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Assessment of stochastic models for GPS measurements with different types of receivers

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chinese Science Bulletin 2008年第20期53卷 3219-3225页

作者： LI BoFeng shen YunZhong XU PeiLiang Department of Surveying and Geo-informatics Engineering Tongji University Shanghai 200092 China Key Laboratory of Advanced Surveying Engineering of SBSM Shanghai 200092 China Disaster Prevention Research Institute Kyoto University Uji Kyoto 611-0011 Japan

The stochastic model plays an important role in parameter estimation. The optimal estimator in the sense of least squares can only be obtained by using the correct stochastic model and consequently guarantees the precise positioning in GPS applications. In this contribution, the GPS measurements, collected by different types of geodetic dual-frequency receiver pairs on ultra-short baselines with a sampling interval of 1 s, are used to address their stochastic models, which include the variances of all observation types, the relationship between the observation accuracy and its elevation angle, the time correlation, as well as the correlation between observation types. The results show that the commonly used stochastic model with the assumption that all the raw GPS measurements are independent with the same variance does not meet the need for precise positioning and the elevation-dependent weight model cannot work well for different receiver and observation types. The time correlation and cross correlation are significant as well. It is therefore concluded that the stochastic model is much associated with the receiver and observation types and should be specified for the receiver and observation types.

关键词：全球定位系统随机模型时间相关互相关

Glutamate and γ-aminobutyric acid receptors and their characteristics in retina

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chinese Science Bulletin 1999年第17期44卷 1548-1556页

作者： Xiongli Yang Ying shen Minghu Han Shanghai Institute of Physiology and Key Laboratory of Neurobiology Chinese Academy of Sciences Shanghai China Graduate student of Department of Biological Science and Technology Zhejiang University Hangzhou China

Glutamate and γ-aminobutyric acid (GABA) are important neurotransmitters in the retinal neuronal circuitry. Using the whole-cell patch clamp technique and a rapid solution changer, glutamate and GABA receptors in the retina have been extensively investigated. Results indicate that glutamate receptors on horizontal cells may be an AMPA preferring subtype,

关键词： retina glutamate γ-aminobutyric acid desensitization receptor patch clamp.

GO molecular function coding based protein subcellular localization prediction

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chinese Science Bulletin 2007年第16期52卷 2240-2245页

作者： shen JinCheng SONG Zhang SUN ZhiRong MOE Key Laboratory of Bioinformatics/Department of Biology Tsinghua University Beijing 100084 China

Subcellular localization is an important feature of proteins which is closely correlated to their function. In this work,we tried to develop a new coding method of using those location predictive molecular function terms of protein as the input for the prediction of subcellular localization. Combined with the amino acid pair composition of the sequence,this coding system is proved to be efficient for support vector machine (SVM) and to have satisfied performance when tested on the RH dataset. Meanwhile,the model also shows robustness against N-terminal uncertainties in sequences.

关键词：蛋白质细胞内定位氨基酸支持向量机

Material differences of auditory source retrieval: Evidence from event-related potential studies

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chinese Science Bulletin 2008年第18期53卷 2801-2812页

作者： NIE AiQing GUO ChunYan shen MoWei Department of Psychology and Behavioral Sciences Zhejiang University Hangzhou 310028 China Department of Psychology Capital Normal University Beijing 100037 China

Two event-related potential experiments were conducted to investigate the temporal and the spatial distributions of the old/new effects for the item recognition task and the auditory source retrieval task using picture and chinese character as stimuli respectively. Stimuli were presented on the center of the screen with their names read out either by female or by male voice simultaneously during the study phase and then two tests were performed separately. One test task was to differentiate the old items from the new ones, and the other task was to judge the items read out by a certain voice during the study phase as targets and other ones as non-targets. The results showed that the old/new effect of the auditory source retrieval task was more sustained over time than that of the item recognition task in both experiments, and the spatial distribution of the former effect was wider than that of the latter one. Both experiments recorded reliable old/new effect over the prefrontal cortex during the source retrieval task. However, there existed some differences of the old/new effect for the auditory source retrieval task between picture and chinese character, and LORETA source analysis indicated that the differ- ences might be rooted in the temporal lobe. These findings demonstrate that the relevancy of the old/new effects between the item recognition task and the auditory source retrieval task supports the dual-process model; the spatial and the temporal distributions of the old/new effect elicited by the auditory source retrieval task are regulated by both the feature of the experimental material and the perceptual attribute of the voice.

关键词：听觉目标识别声源物理研究

Evaluation of energy transfer and utilization efficiency of azo dye removal by different pulsed electrical discharge modes

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chinese Science Bulletin 2008年第12期53卷 1824-1834页

作者： shen YongJun LEI LeCheng ZHANG XingWang Institute of Environmental Pollution Control Technologies Zhejiang University Hangzhou 310028 China

The degradation of an azo dye, acid orange 7 (AO7), caused by different high voltage pulsed electrical discharge modes (spark, streamer and corona discharge) induced by the various initial conductivities was investigated. A new type of pulsed high voltage source with thyratron switch and Blumlein pulse forming net (BPFN) was used. The typical discharge waveforms of voltage, current, power, pulse en-ergy and the pictures of spark, streamer and corona discharge modes were presented. The results in-dicated that pulsed electrical discharges led to complete decolorization and substantial decrease of the chemical oxygen demand (COD) of the dye solution. The main intermediate products were monitored by GC-MS. The discharge modes changed from spark to streamer and to corona discharge, and the streamer length decreased with the liquid conductivity increasing. At a constant input power, the peak voltage, peak current, peak power and energy per pulse of the three discharge modes ranked in the following order: spark > streamer > corona. The effective energy transfer efficiency of AO7 removal was higher for spark discharge (57.2%) than for streamer discharge (40.4%) and corona discharge (27.6%). Moreover, the energy utilization efficiency of AO7 removal for spark discharge was 1.035×10^(-9) mol/J, and for streamer and corona discharge they were 0.646×10^(-9) and 0.589×10^(-9) mol/J. Both the energy transfer efficiency and the energy utilization efficiency of spark discharge were the highest.

关键词：氮能量传递利用效率电流量模式

Negatively and positively charged bacterial aerosol concentration and diversity in natural environments

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chinese Science Bulletin 2013年第26期58卷 3169-3176页

作者： shen FangXia KAI Wei YAO Maosheng State Key Joint Laboratory of Environmental Simulation and Pollution Control College of Environmental Sciences and Engineering Peking University

Bioaerosol charge information is of vital importance for their electrostatic collection. Here, electrostatic means and molecular tools were applied to studying bioaerosol charge dynamics. Positively or negatively charged bioaerosols were collected using an electrostatic sampler operated with a field strength of 1.1 kV cm 1 at a flow rate of 3 L min 1 for 40 min. Those with fewer or no charges bypassing the sampler were also collected using a filter at the downstream of the electrostatic sampler in one environment. The experiments were independently conducted three times in three different environments. The collected bacterial aerosols were cultured directly on agar plates at 26°C, and the colony forming units (CFU) were manually counted. In addition, the CFUs were washed off from the agar plates, and further subjected to polymerase chain reaction (PCR) and denaturing gradient gel electrophoresis (DGGE) for culturable diversity analysis. The results revealed remarkable differences in positively and negatively charged culturable bacterial aerosol concentration and diversity among the studied environments. In the office environment, negatively charged culturable bacterial aerosols appeared to dominate (P = 0.0489), while in outdoor and hotel environments both polarities had similar concentration levels (P = 0.078, P = 0.88, respectively). DGGE patterns for positively charged culturable bacterial aerosols were shown strikingly different from those of negatively charged regardless of the sampling environments. In addition, for each of the environments positively charged culturable bacterial aerosols collected were found to have more band pattern similarity with those positively charged for respective regions of agar plates than those negatively charged, and vice versa. The information developed here is useful for developing efficient electrostatic sampling protocols for bioaerosols.

关键词：气溶胶浓度多样性分析办公环境正电荷细菌生物气溶胶变性梯度凝胶电泳静电收集

Sr-Nd-Pb isotopes of Tertiary volcanics of King George Island, Antarctica

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chinese Science Bulletin 1997年第22期42卷 1913-1918页

作者： Xing, GF shen, WZ Wang, DZ Jin, QM Nanjing Inst Geol & Mineral Resources Nanjing 210016 Peoples R China

1 Geological settingThe King George Island is the largest one in South Shetland Islands, West Antarctica,with an area of 1200 km^2. Most of it is covered by ice and snow all the year round. It consistsmainly of Tertia... 详细信息

关键词： Sr-Nd-Pb isotopes Tertiary volcanics King George Island Antarctica.

Effects of dietary tert-butylhydroquinone on domoic acid metabolism and transcription of detoxification-related liver genes in red sea bream Pagrus major

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chinese Science Bulletin 2013年第16期58卷 1906-1911页

作者： HE Shan LIANG XuFang shen Dan ZHANG WenBing MAI KangSen Key Laboratory of Freshwater Animal Breeding of Ministry of Agriculture College of Fisheries Huazhong Agricultural University Key Laboratory of Mariculture of Ministry of Education Ocean University of China

Domoic acid (DA) is a neuroexcitatory amino acid that is produced by Pseudo-nitzschia during harmful algal blooms (HAB). Accumulation of DA can be transferred through food chain and cause neuronal damage in marine animal and in human. Like other algal toxins, DA was suggested to increase the oxidative stress and increase the detoxification-related gene expression in fish. The widely used food antioxidant, tert-butylhydroquinone (tBHQ), was known to induce a wide range of antioxidative potentials such as elevation of the glutathione levels and glutathione S-transferases (GSTs), via the activation of antioxidant response elements (AREs). In this study, the influences of dietary tBHQ on domoic acid (DA) metabolism and detoxification-related gene transcription were investigated both in vivo and in vitro. Oral administration of tBHQ resulted in significant decreases of DA accumulation of liver tissues in which red sea bream were fed with a single dose of 10 mg DA and 100 mg tBHQ per kg body weight per fish. Real-time PCR further revealed that the mRNA levels of AHR/ARNT/CYP1A1/GSTA1/GSTR were up-regulated in the above liver tissues at 72 h post tBHQ treatment. In consistence, tBHQ exposure also resulted in increased mRNA transcription of GSTA1, GSTA2 and GSTR in cultured red sea bream hepatocytes. Collectively, our findings in this research suggested that the dietary intake of tBHQ accelerated DA metabolism in fish, through mechanisms involving altered transcription of detoxification- related liver genes.

关键词： mRNA转录相关基因软骨藻酸特丁基对苯二酚酸代谢真鲷解毒肝脏

Decoding hereditary spastic paraplegia pathogenicity through transcriptomic profiling

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Zoological Research 2023年第3期44卷 650-662页

作者： Nicolas James Ho Xiao Chen Yong Lei shen Gu School of Biomedical Sciences Faculty of MedicineThe Chinese University of Hong KongHong Kong SARChina Dr.Li Dak Sum-Yip Yio chin Center for Stem Cells and Regenerative Medicine and Department of Orthopedic Surgery of the Second Affiliated Hospital Zhejiang University School of MedicineHangzhouZhejiang 310058China Key Laboratory of Tissue Engineering and Regenerative Medicine of Zhejiang Province Zhejiang University School of MedicineHangzhouZhejiang 310058China Zhejiang University-University of Edinburgh Institute&School of Basic Medicine Zhejiang University School of MedicineHangzhouZhejiang 310058China Department of Sports Medicine Zhejiang University School of MedicineHangzhouZhejiang 310058China china Orthopedic Regenerative Medicine Group(CORMed) HangzhouZhejiang310058 China School of Medicine The Chinese University of Hong Kong(Shenzhen)ShenzhenGuangdong 518172China The chinese University of Hong Kong(shenzhen) Shenzhen Futian Biomedical Innovation R&D CenterShenzhenGuangdong 518172China Key Laboratory for Regenerative Medicine Ministry of EducationSchool of Biomedical SciencesFaculty of MedicineThe Chinese University of Hong KongHong Kong SARChina Kunming Institute of Zoology-The chinese University of Hong Kong(KIZ-CUHK)Joint Laboratory of Bioresources and Molecular Research of Common Diseases Hong Kong SARChina Hong Kong Branch of CAS Center for Excellence in Animal Evolution and Genetics The Chinese University of Hong KongHong Kong SARChina

Hereditary spastic paraplegia(HSP)is a group of genetic motor neuron diseases resulting from length-dependent axonal degeneration of the corticospinal upper motor *** to the advancement of next-generation sequencing,more than 70 novel HSP disease-causing genes have been identified in the past *** this,our understanding of HSP physiopathology and the development of efficient management and treatment strategies remain *** major challenge in studying HSP pathogenicity is selective neuronal vulnerability,characterized by the manifestation of clinical symptoms that are restricted to specific neuronal populations,despite the presence of germline disease-causing variants in every cell of the ***,disease genes may exhibit ubiquitous expression patterns and involve a myriad of different pathways to cause motor neuron *** the current review,we explore the correlation between transcriptomic data and clinical manifestations,as well as the importance of interspecies models by comparing tissue-specific transcriptomic profiles of humans and mice,expression patterns of different genes in the brain during development,and single-cell transcriptomic data from related ***,we discuss the potential of emerging single-cell RNA sequencing technologies to resolve unanswered questions related to HSP pathogenicity.

关键词： degeneration transcript hereditary