Obituary: Paul Fraisse (1911–1996).

Memorializes Paul Fraisse whose main areas of research were the perception of time and duration; perception of rhythms, and rhythms in behavior; aspects of language, in particular attempts to understand why naming an object takes more time than reading the name of the object; and memory for words and for pictures. From the 1940s through the 1970s, Fraisse explored different approaches to the psychology of time: chronobiology, psychophysics, the Piagetian approach to the acquisition of the notion of time, philosophical approaches, and the application of these viewpoints to the perception of rhythm in music and in poetry. Fraisse's long academic career was spent entirely in Paris, where he occupied many major positions and where he struggled to obtain an adequate place for psychology in the university and scientific sphere in France. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Object interactions in juvenile rats (Rattus norvegicus): Effects of different experiential histories.

Examined the spontaneous ways in which an individual rat gathers information about its environment and the extent to which this information-gathering strategy is modified by experience. 30 male rats of the Berkeley S? strain were placed at weaning in enriched, group-housed, or impoverished conditions. After 30 days, they were placed individually in a dimly illuminated arena with several objects and videotaped for 10-min periods on 2 successive days. Analysis of the videotaped records showed no significant differences among the groups in locomotion, investigation of the arena, defecation, grooming, or total amount of object contact, but it showed significant differences in behaviors used during interactions with objects. Ss from the enriched condition showed significantly more diversity of behavior related to those objects that were small enough to be moved, without intergroup differences in amount of object contact. These experience-dependent changes in strategies for exploration may have widespread functional consequences. The procedure for videotape analysis presented here may be useful in studying many problems of animal behavior. (14 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

The way it was: Remembering David Shakow.

Comments on the obituary for David Shakow (see record 2005-08120-013) and further eulogizes him for his dedication and accomplishments. The author focuses primarily on the twelve years during which Shakow worked at the Worcester State Hospital (WSH). (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Electromagnetic radiation from hot carriers in FET-devices

We report on the emission of light from si MOS and GaAs MES devices. Processes involving band-to-band transitions and a Bremsstrahlung-continuum below the band-gap are shown to exist. Spatially nonuniform emission from the MESFETs is observed. The GaAs results are compared with Monte Carlo simulations.     

Synthesis and application of submicrometer fluorescence sensing particles for lysosomal pH measurements in murine macrophages

Phagocytosis of bioparticles such as bacteria and viruses by macrophages is a critical component of the immune response against infections. In this paper we describe the synthesis of submicrometer fluorescent particles with pH sensing capability. The particles are used to measure the pH and to monitor the effect of chloroquine, an antimalarial drug, on the pH in the lysosome, the cellular organelle involved in the phagocytosis process. The synthesis of the pH sensing particles is realized by the covalent attachment of amine reactive forms of Oregon Green (pH sensitive dye) and Texas Red (pH insensitive dye) to the surface of amino-modified submicrometer polystyrene particles. The particles are absorbed by J774 Murine Macrophages through phagocytosis and directed to lysosomes. Despite the high lysosomal levels of digestive enzymes and acidity, the absorbed particles remain stable for 12 h in the cells when they are stored in a PBS buffer solution at pH 7.4. The pH dynamic range of the sensing particles is between pH 4.5 and 7 with a sensitivity of 0.1 pH units. Exposure of the cells to chloroquine increases the lysosomal pH from 4.8 to 6.5. The effect is concentration-dependent.     

Iron, thermoregulation, and metabolic rate

Iron plays an important role, not only in oxygen delivery to the tissues, but also as a cofactor with several enzymes involved in energy metabolism and thermoregulation. As a result, much research has been dedicated to understanding the ramifications of iron depletion and iron deficiency anemia on the physiological functions of these enzymes. There is evidence to suggest that iron depletion and iron deficiency anemia cause physiological changes in the body not only during exercise, but also under resting conditions. Both rat and human studies have produced results revealing elevated levels of norepinephrine in the blood and urine of iron-deficient anemic subjects. These studies also provide evidence to suggest that elevation in metabolic rate may ultimately lead to slower growth rates and lower body weights in iron-deficient anemic animals and humans. The focus of this review is on the effects of iron deficiency on metabolic rate and thermoregulation. Prior to this discussion, a brief background on iron is presented.