440 research outputs found
Junior Recital: Jason Kaplan, saxophone
This recital is presented in partial fulfillment of requirements for the degree Bachelor of Music in Performance. Mr. Kaplan studies saxophone with Sam Skelton.https://digitalcommons.kennesaw.edu/musicprograms/1497/thumbnail.jp
Viable pathogen aerosols produced during laser dermatology surgery - a quantified analysis
The use of laser processes for surgical, medical and cosmetic procedures has been increasing with five hundred thousand workers exposed to laser surgical smoke per year. The use of lasers introduces direct beam hazards into the environment but also generates unique hazards such as material ejected from the laser process. Within this material can be potentially harmful particulate when inhaled by humans, accompanying this particulate is a foul unwanted odour. Along with the generation of these particles it is extremely possible for viable biological organisms to be generated with the particulate. Airborne particulate matter or bio-aerosols are not just a hazard to the patient, but also to other people in the environment around the laser process. The aim of this paper is to investigate and quantify the aerosol danger to both patients and operators when utilising lasers within surgical procedures, while suggesting a suitable initial solution. The tailored research for this aim will focus on whether a suitable extraction system can be developed and the effects that
different types of lasers have on the size and visuals of any particulate generated. To determine whether there is a risk of infection and to ascertain the level of infection control, the possibility of viable bio-aerosols being detected after a laser process should be considered. The experiments are split into 3 sections; section 1 is the testing of the extraction system using a smoke generation system to ascertain visual proof of a functioning extraction system, section 2 is the testing of
the effect of laser irradiance on the tissue simulant to determine the effect of varying laser types on the particulate generated and section 3 is the generation and measurement of bio-aerosols with the use of bio markers to test for survival of laser processing and transmission
The design of medical laser surgery dermatology handpieces for radiation control and direct extraction of infectious laser generated plume
Surgical skin treatments such as; laser ablation, laser scalpels, hair removal, tattooed removal etc can all generate direct and secondary optical radiation hazards, however, because they are designed to intentionally destroy human tissue, they also generate gaseous and particulate emissions. This second family often referred to as; surgical smoke, surgical smoke plume and surgical fume, have now been identified as producing viable bio-active aerosols, these by-products now pose infectious hazards to the patient and staff of the operating room. Local extraction is sometimes used to try and reduce the airborne concentration of these byproducts though in virtually all cases the smell of the process is detectable by all. The optical radiation hazard usually dictates the wearing of protective eyewear to provide some level of personal protection. A major health concern to all medical and cosmetic facilities is that of infection control. Surgical smoke is usually
overlooked as a source of infection within the operating environment and it has been known since the mid-1980s that the particulate can carry with it live pathogens from the patient which can now be in skin contact or respired by the operating staff. A paper presented by the authors in the Medical Session here at ILSC provides possibly the first quantitative analysis of the hazards the surgeon and other staff are subject to. This paper examines the practical limitations of the existing approaches and provides some simple practical control measures that provide complete radiation containment as well as enable complete particulate and gas extraction without any reliance on any form of personal protection for the patient and operating staff. These designs have now been tested and are shown to offer 100% effective plume extraction and radiation containment
Figuring Out Gas & Galaxies in Enzo (FOGGIE). II. Emission from the z=3 Circumgalactic Medium
Observing the circumgalactic medium (CGM) in emission provides 3D maps of the
spatial and kinematic extent of the gas that fuels galaxies and receives their
feedback. We present mock emission-line maps of highly resolved CGM gas from
the FOGGIE project (Figuring Out Gas & Galaxies in Enzo) and link these maps
back to physical and spatial properties of the gas. By increasing the spatial
resolution alone, the total luminosity of the line emission increases by an
order of magnitude. This increase arises in the abundance of dense small-scale
structure resolved when the CGM gas is simulated to < 100 pc scales. Current
integral field unit instruments like KCWI and MUSE should be able to detect the
brightest knots and filaments of such emission, and from this to infer the bulk
kinematics of the CGM gas with respect to the galaxy. We conclude that
accounting for small-scale structure well below the level of instrument spatial
resolution is necessary to properly interpret such observations in terms of the
underlying gas structure driving observable emission.Comment: 18 pages, 10 figures. Submitted to ApJ. Comments welcom
Figuring Out Gas & Galaxies In Enzo (FOGGIE) V: The Virial Temperature Does Not Describe Gas in a Virialized Galaxy Halo
The classical definition of the virial temperature of a galaxy halo excludes
a fundamental contribution to the energy partition of the halo: the kinetic
energy of non-thermal gas motions. Using simulations of low-redshift, galaxies from the FOGGIE project (Figuring Out Gas & Galaxies In Enzo)
that are optimized to resolve low-density gas, we show that the kinetic energy
of non-thermal motions is roughly equal to the energy of thermal motions. The
simulated FOGGIE halos have lower bulk temperatures than
expected from a classical virial equilibrium, owing to significant non-thermal
kinetic energy that is formally excluded from the definition of
. We derive a modified virial temperature explicitly including
non-thermal gas motions that provides a more accurate description of gas
temperatures for simulated halos in virial equilibrium. Strong bursts of
stellar feedback drive the simulated FOGGIE halos out of virial equilibrium,
but the halo gas cannot be accurately described by the standard virial
temperature even when in virial equilibrium. Compared to the standard virial
temperature, the cooler modified virial temperature implies other effects on
halo gas: (i) the thermal gas pressure is lower, (ii) radiative cooling is more
efficient, (iii) O VI absorbing gas that traces the virial temperature may be
prevalent in halos of a higher mass than expected, (iv) gas mass estimates from
X-ray surface brightness profiles may be incorrect, and (v) turbulent motions
make an important contribution to the energy balance of a galaxy halo.Comment: 30 pages, 14 figures, accepted to Ap
Figuring Out Gas & Galaxies in Enzo (FOGGIE). III. The Mocky Way:Investigating Biases in Observing the Milky Way's Circumgalactic Medium
The circumgalactic medium (CGM) of the Milky Way is mostly obscured by nearby
gas in position-velocity space because we reside inside the Galaxy. Substantial
biases exist in most studies on the Milky Way's CGM that focus on
easier-to-detect high-velocity gas. With mock observations on a Milky-Way
analog from the FOGGIE simulation, we investigate four observational biases
related to the Milky Way's CGM. First, QSO absorption-line studies probe a
limited amount of the CGM mass: only 35% of the mass is at high Galactic
latitudes degrees, of which only half is moving at km s. Second, the inflow rate () of the cold
gas observable in HI 21cm is reduced by a factor of as we switch from
the local standard of rest to the galaxy's rest frame; meanwhile of
the cool and warm gas does not change significantly. Third, OVI and NV are
promising ions to probe the Milky Way's outer CGM (15 kpc), but CIV
may be less sensitive. Lastly, the scatter in ion column density is a factor of
2 higher if the CGM is observed from inside-out than from external views
because of the gas radial density profile. Our work highlights that
observations of the Milky Way's CGM, especially those using HI 21cm and QSO
absorption lines, are highly biased. We demonstrate that these biases can be
quantified and calibrated through synthetic observations with simulated
Milky-Way analogs.Comment: ApJ in pres
The Truth Comes From Us: Supporting Workers with Developmental Disabilities
Employment professionals play a powerful role in the pursuit of true inclusion. This paper by self-advocates outlines key steps on how allies can move people with developmental disabilities out of poverty and into the heart of our communities
Figuring Out Gas & Galaxies In Enzo (FOGGIE). IV. The Stochasticity of Ram Pressure Stripping in Galactic Halos
We study ram pressure stripping in simulated Milky Way-like halos at z>=2
from the Figuring Out Gas & Galaxies In Enzo (FOGGIE) project. These
simulations reach exquisite resolution in their circumgalactic medium (CGM) gas
owing to FOGGIE's novel refinement scheme. The CGM of each halo spans a wide
dynamic range in density and velocity over its volume---roughly 6 dex and 1000
km/s, respectively---translating into a 5 dex range in ram pressure imparted to
interacting satellites. The ram pressure profiles of the simulated CGM are
highly stochastic, owing to kpc-scale variations of the density and velocity
fields of the CGM gas. As a result, the efficacy of ram pressure stripping
depends strongly on the specific path a satellite takes through the CGM. The
ram-pressure history of a single satellite is generally unpredictable and not
well correlated with its approach vector with respect to the host galaxy. The
cumulative impact of ram pressure on the simulated satellites is dominated by
only a few short strong impulses---on average, 90% of the total surface
momentum gained through ram pressure is imparted in 20% or less of the total
orbital time. These results reveal an erratic mode of ram pressure stripping in
Milky-Way like halos at high redshift---one that is not captured by a smooth
spherically-averaged model of the circumgalactic medium.Comment: 18 pages, 10 figures. Submitted to Ap
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