Surface-plasmon-enhanced light scattering from microscopic spheres

Copyright © 2003 American Institute of Physics. This article may be downloaded for personal use only. Any other use requires prior permission of the author and the American Institute of Physics. The following article appeared in Applied Physics Letters 83 (2003) and may be found at http://link.aip.org/link/?APPLAB/83/3006/1The enhanced light scattering from microscopic latex spheres placed in the optical field associated with a surface-plasmon resonance is explored. Spheres of 200 nm diameter are placed on an optically thin gold film that supports the surface-plasmon and the scattered intensity is then measured as a function of scattering angle. This is compared to the scattering profiles obtained from spheres placed on a bare glass substrate. In both cases, the experimental data are compared to theory. This system is of interest in the field of optical biosensing

The Preference Clause Revisited: Central Lincoln Peoples\u27 Utility District v. Johnson and the Pacific Northwest Electric Power Planning and Conservation Act

This article analyzes the legislative development of the preference clause to its inclusion in the Pacific Northwest Electric Power Planning and Conservation Act (Northwest Power Act). This analysis demonstrates the Northwest Power Act\u27s reaffirmation of the supply preference traditionally included in federal power marketing legislation. The analysis also reveals a unique price discount for customers entitled to a supply preference under the Northwest Power Act. Additionally, the article considers recent Ninth Circuit decisions applying the preference clause to various forms of power allocation by federal agencies. The analysis identifies legislative and judicial adherence to the preference concept based on congressional confidence in the principles underlying the preference concept. The article concludes that Congress and the federal courts have strengthened the priority given to public utilities in the Pacific Northwest to federally generated electric power despite attempts to circumvent or erode preference rights

Relationship between photonic band structure and emission characteristics of a polymer distributed feedback laser

G. A. Turnbull, P. Andrew, M. J. Jory, William L. Barnes, and I. D. W. Samuel, Physical Review B, Vol. 64, article 125122 (2001). "Copyright © 2001 by the American Physical Society."We present an experimental study of the emission characteristics and photonic band structure of a distributed feedback polymer laser, based on the material poly[2-methoxy-5-(2′-ethylhexyloxy)-1,4-phenylene vinylene]. We use measurements of the photonic band dispersion to explain how the substrate microstructure modifies both spontaneous and stimulated emission. The lasing structure exhibits a one-dimensional photonic band gap around 610 nm, with lasing occurring at one of the two associated band edges. The band edge (frequency) selection mechanism is found to be a difference in the level of output coupling of the modes associated with the two band edges. This is a feature of the second-order distributed feedback mechanism we have employed and is clearly evident in the measured photonic band structur

Mycobacterium Avium Complex-Associated Vertebral Osteomyelitis in an Immunocompetent Patient: A Case Report

Introduction Mycobacterium avium complex (MAC) infection in the spine is extremely rare, with its pathogenesis and epidemiology remaining poorly understood. Clinically, MAC infections commonly present with pulmonary, musculoskeletal, and disseminated disease. Manifestation of MAC infections, specifically disseminated disease to the spine, is uncommon in patients without human immunodeficiency virus or acquired immune deficiency syndrome. Case Presentation In December 2017, a 46-year-old immunocompetent man presented with severe lower back pain, right lower extremity pain, and a previous L5-S1 fusion. Imaging revealed pseudarthrosis at L5-S1 with halos around S1 screws. In March 2018, he underwent revision surgery with partial relief and began outpatient physical therapy. After seven months, his symptoms recurred. MRI indicated a fluid collection at L5-S1. In October 2018, he underwent irrigation and debridement (I&D), removal of hardware (ROH), and revision fusion. Initial cultures were negative, and empiric PO and IV antibiotics were initiated. In January 2019, he presented to the hospital with intractable low back back and right lower extremity numbness. Follow-up MRI in January 2019 suggested a recurrent fluid collection, leading to subsequent surgical intervention. Acid-fast bacterial (AFB), blood, wound, fungal cultures and a biopsy with gram stain were initially negative and empiric IV antibiotics were initiated. Post-op course was complicated by leukocytosis and hyperthermia. Repeat MRI revealed migration of the fluid collection into L5-S1 disc space. MRI one week later showed no improvements, which lead to a revision laminectomy, ROH, I&D, and drain placement. Four days post-op and one month after initial cultures, AFB cultures grew MAC. Treatment was initiated with Ethambutol, Rifampin, and Clarithromycin for twelve to eighteen months. At one year post-op, there was no sign of infection on updated imaging. Discussion This unique case underscores the rare possibility of MAC being linked to vertebral osteomyelitis, particularly in immunocompetent patients. MAC cultures are slow growing and can take up to six weeks to develop mature colonies making it challenging to initially diagnose. While our patient was immunocompetent, he had a past medical history of underlying lung disease, COPD, which is the most important risk factor for patients without HIV. It was hypothesized that the source of infection was secondary to a previous oral tooth abscess the patient subsequently developed, however, his multiple previous surgeries could have also been the source. Due to its rarity and long incubation times, accurate and early diagnosis of MAC represents a major challenge. Physicians should consider MAC in patients with non-responsive or recurrent osteomyelitis to prevent delayed diagnosis and significant adverse outcomes

Surface-plasmon voltammetry using a gold grating

Using a sensitive optical wavelength modulation technique the surface-plasmon excited on a gold grating surface immersed in sulfuric acid is studied at the same time as cyclic voltammetry is undertaken. Because of the optical sensitivity of the modulation technique significant optical effects are observed at potentials well below those at which any gross oxidation effects occur.</jats:p

Measurements of the pp → ZZ production cross section and the Z → 4ℓ branching fraction, and constraints on anomalous triple gauge couplings at √s = 13 TeV

Four-lepton production in proton-proton collisions, pp -> (Z/gamma*)(Z/gamma*) -> 4l, where l = e or mu, is studied at a center-of-mass energy of 13 TeV with the CMS detector at the LHC. The data sample corresponds to an integrated luminosity of 35.9 fb(-1). The ZZ production cross section, sigma(pp -> ZZ) = 17.2 +/- 0.5 (stat) +/- 0.7 (syst) +/- 0.4 (theo) +/- 0.4 (lumi) pb, measured using events with two opposite-sign, same-flavor lepton pairs produced in the mass region 60 4l) = 4.83(-0.22)(+0.23) (stat)(-0.29)(+0.32) (syst) +/- 0.08 (theo) +/- 0.12(lumi) x 10(-6) for events with a four-lepton invariant mass in the range 80 4GeV for all opposite-sign, same-flavor lepton pairs. The results agree with standard model predictions. The invariant mass distribution of the four-lepton system is used to set limits on anomalous ZZZ and ZZ. couplings at 95% confidence level: -0.0012 < f(4)(Z) < 0.0010, -0.0010 < f(5)(Z) < 0.0013, -0.0012 < f(4)(gamma) < 0.0013, -0.0012 < f(5)(gamma) < 0.0013

UK framework for basic epilepsy training and oromucosal midazolam administration.

BACKGROUND: UK wide Oromucosal Midazolam is used as an emergency treatment in community for seizures administered by family/carers with the right training. The Joint Epilepsy Council (JEC) UK which produced the training guidelines disbanded in 2016. PURPOSE: Provide standards for basic epilepsy education and rescue medication (Midazolam) administration. METHODS: The Epilepsy Nurses Association (ESNA), The International League against Epilepsy, British Chapter (ILAE) and the Royal college of Psychiatrists (RCPsych), used the Delphi process to update guidelines for the administration of oromucosal midazolam including developing a voluntary on-line test for carers. During 2017-2019 a facilitator worked with two ESNA committees to update the existing guidance and another to develop a question-bank. Both committee outputs were circulated to the ESNA membership, then ILAE and RCPsych for review. Patient-facing organizations and charities' opinions were solicited. All feedback was assimilated. A private provider was contracted to deliver the test. RESULTS: A consensus process involving two task and finish groups of 19 people each compared, reflected, debated, and engaged with stakeholders across three stages. The updated ratified guidelines were circulated nationally. The Delphi process highlighted many regions and individuals had local assessment tools and procedures in place, while others (around 50%) had no assessment provision. 278 carers with a 95% pass-rate and 100% positive feedback have undertaken the online test (10/2020). CONCLUSION: The UK-wide care provision gap in basic epilepsy-training and safe rescue medication administration is now addressed. A two-yearly update to the guidelines and test is planned

Convergent evolution of toxin resistance in animals

Convergence is the phenomenon whereby similar phenotypes evolve independently in different lineages. One example is resistance to toxins in animals. Toxins have evolved many times throughout the tree of life. They disrupt molecular and physiological pathways in target species, thereby incapacitating prey or deterring a predator. In response, molecular resistance has evolved in many species exposed to toxins to counteract their harmful effects. Here, we review current knowledge on the convergence of toxin resistance using examples from a wide range of toxin families. We explore the evolutionary processes and molecular adaptations driving toxin resistance. However, resistance adaptations may carry a fitness cost if they disrupt the normal physiology of the resistant animal. Therefore, there is a trade‐off between maintaining a functional molecular target and reducing toxin susceptibility. There are relatively few solutions that satisfy this trade‐off. As a result, we see a small set of molecular adaptations appearing repeatedly in diverse animal lineages, a phenomenon that is consistent with models of deterministic evolution. Convergence may also explain what has been called ‘autoresistance’. This is often thought to have evolved for self‐protection, but we argue instead that it may be a consequence of poisonous animals feeding on toxic prey. Toxin resistance provides a unique and compelling model system for studying the interplay between trophic interactions, selection pressures and the molecular mechanisms underlying evolutionary novelties