Final state hadronic interactions and non-resonant B±→K±π+π−B^\pm\to K^\pm\pi^+\pi^- decays

We evaluate the non-resonant decay amplitude of the process $B^\pm\to K^\pm\pi^+ \pi^-$ using an approach based on final state hadronic interactions described in terms of meson exchanges. We conclude that this mechanism generates inhomogeneities in the Dalitz plot of the B decay.Comment: 6 pages, 5 figures. Major changes. Version accepted for publication in Phys. Lett.

The role of trauma team activation by emergency physicians on outcomes in severe trauma patients

AbstractBackgroundIn our region, trauma team activation (TTA) is initiated by emergency physicians once an injured patient meets any of the criteria of TTA after the injured patient arrives at the emergency department (ED).PurposeTo evaluate the role of TTA on outcomes in patients with severe trauma.MethodsAll trauma patients who had injury severity score (ISS) >15 and were admitted from ED between January 2010 to December 2010 were included in the study. Mann–Whitney U test (non-normal distribution) or Student's t test (normal distribution) for continuous variables and Fisher exact test or Chi-square test for categorical variables were used to compare the statistically significant differences between TTA and non-TTA groups. Logistic regression was applied to determine any significant differences found in the statistical analysis for 30-day mortality.ResultsA total of 231 patients were signed up in the study. The TTA group had shorter time from ED to operation room (170 minutes vs. 534 minutes, p = 0.02) and tended to have more emergent operations (42.7% vs. 23.2%, p = 0.002). Emergent operation [odds ratio (OR), 0.34; 95% confidence interval (CI), 0.12–0.92, p = 0.035) was associated with lower mortality while ISS > 25 (OR, 7.48; 95% CI, 2.48–22.57, p < 0.0001), Glasgow coma scale score <13 (OR, 32.1; 95% CI, 4.30–94.6, p < 0.0001), hypotension (OR, 3.0; 95% CI, 1.1–7.9, p = 0.03), and coagulopathy (OR, 9.3; 95% CI, 1.2–71.4, p = 0.033) were associated with higher mortality.ConclusionThis study shows that TTA may shorten the time from ED to operation room in trauma patients with an ISS > 15

Effectiveness of influenza vaccination in patients with end-stage renal disease receiving hemodialysis: a population-based study.

BackgroundLittle is known on the effectiveness of influenza vaccine in ESRD patients. This study compared the incidence of hospitalization, morbidity, and mortality in end-stage renal disease (ESRD) patients undergoing hemodialysis (HD) between cohorts with and without influenza vaccination.MethodsWe used the insurance claims data from 1998 to 2009 in Taiwan to determine the incidence of these events within one year after influenza vaccination in the vaccine (N = 831) and the non-vaccine (N = 3187) cohorts. The vaccine cohort to the non-vaccine cohort incidence rate ratio and hazard ratio (HR) of morbidities and mortality were measured.ResultsThe age-specific analysis showed that the elderly in the vaccine cohort had lower hospitalization rate (100.8 vs. 133.9 per 100 person-years), contributing to an overall HR of 0.81 (95% confidence interval (CI) 0.72-0.90). The vaccine cohort also had an adjusted HR of 0.85 [95% CI 0.75-0.96] for heart disease. The corresponding incidence of pneumonia and influenza was 22.4 versus 17.2 per 100 person-years, but with an adjusted HR of 0.80 (95% CI 0.64-1.02). The vaccine cohort had lowered risks than the non-vaccine cohort for intensive care unit (ICU) admission (adjusted HR 0.20, 95% CI 0.12-0.33) and mortality (adjusted HR 0.50, 95% CI 0.41-0.60). The time-dependent Cox model revealed an overall adjusted HR for mortality of 0.30 (95% CI 0.26-0.35) after counting vaccination for multi-years.ConclusionsESRD patients with HD receiving the influenza vaccination could have reduced risks of pneumonia/influenza and other morbidities, ICU stay, hospitalization and death, particularly for the elderly

Theory of orbital magnetization in disordered systems

We present a general formula of the orbital magnetization of disordered systems based on the Keldysh Green's function theory in the gauge-covariant Wigner space. In our approach, the gauge invariance of physical quantities is ensured from the very beginning, and the vertex corrections are easily included. Our formula applies not only for insulators but also for metallic systems where the quasiparicle behavior is usually strongly modified by the disorder scattering. In the absence of disorders, our formula recovers the previous results obtained from the semiclassical theory and the perturbation theory. As an application, we calculate the orbital magnetization of a weakly disordered two-dimensional electron gas with Rashba spin-orbit coupling. We find that for the short range disorder scattering, its major effect is to the shifting of the distribution of orbital magnetization corresponding to the quasiparticle energy renormalization.Comment: 10 pages, 5 figure

VI-Band Follow-Up Observations of Ultra-Long-Period Cepheid Candidates in M31

The ultra-long period Cepheids (ULPCs) are classical Cepheids with pulsation periods exceeding $\approx 80$ days. The intrinsic brightness of ULPCs are ~1 to ~3 mag brighter than their shorter period counterparts. This makes them attractive in future distance scale work to derive distances beyond the limit set by the shorter period Cepheids. We have initiated a program to search for ULPCs in M31, using the single-band data taken from the Palomar Transient Factory, and identified eight possible candidates. In this work, we presented the VI-band follow-up observations of these eight candidates. Based on our VI-band light curves of these candidates and their locations in the color-magnitude diagram and the Period-Wesenheit diagram, we verify two candidates as being truly ULPCs. The six other candidates are most likely other kinds of long-period variables. With the two confirmed M31 ULPCs, we tested the applicability of ULPCs in distance scale work by deriving the distance modulus of M31. It was found to be $\mu_{M31,ULPC}=24.30\pm0.76$ mag. The large error in the derived distance modulus, together with the large intrinsic dispersion of the Period-Wesenheit (PW) relation and the small number of ULPCs in a given host galaxy, means that the question of the suitability of ULPCs as standard candles is still open. Further work is needed to enlarge the sample of calibrating ULPCs and reduce the intrinsic dispersion of the PW relation before re-considering ULPCs as suitable distance indicators.Comment: 13 pages, with 14 Figures and 4 Tables (one online table). AJ accepte

Effective Theories and Electroweak Precision Constraints

This is a pedagogical and self-contained review on obtaining electroweak precision constraints on TeV scale new physics using the effective theory method. We identify a set of relevant effective operators in the standard model and calculate from them corrections to all major electroweak precision observables. The corrections are compared with data to put constraints on the effective operators. Various approaches and applications in the literature are reviewed.Comment: 31 pages. To appear in International Journal of Modern Physics

Discovery of Protein Phosphorylation Motifs through Exploratory Data Analysis

BACKGROUND: The need for efficient algorithms to uncover biologically relevant phosphorylation motifs has become very important with rapid expansion of the proteomic sequence database along with a plethora of new information on phosphorylation sites. Here we present a novel unsupervised method, called Motif Finder (in short, F-Motif) for identification of phosphorylation motifs. F-Motif uses clustering of sequence information represented by numerical features that exploit the statistical information hidden in some foreground data. Furthermore, these identified motifs are then filtered to find "actual" motifs with statistically significant motif scores. RESULTS AND DISCUSSION: We have applied F-Motif to several new and existing data sets and compared its performance with two well known state-of-the-art methods. In almost all cases F-Motif could identify all statistically significant motifs extracted by the state-of-the-art methods. More importantly, in addition to this, F-Motif uncovers several novel motifs. We have demonstrated using clues from the literature that most of these new motifs discovered by F-Motif are indeed novel. We have also found some interesting phenomena. For example, for CK2 kinase, the conserved sites appear only on the right side of S. However, for CDK kinase, the adjacent site on the right of S is conserved with residue P. In addition, three different encoding methods, including a novel position contrast matrix (PCM) and the simplest binary coding, are used and the ability of F-motif to discover motifs remains quite robust with respect to encoding schemes. CONCLUSIONS: An iterative algorithm proposed here uses exploratory data analysis to discover motifs from phosphorylated data. The effectiveness of F-Motif has been demonstrated using several real data sets as well as using a synthetic data set. The method is quite general in nature and can be used to find other types of motifs also. We have also provided a server for F-Motif at http://f-motif.classcloud.org/, http://bio.classcloud.org/f-motif/ or http://ymu.classcloud.org/f-motif/

Reduced Ca2+ transport across sarcolemma but enhanced spontaneous activity in cardiomyocytes isolated from left atrium-pulmonary veins tissue of myopathic hamster

<p>Abstract</p> <p>Background</p> <p>Several lines of evidence point to a particularly important role of the left atrium (LA) in initiating and maintaining atrial fibrillation (AF). This role may be related to the location of pulmonary veins (PVs) in the LA. The aim of the present study was to investigate the action potential (AP) and ionic currents in LA-PV cardiomyocytes isolated from Bio14.6 myopathic Syrian hamsters (36-57 week-old) versus age-matched F1B healthy control hamsters.</p> <p>Methods and Results</p> <p>Whole-cell patch-clamp techniques were used to record AP in current-clamp mode and ionic currents in voltage-clamp mode. The results obtained show that in both healthy and myopathic LA-PV tissue spontaneously discharging cardiomyocytes can be found, but they are more numerous in myopathic (9/29) than in healthy hamsters (4/42, p < 0.05 by χ²analysis). Myopathic myocytes have shorter AP duration (APD) with smaller I_Ca,Land I_NCXthan the healthy control. The currents I_TO, I_K, I_K1and I_Ca,Tare not significantly different in myopathic versus healthy cells.</p> <p>Conclusions</p> <p>Our results indicate that in myopathic Syrian hamsters LA-PV cardiomyocytes are more prone to automatic rhythms. Also, they show altered electrophysiologic properties, which may be due to abnormal Ca²⁺channels and may account for contractile dysfunction.</p

In vitro analysis of phosphorothioate modification of DNA reveals substrate recognition by a multiprotein complex

A wide variety of prokaryotes possess DNA modifications consisting of sequence-specific phosphorothioates (PT) inserted by members of a five-gene cluster. Recent genome mapping studies revealed two unusual features of PT modifications: short consensus sequences and partial modification of a specific genomic site in a population of bacteria. To better understand the mechanism of target selection of PT modifications that underlies these features, we characterized the substrate recognition of the PT-modifying enzymes termed DptC, D and E in a cell extract system from Salmonella. The results revealed that double-stranded oligodeoxynucleotides underwent de novo PT modification in vitro, with the same modification pattern as in vivo, i. e., GpsAAC/GpsTTC motif. Unexpectedly, in these in vitro analyses we observed no significant effect on PT modification by sequences flanking GAAC/GTTC motif, while PT also occurred in the GAAC/GTTC motif that could not be modified in vivo. Hemi-PT DNA also served as substrate of the PT-modifying enzymes, but not single-stranded DNA. The PT-modifying enzymes were then found to function as a large protein complex, with all of three subunits in tetrameric conformations. This study provided the first demonstration of in vitro DNA PT modification by PT-modifying enzymes that function as a large protein complex.National Natural Science Foundation (China) (Grant 31470183)National Natural Science Foundation (China) (Grant 31400029)National Natural Science Foundation (China) (Grant 31170085)National Natural Science Foundation (China) (Grant 30570400)National Natural Science Foundation (China) (Grant 31070058)China. Ministry of Science and Technology (Grant 2012CB721004)China. Ministry of Science and Technology (Grant 2009ZX09501-008)Shanghai Municipal Council of Science and Technology (Shanghai Pujiang Program Grant 12PJD021)China Scholarship CouncilNational Science Foundation (U.S.) (Grant CHE-1019990)National Institute of Environmental Health Sciences (Grant ES002109)Singapore. National Research Foundation (Singapore-MIT Alliance for Research and Technology