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光纤和铜缆在宽带接入网部署中的竞争

通讯世界 2008年第4期14卷 51-52页

作者： venkat Sundaresan Ikanos Communication公司产品市场部

当今的运营商都有一个终极目标：建立能够提供多种新兴及能增加收益的语音、视频和数据服务的宽带网络。提供涵盖多种应用的服务，运营商就能在固话业务收入减少、移动电话业务接近饱和点的低谷期吸引和留住客户。对运营商来说，能否成... 详细信息

当今的运营商都有一个终极目标：建立能够提供多种新兴及能增加收益的语音、视频和数据服务的宽带网络。提供涵盖多种应用的服务，运营商就能在固话业务收入减少、移动电话业务接近饱和点的低谷期吸引和留住客户。对运营商来说，能否成功最终取决于其所选择的接入网体系。运营商构建其网络的方法差异可能很大；可能采用全光纤布设而造成建设过度，也可能最大限度地挖掘其现有铜缆电话网络设施的潜力。

关键词：宽带接入网全光纤铜缆移动电话业务竞争部署宽带网络数据服务

AR/VR虚拟显示光学测量及IEC国际标准进展

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科技导报 2018年第9期36卷 32-35页

作者：牟希 venkat venkataramanan 乔波牟同升杭州三泰检测技术有限公司杭州311305 浙江三色光电技术有限公司湖州313216 浙江大学光电科学与工程学院杭州310007

虚拟现实、增强现实技术近年获得快速发展,但虚拟显示的视觉舒适度、体验感和实用性仍有待提高。如何对虚拟显示的光学性能、图像质量等关键性能指标进行量化评价和准确测量,是产业界非常关注的问题。AR/VR虚拟图像与液晶显示屏等传统... 详细信息

虚拟现实、增强现实技术近年获得快速发展,但虚拟显示的视觉舒适度、体验感和实用性仍有待提高。如何对虚拟显示的光学性能、图像质量等关键性能指标进行量化评价和准确测量,是产业界非常关注的问题。AR/VR虚拟图像与液晶显示屏等传统显示图像的成像方式不同,测量方法有较大差别,本文根据虚拟显示的成像方式,提出了模拟人眼的入瞳、视野、视角方向及光谱响应等特性的测量技术。同时,结合IEC TC110 WG12＂穿戴显示＂工作组的标准化工作情况,介绍了AR/VR虚拟显示光学测量方法国际标准化的进展。

关键词： AR/VR 穿戴显示虚拟图像光学测量标准化

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便携式应用的半导体产品封装发展回顾

电子工业专用设备 2006年第4期35卷 3-4,22页

作者： venkat Iyer 飞兆半导体公司

半导体封装主要是提供一个媒介,把精细的硅芯片连接到较粗糙间距的印制电路板上,并保护器件免于受潮.这些年间,虽然这个功能并未改变,但封装技术已远较从前复杂.由于芯片的性能逐步复杂封装已肩负着全部散热的责任,这些热量不能成为限... 详细信息

半导体封装主要是提供一个媒介,把精细的硅芯片连接到较粗糙间距的印制电路板上,并保护器件免于受潮.这些年间,虽然这个功能并未改变,但封装技术已远较从前复杂.由于芯片的性能逐步复杂封装已肩负着全部散热的责任,这些热量不能成为限制部件电子性能的因素.而且对便携式应用而言,由于空间越来越宝贵,也需要更小和更薄的封装.随着硅片工作频率的提高,走线电感需要减小.与此同时,封装方案必须具备成本效益以满足当前消费电子应用的价格目标.鉴于硅技术不断发展,封装不得不变得更轻薄、散热性能更佳、速度更快及成本更低!

关键词：半导体封装便携式应用半导体产品成本效益散热性能印制电路板保护器件封装技术电子性能工作频率

Prognostic value of pre-treatment F-18-FDG PET-CT in patients with hepatocellular carcinoma undergoing radioembolization

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World Journal of Gastroenterology 2016年第47期22卷 10406-10414页

作者： Yazan Abuodeh Arash O Naghavi Kamran A Ahmed Puja S venkat Youngchul Kim Bela Kis Junsung Choi Benjamin Biebel Jennifer Sweeney Daniel A Anaya Richard Kim Mokenge Malafa Jessica M Frakes Sarah E Hoffe Ghassan El-Haddad Department of Radiation Oncology H Lee Moffitt Cancer Center and Research Institute Department of Interventional Radiology H Lee Moffitt Cancer Center and Research Institute Department of Gastrointestinal Oncology H Lee Moffitt Cancer Center and Research Institute

AIM To evaluate the value of pre-treatment 18F-FDG PET/CT in patients with HCC following liver *** We identified 34 patients with HCC who underwent an FDG PET/CT scan prior to hepatic radioembolization at our institution between 2009 and 2013. Patients wereseen in clinic one month after radioembolization and then at 2-3 mo intervals. We assessed the influence of FDG tumor uptake on outcomes including local liver control(LLC), distant liver control(DLC), time to distant metastases(DM), progression free survival(PFS) and overall survival(OS).RESULTS The majority of patients were males(n = 25, 74%), and had Child Pugh Class A(n = 31, 91%), with a median age of 68 years(46-84 years). FDG-avid disease was found in 19(56%) patients with SUVmax ranging from 3 to 20. Female patients were more likely to have an FDG-avid HCC(P = 0.02). Median follow up of patients following radioembolization was 12 months(1.2-62.8 mo). FDG-avid disease was associated with a decreased 1 year LLC, DLC, DM and PFS(P < 0.05). Using multivariate analysis, FDG avidity predicted for LLC, DLC, and PFS(all P < 0.05).CONCLUSION In this retrospective study, pre-treatment HCC FDGavidity was found to be associated with worse LLC, DLC, and PFS following radioembolization. Larger studies are needed to validate our initial findings to assess the role of F-18-FDG PET/CT scans as biomarker for patients with HCC following radioembolization.

关键词： F-18 fluorodeoxyglucose 宠物 Hepatocellular 癌 Radioembolization 预后 Biomarker

A clinically isolated syndrome:butterfly glioma mimic

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Neuroimmunology and Neuroinflammation 2015年第1期2卷 174-178页

作者： Ramshekhar Menon Bejoy Thomas Hariharan venkat Easwer Samvedam Sandhyamani Amita Nair Muralidharan Nair Department of Neurology Sree Chitra Tirunal Institute for Medical Sciences and TechnologyTrivandrum 695011KeralaIndia Department of Imaging Sciences and Interventional Radiology Sree Chitra Tirunal Institute for Medical Sciences and TechnologyTrivandrum 695011KeralaIndia Department of Neurosurgery Sree Chitra Tirunal Institute for Medical Sciences and TechnologyTrivandrum 695011KeralaIndia Department of Pathology Sree Chitra Tirunal Institute for Medical Sciences and TechnologyTrivandrum 695011KeralaIndia

The report explores a unique and treatable“butterfly”-glioma mimic and the neuroimaging characteristics that help to diagnose this entity.A 35-year-old patient presented with subacute-onset,progressive frontal lobe dysfunction followed by features of raised intracranial *** features were consistent with a“butterfly”lesion that favored the possibility of a gliomatosis cerebri with significant edema and marked corpus callosum and fornix ***-enhanced and perfusion images revealed a confluent tumefactive lesion with a characteristic“broken-ring”pattern of enhancement,mass-effect and low perfusion;features favoring an alternative inflammatory *** was peculiar as calloso-forniceal involvement of this nature has not been previously reported in inflammatory demyelinating mass *** was confirmed as a tumefactive demyelination on *** treatment,on clinical and imaging follow-up,significant resolution was evident suggesting a monophasic *** case highlights the stringent clinico-radiological-pathological approach required in the evaluation and management of butterfly lesions despite the striking imaging *** demyelination in this patient represents a clinically isolated syndromic presentation of an inflammatory pathology that can resemble gliomatosis ***“butterfly”-glioma mimics are scarcely reported in the literature,are eminently treatable with variable prognosis and prone for relapse.

关键词： Butterfly lesions glioma tumefactive demyelination

Differentiation of Pancreatic Ductal Epithelial Cells into Insulin Like Cell Clusters in Chronic Pancreatitis

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Open Journal of Endocrine and Metabolic Diseases 2015年第12期5卷 177-183页

作者： Pondugala Pavan Kumar Gaddipati Radhika G. venkat Rao D. Nageshwar Reddy M. Sasikala Asian Health Care Foundation Somajiguda Hyderabad India Asian Institute of Gastroenterology Somajiguda Hyderabad India

Background/Aim: Islet regeneration in chronic pancreatitis (CP) is relevant for managing the associated loss of endocrine function. Because ductal epithelial cells were earlier demonstrated to differentiate into pancreatic endocrine mass, we evaluated their proliferation and differentiation in chronic pancreatitis. Methods: Pancreatic ducts were obtained from surgically resected pancreata of 12 patients with chronic pancreatitis and 15 control subjects. CK19 positive ductal cells were evaluated for their proliferating and differentiating abilities upon immunostaining with Ki 67 and hormone positivity for insulin and glucagon, apart from monitoring Pdx 1 expression. Results: In comparison to the controls, a greater number of proliferating pancreatic ductal epithelial cells (PDECs) were observed under conditions of CP. The increase in Pdx1 expressing PDECs (22%) and proliferating Pdx1 expressing PDECs (30%) was significant (P < 0.04). Number of cells expressing insulin/glucagon in the exocrine ducts increased significantly in CP as compared to controls (P ?β?cell mass adjacent to the ducts increased by 28%.?Conclusion: Enhanced capability of PDECs to proliferate and differentiate into endocrine mass suggests that PDECs form a source of progenitors for cell based therapy in chronic pancreatitis.

关键词： Chronic Pancreatitis Ductal Epithelial Cells Islet Like Clusters Cell Differentiation

通过侧面接枝实现纳米棒在橡胶基体中的头尾相接组装

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通过侧面接枝实现纳米棒在橡胶基体中的头尾相接组装

Tailoring lifestyle programmes for diabetes prevention for US South Asians

第十四届中国橡胶基础研究研讨会

作者：陈玉龙徐前金杨福钱欣刘力刘军 venkat Ganesan 浙江工业大学北京化工大学德克萨斯大学奥斯汀分校

在橡胶基体中添加纳米粒子是改善或赋予橡胶材料特殊性能的关键。碳纳米管、金纳米棒等各向异性填料具有独特的力学及光电性能,其自组装形成的功能组装体能够展现出更加优异的整体协同性能,在橡胶纳米复合材料领域具有广泛而重要的应用... 详细信息

在橡胶基体中添加纳米粒子是改善或赋予橡胶材料特殊性能的关键。碳纳米管、金纳米棒等各向异性填料具有独特的力学及光电性能,其自组装形成的功能组装体能够展现出更加优异的整体协同性能,在橡胶纳米复合材料领域具有广泛而重要的应用前景。但是由于纳米棒的高长径比及强相互作用,通常会形成侧面对侧面(side-by-side)的平行聚集结构。本文提出,通过侧面接枝聚合物链去屏蔽纳米棒侧面之间的相互作用,使纳米棒能沿裸露的末端组装成头尾相接(end-to-end)结构。我们采用粗粒化分子动力学模拟去鉴定侧面接枝纳米棒发生头尾相接组装的条件,发现随着接枝链密度和长度的变化,纳米棒呈现出三种组装结构,即侧面对侧面、头尾相接及单粒子分散等结构,如图1所示。通过系统研究纳米棒周围接枝链构象特征,我们对其潜在的微观机理进行了深化认识。我们发现,纳米棒从侧面对侧面组装到头尾相接和单粒子分散结构的转变与接枝链构象的"蘑菇状"到"刷子状"转变(mushroom-to-brush transition)直接相关。在"刷子状"区(即高接枝密度下),纳米棒末端边缘侧面接枝链的扇出(splay out)效应将会遮住裸露的末端使其无法发生头尾组装。因此,只有在高接枝密度及低接枝链长度的条件下才能出现头尾连接的线性组装。总之,本文的研究将为实验上设计和制备具有头尾组装结构的橡胶/纳米棒复合材料提供思路和理论依据。

关键词：纳米棒接枝纳米复合自组装分子动力学模拟

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Family Medicine and Community Health 2020年第2期8卷 12-20页

作者： Mary Beth Weber Monique M Hennink K M venkat Narayan Hubert Department of Global Health Emory UniversityAtlantaGeorgiaUSA

Objective The purpose of this study was to develop and test the feasibility of a culturally tailored Diabetes Prevention Programme(DPP)for US South Asians,a large population with high diabetes *** The South Asian Health and Prevention Education(SHAPE)study included:(1)focus group discussions with South Asian adults to understand views of lifestyle behaviours and diabetes prevention;(2)modification of the US DPP for South Asians and(3)a pilot,pre-post study to test the feasibility and impact of delivering the culturally tailored *** The study was conducted in Atlanta,Georgia,*** group discussions and intervention classes were held at locations within the community(eg,South Asian restaurants,a public library,university classrooms,a South Asian owned physical therapy studio).Participants The focus group discussions(n=17 with 109 individuals)included adults aged 25 years of older who self-identified as South *** were stratified by age(25-40 years or older than 40 years)and *** SHAPE pilot study included 17(76.5%male with a mean age of 46.9±12 years)South Asian adults aged 25 years or older with pre-diabetes and body mass index(BMI)>22 kg/*** Formative data from 17 focus group discussions and a community board guided the modification of the DPP curriculum to reflect cultural food preferences and include tools to leverage social support,create a stronger foundation in exercise and overcome culturally specific *** SHAPE pilot study included 17 South Asian adults with pre-diabetes and BMI>22 kg/*** were positive changes in participants’weight,waist circumference,blood pressure,plasma lipids,HbA1c and other cardiometabolic markers postintervention and 55%of participants regressed to *** These results provide important information on the barriers faced by US South Asians in participating in‘standard’lifestyle change programs,indicate the feasibility of culturally tailored programmes and show p

关键词： prevention discussions overcome

CMOS图像传感器主导多种应用，提供巨大市场机遇

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今日电子 2011年第10期 51-54页

作者： venkat Puntambekar Dave Amey Narayan Purohit Aptina公司

在过去十年里，CMOS图像传感器技术经过连续改进和不断提高，已经使其从主要服务于低端市场转移到一些要求最苛刻的高性能应用。伴随着这种趋势，CMOS图像传感器已经开始主导图像传感器市场，并为原始设备制造商（0EM）实现差异化提供... 详细信息

在过去十年里，CMOS图像传感器技术经过连续改进和不断提高，已经使其从主要服务于低端市场转移到一些要求最苛刻的高性能应用。伴随着这种趋势，CMOS图像传感器已经开始主导图像传感器市场，并为原始设备制造商（0EM）实现差异化提供了很多机会。

关键词： CMOS图像传感器市场机遇性能应用原始设备制造商传感器技术低端市场差异化多机