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Development and Evaluation of Intersection-Based Turning Movement Counts Framework Using Two Channel LiDAR Sensors
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作者 Ravi Jagirdar Joyoung Lee +2 位作者 Dejan Besenski Min-Wook Kang Chaitanya Pathak 《Journal of Transportation Technologies》 2023年第4期524-544,共21页
This paper presents vehicle localization and tracking methodology to utilize two-channel LiDAR data for turning movement counts. The proposed methodology uniquely integrates a K-means clustering technique, an inverse ... This paper presents vehicle localization and tracking methodology to utilize two-channel LiDAR data for turning movement counts. The proposed methodology uniquely integrates a K-means clustering technique, an inverse sensor model, and a Kalman filter to obtain the final trajectories of an individual vehicle. The objective of applying K-means clustering is to robustly differentiate LiDAR data generated by pedestrians and multiple vehicles to identify their presence in the LiDAR’s field of view (FOV). To localize the detected vehicle, an inverse sensor model was used to calculate the accurate location of the vehicles in the LiDAR’s FOV with a known LiDAR position. A constant velocity model based Kalman filter is defined to utilize the localized vehicle information to construct its trajectory by combining LiDAR data from the consecutive scanning cycles. To test the accuracy of the proposed methodology, the turning movement data was collected from busy intersections located in Newark, NJ. The results show that the proposed method can effectively develop the trajectories of the turning vehicles at the intersections and has an average accuracy of 83.8%. Obtained R-squared value for localizing the vehicles ranges from 0.87 to 0.89. To measure the accuracy of the proposed method, it is compared with previously developed methods that focused on the application of multiple-channel LiDARs. The comparison shows that the proposed methodology utilizes two-channel LiDAR data effectively which has a low resolution of data cluster and can achieve acceptable accuracy compared to multiple-channel LiDARs and therefore can be used as a cost-effective measure for large-scale data collection of smart cities. 展开更多
关键词 Vehicle Trajectory Construction Two Channel LiDAR Turning Movement Counts RTMS Smart Cities LIDAR
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Isolated intestinal neurofibromatous proliferations in the absence of associated systemic syndromes 被引量:9
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作者 J Elliot Carter Javier A Laurini 《World Journal of Gastroenterology》 SCIE CAS CSCD 2008年第42期6569-6571,共3页
Gastrointestinal tract involvement by neurofi bromatous lesions is rare and occurs most frequently as one of the systemic manifestations of generalized neurofibromatosis type 1 (NF1). In this setting, the lesions may ... Gastrointestinal tract involvement by neurofi bromatous lesions is rare and occurs most frequently as one of the systemic manifestations of generalized neurofibromatosis type 1 (NF1). In this setting, the lesions may manifest as focal scattered neurofi bromas or as an extensive diffuse neural hyperplasia designated ganglioneuromatosis. Occasionally, such lesions may be the initial sign of NF1 in patients without any other clinical manifestations of the disease. Rarely, cases of isolated neurofi bromatosis of the large bowel with no prior or subsequent evidence of generalized neurofi bromatosis have been documented. We present the case of a 52 year-old female with abdominal pain and alternating bowel habits. Colonoscopic evaluation revealed multiple small polyps in the cecum and the presence of nodular mucosa in the colon and rectum. Pathologic evaluation of the biopsies from the cecum, descending colon, sigmoid colon, and rectum revealed tangled fascicles of spindle cells expanding the lamina propia leading to separation of the intestinal crypts. Immunohistochemical stains helped confirm the diagnosis of diffuse intestinal neurofibromatosis. A thorough clinical evaluation failed to reveal any stigmata of generalized neurofibromatosis. This case represents a rare presentation of isolated intestinal neurofi bromatosis in a patient without classic systemic manifestations of generalized neurofibromatosis and highlights the need in such cases for close clinical follow-up to exclude neurofibromatosis type Ⅰ or multiple endocrine neoplasia type Ⅱ. 展开更多
关键词 肠疾病 细胞增殖 神经纤维瘤 治疗方法
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Association of autoimmune hepatitis type 1 in a child with Evans syndrome 被引量:1
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作者 Chaowapong Jarasvaraparn Hamayun Imran +2 位作者 Abdul Siddiqui Felicia Wilson David A Gremse 《World Journal of Hepatology》 CAS 2017年第23期1008-1012,共5页
Autoimmune hepatitis(AIH) is a progressive liver disease that is often associated with extrahepatic autoimmune disorders. Evans syndrome(ES) is a rare autoimmune disorder, which is characterized by immune thrombocytop... Autoimmune hepatitis(AIH) is a progressive liver disease that is often associated with extrahepatic autoimmune disorders. Evans syndrome(ES) is a rare autoimmune disorder, which is characterized by immune thrombocytopenia and autoimmune hemolytic anemia. Association of AIH with ES is rare, especially in children. We report a 3-year-old female with a past medical history of ES who presented with jaundice and significant transaminitis due to AIH type 1. She required multiple treatments with steroids as well as azathioprine, intravenous immunoglobulin and a course of rituximab. 展开更多
关键词 Evans 症候群 自体免疫的肝炎类型 1 孩子
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Concise review on the comparative efficacy of endoscopic ultrasound-guided fine-needle aspiration vs core biopsy in pancreatic masses, upper and lower gastrointestinal submucosal tumors 被引量:1
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作者 Tawfik Khoury Wisam Sbeit +7 位作者 Nicholas Ludvik Divya Nadella Alex Wiles Caitlin Marshall Manoj Kumar Gilad Shapira Alan Schumann Meir Mizrahi 《World Journal of Gastrointestinal Endoscopy》 CAS 2018年第10期267-273,共7页
Endoscopic ultrasound(EUS)-guided fine needle aspiration with or without biopsy(FNA/FNB) are the primary diagnostic tools for gastrointestinal submucosal tumors. EUS-guided fine needle aspiration(EUS-FNA) is considere... Endoscopic ultrasound(EUS)-guided fine needle aspiration with or without biopsy(FNA/FNB) are the primary diagnostic tools for gastrointestinal submucosal tumors. EUS-guided fine needle aspiration(EUS-FNA) is considered a first line diagnostic method for the characterization of pancreatic and upper gastrointestinal lesions, since it allows for the direct visualization of the collection of specimens for cytopathologic analysis. EUSFNA is most effective and accurate when immediate cytologic assessment is permitted by the presence of a cytopathologist on site. Unfortunately, the accuracy and thus the diagnostic yield of collected specimens suffer without this immediate analysis. Recently, a EUS-FNB needle capable of obtaining core samples(fine needle biopsy, FNB) has been developed and has shown promising results. This new tool adds a new dimension to the diagnostic and therapeutic utility of this technique. The aim of the present review is to compare the efficacy of EUS-FNA to that afforded by EUS-FNB in the characterization of pancreatic masses and of upper and lower gastrointestinal submucosal tumors. 展开更多
关键词 Efficacy Safety GASTROINTESTINAL MASSES Fine NEEDLE ASPIRATION and BIOPSY
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Sulindac sulfide selectively increases sensitivity of ABCC1 expressing tumor cells to doxorubicin and glutathione depletion 被引量:2
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作者 Jason D.Whitt Adam B.Keeton +4 位作者 Bernard D.Gary Larry A.Sklar Kamlesh Sodani Zhe-Sheng Chen Gary A.Piazza 《The Journal of Biomedical Research》 CAS CSCD 2016年第2期120-133,共14页
ATP-binding cassette(ABC) transporters ABCC1(MRP1),ABCB1(P-gp),and ABCG2(BCRP) contribute to chemotherapy failure.The primary goals of this study were to characterize the efficacy and mechanism of the nonstero... ATP-binding cassette(ABC) transporters ABCC1(MRP1),ABCB1(P-gp),and ABCG2(BCRP) contribute to chemotherapy failure.The primary goals of this study were to characterize the efficacy and mechanism of the nonsteroidal anti-inflammatory drug(NSAID),sulindac sulfide,to reverse ABCC1 mediated resistance to chemotherapeutic drugs and to determine if sulindac sulfide can influence sensitivity to chemotherapeutic drugs independently of drug efflux.Cytotoxicity assays were performed to measure resistance of ABC-expressing cell lines to doxorubicin and other chemotherapeutic drugs.NSAIDs were tested for the ability to restore sensitivity to resistance selected tumor cell lines,as well as a large panel of standard tumor cell lines.Other experiments characterized the mechanism by which sulindac sulfide inhibits ABCC1 substrate and co-substrate(GSH) transport in isolated membrane vesicles and intact cells.Selective reversal of multi-drug resistance(MDR),decreased efflux of doxorubicin,and fluorescent substrates were demonstrated by sulindac sulfide and a related NSAID,indomethacin,in resistance selected and engineered cell lines expressing ABCC 1,but not ABCB 1 or ABCG2.Sulindac sulfide also inhibited transport of leukotriene C_4 into membrane vesicles.Sulindac sulfide enhanced the sensitivity to doxorubicin in 24 of 47 tumor cell lines,including all melanoma lines tested(7-7).Sulindac sulfide also decreased intracellular GSH in ABCC1 expressing cells,while the glutathione synthesis inhibitor,BSO,selectively increased sensitivity to sulindac sulfide induced cytotoxicity.Sulindac sulfide potently and selectively reverses ABCC1-mediated MDR at clinically achievable concentrations.ABCC1 expressing tumors may be highly sensitive to the direct cytotoxicity of sulindac sulfide,and in combination with chemotherapeutic drugs that induce oxidative stress. 展开更多
关键词 multi-drug resistance doxorubicin sulindac MRP1 glutathione
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Comments on“Non-Relativistic Treatment of a Generalized Inverse Quadratic Yukawa Potential”[Chin. Phys.Lett.34(2017)110301]
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作者 R.C.Woods 《Chinese Physics Letters》 SCIE CAS CSCD 2020年第8期200-200,共1页
Some problems with the article by Oluwadare and Oyewumi[Chin.Phys.Lett.34(2017)110301]are discussed.The previously proposed solution of the Schrödinger wave equation in the generalized inverse quadratic Yukawa po... Some problems with the article by Oluwadare and Oyewumi[Chin.Phys.Lett.34(2017)110301]are discussed.The previously proposed solution of the Schrödinger wave equation in the generalized inverse quadratic Yukawa potential is unsatisfactory for a number of reasons. 展开更多
关键词 YUKAWA s. inverse
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Comparison of a Pain Pump versus Injectable Medication for Analgesia in Knee Arthroscopy
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作者 Albert W. Pearsall Sudhakar G. Madanagopal Kshitij Agrawal 《Open Journal of Orthopedics》 2012年第3期73-79,共7页
As arthroscopic knee procedures have evolved, so has the management of post-operative pain. Traditional pain management included intravenous narcotics, which often resulted in nausea and increased sedation. In an effo... As arthroscopic knee procedures have evolved, so has the management of post-operative pain. Traditional pain management included intravenous narcotics, which often resulted in nausea and increased sedation. In an effort to reduce post-operative pain and minimize complications, the concept of multimodal analgesia evolved, including subcutaneous infiltration of local anesthetic, ketorolac and/or narcotic. We studied the effect upon post-operative pain of combining ropivacaine, ketorolac and morphine injected as a one-time dose compared to the same mixture plus an intraarticular pump administering ropivacaine for 24 hours. Our findings showed that a single subcutaneous and intraarticular injection of ketorolac, morphine and ropivacaine was as effective as this solution plus a 24-hour intraarticular ropivacaine pain pump for post-operative pain relief after outpatient arthroscopic knee surgery. No clinical or radiographic signs of chondrolysis were seen in the knee with the use of intraarticular ropivacaine at an average of 18 months post-operatively. 展开更多
关键词 PAIN PUMP ANESTHETICS Knee ARTHROSCOPY
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Effect of pelvic fixation on ambulation in children with neuromuscular scoliosis
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作者 Luke Drake Hamdi Sukkarieh +5 位作者 Tyler McDonald Eldrin Bhanat Elisa Quince Myles Atkins Patrick Wright Jaysson Brooks 《World Journal of Orthopedics》 2022年第8期753-759,共7页
BACKGROUND The effect of posterior spinal fusion(PSF)incorporating the pelvis on an ambulatory patient’s ability to mobilize after the fusion is not well understood.AIM To see whether a posterior spinal fusion with p... BACKGROUND The effect of posterior spinal fusion(PSF)incorporating the pelvis on an ambulatory patient’s ability to mobilize after the fusion is not well understood.AIM To see whether a posterior spinal fusion with pelvic fixation using iliac or sacral alar iliac screws in ambulatory neuromuscular scoliosis(NMS)patients influences postoperative ambulatory ability.METHODS A retrospective review of all patients with NMS that underwent PSF with fixation incorporating the pelvis between January 1,2012 and February 29,2019.A total of 118 patients were eligible,including 11 ambulatory patients.The primary outcome was the maintenance of ambulatory status postoperatively.Secondary outcomes included postoperative curve magnitude,pelvic obliquity,and complications,comprising infections,instrumentation failure,and any unplanned returns to the operative room.RESULTS The ambulatory function was maintained in all 11 ambulatory NMS patients.One patient had an improvement in functional status with equipment-free ambulation postoperatively.An average postoperative follow-up was 19 mo.The overall complication rate was 19.4%(n=23)with no significant differences between the groups in infection(P=0.365),hardware failure(P=0.505),and reoperation rate(P=1.0).Ambulatory status did not affect complication rate(P=0.967).CONCLUSION Spinal fusion to the pelvis in ambulatory patients with NMS provides effective deformity correction without the reduction in ambulatory capabilities. 展开更多
关键词 Pelvic fixation AMBULATION Neuromuscular scoliosis PEDIATRICS Posterior spinal fusion PELVIS
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Aliteracy Among Teachers?Investigating the Reading Habits of Elementary and Early Childhood Educators
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作者 Rebecca M.Giles Karyn W.Tunks 《Journal of Contemporary Educational Research》 2019年第3期1-7,共7页
Since the reading habits of both preservice and inservice teachers have been linked to their abilities as reading teachers,aliteracy among teachers is particularly distressing.The purpose of this study was to investig... Since the reading habits of both preservice and inservice teachers have been linked to their abilities as reading teachers,aliteracy among teachers is particularly distressing.The purpose of this study was to investigate the amount of leisure time elementary teachers spend reading literature for pleasure.Prekindergarten through sixth grade teachers(N=24)enrolled in a graduate education course logged the minutes they spent engaged in various leisure activities during one week of the summer.Reading literature,defined as the reading of novels,short stories,plays,or poetry in one’s spare time,ranged from 0 to 845 minutes.Of the 13 activities investigated,the highest average amount of time was spent watching movies(M=552.92).Reading literature for pleasure had the eighth highest mean(M=123.13).Pairwise comparisons revealed no significant difference(t=-.795,p<.435)between time spent reading literature and time spent in other non-literature leisure activities.Results or paired samples t-tests indicated that participants spent significantly less time reading newspapers/magazines(t=2.696,p<.013)and reading blogs(t=2.783,p<.011)and significantly more time watching movies(t=-3.287,p<.003)than reading literature for pleasure.It appears that lack of motivation may be a factor in participants’decision to read literature for pleasure as opposed to either lack of time or technological distractions. 展开更多
关键词 aliteracy READING ELEMENTARY TEACHERS LITERACY
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Characterization of CdZnTeSe Nuclear Detector Chemically Etched in Bromine Methanol
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作者 Ezekiel O. Agbalagba Mebougna L. Drabo +5 位作者 Stephen U. Egarievwe Utpal N. Roy Amir H. Davis Mordecai B. Israel Parion L. Alexander Ralph B. James 《Materials Sciences and Applications》 2021年第8期363-373,共11页
Semiconductor nuclear radiation detectors made from tertiary and quaternary compounds of cadmium telluride (CdTe) can operate at room temperature without cryogenic cooling. One of such materials that have become of gr... Semiconductor nuclear radiation detectors made from tertiary and quaternary compounds of cadmium telluride (CdTe) can operate at room temperature without cryogenic cooling. One of such materials that have become of great interest is cadmium zinc telluride selenide (CdZnTeSe). Compared to other CdTe-based materials, such as cadmium zinc telluride (CdZnTe), CdZnTeSe can be grown with much less Te inclusions and sub-grain boundary networks. Chemical etching is often used to smoothen wafer surfaces during detector fabrication. This paper presents the characterization of CdZnTeSe that is chemically etched using bromine methanol solution. Infrared imaging shows that the wafer has no sub-grain boundary networks that often limit detector performance. The current-voltage (I-V) characterization experiment gave a resistivity of 4.6 × 10<sup>10</sup> Ω-cm for the sample. The I-V curve was linear in the ±10 to ±50 volts range. An energy resolution of 7.2% was recorded at 100 V for the 59.6-keV gamma line of <sup>241</sup>Am. 展开更多
关键词 CdZnTeSe Chemical Etching Energy Resolution Gamma-Ray Spectroscopy Infrared Imaging Nuclear Detectors
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基于美国研究生培养模式探讨中医药院校创新型研究生的培养 被引量:1
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作者 胡秀华 唐炳华 +2 位作者 赵俊云 杨向竹 席亚光 《教育教学论坛》 2015年第23期144-145,共2页
研究生教育是我国培养高层次人才的主要方式,也是创新型人才培养的主要途径。文章通过分析美国研究生培养模式,结合我国中医院校研究生培养的特点,从研究生质量问题、研究生课程和教学以及研究生导师情况等方面为切入点来解决培养创新... 研究生教育是我国培养高层次人才的主要方式,也是创新型人才培养的主要途径。文章通过分析美国研究生培养模式,结合我国中医院校研究生培养的特点,从研究生质量问题、研究生课程和教学以及研究生导师情况等方面为切入点来解决培养创新型研究生的问题,改善我国创新型研究生培养模式,提高研究生培养质量。 展开更多
关键词 研究生教育 中医药院校 创新型研究生 培养过程
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The interaction between the Wnt/β-catenin signaling cascade and PKG activation in cancer 被引量:7
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作者 Kevin Lee Gary A Piazza 《The Journal of Biomedical Research》 CAS CSCD 2017年第3期189-196,共8页
The activation of the Wnt/β-catenin signaling cascade has been well studied and documented in colorectal cancer(CRC).The long-term use of non-steroidal anti-inflammatory drugs(NSAIDs) has been shown to reduce the... The activation of the Wnt/β-catenin signaling cascade has been well studied and documented in colorectal cancer(CRC).The long-term use of non-steroidal anti-inflammatory drugs(NSAIDs) has been shown to reduce the incidence and risk of death from CRC in numerous epidemiological studies.The NSA1 D sulindac has also been reported to cause regression of precancerous adenomas in individuals with familial adenomatous polyposis who are at high risk of developing CRC.The mechanism responsible for cancer chemopreventive activity of NSAIDs is not well understood but may be unrelated to their cyclooxygenase inhibitory activity.Emerging evidence suggests that sulindac inhibits the growth of colon tumor cells by suppressing the activity of certain phosphodiesterase isozymes to activate cGMβ-dependent protein kinase,PKG,through the elevation of the second messenger cyclic guanosine monophosphote,cGMP.PKG activation has been shown to inhibit the nuclear translocation of β-catenin,reduce β-catenin mRNA and protein levels,and suppress the transcriptional activity of β-catenin.This review describes the relationship between the Wnt/β-catenin signaling cascade and the activation of PKG through PDE inhibition and elevation of intracellular cGMP levels. 展开更多
关键词 Wnt β-catenin PKG CGMP PDE NSAID colon cancer breast cancer
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Aging:A mitochondrial DNA perspective,critical analysis and an update 被引量:6
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作者 Inna N Shokolenko Glenn L Wilson Mikhail F Alexeyev 《World Journal of Experimental Medicine》 2014年第4期46-57,共12页
The mitochondrial theory of aging, a mainstream theory of aging which once included accumulation of mitochondrial DNA(mt DNA) damage by reactive oxygen species(ROS) as its cornerstone, has been increasingly losing gro... The mitochondrial theory of aging, a mainstream theory of aging which once included accumulation of mitochondrial DNA(mt DNA) damage by reactive oxygen species(ROS) as its cornerstone, has been increasingly losing ground and is undergoing extensive revision due to its inability to explain a growing body of emerging data. Concurrently, the notion of the central role for mtDNA in the aging process is being met with increased skepticism. Our progress in understanding the processes of mtDNA maintenance, repair, damage, and degradation in response to damage has largely refuted the view of mt DNA as being particularly susceptible to ROS-mediated mutagenesis due to its lack of "protective" histones and reduced complement of available DNA repair pathways. Recent research on mitochondrial ROS production has led to the appreciation that mitochondria, even in vitro, produce much less ROS than previously thought, automatically leading to a decreased expectation of physiologically achievable levels of mtDNA damage. New evidence suggests that both experimentally induced oxidative stress and radiation therapy result in very low levels of mtDNA mutagenesis. Recent advances provide evidence against the existence of the "vicious" cycle of mtDNA damage and ROS production. Meta-studies reveal no longevity benefit of increased antioxidant defenses. Simultaneously, exciting new observations from both comparative biology and experimental systems indicate that increased ROS production and oxidative damage to cellular macromolecules, including mtDNA, can be associated with extended longevity. A novel paradigm suggests that increased ROS production in aging may be the result of adaptive signaling rather than a detrimental byproduct of normal respiration that drives aging. Here, we review issues pertaining to the role of mtDNA in aging. 展开更多
关键词 MITOCHONDRIAL DNA REACTIVE OXYGEN SPECIES DNA damage DNA repair Somatic mtDNA mutations Antioxidants REACTIVE OXYGEN SPECIES signaling MITOCHONDRIAL DNA degradation Electron transport AGING
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铬稳定同位素地球化学 被引量:4
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作者 王相力 卫炜 《地学前缘》 EI CAS CSCD 北大核心 2020年第3期78-103,共26页
随着多接收质谱仪分析技术的进步,铬稳定同位素体系在最近二十几年的环境科学和地球化学中得到了越来越广泛的应用。铬元素属于氧化还原敏感元素,在氧化还原反应过程中伴随着较大的同位素分馏。因此,铬同位素在指示现代或古代环境的氧... 随着多接收质谱仪分析技术的进步,铬稳定同位素体系在最近二十几年的环境科学和地球化学中得到了越来越广泛的应用。铬元素属于氧化还原敏感元素,在氧化还原反应过程中伴随着较大的同位素分馏。因此,铬同位素在指示现代或古代环境的氧化还原状态方面有着重要的应用。同时,铬也是中度相容和轻度亲铁元素,使得铬稳定同位素体系也可用来制约高温地质过程(如核幔分异、地幔熔融和岩浆分异结晶等)以及地外行星的演化。本综述首先介绍铬稳定同位素体系,随后讲述分析方法、铬同位素分馏原理以及铬同位素在高温、低温地球化学中的应用。 展开更多
关键词 铬同位素 氧化还原指标 古环境 地外行星演化
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Knowledge acquisition, semantic text mining, and security risks in health and biomedical informatics 被引量:2
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作者 J Harold Pardue William T Gerthoffer 《World Journal of Biological Chemistry》 CAS 2012年第2期27-33,共7页
Computational techniques have been adopted in medi-cal and biological systems for a long time. There is no doubt that the development and application of computational methods will render great help in better understan... Computational techniques have been adopted in medi-cal and biological systems for a long time. There is no doubt that the development and application of computational methods will render great help in better understanding biomedical and biological functions. Large amounts of datasets have been produced by biomedical and biological experiments and simulations. In order for researchers to gain knowledge from origi- nal data, nontrivial transformation is necessary, which is regarded as a critical link in the chain of knowledge acquisition, sharing, and reuse. Challenges that have been encountered include: how to efficiently and effectively represent human knowledge in formal computing models, how to take advantage of semantic text mining techniques rather than traditional syntactic text mining, and how to handle security issues during the knowledge sharing and reuse. This paper summarizes the state-of-the-art in these research directions. We aim to provide readers with an introduction of major computing themes to be applied to the medical and biological research. 展开更多
关键词 BIOMEDICAL informatics BIOINFORMATICS Knowledge SHARING Ontology matching Heterogeneous SEMANTICS SEMANTIC integration SEMANTIC data MINING SEMANTIC text MINING Security risk
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Cenozoic reactivation along the Late Triassic Ganzi-Litang suture,eastern Tibetan Plateau 被引量:1
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作者 W.T.Jackson Jr. D.M.Robinson +1 位作者 A.L.Weislogel X.Jian 《Geoscience Frontiers》 SCIE CAS CSCD 2020年第3期1069-1080,共12页
The spatial-temporal development of Cenozoic reactivation along Mesozoic suture zones in the Tibetan Plateau are first-order parameters needed for assessing models of plateau growth.The Ganzi-Litang suture,in the east... The spatial-temporal development of Cenozoic reactivation along Mesozoic suture zones in the Tibetan Plateau are first-order parameters needed for assessing models of plateau growth.The Ganzi-Litang suture,in the eastern Tibetan Plateau,developed in the Late Triassic because of subduction and closure along the eastern branch of the Paleo-Tethys Ocean.Near the city of Litang,the Ganzi-Litang suture is defined by a melange sequence with faultbound,synorogenic nonmarine strata along the western and eastern flanks,suggesting post-Triassic structural reactivation.We present detrital zircon U-Pb geochronology and field data to determine the timing and style of reactivation along the Ganzi-Litang suture,as well as sedimentary provenance of nonmarine strata.A reverse fault placing melange rock on top of nonmarine strata along the eastern flank of the Ganzi-Litang suture indicates a contractional deformational regime during reactivation.Conglomerate clast counts indicate a local sediment source of recycled Ganzi-Litang suture and Yidun terrane rock.Detrital zircons indicate a localized provenance consisting of recycled material from Triassic Yidun Arc plutons and Triassic Yidun Group turbidite rock.A weighted mean average of Cenozoic zircon grains(n=10) establishes a maximum depositional age of41.5 ± 1.2 Ma for nonmarine strata in the Ganzi-Litang suture.We interpret the maximum depositional age of the nonmarine strata to represent the upper-limit for structural reactivation along the Ganzi-Litang suture while undeformed Neogene strata in the suture zone represent the lower-limit;thereby bracketing structural reactivation from ca.42-25 Ma.Our results provide enhanced spatial-temporal resolution for Cenozoic deformation in the eastern Tibetan Plateau. 展开更多
关键词 NONMARINE STRATA Yidun TERRANE Tibetan plateau Zircon SUTURE zone REACTIVATION
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Caribbean maitotoxin elevates [Ca^(2+)]i and activates non-selective cation channels in HIT-T15 cells
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作者 Xin-Zhong Lu Robert Deckey +2 位作者 Guo-Liang Jiao Hui-Feng Ren Ming Li 《World Journal of Diabetes》 SCIE CAS 2013年第3期70-75,共6页
AIM:To investigate the cytotoxic mechanism of caribbean maitotoxin(MTX-C) in mammalian cells.METHODS:We used whole-cell patch-clamp techniques and fluorescence calcium imaging to determine the cellular toxic mechanism... AIM:To investigate the cytotoxic mechanism of caribbean maitotoxin(MTX-C) in mammalian cells.METHODS:We used whole-cell patch-clamp techniques and fluorescence calcium imaging to determine the cellular toxic mechanisms of MTX-C in insulin secreting HIT-T15 cells,which is a system where the effects of MTX have been observed.HIT-T15 cells stably express L-type calcium current,making it a suitable model for this study.Using the fluorescence calcium indicator Indo-1 AM,we found that there is a profound increase in HIT-T15 intracellular free calcium 3 min after application of 200 nmol/L MTX-C.RESULTS:About 3 min after perfusion of MTX-C,a gradual increase in free calcium concentration was observed.This elevation was sustained throughout the entire recording period.Application of MTX-C did not elicit the L-type calcium current,but large cationiccurrents appeared after applying MTX-C to the extracellular solution.The current-voltage relationship of the cation current is approximately linear within the voltage range from-60 to 50 mV,but flattened at voltages at-80 and-100 mV.These results indicate that MTX-C induces a non-voltage activated,inward current under normal physiological conditions,which by itself or through a secondary mechanism results in a large amount of cationic influx.The biophysical mechanism of MTX-C is different to its isoform,pacific maitotoxin(MTX-P),when the extracellular calcium is removed.CONCLUSION:We conclude that MTX-C causes the opening of non-selective,non-voltage-activated ion channels,which elevates level of intracellular calcium concentration and leads to cellular toxicities. 展开更多
关键词 Maitotoxin Calcium fluorescence High voltage GATED Ca2+ channels WHOLE cell PATCH CLAMP INSULIN secreting CELLS
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临床分子诊断实验室的质量管理(英文)
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作者 Tian-jian CHEN Yue-ying WANG Xi-yu HE 《北京大学学报(医学版)》 CAS CSCD 北大核心 2006年第1期30-32,共3页
After completion of the human genome project, health professionals and the public become more aware aboutthe role of genetic information in medical practice. We are in a transition period to enter a new“genomic medi-... After completion of the human genome project, health professionals and the public become more aware aboutthe role of genetic information in medical practice. We are in a transition period to enter a new“genomic medi-cine”era[1,2]. In the past two decades, many mutations at disease causing genes have been identified and correla-ted to clinical phenotypes. Molecular diagnostic tests for such mutations have been developed and shown their pro-found impacts on clinical medicine and public health. With the development of new genomic technologies, large-scale analysis of human genome and transcriptome are become possible. For example,microarray analysis allows as-sessment of entire expression profile of cancer. By integrating of information from genome and expression profileswith clinical data, cancer molecular classification will become a powerful clinical tool to correlation cancers withtheir prognostics, sensitivity to chemotherapy, and the potential of metastasis[3]. Thus, molecular diagnosis will be-come important soon for clinical physicians and cancer patients on selection of the optimal healthcare approaches. 展开更多
关键词 分子诊断 实验室 医院 质量控制 全面质量管理
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Perinatal arterial ischemic stroke and multiple thrombo-emboli in a term newborn
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作者 Sani Bukari Abdul Hafeez Siddiqui +1 位作者 Madhvi Rajpurkar Meera Chitlur 《Open Journal of Pediatrics》 2012年第1期73-76,共4页
The etiology of perinatal arterial ischemic strokes may be maternal, fetal or both. Venous thrombo-embolism is almost always catheter associated in new-borns. Preliminary guidelines for management of perinatal arteria... The etiology of perinatal arterial ischemic strokes may be maternal, fetal or both. Venous thrombo-embolism is almost always catheter associated in new-borns. Preliminary guidelines for management of perinatal arterial ischemic strokes exist but are mostly based on adult studies. We report a unique case of perinatal arterial ischemic stroke, lower extremity arterial and inferior vena-caval thrombosis. Our patient was treated with unfractionated heparin for 10 days then switched to low molecular heparin to complete 6 months of therapy. The patient responded well to therapy and shows minimal signs of permanent neurologic deficits after 6 months. 展开更多
关键词 PERINATAL arterial ischemic stroke and MULTIPLE throm-bo-emboli in a TERM NEWBORN
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High Dimensional Dataset Compression Using Principal Components
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作者 Michael B. Richman Andrew E. Mercer +2 位作者 Lance M. Leslie Charles A. Doswell III Chad M. Shafer 《Open Journal of Statistics》 2013年第5期356-366,共11页
Until recently, computational power was insufficient to diagonalize atmospheric datasets of order 108 - 109 elements. Eigenanalysis of tens of thousands of variables now can achieve massive data compression for spatia... Until recently, computational power was insufficient to diagonalize atmospheric datasets of order 108 - 109 elements. Eigenanalysis of tens of thousands of variables now can achieve massive data compression for spatial fields with strong correlation properties. Application of eigenanalysis to 26,394 variable dimensions, for three severe weather datasets (tornado, hail and wind) retains 9 - 11 principal components explaining 42% - 52% of the variability. Rotated principal components (RPCs) detect localized coherent data variance structures for each outbreak type and are related to standardized anomalies of the meteorological fields. Our analyses of the RPC loadings and scores show that these graphical displays can efficiently reduce and interpret large datasets. Data is analyzed 24 hours prior to severe weather as a forecasting aid. RPC loadings of sea-level pressure fields show different morphology loadings for each outbreak type. Analysis of low level moisture and temperature RPCs suggests moisture fields for hail and wind which are more related than for tornado outbreaks. Consequently, these patterns can identify precursors of severe weather and discriminate between tornadic and non-tornadic outbreaks. 展开更多
关键词 Data Compression EIGENANALYSIS COMPUTATIONAL COMPLEXITY SEVERE WEATHER Rotated Principal Components
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