QuickCut Waterjet Cutter

The QuickCut Waterjet Cutter was created in 2019 as a senior design project. This is the third iteration of the waterjet cutter. The goal of this project was to create an operable CNC waterjet cutter that is able to cut 1/16” tensile specimens consisting of nonferrous metal or plastic. This machine will be utilized in the Manufacturing Laboratory at the University of Akron to provide education to interested students on the waterjet cutting process, how it operates, and industrial application of the technology. Waterjet cutting is a subtractive manufacturing process which is recognized for its specialized applications such as cutting dangerous materials or preserving heat treatment. Waterjet cutting utilizes high pressurized water with entrained garnet to cut through materials with precision and accuracy. The QuickCut Waterjet Cutter aims to bring the applications of industrial waterjet cutting operations to the smaller, tabletop scale to cut softer materials with precision. This report goes in depth on what defines an abrasive waterjet cutter, important components and the benefits of the waterjet cutting process. Detailed steps on how the newest rendition of the Quickcut Waterjet Cutter was created are covered. This includes brainstorming, design of components, design of controls, manufacturing process, as well as testing and future work to be completed

High Energy Photon-Photon Collisions -

The collisions of high energy photons produced at an electron-positron collider provide a comprehensive laboratory for testing QCD, electroweak interactions, and extensions of the Standard Model. The luminosity and energy of the colliding photons produced by back-scattering laser beams is expected to be comparable to that of the primary $e^+e^-$ collisions. In this overview, we shall focus on tests of electroweak theory in photon-photon annihilation, particularly $\gamma\gamma \rightarrow W^+ W^-$, $\gamma\gamma \rightarrow$ Higgs bosons, and higher-order loop processes, such as $\gamma\gamma \rightarrow \gamma\gamma, Z \gamma$ and $ZZ.$ Since each photon can be resolved into a $W^+ W^-$ pair, high energy photon-photon collisions can also provide a remarkably background-free laboratory for studying $WW$ collisions and annihilation. We also review high energy $\gamma\gamma$ tests of quantum chromodynamics, such as the scaling of the photon structure function, $t \bar t$ production, mini-jet processes, and diffractive reactions.Comment: uses PHYZZX, 52 pages, 30 figures (available upon request), SLAC-PUB-657

An Observational Study of Dyspnea in Emergency Departments: The Asia, Australia, and New Zealand Dyspnea in Emergency Departments Study ( AANZDEM )

International audienceObjectives: The objective was to describe the epidemiology of dyspnea presenting to emergency departments (EDs) in the Asia-Pacific region, to understand how it is investigated and treated and its outcome.Methods: Prospective interrupted time series cohort study conducted at three time points in EDs in Australia, New Zealand, Singapore, Hong Kong, and Malaysia of adult patients presenting to the ED with dyspnea as a main symptom. Data were collected over three 72-hour periods and included demographics, comorbidities, mode of arrival, usual medications, prehospital treatment, initial assessment, ED investigations, treatment in the ED, ED diagnosis, disposition from ED, in-hospital outcome, and final hospital diagnosis. The primary outcomes of interest are the epidemiology, investigation, treatment, and outcome of patients presenting to ED with dyspnea.Results: A total of 3,044 patients were studied. Patients with dyspnea made up 5.2% (3,105/60,059, 95% confidence interval [CI] = 5.0% to 5.4%) of ED presentations, 11.4% of ward admissions (1,956/17,184, 95% CI = 10.9% to 11.9%), and 19.9% of intensive care unit (ICU) admissions (104/523, 95% CI = 16.7% to 23.5%). The most common diagnoses were lower respiratory tract infection (20.2%), heart failure (14.9%), chronic obstructive pulmonary disease (13.6%), and asthma (12.7%). Hospital ward admission was required for 64% of patients (95% CI = 62% to 66%) with 3.3% (95% CI = 2.8% to 4.1%) requiring ICU admission. In-hospital mortality was 6% (95% CI = 5.0% to 7.2%).Conclusion: Dyspnea is a common symptom in ED patients contributing substantially to ED, hospital, and ICU workload. It is also associated with significant mortality. There are a wide variety of causes however chronic disease accounts for a large proportion