Beta-blockers and physical frailty in patients with end-stage liver disease.

AimTo investigate beta-blocker (BB) use in patients with cirrhosis and determine their effects on physical frailty and overall survival.MethodsAdult outpatients with cirrhosis listed for liver transplantation underwent testing of physical frailty using the performance-based Liver Frailty Index, comprised of chair stands, grip strength, and balance testing, as well as self-reported assessments of exhaustion and physical activity. BB use was assessed from medical chart review. Univariable and multivariable logistic regression were performed to determine BB use and their association with measures of physical frailty. Competing risk analyses were performed to determine the effect of BB use on wait-list mortality, as defined by death or delisting for being too sick for transplant.ResultsOf 344 patients, 35% were female, median age was 60, median model for end stage liver disease was 15, and 53% were prescribed a BB. Compared to those not on BB, patients on BB were similar except for percentage female (25% vs 46%; P < 0.001) and BMI (29 vs 28; P = 0.008). With respect to tests of physical frailty, BB use was not associated with increased odds of frailty (by the Liver Frailty Index), exhaustion, or low physical activity. BB use was, however, significantly associated with a decreased adjusted risk of mortality (SHR 0.55; P = 0.005).ConclusionIn patients with cirrhosis awaiting liver transplantation, BB use is not associated with physical frailty. We confirmed the known survival benefits with BB use, and concerns about adverse effects should not deter their utilization when indicated

Modeling of a Cantilever-Based Near-Field Scanning Microwave Microscope

We present a detailed modeling and characterization of our scalable microwave nanoprobe, which is a micro-fabricated cantilever-based scanning microwave probe with separated excitation and sensing electrodes. Using finite-element analysis, the tip-sample interaction is modeled as small impedance changes between the tip electrode and the ground at our working frequencies near 1GHz. The equivalent lumped elements of the cantilever can be determined by transmission line simulation of the matching network, which routes the cantilever signals to 50 Ohm feed lines. In the microwave electronics, the background common-mode signal is cancelled before the amplifier stage so that high sensitivity (below 1 atto-Farad capacitance changes) is obtained. Experimental characterization of the microwave probes was performed on ion-implanted Si wafers and patterned semiconductor samples. Pure electrical or topographical signals can be realized using different reflection modes of the probe.Comment: 7 figure

A chromatic transient visual evoked potential based encoding/decoding approach for brain-computer interface

This paper presents a new encoding/decoding approach to brain-computer interface (BCI) based on chromatic transient visual evoked potential (CTVEP). The proposed CTVEP-based encoding/decoding approach is designed to provide a safer and more comfortable stimulation method than the conventional VEP-based stimulation methods for BCI without loss of efficiency. For this purpose, low-frequency isoluminant chromatic stimuli are time-encoded to serve as different input commands for BCI control, and the superior comfortableness of the proposed stimulation method is validated by a survey. A combination of diversified signal processing techniques are further employed to decode the information from CTVEP. Based on experimental results, a properly designed configuration of the CTVEP-based stimulation method and a tailored signal processing framework are developed. It is demonstrated that high performance (at information transfer rate: 58.0 bits/min, accuracy: 94.9%, false alarm rate: 1.3%) for BCI can be achieved by means of the CTVEP-based encoding/decoding approach. It turns out that to achieve such good performance, only simple signal processing algorithms with very low computational complexity are required, which makes the method suitable for the development of a practical BCI system. A preliminary prototype of such a system has been implemented with demonstrated applicability. © 2011 IEEE.published_or_final_versio

Three-jet cross sections in hadron-hadron collisions at next-to-leading order

We present a new QCD event generator for hadron collider which can calculate one-, two- and three-jet cross sections at next-to-leading order accuracy. In this letter we study the transverse energy spectrum of three-jet hadronic events using the kT algorithm. We show that the next-to-leading order correction significantly reduces the renormalization and factorization scale dependence of the three-jet cross section.Comment: 4 pages, 4 figures, REVTEX

Multi-jet cross sections in deep inelastic scattering at next-to-leading order

We present the perturbative prediction for three-jet production cross section in DIS at the NLO accuracy. We study the dependence on the renormalization and factorization scales of exclusive three-jet cross section. The perturbative prediction for the three-jet differential distribution as a function of the momentum transfer is compared to the corresponding data obtained by the H1 collaboration at HERA.Comment: 5 pages, 3 figure

Visual Functions and Interocular Interactions in Anisometropic Children with and without Amblyopia

Purpose.: In uncorrected anisometropia, protracted dichoptic stimulation may result in interocular inhibition, which may be a contributing factor in amblyopia development. This study investigates the relationship between interocular interactions and anisometropic amblyopia. Methods.: Three visual functions (low-contrast acuity, contrast sensitivity, and alignment sensitivity) were measured in the nondominant eye of 44 children aged 5 to 11 years: 10 with normal vision, 17 with anisometropia without amblyopia, and 17 with anisometropic amblyopia. The dominant eye was either fully or partially occluded. The difference in nondominant eye visual function between the full-and partial-occlusion conditions was termed the interaction index. The index of each visual function was compared between subject groups. A higher index indicates stronger inhibition of nondominant eye function with partial occlusion of the dominant eye. Amblyopic children had 6 months of therapy (refractive correction and occlusion), and the reduction in interocular difference in high-contrast acuity was regarded as the treatment outcome. The relationships of the interaction index with the degree of anisometropia, the severity of amblyopia, and the treatment outcomes were examined. Results.: The acuity interaction index was significantly higher in anisometropic children with amblyopia than in those without (P = 0.003). It was positively correlated with the degree of anisometropia (r s = 0.35, P = 0.042) and the amblyopic treatment outcomes (r s = 0.54, P = 0.038). No such difference or association was found between the contrast sensitivity or alignment sensitivity interaction index and anisometropic amblyopia. Conclusions.: Interocular interactions are associated with amblyopia, the degree of anisometropia, and amblyopia treatment outcomes, but these associations are visual function dependent

On the Kinetic Roughening in Polymer Film Growth by Vapor Deposition

This is a Comment on a recent publication: Y.-P. Zhao et al., Phys. Rev. Lett. 85, 3229 (2000). In the Letter, the authors report on an experimental investigation of polymeric (p-xylene) thin film growth and propose a new universality class not previously known. Here, we point out that the critical exponents reported in the Letter are consistent with the critical exponents of Das Sarma-Tamborenea growth model.Comment: 2 pages, 1 figure include