Search

n/a

n/a

n/a

n/a

n/a

n/a

n/a

In this paper, we mine and learn to predict how similar a pair of users' interests towards videos are, based on demographic (age, gender and location) and social (friendship, interaction and group membership) information of these users. We use the video access patterns of active users as ground truth (a form of benchmark). We adopt tag-based user profiling to establish this ground truth, and justify why it is used instead of video-based methods, or many latent topic models such as LDA and Collaborative Filtering approaches. We then show the effectiveness of the different demographic and social features, and their combinations and derivatives, in predicting user interest similarity, based on different machine-learning methods for combining multiple features. We propose a hybrid tree-encoded linear model for combining the features, and show that it out-performs other linear and treebased models. Our methods can be used to predict user interest similarity when the ground-truth is not available, e.g. for new users, or inactive users whose interests may have changed from old access data, and is useful for video recommendation. Our study is based on a rich dataset from Tencent, a popular service provider of social networks, video services, and various other services in China.

n/a

N/A

BackgroundThe Carotid Revascularization Endarterectomy Versus Stenting Trial (CREST) is a multicenter randomized trial of stenting versus endarterectomy in patients with symptomatic and asymptomatic carotid disease. This study assesses management of vascular risk factors.Methods and ResultsManagement was provided by the patient's physician, with biannual monitoring results collected by the local site. Therapeutic targets were low‐density lipoprotein, cholesterol

The transmembrane protein tyrosine phosphatase CD45 is expressed in multiple isoforms as a result of alternative splicing of variable exons encoding the extracellular domain. CD45 expression is critical for T cell development, and thymocyte maturation is blocked at the immature CD4+ CD8+ double-positive stage in CD45 gene-deficient (CD45 -/-) mice. Moreover, splicing of variable CD45 exons changes during thymocyte selection. To test the role of CD45 extracellular splice variants in T cell selection and development, we introduced CD45RO (a low-m.w. splice variant lacking exons 4, 5, and 6) and CD45ABC (a high-m.w. isoform containing all exons) transgenes under the control of a thymocyte-specific promoter into a CD45 -/- background, generating CD45RO transgene-positive CD45 -/- (CD45RO) and CD45ABC transgene-positive CD45 -/- (CD45ABC) mice. We demonstrate that both CD45 splice isoforms can rescue development of CD4+ and CD8+ TCR-alphabeta+ thymocytes. Neither CD45 isoform rescued positive selection of H-Y TCR transgene thymocytes, and these cells were blocked at a HSA(high) CD69- CD5(low) stage of development. Peripheral T cells from CD45RO and CD45ABC mice proliferated in response to allogeneic stimulator cells and anti-CD3epsilon cross-linking. However, only CD45RO mice, not CD45ABC mice, generated cytotoxic T cell responses and neutralizing, Th cell-dependent IgG Abs after viral infections. In addition, we show that T cells from CD45RO and CD45ABC mice accumulate in lymph nodes but not in the spleen, liver, or skin, indicating that the CD45 phosphatase may control the homing behavior and trafficking of T cells.

28th European Photovoltaic Solar Energy Conference and Exhibition; 2029-2033, DC magnetron sputtered Indium-Tin-Oxide (ITO) thin films were produced using state of the art high density rotary sintered ceramic ITO targets which yield uniform large area coatings. Deposition parameters have been chosen in order to fulfill the restrictions imposed by heterojunction a-Si/c-Si solar cells. Because of the pressure in the solar industry on manufacturing costs, rotary ITO sputtering targets which offer the potential to improve target utilization by a factor of 2.5, and associated overall coating cost improvements by 25-40 %, have been the focus of this study. A direct comparison of electrical and optical performance of ITO thin films produced from ceramic sputtering targets with SnO2 concentrations of 0, 3, 5 and 10 wt% is made in this paper. To our knowledge this is the first time the electro-optical performance of thin films produced from ceramic ITO sputtering targets with the above mentioned compositions and using identical industrial scale deposition conditions have been directly compared using typical heterojunction a-Si/c-Si cell parameters. Electrical Hall properties are compared with optical absorption curves in the visible and near infrared (NIR) for depositions with various Ar, O2 and H2 gas mixtures as a function of SnO2 concentration to identify the most suitable grade for a heterojunction a-Si/c-Si cell application. It was found that Sn- doped ITO containing 3 wt% SnO2 is the best alternative for replacing ITO-90/10 because of its superior optical characteristics at an acceptable conductivity, when using Ar/H2-Ar/O2 gas mixture during the deposition process.

27th European Photovoltaic Solar Energy Conference and Exhibition; 2079-2082, ITO is the front transparent conductive oxide (TCO) of choice for hetero-junction a-Si:H/c-Si solar cells because of its excellent combination of high electrical conductivity, good transparency in the visible part of the solar spectrum, and high work function. Unfortunately, the industrially established, DC magnetron sputtered, standard ITO grade, produced using a target with 10wt% SnO2, has certain drawbacks. Its low resistivity is mainly due to a relatively high free charge carrier concentration (FCC), up to 1.2E+21 cm-3. Consequently, it displays an increased absorption of photons at a wavelength above 900 nm due to free electrons. Additionally, because of the associated decrease in refractive index, a higher fraction of the incident light is reflected away from the silicon wafer. This results in significant optical losses in the NIR portion of the spectrum. Several publications exist which explore hydrogenated indium oxide (In2O3:H), a thin film with a much lower FCC and a very high carrier mobility (up to a factor of 2.5 higher), as an alternative for standard ITO. Pure In2O3 ceramic targets are rather brittle, however, hence more difficult to manufacture. Currently this composition is only available in a planar format so the cost effective mass production of In2O3:H thin films becomes questionable. This work explores the potential of ITO with lower Sn doping content (3 wt% of SnO2 in the ceramic target) as an alternative to the standard ITO (90/10). This material can still be produced as rotary targets which enables deposition of equivalent thickness coatings at a much lower cost. The main focus of this paper is a comparison of the electro-optical properties of thin films prepared by DC magnetron sputtering with sintered ceramic ITO rotary targets having various SnO2 concentrations.

A sharing community prospers when participation and contribution are both high. We suggest the two, while being related decisions every peer makes, should be given separate rational bases. Considered as such, a basic issue is the viability of club formation, which necessitates the modelling of two major sources of heterogeneity, namely, peers and shared content. This viability perspective clearly explains why rational peers contribute (or free-ride when they don't) and how their collective action determines viability as well as the size of the club formed. It also exposes another fundamental source of limitation to club formation apart from free-riding, in the community structure in terms of the relation between peers' interest (demand) and sharing (supply)., accepted in WINE2005, Hong Kong, December 15-17, 2005

File-sharing systems, like many online and traditional information sharing communities (e.g. newsgroups, BBS, forums, interest clubs), are dynamical systems in nature. As peers get in and out of the system, the information content made available by the prevailing membership varies continually in amount as well as composition, which in turn affects all peers' join/leave decisions. As a result, the dynamics of membership and information content are strongly coupled, suggesting interesting issues about growth, sustenance and stability. In this paper, we propose to study such communities with a simple statistical model of an information sharing club. Carrying their private payloads of information goods as potential supply to the club, peers join or leave on the basis of whether the information they demand is currently available. Information goods are chunked and typed, as in a file sharing system where peers contribute different files, or a forum where messages are grouped by topics or threads. Peers' demand and supply are then characterized by statistical distributions over the type domain. This model reveals interesting critical behaviour with multiple equilibria. A sharp growth threshold is derived: the club may grow towards a sustainable equilibrium only if the value of an order parameter is above the threshold, or shrink to emptiness otherwise. The order parameter is composite and comprises the peer population size, the level of their contributed supply, the club's efficiency in information search, the spread of supply and demand over the type domain, as well as the goodness of match between them., accepted in International Symposium on Computer Performance, Modeling, Measurements and Evaluation, Juan-les-Pins, France, October-2005

Widespread use of computer networks and the use of varied technology for the interconnection of computers has made congestion a significant problem. In this report, we summarize our research on congestion avoidance. We compare the concept of congestion avoidance with that of congestion control. Briefly, congestion control is a recovery mechanism, while congestion avoidance is a prevention mechanism. A congestion control scheme helps the network to recover from the congestion state while a congestion avoidance scheme allows a network to operate in the region of low delay and high throughput with minimal queuing, thereby preventing it from entering the congested state in which packets are lost due to buffer shortage. A number of possible alternatives for congestion avoidance were identified. From these alternatives we selected one called the binary feedback scheme in which the network uses a single bit in the network layer header to feed back the congestion information to its users, which then increase or decrease their load to make optimal use of the resources. The concept of global optimality in a distributed system is defined in terms of efficiency and fairness such that they can be independently quantified and apply to any number of resources and users. The proposed scheme has been simulated and shown to be globally efficient, fair, responsive, convergent, robust, distributed, and configuration-independent., DEC-TR-506, reprinted in C. Partridge, Ed., "Innovations in Internetworking," published by Artech House, October 1988

Fairness is an important performance criterion in all resource allocation schemes, including those in distributed computer systems. However, it is often specified only qualitatively. The quantitative measures proposed in the literature are either too specific to a particular application, or suffer from some undesirable characteristics. In this paper, we have introduced a quantitative measure called Indiex of FRairness. The index is applicable to any resource sharing or allocation problem. It is independent of the amount of the resource. The fairness index always lies between 0 and 1. This boundedness aids intuitive understanding of the fairness index. For example, a distribution algorithm with a fairness of 0.10 means that it is unfair to 90% of the users. Also, the discrimination index can be defined as 1 - fairness index., Comment: DEC Research Report TR-301, September 1984

The 18th Canadian Waste Management Conference: Winnipeg, Manitoba: October 21-24, 1996

Objective. —To determine prevalence of dementia and its subtypes in Japanese-American men and compare these findings with rates reported for populations in Japan and elsewhere. Design and Setting. —The Honolulu Heart Program is a prospective populationbased study of cardiovascular disease established in 1965. Prevalence estimates were computed from cases identified at the 1991 to 1993 examination. Cognitive performance was assessed using standardized methods, instruments, and diagnostic criteria. Participants. —Subjects were 3734 Japanese-American men (80% of surviving cohort) aged 71 through 93 years, living in the community or in institutions. Main Outcome Measures. —Age-specific, age-standardized, and cohort prevalence estimates were computed for dementia (all cause) defined by 2 sets of diagnostic criteria and 4 levels of severity. Prevalence levels for Alzheimer disease and vascular dementia were also estimated. Results. —Dementia prevalence byDiagnostic and Statistical Manual of Mental Disorders, Third Edition, Revisedranged from 2.1% in men aged 71 through 74 years to 33.4% in men aged 85 through 93 years. Age-standardized prevalence was 7.6%. Prevalence estimates for the cohort were 9.3% for dementia (all cause), 5.4% for Alzheimer disease (primary or contributing), and 4.2% for vascular dementia (primary or contributing). More than 1 possible cause was found in 26% of cases. The Alzheimer disease/vascular dementia ratio was 1.5 for cases attributed primarily to Alzheimer disease or vascular dementia. Conclusions. —Prevalence of Alzheimer disease in older Japanese-American men in Hawaii appears to be higher than in Japan but similar to European-ancestry populations. Prevalence of vascular dementia appears to be only slightly lower than in Japan, but higher than in European-ancestry populations. Further cross-national research with emphasis on standardized diagnostic methods is needed.

Activated neutrophils (ANs) are known to release reactive oxygen species that may cause oxidative damage to surrounding tissues. We determined if ANs could induce lipid peroxidation (LP) in human red cells and investigated the mechanism involved in this interaction. We studied neonatal glucose-6-phosphate dehydrogenase (G6PD) deficient, and sickle red cells, since each of these are known to be susceptible to oxidant injury. Neutrophils were isolated from whole blood and activated by incubation with opsonized zymosan. Mixtures of such neutrophils and red cells at a ratio of 1:100 were incubated for two hours at 37 degrees C, after which the malonyldialdehyde content in red cells was measured as an index of LP. All red cells underwent LP after AN treatment, and the degree of LP was proportional to the amount of AN in the mixture. Superoxide dismutase and catalase partially inhibited LP. When compared to normal red cells, only sickle cells demonstrated a significant increase in AN-mediated LP. Conversion of hemoglobin to carboxy-hemoglobin increased AN-mediated LP, whereas conversion to met- hemoglobin decreased AN-mediated LP. The protective effect of met- hemoglobin on LP was less in sickle cells than in normal cells. We conclude that AN can induce LP in red cells in vitro and that sickle cells are more susceptible to this process than normal cells. Hemoglobin can serve as an electron trap and protect the cell against peroxidative damage, but this mechanism is impaired in sickle cells. We speculate that the pathogenesis of hemolysis associated with infectious disease may include AN-induced red cell LP.