412 research outputs found
Testicular trauma resulting in shock and systemic inflammatory response syndrome: a case report
INTRODUCTION:Acute painful scrotum in children may be associated with torsion of the testis, hematocele, epididymitis and direct testicular injury with hematoma formation. More frequently, however, acute scrotum occurs without a precipitating factor. While most traumatic testicular injuries resolve with conservative management, many require surgical exploration and some are life-threatening.CASE PRESENTATION:A 13-year-old boy with a history of testicular trauma presented with severe scrotal swelling and shock. This case study examines the presentation and possible role of cytokines in the development of systemic inflammatory response syndrome in a child with acute traumatic epididymitis.CONCLUSION:Post-traumatic epididymitis presenting as shock in boys is rarely reported. We advocate early recognition of the chain of events leading to clinical presentation of shock and prompt treatment to preserve testicular viability
First-principles calculation of intrinsic defect formation volumes in silicon
We present an extensive first-principles study of the pressure dependence of
the formation enthalpies of all the know vacancy and self-interstitial
configurations in silicon, in each charge state from -2 through +2. The neutral
vacancy is found to have a formation volume that varies markedly with pressure,
leading to a remarkably large negative value (-0.68 atomic volumes) for the
zero-pressure formation volume of a Frenkel pair (V + I). The interaction of
volume and charge was examined, leading to pressure--Fermi level stability
diagrams of the defects. Finally, we quantify the anisotropic nature of the
lattice relaxation around the neutral defects.Comment: 9 pages, 9 figure
Monte Carlo with Absorbing Markov Chains: Fast Local Algorithms for Slow Dynamics
A class of Monte Carlo algorithms which incorporate absorbing Markov chains
is presented. In a particular limit, the lowest-order of these algorithms
reduces to the -fold way algorithm. These algorithms are applied to study
the escape from the metastable state in the two-dimensional square-lattice
nearest-neighbor Ising ferromagnet in an unfavorable applied field, and the
agreement with theoretical predictions is very good. It is demonstrated that
the higher-order algorithms can be many orders of magnitude faster than either
the traditional Monte Carlo or -fold way algorithms.Comment: ReVTeX, Request 3 figures from [email protected]
Balancing influence between actors in healthcare decision making
<p>Abstract</p> <p>Background</p> <p>Healthcare costs in most developed countries are not clearly linked to better patient and public health outcomes, but are rather associated with service delivery orientation. In the U.S. this has resulted in large variation in healthcare availability and use, increased cost, reduced employer participation in health insurance programs, and reduced overall population health outcomes. Recent U.S. healthcare reform legislation addresses only some of these issues. Other countries face similar healthcare issues.</p> <p>Discussion</p> <p>A major goal of healthcare is to enhance patient health outcomes. This objective is not realized in many countries because incentives and structures are currently not aligned for maximizing population health. The misalignment occurs because of the competing interests between "actors" in healthcare. In a simplified model these are individuals motivated to enhance their own health; enterprises (including a mix of nonprofit, for profit and government providers, payers, and suppliers, etc.) motivated by profit, political, organizational and other forces; and government which often acts in the conflicting roles of a healthcare payer and provider in addition to its role as the representative and protector of the people. An imbalance exists between the actors, due to the resources and information control of the enterprise and government actors relative to the individual and the public. Failure to use effective preventive interventions is perhaps the best example of the misalignment of incentives. We consider the current Pareto efficient balance between the actors in relation to the Pareto frontier, and show that a significant change in the healthcare market requires major changes in the utilities of the enterprise and government actors.</p> <p>Summary</p> <p>A variety of actions are necessary for maximizing population health within the constraints of available resources and the current balance between the actors. These actions include improved transparency of all aspects of medical decision making, greater involvement of patients in shared medical decision making, greater oversight of guideline development and coverage decisions, limitations on direct to consumer advertising, and the need for an enhanced role of the government as the public advocate.</p
Primary decomposition and the fractal nature of knot concordance
For each sequence of polynomials, P=(p_1(t),p_2(t),...), we define a
characteristic series of groups, called the derived series localized at P.
Given a knot K in S^3, such a sequence of polynomials arises naturally as the
orders of certain submodules of the sequence of higher-order Alexander modules
of K. These group series yield new filtrations of the knot concordance group
that refine the (n)-solvable filtration of Cochran-Orr-Teichner. We show that
the quotients of successive terms of these refined filtrations have infinite
rank. These results also suggest higher-order analogues of the p(t)-primary
decomposition of the algebraic concordance group. We use these techniques to
give evidence that the set of smooth concordance classes of knots is a fractal
set. We also show that no Cochran-Orr-Teichner knot is concordant to any
Cochran-Harvey-Leidy knot.Comment: 60 pages, added 4 pages to introduction, minor corrections otherwise;
Math. Annalen 201
New distinguished classes of spectral spaces: a survey
In the present survey paper, we present several new classes of Hochster's
spectral spaces "occurring in nature", actually in multiplicative ideal theory,
and not linked to or realized in an explicit way by prime spectra of rings. The
general setting is the space of the semistar operations (of finite type),
endowed with a Zariski-like topology, which turns out to be a natural
topological extension of the space of the overrings of an integral domain,
endowed with a topology introduced by Zariski. One of the key tool is a recent
characterization of spectral spaces, based on the ultrafilter topology, given
in a paper by C. Finocchiaro in Comm. Algebra 2014. Several applications are
also discussed
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