295 research outputs found
Motivational Effects of Goal Orientation
According to achievement goal theory, individuals set mastery or performance goals to accomplish challenging tasks. In addition, they can either approach or avoid the goal they are achieving. Mastery goals show positive correlation to intrinsic motivation while performance goals are linked to extrinsic motivation. Goal setting also affects motivation for completing tasks and perception of self-efficacious behavior while performing tasks. Receiving feedback has been positively correlated with success in learning and intrinsic motivation. The present research manipulates goal orientation through the accomplishment of a word find in an online experimental setting to test the effect on feedback, intrinsic motivation, choice, and self-efficacy. Positive versus highly positive feedback conditions were used after the word find to test effects on perceived competence following a task. For the approach-mastery goal condition, we found main effects for intrinsic motivation, perceived choice, task choice, and views of task importance. Additionally, we found a main effect for perceived competence for our highly positive feedback condition versus giving just positive feedback. These results demonstrate support for accomplishing challenging tasks with mastery goals versus performance goals and the usage of more positive feedback in a feedback condition
Watch Me Give: Narcissism as a Moderator to Donating to a Nonprofit
With increased online connectivity in the current generation, more non-for-profit organizations are focusing their efforts on producing online marketing appeals. It has, therefore, become necessary to identify the effect some appeals have on different people. The present study seeks to determine whether an organization offering increased recognition will result in a greater willingness to give by people with narcissistic personalities. Additionally, it will determine if âwillingnessâ to give or âamountâ given are different between genders or employment status, as prior research suggests. Results indicated that whether the organization offered increased recognition or not, narcissism did not affect willingness to give or amount given. Women were more willing to give than men and employment status did not hold any bearing on the willingness to give or amount given. Limitations of the study are provided and implications for future research are discussed
The Short Dark Triad and Giving to Nonprofits
The present study examines whether âdemonstrable utility,â the belief that giving provides immediate or future tangible benefits (Sargeant, Ford, & West, 2006) significantly correlates to the adverse personality traits Machiavellianism and narcissism as they are defined in the Short Dark Triad (Paulhus & Williams, 2002). Two-hundred and twelve participants were gathered from Kennesaw State University to participate in a 20-minute online survey. While other factors were tested, attention was placed on demonstrable utility. Simple linear regression models were used to determine the relationship between demonstrable utility, Machiavellianism, and narcissism. A post-hoc Sobelâs mediation test was used to establish the different relationships that the Short Dark Triad (SD3), a measure of the dark personality traits narcissism, Machiavellianism, and psychopathy, had with factors in the model of perceptual determinants of giving to a nonprofit. Demonstrable utility was found predictive of both narcissism and Machiavellianism, and the factors emotional utility, responsiveness, communication quality, and demonstrable utility were found related to the SD3. Studies in the future might take into account adverse personality traits such as Machiavellianism and narcissism when developing constructs of giving behavior, and more studies should focus on the effect of nonprofit marketing appeals centered on these personality traits
Small Intensely Fluorescent Cells in Culture: Role of Glucocorticoids and Growth Factors in Their Development and lnterconversions with other Neural Crest Derivatives
The neural crest gives rise to a number of adrenergic derivatives, including sympathetic neurons and adrenal chromaffin cells, which contain catecholamines (CAs) but differ in other morphological and functional characteristics. Small intensely fluorescent (SIF) cells, which exist primarily as a minority cell population in autonomic ganglia, are a third cell type in the sympathoadrenal branch of the neural crest lineage. In some respects these cells appear intermediate in phenotype between sympathetic neurons and adrenal chromaffin cells. We established pure dissociated cell cultures of SIF cells from rat superior cervical ganglia (SCG) and used these to study the role of environmental factors in SIF cell development and the relationship of these cells to the other cell types of the sympathoadrenal lineage. When cells from neonatal rat SCG were grown for 3 weeks in the presence of glucocorticoid and in the absence of nerve growth factor (NGF), pure cultures of SIF cells developed. The properties of the cells included (i) small cell size and the occasional presence of short neurites, (ii) intense CA histofluorescence and immunoreactivity for CA synthetic enzymes, (iii) synthesis and storage of CA from radioactive precursors, and (iv) characteristic ultrastructure. The concentration of the glucocorticoid and the presence or absence of non-neuronal cell factors influenced which types of SIF cells developed. In micromolar glucocorticoid most of the cells resembled adrenal chromaffin or type II SIF cells: they displayed immunohistochemically detectable phenylethanolamine-N-methyltransferase (PNMT), synthesized and stored epinephrine, and contained large granular vesicles (100 to 300 nm). When SCG cells were grown in 10(-8) M hormone, many fewer SIF cells developed and a higher percentage of these lacked PNMT immunoreactivity, had neurites, and contained vesicles of smaller mean diameter (70 to 130 nm), similar to those of type I SIF cells in vivo. In the presence of conditioned medium (medium conditioned by non- neuronal cells) as well as glucocorticoid, virtually all of the cells morphologically resembled type I SIF cells. In the absence of glucocorticoid, no SIF cells were ever observed after 3 weeks in culture. By following the development of CA histofluorescence and SIF cell ultrastructure in the cultures over time, we demonstrated that SIF cells were not present in large numbers in these cultures immediately after plating, but were induced from an apparently undifferentiated precursor by the hormonal environment, whereas most of the principal neurons died
Expression of Noradrenergic and Cholinergic Traits by Sympathetic Neurons Cultured without Serum
The ability to vary systematically the neuronal environment is one advantage afforded by the use of cell culture. Replacement of serum, a variable and undefined medium supplement, with known ingredients allows even greater control of culture conditions. We have studied biochemical and morphological properties related to neurotransmitter metabolism of rat sympathetic neurons cultured in a modified defined medium. Neuronal survival, ultrastructure, and expression of noradrenergic properties appear similar in serum-free and serum-supplemented cultures: small granular vesicles characteristic of norepinephrine storage were observed in both types of culture, and tyrosine hydroxylase activity, conversion of dopamine to norepinephrine, catecholamine production, and storage capacity are equivalent in serum-free and serum-containing cultures. Several of these properties were not exhibited at high levels in previous formulations of this defined medium. Acetylcholine production, however, was about 10-fold lower in serum-free compared to serum-supplemented cultures, consistent with the findings of lacovitti et al. (lacovitti, L., M. I. Johnson, T. H. Joh, and R. P. Bunge (1982) Neuroscience 7:2225â2239). Acetylcholine production can be induced under serum-free conditions by a previously characterized cholinergic inducing factor from heart cell conditioned medium. This responsiveness to serum-free heart cell conditioned medium indicates that serum-free cultures retain plasticity with respect to transmitter status, despite expression of noradrenergic characteristics, unlike cultured neurons of which the noradrenergic transmitter status is maintained by chronic depolarization. Thus, sympathetic neurons survive, express numerous differentiated properties, and display a novel transmitter status under serum-free conditions
Current insecticide treatments used in locust control have less of a short-term impact on Australian arid-zone reptile communities than does temporal variation
Author version made available in accordance with the publisher's policyContext: Despite the regular use of pesticides to control locusts, there is a general lack of information on the effects of locust control treatments on reptiles worldwide. Exposure to pesticides poses a significant potential hazard to reptiles, particularly small lizards, both from the direct effects of exposure, and indirectly due to their largely insectivorous diet and small home ranges.
Aims: Our study aimed to monitor the effects of two insecticides applied operationally for locust control in Australia.A phenyl pyrazole pesticide, fipronil, and a fungal biopesticide, Metarhizium anisopliae var. acridium (Green GuardÂź) were applied aerially in either a barrier or block treatment in the absence of high density locust populations, and effects on non-target Australian arid-zone reptiles were measured.
Methods: We monitored reptile abundance and community composition responses to treatment methods using a large field-based pitfall trapping experiment with replicated control and spraying treatments which approximated the scale of aerial-based locust control operations in Australia.
Key results: Neither reptile abundance nor community composition was significantly affected by locust control treatments. However, both abundance and community composition as detected by pitfall trapping changed over time, in both control and treatment plots, possibly due to a decrease in annual rainfall during the two years of the study.
Conclusions: The absence of any significant short-term pesticide treatment effects in our study suggests that the two locust control application methods studied present a relatively insignificant hazard to reptiles at our site, based on a single application. Similar to other areas of Australia, climate or climate driven vegetation change are likely to be stronger drivers of reptile abundance and community structure.
Implications: Monitoring over an area which approximates the scale of current locust control operations is an important step in understanding the possible effects of current pesticide exposure on reptile populations and will inform insecticide risk assessments in Australia. However, important information on the immediate response of individuals to insecticide application and any longer-term effects of exposure are still missing. The preliminary research reported in this paper should be complemented by future investigations on long-term and sublethal impacts of pesticide exposure on Australian native reptiles and the possible benefits provided to reptiles by the resource pulses represented in untreated high-density locust population
A Meta-Analytic Review of the Dark Triad-Intelligence Connection
We conducted a meta-analytic review of the relations between general mental ability (GMA) and the Dark Triad (DT) personality traitsâMachiavellianism, narcissism, and psychopathyâto determine if individuals who display socially exploitative social qualities tend to be more intelligent or less intelligent. Across 48 independent samples, GMA showed no consistent relation with any DT trait. These effects were not sufficient to support either the âevil geniusâ hypothesis (highly intelligent individuals tend to display socially exploitative personality traits) or the âcompensatoryâ hypothesis (less intelligent individuals compensate for their cognitive disadvantages by adopting manipulative behavioral tendencies). However, these relations were moderated, to some extent, by the sex and age of the participants, type of sample studied, and the measure of GMA
Surviving drought: a framework for understanding animal responses to small rain events in the arid zone
Large rain events drive dramatic resource pulses and the complex pulseâreserve dynamics of arid ecosystems change between highârain years and drought. However, aridâzone animal responses to shortâterm changes in climate are unknown, particularly smaller rain events that briefly interrupt longerâterm drought. Using arthropods as model animals, we determined the effects of a small rain event on arthropod abundance in western New South Wales, Australia during a longerâterm shift toward drought. Arthropod abundance decreased over 2 yr, but captures of 10 out of 15 ordinal taxa increased dramatically after the small rain event (\u3c40 \u3emm). The magnitude of increases ranged from 10.4 million% (collembolans) to 81% (spiders). After 3 months, most taxa returned to prerain abundance. However, small soilâdwelling beetles, mites, spiders, and collembolans retained high abundances despite the onset of winter temperatures and lack of subsequent rain. As predicted by pulseâreserve models, most aridâzone arthropod populations declined during drought. However, small rain events may play a role in buffering some taxa from declines during longerâterm drought or other xenobiotic influences. We outline the framework for a new model of animal responses to environmental conditions in the arid zone, as some species clearly benefit from rain inputs that do not dramatically influence primary productivity
Expression of Noradrenergic and Cholinergic Traits by Sympathetic Neurons Cultured without Serum
The ability to vary systematically the neuronal environment is one advantage afforded by the use of cell culture. Replacement of serum, a variable and undefined medium supplement, with known ingredients allows even greater control of culture conditions. We have studied biochemical and morphological properties related to neurotransmitter metabolism of rat sympathetic neurons cultured in a modified defined medium. Neuronal survival, ultrastructure, and expression of noradrenergic properties appear similar in serum-free and serum-supplemented cultures: small granular vesicles characteristic of norepinephrine storage were observed in both types of culture, and tyrosine hydroxylase activity, conversion of dopamine to norepinephrine, catecholamine production, and storage capacity are equivalent in serum-free and serum-containing cultures. Several of these properties were not exhibited at high levels in previous formulations of this defined medium. Acetylcholine production, however, was about 10-fold lower in serum-free compared to serum-supplemented cultures, consistent with the findings of lacovitti et al. (lacovitti, L., M. I. Johnson, T. H. Joh, and R. P. Bunge (1982) Neuroscience 7:2225â2239). Acetylcholine production can be induced under serum-free conditions by a previously characterized cholinergic inducing factor from heart cell conditioned medium. This responsiveness to serum-free heart cell conditioned medium indicates that serum-free cultures retain plasticity with respect to transmitter status, despite expression of noradrenergic characteristics, unlike cultured neurons of which the noradrenergic transmitter status is maintained by chronic depolarization. Thus, sympathetic neurons survive, express numerous differentiated properties, and display a novel transmitter status under serum-free conditions
Environmental Influences in the Development of Neural Crest Derivatives: Glucocorticoids, Growth Factors, and Chromaffin Cell Plasticity
The neural crest gives rise to three major adrenergic cell types: sympathetic principal neurons, adrenal chromaffin cells, and small intensely fluorescent (SIF) cells. All of these derivatives synthesize and store catecholamines, but they differ in numerous other characteristics. SIF cells appear intermediate in phenotype between the other two. We have examined the role of several environmental factors in the differentiation of sympathetic principal neurons and adrenal chromaffin cells. In previous studies of young rat adrenal chromaffin cells in dissociated cell culture, differentiated characteristics such as the presence of the enzyme phenylethanolamine N-methyltransferase (PNMT), epinephrine (E) synthesis, and large catecholamine storage vesicles were not well maintained. Here we describe long-term culture of chromaffin cells which, in the presence of micromolar glucocorticoid, maintained all of these characteristics. In addition, chromaffin cells of a variety of ages were found to be dependent on glucocorticoid for long-term survival in culture. In the absence of glucocorticoid, many adrenal chromaffin cells from neonatal rats could be rescued by nerve growth factor (NGF) administration. They extended neurites, as previously described by Unsicker and colleagues (Unsicker, K., B. Krisch, U. Otten, and H. Thoenen (1978) Proc. Natl. Acad. Sci. U.S.A. 75: 3498â3502). In contrast to previous studies, however, with long-term exposure to NGF these cells became indistinguishable from mature sympathetic neurons, as judged by the following morphological and biochemical criteria: increased cell size and loss of intense CA fluorescence in their cell bodies; acquisition of characteristic neuronal ultrastructure, including morphologically specialized synapses; loss of chromaffin granules, PNMT, and E synthesis; and acquisition of neuron markers, including tetanus toxin labeling and immunoreactivity to neurofilament protein. This conversion to neurons was markedly enhanced by addition of a non-neuronal cell conditioned medium (CM) containing a neurite-promoting factor, which acted by increasing the NGF responsiveness of the chromaffin cells. Even chromaffin cells from adult rats, which are known to grow few processes in response to NGF alone, became neuronal in the presence of this CM plus NGF. While converting to neurons, adrenal chromaffin cells transiently assumed an intermediate phenotype resembling type I SIF cells, which suggests particular developmental relationships between the different cell types of the sympathoadrenal lineage
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