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Preliminary report of the September 5,2022 M_(S) 6.8 Luding earthquake,Sichuan,China 被引量:4
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作者 Yanru An dun wang +12 位作者 Qiang Ma Yueren Xu Yu Li Yingying Zhang Zhumei Liu Chunmei Huang Jinrong Su Jilong Li Mingxiao Li Wenkai Chen Zhifan Wan Dengjie Kang Baoshan wang 《Earthquake Research Advances》 CSCD 2023年第1期1-10,共10页
The 2022 M_(S)6.8 Luding earthquake is the strongest earthquake in Sichuan Province, Western China, since the 2017 M_(S)7.0 Jiuzhaigou earthquake. It occurred on the Moxi fault in the southeastern segment of the Xians... The 2022 M_(S)6.8 Luding earthquake is the strongest earthquake in Sichuan Province, Western China, since the 2017 M_(S)7.0 Jiuzhaigou earthquake. It occurred on the Moxi fault in the southeastern segment of the Xianshuihe fault, a tectonically active and mountainous region with severe secondary earthquake disasters. To better understand the seismogenic mechanism and provide scientific support for future hazard mitigation, we summarize the preliminary results of the Luding earthquake, including seismotectonic background, seismicity and mainshock source characteristics and aftershock properties, and direct and secondary damage associated with the mainshock.The peak ground displacements in the NS and EW directions observed by the nearest GNSS station SCCM are ~35 mm and ~55 mm, respectively, resulting in the maximum coseismic dislocation of 20 mm along the NWW direction, which is consistent with the sinistral slip on the Xianshuihe fault. Back-projection of teleseismic P waves suggest that the mainshock rupture propagated toward south-southeast. The seismic intensity of the mainshock estimated from the back-projection results indicates a Mercalli scale of Ⅷ or above near the ruptured area,consistent with the results from instrumental measurements and field surveys. Numerous aftershocks were reported, with the largest being M_(S)4.5. Aftershock locations(up to September 18, 2022) exhibit 3 clusters spanning an area of 100 km long and 30 km wide. The magnitude and rate of aftershocks decreased as expected, and the depths became shallower with time. The mainshock and two aftershocks show left-lateral strike-slip focal mechanisms. For the aftershock sequence, the b-value from the Gutenberg-Richter frequency-magnitude relationship, h-value, and p-value for Omori’s law for aftershock decay are 0.81, 1.4, and 1.21, respectively, indicating that this is a typical mainshock-aftershock sequence. The low b-value implies high background stress in the hypocenter region. Analysis from remote sensing satellite images and UAV data shows that the distribution of earthquake-triggered landslides was consistent with the aftershock area. Numerous small-size landslides with limited volumes were revealed, which damaged or buried the roads and severely hindered the rescue process. 展开更多
关键词 Luding earthquake Moxi fault Aftershock statistics Earthquake disasters Intensity map
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Rapid assessment of the September 5,2022 M_(S)6.8 Luding earthquake in Sichuan,China 被引量:2
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作者 Dengjie Kang Wenkai Chen +1 位作者 Huaiqun Zhao dun wang 《Earthquake Research Advances》 CSCD 2023年第2期1-7,共7页
At 12:52,September 5,2022,an M_(S)6.8 earthquake occurred in Luding,Sichuan.The earthquake caused serious casualties and property loss,and was determined to have an epicenter intensity of Ⅸ degree.In this study,we us... At 12:52,September 5,2022,an M_(S)6.8 earthquake occurred in Luding,Sichuan.The earthquake caused serious casualties and property loss,and was determined to have an epicenter intensity of Ⅸ degree.In this study,we used three earthquake intensity rapid assessment methods(i.e.WFM,BPM and ASM) to evaluate the intensity of this earthquake.Then,we comparatively analyzed the three methods based on strong ground motion observation data and actual intensity maps.The results show that:(1) The earthquake is associated with a southeast-oriented single-sided rupture.The WFM method can only evaluate earthquakes with two-sided ruptures,which has some limitations;(2) The intensity of BPM and ASM was overestimated on the southwest and north sides of the epicenter,but other high-intensity zones were similar to the intensities measured by actual surveys;(3) The residuals of the three intensity assessment methods were all between-0.5 and 1.Although a small number of stations were underestimated,the overall residuals were good,and the residuals gradually approached 0 with the increase of distance;(4) The number of towns and villages evaluated by the three methods in the earthquake area was almost all lower than the field survey results.One exception is the area of Ⅷ degree,where the BPM and ASM were higher than the survey results;(5) The area of the earthquake area evaluated by the three methods was low in Ⅵ and Ⅶ degree,moderate in Ⅷ degree,and low in Ⅸ degree(the area from ASM is similar to the area measured by actual survey).Overall,ASM is applicable to this earthquake intensity assessment. 展开更多
关键词 Luding earthquake Seismic intensity Rapid assessment Ground-Motion prediction equation BACK-PROJECTION AFTERSHOCK
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Water resource utilization characteristics and driving factors in the Hainan Island
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作者 dun wang Li-xin Pei +3 位作者 Li-zhong Zhang Xi-wen Li Ze-heng Chen Yue-hu Zhou 《Journal of Groundwater Science and Engineering》 2023年第2期191-206,共16页
The scarcity of water resources caused by the unique topography and uneven rainfall distribution in Hainan Island has become a major factor restricting local development. In order to provide effective and scientific r... The scarcity of water resources caused by the unique topography and uneven rainfall distribution in Hainan Island has become a major factor restricting local development. In order to provide effective and scientific reference basis for the overall water resource utilization status and solving this problem, this study calculated the water resource utilization situation of Hainan Island from 2017 to 2021 in detail using methods including water resource ecological footprint analysis. Furthermore, a spatial correlation analysis was conducted to examine the island's water resource utilization characteristics, and the driving factors behind the changes in water resource utilization over the past five years were analyzed using the LMDI model. The results show that:(1) During the study period, the water resource ecological footprint in Hainan Island exhibited a slow growth trend, while the ecological carrying capacity showed a downward tendency.The per capita ecological deficit of water resources remains relatively high, and the water consumption per 10 000 yuan GDP in the whole land continues to decrease, indicating that the overall pressure on water resource demand remains high with significant regional differences accompanied by the efficiency of water resource utilization steadily improving at the same time;(2) Agricultural water use accounts for the highest proportion in the entire water use structure, while ecological water use represents the smallest share, with a year-on-year increase, indicating that Hainan Island highlights the agricultural development and is increasingly conscious of the ecological environment;(3) Significant spatial differentiation in water resource utilization characteristics exists in Hainan Island, with the western region being a hot spot aggregation area for per capita water resource ecological footprint, per capita ecological carrying capacity of water resources, water consumption per 10 000 yuan GDP, while it is a cold spot cluster area for per capita ecological deficit of water resources. The opposite holds true for the eastern region of Hainan Island;(4) Economic and technological factors have a major impact on the changes in water resource ecological footprint within the designated area. Among them, economic factors drive the growth of the water resource ecological footprint in Hainan Island, and exacerbate local water resource consumption, while technological factors negatively contribute to the amount of water resource utilization in Hainan Island, indicating that advanced technology has improved water resource utilization efficiency and significantly reduced water resource consumption. 展开更多
关键词 Ecological footprint Ecological carrying capacity Water consumption Moran'sⅠindex Cold/hot spot analysis LMDI model
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Rapid report of the 8 January 2022 M_(S)6.9 Menyuan earthquake,Qinghai,China 被引量:25
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作者 Hongfeng Yang dun wang +7 位作者 Rumeng Guo Mengyu Xie Yang Zang Yue wang Qiang Yao Chuang Cheng Yanru An Yingying Zhang 《Earthquake Research Advances》 CSCD 2022年第1期4-14,共11页
The M_(S)6.9 Menyuan earthquake in Qinghai Province,west China is the largest earthquake by far in 2022.The earthquake occurs in a tectonically active region,with a background b-value of 0.87 within 100 km of the epic... The M_(S)6.9 Menyuan earthquake in Qinghai Province,west China is the largest earthquake by far in 2022.The earthquake occurs in a tectonically active region,with a background b-value of 0.87 within 100 km of the epicenter that we derived from the unified catalog produced by China Earthquake Networks Center since late 2008.Field surveys have revealed surface ruptures extending 22 km along strike,with a maximum ground displacement of 2.1 m.We construct a finite fault model with constraints from In SAR observations,which showed multiple fault segments during the Menyuan earthquake.The major slip asperity is confined within 10 km at depth,with the maximum slip of 3.5 m.Near real-time back-projection results of coseismic radiation indicate a northwest propagating rupture that lasted for~10 s.Intensity estimates from the back-projection results show up to a Mercalli scale of IX near the ruptured area,consistent with instrumental measurements and the observations from the field surveys.Aftershock locations(up to January 21,2022)exhibit two segments,extending to~20 km in depth.The largest one reaches M_(S)5.3,locating near the eastern end of the aftershock zone.Although the location and the approximate magnitude of the mainshock had been indicated by previous studies based on paleoearthquake records and seismic gap,as well as estimated stressing rate on faults,significant surfacebreaching rupture leads to severe damage of the high-speed railway system,which poses a challenge in accurately assessing earthquake hazards and risks,and thus demands further investigations of the rupture behaviors for crustal earthquakes. 展开更多
关键词 Surface rupture Coseismic slip Real-time Intensity Aftershock location and statistics Earthquake magnitude forecasting
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Ratiometric delivery of doxorubicin and berberine by liposome enables superior therapeutic index than Doxil? 被引量:4
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作者 Ruoshi Zhang Yingxi Zhang +7 位作者 Yue Zhang Xin wang Xuanming Gao Yuyan Liu Xuanbo Zhang Zhonggui He dun wang Yongjun wang 《Asian Journal of Pharmaceutical Sciences》 SCIE CAS 2020年第3期385-396,共12页
Although the appearance of Doxil alleviated the cardiotoxicity of DOX, the progression-free survival of patients was not prolonged compared with traditional medication regimens, and side effects such as hand-foot synd... Although the appearance of Doxil alleviated the cardiotoxicity of DOX, the progression-free survival of patients was not prolonged compared with traditional medication regimens, and side effects such as hand-foot syndrome has occurred. In order to solve this dilemma, we have designed a novel co-delivery strategy to construct a co-loaded liposome of berberine(BER) and doxorubicin(DOX), which was called Lipo Be Do. The optimal synergistic ratio of the two drugs was screened by cell cytotoxicity experiments in vitro, and the optimal attenuation ratio was further determined by in vivo cardiac H&E staining pathological sections. The optimal combination treatment caused a robust increase in apoptotic cells of 4T1, as compared to drug alone treatment. The prepared co-loaded liposome, Lipo Be Do, had high encapsulation efficiency and good stability. The nanoliposome carrier controlled the biological fate of the drugs and maintained a pre-defined optimal ratio in vivo. The Lipo Be Do significantly inhibited tumor growth in 4T1 murine mammary carcinoma model compared with Doxil(P < 0.05), and completely overcame the myocardial rupture toxicity caused by Doxil in mice. Our co-loaded liposome delivery platform technology provided a new direction for the clinical treatment of triple-negative breast cancer and the safe application of DOX. 展开更多
关键词 BERBERINE DOXORUBICIN NANOLIPOSOMES Remote loading Combination therapy Cardiotoxity
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Co-amorphous solid dispersion systems of lacidipine-spironolactone with improved dissolution rate and enhanced physical stability 被引量:2
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作者 Zhaomeng wang Mengchi Sun +7 位作者 Tian Liu Zisen Gao Qing Ye Xiao Tan Yanxian Hou Jin Sun dun wang Zhonggui He 《Asian Journal of Pharmaceutical Sciences》 SCIE 2019年第1期95-103,共9页
Co-amorphous solid dispersion(C-ASD)systems have attracted great attention to improve the solubility of poorly soluble drugs,but the selection of an appropriate stabilizer to stabilize amorphous forms is still a huge ... Co-amorphous solid dispersion(C-ASD)systems have attracted great attention to improve the solubility of poorly soluble drugs,but the selection of an appropriate stabilizer to stabilize amorphous forms is still a huge challenge.Herein,C-ASD system of two clinical combined used drugs(lacidipine(LCDP)and spironolactone(SPL))as stabilizers to each other,was prepared by solvent evaporation method.The effects of variation in molar ratio of LCDP and SPL(3:1,1:1,1:3,1:6,and 1:9)on the drug release characteristics were explored.Polarized light microscopy(PLM),powder X-ray diffraction(PXRD),differential scanning calorimetry(DSC)and thermogravimetric analysis(TGA)were employed to evaluate the solid states.Prepared C-ASDs were further studied for their stability under the high humidity(RH 92.5%).Further analysis of C-ASDs via Fourier-transform infrared spectroscopy(FTIR)and Raman spectroscopy confirmed that hydrogen bond interactions between the two drugs played a significant role in maintaining the stability of the C-ASDs systems.Moreover,molecular dynamic(MD)simulations provided a clear insight into the stability mechanism at the molecular level.This study demonstrated the novel drug-drug C-ASDs systems is a promising formulation strategy for improved dissolution rate and enhanced physical stability of poorly soluble drugs. 展开更多
关键词 Co-amorphous solid DISPERSION LACIDIPINE SPIRONOLACTONE Stability Molecular dynamic(MD) simulations
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Imaging the rupture process of the 10 January 2018 Mw7.5 Swan island, Honduras earthquake 被引量:1
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作者 Chuang Cheng dun wang 《Earthquake Science》 2020年第4期194-200,共7页
The 10 January 2018 Mw7.5 Swan island,Honduras earthquake occurred on the Swan island fault,which is a transform plate boundary between the North American and Caribbean plates.Here we back-project the rupture process ... The 10 January 2018 Mw7.5 Swan island,Honduras earthquake occurred on the Swan island fault,which is a transform plate boundary between the North American and Caribbean plates.Here we back-project the rupture process of the earthquake using dense seismic stations in Alaska,and find that the earthquake ruptured at least three faults(three stages)for a duration of~40 s.The rupture speed for the longest fault(stage 3)is as fast as 5 km/s,which is much faster than the local shear wave velocity of~4 km/s.Supershear rupture was incidentally observed on long and straight strike-slip faults.This study shows a supershear rupture that occured on a strike-slip fault with moderate length,implying that supershear rupture might commonly occur on large strike-slip earthquakes.The common occurrence of supershear rupture on strike-slip earthquakes will challenge present understanding of crack physics,as well as strong ground motion evaluation in earthquake engineering. 展开更多
关键词 2018 Mw7.5 Honduras earthquake source process BACK-PROJECTION rupture speed supershear rupture
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使用欧洲、中国、日本和澳大利亚4个台阵由反投影方法确定的2015年4月25日尼泊尔M_W7.8地震的短周期能量 被引量:5
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作者 dun wang Jim Mori 杨国栋 《国际地震动态》 2016年第5期9-18,共10页
应用反投影(backprojection)分析方法确定了2015年尼泊尔地震产生的短周期(0.5~5s)能量的震源位置和时间。使用欧洲、中国、日本和澳大利亚不同方位的不同台阵的数据,这些数据在破裂传播方面表现出一致的特性。发震后的25~55s,强短... 应用反投影(backprojection)分析方法确定了2015年尼泊尔地震产生的短周期(0.5~5s)能量的震源位置和时间。使用欧洲、中国、日本和澳大利亚不同方位的不同台阵的数据,这些数据在破裂传播方面表现出一致的特性。发震后的25~55s,强短周期能量震源分布在震中以东10~100km内。前20s破裂速度约1.0km/s,而在其后的30~40s加速到~3.0km/s。短周期能量震源位置接近于断层下倾边缘,它补充了更靠上发生的大断裂滑动区域。尼泊尔地震可能是大断层滑动区域与短周期能量震源区域不一致的另一个实例,这可能与破坏性强地震动有关。在线材料:使用4个不同台阵对尼泊尔地震进行反投影的动画演示。 展开更多
关键词 反投影 台阵 M_W7.8 震源位置 破裂速度 断层滑动 破裂传播 动画演示 区域边界 波形记录
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Synthesis and Bronchodilatory Activities of New Pyrazolo[4,3-d]pyrimidin-7-ones
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作者 dun wang Yan Fang ZHAO +1 位作者 De Sheng YU Ping GONG 《Chinese Chemical Letters》 SCIE CAS CSCD 2003年第12期1223-1226,共4页
Twelve novel pyrazolo [4,3-d] pyrimidin-7-ones were synthesized and their structures were confirmed by IR, 1H NMR and MS. Their in vitro bronchodilatory activities were tested in guinea-pigs. The pharmacological res... Twelve novel pyrazolo [4,3-d] pyrimidin-7-ones were synthesized and their structures were confirmed by IR, 1H NMR and MS. Their in vitro bronchodilatory activities were tested in guinea-pigs. The pharmacological results show that compound 11c has more potent activity than aminophylline. 展开更多
关键词 Pyrazolo [4 3-d] pyrimidin-7-ones SYNTHESIS bronchodilatory activity.
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Synthesis and Vasodilatory Activities of New Pyrazolo[3,4-d] pyrimidin-4-one Derivatives
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作者 Ping GONG Yan Fang ZHAO dun wang 《Chinese Chemical Letters》 SCIE CAS CSCD 2002年第7期613-616,共4页
A series of pyrazolo[3,4-d]pyrimidin-4-one derivatives were synthesized and tested for vasodilatory activities. All of them were new compounds and their structures were confirmed by IR, 1H NMR, MS and elemental analy... A series of pyrazolo[3,4-d]pyrimidin-4-one derivatives were synthesized and tested for vasodilatory activities. All of them were new compounds and their structures were confirmed by IR, 1H NMR, MS and elemental analysis. 展开更多
关键词 Pyrazolo [3 4-d] pyrimidin-4-ones SYNTHESIS vasodilatory activity.
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Campus Vibration in Nanwangshan Campus,China University of Geosciences at Wuhan Monitored by Short-Period Seismometers 被引量:5
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作者 Lihui Wu dun wang +4 位作者 Ziguang Lei Jing Fu Shuai Min Xianbing Xu Sarina Bao 《Journal of Earth Science》 SCIE CAS CSCD 2020年第5期950-956,共7页
Continuous seismic observations can record seismic waveforms, and ambient noise, for the purposes of earthquake researches and other applications. Here we deploy three digital seismometers(EPS-2) in and around the Nan... Continuous seismic observations can record seismic waveforms, and ambient noise, for the purposes of earthquake researches and other applications. Here we deploy three digital seismometers(EPS-2) in and around the Nanwangshan Campus of the China University of Geosciences(Wuhan). This network was running from April 9 to May 9 of 2018. During this period, the seismometers recorded the May 4, 2018 M6.9 Hawaii earthquake. From the recorded waveforms, we could observe clearly the P and S arrivals, and the corresponding particle motions. Analysis of continuous observations of ambient noise shows obvious fluctuation of vibration intensity inside of the campus. The campus is quietest from 0 to 5 am. From 5 am on, the vibration intensity increases, and reaches the peak of entire day at 12 am. The amplitude then decreases to a very low level at 19:30 to 20:00 pm, and reaches another strong noisy time at 21:00 to 21:30 pm. After 21:30 pm, the intensity goes down slowly. We also observed seismic signals that were generated by the interaction of speed-control hump cars and ground. By taking the envelope and smooth operations, we observe different characteristics for different car speeds, which suggests that seismic monitoring approaches can be used for speed measurement of cars. This kind of small seismic network running in a real time fashion, would greatly help understanding of the sources of ambient noise at high frequency bands in interested areas. Analysis of a long-term observed dataset, and real time illustration will help to strengthen campus security and high-precision laboratory deployments, and also contribute to research atmosphere in earthquake science. 展开更多
关键词 ambient noise vibration intensity seismic waves SEISMOMETERS human activity
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Early Report of the Source Characteristics,Ground Motions,and Casualty Estimates of the 2023 Mw 7.8 and 7.5 Turkey Earthquakes 被引量:10
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作者 Wenkai Chen Gang Rao +2 位作者 Dengjie Kang Zhifan Wan dun wang 《Journal of Earth Science》 SCIE CAS CSCD 2023年第2期297-303,共7页
INTRODUCTION,At 01:17 UTC(04:17 on local time)on Feb.6,2023,a devastating earthquake with a moment magnitude(Mw)7.8 occurred in the Gaziantep,southern Turkey.The earthquake was located at 37.174°N and 37.032°... INTRODUCTION,At 01:17 UTC(04:17 on local time)on Feb.6,2023,a devastating earthquake with a moment magnitude(Mw)7.8 occurred in the Gaziantep,southern Turkey.The earthquake was located at 37.174°N and 37.032°E,with a hypocentral depth of 17.9 km as reported by the United States Geological Survey(USGS). 展开更多
关键词 EARTHQUAKE MAGNITUDE EARTHQUAKE
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Computer-aided recognition and assessment of a porous bioelastomer in ultrasound images for regenerative medicine applications
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作者 dun wang Sheng Yang +5 位作者 Kai-Xuan Guo Yan-Ying Zhu Jia Sun Aliona Dreglea Yan-Hong Gao Jiao Yu 《Medicine in Novel Technology and Devices》 2023年第3期41-52,共12页
It is difficult to use a single edge operator in image processing to extract continuous and accurate contours of a porous bioelastomer due to the fuzzy boundary and complex background in ultrasound images.To solve thi... It is difficult to use a single edge operator in image processing to extract continuous and accurate contours of a porous bioelastomer due to the fuzzy boundary and complex background in ultrasound images.To solve this problem,this paper proposes a joint algorithm for bioelastomer contour detection and a texture feature extraction method for monitoring the degradation performance of bioelastomers.First,the mean-shift clustering method is utilized to obtain the clustering feature information of bioelastomers and native tissue from manually segmented images,and this information is used as the initial information in the image binarization algorithm for image partitioning.Second,Otsu's thresholding method and mathematical morphology are applied in the process of image binarization.Finally,the Canny edge detector is employed to extract the complete bioelastomers contour from the binary image.To verify the robustness of the proposed joint algorithm,the results using the proposed joint algorithm,where mean-shift clustering is replaced with k-means clustering are also obtained.The proposed joint algorithm based on mean-shift clustering outperforms the joint algorithm based on k-means clustering,as well as algorithms that directly apply the Canny,Sobel and Laplacian methods.Texture feature extraction is based on the computer-aided recognition of bioelastomers.The region of interest(ROI)is set in the scaffold region,and the first-order statistical features and second-order statistical features of the greyscale values of the ROI are extracted and analysed.The proposed joint algorithm can not only extract ideal bioelastomers contours from ultrasound images but also provide valuable feedback on the degradation behaviour of bioelastomers at implant sites. 展开更多
关键词 Ultrasound imaging Computer-aided recognition Tissue repair Bioelastomers
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Estimating Seismic Intensity Maps of the 2021 Mw 7.3 Madoi,Qinghai and Mw 6.1 Yangbi,Yunnan,China Earthquakes 被引量:11
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作者 Wenkai Chen dun wang +2 位作者 Can Zhang Qiang Yao Hongjun Si 《Journal of Earth Science》 SCIE CAS CSCD 2022年第4期839-846,共8页
This study focuses on rapidly determining seismic intensity maps of earthquakes because it offers fundamental information for effective emergency rescue and subsequent scientific research,and remains challenging to ac... This study focuses on rapidly determining seismic intensity maps of earthquakes because it offers fundamental information for effective emergency rescue and subsequent scientific research,and remains challenging to accurately determine seismic intensity map in regions with sparse instrumental observations.Here we applied a novel method that consisted of array technology(backprojection),ground-motion prediction equations,and site corrections,to estimate the seismic intensity maps of the 2021 Mw 7.3 Madoi,Qinghai and the Mw 6.1 Yangbi,Yunnan,China earthquakes.We used seismic data recorded at European stations to back-project the source processes of the 2021 Mw7.3 Madoi,Qinghai and the Mw 6.1 Yangbi,Yunnan,China earthquakes.The back-projected energy radiations were then used as subevents or used to define the fault geometry.Summing the contributions of each subevent or estimating the shortest distances from each site to the rupture fault,we obtained the ground motion(PGA and PGV)for each site under rock site conditions.The estimated ground motions were corrected at each site for local site amplification according to the Vs30 database.Our estimated seismic intensity maps and field reports showed high similarity,which further validated the effectiveness of the novel approach,and pushed the limit of earthquake size down to~M 6.Such efforts would substantially help in the fast and accurate evaluation of earthquake damage,and precise rescue efforts. 展开更多
关键词 EARTHQUAKES seismic intensity map BACK-PROJECTION ground-motion prediction equations
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Lipophorin receptor regulates the cuticular hydrocarbon accumulation and adult fecundity of the pea aphid Acyrthosiphon pisum 被引量:4
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作者 Jian-Wen Qiao Yong-Liang Fan +4 位作者 Tian-Tian Bai Bing-Jin Wu Xiao-Jin Pei dun wang Tong-Xian Liu 《Insect Science》 SCIE CAS CSCD 2021年第4期1018-1032,共15页
Cuticular hydrocarbons form a barrier that protects terrestrial insects from water loss via the epicuticle.Lipophorin loads and transports lipids,including hydrocarbons,from one tissue to another.In some insects,the l... Cuticular hydrocarbons form a barrier that protects terrestrial insects from water loss via the epicuticle.Lipophorin loads and transports lipids,including hydrocarbons,from one tissue to another.In some insects,the lipophorin receptor(LpR),which binds to lipophorin and accepts its lipid cargo,is essential for female fecundity because it mediates the incorporation of lipophorin by developing oocytes.However,it is unclear whether LpR is involved in the accumulation of cuticular hydrocarbons and its precise role in aphid reproduction remains unknown.We herein present the results of our molecular characterization,phylogenetic analysis,and functional annotation of the pea aphid(Acyrthosiphon pisum)LpR gene(ApLpR).This gene was transcribed throughout the A.pisum life cycle,but especially during the embryonic stage and in the abdominal cuticle.Furthermore,we optimized the RHA interference(RNAi)parameters by determining the ideal dose and duration for gene silencing in the pea aphid.We observed that the RNAi-based ApLpR suppression significantly decreased the internal and cuticular hydrocarbon contents as well as adult fecundity.Additionally,a deficiency in cuticular hydrocarbons increased the susceptibility of aphids to desiccation stress,with decreased survival rates under simulated drought conditions.Moreover,ApLpR expression levels significantly increased in response to the desiccation treatment.These results confirm that ApLpR is involved in transporting hydrocarbons and protecting aphids from desiccation stress.Furthermore,this gene is vital for aphid reproduction.Therefore,the ApLpR gene of A.pisum may be a novel RNAi target relevant for insect pest management. 展开更多
关键词 desiccation resistance FECUNDITY HYDROCARBON lipophorin receptor pea aphid
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Paleo-Earthquakes along the Zheduotang Fault,Xianshuihe Fault System,Eastern Tibet:Implications for Seismic Hazard Evaluation 被引量:3
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作者 Guifan Chen Mervin Bartholomew +3 位作者 Demin Liu Kai Cao Minxuan Feng dun wang 《Journal of Earth Science》 SCIE CAS CSCD 2022年第5期1233-1245,共13页
The Kangding City in eastern Tibet is at high risk due to frequent strong earthquakes along the Xianshuihe sinistral strike-slip fault bounding the Chuandian Block to the northeast.The knowledge of paleo-seismicity re... The Kangding City in eastern Tibet is at high risk due to frequent strong earthquakes along the Xianshuihe sinistral strike-slip fault bounding the Chuandian Block to the northeast.The knowledge of paleo-seismicity recurrence along this fault system is key to the evaluation of earthquake hazards in this region;thus,more accurate paleoseismic information are required.We examined the paleo-seismicity along the Zheduotang fault in the central segment of the Xianshuihe fault system by applying the field investigation,trenching,and Quaternary dating methods(e.g.,OSL and ^(14)C).Field observations found~8.5 m offset of stream by sinistral slip along the Zheduotang fault.We trenched the central fault zone of the Zheduotang fault and found that the colluvial wedges and five buried,discontinuous,A-soil horizons progressively have been offset in the shallow graben on the SW-side of the main fault indicative of the paleo-earthquakes.The dating results of OSL and ^(14)C,in line with existing data,enable us to establish the paleo-seismic history of the Zheduotang fault.It shows at least eight surface ruptures in the last 7500 years identified from displaced buried soils,colluvial wedges and terraces.Our study reveals~100 years minimum paleo-earthquake recurrence,suggesting potential large earthquakes in the Kangding area in the future. 展开更多
关键词 Tibetan Plateau Xianshuihe fault system paleo-seismicity TRENCH RECURRENCE GEOPHYSICS
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Magnitude of the 23 January 2018 M7.9 Alaska Earthquake Estimated from Local Dense Seismic Records in Alaska 被引量:2
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作者 Chen Song Qiang Yao dun wang 《Journal of Earth Science》 SCIE CAS CSCD 2019年第5期1005-1009,共5页
We apply a novel method to estimate the magnitude of the 23 January 2018 M7.9 Alaska earthquake using seismic stations recorded at local to regional distances in Alaska, US. We determine the source duration from back-... We apply a novel method to estimate the magnitude of the 23 January 2018 M7.9 Alaska earthquake using seismic stations recorded at local to regional distances in Alaska, US. We determine the source duration from back-projection results derived from the Alaska stations in a relatively compact azimuth range. Then we calculate the maximum P-wave displacements recorded on a wide azimuth range at distances of 8 to 15 degrees. Combining the source duration and the maximum P-wave displacements, we obtain magnitudes of 7.86–8.03 for the 23 January 2018 earthquake in 3–5 min, very close to the Mw 7.9 determined by the USGS and GCMT. This example validates the new approach for determining magnitude of large earthquakes using local to regional stations, and its time efficiency that magnitudes of large earthquakes can be accurately estimated within in 3–5 min after origin time. Therefore, further application of this new method would help accurate estimation of size of earthquakes that occur offshore and might cause tsunami hazards. 展开更多
关键词 rapid MAGNITUDE estimation BACK-PROJECTION real-time SEISMOLOGY TSUNAMI WARNING GEOPHYSICS
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Synthesis of tetrazole containing 1,2,3-thiadiazole derivatives via U-4CR and their anti-TMV activity 被引量:3
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作者 Shou-Xin wanga Zhen Fang +8 位作者 Zhi-Jin Fan dun wang Yue-Dong Li Xiao-Tian Ji Xue-Wen Hua Yun Huang Tatiana A.Kalinina Vasiliy A.Bakulev Yury Yu.Morzherin 《Chinese Chemical Letters》 SCIE CAS CSCD 2013年第10期889-892,共4页
A series of novel tetrazole containing 1,2,3-thiadiazole derivatives were designed and synthesized via Ugi reaction. Their structures were confirmed by melting points, IR, 1H NMR, and HRMS (ESI). Preliminary bioassa... A series of novel tetrazole containing 1,2,3-thiadiazole derivatives were designed and synthesized via Ugi reaction. Their structures were confirmed by melting points, IR, 1H NMR, and HRMS (ESI). Preliminary bioassay indicated that most target compounds exhibited very good direct anti-TMV activity at 100 μg/mL, which was equal to or higher than that of ribavirin. Among them, compounds 4b, 4c and 4i also showed equivalent protection effect to ribavirin in vivo at 100 μg/mL. 展开更多
关键词 1 2 3-Thiadiazole Tetrazole Anti-TMV activity Ugi reaction
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Advances in BeiDou Navigation Satellite System(BDS)and satellite navigation augmentation technologies 被引量:14
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作者 Rui Li Shuaiyong Zheng +4 位作者 Ershen wang Jinping Chen Shaojun Feng dun wang Liwen Dai 《Satellite Navigation》 2020年第1期126-148,共23页
Several noteworthy breakthroughs have been made with the BeiDou Navigation Satellite System(BDS)and other global navigation satellite systems as well as the associated augmentation systems,such as the commissioning of... Several noteworthy breakthroughs have been made with the BeiDou Navigation Satellite System(BDS)and other global navigation satellite systems as well as the associated augmentation systems,such as the commissioning of the BDS-3 preliminary system and the successful launch of the first BDS-3 GEO satellite which carries the satellite-based augmentation payload.Presently,BDS can provide basic services globally,and its augmentation system is also being tested.This paper gives an overview of BDS and satellite navigation augmentation technologies.This overview is divided into four parts,which include the system segment technologies,satellite segment technologies,propagation segment technologies,and user segment technologies.In each part,these technologies are described from the perspectives of preliminary information,research progress,and summary.Moreover,the significance and progress of the BeiDou Satellite-based Augmentation System(BDSBAS),low earth orbit augmentation,and the national BeiDou ground-based augmentation system are presented,along with the airborne-based augmentation system.Furthermore,the conclusions and discussions covering popular topics for research,frontiers in research and development,achievements,and suggestions are listed for future research. 展开更多
关键词 BeiDou Navigation Satellite System Satellite navigation augmentation systems System segment technologies Satellite segment technologies Propagation segment technologies User segment technologies
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Recombinant Helicoverpa armigera nucleopolyhedrovirus with arthropod-specific neurotoxin gene RjAa 17f from Rhopalurus junceus enhances the virulence against the host larvae 被引量:2
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作者 Huan Yu Bin Zhou +3 位作者 Jiao Meng Jian Xu Tong-Xian Liu dun wang 《Insect Science》 SCIE CAS CSCD 2017年第3期397-408,共12页
A recombinant Helicoverpa armigera nucleopolyhedrovirus (HearNPV) ex- pressing the insect-selective neurotoxin (RjAalTjO from Cuban scorpion Rhopalurus junceus was constructed by replacing the UDP-glucosyltransfera... A recombinant Helicoverpa armigera nucleopolyhedrovirus (HearNPV) ex- pressing the insect-selective neurotoxin (RjAalTjO from Cuban scorpion Rhopalurus junceus was constructed by replacing the UDP-glucosyltransferase gene (egt) using )^- red homologous recombination system. Another egt deleted control HearNPV was con- structed in a similar way by inserting egfp gene into the egt locus. One-step viral growth curve and viral DNA replication curve analysis confirmed that the recombination did not affect the viral growth and DNA replication in host cells. There is no discernable differ- ence in occlusion-body morphogenesis between RjAalTf-HearNPV,, Egfp-HearNPV and HZ8-HearNPV, which was confirmed by transmission electron microscopy analysis. How- ever, the insecticidal activity of RjAal 7f-HearNPV is enhanced against the third instar H. armigera larvae according to the bioassay on virulence comparison. There is a dramatic reduction (56.9%) in median lethal dose (LD50) and also a reduction (13.4%) in median sur- vival time (ST50) for the recombinant RjAalTf-HearNPV compared to the HZ8-HearNPV, but only a 27.5% reduction in LD50 and 10.1% reduction in ST50 value when Egfp- HearNPV is compared with HZ8-HearNPV. The daily diet consumption analysis showed that the RjAal 7f-HearNPV was able to inhibit the infected larvae feeding compared with the egt minus HearNPV. These results demonstrated that this novel recombinant RjAa17f- HearNPV could improve the insecticidal effect against its host insects and RjAa17fcould be a considerable candidate for other recombinant baculovirus constructions. 展开更多
关键词 HEARNPV recombinant baculovirus RjAal 7f virulence improvement
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