844 resultados para Data mining and knowledge discovery
Resumo:
The Last Interglacial (LIG), corresponding to Marine Isotope Stage (MIS) 5e, provides a reference of interglacial climate variability in the absence of anthropogenic forcing. Using an expanded section of the LIG gained at Integrated Ocean Drilling Program Site U1304 in the Subarctic Atlantic, we demonstrate that the early MIS 5e was marked by oceanographic conditions conducive for high diatom production and accumulation. The appearance of diatom-dominated laminated oozes ~3 k.y. after the beginning of MIS 5e at ca. 125 ka coincides with a shift to higher d30Sidiat values together with the dominance of Thalassiothrix longissima, indicative of increased nutrient availability and silicic acid utilization in surface waters. Though the Subarctic Front provided the physical conditions for high diatom production and deposition, these processes alone are insufficient to explain the high rates of siliceous productivity and the formation of diatomaceous sediments. Instead, the additional presence of an increased nutrient pool provided by Subantarctic Mode Water played the decisive role in initiating and sustaining diatom production. The high diatom productivity and the occurrence of diatomaceous sediments in the late Quaternary challenge the current hypothesis of a silica-depleted North Atlantic during the LIG.
Resumo:
Objective
To explore the concerns, needs and knowledge of women diagnosed with Gestational Diabetes Mellitus (GDM).
Design
A qualitative study of women with GDM or a history of GDM.
Methods
Nineteen women who were both pregnant and recently diagnosed with GDM or post- natal with a recent history of GDM were recruited from outpatient diabetes care clinics. This qualitative study utilised focus groups. Participants were asked a series of open-ended questions to explore 1) current knowledge of GDM; 2) anxiety when diagnosed with GDM, and whether this changed overtime; 3) understanding and managing GDM and 4) the future impact of GDM. The data were analysed using a conventional content analysis approach.
Findings
Women experience a steep learning curve when initially diagnosed and eventually become skilled at managing their disease effectively. The use of insulin is associated with fear and guilt. Diet advice was sometimes complex and not culturally appropriate. Women appear not to be fully aware of the short or long-term consequences of a diagnosis of GDM.
Conclusions
Midwives and other Health Care Professionals need to be cognisant of the impact of a diagnosis of GDM and give individual and culturally appropriate advice (especially with regards to diet). High quality, evidence based information resources need to be made available to this group of women. Future health risks and lifestyle changes need to be discussed at diagnosis to ensure women have the opportunity to improve their health.
Resumo:
Targeted cancer therapy aims to disrupt aberrant cellular signalling pathways. Biomarkers are surrogates of pathway state, but there is limited success in translating candidate biomarkers to clinical practice due to the intrinsic complexity of pathway networks. Systems biology approaches afford better understanding of complex, dynamical interactions in signalling pathways targeted by anticancer drugs. However, adoption of dynamical modelling by clinicians and biologists is impeded by model inaccessibility. Drawing on computer games technology, we present a novel visualisation toolkit, SiViT, that converts systems biology models of cancer cell signalling into interactive simulations that can be used without specialist computational expertise. SiViT allows clinicians and biologists to directly introduce for example loss of function mutations and specific inhibitors. SiViT animates the effects of these introductions on pathway dynamics, suggesting further experiments and assessing candidate biomarker effectiveness. In a systems biology model of Her2 signalling we experimentally validated predictions using SiViT, revealing the dynamics of biomarkers of drug resistance and highlighting the role of pathway crosstalk. No model is ever complete: the iteration of real data and simulation facilitates continued evolution of more accurate, useful models. SiViT will make accessible libraries of models to support preclinical research, combinatorial strategy design and biomarker discovery.
Resumo:
Responsible Research Data Management (RDM) is a pillar of quality research. In practice good RDM requires the support of a well-functioning Research Data Infrastructure (RDI). One of the challenges the research community is facing is how to fund the management of research data and the required infrastructure. Knowledge Exchange and Science Europe have both defined activities to explore how RDM/RDI are, or can be, funded. Independently they each planned to survey users and providers of data services and on becoming aware of the similar objectives and approaches, the Science Europe Working Group on Research Data and the Knowledge Exchange Research Data expert group joined forces and devised a joint activity to to inform the discussion on the funding of RDM/RDI in Europe.
Resumo:
The purpose of this study was to identify the structural pathways of personal cognition and social context as they influence knowledge sharing behaviors in communities of practice. Based on the existing literature, ten hypotheses and a conceptual model built on the basis of the social cognitive theory were developed regarding the interrelationships of the five constructs: self-efficacy for knowledge sharing, outcome expectations, sense of community, leadership of a community, and knowledge sharing. The data were collected through an online questionnaire from the employees who have participated in communities of practice in a Fortune 100 corporation. A total of 438 usable questionnaires were collected. Overall, three analyses were conducted in order to prove the given hypotheses: (a) hypothesized measurement model fit, (b) relational and influential associations among the constructs, and (c) structural equation model analysis (SEM). In addition, open-ended responses were analyzed. The results presented that (a) hypothesized measurement models were valid and reliable, (b) personal cognitive factors, self-efficacy and outcome expectations for knowledge sharing, were found to be significant predictors of community members’ sense of community and knowledge sharing behaviors, (c) sense of community had the most significant impact on the knowledge sharing, (d) as the perceived social context, sense of community mediated the effects of personal cognition on knowledge sharing behaviors, and (e) personal cognition and social context jointly contributed to knowledge sharing. In brief, all of the hypotheses were positively supported. A conclusive summary is provided along with contributive discussion. Implications and contributions to HRD researchers and practitioners are discussed, and recommendations are provided.
Resumo:
This paper presents a new hyper-heuristic method using Case-Based Reasoning (CBR) for solving course timetabling problems. The term Hyper-heuristics has recently been employed to refer to 'heuristics that choose heuristics' rather than heuristics that operate directly on given problems. One of the overriding motivations of hyper-heuristic methods is the attempt to develop techniques that can operate with greater generality than is currently possible. The basic idea behind this is that we maintain a case base of information about the most successful heuristics for a range of previous timetabling problems to predict the best heuristic for the new problem in hand using the previous knowledge. Knowledge discovery techniques are used to carry out the training on the CBR system to improve the system performance on the prediction. Initial results presented in this paper are good and we conclude by discussing the con-siderable promise for future work in this area.
Resumo:
This study examines the organizational structures and decision-making processes used by school districts to recruit and hire school librarians. For students to acquire the information and technology literacy education they need, school libraries must be staffed with qualified individuals who can fulfill the librarian’s role as leader, teacher, instructional partner, information specialist, and program administrator. Principals are typically given decision rights for hiring staff, including school librarians. Research shows that principals have limited knowledge of the skills and abilities of the school librarian or the specific needs and functions of the library program. Research also indicates that those with specific knowledge of school library programs, namely school district library supervisors, are only consulted on recruiting and hiring about half the time. School districts entrust library supervisors with responsibilities such as professional development of school librarians only after they are hired. This study uses a theoretical lens from research on IT governance, which focuses on the use of knowledge-fit in applying decision rights in an organization. This framework is appropriate because of its incorporation of a specialist with a specific knowledge set in determining the placement of input and decision rights in the decision-making processes. The method used in this research was a multiple-case study design using five school districts as cases, varying by the involvement of the supervisors and other individuals in the hiring process. The data collected from each school district were interviews about the district’s recruiting and hiring practices with principals, an individual in HR, library supervisors, and recently hired school librarians. Data analysis was conducted through iterative coding from themes in the research questions, with continuous adjustments as new themes developed. Results from the study indicate that governance framework is applicable to evaluating the decision-making processes used in recruiting and hiring school librarians. However, a district’s use of governance did not consistently use knowledge-fit in the determination of input and decision rights. In the hiring process, governance was more likely to be based on placing decision rights at a certain level of the district hierarchy rather than the location of specific knowledge, most often resulting in site-based governance for decision rights at the school-building level. The governance of the recruiting process was most affected by the shortage or surplus of candidates available to the district to fill positions. Districts struggling with a shortage of candidates typically placed governance for the decision-making process on recruiting at the district level, giving the library supervisor more opportunity for input and collaboration with human resources. In districts that use site-based governance and that place all input and decision rights at the building level, some principals use their autonomy to eliminate the school library position in the allotment phase or hire librarians that, while certified through testing, do not have the same level of expertise as those who achieve certification through LIS programs. The principals in districts who use site-based governance for decision rights but call on the library supervisor for advisement stated how valuable they found the supervisor’s expertise in evaluating candidates for hire. In no district was a principal or school required to involve the library supervisor in the hiring of school librarians. With a better understanding of the tasks involved, the effect of district governance on decision-making, and the use of knowledge to assign input and decision rights, it is possible to look at how all of these factors affect the outcome in the quality of the hire. A next step is to look at the hiring process that school librarians went through and connect those with the measurable outcomes of hiring: school librarian success, retention, and attrition; the quality of school library program services, outreach, and involvement in a school; and the perceptions of the success of the school librarian and the library program as seen from students, teachers, administrators, parents, and other community stakeholders.