22 research outputs found
Multiple extraordinary optical transmission peaks from evanescent coupling in perforated metal plates surrounded by dielectrics
© 2010 Optical Society of America. One print or electronic copy may be made for personal use only.
Systematic reproduction and distribution, duplication of any material in this paper for a fee or for commercial purposes, or modifications of the content of this paper are prohibitedWe study numerically and theoretically the optical transmission of nanostructured gold films embedded in dielectric claddings. We show how multiple transmission peaks appear as the claddings thickness increases. These transmission peaks come not only from surface plasmon polariton excitations but also from the excitation of Fabry-Perot modes sustained at the claddings, coupled through the metal, as long as a periodic pattern is milled in the metal film. We propose that this structure could be used as an ultracompact all-optical switch by surrounding the metal film with Kerr nonlinear dielectric layers. (C) 2010 Optical Society of AmericaWe thank the FCT (Fundacao para a Ciencia e Tecnologia) for funding of this research through the projects SFRH/BD/8278/2002 and PTDC/FIS/68419/2006.Ortuño Molinero, R.; GarcĂa Meca, C.; RodrĂguez Fortuño, FJ.; MartĂ Sendra, J.; MartĂnez Abietar, AJ. (2010). Multiple extraordinary optical transmission peaks from evanescent coupling in perforated metal plates surrounded by dielectrics. Optics Express. 18(8):7893-7898. https://doi.org/10.1364/OE.18.007893S78937898188Dragila, R., Luther-Davies, B., & Vukovic, S. (1985). High Transparency of Classically Opaque Metallic Films. Physical Review Letters, 55(10), 1117-1120. doi:10.1103/physrevlett.55.1117Ebbesen, T. W., Lezec, H. J., Ghaemi, H. F., Thio, T., & Wolff, P. A. (1998). Extraordinary optical transmission through sub-wavelength hole arrays. Nature, 391(6668), 667-669. doi:10.1038/35570Koerkamp, K. J. K., Enoch, S., Segerink, F. B., van Hulst, N. F., & Kuipers, L. (2004). Strong Influence of Hole Shape on Extraordinary Transmission through Periodic Arrays of Subwavelength Holes. Physical Review Letters, 92(18). doi:10.1103/physrevlett.92.183901Takakura, Y. (2001). Optical Resonance in a Narrow Slit in a Thick Metallic Screen. Physical Review Letters, 86(24), 5601-5603. doi:10.1103/physrevlett.86.5601Zhou, L., Wen, W., Chan, C. T., & Sheng, P. (2005). Electromagnetic-Wave Tunneling Through Negative-Permittivity Media with High Magnetic Fields. Physical Review Letters, 94(24). doi:10.1103/physrevlett.94.243905Lomakin, V., & Michielssen, E. (2005). Enhanced transmission through metallic plates perforated by arrays of subwavelength holes and sandwiched between dielectric slabs. Physical Review B, 71(23). doi:10.1103/physrevb.71.235117Rakić, A. D., Djurišić, A. B., Elazar, J. M., & Majewski, M. L. (1998). Optical properties of metallic films for vertical-cavity optoelectronic devices. Applied Optics, 37(22), 5271. doi:10.1364/ao.37.005271Genet, C., & Ebbesen, T. W. (2007). Light in tiny holes. Nature, 445(7123), 39-46. doi:10.1038/nature05350Ghaemi, H. F., Thio, T., Grupp, D. E., Ebbesen, T. W., & Lezec, H. J. (1998). Surface plasmons enhance optical transmission through subwavelength holes. Physical Review B, 58(11), 6779-6782. doi:10.1103/physrevb.58.6779MartĂnez, A., & MartĂ, J. (2005). Negative refraction in two-dimensional photonic crystals: Role of lattice orientation and interface termination. Physical Review B, 71(23). doi:10.1103/physrevb.71.235115Ruan, Z., & Qiu, M. (2006). Enhanced Transmission through Periodic Arrays of Subwavelength Holes: The Role of Localized Waveguide Resonances. Physical Review Letters, 96(23). doi:10.1103/physrevlett.96.233901Economou, E. N. (1969). Surface Plasmons in Thin Films. Physical Review, 182(2), 539-554. doi:10.1103/physrev.182.539Esembeson, B., Scimeca, M. L., Michinobu, T., Diederich, F., & Biaggio, I. (2008). A High-Optical Quality Supramolecular Assembly for Third-Order Integrated Nonlinear Optics. Advanced Materials, 20(23), 4584-4587. doi:10.1002/adma.200801552Spano, R., Daldosso, N., Cazzanelli, M., Ferraioli, L., Tartara, L., Yu, J., … Pavesi, L. (2009). Bound electronic and free carrier nonlinearities in Silicon nanocrystals at 1550nm. Optics Express, 17(5), 3941. doi:10.1364/oe.17.003941Dani, K. M., Ku, Z., Upadhya, P. C., Prasankumar, R. P., Brueck, S. R. J., & Taylor, A. J. (2009). Subpicosecond Optical Switching with a Negative Index Metamaterial. Nano Letters, 9(10), 3565-3569. doi:10.1021/nl901764
Impact of point-of-care pre-procedure creatinine and eGFR testing in patients with ST segment elevation myocardial infarction undergoing primary PCI: The pilot STATCREAT study
Background:
Contrast-induced acute kidney injury (CI-AKI) is a recognised complication during primary PCI that affects short and long term prognosis. The aim of this study was to assess the impact of point-of-care (POC) pre-PPCI creatinine and eGFR testing in STEMI patients.
Methods
160 STEMI patients (STATCREAT group) with pre-procedure POC testing of Cr and eGFR were compared with 294 consecutive retrospective STEMI patients (control group). Patients were further divided into subjects with or without pre-existing CKD.
Results:
The incidence of CI-AKI in the whole population was 14.5% and not different between the two overall groups. For patients with pre-procedure CKD, contrast dose was significantly reduced in the STATCREAT group (124.6 ml vs. 152.3 ml, p = 0.015). The incidence of CI-AKI was 5.9% (n = 2) in the STATCREAT group compared with 17.9% (n = 10) in the control group (p = 0.12). There was no difference in the number of lesions treated (1.118 vs. 1.196, p = 0.643) or stents used (1.176 vs. 1.250, p = 0.78). For non-CKD patients, there was no significant difference in contrast dose (172.4 ml vs. 158.4 ml, p = 0.067), CI-AKI incidence (16.7% vs. 13.4%, p = 0.4), treated lesions (1.167 vs. 1.164, p = 1.0) or stents used (1.214 vs. 1.168, p = 0.611) between the two groups.
Conclusions:
Pre-PPCI point-of-care renal function testing did not reduce the incidence of CI-AKI in the overall group of STEMI patients. In patients with CKD, contrast dose was significantly reduced, but a numerical reduction in CI-AKI was not found to be statistically significant. No significant differences were found in the non-CKD group
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Dermatitis, an approach from occupational medicine
Occupational dermatitis is one of the most common occupational diseases in clinical practice. Prevalence varies according to the job activities and types of exposure, with figures of up to 37% reported in the literature. Its origin may be irritant or allergic. Atopy and frequent hand washing or exposure to wetness or humidity is described has been described as risk factors, while evidence for gender and tobacco consumption, among others, is controversial. Diagnosis is based on physical examination, etiological patch testing and certification of occupational origin using standardized criteria. The condition has been associated with reduced productivity, absenteeism and occupational changes, as well as significant decreases in the quality of life of patients. Prevention is based primarily on education and restriction of exposure. These strategies are coupled with the treatment, which include the use of drugs such as topical steroids and calcineurin inhibitors.(X) Close Abstrac
Delirium in the hospital, a narrative review
Delirium is a common complication in hospitalized patients, particularly the elderly and those with cognitive impairment. It has been associated with higher mortality, prolonged hospitalization, cognitive impairment, higher rates of institutionalization at discharge and higher costs for healthcare systems. Its pathophysiology is poorly understood, and more recently a predominantly inflammatory origin has been proposed, which could explain its pervasiveness and association with underlying conditions. Clinically, it is characterized by acute onset with fluctuating course, inattention, disorganized thinking and altered level of consciousness. Diagnostic approach is based on the systematic search for triggering factors as well as the manifestations of the syndrome. Symptomatic treatment is based neuroleptics as first line treatment, and lorazepam when the former cannot be used or there are special indications. There is evidence that the condition can be prevented by resorting to multi-component strategies