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World Journal of gastroenterology 2014年第26期20卷 8458-8470页

作者： Daniel Delitto Eva Vertes-george Steven J Hughes Kevin E Behrns Jose g Trevino Department of Surgery University of Florida-Gainesville Department of Pathology University of Florida-Gainesville

Pancreatic ductal adenocarcinoma is the 4th leading cause of cancer deaths in the United States. The majority of patients are candidates only for palliative chemotherapy, which has proven largely ineffective in halting tumor progression. One proposed mechanism of chemoresistance involves signaling via the mesenchymal-epithelial transition factor protein (MET), a previously established pathway critical to cell proliferation and migration. Here, we review the literature to characterize the role of MET in the development of tumorigenesis, metastasis and chemoresistance, highlighting the potential of MET as a therapeutic target in pancreatic cancer. In this review, we characterize the role of c-Met in the development of tumorigenesis, metastasis and chemoresistance, highlighting the potential of c-Met as a therapeutic target in pancreatic cancer.

关键词： Pancreatic adenocarcinoma c-Met Chemoresistance Receptor tyrosine kinase

Localization and role of metabotropic glutamate receptors subtype 5 in the gastrointestinal tract

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World Journal of gastroenterology 2017年第25期23卷 4500-4507页

作者： Andrea Ferrigno Clarissa Berardo Laura g Di Pasqua Veronica Siciliano Plinio Richelmi Mariapia Vairetti Department of Internal Medicine and Therapeutics (Cellular and Molecular Pharmacology and Toxicology) University of Pavia

Metabotropic glutamate receptor subtype 5 (mgluR5) is a group I mglu subfamily of receptors coupled to the inositol trisphosphate/diacylglycerol pathway. Like other mgluR subtypes, mgluR5s contain a phylogenetically conserved, extracellular orthosteric binding site and a more variable allosteric binding site, located on the heptahelical transmembrane domain. The mgluR5 receptor has proved to be a key pharmacological target in conditions affecting the central nervous system (CNS) but its presence outside the CNS underscores its potential role in pathologies affecting peripheral organs such as the gastrointestinal (gI) tract and accessory digestive organs such as the tongue, liver and pancreas. Following identification of mgluR5s in the mouth, various studies have subsequently demonstrated its involvement in mechanical allodynia, inflammation, pain and oral cancer. mgluR5 expression has also been identified in gastroesophageal vagal pathways. Indeed, experimental and human studies have demonstrated that mgluR5 blockade reduces transient lower sphincter relaxation and reflux episodes. In the intestine, mgluR5s have been shown to be involved in the control of intestinal inﬂammation, visceral pain and the epithelial barrier function. In the liver, mgluR5s have a permissive role in the onset of ischemic injury in rat and mice hepatocytes. Conversely, livers from mice treated with selective negative allosteric modulators and mgluR5 knockout mice are protected against ischemic injury. Similar results have been observed in experimental models of free-radical injury and in vivo mouse models of acetaminophen intoxication. Finally, mgluR5s in the pancreas are associated with insulin secretion control. The picture is, however, far from complete as the review attempts to establish in particular as regards identifying specific targets and innovative therapeutic approaches for the treatment of gI disorders.

关键词： Metabotropic glutamate receptor subtype 5 Esophagus Intestine Liver Pancreas

Improving the reaction mix of a Pichia pastoris cell-free system using a design of experiments approach to minimise experimental effort

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Synthetic and Systems Biotechnology 2020年第3期5卷 137-144页

作者： Alex J.Spice Rochelle Aw Daniel g.Bracewell Karen M.Polizzi Department of Chemical Engineering Imperial College LondonLondonUK Imperial College Centre for Synthetic Biology Imperial College LondonUK Department of Biochemical Engineering University College LondonLondonUK

A renaissance in cell-free protein synthesis(CFPS)is underway,enabled by the acceleration and adoption of synthetic biology *** has emerged as a powerful platform technology for synthetic gene network design,biosensing and on-demand *** primarily of bacterial origin,cell-free extracts derived from a variety of host organisms have been explored,aiming to capitalise on cellular diversity and the advantageous properties associated with those ***,cell-free extracts produced from eukaryotes are often overlooked due to their relatively low yields,despite the potential for improved protein folding and posttranslational *** we describe further development of a Pichia pastoris cell-free platform,a widely used expression host in both academia and the biopharmaceutical *** a minimised Design of Experiments(DOE)approach,we were able to increase the productivity of the system by improving the composition of the complex reaction *** was achieved in a minimal number of experimental runs,within the constraints of the design and without the need for liquid-handling *** doing so,we were able to estimate the main effects impacting productivity in the system and increased the protein synthesis of firefly luciferase and the biopharmaceutical HSA by 4.8-fold and 3.5-fold,*** study highlights the ***-based cell-free system as a highly productive eukaryotic platform and displays the value of minimised DOE designs.

关键词： Cell-free protein synthesis Pichia pastoris Synthetic biology Design of experiments(DOE)

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基于电路裁剪的统计时钟偏差估计方法

微电子学 2007年第5期37卷 632-635页

作者：方君陆伟成赵文庆复旦大学专用集成电路与系统国家重点实验室上海201203

随着集成电路特征尺寸的不断缩小,工艺偏差引起时钟偏差的不确定性,导致时钟偏差呈现出一定的统计特性。分析了哪些时钟路径可能会成为最长、最短路径,提出了一种基于电路裁剪的统计时钟偏差估计方法,可以快速估计时钟偏差的统计特性。... 详细信息

随着集成电路特征尺寸的不断缩小,工艺偏差引起时钟偏差的不确定性,导致时钟偏差呈现出一定的统计特性。分析了哪些时钟路径可能会成为最长、最短路径,提出了一种基于电路裁剪的统计时钟偏差估计方法,可以快速估计时钟偏差的统计特性。实验结果表明,提出的算法可以在很小的精度损失下提高电路模拟的速度。

关键词：工艺偏差时钟偏差电路裁剪

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局部地质条件对强地面运动影响的剪切波模拟

地球物理学报 2000年第1期43卷 81-90页

作者：孙若昧 F.Vaccari F.Vaccari g.F.Panza g.F.Panza 中国科学院地质与地球物理研究所北京100101 DipartimentodiScienzedella.Terra.Universita’degliStudidiTrieste italy31000 CNR-gNDT Gruppo Nazionale per la Terremoti InternationalCenter forTheoreticalPhysics

采用多阶振型和有限差分联立的混合法，依据北京西集一郎府地区的地质条件，模拟了１９７６年唐山地震所引起的该区的剪切波运动；计算了工程上常用的峰值加速度和总能量．在夏垫断裂两侧的最大振幅和总能量的差异分别为２００％和７０... 详细信息

采用多阶振型和有限差分联立的混合法，依据北京西集一郎府地区的地质条件，模拟了１９７６年唐山地震所引起的该区的剪切波运动；计算了工程上常用的峰值加速度和总能量．在夏垫断裂两侧的最大振幅和总能量的差异分别为２００％和７００％，研究结果可以解释唐山地震时西集一郎府一带所观测到的异常烈度．

关键词：合成地震图局部地质唐山地震地面运动剪切波

A study on deep learning algorithm performance on weed and crop species identification under different image background

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Artificial Intelligence in Agriculture 2022年第1期6卷 242-256页

作者： Sunil g C Cengiz Koparan Mohammed Raju Ahmed Yu Zhang Kirk Howatt Xin Sun Department of Agricultural and Biosystems Engineering North Dakota State UniversityFargoND 58108USA Department of Plant Sciences North Dakota State UniversityPO Box 6050FargoND 58108-6050USA

Weed identification is fundamental toward developing a deep learning-based weed control *** learning algorithms assist to build a weed detection model by using weed and crop *** dynamic environmental conditions such as ambient lighting,moving cameras,or varying image backgrounds could affect the performance of deep learning *** are limited studies on how the different image backgrounds would impact the deep learning algorithms for weed *** objective of this research was to test deep learning weed identification model performance in images with potting mix(non-uniform)and black pebbled(uniform)backgrounds *** weed and crop images were acquired by four canon digital cameras in the greenhouse with both uniform and non-uniform background conditions.A Convolutional Neural Network(CNN),Visual group geometry(Vgg16),and Residual Network(ResNet50)deep learning architectures were used to build weed classification *** model built from uniform background images was tested on images with a non-uniform background,as well as model built from non-uniform background images was tested on images with uniform *** showed that the Vgg16 and ResNet50 models built from non-uniform background images were evaluated on the uniform background,achieving models'performance with an average f1-score of 82.75%and 75%,***,the Vgg16 and ResNet50 models built from uniform background images were evaluated on the non-uniform background images,achieving models'performance with an average f1-score of 77.5%and 68.4%*** the Vgg16 and ResNet50 models'performances were im-proved with average f1-score values between 92%and 99%when both uniform and non-uniform background images were used to build the *** appears that the model performances are reduced when they are tested with images that have different object background than the ones used for building the model.

关键词： Computer vision Deep learning Image background Neural network Weed classification

Maximizing dirty-paper coding rate of RIS-assisted multi-user MIMO broadcast channels

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Intelligent and Converged Networks 2022年第1期3卷 64-73页

作者： Mohamed A.Elmossallamy Radwa Sultan Karim g.Seddik geoffery Ye Li Zhu Han Qualcomm Inc. BoxboroughMA 01719USA Electrical and Computer Engineering Department and the Computer Science Department University of HoustonHoustonTX 77004USA. the Electrical and Computer Engineering Department Manhattan CollegeRiverdaleNY 10471USA. Electronics and Communications Engineering Department American University in CairoNew Cairo 11835Egypt. Department of Electrical and Electronic Engineering Imperial College LondonLondonSW72AZUK

We consider a downlink multi-user scenario and investigate the use of reconfigurable intelligent surfaces(RISs)to maximize the dirty-paper-coding(DPC)sum rate of the RIS-assisted broadcast *** from prior works,which maximize the rate achievable by linear precoders,we assume a capacity-achieving DPC scheme is employed at the transmitter and optimize the transmit covariances and RIS reflection coefficients to directly maximize the sum capacity of the broadcast *** propose an optimization algorithm that iteratively alternates between optimizing the transmit covariances using convex optimization and the RIS reflection coefficients using Riemannian manifold *** results show that the proposed technique can be used to effectively improve the sum capacity in a variety of scenarios compared to benchmark schemes.

关键词： broadcast channels dirty-paper coding multiple-input-multiple-output(MIMO) reconfigurable intelligent surfaces

Heterogeneous and homogeneous reactive flow of magnetite-water nanofluid over a magnetized moving plate

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Propulsion and Power Research 2022年第2期11卷 265-275页

作者： C.S.Sravanthi F.Mabood S.g.Nabi S.A.Shehzad Department of Mathematics Faculty of ScienceThe Maharaja Sayajirao University of BarodaVadodara390002GujaratIndia Department of Information Technology Fanshawe College LondonONN5Y 5R6Canada Department of Mathematics COMSATS University IslamabadSahiwal57000Pakistan

This model is dedicated to visualizing the nature of magnetite-water nanoliquid induced by a permeable plate having variable magnetic effect,non-linear radiation,heterogeneous and homogeneous chemically reactive *** system of momentum,thermal and concentration expressions is formulated and transformed from the partial to ordinary differential systems by using the adequate *** highly non-linear system is solved through RKF(Runge-Kutta-Fehlberg)numerical *** parameters such as suction/injection,magnetic,and radiation effects as well as other relevant parameters are *** graphs show that the rise in radiation parameter numerically improves the thermal distribution,implying a faster heat transfer ***-linear radiation has greater effect on temperature than the linear *** the volume concentration effect reveals that the friction factor increase with the enhancement of nanoparticle *** is also observed that,plate velocity decreases the skin-friction but increases the wall heat transfer for both suction and blowing *** results indicate that the current research has a strong agreement with the relevant data in a limiting approach.

关键词： Homogeneous-heterogeneous reactions Non-linear radiation Variable magnetic field Nanofluid Moving plate

Total estimated effective doses from radiologic imaging modalities of children with cancer:a single center experience

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World Journal of Pediatrics 2017年第3期13卷 242-247页

作者： Derya Ozyorük Suna Emir HacιAhmet Demir gülsah Bayram Kabacam Bahattin Tunc Division of Pediatric Oncology Ankara Children's Hematology and Oncology Education and Research HospitalAnkaraTurkey Division of Radiology Ankara Children's Hematology and Oncology Education and Research HospitalAnkaraTurkey

Background:Recently,awareness of the cumulative radiation exposure for pediatric oncology patients has been increasing,together with increased survival rates and longer life *** aim of our study was to quantify the amount of ionising radiation from imaging modalities of pediatric oncology ***:Eighty-eight patients who were diagnosed with childhood cancer and followed up for 5 years between 2004-2014 in our center were included in the ***' medical files were reviewed retrospectively for imaging history in the first 5 years after *** estimated effective doses from radiologic imaging modalities were ***,the basic demographic data,histologic type,stage,and outcomes of disease were collected for all ***:The individual total estimated effective doses ranged from 8.73 to 167 mSv,with a median of 62.92 *** tomography was the greatest contributor of total effective *** doses ranged 21.45-113.20 mSv (median:62.92 mSv) in Hodgkin lymphoma,12.53-167.10 mSv (median:52 mSv) in non-Hodgkin lymphoma,4.13-172.98 mSv (median:52 mSv) in neuroblastoma,31-149.89 mSv (median:63.10 mSv) in Wilms' tumor,11.50-73.72 mSv (median:36.90 mSv) in germ cell tumor,26.46-125.86 mSv (median:80.90 mSv) in other solid tumor and 0.02-13.31 mSv (5.25 mSv) in brain tumor ***-two children (25%) died with progressive disease during the 5-year follow-up ***:Similar to previous studies,the total estimated effective doses in children with cancer have been found various according to diagnosis,stage and clinical *** clarify the harmfull effects of radiation burden,prospective studies should be conducted in children with cancer.

关键词： children effective dose ionizing radiation

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偶氮苯磺酸衍生物的光致顺反异构化机理

物理化学学报 2009年第11期25卷 2296-2304页

作者：朱玥蒲敏何静 EVANS David g 北京化工大学化工资源有效利用国家重点实验室北京100029

基于密度泛函理论(DFT)中的B3LYP方法,在6-311++g(d,p)水平上全优化得到了3,3′-偶氮苯磺酸(3,3′-AbS)在S0和T1态顺反异构化机理.在S0态存在两种异构化途径:绕角NNC反转和绕NC键旋转相结合的形式和单纯的绕CNNC二面角旋转形式,两种异... 详细信息

基于密度泛函理论(DFT)中的B3LYP方法,在6-311++g(d,p)水平上全优化得到了3,3′-偶氮苯磺酸(3,3′-AbS)在S0和T1态顺反异构化机理.在S0态存在两种异构化途径:绕角NNC反转和绕NC键旋转相结合的形式和单纯的绕CNNC二面角旋转形式,两种异构化途径的能垒分别为94.2和124.3kJ·mol-1.有必要指出的是,在反转与旋转结合的途径上存在二次过渡态.在T1态上仅存在旋转途径且其能垒为21.1kJ·mol-1.采用含时密度泛函理论(TD-DFT),在B3LYP/6-311++g(d,p)水平上,沿着基态的两种异构化途径计算得到了T1,S1,T2和S2态的垂直激发的势能剖面,分析了可能的光致异构化途径.当激发光波长为330nm时,反应物分子被激发到S2态,然后弛豫到较低的能态S1发生异构化反应,旋转途径存在两条活化途径:(1)沿着S1/S0的圆锥交叉点衰变到产物;(2)由S1态弛豫到T1态后,在S0-T1-S0的区域发生异构化,再转化到产物.计算结果表明,3,3′-AbS通过反转和旋转的结合形式实现在S0态的异构化,而被激发后倾向于沿着旋转坐标作为其主要的异构化途径.

关键词：密度泛函理论 3 3′-偶氮苯磺酸光异构化机理激发态势能面