891 resultados para Network deployment methods
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Wireless mesh networks present an attractive communication solution for various research and industrial projects. However, in many cases, the appropriate preliminary calculations which allow predicting the network behavior have to be made before the actual deployment. For such purposes, network simulation environments emulating the real network operation are often used. Within this paper, a behavior comparison of real wireless mesh network (based on 802.11s amendment) and the simulated one has been performed. The main objective of this work is to measure performance parameters of a real 802.11s wireless mesh network (average UDP throughput and average one-way delay) and compare the derived results with characteristics of a simulated wireless mesh network created with the NS-3 network simulation tool. Then, the results from both networks are compared and the corresponding conclusion is made. The corresponding results were derived from simulation model and real-worldtest-bed, showing that the behavior of both networks is similar. It confirms that the NS-3 simulation model is accurate and can be used in further research studies.
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Background and Aims The males and females of many dioecious plant species differ from one another in important life-history traits, such as their size. If male and female reproductive functions draw on different resources, for example, one should expect males and females to display different allocation strategies as they grow. Importantly, these strategies may differ not only between the two sexes, but also between plants of different age and therefore size. Results are presented from an experiment that asks whether males and females of Mercurialis annua, an annual plant with indeterminate growth, differ over time in their allocation of two potentially limiting resources (carbon and nitrogen) to vegetative (below-and above-ground) and reproductive tissues.Methods Comparisons were made of the temporal patterns of biomass allocation to shoots, roots and reproduction and the nitrogen content in the leaves between the sexes of M. annua by harvesting plants of each sex after growth over different periods of time.Key Results and Conclusions Males and females differed in their temporal patterns of allocation. Males allocated more to reproduction than females at early stages, but this trend was reversed at later stages. Importantly, males allocated proportionally more of their biomass towards roots at later stages, but the roots of females were larger in absolute terms. The study points to the important role played by both the timing of resource deployment and the relative versus absolute sizes of the sinks and sources in sexual dimorphism of an annual plant.
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Functional connectivity in human brain can be represented as a network using electroencephalography (EEG) signals. These networks--whose nodes can vary from tens to hundreds--are characterized by neurobiologically meaningful graph theory metrics. This study investigates the degree to which various graph metrics depend upon the network size. To this end, EEGs from 32 normal subjects were recorded and functional networks of three different sizes were extracted. A state-space based method was used to calculate cross-correlation matrices between different brain regions. These correlation matrices were used to construct binary adjacency connectomes, which were assessed with regards to a number of graph metrics such as clustering coefficient, modularity, efficiency, economic efficiency, and assortativity. We showed that the estimates of these metrics significantly differ depending on the network size. Larger networks had higher efficiency, higher assortativity and lower modularity compared to those with smaller size and the same density. These findings indicate that the network size should be considered in any comparison of networks across studies.
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PURPOSE: To better define outcome and prognostic factors in primary pineal tumors. MATERIALS AND METHODS: Thirty-five consecutive patients from seven academic centers of the Rare Cancer Network diagnosed between 1988 and 2006 were included. Median age was 36 years. Surgical resection consisted of biopsy in 12 cases and resection in 21 (2 cases with unknown resection). All patients underwent radiotherapy and 12 patients received also chemotherapy. RESULTS: Histological subtypes were pineoblastoma (PNB) in 21 patients, pineocytoma (PC) in 8 patients and pineocytoma with intermediate differentiation in 6 patients. Six patients with PNB had evidence of spinal seeding. Fifteen patients relapsed (14 PNB and 1 PC) with PNB cases at higher risk (p = 0.031). Median survival time was not reached. Median disease-free survival was 82 months (CI 50 % 28-275). In univariate analysis, age younger than 36 years was an unfavorable prognostic factor (p = 0.003). Patients with metastases at diagnosis had poorer survival (p = 0.048). Late side effects related to radiotherapy were dementia, leukoencephalopathy or memory loss in seven cases, occipital ischemia in one, and grade 3 seizures in two cases. Side effects related to chemotherapy were grade 3-4 leucopenia in five cases, grade 4 thrombocytopenia in three cases, grade 2 anemia in two cases, grade 4 pancytopenia in one case, grade 4 vomiting in one case and renal failure in one case. CONCLUSIONS: Age and dissemination at diagnosis influenced survival in our series. The prevalence of chronic toxicity suggests that new adjuvant strategies are advisable.
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El treball realitzat en aquest projecte es basa en l'implementació d'un demostrador wireless, i més específicament, en l'estudi de les tècniques network coding i virtualització. Network coding és un nou mètode de transmissió de dades que es basa en la codificació de paquets per incrementar el rendiment fins ara obtingut als mètodes de transmissió convencionals. La virtualització és una tècnica que consisteix en compartir de forma més eficient els recursos d'un sistema. En el nostre cas s'utilitzarà la virtualització per dividir una interfície sense fils en diferents usuaris virtuals transmetent i rebent dades simultàniament. L'objectiu del projecte és realitzar un seguit de proves i estudis per veure els avantatges d'aquestes dues tècniques.
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Aim: The study aims to describe the activities of the Swiss Early Psychosis Project (SWEPP) which was founded in 1999 as a national network to further and disseminate knowledge on early psychosis (EP) and to enhance collaboration between healthcare groups. Methods: The present paper is a detailed account of the initiation and the development of the Swiss network. We describe all activities such as the several educational campaigns that were addressed to primary and secondary care groups since the early days. We also provide an overview of the current status of EP services throughout the country. Results: Today, most regions in Switzerland provide specialized EP inpatient and/or outpatient services with a clinical or combined clinical research approach that targets at-risk and/or first-episode populations. Some more recently initiated EP services have been launched as collaborative models between several local or regional psychiatric services. Conclusions: The increasing number of EP services and experts in Switzerland may mirror the catalyzing contribution of the Swiss Early Psychosis Project in this important field of health care. The country's small size and the increasing density of specialized services provide excellent bases for larger-scale networking activities in the future, both in clinical and research areas.
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Specific properties emerge from the structure of large networks, such as that of worldwide air traffic, including a highly hierarchical node structure and multi-level small world sub-groups that strongly influence future dynamics. We have developed clustering methods to understand the form of these structures, to identify structural properties, and to evaluate the effects of these properties. Graph clustering methods are often constructed from different components: a metric, a clustering index, and a modularity measure to assess the quality of a clustering method. To understand the impact of each of these components on the clustering method, we explore and compare different combinations. These different combinations are used to compare multilevel clustering methods to delineate the effects of geographical distance, hubs, network densities, and bridges on worldwide air passenger traffic. The ultimate goal of this methodological research is to demonstrate evidence of combined effects in the development of an air traffic network. In fact, the network can be divided into different levels of âeurooecohesionâeuro, which can be qualified and measured by comparative studies (Newman, 2002; Guimera et al., 2005; Sales-Pardo et al., 2007).
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Background Cruciferous vegetables have been suggested to protect against various cancers, though the issue is open to discussion. To further understand their role, we analyzed data from a network of case-control studies conducted in Italy and Switzerland. Patients and methods The studies included a total of 1468 cancers of the oral cavity/pharynx, 505 of the esophagus, 230 of the stomach, 2390 of the colorectum, 185 of the liver, 326 of the pancreas, 852 of the larynx, 3034 of the breast, 367 of the endometrium, 1031 of the ovary, 1294 of the prostate, 767 of the kidney, and 11 492 controls. All cancers were incident, histologically confirmed; controls were subjects admitted to the same network of hospitals as cases for a wide spectrum of acute nonneoplastic conditions. Results The multivariate odds ratio (OR) for consumption of cruciferous vegetables at least once a week as compared with no/occasional consumption was significantly reduced for cancer of the oral cavity/pharynx (OR = 0.83), esophagus (OR = 0.72), colorectum (OR = 0.83), breast (OR = 0.83), and kidney (OR = 0.68). The OR was below unity, but not significant, for stomach (OR = 0.90), liver (OR = 0.72), pancreatic (OR = 0.90), laryngeal (OR = 0.84), endometrial (OR = 0.93), ovarian (OR = 0.91), and prostate (OR = 0.87) cancer. Conclusion This large series of studies provides additional evidence of a favorable effect of cruciferous vegetables on several common cancers.
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PURPOSE OF REVIEW: Invasive candidiasis is a severe infectious complication occurring mostly in onco-hematologic and surgical patients. Its conventional diagnosis is insensitive and often late, leading to a delayed treatment and a high mortality. The purpose of this article is to review recent contributions in the nonconventional diagnostic approaches of invasive candidiasis, both for the detection of the epidose and the characterization of the etiologic agent. RECENT FINDINGS: Antigen-based tests to detect invasive candidiasis comprise a specific test, mannan, as well as a nonspecific test, beta-D-glucan. Both have a moderate sensitivity and a high specificity, and cannot be recommended alone as a negative screening tool or a positive syndrome driven diagnostic tool. Molecular-based tests still have not reached the stage of rapid, easy to use, standardized tests ideally complementing blood culture at the time of blood sampling. New tests (fluorescence in-situ hybridization or mass spectrometry) significantly reduce the delay of identification of Candida at the species level in positive blood cultures, and should have a positive impact on earlier appropriate antifungal therapy and possibly on outcome. SUMMARY: Both antigen-based and molecular tests appear as promising new tools to complement and accelerate the conventional diagnosis of invasive candidiasis with an expected significant impact on earlier and more focused treatment and on prognosis.
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NICaN Regional Supportive & Palliative Care Network Friday 30th May 2008 Lecture Theatre, Fern House Antrim 2.00 pm - 5.00 pm Welcome, Introductions Stuart MacDonnell, Chair of the Supportive and Palliative Care network welcomed everyone to the meeting. This meeting had been rescheduled to accommodate the validation workshop for the regional palliative care model, which took place on Friday,18th April. Acknowledging the full agenda, several items were pulled forward to accommodate speakers SPC_0809_03 Modernisation and Reform of Supportive and Palliative care Mr MacDonnell welcomed Dr Sonja McIlfatrick and Dr Donna Fitzimons, members of the Phase 1 Project Team for the Modernisation and Reform of palliative care. Their presentation highlighted the journey taken by the Project Team since January 2008 - May 2008. Seeking to deliver the network vision, for any person with palliative care need, cancer or non - cancer, the project team incorporated several methodologies. The literature review identified best practice. An assessment of need including epidemiological data and review of service provision. Consultation reflected the engagement with patients, carers and professional forums, primary care and non-malignant focus groups. The breadth of consultation confirmed the evidence for the identified components of the model. These were validated at the April workshop. External review of the work was provided by Dr Phil Larkin (Galway Uni) Prof David Clark (End of Life Care Observatory, Lancaster University) and Mr Bob Neillans (Chair of the Mid Trent Palliative care network, which has been involved in the Delivering choice programme within Lincolnshire). The Guiding Principles of the model reinforced Patient and family centred care, enhanced community provision and supported by specialists. The components of the model are · Identification of patient with Palliative careened · Holistic Assessment · Integration of services · Coordination of care · End of Life Care and Bereavement Care The consultation process also highlighted the need for Increased Public and Professional Awareness. This was recognised as an encompassing component. Underpinning the model is the need for robust Education and common core values e.g. dignity, choice, advocacy, empowerment, partnership working. Stuart MacDonnell, who also chaired the steering group during the project, congratulated the Project Team for delivering the comprehensive document on schedule. The Report has been submitted to the NICaN Board and the DHSSPSNI. In addition, an outline for Phase 2 of this work has been submitted. Mr MacDonnell recognised that there is real opportunity for palliative care to benefit from the DHSSPSNI commitment to concrete developments. Phase 2 will progress the current high-level components of the model into quality services developments at a local level, demonstrating integration throughout. The methods propose continued engagement with the Delivering Choice Programme enabled through a Central and also Local Teams. The report and the Appendices care available on the NICaN website www.nican@n-i.nhs.uk SPC_0809_01 Chairman's Business · Update on the Cancer Service Framework, the document has been submitted and presented to the Departmental Programme Board. Next stages will include the review of costs and development of a implementation guidance It is hoped that the completed document should be available for public consultation in Autumn 2008. with a launch of the framework document and accompanying implementation guide in Spring 2009. Some funding has already been identified to advance key areas of work including, Advanced communication skills training, peer review and an appointment of a post to develop the cancerni.net, focusing on children and e-learning tools. · Children's and Adolescent Cancer network group , Liz Henderson is to convene a group to consider how this is to be taken forward. · NICaN appointments Recognition was given to the significant contribution made by Dr Gerard Daly during his position as NICaN Lead Clinician, particularly throughout the early establishment of the NICaN. Dr Dermott Hughes (Western Trust) has been appointed as the NICaN Medical Director. The Primary Care Director post has been advertised and it is hoped that the Director of Network will be advertised later in Summer. Endorsement of End of Life care paper. The Paper was presented and endorsed at the March 2008 NICaN Board meeting. Mr David Galloway (Director of Secondary Care) emphasised the need for this important work to be recognised within the regional model to ensure that it is reflected in future models of service delivery Congratulations were again echoed to the Chair of the End of Life Group for this work, Dr Glynis Henry, and the working group Other recognition Mr MacDonnell congratulated the significant achievements across the network. These include: · Dr Francis Robinson (Consultant Palliative Medicine, Western Trust) Awarded - Consultant of the year at the NI Health Care awards. · Mrs Evelyn Whittaker Hospice Nurse Specialist, NI Hospice, Joint Second Prize in the Development award within the International Journal of Palliative Nursing Awards, for her work in development of palliative care education in nursing homes. · Mr Ray Elder is the newly appointed Team Leader of Community Palliative care, SE Trust. · Mrs Bridget Denvir, who managed the establishment of one of the first community multiprofessional palliative care teams is moving to work with establishing integrated teams within the Belfast Trust. Bridget has been an active core member of the network and here contribution has been much appreciated. Mrs Sharon Barr will attend in future. SPC_0809_02 Minutes & matters Arising from Meeting, 13th December 2007 No amendments were made to the draft minutes from the December meeting. These will be posted on the NICaN website for future reference. Palliative Care Research Following consultation, the response to the business case for the All Ireland Institute was forwarded on 22 February 2008 to Prof David Clark. Prof Judith Hill informed the group that terms of tender are now being developed. Awareness raising across academic institutions continues to engage interest in potential partnerships. Atlantic Philantrophies have offered financial support to the venture and match funding is being sought from across jurisdictions. Previous discussions at Network meetings have endorsed the need to establish a work strand for research and development within palliative and end of life care. To identify the body of interested parties and explore the strengths and weaknesses of a collaborative model for research, a workshop, - Building collaboration for Palliative and End of life Care Research -will take place on 4 June 10am - 2pm.in the Comfort Hotel.Antrim, The workshop will be chaired by Prof David Clark, Director of the International Observatory on End of Life Care. Prof Shelia Payne, Help the Hospices Chair in Hospice Studies and co director of the Cancer Experiences Collaborative will present the Experiences and Results from Research Collaborative. Feedback from this event will be brought back to the next meeting in September. SPC_0809_04 Patient Information pathways - a pathway for advanced disease Ms Danny Sinclair, NICaN Regional Coordinator for Patient Information informed the network of how patient information pathways have been developed in line with the Cancer Services Collaborative. Emerging themes, with regard to information needs of patients with advanced disease, are being identified from the work undertaken across the tumour groups. It is important to identify all information needs to develop a generic pathway of information resources for advanced disease to be endorsed by the Supportive and Palliative care network. This could be used across the all tumour specific information pathways and across organisational boundaries. The resulting pathway could potentially be used for non- cancer condition. A group is to be established to take this work forward. The group will: · Develop a list of advanced disease information themes · .Identify when they become relevant for the patient or their carer · .Identify existing resources · .Develop resources where needed · .Participate or nominate when review is required Dr Sheila Kelly nominated Helen Hume (SETrust) Paula Kealey will also contribute to this work; a nomination from the Patient and Public Information Forum has also been identified. A date will be circulated across the network to engage further interest and establish group SPC_0809_08 Development of a Regional Syringe Driver Prescription Chart Ms Kathy Stephenson reported that the second consultation of the draft regional syringe driver prescription chart and the focus group discussions, Pilots of the chart are to be undertaken within Trust, Hospices and General Practices. SPC_0809_05 A framework for Generalist and Specialist Palliative and End of Life Care Competency Dr Kathleen Dunne, lead of the Education works strand, reported on the findings following consultation of the Education framework. The report was widely appreciated across the network and valued as a significant and timely document for the commissioning of generalist and specialist adult palliative care education. Mr MacDonnell congratulated Dr Dunne and the members of the education workstrand for developing the framework aligning its significance to the underpinning needs of the regional model Amendments will be made to the document and then forwarded to the NICaN Board for endorsement. A process of implementation will be explored and reported to the network group at the September meeting. Key target areas for generalist palliative care education were highlighted within care of the elderly and general medicine. . SPC_0809_06 Pallcareni.net-a website for people with palliative care needs Ms Danny Sinclair, reminded the group of the pending amalgamation of the CAPriCORN and NICaN website. The resulting new web address will be www. cancerni.net. Recurrent funding has been secured to ensure the development of the supportive and palliative care website.www.Pallcareni.net The new website will host good information for people with palliative care needs, regardless of diagnosis. It will be accessible via the cancerni.net portal or independently as the pallcareni portal. It will signpost people with palliative care needs to condition- specific websites. The website will also enable the communication needs of the NI Regional Supportive & Palliative Care Network. This is a very significant method of seeking to enable greater understanding of palliative care for public and professionals, as highlighted within the regional model. Currently the material from the CAPriCORN website is being migrated onto cancerni and /or pallcareni.net as appropriate. To enable the further development of this opportunity a steering group of interested individuals is to be established. Their role will be to: · Drive the development of the website so it meets the needs of public and professionals through the sourcing and development of additional content · Identify any support that is needed, e.g. technical support · Review the website as a whole as it grows (coordinating condition-specific developments) · Review the functions of the website to aid communication throughout the Supportive and Palliative care network The steering group representation should reflect the constituencies within the Supportive and Palliative Care network. Current expressions of interest have come from Heather Reid and Valerie Peacock. A date will be circulated across the network to engage further interest and establish group SPC_0809_07 Update of Guidelines workstrand Dr Pauline Wilkinson presented the current work within the guidelines workstrand. 1. Brief Holistic Assessment & Referral Criteria to Specialist Palliative Care The development of an Holistic assessment Tool will help to identify holistic need at generalist and specialist level. Recognition of complex need prompts appropriate referral to specialist palliative care. The regional referral form is compatible with the Minimum Data set. The final drafts of this work are to be circulated widely, inclusive of service framework groups, primary care, secondary care and the supportive and palliative care network. Consultation will take place during June and July. Piloting of the forms will also be undertaken. 2. Control of Pain in Cancer Patients The original guidelines where developed 2003 and are now ready for review. The Mapping exercise, undertaken in May 2007, highlighted that the Guidelines were poorly adopted. The group have reviewed the pending SIGN 2 guidelines for pain with regard to practice in Northern Ireland. These are highly evidence based and are due to be launched this Summer. Whilst an excellent resource their comprehensiveness limits their readability, this may result in poor compliance. The Guidelines group feel it is important to have accessible and user-friendly guidelines particularly for Generalists and Out of hours. There are examples of good work that has taken place across the province, but there is a need for regional consistency. Dr Wilkinson has contacted Dr Carolyn Harper (Deputy CMO) and GAIN with regard to enabling funding to progress this work. The Guidelines group hope to approach the NICaN Primary Care Group to work in collaboratively on this piece, based on the templates already available. The works should be available in both electronic and paper versions. 3. Care of the dying & Breaking bad news Dr Gail Johnston has now completed an Audit of the Care of the Dying Pathways within the EHSSB. Gail is also seeking to examine to what extent the Regional Guidelines for Breaking Bad News are being implemented in the EHSSB with a view to identifying the need for further training or organisational structures that would facilitate future uptake. 4. Advances in new Technology Syringe Drivers Dr Wilkinson reported on a presentation made to the guidelines group by Mr Jim Elliot, Principle Engineer, Cardiology & Ann McLean, and Macmillan Palliative Care Nurse RVH. There is increasing concern with regard to how devices meet the recommended safety standards and how to reduce error. New devices have 3 point checking, automatic detection of syringe, automatic flow rates, full range of alarms, battery status and data download to provide an event log. There are now 2 companies in UK who have devices that meet these safety criteria. The current Graseby syringe drivers, which have been on the market and used predominately within Northern Ireland over the past 27 years Most new devices are not compatible with the regionally available monoject syringe, however contractual changes will lead to the withdrawal of the monoject syringes in October 2008. The Guidelines group supports a regional approach to this matter. This was echoed in the Supportive and Palliative care network. An option appraisal, identifying costs, and training issues should be developed through the engagement with Trusts and DHSSPSNI. The issue of Patient safety should be raised with the DHSSPSNI. SPC_0809_09 Evaluation of Supportive and Palliative Care network Deferred to next meeting. . SPC_0809_10 Emerging Issues Mrs Anne Coyle, Bereavement Coordinator, Southern Trust, announced that the Regional Bereavement Strategy is soon to be released. Anne supported the close alignment between the content of the strategy and the work of the regional model and other workstrands within the Supportive and Palliative care network. Ms Eleanor Donaghy, Transplant Coordinator, briefly highlighted the issue of tissue donation. Each year Northern Ireland has a dearth of corneal donations. There is no upper age limit for donation and retrieval is not limited by a cancer diagnosis. Recipients do not require immunosuppressive and the transplant is lifelong. The National Blood Service provided coordination of this donation they may be contacted via 07659180773. It is hoped that Mrs Coyle and Ms Donaghy could provide more comprehensive presentations at a future meeting. Events · Irish Psycho- Oncology Group Seminar, Cork 6 June, Exploring the Struggle for meaning in Cancer · Integrated Care: Putting Research into Practice, 13June, Trinity College, Dublin · Macmillan online conference Friday 13 June 2008, 9am - 5pm · Delivering effective end of life care: developing partnership working 15 Oct 2008, 9.30 -4.15 pm London Network Meeting was closed at 5.00pm SPC_0607_ Dates of Future Meetings (please note the change of venue) 10th September 2008, 1.30 - 5pm venue to be decided15th January 2009, 1.30 - 5pm venue to be decided12th May 2009, 1.30 - 5pm venue to be decided Attendances Apologies Stuart MacDonnellLorna NevinSonja McIlfatrick Donna FitzsimonsKathleen DunnePauline WilkinsonKathy StephensonSheila KellyMarie Nugent,Anne CoyleFiona GilmourJudith HillLorna DicksonMargaret CarlinLoretta GribbenYvonne Duff Lesley NelsonLiz HendersonSue FosterCathy PayneGraeme PaynePatricia MageeGeraldine WeatherupPaula KealyCaroline McAfeeLinda WrayValerie PeacockAnn McCleanRay Elder Martin BradleyHelen HumeGillian RankinHeather MonteverdeJulie DoyleAlison PorterYvonne SmythLiz Atkinson,Glynis HenryMaeve HullyCaroline HughesAnn FinnBob BrownSharon BarrJulie DoyleJanis McCulla .
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In occupational exposure assessment of airborne contaminants, exposure levels can either be estimated through repeated measurements of the pollutant concentration in air, expert judgment or through exposure models that use information on the conditions of exposure as input. In this report, we propose an empirical hierarchical Bayesian model to unify these approaches. Prior to any measurement, the hygienist conducts an assessment to generate prior distributions of exposure determinants. Monte-Carlo samples from these distributions feed two level-2 models: a physical, two-compartment model, and a non-parametric, neural network model trained with existing exposure data. The outputs of these two models are weighted according to the expert's assessment of their relevance to yield predictive distributions of the long-term geometric mean and geometric standard deviation of the worker's exposure profile (level-1 model). Bayesian inferences are then drawn iteratively from subsequent measurements of worker exposure. Any traditional decision strategy based on a comparison with occupational exposure limits (e.g. mean exposure, exceedance strategies) can then be applied. Data on 82 workers exposed to 18 contaminants in 14 companies were used to validate the model with cross-validation techniques. A user-friendly program running the model is available upon request.
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This article uses a mixed methods design to investigate the effects of social influence on family formation in a sample of eastern and western German young adults at an early stage of their family formation. Theoretical propositions on the importance of informal interaction for fertility and family behavior are still rarely supported by systematic empirical evidence. Major problems are the correct identification of salient relationships and the comparability of social networks across population subgroups. This article addresses the two issues through a combination of qualitative and quantitative data collection and analysis. In-depth interviewing, network charts, and network grids are used to map individual personal relationships and their influence on family formation decisions. In addition, an analysis of friendship dyads is provided.
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Genetically engineered bioreporters are an excellent complement to traditional methods of chemical analysis. The application of fluorescence flow cytometry to detection of bioreporter response enables rapid and efficient characterization of bacterial bioreporter population response on a single-cell basis. In the present study, intrapopulation response variability was used to obtain higher analytical sensitivity and precision. We have analyzed flow cytometric data for an arsenic-sensitive bacterial bioreporter using an artificial neural network-based adaptive clustering approach (a single-layer perceptron model). Results for this approach are far superior to other methods that we have applied to this fluorescent bioreporter (e.g., the arsenic detection limit is 0.01 microM, substantially lower than for other detection methods/algorithms). The approach is highly efficient computationally and can be implemented on a real-time basis, thus having potential for future development of high-throughput screening applications.
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Background The 'database search problem', that is, the strengthening of a case - in terms of probative value - against an individual who is found as a result of a database search, has been approached during the last two decades with substantial mathematical analyses, accompanied by lively debate and centrally opposing conclusions. This represents a challenging obstacle in teaching but also hinders a balanced and coherent discussion of the topic within the wider scientific and legal community. This paper revisits and tracks the associated mathematical analyses in terms of Bayesian networks. Their derivation and discussion for capturing probabilistic arguments that explain the database search problem are outlined in detail. The resulting Bayesian networks offer a distinct view on the main debated issues, along with further clarity. Methods As a general framework for representing and analyzing formal arguments in probabilistic reasoning about uncertain target propositions (that is, whether or not a given individual is the source of a crime stain), this paper relies on graphical probability models, in particular, Bayesian networks. This graphical probability modeling approach is used to capture, within a single model, a series of key variables, such as the number of individuals in a database, the size of the population of potential crime stain sources, and the rarity of the corresponding analytical characteristics in a relevant population. Results This paper demonstrates the feasibility of deriving Bayesian network structures for analyzing, representing, and tracking the database search problem. The output of the proposed models can be shown to agree with existing but exclusively formulaic approaches. Conclusions The proposed Bayesian networks allow one to capture and analyze the currently most well-supported but reputedly counter-intuitive and difficult solution to the database search problem in a way that goes beyond the traditional, purely formulaic expressions. The method's graphical environment, along with its computational and probabilistic architectures, represents a rich package that offers analysts and discussants with additional modes of interaction, concise representation, and coherent communication.
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OBJECTIVES: To assess the effectiveness of implementing guidelines, coupled with individual feedback, on antibiotic prescribing behaviour of primary care physicians in Switzerland. METHODS: One hundred and forty general practices from a representative Swiss sentinel network of primary care physicians participated in this cluster-randomized prospective intervention study. The intervention consisted of providing guidelines on treatment of respiratory tract infections (RTIs) and uncomplicated lower urinary tract infections (UTIs), coupled with sustained, regular feedback on individual antibiotic prescription behaviour during 2 years. The main aims were: (i) to increase the percentage of prescriptions of penicillins for all RTIs treated with antibiotics; (ii) to increase the percentage of trimethoprim/sulfamethoxazole prescriptions for all uncomplicated lower UTIs treated with antibiotics; (iii) to decrease the percentage of quinolone prescriptions for all cases of exacerbated COPD (eCOPD) treated with antibiotics; and (iv) to decrease the proportion of sinusitis and other upper RTIs treated with antibiotics. The study was registered at ClinicalTrials.gov (NCT01358916). RESULTS: While the percentage of antibiotics prescribed for sinusitis or other upper RTIs and the percentage of quinolones prescribed for eCOPD did not differ between the intervention group and the control group, there was a significant increase in the percentage of prescriptions of penicillins for all RTIs treated with antibiotics [57% versus 49%, OR=1.42 (95% CI 1.08-1.89), P=0.01] and in the percentage of trimethoprim/sulfamethoxazole prescriptions for all uncomplicated lower UTIs treated with antibiotics [35% versus 19%, OR=2.16 (95% CI 1.19-3.91), P=0.01] in the intervention group. CONCLUSIONS: In our setting, implementing guidelines, coupled with sustained individual feedback, was not able to reduce the proportion of sinusitis and other upper RTIs treated with antibiotics, but increased the use of recommended antibiotics for RTIs and UTIs, as defined by the guidelines.