387 research outputs found
Hypochlorite Oxidation of Nitrilotriacetic Acid
The chemical degradation of nitrilotriacetic acid (NTA) by sodium hypochlorite is examined. Preliminary work indicates that NTA undergoes decarboxylation. In the second phase of this investigation (S92), the work was mainly concerned with the products from the reaction of NTA with hypochlorite. The product of decarboxylation has been found to be iminodiacetic acid. The decrease in concentration of hypochlorite per unit time was studied over a pH range of 7-14 and in the presence of lead, calcium, zinc, and copper ions
Perceived ideological bias in the college classroom and the role of student reflective thinking: A proposed model
The role ideology plays in the university classroom is a continual issue of debate. A common public perception has been that academics are a liberal elite, and that they, in the words of conservative activist David Horowitz, âbehave as political advocates in the classroom, express opinions in a partisan manner on controversial issues irrelevant to the academic subject, and even grade students in a manner designed to enforce their conformity to professorial prejudicesâ (2007, p. 188). The Chronicle of Higher Education demonstrated how pervasive this view has become with a 2004 public opinion poll that found 51% of 1,000 individuals surveyed in the United States (U.S.) believed college faculty improperly introduced a liberal bias into their classrooms (A Special Report). In contrast, the American Association of University Professorsâ Statement on Professional Ethics states âAs teachers, professors encourage the free pursuit of learning in their students ⊠Professors demonstrate respect for students as individuals and adhere to their proper roles as intellectual guides and counselorsâ (2009, p. 4). There is clearly a disconnect between what faculty profess to do and what many outside of higher education perceive to be happening. If this disconnect can be addressed through changes in pedagogy, even if only partially, then such changes should be explored. This study explores how student reflective thinking, student perceptions of ideological bias, and student reactions to ideological bias interact. Understanding the relationship between these three variables may help educators communicate more effectively with students in an effort to foster open minded inquiry
Using Participatory Focus Groups Of Graduate Students To Improve Academic Departments: A Case Example
The authors report on a participatory focus group evaluation of an academic department. The 20 participants, and the majority of the evaluators, were graduate students in that department. The authors report on their methods, their reflections, ethical issues they encountered and what they did about them, and how they used the results
Growth hormone modulates hippocampal excitatory synaptic transmission and plasticity in old rats
Cataloged from PDF version of article.Alterations in the alpha-amino-3-hydroxy-5-methyl-4-isoxazolepropionate receptor (AMPA-R) and N-methyl-D-aspartate receptor
(NMDA-R) have been documented in aged animals and may contribute to changes in hippocampal-dependent memory. Growth hormone
(GH) regulates AMPA-R and NMDA-R-dependent excitatory transmission and decreases with age. Chronic GH treatment mitigates
age-related cognitive decline. An in vitro CA1 hippocampal slice preparation was used to compare hippocampal excitatory transmission and
plasticity in old animals treated for 6â8 months with either saline or GH. Our findings indicate that GH treatment restores NMDA-Rdependent
basal synaptic transmission in old rats to young adult levels and enhances both AMPA-R-dependent basal synaptic transmission
and long-term potentiation. These alterations in synaptic function occurred in the absence of changes in presynaptic function, as measured
by paired-pulse ratios, the total protein levels of AMPA-R and NMDA-R subunits or in plasma or hippocampal levels of insulin-like growth
factor-I. These data suggest a direct role for GH in altering age-related changes in excitatory transmission and provide a possible cellular
mechanism through which GH changes the course of cognitive decline.
© 2012 Elsevier Inc. All rights reserved
Complexity of the self-schema and responses to disconfirming feedback
This study focused on complexity of the self-schema as one factor that influences people's responses to social feedback that challenges their established view of self. Complexity refers to the number of independent attributes included in the schema. A card-sorting task (Zajonc, 1960) was used to identify the high- and low-complexity groups. Subjects were given bogus feedback relevant to the targeted domain of self-knowledge, and changes in self-descriptiveness ratings and response latency times were monitored. Results suggest that high-complexity subjects were able to attend to and encode the disconfirming feedback, while low-complexity subjects responded by rejecting the feedback and reasserting positive aspects of the self. The implications of these findings for clarifying the process of self-schema updating, revision, and change are discussed.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/44337/1/10608_2006_Article_BF02357222.pd
Perceiving Mixed Valence Emotions Reduces Intergroup Dehumanization
To deny othersâ humanity is one of the most heinous forms of intergroup prejudice. Given evidence that perceiving various forms of complexity in outgroup members reduces intergroup prejudice, we investigated across three experiments whether the novel dimension of emotional complexity, or outgroup membersâ joint experience of mixed-valence emotions, would also reduce their dehumanization. Experiment 1 found that perceiving fictitious aliensâ experience of the same primary emotions (e.g., sadness) presented in mixed vs. non-mixed valence pairs led to reduced prejudice via attenuated dehumanization, i.e. attribution of uniquely human emotions. Experiment 2 confirmed these results, using an unfamiliar real-world group as an outgroup target. Experiment 3 used a familiar outgroup and found generally similar effects, reducing social distance through reduced dehumanization. These processes suggest that an alternate route to reduced dehumanizing of outgroups might involve presenting mixed valence emotions
Development and characterization of a Yucatan miniature biomedical pig permanent middle cerebral artery occlusion stroke model
BACKGROUND: Efforts to develop stroke treatments have met with limited success despite an intense need to produce novel treatments. The failed translation of many of these therapies in clinical trials has lead to a close examination of the therapeutic development process. One of the major factors believed to be limiting effective screening of these treatments is the absence of an animal model more predictive of human responses to treatments. The pig may potentially fill this gap with a gyrencephalic brain that is larger in size with a more similar gray-white matter composition to humans than traditional stroke animal models. In this study we develop and characterize a novel pig middle cerebral artery occlusion (MCAO) ischemic stroke model. METHODS: Eleven male pigs underwent MCAO surgery with the first 4 landrace pigs utilized to optimize stroke procedure and 7 additional Yucatan stroked pigs studied over a 90Â day period. MRI analysis was done at 24Â hrs and 90Â days and included T2w, T2w FLAIR, T1w FLAIR and DWI sequences and associated ADC maps. Pigs were sacrificed at 90Â days and underwent gross and microscopic histological evaluation. Significance in quantitative changes was determined by two-way analysis of variance and post-hoc Tukeyâs Pair-Wise comparisons. RESULTS: MRI analysis of animals that underwent MCAO surgery at 24Â hrs had hyperintense regions in T2w and DWI images with corresponding ADC maps having hypointense regions indicating cytotoxic edema consistent with an ischemic stroke. At 90Â days, region of interest analysis of T1 FLAIR and ADC maps had an average lesion size of 59.17Â cc, a loss of 8% brain matter. Histological examination of pig brains showed atrophy and loss of tissue, consistent with MRI, as well as glial scar formation and macrophage infiltration. CONCLUSIONS: The MCAO procedure led to significant and consistent strokes with high survivability. These results suggest that the pig model is potentially a robust system for the study of stroke pathophysiology and potential diagnostics and therapeutics
The association between depressive symptoms and executive control impairments in response to emotional and non-emotional information
Depression has been linked with impaired executive control and specific impairments in inhibition of negative material. To date, only a few studies have examined the relationship between depressive symptoms and executive functions in response to emotional information. Using a new paradigm, the Affective Shift Task (AST), the present study examined whether depressive symptoms in general, and rumination specifically, are related to impairments in inhibition and set shifting in response to emotional and non-emotional material. The main finding was that depressive symptoms in general were not related to inhibition. Set-shifting impairments were only observed in moderate to severely depressed individuals. Interestingly, rumination was related to inhibition impairments, specifically when processing negative information, as well as impaired set shifting as reflected in a larger shift cost. These results are discussed in relation to cognitive views on vulnerability for depression
Vocal Fundamental and Formant Frequencies Affect Perceptions of Speaker Cooperativeness
In recent years, the perception of social traits in faces and voices has received much attention. Facial and vocal masculinity are linked to perceptions of trustworthiness; however, while feminine faces are generally considered to be trustworthy, vocal trustworthiness is associated with masculinized vocal features. Vocal traits such as pitch and formants have previously been associated with perceived social traits such as trustworthiness and dominance, but the link between these measurements and perceptions of cooperativeness have yet to be examined. In Experiment 1, cooperativeness ratings of male and female voices were examined against four vocal measurements: fundamental frequency (F0), pitch variation (F0−SD), formant dispersion (Df), and formant position (Pf). Feminine pitch traits (F0 and F0−SD) and masculine formant traits (Df and Pf) were associated with higher cooperativeness ratings. In Experiment 2, manipulated voices with feminized F0 were found to be more cooperative than voices with masculinized F0, among both male and female speakers, confirming our results from Experiment 1. Feminine pitch qualities may indicate an individual who is friendly and non-threatening, while masculine formant qualities may reflect an individual that is socially dominant or prestigious, and the perception of these associated traits may influence the perceived cooperativeness of the speakers
- âŠ