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Correlation between current intensity and effective duration in the treatment of botulinus toxin for cerebral palsy by myoelectricity locating
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作者 Jianjun Liu Shurong Ji Yingyuan Hu Yanchun Li Weihong Wu Huabao Lu Yan Zhang 《Neural Regeneration Research》 SCIE CAS CSCD 2006年第4期361-363,共3页
BACKGROUND: Researches prove that the treatment of cerebral palsy by botulinus toxin (BTX-A) can improve effect and prolong effective duration. Current intensity is the important factor during injection. OBJECTIVE... BACKGROUND: Researches prove that the treatment of cerebral palsy by botulinus toxin (BTX-A) can improve effect and prolong effective duration. Current intensity is the important factor during injection. OBJECTIVE: To observe the changes of motor function and muscular intensity of children with spastic cerebral palsy after injecting BTX-A and analyze correlation between current intensity and effective duration. DESIGN: Cases control trial before and after nerves block SETTING: Capital University of Medical Sciences, China Rehabilitation Research Center PARTICIPANTS: From June 2002 to November 2004, 14 children with spastic cerebral palsy were treated by BTX-A block. All children were hospitalized in the Children Rehabilitation Department of China Rehabilitation Research Center. The children included 9 male and 5 female, and ranged from 4 to 13 years old, and average age was (6±2) years. Muscular tension ranged from grade 1 to grade 3. The diagnosis and the tape of cerebral palsy based on standard of the Fist Nationwide Cerebral Palsy Symposium, and all children were diagnosed with electroencephalogram (EEG), CT and MRI, and permitted by their guardians. METHODS: (1) Locating and calculation: To locate block points by G6805-2A electro-therapeutic apparatus (Shanghai Huayi Electronic Instrument Plant) at the least stimulating current (continuous wave; impulse frequency; 2.667-83.333 Hz; current intensity: 0-6 mA; voltage: 6 V) to touch off muscles contraction. The current intensity of each point was recorded, and the average current intensity of each patient was calculated at the same time. (2) Dose of BTX-A: Basing upon the spastic degree and weight of patients, the dose was made certain: dose (IU)=(scores of Modified Ashworth Scale +2.5) xweight (kg). The number of the block points was in all 4. The dose of injection ranged from 50 IU to 160 IU with the average of (73.6+25.8) IU. The BTX-A was made by Lanzhou Institute of Biological Products, and each bottle contains 100 IU BTX-A. Muscular tension was evaluated by Modified Ashworth Scale. The scale ranged from grade 0 to grade 4, and the scores were from 0 to 4. The higher the scores were, the higher the muscular tension was. (3) Effect: Changes of muscular tension were evaluated by modified Ashworth Scale before and after block. Motor function was evaluated by Physician Rating Scale (PRS) before and after treatment. It contained Gait pattern, Hindfoot (ankle) position (stance-floor contact), Hindfoot position (foot strike), Knee position (degree of recurvation), Crouch and Speed of gait. The scores ranged from 0 to 14. The higher the points were, the better the motor function was. (4) Effective duration: The duration was definited by the recovering of the Modified Ashworth Scale. (5) Statistic analysis: Firstly, the current intensity and the effect duration were analyzed by One-Sample Kolmogorov-Smirnov Test, the current intensity: Z= 0.456, P= 0.985, the effective duration: Z= 0.557, P= 0.915. Both data were normal distribution. Secondly, both data were analyzed by Linear Regression. The efficiency of the BTX-A block was analyzed by paired-samples t test. MAIN OUTCOME MEASURES: (1) Changes of motor function of muscular tension; (2) correlation between current intensity and effective duration. RESULTS: Fourteen children with spastic cerebral palsy were all involved in the final analysis. (1) Therapeutic effect: The average score of Ashworth scale after block was lower than that before block [(1.02±0.34) points vs. (2.12±0.48) points, t= 3.644, P〈 0.01]. The average score of RPS after block was higherthan that before block [(9.75±2.78) points vs. (6.16±0.58) points, t =13.222, P〈 0.01]. (2) Relation between the current intensity and the effective duration: The current intensity was (0.1857±0.0506) mA, and the effective duration was (26.36±4.48) weeks. The current intensity was negative correlation with effective duration (r = -0.775, P = 0.01 ). CONCLUSION: (1) BTX-A occlusion can decrease muscular tension and improve motor function of lower limbs of children with spastic cerebral palsy. (2) The lower the current intensity is, the longer the effective duration is. 展开更多
关键词 Correlation between current intensity and effective duration in the treatment of botulinus toxin for cerebral palsy by myoelectricity locating BTX
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Changing Features of Sunshine Duration and Effects on Greenhouse Production in Shouguang City 被引量:1
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作者 Wang Xiaoli Yan Fengjun +3 位作者 Wang Tianru Xu Tai an Lu Dan Zhang Xiuzhen 《Meteorological and Environmental Research》 CAS 2016年第6期72-75,共4页
Based on data of monthly sunshine duration in Shouguang City during 1961-2013,changing features of sunshine duration and effects on greenhouse production in Shouguang City were analyzed by using linear tendency method... Based on data of monthly sunshine duration in Shouguang City during 1961-2013,changing features of sunshine duration and effects on greenhouse production in Shouguang City were analyzed by using linear tendency method,M-K mutation test and Molet wavelet analysis. The results show that in Shouguang City,sunshine duration in a year and each season reduced obviously from 1961 to 2013,and sunshine duration in a year and autumn changed suddenly in the 1990s,while sunshine duration in winter and spring changed suddenly in the 1980s. There existed obvious periodic variations of sunshine duration in a year and various seasons from 1961 to 2013. The reduction of sunshine duration and the increase of cloudy days resulted in the decrease in the yield of crops in solar greenhouses,so some effective measures should be taken to enhance the light intensity and time in solar greenhouses to promote crop growth. 展开更多
关键词 Changes of SUNSHINE duration SOLAR GREENHOUSES Production effectS China
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Mining Applicable Elite Alleles of Growth Duration, Plant Height and Panicle Number per Plant by Conditional QTL Mapping in Japonica Rice 被引量:2
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作者 Jian-hua JIANG Qi-bing ZHAO +4 位作者 Qiang-ming LIU Lan CHEN Fu-long CHEN Bao-jian QIAO De-lin HONG 《Rice science》 SCIE 2011年第3期196-203,共8页
Unconditional and conditional QTL mapping were conducted for growth duration (GD), plant height (PH) and effective panicle number per plant (PN) using a recombinant inbred line (RIL) population derived from a cross be... Unconditional and conditional QTL mapping were conducted for growth duration (GD), plant height (PH) and effective panicle number per plant (PN) using a recombinant inbred line (RIL) population derived from a cross between two japonica rice varieties Xiushui 79 and C Bao. The RIL population consisted of 254 lines was planted in two environments, Nanjing and Sihong, Jiangsu Province, China. Results showed that additive effects were major in all of QTLs for GD, PH and PN detected by the two methods, and the epistatic effects explained a small proportion of phenotypic variation. No interactions were detected between additive QTL and environment, and between epistatic QTL pairs and environment. After growth duration was adjusted to an identical level, RM80-160bp was detected as an applicable elite allele for PN, with an additive effect of 0.71. When effective panicle number per plant was adjusted to an identical level, RM448-240bp was detected as an applicable elite allele for GD, with an additive effect of 4.64. After plant height was adjusted to an identical level, RM80-160bp was detected as an applicable elite allele for PN, with an additive effect of 0.62, and RM448-240bp was detected as an applicable elite allele for GD, with an additive effect of 3.89. These applicable elite alleles could be used to improve target traits without influencing the other two traits. 展开更多
关键词 japonica rice growth duration plant height effective panicle number per plant unconditional QTL mapping conditional QTL mapping recombinant inbred line
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Determination and application of path duration of seismic ground motions based on the K-NET data in Sagami Bay,Japan
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作者 Shiyang Chen Xiaojun Li +1 位作者 Lei Fu Su Chen 《Earthquake Science》 2022年第4期263-279,共17页
Duration models are one of the important parameters in ground-motion simulations.This model varies in different study areas,and plays a critical role in nonlinear structural response analysis.Currently,available empir... Duration models are one of the important parameters in ground-motion simulations.This model varies in different study areas,and plays a critical role in nonlinear structural response analysis.Currently,available empirical models are being globally used in ground-motion simulations,with limited research focusing on path duration in specific regions.In this study,we collected 6,486 sets of three-component strong-motion records from 29 K-NET stations in the Sagami Bay,Japan,and its surrounding areas between January 2000 to October 2018.We extracted the effective duration of 386 pieces of ground-motion records by manually picking up the S-wave arrival time and calculating the significant duration.We then obtained the path duration model of the study area based on the empirical equation of dynamic corner frequency and source duration of Boore(2009).Compared with the results of the available empirical models,the Fourier spectrum of the simulated ground motion from our effective duration model showed higher accuracy in the long-term range,with less fitting residuals.This path duration model was then applied to simulate two earthquakes of M_(W)5.4 and M_(W)6.2,respectively,in the region using the stochastic finite-fault method with a set of reliable source,path,and site parameters determined for the study area.The simulation results of most stations fit well with observation records in the 0-30 Hz frequency band.For the M_(W)5.4 earthquake,the simulated ground motions at KNG005/KNG010/SZO008 stations were relatively weak in the mid to high frequency band(1-30 Hz)because the quality factor and geometric diffusion model used in the simulation were the averages of the entire Sagami Bay region,causing a bias in the results of a few stations owing to local crustal velocity anomalies and topographic effects.For the M_(W)6.2 earthquake,the simulated ground motions were relatively weak at all SZO and TKY stations,mainly because of the close distance from these stations to the epicenter and the complex seismic-wave propagation paths.The analysis suggests that the differences between the simulation results of the two earthquakes were mainly related to complex geological conditions and seismic-wave propagation paths. 展开更多
关键词 Sagami Bay path duration effective duration stochastic finite-fault method
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Comparison of the treatment duration and nursing requirements of the EarWell infant ear correction system for different types of auricle deformities
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作者 Wei Wei Chang-Zhi Sun +4 位作者 Xiao-Ya Wang Jie Zhong Qian-Jun Liao Yan-Ying Cai Rui Mi 《Frontiers of Nursing》 2023年第3期357-362,共6页
Objective:To observe whether the Ear Well infant ear correction system makes any difference in terms of the treatment effect,duration,complication rate,and nursing care requirements in different types of infant auricl... Objective:To observe whether the Ear Well infant ear correction system makes any difference in terms of the treatment effect,duration,complication rate,and nursing care requirements in different types of infant auricle deformities.Methods:A total of 93 infant patients with auricular deformity(age:<3 months of age)who were diagnosed and treated in Guangzhou Children and Women’s Medical Center from April 2018 to September 2020 were selected and treated with the Ear Well infant ear correction system.We observed and recorded the effects of the Ear Well infant ear correction system,the treatment duration,the number of rebound cases,and complications that are likely to occur during treatment,and noted the related factors causing complications and the relative requirements for nursing care.Results:The Earwell infant ear correction system could effectively correct infant auricle deformities.Among the 93 cases,90 cases had positive therapeutical outcome and the effective rate was 96.77%.The treatment duration for lop ear and protruding ear was longer than for other auricle deformities;the deformity recoil and the treatment compilation rates were much higher for these 2 deformity types,and the difference was statistically significant(P<0.05).Conclusions:The treatment suggestion for the wearing duration of the Ear Well infant ear correction system for lop ear and protruding ear is a prolonged duration compared with that for other infant auricle deformities.Fur ther,the requirements for nursing care intensity and infant patient’s guardian’s nursing knowledge and skill are obviously increased for these 2 types of auricle deformities. 展开更多
关键词 complication rate correction effect EarWell infant ear correction system infant auricle deformities nursing care and patient guardian education treatment duration
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Effects of hanging wall and footwall on demand of structural input energy during the 2008 Wenchuan earthquake 被引量:2
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作者 Lu Shunan Li Shuang +1 位作者 Zhai Changhai Xie Lili 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2013年第1期1-12,共12页
Systematic differences in the duration and frequency content of ground motions from the hanging wall and footwall during the 2008 Wenchuan earthquake are investigated,focusing on the influence of these differences on ... Systematic differences in the duration and frequency content of ground motions from the hanging wall and footwall during the 2008 Wenchuan earthquake are investigated,focusing on the influence of these differences on structural input energy based on the elastic and inelastic energy responses of structures.A comparison of the input energy spectra between the hanging wall and the footwall reveal that the structural input energy on the hanging wall is not amplified due to the short duration and low peak ground velocity to acceleration ratio(V/A).However,the larger demand of structural input energy on the footwall in the range of medium and long periods is observed and the demand increases up to 50% relative to the average level of structural input energy for rupture distances larger than 30 km.The importance of considering the footwall effect on structural input energy when comparing ground motions in the range of medium and long periods is recognized. 展开更多
关键词 Wenchuan earthquake duration frequency content hanging wall effect footwall effect input energy
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Analysis of effect factors-based stochastic network planning model 被引量:1
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作者 Chu Chunchao 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2008年第1期112-118,共7页
Looking at all the indeterminate factors as a whole and regarding activity durations as independent random variables, the traditional stochastic network planning models ignore the inevitable relationship and dependenc... Looking at all the indeterminate factors as a whole and regarding activity durations as independent random variables, the traditional stochastic network planning models ignore the inevitable relationship and dependence among activity durations when more than one activity is possibly affected by the same indeterminate factors. On this basis of analysis of indeterminate effect factors of durations, the effect factors-based stochastic network planning (EFBSNP) model is proposed, which emphasizes on the effects of not only logistic and organizational relationships, but also the dependent relationships, due to indeterminate factors among activity durations on the project period. By virtue of indeterminate factor analysis the model extracts and describes the quantitatively indeterminate effect factors, and then takes into account the indeterminate factors effect schedule by using the Monte Carlo simulation technique. The method is flexible enough to deal with effect factors and is coincident with practice. A software has been developed to simplify the model-based calculation, in VisualStudio.NET language. Finally, a case study is included to demonstrate the applicability of the proposed model and comparison is made with some advantages over the existing models. 展开更多
关键词 stochastic network planning ACTIVITY duration effect factor
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OBSERVATION ON THE TIME-EFFECT OF ACUPUNCTURE IN IMPROVING SMALL AIRWAY FUNCTION
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作者 陈友梅 张压西 孔立红 《World Journal of Acupuncture-Moxibustion》 1997年第2期26-28,共3页
Sixty-three patients with small airway obstruction were randomly divided into 3 groups treaded by acupuncture of 20 min, 40 min and 60 min. After acupuncture treatment, the function of the small airway in all patients... Sixty-three patients with small airway obstruction were randomly divided into 3 groups treaded by acupuncture of 20 min, 40 min and 60 min. After acupuncture treatment, the function of the small airway in all patients of the three groups improved significantly(P<0.001). Comparison in of multiple indexes among the three groups showed that the therapeutic effects of the 40 min-and 60 min-groups were distinctly superior to that of the 20 min-group (P < 0.005), while that of the 40 min- and 60 min-groups had no significant difference (P>0.05). It reveals that acupuncture can regulate the function of small airway of the lung and the therapeutic effect is relevant to the needling duration. 展开更多
关键词 AIRWAY RESISTANCE ACUPUNCTURE effect duration of ACUPUNCTURE
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Isolation, Identification and Earliness Effect Analysis of Rice Dominant Earliness Gene Ef-cd
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作者 DENG Xiao-jian WANG Ping-rong +2 位作者 LI Xiu-lan DONG Chun-lin YANG Zhi-rong 《Agricultural Sciences in China》 CAS CSCD 2005年第8期561-566,共6页
Ef-cd gene is a dominant earliness gene located on the short arm of rice chromosome 3. In this paper, through continuous backcross, self-pollination and molecular marker assisted selection, individual Ef-cd gene was i... Ef-cd gene is a dominant earliness gene located on the short arm of rice chromosome 3. In this paper, through continuous backcross, self-pollination and molecular marker assisted selection, individual Ef-cd gene was isolated and its nearly isogenic lines were constructed by using early-maturing indica line 6442S-7 as the donor parent, and by using latematuring indica line Minghui 63 (MH63), Shuhui 881 (SH881) and Shuhui 527 (SH527) as the recurrent parents (genetic background), respectively. Further, it was found out that Ef-cd gene could generally advance rice to head 11-14 d earlier. So, it was considered that Ef-cd gene played an important role in rapid developing early-maturing and super high-yielding rice varieties. 展开更多
关键词 RICE Growth duration EARLINESS Dominant earliness gene Gene effect
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Evaluation of Effects of Tea Saponin on Behavior, Growth and Development of Cylas formicarius (Coleoptera: Brentidae)
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作者 Rujun PAN Xiuhua TANG +1 位作者 Longfei HE Liyun REN 《Agricultural Biotechnology》 CAS 2019年第6期36-41,共6页
[Objectives] This study was conducted to expand the insect resistance spectrum of tea saponin, and its control effect on Cylas formicarius and the potential as an insecticide for pest control were explored. [Methods] ... [Objectives] This study was conducted to expand the insect resistance spectrum of tea saponin, and its control effect on Cylas formicarius and the potential as an insecticide for pest control were explored. [Methods] The olfactory avoidance rate of C. formicarius to tea saponin aqueous solution was determined by Y-type olfactometer;the feeding avoidance rate of C. formicarius to tea saponin was determined by the selective method;the antifeedant rate of C. formicarius to tea saponin was determined by non-selective method;and the development duration and mortality of C. formicarius under the influence of tea saponin were determined by artificial feeding method. [Results] C. formicarius had no significant olfactory tendency to every concentration of tea saponin, and the olfactory avoidance rate of 20.0% tea saponin aqueous solution was only 9.14%. Tea saponin had a feeding avoidance effect on C. formicarius, and the avoidance rate increased with the increase of tea saponin concentration. At 6 h, the feeding avoidance rates of 0.5%, 1.0%, 5.0%, 10.0% and 20.0% tea saponin on C. formicarius were 58.14%, 77.77%, 88.23%, 95.00% and 97.65 %, respectively;and the feeding avoidance effect at 6 h was significant, and the feeding avoidance rate was higher than that of 1 h. Tea saponin had a significant antifeedant effect on C. formicarius, and the longer the feeding time, the higher the antifeedant rate. At 72 h, the antifeedant rates of 0.5%, 1.0%, 5.0%, 10.0 % and 20.0% tea saponin to C. formicarius were 63.01%, 67.54%, 97.14 %, 96.42% and 98.57%, respectively. The larval development duration of C. formicarius was shortened with the increase of tea saponin concentration, and the larval death occurred. The development duration of larvae under the influence of 1.0% tea saponin was the shortest, which was 4.01 d shorter than that of the control, and the mortality was the highest, which was 26.65%. [Conclusions] Tea saponin had neither olfactory avoidance effect nor olfactory attracting effect to C. formicarius, but had obvious feeding avoidance effect and strong antifeedant effect. Tea saponin can shorten the development duration of the larvae of C. formicarius and cause the death of the larvae. 展开更多
关键词 Tea saponin Cylas formicarius Avoidance effect Antifeedant effect Artificial feeding method Developmental duration
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蒲元和胃胶囊联合雷贝拉唑治疗反流性食管炎的临床评价 被引量:1
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作者 闫莎莎 马雪瑶 +1 位作者 许园晨 张国瑜 《中国药物应用与监测》 CAS 2024年第4期468-471,共4页
目的 观察蒲元和胃胶囊联合雷贝拉唑治疗反流性食管炎的作用。方法 纳入河南大学第一附属医院胸外科2022年6月至2024年1月收治的102例反流性食管炎患者,以随机数字表法分成观察组(51例)与对照组(51例),给予对照组患者雷贝拉唑治疗,给予... 目的 观察蒲元和胃胶囊联合雷贝拉唑治疗反流性食管炎的作用。方法 纳入河南大学第一附属医院胸外科2022年6月至2024年1月收治的102例反流性食管炎患者,以随机数字表法分成观察组(51例)与对照组(51例),给予对照组患者雷贝拉唑治疗,给予观察组患者蒲元和胃胶囊联合雷贝拉唑治疗,对比2组临床疗效、上腹痛、反酸与嗳气症状缓解时间、治疗前后反流性疾病问卷(RDQ)评分及胃动素、胃泌素水平以及不良反应情况。结果 观察组总有效率(96.08%)比对照组(84.31%)更高(χ^(2)=3.991,P<0.05);观察组患者的上腹痛、反酸与嗳气症状缓解时间分别为(6.15±0.52) d、(5.80±0.52) d、(5.52±0.38) d,均分别短于对照组患者(8.44±0.73) d、(7.38±0.66) d、(6.72±0.82) d,t=18.247、13.429、9.482,P<0.001;观察组患者治疗后症状发作频率评分为(3.99±0.52)分,症状发作程度评分为(5.48±0.69)分,均短于对照组治疗后评分(6.24±0.67)分、(7.42±0.72)分,t=18.946、13.893,P<0.001;观察组患者治疗后胃动素、胃泌素水平分别为(331.29±4.92) ng·L^(-1)、(178.54±4.37) pg·m L^(-1),均高于对照组(299.54±5.23) ng·L^(-1)、(143.25±4.92) pg·m L^(-1),t=31.577,P<0.001;观察组(3.92%)与对照组不良反应率(5.88%)差异无统计学意义,χ^(2)=0.210,P>0.05。结论 蒲元和胃胶囊结合雷贝拉唑治疗反流性食管炎效果良好,患者症状缓解快,胃肠功能恢复良好,治疗不良反应较少,值得应用。 展开更多
关键词 反流性食管炎 蒲元和胃胶囊 雷贝拉唑 疗效 症状缓解时间 反流性疾病问卷 不良反应
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不同药剂对柞园栎凹翅萤叶甲防效初试
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作者 赵世文 赵鸿宇 +3 位作者 崔国杰 韩冰 穆秀奇 李喜升 《园艺与种苗》 CAS 2024年第8期81-82,86,共3页
[目的]有效降低栎凹翅萤叶甲危害,保证健康有序的柞蚕生产。[方法]采用试虫小区套袋药剂试验法,依据常规使用浓度,设置乐果50 mL、敌敌畏15 mL、敌克+敌克1号组合20 mL、蚕敌一扫光20 mL,各药剂兑水15 L配置成相应药剂溶液,以清水为对照... [目的]有效降低栎凹翅萤叶甲危害,保证健康有序的柞蚕生产。[方法]采用试虫小区套袋药剂试验法,依据常规使用浓度,设置乐果50 mL、敌敌畏15 mL、敌克+敌克1号组合20 mL、蚕敌一扫光20 mL,各药剂兑水15 L配置成相应药剂溶液,以清水为对照,进行药剂防效试验及持效期试验,24 h后调查试虫情况。[结果]蚕敌一扫光、敌敌畏、敌克+敌克1号对试虫防效较好,均可达85%以上,其中敌克+敌克1号防效达95%;持效期试验,敌克+敌克1号持效期3~5 d,其他药剂药后3 d防效均明显降低。[结论]敌克+敌克1号、蚕敌一扫光、敌敌畏对栎凹翅萤叶甲均有较好的防效,推荐有蚕柞园选用敌克+敌克1号,无蚕柞园选用蚕敌一扫光。 展开更多
关键词 药剂 栎凹翅萤叶甲 防效 持效期
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基于层次聚类分场景的光伏汇聚趋势量化方法
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作者 杨锡运 刘晗 +3 位作者 陈文进 彭琰 陈菁伟 王晨旭 《太阳能学报》 EI CAS CSCD 北大核心 2024年第3期496-505,共10页
持续功率曲线能反映长时间波动特性规律,通过研究已建设光伏集群持续功率曲线,建立预测模型揭示不同规模集群的汇聚演化规律,最终得到待建光伏集群的持续功率曲线。首先,利用层次聚类算法确定光伏集群汇聚规模的分层顺序,得到装机容量... 持续功率曲线能反映长时间波动特性规律,通过研究已建设光伏集群持续功率曲线,建立预测模型揭示不同规模集群的汇聚演化规律,最终得到待建光伏集群的持续功率曲线。首先,利用层次聚类算法确定光伏集群汇聚规模的分层顺序,得到装机容量逐层递增的光伏集群,并提出汇聚效应指标验证顺序的有效性;其次,为了更好地判断和预测光伏持续功率曲线的变化趋势,对持续功率曲线进行出力场景划分;最后,为避免单一模型预测偏差,在各出力场景下,通过改进的信息熵组合预测模型掌握汇聚过程中规模演变规律,完成规划待建设集群持续功率曲线的预测。利用河北某地区实测数据仿真结果表明:验证聚类方法得到的集群分层顺序更能体现汇聚效应,并有效提高预测精度;出力场景划分准确刻画集群持续功率曲线汇聚趋势;通过模型对比表明分场景下改进信息熵组合预测模型更能精确完成待建光伏集群持续功率特性的量化分析。 展开更多
关键词 光伏发电 集群层级划分 汇聚效应 持续功率曲线 组合预测
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煤矿井下爆炸性环境下电磁波热效应的安全性研究 被引量:1
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作者 郭波超 田子建 +2 位作者 侯明硕 石洋名 杨维 《工矿自动化》 CSCD 北大核心 2024年第3期108-113,共6页
GB/T 3836.1—2021《爆炸性环境第1部分:设备通用要求》规定爆炸性环境中射频设备的阈功率不得大于6 W,该规定限制了大功率射频设备在煤矿井下的应用,而现有针对爆炸性环境电磁安全性的相关研究缺乏完善的理论分析和实验验证。针对上述... GB/T 3836.1—2021《爆炸性环境第1部分:设备通用要求》规定爆炸性环境中射频设备的阈功率不得大于6 W,该规定限制了大功率射频设备在煤矿井下的应用,而现有针对爆炸性环境电磁安全性的相关研究缺乏完善的理论分析和实验验证。针对上述问题,推导了电磁波热效应方程,分析得出影响电磁波耦合瓦斯和煤尘混合气体产生热能的可控参数为电磁波耦合时间、电场强度和电磁波频率。以GB/T 3836.1—2021中可能堆积煤尘的电气设备表面温度最高不能超过150℃的规定为依据,采用多物理场仿真软件COMSOL对不同发射功率的电磁波耦合瓦斯和煤尘混合气体的热效应安全性进行了仿真实验,结果表明:满足温度不超过150℃的电磁波热效应安全阈发射功率为16.48 W;随着电磁波发射功率的增加,电磁波热效应安全时长(电磁波耦合瓦斯和煤尘混合气体产生的热能不会使环境温度超过150℃对应的时间段)逐渐减少,但只要在安全时长内,电磁波的发射功率不受限制。 展开更多
关键词 煤矿井下 电磁波热效应 瓦斯 阈功率 安全时长
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华北平原及沿山和沿海五个城市夏季短历时降水过程的日变化分析 被引量:1
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作者 丁乙 窦晶晶 +2 位作者 王迎春 苗世光 樊利强 《气象学报》 CAS CSCD 北大核心 2024年第4期490-509,共20页
利用华北平原294个国家级气象站1980—2022年夏季(6—8月)逐时降水资料,分析了华北平原夏季短历时降水过程的日变化时、空分布特征,结合地面气温和风的日变化,综合分析了4个沿山城市(北京、石家庄、济南、郑州)和1个沿海城市(天津)在城... 利用华北平原294个国家级气象站1980—2022年夏季(6—8月)逐时降水资料,分析了华北平原夏季短历时降水过程的日变化时、空分布特征,结合地面气温和风的日变化,综合分析了4个沿山城市(北京、石家庄、济南、郑州)和1个沿海城市(天津)在城市发展前期(1980—1989年)和后期(2013—2022年)短历时降水过程日变化特征及差异。结果表明:华北平原短历时降水过程整体呈现傍晚单峰的日变化特征;平原站点的达峰时间自东南向西北推后。5个主要城市在城市发展后期,短历时降水过程的日振幅都出现不同程度的减小;沿山城市短历时降水过程日峰值出现时间提前了1—2 h,而沿海城市天津无明显峰值时间,且高值时段提前;沿山城市50 mm以上短历时降水过程概率均有所升高,其中北京和石家庄40 mm以上的降水过程概率分别升高了2倍和5倍,而沿海城市天津40 mm以上的降水过程概率下降了43%。华北平原短历时降水过程的日变化与局地地形的热、动力作用和地面盛行风有关。城市局地增温效应导致沿山、沿海城市与周围地形热力差异更加明显,增强了沿山城市的山风和沿海城市的海风;同时,城市增温导致城市午后地面风辐合增强。近地面层上述热力差异变化导致的风场变化可能是沿山城市短历时降水过程日峰值提前、沿海城市短历时降水过程集中时段变为白天的重要原因。 展开更多
关键词 短历时降水过程 日变化 城市效应 地形 华北平原
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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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“毒品”还是“良药”?电子竞技对大学生执行功能影响的时间剂量效应
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作者 袁诗婧 鲁长芬 +1 位作者 马媛 罗小兵 《武汉体育学院学报》 CSSCI 北大核心 2024年第8期73-80,共8页
为探究电子竞技提升大学生执行功能的有效和最佳时间剂量,以当下市场受欢迎度最高的移动端MOBA游戏——王者荣耀作为干预手段,先后展开两组不同持续时间的单次电子竞技游戏影响大学生执行功能的实验。预实验采用4(组别:干预30分钟、60... 为探究电子竞技提升大学生执行功能的有效和最佳时间剂量,以当下市场受欢迎度最高的移动端MOBA游戏——王者荣耀作为干预手段,先后展开两组不同持续时间的单次电子竞技游戏影响大学生执行功能的实验。预实验采用4(组别:干预30分钟、60分钟、90分钟、120分钟)×2(时间:前测、后测)两因素混合实验设计,采用Flanker、2-back和More-odd shifting任务分别测量被试执行功能三个子功能,41名大学生完成了实验。在发现120分钟组干预无效后,正式实验设计了对照组、30分钟实验组、60分钟实验组和90分钟实验组,进行干预前后两次执行功能测验,108名大学生最终被纳入分析。结果发现:单次持续30分钟或60分钟的电子竞技干预即可显著提升大学生执行功能各子功能,且30分钟效果更佳;一旦达90分钟将无效果,甚至对部分子功能有负面影响。因此,建议大学生参与电子竞技游戏的时间以每次30分钟为佳,不宜超过60分钟。 展开更多
关键词 电子竞技 动作电子游戏 大学生 抑制控制 工作记忆 认知灵活性 时间剂量效应
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缺血缺氧脑瘫大鼠的时效研究
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作者 米晓阳 单海军 +4 位作者 介小素 廖伟伟 曹彩红 张英英 侯玉晋 《世界中医药》 CAS 北大核心 2024年第5期633-637,共5页
目的:基于缺血缺氧脑瘫大鼠神经功能评分(Zea-Longa评分)、脑组织肉眼观和大脑海马区胱天蛋白酶-9(Caspase-9)、胱天蛋白酶-3(Caspase-3)的表达水平变化,探讨缺血缺氧模型脑瘫大鼠的有效时长。方法:选取3周龄斯泼累格·多雷(SD)健... 目的:基于缺血缺氧脑瘫大鼠神经功能评分(Zea-Longa评分)、脑组织肉眼观和大脑海马区胱天蛋白酶-9(Caspase-9)、胱天蛋白酶-3(Caspase-3)的表达水平变化,探讨缺血缺氧模型脑瘫大鼠的有效时长。方法:选取3周龄斯泼累格·多雷(SD)健康大鼠,随机分为正常组和模型组,采用改良的Rice-Vannucci方法建立脑瘫模型,造模后第1、7、14、21天,观察各组大鼠的一般情况并进行神经功能评分,在第7、14、21天分批处死大鼠并取脑组织,观察各组大鼠左侧脑组织,检测海马区Caspase-9、Caspase-3的表达水平。结果:一般情况:造模后第1天,与正常组比较,模型组大鼠左侧瞳孔缩小、姿势异常、自发或夹尾左旋、自主活动减少、兴奋性降低、肌肉颤动、头颤,抽搐,抓取时抵抗反应明显,随着时间延长,以上异常行为逐渐消失,造模后21 d基本消失不见,但左侧瞳孔一直小于对侧;Zea-Longa评分:与正常组比较,模型组造模后7、14 d Zea-Longa评分较高,差异有统计学意义(P<0.05);脑组织肉眼观:与正常组比较,模型组造模后7、14及21 d大鼠左侧脑组织有不同程度的萎缩和坏死;免疫组化结果:与正常组比较,模型组造模后7 d、14 d Caspase-9、Caspase-3的表达水平均显著升高,差异有统计学意义(P<0.05)。结论:3周龄缺血缺氧脑瘫模型大鼠的有效时长为14~21 d,可干预14 d。 展开更多
关键词 缺血缺氧模型 脑瘫大鼠 有效时长 一般情况 神经功能评分 脑组织肉眼观 胱天蛋白酶-9 胱天蛋白酶-3
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丁香酚对细鳞裂腹鱼幼鱼的麻醉效果研究
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作者 左鹏翔 金方彭 +8 位作者 冷云 王志飞 吴俊颉 于虹漫 邓育林 祖学鹏 李明辉 王建波 张星海 《中国农学通报》 2024年第5期159-164,共6页
探索丁香酚对细鳞裂腹鱼(Schizothorax chongi)幼鱼的麻醉效果,为其生产和分子取样等提供参考。采用静水法研究幼鱼在丁香酚溶液中,不同浓度、不同药浴时间、不同空气中暴露时间下细鳞裂腹鱼幼鱼麻醉与复苏情况。结果表明,丁香酚浓度与... 探索丁香酚对细鳞裂腹鱼(Schizothorax chongi)幼鱼的麻醉效果,为其生产和分子取样等提供参考。采用静水法研究幼鱼在丁香酚溶液中,不同浓度、不同药浴时间、不同空气中暴露时间下细鳞裂腹鱼幼鱼麻醉与复苏情况。结果表明,丁香酚浓度与麻醉时间呈负相关,浓度与麻醉时间关系式:y_(1)=286.63e^(-0.0135x),R^(2)=0.9593;幼鱼复苏时间与丁香酚浓度呈正相关,浓度与复苏时间相关式:y_(2)=101.54e^(0.0134x),R^(2)=0.9913,不同浓度下幼鱼的麻醉时间和复苏时间均呈显著性差异(P<0.05),40 mg/L浓度丁香酚药浴中,幼鱼药浴时间与复苏时间呈正相关,复苏时间与药浴时间关系式:y=64.647x^(0.2394),R^(2)=0.9823,不同时长下复苏时间呈现显著性差异(P<0.05),40 mg/L浓度下,幼鱼在空气中暴露时长和复苏时间呈负相关,麻醉后的幼鱼在空气中的暴露时间与复苏时间的关系为y=900.92x^(-0.4078),R^(2)=0.8961,不同暴露时间下的复苏时长呈现显著性差异(P<0.05)。细鳞裂腹鱼的生产、运输、取样等研究中,丁香酚浓度为40~80 mg/L,麻醉效果最佳;幼鱼药浴时间不能超600 s;幼鱼在空气中暴露时间不超过1200 s。 展开更多
关键词 丁香酚 细鳞裂腹鱼 麻醉效果 暴露时长 复苏时长
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俯卧位与翻身时长对烧伤合并急性呼吸窘迫综合征机械通气患者的影响
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作者 王容容 林静 +3 位作者 庄玉娇 董雅萍 苏晓玲 李馨 《护理实践与研究》 2024年第6期886-891,共6页
目的 探讨烧伤合并急性呼吸窘迫综合征(ARDS)机械通气患者不同俯卧位与翻身时长对治疗效果的影响。方法 选取2021年6—12月医院烧伤合并ARDS机械通气患者41例作为对照组,采取俯卧位与平卧位均为2 h并交替翻身3次,俯卧位累计6 h;选取2022... 目的 探讨烧伤合并急性呼吸窘迫综合征(ARDS)机械通气患者不同俯卧位与翻身时长对治疗效果的影响。方法 选取2021年6—12月医院烧伤合并ARDS机械通气患者41例作为对照组,采取俯卧位与平卧位均为2 h并交替翻身3次,俯卧位累计6 h;选取2022年1—6月收治的相同疾病患者38例作为观察组,采取俯卧4 h→平卧2 h→俯卧4 h→平卧,俯卧位时间长为8 h。观察对比1周内两组患者的血气分析结果、住院时间、Braden量表评分。结果 更改俯卧位与翻身时长后的第7天,观察组患者的动脉血氧分压(PaO_(2))、氧合指数(PaO_(2)/FiO_(2))均高于对照组,差异具有统计学意义(P<0.05);观察组患者的动脉血二氧化碳分压(PaCO_(2))低于对照组,差异具有统计学意义(P<0.05);观察组患者住院时间短于对照组,Braden评分高于对照组,差异具有统计学意义(P<0.05)。结论 通过平卧2 h与俯卧4 h交替翻身2次,共俯卧位8 h,可改善患者血气指标,减轻皮肤压力性损伤,缩短住院时间。 展开更多
关键词 烧伤 俯卧位通气 翻身时长 交替翻身 效果
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