65 resultados para Domain-specific analysis


Relevância:

80.00% 80.00%

Publicador:

Resumo:

The self-quotient image is a biologically inspired representation which has been proposed as an illumination invariant feature for automatic face recognition. Owing to the lack of strong domain specific assumptions underlying this representation, it can be readily extracted from raw images irrespective of the persons's pose, facial expression etc. What makes the self-quotient image additionally attractive is that it can be computed quickly and in a closed form using simple low-level image operations. However, it is generally accepted that the self-quotient is insufficiently robust to large illumination changes which is why it is mainly used in applications in which low precision is an acceptable compromise for high recall (e.g. retrieval systems). Yet, in this paper we demonstrate that the performance of this representation in challenging illuminations has been greatly underestimated. We show that its error rate can be reduced by over an order of magnitude, without any changes to the representation itself. Rather, we focus on the manner in which the dissimilarity between two self-quotient images is computed. By modelling the dominant sources of noise affecting the representation, we propose and evaluate a series of different dissimilarity measures, the best of which reduces the initial error rate of 63.0% down to only 5.7% on the notoriously challenging YaleB data set.

Relevância:

80.00% 80.00%

Publicador:

Resumo:

Objectives
To investigate associations between modest levels of total and domain-specific (commuting, other utility, recreational) cycling and mortality from all causes, cardiovascular disease and cancer.

Design
Population-based cohort study (European Prospective Investigation into Cancer and Nutrition study-Norfolk).

Setting
Participants were recruited from general practices in the east of England and attended health examinations between 1993 and 1997 and again between 1998 and 2000. At the first health assessment, participants reported their average weekly duration of cycling for all purposes using a simple measure of physical activity. At the second health assessment, participants reported a more detailed breakdown of their weekly cycling behaviour using the EPAQ2 physical activity questionnaire.

Participants
Adults aged 40–79 years at the first health assessment.

Primary outcome measure
All participants were followed for mortality (all-cause, cardiovascular and cancer) until March 2011.

Results
There were 22 450 participants with complete data at the first health assessment, of whom 4398 died during follow-up; and 13 346 participants with complete data at the second health assessment, of whom 1670 died during follow-up. Preliminary analyses using exposure data from the first health assessment showed that cycling for at least 60 min/week in total was associated with a 9% reduced risk of all-cause mortality (adjusted HR 0.91, 95% CI 0.84 to 0.99). Using the more precise measures of cycling available from the second health assessment, all types of cycling were associated with greater total moderate-to-vigorous physical activity; however, there was little evidence of an association between overall or domain-specific cycling and mortality.

Conclusions
Cycling, in particular for utility purposes, was associated with greater moderate-to-vigorous and total physical activity. While this study provides tentative evidence that modest levels of cycling may reduce the risk of mortality, further research is required to confirm how much cycling is sufficient to induce health benefits.

Relevância:

80.00% 80.00%

Publicador:

Resumo:

The research reported in this paper examined spoken mathematics in particular well-taught classrooms in Australia, China (both Shanghai and Hong Kong), Japan, Korea and the USA from the perspective of the distribution of responsibility for knowledge generation in order to identify similarities and differences in classroom practice and the implicit pedagogical principles that underlie those practices. The methodology of the Learner’s Perspective Study (LPS) documented the voicing of mathematical ideas in public discussion and in teacher-student conversations and the relative priority accorded by different teachers to student oral contributions to classroom activity. Significant differences were identified among the classrooms studied, challenging simplistic characterisations of ‘the Asian classroom’ as enacting a single pedagogy, and suggesting that, irrespective of cultural similarities, local pedagogies reflect very different assumptions about learning and instruction. We have employed spoken mathematical terms as a form of surrogate variable, possibly indicative of the location of the agency for knowledge generation in the various classrooms studied (but also of interest in itself). The analysis distinguished one classroom from another on the basis of “public oral interactivity” (the number of utterances in whole class and teacher-student interactions in each lesson) and “mathematical orality” (the frequency of occurrence of key mathematical terms in each lesson). Classrooms characterized by high public oral interactivity were not necessarily sites of high mathematical orality. In particular, the results suggest that one characteristic that might be identified with a national norm of practice could be the level of mathematical orality: relatively high mathematical orality characterising the mathematics classes in Shanghai with some consistency, while lessons in Seoul and Hong Kong consistently involved much less frequent spoken mathematical terms. The relative contributions of teacher and students to this spoken mathematics provided an indication of how the responsibility for knowledge generation was shared between teacher and student in those classrooms. Specific analysis of the patterns of interaction by which key mathematical terms were introduced or solicited revealed significant differences. It is suggested that the empirical investigation of mathematical orality and its likely connection to the distribution of the responsibility for knowledge generation are central to the development of any theory of mathematics instruction.

Relevância:

80.00% 80.00%

Publicador:

Resumo:

The recent wide adoption of electronic medical records (EMRs) presents great opportunities and challenges for data mining. The EMR data are largely temporal, often noisy, irregular and high dimensional. This paper constructs a novel ordinal regression framework for predicting medical risk stratification from EMR. First, a conceptual view of EMR as a temporal image is constructed to extract a diverse set of features. Second, ordinal modeling is applied for predicting cumulative or progressive risk. The challenges are building a transparent predictive model that works with a large number of weakly predictive features, and at the same time, is stable against resampling variations. Our solution employs sparsity methods that are stabilized through domain-specific feature interaction networks. We introduces two indices that measure the model stability against data resampling. Feature networks are used to generate two multivariate Gaussian priors with sparse precision matrices (the Laplacian and Random Walk). We apply the framework on a large short-term suicide risk prediction problem and demonstrate that our methods outperform clinicians to a large margin, discover suicide risk factors that conform with mental health knowledge, and produce models with enhanced stability. © 2014 Springer-Verlag London.

Relevância:

80.00% 80.00%

Publicador:

Resumo:

OBJECTIVE: Physical activity recommendations are beginning to address sedentary behaviors - time spent sitting. Environmental and policy initiatives for physical activity might assist in addressing sedentary behaviors, but sedentary-specific innovations may be required. This review synthesizes current evidence on associations of neighborhood environmental attributes with adults' sedentary behaviors. METHODS: A search was conducted using three electronic databases (PubMed, Web of Science, and Transport Research Information Services). Relevant articles were assessed for their eligibility for inclusion (English-language articles with a quantitative examination of associations of neighborhood environmental attributes with adults' sedentary behaviors). RESULTS: Within 17 studies meeting inclusion criteria, associations of environmental attributes with sedentary behaviors were examined in 89 instances. Significant associations were found in 28% (n=25) of them; however, non-significant associations were found in 56% (n=50) of these instances. The most consistent association was for lower levels of sedentary behavior among residents of urban compared to regional areas. CONCLUSIONS: There is a modest but mixed initial evidence in associations of neighborhood environmental attributes with adults' sedentary behaviors. A research agenda required for this emerging field should include the development of more relevant conceptual models, measuring domain-specific sedentary behavior objectively, examining environments in close vicinity of and a larger area around home, and the use of prospective designs.

Relevância:

80.00% 80.00%

Publicador:

Resumo:

When job applicants lie in job interviews, they can deprive a more honest candidate of a job and deprive an organisation of the best employees. To better understand job interview faking, the present study examined the effect of general dispositions and domain-specific beliefs on the intention to fake job interviews. A community sample of 313 participants completed measures of personality (i.e., extraversion, neuroticism, conscientiousness) and self-monitoring, and a domain-specific measure of beliefs about faking job interviews based on the theory of planned behaviour, which measured attitudes, subjective norms, and perceived behavioural control. Results indicated that the measure of attitudes was the strongest predictor of intention to fake. In line with the compatibility principle, the domain-specific measures based on the theory of planned behaviour correlated much more strongly with intentions to fake job interviews than did the general measures of personality or self-monitoring. Of the dispositional measures, lower conscientiousness, higher neuroticism, and higher self-monitoring was associated with greater intention to fake job interviews. The findings support a model whereby the effect of personality on intentions is partially mediated by domain-specific beliefs.

Relevância:

80.00% 80.00%

Publicador:

Resumo:

Modern IDEs provide limited support for developers when starting a new data-driven mobile app. App developers are currently required to write copious amounts of boilerplate code, scripts, organise complex directories, and author actual functionality. Although this scenario is ripe for automation, current tools are yet to address it adequately. In this paper we present RAPPT, a tool that generates the scaffolding of a mobile app based on a high level description specified in a Domain Specific Language (DSL). We demonstrate the feasibility of our approach by an example case study and feedback from a professional development team. Demo at: https://www.youtube.com/watch?v=ffquVgBYpLM.

Relevância:

80.00% 80.00%

Publicador:

Resumo:

Objective: We want to support enterprise service modelling and generation using a more end user-friendly metaphor than current approaches, which fail to scale to large organisations with key issues of "cobweb" and "labyrinth" problems and large numbers of hidden dependencies. Method: We present and evaluate an integrated visual approach for business process modelling using a novel tree-based overlay structure that effectively mitigate complexity problems. A tree-overlay based visual notation (EML) and its integrated support environment (MaramaEML) supplement and integrate with existing solutions. Complex business architectures are represented as service trees and business processes are modelled as process overlay sequences on the service trees. Results: MaramaEML integrates EML and BPMN to provide complementary, high-level business service modelling and supports automatic BPEL code generation from the graphical representations to realise web services implementing the specified processes. It facilitates generated service validation using an integrated LTSA checker and provides a distortion-based fisheye and zooming function to enhance complex diagram navigation. Evaluations of EML show its effectiveness. Conclusions: We have successfully developed and evaluated a novel tree-based metaphor for business process modelling and enterprise service generation. Practice implications: a more user-friendly modelling approach and support tool for business end users.

Relevância:

80.00% 80.00%

Publicador:

Resumo:

CONTEXT: Modifiable factors of health-related quality of life (HRQOL) are poorly described among children with advanced cancer. Symptom distress may be an important factor for intervention. OBJECTIVES: We aimed to describe patient-reported HRQOL and its relationship to symptom distress. METHODS: Prospective, longitudinal data from the multicenter Pediatric Quality of Life and Symptoms Technology study included primarily patient-reported symptom distress and HRQOL, measured at most weekly with the Memorial Symptoms Assessment Scale and Pediatric Quality of Life inventory, respectively. Associations were evaluated using linear mixed-effects models adjusting for sex, age, cancer type, intervention arm, treatment intensity, and time since disease progression. RESULTS: Of 104 enrolled patients, 49% were female, 89% were white, and median age was 12.6 years. Nine hundred and twenty surveys were completed over nine months of follow-up (84% by patients). The median total Pediatric Quality of Life score was 74 (interquartile range 63-87) and was "poor/fair" (e.g., <70) 38% of the time. "Poor/fair" categories were highest in physical (53%) and school (48%) compared to emotional (24%) and social (16%) subscores. Thirteen of 24 symptoms were independently associated with reductions in overall or domain-specific HRQOL. Patients commonly reported distress from two or more symptoms, corresponding to larger HRQOL score reductions. Neither cancer type, time since progression, treatment intensity, sex, nor age was associated with HRQOL scores in multivariable models. Among 25 children completing surveys during the last 12 weeks of life, 11 distressing symptoms were associated with reductions in HRQOL. CONCLUSION: Symptom distress is strongly associated with HRQOL. Future research should determine whether alleviating distressing symptoms improves HRQOL in children with advanced cancer.

Relevância:

80.00% 80.00%

Publicador:

Resumo:

Developing complex computational-intensiveand data-intensive scientific applications requires effectiveutilization of the computational power of the availablecomputing platforms including grids, clouds, clusters, multicoreand many-core processors, and graphical processingunits (GPUs). However, scientists who need to leverage suchplatforms are usually not parallel or distributed programmingexperts. Thus, they face numerous challenges whenimplementing and porting their software-based experimentaltools to such platforms. In this paper, we introduce asequential-to-parallel engineering approach to help scientistsin engineering their scientific applications. Our approach isbased on capturing sequential program details, plannedparallelization aspects, and program deployment details usinga set of domain-specific visual languages (DSVLs). Then, usingcode generation, we generate the corresponding parallelprogram using necessary parallel and distributedprogramming models (MPI, OpenCL, or OpenMP). Wesummarize three case studies (matrix multiplication, N-Bodysimulation, and signal processing) to evaluate our approach.

Relevância:

80.00% 80.00%

Publicador:

Resumo:

This paper demonstrates a multi-view framework for Rapid APPlication Tool (RAPPT). RAPPT enables rapid development of mobile applications. It employs a multilevel approach to mobile application development: a Domain Specific Visual Language to define the high level structure of mobile apps, a Domain Specific Textual Language to define behavioural concepts, and concrete source code for fine grained improvements.

Relevância:

80.00% 80.00%

Publicador:

Resumo:

Software environment emulation provides a means for simulating an operational environment of a system. This process involves approximation of systems’ external behaviors and their communications with a system to be tested in the environment. Development of such an environment is a tedious task and involves complex low level coding. Model driven engineering is an avenue to raise the level of abstraction beyond programming by specifying solution directly using problem domain concepts. In this paper we propose a novel domain-specific modeling tool to generate complex testing environments. Our tool employs a suite of domain-specific visual modeling languages for modelling emulation environment at a high level of abstraction. These high level specifications are then automatically transformed to runtimeenvironment for application integration testing, boosting development productivity and ease of use.

Relevância:

50.00% 50.00%

Publicador:

Resumo:

A key process in the lifecycle of the malaria parasite Plasmodium falciparum is the fast invasion of human erythrocytes. Entry into the host cell requires the apical membrane antigen 1 (AMA-1), a type I transmembrane protein located in the micronemes of the merozoite. Although AMA-1 is evolving into the leading blood-stage malaria vaccine candidate, its precise role in invasion is still unclear. We investigate AMA-1 function using live video microscopy in the absence and presence of an AMA-1 inhibitory peptide. This data reveals a crucial function of AMA-1 during the primary contact period upstream of the entry process at around the time of moving junction formation. We generate a Plasmodium falciparum cell line that expresses a functional GFP-tagged AMA-1. This allows the visualization of the dynamics of AMA-1 in live parasites. We functionally validate the ectopically expressed AMA-1 by establishing a complementation assay based on strain-specific inhibition. This method provides the basis for the functional analysis of essential genes that are refractory to any genetic manipulation. Using the complementation assay, we show that the cytoplasmic domain of AMA-1 is not required for correct trafficking and surface translocation but is essential for AMA-1 function. Although this function can be mimicked by the highly conserved cytoplasmic domains of P. vivax and P. berghei, the exchange with the heterologous domain of the microneme protein EBA-175 or the rhoptry protein Rh2b leads to a loss of function. We identify several residues in the cytoplasmic tail that are essential for AMA-1 function. We validate this data using additional transgenic parasite lines expressing AMA-1 mutants with TY1 epitopes. We show that the cytoplasmic domain of AMA-1 is phosphorylated. Mutational analysis suggests an important role for the phosphorylation in the invasion process, which might translate into novel therapeutic strategies.

Relevância:

50.00% 50.00%

Publicador:

Resumo:

The application of nucleic acid aptamers for the diagnosis and therapy of cancer stem cells (CSCs) is expanding. The current study truncated and probed various existing aptamers against CSC markers CD44, ABCG2 and CD133 in retinoblastoma (RB) primary cells, cell lines, a breast cancer cell line and MCF7-sphere. Truncated CD44 aptamer retained its specific binding to cancer cells, ABCG2+ve MCF7-spheres and CD133+ve RB cells. Similarly, ABCG2 and CD133 aptamers showed higher affinity to ABCG2+ve, CD133+ve cells than the negative population and cell lines. All aptamers appreciably reduced viability of up to 50% and 32% of the primary RB tumor cells and cell lines, respectively. Colony formation of MCF7, RB cell lines and MCF7-sphere growth were inhibited significantly. Structure prediction, simulation of CD133 extracellular domain 2 (ExD2) and A15 followed by docking to comprehend the potential interaction revealed hydrogen bonds and non bonded interactions between them. This information could be used to improve the A15 aptamer to gain more interactions with CD133. Thus approaches undertaken here can be applied universally for cell-specific targeting, and the aptamers studied against CSC markers deserve further in vivo studies.

Relevância:

40.00% 40.00%

Publicador:

Resumo:

Designing a successful web project requires understanding not only of its owner's business and technological needs, as well as having the substantial management and development experience, but it also depends on a thorough knowledge of the system's application domain and of other existing systems in the domain. In order to gather such domain knowledge, it is necessary to identify the nature of the proposed web services venture with regards to other similar services offered in the domain, the business setting of enterprises that initiate such ventures, the various types of customers involved, and how these factors translate into requirements. In this paper, we present an approach to studying the domain of web-enabled Human Resource and payroll services with the aim of attaining design knowledge that would ensure customer satisfaction and could eventually pave the way to the successful implementation of web-enabled services.