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Effect of site amplifi cation on inelastic seismic response 预览
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作者 Adhikary S Singh Y 《地震工程与工程振动:英文版》 SCIE EI CSCD 2019年第3期535-554,共20页
The available models for eff ective periods of site and structure are reviewed in context of frequency tuning in the inelastic seismic response of soil-structure system. The eff ect of seismic intensity and ductility ... The available models for eff ective periods of site and structure are reviewed in context of frequency tuning in the inelastic seismic response of soil-structure system. The eff ect of seismic intensity and ductility demand, on the eff ective periods, is investigated, and inelastic site amplifi cation is shown to be strongly correlated to the normalized eff ective period. Two non-dimensional parameters, analogous to the conventional site amplifi cation factors in codes, are defi ned to quantify the inelastic site amplifi cation. It is shown that the inelastic site amplifi cation factor (i.e. ratio of constant ductility spectral ordinates at soil site to those at rock outcrop) is able to represent the site eff ects more clearly, as compared to the inelastic site amplifi cation ratio (i.e. ratio of inelastic spectral ordinates at soil site to the corresponding elastic spectral ordinates at rock outcrop). Further, the peak in the amplifi cation factor corresponding to the eff ective site period diminishes rapidly with increasing ductility demand. 展开更多
关键词 SITE amplifi CATION normalized RESPONSE SPECTRA eff ective period INELASTIC SEISMIC RESPONSE INELASTIC SITE amplifi CATION factor
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Effects of adjuvant Qishen Yiqi Drop Pill therapy on renal function changes and prognosis of patients with early diabetic nephropathy
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作者 Jun Li Xiao-Hong Zhang 《海南医科大学学报(英文版)》 2019年第3期31-35,共5页
Objective: To study the effects of adjuvant Qishen Yiqi Drop Pill therapy on renal function changes and prognosis of patients with early diabetic nephropathy. Methods: The patients with early diabetic nephropathy trea... Objective: To study the effects of adjuvant Qishen Yiqi Drop Pill therapy on renal function changes and prognosis of patients with early diabetic nephropathy. Methods: The patients with early diabetic nephropathy treated in our hospital between February 2015 and April 2017 were chosen and divided into two groups by random number table, observation group received Qishen Yiqi Drop Pill combined with conventional therapy and control group accepted conventional therapy. The renal function indexes, cytokine contents and oxygen free radical generation were compared before treatment and 3 months after treatment. Results:Urine UREA levels as well as serum β2 microglobulin (β2-MG), cystatin C (CysC), tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6), stromal cell-derived factor-1 (SDF-1), interleukin-17 (IL-17), transforming growth factor-β1 (TGF-β1), malondialdehyde (MDA) and 8-iso-prostaglandin F2α (8-iso-PGF2α) contents of both groups were significantly lower while superoxide dismutase (SOD) and total antioxidant capacity (T-AOC) contents were significantly higher after treatment, and urine UREA level as well as serum β2-MG, CysC, TNF-α, IL-6, SDF-1, IL-17, TGF-β1, MDA and 8-iso-PGF2α contents of observation group after treatment was significantly lower than those of control group while SOD and T-AOC contents were significantly higher than those of control group. Conclusion: Adjuvant Qishen Yiqi Drop Pill therapy can improve the renal function and reduce the inflammatory response and oxidative stress response in early diabetic nephropathy. 展开更多
关键词 DIABETIC NEPHROPATHY Qishen Yiqi DROP PILL Renal function Inflammatory RESPONSE Oxidative stress RESPONSE
Temperature-induced hormesis in plants 预览
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作者 Evgenios Agathokleous Mitsutoshi Kitao +1 位作者 Hisanori Harayama Edward J.Calabrese 《林业研究:英文版》 CAS CSCD 2019年第1期13-20,共8页
Environmental change attracts particular attention by biologists concerned with the performance of biological systems under stress.To investigate these,dose– response relationships should be clarified.It was previous... Environmental change attracts particular attention by biologists concerned with the performance of biological systems under stress.To investigate these,dose– response relationships should be clarified.It was previously assumed that the fundamental nature of biological dose– responses follows a linear model,either with no threshold or with a threshold below which no effects are expected to occur in biological endpoints.However,substantial literature,including widespread documentation in plants,has revealed that hormesis commonly occurs.Hormesis is highly generalized and can be utilized as a quantitative measure of biological plasticity.Conditioning induced by adaptive responses also occurs in the framework of hormesis and is of particular importance to environmental change biology with regards to evolutionary adaptations.This paper presents additional evidence for hormetic dose responses induced by temperature in plants.The current understanding on hormesis provides a perspective for next generation environmental change research.Hormesis should have a central role in environmental change biology of vegetation. 展开更多
关键词 Adaptive RESPONSE Biological PLASTICITY DOSE RESPONSE HORMESIS Stress BIOLOGY
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Design of Computationally Efficient Sharp FIR Filter Utilizing Modified Multistage FRM Technique for Wireless Communications Systems 预览
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作者 Tirthadip Sinha Jaydeb Bhaumik 《电子科技学刊:英文版》 CAS CSCD 2019年第2期185-192,共8页
Modern wireless communications gadgets demand multi-standard communications facilities with least overlap between different input radio channels. A sharp digital filter of extremely narrow transition-width with lower ... Modern wireless communications gadgets demand multi-standard communications facilities with least overlap between different input radio channels. A sharp digital filter of extremely narrow transition-width with lower stop band ripples offers alias-free switching among the preferred frequency bands. A computationally competent low pass filter (LPF) structure based on the multistage frequency response masking (FRM) approach is proposed for the design of sharp finite impulse response (FIR) filters which are suitable for wireless communications applications. In comparison of basic FRM with other existing multistage FRM structures, the proposed structure has a narrow transition bandwidth and higher stop band attenuation with significant reduction in terms of the number of computational steps. A design example is incorporated to demonstrate the efficiency of the proposed approach. Simulation results establish the improvement of the proposed scheme over other recently published design strategies. 展开更多
关键词 MULTISTAGE frequency RESPONSE MASKING narrow transition-width SHARP finite IMPULSE RESPONSE filter wireless communications
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A time-domain nonlinear effective-stress non-Masing approach of ground response analysis of Guwahati city, India 预览
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作者 Devdeep Basu Madhulatha Boga Arindam Dey 《地震工程与工程振动:英文版》 SCIE EI CSCD 2019年第1期61-75,共15页
The response of subsoil strata subjected to seismic excitations plays an important role in governing the response of the overlying superstructures at any site. Ground response analysis(GRA) helps to assess the influen... The response of subsoil strata subjected to seismic excitations plays an important role in governing the response of the overlying superstructures at any site. Ground response analysis(GRA) helps to assess the influence of soil characteristics on the propagating seismic stress waves from the bedrock level to the ground surface during an earthquake. For the northeastern region of India, located in the highest seismic zone in the country, conducting an extensive GRA study is of prime importance. Conventionally, most of the GRA studies are carried out using the equivalent linear method, which, being a simplistic approach, cannot capture the nonlinear behavior of soil during seismic shaking. This paper presents the outcomes of a one-dimensional effective stress based nonlinear GRA conducted for Guwahati city(located in northeast India) incorporating the non-Masing load/unload/reload characteristics. The various ground response parameters evaluated from this study help in assessing the ground shaking, soil amplification, and site responses expected in this region. 2D contour maps, which are representative of the distribution of some of these parameters throughout Guwahati city, are also developed. The results presented herein can serve as guidelines for the design of foundations and superstructures in this region. 展开更多
关键词 GROUND RESPONSE analysis nonlinear effective STRESS APPROACH non-masing criteria GROUND RESPONSE parameters soil amplification
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Volatiles from Sophora japonica flowers attract Harmonia axyridis adults(Coleoptera:Coccinellidae) 预览
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作者 XIU Chun-li XU Bin +3 位作者 PAN Hong-sheng ZHANG Wei YANG Yi-zhong LU Yan-hui 《农业科学学报:英文版》 SCIE CAS CSCD 2019年第4期873-883,共11页
The multicolored Asian lady beetle,Harmonia axyridis(Coleoptera:Coccinellidae),is a common generalist predator in China and is occasionally found gathering on the Chinese pagoda tree,Sophora japonica,in summer.In a fi... The multicolored Asian lady beetle,Harmonia axyridis(Coleoptera:Coccinellidae),is a common generalist predator in China and is occasionally found gathering on the Chinese pagoda tree,Sophora japonica,in summer.In a field investigation,we found that H.axyridis adults preferred S.japonica during its flowering period even though their optimal prey(aphid)is absent at this time.In addition,male and female adults were attracted to S.japonica flowers to a similar extent in a Y-tube olfactometer assay.Using coupled gas chromatography-electroantennogram detection(GC-EAD),we identified a flower odor component(nonanal)that elicited a significant electrophysiological response in H.axyridis.Electroantennogram(EAG)dose-dependent responses revealed that the amplitude of the adult beetle’s EAG response increased with increasing concentration of nonanal,peaking at 10 mg mL^–1.In Y-tube olfactometer behavioral tests,H.axyridis adults preferred a 10 mg mL^–1 nonanal source over a 100 mg mL^–1 diluent.Under field conditions,the adults were significantly attracted to both concentrations(10 and 100 mg mL^–1),and high concentrations generally had greater attraction.All these results suggest that nonanal,a volatile compound of S.japonica flowers,greatly attracts H.axyridis adults.This study provides a basis for the development of synthetic attractants of H.axyridis,with the potential to promote biocontrol services of this generalist predator in the native area(e.g.,China)and to suppress its population by mass trapping in its invasive areas. 展开更多
关键词 flower preference plant volatile electrophysiological RESPONSE BEHAVIORAL RESPONSE ATTRACTANTS
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Nomograms for predicting pathological response to neoadjuvant treatments in patients with rectal cancer 预览
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作者 Dong-Lin Ren Juan Li +5 位作者 Hui-Chuan Yu Shao-Yong Peng Wei-Da Lin Xiao-Lin Wang Roshan Ara Ghoorun Yan-Xin Luo 《世界胃肠病学杂志:英文版》 SCIE CAS 2019年第1期118-137,共20页
BACKGROUND In recent decades,neoadjuvant therapy(NT)has been the standardized treatment for locally advanced rectal cancer(LARC).Approximately 8%-35%of patients with LARC who received NT were reported to have achieved... BACKGROUND In recent decades,neoadjuvant therapy(NT)has been the standardized treatment for locally advanced rectal cancer(LARC).Approximately 8%-35%of patients with LARC who received NT were reported to have achieved a complete pathological response(pCR).If the pathological response(PR)can be accurately predicted,these patients may not need surgery.In addition,no response after NT implies that the tumor is destructive,resistant to both chemotherapy and radiotherapy,and prone to having a high metastatic potential.Therefore,developing accurate models to predict PR has great clinical significance and can help achieve individualized treatment in LARC patients.AIM To establish nomograms for predicting PR to different NT regimens based on pretreatment parameters for patients with LARC.METHODS Rectal cancer patients were identified from the database of The Sixth Affiliated Hospital,Sun Yat-sen University from January 2012 to December 2016.Logistic regression and nomograms were developed to predict the probability of pCR and good downstaging to ypT0-2N0M0(ypTNM 0-I),respectively,based on pretreatment parameters for all LARC patients.Nomograms were also developed for three NT regimens(capecitabine/deGramont-RT,mFOLFOX6,and mFOLFOX6-RT)to predict pCR probability.RESULTS Four hundred and three patients were included in this study;72(17.9%)had pCR at the final pathology report,and 177(43.9%)achieved good downstaging to ypT0-2N0M0(ypTNM 0-I).The nomogram for predicting pCR probability showed that NT regimens,tumor differentiation,mesorectal fascia(MRF)status,and tumor length significantly influenced pCR probability.When predicting the probability of good downstaging,tumor differentiation,MRF status,and clinical T stage were the significant factors.Nomograms were developed based on NT regimens.For the capecitabine/de Gramont-RT group,the multivariate analysis showed that the neutrophil-lymphocyte ratio(NLR)was the only significant factor,thus we could not develop a nomogram for this regimen.For the mFOLFOX6-RT group,the analy 展开更多
关键词 NEOADJUVANT therapy Locally advanced rectal cancer NOMOGRAM Prediction of PATHOLOGICAL RESPONSE Complete PATHOLOGICAL RESPONSE Good DOWNSTAGING
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Relationship between the high frequency of 23S rRNA point mutations in Treponema pallidum and low serological response rate to azithromycin treatment in China
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作者 Rui-Li Zhang Qian-Qiu Wang +5 位作者 Zhi-Ju Zheng Guo-Jun Liang Li-Jia Yang Li-Gang Yang Dong-Nu Pei Shao-Chun Lin 《国际皮肤性病学杂志(英文)》 2019年第1期6-14,共9页
Objective Although azithromycin is effective against Treponema pallidum (T.pallidum),the causative agent of syphilis,recent reports indicate that the prevalence of azithromycin resistance in China is very high,which m... Objective Although azithromycin is effective against Treponema pallidum (T.pallidum),the causative agent of syphilis,recent reports indicate that the prevalence of azithromycin resistance in China is very high,which may result in the failure of treatment.In this study,we aimed to investigate the association between azithromycin resistance and therapeutic outcomes in early syphilis patients.Methods Between February 2010 and December 2014,patients aged 18-65 years with early syphilis were enrolled.T.pallidum DNA were extracted to test the presence of A2058G and A2059G mutations.Then,eligible patients were randomly assigned to receive oral azithromycin (0.5 g,once daily for 15 days) or intramuscular BPG (2.4 million units,once weekly for 3 weeks).All patients were followed up in 2 weeks and 3,6,9,and 12 months after treatment to collect demographic and clinical characteristics and laboratory results.The differences on serological response,serological failure and serofast rate were compared between the two groups by Chi-square test.Results Among the 187 T.pallidum-infected patients enrolled,172 (92.0%) cases had a mutation associated with azithromycin resistance (A2058G,153 cases;A2059G,19 cases).During the 5-year study period,the percentage of cases enrolled with these mutations steadily increased,from 90.9% in 2010 to 95.3% in 2014.Of the 172 patients presenting with these mutations,only 78 (45.3%;all benzathine penicillin G [BPG]-treated) obtained a serological response to treatment;32.6% and 22.1% of patients presented with serological failure and serofast results,respectively.For azithromycin-treated cases,66.3% and 33.7% had serological failure and serofast results,respectively,in contrast with 1.1% and 11.3% of BPG-treated cases.However,among the A2058G-and A2059G-negative patients,the serological response rates between the two treatment groups were similar.In multivariate analyses,patients with lower rapid plasma reagin (RPR) titers (RPR,≤ 1 ∶ 8;odds ratio [OR],0.23;95% confidence interval [CI],0.09-0.37) 展开更多
关键词 SYPHILIS AZITHROMYCIN MUTATION SEROLOGICAL response TREPONEMA PALLIDUM
Effectiveness of taxanes over anthracyclines in neoadjuvant setting: A systematic-review and meta-analysis 预览
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作者 Mona Pathak Sada Nand Dwivedi +3 位作者 SVS Deo Bhaskar Thakur Vishnubhatla Sreenivas Goura Kishor Rath 《世界荟萃分析杂志》 2019年第4期170-183,共14页
BACKGROUND Anthracyclines and taxanes are more active group of chemotherapy regimen. Randomized controlled trials (RCTs) reported variable evidences regarding efficacy of taxanes over anthracyclines for tumor response... BACKGROUND Anthracyclines and taxanes are more active group of chemotherapy regimen. Randomized controlled trials (RCTs) reported variable evidences regarding efficacy of taxanes over anthracyclines for tumor response and survival outcomes. The present study compares the relative efficacy of taxanes over anthracyclines using pathological complete response (pCR), clinical responses, breast-conserving surgeries and survival outcomes in female breast cancer patients by systematic review and meta-analysis of available RCTs. AIM To assess the effectiveness of taxanes over anthracyclines in neoadjuvant setting in terms of tumor response and survival outcomes. METHODS All RCTs assessing efficacy of taxanes over anthracyclines in neoadjuvant setting for management of breast cancer searched through PubMed and Cochrane register of controlled trials on 28 April 2017 and published in English language were considered. Following PRISMA guideline, retrieved records were screened and data were extracted by two independent reviewers. Meta-analysis was performed using fixed effect or random effect method depending on heterogeneity assessed using I2 statistic. Subgroup meta-analyses on the basis of taxane alone or taxane along with anthracycline in comparison to anthracycline alone were also performed for each considered outcomes.A total of 16 RCTs involving 6752 breast cancer patients were found eligible. Taxanes based chemotherapy significantly improved pCR (n = 7, RR = 1.48, 95%CI: 1.04-2.12), disease free survival [n = 6, RR = 0.89 (0.80-0.99)] and locoregional recurrence free survival [n = 4, RR = 0.74 (0.59-0.94)]. Interestingly in subgroup analysis, addition of taxane to anthracyclines showed better effectiveness regarding these survivals over anthracyclines than taxane alone over anthracycline. CONCLUSION Addition of taxanes to anthracyclines based chemotherapy significantly improves pCR, disease free survival and loco-regional recurrence free survival but with no significant impact on breast conservation rates. 展开更多
关键词 DOCETAXEL Paclitaxel EPIRUBICIN Doxorubicin Pathological complete response Breast CONSERVING surgery
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内蒙古气温变暖停滞对其影响因子变化的响应 预览
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作者 孙柏林 马龙 +5 位作者 冯起 刘廷玺 梁珑腾 李虹雨 周莹 柳杨 《中国环境科学》 EI CAS CSCD 北大核心 2019年第5期2131-2142,共12页
采用中心聚类、M-K检验等方法,以内蒙古地区为例,利用全球Pacific Decadal Oscillation(PDO)、Multivariate ENSO Index(MEI)等大空间尺度数据以及内蒙古及其周边70个气象站1951~2016年平均最低气温、平均气温、平均最高气温、风速、大... 采用中心聚类、M-K检验等方法,以内蒙古地区为例,利用全球Pacific Decadal Oscillation(PDO)、Multivariate ENSO Index(MEI)等大空间尺度数据以及内蒙古及其周边70个气象站1951~2016年平均最低气温、平均气温、平均最高气温、风速、大气压等站点数据,定性、定量揭示变暖停滞的变化特征及其对影响因子变化的响应.结果表明:研究区各分区3类气温在1981~1993年间发生升温突变,此后1998~2008年间陆续发生变暖停滞.不同类型气温在不同分区与各影响因子的相关性优劣有所不同,如平均最低气温与AMO、PDO、MEI、太阳总辐射、风速、大气压的相关性最好,平均气温次之,平均最高气温最差;西部区气温与AMO、PDO、MEI、太阳总辐射相关性较好,中部区气温则与AMO、风速相关性较好等.整体上,1990s~2000s,随各分区AMO上升驱缓、PDO处于正位相阶段但呈下降趋势或处于负位相时、MEI值与太阳总辐射下降、风速、大气压、相对湿度的持续下降/上升及之后的趋势转变,各分区气温发生变暖停滞,如当AMO开始整体进入上升趋缓阶段,风速持续减小8~13a,倾向率达到-0.26~-0.11m/(s·10a)时,平均气温发生变暖停滞.平均最低气温对3类影响因子变化的响应最敏感,平均气温次之.气温变暖停滞是多种影响因子共同作用的结果.本研究丰富了该方面研究成果,对气候变化研究及防灾减灾等有一定借鉴意义. 展开更多
关键词 气温 变暖停滞 响应 内蒙古
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Evaluation of SWAT Model performance on glaciated and non-glaciated subbasins of Nam Co Lake, Southern Tibetan Plateau, China
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作者 Muhammad ADNAN KANG Shi-chang +3 位作者 ZHANG Guo-shuai Muhammad Naveed ANJUM Muhammad ZAMAN ZHANG Yu-qing 《山地科学学报:英文版》 SCIE CSCD 2019年第5期1075-1097,共23页
This paper presents an assessment of the Soil and Water Assessment Tool(SWAT) on a glaciated(Qugaqie) and a non-glaciated(Niyaqu) subbasin of the Nam Co Lake. The Nam Co Lake is located in the southern Tibetan Plateau... This paper presents an assessment of the Soil and Water Assessment Tool(SWAT) on a glaciated(Qugaqie) and a non-glaciated(Niyaqu) subbasin of the Nam Co Lake. The Nam Co Lake is located in the southern Tibetan Plateau, two subbasins having catchment areas of 59 km~2 and 388 km~2, respectively. The scores of examined evaluation indices(i.e., R~2, NSE, and PBIAS) established that the performance of the SWAT model was better on the monthly scale compared to the daily scale. The respective monthly values of R~2, NSE, and PBIAS were 0.94, 0.97, and 0.50 for the calibration period while 0.92, 0.88, and -8.80 for the validation period. Glacier melt contribution in the study domain was simulated by using the SWAT model in conjunction with the Degree Day Melt(DDM) approach. The conjunction of DDM with the SWAT Model ensued improved results during both calibration(R~2=0.96, NSE=0.95, and PBIAS=-13.49) and validation (R~2=0.97, NSE=0.96, and PBIAS=-2.87) periods on the monthly time scale. Average contribution(in percentage) of water balance components to the total streamflow of Niyaqu and Qugaqie subbasins was evaluated. We found that the major portion(99.45%) of the streamflow in the Niyaqu subbasin was generated by snowmelt or rainfall surface runoff(SURF_Q), followed by groundwater(GW_Q, 0.47%), and lateral(LAT_Q, 0.06%) flows. Conversely, in the Qugaqie subbasin, major contributor to the streamflow(79.63%) was glacier melt(GLC_Q), followed by SURF_Q(20.14%), GW_Q(0.13%), and LAT_Q(0.089%). The contribution of GLC_Q was the highest(86.79%) in July and lowest(69.95%) in September. This study concludes that the performance of the SWAT model in glaciated catchment is weak without considering glacier component in modeling;however, it performs reasonably well in non-glaciated catchment. Furthermore, the temperature index approach with elevation bands is viable in those catchments where streamflows are driven by snowmelt. Therefore, it is recommended to use the SWAT Model in conjunction with DDM or energy base model to simulat 展开更多
关键词 SWAT MODEL NAM Co Lake DEGREE-DAY MELT MODEL Streamflow HYDROLOGICAL Response Unit
Sliding mode control design for oblique wing aircraft in wing skewing process
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作者 Ting YUE Zijian XU +1 位作者 Lixin WANG Tong WANG 《中国航空学报:英文版》 SCIE EI CAS CSCD 2019年第2期263-271,共9页
When the wing of Oblique Wing Aircraft(OWA) is skewed, the center of gravity, inertia and aerodynamic characteristics of the aircraft all significantly change, causing an undesirable flight dynamic response, affecting... When the wing of Oblique Wing Aircraft(OWA) is skewed, the center of gravity, inertia and aerodynamic characteristics of the aircraft all significantly change, causing an undesirable flight dynamic response, affecting the flying qualities, and even endangering the flight safety. In this study,the dynamic response of an OWA in the wing skewing process is simulated, showing that the threeaxis movements of the OWA are highly coupled and present nonlinear characteristics during the wing skewing. As the roll control efficiency of the aileron decreases due to the shortened control arm in an oblique configuration, the all-moving horizontal tail is used for additional roll and the control allocation is performed based on minimum control energy. Given the properties of pitchroll-yaw coupling and control input and state coupling, and the difficulty of establishing an accurate aerodynamic model in the wing skewing process due to unsteady aerodynamic force, a multi-loop sliding mode controller is formulated by the time-scale separation method. The closed-loop simulation results show that the asymmetric aerodynamics can be balanced and that the velocity and altitude of the aircraft maintain stable, which means that a smooth transition is obtained during the OWA’s wing skewing. 展开更多
关键词 DECOUPLING Dynamic response OBLIQUE WING AIRCRAFT Sliding mode control WING SKEWING PROCESS
Seismic performance evaluation of typical dampers designed by Chinese building code 预览
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作者 Guo Wei Wu Jun +2 位作者 Hu Yao Li Yunsong Yang T.Y. 《地震工程与工程振动:英文版》 SCIE EI CSCD 2019年第2期433-446,共14页
Adding dampers is a commonly adopted seismic risk mitigation strategy for modern buildings, and the corresponding design procedure of dampers has been well established by the Chinese Building Code. Even though all typ... Adding dampers is a commonly adopted seismic risk mitigation strategy for modern buildings, and the corresponding design procedure of dampers has been well established by the Chinese Building Code. Even though all types of dampers are designed by the same procedure, actual seismic performance of the building may differ from one to the others. In this study, a nine-story benchmark steel building is established, and three different and typical types of dampers are designed according to the Chinese Building Code to realize structural vibration control under strong earthquake excitation. The seismic response of the prototype building equipped with a viscoelastic damper, viscous damper and buckling-restrained brace(BRB) subjected to 10 earthquake records are calculated, and Incremental Dynamic Analysis(IDA) is performed to describe progressive damage of the structure under increasing earthquake intensity. In the perspective of fragility, it shows that the viscoelastic damper has the highest collapse margin ratio(CMR), and the viscous damper provides the best drift control. Both the BRB and viscoelastic dampers can effectively reduce the floor acceleration responses in the mid-rise building. 展开更多
关键词 CHINESE building design code VISCOELASTIC DAMPER viscous DAMPER buckling-restrained BRACE seismic response FRAGILITY analysis
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19例慢性心力衰竭患者心脏再同步化治疗术后应答反应的临床观察分析 预览
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作者 陈嘉楠 张艳芳 王丽 《广州医药》 2019年第4期49-52,78共5页
目的探讨慢性心衰心脏再同步化治疗应答分布情况。方法对2007年11月-2017年11月我院收治的19例慢性心力衰竭患者采用心脏再同步化治疗的临床资料进行回顾性分析,长期追踪患者生存情况,分析心脏再同步化治疗的可能预测因子及目前存在的... 目的探讨慢性心衰心脏再同步化治疗应答分布情况。方法对2007年11月-2017年11月我院收治的19例慢性心力衰竭患者采用心脏再同步化治疗的临床资料进行回顾性分析,长期追踪患者生存情况,分析心脏再同步化治疗的可能预测因子及目前存在的问题。结果 19例患者中,10例患者CRT应答,8例患者CRT无应答,1例患者失访;应答组及无应答组基线红细胞分布宽度2组差异有统计学意义(Z=-2.981,P=0.003);而QRS波时限、肾小球滤过率、年龄、心率、血压、BMI、左室射血分数、左房内径、左室舒张末内径、右室内径、左室短轴缩短率、室间隔、左室后壁、心室舒张容量及心室收缩容量、胱抑素c、尿素、尿酸、白蛋白均无差异;心脏再同步化治疗前后,患者QRS波时限、心功能NYHA分级、左室射血分数、左室射血分数、左室短轴缩短率、左室舒张容量、左室收缩容量差异均存在统计学意义(P<0.05),而左室舒张末内径、左房内径、右室内径、心输出量则无明显变化。结论心脏再同步化治疗能够逆转患者心电及机械重塑,是慢性心衰非药物治疗的首选方法。基线红细胞宽度的增加显示心脏再同步化治疗无应答,可作为慢性心衰患者心脏再同步化治疗的预后评估因子。 展开更多
关键词 心脏再同步化治疗 心力衰竭 应答反应
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晋北农牧交错带作物气候生产潜力分布特征及其对气候变化的响应
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作者 马雅丽 郭建平 赵俊芳 《生态学杂志》 CAS CSCD 北大核心 2019年第3期818-827,共10页
选取晋北农牧交错带1961—2016年19个气象站点逐日气象资料以及1981—2016年5种粮食作物发育期观测资料,采用作物生产潜力逐级订正法,分析不同作物各级生产潜力分布特征,并基于各级生产潜力变化倾向率建立统计模型,分析辐射、气温、降... 选取晋北农牧交错带1961—2016年19个气象站点逐日气象资料以及1981—2016年5种粮食作物发育期观测资料,采用作物生产潜力逐级订正法,分析不同作物各级生产潜力分布特征,并基于各级生产潜力变化倾向率建立统计模型,分析辐射、气温、降水等气候要素变化对气候生产潜力的影响。结果表明:1961—2016年,晋北各作物光温生产潜力空间分布特征为:玉米、谷子、高粱和大豆东高西低,马铃薯空间分布差异较小;各作物气候生产潜力空间分布特征为:玉米、谷子和高粱东南高西北低,马铃薯东西高中部低,大豆空间分布差异较小;气候要素变化对不同作物气候生产潜力的影响不同,辐射变化对5种作物气候生产潜力的影响为负效应;气温变化对大部分地区喜温作物(玉米、大豆、谷子和高粱)气候生产潜力的影响为正效应,对喜凉作物马铃薯的影响是负效应,气候变暖对改善晋北地区热量不足有利;降水变化是影响晋北作物气候生产潜力变化出现明显空间差异的主要因素,降水减少对于东北部降水偏少地区的影响为负效应,而对于南部降水较多地区未表现负效应,降水基本满足作物生长需要;为适应当前气候变化,需加强高光合效率和抗旱作物品种的选育,合理密植,调整播期,优化农业布局,因地制宜地推广农业集雨灌溉和农业节水灌溉技术,以提高农业气候资源利用率,促进粮食作物稳产高产。 展开更多
关键词 作物气候生产潜力 气候变化 晋北农牧交错带 响应
科学家阐明tRNAHis鸟苷转移酶参与调控水稻适应环境温度的新机制 预览
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《江西饲料》 2019年第3期47-48,共2页
5月6日,Molecular Plant 杂志在线发表了中国科学院分子植物卓越创新中心/植物生理生态研究所林鸿宣研究组题为Translational Regulation of Plant Response to High Temperature by a Dual Function tRNAHis Guanylyltransferase in Ri... 5月6日,Molecular Plant 杂志在线发表了中国科学院分子植物卓越创新中心/植物生理生态研究所林鸿宣研究组题为Translational Regulation of Plant Response to High Temperature by a Dual Function tRNAHis Guanylyltransferase in Rice 的研究论文,揭示了水稻tRNAHis鸟苷转移酶通过参与生长素响应因子蛋白翻译调控过程适应环境温度的新机制。 展开更多
关键词 环境温度 翻译调控 转移酶 机制 水稻 鸟苷 科学家 Response
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Visual-spatial neglect after right-hemisphere stroke:behavioral and electrophysiological evidence
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作者 Lin-Lin Ye Lei Cao +3 位作者 Huan-Xin Xie Gui-Xiang Shan Yan-Ming Zhang Wei-Qun Song 《中华医学杂志:英文版》 SCIE CAS CSCD 2019年第9期1063-1070,共8页
Background:Visual-spatial neglect (VSN) is a neuropsychological syndrome,and right-hemisphere stroke is the most common cause.The pathogenetic mechanism of VSN remains unclear.This study aimed to investigate the behav... Background:Visual-spatial neglect (VSN) is a neuropsychological syndrome,and right-hemisphere stroke is the most common cause.The pathogenetic mechanism of VSN remains unclear.This study aimed to investigate the behavioral and event-related potential (ERP) changes in patients with or without VSN after right-hemisphere stroke.Methods:Eleven patients with VSN with right-hemisphere stroke (VSN group) and 11 patients with non-VSN with righthemisphere stroke (non-VSN group) were recruited along with one control group of 11 age- and gender-matched healthy participants.The visual-spatial function was evaluated using behavioral tests,and ERP examinations were performed.Results:The response times in the VSN and non-VSN groups were both prolonged compared with those of normal controls (P<0.001).In response to either valid or invalid cues in the left side,the accuracy in the VSN group was lower than that in the non-VSN group (P<0.001),and the accuracy in the non-VSN group was lower than that in controls (P<0.05).The P1 latency in the VSN group was significantly longer than that in the control group (F[2,30]= 5.494,P = 0.009),and the N1 amplitude in the VSN group was significantly lower than that in the control group (F[2,30]= 4.343,P = 0.022).When responding to right targets,the lefthemisphere P300 amplitude in the VSN group was significantly lower than that in the control group (F[2,30]= 4.255,P = 0.025).With either left or right stimuli,the bilateral-hemisphere P300 latencies in the VSN and non-VSN groups were both significantly prolonged (all P<0.05),while the P300 latency did not differ significantly between the VSN and non-VSN groups (all P > 0.05).Conclusions:Visual-spatial attention function is impaired after right-hemisphere stroke,and clinicians should be aware of the subclinical VSN.Our findings provide neuroelectrophysiological evidence for the lateralization of VSN. 展开更多
关键词 Visual-spatial NEGLECT Right-hemisphere STROKE Behavior Electrophysiology EVENT-RELATED potentials Response time
Site dependent and spatially varying response spectra 预览
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作者 Hakima Djilali Berkane Zamila Harichane +1 位作者 Erkan Celebi Sidi Mohammed Elachachi 《地震工程与工程振动:英文版》 SCIE EI CSCD 2019年第3期497-509,共13页
The goal of this study is to provide a stochastic method to investigate the eff ects of the randomness of soil properties due to their natural spatial variability on the response spectra spatial variation at sites wit... The goal of this study is to provide a stochastic method to investigate the eff ects of the randomness of soil properties due to their natural spatial variability on the response spectra spatial variation at sites with varying conditions. For this purpose, Monte Carlo Simulations are used to include the variability of both incident ground motion and soil parameters in the response spectra by mean of an appropriate coherency loss function and a site-dependent transfer function, respectively. The approach is built on the assumption of vertical propagation of SH type waves in soil strata with uncertain parameters. The response spectra are obtained by numerical integration of the governing equation of a single-degree-of-freedom (SDOF) system under non-stationary site-dependent and spatially varying ground motion accelerations simulated with non-uniform spectral densities and coherency loss functions. Numerical examples showed that randomness of soil properties signifi cantly aff ects the amplitudes of the response spectra, indicating that as the heterogeneity induced by the randomness of the parameters of the medium increases, the spectral ordinates attenuate. 展开更多
关键词 response SPECTRA RANDOMNESS SPECTRAL density Monte Carlo
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Hydrodynamic pressure on concrete face rockfill dams subjected to earthquakes 预览
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作者 Zhong-zhi Fu Sheng-shui Chen Guo-ying Li 《水动力学研究与进展:英文版》 SCIE EI CSCD 2019年第1期152-168,共17页
The hydrodynamic pressure is an important load on concrete face rockfill dams (CFRDs) subjected to earthquakes,the influence of which,however,is not clear as compared with that in concrete dams.In this paper,the coupl... The hydrodynamic pressure is an important load on concrete face rockfill dams (CFRDs) subjected to earthquakes,the influence of which,however,is not clear as compared with that in concrete dams.In this paper,the coupling effect between the CFRDs and the reservoir water is studied based on two-dimensional finite element simulations by using a verified procedure.It is found that neglecting the solid-fluid coupling effect not only results in an overestimation of the acceleration response within the rockfill materials but also makes an overestimation of the dynamical stresses in the concrete slabs.For a reliable seismic response analysis of the CFRDs,therefore,the hydrodynamic pressure should be taken into account,particularly when the dam is subjected to a simultaneous excitation in both horizontal and vertical directions.Numerical results show,however,that the compressibility of the water can be safely neglected in the seismic response analyses of the CFRDs even when the dam is as high as 300 m,except when the excitation is quite abundant in high frequency contents. 展开更多
关键词 Concrete face ROCKFILL DAM HYDRODYNAMIC pressure SEISMIC response EARTHQUAKE
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Type and distribution of Mid-Permian Maokou Formation karst reservoirs in southern Sichuan Basin,SW China 预览
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作者 HUANG Shipeng JIANG Qingchun +6 位作者 FENG Qingfu WU Ya LU Weihua SU Wang CHEN Xiaoyue REN Mengyi PENG Hui 《石油勘探与开发:英文版》 2019年第2期293-300,共8页
Based on the analysis of the responses of conventional logs such as natural gamma(GR), density(DEN), acoustic interval transit time(AC), compensated neutron(CNL), dual lateral resistivity(Rlld, Rlls), and caliper log(... Based on the analysis of the responses of conventional logs such as natural gamma(GR), density(DEN), acoustic interval transit time(AC), compensated neutron(CNL), dual lateral resistivity(Rlld, Rlls), and caliper log(CAL), combined with drilling data,cores, thin section and productivity of 65 wells, the reservoirs in the Mid-Permian Maokou Formation of southern Sichuan Basin were divided into four types, fractured-vuggy, pore-vuggy, fractured and fractured-cavity. The main reservoirs in high productivity wells are fractured-vuggy and pore-vuggy. The reservoirs of Maokou Formation are generally thin, and can be divided into the upper reservoir segment(layer a of the second member to the third member of Maokou Formation, P2 m^2 a-P2 m^3) and the lower segment(layer b of the second member of Maokou Formation, P2 m^2 b). The two reservoir segments are mainly controlled by two grain beaches during the sedimentation of P2 m^2 a-P2 m^3 and P2 m^2 b, the vertical zonation of karst, and the fractures. The upper reservoir segment is generally better than the lower one in development degree and single well productivity, and is much thicker than the lower one. It is thicker in the Yibin-Zigong-Weiyuan-Dazu area, the southwestern area of Chongqing and the southeastern area of Luzhou, while the lower segment is thicker in the Neijiang-Zigong-Luzhou area and the Dazu-Luzhou area. The areas with big reservoir thickness at tectonic slope or syncline parts are the favorable exploration areas. 展开更多
关键词 SOUTHERN Sichuan Basin Mid-Permian Maokou Formation karst reservoir cavity fracture grain BEACH logging response
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