974 resultados para head-group


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Background The risk factors and co-factors for sporadic childhood BL are unknown. We investigated demographic and age-specific characteristics of childhood BL (0–14 years) in the U.S. Procedure BL age-standardized incidence rates (2000 U.S. standard population), were calculated using data obtained from 12 registries in the NCI’s Surveillance, Epidemiology, and End Results program for cases diagnosed from 1992 through 2005. Incidence rate ratios and 95% confidence intervals (95% CI) were calculated by gender, age-group, race, ethnicity, calendar-year period, and registry. Results Of 296 cases identified, 56% were diagnosed in lymph nodes, 21% in abdominal organs, not including retroperitoneal lymph nodes, 14% were Burkitt cell leukemia, and 9% on face/head structures. The male-to-female case ratio was highest for facial/head tumors (25:1) and lowest for Burkitt cell leukemia (1.6:1). BL incidence rate was 2.5 (95% CI 2.3–2.8) cases per million person-years and was higher among boys than girls (3.9 vs. 1.1, p<0.001) and higher among Whites and Asians/Pacific Islanders than among Blacks (2.8 and 2.9 vs.1.2, respectively, p<0.001). By ethnicity, BL incidence was higher among non-Hispanic Whites than Hispanic Whites (3.2 vs. 2.0, p=0.002). Age-specific incidence rate for BL peaked by age 3–5 years (3.4 cases per million), then stabilized or declined with increasing age, but it did not vary with calendar-year or registry area. Conclusions Our results indicate that early childhood exposures, male-sex, and White race may be risk factors for sporadic childhood BL in the United States. Keywords: epidemiology, pediatric cancer, non-Hodgkin lymphoma, HIV/AIDS

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Divergence dating studies, which combine temporal data from the fossil record with branch length data from molecular phylogenetic trees, represent a rapidly expanding approach to understanding the history of life. National Evolutionary Synthesis Center hosted the first Fossil Calibrations Working Group (3–6 March, 2011, Durham, NC, USA), bringing together palaeontologists, molecular evolutionists and bioinformatics experts to present perspectives from disciplines that generate, model and use fossil calibration data. Presentations and discussions focused on channels for interdisciplinary collaboration, best practices for justifying, reporting and using fossil calibrations and roadblocks to synthesis of palaeontological and molecular data. Bioinformatics solutions were proposed, with the primary objective being a new database for vetted fossil calibrations with linkages to existing resources, targeted for a 2012 launch.

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This paper presents an experimental investigation into the detection of excessive Diesel knock using acoustic emission signals. Three different dual-fuel Diesel engine operating regimes were induced into a compression ignition (Diesel) engine operating on both straight Diesel fuel and two different mixtures of fumigated ethanol and Diesel. The experimentally induced engine operating regimes were; normal, or Diesel only operation, acceptable dual-fuel operation and dual-fuel operation with excessive Diesel knock. During the excessive Diesel knock operating regime, high rates of ethanol substitution induced potentially damaging levels of Diesel knock. Acoustic emission data was captured along with cylinder pressure, crank-angle encoder, and top-dead centre signals for the different engine operating regimes. Using these signals, it was found that acoustic emission signals clearly distinguished between the two acceptable operating regimes and the operating regime experiencing excessive Diesel knock. It was also found that acoustic emission sensor position is critical. The acoustic emission sensor positioned on the block of the engine clearly related information concerning the level of Diesel knock occurring in the engine whist the sensor positioned on the head of the engine gave no indication concerning Diesel knock severity levels.

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This thesis develops a detailed conceptual design method and a system software architecture defined with a parametric and generative evolutionary design system to support an integrated interdisciplinary building design approach. The research recognises the need to shift design efforts toward the earliest phases of the design process to support crucial design decisions that have a substantial cost implication on the overall project budget. The overall motivation of the research is to improve the quality of designs produced at the author's employer, the General Directorate of Major Works (GDMW) of the Saudi Arabian Armed Forces. GDMW produces many buildings that have standard requirements, across a wide range of environmental and social circumstances. A rapid means of customising designs for local circumstances would have significant benefits. The research considers the use of evolutionary genetic algorithms in the design process and the ability to generate and assess a wider range of potential design solutions than a human could manage. This wider ranging assessment, during the early stages of the design process, means that the generated solutions will be more appropriate for the defined design problem. The research work proposes a design method and system that promotes a collaborative relationship between human creativity and the computer capability. The tectonic design approach is adopted as a process oriented design that values the process of design as much as the product. The aim is to connect the evolutionary systems to performance assessment applications, which are used as prioritised fitness functions. This will produce design solutions that respond to their environmental and function requirements. This integrated, interdisciplinary approach to design will produce solutions through a design process that considers and balances the requirements of all aspects of the design. Since this thesis covers a wide area of research material, 'methodological pluralism' approach was used, incorporating both prescriptive and descriptive research methods. Multiple models of research were combined and the overall research was undertaken following three main stages, conceptualisation, developmental and evaluation. The first two stages lay the foundations for the specification of the proposed system where key aspects of the system that have not previously been proven in the literature, were implemented to test the feasibility of the system. As a result of combining the existing knowledge in the area with the newlyverified key aspects of the proposed system, this research can form the base for a future software development project. The evaluation stage, which includes building the prototype system to test and evaluate the system performance based on the criteria defined in the earlier stage, is not within the scope this thesis. The research results in a conceptual design method and a proposed system software architecture. The proposed system is called the 'Hierarchical Evolutionary Algorithmic Design (HEAD) System'. The HEAD system has shown to be feasible through the initial illustrative paper-based simulation. The HEAD system consists of the two main components - 'Design Schema' and the 'Synthesis Algorithms'. The HEAD system reflects the major research contribution in the way it is conceptualised, while secondary contributions are achieved within the system components. The design schema provides constraints on the generation of designs, thus enabling the designer to create a wide range of potential designs that can then be analysed for desirable characteristics. The design schema supports the digital representation of the human creativity of designers into a dynamic design framework that can be encoded and then executed through the use of evolutionary genetic algorithms. The design schema incorporates 2D and 3D geometry and graph theory for space layout planning and building formation using the Lowest Common Design Denominator (LCDD) of a parameterised 2D module and a 3D structural module. This provides a bridge between the standard adjacency requirements and the evolutionary system. The use of graphs as an input to the evolutionary algorithm supports the introduction of constraints in a way that is not supported by standard evolutionary techniques. The process of design synthesis is guided as a higher level description of the building that supports geometrical constraints. The Synthesis Algorithms component analyses designs at four levels, 'Room', 'Layout', 'Building' and 'Optimisation'. At each level multiple fitness functions are embedded into the genetic algorithm to target the specific requirements of the relevant decomposed part of the design problem. Decomposing the design problem to allow for the design requirements of each level to be dealt with separately and then reassembling them in a bottom up approach reduces the generation of non-viable solutions through constraining the options available at the next higher level. The iterative approach, in exploring the range of design solutions through modification of the design schema as the understanding of the design problem improves, assists in identifying conflicts in the design requirements. Additionally, the hierarchical set-up allows the embedding of multiple fitness functions into the genetic algorithm, each relevant to a specific level. This supports an integrated multi-level, multi-disciplinary approach. The HEAD system promotes a collaborative relationship between human creativity and the computer capability. The design schema component, as the input to the procedural algorithms, enables the encoding of certain aspects of the designer's subjective creativity. By focusing on finding solutions for the relevant sub-problems at the appropriate levels of detail, the hierarchical nature of the system assist in the design decision-making process.

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The relationship between intellectual functioning and criminal offending has received considerable focus within the literature. While there remains debate regarding the existence (and strength) of this relationship, there is a wider consensus that individuals with below average functioning (in particular cognitive impairments) are disproportionately represented within the prison population. This paper focuses on research that has implications for the effective management of lower functioning individuals within correctional environments as well as the successful rehabilitation and release of such individuals back into the community. This includes a review of the literature regarding the link between lower intelligence and offending and the identification of possible factors that either facilitate (or confound) this relationship. The main themes to emerge from this review are that individuals with lower intellectual functioning continue to be disproportionately represented in custodial settings and that there is a need to increase the provision of specialised programs to cater for their needs. Further research is also needed into a range of areas including: (1) the reason for this over-representation in custodial settings, (2) the existence and effectiveness of rehabilitation and release programs that cater for lower IQ offenders, (3) the effectiveness of custodial alternatives for this group (e.g. intensive corrections orders) and (4) what post-custodial release services are needed to reduce the risk of recidivism.

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This publication consists of a volume of papers presented at the workshop of the CIB Task Group 58: Clients and Construction Innovation, held on May 18- 19, 2009 at the University of Alberta in Edmonton, Canada. The workshop theme, “Leveraging Innovation for Sustainable Construction”, reflects a growing concern among clients for perspectives, approaches, and tools that will secure the practice of construction economically, socially, and environmentally. This collection encompasses some of the most incisive assessments of the challenges facing the construction industry today from a range of researchers and industry practitioners who are leading the way for tomorrow’s innovations. It provides a useful documentation of the ongoing conversation regarding innovation and sustainability issues and a foundation of knowledge for future research and development. The papers contained in this volume explore the workshop’s overarching theme of how to leverage innovation to increase the sustainability of the construction process and product. Participants sought to generate discussion on the topics of innovation and sustainability within the construction field, to share international examples of innovation from the research community and from industry, and to establish a point of reference for ongoing enquiry. In particular, our contributors have noted the value of learning through practice in order to orient research based on real-world industry experience. Chapters two and three present complementary models of sustainable research programs through the three parts collaboration of government, industry, and academia. Chapters four and five explore new tools and forms of technological innovation as they are deployed to improve construction project management and set the direction for advances in research. Chapters six, seven, and eight closely study practical examples of innovation in large-scale construction projects, showing with concrete results the impact of applying creative methods and best practices to the field. Innovation and sustainability in construction are truly global efforts; these papers illustrate how we can draw on international examples and cooperative organizations to address these important issues for long-term benefit of the industry.

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This paper reports on an experiment that was conducted to determine the extent to which group dynamics impacts on the effectiveness of software development teams. The experiment was conducted on software engineering project students at the Queensland University of Technology (QUT).

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Several forms of elliptic curves are suggested for an efficient implementation of Elliptic Curve Cryptography. However, a complete description of the group law has not appeared in the literature for most popular forms. This paper presents group law in affine coordinates for three forms of elliptic curves. With the existence of the proposed affine group laws, stating the projective group law for each form becomes trivial. This work also describes an automated framework for studying elliptic curve group law, which is applied internally when preparing this work.

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The presence of air and bone interfaces makes the dose distribution for head and neck cancer treatments difficult to accurately predict. This study compared planning system dose calculations using the collapsed-cone convolution algorithm with EGSnrcMonte Carlo simulation results obtained using the Monte Carlo DICOMToolKit software, for one oropharynx, two paranasal sinus and three nodal treatment plans. The difference between median doses obtained from the treatment planning and Monte Carlo calculations was found to be greatest in two bilateral treatments: 4.8%for a retropharyngeal node irradiation and 6.7% for an ethmoid paranasal sinus treatment. These deviations in median dose were smaller for two unilateral treatments: 0.8% for an infraclavicular node irradiation and 2.8% for a cervical node treatment. Examination of isodose distributions indicated that the largest deviations between Monte Carlo simulation and collapsed-cone convolution calculations were seen in the bilateral treatments, where the increase in calculated dose beyond air cavities was most significant.

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Objective Factors associated with the development of hallux valgus (HV) are multifactorial and remain unclear. The objective of this systematic review and meta-analysis was to investigate characteristics of foot structure and footwear associated with HV. Design Electronic databases (Medline, Embase, and CINAHL) were searched to December 2010. Cross-sectional studies with a valid definition of HV and a non-HV comparison group were included. Two independent investigators quality rated all included papers. Effect sizes and 95% confidence intervals (CIs) were calculated (standardized mean differences (SMDs) for continuous data and risk ratios (RRs) for dichotomous data). Where studies were homogeneous, pooling of SMDs was conducted using random effects models. Results A total of 37 papers (34 unique studies) were quality rated. After exclusion of studies without reported measurement reliability for associated factors, data were extracted and analysed from 16 studies reporting results for 45 different factors. Significant factors included: greater first intermetatarsal angle (pooled SMD = 1.5, CI: 0.88–2.1), longer first metatarsal (pooled SMD = 1.0, CI: 0.48–1.6), round first metatarsal head (RR: 3.1–5.4), and lateral sesamoid displacement (RR: 5.1–5.5). Results for clinical factors (e.g., first ray mobility, pes planus, footwear) were less conclusive regarding their association with HV. Conclusions Although conclusions regarding causality cannot be made from cross-sectional studies, this systematic review highlights important factors to monitor in HV assessment and management. Further studies with rigorous methodology are warranted to investigate clinical factors associated with HV.

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The professional development needs of early career academics (ECAs) are increasingly subject to scrutiny. The literature notes writing groups can be successful in increasing research outputs and improving research track records – a core concern for ECAs. However, the pressure on ECAs to publish takes the pleasure out of writing for many. We argue writing groups, created by and for ECAs, can provide an environment for ECAs to (re)produce pleasure in writing and participation in the processes of academic review and debate. In addition, our experience of a writing group was that it provided a platform of social and emotional support contributing to our personal well-being and professional development.

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Parkinson’s disease (PD) is a progressive, chronic neurodegenerative disorder for which there is no known cure. Physical exercise programs may be used to assist with the physical management of PD. Several studies have demonstrated that community based physical therapy programs are effective in reducing physical aspects of disability among people with PD. While multidisciplinary therapy interventions may have the potential to reduce disability and improve the quality of life of people with PD, there is very limited clinical trial evidence to support or refute the use of a community based multidisciplinary or interdisciplinary programs for people with PD. A two group randomized trial is being undertaken within a community rehabilitation service in Brisbane, Australia. Community dwelling adults with a diagnosis of Idiopathic Parkinson’s disease are being recruited. Eligible participants are randomly allocated to a standard exercise rehabilitation group program or an intervention group which incorporates physical, cognitive and speech activities in a multi-tasking framework. Outcomes will be measured at 6-week intervals for a period of six months. Primary outcome measures are the Montreal Cognitive Assessment (MoCA) and the Timed Up and Go (TUG) cognitive test. Secondary outcomes include changes in health related quality of life, communication, social participation, mobility, strength and balance, and carer burden measures. This study will determine the immediate and long-term effectiveness of a unique multifocal, interdisciplinary, dual-tasking approach to the management of PD as compared to an exercise only program. We anticipate that the results of this study will have implications for the development of cost effective evidence based best practice for the treatment of people with PD living in the community.