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12018 Chinese Pediatric Cardiology Society(CPCS) guideline for diagnosis and treatment of syncope in children and adolescents显示文摘Syncope belongs to the transient loss of consciousness(TLOC), characterized by a rapid onset, short duration, and spontaneous complete recovery. It is common in children and adolescents, accounting for 1% to 2% of emergency department visits.Recurrent syncope can seriously affect children's physical and mental health, learning ability and quality of life and sometimes cardiac syncope even poses a risk of sudden death. The present guideline for the diagnosis and treatment of syncope in children and adolescents was developed for guiding a better clinical management of pediatric syncope. Based on the globally recent development and the evidence-based data in China, 2018 Chinese Pediatric Cardiology Society(CPCS) guideline for diagnosis and treatment of syncope in children and adolescents was jointly prepared by the Pediatric Cardiology Society, Chinese Pediatric Society, Chinese Medical Association(CMA)/Committee on Pediatric Syncope, Pediatricians Branch, Chinese Medical Doctor Association(CMDA)/Committee on Pediatric Cardiology, Chinese College of Cardiovascular Physicians, Chinese Medical Doctor Association(CMDA)/Pediatric Cardiology Society, Beijing Pediatric Society, Beijing Medical Association(BMA). The present guideline includes the underlying diseases of syncope in children and adolescents, the diagnostic procedures, methodology and clinical significance of standing test and headup tilt test, the clinical diagnosis vasovagal syncope, postural orthostatic tachycardia syndrome, orthostatic hypotension and orthostatic hypertension, and the treatment of syncope as well as follow-up.Cheng Wang Yaqi Li Ying Liao Hong Tian Min Huang Xiangyu Dong Lin Shi Jinghui Sun Hongfang Jin Junbao Du Jindou An Jie Chen Mingwu Chen Qi Chen Sun Chen Yonghong Chen Zhi Chen Adolphus Kai-tung Chau Junbao Du Zhongdong Du Junkai Duan Hongyu Duan Xiangyu Dong Lin Feng Lijun Fu Fangqi Gong Yonghao Gui Ling Han Zhenhui Han Bing He Zhixu He Xiufen Hu Yimin Hua Guoying Huang Min Huang Ping Huang Yujuan Huang Hongfang Jin Mei Jin Bo Li Fen Li Tao Li Xiaohui Li Xiaoyan Liu Yan Li Haitao Lv Tiewei Lv Zipu Li Luyi Ma Silin Pan Yusheng Pang Hua Peng Yuming Qin Jie Shen Lin Shi Kun Sun Jinghui Sun Hong Tian Jie Tian Cheng Wang Hong Wang Lei Wang Jinju Wang Wendi Wang Yuli Wang Rongzhou Wu Tianhe Xia Yanyan Xiao Chunhong Xie Yanlin Xing Zhenyu Xiong Baoyuan Xu Yi Xu Hui Yan Shiwei Yang Qijian Yi Xia Yu Xianyi Yu Yue Yuan Hongyan Zhang Huili Zhang Li Zhang Qingyou Zhang Xi Zhang Yanmin Zhang Zhiwei Zhang Cuifen Zhao Bin Zhou Hua Zhu 2018Science Bulletin2018,63,23:54
2Removal characteristics of microplastics by Fe-based coagulants during drinking water treatment显示文摘Microplastics have caused great concern worldwide recently due to their ubiquitous presence within the marine environment. Up to now, most attention has been paid to their sources,distributions, measurement methods, and especially their eco-toxicological effects. With microplastics being increasingly detected in freshwater, it is urgently necessary to evaluate their behaviors during coagulation and ultrafiltration(UF) processes. Herein, the removal behavior of polyethylene(PE), which is easily suspended in water and is the main component of microplastics, was investigated with commonly used Fe-based salts. Results showed that although higher removal efficiency was induced for smaller PE particles, low PE removal efficiency(below 15%) was observed using the traditional coagulation process, and was little influenced by water characteristics. In comparison to solution pH, PAM addition played a more important role in increasing the removal efficiency, especially anionic PAM at high dosage(with efficiency up to 90.9%). The main reason was ascribed to the dense floc formation and high adsorption ability because of the positively charged Fe-based flocs under neutral conditions. For ultrafiltration, although PE particles could be completely rejected,slight membrane fouling was caused owing to their large particle size. The membrane flux decreased after coagulation; however, the membrane fouling was less severe than that induced by flocs alone due to the heterogeneous nature of the cake layer caused by PE, even at high dosages of Fe-based salts. Based on the behavior exhibited during coagulation and ultrafiltration, we believe these findings will have potential application in drinking water treatment.Baiwen Ma Wenjing Xue Yanyan Ding Chengzhi Hu Huijuan Liu Jiuhui Qu 2019Journal of Environmental Sciences2019,31,4:29
3Osthole inhibits proliferation of human breast cancer cells by inducing cell cycle arrest and apoptosis显示文摘Recent studies have revealed that osthole,an active constituent isolated from the fruit of Cnidium monnieri(L.) Cusson,a traditional Chinese medicine,possesses anticancer activity.However,its effect on breast cancer cells so far has not been elucidated clearly.In the present study,we evaluated the effects of osthole on the proliferation,cell cycle and apoptosis of human breast cancer cells MDA-MB 435.We demonstrated that osthole is effective in inhibiting the proliferation of MDA-MB 435 cells,The mitochondrion-mediated apoptotic pathway was involved in apoptosis induced by osthole,as indicated by activation of caspase-9 and caspase-3 followed by PARP degradation.The mechanism underlying its effect on the induction of G1 phase arrest was due to the up-regulation of p53 and p21 and down-regulation of Cdk2 and cyclin D1 expression.Were observed taken together,these findings suggest that the anticancer efficacy of osthole is mediated via induction of cell cycle arrest and apoptosis in human breast cancer cells and osthole may be a potential chemotherapeutic agent against human breast cancer.Lintao Wang Yanyan Peng Kaikai Shi Haixiao Wang Jianlei Lu Yanli Li Changyan Ma 2015The Journal of Biomedical Research2015,29,2:12
4Direct differentiation of atrial and ventricular myocytes from human embryonic stem cells by alternating retinoid signals显示文摘尽管 myocyte 房间移植研究为心肌的梗塞建议了一个有希望的治疗学的潜力,到为心肌的修理的临床的治疗的发展的一个主要障碍是与为移植获得相对同类的室的 myocytes 联系的困难。人的胚胎的干细胞(hESCs ) 是 cardiomyocytes 的有希望的来源。这里,我们报导发信号的 retinoid 在 hESCs 的心脏的区别期间调整 atrial 对室的 myocytes 的命运说明。我们发现少量和 pan-retinoic 酸受体对手 BMS-189453 (RAi ) 显著地增加了 hESCs 的心脏的区别效率。为了调查 retinoid,工作,我们把对待 Noggin+RAi 的文化与对待 Noggin+RA 的文化作比较。我们的结果证明室特定的基因 IRX-4 的表示层次极端地在对待 Noggin+RAi 的文化被提高。MLC-2V,另一个室特定的标记,在对待 Noggin+RAi 的文化,然而并非在对待 Noggin+RA 的文化的 cardiomyocytes 在 cardiomyocytes 的多数被表示。流动 cytometry 分析和 electrophysiological 研究与 64.7Qiangzhe Zhang Junjie Jiang Pengcheng Han Qi Yuan Jing Zhang Xiaoqian Zhang Yanyan Xu Henghua Cao Qingzhang Meng Li Chen Tian Tian Xin Wang Pu Li Jurgen Hescheler Guangju Ji Yue Ma 2011Cell Research2011,21,4:10
5Early evaluation of growth traits of Larix kaempferi clones显示文摘Early selection is an important method to shorten the breeding cycle for tree species, which may differ in the time for early selection.To evaluate the early selected time for Larix kaempferi, tree height and diameter at breast height of 57 L.kaempferi clones were measured over many different growth years.The results indicated that, except for age × clone interaction for diameter at breast height(P = 0.741), there were significant differences among all variation sources(P < 0.01).The coefficient of phenotypic variation ranged from 14.89 to 35.65%for height and from 19.17 to 23.86% for diameter at breast height in different growth years.The repeatability of height and of diameter at breast height among clones was high,ranging from 0.6181 to 0.8531(height) and from 0.8443 to0.8497(diameter at breast height), in different growth years.There were significant positive correlations between all pairs of growth traits except between height in the 2 nd growth year and height in the 30 th growth year; and between height in the 2 nd growth year × diameter at breast height in the 30 th growth year.With a comprehensive evaluation method and a selection ratio of 10%, L65,L1, L62, L9, L15, and L78 were selected as excellent clones in the 30 th growth year.Their average values of height and diameter at breast height were 9.81 and 16.57%higher than the overall average, representing genetic gains of 6.46 and 13.99%, respectively.This study provides a theoretical foundation for the genetic improvement of L.kaempferi.Yanyan Pan Shuchun Li Chenglu Wang Wenjun Ma Guiyou Xu Lili Shao Kailong Li Xiyang Zhao Tingbo Jiang 2018Journal of Forestry Research2018,29,4:10
6Effects of protein properties on ultrafiltration membrane fouling performance in water treatment显示文摘Protein-like substances always induce severe ultrafiltration(UF) membrane fouling. To systematically understand the effect of proteins, regenerated cellulose UF membrane(commonly used for protein separation) performance was investigated in the presence of bovine serum albumin(BSA) under various water conditions. Results showed that although trypsin enhanced the membrane flux via proteolysis, catalysis took a long time. Membrane fouling was alleviated at high solution p H and low water temperature owing to the strong electrostatic repulsion force among BSA molecules. Both Na^+ and Ca^(2+)could increase membrane flux. However, Ca^(2+)played a bridging role between adjacent BSA molecules,whereas membrane fouling was alleviated via a hydration repulsion force with Na+. The order of influence on membrane fouling was as follows: Ca^(2+)concentration > Na+concentration > pH > temperature > trypsin concentration. Furthermore, a polyvinylidene fluoride UF membrane experiment showed that Ca^(2+)could reduce the fouling induced by BSA. Thus, the differences in UF membrane performance will have application potential for alleviating UF membrane fouling induced by proteins during water treatment.Yanyan Ding Baiwen Ma Huijuan Liu Jiuhui Qu 2019Journal of Environmental Sciences2019,31,3:9
7Primarily screening and analyzing ESTs differentially expressed in rats' primary liver cancer显示文摘Objective: To screen and analyze key express sequence tags (ESTs) which were differentially displayed in every period of SD rats' primary hepatic carcinoma and reveal the molecular mechanism of carcinogenesis. Methods: Using diethylnitrosamine (DENA) as a cancerigenic agent, animal models with different phases of primary hepatic cancer were constructed in SD rats. Rats were respectively sacrificed at d 14, d 28, d 56, d 77, d 105 and d 112 after the rats received DENA by gavage, then the livers were harvested. One part of the livers was classified according to their pathological changes, while the other was reserved for molecular mechanism studies on hepatocarcinogenesis. The differentially expressed genes were isolated from both normal and morbid tissues by mRNA differential display technique (DDRT-PCR). After the fragments were sequenced, bioinformatics were used to analyze the results. Results: Twelve differentially expressed cDNA fragments were obtained. Nine fragments had the homology with known cDNA clones, especially EST-7 was similar to BN/SsNHsdMCW mitochondrion gene and the identity was 100% which suggested EST-7 may be the part of BN/SsNHsdMCW mitochondrion gene. In contrast, other three fragments (EST-1, EST-3 and EST-5) had extremely low identity to any genes registered in GENBANK databases. Conclusions: BN/SsNHsdMCW mitochondrion gene was expressed in different periods of hepatocarcinogenesis. Moreover, EST-1, EST-3 and EST-5 were suggested to contribute to the development of rat hepatocarcinogenesis, and thus may be candidates of new targets of oncogenes or cancer suppressor genes.Dandan Liu Lijuan Zhi Mingxia Ma Dan Qiao Meijuan Wang Yawei Wang Baijie Jin Anqi Li Guting Liu Yiqing Zhang Yanyan Song Hongxu Zhang 2013Chinese Journal of Cancer Research2013,25,1:9
8Sea surface temperature record from the north of the East China Sea since late Holocene显示文摘Using the alkenone paleotemperature index U k 37′, a high-resolution sea surface temperature (SST) record since 3600 a BP was reconstructed from the mud area in the north of the East China Sea. Combining with the grain size distribution curve of sensitive grain size group, which may reflect the East Asia Winter Monsoon activity, the palaeoenvironmental evolution cycle throughout the late Holocene in the area was obtained. The marine environment evolution during the last 3600 years displays a five-stage trend. (1) Temperature descending period from 0.85 cal. ka BP to present. The maximum temperature decrease amplitude is 2℃. The winter monsoon intensified and ‘Little Ice Age’ were recorded in this period. (2) Warming period from 1.90 to 0.85 cal. ka BP. The mean temperature increase amplitude is 0.8℃. The Sui-Tang warming period was recorded at about 0.85―1.35 cal. ka BP and a prominent cooling event was recorded at 1.4 cal. ka BP in this period. (3) Temperature descending period from 2.55 to 1.90 cal. ka BP. Temperature cooling amplitude is 0.9℃. This period is coincident with an integrated temperature circle recorded in the Antarctic ice core, with the temperature changes from a slow cooling stage to a rapid warming stage. (4) Temperature comparatively stable with a little ascending period from 3.2 to 2.55 cal. ka BP. Temperature warming amplitude is 0.3℃. This period is coincident with the temperature fluctuant ascending period recorded in Antarctic ice core. (5) Temperature comparatively stable with little descending period from 3.6 to 3.2 cal. ka BP. This period corresponds with the temperature fluctuant cooling period recorded in Antarctic ice core. Basically, those five periods were coincident with the Antarctic ice core record. During the global cooling stage, the SST change in the continental shelf sea can be adjusted simultaneously.LI GuangXue SUN XiaoYan LIU Yong BICKERT Torsten MA YanYan 2009Chinese Science Bulletin2009,54,23:7
9Urotensin Ⅱ promotes monocyte chemoattractant protein-1 expression in aortic adventitial fibroblasts of rat显示文摘Zhang Yonggang Bao Shilin Kuang Zejian Ma Yanjun Hu Yanchao Mao Yanyan 2014Chinese Medical Journal2014,,10:7
10Studies on earthquake precursors in China:A review for recent 50 years显示文摘Since the 1960s,China has been conducting a persistent and systematic observation and monitoring experiment to falsify the hypothesis of premonitory anomalies and the predictability of earthquakes and the application of the assessment of time-dependent seismic hazard to the reduction of earthquake disaster risk.Such an endeavor,with cases of both successes and failures,provided lessons which are heuristic for the studies in earthquake science and social sustainability.This paper provides the background information of such an endeavor,discussing on the achievements and space for improvements of this long lasting and continuing effort.Fuqiong Huang Mei Li Yuchuan Ma Yanyan Han Lei Tian Wei Yan Xiaofan Li 2017Geodesy and Geodynamics2017,8,1:6
11Analysis of the ambiguity of log-constrained seismic impedance inversion显示文摘Although the ambiguity of seismic inversion is widely recognized in both theory and practice,so far as a concrete inversion example is concerned,there is not any objective,controllable method or any standard for how to evaluate and determine its ambiguity and reliability,especially for the high frequency components beyond the effective seismic frequency band.Taking log-constrained impedance inversion as an example,a new appraisal method is proposed on the basis of analyzing a simple geological model.Firstly,the inverted impedance model is transformed to a reflection coefficient series.Secondly,the maximum effective frequency of the real seismic data is chosen as a cutoff point and the reflection coefficient series is decomposed into two components by low-pass and high-pass filters.Thirdly,the geometrical reflection characteristics of the high-frequency components and that of the real seismic data are compared and analyzed.Then,the reliability of the inverted impedance model is appraised according to the similarity of geometrical characteristics between the high-frequency components and the real seismic data.The new method avoids some subjectivity in appraising the inverted result,and helps to enhance the reliability of reservoir prediction by impedance inversion technology.Li Guofa Li Hao Ma Yanyan Xiong Jinliang 2011Petroleum Science2011,8,2:5
12Exosomes with low miR-34c-3p expression promote invasion and migration of non-small cell lung cancer by upregulating integrinα2β1显示文摘Exosomes play critical roles in regulating various physiological and pathological processes,including immune stimulation,immune suppression,cardiovascular diseases,and cancers.Recent studies show that exosomes that transport specific microRNAs(miRNAs)are involved in tumor development.However,the molecular mechanism by which tumor invasion and migration are regulated by exosomes from non-small cell lung cancer(NSCLC)is not well understood.Here,we show that exosomes shuttling low levels of miR-34c-3p are involved in NSCLC progression.Our results showed that exosomes derived from NSCLC cells carrying low levels of miR-34c-3p could be transported into the cytoplasm of NSCLC cells and accelerate NSCLC invasion and migration by upregulating integrinα2β1.A luciferase assay revealed that integrinα2β1 was the direct target of miR-34c-3p,and overexpression of integrinα2β1 could promote the invasion and migration of NSCLC cells.The analysis of exosomes derived from clinical serum samples indicated that the expression of miR-34c-3p was significantly downregulated in exosomes from NSCLC patients compared with that of normal controls.A549-derived exosomes promoted NSCLC cells lung metastases in vivo.Exosomes shuttling low levels of miR-34c-3p were associated with the progression of NSCLC in vitro and in vivo.Our data demonstrate that exosomes shuttling low levels of miR-34c-3p can accelerate the invasion and migration of NSCLC by upregulating integrinα2β1.MiR-34c-3p can be a diagnostic and prognostic marker for NSCLC.High expression of integrinα2β1 is positively related to the migration and metastasis of NSCLC cells.Wenjing Huang Yanyan Yan Yun Liu Minting Lin Jinxiang Ma Wei Zhang Jianwei Dai Jiajun Li Qiaoru Guo Hubiao Chen Bolat Makabel Hong Liu Chaoyue Su Hong Bi Jianye Zhang 2020Signal Transduction and Targeted Therapy2020,5,1:5
13Evolution history and trend of the modern Huanghe River Delta显示文摘The evolvement history of modern Huanghe River Delta tidal flat,coastline and underwater terrain were studied based on the analysis of remote sensing images and water depth data.Based on the analysis of seafloor terrain evolution on different historical stages,a formula simulating the erosion and deposition evolvement model of subaqueous Huanghe River Delta slope was proposed,and the evolvement trend of the subaqueous delta terrain was predicted.The result shows that the equilibrium transition zone is near the water depth of 12 m with seabed erosion in shallower water and accumulation in deeper water during the first 150 a after the river channel was deserted.In the meantime,the underwater slope became gentler and the coastal erosion rate became slow gradually.Then,the subaqueous delta slope changed to up concave from upper convex,and the shape of subaqueous delta disappeared.The coast type changed to silt-mud coast about 100-150 a after the river course was deserted.The erosion depth in the foot of the seawall is calculated based on the formula.MA Yanyan LI Guangxue 2010Acta Oceanologica Sinica2010,29,2:5
14Rb Protein is Essential to the Senescence-Associated Heterochromatic Foci Formation Induced by HMGA2 in Primary WI38 Cells显示文摘细胞的老朽是提供一个障碍给肿瘤的转变的房间周期拘捕的一张不可逆的表格。Rb (Retinoblastoma ) 小径的正直为为衰老的状态的稳定性提供一个分子的基础的联系老朽的 heterochromatin foci (SAHF ) 的形成是必要的。令人惊讶地,尽管高活动性组 A2 蛋白质(HMGA2 ) 能支持 tumorigenesis 并且在肿瘤房间禁止 Rb 功能, HMGA2 的高级表示是足够的在主要房间导致 SAHF 形成。决定 Rb 蛋白质是否在导致 HMGA2 的 SAHF 形成是必要的因此变得重要。在这研究,我们由 HMGA2,典型衰老的标记在被看见的宫外的表示建立了细胞的老朽和 SAHF 汇编 WI38 房间模型,包括 p53, p21 和 p16 的著名 upregulation,并且提高了 SA -- 和 E2F 目标基因的 downregulation 染色的牛乳糖。我们然后证明 Rb 小径禁止者 E7 蛋白质能部分在 WI38 房间在 HMGA2 表示以后废除 SAHF 形成的能力,显示 Rb 是为导致 HMGA2 的 SAHF 形成的一个关键因素。然而, Rb 弄空完全没救 HMGA2 导致的房间生长拘捕,建议 Rb 不是为在 WI38 房间的导致 HMGA2 的老朽的一条独占的小径。Xi Shi Baoqing Tian Lingxia Liu Yanyan Gao Chi Ma Namusamba Mwichie Wenlong Ma Liping Han Baiqu Huang Jun Lu Yu Zhang 2013Journal of Genetics and Genomics2013,40,8:4
15Characterization and Fine Mapping of GLABROUS RICE 2 in Rice显示文摘Glabrous rice exhibits glabrous leaves and hulls because neither of these structures have trichomes on their surfaces.Glabrous rice varieties have become an important germplasm resource in the rice industry because they have considerable packaging efficiency and can reduce skin itching and dust during harvesting,drying,and packing(Shim et al.,2012;Zhang et al.,2012).Trichomes are ubiquitous in land plants and they originate from the expansion of the epidermal cell and then develop through growth,differentiation,or cell division to produce hair-like tissues that extend from epidermalYuping Wang Weilan Chen Peng Qin Yanyan Huang Bingtian Ma Xinhao Ouyang Xuewei Chen Shigui Li 2013Journal of Genetics and Genomics2013,40,11:4
16Three-dimensional printing for heart diseases: clinical application review显示文摘Heart diseases remain the top threat to human health,and the treatment of heart diseases changes with each passing day.Convincing evidence shows that three-dimensional(3D)printing allows for a more precise understanding of the complex anatomy associated with various heart diseases.In addition,3D-printed models of cardiac diseases may serve as effective educational tools and for hands-on simulation of surgical interventions.We introduce examples of the clinical applications of different types of 3D printing based on specific cases and clinical application scenarios of 3D printing in treating heart diseases.We also discuss the limitations and clinically unmet needs of 3D printing in this context.Yanyan Ma Peng Ding Lanlan Li Yang Liu Ping Jin Jiayou Tang Jian Yang 2021Bio-Design and Manufacturing2021,4,3:3
17Extranodal involvement in young patients with diffuse large B-cell lymphoma: distribution, prognostic value and treatment options显示文摘Objective: Extranodal involvement represents a peculiar presentation of diffuse large B-cell lymphoma(DLBCL). Previous studies have suggested that older patients are more prone to extranodal involvement. This study retrospectively addressed the distribution, prognostic value and treatment options of extranodal involvement in young patients with DLBCL.Methods: A total of 329 patients were enrolled according to the inclusion requirements. The effects of gender,extranodal involvement, age-adjusted international prognostic index(aa IPI), rituximab infusion and radiotherapy on patient outcomes were evaluated.Results: Among these patients, 59% presented extranodal involvement in 16 anatomic sites. More than one instance was linked to many poorer clinical characteristics and poorer survival compared with either nodal disease or one instance. In patients with one extranodal lesion, multivariate analysis revealed that the site of extranodal involvement, but not the aa IPI or rituximab infusion, was independently related to the outcome, and radiotherapy had a negative influence on survival.Conclusions: Extranodal involvement is common in younger patients and exhibits a ubiquitous distribution.The site of extranodal involvement is of strong prognostic significance. Radiotherapy for extranodal lesions does not improve patient outcomes.Shuna Yao Junbo Li Zhihua Yao Yuanlin Xu Junfeng Chu Jiuyang Zhang Shuiling Jin Yangyang Huang Jianbo Zhang Jie Ma Yan Zhao Shujun Yang Yanyan Liu 2017Chinese Journal of Cancer Research2017,29,1:3
18Responses of Yellow Sea Cold Water Mass to Typhoon Bolaven显示文摘A two-month seabed-mounted observation(YSG1 area) was carried out in the western Yellow Sea Cold Water Mass(YSCWM) using an RDI-300 K acoustic Doppler current profiler(ADCP) placed at a water depth of 38 m in late summer, 2012. On August 2012, Typhoon Bolaven passed east of YSG1 with a maximum wind speed of 20 m s-1. The water depth, bottom temperature, and profile current velocities(including u, v and w components) were measured, and the results showed that the typhoon could induce horizontal current with speed greater than 70 cm s-1 in the water column, which is especially rare at below 20 meters above bottom(mab). The deepening velocity shear layer had an intense shear velocity of around 10 cm s-1 m-1, which indicated the deepening of the upper mixed layer. In the upper water column(above 20 mab), westward de-tide current with velocity greater than 30 cm s-1 was generated with the typhoon's onshore surge, and the direction of current movement shifted to become southward. In the lower water column, a possible pattern of eastward compensation current and delayed typhoon-driven current was demonstrated. During the typhoon, bottom temperature variation was changed into diurnal pattern because of the combined influence of typhoon and tidal current. The passage of Bolaven greatly intensified local sediment resuspension in the bottom layer. In addition, low-density particles constituted the suspended particulate matter(SPM) around 10 mab, which may be transported from the central South Yellow Sea by the typhoon. Overall, the intensive external force of the Typhoon Bolaven did not completely destroy the local thermocline, and most re-suspended sediments during the typhoon were restricted within the YSCWM.LI Jianchao LI Guangxue XU Jishang QIAO Lulu MA Yanyan DING Dong LIU Shidong 2019Journal of Ocean University of China2019,18,1:3
19Detection of Huanglongbing(citrus greening) based on hyperspectral image analysis and PCR显示文摘Huanglongbing (HLB, citrus greening) is one of the most serious quarantine diseases of citrus worldwide. To monitor in real-time, recognize diseased trees, and efficiently prevent and control HLB disease in citrus, it is necessary to develop a rapid diagnostic method to detect HLB infected plants without symptoms. This study used Newhall navel orange plants as the research subject, and collected normal color leaf samples and chlorotic leaf samples from a healthy orchard and an HLB-infected orchard, respectively. First, hyperspectral data of the upper and lower leaf surfaces were obtained, and then the polymerase chain reaction (PCR) was used to detect the HLB bacterium in each leaf. The PCR test results showed that all samples from the healthy orchard were negative, and a portion of the samples from the infected orchard were positive. According to these results, the leaf samples from the orchards were divided into disease-free leaves and HLB-positive leaves, and the least squares support vector machine recognition model was established based on the leaf hyperspectral reflectance. The effect on the model of the spectra obtained from the upper and lower leaf surfaces was investigated and different pretreatment methods were compared and analyzed. It was observed that the HLB recognition rate values of the calibration and validation sets based on upper leaf surface spectra under 9-point smoothing pretreatment were 100% and 92.5%, respectively. The recognition rate values based on lower leaf surface spectra under the second-order derivative pretreatment were also 100% and 92.5%, respectively. Both upper and lower leaf surface spectra were available for recognition of HLB-infected leaves, and the HLB PCR-positive leaves could be distinguished from the healthy by the hyperspectral modeling analysis. The results of this study show that early and nondestructive detection of HLBinfected leaves without symptoms is possible, which provides a basis for the hyperspectral diagnosis of citrus with HLB.Kejian WANG Dongmei GUO Yao ZHANG Lie DENG Rangjin XIE Qiang LV Shilai YI Yongqiang ZHENG Yanyan MA Shaolan HE 2019Frontiers of Agricultural Science and Engineering2019,6,2:3
20Distribution and its mechanism of suspended particulate matters in the southern Huanghai Sea and the East China Sea in summer显示文摘Water temperature,turbidity,chlorophyll-a and suspended sediment concentration (SSC) were investigated at 61 stations of eight sections in the southern Huanghai Sea (HS) and the East China Sea (ECS) during the summer (28 June to 15 July) of 2006.The horizontal distribution of suspended parti culate matter (SPM) displayed a high concentration inshore and a low value offshore.The maximum value can reach 10.4 mg/dm 3,which can be found at the Changjiang River mouth.For the same site,the SSC was generally higher at the bottom than on the surface.In the vertical direction,distribution characteristics of turbidity can be divided into two types:in the southern HS high values at the bottom while low values on the surface,and in the ECS high values inshore with low values offshore.The thermocline in the HS and the Taiwan Warm Current in the ECS could be important factors preventing the SPM from diffusing upward and seaward.Even the typhoon Ewiniar was not able to work on the major sediment transport under the thermocline during the observation.QIAO Lulu LIU Yong CHEN Jiaojie MA Yanyan LI Guangxue SONG Jun 2011Acta Oceanologica Sinica2011,30,5:3
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