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Second Condition (second + condition)
Selected AbstractsPostnatal stress in mice: Does "stressing" the mother have the same effect as "stressing" the pups?DEVELOPMENTAL PSYCHOBIOLOGY, Issue 4 2004A. Moles Abstract Short- and long-term effects of brief maternal separation, maternal exposure to novel male odor, and standard rearing were compared in NMRI mice. The first condition consisted of 15 min of daily exposure of pups to clean bedding (CB), and the second condition consisted of 15 min of mothers' exposure to the odor of strange males (SM), for 14 days after birth starting from postnatal Day 1. Thus, both conditions entailed the same period of maternal separation. A control mother,offspring group was left undisturbed (nonhandled, N-H). Corticosterone levels of mothers and pups were measured at the end of the last manipulation session. Corticosterone levels were higher in SM mothers, differing from both those of CB and of control dams; CB pups showed the highest corticosterone levels in comparison with the pups belonging to the other groups. Maternal behavior observed as furthest as possible from the daily separation session did not differ among the three groups. The behavioral response to 0.5 mg/kg of apomorphine in 15-day-old pups was enhanced in both CB and SM animals, which suggests an alteration of dopaminergic functioning. Finally, adult CB and SM male mice showed an increase in the percentage of time and entries into the open arms of the plus-maze in comparison to nonhandled males. This study indicates that exposure to ecologically relevant stimuli elicited a stress response in lactating dams. This "social stress" brings about short- and long-term effects in the offspring, even in the absence of any direct manipulation of the pups. © 2004 Wiley Periodicals, Inc. Dev Psychobiol 44: 230,237, 2004. [source] A technique for rapid single-echo spin-echo T2 mappingMAGNETIC RESONANCE IN MEDICINE, Issue 2 2010Marshall S. Sussman Abstract A rapid technique for mapping of T2 relaxation times is presented. The method is based on the conventional single-echo spin echo approach but uses a much shorter pulse repetition time to accelerate data acquisition. The premise of the new method is the use of a constant difference between the echo time and pulse repetition time, which removes the conventional and restrictive requirement of pulse repetition time , T1. Theoretical and simulation investigations were performed to evaluate the criteria for accurate T2 measurements. Measured T2s were shown to be within 1% error as long as the key criterion of pulse repetition time/T2 ,3 is met. Strictly, a second condition of echo time/T1 , 1 is also required. However, violations of this condition were found to have minimal impact in most clinical scenarios. Validation was conducted in phantoms and in vivo T2 mapping of healthy cartilage and brain. The proposed method offers all the advantages of single-echo spin echo imaging (e.g., immunity to stimulated echo effects, robustness to static field inhomogeneity, flexibility in the number and choice of echo times) in a considerably reduced amount of time and is readily implemented on any clinical scanner. Magn Reson Med, 2010. © 2010 Wiley-Liss, Inc. [source] Scanning electron microscopy applied to seed-borne fungi examinationMICROSCOPY RESEARCH AND TECHNIQUE, Issue 7 2009Marcelo De Carvalho Alves Abstract The aim of this study was to test the standard scanning electron microscopy (SEM) as a potential alternative to study seed-borne fungi in seeds, by two different conditions of blotter test and water restriction treatment. In the blotter test, seeds were subjected to conditions that enabled pathogen growth and expression, whereas the water restriction method consisted in preventing seed germination during the incubation period, resulting in the artificial inoculation of fungi. In the first condition, seeds of common bean (Phaseolus vulgaris L.), maize (Zea mays L.), and cotton (Gossypium hirsutum L.) were submitted to the standard blotter test and then prepared and observed with SEM. In the second condition, seeds of cotton (G. hirsutum), soybean (Glycine max L.), and common bean (P. vulgaris L.) were, respectively, inoculated with Colletotrichum gossypii var. cephalosporioides, Colletotrichum truncatum, and Colletotrichum lindemuthianum by the water restriction technique, followed by preparation and observation with SEM. The standard SEM methodology was adopted to prepare the specimens. Considering the seeds submitted to the blotter test, it was possible to identify Fusarium sp. on maize, C. gossypii var. cephalosporioides, and Fusarium oxysporum on cotton, Aspergillus flavus, Penicillium sp., Rhizopus sp., and Mucor sp. on common bean. Structures of C. gossypii var. cephalosporioides, C. truncatum, and C. lindemuthianum were observed in the surface of inoculated seeds. Microsc. Res. Tech., 2009. © 2009 Wiley-Liss, Inc. [source] The effect of perceived length on visuomotor localizationOPHTHALMIC AND PHYSIOLOGICAL OPTICS, Issue 3 2001Nick Fogt Summary Purpose: The purpose of this experiment was to study visuomotor localization in the presence of either a horizontal array of equally spaced dots or a thin horizontal line. Methods: Pointing behavior was used to assess directional localization. In experiment 1, subjects were made myopic using a contact lens and then corrected with a spectacle lens. Subjects were tested in the presence and absence of a regularly spaced, horizontal array of dots with and without the contact lens/spectacle combination. In experiment 2, subjects wore the contact lens/spectacle in all cases. Some subjects were tested in the presence and then in the absence of a regularly spaced, horizontal array of dots while the order of conditions was reversed for other subjects. In experiments 3 and 4, subjects were tested without the contact lens/spectacle combination. In experiment 3, subjects were tested in the absence and then in the presence of a regularly spaced, horizontal arrays of dots. In experiment 4, subjects were tested in the absence and then in the presence of a thin horizontal line. Results: In experiment 1, in the absence of the array of dots, subjects undershot targets with the contact lens/spectacle combination. When the array was present, pointing with the contact lens/spectacle combination was accurate. In experiment 2, subjects undershot targets in the absence of the array of dots if this condition was performed first. If the array was present in the initial condition, the pointing undershoot in the second condition (array absent) was reduced. In all cases, the pointing undershoot was reduced in the presence of the array. In experiments 3 and 4, a pointing overshoot was found in the presence of an array of dots or a thin line. Conclusions: It is concluded that extraretinal eye position information is not the primary determinant of visuomotor localization in the presence of a horizontal contour. The overshoot produced by a horizontal contour may be related to a length illusion brought about by spatial filtering in the visual system or inaccurate distance judgments. [source] Teaching cooperative play to typical children utilizing a behavior modeling approach: a systematic replicationBEHAVIORAL INTERVENTIONS, Issue 3 2002Erik Jahr This study investigated the acquisition of cooperative play in three typical children. The differential effectiveness of two different modeling conditions was compared, where in the first condition the children were trained to observe and imitate modeled cooperative play. In the second condition the children observed and described the modeled play prior to imitation. During training, modeled play episodes varied across play topics. The criterion for mastery in training was correct responding on first trial with new modeled play episodes. The results showed that the children became able to take turns in novel episodes of cooperative play and to show play variability only after including verbal description as part of the modeling procedure. Copyright © 2002 John Wiley & Sons, Ltd. [source] The effect of providing choices on skill acquisition and competing behavior of children with autism during discrete trial instructionBEHAVIORAL INTERVENTIONS, Issue 1 2002Bobby Newman Discrete trial instruction was carried out for three students with autism. An alternating treatments design was implemented. In one condition, teachers chose the reinforcers to be used and the order in which programs were conducted. In a second condition, students chose the order of programs and the reinforcers to be used. Speed of skill acquisition and the presence of competing behavior such as tantrums, aggression, escape attempts or idiosyncratic noncompliance responses were measured. Speed of skill acquisition did not differ between the two conditions, but competing behavior was markedly reduced during student choice conditions. Copyright © 2002 John Wiley & Sons, Ltd. [source] Expression, purification, crystallization and preliminary X-ray diffraction analysis of ,-11 giardin from Giardia lambliaACTA CRYSTALLOGRAPHICA SECTION F (ELECTRONIC), Issue 11 2006Puja Pathuri ,-11 Giardin, a protein from the annexin superfamily, is a 35.0,kDa protein from the intestinal protozoan parasite Giardia lamblia which triggers a form of diarrhea called giardiasis. Here, the cloning, expression, purification and the crystallization of ,-11 giardin under two different conditions and in two different space groups is reported. Crystals from the first condition diffracted to 1.1,Å and belong to a primitive orthorhombic space group, while crystals from the second condition, which included calcium in the crystallization solution, diffracted to 2.93,Å and belong to a primitive monoclinic space group. Determination of the detailed atomic structure of ,-11 giardin will provide a better insight into its biological function and might establish whether this class of proteins is a potential drug target against giardiasis. [source] A proteomic view of the facultatively chemolithoautotrophic lifestyle of Ralstonia eutropha H16PROTEINS: STRUCTURE, FUNCTION AND BIOINFORMATICS, Issue 22 2009Edward Schwartz Abstract Ralstonia eutropha H16 is an H2 -oxidizing, facultative chemolithoautotroph. Using 2-DE in conjunction with peptide mass spectrometry we have cataloged the soluble proteins of this bacterium during growth on different substrates: (i) H2 and CO2, (ii) succinate and (iii) glycerol. The first and second conditions represent purely lithoautotrophic and purely organoheterotrophic nutrition, respectively. The third growth regime permits formation of the H2 -oxidizing and CO2 -fixing systems concomitant to utilization of an organic substrate, thus enabling mixotrophic growth. The latter type of nutrition is probably the relevant one with respect to the situation faced by the organism in its natural habitats, i.e. soil and mud. Aside from the hydrogenase and Calvin-cycle enzymes, the protein inventories of the H2 -CO2 - and succinate-grown cells did not reveal major qualitative differences. The protein complement of the glycerol-grown cells resembled that of the lithoautotrophic cells. Phosphoenolpyruvate (PEP) carboxykinase was present under all three growth conditions, whereas PEP carboxylase was not detectable, supporting earlier findings that PEP carboxykinase is alone responsible for the anaplerotic production of oxaloacetate from PEP. The elevated levels of oxidative stress proteins in the glycerol-grown cells point to a significant challenge by ROS under these conditions. The results reported here are in agreement with earlier physiological and enzymological studies indicating that R. eutropha H16 has a heterotrophic core metabolism onto which the functions of lithoautotrophy have been grafted. [source] | |||||||||||||