Mosaic models for textures

This paper deals with a class of image models based on random geometric processes. Theoretical and empirical results on properties of patterns generated using these models are summarized. These properties can be used as aids in fitting the models to images.     

A model for the trap-assisted tunneling mechanism in diffused n-pand implanted n+-p HgCdTe photodiodes

A theoretical model for the trap-assisted tunneling process in diffused n-on-p and implanted n⁺-on-p HgCdTe photodiodes is presented. The model describes the connection between the leakage current associated with the traps and the trap characteristics: concentration, energy level, and capture cross sections. It was observed that the above two types of diodes differ in the voltage dependence of the trap-assisted tunneling current and dynamic resistance. The model takes this difference into account and offers an explanation of the phenomenon. The good fit between measured and calculated DC characteristics of the photodiodes (for medium and high reverse bias and for temperatures from 65 to 140 K) supports the validity of the model     

Prediction of sensory quality by near infrared reflectance analysis of frozen and freeze dried green peas (Pisum sativum)

Frozen, green peas (Pisum sativum L ) of different varieties and different levels of maturity were evaluated by sensory analysis using a panel of ten trained judges. Two texture variables (hardness and mealiness) and four flavour variables (pea flavour, sweetness, fruity flavour, off flavour) were considered. Near infiared reflectance ( N I R ) analysis was performed with the same material, on both the fiozen and fieeze dried peas. The N I R instrument was calibrated to predict the sensory variables using the multivariate analytical method of principal component regression. Tenderometer readings of the same peas were also calibrated to predict the sensory variables. N I R analysis on the fieeze dried peas showed relative ability of prediction (RAP) values for the sensory variables which were higher than those for the tenderometer readings. The sensory attributes pea flavour and hardness were predicted with higher RAP values by tenderometer readings than by N I R analysis on fiozen peas. For the rest of the attributes, N I R analysis on fiozen peas gave higher RAP values than tenderometer readings. N I R generally gave high RAP values, and this tentative study suggests that N I R analysis could be a useful tool in instrumentally assessing the quality of frozen peas.     

Kristallin-flüssige 1,3,4-Thiadiazole. II [1]. 1,3,4-Thiadiazole mit Cyclohexanstrukturfragmenten

Liquid Crystalline 1,3,4-Thiadiazoles. II. 1,3,4-Thiadiazoles with Cyclohexanefragments Preparation and liquid crystalline properties of disubstituted 1,3,4-thiadiazoles (1 and 2) are described. The mesomorphic behaviour of the title compounds is compared with their benzoate analogues. The dielectric anisotropy of these compounds is negative.     

Symbolic pixel labeling for curvilinear feature detection

This paper describes a method of detecting thin curvilinear features in an image based on a detailed analysis of the local gray level patterns at each pixel. This allows operations such as thinning and gap filling to be based on more accurate information.     

Investigation of Polyimidesiloxanes for Use as Adhesives by Electron Spectroscopy for Chemical Analysis

Angle-dependent electron spectroscopy for chemical analysis (ESCA) was used to examine the air facing surface (20–100 Å thick) composition of polyimidesiloxanes with different processing variations, and of varying polydimethylsiloxane (PDMS) content and block length (number of PDMS repeat unit varies from 1 to 9). Polyimide was clearly detected (due to the nitrogen content) in the 20–100 Å surface regions. This shows that a small amount of PDMS and short PDMS segment lengths in polyimidesiloxanes give a surface region with both PDMS and polyimide present. The surface composition, particularly that in the ca. 100 Å region, was correlated to the peel strength of polyimidesiloxane melt pressed to a metal substrate. Our results suggest that both PDMS and polyimide are essential components to rendering a needed peel strength. PDMS, having a good diffusive ability, readily reaches the substrate upon being pressed, achieving intimate contact, while imide groups interact with the substrate, presumably through chemical bonding; these two factors act synergistically to result in a high peel strength. In addition, the interaction mechanism and the failure mechanism involved in bonding polyimidesiloxane and metal substrate were also elucidated based on the ESCA results.     

Intraovarian actions of oestrogen

Oestrogen regulates several hypothalamic and pituitary hormones, which in turn control ovarian functions. Oestrogen and its metabolites, such as catecholoestrogens, also have direct effects within the ovary. This review examines the roles of oestrogen in regulating ovarian folliculogenesis, ovulation and corpus luteum formation. Oestrogen promotes follicular development, which culminates in ovulation, by potentiating follicular development, granulosa cell expression of gonadotrophin receptors, steroidogenesis, and gap junction formation by granulosa cells, and by inhibiting granulosa cell apoptosis. In addition, oestrogen may be needed for corpus luteum formation and maintenance. Studies on mutant mice that either lack one or both of the known oestrogen receptors or are unable to synthesize oestrogen support some but not all of these prior inferences of the roles of oestrogen within the ovary. Although these transgenic mice have proved useful in determining some of the intraovarian actions of oestrogen, they present confounding problems, including hormonal imbalances, that hinder interpretation. Transgenic mice with conditional or tissue-directed mutations in their oestrogen receptors are needed to dissect the ovarian actions of oestrogen further. In addition, microarray technologies, combined with specific hormone treatment regimens are likely to provide an attractive, alternative approach to using mutant mice in clarifying the direct actions of oestrogen in the ovaries of other species.     

The anatomy of odour wheels for odours of drinking water, wastewater, compost and the urban environment.

In the drinking water and air pollution fields, odour quality characterisation and intensity of each odour characteristic needs to be developed to evaluate the causes of the odours present. Drinking water quality characterisation has matured to the point where an "odour wheel" is described and the primary chemicals producing the odour are known and therefore a potential treatment can be defined from the odours reported. Sufficient understanding of the types of odorous compounds that can arise from wastewater and compost treatment processes and odours in the urban environment are starting to emerge. This article presents the anatomy of the odour wheels. It is hoped that the foundation of odour wheels will evolve as odour quality data are reported and linked with chemical causation. The compost and urban odour wheels are presented in print for the first time.