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The ED50 of a strain of Serratia marcescens for microinjected instar III and IV gypsy moth larvae was 7.5 and 14.5 viable cells, respectively. Percentage and rate of mortality were found to be highly variable among replicates of the same instar and between instars in free-feeding bioassays. Mortality in second instar larvae occurred before ecdysis, whereas practically no mortality occurred in third and fourth instars until the molting period. Neither Boivin endotoxin preparations nor culture filtrates were toxic to instar III larvae when administered per os or by microinjection. Histological evidence indicated that the microorganism invaded the hemocoel of healthy or predisposed insects through the gut wall. The rapid multiplication of the bacterium in the hemocoel of infected insects, followed by death in the absence of extensive tissue damage, indicated mortality was due to a septicemia. The histological and biological evidence presented indicated that the microorganism would be less than effective if utilized as a conventional microbial insecticide. © 1976.

A gram-negative bacillus, pathogenic for gypsy moth larvae, was characterized culturally, morphologically, and physiologically as a member of the Serratia group of the family Enterobacteriaceae. The microorganism lacked the pigmentation characteristic of the group but was generally distinguished from closely related members of the family by its inability to produce gas from glucose, inositol, glycerol, and cellobiose; its rapid liquefaction of gelatin; and its failure to ferment raffinose or arabinose. The microorganism displayed lecithinase, deoxyribonuclease, and chitinase activity. The percentage of G + C in DNA from this bacterium was within the range reported for known strains of Serratia marcescens. © 1976.

1. 1. The influence of thermal acclimation on cable constants of the median giant axon of earthworms, Lumbricus terrestris L., has been studied using standard intracellular stimulating and recording techniques. 2. 2. Acute cooling of axons from warm-acclimated worms resulted in changes in cable constants, some of which were partially compensated for (reversed) after cold acclimation. 3. 3. Of special interest is the relative behavior of specific axoplasm resistance in response to acute temperature change in warm- and cold-acclimated worms. 4. 4. The results suggest that thermal acclimation alters the properties of the axoplasm and that the resulting changes in cable constants contribute to compensatory adjustments in nerve conduction velocity after acclimation. © 1973.

Growth and survival of scaled sardine, Harengula pensacolae, larvae were evaluated in laboratory rearing experiments at temperatures ranging from 21 to 35 C. Fertilized eggs were obtained in plankton collections made near Miami, Florida, in summer 1971. Larvae were reared for 15 days after hatching in temperature-controlled, 75-liter aquaria. Hatching success was high at all temperatures but larvae did not survive at 35 C, and survival was poor at 21-23 C. Survival was best at temperatures between 26 and 32 C. Mean daily growth increments ranged from 0.056 mm at 21-23 C to 1.035 mm at 32 C. Growth in relation to temperature was expressed by the equation Y = -0.8474 + 0.0537X, where Y equals daily growth increment and X equals temperature. Larval behavior was normal at 26 to 33.5 C. Critical high and low temperatures for larval survival were 35 C and approximately 20 C. © 1972 by the American Fisheries Society.

The most commonly used measurement of radiation damage to seeds is seedling height, the mean height a lot of seeds attains at some time during exponential growth. If planted immediately post-irradiation, seeds of a dose lot give a normal height distribution, but if stored before planting give very abnormal and even bimodal height distributions. By within-seed comparisons of chromosome abnormality (from roots excised at 24-36 hr) with height (attained by 7-9 days) in irradiated barley seeds, it is shown that damage to height and to chromosomes are closely correlated, even within a treatment in which great heterogeneity occurs. The two effects have equal radiosensitivity, but different shoulders to their dose curves. Seedling height is not depressed until 25-30 per cent of the cells bear chromosomal abnormalities. The heterogeneity observed is not due to a between-seed heterogeneity in dose or in oxygen content, and probably not in moisture. These experiments show that the heterogeneity arises from factors that operate on post-irradiation (indirect) storage damage, but are without effect on during-irradiation damage (direct). © 1969 Pergamon Press Ltd.

The paper presents methods of space allocation applicable to architectural design. These techniques have been developed in the past twenty years and are presented in this paper in such a way that they mav also be applied to other disciplines. Four categories are presented that identify the variations in the dimensioning of the elements, either unit dimension or variable dimension, and the variation in the shape of the boundary, either a simple rectangle or a multi-faceted boundary.

Abstract  Evaluating a student's accent in a foreign language is a complex process. Although it is obvious to the instructor whether or not the sound is correct, it is difficult for students both to hear the incorrect sound and to correct it. Too often the instructor merely tells the students that they have spoken incorrectly, expresses the sound properly, and then tries, often without lasting success, to have the students imitate. In a phonetically oriented course, diagrams are used as visual aids to teach correct articulation; but, especially at lower levels, it is difficult and often uninspiring for students to identify their speech production with such text figures. In a new method an improvised television “studio” captures the individual student's speech in an easily reviewable, permanent form on videotape. This visual, personal approach can make spectacular improvement in pronunciation, and the technique appears to be adaptable to any level of language learning. © 1981 American Council on the Teaching of Foreign Languages

Many special education students have the knowledge but are unable or unprepared to demonstrate that knowledge while taking a test. © 1988, SAGE Publications. All rights reserved.

This paper describes an approach to cognitive assessment that involves a synthesis of the traditional psychometric approach and the more recent information-processing approaches. In this combined approach, psychometric tests arc supplemented by tasks adapted from information-processing research. The paper focuses on the use of the approach with disabled readers, although the approach may be generalized to many different populations. The Test of Syllable and Phoneme Counting, a measure of awareness of the sound structure of speech, is described, as an example of an information-processing task that would be useful with younger disabled readers. Guidelines for using information-processing measures are also discussed. © 1986 by The Haworth Press, Inc. All rights reserved.