Axisymmetric oscillations of a cupola-shaped shell

A spectral boundary problem on axisymmetric eigenoscillations of a cupola-shaped shell is considered with emphasis on small shell thickness. The problem deals with a singularly perturbed system of ordinary differential equations. The paper examines analytical properties of the solution and, based on that, constructs an appropriate functional basis for Ritz’ method. Employing this basis provides fast convergence in the C ³-metrics.     

Zur Beurteilung der Teigwaren

Ohne ZusammenfassungMitteilung aus dem Kgl. Hygienischen Institut zu Posen.     

Gentechnik an Tieren - Schwerpunkte der Entwicklungen und Anwendungen in der Tier-Biotechnologie

Numerous procedures of gene technology for animals have been developed internationally and with large research input. They are applied for different areas of the modern biotechnology. The use of biotechnical innovations has affected the economical conditions in animal breeding and the environmental loading by effects of animals. Moreover, limitations are considered posed by biological conditions and risk factors. The use of gene technology in animal needs evaluation based on ethical criteria as well as the consideration of public acceptance.     

Constructing desirable identities—Self-presentation in psychotherapy and daily life: Comment on Kelly (2000).

A. E. Kelly's (see record 2000-08364-001) thesis that psychotherapy clients benefit from withholding negative information is considered in flight of current social-psychological theory and research. Positive illusions about oneself are associated with indexes of mental health; this is consistent with treating therapy as positive identity development. Self-presentation can shape self-concept, even apart from the feedback that an audience might provide; the social construction of identity is a powerful process, suggesting that withholding negative and presenting only positive information is adaptive. However, evidence concerning the level of identification of one's actions suggests complexities in understanding ways clients might deal with disclosing negative information; the authors argue that the impact on self-concept is probably more complex than A. E. Kelly's characterization and that the implications are of a broader scope than indicated so far. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Functional recovery of respiratory behavior during axonal regeneration in snails (Lymnaea stagnalis) is experience dependent.

This study investigated the role of experience in recovery of pulmonary respiration during axonal regeneration in Lymnaea stagnalis. Pulmonary respiration occurs when snails break the water surface and open the lung orifice, the pneumostome. It was shown that axotomy of all the axons innervating the pneumostome and surrounding area prevents the occurrence of lung respiration in 69% of snails. In the remaining 31%, lung respiration persisted, indicating that peripheral components alone are capable of initiating pneumostome openings and closures. Five weeks postsurgery, all snails with previous nerve crushes showed opening of the pneumostome with normal latency after breaking the water surface. However, prevention of pulmonary respiration during the recovery period dramatically changed the recovered behavior. Thus, experience in pulmonary respiration during axonal regeneration plays a role in the recovery of this behavior. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Determination of site-specific D/H isotope ratios of glycerol from different sources by 2H-NMR spectroscopy

 A method was developed for the preparation of glycerol from wines and from naturally occuring lipids. In addition, the D/H isotopic ratios of glycerol from these sources was determined using site specific natural isotopic fractionation. Glycerol from four different sources was examined: glycerol isolated from vegetable oils and animal fats, glycerol obtained by chemical synthesis and glycerol which is a byproduct of the alcoholic fermentation of grape musts. Depending on the origin of the glycerol, different isotopic ratios were found; these can be used for the detection of adulterated food or as proof of the authenticity of a given product, such as wine. Received: 13 May 1998     

Carbon nanowalls deposited by inductively coupled plasma enhanced chemical vapor deposition using aluminum acetylacetonate as precursor

Well aligned carbon nanowalls, a few nanometers thick, were fabricated by continuous flow of aluminum acetylacetonate (Al(acac)₃) without a catalyst, and independent of substrate material. The nanowalls were grown on Si, and steel substrates using inductively coupled plasma-enhanced chemical vapor deposition. Deposition parameters like flow of argon gas and substrate temperature were correlated with the growth of carbon nanowalls. For a high flow of argon carrier gas, an increased amount of aluminum in the film and a reduced lateral size of the carbon walls were found. The aluminum is present inside the carbon nanowall matrix in the form of well crystallized nanosized Al₄C₃ precipitates.     

Eigenoscillations of a thin-walled azimuthally closed,axially open shell of revolution

This paper generalizes earlier authors’ results on the analytical approximation of the singularly perturbed boundary problem describing the eigenoscillations of a thin-walled axisymmetric shell. The asymptotic behavior of the eigenmodes at the clamped ends is studied, and a set of trial functions capturing this behavior is constructed to be used in the Ritz method. Illustrative numerical examples demonstrate a fast convergence so that the eigenmodes are accurately approximated in a uniform metric together with their second-, third-, and fourth-order derivatives. The numerical results are validated by comparing them with an asymptotic eigensolution and computations done by the ANSYS codes based on the finite-element method.     

Latent structure and factorial invariance of a neuropsychological test battery for the study of preclinical Alzheimer's disease.

Objective: To examine the latent structure of a test battery currently being used in a longitudinal study of asymptomatic middle-aged adults with a parental history of Alzheimer's disease (AD) and test the invariance of the factor solution across subgroups defined by selected demographic variables and known genetic risk factors for AD. Method: An exploratory factor analysis (EFA) and a sequence of confirmatory factor analyses (CFA) were conducted on 24 neuropsychological measures selected to provide a comprehensive estimate of cognitive abilities most likely to be affected in preclinical AD. Once the underlying latent model was defined and the structural validity established through model comparisons, a multigroup confirmatory factor analysis model was used to test for factorial invariance across groups. Results: The EFA solution revealed a factor structure consisting of five constructs: verbal ability, visuospatial ability, speed & executive function, working memory, and verbal learning & memory. The CFA models provided support for the hypothesized 5-factor structure. Results indicated factorial invariance of the model across all groups examined. Conclusions: Collectively, the results suggested a relatively strong psychometric basis for using the factor structure in clinical samples that match the characteristics of this cohort. This confirmed an invariant factor structure should prove useful in research aimed to detect the earliest cognitive signature of preclinical AD in similar middle aged cohorts. (PsycINFO Database Record (c) 2010 APA, all rights reserved)