44 research outputs found

    Fabry-Perot Bound States in the Continuum in an Anisotropic Photonic Crystal

    Full text link
    An anisotropic photonic crystal containing two anisotropic defect layers is considered. It is demonstrated that the system under can support a Fabry-Perot bound state in the continuum (FP-BIC). A fully analytic solution of the scattering problem as well as a condition for FP-BIC have been derived in the framework of the temporal coupled-mode theory

    Enhanced light absorption in Tamm metasurface with a bound state in the continuum

    Full text link
    We consider light absorption in a germanium grating placed on top of photonic-crystalline substrate. Such a system supports an optical Tamm state decoupled from the continuous spectrum with its frequency within the photonic band gap. We have demonstrated that application of the Tamm state makes in possible to engineer extremely narrow absorber which provides a 100% absorption in a semiconductor grating in the critical coupling regime. The proposed design may be used at both normal and oblique incidence at the telecom wavelength

    Hinton, Deane R.

    Get PDF
    The chiral optical Tamm state (COTS) is a special localized state at the interface of a handedness-preserving mirror and a structurally chiral medium such as a cholesteric liquid crystal or a chiral sculptured thin film. The spectral behavior of COTS, observed as reflection resonances, is described by the temporal coupled-mode theory. Mode coupling is different for two circular light polarizations because COTS has a helix structure replicating that of the cholesteric. The mode coupling for co-handed circularly polarized light exponentially attenuates with the cholesteric layer thickness since the COTS frequency falls into the stop band. Cross-handed circularly polarized light freely goes through the cholesteric layer and can excite COTS when reflected from the handedness-preserving mirror. The coupling in this case is proportional to anisotropy of the cholesteric and theoretically it is only anisotropy of magnetic permittivity that can ultimately cancel this coupling. These two couplings being equal results in a polarization crossover (the Kopp--Genack effect) for which a linear polarization is optimal to excite COTS. The corresponding cholesteric thickness and scattering matrix for COTS are generally described by simple expressions

    Мінімізація опору персоналу організаційним змінам на підприємстві

    Get PDF
    Обґрунтовано підходи до мінімізації опору персоналу організаційним змінам на підприємстві. На основі аналізу недоліків існуючих підходів запропоновано концептуальні положення мінімізації опору персоналу організаційним змінам на підприємствах, у рамках реалізації яких розроблено підхід до оцінки рівня підтримки організаційних змін у колективі після інформаційної взаємодії між співробітниками та підхід до прийняття рішень у сфері управління мінімізацією опору персоналу організаційним змінам на підприємстві, що базується на оптимізаційній моделі вибору оптимальних рішень. Здійснено практичну апробацію запропонованих підходів на діючому промисловому підприємстві та сформульовано перспективи подальших досліджень.Обоснованы подходы к минимизации сопротивления персонала организационным изменениям на предприятии. На основе анализа недостатков существующих подходов предложены концептуальные положения минимизации сопротивления персонала организационным изменениям на предприятиях, в рамках реализации которых разработаны подход к оценке уровня поддержки организационных изменений в коллективе после информационного взаимодействия между сотрудниками и подход к принятию решений в сфере управления минимизацией сопротивления персонала организационным изменениям на предприятии, базирующийся на оптимизационной модели выбора оптимальных решений. Осуществлена практическая апробация предложенных подходов на действующем промышленном предприятии и сформулированы перспективы дальнейших исследований.The article is devoted to substantiating the approaches to minimizing the resistance of staff to organizational changes at an enterprise. It was revealed that existing scientific approaches do not allow formalizing the assessment of organizational resistance and minimizing the costs of preventing organizational resistance; they do not take into account such important factors as the authority of the members of the staff, objective benefits of a decision for the staff members and their inclination to adopt other people’s opinions. They do not allow assessing the staff members support for organizational change taking into account the information interaction between them. Based on the analysis of the shortcomings of existing approaches conceptual positions to minimizing the resistance of staff to organizational changes at enterprises were proposed, as part of which an approach was developed to assessing the level of support for organizational changes by the staff after the information interaction between the staff members, as well as an approach to managing the minimization of staff resistance to organizational changes at an enterprise based on the optimization model of optimal (in terms of cost and results) decisions. In terms of decision-making, the main task is the choice of optimal measures (interventions) that work through changing the objective benefits of the decisions and the initial level of support. A practical approbation of the proposed approaches at an existing industrial enterprise was carried out, and perspectives for further research were formulated. Prospects for further research are in the development of tools for minimizing organizational resistance and developing methods for assessing the characteristics of workers

    Consensus statement from the 2014 International Microdialysis Forum.

    Get PDF
    Microdialysis enables the chemistry of the extracellular interstitial space to be monitored. Use of this technique in patients with acute brain injury has increased our understanding of the pathophysiology of several acute neurological disorders. In 2004, a consensus document on the clinical application of cerebral microdialysis was published. Since then, there have been significant advances in the clinical use of microdialysis in neurocritical care. The objective of this review is to report on the International Microdialysis Forum held in Cambridge, UK, in April 2014 and to produce a revised and updated consensus statement about its clinical use including technique, data interpretation, relationship with outcome, role in guiding therapy in neurocritical care and research applications.We gratefully acknowledge financial support for participants as follows: P.J.H. - National Institute for Health Research (NIHR) Professorship and the NIHR Biomedical Research Centre, Cambridge; I.J. – Medical Research Council (G1002277 ID 98489); A. H. - Medical Research Council, Royal College of Surgeons of England; K.L.H.C. - NIHR Biomedical Research Centre, Cambridge (Neuroscience Theme; Brain Injury and Repair Theme); M.G.B. - Wellcome Trust Dept Health Healthcare Innovation Challenge Fund (HICF-0510-080); L. H. - The Swedish Research Council, VINNOVA and Uppsala Berzelii Technology Centre for Neurodiagnostics; S. M. - Fondazione IRCCS Cà Granda Ospedale Maggiore Policlinico; D.K.M. - NIHR Senior Investigator Award to D.K.M., NIHR Cambridge Biomedical Research Centre (Neuroscience Theme), FP7 Program of the European Union; M. O. - Swiss National Science Foundation and the Novartis Foundation for Biomedical Research; J.S. - Fondo de Investigación Sanitaria (Instituto de Salud Carlos III) (PI11/00700) co-financed by the European Regional Development; M.S. – NIHR University College London Hospitals Biomedical Research Centre; N. S. - Fondazione IRCCS Cà Granda Ospedale Maggiore Policlinico.This is the final version of the article. It first appeared from Springer via http://dx.doi.org/10.1007/s00134-015-3930-

    Trial of Decompressive Craniectomy for Traumatic Intracranial Hypertension.

    Get PDF
    BACKGROUND: The effect of decompressive craniectomy on clinical outcomes in patients with refractory traumatic intracranial hypertension remains unclear. METHODS: From 2004 through 2014, we randomly assigned 408 patients, 10 to 65 years of age, with traumatic brain injury and refractory elevated intracranial pressure (>25 mm Hg) to undergo decompressive craniectomy or receive ongoing medical care. The primary outcome was the rating on the Extended Glasgow Outcome Scale (GOS-E) (an 8-point scale, ranging from death to "upper good recovery" [no injury-related problems]) at 6 months. The primary-outcome measure was analyzed with an ordinal method based on the proportional-odds model. If the model was rejected, that would indicate a significant difference in the GOS-E distribution, and results would be reported descriptively. RESULTS: The GOS-E distribution differed between the two groups (P<0.001). The proportional-odds assumption was rejected, and therefore results are reported descriptively. At 6 months, the GOS-E distributions were as follows: death, 26.9% among 201 patients in the surgical group versus 48.9% among 188 patients in the medical group; vegetative state, 8.5% versus 2.1%; lower severe disability (dependent on others for care), 21.9% versus 14.4%; upper severe disability (independent at home), 15.4% versus 8.0%; moderate disability, 23.4% versus 19.7%; and good recovery, 4.0% versus 6.9%. At 12 months, the GOS-E distributions were as follows: death, 30.4% among 194 surgical patients versus 52.0% among 179 medical patients; vegetative state, 6.2% versus 1.7%; lower severe disability, 18.0% versus 14.0%; upper severe disability, 13.4% versus 3.9%; moderate disability, 22.2% versus 20.1%; and good recovery, 9.8% versus 8.4%. Surgical patients had fewer hours than medical patients with intracranial pressure above 25 mm Hg after randomization (median, 5.0 vs. 17.0 hours; P<0.001) but had a higher rate of adverse events (16.3% vs. 9.2%, P=0.03). CONCLUSIONS: At 6 months, decompressive craniectomy in patients with traumatic brain injury and refractory intracranial hypertension resulted in lower mortality and higher rates of vegetative state, lower severe disability, and upper severe disability than medical care. The rates of moderate disability and good recovery were similar in the two groups. (Funded by the Medical Research Council and others; RESCUEicp Current Controlled Trials number, ISRCTN66202560 .).Supported by the Medical Research Council (MRC) and managed by the National Institute for Health Research (NIHR) on behalf of the MRC–NIHR partnership (grant no. 09/800/16), and by the NIHR Cambridge Biomedical Research Centre, the Academy of Medical Sciences and Health Foundation (Senior Fellowship, to Dr. Hutchinson), and the Evelyn Trust. Dr. Hutchinson is supported by a Research Professorship from the NIHR, the NIHR Cambridge Biomedical Research Centre, a European Union Seventh Framework Program grant (CENTER-TBI; grant no. 602150), and the Royal College of Surgeons of England; Dr. Kolias, by a Royal College of Surgeons of England Research Fellowship and a Sackler Studentship; Dr. Pickard, by the NIHR Brain Injury Healthcare Technology Co-operative and a Senior Investigator award from the NIHR; and Dr. Menon, by a Senior Investigator award from the NIHR and a European Union Seventh Framework Program grant (CENTER-TBI; grant no. 602150). The University of Cambridge and Cambridge University Hospitals NHS Foundation Trust were the trial sponsors.This is the author accepted manuscript. The final version is available from the Massachusetts Medical Society via http://dx.doi.org/10.1056/NEJMoa160521

    Consensus statement from the 2014 International Microdialysis Forum

    Get PDF
    This is the final version of the article. It first appeared from Springer via http://dx.doi.org/10.1007/s00134-015-3930-yMicrodialysis enables the chemistry of the extracellular interstitial space to be measured. Use of this technique in patients with acute brain injury has increased our understanding of the pathophysiology of several acute neurological disorders. In 2004 a consensus document on the clinical application of cerebral microdialysis was published. Since then there have been significant advances in the clinical use of microdialysis in neurocritical care. The objective of this review is to report on the International Microdialysis Forum held in Cambridge, UK, in April 2014 and to produce a revised and updated consensus statement about its clinical use including technique, data interpretation, relationship with outcome, role in guiding therapy in neurocritical care and research applications.We gratefully acknowledge financial support for participants as follows: P.J.H. - National Institute for Health Research (NIHR) Professorship and the NIHR Biomedical Research Centre, Cambridge; I.J. ? Medical Research Council (G1002277 ID 98489); A. H. - Medical Research Council, Royal College of Surgeons of England; K.L.H.C. - NIHR Biomedical Research Centre, Cambridge (Neuroscience Theme; Brain Injury and Repair Theme); M.G.B. - Wellcome Trust Dept Health Healthcare Innovation Challenge Fund (HICF-0510-080); L. H. - The Swedish Research Council, VINNOVA and Uppsala Berzelii Technology Centre for Neurodiagnostics; S. M. - Fondazione IRCCS C? Granda Ospedale Maggiore Policlinico; D.K.M. - NIHR Senior Investigator Award to D.K.M., NIHR Cambridge Biomedical Research Centre (Neuroscience Theme), FP7 Program of the European Union; M. O. - Swiss National Science Foundation and the Novartis Foundation for Biomedical Research; J.S. - Fondo de Investigaci?n Sanitaria (Instituto de Salud Carlos III) (PI11/00700) co-financed by the European Regional Development; M.S. ? NIHR University College London Hospitals Biomedical Research Centre; N. S. - Fondazione IRCCS C? Granda Ospedale Maggiore Policlinico
    corecore