Superoxide Dismutase Activities in Senescing Apple Fruit (Malus domestica Borkh.)

Total superoxide dismutase (SOD:superoxide: superoxide oxidoreductase; EC 1.15.1.1) activity and individual activities of its three different metalloenzymes, CuZn-SOD, Fe-SOD, and Mn-SOD, were investigated during senescence of apples (Malus domestica Borkh.). Total SOD activity and relative activities of its three forms varied greatly among cultivars. Activities underwent considerable change during senescence of fruit, but changes were different among cultivars. Whether fruit senesced at 0°C or 20°C had little effect on SOD activities, and application of the antioxidant diphenylamine (DPA) did not alter activities. SOD activities increased with occurrence of the physiological disorder “senescent breakdown,” but did not increase with occurrence of the disorder “superficial scald.” In a given apple cultivar, changes in total SOD activity generally paralleled activities of the different SOD forms. Such activity may reflect changes affecting food and nutritive quality of the fruit.     

PLACES OF WORSHIP AND NEIGHBORHOOD STABILITY

ABSTRACT: Despite ongoing interest in religious group involvement in community development, only limited research has considered whether the mere existence of a place of worship can be linked to neighborhood well‐being. This exploratory study uses a cross‐sectional design to examine the relationships between the presence of churches in high‐poverty neighborhoods and specific measures of neighborhood stability. One‐way analysis of variance (ANOVA) and geographic information system (GIS) software were employed to compare measures of structural permanence, residential tenure, and property valuation from a sample of two types of church (freestanding and storefront) and non‐church areas or “clusters.” The findings provide limited support for the conclusion that storefront churches, while modest and often regarded as less architecturally significant, may be overlooked contributors to the sort of stable urban space where residential population is preserved and investment maintained.     

Evaluation of Time-Intensity Sensory Responses using a Personal Computer

A method is presented which utilizes a personal computer to measure time-intensity (T-I) sensory responses. The judge uses a game paddle which moves an “X” along a fixed scale appearing on the monitor screen to indicate the attribute intensity at each instant in time. A clicker device on the game paddle can be used to record the occurrence of events such as initial mouth entry and time of swallowing. Data acquisition is continuous with the data stored on discs. This technique has advantages over strip chart recorder methods. Disc storage allows rapid and efficient data analysis. Judges can perform the evaluations virtually unsupervised with only minimal training.     

Formation of a Gel from a Heated Emulsion of Alfalfa Leaf Protein and Peanut Oil

A new method was investigated for extracting the proteins from green leaves (alfalfa). An opaque white gel formed when an emulsion of chloroplast-free leaf tissue juice and peanut oil was heated for 10 min at 90°C. The proximate composition of this gel was 40% moisture, 2% protein, 57% fat, 0.2% ash, and <1% carbohydrate. SDS-PAGE analysis of the gel suggested that fraction 1 or ribulose bisphosphate carboxylase is the major protein component present. The apparent viscosity of the gel, 5,257 m Pa.sec, was less than one-tenth of mayonnaise.     

Fracture Induced in Al2O3 Bicrystals by Anisotropic Thermal Expansion

Bicrystals of Al₂O₃ were fabricated to study the effects of thermal expansion anisotropy on fracture in a model system containing one grain boundary. Fractures occurred perpendicular to the directions of maximum tensile stress in bicrystals with thermal expansion coefficient differences as low as 0.31×10⁻⁶⁰C⁻¹ and originated at the boundary, probably in areas of high residual stress associated with pores. Numerical stress analysis of two-dimensional model bicrystal configurations showed that stresses induced by thermal expansion anisotropy are maximal in a region localized along the bicrystal boundary.     

Dielectric and Structural Investigations of the System BaTiO3-BaHfO3

Dielectric measurements and X-ray diffraction studies were made in the system BaTiO₃-BaHfO₃ for polycrystalline specimens containing from 0 to 30 mole % BaHfO₃. The maximum in the dielectric constant for each composition in creased as the BaHfO₃ concentration was in creased to 16 mole % and then decreased with further BaHfO₃ additions. Room-temperature lattice constants and hysteresis loops were meas ured for all compositions. A partial solid-state phase diagram is suggested for the solid solution area of the system. The phase diagram and the dielectric behavior of the system up to 16 mole % BaHfO₃ are explained on the basis of Devonshire's thermodynamic theory. The ferroelectric-paraelectric transition in the composition containing 16 mole % BaHfO₃ was essentially of second order and occurred between a ferroelectric rhombohedral phase and a paraelectric cubic phase.     

Some circuit theory concepts revisited†

The concept of causality is introduced in a generalized form. Related system properties are then developed in an axiomatic manner. The unification of the development is illustrated through examples and discussions on related literature     

On the stability of a class of non-linear continuous systems†

A procedure to find the existence and domain of asymptotic stability for a class of systems described by a set of non-linear partial differential equations is presented in the context of semigroup theory.

No a priori bound is imposed on the non-linearity which is assumed to be a quad ratic (bilinear) or multilinear form.

The linearized system can be non-self-adjoint and need not be asymptotically stable equation by equation.

The solution of the stability problem is carried out. in two steps :

(a) the development of an L₂-like norm that bounds above the sup norm, a requirement to obtain a useful estimate of the non-linear term, and

(a)the computation of an estimate of the L₂-likc norm of the semigroup generated by the linearized system in terms of its usual L₂ norm.     

Simulation applied to the approximation of two-dimensional digital filters

Multi-stage Monte Carlo optimization is used to approximate two-dimensional digital filters taken from the literature. Most solution techniques revolve around the least-squares theory and practice. However with multi-stage one can use other measures of closeness or goodness of fit. This is done here and comparisons of the multi-stage results are made with other solution attempts.