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https://www.readbyqxmd.com/read/29437462/higher-dimensional-caustics-in-nonlinear-compton-scattering
#1
Vasily Yu Kharin, Daniel Seipt, Sergey G Rykovanov
A description of the spectral and angular distributions of Compton scattered light in collisions of intense laser pulses with high-energy electrons is unwieldy and usually requires numerical simulations. However, due to the large number of parameters affecting the spectra such numerical investigations can become computationally expensive. Using methods of catastrophe theory we predict higher-dimensional caustics in the spectra of the Compton scattered light, which are associated with bright narrow-band spectral lines, and in the simplest case can be controlled by the value of the linear chirp of the pulse...
January 26, 2018: Physical Review Letters
https://www.readbyqxmd.com/read/29427056/a-rare-case-of-anal-and-perianal-chemical-burn-in-a-child-due-to-potassium-permanganate-crystals
#2
Suvashis Dash, Jatin Bhojani, Sharadendu Sharma
Many chemicals used as medical treatments can cause chemical burns as an untoward side effect. One of such chemicals is potassium permanganate. It is a caustic chemical used as a disinfectant. The most common sites of burn by potassium permanganate are exposed sites like the face and hands. Chemical burns in the perianal and anal region are rare in clinical practice and even sparser in the pediatric age group. In this article, we report a case of perianal and anal chemical burn in an 18-month-old, male child, caused by potassium permanganate crystal applied wrongly for the treatment of pinworm infestation...
February 9, 2018: Drug Safety—Case Reports
https://www.readbyqxmd.com/read/29426216/bioreactors-for-oil-sands-process-affected-water-ospw-treatment-a-critical-review
#3
REVIEW
Jinkai Xue, Chunkai Huang, Yanyan Zhang, Yang Liu, Mohamed Gamal El-Din
Canada has the world's largest oil sands reservoirs. Surface mining and subsequent caustic hot water extraction of bitumen lead to an enormous quantity of tailings (volumetric ratio bitumen:water=9:1). Due to the zero-discharge approach and the persistency of the complex matrix, oil producers are storing oil sands tailings in vast ponds in Northern Alberta. Oil sands tailings are comprised of sand, clay and process-affected water (OSPW). OSPW contains an extremely complex matrix of organic contaminants (e.g...
February 2, 2018: Science of the Total Environment
https://www.readbyqxmd.com/read/29403130/suicidal-nonorganophosphate-poisoning-in-a-tertiary-hospital-in-south-india-nature-prevalence-risk-factors
#4
Rohit Ninan Benjamin, Thambu David, Ramya Iyadurai, K S Jacob
Background: People who deliberately ingest poisons commonly present to emergency departments of hospitals in India. However, there is a dearth of information on poisoning using nonorganophosphorus pesticides. Methods: This prospective, hospital-based study attempted to examine the nonorganophosphorus poisons used to attempt suicide. Data on sociodemographic characteristics of patients, site and source of poisons, co-ingested substances, premeditation, and reason for poisoning were collected...
January 2018: Indian Journal of Psychological Medicine
https://www.readbyqxmd.com/read/29400894/wavefronts-and-caustics-associated-with-mathieu-beams
#5
Israel Julián-Macías, Carolina Rickenstorff-Parrao, Omar de Jesús Cabrera-Rosas, Ernesto Espíndola-Ramos, Salvador Alejandro Juárez-Reyes, Paula Ortega-Vidals, Gilberto Silva-Ortigoza, Citlalli Teresa Sosa-Sánchez
In this work we compute the wavefronts and the caustics associated with the solutions to the scalar wave equation introduced by Durnin in elliptical cylindrical coordinates generated by the function A(ϕ)=ceν(ϕ,q)+iseν(ϕ,q), with ν being an integral or nonintegral number. We show that the wavefronts and the caustic are invariant under translations along the direction of evolution of the beam. We remark that the wavefronts of the separable Mathieu beams generated by A(ϕ)=ceν(ϕ,q) and A(ϕ)=seν(ϕ,q) are cones and their caustic is the z axis; thus, they are not structurally stable...
February 1, 2018: Journal of the Optical Society of America. A, Optics, Image Science, and Vision
https://www.readbyqxmd.com/read/29400893/hyperbolic-accelerating-beams-and-their-relation-with-hermite-gaussian-beams
#6
Chaohong Huang, Hanqing Li, Jianfeng Wu, Yupeng Yan
We derive the initial distributions of phase and complex amplitude of accelerating beams with arbitrary predesigned hyperbolic trajectories using the caustic-design method and explore the relation between these beams and Hermite-Gaussian beams. The results show the hyperbolic accelerating beams are a larger class of beams than Hermite-Gaussian beams. When the bending parameter is an integer, the hyperbolic accelerating beams have a similar initial complex amplitude distribution and almost the same propagating characteristics as Hermite-Gaussian beams...
February 1, 2018: Journal of the Optical Society of America. A, Optics, Image Science, and Vision
https://www.readbyqxmd.com/read/29355458/protein-a-resin-lifetime-study-evaluation-of-protein-a-resin-performance-with-a-model-based-approach-in-continuous-capture
#7
Ketki Behere, Bumjoon Cha, Seongkyu Yoon
A modified shrinking core model (MSCM) has been employed to describe the mechanism for the degradation of Protein A resin particles taking place under continuous chromatographic operation. The model is based on the hypothetical shrinkage of the boundary layer of the resin particles, which house the active Protein A ligands within their pores. It has been determined that caustic during the sanitization phase of chromatography primarily caused the Protein A ligand degradation. Protein A resins provided by manufacturers possess unique caustic stability which has been employed in MSCM to appraise the ligand degradation...
January 22, 2018: Preparative Biochemistry & Biotechnology
https://www.readbyqxmd.com/read/29349540/self-dilation-for-therapy-resistant-benign-esophageal-strictures-towards-a-systematic-approach
#8
Emo E van Halsema, Chantal A 't Hoen, Patricia S de Koning, Wilda D Rosmolen, Jeanin E van Hooft, Jacques J Bergman
BACKGROUND: Patients with therapy-resistant benign esophageal strictures (TRBES) suffer from chronic dysphagia and generally require repeated endoscopic dilations. For selected patients, esophageal self-dilation may improve patient's autonomy and reduce the number of endoscopic dilations. We evaluated the clinical course and outcomes of patients who started esophageal self-dilation at our institution. METHODS: This study was a retrospective case series of patients with TRBES who started esophageal self-dilation between 2012 and 2016 at the Academic Medical Center Amsterdam...
January 18, 2018: Surgical Endoscopy
https://www.readbyqxmd.com/read/29347522/semiclassical-catastrophe-theory-of-simple-bifurcations
#9
A G Magner, K Arita
The Fedoriuk-Maslov catastrophe theory of caustics and turning points is extended to solve the bifurcation problems by the improved stationary phase method (ISPM). The trace formulas for the radial power-law (RPL) potentials are presented by the ISPM based on the second- and third-order expansion of the classical action near the stationary point. A considerable enhancement of contributions of the two orbits (pair consisting of the parent and newborn orbits) at their bifurcation is shown. The ISPM trace formula is proposed for a simple bifurcation scenario of Hamiltonian systems with continuous symmetries, where the contributions of the bifurcating parent orbits vanish upon approaching the bifurcation point due to the reduction of the end-point manifold...
October 2017: Physical Review. E
https://www.readbyqxmd.com/read/29328086/geometric-optics-of-a-refringent-sphere-illuminated-by-a-point-source-caustics-wavefronts-and-zero-phase-fronts-for-every-rainbow-k-order
#10
Paul-Étienne Ouellette
This study relates to a refringent sphere illuminated by a point source placed at a distance h from its center; for h→∞ the light beam becomes parallel. A selection of variables, principally angular with the center of the sphere as a common point, allows a global, straightforward, and geometrically transparent way to the rays, caustics, and wavefronts, internal as well as external, for every k order, k being the number of internal reflections. One obtains compact formulas for generating the rays and the wavefronts...
January 1, 2018: Journal of the Optical Society of America. A, Optics, Image Science, and Vision
https://www.readbyqxmd.com/read/29315554/an-optical-configuration-for-fastidious-stem-detector-calibration-and-the-effect-of-the-objective-lens-pre-field
#11
L Jones, A Varambhia, H Sawada, P D Nellist
In the scanning transmission electron microscope, an accurate knowledge of detector collection angles is paramount in order to quantify signals on an absolute scale. Here we present an optical configuration designed for the accurate measurement of collection angles for both image-detectors and energy-loss spectrometers. By deflecting a parallel electron beam, carefully calibrated using a diffraction pattern from a known material, we can directly observe the projection-distortion in the post-specimen lenses of probe-corrected instruments, the 3-fold caustic when an image-corrector is fitted, and any misalignment of imaging detectors or spectrometer apertures...
January 8, 2018: Journal of Microscopy
https://www.readbyqxmd.com/read/29286326/role-of-rdw-in-prediction-of-burn-after-caustic-substance-ingestion
#12
Emrah Aydin, Omer Faruk Beser, Soner Sazak, Ensar Duras
A quantifiable, quick, inexpensive and reproducible predictor is needed to decide if caustic substance ingestion results in burn regardless of the symptoms. A multicenter cohort study was conducted to investigate the predictive value of red cell distribution width (RDW) in detecting the esophageal burns. The data of 174 patients were retrospectively analyzed. Eleven patients were excluded due to inability to define the substance ingested. Complete blood count (CBC) was taken at admission, and an esophagogastroduodenoscopy was performed within the first 12-24 h in all patients, regardless of their symptoms...
December 29, 2017: Children
https://www.readbyqxmd.com/read/29238173/a-light-assisted-in-situ-embedment-of-silver-nanoparticles-to-prepare-functionalized-fabrics
#13
Her Shuang Toh, Roxanne Line Faure, Liyana Bte Mohd Amin, Crystal Yu Fang Hay, Saji George
This article presents a simple, one-step, in situ generation of silver nanoparticle-functionalized fabrics with antibacterial properties, circumventing the conventional, multistep, time-consuming methods. Silver nanoparticle formation was studied with a library of capping agents (branched polyethylenimine [BPEI] of molecular weight [Mw] 10,000 and 25,000, polyvinylpyrrolidone, polyethylene glycol, polyvinylalcohol and citrate) mixed with silver nitrate. The mixture was then exposed to an assortment of light wavelengths (ultraviolet, infrared and simulated solar light) for studying the light-assisted synthesis of nanoparticles...
2017: Nanotechnology, Science and Applications
https://www.readbyqxmd.com/read/29221087/scaling-the-abruptly-autofocusing-beams-in-the-direct-space
#14
Zhenyu Zhao, Chen Xie, DanDan Ni, Yuquan Zhang, Yanfeng Li, Francois Courvoisier, Minglie Hu
We propose a simple technique to scale the abruptly autofocusing beams in the direct space by introducing a scaling factor in the phase. Analytical formulas are deduced based on optical caustics, explicitly revealing how the scaling factor controls location, peak intensity, and size of the focal spot. We demonstrate that the multiplication of a scaling factor on the phase is equivalent to the axial-scaling transformation under the paraxial approximation. Further numerical and experimental results confirm theoretical predictions...
November 27, 2017: Optics Express
https://www.readbyqxmd.com/read/29219350/generation-of-caustics-and-rogue-waves-from-nonlinear-instability
#15
Akbar Safari, Robert Fickler, Miles J Padgett, Robert W Boyd
Caustics are phenomena in which nature concentrates the energy of waves and may exhibit rogue-type behavior. Although they are known mostly in optics, caustics are intrinsic to all wave phenomena. As we demonstrate in this Letter, the formation of caustics and consequently rogue events in linear systems requires strong phase fluctuations. We show that nonlinear phase shifts can generate sharp caustics from even small fluctuations. Moreover, in that the wave amplitude increases dramatically in caustics, nonlinearity is usually inevitable...
November 17, 2017: Physical Review Letters
https://www.readbyqxmd.com/read/29216023/corticosteroids-for-preventing-caustic-esophageal-strictures-systematic-review-and-meta-analysis
#16
Raji Katibe, Ibtihal Abdelgadir, Paraic McGrogan, Anthony K Akobeng
OBJECTIVES: Caustic ingestion can have a complicated clinical course.Corticosteroids are widely used but there is uncertainty about its role in preventing esophageal stricture formation following caustic ingestion.This systematic review and meta-analysis assessed the available clinical evidence regarding the efficacy and safety of corticosteroids for preventing esophageal strictures following caustic injury. METHODS: We assessed randomized controlled trials (RCTs) that compared corticosteroids versus no corticosteroids in the prevention of esophageal stricture formation following caustic ingestion...
December 5, 2017: Journal of Pediatric Gastroenterology and Nutrition
https://www.readbyqxmd.com/read/29215277/review-of-the-scientific-understanding-of-radioactive-waste-at-the-u-s-doe-hanford-site
#17
Reid A Peterson, Edgar C Buck, Jaehun Chun, Richard C Daniel, Daniel L Herting, Eugene S Ilton, Gregg J Lumetta, Sue B Clark
This paper reviews the origin and chemical and rheological complexity of radioactive waste at the U.S. Department of Energy Hanford Site. The waste, stored in underground tanks, was generated via three distinct processes over decades of plutonium extraction operations. Although close records were kept of original waste disposition, tank-to-tank transfers and conditions that impede equilibrium complicate our understanding of the chemistry, phase composition, and rheology of the waste. Tank waste slurries comprise particles and aggregates from nano to micron scales, with varying densities, morphologies, heterogeneous compositions, and complicated responses to flow regimes and process conditions...
December 7, 2017: Environmental Science & Technology
https://www.readbyqxmd.com/read/29207003/risk-factors-for-symptomatic-esophageal-stricture-after-caustic-ingestion-a-retrospective-cohort-study
#18
P Le Naoures, A Hamy, N Lerolle, E Métivier, E Lermite, A Venara
Esophageal stricture is a major secondary complication of ingesting caustic agents. We examined our experiences with caustic injuries with a view to finding clinical and biological risk factors of esophageal strictures secondary to caustic ingestion. Records were retrieved for 58 adults admitted consecutively to our intensive care unit for caustic ingestion. Fifty cases were managed conservatively and therefore retained for analyses. Patients were grouped according to whether they developed strictures or not during the follow-up period...
June 1, 2017: Diseases of the Esophagus: Official Journal of the International Society for Diseases of the Esophagus
https://www.readbyqxmd.com/read/29201954/accuracy-of-endoscopy-in-predicting-the-depth-of-mucosal-injury-following-caustic-ingestion-a-cross-sectional-study
#19
Athena Alipour-Faz, Maryam Yousefi, Hassan Peyvandi
Introduction: Esophagogastroduodenoscopy (EGD) is currently considered as the primary method of determining the degree of mucosal injury following caustic ingestion. The present study aimed to evaluate the screening performance characteristics of EGD in predicting the depth of gastrointestinal mucosal injuries following caustic ingestion. Methods: Adult patients who were referred to emergency department due to ingestion of corrosive materials, over a 7-year period, were enrolled to this diagnostic accuracy study...
2017: Emergency (Tehran, Iran)
https://www.readbyqxmd.com/read/29195387/an-in-situ-simultaneous-measurement-system-combining-photoelasticity-and-caustics-methods-for-blast-induced-dynamic-fracture
#20
Peng Qiu, Zhongwen Yue, Shichun Zhang, Zhanfei Li
Photoelasticity and caustics methods are extensively used in the history of dynamic fracture mechanics. However, there is little work for the combination of them in the same experiment associated with high loading rate in extreme conditions. In the present work, it is the first time to build a simultaneous measurement system which can use photoelasticity and caustics methods at the same instant for in situ optical investigations of blast-induced dynamic fracture. To illustrate the capability of this system, an explosion experiment using a 2D epoxy plate is conducted, yielding consistent results between two methods...
November 2017: Review of Scientific Instruments
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