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Effects of different moxibustion durations on lumbar disk herniation:a clinical study
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作者 Bin Chen Ting Yang Chun-Qin Zhu 《Frontiers of Nursing》 2024年第1期47-56,共10页
Objective:To explore the best duration of moxibustion on lumbar disk herniation(LDH).Methods:A total of 88 patients were randomly divided into control group and 15-min,30-min,and 45-min moxibustion groups.The control ... Objective:To explore the best duration of moxibustion on lumbar disk herniation(LDH).Methods:A total of 88 patients were randomly divided into control group and 15-min,30-min,and 45-min moxibustion groups.The control group was treated with conventional therapy,while the other 3 groups were intervened with different moxibustion durations.Low back pain,dysfunction,lumbar function,and effective rates were evaluated before,in the first week and second week of intervention.Results:In low back pain,compared with the control group,the score of the 15-min group had no significant difference,but it was significantly lower in the 30-min and 45-min groups.In dysfunction and lumbar function,compared with the control group,the scores of the 15-min,30-min,and 45-min groups were significantly higher,and the scores of the 30-min and 45-min groups were significantly higher,but there was no significant difference between the 30-min and 45-min group.In effective rates,there was no significant difference between the control group and 15-min group;the effective rates of the 30-min and 45-min groups were significantly higher than those of the control group.Conclusions:Moxibustion has good therapeutic effect on LDH with specific moxibustion time. 展开更多
关键词 duration of moxibustion lumbar disc herniation MOXIBUSTION
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Study on Developmental Durations and Fecundity of Phenacoccus solenopsis Tinsley on Four Species of Hosts 被引量:8
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作者 关鑫 陆永跃 曾玲 《Agricultural Science & Technology》 CAS 2012年第2期408-411,共4页
[Objective] The aim was to study on the effect of hosts on development and reproduction of mealybug (Phenacoccus solenopsis Tinsley). [Method] Observation was conducted on developmental durations and fecundity of Ph... [Objective] The aim was to study on the effect of hosts on development and reproduction of mealybug (Phenacoccus solenopsis Tinsley). [Method] Observation was conducted on developmental durations and fecundity of Phenacoccus solenopsis Tinsley fed on Gossypium spp., Nicotiana tabacum, Solanum tuberosum L and Hibiscus rosa-sinensis. [Result] There were differences among all durations, generation durations and fecundities of the mealybug adult females. Specifically, the generation durations on cotton (Gossypium spp.), tobacco( Nicotiana tabacum), potato (Solanum tuberosum L) and Hibiscus rosa-sinensis were 30.2, 28.2, 37.3, and 27.7 d, and the fecundities per female were 626.0, 417.2, 552.5, and 183.2 ind., respectively. [Conclusion] The mealybug would have strong pontential in population growth when fed on cotton, tobacco and potato. 展开更多
关键词 Phenacoccus solenopsis Tinsley Host plants Development duration FECUNDITY
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Therapeutic effects of different durations of acupuncture on rats with middle cerebral artery occlusion 被引量:17
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作者 Chao Zhang Yan Wen +4 位作者 Xiao-nong Fan Guang Tian Xue-yi Zhou Shi-zhe Deng Zhi-hong Meng 《Neural Regeneration Research》 SCIE CAS CSCD 2015年第1期159-164,共6页
Acupuncture is regarded as an effective therapy for cerebral ischemia. Different acupuncture ma- nipulations and durations may result in different therapeutic effects. In the present study, the Neig uan (PC6) acupoi... Acupuncture is regarded as an effective therapy for cerebral ischemia. Different acupuncture ma- nipulations and durations may result in different therapeutic effects. In the present study, the Neig uan (PC6) acupoint of rats with occluded middle cerebral arteries was needled at a fixed frequency (3 Hz) with different durations, i.e., 5, 60 and 180 seconds under a twisting-rotating acupuncture method. Results showed that different durations of acupuncture had different therapeutic effects, with 60 seconds yielding a better therapeutic effect than the other two groups. This duration of treatment demonstrated rapid cerebral blood flow, encouraging recovery of neurological function, and small cerebral infarct volume. Experimental findings indicated that under 3 Hz frequency, the treatment of needling Neiguan for 60 seconds is effective for ischemic stroke. 展开更多
关键词 nerve regeneration middle cerebral artery occlusion MANIPULATION NEIGUAN cerebralinfarction volume twisting-rotating method DURATION frequency cerebral blood flow neural regeneration
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Comparative effectiveness research on incision healing after lumbar spinal surgery with different TDP irradiation durations 被引量:2
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作者 Feng Xiao Ren-Lian Jiang +1 位作者 Jun-Ru Chen Xue-Mei Long 《Frontiers of Nursing》 CAS 2018年第4期273-276,共4页
Objective: This research aims to investigate the best "Te Ding Dian Ci Bo Pu Zhi Liao Qi"(TDP) irradiation duration to enhance the efficacy of nursing and patient satisfaction.Methods: A total of 34 eligible... Objective: This research aims to investigate the best "Te Ding Dian Ci Bo Pu Zhi Liao Qi"(TDP) irradiation duration to enhance the efficacy of nursing and patient satisfaction.Methods: A total of 34 eligible patients were randomly divided into the treatment group(n=18) and the control group(n=16) between December 2015 and December 2016. Qualitative and quantitative studies were combined to create an impersonal evaluation of incision pain score, time of stitches removal, duration of hospital stays, patient satisfaction, and subjective experience due to different TDP irradiation durations.Results: The incision pain scores of the treatment group were 3.06±0.899 and 1.35±0.493 before and after treatment, respectively(P< 0.05), whereas those of the control group were 2.46±1.127 and 1.0±0.707 before and after treatment, respectively(P<0.05).No significant difference was found between the treatment group and the control groupup(P>0.05). The time of stitches removal and the duration of hospital stays of the treatment group were 14.85±4.070 and 19.08±6.652, respectively, whereas those of the control group were 14.08±0.641 and 23.15±10.72(P>0.05), respectively. The patient satisfaction degree score of the treatment group was2.77±0.439, whereas that of the control group was 2.08±0.954(P< 0.05).Conclusions: TDP irradiation can effectively relieve the incision pain of patients after lumbar spinal surgery. The treatment group is superior to the control group in patient satisfaction. 展开更多
关键词 TDP TDP irradiation duration patient satisfaction lumbar operation TIME incision pain PHYSIOTHERAPY
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Daily Activities and Sleep Durations of Patients with Ischemic Heart Disease Who Were Discharged to Their Homes after Elective Percutaneous Coronary Intervention 被引量:2
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作者 Yuko Yasuhara Tetsuya Tanioka +3 位作者 Rozzano Locsin Waraporn Kongsuwan Beth King Haruo Kobayashi 《Open Journal of Psychiatry》 2017年第4期318-328,共11页
The purpose of this study was to examine the relationship between daily activities and sleep durations for patients following elective percutaneous coronary intervention (ePCI) and diagnosed with ischemic heart diseas... The purpose of this study was to examine the relationship between daily activities and sleep durations for patients following elective percutaneous coronary intervention (ePCI) and diagnosed with ischemic heart disease (IHD) after discharge to their homes. The actigraph data were used to collect data from twenty five patients. The duration of night-time sleep (minutes from the start to end of night-time) and actual night-time sleep duration (total sleep duration excluding wake-up durations of night-time) on the seventh day after discharge were divided into three groups;less than 360, 360 to 480, and more than 480 minutes (short, optimal and long respectively). Subsequently, among the three groups of patients, the data were analyzed by Kruskal Wallis H-test with multiple comparison procedures using the Scheffé-test in order to compare differences in daytime activity items at seven days after discharge from the hospital. Total daytime nap duration (p p p p < 0.05). However, the duration of night-time sleep and daytime activity did not significantly differ. If actual night-time sleep duration is improved from 360 to 480 minutes, daytime nap could potentially be decreased. Determining objective sleep conditions for patients and treating sleep disorders may improve overall patient health, facilitating appropriate sleep and wake rhythms. 展开更多
关键词 ACTIGRAPHY ELECTIVE PERCUTANEOUS CORONARY Intervention Actual Night-Time Sleep Duration Daily Activity
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High room-temperature magnetization in Co-doped TiO_(2) nanoparticles promoted by vacuum annealing for different durations 被引量:1
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作者 Wenqiang Huang Rui Lin +2 位作者 Weijie Chen Yuzhu Wang Hong Zhang 《Journal of Semiconductors》 EI CAS CSCD 2021年第7期71-77,共7页
To clarify the contribution of oxygen vacancies to room-temperature ferromagnetism(RTFM)in cobalt doped TiO_(2)(Co-TiO_(2)),and in order to obtain the high level of magnetization suitable for spintronic devices,in thi... To clarify the contribution of oxygen vacancies to room-temperature ferromagnetism(RTFM)in cobalt doped TiO_(2)(Co-TiO_(2)),and in order to obtain the high level of magnetization suitable for spintronic devices,in this work,Co-TiO_(2) nano-particles are prepared via the sol-gel route,followed by vacuum annealing for different durations,and the influence of vacu-um annealing duration on the structure and room-temperature magnetism of the compounds is examined.The results reveal that with an increase in annealing duration,the concentration of oxygen vacancies rises steadily,while the saturation magnetiza-tion(Ms)shows an initial gradual increase,followed by a sharp decline,and even disappearance.The maximum Ms is as high as 1.19 emu/g,which is promising with respect to the development of spintronic devices.Further analysis reveals that oxygen va-cancies,modulated by annealing duration,play a critical role in tuning room-temperature magnetism.An appropriate concentra-tion of oxygen vacancies is beneficial in terms of promoting RTFM in Co-TiO_(2).However,excessive oxygen vacancies will result in a negative impact on RTFM,due to antiferromagnetic superexchange interactions originating from nearest-neighbor Co^(2+)ions. 展开更多
关键词 Co-doped TiO_(2)nanoparticles room-temperature ferromagnetism different annealing duration oxygen vacancy high magnetization
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Clinical Characteristics and Durations of Hospitalized Patients with COVID-19 in Beijing: A Retrospective Cohort Study
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作者 Wen Zhao Xiangyi Zha +3 位作者 Ning Wang Dongzeng Li Aixin Li Shikai Yu 《Cardiovascular Innovations and Applications》 2021年第3期33-44,共12页
Objective:To provide information on clinical characteristics and different durations of COVID-19 and to identify the potential risk factors for longer hospitalization of patients with COVID-19.Methods:In this retrospe... Objective:To provide information on clinical characteristics and different durations of COVID-19 and to identify the potential risk factors for longer hospitalization of patients with COVID-19.Methods:In this retrospective study,we enrolled 77 patients(age 52±20 years;44.2%males)with laboratory-confi rmed COVID-19 admitted to Beijing YouAn Hospital between January 21 and February 8,2020.Epidemiological,clinical,and radiological data on admission were collected;complications and outcomes were followed up until February 26,2020.The end point of the study was discharge alive within 2 weeks.Cox proportional-hazards regression was performed to identify risk factors for longer hospitalization.Results:Of 77 patients,there were 34 males(44.2%),24(31.2%)with comorbidities,22(28.6%)with lymphopenia,20(26.0%)with severe COVID-19,and 28(36.4%)with complications.By the end of follow-up,64 patients(83.1%)were discharged home,eight remained in hospital,and fi ve had died.Thirty-six patients(46.8%)were discharged within 14 days and thus reached the study end point,including 34 of the 57 patients with nonsevere COVID-19(59.6%)and two of the 20 patients with severe COVID-19(10%).The overall cumulative probability of the end point was 48.3%.Hospital length of stay and the duration from exposure to discharge for the 64 discharged patients were 13(10-16.5)days and 23(18-24.5)days,respectively.A multivariable stepwise Cox regression model showed that bilateral pneumonia on CT scan,shorter time from illness onset to admission,severity of disease,and lymphopenia were independently associated with longer hospitalization.Conclusions:COVID-19 has a shorter duration of disease and hospital length of stay than severe acute respiratory syndrome.Bilateral pneumonia on CT scan,shorter period from illness onset to admission,lymphopenia,and severity of disease are the risk factors for longer hospitalization of patients with COVID-19. 展开更多
关键词 COVID-19 SARS-CoV-2 Duration of disease
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Influence of Input Pulse Durations on Properties of Er^(3+)/Yb^(3+) Co-doped DCFA
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作者 ZHAN Sheng-bao ZHAO Shang-hong SHI Lei XU Jie ZHAO Xiao-ming 《Semiconductor Photonics and Technology》 CAS 2006年第3期205-210,共6页
Based on propagation-rate equations, the influence of different input pulse durations on the properties of Er^3+/Yb^3+ co-doped double-clad fiber amplifier at dynamic equilibrium was analyzed. The change characteris... Based on propagation-rate equations, the influence of different input pulse durations on the properties of Er^3+/Yb^3+ co-doped double-clad fiber amplifier at dynamic equilibrium was analyzed. The change characteristic of output power sag with pulse duration and repetition rate was shown. Whether single or multichannel input pulses are amplified, the shorter the input pulse duration is, the smaller the power sags of output pulse will be. At low repetition rate, upper gain values(Gupper) of gain swing are almost the same for different input pulse durations, which tend to the small signal gain, but lower gain value(Glower) of short input pulse is larger than that of long input pulse. At highrepetition rate, lower gain value(Glower) approaches to upper gain value(Glower). 展开更多
关键词 Er^3+/Yb^3+ co-doped Double-clad fiber amplifier Pulse duration Pulse repetition rate
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The Relationship between Global Solar Radiation and Sunshine Durations in Cameroon
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作者 R. Mbiaké A. Beya Wakata +5 位作者 E. Mfoumou E. Ndjeuna L. Fotso E. Tiekwe J. R. Kaze Djamen C. Bobda 《Open Journal of Air Pollution》 2018年第2期107-119,共13页
Based on the well-known modified Angstrom formula on the relationship between the sunshine duration and the global solar radiation, this paper aimed to estimate the value of the constant a and b in Cameroon. Only five... Based on the well-known modified Angstrom formula on the relationship between the sunshine duration and the global solar radiation, this paper aimed to estimate the value of the constant a and b in Cameroon. Only five cities (Maroua, Garoua, NGaoundéré, Yaoundé and Douala) had the both available in-situ data recorded during the period of eleven years (1996-2006) beside which four others cities (Dschang, Koundja, Yoko and Manfé) had only the in-situ sunshine duration available data recorded during the period of twenty years (1986-2006). The 9 cities were grouped in 3 different climate regions. Based on the data of the 5 first cities belonging the 3 regions, the follow constant values a1 = -0.05, a2 = -0.02, a3 = -0.14 and b1 = 0.94, b2 = 0.74, b3 = 1.12 were obtained. The Root Mean Square Error (RMSE) Mean Bias Error (MBE) and correlation coefficient (r) were also determined. Then we used these values to estimate the global solar radiation for the other four remain cities. The constants a and b obtained values are in accordance with those of the West Africa region which Cameroon belongs to. So they can be employed in estimating global solar radiation of location in Cameroon paying attention only to the geographical location information. 展开更多
关键词 Solar Radiation SUNSHINE DURATION ANGSTROM CONSTANTS CLIMATIC Region
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Selection of Suitable Features for Modeling the Durations of Syllables
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作者 Krothapalli S. Rao Shashidhar G. Koolagudi 《Journal of Software Engineering and Applications》 2010年第12期1107-1117,共11页
Acoustic analysis and synthesis experiments have shown that duration and intonation patterns are the two most important prosodic features responsible for the quality of synthesized speech. In this paper a set of featu... Acoustic analysis and synthesis experiments have shown that duration and intonation patterns are the two most important prosodic features responsible for the quality of synthesized speech. In this paper a set of features are proposed which will influence the duration patterns of the sequence of the sound units. These features are derived from the results of the duration analysis. Duration analysis provides a rough estimate of features, which affect the duration patterns of the sequence of the sound units. But, the prediction of durations from these features using either linear models or with a fixed rulebase is not accurate. From the analysis it is observed that there exists a gross trend in durations of syllables with respect to syllable position in the phrase, syllable position in the word, word position in the phrase, syllable identity and the context of the syllable (preceding and the following syllables). These features can be further used to predict the durations of the syllables more accurately by exploring various nonlinear models. For analying the durations of sound units, broadcast news data in Telugu is used as the speech corpus. The prediction accuracy of the duration models developed using rulebases and neural networks is evaluated using the objective measures such as percentage of syllables predicted within the specified deviation, average prediction error (μ), standard deviation (σ) and correlation coefficient (γ). 展开更多
关键词 PROSODY SYLLABLE DURATION SYLLABLE Position SYLLABLE Context SYLLABLE IDENTITY FEED Forward Neural Network
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Association of accelerometer-measured sleep duration and different intensities of physical activity with incident type 2 diabetes in a population-based cohort study 被引量:2
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作者 Xinyi Jin Yilin Chen +8 位作者 Hongliang Feng Mingqing Zhou Joey W.Y.Chang Yaping Liu Alice Pik Shan Kong Xiao Tan Yun-Kwok Wing Yannis Yan Liang Jihui Zhang 《Journal of Sport and Health Science》 SCIE CAS CSCD 2024年第2期222-232,共11页
Purpose:The aim of the current study was to investigate the association of accelerometer-measured sleep duration and different intensities of physical activity(PA)with the risk of incident type 2 diabetes in a populat... Purpose:The aim of the current study was to investigate the association of accelerometer-measured sleep duration and different intensities of physical activity(PA)with the risk of incident type 2 diabetes in a population-based prospective cohort study.Methods:Altogether,88,000 participants(mean age=62.2±7.9 years,mean±SD)were included from the UK Biobank.Sleep duration(short:<6 h/day;normal:6-8 h/day;long:>8 h/day)and PA of different intensities were measured using a wrist-won accelerometer over a 7-day period between 2013 and 2015.PA was classified according to the median or World Health Organization-recommendation:total volume of PA(high,low),moderate-to-vigorous PA(MVPA)(recommended,not recommended),and light-intensity PA(high,low).Incidence of type 2diabetes was ascertained using hospital records or death registries.Results:During a median follow-up of 7.0 years,1615 incident type 2 diabetes cases were documented.Compared with normal sleep duration,short(hazard ratio(HR)=1.21,95%confidence interval(95%CI):1.03-1.41)but not long sleep duration(HR=1.01,95%CI:0.89-1.15)was associated with excessive type 2 diabetes risk.This increased risk among short sleepers seems to be protected against by PA.Compared with normal sleepers with high or recommended PA,short sleepers with low volume of PA(HR=1.81,95%CI:1.46-2.25),not recommended(below the World Health Organization-recommended level of)MVPA(HR=1.92,95%CI:1.55-2.36),or low light-intensity PA(HR=1.49,95%CI:1.13-1.90)had a higher risk of type 2 diabetes,while short sleepers with a high volume of PA(HR=1.14,95%CI:0.88-1.49),recommended MVPA(HR=1.02,95%CI:0.71-1.48),or high light-intensity PA(HR=1.14,95%CI:0.92-1.41)did not.Conclusion:Accelerometer-measured short but not long sleep duration was associated with a higher risk of incident type 2 diabetes.A higher level of PA,regardless of intensity,potentially ameliorates this excessive risk. 展开更多
关键词 Light physical activity Sleep duration Triaxial accelerometer Type 2 diabetes UK Biobank
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Left bundle branch pacing vs biventricular pacing in heart failure patients with left bundle branch block:A systematic review and meta-analysis 被引量:2
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作者 Farah Yasmin Abdul Moeed +7 位作者 Rohan Kumar Ochani Hamna Raheel Malik Ali Ehtsham Awan Ayesha Liaquat Arisha Saleem Muhammad Aamir Nael Hawwa Salim Surani 《World Journal of Cardiology》 2024年第1期40-48,共9页
BACKGROUND Left bundle branch pacing(LBBP)is a novel pacing modality of cardiac resynchronization therapy(CRT)that achieves more physiologic native ventricular activation than biventricular pacing(BiVP).AIM To explore... BACKGROUND Left bundle branch pacing(LBBP)is a novel pacing modality of cardiac resynchronization therapy(CRT)that achieves more physiologic native ventricular activation than biventricular pacing(BiVP).AIM To explore the validity of electromechanical resynchronization,clinical and echocardiographic response of LBBP-CRT.METHODS Systematic review and Meta-analysis were conducted in accordance with the standard guidelines as mentioned in detail in the methodology section.RESULTS In our analysis,the success rate of LBBP-CRT was determined to be 91.1%.LBBP CRT significantly shortened QRS duration,with significant improvement in echocardiographic parameters,including left ventricular ejection fraction,left ventricular end-diastolic diameter and left ventricular end-systolic diameter in comparison with BiVP-CRT.CONCLUSION A significant reduction in New York Heart Association class and B-type natriuretic peptide levels was also observed in the LBBP-CRT group vs BiVP-CRT group.Lastly,the LBBP-CRT cohort had a reduced pacing threshold at follow-up as compared to BiVP-CRT. 展开更多
关键词 Left bundle branch pacing Biventricular pacing QRS duration Left ventricular ejection fraction Heart failure
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Spatiotemporal changes of gross primary productivity and its response to drought in the Mongolian Plateau under climate change 被引量:1
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作者 ZHAO Xuqin LUO Min +3 位作者 MENG Fanhao SA Chula BAO Shanhu BAO Yuhai 《Journal of Arid Land》 SCIE CSCD 2024年第1期46-70,共25页
Gross primary productivity(GPP)of vegetation is an important constituent of the terrestrial carbon sinks and is significantly influenced by drought.Understanding the impact of droughts on different types of vegetation... Gross primary productivity(GPP)of vegetation is an important constituent of the terrestrial carbon sinks and is significantly influenced by drought.Understanding the impact of droughts on different types of vegetation GPP provides insight into the spatiotemporal variation of terrestrial carbon sinks,aiding efforts to mitigate the detrimental effects of climate change.In this study,we utilized the precipitation and temperature data from the Climatic Research Unit,the standardized precipitation evapotranspiration index(SPEI),the standardized precipitation index(SPI),and the simulated vegetation GPP using the eddy covariance-light use efficiency(EC-LUE)model to analyze the spatiotemporal change of GPP and its response to different drought indices in the Mongolian Plateau during 1982-2018.The main findings indicated that vegetation GPP decreased in 50.53% of the plateau,mainly in its northern and northeastern parts,while it increased in the remaining 49.47%area.Specifically,meadow steppe(78.92%)and deciduous forest(79.46%)witnessed a significant decrease in vegetation GPP,while alpine steppe(75.08%),cropland(76.27%),and sandy vegetation(87.88%)recovered well.Warming aridification areas accounted for 71.39% of the affected areas,while 28.53% of the areas underwent severe aridification,mainly located in the south and central regions.Notably,the warming aridification areas of desert steppe(92.68%)and sandy vegetation(90.24%)were significant.Climate warming was found to amplify the sensitivity of coniferous forest,deciduous forest,meadow steppe,and alpine steppe GPP to drought.Additionally,the drought sensitivity of vegetation GPP in the Mongolian Plateau gradually decreased as altitude increased.The cumulative effect of drought on vegetation GPP persisted for 3.00-8.00 months.The findings of this study will improve the understanding of how drought influences vegetation in arid and semi-arid areas. 展开更多
关键词 gross primary productivity(GPP) climate change warming aridification areas drought sensitivity cumulative effect duration(CED) Mongolian Plateau
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Spatiotemporal changes in sunshine duration and its influential factors in Chongqing,China from 1961 to 2020
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作者 LI Jun XIA Hongxuan +3 位作者 JIANG Jinge XU Weifeng WEN Di XU Junfeng 《Journal of Mountain Science》 SCIE CSCD 2024年第6期2005-2024,共20页
The surface solar radiation in most parts of the world has undergone a phenomenon known as global dimming and brightening,characterized by an initial decrease followed by an increase.As a result,the sunshine duration(... The surface solar radiation in most parts of the world has undergone a phenomenon known as global dimming and brightening,characterized by an initial decrease followed by an increase.As a result,the sunshine duration(SD)has decreased in the past 60 years.Against the backdrop of global dimming and brightening,SD has decreased to varying degrees in many regions of China.Using the observed data of SD,cloud amount(total cloud amount and low cloud amount,abbreviated as TCA and LCA),precipitation,and relative humidity(RH)from 34 meteorological stations in Chongqing during the period of 1961-2020,along with a digital elevation model(DEM)with a resolution of 90 m,this study analyzed the spatiotemporal variations and influencing factors of SD.The analysis employed methods such as linear regression,Mann-Kendall test,wavelet transformation,and DEM-based possible SD distributed model.The results showed that the annual SD in Chongqing has significantly decreased over the last 60 years,with a decreasing interannual trend rate(ITR)of 40.4 h/10a.Except for no obvious trend in spring,SD decreased significantly in summer,autumn and winter at the ITR of 21.1 h/10a,8.5 h/10a and 7.5 h/10a,respectively.An abrupt decrease in the annual SD was found in 1979.The difference before and after the abrupt decrease was 177.7 h.The difference before and after the abrupt decrease was 177.7 h.The annual SD possessed the oscillation period of 11a.The spatial heterogeneity of the mean annual SD during the last 60 years was obvious.The distribution of SD in Chongqing is high in the northeast and low in the southeast.In addition,about 73%of the total area in Chongqing showed a significant and very significant decreasing trend.The regions with significant changes are mainly concentrated in the regions with altitudes of 200~1000 m.The increasing LCA was the main cause of the decrease of the annual SD in the regions with 200-400 m altitude decreased the most and changed the most.Increasing LCA is the primary cause of the reduction in annual SD,showing a strong negative correlation coefficient of-0.7292.In Chongqing,PM2.5 concentration showed a significant decrease trend in annual,spring,autumn and winter during 2000-2020,but the significant correlation between PM2.5 concentration and SD was only in autumn and reached an extremely significant level. 展开更多
关键词 Sunshine duration Spatiotemporal changes Mann-Kendall test Wavelet analysis Geodetector model
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Spatiotemporal Characteristics of Rainfall over Different Terrain Features in the Middle Reaches of the Yangtze River Basin during the Warm Seasons of 2016–20
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作者 Qian WEI Jianhua SUN +2 位作者 Shenming FU Yuanchun ZHANG Xiaofang WANG 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2024年第5期915-936,共22页
Based on hourly rain gauge data during May–September of 2016–20,we analyze the spatiotemporal distributions of total rainfall(TR)and short-duration heavy rainfall(SDHR;hourly rainfall≥20 mm)and their diurnal variat... Based on hourly rain gauge data during May–September of 2016–20,we analyze the spatiotemporal distributions of total rainfall(TR)and short-duration heavy rainfall(SDHR;hourly rainfall≥20 mm)and their diurnal variations over the middle reaches of the Yangtze River basin.For all three types of terrain(i.e.,mountain,foothill,and plain),the amount of TR and SDHR both maximize in June/July,and the contribution of SDHR to TR(CST)peaks in August(amount:23%;frequency:1.74%).Foothill rainfall is characterized by a high TR amount and a high CST(in amount);mountain rainfall is characterized by a high TR frequency but a small CST(in amount);and plain rainfall shows a low TR amount and frequency,but a high CST(in amount).Overall,stations with high TR(amount and frequency)are mainly located over the mountains and in the foothills,while those with high SDHR(amount and frequency)are mainly concentrated in the foothills and plains close to mountainous areas.For all three types of terrain,the diurnal variations of both TR and SDHR exhibit a double peak(weak early morning and strong late afternoon)and a phase shift from the early-morning peak to the late-afternoon peak from May to August.Around the late-afternoon peak,the amount of TR and SDHR in the foothills is larger than over the mountains and plains.The TR intensity in the foothills increases significantly from midnight to afternoon,suggesting that thermal instability may play an important role in this process. 展开更多
关键词 short duration heavy rainfall diurnal variation foothill rainfall
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Dynamic Forecasting of Traffic Event Duration in Istanbul:A Classification Approach with Real-Time Data Integration
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作者 Mesut Ulu Yusuf Sait Türkan +2 位作者 Kenan Menguc Ersin Namlı Tarık Kucukdeniz 《Computers, Materials & Continua》 SCIE EI 2024年第8期2259-2281,共23页
Today,urban traffic,growing populations,and dense transportation networks are contributing to an increase in traffic incidents.These incidents include traffic accidents,vehicle breakdowns,fires,and traffic disputes,re... Today,urban traffic,growing populations,and dense transportation networks are contributing to an increase in traffic incidents.These incidents include traffic accidents,vehicle breakdowns,fires,and traffic disputes,resulting in long waiting times,high carbon emissions,and other undesirable situations.It is vital to estimate incident response times quickly and accurately after traffic incidents occur for the success of incident-related planning and response activities.This study presents a model for forecasting the traffic incident duration of traffic events with high precision.The proposed model goes through a 4-stage process using various features to predict the duration of four different traffic events and presents a feature reduction approach to enable real-time data collection and prediction.In the first stage,the dataset consisting of 24,431 data points and 75 variables is prepared by data collection,merging,missing data processing and data cleaning.In the second stage,models such as Decision Trees(DT),K-Nearest Neighbour(KNN),Random Forest(RF)and Support Vector Machines(SVM)are used and hyperparameter optimisation is performed with GridSearchCV.In the third stage,feature selection and reduction are performed and real-time data are used.In the last stage,model performance with 14 variables is evaluated with metrics such as accuracy,precision,recall,F1-score,MCC,confusion matrix and SHAP.The RF model outperforms other models with an accuracy of 98.5%.The study’s prediction results demonstrate that the proposed dynamic prediction model can achieve a high level of success. 展开更多
关键词 Traffic event duration forecasting machine learning feature reduction shapley additive explanations(SHAP)
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Contributors to tidal duration asymmetry with varied coastline configurations on western shelf of Yellow Sea
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作者 Xi Feng Zheng Li +3 位作者 Hui Feng Jia-yan Yang Shou-peng Xie Wei-bing Feng 《Water Science and Engineering》 EI CAS CSCD 2024年第1期1-12,共12页
Coastal management in China is confronted with an urgent choice between natural restoration and maintenance of existing seawalls and reclaimed land for economic development.A key criterion for making this decision is ... Coastal management in China is confronted with an urgent choice between natural restoration and maintenance of existing seawalls and reclaimed land for economic development.A key criterion for making this decision is the resilience to coastal flooding,which depends on the ability to predict tidal level.Tidal duration asymmetry(TDA)is a key parameter in determination of the arrival and duration of flood tides.This study selected the western inner shelf of the Yellow Sea(WYS)as the study area and investigated the responses of TDA to different shoreline configurations and relative sea level rise.The responses of TDA to shoreline reconstruction yielded spatial variability locally and remotely.In the nearshore area,the responses of TDA to the complex ocean environment mainly originated from the combined functions of reflection,bottom friction,and advection,which controlled the energy transfer from M2 or S2 constituents to their overtides or compound tides.The sensitivity of TDA to coastline typologies was not limited to coastal waters but could stretch over the entire inner shelf.The vulnerability of tidal responses was due to the displacement of the M2 amphidrome of the Kelvin wave on the WYS,which in turn changed tidal energy fluxes over the regime.The relative sea level rise could intensify the feedback of TDA to seawalls and land reclamation. 展开更多
关键词 Tidal duration asymmetry Western inner shelf of Yellow Sea Natural restoration Relative sea level rise Tidal amphidrome
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Enabling low-cost decentralized power reserves adopting carbon dioxide for green methane exchange in stabilized clathrate adsorbent
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作者 Lucas Hanssens Maarten Houlleberghs +7 位作者 C.Vinod Chandran Geert Watson Sambhu Radhakrishnan Pascal Van Der Voort Joeri F.M.Denayer Christine E.A.Kirschhock Johan A.Martens Eric Breynaert 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第10期438-443,I0009,共7页
1.Challenges circular methane energy systems In recent decades,methane-based energy systems have rapidly gained traction across the globe because of the increasing availability of low-cost methane production capacity.... 1.Challenges circular methane energy systems In recent decades,methane-based energy systems have rapidly gained traction across the globe because of the increasing availability of low-cost methane production capacity.However,fossil methane production and combustion lead to large greenhouse gas emissions,contributing to climate change[1]. 展开更多
关键词 Long duration energy storage Green methane Carbon neutrality Confined clathrate hydrates CH_(4)/CO_(2) exchange Direct gas exchange
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Relations of intensity just noticeable difference to intensity of tonal bursts with various durations 被引量:1
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作者 LONG Zhangcai TANG Chaoqun (Department of Physics, Huazhong University of Science & Technology Wuhan 430074) YAO Qiuping (Hubei Provincial Institute of Measurement and Test Wuhan 430071) 《Chinese Journal of Acoustics》 2000年第2期114-122,共9页
The relations of intensity Just Noticeable Difference (JND) to intensity for tone bursts maybe,depend on signal durations according to Jont B.Allen's [J. Acoust. Soc. Am. 102 3, 1997, 3628--3646.]. The intensity j... The relations of intensity Just Noticeable Difference (JND) to intensity for tone bursts maybe,depend on signal durations according to Jont B.Allen's [J. Acoust. Soc. Am. 102 3, 1997, 3628--3646.]. The intensity just noticeable differences for tone bursts with durations of 1 ms, 10 ms, 100 ms, 1000 ms, 5000 ms and 10000 ms were measured at different intensity levels of 20 dB, 30 dB, 40 dB, 50 dB, 60 dB, 70 dB, 80 dB, 90 dB, 100 dB. The data show that variance of Weber fraction (△I/I) with intensity is distinct from Riesz's result and SPIN theory, and that the relations between Weber fraction and intensity for signals of different durations are similar in spite of Weber fraction decreasing to asymptote with signal duration increasing. This means the difference of pulse measurement of intensity JND from Riesz's result and SPIN theory does not arise from the limited signal duration of pulse method and provides new cue for hearing research. 展开更多
关键词 JND Relations of intensity just noticeable difference to intensity of tonal bursts with various durations
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Predictors of permanent pacemaker implantation following transcatheter aortic valve replacement-the search is still on!
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作者 Sudesh Prajapathi Akshyaya Pradhan 《World Journal of Cardiology》 2024年第3期104-108,共5页
Several anatomical,demographic,clinical,electrocardiographic,procedural,and valve-related variables can be used to predict the probability of developing con-duction abnormalities after transcatheter aortic valve repla... Several anatomical,demographic,clinical,electrocardiographic,procedural,and valve-related variables can be used to predict the probability of developing con-duction abnormalities after transcatheter aortic valve replacement(TAVR)that necessitate permanent pacemaker(PPM)implantation.These variables include calcifications around the device landing zone and in the mitral annulus;pre-existing electrocardiographic abnormalities such as left and right bundle branch blocks(BBB),first-and second-degree atrioventricular blocks,as well as bifas-cicular and trifascicular blocks;male sex;diabetes mellitus(DM);hypertension;history of atrial fibrillation;renal failure;dementia;and use of self-expanding valves.The current study supports existing literature by demonstrating that type 2 DM and baseline right BBB are significant predictors of PPM implantation post-TAVR.Regardless of the side of the BBB,this study demonstrated,for the first time,a linear association between the incidence of PPM implantation post-TAVR and every 20 ms increase in baseline QRS duration(above 100 ms).After a 1-year follow-up,patients who received PPM post-TAVR had a higher rate of hospital-ization for heart failure and nonfatal myocardial infarction. 展开更多
关键词 Bundle branch block Self expanding aortic valve Atrioventricular node Diabetes mellitus QRS duration
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