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Depressive symptoms are highly prevalent in nursing home (NH) residents. The relationship between depressive symptoms and everyday competence in terms of basic (BaCo) and expanded everyday competence (ExCo; see Baltes et al., 2001) in the NH setting is, however, not clear. Applying Lewinsohn's depression model, we examined how residents’ BaCo and ExCo relate to their depressive symptoms. Furthermore, we investigated the mediating role of perceived control.
Cross-sectional data from 196 residents (Mage = 83.7 years, SD = 9.4 years) of two German NHs were analyzed. Study variables were assessed by the Geriatric Depression Scale-Residential (GDS-12R), maximal gait speed (BaCo), proxy ratings of residents’ in-home activity participation, and self-initiated social contact done by staff (ExCo). Structural equation modeling (SEM) was used and a simulation study was included to determine power and potential estimation bias.
At the descriptive level, one quarter of the residents showed symptoms of depression according to the GDS-12R cut-off criterion. Residents’ BaCo and ExCo were independently and equally strongly associated with their depressive symptoms in the SEM analysis. These findings were affected neither by cognitive impairment, sex, nor age. Perceived control mediated between BaCo but not ExCo and depressive symptoms.
Future research needs to follow the connection between residents’ everyday competence and their depressive symptoms longitudinally to better understand the underlying mechanisms.
Broiler stunning is conducted to produce a rapid onset of insensibility prior to slaughter. Though most broiler plants use electrical stunning applications, gas stunning, and low-atmosphere pressure stunning are also available for commercial applications. All three of these stunning methods are able to meet animal welfare requirements and produce meat with acceptable quality. However, each method differs in their mechanisms of stunning, rigor mortis patterns, and physical meat characteristics. In addition, gas stunning and low-atmosphere pressure stunning have received interest over the past decade as part of an effort to further improve animal welfare. Researchers have reported that gas and low-atmosphere pressure stunning both have potential advantages over electrical stunning with respect to broiler welfare and deboning time, which has been attributed to shackling post-stunning. This review paper will focus on these three stunning methods and their impact on animal welfare, physiology, rigor mortis patterns, carcass characteristics, and meat quality.
We examined reported outbreaks of foodborne shigellosis in the USA from 1998 to 2008 and summarized demographic and epidemiological characteristics of 120 confirmed outbreaks resulting in 6208 illnesses. Most reported foodborne shigellosis outbreaks (n = 70, 58%) and outbreak-associated illnesses (n = 3383, 54%) were restaurant-associated. The largest outbreaks were associated with commercially prepared foods distributed in multiple states and foods prepared in institutional settings. Foods commonly consumed raw were implicated in 29 (24%) outbreaks and infected food handlers in 28 (23%) outbreaks. Most outbreaks (n = 86, 72%) were caused by Shigella sonnei. Targeted efforts to reduce contamination during food handling at multiple points in the food processing and distribution system, including food preparation in restaurants and institutional settings, could prevent many foodborne disease outbreaks and outbreak-related illnesses including those due to Shigella.
Sintered compacts of magnetically aligned single-crystal particles have been studied by x-ray, microscopy, and magnetic measurements. Though significant alignment and very anisotropie magnetic hysteresis were obtained, the magnitude of the hysteresis indicates, through the critical state model, that the bulk critical current density remains low.
The time and temperature dependent mechanisms underlying the relaxation of thermally induced stresses in Al-films on quartz substrates have been investigated for film thicknesses in the range between 0.4 and 4.2 μm. Film stresses were determined by a high resolution capacitive technique from the bending displacement of the specimens. By employing a lamp furnace heating rates of 10°C/sec could be achieved. This test equipment allowed the investigation of thermally induced film stresses between room temperature and 450°C and in the time range between 10 sec and several hours. Similar temperature programms were run in situ in a scanning electron microscope in order to observe the concommitant changes of the surface morphologies.
The experiments show that a major fraction of 50 to 70% of the thermal stress recovers instantaneously by plastic flow. This defines a yield stress for the Al-films which is found to be inversely proportional to the film thickness and to vary linearly with temperature. The magnitude of the yield strength under tension is larger by a factor 1.7 compared to that under compression.
The relationship between the supramolecular conformational structure of assembled chromophores and their susceptibility to electric field poling is of interest for maximizing the bulk alignment achievable in an electro-optic material. We have employed solution phase dielectric constant measurements to investigate possible enhancements in dipolar susceptibility as a function of connectivity and state of aggregation in rationally synthesized chromophore assemblies, including conformationally defined head-to-tail oligomers. On the other hand, conformationally unrestricted, highly dipolar azo dyes behave as relatively isolated molecules even when present in supersaturated solutions and in close proximity on polymer chains.
Molecular second-order nonlinear optical susceptibilities (β) based on EFISH measurements in dimethylsulfoxide of selected donor-acceptor substituted organic compounds are reported. Enhanced values were noted for compounds containing highly ionizable substituents. Compounds possessing the highest susceptibilities were dissolved in polymer films and electric-field poled, leading to corresponding enhancements in the nonlinear optical coefficients. The data are consistent with molecular and thermodynamic models.
We present results of studies of orientational order of Langmuir-Blodgett monolayer and multilayer films based on second harmonic generation and linear absorption measurements. Two new compounds, a tricyanovinyl aniline and a tricyanovinyl azo dye, both possessing large second order molecular susceptibilities have been synthesized and transferred as monolayers from the air-water interface to solid substrates using the Langmuir-Blodgett technique. The azo dye is a superior Langmuir-Blodgett material, forming films which are chemically and structurally stable. Multilayers of this compound show an enhancement in polar orientational order with thickness, as observed in the dependence of the second harmonic polarization components on number of layers.
Achieving spatially uniform and hierarchically structured microstructures during the shape-forming of colloidal ceramics depends largely on (i) the magnitude of the effective stresses (i.e., stresses that are supported by the particulate network) and (ii) plastic properties, which in turn are significantly altered by processing parameters affecting interparticle friction and adhesion. To quantify the effects of processing parameters on consolidation, we present a novel approach for analyzing sediments by gamma-ray densitometry and a fluid mechanics model. This method enables us to correlate processing parameters with spatial variations of the packing density and the local effective stress. These correlations are difficult to achieve by traditional techniques (e.g., rheometry, sedimentation kinetics modeling, soil mechanics tests), especially for the low stresses (< 1000 Pa) that are typically encountered in sediments. Aside from being destructive to samples, these techniques also tend to measure volume-averaged properties, and as a result they usually fall short of describing localized consolidation phenomena.
The title oligomers have been incorporated in Zr-based layers on quartz substrates. Absorbance and emission spectra and fluorescence decays have been measured on these films and compared with data from solutions, powders, and PPV. The samples may be divided into those with “liquid-like” behavior and “solid-like” behavior; the latter is characterized by blue-shifted absorbance, red-shifted emission, and more complex decay dynamics than the former. By these criteria, the layers and PPV itself are decidedly “solid-like’.
This paper presents a study of the effects of electron beam (e-beam) exposure on the chemical and physical properties of FLARE™ 1.0X, a non-fluorinated member of the FLARE™ family of poly(arylene ether) dielectric coatings. Spin-coated films of this poly(arylene ether) were cured by large-area e-beam exposure, as well as by conventional thermal processing. Neither swelling nor dissolution was observed for the e-beam cured films after immersion in N-methylpyrrolidone (NMP) at 90 °C for 1 hour. The glass transition temperature (Tg) for films cured with a low e-beam dose is slightly higher than, or nearly the same as, the (Tg) for thermally-cured films (∼ 270 °C). However, the Tg for films cured with a high e-beam dose exceeds 400 °C. Dielectric constants of e-beam cured films and thermally cured films are nearly the same. FTIR spectra of FLARE™ films obtained before and after e-beam exposure suggest that e-beam curing does not induce any significant change in the chemical structure. Increased solvent resistance, higher Tg, and low dielectric constant are properties that make this e-beam cured poly(arylene ether) film an excellent candidate for interlevel dielectric integration processes.
Many organic-based optical components are based on refractive index modulation or contrast as the origin of their activity. These range from passive components such as waveguides, to active components that include electro-optic switches, photorefractive information processing elements, and holographic storage media. Common to the materials used in these applications is the need for charge and/or molecular migration in their preparation or utilization. This paper focuses on some of these migration effects, with special attention paid to a new class of photopolymers being designed for high density digital holographic data storage applications.
Eudialyte-group minerals (EGM) represent the most important index minerals of persodic agpaitic systems. Results are presented here of a combined EPMA, Mössbauer spectroscopy and LA-ICP-MS study and EGM which crystallized in various fractionation stages from different parental melts and mineral assemblages in silica over- and undersaturated systems are compared. Compositional variability is closely related to texture, allowing for reconstruction of locally acting magmatic to hydrothermal processes. Early-magmatic EGM are invariably dominated by Fe whereas hydrothermal EGM can be virtually Fe-free and form pure Mn end-members. Hence the Mn/Fe ratio is the most suitable fractionation indicator, although crystal chemistry effects and co-crystallizing phases play a secondary role in the incorporation of Fe and Mn into EGM. Mössbauer spectroscopy of EGM from three selected occurrences indicates the Fe3+/ΣFe ratio to be governed by the hydration state of EGM rather than by the oxygen fugacity of the coexisting melt. Negative Eu anomalies are restricted to EGM that crystallized from alkali basaltic parental melts while EGM from nephelinitic parental melts invariably lack negative Eu anomalies. Even after extensive differentiation intervals, EGM reflect properties of their respective parental melts and the fractionation of plagioclase and other minerals such as Fe-Ti oxides, amphibole and sulphides.
Indentation tests were performed to assess the influence of compositional changes on the mechanical properties of several half-Heusler compounds with the general composition Zr0.5Hf0.5Co1-xIrxSb0.99Sn0.01 (x=0.0,0.1,0.3,0.5,0.7). These samples were synthesized by high temperature solid-state reactions and were consolidated by hot-pressing. Indentation measurements were obtained using both microhardness testing (Vickers) and depth-sensing nanoindentation. These measurements were used to determine the microhardness and the elastic modulus of each half-Heusler compound. The Vickers hardness values were found to range between 876 and 964. A slight increase in hardness was observed with the addition of iridium. The elastic stiffness values ranged from 229 GPa to 246 GPa. Here, a slight decrease in stiffness was observed with the addition of iridium.
A perfect 2D porous alumina photonic crystal with 500 nm interpore distance was fabricated on an area of 4 cm2 via imprint methods and subsequent electrochemical anodization. A 4” imprint stamp consisting of a convex pyramid array was obtained by modern VLSI processing using DUV-lithography, anisotropic etching, LPCVD Si3N4 deposition and wafer bonding. The optical properties of the porous alumina photonic crystal were measured with an infrared microscope in Г-M direction. For both polarizations, a bandgap is observed at around 1 μm for r/a = 0.42. A reflectivity of almost unity for E-polarization in the region of the bandgap is a sign of the high quality of the structure, indicating almost no scattering losses. These experimental results could be correlated very well to the bandstructure as well as reflectivity calculations assuming a dielectric constant of å = 2.0 for the anodized alumina.
Extended 3D photonic crystals based on macroporous silicon are prepared by applying a periodic variation of the illumination during photoelectrochemical etching. If the lateral pore arrangement is 2D hexagonal, the resulting structure exhibits a simple 3D hexagonal symmetry. The dispersion relation along the pore axis is investigated by optical transmission measurements. Photonic band gaps originating from the pore diameter modulation are observed and the group velocities of the photonic bands are determined by analyzing the Fabry-Perot resonances. Furthermore, angular resolved transmission measurements show a spectral region of omnidirectional total reflectivity.
Greenhouse experiments were conducted to determine whether multiple applications of glyphosate and time of glyphosate application with regard to the crop's growth stage had a significant effect on the growth and development of glyphosate-resistant canola. Glyphosate was applied as single applications at the two-, four-, or six-leaf stage of canola; as sequential double applications at the two- and four-, two- and six-, and four- and six-leaf stages of canola; and as a triple application at all three stages. Of the plant growth parameters measured, single applications of glyphosate resulted in significant reductions to stem weight and shoot weight compared with nontreated plants, and multiple applications of glyphosate caused significant reductions to leaf area, leaf weight, stem weight, and shoot weight. Single applications of glyphosate were less injurious to glyphosate-resistant canola compared with multiple applications, and canola growth parameter reductions were greatest after earlier glyphosate applications.
“There is really only one Game, the Game in which each of us is a player acting out his role. The Game is Leela, the universal play of cosmic energy.” Thus begins Harish Johari in Leela: the game of selfknowledge, a serious commentary and religious interpretation of the Hindu board game Leela. Leela is essentially the game Snakes and Ladders, which in the U.S. is the popular children’s game of snakes and ladders, England’s famous indoor sport,” for 50ø in 1943 by the Milton Bradley Company of Springfield, Massachusetts. This game is really a 101 state absorbing Markov chain, which is amenable to mathematical as well as moral analysis. In what follows we investigate only the mathematical side of this diversion, specifically the expected playing time.
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