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Solid-liquid interactions are central to diverse processes. The interaction strength can be described by the solid-liquid interfacial free energy (γ_{SL}), a quantity that is difficult to measure. Here, we present the direct experimental measurement of γ_{SL} for a variety of solid materials, from nonpolar polymers to highly wetting metals. By attaching a thin solid film on top of a liquid meniscus, we create a solid-liquid interface. The interface determines the curvature of the meniscus, analysis of which yields γ_{SL} with an uncertainty of less than 10%. Measurement of classically challenging metal-water interfaces reveals γ_{SL}∼30-60 mJ/m^{2}, demonstrating quantitatively that water-metal adhesion is 80% stronger than the cohesion energy of bulk water, and experimentally verifying previous quantum chemical calculations.

PurposeThis study measures awareness of and receptivity to the Food and Drug Administration’s This Free Life campaign seeking to change tobacco-related attitudes and beliefs among lesbian, gay, bisexual and/or transgender (LGBT) young adults.MethodsParticipants were young adults who self-identify as LGBT. The evaluation uses a treatment-control design. This study includes data from four survey rounds with participants from each round invited to participate in subsequent rounds and new participants invited to account for attrition. Bivariate analyses assess treatment-control differences in campaign awareness by round. We used multivariable logistic regression models with a time×treatment interaction and covariates to assess whether increases in awareness were greater in treatment than control from follow-ups 1 to 4. Descriptive statistics describe perceived effectiveness and models explore covariates of perceived effectiveness.ResultsAt each round, an increasing number of participants in treatment were brand aware (25%–67%) and reported high (16%–34%) and medium (16%–25%) video awareness compared with control (all pConclusionsAt follow-up 4, This Free Life reached most of the campaign audience in treatment markets and has achieved higher awareness in treatment than control markets, at individual survey rounds and over time.

Recent discoveries of exotic physical phenomena, such as unconventional superconductivity in magic-angle twisted bilayer graphene, dissipationless Dirac fermions in topological insulators, and quantum spin liquids, have triggered tremendous interest in quantum materials. The macroscopic revelation of quantum mechanical effects in quantum materials is associated with strong electron-electron correlations in the lattice, particularly where materials have reduced dimensionality. Owing to the strong correlations and confined geometry, altering atomic spacing and crystal symmetry via strain has emerged as an effective and versatile pathway for perturbing the subtle equilibrium of quantum states. This review highlights recent advances in strain-tunable quantum phenomena and functionalities, with particular focus on low-dimensional quantum materials. Experimental strategies for strain engineering are first discussed in terms of heterogeneity and elastic reconfigurability of strain distribution. The nontrivial quantum properties of several strain-quantum coupled platforms, including 2D van der Waals materials and heterostructures, topological insulators, superconducting oxides, and metal halide perovskites, are next outlined, with current challenges and future opportunities in quantum straintronics followed. Overall, strain engineering of quantum phenomena and functionalities is a rich field for fundamental research of many-body interactions and holds substantial promise for next-generation electronics capable of ultrafast, dissipationless, and secure information processing and communications.

The aim of the study was to assess awareness of and receptivity to the U.S. Food and Drug Administration's Fresh Empire tobacco public education campaign designed to reach Hip Hop-identified youth, who are at higher smoking risk.The evaluation uses a randomized treatment-control design with 15 campaign-targeted treatment and 15 control markets. We conducted surveys among 12- to 17-year-olds before campaign launch and at approximately 6-month intervals. Analyses explore treatment-control differences in Fresh Empire brand and video advertisement awareness at individual survey rounds and over time and perceived effectiveness of advertisements.Awareness of the Fresh Empire brand was higher among youth in treatment than control markets following campaign launch (ps.01). Awareness of the Fresh Empire brand increased more in treatment than control over time (adjusted odds ratio = 3.26, 95% confidence interval = 1.90-5.58). At follow-ups 1 and 3, youth in treatment (vs. control) were more likely to report high and less likely to report low awareness of video advertisements (ps.05). There were no treatment-control differences in video awareness at follow-up 2 (not significant). Fresh Empire video advertisements had perceived effectiveness scores ranging from 3.66 to 4.11 (1-5 scale) across three survey rounds.Among the campaign audience of Hip Hop-identified youth, awareness of the Fresh Empire campaign was higher in treatment than control markets at individual survey rounds, and increases in campaign awareness were greater in treatment than control markets over time. Campaign advertisements also elicited positive audience reactions. Findings suggest that heavily digital campaigns may take longer to achieve Centers for Disease Control and Prevention-recommended 75% quarterly awareness.

A comprehensive comparison between Bi$_{25}$FeO$_{40}$-reduced graphene oxide(rGO) nanocomposite and BiFeO$_{3}$-rGO nanocomposite has been performed to investigate their photocatalytic abilities in degradation of Rhodamine B dye and generation of hydrogen by water-splitting. The hydrothermal technique adapted for synthesis of the nanocomposites provides a versatile temperature-controlled phase selection between perovskite BiFeO$_{3}$ and sillenite Bi$_{25}$FeO$_{40}$. Both perovskite and sillenite structured nanocomposites are stable and exhibit considerably higher photocatalytic ability over pure BiFeO$_{3}$ nanoparticles and commercially available Degussa P25 titania. Notably, Bi$_{25}$FeO$_{40}$- rGO nanocomposite has demonstrated superior photocatalytic ability and stability under visible light irradiation than that of BiFeO$_{3}$-rGO nanocomposite. The possible mechanism behind the superior photocatalytic performance of Bi$_{25}$FeO$_{40}$-rGO nanocomposite has been critically discussed., Comment: 13 pages, 6 figures

This investigation explores the utilization of semiconductor zinc oxide (ZnO) based nanocomposite in decolorization of textile dyes. The structural, morphological and optical characteristics of semiconductor ZnO nanoparticles fabricated by hydrothermal process are scrutinized thoroughly and maneuvered with reduced graphene oxide (rGO) to yield superior properties and consequent preferable performance. The modification of the properties of zinc oxide nanoparticles by fabrication of a nanocomposite with an efficient electron acceptor like reduced graphene oxide results in excellent catalytic characteristics. The photocatalytic activity of the nanocomposite is carried out by photodegradation of Rhodamine B (a toxic colorant used in textile and medical industry) in aqueous solution under solar light irradiation. The synthesized nanocomposite along with the prepared zinc oxide nanoparticles are characterized by X-ray Diffraction (XRD), Field Emission Scanning Electron Microscope (FESEM), Energy Dispersive X-ray (EDX), and Ultraviolet-Visible (UV-Vis) spectroscopy.This investigation explores the utilization of semiconductor zinc oxide (ZnO) based nanocomposite in decolorization of textile dyes. The structural, morphological and optical characteristics of semiconductor ZnO nanoparticles fabricated by hydrothermal process are scrutinized thoroughly and maneuvered with reduced graphene oxide (rGO) to yield superior properties and consequent preferable performance. The modification of the properties of zinc oxide nanoparticles by fabrication of a nanocomposite with an efficient electron acceptor like reduced graphene oxide results in excellent catalytic characteristics. The photocatalytic activity of the nanocomposite is carried out by photodegradation of Rhodamine B (a toxic colorant used in textile and medical industry) in aqueous solution under solar light irradiation. The synthesized nanocomposite along with the prepared zinc oxide nanoparticles are characterized by X-ray Diffraction (XRD), Field Emission Scanning Electron Microscope (FESEM), Energy Dispersive X-ra...

This study analyzes the Stop and Frisk policy in New York City to see if there is any evidence of racial profiling in force used by police officers. The study uses a logit model to estimate the probability of having force used on an individual conditional on being stopped. The probability of having force used on blacks and Hispanics is higher. A model specification with an interaction term between race of the suspect and crime rate of the precinct where the individual stopped further suggests that the difference in probability of force between blacks, Hispanics and whites is highest in low crime rate precincts. For precincts with higher crime rates the difference in probability between blacks, Hispanic and whites is lower.