2,898 research outputs found
An Apparatus for the Study of the Kinetics of Thermal Decompositions
For kinetic studies accurate control of the temperature of the reaction flask is required. The reaction flask was placed in a furnace which was constructed in a large metal container A. Forty-four turns of #22 nichrome wire were wound about a 12 x4½ refractory cement core. To insure uniform distribution of heat, the flask was immersed in a bath of molten tin
Relations between fusion cross sections and average angular momenta
We study the relations between moments of fusion cross sections and averages
of angular momentum. The role of the centrifugal barrier and the target
deformation in determining the effective barrier radius are clarified. A simple
method for extracting average angular momentum from fusion cross sections is
demonstrated using numerical examples as well as actual data.Comment: 16 REVTeX pages plus 8 included Postscript figures (uses the epsf
macro); submitted to Phys. Rev. C; also available at
http://nucth.physics.wisc.edu/preprint
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Injection Drug Use and Infectious Disease Practice: A National Provider Survey
Abstract Background: The opioid epidemic has swept across the U.S. at a staggering rate, with an estimated half million to one million persons injecting drugs annually. Rates of hospitalization for injection drug use (IDU)-related infection have risen precipitously, comprising an escalating proportion of infectious diseases provider volume in highly impacted regions. Methods: In March 2017, the Emerging Infections Network surveyed their national network of infectious diseases (ID) physicians to evaluate perspectives relating to the care of persons who inject drugs (PWID), including the frequency of, and management strategies for, IDU-related infection, the availability of addiction services, and the evolving role of ID physicians in the management of addiction. Results: Over half (53%; N = 672) of 1,276 members with an adult ID practice participated; 78% (n = 526) reported treating PWID. Of 526 respondents, 464 (88%) reported seeing ≥1 patient per month with an IDU-related infection; 228 (43%) reported ≥6 per month. In the past year, 79% of respondents reported the majority of IDU-related infections seen required ≥2 weeks of parenteral therapy and reported frequently encountering skin and soft-tissue infections (61%), bacteremia/fungemia (53%), and endocarditis (50%). Strategies most commonly employed for management of prolonged parenteral antibiotic therapy included: completion of entire course on inpatient unit (by 41%) and transfer to supervised facility for completion (35%). Only 35% of respondents agree/strongly agree their health system offers comprehensive treatment of substance use disorders (N = 181). Though nearly half of respondents felt that ID providers should actively manage substance use disorders (46%; N = 241), only 3% reported being waivered to prescribe buprenorphine for treatment of opioid use disorder. Conclusion: The majority of infectious diseases physicians frequently care for PWID with serious infections. There is significant diversity amongst providers with regards to the availability of comprehensive addiction services as well as perceptions regarding the role providers should play in the management of addiction. Guidelines for the management of serious infections and concurrent addiction in the midst of the escalating national opioid crisis should be considered. Disclosures All authors: No reported disclosures
Effects of finite width of excited states on heavy-ion sub-barrier fusion reactions
We discuss the effects of coupling of the relative motion to nuclear
collective excitations which have a finite lifetime on heavy-ion fusion
reactions at energies near and below the Coulomb barrier. Both spreading and
escape widths are explicitly taken into account in the exit doorway model. The
coupled-channels equations are numerically solved to show that the finite
resonance width always hinders fusion cross sections at subbarrier energies
irrespective of the relative importance between the spreading and the escape
widths. We also show that the structure of fusion barrier distribution is
smeared due to the spreading of the strength of the doorway state.Comment: 13 pages, 3 figures, Submitted to Physical Review
SU(16) grandunification: breaking scales, proton decay and neutrino magnetic moment
We give a detailed renormalization group analysis for the SU(16) grandunified
group with general breaking chains in which quarks and leptons transform
separately at intermediate energies. Our analysis includes the effects of Higgs
bosons. We show that the grandunification scale could be as low as GeV and give examples where new physics could exist at relatively low
energy ( GeV). We consider proton decay in this model and show that
it is consistent with a low grandunification scale. We also discuss the
possible generation of a neutrino magnetic moment in the range of to
with a very small mass by the breaking of the embedded
SU(2) symmetry at a low energy.Comment: (16 pages in REVTEX + 6 figures not included) OITS-49
Gattini 2010: Cutting Edge Science at the Bottom of the World
The high altitude Antarctic sites of Dome A and the South Pole offer intriguing locations for future large scale optical astronomical
Observatories. The Gattini project was created to measure the optical
sky brightness, large area cloud cover and aurora of the winter-time
sky above such high altitude Antarctic sites. The Gattini-DomeA camera
was installed on the PLATO instrument module as part of the Chinese-led
traverse to the highest point on the Antarctic plateau in January 2008.
This single automated wide field camera contains a suite of Bessel
photometric filters (B, V, R) and a long-pass red filter for the
detection and monitoring of OH emission. We have in hand one complete
winter-time dataset (2009) from the camera that was recently returned
in April 2010.
The Gattini-South Pole UV camera is a wide-field optical camera that in
2011 will measure for the first time the UV properties of the
winter-time sky above the South Pole dark sector. This unique dataset
will consist of frequent images taken in both broadband U and B filters
in addition to high resolution (R similar to 5000) long slit
spectroscopy over a narrow bandwidth of the central field. The camera
is a proof of concept for the 2m-class Antarctic Cosmic Web Imager
telescope, a dedicated experiment to directly detect and map the
redshifted lyman alpha fluorescence or Cosmic Web emission we believe
possible due to the unique geographical qualities of the site.
We present the current status of both projects
Enhancing cell and gene therapy manufacture through the application of advanced fluorescent optical sensors (Review)
Cell and gene therapies (CGTs) are examples of future therapeutics that can be used to cure or alleviate the symptoms of disease, by repairing damaged tissue or reprogramming defective genetic information. However, despite the recent advancements in clinical trial outcomes, the path to widescale adoption of CGTs remains challenging, such that the emergence of a “blockbuster” therapy has so far proved elusive. Manufacturing solutions for these therapies require the application of scalable and replicable cell manufacturing techniques, which differ markedly from the existing pharmaceutical incumbent. Attempts to adopt this pharmaceutical model for CGT manufacture have largely proved unsuccessful. The most significant challenges facing CGT manufacturing are process analytical testing and quality control. These procedures would greatly benefit from improved sensory technologies that allow direct measurement of critical quality attributes, such as pH, oxygen, lactate and glucose. In turn, this would make manufacturing more robust, replicable and standardized. In this review, the present-day state and prospects of CGT manufacturing are discussed. In particular, the authors highlight the role of fluorescent optical sensors, focusing on their strengths and weaknesses, for CGT manufacture. The review concludes by discussing how the integration of CGT manufacture and fluorescent optical sensors could augment future bioprocessing approaches
A corresponding states approach to Small-Angle-Scattering for polydisperse ionic colloidal fluids
Approximate scattering functions for polydisperse ionic colloidal fluids are
obtained by a corresponding states approach. This assumes that all pair
correlation functions of a polydisperse fluid are
conformal to those of an appropriate monodisperse binary fluid (reference
system) and can be generated from them by scaling transformations. The
correspondence law extends to ionic fluids a {\it scaling approximation} (SA)
successfully proposed for nonionic colloids in a recent paper. For the
primitive model of charged hard spheres in a continuum solvent, the partial
structure factors of the monodisperse binary reference system are evaluated by
solving the Orstein-Zernike (OZ) integral equations coupled with an approximate
closure. The SA is first tested within the mean spherical approximation (MSA)
closure, which allows analytical solutions. The results are found in good
overall agreement with exact MSA predictions up to relevant polidispersity. The
SA is shown to be an improvement over the ``decoupling approximation'' extended
to the ionic case. The simplicity of the SA scheme allows its application also
when the OZ equations can be solved only numerically. An example is then given
by using the hypernetted chain (HNC) closure. Shortcomings of the SA approach,
its possible use in the analysis of experimental scattering data and other
related points are also briefly addressed.Comment: 29 pages, 7 postscript figures (included), Latex 3.0, uses aps.sty,
to appear in Phys. Rev. E (1999
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