Topical antihistamines and mast cell stabilisers for treating seasonal and perennial allergic conjunctivitis

Peer reviewedPublisher PD

Human response to vibration in residential environments, technical report 1 : measurement of vibration exposure

The Technical Report 1 describes the research undertaken to develop a method by which human exposure to vibration in residential environments can be assessed. That work has been carried out by the University of Salford supported by the Department of environment food and rural affairs (Defra). The overall aim of the project is to derive exposure-response relationships for human vibration in residential environments. This document in particular focuses on the equipment and methodology employed to measure vibration from different sources. The main objective of this report is to describe the practical experience of implementing a vibration measurement protocol. Reported here are findings obtained in the field measurements and a description of a feasible method for measuring vibration for different sources. In addition, controlled tests performed to determine the suitability of the vibration mounting for various practical situations are reported

On the Quantum Mechanics for One Photon

This paper revisits the quantum mechanics for one photon from the modern viewpoint and by the geometrical method. Especially, besides the ordinary (rectangular) momentum representation, we provide an explicit derivation for the other two important representations, called the cylindrically symmetrical representation and the spherically symmetrical representation, respectively. These other two representations are relevant to some current photon experiments in quantum optics. In addition, the latter is useful for us to extract the information on the quantized black holes. The framework and approach presented here are also applicable to other particles with arbitrary mass and spin, such as the particle with spin 1/2.Comment: 15 pages, typos corrected, references added, corrections and improvements made owing to the anonymous referee's responsible and helpful remarks, accepted for publication in Journal of Mathematical Physics:

Search for direct production of charginos, neutralinos and sleptons in final states with two leptons and missing transverse momentum in pp collisions at √s = 8TeV with the ATLAS detector

Searches for the electroweak production of charginos, neutralinos and sleptons in final states characterized by the presence of two leptons (electrons and muons) and missing transverse momentum are performed using 20.3 fb−1 of proton-proton collision data at s√ = 8 TeV recorded with the ATLAS experiment at the Large Hadron Collider. No significant excess beyond Standard Model expectations is observed. Limits are set on the masses of the lightest chargino, next-to-lightest neutralino and sleptons for different lightest-neutralino mass hypotheses in simplified models. Results are also interpreted in various scenarios of the phenomenological Minimal Supersymmetric Standard Model

Quantifying the pathways of latent heat dissipation during droplet freezing on cooled substrates

When a liquid droplet freezes on a cooled substrate, the portion of latent heat released by ice formation that is not immediately absorbed by the supercooled liquid droplet is transferred to the solid substrate below the droplet and the surrounding air. It is important to quantify heat dissipation through these two pathways because they govern the propagation of frost between multiple droplets. In this paper, infrared (IR) thermography measurements of the surface of a freezing droplet are used to quantify the fraction of latent heat released to the substrate and the ambient air. These IR measurements also show that the crystallization dynamics are related to the size of the droplet, as the freezing front moves slower in larger droplets. Numerical simulations of the solidification process are performed using the IR temperature data at the contact line of the droplet as a boundary condition. These simulations, which have good agreement with experimentally measured freezing times, reveal that the heat transferred to the substrate through the base contact area of the droplet is best described by a time-dependent temperature boundary condition, contrary to the constant values of base temperature and rates of heat transfer assumed in previous numerical simulations reported in the literature. In further contrast to the highly simplified descriptions of the interaction between a droplet and its surrounding used in previous models, the model developed in the current work accounts for heat conduction, convection, and evaporative cooling at the droplet-air interface. The simulation results indicate that only a small fraction of heat is lost through the droplet-air interface via conduction and evaporative cooling. The heat transfer rate to the substrate of the droplet is shown to be at least one order of magnitude greater than the heat transferred to the ambient air

Asymmetric Solidification During Droplet Freezing in the Presence of a Neighboring Droplet

A supercooled liquid droplet that freezes on a cold substrate interacts with the local surroundings through heat and mass exchange. Heat loss occurs to the substrate via conduction and at the droplet interface via evaporative cooling, diffusion, and convection. In a group of many droplets, these interac- tions are believed to be responsible for inter-droplet frost propagation and the evaporation of supercooled neighboring droplets. Furthermore, interactions between a standalone freezing droplet and its surround- ings can lead to the formation of condensation halos and asymmetric solidification induced by exter- nal flows. This paper investigates droplet-to-droplet interactions via heat and mass exchange between a freezing droplet and a neighboring droplet, for which asymmetries are observed in the final shape of the frozen droplet. Side-view infrared (IR) thermography measurements of the surface temperature for a pair of freezing droplets, along with three-dimensional numerical simulations of the solidification process, are used to quantify the intensity and nature of these interactions. Two droplet-to-droplet interaction mech- anisms causing asymmetric freezing are identified: (1) non-uniform evaporative cooling on the surface of the freezing droplet caused by vapor starvation in the air between the droplets; and (2) a non-uniform thermal resistance at the contact area of the freezing droplet caused by the heat conduction within the neighboring droplet. The combined experimental and numerical results show that the size of the freez- ing droplet relative to its neighbor can significantly impact the intensity of the interaction between the droplets and, therefore, the degree of asymmetry. A small droplet freezing in the presence of a large droplet, which blocks vapor from freely diffusing to the surface of the small droplet, causes substan- tial asymmetry in the solidification process. The droplet-to-droplet interactions investigated in this paper provide insights into the role of latent heat dissipation during condensation frosting

Análisis de opciones para la excavación de la casa de máquinas del Proyecto Hidroeléctrico Pirrís.

Proyecto de Graduación (Licenciatura en Ingeniería en Construcción) Instituto Tecnológico de Costa Rica, Escuela de Ingeniería en Construcción, 2002.La excavación masiva representa siempre un gran reto para el profesional a cargo de la misma, muchos detalles deben ser tomados en cuenta para poder definir el proceso constructivo más conveniente. Es en ese punto donde la experiencia es fundamental, así como una buena referencia. Para la excavación de la Casa de Máquinas del Proyecto Hidroeléctrico Pirrís se cuenta con tres opciones previamente diseñadas; una alternativa con un volumen de 440.889 m3 a base de bermas y taludes estabilizados con concreto lanzado y pernos de anclaje, una segunda opción igualmente con taludes y bermas, pero que además incluye una pantalla de pilotes en el perímetro de lo que será el edificio, y la tercera opción que consiste en la excavación mediante un pozo profundo. Para cada una de ellas se presenta una descripción del proceso constructivo, la programación, asignación de recursos y presupuesto incluyendo personal, materiales, equipo y maquinaria necesarios para su ejecución. De esta forma se obtiene para cada una, un costo y duración que permiten compararlos entre sí para poder concluir que la tercera opción es la más viable, con un costo de $1.754.501 y una duración de 249 días, un volumen de excavación de 320.245 m3 y el tener una buena disponibilidad de recursos y la alta confiabilidad del sistema