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Universal emulsion stabilization from the arrested adsorption of rough particles at liquid-liquid interfaces
Surface heterogeneities, including roughness, significantly affect the adsorption, motion and interactions of particles at fluid interfaces. However, a systematic experimental study, linking surface roughness to particle wettability at a microscopic level, is currently missing. Here we synthesize a library of all-silica microparticles with uniform surface chemistry, but tuneable surface roughness and study their spontaneous adsorption at oil-water interfaces. We demonstrate that surface roughness strongly pins the particles' contact lines and arrests their adsorption in long-lived metastable positions, and we directly measure the roughness-induced interface deformations around isolated particles. Pinning imparts tremendous contact angle hysteresis, which can practically invert the particle wettability for sufficient roughness, irrespective of their chemical nature. As a unique consequence, the same rough particles stabilize both water-in-oil and oil-in-water emulsions depending on the phase they are initially dispersed in. These results both shed light on fundamental phenomena concerning particle adsorption at fluid interfaces and indicate future design rules for particle-based emulsifiers
Development of a theory-based questionnaire to assess structure and control in parent feeding (SCPF)
Abstract
Background
Parents shape children\u2019s eating environments and act as powerful socialization agents, impacting young children\u2019s behavioral controls of food intake. Most feeding measures assess parents\u2019 use of control to manage children\u2019s intake of energy dense foods. The Structure and Control in Parent Feeding (SCPF) questionnaire was developed to assess more positive aspects of feeding practices with their young children \u2014setting limits, providing routines\u2014that promote self-regulation, as well as controlling feeding practices.
Methods
A mixed method approach was used to develop the SCPF. In 2013, cognitive interviews informed the modification, deletion and/or replacement of items. In 2014, the survey was distributed statewide to mothers of toddlers aged 12 to 36\ua0months participating in the Women, Infants, and Children program. In 2016, exploratory factor analyses was conducted to test our theoretical parenting model and content validity and criterion validity were assessed ( n \u2009=\u2009334).
Results
Exploratory factor analysis (EFA) and second-order EFA revealed a 2-factor, 22-item Structure model and a 2-factor, 12-item Control model. Internal consistencies for all factors exceeded 0.70. As predicted, the Structure superfactor was positivity associated with responsiveness, whereas the Control superfactor was positively associated with demandingness on the Caregiver\u2019s Feeding Styles Questionnaire. The Structure subscales were also positively associated with mealtime behaviors and Control subscales were positively associated with control-oriented feeding measures from the Control in Parent Feeding Practices questionnaire.
Conclusion
The SCPF questionnaire is a reliable tool that can be used to assess aspects of structure- and control-based feeding practices to better understand how parents feed their toddlers
Characterization of ellipses as uniformly dense sets with respect to a family of convex bodies
Let K \subset R^N be a convex body containing the origin. A measurable set G
\subset R^N with positive Lebesgue measure is said to be uniformly K-dense if,
for any fixed r > 0, the measure of G \cap (x + rK) is constant when x varies
on the boundary of G (here, x + rK denotes a translation of a dilation of K).
We first prove that G must always be strictly convex and at least C1,1-regular;
also, if K is centrally symmetric, K must be strictly convex, C1,1-regular and
such that K = G - G up to homotheties; this implies in turn that G must be
C2,1- regular. Then for N = 2, we prove that G is uniformly K-dense if and only
if K and G are homothetic to the same ellipse. This result was already proven
by Amar, Berrone and Gianni in [3]. However, our proof removes their regularity
assumptions on K and G and, more importantly, it is susceptible to be
generalized to higher dimension since, by the use of Minkowski's inequality and
an affine inequality, avoids the delicate computations of the higher-order
terms in the Taylor expansion near r = 0 for the measure of G\cap(x+rK) (needed
in [3])
More Rapid Increase in BMI from Age 5â15 is Associated with Elevated Weight Status at Age 24 among Non-Hispanic White Females
Background: A rapidly increasing BMI trajectory throughout childhood is associated with negative health outcomes in adulthood such as obesity, cardiovascular disease, and diabetes. The purpose of the current study was to assess whether BMI trajectories from age 5â15 predicted changes in weight and BMI from adolescence to adulthood, and dieting-related behaviors in young adulthood.
Methods: Non-Hispanic White female participants from Early Dieting in Girls (n=182), a longitudinal cohort study, were followed from age 5 to 15 and completed a follow-up survey at age 24. Participants were classified by age 5â15 BMI trajectory groups: UPC, accelerated weight gain from age 5â9; DDPC, accelerated weight gain from 5 to 9 followed by a decrease; 60PT, weight tracked along 60th percentile; 50PT, weight tracked along 50th percentile. Data at age 24 included self-reported weight, height, dietary restraint, disinhibition, and dieting.
Results: Majority of participants (80.8%) completed the follow-up survey; of these participants, 60% in UPC group had obesity at age 24, compared to\u3c10% in the other 3 groups. Participants in the UPC group had greater increases in BMI since age 15, compared to the 50PT group, and trend-level greater weight increases than those in the DDPC and 60PT groups. Dietary restraint, but not disinhibition, differed across the groups.
Conclusions: Children with accelerated weight gain continued to have the greatest weight gain from adolescence to adulthood and the highest prevalence of obesity in adulthood
Three-Body and One-Body Channels of the Auger Core-Valence-Valence decay: Simplified Approach
We propose a computationally simple model of Auger and APECS line shapes from
open-band solids. Part of the intensity comes from the decay of unscreened
core-holes and is obtained by the two-body Green's function ,
as in the case of filled bands. The rest of the intensity arises from screened
core-holes and is derived using a variational description of the relaxed ground
state; this involves the two-holes-one-electron propagator , which
also contains one-hole contributions. For many transition metals, the two-hole
Green's function can be well described by the Ladder
Approximation, but the three-body Green's function poses serious further
problems. To calculate , treating electrons and holes on equal
footing, we propose a practical approach to sum the series to all orders. We
achieve that by formally rewriting the problem in terms of a fictitious
three-body interaction. Our method grants non-negative densities of states,
explains the apparent negative-U behavior of the spectra of early transition
metals and interpolates well between weak and strong coupling, as we
demonstrate by test model calculations.Comment: AMS-LaTeX file, 23 pages, 8 eps and 3 ps figures embedded in the text
with epsfig.sty and float.sty, submitted to Phys. Rev.
Genetic Inhibition of the Ubiquitin Ligase Rnf5 Attenuates Phenotypes Associated to F508del Cystic Fibrosis Mutation
Cystic fibrosis (CF) is caused by mutations in the CFTR chloride channel. Deletion of phenylalanine 508 (F508del), the most frequent CF mutation, impairs CFTR trafficking and gating. F508del-CFTR mistrafficking may be corrected by acting directly on mutant CFTR itself or by modulating expression/activity of CFTR-interacting proteins, that may thus represent potential drug targets. To evaluate possible candidates for F508del-CFTR rescue, we screened a siRNA library targeting known CFTR interactors. Our analysis identified RNF5 as a protein whose inhibition promoted significant F508del-CFTR rescue and displayed an additive effect with the investigational drug VX-809. Significantly, RNF5 loss in F508del-CFTR transgenic animals ameliorated intestinal malabsorption and concomitantly led to an increase in CFTR activity in intestinal epithelial cells. In addition, we found that RNF5 is differentially expressed in human bronchial epithelia from CF vs. control patients. Our results identify RNF5 as a target for therapeutic modalities to antagonize mutant CFTR proteins
Search for Pair-Produced Resonances Decaying to Quark Pairs in Proton-Proton Collisions at âs = 13ââTeV
A general search for the pair production of resonances, each decaying to two quarks, is reported. The search is conducted separately for heavier resonances (masses above 400 GeV), where each of the four final-state quarks generates a hadronic jet resulting in a four-jet signature, and for lighter resonances (masses between 80 and 400 GeV), where the pair of quarks from each resonance is collimated and reconstructed as a single jet resulting in a two-jet signature. In addition, a b-tagged selection is applied to target resonances with a bottom quark in the final state. The analysis uses data collected with the CMS detector at the CERN LHC, corresponding to an integrated luminosity of 35.9ââfbâ»Âč, from proton-proton collisions at a center-of-mass energy of 13 TeV. The mass spectra are analyzed for the presence of new resonances, and are found to be consistent with standard model expectations. The results are interpreted in the framework of R-parity-violating supersymmetry assuming the pair production of scalar top quarks decaying via the hadronic coupling λâČâČ312 or λâČâČ323 and upper limits on the cross section as a function of the top squark mass are set. These results probe a wider range of masses than previously explored at the LHC, and extend the top squark mass limits in the ËtâqqâČ scenario
Search for electroweak production of charginos and neutralinos in multilepton final states in proton-proton collisions at âs = 13 TeV
Results are presented from a search for the direct electroweak production of charginos and neutralinos in signatures with either two or more leptons (electrons or muons) of the same electric charge, or with three or more leptons, which can include up to two hadronically decaying tau leptons. The results are based on a sample of proton-proton collision data collected at sâ=13 TeV, recorded with the CMS detector at the LHC, corresponding to an integrated luminosity of 35.9 fbâ»Âč. The observed event yields are consistent with the expectations based on the standard model. The results are interpreted in simplified models of supersymmetry describing various scenarios for the production and decay of charginos and neutralinos. Depending on the model parameters chosen, mass values between 180 GeV and 1150 GeV are excluded at 95% CL. These results significantly extend the parameter space probed for these particles in searches at the LHC. In addition, results are presented in a form suitable for alternative theoretical interpretations
Search for Standard Model Production of Four Top Quarks with Same-Sign and Multilepton Final States in Protonâproton Collisions at âs = 13 TeV
A search for standard model production of four top quarks (ttÂŻttÂŻ) is reported using events containing at least three leptons (e,ÎŒ) or a same-sign lepton pair. The events are produced in protonâproton collisions at a center-of-mass energy of 13TeV at the LHC, and the data sample, recorded in 2016, corresponds to an integrated luminosity of 35.9fb[superscript â1]. Jet multiplicity and flavor are used to enhance signal sensitivity, and dedicated control regions are used to constrain the dominant backgrounds. The observed and expected signal significances are, respectively, 1.6 and 1.0 standard deviations, and the ttÂŻttÂŻ cross section is measured to be 16.9[superscript +13.8][subscript â11.4] fb, in agreement with next-to-leading-order standard model predictions. These results are also used to constrain the Yukawa coupling between the top quark and the Higgs boson to be less than 2.1 times its expected standard model value at 95% confidence level
Measurement of the transverse momentum spectrum of the Higgs boson produced in pp collisions at âs=8 TeV using H â WW decays
The cross section for Higgs boson production in pp collisions is studied using the H â W[superscript +]W[superscript â] decay mode, followed by leptonic decays of the W bosons to an oppositely charged electron-muon pair in the final state. The measurements are performed using data collected by the CMS experiment at the LHC at a centre-of-mass energy of 8 TeV, corresponding to an integrated luminosity of 19.4 fb[superscript â1]. The Higgs boson transverse momentum (p[subscript T]) is reconstructed using the lepton pair p[subscript T] and missing p[subscript T]. The differential cross section times branching fraction is measured as a function of the Higgs boson pTin a fiducial phase space defined to match the experimental acceptance in terms of the lepton kinematics and event topology. The production cross section times branching fraction in the fiducial phase space is measured to be 39 ± 8 (stat) ± 9 (syst) fb. The measurements are found to agree, within experimental uncertainties, with theoretical calculations based on the standard model. Keywords: Hadron-Hadron scattering (experiments), Higgs physicsNational Science Foundation (U.S.)United States. Department of Energ
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