Using the theoretical framework of occupational socialization, the purpose of this study was to e... more Using the theoretical framework of occupational socialization, the purpose of this study was to examine preservice physical education teachers’ beliefs and values of teachers and teaching through analysis and interpretation of favorite teacher narratives. One hundred and eighty six preservice physical education teachers’ narratives were collected and analyzed using open and axial coding (Corbin & Strauss, 2008). The qualities and characteristics identified through analysis were organized into seven inclusive sub-categories of favorite teacher characteristics and abilities and were articulated into three central themes, described as Pay it Forward, Caring in Teaching, and Motivated to Learn. The findings suggest that understanding favorite teacher influences on preservice teachers provides insights into maximizing the impact of physical education teacher education programs.
Drug use is highly concordant among members of adolescent and young adult peer groups. One potent... more Drug use is highly concordant among members of adolescent and young adult peer groups. One potential explanation for this observation is that drugs may increase the reinforcing effects of social contact, leading to greater motivation to establish and maintain contact with other members of the peer group. Several classes of drugs, particularly drugs that increase synaptic dopamine, increase the reinforcing effects of contextual stimuli, but the extent to which these drugs enhance the reinforcing effects of social contact is not known. The purpose of this study was to determine the extent to which drugs that increase synaptic dopamine, norepinephrine, and serotonin enhance the positive reinforcing effects of social contact. To this end, male and female Long-Evans rats were pretreated with acute doses of the selective dopamine reuptake inhibitor, WIN-35,428, the selective norepinephrine reuptake inhibitor, atomoxetine, the selective serotonin reuptake inhibitor, fluoxetine, the non-sel...
Heroin intake decreases during the proestrus phase of the estrous cycle in female, Long-Evans rat... more Heroin intake decreases during the proestrus phase of the estrous cycle in female, Long-Evans rats. The purpose of this study was to (1) determine if proestrus-induced decreases in heroin intake extend across rat strains and (2) determine if proestrus-induced decreases in responding extend to a nondrug reinforcer. Female rats were implanted with intravenous catheters and trained to self-administer heroin. Estrous cycle was tracked daily for the duration of the study. During testing, Lewis, Sprague-Dawley, and Long Evans rats self-administered low (0.0025 mg/kg) and high (0.0075 mg /kg) doses of heroin (Experiment 1) and then self-administered sucrose (Experiment 2) on fixed ratio (FR1) schedules of reinforcement. Heroin intake decreased significantly during proestrus in all three rat strains under at least one dose condition; however, sucrose intake did not decrease during proestrus in any strain. These data indicate that responding maintained by heroin, but not a nondrug reinforcer...
Opioids and stimulants are often used in combination for both recreational and non-recreational p... more Opioids and stimulants are often used in combination for both recreational and non-recreational purposes. High-efficacy mu opioid agonists generally increase the behavioral effects of stimulants, whereas opioid receptor antagonists generally attenuate the behavioral effects of stimulants; however, less is known regarding the interactions between stimulants and opioids possessing low to intermediate efficacy at the mu receptor. The purpose of this study was to examine the role of an opioid's relative efficacy at the mu receptor in altering the behavioral effects of dextro(d-)amphetamine. To this end, opioids possessing a range of relative efficacy at the mu receptor were examined alone and in combination with cumulative doses of d-amphetamine on a test of open-field, locomotor activity in male rats. Levorphanol, buprenorphine, butorphanol, nalbuphine, (-)-pentazocine, (-)-metazocine, (-)-cyclazocine, (-)-NANM, and nalorphine increased the locomotor effects of d-amphetamine in eit...
2006 IEEE Southwest Symposium on Image Analysis and Interpretation
Abstract A new method for the temporal segmentation of video sequences into real-world objects is... more Abstract A new method for the temporal segmentation of video sequences into real-world objects is proposed. First, each frame undergoes a color quantization step by matching like colors extracted from the previously processed frame. JSEG's color variance feature and ...
MAIN CONCLUSION A β-ketoacyl-ACP-synthase II (KAS2) like enzyme and a lysophosphatidic acid acylt... more MAIN CONCLUSION A β-ketoacyl-ACP-synthase II (KAS2) like enzyme and a lysophosphatidic acid acyltransferase (LPAT2) from Consolida ajacis catalyze gondoic acid biosynthesis and incorporation into the sn-2 position of seed TAG in engineered Camelina sativa. Gondoic acid (cis-11 eicosenoic acid, 20:1∆11) is the predominant very-long-chain fatty acid (VLCFA) in camelina (Camelina sativa) seed oil accounting for 12-15% of total triacylglycerol fatty acids. To explore the feasibility of engineering increased levels of this fatty acid in camelina seed, oils from a range of plant species were analyzed to identify those producing 20-Carbon (C20) fatty acids as the only VLCFAs in their seed oil. Seeds of Consolida and Delphinium species (Ranunculaceae) were found to contain moderate levels (0.2% to 25.5%) of C20 fatty acids without accompanying longer chain fatty acids. The C20 fatty acids were abundant in both sn-2 and sn-1/3 positions of seed TAG in Consolida, but were largely absent from the sn-2 position in Delphinium seed TAG. Through generation of a developing seed transcriptome, sequences were identified and cDNAs amplified from Consolida ajacis encoding a β-ketoacyl-ACP-synthase II like protein (CaKAS2B) that lacked a predicted chloroplast transit peptide, and two homologues of Arabidopsis thaliana lysophosphatidic acid acyltransferase 2 (CaLPAT2a and CaLPAT2b). Expression of CaKAS2B in conventional (WT) camelina and a line previously engineered for high seed oleic acid content (HO) resulted in increased seed VLCFA content. Total VLCFA levels were raised from 24 to 35% and from 7 to 23% in T3 seed from representative transformants in the WT and HO backgrounds, respectively. Gondoic acid was the predominant VLCFA in transformed HO lines with low endogenous cytoplasmic fatty acid elongation activity, suggesting limited capacity of CaKAS2B to elongate beyond C20. Expression in camelina of CaLPAT2b resulted in significantly increased C20-VLCFA esterification at the sn-2 position of seed TAG with VLCFA levels of 33.8% in this position in one transformed line compared to 0.3% at sn-2 in the corresponding control line. Only small changes in total seed VLCFA content were observed in transformed lines implying that increased VLCFA esterification capacity in camelina results in positional redistribution of VLCFAs but does not significantly enhance flux through the fatty acid elongation pathway. The full potential of CaKAS2B and CaLPAT2a for the engineering of high gondoic acid levels in camelina remains to be determined. Seed fatty acid composition of Consolida and Delphinium also provides information that may be of value in the systematics of the Ranunculaceae.
Drug-using peers are recognized as a leading factor influencing drug use among adolescents and yo... more Drug-using peers are recognized as a leading factor influencing drug use among adolescents and young adults. One mechanism by which peers influence drug use is by providing social reinforcement for using drugs. Social reinforcement may be provided in multiple ways, including by making social contact contingent on drug use (i.e., an individual must use drugs to gain/maintain access to a peer). The purpose of this study was to develop a preclinical model in which intravenous cocaine self-administration was positively reinforced by access to a social partner. Young adult male rats were trained to self-administer cocaine in operant conditioning chambers with a guillotine door that could be opened to an adjacent compartment housing either a social partner or a non-social stimulus. Once cocaine self-administration was established, the guillotine door was activated, and cocaine intake was reinforced by brief access to either a social (age- and sex-matched peer) or non-social (black-and-whi...
Previous studies have shown that low-efficacy benzodiazepines may function as full agonists, part... more Previous studies have shown that low-efficacy benzodiazepines may function as full agonists, partial agonists or antagonists, depending upon the sensitivity of the assay to detect a drug's agonist effects. To date, these differential effects have only been observed across tasks, as these drugs rarely produce full agonist and antagonist effects in a single preparation. The purpose of the present study was to examine the agonist and antagonist effects of various benzodiazepines in a motor task in which the sensitivity of the task differed across conditions. To this end, rats were trained to walk on a rotorod apparatus rotating at low (4 rpm), medium (20 rpm) and high (36 rpm) speeds, and the motor-impairing effects of representative low (bretazenil), intermediate (clonazepam) and high (diazepam) efficacy benzodiazepines were examined. Diazepam and clonazepam reduced the latency for rats to fall from the rotorod at all three speeds, with both drugs being more potent at the high speed than at lower speeds. Bretazenil was also effective at decreasing motor performance at the high speed, but was not effective at lower speeds. In drug combination tests, bretazenil antagonized the effects of diazepam and clonazepam under conditions in which it was not effective when administered alone, effectively demonstrating both full agonist and antagonist effects in the same preparation. These data indicate that the sensitivity of a motor task to detect a drug's agonist effects can be manipulated by altering its relative level of difficulty, and that lower-efficacy benzodiazepines are more sensitive than higher-efficacy benzodiazepines to these manipulations.
In this study we used anin situapproach to identify the oxidized nucleosides 8-hydroxydeoxyguanos... more In this study we used anin situapproach to identify the oxidized nucleosides 8-hydroxydeoxyguanosine (8OHdG) and 8-hydroxyguanosine (8OHG), markers of oxidative damage to DNA and RNA, respectively, in cases of Alzheimer’s disease (AD). The goal was to determine whether nuclear and mitochondrial DNA as well as RNA is damaged in AD. Immunoreactivity with monoclonal antibodies 1F7 or 15A3 recognizing both 8OHdG and 8OHG was prominent in the cytoplasm and to a lesser extent in the nucleolus and nuclear envelope in neurons within the hippocampus, subiculum, and entorhinal cortex as well as frontal, temporal, and occipital neocortex in cases of AD, whereas similar structures were immunolabeled only faintly in controls. Relative density measurement showed that there was a significant increase (p< 0.0001) in 8OHdG and 8OHG immunoreactivity with 1F7 in cases of AD (n= 22) as compared with senile (n= 13), presenile (n= 10), or young controls (n= 4). Surprisingly, the oxidized nucleoside wa...
Development of human brain neurons The earliest stages of human brain development are very diffic... more Development of human brain neurons The earliest stages of human brain development are very difficult to monitor, but using induced pluripotent stem cells (iPSCs) can help to elucidate the process. Real et al. transplanted neural progenitors derived from human iPSCs into the brains of adult mice. They used intravital imaging to visualize how resulting neurons grew and connected. The human cells produced neurons that integrated and developed synaptic networks with oscillatory activity. Dendritic pruning was observed and involved a process of branch retraction, not degeneration. Cells derived from individuals with Down syndrome, upon transplantation into the mouse brain, produced neurons that grew normally but showed reduced dendritic spine turnover and less network activity. Science , this issue p. eaau1810
Using the theoretical framework of occupational socialization, the purpose of this study was to e... more Using the theoretical framework of occupational socialization, the purpose of this study was to examine preservice physical education teachers’ beliefs and values of teachers and teaching through analysis and interpretation of favorite teacher narratives. One hundred and eighty six preservice physical education teachers’ narratives were collected and analyzed using open and axial coding (Corbin & Strauss, 2008). The qualities and characteristics identified through analysis were organized into seven inclusive sub-categories of favorite teacher characteristics and abilities and were articulated into three central themes, described as Pay it Forward, Caring in Teaching, and Motivated to Learn. The findings suggest that understanding favorite teacher influences on preservice teachers provides insights into maximizing the impact of physical education teacher education programs.
Drug use is highly concordant among members of adolescent and young adult peer groups. One potent... more Drug use is highly concordant among members of adolescent and young adult peer groups. One potential explanation for this observation is that drugs may increase the reinforcing effects of social contact, leading to greater motivation to establish and maintain contact with other members of the peer group. Several classes of drugs, particularly drugs that increase synaptic dopamine, increase the reinforcing effects of contextual stimuli, but the extent to which these drugs enhance the reinforcing effects of social contact is not known. The purpose of this study was to determine the extent to which drugs that increase synaptic dopamine, norepinephrine, and serotonin enhance the positive reinforcing effects of social contact. To this end, male and female Long-Evans rats were pretreated with acute doses of the selective dopamine reuptake inhibitor, WIN-35,428, the selective norepinephrine reuptake inhibitor, atomoxetine, the selective serotonin reuptake inhibitor, fluoxetine, the non-sel...
Heroin intake decreases during the proestrus phase of the estrous cycle in female, Long-Evans rat... more Heroin intake decreases during the proestrus phase of the estrous cycle in female, Long-Evans rats. The purpose of this study was to (1) determine if proestrus-induced decreases in heroin intake extend across rat strains and (2) determine if proestrus-induced decreases in responding extend to a nondrug reinforcer. Female rats were implanted with intravenous catheters and trained to self-administer heroin. Estrous cycle was tracked daily for the duration of the study. During testing, Lewis, Sprague-Dawley, and Long Evans rats self-administered low (0.0025 mg/kg) and high (0.0075 mg /kg) doses of heroin (Experiment 1) and then self-administered sucrose (Experiment 2) on fixed ratio (FR1) schedules of reinforcement. Heroin intake decreased significantly during proestrus in all three rat strains under at least one dose condition; however, sucrose intake did not decrease during proestrus in any strain. These data indicate that responding maintained by heroin, but not a nondrug reinforcer...
Opioids and stimulants are often used in combination for both recreational and non-recreational p... more Opioids and stimulants are often used in combination for both recreational and non-recreational purposes. High-efficacy mu opioid agonists generally increase the behavioral effects of stimulants, whereas opioid receptor antagonists generally attenuate the behavioral effects of stimulants; however, less is known regarding the interactions between stimulants and opioids possessing low to intermediate efficacy at the mu receptor. The purpose of this study was to examine the role of an opioid's relative efficacy at the mu receptor in altering the behavioral effects of dextro(d-)amphetamine. To this end, opioids possessing a range of relative efficacy at the mu receptor were examined alone and in combination with cumulative doses of d-amphetamine on a test of open-field, locomotor activity in male rats. Levorphanol, buprenorphine, butorphanol, nalbuphine, (-)-pentazocine, (-)-metazocine, (-)-cyclazocine, (-)-NANM, and nalorphine increased the locomotor effects of d-amphetamine in eit...
2006 IEEE Southwest Symposium on Image Analysis and Interpretation
Abstract A new method for the temporal segmentation of video sequences into real-world objects is... more Abstract A new method for the temporal segmentation of video sequences into real-world objects is proposed. First, each frame undergoes a color quantization step by matching like colors extracted from the previously processed frame. JSEG's color variance feature and ...
MAIN CONCLUSION A β-ketoacyl-ACP-synthase II (KAS2) like enzyme and a lysophosphatidic acid acylt... more MAIN CONCLUSION A β-ketoacyl-ACP-synthase II (KAS2) like enzyme and a lysophosphatidic acid acyltransferase (LPAT2) from Consolida ajacis catalyze gondoic acid biosynthesis and incorporation into the sn-2 position of seed TAG in engineered Camelina sativa. Gondoic acid (cis-11 eicosenoic acid, 20:1∆11) is the predominant very-long-chain fatty acid (VLCFA) in camelina (Camelina sativa) seed oil accounting for 12-15% of total triacylglycerol fatty acids. To explore the feasibility of engineering increased levels of this fatty acid in camelina seed, oils from a range of plant species were analyzed to identify those producing 20-Carbon (C20) fatty acids as the only VLCFAs in their seed oil. Seeds of Consolida and Delphinium species (Ranunculaceae) were found to contain moderate levels (0.2% to 25.5%) of C20 fatty acids without accompanying longer chain fatty acids. The C20 fatty acids were abundant in both sn-2 and sn-1/3 positions of seed TAG in Consolida, but were largely absent from the sn-2 position in Delphinium seed TAG. Through generation of a developing seed transcriptome, sequences were identified and cDNAs amplified from Consolida ajacis encoding a β-ketoacyl-ACP-synthase II like protein (CaKAS2B) that lacked a predicted chloroplast transit peptide, and two homologues of Arabidopsis thaliana lysophosphatidic acid acyltransferase 2 (CaLPAT2a and CaLPAT2b). Expression of CaKAS2B in conventional (WT) camelina and a line previously engineered for high seed oleic acid content (HO) resulted in increased seed VLCFA content. Total VLCFA levels were raised from 24 to 35% and from 7 to 23% in T3 seed from representative transformants in the WT and HO backgrounds, respectively. Gondoic acid was the predominant VLCFA in transformed HO lines with low endogenous cytoplasmic fatty acid elongation activity, suggesting limited capacity of CaKAS2B to elongate beyond C20. Expression in camelina of CaLPAT2b resulted in significantly increased C20-VLCFA esterification at the sn-2 position of seed TAG with VLCFA levels of 33.8% in this position in one transformed line compared to 0.3% at sn-2 in the corresponding control line. Only small changes in total seed VLCFA content were observed in transformed lines implying that increased VLCFA esterification capacity in camelina results in positional redistribution of VLCFAs but does not significantly enhance flux through the fatty acid elongation pathway. The full potential of CaKAS2B and CaLPAT2a for the engineering of high gondoic acid levels in camelina remains to be determined. Seed fatty acid composition of Consolida and Delphinium also provides information that may be of value in the systematics of the Ranunculaceae.
Drug-using peers are recognized as a leading factor influencing drug use among adolescents and yo... more Drug-using peers are recognized as a leading factor influencing drug use among adolescents and young adults. One mechanism by which peers influence drug use is by providing social reinforcement for using drugs. Social reinforcement may be provided in multiple ways, including by making social contact contingent on drug use (i.e., an individual must use drugs to gain/maintain access to a peer). The purpose of this study was to develop a preclinical model in which intravenous cocaine self-administration was positively reinforced by access to a social partner. Young adult male rats were trained to self-administer cocaine in operant conditioning chambers with a guillotine door that could be opened to an adjacent compartment housing either a social partner or a non-social stimulus. Once cocaine self-administration was established, the guillotine door was activated, and cocaine intake was reinforced by brief access to either a social (age- and sex-matched peer) or non-social (black-and-whi...
Previous studies have shown that low-efficacy benzodiazepines may function as full agonists, part... more Previous studies have shown that low-efficacy benzodiazepines may function as full agonists, partial agonists or antagonists, depending upon the sensitivity of the assay to detect a drug&amp;amp;#39;s agonist effects. To date, these differential effects have only been observed across tasks, as these drugs rarely produce full agonist and antagonist effects in a single preparation. The purpose of the present study was to examine the agonist and antagonist effects of various benzodiazepines in a motor task in which the sensitivity of the task differed across conditions. To this end, rats were trained to walk on a rotorod apparatus rotating at low (4 rpm), medium (20 rpm) and high (36 rpm) speeds, and the motor-impairing effects of representative low (bretazenil), intermediate (clonazepam) and high (diazepam) efficacy benzodiazepines were examined. Diazepam and clonazepam reduced the latency for rats to fall from the rotorod at all three speeds, with both drugs being more potent at the high speed than at lower speeds. Bretazenil was also effective at decreasing motor performance at the high speed, but was not effective at lower speeds. In drug combination tests, bretazenil antagonized the effects of diazepam and clonazepam under conditions in which it was not effective when administered alone, effectively demonstrating both full agonist and antagonist effects in the same preparation. These data indicate that the sensitivity of a motor task to detect a drug&amp;amp;#39;s agonist effects can be manipulated by altering its relative level of difficulty, and that lower-efficacy benzodiazepines are more sensitive than higher-efficacy benzodiazepines to these manipulations.
In this study we used anin situapproach to identify the oxidized nucleosides 8-hydroxydeoxyguanos... more In this study we used anin situapproach to identify the oxidized nucleosides 8-hydroxydeoxyguanosine (8OHdG) and 8-hydroxyguanosine (8OHG), markers of oxidative damage to DNA and RNA, respectively, in cases of Alzheimer’s disease (AD). The goal was to determine whether nuclear and mitochondrial DNA as well as RNA is damaged in AD. Immunoreactivity with monoclonal antibodies 1F7 or 15A3 recognizing both 8OHdG and 8OHG was prominent in the cytoplasm and to a lesser extent in the nucleolus and nuclear envelope in neurons within the hippocampus, subiculum, and entorhinal cortex as well as frontal, temporal, and occipital neocortex in cases of AD, whereas similar structures were immunolabeled only faintly in controls. Relative density measurement showed that there was a significant increase (p< 0.0001) in 8OHdG and 8OHG immunoreactivity with 1F7 in cases of AD (n= 22) as compared with senile (n= 13), presenile (n= 10), or young controls (n= 4). Surprisingly, the oxidized nucleoside wa...
Development of human brain neurons The earliest stages of human brain development are very diffic... more Development of human brain neurons The earliest stages of human brain development are very difficult to monitor, but using induced pluripotent stem cells (iPSCs) can help to elucidate the process. Real et al. transplanted neural progenitors derived from human iPSCs into the brains of adult mice. They used intravital imaging to visualize how resulting neurons grew and connected. The human cells produced neurons that integrated and developed synaptic networks with oscillatory activity. Dendritic pruning was observed and involved a process of branch retraction, not degeneration. Cells derived from individuals with Down syndrome, upon transplantation into the mouse brain, produced neurons that grew normally but showed reduced dendritic spine turnover and less network activity. Science , this issue p. eaau1810
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