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Regular HIV testing is an essential component of the HIV prevention and care cascade. Sexual minority males (SMM) account for most new HIV infections in the US and testing rates among SMM vary substantially across the lifespan. Research has largely overlooked the developmental context of HIV testing. The current study compared correlates of HIV testing among adolescents (aged 13-17; n = 1,641), emerging adults (aged 18-29; n = 50,483), early adults (aged 30-39; n = 25,830), middle adults (aged 40-64; n = 25,326), and late adults (65 and older; n = 1,452) who were recruited online. Overall, HIV testing rates were lowest among adolescent SMM. Having condomless anal sex in the past 3-months was a consistentpredictor of HIV testing across all age cohorts.The association between relationship status and frequency of HIV testing varied across ages. Being in a non-monogamous relationship (versus single) was associated with more frequent HIV testing among adolescent and emerging adult SMM, while being in a monogamous relationship (versus single) was associated with lower odds of HIV testing among early, middle, and late adults., Author(s): Trey V. Dellucci [sup.1] [sup.2] , S. Scott Jones [sup.1] , Christel Adhemar [sup.1] , Sarah W. Feldstein Ewing [sup.3] , Travis I. Lovejoy [sup.4] [sup.5] , Tyrel J. [...]

Background: Several studies have evaluated whether the distribution of natural environments differs between marginalized and privileged neighborhoods. However, most studies restricted their analyses to a single or handful of cities and used different natural environment measures. Objectives: We evaluated whether natural environments are inequitably distributed based on socioeconomic status (SES) and race/ethnicity in the contiguous United States. Methods: We obtained SES and race/ethnicity data (2015-2019) for all U.S. Census tracts. For each tract, we calculated the Normalized Different Vegetation Index (NDVI) for 2020, NatureScore (a proprietary measure of the quantity and quality of natural elements) for 2019, park cover for 2020, and blue space for 1984-2018. We used generalized additive models with adjustment for potential confounders and spatial autocorrelation to evaluate associations of SES and race/ethnicity with NDVI, NatureScore, park cover, and odds of containing blue space in all tracts (n = 71,532) and in urban tracts (n = 45,338). To compare effect estimates, we standardized NDVI, NatureScore, and park cover so that beta coefficients presented a percentage increase or decrease of the standard deviation (SD). Results: Tracts with higher SES had higher NDVI, NatureScore, park cover, and odds of containing blue space. For example, urban tracts in the highest median household income quintile had higher NDVI [44.8% of the SD (95% CI: 42.8, 46.8)] and park cover [16.2% of the SD (95% CI: 13.5, 19.0)] compared with urban tracts in the lowest median household income quintile. Across all tracts, a lower percentage of non- Hispanic White individuals and a higher percentage of Hispanic individuals were associated with lower NDVI and NatureScore. In urban tracts, we observed weak positive associations between percentage non-Hispanic Black and NDVI, NatureScore, and park cover; we did not find any clear associations for percentage Hispanics. Discussion: Multiple facets of the natural environment are inequitably distributed in the contiguous United States. https://doi.org/10.1289/EHP11164, Introduction Of all high- and middle-income countries, the United States has among the highest income-related disparities in self-reported health and health care measures. (1) Health disparities have been attributed to [...]

We present a simple chip-based refractometer with a central organic light-emitting diode (OLED) light source and two opposed organic photovoltaic (OPV) detectors on an internal reflection element (IRE) substrate, creating a true dual-beam sensor platform. For first-generation platforms, we demonstrate the use of a single heterojunction OLED based on electroluminescence from an [Alq.sub.3]/TPD heterojunction (tris-(8-hydroxyquinoline)-aluminum/N,N'-bis(3-methylphenyl)-N,N'-diphenyl- benzidine) and light detection with planar heterojunction pentacene/[C.sub.60] OPVs. The sensor utilizes the considerable fraction of emitted light from conventional thin-film OLEDs that is coupled into guided modes in the IRE, instead of into the forward (display) direction. A ray-optics description is used to describe light throughput and efficiency-limiting factors for light coupling from the OLED into the substrate modes, light traversing through the IRE substrate, and light coupling into the OPV detectors. The arrangement of the OLED at the center of the chip provides for two sensing regions: a 'sample' channel and a 'reference' channel, with detection of light by independent OPV detectors. This configuration allows for normalization of the sensor response against fluctuations in OLED light output, stability, and local fluctuations (temperature) that might influence sensor response. The dual-beam configuration permits significantly enhanced sensitivity to refractive index changes, relative to single-beam protocols, and is easily integrated into a field-portable instrumentation package. Changes in refractive index ([DELTA]RI) between [10.sup.-2] and [10.sup.-3] RI units could be detected for single beam operation, with sensitivity increased to [DELTA]RI [approximately] [10.sup.-4] RI units when the dual-beam configuration is employed. 10.1021/ac9026109

A new multimodel computational framework for optimal control of aeroacoustic noise is presented using a nearfield compressible Navier-Stokes solver coupled with a far-field linearized Euler solver, both based on a discontinuous Galerkin formulation. In this approach, the coupling of near- and far-field domains is achieved by weakly enforcing continuity of normal fluxes across a coupling surface that encloses all nonlinearities and noise sources. For optimal control, gradient information is obtained by the solution of an appropriate adjoint problem that involves the propagation of adjoint information from the far field to the near field. This computational framework is applied to study optimal boundary control of blade-vortex interaction, which is a significant noise source for helicopters on approach to landing. In the prototype problem presented here, the noise propagated toward the ground is reduced by 12 dB, demonstrating the potential of an optimization-based approach to blade-vortexinteraction noise control.

I. INTRODUCTION II. BACKGROUND A. The Patent Act and Its Consideration of National Security-Affecting Patents B. International Agreements Affecting the Transferability of Intellectual Property Rights 1. The Patent Cooperation Treaty [...]

The structural and functional properties of ultrathin (< 5 nm) poly(aniline) (PANI) films deposited on indium tin oxide (ITO) have been investigated using electrochemical and attenuated total reflection (ATR) spectroscopy methods. Layer-by-layer (LbL) self-assembly was used to form films composed of one and two bilayers of PANI and poly(acrylic acid) (PAA), as well as single PANI layers of approximately monolayer thickness. PANI deposited on an ITO electrode is electroactive at neutral pH, both with and without codeposition of an acid dopant such as PAA. In the absence of PAA, it is hypothesized that the acidic surface groups on ITO can function as the counterion. The pH response of PANI single layer, [(PANI/PAA).sub.1], and [(PANI/PAA).sub.2] films was examined using both potentiometry and ATR spectroscopy. Near-Nernstian potentiometric responses over pH 3-9 were observed for all three types of films, consistent with the weak acid--base behavior expected of polymers assembled in a LbL film. The ATR spectral sensitivity to pH increases as the number of layers in the film increases, with the highest sensitivity achieved by monitoring the absorbance at 800 nm (predominately due to the emeraldine salt form) of [(PANI/ PAA).sub.2] films. Codeposition of PANI and PAA appears to produce a wide distribution of strengths of acidic and basic sites in the film and thus a large linear dynamic range, up to six pH units. The water contact angle of [(PANI/PAA).sub.2] is ~16[degrees], which is considerably more hydrophilic than either the PANI single layer or [(PANI/ PAA).sub.1] films (~40[degrees]). This film is shown to be a suitable substrate for deposition of a planar supported phospholipid bilayer. The supported membrane is highly impermeable to protons, which makes this architecture useful for monitoring transmembrane charge transport.

The study describes a method to determine the anisotropic optical and surface coverage of molecular films using polarized attempted total reflectance (ATR) absorbance measurements. Anisotropic values of the imaginary part of the refractive index (k) allow for the determination of the surface coverage and one order parameter of the film.

The goal of this paper is to provide a perspective on the current status and future directions for active flow-control technology with particular emphasis on oscillatory control. This is not a comprehensive review of the literature; rather, certain issues that are often neglected in studies are highlighted showing their importance or impact on the reported observations and targeted outcomes. Feasible routes using flow instability as an efficiency enhancement tool are discussed as an emerging means to explain the physical phenomena of active flow-control and as a tool for control law design and development. Traditional and more recent theoretical approaches to control design are discussed and recommendations are made relevant to numerical complications on the route to design oscillatory flow-control systems. A generic flow control process is put forward and illustrated using experimental examples.

The capabilities of the variational multiscale (VMS) method are explored in the context of turbulence control by applying VMS to the simulation of a simple opposition-control strategy for turbulent channel flow with the results compared to prior direct numerical simulations and large-eddy simulations based on the dynamic subgrid-scale model. In all cases, the VMS method is found to be more efficient and more accurate than the dynamic model, and the simplicity, accuracy, and generality of VMS makes it particularly attractive for turbulence control investigations.

A technique to determine the angular orientation of a molecular assembly bound to the surface of a planar optical waveguide of arbitrary structure is described. The approach is based on measuring the absorption dichroic ratio by using the waveguide evanescent fields with orthogonal polarizations (TE, TM) and the same mode order to probe two molecular assemblies, (i) a reference sample composed of an isotrepic orientation distribution of dipoles and (ii) a sample of interest. The isotropic sample is used to characterize the waveguide structure, which then allows the orientation parameters of a molecular assembly under investigation to be determined from a measured dichroic ratio. The method developed here is particularly important for applications in gradient-index and multilayer planar waveguide platforms because in those cases the extension of previously reported approaches would require a full experimental characterization of the guiding structure, which would be problematic and may yield inaccurate results. OCIS codes: 240.6490, 240.6690, 130.2790, 130.3120.

According to the family values that characterized the cultures in which Jesus of Nazareth and Paul of Tarsus were socialized, the authority of fathers over their children was unquestioned and almost without limits. All children were taught that filial piety was essential to life; obedience was expected of even grown sons and daughters as long as their fathers were alive, including acquiescing to the marriages that fathers were expected to arrange to increase their family's honor. The historical Jesus undermined the authority of fathers in general and rejected the obligations of blood-family ties. Paul of Tarsus then sought to put into effect Jesus' strategy, including ignoring completely the authority of fathers when advising his readers regarding marriage, divorce, and celibacy. For both Jesus and Paul, rejecting patriarchal authority was the first step toward their creating a new kind of family: faith-related brothers and sisters--without a traditional father., Who should be called 'father'? What an odd question. Doesn't everyone in every culture grow up calling the male who begot them their linguistic equivalent of 'father'? In the world [...]

We consider the optimal boundary control of aeroacoustic noise, governed by the two-dimensional unsteady compressible Euler equations. The control is the time- and space-varying wall normal velocity on a subset of an otherwise solid wall. The objective functional to be minimized is a measure of acoustic amplitude. Optimal transpiration boundary control of aeroacoustic noise introduces challenges beyond those encountered in direct aeroacoustic simulations or in many other optimization problems governed by compressible Euler equations. One nontrivial issue that arises in the optimal control problem is the formulation and implementation of transpiration boundary conditions. Because suction and blowing on the boundary are allowed, portions of the boundary may change from inflow to outflow, or vice versa, and different numbers of boundary conditions must be imposed at inflow vs outflow boundaries. Another important issue is the derivation of adjoint equations, which are required to compute the gradient of the objective function with respect to the control. Among other things, this is influenced by the choice of boundary conditions for the compressible Euler equations. The approaches to meet these challenges are described and results presented for three model problems. These problems are designed to validate the transpiration boundary conditions and their implementation, study the accuracy of gradient computations, and assess the performance of the computed controls.

A single-mode, electroactive waveguiding platform capable of measuring spectroelectrochemical responses of surfaceadsorbed redox-active molecules over a broad spectral bandwidth has been created. This new planar waveguide spectrometer is a combination of the previously developed electroactive integrated optical waveguide (EA-IOW; Dunphy, D. R.; Mendes, S. B.; Saavedra, S. S.; Armstrong, N. R. Anal Chem. 1997, 69, 3086-3094) with a recently reported simplified approach to broadband coupling (Bradshaw, J. T.; Mendes, S. B.; Saavedra, S. S. Anal Chem. 2002, 74, 1751-1759). With the use of a commercially available prism as an incoupling element, the EA-IOW can now guide visible light from at least 500 to 700 nm, improving upon its previously demonstrated monochromatic nature. Coupling profiles of various laser lines along with transmission spectra of narrow band-pass filters at various potentials are used to demonstrate the optical characteristics of this broadband EA-IOW and to compare its response to that of a conventional transmission instrument. Assessment of spectral resolution, performed by measuring the fwhm of various laser lines, ranges from 0.6 to 0.8. To demonstrate the capabilities of this technology, we show the acquisition of absorbance spectra of two different adsorbates, cytochrome c and ferrocenedicarboxylic acid, as a function of applied potential. Subtleties in the redox chemistries of adsorbed molecules, which were difficult to monitor with a monochromatic waveguide, are readily apparent when using the broadband coupling scheme.

The quantitative measurements of the complex binding process between rgp 120 and GSL receptors at a model lipid membrane surface are detailed. The total internal reflection fluorescence (TIRF) results demonstrates that a carbohydrate on ceramide is a requirement for rgp120 recognition, and there is little dependence on the chemical composition of the fatty acid chain of ceramide in terms of both hydroxylation and fatty acid chain length.

Research demonstrates the synthesis and characterization of new class of porphyrazines containing 'polyetherol' groups, which bind metal ions and aid in pophyrazines solubility. Absorbance and fluorescence spectral data on the modified porphyrazines are provided and their usage in chemical sensors is discussed.

This article examines populations of abalones to assess ecological effects of three types of marine reserves in British Columbia, Canada. Research discussed includes the higher levels of abalones found in enforced reserves, as well as the benefits of larva dispersal to exploited areas from the reserves.

A water vapor sensor based on a combination of sol-gel processing and planar optical waveguide technologies has been developed. The indicator erythrosin B was entrapped in a thin sol-gel film (thickness [approximately] 100 nm) prepared from methyltriethoxysilane, dimethyldiethoxysilane, and tetraethoxysilane. This dye exhibits an increase in absorbance in the presence of liquid or gaseous water. The sol-gel layer containing the dye was deposited onto a sol-gel-derived, single-mode planar waveguide. Outcoupled light intensity measurements (at 514.5 nm) over a range of water vapor concentrations (in a nitrogen gas stream) yielded a response over a wide range of relative humidity (< 1 - [approximately] 70%) at room temperature. Response and reversal times were less than 1 min, which may make this sensor attractive for real-time monitoring applications.

Avidin and streptavidin are widely used tetrameric proteins, acting as binding mediators in many bioanalytical applications. There is much interest in the structure and bioactivity of multilayer films that contain such proteins. Molecular orientation in asymmetric protein bilayers on planar glass substrates has been investigated, with a multilayer architecture comprising a biotin capped phospholipid bilayer, streptavidin and yeast cytochrome c biotinylated at cysteine 102. Orientation distributions were almost identical, indicating that lateral interactions are not need to form macroscopically oriented protein films.

The 6A6B-bis-omicron-[p-(allyloxy)phenyl]-substituted beta-cyclodextrins were synthesized to determine the chromatographic properties of different cyclodextrin-oligosiloxane copolymeric phases. Analysis of two p-(allyloxy)phenyl]-heptakis(2,3-di-omicron-methyl)-beta-cyclodextrin indicated the presence of a self-inclusion complex in one of the compounds . Furthermore, the complexes are composed of seven glucose units with an unsymmetrical cylcodextrin cavity.

Highly sensitive spectroelectrochemistry of adsorbed films on ITO is demonstrated with the electroactive integrated optical waveguide (EA-IOW). The EA-IOW, a single-mode planar waveguide coated with an ITO layer, is [approximately][10.sup.4]-fold more sensitive to changes in absorbance occurring during electrochemical events versus a single-pass transmission spectroelectrochemical experiment, as demonstrated by reduction of surface-adsorbed methylene blue. Furthermore, the EA-IOW is selective to near-surface events, as it is relatively insensitive to absorbance by solutions of dissolved chromophores at < 1 mM. The EA-IOW is also used to monitor the formation of Prussian Blue during the reduction of ferricyanide, an event that is not easily followed using current-detected cyclic voltammetry, due to interfering faradaic and non-faradaic electrochemical events. The optical background of the EA-IOW is potential-dependent and is explained by ion diffusion into the ITO and by voltage-dependent changes in optical constants for the material. Finally, the high sensitivity of the EA-IOW (relative to other evanescent-field-based spectroelectrochemical techniques) is discussed in terms of its design.

The molecular orientation in hydrated cytochrome c (cty c) films produced by adsorption to substrates of varying surface chemistry was examined. Findings indicated that a macroscopically arranged film of adsorbed cyt c molecules is formed when a single, high-affinity type of noncovalent binding occurs between the surface of the protein and the substrate surface. For example, electrostatic absorption of the positively charged protein to the negatively charged head groups of a Langmuir-Blodgett film of arachidic acid produces a narrow orientation distribution.

The molecular orientation in films of yeast cytochrome c immobilized through disulfide bonding between cysteine 102 and the thiol tail groups of self-assembled monolayers (SAMs) coated on planar glass substrates was studied. Findings indicated that the molecular architecture does not produce a highly oriented protein film. A significant portion of the immobilized cytochrome c is nonspecifically absorbed to the SAM surface, which produces a relatively broad distribution of heme orientations.

The reagent 2,4-diemthoxybenzene-1,5-disulfonyl chloride was used to treat heptakis(2,3-di-O-methyl)-beta-cyclodextrin (1) to selectively activate 6A,6B-dihydroxy groups of unsubstituted beta-cyclodextrin. The treatment yielded 6A,6B-bissulfonate ester 2 in a 3% yield. The two isomer 6A,6B-bis-O-[p-(allylox)phenyl]-heptakis(2,3-di-O-methyl)-beta cyclodextrin (3) was produced when treatment product was reacted with sodium p-(allyloxy)phenoxide in DMF.

A novel sensor for gaseous iodine has been developed using a combination of sol-gel processing and planar integrated optical waveguiding technologies. The sensing principle is based on the detection of a charge transfer complex formed between iodine and phenyl groups that have been incorporated into a porous, methylated glass film. The glass film was prepared from siloxane precursors by the sol - gel method. Sensors were fabricated by coating the film over a single-mode planar waveguide. Light was coupled into and out of the laminate structure using integral grating couplers, and formation of the charge transfer complex was monitored as attenuated total reflection of the guided wave. The sensor exhibits a linear response to [I.sub.2] in the range of 100 ppb to 15 ppm with response and recovery times less than 15 s. The response is selective to 4 ppm iodine in the presence of 10 ppm chlorine and is stable for at least 3 months.

Home and favored teams are given an implied advantage in betting markets despite the equalizer effect of point spreads. A model formulated to test the efficiency of the point spread market in football shows that favored and home teams are favored against underdog and away teams. Although the home advantage is supported when the game is played on neutral site and the opposing teams are equally balanced, the study found that betting biases occur because the considerations are limited to the favored teams.

We report a general approach to the design of broadband waveguide couplers. A double-parallel grating assembly is used to cancel the first chromatic order, and a proper choice of prism glass and base angle is made to compensate for the second chromatic order. The technique was applied to a Corning glass 7059 waveguide, and a spectral bandwidth of 70 nm was measured by the use of two complementary procedures. Key words: Achromatic coupler, grating coupler, prism coupler, planar waveguide, integrated optics, surface spectroscopy.

COMMERCIAL BANKS have historically played a dominant role in the municipal securities market by owning more municipals than any other investor group. Until recently, they could borrow, invest the proceeds [...]

A new optical sensing platform based on a combination of planar waveguiding and sol-gel processing technologies is described. The sensing element consists of two, submicrometer thick glass layers supported on an optically thick glass substrate; both layers were fabricated using a sol-gel coating method. The lower layer is a densified glass that functions as a planar integrated optical waveguide (IOW). The upper layer is an undensified glass of lower index doped with an optical indicator that is immobilized, yet remains sterically accessible to analytes that diffuse into the pore network. Formation of a complex between the analyte and indicator is detected via attenuated total reflection (ATR) of light guided in the IOW. Feasibility was evaluated by constructing IOW-ATR sensors for [Pb.sup.2+] and pH, based on immobilized xylenol orange and bromocresol purple, respectively. The response of both sensors was sensitive and rapid, features that are difficult to achieve simultaneously in monolithic sol - gel glass sensors. In the IOW-ATR geometry, these features are realized simultaneously because the primary axes of light propagation and analyte diffusion are orthogonal. The overall approach is technically simple, inexpensive, and applicable to a wide variety of indicator chemistries.

Applications of planar integrated optical waveguide (IOW) technology to problems in surface spectroscopy and optical chemical sensing have been partly limited by the difficulty of producing high-quality glass IOWs. The fabrication of IOWs by the sol-gel method from methyltriethoxysilane and titanium tetrabutoxide precursors is described here. The physical, chemical, and optical properties of the films during and after high-temperature annealing were studied using a variety of analytical techniques. The results show that the catalyst used to accelerate the sol-gel reaction strongly influenced the optical quality of the IOW. HCI catalysis produced waveguides with propagation losses of 1 dB/cm, whereas in the case of Si[Cl.sub.4] catalysis, propagation losses were

The United States produces about 212 million tons of hazardous waste a year. There's a good chance that your company produces some of that waste, or did in the past, or has a subsidiary that does. Even if your company's only connection to hazardous waste is that it owns a plot of land that was once used as a dumping ground, you may find yourself facing liability under the Superfund Act of 1980. The authors examine the Act's relevance to managers today, including the potential for liability, direct and indirect costs, the impact on corporate balance sheets, and the threat to corporate officers of personal liability. They argue that, in fact, environmental issues are manageable, and that responsible and forward-thinking managers will assess their firm's potential liability and take steps immediately to minimize and prevent it. To help managers begin that process, they include a series of questions for managers to ask. (Reprinted by permission of the publisher.)