100 research outputs found
Equations over free inverse monoids with idempotent variables
We introduce the notion of idempotent variables for studying equations in
inverse monoids.
It is proved that it is decidable in singly exponential time (DEXPTIME)
whether a system of equations in idempotent variables over a free inverse
monoid has a solution. The result is proved by a direct reduction to solve
language equations with one-sided concatenation and a known complexity result
by Baader and Narendran: Unification of concept terms in description logics,
2001. We also show that the problem becomes DEXPTIME hard , as soon as the
quotient group of the free inverse monoid has rank at least two.
Decidability for systems of typed equations over a free inverse monoid with
one irreducible variable and at least one unbalanced equation is proved with
the same complexity for the upper bound.
Our results improve known complexity bounds by Deis, Meakin, and Senizergues:
Equations in free inverse monoids, 2007.
Our results also apply to larger families of equations where no decidability
has been previously known.Comment: 28 pages. The conference version of this paper appeared in the
proceedings of 10th International Computer Science Symposium in Russia, CSR
2015, Listvyanka, Russia, July 13-17, 2015. Springer LNCS 9139, pp. 173-188
(2015
A randomized trial of an intervention to improve use and adherence to effective coronary heart disease prevention strategies
<p>Abstract</p> <p>Background</p> <p>Efficacious strategies for the primary prevention of coronary heart disease (CHD) are underused, and, when used, have low adherence. Existing efforts to improve use and adherence to these efficacious strategies have been so intensive that they are impractical for clinical practice.</p> <p>Methods</p> <p>We conducted a randomized trial of a CHD prevention intervention (including a computerized decision aid and automated tailored adherence messages) at one university general internal medicine practice. After obtaining informed consent and collecting baseline data, we randomized patients (men and women age 40-79 with no prior history of cardiovascular disease) to either the intervention or usual care. We then saw them for two additional study visits over 3 months. For intervention participants, we administered the decision aid at the primary study visit (1 week after baseline visit) and then mailed 3 tailored adherence reminders at 2, 4, and 6 weeks. We assessed our outcomes (including the predicted likelihood of angina, myocardial infarction, and CHD death over 10 years (CHD risk) and self-reported adherence) between groups at 3 month follow-up. Data collection occurred from June 2007 through December 2009. All study procedures were IRB approved.</p> <p>Results</p> <p>We randomized 160 eligible patients (81 intervention; 79 control) and followed 96% to study conclusion. Mean predicted CHD risk at baseline was 11.3%. The intervention increased self-reported adherence to chosen risk reducing strategies by 25 percentage points (95% CI 8% to 42%), with the biggest effect for aspirin. It also changed predicted CHD risk by -1.1% (95% CI -0.16% to -2%), with a larger effect in a pre-specified subgroup of high risk patients.</p> <p>Conclusion</p> <p>A computerized intervention that involves patients in CHD decision making and supports adherence to effective prevention strategies can improve adherence and reduce predicted CHD risk.</p> <p>Clinical trials registration number</p> <p>ClinicalTrials.gov: <a href="http://www.clinicaltrials.gov/ct2/show/NCT00494052">NCT00494052</a></p
The genetic architecture of membranous nephropathy and its potential to improve non-invasive diagnosis
Membranous Nephropathy (MN) is a rare autoimmune cause of kidney failure. Here we report a genome-wide association study (GWAS) for primary MN in 3,782 cases and 9,038 controls of East Asian and European ancestries. We discover two previously unreported loci, NFKB1 (ï»żrs230540, OR = 1.25, P = 3.4 Ă 10-12) and IRF4 (ï»żrs9405192, OR = 1.29, P = ï»ż1.4 Ă 10-14), fine-map the PLA2R1 locus (ï»żrs17831251, OR = 2.25, P = 4.7 Ă 10-103) and report ancestry-specific effects of three classical HLA alleles: DRB1*1501 in East Asians (OR = 3.81, P = 2.0 Ă 10-49), DQA1*0501 in Europeans (OR = 2.88, P = 5.7 Ă 10-93), and DRB1*0301 in both ethnicities (OR = 3.50, P = 9.2 Ă 10-23 and OR = 3.39, P = 5.2 Ă 10-82, respectively). GWAS loci explain 32% of disease risk in East Asians and 25% in Europeans, and correctly re-classify 20-37% of the cases in validation cohorts that are antibody-negative by the serum anti-PLA2R ELISA diagnostic test. Our findings highlight an unusual genetic architecture of MN, with four loci and their interactions accounting for nearly one-third of the disease risk
Search for the supersymmetric partner of the top quark in ppÌ collisions at âs=1.96ââTeV
17 pages, 11 figures. Published in Phys.Rev.D82:092001,2010.We present a search for the lightest supersymmetric partner of the top quark in proton-antiproton collisions at a center-of-mass energy âs=1.96ââTeV. This search was conducted within the framework of the R parity conserving minimal supersymmetric extension of the standard model, assuming the stop decays dominantly to a lepton, a sneutrino, and a bottom quark. We searched for events with two oppositely-charged leptons, at least one jet, and missing transverse energy in a data sample corresponding to an integrated luminosity of 1ââfb-1 collected by the Collider Detector at Fermilab experiment. No significant evidence of a stop quark signal was found. Exclusion limits at 95% confidence level in the stop quark versus sneutrino mass plane are set. Stop quark masses up to 180ââGeV/c2 are excluded for sneutrino masses around 45ââGeV/c2, and sneutrino masses up to 116ââGeV/c2 are excluded for stop quark masses around 150ââGeV/c2.Peer reviewe
Predictors of weight loss in young adults who are over-weight or obese and have psychosocial problems: a post hoc analysis
Evidence for the charmless annihilation decay mode
We search for annihilation decay modes of neutral mesons into pairs of
charmless charged hadrons with the upgraded Collider Detector at the Fermilab
Tevatron. Using a data sample corresponding to 6 fb of integrated
luminosity, we obtain the first evidence for the decay,
with a significance of , and a measured branching ratio
. A search for the mode in the same
sample yields a significance of , and a central value estimate
.Comment: 8 pages, 3 figures, 2 tables. Accepted by Phys.Rev.Let
Search for the Rare Radiative Decay: in \ppbar\ Collisions at TeV
We present a search for the rare radiative decay \wpigamma\ using data
corresponding to an integrated luminosity of 4.3 \invfb\ of proton-antiproton
collisions at a center of mass energy of 1.96 TeV collected by the CDF
experiment at Fermilab. As no statistically significant signal is observed, we
set a 95% confidence level upper limit on the relative branching fraction
\bratio\ at , a factor of 10 improvement over the previous
limit
Search for New Particles in Final States with Large Jet Multiplicities and Missing Transverse Energy in ppbar Collisions at sqrt(s) = 1.96 TeV
We present a search for a new particle T' decaying to a top quark via T' -> t
+ X, where X goes undetected. We use a data sample corresponding to 5.7 fb-1 of
integrated luminosity of ppbar collisions with sqrt{s} = 1.96 TeV, collected at
Fermilab by the CDF II detector. Our search for pair production of T' is
focused on the hadronic decay channel, ppbar -> T'T' -> tt +XX -> bbqqqq + XX.
We interpret our results in terms of a model where T' is an exotic fourth
generation quark and X is a dark matter candidate. The data are consistent with
standard model expectations. We set a limit on the generic production of
T'T'->tt+XX, excluding the fourth generation exotic quarks T' at 95% confidence
level up to m_T' = 400 GeV/c2 for m_X < 70 GeV/c2
Measurement of the branching fraction B(Î0bâÎ+cÏâÏ+Ïâ) at CDF
We report an analysis of the Î0bâÎ+cÏâÏ+Ïâ decay in a data sample collected by the CDF II detector at the Fermilab Tevatron corresponding to 2.4ââfbâ1 of integrated luminosity. We reconstruct the currently largest samples of the decay modes Î0bâÎc(2595)+Ïâ (with Îc(2595)+âÎ+cÏ+Ïâ), Î0bâÎc(2625)+Ïâ (with Îc(2625)+âÎ+cÏ+Ïâ), Î0bâÎŁc(2455)++ÏâÏâ (with ÎŁc(2455)++âÎ+cÏ+), and Î0bâÎŁc(2455)0Ï+Ïâ (with ÎŁc(2455)0âÎ+cÏâ) and measure the branching fractions relative to the Î0bâÎ+cÏâ branching fraction. We measure the ratio B(Î0bâÎ+cÏâÏ+Ïâ)/B(Î0bâÎ+cÏâ)=3.04±0.33(stat)+0.70â0.55(syst) which is used to derive B(Î0bâÎ+cÏâÏ+Ïâ)=(26.8+11.9â11.2)Ă10â3
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