357 research outputs found

    Recreation, tourism and nature in a changing world : proceedings of the fifth international conference on monitoring and management of visitor flows in recreational and protected areas : Wageningen, the Netherlands, May 30-June 3, 2010

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    Proceedings of the fifth international conference on monitoring and management of visitor flows in recreational and protected areas : Wageningen, the Netherlands, May 30-June 3, 201

    Regulatory Compliance in Multi-Tier Supplier Networks

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    Over the years, avionics systems have increased in complexity to the point where 1st tier suppliers to an aircraft OEM find it financially beneficial to outsource designs of subsystems to 2nd tier and at times to 3rd tier suppliers. Combined with challenging schedule and budgetary pressures, the environment in which safety-critical systems are being developed introduces new hurdles for regulatory agencies and industry. This new environment of both complex systems and tiered development has raised concerns in the ability of the designers to ensure safety considerations are fully addressed throughout the tier levels. This has also raised questions about the sufficiency of current regulatory guidance to ensure: proper flow down of safety awareness, avionics application understanding at the lower tiers, OEM and 1st tier oversight practices, and capabilities of lower tier suppliers. Therefore, NASA established a research project to address Regulatory Compliance in a Multi-tier Supplier Network. This research was divided into three major study efforts: 1. Describe Modern Multi-tier Avionics Development 2. Identify Current Issues in Achieving Safety and Regulatory Compliance 3. Short-term/Long-term Recommendations Toward Higher Assurance Confidence This report presents our findings of the risks, weaknesses, and our recommendations. It also includes a collection of industry-identified risks, an assessment of guideline weaknesses related to multi-tier development of complex avionics systems, and a postulation of potential modifications to guidelines to close the identified risks and weaknesses

    Biological Control of Dutch Elm Disease

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    Introduction Elms are important trees in urban environments and coastal areas due to their resistance to harsh conditions such as wind, salt, flood, and narrow root space, as well as to their attractive architecture. However, a devastating disease, the so-called Dutch elm disease (DED), appeared in Europe during the 1920s and in North America by 1930. Sudden wilting and dying of the leaves and branches was caused by Ophiostoma ulmi during the first pandemic from 1920s to 1940s, while an even more aggressive strain O. novo-ulmi is responsible for the current pandemic. Elm bark beetles, mainly Scolytus scolytus and S. multistriatus, transmit the disease by breeding in weakened and dead elms (Scheffer et al, 2008). Approximately 100 years after its first introduction into Europe, biological control of Dutch elm disease is an effective component of an integrated control strategy for this disease. Conidiospores of Verticillium albo-atrum isolate WCS850 (active ingredient of Dutch Trig®) enhance the natural defence mechanism of elms after being injected in the xylem tissue of tree, where they germinate and induces resistance (Scheffer, 1990). The isolate was proven to be non-pathogenic for all the 19 tree species that had been tested (http://www.dutchtrig.com/home

    Clinical information modeling processes for semantic interoperability of electronic health records: systematic review and inductive analysis

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    This is a pre-copyedited, author-produced PDF of an article accepted for publication in Journal of the American Medical Informatics Association following peer review. The version of record is available online at: http://dx.doi.org/10.1093/jamia/ocv008[EN] [Objective] This systematic review aims to identify and compare the existing processes and methodologies that have been published in the literature for defining clinical information models (CIMs) that support the semantic interoperability of electronic health record (EHR) systems. [Material and Methods] Following the preferred reporting items for systematic reviews and meta-analyses systematic review methodology, the authors reviewed published papers between 2000 and 2013 that covered that semantic interoperability of EHRs, found by searching the PubMed, IEEE Xplore, and ScienceDirect databases. Additionally, after selection of a final group of articles, an inductive content analysis was done to summarize the steps and methodologies followed in order to build CIMs described in those articles. [Results] Three hundred and seventy-eight articles were screened and thirty six were selected for full review. The articles selected for full review were analyzed to extract relevant information for the analysis and characterized according to the steps the authors had followed for clinical information modeling. [Discussion] Most of the reviewed papers lack a detailed description of the modeling methodologies used to create CIMs. A representative example is the lack of description related to the definition of terminology bindings and the publication of the generated models. However, this systematic review confirms that most clinical information modeling activities follow very similar steps for the definition of CIMs. Having a robust and shared methodology could improve their correctness, reliability, and quality. [Conclusion] Independently of implementation technologies and standards, it is possible to find common patterns in methods for developing CIMs, suggesting the viability of defining a unified good practice methodology to be used by any clinical information modeler.This research has been partially funded by the Instituto de Salud Carlos III (Platform for Innovation in Medical Technologies and Health), grant PT13/0006/0036 and the Spanish Ministry of Economy and Competitiveness, grants TIN2010-21388-C02-01 and PTQ-12-05620.Moreno-Conde, A.; Moner Cano, D.; Da Cruz, WD.; Santos, MR.; Maldonado Segura, JA.; Robles Viejo, M.; Kalra, D. (2015). Clinical information modeling processes for semantic interoperability of electronic health records: systematic review and inductive analysis. Journal of the American Medical Informatics Association. 22(4):925-934. https://doi.org/10.1093/jamia/ocv008S925934224Goossen W Goossen-Baremans A van der Zel M . Detailed clinical models: a review. Healthc Inform Res. 2010;16:201.Beeler, G. W. (1998). HL7 Version 3—An object-oriented methodology for collaborative standards development1Presented at the International Medical Informatics Association Working Group 16 Conference on Standardisation in Medical Informatics—Towards International Consensus and Cooperation, Bermuda, 12 September, 1997.1. International Journal of Medical Informatics, 48(1-3), 151-161. doi:10.1016/s1386-5056(97)00121-4Dolin, R. H., Alschuler, L., Boyer, S., Beebe, C., Behlen, F. M., Biron, P. V., & Shabo (Shvo), A. (2006). HL7 Clinical Document Architecture, Release 2. 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Editorial principles for the development of standards for the structure and content of health records. 2012. https://www.rcplondon.ac.uk/sites/default/files/documents/editorial-principles-for-the-development-of-record-standards.pdf . Accessed July 18, 2015.Yuksel, M., & Dogac, A. (2011). Interoperability of Medical Device Information and the Clinical Applications: An HL7 RMIM based on the ISO/IEEE 11073 DIM. IEEE Transactions on Information Technology in Biomedicine, 15(4), 557-566. doi:10.1109/titb.2011.2151868Nagy M Hanzlicek P Precková P . Semantic interoperability in Czech healthcare environment supported by HL7 version 3. Methods Inf Med. 2010;49:186.LOPEZ, D., & BLOBEL, B. (2009). A development framework for semantically interoperable health information systems. International Journal of Medical Informatics, 78(2), 83-103. doi:10.1016/j.ijmedinf.2008.05.009Lopez DM Blobel B . Enhanced semantic interoperability by profiling health informatics standards. Methods Inf Med. 2009;48:170–177.Lopez DM Blobel B . Enhanced semantic interpretability by healthcare standards profiling. Stud Health Technol Inform. 2008;136:735.Knaup, P., Garde, S., & Haux, R. (2007). Systematic planning of patient records for cooperative care and multicenter research. International Journal of Medical Informatics, 76(2-3), 109-117. doi:10.1016/j.ijmedinf.2006.08.002Goossen, W. T. F., Ozbolt, J. G., Coenen, A., Park, H.-A., Mead, C., Ehnfors, M., & Marin, H. F. (2004). Development of a Provisional Domain Model for the Nursing Process for Use within the Health Level 7 Reference Information Model. Journal of the American Medical Informatics Association, 11(3), 186-194. doi:10.1197/jamia.m1085Anderson, H. V., Weintraub, W. S., Radford, M. J., Kremers, M. S., Roe, M. T., Shaw, R. E., … Tcheng, J. E. (2013). Standardized Cardiovascular Data for Clinical Research, Registries, and Patient Care. Journal of the American College of Cardiology, 61(18), 1835-1846. doi:10.1016/j.jacc.2012.12.047Jian, W.-S., Hsu, C.-Y., Hao, T.-H., Wen, H.-C., Hsu, M.-H., Lee, Y.-L., … Chang, P. (2007). Building a portable data and information interoperability infrastructure—framework for a standard Taiwan Electronic Medical Record Template. Computer Methods and Programs in Biomedicine, 88(2), 102-111. doi:10.1016/j.cmpb.2007.07.014Spigolon, D. N., & Moro, C. M. C. (2012). Arquétipos do conjunto de dados essenciais de enfermagem para atendimento de portadoras de endometriose. Revista Gaúcha de Enfermagem, 33(4), 22-32. doi:10.1590/s1983-14472012000400003Späth, M. B., & Grimson, J. (2011). Applying the archetype approach to the database of a biobank information management system. International Journal of Medical Informatics, 80(3), 205-226. doi:10.1016/j.ijmedinf.2010.11.002Smith, K., & Kalra, D. (2008). Electronic health records in complementary and alternative medicine. International Journal of Medical Informatics, 77(9), 576-588. doi:10.1016/j.ijmedinf.2007.11.005Bax, M. P., Kalra, D., & Santos, M. R. (2012). Dealing with the Archetypes Development Process for a Regional EHR System. Applied Clinical Informatics, 03(03), 258-275. doi:10.4338/aci-2011-12-ra-0074Moner D Moreno A Maldonado JA . Using archetypes for defining CDA templates. Stud Health Technol Inform. 2012;180:53–57.Moner D Maldonado JA Boscá D . CEN EN13606 normalisation framework implementation experiences. In: Seamless Care, Safe Care: The Challenges of Interoperability and Patient Safety in Health Care: Proceedings of the EFMI Special Topic Conference, June 2–4, 2010; Reykjavik, Iceland. IOS Press; 2010: 136.Marcos, M., Maldonado, J. A., Martínez-Salvador, B., Boscá, D., & Robles, M. (2013). Interoperability of clinical decision-support systems and electronic health records using archetypes: A case study in clinical trial eligibility. Journal of Biomedical Informatics, 46(4), 676-689. doi:10.1016/j.jbi.2013.05.004Leslie H . International developments in openEHR archetypes and templates. Health Inf Manag J. 2008;37:38.Kohl CD Garde S Knaup P . Facilitating secondary use of medical data by using openEHR archetypes. Stud Health Technol Inform. 2009;160:1117–1121.Garde, S., Hovenga, E., Buck, J., & Knaup, P. (2007). Expressing clinical data sets with openEHR archetypes: A solid basis for ubiquitous computing. International Journal of Medical Informatics, 76, S334-S341. doi:10.1016/j.ijmedinf.2007.02.004Garcia D Moro CM Cicogna PE . Method to integrate clinical guidelines into the electronic health record (EHR) by applying the archetypes approach. Stud Health Technol Inform. 2012;192:871–875.Duftschmid, G., Rinner, C., Kohler, M., Huebner-Bloder, G., Saboor, S., & Ammenwerth, E. (2013). The EHR-ARCHE project: Satisfying clinical information needs in a Shared Electronic Health Record System based on IHE XDS and Archetypes. International Journal of Medical Informatics, 82(12), 1195-1207. doi:10.1016/j.ijmedinf.2013.08.002Dias, R. D., Cook, T. W., & Freire, S. M. (2011). Modeling healthcare authorization and claim submissions using the openEHR dual-model approach. BMC Medical Informatics and Decision Making, 11(1). doi:10.1186/1472-6947-11-60Buck, J., Garde, S., Kohl, C. D., & Knaup-Gregori, P. (2009). Towards a comprehensive electronic patient record to support an innovative individual care concept for premature infants using the openEHR approach. International Journal of Medical Informatics, 78(8), 521-531. doi:10.1016/j.ijmedinf.2009.03.001Puentes, J., Roux, M., Montagner, J., & Lecornu, L. (2012). Development framework for a patient-centered record. Computer Methods and Programs in Biomedicine, 108(3), 1036-1051. doi:10.1016/j.cmpb.2012.06.007Liu, D., Wang, X., Pan, F., Yang, P., Xu, Y., Tang, X., … Rao, K. (2010). Harmonization of health data at national level: A pilot study in China. International Journal of Medical Informatics, 79(6), 450-458. doi:10.1016/j.ijmedinf.2010.03.002Liu, D., Wang, X., Pan, F., Xu, Y., Yang, P., & Rao, K. (2008). Web-based infectious disease reporting using XML forms. International Journal of Medical Informatics, 77(9), 630-640. doi:10.1016/j.ijmedinf.2007.10.011Kim, Y., & Park, H.-A. (2011). Development and Validation of Detailed Clinical Models for Nursing Problems in Perinatal care. Applied Clinical Informatics, 02(02), 225-239. doi:10.4338/aci-2011-01-ra-0007Khan, W. A., Hussain, M., Afzal, M., Amin, M. B., Saleem, M. A., & Lee, S. (2013). Personalized-Detailed Clinical Model for Data Interoperability Among Clinical Standards. Telemedicine and e-Health, 19(8), 632-642. doi:10.1089/tmj.2012.0189Jing, X., Kay, S., Marley, T., Hardiker, N. R., & Cimino, J. J. (2012). Incorporating personalized gene sequence variants, molecular genetics knowledge, and health knowledge into an EHR prototype based on the Continuity of Care Record standard. Journal of Biomedical Informatics, 45(1), 82-92. doi:10.1016/j.jbi.2011.09.001Hsu, W., Taira, R. K., El-Saden, S., Kangarloo, H., & Bui, A. A. T. (2012). Context-Based Electronic Health Record: Toward Patient Specific Healthcare. IEEE Transactions on Information Technology in Biomedicine, 16(2), 228-234. doi:10.1109/titb.2012.2186149Hoy D Hardiker NR McNicoll IT . Collaborative development of clinical templates as a national resource. Int J Med Inf. 2009;78:S3–S8.Buyl, R., & Nyssen, M. (2009). Structured electronic physiotherapy records. International Journal of Medical Informatics, 78(7), 473-481. doi:10.1016/j.ijmedinf.2009.02.007D’Amore JD Mandel JC Kreda DA . 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    Excitonic recombination dynamics in shallow quantum wells

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    We report a comprehensive study of carrier-recombination dynamics in shallow AlxGa1-xAs/GaAs quantum wells. At low crystal temperature (2 K), the excitonic radiative recombination time is shown to be strongly enhanced in shallow quantum wells with x>0.01, consistently with a model that takes into account the thermal equilibrium between the three-dimensional exciton gas of the barrier and the two-dimensional exciton gas, which are closer in energy as x decreases. Furthermore, we demonstrate the existence of a thermally activated escape mechanism due to the low effective barrier height in these structures. The nonradiative recombination is shown to dominate the carrier dynamics for temperatures as low as 10 K for x≈0.01. Our experimental observations are analyzed using three different variational exciton calculations. In particular, we study the crossover from the two-dimensional to the three-dimensional behavior of the exciton, which occurs for x as low as 0.01 and affects mainly the oscillator strength, whereas the transition energies in shallow quantum wells can be calculated, to a large extent, using the same approximations as for conventional quantum wells. The peculiar behavior of the oscillator strength at the crossover to the weak confinement regime is obtained by expansion in a large basis

    Icodextrin Versus Glucose Solutions for the Once-Daily Long Dwell in Peritoneal Dialysis: An Enriched Systematic Review and Meta-analysis of Randomized Controlled Trials

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    Rationale & Objective The efficacy and safety of icodextrin versus glucose-only peritoneal dialysis (PD) regimens is unclear. The aim of this study was to compare once-daily long-dwell icodextrin versus glucose among patients with kidney failure undergoing PD. Study Design Systematic review of randomized controlled trials (RCTs), enriched with unpublished data from investigator-initiated and industry-sponsored studies. Setting & Study Populations Individuals with kidney failure receiving regular PD treatment enrolled in clinical trials of dialysate composition. Selection Criteria for Studies Medline, Embase, CENTRAL, Ichushi Web, 10 Chinese databases, clinical trials registries, conference proceedings, and citation lists from inception to November 2018. Further data were obtained from principal investigators and industry clinical study reports. Data Extraction 2 independent reviewers selected studies and extracted data using a prespecified extraction instrument. Analytic Approach Qualitative synthesis of demographics, measurement scales, and outcomes. Quantitative synthesis with Mantel-Haenszel risk ratios (RRs), Peto odds ratios (ORs), or (standardized) mean differences (MDs). Risk of bias of included studies at the outcome level was assessed using the Cochrane risk-of-bias tool for RCTs. Results 19 RCTs that enrolled 1,693 participants were meta-analyzed. Ultrafiltration was improved with icodextrin (medium-term MD, 208.92 [95% CI, 99.69-318.14] mL/24 h; high certainty of evidence), reflected also by fewer episodes of fluid overload (RR, 0.43 [95% CI, 0.24-0.78]; high certainty). Icodextrin-containing PD probably decreased mortality risk compared to glucose-only PD (Peto OR, 0.49 [95% CI, 0.24-1.00]; moderate certainty). Despite evidence of lower peritoneal glucose absorption with icodextrin-containing PD (medium-term MD, −40.84 [95% CI, −48.09 to −33.59] g/long dwell; high certainty), this did not directly translate to changes in fasting plasma glucose (−0.50 [95% CI, −1.19 to 0.18] mmol/L; low certainty) and hemoglobin A1c levels (−0.14% [95% CI, −0.34% to 0.05%]; high certainty). Safety outcomes and residual kidney function were similar in both groups; health-related quality-of-life and pain scores were inconclusive. Limitations Trial quality was variable. The follow-up period was heterogeneous, with a paucity of assessments over the long term. Mortality results are based on just 32 events and were not corroborated using time-to-event analysis of individual patient data. Conclusions Icodextrin for once-daily long-dwell PD has clinical benefit for some patients, including those not meeting ultrafiltration targets and at risk for fluid overload. Future research into patient-centered outcomes and cost-effectiveness associated with icodextrin is needed

    The Extent and Coverage of Current Knowledge of Connected Health: Systematic Mapping Study

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    Background: This paper examines the development of the Connected Health research landscape with a view on providing a historical perspective on existing Connected Health research. Connected Health has become a rapidly growing research field as our healthcare system is facing pressured to become more proactive and patient centred. Objective: We aimed to identify the extent and coverage of the current body of knowledge in Connected Health. With this, we want to identify which topics have drawn the attention of Connected health researchers, and if there are gaps or interdisciplinary opportunities for further research. Methods: We used a systematic mapping study that combines scientific contributions from research on medicine, business, computer science and engineering. We analyse the papers with seven classification criteria, publication source, publication year, research types, empirical types, contribution types research topic and the condition studied in the paper. Results: Altogether, our search resulted in 208 papers which were analysed by a multidisciplinary group of researchers. Our results indicate a slow start for Connected Health research but a more recent steady upswing since 2013. The majority of papers proposed healthcare solutions (37%) or evaluated Connected Health approaches (23%). Case studies (28%) and experiments (26%) were the most popular forms of scientific validation employed. Diabetes, cancer, multiple sclerosis, and heart conditions are among the most prevalent conditions studied. Conclusions: We conclude that Connected Health research seems to be an established field of research, which has been growing strongly during the last five years. There seems to be more focus on technology driven research with a strong contribution from medicine, but business aspects of Connected health are not as much studied

    The clinical presentation of preterm cerebellar haemorrhage

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    The objective of this study was to evaluate clinical symptoms and findings on cranial ultrasound (CUS) in preterm infants with cerebellar haemorrhage through retrospective analysis of all preterm infants with a postnatal CUS or MRI diagnosis of cerebellar haemorrhage admitted in a tertiary care centre between January 2002 and June 2009. Fifteen infants were identified; median gestational age was 25 2/7 weeks and median birth weight 730 g. We discerned six types of haemorrhage: subarachnoid (n=3), folial (n=1), lobar (n=9, of which 4 bilateral), giant lobar (n=1, including vermis) and contusional (n=1). Especially in infants with lobar cerebellar haemorrhage, CUS showed preceding or concurrent lateral ventricle dilatation, mostly without intraventricular haemorrhage (IVH). Thirteen infants suffered from notable, otherwise unexplained motor agitation in the days preceding the diagnosis. In conclusion, motor agitation may be a presenting symptom of cerebellar haemorrhage in preterm infants. Unexplained ventriculomegaly can be a first sign of cerebellar haemorrhage and should instigate sonographic exploration of the cerebellum

    Nucleophile-Catalyzed Additions to Activated Triple Bonds. Protection of Lactams, Imides, and Nucleosides with MocVinyl and Related Groups

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    Additions of lactams, imides, (S)-4-benzyl-1,3-oxazolidin-2-one, 2-pyridone, pyrimidine-2,4-diones (AZT derivatives), or inosines to the electron-deficient triple bonds of methyl propynoate, tert-butyl propynoate, 3-butyn-2-one, N-propynoylmorpholine, or N-methoxy-N-methylpropynamide in the presence of many potential catalysts were examined. DABCO and, second, DMAP appeared to be the best (highest reaction rates and E/Z ratios), while RuCl3, RuClCp*(PPh3)2, AuCl, AuCl(PPh3), CuI, and Cu2(OTf)2 were incapable of catalyzing such additions. The groups incorporated (for example, the 2-(methoxycarbonyl)ethenyl group that we name MocVinyl) serve as protecting groups for the above-mentioned heterocyclic CONH or CONHCO moieties. Deprotections were accomplished via exchange with good nucleophiles: the 1-dodecanethiolate anion turned out to be the most general and efficient reagent, but in some particular cases other nucleophiles also worked (e.g., MocVinyl-inosines can be cleaved with succinimide anion). Some structural and mechanistic details have been accounted for with the help of DFT and MP2 calculations
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