680 research outputs found
Is non-chlamydial non-gonococcal urethritis associated with significant clinical complications in men? A systematic review
© 2020 The Author(s). This article is licensed under the Creative Commons Attribution- NonCommercial-NoDerivatives 4.0 International License (CC BY- NC-ND) (http://www.karger.com/Services/OpenAccessLicense). Usage and distribution for commercial purposes as well as any dis-tribution of modified material requires written permission.Background: It is estimated that between 50 and 89% of non-gonococcal urethritis is not caused by Chlamydia trachomatis. Associations between non-chlamydial non-gonococcal urethritis (NCNGU) with balanoposthitis, epididymo-orchitis and reactive arthritis have been suggested, but evidence to support these often-theoretical relationships is sparse and further investigation is called for. Concerns over increasing antimicrobial resistance has rendered the need for clarity over this question ever more pressing in recent years. A review of the current evidence on the complications of NCNGU in men is therefore urgently warranted. Objective: This systematic review summarizes and evaluates the available evidence that NCNGU, whether symptomatic or asymptomatic, causes the significant complications that are already well-recognized to be associated with non-gonococcal urethritis. These significant complications are epididymo-orchitis, balanoposthitis, and sexually-acquired reactive arthritis (Reiter's syndrome) including arthritis or conjunctivitis. Summary: We conducted a systematic review and qualitative synthesis using the Preferred Reporting Items for Systematic Reviews and Meta-Analysis framework. Five databases (PubMed, EMBASE, Cumulative Index to Nursing and Allied Health Literature, PsycINFO, and British Nursing Index) were searched. We included studies that measured clinical outcome after diagnosis of NCNGU in men. Bias was assessed using variations of the Newcastle-Ottawa scale. Data were extracted and entered into a pre-written data abstraction proforma. Seven peer-review studies were included. This included 2 retrospective cohort studies, 1 case series, 2 case reports and 2 cross-sectional studies. The studies described and analyzed 3 types of complication: Balanitis, posthitis and/or meatitis; reactive arthritis and/or conjunctivitis; and epididymitis. All studies reported one or more complications. Key Messages: This review identifies an important avenue for future research: while the available evidence suggests that NCNGU has the potential to cause significant complications in men, with the strongest evidence existing for balanitis, posthitis and/or meatitis, the nature and significance of these relationships is far from clear. The findings of this review suggest that prospective, adequately powered research into whether there is a causal link between NCNGU and significant clinical complications in men would be highly worthwhile. The findings of this review raise important questions about the utility of the term NCNGU in research and clinical practice.Peer reviewe
Cyclotrimerisation of isocyanates catalysed by low-coordinate Mn(II) and Fe(II) m-terphenyl complexes
Two- and three-coordinate m-terphenyl complexes of manganese and iron are efficient catalysts for the selective cyclotrimerisation of primary aliphatic isocyanates affording isocyanurates in short reaction times and under mild conditions
Exciton spin relaxation in single semiconductor quantum dots
We study the relaxation of the exciton spin (longitudinal relaxation time
) in single asymmetrical quantum dots due to an interplay of the
short--range exchange interaction and acoustic phonon deformation. The
calculated relaxation rates are found to depend strongly on the dot size,
magnetic field and temperature. For typical quantum dots and temperatures below
100 K, the zero--magnetic field relaxation times are long compared to the
exciton lifetime, yet they are strongly reduced in high magnetic fields. We
discuss explicitly quantum dots based on (In,Ga)As and (Cd,Zn)Se semiconductor
compounds.Comment: accepted for Phys. Rev.
Acute Thrombogenicity of a Durable Polymer Everolimus-Eluting Stent Relative to Contemporary Drug-Eluting Stents With Biodegradable Polymer Coatings Assessed Ex Vivo in a Swine Shunt Model
AbstractObjectivesThis study sought to evaluate whether the permanent fluoropolymer-coated Xience Xpedition everolimus-eluting stent (Xience-EES) exhibits lower acute thrombogenicity compared with contemporary drug-eluting stents (DES) with biodegradable polymer coatings in an acute swine shunt model.BackgroundPrevious pre-clinical and clinical experience suggests that several factors may influence the predisposition for acute thrombus formation of polymer-coated DES, including stent design and the polymer coating technology. It remains unclear whether relevant differences exist with respect to acute thrombogenicity, particularly between current commercial stent designs using permanent polymers and those using biodegradable polymers.MethodsAn ex vivo carotid to jugular arteriovenous porcine shunt model involving a test circuit of 3 in-line stents, was used to test acute thrombogenicity, where Xience-EES (n = 24) was compared with 4 CE-marked DES with biodegradable polymer coatings (BioMatrix Flex, Synergy, Nobori, and Orsiro [n = 6 each]). After 1 h of circulation, platelet aggregation in whole mount stents was evaluated by confocal microscopy with immunofluorescent staining against dual platelet markers (CD61/CD42b) along with scanning electron microscopy.ResultsXience-EES showed the least percentage of thrombus-occupied area as compared with the biodegradable polymer-coated DES, with a significant difference compared with BioMatrix Flex and Synergy (mean differences: [BioMatrix Flex: 15.54, 95% confidence interval [CI]: 11.34 to 19.75, p < 0.001; Synergy: 8.64, 95% CI: 4.43 to 12.84, p < 0.001; Nobori: 4.22, 95% CI: -0.06 to 8.49, p = 0.055; Orsiro: 2.95, 95% CI: -1.26 to 7.15, p = 0.286). The number of cell nuclei on strut surfaces was also the least in Xience-EES, with a significant difference relative to BioMatrix Flex, Nobori, and Orsiro (mean ratios: BioMatrix Flex: 4.73, 95% CI: 2.46 to 9.08, p < 0.001; Synergy: 1.44, 95% CI: 0.75 to 2.76, p = 0.51; Nobori: 5.97, 95% CI: 3.11 to 11.44, p < 0.001; Orsiro: 5.16, 95% CI: 2.69 to 9.91, p < 0.001).ConclusionsXience-EES’s overall design confers acute thromboresistance relative to contemporary DES with biodegradable coatings, with less platelet aggregation versus BioMatrix Flex and Synergy, and less inflammatory cell attachment versus BioMatrix Flex, Nobori, and Orsiro, in an ex vivo swine shunt model, which lends support to reported clinical findings of lower early stent thrombosis
HYPER-RESPONSIVENESS OF ALDOSTERONE TO METOCLOPRAMIDE IN ALDOSTERONISM
Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/73101/1/j.1365-2265.1982.tb02761.x.pd
Comparison of structural transformations and superconductivity in compressed Sulfur and Selenium
Density-functional calculations are presented for high-pressure structural
phases of S and Se. The structural phase diagrams, phonon spectra,
electron-phonon coupling, and superconducting properties of the isovalent
elements are compared. We find that with increasing pressure, Se adopts a
sequence of ever more closely packed structures (beta-Po, bcc, fcc), while S
favors more open structures (beta-Po, simple cubic, bcc). These differences are
shown to be attributable to differences in the S and Se core states. All the
compressed phases of S and Se considered are calculated to have weak to
moderate electron-phonon coupling strengths consistent with superconducting
transition temperatures in the range of 1 to 20 K. Our results compare well
with experimental data on the beta-Po --> bcc transition pressure in Se and on
the superconducting transition temperature in beta-Po S. Further experiments
are suggested to search for the other structural phases predicted at higher
pressures and to test theoretical results on the electron-phonon interaction
and superconducting properties
On some algebraic identities and the exterior product of double forms
We use the exterior product of double forms to reformulate celebrated
classical results of linear algebra about matrices and bilinear forms namely
the Cayley-Hamilton theorem, Laplace expansion of the determinant, Newton
identities and Jacobi's formula for the determinant. This new formalism is then
used to naturally generalize the previous results to higher multilinear forms
namely to double forms.
In particular, we show that the Cayley-Hamilton theorem once applied to the
second fundamental form of a hypersurface of the Euclidean space is equivalent
to a linearized version of the Gauss-Bonnet theorem, and once its
generalization is applied to the Riemann curvature tensor (seen as a
double form) is an infinitisimal version of the general Gauss-Bonnet-Chern
theorem. In addition to that, the general Cayley-Hamilton theorems generate
several universal curvature identities. The generalization of the classical
Laplace expansion of the determinant to double forms is shown to lead to new
general Avez type formulas for all Gauss-Bonnet curvatures.Comment: 32 pages, in this new version we added: an introduction to the
exterior and composition products of double forms, a new section about
hyperdeterminants and hyperpfaffians and reference
On post-Lie algebras, Lie--Butcher series and moving frames
Pre-Lie (or Vinberg) algebras arise from flat and torsion-free connections on
differential manifolds. They have been studied extensively in recent years,
both from algebraic operadic points of view and through numerous applications
in numerical analysis, control theory, stochastic differential equations and
renormalization. Butcher series are formal power series founded on pre-Lie
algebras, used in numerical analysis to study geometric properties of flows on
euclidean spaces. Motivated by the analysis of flows on manifolds and
homogeneous spaces, we investigate algebras arising from flat connections with
constant torsion, leading to the definition of post-Lie algebras, a
generalization of pre-Lie algebras. Whereas pre-Lie algebras are intimately
associated with euclidean geometry, post-Lie algebras occur naturally in the
differential geometry of homogeneous spaces, and are also closely related to
Cartan's method of moving frames. Lie--Butcher series combine Butcher series
with Lie series and are used to analyze flows on manifolds. In this paper we
show that Lie--Butcher series are founded on post-Lie algebras. The functorial
relations between post-Lie algebras and their enveloping algebras, called
D-algebras, are explored. Furthermore, we develop new formulas for computations
in free post-Lie algebras and D-algebras, based on recursions in a magma, and
we show that Lie--Butcher series are related to invariants of curves described
by moving frames.Comment: added discussion of post-Lie algebroid
Scaling violations: Connections between elastic and inelastic hadron scattering in a geometrical approach
Starting from a short range expansion of the inelastic overlap function,
capable of describing quite well the elastic pp and scattering data,
we obtain extensions to the inelastic channel, through unitarity and an impact
parameter approach. Based on geometrical arguments we infer some
characteristics of the elementary hadronic process and this allows an excellent
description of the inclusive multiplicity distributions in and
collisions. With this approach we quantitatively correlate the violations of
both geometrical and KNO scaling in an analytical way. The physical picture
from both channels is that the geometrical evolution of the hadronic
constituents is principally reponsible for the energy dependence of the
physical quantities rather than the dynamical (elementary) interaction itself.Comment: 16 pages, aps-revtex, 11 figure
High Precision Mass Measurements in and Families Revisited
High precision mass measurements in and families performed
in 1980-1984 at the VEPP-4 collider with OLYA and MD-1 detectors are revisited.
The corrections for the new value of the electron mass are presented. The
effect of the updated radiative corrections has been calculated for the
and mass measurements.Comment: 5 pages, 1 table, submitted to Phys. Lett.
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