Página 1 dos resultados de 1413 itens digitais encontrados em 0.166 segundos

Web-assisted tobacco intervention in Portuguese : intentions to make behavioural changes and behavioural changes

Nunes, Luís Saboga
Fonte: Universidade Nova de Lisboa. Escola Nacional de Saúde Pública Publicador: Universidade Nova de Lisboa. Escola Nacional de Saúde Pública
Tipo: Tese de Doutorado
Publicado em //2011 ENG
Relevância na Pesquisa
55.47%
ABSTRACT - The problem of how to support “intentions to make behavioural changes” (IBC) and “behaviour changes” (BC) in smoking cessation when there is a scarcity of resources is a pressing issue in public health terms. The present research focuses on the use of information and communications technologies and their role in smoking cessation. It is developed in Portugal after the ratification of WHO Framework Convention on Tobacco Control (on 8 November 2005). The prevalence of smokers over fifteen years of age within the population stood at 20.9% (30.9% for men and 11.8% for women). While the strategy of helping people to quit smoking has been emphasised at National Health Service (NHS) level, the uptake of cessation assistance has exceeded the capacity of the service. This induced the search of new theoretical and practical venues to offer alternative options to people willing to stop smoking. Among these, the National Health Plan (NHP) of Portugal (2004-2010), identifies the use of information technologies in smoking cessation. eHealth and the importance of health literacy as a means of empowering people to make behavioural changes is recurrently considered an option worth investigating. The overall objective of this research is to understand...

Smoking and consistently high use of medical care among older HMO members.

Freeborn, D K; Mullooly, J P; Pope, C R; McFarland, B H
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
Publicado em /05/1990 EN
Relevância na Pesquisa
55.46%
Smoking behavior of consistently high and low users of medical care services were compared in two groups of older health maintenance organization (HMO) members continuously enrolled for five years and a subgroup who were continuously enrolled for 10 years. Smokers and former smokers, combined, were more likely than never-smokers to be consistently high users of ambulatory services (52 percent vs 34 percent in the five-year group, and 45 percent vs 30 percent in the 10-year group).

The role of the general practitioner in the community care of people with HIV infection and AIDS: a comparative study of high- and low-prevalence areas in England.

King, M; Petchey, R; Singh, S; Wright, L; Raab, J; Farnsworth, W; Williams, J; Friedli, K
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
Publicado em /05/1998 EN
Relevância na Pesquisa
45.55%
BACKGROUND: Policy for the care of people suffering from HIV and AIDS has changed over the past decade. Schemes for shared primary and secondary care have been met with varying success, and patients may be reluctant to become involved. No systematic evaluation comparing the views of primary care providers and users in areas of varying HIV prevalence has been published. AIM: To examine the role of general practice in areas of England with low and high human immunodeficiency virus (HIV) prevalence and to compare barriers to general practice care in each area. METHOD: We used focus groups, semistructured questionnaires and interviews in north London (high HIV prevalence) and Nottingham (low HIV prevalence). RESULTS: Four focus groups took place in London. A total of 411 general practitioners (GPs) in London and 405 in Nottingham replied to postal questionnaires. Overall, 121 primary care staff in 40 London practices and 26 staff in five Nottingham practices were interviewed. In all, 54 people infected with HIV were interviewed in London and 20 in Nottingham. Providers and users regarded the 24-hour availability and the familiar environment of general practice as its key assets. Lack of expertise and time were its disadvantages. Providers were concerned about inadequate communication with specialist services. Although providers were concerned about confidentiality...

The Topography of Poverty in the United States: A Spatial Analysis Using County-Level Data From the Community Health Status Indicators Project

Holt, James B
Fonte: Centers for Disease Control and Prevention Publicador: Centers for Disease Control and Prevention
Tipo: Artigo de Revista Científica
Publicado em 15/09/2007 EN
Relevância na Pesquisa
55.41%
Socioeconomic and health-related data at the county level are now available through the Community Health Status Indicators (CHSI) database. These data are useful for assessing the health of communities and regions. Users of the CHSI data can access online reports and an online mapping application for visualizing patterns in various community-related measures. It also is possible to download these data to conduct local analyses. This paper describes a spatial analysis of poverty in the United States at the county level for 2000. Spatial statistical techniques in a geographic information system were used to quantify significant spatial patterns, such as concentrated poverty rates and spatial outliers. The analysis revealed significant and stark patterns of poverty. A distinctive north–south demarcation of low versus high poverty concentrations was found, along with isolated pockets of high and low poverty within areas in which the predominant poverty rates were opposite. This pattern can be described as following a continental poverty divide. These insights can be useful in explicating the underlying processes involved in forming such spatial patterns that result in concentrated wealth and poverty. The spatial analytic techniques are broadly applicable to socioeconomic and health-related data and can provide important information about the spatial structure of datasets...

High Theta and Low Alpha Powers May Be Indicative of BCI-Illiteracy in Motor Imagery

Ahn, Minkyu; Cho, Hohyun; Ahn, Sangtae; Jun, Sung Chan
Fonte: Public Library of Science Publicador: Public Library of Science
Tipo: Artigo de Revista Científica
Publicado em 22/11/2013 EN
Relevância na Pesquisa
45.51%
In most brain computer interface (BCI) systems, some target users have significant difficulty in using BCI systems. Such target users are called ‘BCI-illiterate’. This phenomenon has been poorly investigated, and a clear understanding of the BCI-illiteracy mechanism or a solution to this problem has not been reported to date. In this study, we sought to demonstrate the neurophysiological differences between two groups (literate, illiterate) with a total of 52 subjects. We investigated recordings under non-task related state (NTS) which is collected during subject is relaxed with eyes open. We found that high theta and low alpha waves were noticeable in the BCI-illiterate relative to the BCI-literate people. Furthermore, these high theta and low alpha wave patterns were preserved across different mental states, such as NTS, resting before motor imagery (MI), and MI states, even though the spatial distribution of both BCI-illiterate and BCI-literate groups did not differ. From these findings, an effective strategy for pre-screening subjects for BCI illiteracy has been determined, and a performance factor that reflects potential user performance has been proposed using a simple combination of band powers. Our proposed performance factor gave an r = 0.59 (r2 = 0.34) in a correlation analysis with BCI performance and yielded as much as r = 0.70 (r2 = 0.50) when seven outliers were rejected during the evaluation of whole data (N = 61)...

Echographic and Kinetic Changes in the Shoulder Joint after Manual Wheelchair Propulsion Under Two Different Workload Settings

Gil-Agudo, Ángel; Solís-Mozos, Marta; Crespo-Ruiz, Beatriz; del-Ama Eng, Antonio J.; Pérez-Rizo, Enrique; Segura-Fragoso, Antonio; Jiménez-Díaz, Fernando
Fonte: Frontiers Media S.A. Publicador: Frontiers Media S.A.
Tipo: Artigo de Revista Científica
Publicado em 23/12/2014 EN
Relevância na Pesquisa
55.45%
Manual wheelchair users with spinal cord injury (SCI) have a high prevalence of shoulder pain due to the use of the upper extremity for independent mobility, transfers, and other activities of daily living. Indeed, shoulder pain dramatically affects quality of life of these individuals. There is limited evidence obtained through radiographic techniques of a relationship between the forces acting on the shoulder during different propulsion conditions and shoulder pathologies. Today, ultrasound is widely accepted as a precise tool in diagnosis, displaying particularly effectiveness in screening the shoulder rotator cuff. Thus, we set out to perform an ultrasound-based study of the acute changes to the shoulder soft tissues after propelling a manual wheelchair in two workload settings. Shoulder joint kinetics was recorded from 14 manual wheelchair users with SCI while they performed high- and low-intensity wheelchair propulsion tests (constant and incremental). Shoulder joint forces and moments were obtained from inverse dynamic methods, and ultrasound screening of the shoulder was performed before and immediately after the test. Kinetic changes were more relevant after the most intensive task, showing the significance of high-intensity activity...

Dynamic power allocation and routing for satellite and wireless networks with time varying channels

Neely, Michael J. (Michael James), 1975-
Fonte: Massachusetts Institute of Technology Publicador: Massachusetts Institute of Technology
Tipo: Tese de Doutorado Formato: 295 p.; 1502113 bytes; 1500707 bytes; application/pdf; application/pdf
ENG
Relevância na Pesquisa
55.37%
Satellite and wireless networks operate over time varying channels that depend on attenuation conditions, power allocation decisions, and inter-channel interference. In order to reliably integrate these systems into a high speed data network and meet the increasing demand for high throughput and low delay, it is necessary to develop efficient network layer strategies that fully utilize the physical layer capabilities of each network element. In this thesis, we develop the notion of network layer capacity and describe capacity achieving power allocation and routing algorithms for general networks with wireless links and adaptive transmission rates. Fundamental issues of delay, throughput optimality, fairness, implementation complexity, and robustness to time varying channel conditions and changing user demands are discussed. Analysis is performed at the packet level and fully considers the queueing dynamics in systems with arbitrary, potentially bursty, arrival processes. Applications of this research are examined for the specific cases of satellite networks and ad-hoc wireless networks. Indeed, in Chapter 3 we consider a multi-beam satellite downlink and develop a dynamic power allocation algorithm that allocates power to each link in reaction to queue backlog and current channel conditions. The algorithm operates without knowledge of the arriving traffic or channel statistics...

Options to Increase Access to Telecommunications Services in Rural and Low-Income Areas

Muente-Kunigami, Arturo; Navas-Sabater, Juan
Fonte: World Bank Publicador: World Bank
Relevância na Pesquisa
55.48%
Recent evidence suggests that increasing overall service coverage and promoting access to telecommunications services have a high economic benefit. Overall, it is estimated that a ten percent increase in mobile telephony penetration could increase economic growth by 0.81 percent in developing countries, whereas a ten percent increase in broadband penetration could increase economic growth by 1.4 percent. In rural and low-income areas in particular, not only do basic telephony services and broadband access allow population to connect with relatives and friends, but they have also introduced a dramatic increase in productivity and in many cases have become the only way for small and medium enterprises in rural areas to access national and, in some cases, global markets. Moreover, the impact of access to telecommunications in rural areas on health, education, disaster management, and local governments has allowed better and more rapid responses, improved coordination, and more effective public management. It is therefore worthwhile to take a second look at all possible policy options...

The Potential Demand for and Strategic Use of an HIV-1 Vaccine in Southern India

Seshadri, Shreelata Rao; Subramaniyam, P.; Jha, Prabhat
Fonte: World Bank, Washington, DC Publicador: World Bank, Washington, DC
EN_US
Relevância na Pesquisa
55.46%
Even a modestly effective HIV-1 vaccine would be highly useful in India and could avoid millions of deaths. How should such a vaccine be introduced? Based on evidence of adoption of other vaccines in India, current levels of spending on them and coverage of prevention programs targeting both high- and low-risk groups, Seshadri, Subramaniyam, and Jha assess the potential demand for and strategic use of an HIV-1 vaccine in the four southern Indian states of Andhra Pradesh, Karnataka, Maharashtra, and Tamil Nadu. The authors also discuss potential strategies for delivery of the vaccine, prioritization for vaccination, and the political economy of such a vaccine in India. Assuming a vaccine cost of $10 a dose and including estimated delivery costs, the total cost of vaccinating 21.6 million adolescents 11-14 years of age and 1 percent of adults would be Rs. 12.25 billion (US$ 245 million). To maintain the vaccination rate in the 11-14 year old cohort, an additional 6.77 million in that age range would have to be vaccinated each year...

Results in the Latin America and Caribbean Region

World Bank
Fonte: Washington, DC Publicador: Washington, DC
EN_US
Relevância na Pesquisa
45.51%
A focus on development results is at the heart of the Latin America and Caribbean Region s approach to delivering programs and policy advice with partners in middle-income and low income countries alike. Through knowledge, convening activities, and financial services we strive to help people across the region create better opportunities and build a better future for themselves, their families and their country. Documenting, measuring and evaluating results of what we do, helps us and our partners to engage more effectively, learn from our experiences and apply lessons to the design and implementation of future interventions. This collection of result stories shows our continuous efforts to adopt and integrate technical analysis, timely policy advice, and a variety of financial instruments into programs that are aligned with client priorities. Results show the increased demand and the effectiveness of peer-to-peer learning, have led to a scaling up our support for South-South exchange activities and the use our convening power to support successful partnerships and mobilize additional resources to finance development work.

The Widening Information Gap between High and Low Education Groups: Knowledge Acquisition from Online vs. Print News

Yang, JungAe
Fonte: [Bloomington, Ind.] : Indiana University Publicador: [Bloomington, Ind.] : Indiana University
Tipo: Doctoral Dissertation
EN
Relevância na Pesquisa
65.56%
Thesis (Ph.D.) - Indiana University, Mass Communications/Telecommunications, 2008; The primary purpose of this study is to empirically investigate the potentially widening gap in information acquisition across different educational groups, related to traditional print versus online news formats. Newspaper readership is declining and simultaneously the number of online news users is growing. In democratic societies the ability of new media formats to deliver cognitively accessible information to all citizens is indeed a pressing issue. This dissertation adopted the strengths of both survey and experimental traditions of knowledge gap research. Specifically, this study follows in the survey research tradition by emphasizing social structural aspects of the knowledge gap phenomenon. At the same time, this research used controlled experimental procedures and an assortment of memory measures to rigorously investigate the formation of knowledge gaps. The experimental procedure also allowed for focus on a much neglected dimension of knowledge gain, namely news exposure preferences (public affairs vs. entertainment) of citizens. To this effect, news exposure was examined using a behavioral measure, which is more rigorous than the heavily relied on self-report measure. The findings show strong support of the existence of knowledge gaps. First...

Resource allocation and scheduling for communication satellites with advanced transmission antennas

Choi, Jihwan Patrick, 1975-
Fonte: Massachusetts Institute of Technology Publicador: Massachusetts Institute of Technology
Tipo: Tese de Doutorado Formato: 180 p.
ENG
Relevância na Pesquisa
45.5%
For multimedia and other data services over satellite networks, the efficient management of scarce satellite communication resources is critical for the economic competitiveness of the medium. To support a broad spectrum of users with small terminals at high data rates, narrow transmit spotbeams from the satellite must be used. Since satellite on-board resources are too expensive to illuminate all of the spotbeam-coverage cells within the satellite service area, an optimized method of agile antenna gain patterning and beam scheduling is required to greatly improve the efficiency of transmission and power management. In this thesis, we jointly optimize resource allocation/scheduling, congestion control and antenna gain patterning for communication satellites with advanced transmission antennas. Then, we develop a low-complexity on-line algorithm that considers channel conditions, interference and average delay constraints, and approaches the theoretical steady-state limit. We introduce optimized beam profiling based on traffic demand and channel conditions over satellite downlinks, which can achieve a substantial power gain and reasonable proportional fairness. We show that a modest number of active parallel beams are sufficient to cover many cells efficiently with dynamic capacity allocation.; (cont.) Next...

Sound localization and interaural time sensitivity with bilateral cochlear implants

Poon, Becky Bikkei
Fonte: Massachusetts Institute of Technology Publicador: Massachusetts Institute of Technology
Tipo: Tese de Doutorado Formato: 170 p.
ENG
Relevância na Pesquisa
45.5%
Bilateral cochlear implantation is becoming more common as clinicians attempt to provide better sound-source localization and speech reception in noise for cochlear implant (CI) users. While some improvement over the abilities of monolateral implantees has been documented, bilateral performance for CI users is far from that achieved with normal hearing. Identifying factors that limit bilateral performance has been difficult because little is understood about CI listeners' localization abilities, their sensitivity to interaural cues, and the relationships between them. To better understand bilateral electric hearing, five bilateral CI users' abilities to locate sound sources and their sensitivities to interaural time difference (ITD) were studied in this thesis. Unlike past studies, monolateral and bilateral performance was recorded before and after exposure to daily, bilateral-CI listening using constant- and roving-level stimuli. For constant-level stimuli, increasing bilateral-listening experience improved all subjects' bilateral performance but degraded two subjects' monolateral performance. Using roving-level stimuli, increasing bilateral-listening experience also improved bilateral performance but did not alter monolateral performance.; (cont.) Our results show that depending on the method of evaluation...

Classify Sina Weibo users into High or Low happiness Groups Using Linguistic and Behavior Features

Wang, Jingying; Liu, Tianli; Zhu, Tingshao; Zhang, Lei; Hao, Bibo; Chen, Zhenxiang
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Relevância na Pesquisa
65.55%
It's of great importance to measure happiness of social network users, but the existing method based on questionnaires suffers from high costs and low efficiency. This paper aims at identifying social network users' happiness level based on their Web behavior. We recruited 548 participants to fill in the Oxford Happiness Inventory (OHI) and divided them into two groups with high/low OHI score. We downloaded each Weibo user's data by calling API, and extracted 103 linguistic and behavior features. 24 features are identified with significant difference between high and low happiness groups. We trained a Decision Tree on these 24 features to make the prediction of high/low happiness group. The decision tree can be used to identify happiness level of any new social network user based on linguistic and behavior features. The Decision Tree can achieve 67.7% on precision. Although the capability of our Decision Tree is not ideal, classifying happiness via linguistic and behavior features on the Internet is proved to be feasible.; Comment: 12 pages, 5 tables, 1 figures, typo fixed, the indexs in table 2 revised, four authors added

Emission line - radio correlation for Low Luminosity Compact sources. Evolution schemes

Kunert-Bajraszewska, M.; Labiano, A.; Gawronski, M. P.
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 29/06/2011
Relevância na Pesquisa
55.4%
We present radio and optical analysis of a sample of Low Luminosity Compact (LLC) objects, selected from FIRST survey and observed with MERLIN at L-band and C-band. The main criterion used for selection was luminosity of the objects and approximately one third of the CSS sources from the new sample have a value of radio luminosity comparable to FR\,Is.The analysis of a radio properties of LLC sources show they occupy the space in radio power versus linear size diagram below the main evolutionary path of radio objects. We suggest that many of them might be short-lived objects, and their radio emission may be disrupted several times before becoming FR\,IIs. The optical analysis of the LLC sources were made based on the available SDSS images and spectra. We have classified the sources as high and low excitation galaxies (HEG and LEG, respectively). The optical and radio properties of the LLC sample are in general consistent with brighter CSSs and large-scale radio sources. However, when LLC are added to the other samples, HEG and LEG seem to follow independent, parallel evolutionary tracks. LLC and luminous CSS behave like FR\,II sources, while FR\,I seem to belong to a different group of objects, concerning ionization mechanisms. Based on our results...

User profile based proportional share scheduling and mac protocol for manets

Monisha, J. Hannah; Uthariaraj, V. Rhymend
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 08/02/2012
Relevância na Pesquisa
45.5%
Quality of Service(QoS) in Mobile Ad Hoc Networks (MANETs) though a challenge, becomes a necessity because of its applications in critical scenarios. Providing QoS for users belonging to various profiles and playing different roles, becomes the need of the hour. In this paper, we propose proportional share scheduling and MAC protocol (PS2-MAC) model. It classifies users based on their profile as High Profiled users (HP), Medium Profiled users (MP) and Low profiled users (LP) and assigns proportional weights. Service Differentiation for these three service classes is achieved through, rationed dequeuing algorithm, variable inter frame space, proportionate prioritized backoff timers and enhanced RTS/CTS control packets. Differentiated services is simulated in ns2 and results show that 9.5% control overhead is reduced in our proposed scheme than the existing scheme and results also justify that, differentiated services have been achieved for the different profiles of users with proportionate shares and thereby reducing starvation.

An effective single-hop distributed hash table with high lookup performance and low traffic overhead

Monnerat, Luiz; Amorim, Claudio L.
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 29/08/2014
Relevância na Pesquisa
55.41%
Distributed Hash Tables (DHTs) have been used in several applications, but most DHTs have opted to solve lookups with multiple hops, to minimize bandwidth costs while sacrificing lookup latency. This paper presents D1HT, an original DHT which has a peer-to-peer and self-organizing architecture and maximizes lookup performance with reasonable maintenance traffic, and a Quarantine mechanism to reduce overheads caused by volatile peers. We implemented both D1HT and a prominent single-hop DHT, and we performed an extensive and highly representative DHT experimental comparison, followed by complementary analytical studies. In comparison with current single-hop DHTs, our results showed that D1HT consistently had the lowest bandwidth requirements, with typical reductions of up to one order of magnitude, and that D1HT could be used even in popular Internet applications with millions of users. In addition, we ran the first latency experiments comparing DHTs to directory servers, which revealed that D1HT can achieve latencies equivalent to or better than a directory server, and confirmed its greater scalability properties. Overall, our extensive set of results allowed us to conclude that D1HT can provide a very effective solution for a broad range of environments...

Decoherence, tunneling and noise-activation in a double-potential well at high and zero temperature

Antunes, Nuno D.; Lombardo, Fernando C.; Monteoliva, Diana; Villar, Paula I.
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Relevância na Pesquisa
55.38%
We study the effects of the environment on tunneling in an open system described by a static double-well potential. We describe the evolution of a quantum state localized in one of the minima of the potential at $t=0$, both in the limits of high and zero environment temperature. We show that the evolution of the system can be summarized in terms of three main physical phenomena, namely decoherence, quantum tunneling and noise-induced activation, and we obtain analytical estimates for the corresponding time-scales. These analytical predictions are confirmed by large-scale numerical simulations, providing a detailed picture of the main stages of the evolution and of the relevant dynamical processes.; Comment: Version to appear in Phys. Rev. E. 15 pages, 12 figures (low quality due to upload size limitations). Good quality figures in a pdf file can be downloaded from http://www.df.uba.ar/users/lombardo/tunnel

Conflict and Computation on Wikipedia: a Finite-State Machine Analysis of Editor Interactions

DeDeo, Simon
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 14/12/2015
Relevância na Pesquisa
55.41%
What is the boundary between a vigorous argument and a breakdown of relations? What drives a group of individuals across it? Taking Wikipedia as a test case, we use a hidden Markov model to approximate the computational structure and social grammar of more than a decade of cooperation and conflict among its editors. Across a wide range of pages, we discover a bursty war/peace structure where the systems can become trapped---sometimes for months---in a computational subspace associated with high levels of rapid-fire conflict. Distinct patterns of behavior sustain the low-conflict subspace, including tit-for-tat reversion. While a fraction of the transitions between these subspaces are associated with top-down actions taken by administrators, the effects are weak and of uncertain valence. Surprisingly, we find no statistical signal that transitions are associated with the appearance of particularly anti-social users, and only weak association with significant news events outside the system. The majority of transitions between high and low conflict states appear to be driven by decentralized processes with no clear locus of control. Our results show how, in a modern sociotechnical system, memory of conflict is delocalized, and conflict management is a bottom-up process. It suggests that policy-makers may be limited in their ability to manage conflict...

Enhancing the use of internet banking in an emerging market

Nel,Jacques; Boshoff,Christo
Fonte: South African Journal of Economic and Management Sciences Publicador: South African Journal of Economic and Management Sciences
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/01/2014 EN
Relevância na Pesquisa
65.42%
Electronic banking services such as internet banking offer bank clients substantial benefits over traditional banking channels. Although internet banking has been around for many years, increasing the use of the service by bank clients remains a priority for many managers of internet banking services. To address this managerial concern, the study investigates the factors that contribute to the enhanced use of internet banking by bank clients. Based on a literature review, internet-banking factors that could influence bank clients' actual use of internet banking were identified. Data were collected from 1 156 users of internet banking. The results of the study showed that two factors influence internet banking usage, namely internet banking facilitating conditions and internet banking risk beliefs. The more favourable internet banking facilitating conditions are perceived to be, the more likely bank clients are to increase their use of internet banking. On the other hand, the greater the perceived risks associated with internet banking, the less the chances are that clients will do their banking through the internet. On the basis of these results, recommendations are provided to enhance the use of internet banking.