Exact Maximal Height Distribution of Fluctuating Interfaces

We present an exact solution for the distribution P(h_m,L) of the maximal height h_m (measured with respect to the average spatial height) in the steady state of a fluctuating Edwards-Wilkinson interface in a one dimensional system of size L with both periodic and free boundary conditions. For the periodic case, we show that P(h_m,L)=L^{-1/2}f(h_m L^{-1/2}) for all L where the function f(x) is the Airy distribution function that describes the probability density of the area under a Brownian excursion over a unit interval. For the free boundary case, the same scaling holds but the scaling function is different from that of the periodic case. Numerical simulations are in excellent agreement with our analytical results. Our results provide an exactly solvable case for the distribution of extremum of a set of strongly correlated random variables.Comment: 4 pages revtex (two-column), 1 .eps figure include

Catalyzed oxidation of aniline by hydrogen peroxide in the presence of cnts: A Possible case of a nanodimension reaction

The oxidation of aniline by hydrogen peroxide produces nitrosobenzene as the initial product, which undergoes further oxidation to nitrobenzene. The nitrosobenzene formation is catalyzed by functionalized multiwalled carbon nanotubes (CNT) followed by a coupling reaction between nitrosobenzene and aniline to produce azobenzene. This reaction proceeds rapidly resulting in the UV-VIS absorption spectrum showing a maxima at 327 nm and 425 nm. The nitrosobenzene yield in the presence of CNTs is controlled by the amount present in the medium. As the reaction is not catalyzed by unfunctionalized CNTs or graphitic particles, the uniqueness of the functionalized multiwalled CNTs in this catalysis suggests a nano dimensional reaction pathway

Discolored1 (DSC1) is an ADP-Ribosylation Factor-GTPase Activating Protein Required to Maintain Differentiation of Maize Kernel Structures

The embryo and endosperm are the products of double fertilization and comprise the clonally distinct products of angiosperm seed development. Recessive mutations in the maize gene discolored1 (dsc1) condition inviable seed that are defective in both embryo and endosperm development. Here, detailed phenotypic analyses illustrate that discolored mutant kernels are able to establish, but fail to maintain, differentiated embryo, and endosperm structures. Development of the discolored mutant embryo and endosperm is normal albeit delayed, prior to the abortion and subsequent degeneration of all differentiated kernel structures. Using a genomic fragment that was previously isolated by transposon tagging, the full length dsc1 transcript is identified and shown to encode an ADP-ribosylation factor-GTPase activating protein (ARF-GAP) that co-localizes with the trans-Golgi network/early endosomes and the plasma membrane during transient expression assays in N. benthamiana leaves. DSC1 function during endomembrane trafficking and the maintenance of maize kernel differentiation is discussed

Towards Precision LSST Weak-Lensing Measurement - I: Impacts of Atmospheric Turbulence and Optical Aberration

The weak-lensing science of the LSST project drives the need to carefully model and separate the instrumental artifacts from the intrinsic lensing signal. The dominant source of the systematics for all ground based telescopes is the spatial correlation of the PSF modulated by both atmospheric turbulence and optical aberrations. In this paper, we present a full FOV simulation of the LSST images by modeling both the atmosphere and the telescope optics with the most current data for the telescope specifications and the environment. To simulate the effects of atmospheric turbulence, we generated six-layer phase screens with the parameters estimated from the on-site measurements. For the optics, we combined the ray-tracing tool ZEMAX and our simulated focal plane data to introduce realistic aberrations and focal plane height fluctuations. Although this expected flatness deviation for LSST is small compared with that of other existing cameras, the fast f-ratio of the LSST optics makes this focal plane flatness variation and the resulting PSF discontinuities across the CCD boundaries significant challenges in our removal of the systematics. We resolve this complication by performing PCA CCD-by-CCD, and interpolating the basis functions using conventional polynomials. We demonstrate that this PSF correction scheme reduces the residual PSF ellipticity correlation below 10^-7 over the cosmologically interesting scale. From a null test using HST/UDF galaxy images without input shear, we verify that the amplitude of the galaxy ellipticity correlation function, after the PSF correction, is consistent with the shot noise set by the finite number of objects. Therefore, we conclude that the current optical design and specification for the accuracy in the focal plane assembly are sufficient to enable the control of the PSF systematics required for weak-lensing science with the LSST.Comment: Accepted to PASP. High-resolution version is available at http://dls.physics.ucdavis.edu/~mkjee/LSST_weak_lensing_simulation.pd

Socioeconomic inequalities in smoking and drinking in adolescence:social network dynamics

BackgroundNetwork-based interventions have the potential to prevent socioeconomic inequalities in health behaviors but require a good understanding of the underlying social network mechanisms. We investigated whether (1) adolescents selected friends with a similar socioeconomic status (SES), (2) smoking and alcohol consumption spread in networks, and (3) the exclusion of non-smokers or non-drinkers differed between SES groups.MethodsWe applied Stochastic Actor Oriented Models to the complete social network data (“Wired into Each Other” data) of 253 adolescents in eight Hungarian secondary school classes over three waves between 2010 and 2013. SES was measured based on entitlement to an income-tested regular child protection benefit.ResultsHigh SES adolescents were most likely to form friendships with peers from their own SES group (odds ratio [OR] = 1.1, 95% Confidence Interval [CI] = 1.0-1.1). Adolescents adjusted their smoking behavior (OR = 24.0, 95% CI 1.3-454.9) but not their alcohol consumption (OR = 1.6, 95% CI 0.6-4.4) to emulate the behavior of their friends. Smokers did not differ from non-smokers in the likelihood of receiving a friendship nomination (OR = 1.0, 95% CI 0.9-1.1), regardless of their SES. Alcohol consumers received significantly more friendship nominations than non-consumers (OR = 1.2, 95% CI 1.0-1.3), but this association was not significantly different according to SES.ConclusionsSocioeconomic inequalities in health behaviors were driven by preferences to form friendships within their own SES group and the spread of smoking and alcohol consumption in the network. These inequalities were not amplified by SES differences in encouraging smoking or drinking.Main messages: In three waves of observations in a Hungarian adolescent cohort, the study found social network effects for inequalities in smoking and alcohol consumption

Socioeconomic inequalities in smoking and drinking in adolescence:social network dynamics

BackgroundNetwork-based interventions have the potential to prevent socioeconomic inequalities in health behaviors but require a good understanding of the underlying social network mechanisms. We investigated whether (1) adolescents selected friends with a similar socioeconomic status (SES), (2) smoking and alcohol consumption spread in networks, and (3) the exclusion of non-smokers or non-drinkers differed between SES groups.MethodsWe applied Stochastic Actor Oriented Models to the complete social network data (“Wired into Each Other” data) of 253 adolescents in eight Hungarian secondary school classes over three waves between 2010 and 2013. SES was measured based on entitlement to an income-tested regular child protection benefit.ResultsHigh SES adolescents were most likely to form friendships with peers from their own SES group (odds ratio [OR] = 1.1, 95% Confidence Interval [CI] = 1.0-1.1). Adolescents adjusted their smoking behavior (OR = 24.0, 95% CI 1.3-454.9) but not their alcohol consumption (OR = 1.6, 95% CI 0.6-4.4) to emulate the behavior of their friends. Smokers did not differ from non-smokers in the likelihood of receiving a friendship nomination (OR = 1.0, 95% CI 0.9-1.1), regardless of their SES. Alcohol consumers received significantly more friendship nominations than non-consumers (OR = 1.2, 95% CI 1.0-1.3), but this association was not significantly different according to SES.ConclusionsSocioeconomic inequalities in health behaviors were driven by preferences to form friendships within their own SES group and the spread of smoking and alcohol consumption in the network. These inequalities were not amplified by SES differences in encouraging smoking or drinking.Main messages: In three waves of observations in a Hungarian adolescent cohort, the study found social network effects for inequalities in smoking and alcohol consumption

Conversion of Aniline to Azobenzene at Functionalized Carbon Nanotubes: A Possible Case of a Nanodimensional Reaction

Aniline is oxidized to nitrosobenzene as the initial product, which undergoes further oxidation to nitrobenzene. The nitrosobenzene formation is catalyzed by functionalized multiwalled carbon nanotubes (CNT) followed by a coupling reaction between nitrosobenzene and aniline to produce azobenzene. This coupling requires close proximity of the reactants. It proceeds rapidly resulting in the UV-VIS absorption spectrum showing maxima at 327 nm and 425 nm. The nitrosobenzene yield in the presence of CNTs is controlled by the amount present in the medium. As the reaction is not catalyzed by unfunctionalized CNTs or graphitic particles, the uniqueness of the functionalized multiwalled CNTs in this catalysis suggests a nanodimensional reaction pathway