of the multilayered MXene.The alloy particles had an average particle size of approximately 100 nm and exhibited good dispersion without noticeable particle aggregation.With the increase in MXene content,the specific saturation magnetic and coer-civity of the composite initially decreased and then increased,displaying typical soft magnetic properties.Compared with those of the Fe_(1)Co_(0.8)Ni_(1)magnetic alloy particles alone,MXene addition caused an increasing trend in the real and imaginary parts of the dielectric constant of the composite.Meanwhile,the real and imaginary parts of the magnetic permeability exhibit decreasing trend.With the in-crease in MXene addition,the material attenuation constant increased and the impedance matching decreased.The minimum reflection loss increased,and the maximum effective absorption bandwidth decreased.When the MXene addition was 90 mg,the composite exhib-ited a minimum reflection loss of-46.9 dB with a sample thickness of 1.1 mm and a maximum effective absorption bandwidth of 3.60 GHz with a sample thickness of 1.0 mm.The effective absorption bandwidth of the composites and their corresponding thicknesses showed a decreasing trend with the increase in MXene addition,reducing by 50%from 1.5 mm without MXene addition to 1 mm with 90 mg of MXene addition.
基金This work was supported by SUG Research Grant M4082126.050 by the School of Mechanical and Aerospace Engineering(MAE),Nanyang Technological University(NTU),SingaporeNTU-CAAS Research Grant M4062429.052 by the ATM Research Institute,School of MAE,NTU,Singapore.
文摘Intractable delays occur in air traffic due to the imbalance between ever-increasing air traffic demand and limited airspace capacity.As air traffic is associated with complex air transport systems,delays can be magnified and propagated throughout these systems,resulting in the emergent behavior known as delay propagation.An understanding of delay propagation dynamics is pertinent to modern air traffic management.In this work,we present a complex network perspective of delay propagation dynamics.Specifically,we model air traffic scenarios using spatial–temporal networks with airports as the nodes.To establish the dynamic edges between the nodes,we develop a delay propagation method and apply it to a given set of air traffic schedules.Based on the constructed spatial-temporal networks,we suggest three metrics-magnitude,severity,and speed-to gauge delay propagation dynamics.To validate the effectiveness of the proposed method,we carry out case studies on domestic flights in the Southeastern Asia region(SAR)and the United States.Experiments demonstrate that the propagation magnitude in terms of the number of flights affected by delay propagation and the amount of propagated delays for the US traffic are respectively five and ten times those of the SAR.Experiments further reveal that the propagation speed for US traffic is eight times faster than that of the SAR.The delay propagation dynamics reveal that about six hub airports in the SAR have significant propagated delays,while the situation in the United States is considerably worse,with a corresponding number of around 16.This work provides a potent tool for tracing the evolution of air traffic delays.
基金supported by Scientific Research Fund of Sichuan Provincial Education Department(13ZC0004)
文摘FeGa alloy is a new kind of magnetostrictive material, and rare-earth cerium can improve its magnetostrictive property.（Fe（81）Ga（19））（100-x）Cex（x = 0, 0.3 at%, 0.7 at%, 1 at%） samples were prepared by doping cerium in Fe（81）Ga（19） alloy. Their microstructures and phases were studied, and valence electronic structures were investigated. Electromagnetic parameters, such as coercivity, saturation magnetization,remnant magnetization and saturation magnetostrictive coefficients（λs） of every sample were measured.Cerium atoms are distributed at grain boundaries, and the Ce-doped alloys remain the A2 structure of FeGa alloy. When x is 0.7, the value of saturation magnetism is 217.08 emu/g, which is the maximum in the Ce-doped samples. The equivalent half length of single bond is the maximum also, and reaches to0.11380 nm. At the same time, the number of covalent electrons is 3.5672, and is the minimum of the Cedoped samples. Its As is the largest in the four samples. The change of As results in the change of equivalent half length of single bond in Ce-doped alloy.
基金supported by the National Natural Science Foundation of China under Grants 61922062 and 61873181。
文摘Gas-liquid two-phase flow widely exits in production and transportation of petroleum industry.Characterizing gas-liquid flow and measuring flow parameters represent challenges of great importance,which contribute to the recognition of flow regime and the optimal design of industrial equipment.In this paper,we propose a novel complex network-based deep learning method for characterizing gas-liquid flow.Firstly,we map the multichannel measurements to multiple limited penetrable visibility graphs(LPVGs)and obtain their degree sequences as the graph representation.Based on the degree distribution,we analyze the complicated flow behavior under different flow structures.Then,we design a dual-input convolutional neural network to fuse the raw signals and the graph representation of LPVGs for the classification of flow structures and measurement of gas void fraction.We implement the model with two parallel branches with the same structure,each corresponding to one input.Each branch consists of a channel-projection convolutional part,a spatial-temporal convolutional part,a dense block and an attention module.The outputs of the two branches are concatenated and fed into several full connected layers for the classification and measurement.At last,our method achieves an accuracy of 95.3%for the classification of flow structures,and a mean squared error of 0.0038 and a mean absolute percent error of 6.3%for the measurement of gas void fraction.Our method provides a promising solution for characterizing gas-liquid flow and measuring flow parameters.
基金Sponsored by the National Natural Science Foundation of China(Grant No.51138003)
文摘In order to estimate vehicular queue length at signalized intersections accurately and overcome the shortcomings and restrictions of existing studies especially those based on shockwave theory,a new methodology is presented for estimating vehicular queue length using data from both point detectors and probe vehicles. The methodology applies the shockwave theory to model queue evolution over time and space. Using probe vehicle locations and times as well as point detector measured traffic states,analytical formulations for calculating the maximum and minimum( residual) queue length are developed. The proposed methodology is verified using ground truth data collected from numerical experiments conducted in Shanghai,China. It is found that the methodology has a mean absolute percentage error of 17. 09%,which is reasonably effective in estimating the queue length at traffic signalized intersections. Limitations of the proposed models and algorithms are also discussed in the paper.
文摘With the advancement of Communication,Navigation and Surveillance(CNS)technolo-gies such as space-based Automatic Dependent Surveillance-Broadcast/Contract(ADS-B/C),large separation minima may be reduced in procedural airspaces.It is of great significance to know the upper limit of the Reduced Separation Minima(RSM)for a procedural airspace and the corre-sponding consequences on collision risk with specifics of the advanced ADS-B and control interven-tion model.In this work,an interactive software is first developed for collision risk estimation.This software integrates the International Civil Aviation Organization(ICAO)collision risk models for lateral and longitudinal collision risk calculation for the Singapore procedural airspace.Results demonstrate that the lateral and longitudinal collision risk of Singapore procedural airspace with respect to current control procedures meets the ICAO Target Level of Safety(TLS)standard.Moreover,the feasibility of reducing the horizontal separations implemented in the Singapore pro-cedural airspace with respect to advanced CNS techniques is investigated.It is found that if advanced CNS technologies are applied,then the current 50-NM lateral and longitudinal separa-tion standards can be reduced to 22 NM(1 NM=1.825 km)and 20 NM,respectively,to meet the TLS standards based on current demand.A method is then devised to expand the traffic demand by p for p∈[10%,200%].It is found that the minimum lateral and longitudinal separa-tions can be reduced from 50 NM to be within the range of[23,31]NM,and 20 NM,respectively,for p∈[10%,200%],while the collision risk still meets the TLS standards.
文摘Objective: To observe the clinical efficacy and safety of low dose tacrolimus (TAC) combined with tripterygium (TW) in treatment of steroid resistant nephritic syndrome (SRNS). Method: The patients, who were diagnosed with mesangial proliferative glomerulonephritis (MesPGN) and focal segmental glomerulosclerosis (FSGS) by biopsy and failed to respond to a 3-month treatment with prednisone (1 mg/kg·d), were randomly divided into 2 groups (TAC + TW Group and TW Group). Initially TAC + TW group took TAC 0.05mg/(kg·d) 2 h after meal at 12 h interval. The plasma TAC level was examined after 3 days and was kept at 1.5 - 4 ng·ml;meanwhile, TW was given at 60 mg/d before meal. TW group only took TW (60 mg/d). The efficacy, adverse reactions and plasma TAC levels were observed in each group. Results: 1) Totally 20 SRNS patients completed the trial, 11 of TAC + TW Group and 9 of TW Group. There is no statistical difference between the two groups in terms of age, gender, duration since onset of the disease, blood pressure, 24 h UPQ, serum albumin, creatinine, cholesterol, triglyceride, FBG, kidney pathological categories, time of taking prednisone etc.;2) Urine protein started to decrease after 1 month treatment in both of TAC + TW and TW groups. By the 12th month of treatment, TAC + TW group showed 8 cases of complete remission (72.7%), 2 cases of partial remission (18.2%) and 1 case of no improvement (9.1%), while those of TW groups were 2 (22.2%), 4 (44.5%) and 3 (33.3%), respectively;3) With treatment, the TAC + TW Group patients’ plasma protein was significantly higher than that of pretreatment stage and recovered to normal level after 6 month of treatment. However, there was no significant plasma protein increase in TW Group. No obvious changes were observed on serum creatinine level of patients of both the two groups;4) The incidence of adverse reactions was not significantly different between the two groups. Conclusion: TAC + TW reduced proteinuria of SRNS patients, increased clinical remission rate and was tolerant to SRNS patients. We conclude that TAC + TW treatment is an effective way to treat patients with SRNS.
文摘Recent studies have made substantial progress in understanding the interactions between cognitive functions, from language to cognitive control, attention, and memory. However, dissociating these functions has been hampered by the close proximity of regions involved, as in the case in the prefrontal and parietal cortex. In this article, we review a series of studies that investigated the relationship between language and other cognitive functions in an alternative way - by examining their functional （co-）lateralization. We argue that research on the hemispheric lateralization of language and its link with handedness can offer an appropriate starting- point to shed light on the relationships between different functions. Besides functional interactions, anatomical asymmetries in non-human primates and those underlying language in humans can provide unique information about cortical organization. Finally, some open questions and criteria are raised for an ideal theoretical model of the cortex based on hemispheric specialization.
文摘BACKGROUND：Carotid intima media thickness （CIMT） and stiffness are taken as useful surrogate markers of atherosclerosis. In China, the number of elderly patients undergoing hemodialysis has increased year by year, with the increase of dialysis-related cardiovascular events. This study was undertaken to examine carotid stiffness in elderly hemodialysis patients by the ultrasound techniques in order to find out the possible risk factors. From January 2006 to February 2010, a total of 87 patients （41 males and 46 females） treated with routine hemodialysis at the 97th Hospital of People＇s Liberation Army were enrolled in this study. The distensibility coefficient （DC） of the carotid artery was detected by Doppler ultrasonic diagnosis apparatus （Philips HBI5000, frequency 12 MHz） for evaluation of arterial stiffness. Serum albumin, total cholesterol （TC）, high density lipoprotein （HDL）, low density lipoprotein （LDL）, triglyceride （TG）, glucose, creatinine, calcium, phosphorus, and intact parathyroid hormone （iPTH） were examined with standard methods. The liner correlation and multiple stepwise regression analysis were used to find correlations between them. RESULTS： In this study, the systolic blood pressure was 153.33±25.98 mmHg, DBP 84.22± 10.39 mmHg, TC 4.39±1.05 mmol/L, TG 1.36±0.72 mmol/L, LDL 2.47±0.77 mmol/L, Cr 889.82± 207.38 μmol/L, Glu 5.36±1.87 mmol/L, Ca 12.00±2.19±0.21 mmol/L, and DC 13.39±5.32×10-3/kPa. DC was associated with age （r =-0.459, P〈0.001）, SBP （r =-0.527, P〈0.001）, and serum calcium （r =-0.273, P=0.011）. The multiple stepwise regression analysis showed that SBP, age, increased serum calcium level, and diabetes were independent risk factors for decreasing DC. CONCLUSION： Systolic blood pressure, age, increased serum calcium level and diabetes in elderly hemodialysis patients are independent risk factors for increased carotid arterial stiffness.
基金supported by the National Key R&D Program of China(Grant No.2022YFB3605403)the Natural Science Foundation of Jiangsu Province(Grant Nos.BK20200094 and BK20210577)+3 种基金the National Natural Science Foundation of China(Grant Nos.62004104 and 62104110)the Natural Science Foundation of the Jiangsu Higher Education Institutions of China(Grant No.21KJB140020)the Jiangsu Provincial Double-Innovation Doctor Program(Grant No.JSSCBS20210529)the Natural Science Foundation of Jiangsu Province-Major Project(Grant No.BK20212012).
文摘The AlGaN/GaN p-n junction has received extensive attention due to its capability of rapid photogenerated carrier separation in photodetection devices.The AlGaN/GaN heterojunction nanowires(NWs)have been especially endowed with new life for distinctive transport characteristics in the photoelectrochemical(PEC)detection field.A self-powered PEC ultraviolet photodetector(PEC UV PD)based on the p-AlGaN/n-GaN heterojunction NW is reported in this work.The n-GaN NW layer plays a crucial role as a current flow hub to regulate carrier transport,which mainly acts as a light absorber under 365 nm and carrier recombination layer under 255 nm illumination,which can effectively modulate photoresponsivity at different wavelengths.Furthermore,by designing the thicknesses of the NW layer,the photocurrent polarity reversal was successfully achieved in the constructed AlGaN/GaN NW PEC UV PD at two different light wavelengths.In addition,by combining with platinum decoration,the photoresponse performance could be further enhanced.Our work provides insight into transport mechanisms in the AlGaN/GaN NW PEC system,and offers a feasible and comprehensive strategy for further exploration of multifunctional optoelectronic devices.
基金Project supported by the National Key Research and Development Program of China(Grant No.2017YFB0402900)the National Natural Science Foundation of China(Grant No.61634002)+1 种基金the Scientific Research Foundation of Graduate School of Nanjing University,China(Grant No.2016CL03)the Key Project of Jiangsu Province,China(Grant No.BE2016174)
文摘We investigate the negative transconductance effect in p-GaN gate AlGaN/GaN high-electron-mobility transistor(HEMT) associated with traps in the unintentionally doped GaN buffer layer. We find that a negative transconductance effect occurs with increasing the trap concentration and capture cross section when calculating transfer characteristics.The electron tunneling through AlGaN barrier and the reduced electric field discrepancy between drain side and gate side induced by traps are reasonably explained by analyzing the band diagrams, output characteristics, and the electric field strength of the channel of the devices under different trap concentrations and capture cross sections.
基金the Natural Science Research Project of Anhui University,China(Grant No.KJ2019A0644)the National Natural Science Foundation of China(Grant Nos.61634002 and 61804089)+3 种基金the Natural Science Alliance Foundation,China(Grant No.U1830109)the Natural Science Foundation of Anhui Province,China(Grant No.1708085MF149)the Chuzhou University Research Project,China(Grant No.zrjz2019002)the Project of the Higher Educational and Technology Program of Shandong Province,China(Grant No.J16LN04).
文摘To suppress the electric field crowding at sidewall and improve the detection sensitivity of the AlGaN separate absorption and multiplication(SAM)avalanche photodiodes(APDs),we propose the new AlGaN APDs structure combining a large-area mesa with a field plate(FP).The simulated results show that the proposed AlGaN APDs exhibit a significant increase in avalanche gain,about two orders of magnitude,compared to their counterparts without FP structure,which is attributed to the suppression of electric field crowding at sidewall of multiplication layer and the reduction of the maximum electric field at the p-type GaN sidewall in p-n depletion region.Meanwhile,the APDs can produce an obviously enhanced photocurrent due to the increase in cross sectional area of multiplication region.
基金Supported by Shandong Province Land and Resources Survey Project(2006709)Ministry and Province Cooperation Project(1212010310306)
文摘Based on a comprehensive eco-geochemical survey of Shandong Province,the differences in pesticide residue situation and contents of DDTs and HCHs in the soils of Yantai City and Southwest Shandong Province(abbreviated as SSP)were studied in this paper.The results showed that the detection rates of DDTs and HCHs in the soil of SSP were apparently higher than Yantai City.However,the mean contents of DDTs and HCHs in the soil of Yantai were 9 and 25 times of SSP,respectively,and higher than the mean contents of many other cities and areas.p,p′-DDE was the main pesticide residual form in the soil of SSP.It is recognized as the degradation product of DDTs in oxidation environment in past,nevertheless,5.52%of the soils in Yantai City still have a little of DDT input recently,which has posed a big impact on soil environment quality.β-HCH was the main form of the four isomers of HCHs in Yantai City,andα-HCH/γ-HCH in SSP was low.These reveal that the residual time of HCHs in the soils of both the two areas has a long period.After primary analysis,the risk of DDTs and HCHs in the soil of SSP is low,but DDTs in the soil of Yantai City still has a certain risk.
基金Supported by Special Project of Basic Scientific and Technological Research of the State Ministry of Science and Technology in the Eleventh Five-Year Plan Period(2006FY110700)China Agriculture Research System(CARS-25)National Crop Germplasm Resource Platform
文摘In 2007- 2008,a systematic survey,collection and arrangement was carried out for agricultural biological resources and traditional cultural knowledge of Hani People in 8 counties,15 towns,and 23 village committees of Yunnan Province. A total of 299 samples were obtained about agricultural biological resources related to production and living of Hani People. According to purpose of utilization,samples were divided into grain crops,medicinal plants,vegetables,fruit trees,and oil crops,taking up 48. 2%,21. 7%,18. 4%,7. 7%,and 2. 0% of the samples respectively. The survey indicated that planting industry and breeding industry take up the dominant role in rural social economy of Hani People,so agricultural biological resources are the fundamental means of production maintaining rural social development of Hani People.The current situation of agricultural biological resources of Hani People in Yunnan,reasons for growth and decline were analyzed,and the utilization,protection and development of agricultural biological resources were discussed.
基金Supported Sub-project of"Land Quality Geochemical Survey of Beijing-Tianjin-Hebei-Lugeng Area"Project of Tianjin Geological Survey Center of China Geological Survey(DD20160325-03).
文摘The land quality geochemical evaluation database was mainly based on soil geochemical surveys.During its construction process,geochemical survey data involving atmospheric dry(wet)sediments,irrigation water,fertilizers and crops was simultaneously collected,analyzed and compiled into result maps using MAPGIS.ACCESS was used to manage standardized result data to establish an evaluation database.The database included a basic spatial database involving regional geography,topography,soil type and land use,a spatial evaluation database centered on the sampling layout of the work areas of soil,irrigation water,crops and other media,the distribution and changes of soil chemical elements,the classification of soil pollution and the classification of soil element environment and nutrients,and an evaluation database of various result maps such as land planning map,characteristic agricultural product planting plan suggestion map and fertilization suggestion map.The database realized the scientific and effective management of the samples and corresponding numerous laboratory analysis data,and provides basic information for the geochemical survey and evaluation of the land quality in the evaluation areas and the overall comprehensive research,and an important basis for promoting the adjustment of agricultural economic planning,the development of modern green agriculture and the development and utilization of high-quality characteristic land resources.
基金supported by Science Development Foundation of Tianjin Institute of Education(20070301)
文摘Objective：To record Calcium, Potassium and Sodium currents in acutely isolated hippocampal pyramidal neurons. Methods：Hippocampal CA3 neurons were freshly isolated by 1 mg protease/3 ml SES and mechanical trituration with polished pipettes of progressively smaller tip diameters. Patch clamp technique in whole-cell mode was employed to record voltage-gated channel currents. Results：The procedure dissociated hippocampal neurons, preserving apical dendrites and several basal dendrites, without impairing the electrical characteristics of the neurons. Whole-cell patch clamp configuration was successfully used to record voltage-gated Ca^2＋ currents, delayed rectifier K^＋ current and voltage-gated Na^＋ currents. Conclusion：Protease combined with mechanical trituration may be used for the dissociation of neurons from rat hippocampus. Voltage-gated channels currents could be recorded using a patch clamp technique.
基金the National Natural Science Foundation of China, No. 30270445
文摘BACKGROUND： Prenatal stress has been shown to inhibit cell proliferation in the dentate gyrus and hippocampus, reduce hippocampal volume, and cause neuronal loss and oxidative damage in the hippocampus of offspring rats, but the sexual difference of the effects on offsprings is seldom referred to. OBJECTIVE： To observe the effect of prenatal stress to adult pregnant rats on expression of extracellular signal-regulated kinases （ERK） in hippocampus of the offspring rats of different genders. DESIGN ： A randomized and control animal experiment.SETTING： Department of Physiology and Pathophysiology, School of Medicine, Xi＇an Jiaotong University. MATERIALS ： The experiments were carried out in the Key Laboratory of Environment and Gene Related Diseases （Xi＇an Jiaotong University）, Ministry of Education between October 2005 and March 2006. Fifteen female and five male adult Sprague-Dawley rats were adopted. Female rats weighing 230-250 g and male rats weighing 280-350 g were used. METHODS： The virgin female rats were placed overnight with adult male rats （3：1） for mating. A total of twelve pregnant rats were randomly assigned to prenatal stress group （PNS group, n=6） and control group （n=6）. The pregnant rats of the PNS group were exposed to restraint stress on days 14-20 of pregnancy three times a day, 45 minutes for each time . The restraint device was a transparent plastic tube （6.8 cm in diameter） with air holes for breathing and closed end. The length could be adjusted to accommodate the size of the animals. To prevent habituation of animals to the daily procedure, restraint periods were randomly shifted within certain time periods （8：00-11：00, 11：00-14：00, and 16：00-19：00）. After birth, offsprings of all groups were culled to 8-10 litters in each group and housed in the same animal room, and kept together with their biologic mothers. The pregnant rats of the control group were left undisturbed. On day 21, after all the offspring were weaned, male and female pups were separated and housed four in each cage respectively until test at 30 days of age. At the end of postnatal day 30, one male and female offspring rats from the same dam were selected with a random choice and a total of 24 animals from 12 different dams were used. The experimental rats were sacrificed by decapitation under anesthesia. Bilateral hippocampal tissues were isolated and homogenized in cold condition. Alkaline carbonate buffer （BCA） method was used to detect the concentration of extracellular signal-regulated kinases （ERK）, then mixed with loading buffer, the constant voltage was 100 V. Finally, BCIP/NBT staining and electrDphoresis were performed, the absorbance （A） value for the bands was detected with the Bandscan analytical software, and the expression of ERK in hippocampus of offspring rats of different genders in each group was quantitatively analyzed. MAIN OUTCOME MEASURES： The level of ERK expression in hippocampus of offspring rats of different genders in each group was observed.RESULTS： All the 24 offspring rats were involved in the analysis of results. ① The staining results of ERP activity in the extract of brain tissue detected with Western blotting technique and specific antibody analysis showed that the ERP in hippocampus of offspring rats had two subtypes of ERK-1 and ERK-2, and the latter was the main type.② Standardized by the average A value in the control group, the quantitative data of the general A value of total ERK showed that the expression of ERK-2 in hippocampus of female offspring rats was obviously higher in the PNS group than in the control group （A value： 126±6.76,100±4.89,P〈 0.01）. ③The expression of ERK-2 had no obvious difference between the female and male offspring rats in the control group.④ The expression of ERK-2 in hippocampus of male offspring rats was a little higher in the PNS group than in the control group （A value： 104±6.27,102±5.48,P 〉 0.05）. CONCLUSION ： PNS significantly affects the increase of ERK expression in hippocampus of female offspring rats, but has no obvious influence on that of male ones.
基金This work was supported by the University Science and Technology Innovation Team(No.YKD2022TD013)Joint Fund Project of Natural Science Foundation of Inner Mongolia Autonomous Region(No.2023LHMS08062)the Science and Technology Program of Inner Mongolia Autonomous Region(No.2022YFSH0002).
文摘To the Editor:Chronic obstructive pulmonary disease(COPD),characterized by progressive airflow limitation and persistent respiratory symptoms,remains a leading cause of global morbidity and mortality.Current estimates indicate a global COPD prevalence of 4–10%,with a mortality rate of approximately 3%.[1]Pulmonary rehabilitation(PR)is widely recognized as one of the most cost-effective therapeutic interventions for COPD.[2]A recent study[3]demonstrated that PR plays a pivotal role in the long-term management of COPD.However,robust evidence regarding the efficacy of telemedicine-based pulmonary rehabilitation(PTR)interventions remains limited.This meta-analysis evaluates the clinical outcomes of PTR compared to conventional PR in COPD patients.
