Pyridoxine hydrochloride (2.10 g, 10.2 mmol) and Rose Bengal (17 mg) were dissolved in phosphate ... more Pyridoxine hydrochloride (2.10 g, 10.2 mmol) and Rose Bengal (17 mg) were dissolved in phosphate buffer (280 mL, 0.25 M, pH 7.5). The resulting solution was sparged with oxygen and irradiated with light (see General Methods) for 4 hours at room temperature. The mixture of products was lyophilized and purified via column chromatography on silica gel (15% MeOH in CH 2 Cl 2). The fractions containing the major product yielded a white solid (0.89 g, 43%). The
Rats implanted with bipolar electrodes aimed at the medial forebrain bundle (MFB) were trained to... more Rats implanted with bipolar electrodes aimed at the medial forebrain bundle (MFB) were trained to self-stimulate. Six daily injections of 2 mEq/kg of the chloride salts of Li+, Rb+ or Cs+ were administered and the rate of intracranial self-stimulation (ICSS) was recorded. Lithium caused a reversible decrease in ICSS rate, beginning on the second day and returning to pretreatment rate on the fourth day of injections. The decrease was more pronounced in animals with high baseline rate (over 500 responses/10 min) than in low responders. Rubidium enhanced ICSS rate whereas cesium had no effect. These results agree with other accumulating data showing the opposite effects of Li+ and Rb+, but their relevance to effective disorders is not clear.
The rate of isotopic exchange of oxygen between phosphorous acid and water was measured over the ... more The rate of isotopic exchange of oxygen between phosphorous acid and water was measured over the range from pH 10 to 9.4N-HClO/sub 4/. The observed rate of exchange increases continuously with increasing acidity. The rate constants for the exchange between water and the various ionic species present at different pH's were calculated and the mechanisms of the exchange discussed. (auth)
... Appendix Physics Attitude Scale (PAS)* (mean ratings for the whole sample (N = 157) appear in... more ... Appendix Physics Attitude Scale (PAS)* (mean ratings for the whole sample (N = 157) appear in brackets) ... 52. Parents have usually no effect on the attitudes of students towards 53. ... 57. The nature of girls drives them away from physics. 58. ...
In a study of the mechanisms controlling the learned helplessness phenomenon, rats were exposed t... more In a study of the mechanisms controlling the learned helplessness phenomenon, rats were exposed to either inescapable preshocks or control procedures, treated with one of three dosages of desmethylimipramine, and tested for later adaptive responding. This catecholamine modulator attenuated the deficits in escape responding that ordinarily follow prior exposure to inescapable preshocks, and it did so in a dose-dependent fashion. These findings support the position that the learned helplessness phenomenon is mediated by catecholamine changes.
Young toads, Xenopus laevis, were trained for dark avoidance in a passive avoidance paradigm usin... more Young toads, Xenopus laevis, were trained for dark avoidance in a passive avoidance paradigm using electric shock in a fully automatic training and recording procedure. Dark avoidance was acquired within approximately 30 min and was retained on retesting 24 h later. Comparison of the performance of the toads during training and during retesting was used as an indicator for saving or reinforced retention. Control experiments demonstrated that changes in behavior were due to learning and not to nonassociative effects such as pseudoconditioning, increased sensitization to shock, or acquaintance with the testing apparatus. We wish to thank 1. Sher for his excellent technical assistance.
It is fairly well established that the objectives of science curricula can be divided into three ... more It is fairly well established that the objectives of science curricula can be divided into three major areas, namely, cognitive, affective, and psychomotor domains (Bloom, 1956). In science curricula, practical work (which is mainly in the psychomotor domain) assumes an important role (Shulman & Tamir, 1973). However, while laboratory-centered activities are perhaps the most significaut aspects of these curricula, "The development of psychomotor skills has been alnrost eomplately ignored by researchers in science education" (Ramsey & Howe, 1969). Although in the last few years several attempts have been made to incorporate practical examinations into evaluation projects (Kelly & Lister, 1969; Tamir, 1974), "The research on the relations between laboratory and other learning modes m a i n s scarce" (Shulman & Tamir, 1973).
ABSTRACT The use of small solid state detectors for behavioral studies is described. These detect... more ABSTRACT The use of small solid state detectors for behavioral studies is described. These detectors can be inserted in holders cemented to the skull of freely moving animals thus enabling the determination of uptake of radioactive matermal in an area of the brain. By injecting P32 labelled Na3PO4, the rate of incorporation of phosphate in the brain under different behavioral conditions such as sleep anesthesia, learning, etc. can be followed. The advantages of this method are the repeated measurements on the same animal, the use of live animals for both psychological and physiological studies, the possibility of kinetic and turnover studies in the brain, blood, and in principle, other organs. Using the uptake of P32 together with studies involving other isotopes such as the stable isotope O18, an estimate of the energyrequirements of the brain can be made. The detector is a lithium drifted silicon device mounted in an electroform nickel tube of 2mm O.D. and a wall thickness of ¿ 25 microns. The detector is coated with 3 microns of parylene and secured in the nickel tube with an RTV potting compound. The major components of the preamplifier are: an FET, a transistor, three resistors and three capacitors mounted behind the detector in the probe. Performance characteristics and results will be described.
Abstract Young frogs, Xenopus laevis, raised on a white background showed a slight preference for... more Abstract Young frogs, Xenopus laevis, raised on a white background showed a slight preference for the black background of a black-white preference testing apparatus. Keeping frogs for either 24 hr or 20 days on a black background resulted in a further increase in their preference for black. Injecting 1 μg of synthetic α-MSH into white-adapted frogs had no effect on their black-white preference. On the other hand, Xenopus laevis tadpoles, at an early stage of metamorphosis, raised on a white background showed a significant preference for white. Keeping these tadpoles for 24 hr on a black background resulted in a shift from white to black preference. Injecting synthetic α-MSH into white-adapted tadpoles resulted in an increase in their preference for black. A behavioral feedback mechanism appears to exist between the release of endogenous MSH when a tadpole is exposed to a black background and its subsequent preference for background color.
Pyridoxine hydrochloride (2.10 g, 10.2 mmol) and Rose Bengal (17 mg) were dissolved in phosphate ... more Pyridoxine hydrochloride (2.10 g, 10.2 mmol) and Rose Bengal (17 mg) were dissolved in phosphate buffer (280 mL, 0.25 M, pH 7.5). The resulting solution was sparged with oxygen and irradiated with light (see General Methods) for 4 hours at room temperature. The mixture of products was lyophilized and purified via column chromatography on silica gel (15% MeOH in CH 2 Cl 2). The fractions containing the major product yielded a white solid (0.89 g, 43%). The
Rats implanted with bipolar electrodes aimed at the medial forebrain bundle (MFB) were trained to... more Rats implanted with bipolar electrodes aimed at the medial forebrain bundle (MFB) were trained to self-stimulate. Six daily injections of 2 mEq/kg of the chloride salts of Li+, Rb+ or Cs+ were administered and the rate of intracranial self-stimulation (ICSS) was recorded. Lithium caused a reversible decrease in ICSS rate, beginning on the second day and returning to pretreatment rate on the fourth day of injections. The decrease was more pronounced in animals with high baseline rate (over 500 responses/10 min) than in low responders. Rubidium enhanced ICSS rate whereas cesium had no effect. These results agree with other accumulating data showing the opposite effects of Li+ and Rb+, but their relevance to effective disorders is not clear.
The rate of isotopic exchange of oxygen between phosphorous acid and water was measured over the ... more The rate of isotopic exchange of oxygen between phosphorous acid and water was measured over the range from pH 10 to 9.4N-HClO/sub 4/. The observed rate of exchange increases continuously with increasing acidity. The rate constants for the exchange between water and the various ionic species present at different pH's were calculated and the mechanisms of the exchange discussed. (auth)
... Appendix Physics Attitude Scale (PAS)* (mean ratings for the whole sample (N = 157) appear in... more ... Appendix Physics Attitude Scale (PAS)* (mean ratings for the whole sample (N = 157) appear in brackets) ... 52. Parents have usually no effect on the attitudes of students towards 53. ... 57. The nature of girls drives them away from physics. 58. ...
In a study of the mechanisms controlling the learned helplessness phenomenon, rats were exposed t... more In a study of the mechanisms controlling the learned helplessness phenomenon, rats were exposed to either inescapable preshocks or control procedures, treated with one of three dosages of desmethylimipramine, and tested for later adaptive responding. This catecholamine modulator attenuated the deficits in escape responding that ordinarily follow prior exposure to inescapable preshocks, and it did so in a dose-dependent fashion. These findings support the position that the learned helplessness phenomenon is mediated by catecholamine changes.
Young toads, Xenopus laevis, were trained for dark avoidance in a passive avoidance paradigm usin... more Young toads, Xenopus laevis, were trained for dark avoidance in a passive avoidance paradigm using electric shock in a fully automatic training and recording procedure. Dark avoidance was acquired within approximately 30 min and was retained on retesting 24 h later. Comparison of the performance of the toads during training and during retesting was used as an indicator for saving or reinforced retention. Control experiments demonstrated that changes in behavior were due to learning and not to nonassociative effects such as pseudoconditioning, increased sensitization to shock, or acquaintance with the testing apparatus. We wish to thank 1. Sher for his excellent technical assistance.
It is fairly well established that the objectives of science curricula can be divided into three ... more It is fairly well established that the objectives of science curricula can be divided into three major areas, namely, cognitive, affective, and psychomotor domains (Bloom, 1956). In science curricula, practical work (which is mainly in the psychomotor domain) assumes an important role (Shulman & Tamir, 1973). However, while laboratory-centered activities are perhaps the most significaut aspects of these curricula, "The development of psychomotor skills has been alnrost eomplately ignored by researchers in science education" (Ramsey & Howe, 1969). Although in the last few years several attempts have been made to incorporate practical examinations into evaluation projects (Kelly & Lister, 1969; Tamir, 1974), "The research on the relations between laboratory and other learning modes m a i n s scarce" (Shulman & Tamir, 1973).
ABSTRACT The use of small solid state detectors for behavioral studies is described. These detect... more ABSTRACT The use of small solid state detectors for behavioral studies is described. These detectors can be inserted in holders cemented to the skull of freely moving animals thus enabling the determination of uptake of radioactive matermal in an area of the brain. By injecting P32 labelled Na3PO4, the rate of incorporation of phosphate in the brain under different behavioral conditions such as sleep anesthesia, learning, etc. can be followed. The advantages of this method are the repeated measurements on the same animal, the use of live animals for both psychological and physiological studies, the possibility of kinetic and turnover studies in the brain, blood, and in principle, other organs. Using the uptake of P32 together with studies involving other isotopes such as the stable isotope O18, an estimate of the energyrequirements of the brain can be made. The detector is a lithium drifted silicon device mounted in an electroform nickel tube of 2mm O.D. and a wall thickness of ¿ 25 microns. The detector is coated with 3 microns of parylene and secured in the nickel tube with an RTV potting compound. The major components of the preamplifier are: an FET, a transistor, three resistors and three capacitors mounted behind the detector in the probe. Performance characteristics and results will be described.
Abstract Young frogs, Xenopus laevis, raised on a white background showed a slight preference for... more Abstract Young frogs, Xenopus laevis, raised on a white background showed a slight preference for the black background of a black-white preference testing apparatus. Keeping frogs for either 24 hr or 20 days on a black background resulted in a further increase in their preference for black. Injecting 1 μg of synthetic α-MSH into white-adapted frogs had no effect on their black-white preference. On the other hand, Xenopus laevis tadpoles, at an early stage of metamorphosis, raised on a white background showed a significant preference for white. Keeping these tadpoles for 24 hr on a black background resulted in a shift from white to black preference. Injecting synthetic α-MSH into white-adapted tadpoles resulted in an increase in their preference for black. A behavioral feedback mechanism appears to exist between the release of endogenous MSH when a tadpole is exposed to a black background and its subsequent preference for background color.
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