The effect of lithium chloride on one-trial passive avoidance learning in rats.

PubMed Central

Johnson, F N

1976-01-01

1 Expression of a one-trial passive avoidance learning response in rats was examined following injections of lithium chloride or sodium chloride before and after initial training and before the first day of testing. Five tests were given at daily intervals, 24 h after training being the time of the first test. 2. Lithium given before the first day of testing impaired response expression on the first and all subsequent days of testing; the rate of extinction was unaffected. 3. Given both before and immediately after initial training, lithium impaired response expression on the first day of testing but slowed down the subsequent rate of extinction, leading eventually to improved performance on the fifth day, as compared with placebo-treated control subjects. 4. The results are interpreted in the light of the hypothesis that lithium impaired the central processing of sensory information. PMID:1252666

Comparison between implant-supported prostheses and teeth regarding passive threshold level.

PubMed

Jacobs, R; van Steenberghe, D

1993-01-01

A passive threshold determination was carried out on 31 patients subdivided into four test groups according to different prosthesis types supported by osseointegrated implants. They were compared to a control group of 10 patients with nonrestored natural test teeth. Forces were generated by a solenoid-driven stimulating device, which was placed in contact with the implant or tooth prior to the actual force rise to avoid impact forces. The findings indicate that the threshold level of implants is 50 times higher than that of natural teeth when tapping is avoided, which might otherwise trigger distant receptors. Bone deformation triggering the periosteal mechanoreceptors is the most logical explanation for the sensation reported.

Object relations, reality testing, and social withdrawal in schizophrenia and bipolar disorder.

PubMed

Hansen, Charlotte Fredslund; Torgalsbøen, Anne-Kari; Røssberg, Jan Ivar; Romm, Kristin Lie; Andreassen, Ole Andreas; Bell, Morris D; Melle, Ingrid

2013-03-01

In this study, we investigated the relationships between observed social withdrawal (Positive and Negative Syndrome Scale [PANSS] Passive Social Withdrawal and PANSS Active Social Avoidance), subjectively experienced social withdrawal (Social Functioning Scale [SFS] Withdrawal and SFS Interpersonal Behavior), and their associations to the underlying psychological patterns of Object Relations and Reality Testing. Patients with schizophrenia (n = 55) and bipolar disorder (n = 51) from the ongoing Thematically Organized Psychosis project, Oslo University Hospital, Norway, were evaluated using the Bell Object Relations and Reality Testing Inventory, the PANSS, and the SFS. Object relations and reality testing subscales related differentially to PANSS Passive Social Withdrawal and PANSS Active Social Avoidance. These two measures, together with the level of alienation, explained a significant amount of variance in self-experienced social dysfunction. Findings reveal the multidimensional nature of social dysfunction in severe mental disorders.

Central ghrelin increases anxiety in the Open Field test and impairs retention memory in a passive avoidance task in neonatal chicks.

PubMed

Carvajal, Pedro; Carlini, Valeria P; Schiöth, Helgi B; de Barioglio, Susana R; Salvatierra, Nancy A

2009-05-01

Ghrelin (Grh) is an endogenous ligand for the growth hormone secretagogue receptor. Although Ghr stimulates feeding in rats, it inhibits feeding in neonatal chicks. However, little is known about other central behavioral effects of Ghr. Therefore, we investigated the Ghr effects, injected intracerebroventricularly, on anxiety and memory retention of neonatal chicks in an Open Field test and in a one-trial passive avoidance task, respectively. In the Open Field test, the administration of Ghr in a dose-dependent manner increased the latency to ambulate but decreased ambulation activity, indicating an anxiogenic effect. Furthermore, chicks trained on a passive avoidance task and injected with a dose of 30pmol of Ghr immediately after training showed an impairment of memory retention. However, there were no significant effects on the number of pecks during the pretraining, training, retention and discrimination. In addition, different doses of Ghr produced an inhibition in food intake at different times after injection. Our results indicate that Ghr induces anxiogenesis in chicks. Moreover, we have shown for the first time that Ghr can decrease memory retention in a non-mammalian species, suggesting that Ghr may play an important role in the processes of memory retention in birds.

Brief postnatal exposure to phenobarbital impairs passive-avoidance learning and sensorimotor gating in rats

PubMed Central

Gutherz, Samuel B.; Kulick, Catherine V.; Soper, Colin; Kondratyev, Alexei; Gale, Karen; Forcelli, Patrick A.

2014-01-01

Phenobarbital is the most commonly utilized drug for the treatment of neonatal seizures. However, mounting preclinical evidence suggests that even brief exposure to phenobarbital in the neonatal period can induce neuronal apoptosis, alterations in synaptic development, and long-lasting changes in behavioral functions. In the present report, we treated neonatal rat pups with phenobarbital and evaluated behavior in adulthood. Pups were treated initially with a loading dose (80mg/kg) on postnatal day (P)7 and with a lower dose (40 mg/kg) on P8 and P9. We examined sensorimotor gating (prepulse inhibition), passive avoidance, and conditioned place preference to cocaine when the animals reached adulthood. Consistent with our previous reports, we found that three days of neonatal exposure to phenobarbital significantly impaired prepulse inhibition as compared to vehicle-exposed control animals. Using a step-though passive avoidance paradigm, we found that animals exposed to phenobarbital as neonates and tested as adults showed significant deficits in passive avoidance retention as compared to matched controls, indicating impairment in associative memory and/or recall. Finally, we examined place preference conditioning in response to cocaine. Phenobarbital exposure did not alter the normal conditioned place preference associated with cocaine exposure. Our findings expand the profile of behavioral toxicity induced by phenobarbital. PMID:25112558

Brief postnatal exposure to phenobarbital impairs passive avoidance learning and sensorimotor gating in rats.

PubMed

Gutherz, Samuel B; Kulick, Catherine V; Soper, Colin; Kondratyev, Alexei; Gale, Karen; Forcelli, Patrick A

2014-08-01

Phenobarbital is the most commonly utilized drug for the treatment of neonatal seizures. However, mounting preclinical evidence suggests that even brief exposure to phenobarbital in the neonatal period can induce neuronal apoptosis, alterations in synaptic development, and long-lasting changes in behavioral functions. In the present report, we treated neonatal rat pups with phenobarbital and evaluated behavior in adulthood. Pups were treated initially with a loading dose (80 mg/kg) on postnatal day (P)7 and with a lower dose (40 mg/kg) on P8 and P9. We examined sensorimotor gating (prepulse inhibition), passive avoidance, and conditioned place preference for cocaine when the animals reached adulthood. Consistent with our previous reports, we found that three days of neonatal exposure to phenobarbital significantly impaired prepulse inhibition compared with vehicle-exposed control animals. Using a step-though passive avoidance paradigm, we found that animals exposed to phenobarbital as neonates and tested as adults showed significant deficits in passive avoidance retention compared with matched controls, indicating impairment in associative memory and/or recall. Finally, we examined place preference conditioning in response to cocaine. Phenobarbital exposure did not alter the normal conditioned place preference associated with cocaine exposure. Our findings expand the profile of behavioral toxicity induced by phenobarbital. Copyright © 2014 Elsevier Inc. All rights reserved.

Investigation of neuropsychopharmacological effects of a polyherbal formulation on the learning and memory process in rats.

PubMed

Shah, Js; Goyal, Rk

2011-04-01

To investigate the neuropsychopharmacological effect of a polyherbal formulation (PHF) on the learning and memory processes in rats. PHF contains Withania somnifera (Ashwagandha), Nardostachys jatamansi (Jatamansi), Rauwolfia serpentina (Sarpagandha), Evolvulus alsinoides (Shankhpushpi), Asparagus racemosus (Shatavari), Emblica officinalis (Amalki), Mucuna pruriens (Kauch bij extract), Hyoscyamus niger (Khurasani Ajmo), Mineral resin (Shilajit), Pearl (Mukta Shukhti Pishti), and coral calcium (Praval pishti). Its effect (500 mg / kg, p.o.) on the learning and memory processes was tested. The activity of PHF on memory acquisition and retention was studied using passive avoidance learning and elevated plus maze model (EPM) in rats. The animals treated with PHF showed a significant decrease in transfer latency as compared to the control group in EPM. PHF also produced significant improvement in passive avoidance acquisition and memory retrieval, as compared to the controls and reduced the latency to reach the shock free zone (SFZ) after 24 hours. The PHF produces significant improvement in passive avoidance acquisition and memory retrieval in rats, which needs further investigation.

Participation of muscarinic receptors in memory consolidation in passive avoidance learning.

PubMed

Dobryakova, Yulia V; Gurskaya, Olga; Markevich, Vladimir A

2014-01-01

It is well-known that the cholinergic system and the muscarinic cholinergic receptors are associated with cognitive functions. Here we examined whether a non-selective muscarinic receptor antagonist scopolamine affects learning performance and/or synaptic plasticity during the memory consolidation period. Adult male Wistar rats (250-300 g) were injected with scopolamine (2 mg/kg) or saline immediately after training in a "passive avoidance" task. Memory retention test was conducted 24 h after training. The changes in the latency of the first entry into a dark compartment of a test chamber was chosen as a criterion of learning. The efficacy of synaptic transmission was estimated by the changes in the basal level of focal potentials (fEPSP amplitude and slope ratio) before training (baseline), 90 min after the training (consolidation period), and 24 hour after the training (retention period). We found that foot-shock presentation by itself had no effect on fEPSP within the first 90 min after training, but in 24 hour fEPSPs were decreased. In untrained rats administration of scopolamine had no effect on the fEPSP amplitude within the first 90 min after the injection, but in 24 h we observed an increase in the fEPSP amplitude. In trained animals, scopolamine decreased the fEPSP amplitude in the hippocampal CA1 area during first 1.5 h after the injection. However, the drug had no effect on the memory retention in the passive avoidance task. Taken together our data suggest that scopolamine modifies the synaptic placticity of the hippocampal network but does not induce significant changes in the retention of the passive avoidance skill.

AMPA receptors mediate passive avoidance deficits induced by sleep deprivation.

PubMed

Dubiela, Francisco Paulino; Queiroz, Claudio Marcos; Moreira, Karin Di Monteiro; Nobrega, Jose N; Sita, Luciane Valéria; Tufik, Sergio; Hipolide, Debora Cristina

2013-11-15

The present study addressed the effects of sleep deprivation (SD) on AMPA receptor (AMPAR) binding in brain regions associated with learning and memory, and investigated whether treatment with drugs acting on AMPAR could prevent passive avoidance deficits in sleep deprived animals. [(3)H]AMPA binding and GluR1 in situ hybridization signals were quantified in different brain regions of male Wistar rats either immediately after 96 h of sleep deprivation or after 24h of sleep recovery following 96 h of sleep deprivation. Another group of animals were sleep deprived and then treated with either the AMPAR potentiator, aniracetam (25, 50 and 100mg/kg, acute administration) or the AMPAR antagonist GYKI-52466 (5 and 10mg/kg, acute and chronic administration) before passive avoidance training. Task performance was evaluated 2h and 24h after training. A significant reduction in [(3)H]AMPA binding was found in the hippocampal formation of SD animals, while no alterations were observed in GluR1 mRNA levels. The highest dose of aniracetam (100mg/kg) reverted SD-induced impairment of passive avoidance performance in both retention tests, whereas GYKI-52466 treatment had no effect. Pharmacological enhancement of AMPAR function may revert hippocampal-dependent learning impairments produced after SD. We argue that such effects might be associated with reduced AMPAR binding in the hippocampus of sleep deprived animals. Copyright © 2013 Elsevier B.V. All rights reserved.

The effect of Vitamin E on learning and memory deficits in intrahippocampal kainate-induced temporal lobe epilepsy in rats.

PubMed

Kiasalari, Zahra; Khalili, Mohsen; Shafiee, Samaneh; Roghani, Mehrdad

2016-01-01

Since temporal lobe epilepsy (TLE) is associated with learning and memory impairment, we investigated the beneficial effect of Vitamin E on the impaired learning and memory in the intrahippocampal kainate model of TLE in rats. Rats were divided into sham, Vitamin E-treated sham, kainate, and Vitamin E-treated kainate. Intrahippocampal kainate was used for induction of epilepsy. Vitamin E was injected intraperitoneal (i.p.) at a dose of 200 mg/kg/day started 1 week before surgery until 1 h presurgery. Initial and step-through latencies in the passive avoidance test and alternation behavior percentage in Y-maze were finally determined in addition to measurement of some oxidative stress markers. Kainate injection caused a higher severity and rate of seizures and deteriorated learning and memory performance in passive avoidance paradigm and spontaneous alternation as an index of spatial recognition memory in Y-maze task. Intrahippocampal kainate also led to the elevation of malondialdehyde (MDA) and nitrite and reduced activity of superoxide dismutase (SOD). Vitamin E pretreatment significantly attenuated severity and incidence rate of seizures, significantly improved retrieval and recall in passive avoidance, did not ameliorate spatial memory deficit in Y-maze, and lowered MDA and enhanced SOD activity. Vitamin E improves passive avoidance learning and memory and part of its beneficial effect is due to its potential to mitigate hippocampal oxidative stress.

Investigation of Neuropsychopharmacological Effects of a Polyherbal Formulation on the Learning and Memory Process in Rats

PubMed Central

Shah, JS; Goyal, RK

2011-01-01

Objective: To investigate the neuropsychopharmacological effect of a polyherbal formulation (PHF) on the learning and memory processes in rats. Materials and Methods: PHF contains Withania somnifera (Ashwagandha), Nardostachys jatamansi (Jatamansi), Rauwolfia serpentina (Sarpagandha), Evolvulus alsinoides (Shankhpushpi), Asparagus racemosus (Shatavari), Emblica officinalis (Amalki), Mucuna pruriens (Kauch bij extract), Hyoscyamus niger (Khurasani Ajmo), Mineral resin (Shilajit), Pearl (Mukta Shukhti Pishti), and coral calcium (Praval pishti). Its effect (500 mg / kg, p.o.) on the learning and memory processes was tested. The activity of PHF on memory acquisition and retention was studied using passive avoidance learning and elevated plus maze model (EPM) in rats. Results: The animals treated with PHF showed a significant decrease in transfer latency as compared to the control group in EPM. PHF also produced significant improvement in passive avoidance acquisition and memory retrieval, as compared to the controls and reduced the latency to reach the shock free zone (SFZ) after 24 hours. Conclusion: The PHF produces significant improvement in passive avoidance acquisition and memory retrieval in rats, which needs further investigation. PMID:21731356

Passive Avoidance Training and Recall are Associated With Increased Glutamate Levels in the Intermediate Medial Hyperstriatum Ventrale of the Day-Old Chick

PubMed Central

Daisley, Jonathan N.; Gruss, Michael; Rose, Steven P. R.; Braun, Katharina

1998-01-01

In the young chick, the intermediate medial hyperstriatum ventrale is involved in learning paradigms, including imprinting and passive avoidance learning. Biochemical changes in the intermediate medial hyperstriatum ventrale following learning include an up-regulation of amino-acid transmitter levels and receptor activity. To follow the changes of extracellular amino acid levels during passive avoidance training, we used an in vivo microdialysis technique. Probes were implanted in chicks before training the animals, either on a methyl- anthranylate-or water-coated bead. One hour later, recall was tested in both groups by presenting a similar bead. An increase of extra-cellular glutamate levels accompanied training and testing in both groups; during training, glutamate release was higher in methylanthranylate- trained than in water-trained chicks. When compared with the methylanthranylate-trained chicks during testing, the water-trained chicks showed enhanced extra-cellular glutamate levels. No other amino acid examined showed significant changes. After testing, the chicks were anesthetized and release- stimulated with an infusion of 50 mM potassium. Extra-cellular glutamate and taurine levels were significantly increased in both methylanthranylate-and water-trained chicks. The presentation of methylanthranylate as an. olfactory stimulus significantly enhanced glutamate levels, especially in methylanthranylate-trained chicks. The results suggest that such changes in extra-cellular glutamate levels in the intermediate medial hyperstriatum ventrale accompany pecking at either the water- or the methylanthranylate-bead. The taste of the aversant may be responsible for the greater increases found in methylanthranylate-trained birds. PMID:9920682

Effect of radio-frequency electromagnetic radiations (RF-EMR) on passive avoidance behaviour and hippocampal morphology in Wistar rats.

PubMed

Narayanan, Sareesh Naduvil; Kumar, Raju Suresh; Potu, Bhagath Kumar; Nayak, Satheesha; Bhat, P Gopalakrishna; Mailankot, Maneesh

2010-05-01

The interaction of mobile phone radio-frequency electromagnetic radiation (RF-EMR) with the brain is a serious concern of our society. We evaluated the effect of RF-EMR from mobile phones on passive avoidance behaviour and hippocampal morphology in rats. Healthy male albino Wistar rats were exposed to RF-EMR by giving 50 missed calls (within 1 hour) per day for 4 weeks, keeping a GSM (0.9 GHz/1.8 GHz) mobile phone in vibratory mode (no ring tone) in the cage. After the experimental period, passive avoidance behaviour and hippocampal morphology were studied. Passive avoidance behaviour was significantly affected in mobile phone RF-EMR-exposed rats demonstrated as shorter entrance latency to the dark compartment when compared to the control rats. Marked morphological changes were also observed in the CA(3) region of the hippocampus of the mobile phone-exposed rats in comparison to the control rats. Mobile phone RF-EMR exposure significantly altered the passive avoidance behaviour and hippocampal morphology in rats.

Flight data acquisition methodology for validation of passive ranging algorithms for obstacle avoidance

NASA Technical Reports Server (NTRS)

Smith, Phillip N.

1990-01-01

The automation of low-altitude rotorcraft flight depends on the ability to detect, locate, and navigate around obstacles lying in the rotorcraft's intended flightpath. Computer vision techniques provide a passive method of obstacle detection and range estimation, for obstacle avoidance. Several algorithms based on computer vision methods have been developed for this purpose using laboratory data; however, further development and validation of candidate algorithms require data collected from rotorcraft flight. A data base containing low-altitude imagery augmented with the rotorcraft and sensor parameters required for passive range estimation is not readily available. Here, the emphasis is on the methodology used to develop such a data base from flight-test data consisting of imagery, rotorcraft and sensor parameters, and ground-truth range measurements. As part of the data preparation, a technique for obtaining the sensor calibration parameters is described. The data base will enable the further development of algorithms for computer vision-based obstacle detection and passive range estimation, as well as provide a benchmark for verification of range estimates against ground-truth measurements.

Neuroprotective and cognitive enhancing activity of the fermented Bozhougyiqi-Tang

PubMed Central

Weon, Jin Bae; Lee, Bohyoung; Yun, Bo-Ra; Lee, Jiwoo; Ma, Jin Y; Ma, Choong Je

2014-01-01

Background: Alzheimer's disease is a neurodegenerative disease related to memory impairments and neuronal cell death. Bozhougyiqi-Tang (BZYQT), a traditional herbal medicine, has been therapeutically used for the treatment of pulmonary tuberculosis. Objective: The aim of this study is to evaluated the neuroprotective effect of the fermented BZYQT and compared with unfermented BZYQT in HT22 cells by MTT assay and tested the beneficial effect on memory impairments induced by scopolamine (1 mg/kg, i.p.) using the passive avoidance and Morris water maze tests. Results: Compared with unfermented BZYQT, the neuroprotective effect of fermented BZYQT on glutamate induced neurotoxicity in HT22 cells increased at a concentration of 100 μg/mL. Fermented BZYQT increased the step-through latency of the passive avoidance response. Furthermore, in Morris water maze test for evaluation of spatial learning and memory, escape latency time was significantly reduced by fermented BZYQT. Conclusion: These results suggest that the fermentation process of BZYQT led to improve neuroprotective and cognitive enhancing effect. PMID:24991099

Effects of aniracetam on one-trial passive avoidance tests and cholinergic neurons in discrete brain regions of rats.

PubMed

Toide, K

1989-01-01

Using rats in one-trial passive avoidance tests, the anti-amnesic effects of the nootropic drug aniracetam were investigated; moreover, the action of aniracetam upon the cholinergic system in the brain was studied. In one-trial passive avoidance tests, aniracetam prolonged significantly the retention time for 100 mg/kg, p.o. However, the retention-prolonging effect was diminished when the dose was increased to 300 mg/kg p.o. Investigation of the action of the drug upon the cholinergic system revealed that ACh and choline content in the corpus striatum was not increased by any doses of aniracetam. ACh content in the hippocampus was increased by doses of 100-300 mg/kg, p.o., but choline was not significantly increased by any doses, while in the cerebral cortex ACh content was significantly increased by a dose of 300 mg/kg, p.o. In addition, the decrease in hippocampal ACh and choline content following an injection of scopolamine was lessened by aniracetam 100 mg/kg, p.o. and 100-300 mg/kg, respectively. In order to elucidate the mechanism of these actions of aniracetam, the ACh-releasing action and changes in choline content of the extracellular spaces in the hippocampus were investigated, but no effects were observed. The results obtained indicate that aniracetam has an inhibitory effect upon scopolamine-induced amnesia. The mechanism of this effect may be an action upon the cholinergic system; therefore, some action with respect to the impairment of cholinergic neurotransmission in the hippocampus induced by scopolamine appears to be of particular importance.

[Influence of activation and blockade of NMDA receptors on extinction of passive avoidance response in mice with different levels of anxiety].

PubMed

Tomilenko, R A; Dubrovina, N I

2006-03-01

Influence of agonist (D-cycloserine) and antagonist (dizocilpine) N-methyl-D-aspartate receptors on learning and extinction of passive avoidance response in medium-, high-, and low-anxious mice was studied. In medium-anxious mice, D-cycloserine (30 mg/kg) although not changing learning accelerated development of extinction, whereas dizocilpine (0.15 mg/kg), while impairing passive avoidance learning, detained the extinction. In high-anxious mice with good retrieval of memory trace and absence of extinction, D-cycloserine was ineffective, whereas dizocilpine reduced learning and promoted retention of memory trace retrieval at the generated level on extinction. In low-anxious mice, D-cycloserine impaired learning and accelerated extinction, whereas dizocilpine completely blocked learning and retention of passive avoidance response.

CHARACTER OF THE CHANGES IN FEAR MOTIVATED DECLARATIVE MEMORY IN THE HIGH IMMOBILIZATION "DEPRESSIVE" RATS.

PubMed

Nachkebia, N; Shavgulidze, M; Babilodze, M; Chkhartishvili, E; Rogava, N

2016-10-01

Present study investigated possible differences in the learning and memory of declarative memory task in rats selected according to the differences in immobilization response that is in high immobilization "depressive" and low immobilization "non-depressive" rats. Understanding the character of learning and memory disturbances in basal conditions of animal models of depression is still very topical for more intimate definition of the pathophysiology of major depressive disorder and appropriate searching the ways of its correction. Experiments were carried out on the adult white wild rats (with the weight 200-250 g, n=20). Selection of rats according to the level of immobilization was made by means of forced swim test. Learning and memory disturbances were studied using passive avoidance test that is fear motivated one trial declarative memory task. It was shown by us that 100% of low immobilization "non-depressive" rats remember painful stimulation and therefore they are not enter in the dark compartment during whole period of observation during testing session. Behavior of high immobilization "depressive" rats is not similar in passive avoidance camera; 50% of "depressive" rats, with long escape latency during training session (92±10 sec), remember painful stimulation during testing session and therefore they are not enter in the dark compartment during whole observation period. The remaining 50%, that are not differ significantly from the low immobility "non-depressive" rats by the latency of escape (5±1 sec) during training session, are not able to remember painful stimulation during testing session and therefore they enter in the dark compartment with shortest escape latency (6±1 sec). In conclusion, high immobility "depressive" rats perform passive avoidance declarative memory task at the chance level that is a direct indicator for the serious disturbances of declarative memory mechanisms in "depressive" rats selected in forced swim test according to the level of immobility.

Potentiation of the early visual response to learned danger signals in adults and adolescents

PubMed Central

Howsley, Philippa; Jordan, Jeff; Johnston, Pat

2015-01-01

The reinforcing effects of aversive outcomes on avoidance behaviour are well established. However, their influence on perceptual processes is less well explored, especially during the transition from adolescence to adulthood. Using electroencephalography, we examined whether learning to actively or passively avoid harm can modulate early visual responses in adolescents and adults. The task included two avoidance conditions, active and passive, where two different warning stimuli predicted the imminent, but avoidable, presentation of an aversive tone. To avoid the aversive outcome, participants had to learn to emit an action (active avoidance) for one of the warning stimuli and omit an action for the other (passive avoidance). Both adults and adolescents performed the task with a high degree of accuracy. For both adolescents and adults, increased N170 event-related potential amplitudes were found for both the active and the passive warning stimuli compared with control conditions. Moreover, the potentiation of the N170 to the warning stimuli was stable and long lasting. Developmental differences were also observed; adolescents showed greater potentiation of the N170 component to danger signals. These findings demonstrate, for the first time, that learned danger signals in an instrumental avoidance task can influence early visual sensory processes in both adults and adolescents. PMID:24652856

The Effect of BSA-Based Curcumin Nanoparticles on Memory and Hippocampal MMP-2, MMP-9, and MAPKs in Adult Mice.

PubMed

SoukhakLari, Roksana; Moezi, Leila; Pirsalami, Fatema; Moosavi, Maryam

2018-06-24

Although high rate of curcumin consumption has been suggested to decrease the prevalence of Alzheimer's disease (AD), its administration has no effect on the progression of AD in humans and this has been attributed to its poor bioavailability. Using nanotechnology to break down curcumin increases its bioavailability and improves its effect on the brain. BSA, as a non-toxic protein with high binding capacity, was used to break curcumin to nanosize and to explore the effect of nanocurcumin on passive avoidance memory and hippocampal MMP-2 and -9 and MAPKs. BSA-based nanocurcumin was produced by desolvation method. In this study, 15 and 20 mg/kg/p.o. nanocurcumin (based on our preliminary studies) were administered to male NMRI mice weighing 20-25 g for 10 days. Passive avoidance training was performed on day 10 and 24 h after, a retention trial was done. Upon completion of behavioral studies, the hippocampi were isolated and western blot analysis was performed on MMP-2, MMP-9, and MAPKs (JNK, ERK, and p38). The results showed that BSA-based nanocurcumin administered at 15 and 20 mg/kg doses resulted in a significantly improved performance in passive avoidance memory test while its equivalent doses of natural curcumin did not produce a similar effect. In addition, this effect was accompanied with an increase in MMP-2, MMP-9, and p-ERK and a decrease in p-JNK. This study indicates that breaking curcumin to nanosize produces improved effects on passive avoidance memory in adult mice accompanied with MMP-2, MMP-9, p-ERK, and p-JNK changes in the hippocampus.

Prolongation of latencies for passive avoidance responses in rats treated with aniracetam or piracetam.

PubMed

Yamada, K; Inoue, T; Tanaka, M; Furukawa, T

1985-04-01

Effects of aniracetam (1-anysoyl-2-pyrrolodone) and piracetam (1-acetamido-2-pyrrolidone) on passive avoidance behavior were studied in 2 and 18 months old rats using a step-down passive avoidance task. Repeated administration of aniracetam (30 and 50 mg/kg, IP X 5 days) or piracetam (100 mg/kg, IP X 5 days) significantly prolonged step-down latencies for a passive avoidance task in 2 months old rats. Administration of aniracetam (50 mg/kg, IP) or piracetam (100 mg/kg, IP), however, did not affect locomotor activity. This prolongation of latencies was also seen with oral administration of aniracetam (50 mg/kg X 5 days). Similar prolongation of latencies also occurred in 18 months old rat treated with aniracetam (50 mg/kg, IP X 5 days). The results imply that aniracetam may improve learning and/or memory in 2 and 18 months old rats.

Cross State-dependent Learning Interaction Between Scopolamine and Morphine in Mice: The Role of Dorsal Hippocampus

PubMed Central

Maleki, Morteza; Hassanpour-Ezatti, Majid; Navaeian, Majid

2017-01-01

Introduction: The current study aimed at investigating the existence of the cross state-dependent learning between morphine and scopolamine (SCO) in mice by passive avoidance method, pointing to the role of CA1 area. Methods: The effects of pre-training SCO (0.75, 1.5, and 3 μg, Intra-CA1), or morphine (1, 3, and 6 mg/kg, intraperitoneal (i.p.) was evaluated on the retrieval of passive avoidance learning using step-down task in mice (n=10). Then, the effect of pretest administration of morphine (1.5, 3, and 6 mg/kg, i.p.) was examined on passive avoidance retrieval impairment induced by pre-training SCO (3 μg/mice, Intra-CA1). Next, the effect of pretest Intra-CA1 injection of scopolamine (0.75, 1.5, and 3 μg/mice) was evaluated on morphine (6 mg/kg, i.p.) pre-training deficits in this task in mice. Results: The pre-training Intra-CA1 injection of scopolamine (1.5 and 3 μg/mouse), or morphine (3 and 6 mg/kg, i.p.) impaired the avoidance memory retrieval when it was tested 24 hours later. Pretest injection of both drugs improved its pre-training impairing effects on mice memory. Moreover, the amnesia induced by the pre-training injections of scopolamine (3 μg/mice) was restored significantly (P<0.01) by pretest injections of morphine (3 and 6 mg/kg, i.p.). Similarly, pretest injection of scopolamine (3 μg/mice) restored amnesia induced by the pre-training injections of morphine (6 mg/kg, i.p.), significantly (P<0.01). Conclusion: The current study findings indicated a cross state-dependent learning between SCO and morphine at CA1 level. Therefore, it seems that muscarinic and opioid receptors may act reciprocally on modulation of passive avoidance memory retrieval, at the level of dorsal hippocampus, in mice. PMID:28781727

Ameliorative effect of Noni fruit extract on streptozotocin-induced memory impairment in mice.

PubMed

Pachauri, Shakti D; Verma, Priya Ranjan P; Dwivedi, Anil K; Tota, Santoshkumar; Khandelwal, Kiran; Saxena, Jitendra K; Nath, Chandishwar

2013-08-01

This study evaluated the effects of a standardized ethyl acetate extract of Morinda citrifolia L. (Noni) fruit on impairment of memory, brain energy metabolism, and cholinergic function in intracerebral streptozotocin (STZ)-treated mice. STZ (0.5 mg/kg) was administered twice at an interval of 48 h. Noni (50 and 100 mg/kg, postoperatively) was administered for 21 days following STZ administration. Memory function was evaluated using Morris Water Maze and passive avoidance tests, and brain levels of cholinergic function, oxidative stress, energy metabolism, and brain-derived neurotrophic factor (BDNF) were estimated. STZ caused memory impairment in Morris Water Maze and passive avoidance tests along with reduced brain levels of ATP, BDNF, and acetylcholine and increased acetylcholinesterase activity and oxidative stress. Treatment with Noni extract (100 mg/kg) prevented the STZ-induced memory impairment in both behavioral tests along with reduced oxidative stress and acetylcholinesterase activity, and increased brain levels of BDNF, acetylcholine, and ATP level. The study shows the beneficial effects of Noni fruit against STZ-induced memory impairment, which may be attributed to improved brain energy metabolism, cholinergic neurotransmission, BDNF, and antioxidative action.

The effect of para-chlorophenylalanine and scopolamine on passive avoidance in chicks.

PubMed

Mattingly, B A; Zolman, J F

1981-05-01

Four-day-old Vantress x Arbor Acre chicks were treated for key-peck passive avoidance (PA) learning following intraperitoneal injections of parachlorophenylalanine (PCPA) and/or scopolamine. In Experiment 1, chicks were pre-treated with either three or five injections of PCPA (150 mg/kg) or saline across th first three posthatch days and then tested for PA learning on the fourth posthatch day. In Experiment 2, chicks were first pre-treated with three injections of PCPA (150 mg/kg) or saline, and then injected with either scopolamine (0.5 mg/kg) or saline 20 min prior to PA testing on the fourth posthatch day. Major findings were: (a) Chicks pre-treated with PCPA did not significantly differ from saline control chicks in either the acquisition or maintenance of response suppression during PA testing; (b) chicks injected with scopolamine were significantly disrupted in PA learning as compared to saline control chicks; and (c) PCPA pre-treatment did not significantly affect the scopolamine-induced disruption of PA learning. These findings, therefore, suggest that cholinergic, but not serotonergic, mechanisms are involved in PA learning of the young chick.

[Delayed reactions of active avoidance in white rats under conditions of an alternative choice].

PubMed

Ioseliani, T K; Sikharulidze, N I; Kadagishvili, A Ia; Mitashvili, E G

1995-01-01

It was shown that if the rats had been learned and then tested using conventional pain punishment of erroneous choice they were able to solve the problem of alternative choice only in the period of immediate action of conditioned stimuli. If the pain punishment for erroneously chosen compartment had not been applied in animal learning and testing, rats successfully solved the problem of alternative choice even after 5-second delay. Introduction of pain punishment led to the frustration of earlier elaborated delayed avoidance reactions. Analysis of the obtained results allows us to argue that the apparent incapability of white rats for solving the problems of delayed avoidance is caused by simultaneous action of two different mechanisms, i.e., those of the active and passive avoidance rather than short-term memory deficit.

Nootropic activity of Celastrus paniculatus seed.

PubMed

Bhanumathy, M; Harish, M S; Shivaprasad, H N; Sushma, G

2010-03-01

The effect of Celastrus paniculatus Willd. (Celastraceae) seed aqueous extract on learning and memory was studied using elevated plus maze and passive avoidance test (sodium nitrite induced amnesia rodent model). The aqueous seed extract was administered orally in two different doses to rats (350 and 1050 mg/kg) and to mice (500 and 1500 mg/kg). The results were compared to piracetam (100 mg/kg, p.o.) used as a standard drug. Chemical hypoxia was induced by subcutaneous administration of sodium nitrite (35 mg/kg), immediately after acquisition training. In elevated plus maze and sodium nitrite-induced amnesia model, Celastrus paniculatus extract has showed statistically significant improvement in memory process when compared to control. The estimation of acetylcholinesterase enzyme in rat brain supports the plus maze and passive avoidance test by reducing acetylcholinesterase activity which helps in memory performance. The study reveals that the aqueous extract of Celastrus paniculatus seed has dose-dependent cholinergic activity, thereby improving memory performance. The mechanism by which Celastrus paniculatus enhances cognition may be due to increased acetylcholine level in rat brain.

Ameliorating effect of new constituents from the hooks of Uncaria rhynchophylla on scopolamine-induced memory impairment.

PubMed

Shin, Suk-Chul; Lee, Dong-Ung

2013-07-01

To study the chemical constituents and their anti-amnesic effect from the hooks of Uncaria rhynchophylla. The isolation of compounds was performed by chromatographic techniques and their structures were identified on the basis of spectral analysis. Their ameliorating effects on scopolamine-induced memory impairment in vivo using a Morris water-maze task and passive avoidance task system were evaluated. Activity-guided fractionation of the total extracts resulted in the isolation of four constituents, trans-anethole (1), p-anisaldehyde (2), estragole (3), and 3-oxo-olean-12-en-28-oic acid (4), which were found for the first time from this plant. Compound 1 exhibited a better memory enhancing effect than tacrine, a positive agent, at the same dose in the passive avoidance test and a similar property in the water-maze test, and its action may be mediated, in part, by the acetylcholine enhancing cholinergic nervous system. Copyright © 2013 China Pharmaceutical University. Published by Elsevier B.V. All rights reserved.

Corrosion control when using passively treated abandoned mine drainage as alternative makeup water for cooling systems.

PubMed

Hsieh, Ming-Kai; Chien, Shih-Hsiang; Li, Heng; Monnell, Jason D; Dzombak, David A; Vidic, Radisav D

2011-09-01

Passively treated abandoned mine drainage (AMD) is a promising alternative to fresh water as power plant cooling water system makeup water in mining regions where such water is abundant. Passive treatment and reuse of AMD can avoid the contamination of surface water caused by discharge of abandoned mine water, which typically is acidic and contains high concentrations of metals, especially iron. The purpose of this study was to evaluate the feasibility of reusing passively treated AMD in cooling systems with respect to corrosion control through laboratory experiments and pilot-scale field testing. The results showed that, with the addition of the inhibitor mixture orthophosphate and tolyltriazole, mild steel and copper corrosion rates were reduced to acceptable levels (< 0.127 mm/y and < 0.0076 mm/y, respectively). Aluminum had pitting corrosion problems in every condition tested, while cupronickel showed that, even in the absence of any inhibitor and in the presence of the biocide monochloramine, its corrosion rate was still very low (0.018 mm/y).

TRIMETHYLTIN IMPAIRS RETENTION OF A PASSIVE AVOIDANCE TASK

EPA Science Inventory

Trimethyltin is a neurotoxic organometal which produces neuronal damage in several limbic regions including the hippocampus, amygdala and the pyriform cortex. One administration of trimethyltin (5,6 or 7 mg/kg) twenty one days prior to passive avoidance conditioning produced an i...

Divergent stress responses and coping styles in psychogenetically selected Roman high-(RHA) and low-(RLA) avoidance rats: behavioural, neuroendocrine and developmental aspects.

PubMed

Steimer, Thierry; Driscoll, Peter

2003-06-01

The Swiss sublines of Roman high-(RHA/Verh) and low-(RLA/Verh) avoidance rats have been genetically selected for good vs. poor performance in two-way active avoidance since 1972. RLA/Verh rats show increased stress responses (e.g. freezing behaviour, ACTH, corticosterone and prolactin secretion) and adopt a more passive (or reactive) coping style when confronted with a novel environment. In the open field, elevated plus-maze, black/white box test, and in a new light/dark open field test, RLA/Verh rats appear to be more anxious than their RHA/Verh counterparts. Anxiety may result from their particular psychophysiological profile, i.e. increased emotionality combined with a passive coping style. In contrast, RHA/Verh rats are less responsive to stress, they show little anxiety in novel situations and tend to be impulsive and novelty (sensation) seekers. Some behavioural differences are already noticeable shortly after birth, but the full pattern appears to stabilize only after puberty. Gene-environment interactions are critical in establishing this pattern. The data reviewed indicate that the differences between RHA/Verh and RLA/Verh rats probably result from a complex interaction among divergent anxiety/emotionality characteristics, differences in locomotor activity and novelty/reward seeking, as well as active vs. passive coping styles. It is proposed further that these divergent personality types are to be found not only in other selective breeding programs but in the form of individual differences in most populations of rats used for this type of research.

Enhanced Cognitive Effects of Demethoxycurcumin, a Natural Derivative of Curcumin on Scopolamine-Induced Memory Impairment in Mice.

PubMed

Lim, Dong Wook; Son, Hyun Jung; Um, Min Young; Kim, In-Ho; Han, Daeseok; Cho, Suengmok; Lee, Chang-Ho

2016-08-05

In the present study, we examined the ameliorating effects of demethoxycurcumin (DMC) on memory impairment induced by scopolamine using passive avoidance and Morris water maze tests in mice. Moreover, to determine the neurobiological effects underlying the ameliorating effects of the DMC, choline acetyltransferase (ChAT) immunoreactivity was evaluated in mice exposed to scopolamine. Our results demonstrated that chronic oral administration (28 days) of DMC (10 mg/kg) improved scopolamine-induced learning impairment in the passive avoidance task and memory impairment in the Morris water maze. Moreover, Choline acetyltransferase (ChAT) activity in the DMC-treated group was significantly increased to 33.03% compared with the control group. Our present finding suggests that DMC ameliorates memory impairments induced by scopolamine treatment through reversing the reduction of hippocampal ChAT expression in mice.

Learning and extinction of a passive avoidance response in mice with high levels of predisposition to catalepsy.

PubMed

Dubrovina, N I; Zinov'ev, D R; Zinov'eva, D V; Kulikov, A V

2009-06-01

This report presents results obtained from comparative analysis of learning and the dynamics of extinction of a conditioned passive avoidance response in ASC mice, which were bred for a high level of predisposition to catalepsy, and in CBA and AKR mice. The following findings were obtained: 1) impairments to the extinction of the memory of fear represent an important symptom of depression in ASC mice; 2) extinction is delayed in CBA mice; and 3) new inhibitory learning occurs quickly in AKR mice. Prolonged retention of the fear memory in ASC mice appears to be related to increased anxiety on prolonged testing without a punishment. The deficit of inhibition of the fear reaction in ASC mice allows this strain to be regarded as a genetic model of depression.

Sense and avoid technology for Global Hawk and Predator UAVs

NASA Astrophysics Data System (ADS)

McCalmont, John F.; Utt, James; Deschenes, Michael; Taylor, Michael J.

2005-05-01

The Sensors Directorate at the Air Force Research Laboratory (AFRL) along with Defense Research Associates, Inc. (DRA) conducted a flight demonstration of technology that could potentially satisfy the Federal Aviation Administration's (FAA) requirement for Unmanned Aerial Vehicles (UAVs) to sense and avoid local air traffic sufficient to provide an "...equivalent level of safety, comparable to see-and-avoid requirements for manned aircraft". This FAA requirement must be satisfied for autonomous UAV operation within the national airspace. The real-time on-board system passively detects approaching aircraft, both cooperative and non-cooperative, using imaging sensors operating in the visible/near infrared band and a passive moving target indicator algorithm. Detection range requirements for RQ-4 and MQ-9 UAVs were determined based on analysis of flight geometries, avoidance maneuver timelines, system latencies and human pilot performance. Flight data and UAV operating parameters were provided by the system program offices, prime contractors, and flight-test personnel. Flight demonstrations were conducted using a surrogate UAV (Aero Commander) and an intruder aircraft (Beech Bonanza). The system demonstrated target detection ranges out to 3 nautical miles in nose-to-nose scenarios and marginal visual meteorological conditions. (VMC) This paper will describe the sense and avoid requirements definition process and the system concept (sensors, algorithms, processor, and flight rest results) that has demonstrated the potential to satisfy the FAA sense and avoid requirements.

Tobacco Use and Environmental Smoke Exposure among Taiwanese Pregnant Smokers and Recent Quitters: Risk Perception, Attitude, and Avoidance Behavior

PubMed Central

Lai, Ming-Cheng; Chou, Feng-Sha; Yang, Yann-Jy; Wang, Chih-Chien; Lee, Ming-Chang

2013-01-01

In this study, we conducted an empirical survey of the avoidance behaviors and risk perceptions of active and passive smoking pregnant smokers and recent quitters. We employed an online questionnaire survey by recruiting 166 voluntary participants from an online parenting community in Taiwan. The results of the empirical survey revealed that three-fourths of smokers quit smoking during pregnancy and one-fourth continued smoking. All pregnant women who continued smoking had partners or lived with relatives who smoked. Current smokers and quitters differed significantly in their risk perceptions and attitudes toward smoking during pregnancy. Most pregnant smokers and quitters adopted passive smoking avoidance behaviors at home and in public. Nevertheless, one-fifth of pregnant women chose not to avoid passive smoking. We concluded that most women stop smoking during pregnancy; however, most women continue to be exposed to passive-smoking environments. Perceived fetal health risks and attitudes toward smoking during pregnancy are critical predictors of the anti-smoking behaviors of pregnant women. PMID:24005830

Behavioral Strategies for Nonsmokers: Avoiding and Confronting Smokers.

ERIC Educational Resources Information Center

Jason, Leonard A.

Nonsmokers repeatedly breathe smoke-polluted air in various settings, despite the evidence demonstrating the deleterious consequences upon such passive smokers. The extent of exposure to environmental irritants during a 17-day baseline period was tested, and the efficacy of two simple behavioral strategies in reducing smoke were documented…

P7C3 Attenuates the Scopolamine-Induced Memory Impairments in C57BL/6J Mice.

PubMed

Jiang, Bo; Song, Lu; Huang, Chao; Zhang, Wei

2016-05-01

Memory impairment is the most common symptom in patients with Alzheimer's disease. The purpose of this study is to evaluate the memory enhancing effects of P7C3, a recently identified compound with robust proneurogenic and neuroprotective effects, on the cognitive impairment induced by scopolamine, a muscarinic acetylcholine receptor antagonist. Different behavior tests including the Y-maze, Morris water maze, and passive avoidance tests were performed to measure cognitive functions. Scopolamine significantly decreased the spontaneous alternation and step-through latency of C57BL/6J mice in Y-maze test and passive avoidance test, whereas increased the time of mice spent to find the hidden platform in Morris water maze test. Importantly, intraperitoneal administration of P7C3 effectively reversed those Scopolamine-induced cognitive impairments in C57BL/6J mice. Furthermore, P7C3 treatment significantly enhanced the level of brain-derived neurotrophic factor (BDNF) signaling pathway in the cortex and hippocampus, and the usage of selective BDNF signaling inhibitor fully blocked the anti-amnesic effects of P7C3. Therefore, these findings suggest that P7C3 could improve the scopolamine-induced learning and memory impairment possibly through activation of BDNF signaling pathway, thereby exhibiting a cognition-enhancing potential.

Acute Effects of Ecstasy on Memory Are more Extensive than Chronic Effects.

PubMed

Shariati, Mohamad Bakhtiar Hesam; Sohrabi, Maryam; Shahidi, Siamak; Nikkhah, Ali; Mirzaei, Fatemeh; Medizadeh, Mehdi; Asl, Sara Soleimani

2014-01-01

Exposure to 3, 4- methylenedioxymethamphetamine (MDMA) could lead to serotonergic system toxicity in the brain. This system is responsible for learning and memory functions. Studies show that MDMA causes memory impairment dose-dependently and acutely. The present study was designed to evaluate the chronic and acute effects of MDMD on spatial memory and acquisition of passive avoidance. Adult male Wistar rats (200-250 g) were given single or multiple injections of MDMA (10 mg/kg, IP). Using passive avoidance and Morris Water Maze (MWM) tasks, learning and spatial memory functions were assessed. The data were analyzed by SPSS 16 software and one- way analysis of variance (ANOVA) test. Our results showed that there were significant differences in latency to enter the dark compartment (STL) between sham and MDMA- treated groups. Acute group significantly showed more STL in comparison with chronic group. Furthermore, MDMA groups spent more time in dark compartment (TDS) than the sham group. Administration of single dose of MDMA significantly caused an increase in TDS compared with the chronic group. In the MWM, MDMA treatment significantly increased the traveled distance and escaped latency compared to the sham group. Like to passive avoidance task, percentage of time spent in the target quadrant in MDMA- treated animals impaired in MWM compared with sham group. These data suggest that MDMA treatment impairs learning and memory functions that are more extensive in acute- treated rats.

Effects of repeated administration of (-)-nicotine on AF64A-induced learning and memory impairment in rats.

PubMed

Hiramatsu, M; Yamatsu, T; Kameyama, T; Nabeshima, T

2002-03-01

It has been reported that pretreatment with (-)-nicotine prevents glutamate- and amyloid beta protein (Abeta)-induced cytotoxicity in vitro. However, few studies on the neuroprotective effects of (-)-nicotine in vivo have been reported. We examined whether repeated administration of (-)-nicotine exhibits neuroprotective effects in AF64A-treated rats. (-)-Nicotine (0.1 and 0.2 mg/kg, s.c.) was administered once a day for 28 days. On day 14, AF64A (2.5 nmol/side) was injected bilaterally into the hippocampus. Intrahippocampal injection of AF64A showed severe impairment of learning and memory in rats in the water maze and passive avoidance tests. Repeated administration of (-)-nicotine (0.1 and 0.2 mg/kg, s.c.) did not reverse the impairment of memory induced by AF64A in the water maze test. Interestingly, the (-)-nicotine (0.1 and 0.2 mg/kg, s.c.)-treated group showed weak impairment of learning and memory after AF64A treatment compared to the (AF64A + saline)-treated group in the passive avoidance test. These results suggested that (-)-nicotine may have neuroprotective effects against the neurotoxicity induced by AF64A.

Comparison of Nootropic and Neuroprotective Features of Aryl-Substituted Analogs of Gamma-Aminobutyric Acid.

PubMed

Tyurenkov, I N; Borodkina, L E; Bagmetova, V V; Berestovitskaya, V M; Vasil'eva, O S

2016-02-01

GABA analogs containing phenyl (phenibut) or para-chlorophenyl (baclofen) substituents demonstrated nootropic activity in a dose of 20 mg/kg: they improved passive avoidance conditioning, decelerated its natural extinction, and exerted antiamnestic effect on the models of amnesia provoked by scopolamine or electroshock. Tolyl-containing GABA analog (tolibut, 20 mg/kg) exhibited antiamnestic activity only on the model of electroshock-induced amnesia. Baclofen and, to a lesser extent, tolibut alleviated seizures provoked by electroshock, i.e. both agents exerted anticonvulsant effect. All examined GABA aryl derivatives demonstrated neuroprotective properties on the maximum electroshock model: they shortened the duration of coma and shortened the period of spontaneous motor activity recovery. In addition, these agents decreased the severity of passive avoidance amnesia and behavioral deficit in the open field test in rats exposed to electroshock. The greatest neuroprotective properties were exhibited by phenyl-containing GABA analog phenibut.

[Effect of diisobutyl phthalate on learning and memory behavior and apoptosis of hippocampus cells in mice].

PubMed

Ma, Ning; Liu, Shan; Gao, Peng; Cao, Pei; Xu, Haibin

2013-01-01

To give the original research of diisobutyl phthalate (DiBP) on learning and memory behavior, determine whether it can through blood-brain barrier and effect apoptosis of hippocampus cells in mice. Accommodating 60 Kunming mice to the animal house for 3 days, then dividing the mice into 5 groups according to their weights. That is, one control group and four experimental groups (I group, 50 mg/kg BW. II group, 250mg/kg BW. III group, 500 mg/kg BW. IV group, 1000 mg/kg BW). The mice were fed with the corn oil in control group, and the other groups were fed with the related dose of diisobutyl phthalate mixture by gavages last for 8 weeks. At the end of experimental time, passive avoidance response was examined, then all of mice were killed, and choosed the brain tissues to test the DiBP content and apoptosis rate of hippocampal cells and hippocampal ultrastructural alterations on electron microscopy. In the passive avoidance response test, the exposed animals of IV group showed learning impairment as compared to unexposed mice (P < 0.05). DiBP was detected in III group and IV group, the mean content of them were (1.27 +/- 0.56) and (1.96 +/- 0.42) microg/g. The apoptosis rate of hippocampal cells (IV group vs control group) increase significantly (P < 0.05). Hippocampal ultrastructural were damaged in all dose-groups. As a result, in the experiments, exposure to DiBP could exert passive avoidance neurobehavioral effects. DiBP could through blood-brain barrier after oral intake, and disordered the way of apoptosis of hippocampal cells, and morphologic change of mitochondria mybe is the main reason of changes of neuron apoptosis.

Acupuncture inhibits the decrease in brain catecholamine contents and the impairment of passive avoidance task in ovariectomized mice.

PubMed

Toriizuka, K; Okumura, M; Iijima, K; Haruyama, K; Cyong, J C

1999-01-01

The effects of acupuncture on the disorders elicited by abnormalities of endocrine system were investigated in ovariectomized mice. Female mice (strain; C57BL/6) were ovariectomized (OVX) and acupuncture points, Shenshu ([Japanese pictograph see text] : BL23) on both side of the back were continuously stimulated by subcutaneous needles for 20 days. After completion of experimental sessions, animals were sacrificed and specific brain regions were assayed for catecholamine contents by high performance liquid chromatography with electro chemical detector (ECD-HPLC). The mitogenic activities of splenic lymphocytes were measured by using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTS) assay and alkaline phosphatase (ALP) assay. Furthermore, the effects of needle stimulation on learning and memory ability were studied by the step-through type passive avoidance test. Norepinephrine and dopamine contents in the frontoparietal cerebral cortex, ventral hippocampus and olfactory bulb were decreased in the OVX group, and both MTS activity and ALP activity were decreased 20 days after ovariectomy. The mean latent period was also shortened in the passive avoidance test in the OVX group. However, applying needle stimulation increased norepinephrine and dopamine contents in the brain regions, and enhanced mitogenic activities of splenic lymphocytes. The stimulation also improved memory-related behavior. It was concluded from this study that after mice were stimulated by subcutaneous needle insertion, overall changes were observed in central nervous system (including retention of memory) and immune functions. The study suggests that acupuncture improves the memory loss and decrease of immune responses accompanying aging and/or menopause, and the that it may have an important role in medical care for the elderly.

Learning and memory effects of neonatal methamphetamine exposure in rats: Role of reactive oxygen species and age at assessment.

PubMed

Jablonski, Sarah A; Williams, Michael T; Vorhees, Charles V

2017-11-01

In utero methamphetamine (MA) exposure leads to a range of adverse effects, such as decreased attention, reduced working-memory capability, behavioral dysregulation, and spatial memory impairments in exposed children. In the current experiment, preweaning Sprague-Dawley rats-as a model of third trimester human exposure-were administered the spin trapping agent, N-tert-butyl-α-phenylnitrone (PBN), daily prior to MA. Rats were given 0 (SAL) or 40 mg/kg PBN prior to each MA dose (10 mg/kg, 4× per day) from postnatal day (P) 6-15. Littermates underwent Cincinnati water maze, Morris water maze, and radial water maze assessment beginning on P30 (males) or P60 (females). Males were also tested for conditioned contextual and cued freezing, while females were trained in passive avoidance. Findings show that, regardless of age/sex, neonatal MA induced deficits in all tests, except passive avoidance. PBN did not ameliorate these effects, but had a few minor effects. Taken together, MA induced learning deficits emerge early and persist, but the mechanism remains unknown. © 2017 Wiley Periodicals, Inc.

A Novel Approach to the Design of Passive Filters in Electric Grids

NASA Astrophysics Data System (ADS)

Filho da Costa Castro, José; Lima, Lucas Ramalho; Belchior, Fernando Nunes; Ribeiro, Paulo Fernando

2016-12-01

The design of shunt passive filters has been a topic of constant research since the 70's. Due to the lower cost, passive shunt filters are still considered a preferred option. This paper presents a novel approach for the placement and sizing of passive filters through ranking solutions based on the minimization of the total harmonic distortion (THDV) of the supply system rather than one specific bus, without neglecting the individual harmonic distortions. The developed method was implemented using Matlab/Simulink and applied to a test system. The results shown that is possible to minimize the total voltage harmonic distortion using a system approach during the filter selection. Additionally, since the method is mainly based on a heurist approach, it avoids the complexity associated with of use of advanced mathematical tools such as artificial intelligence techniques. The analyses contemplate a sinusoidal voltage utility and also the condition with background distortion utility.

Passive avoidance and complex maze learning in the senescence accelerated mouse (SAM): age and strain comparisons of SAM P8 and R1.

PubMed

Spangler, Edward L; Patel, Namisha; Speer, Dorey; Hyman, Michael; Hengemihle, John; Markowska, Alicja; Ingram, Donald K

2002-02-01

Two strains of the senescence accelerated mouse, P8 and R1,were tested in footshock-motivated passive avoidance (PA; P8, 3-21 months; R1, 3-24 months) and 14-unit T-maze (P8 and R1, 9, and 15 months) tasks. For PA, entry to a dark chamber from a lighted chamber was followed by a brief shock. Latency to enter the dark chamber 24 hours later served as a measure of retention. Two days of active avoidance training in a straight runway preceded 2 days (8 trials/day) of testing in the 14-unit T-maze. For PA retention, older P8 mice entered the dark chamber more quickly than older R1 mice, whereas no differences were observed between young P8 or R1 mice. In the 14-unit T-maze, age-related learning performance deficits were reflected in higher error scores for older mice. P8 mice were actually superior learners; that is, they had lower error scores compared with those of age-matched R1 counterparts. Although PA learning results were in agreement with other reports, results obtained in the 14-unit T-maze were not consistent with previous reports of learning impairments in the P8 senescence accelerated mouse.

The hydroalcoholic extract of Salvia elegans induces anxiolytic- and antidepressant-like effects in rats.

PubMed

Mora, S; Millán, R; Lungenstrass, H; Díaz-Véliz, G; Morán, J A; Herrera-Ruiz, M; Tortoriello, J

2006-06-15

Behavioral effects of a hydroalcoholic (60% ethanol) extract from the leaves of Salvia elegans Vahl (Lamiaceae) were studied in male Sprague-Dawley rats. The extract was administered intraperitoneally and its effects on spontaneous motor activity (total motility, locomotion, rearing and grooming behavior) were monitored. Putative anxiolytic and antidepressant properties of Salvia elegans were studied in the elevated plus-maze test (EPM) and in the forced swimming test (FST), respectively. Deleterious effects of Salvia elegans on learning and memory were also studied by using active and passive avoidance paradigms. The results revealed that all doses (3.12, 12.5, 25 and 50 mg/kg) of the extract caused a significant decrease in total motility, locomotion, rearing and grooming behavior. Only the dose of 12.5 mg/kg increased the exploration of the EPM open arms in a similar way to that of diazepam (1 mg/kg). In the FST, all doses of the extract induced a reduction of immobility, in a similar way to that of fluoxetine (10 mg/kg) and imipramine (12.5 mg/kg), along with a significant increase in the time spent in swimming behavior. Acquisition of active avoidance responses was disrupted by pre-treatment with the extract, but retention of a passive avoidance response was not significantly modified. These results suggest that some of the components of the hydroalcoholic extract of Salvia elegans have psychotropic properties, which deserve further investigation.

Effect of pregabalin on fear-based conditioned avoidance learning and spatial learning in a mouse model of scopolamine-induced amnesia.

PubMed

Sałat, Kinga; Podkowa, Adrian; Malikowska, Natalia; Trajer, Jędrzej

2017-03-01

Cognitive deficits are one of the frequent symptoms accompanying epilepsy or its treatment. In this study, the effect on cognition of intraperitoneally administered antiepileptic drug, pregabalin (10 mg/kg), was investigated in scopolamine-induced memory-impaired mice in the passive avoidance task and Morris water maze task. The effect of scopolamine and pregabalin on animals' locomotor activity was also studied. In the retention phase of the passive avoidance task, pregabalin reversed memory deficits induced by scopolamine (p < 0.05). During the acquisition phase of the Morris water maze pregabalin-treated memory-impaired mice performed the test with longer escape latencies than the vehicle-treated mice (significant at p < 0.05 on Day 5, and at p < 0.001 on Day 6). There were no differences in this parameter between the scopolamine-treated control group and pregabalin-treated memory-impaired mice, which indicated that pregabalin had no influence on spatial learning in this task. During the probe trial a significant difference (p < 0.05) was observed in terms of the mean number of target crossings between vehicle-treated mice and pregabalin-treated memory-impaired mice but there was no difference between the scopolamine-treated control group and mice treated with pregabalin + scopolamine. Pregabalin did not influence locomotor activity increased by scopolamine. In passive avoidance task, pregabalin reversed learning deficits induced by scopolamine. In the Morris water maze, pregabalin did not influence spatial learning deficits induced by scopolamine. These results are relevant for epileptic patients treated with pregabalin and those who use it for other therapeutic indications (anxiety, pain).

Detrimental Effects of Helium Ion Irradiation on Cognitive Performance and Cortical Levels of MAP-2 in B6D2F1 Mice.

PubMed

Raber, Jacob; Torres, Eileen Ruth S; Akinyeke, Tunde; Lee, Joanne; Weber Boutros, Sydney J; Turker, Mitchell S; Kronenberg, Amy

2018-04-20

The space radiation environment includes helium (⁴He) ions that may impact brain function. As little is known about the effects of exposures to ⁴He ions on the brain, we assessed the behavioral and cognitive performance of C57BL/6J × DBA2/J F1 (B6D2F1) mice three months following irradiation with ⁴He ions (250 MeV/n; linear energy transfer (LET) = 1.6 keV/μm; 0, 21, 42 or 168 cGy). Sham-irradiated mice and mice irradiated with 21 or 168 cGy showed novel object recognition, but mice irradiated with 42 cGy did not. In the passive avoidance test, mice received a slight foot shock in a dark compartment, and latency to re-enter that compartment was assessed 24 h later. Sham-irradiated mice and mice irradiated with 21 or 42 cGy showed a higher latency on Day 2 than Day 1, but the latency to enter the dark compartment in mice irradiated with 168 cGy was comparable on both days. ⁴He ion irradiation, at 42 and 168 cGy, reduced the levels of the dendritic marker microtubule-associated protein-2 (MAP-2) in the cortex. There was an effect of radiation on apolipoprotein E (apoE) levels in the hippocampus and cortex, with higher apoE levels in mice irradiated at 42 cGy than 168 cGy and a trend towards higher apoE levels in mice irradiated at 21 than 168 cGy. In addition, in the hippocampus, there was a trend towards a negative correlation between MAP-2 and apoE levels. While reduced levels of MAP-2 in the cortex might have contributed to the altered performance in the passive avoidance test, it does not seem sufficient to do so. The higher hippocampal and cortical apoE levels in mice irradiated at 42 than 168 cGy might have served as a compensatory protective response preserving their passive avoidance memory. Thus, there were no alterations in behavioral performance in the open filed or depressive-like behavior in the forced swim test, while cognitive impairments were seen in the object recognition and passive avoidance tests, but not in the contextual or cued fear conditioning tests. Taken together, the results indicate that some aspects of cognitive performance are altered in male mice exposed to ⁴He ions, but that the response is task-dependent. Furthermore, the sensitive doses can vary within each task in a non-linear fashion. This highlights the importance of assessing the cognitive and behavioral effects of charged particle exposure with a variety of assays and at multiple doses, given the possibility that lower doses may be more damaging due to the absence of induced compensatory mechanisms at higher doses.

Professor Age and Research Assistant Ratings of Passive-Avoidant and Proactive Leadership: The Role of Age-Related Work Concerns and Age Stereotypes

ERIC Educational Resources Information Center

Zacher, Hannes; Bal, P. Matthijs

2012-01-01

Recent research has shown that, in general, older professors are rated to have more passive-avoidant leadership styles than younger professors by their research assistants. The current study investigated professors' age-related work concerns and research assistants' favorable age stereotypes as possible explanations for this finding. Data came…

Intrahippocampal Insulin Improves Memory in a Passive-Avoidance Task in Male Wistar Rats

ERIC Educational Resources Information Center

Babri, Shirin; Badie, Hamid Gholamipour; Khamenei, Saeed; Seyedlar, Mehdi Ordikhani

2007-01-01

The main impacts of insulin favor the peripheral organs. Although it functions as a neuropeptide, insulin possesses also some central effects. The aim of this study was to determine the effect of intrahippocampal infusion of insulin on passive avoidance learning in healthy male rats. Thirty male wistar rats were divided into three groups (n = 10…

Acute Effects of Ecstasy on Memory Are more Extensive than Chronic Effects

PubMed Central

Shariati, Mohamad Bakhtiar Hesam; Sohrabi, Maryam; Shahidi, Siamak; Nikkhah, Ali; Mirzaei, Fatemeh; Medizadeh, Mehdi; Asl, Sara Soleimani

2014-01-01

Introduction Exposure to 3, 4- methylenedioxymethamphetamine (MDMA) could lead to serotonergic system toxicity in the brain. This system is responsible for learning and memory functions. Studies show that MDMA causes memory impairment dose-dependently and acutely. The present study was designed to evaluate the chronic and acute effects of MDMD on spatial memory and acquisition of passive avoidance. Methods Adult male Wistar rats (200-250 g) were given single or multiple injections of MDMA (10 mg/kg, IP). Using passive avoidance and Morris Water Maze (MWM) tasks, learning and spatial memory functions were assessed. The data were analyzed by SPSS 16 software and one- way analysis of variance (ANOVA) test. Results Our results showed that there were significant differences in latency to enter the dark compartment (STL) between sham and MDMA- treated groups. Acute group significantly showed more STL in comparison with chronic group. Furthermore, MDMA groups spent more time in dark compartment (TDS) than the sham group. Administration of single dose of MDMA significantly caused an increase in TDS compared with the chronic group. In the MWM, MDMA treatment significantly increased the traveled distance and escaped latency compared to the sham group. Like to passive avoidance task, percentage of time spent in the target quadrant in MDMA- treated animals impaired in MWM compared with sham group. Discussion These data suggest that MDMA treatment impairs learning and memory functions that are more extensive in acute- treated rats. PMID:25337384

The effect of chronic stimulation of serotonin receptor type 7 on recognition, passive avoidance memory, hippocampal long-term potentiation, and neuronal apoptosis in the amyloid β protein treated rat.

PubMed

Shahidi, Siamak; Asl, Sara Soleimani; Komaki, Alireza; Hashemi-Firouzi, Nasrin

2018-05-01

Alzheimer's disease (AD) is a neurodegenerative disorder characterized by memory impairment, neuronal death, and synaptic loss in the hippocampus. Long-term potentiation (LTP), a type of synaptic plasticity, occurs during learning and memory. Serotonin receptor type 7 (5-HTR7) activation is suggested as a possible therapeutic target for AD. The aim of the present study was to examine the effects of chronic treatment with the 5-HTR7 agonist, AS19, on cognitive function, memory, hippocampal plasticity, amyloid beta (Aβ) plaque accumulation, and apoptosis in an adult rat model of AD. AD was induced in rats using Aβ (single 1 μg/μL intracerebroventricular (icv) injection during surgery). The following experimental groups were included: control, sham-operated, Aβ + saline (1 μL icv for 30 days), and Aβ + AS19 (1 μg/μL icv for 30 days) groups. The animals were tested for cognition and memory performance using the novel object recognition and passive avoidance tests, respectively. Next, anesthetized rats were placed in a stereotaxic apparatus for electrode implantation, and field potentials were recorded in the hippocampal dentate gyrus. Lastly, brains were removed and Aβ plaques and neuronal apoptosis were evaluated using Congo red staining and TUNEL assay, respectively. Administration of AS19 in the Aβ rats increased the discrimination index of the novel object recognition test. Furthermore, AS19 treatment decreased time spent in the dark compartment during the passive avoidance test. AS19 also enhanced both the population spike (PS) amplitude and the field excitatory postsynaptic potential (fEPSP) slope evoked potentials of the LTP components. Aβ plaques and neuronal apoptosis were decreased in the AS19-treated Aβ rats. These results indicate that chronic treatment with a 5-HTR7 agonist can prevent Aβ-related impairments in cognition and memory performance by alleviating Aβ plaque accumulation and neuronal apoptosis, hence improving neuronal plasticity. AS19 may be useful as a therapeutic agent for AD.

Ontogeny of passive avoidance learning in domestic chicks: punishment of key-peck and running responses.

PubMed

Mattingly, B A; Zolman, J F

1980-08-01

The effect of the number of prepunishment acquisition trials on the age dependency of passive avoidance (PA) learning of the Vantress X Arbor Acre chick was determined in both key-peck and runway tests. In nine experiments, 1- and 4-day-old chicks were first trained to respond for heat reward, and then, following a variable number of reinforced acquisition trials, the chicks' responses were punished with aversive wing shocks. The major finding of these experiments was that the age dependency of PA learning of the young chick is related specifically to the number of reinforced training trials given prior to PA testing. When a large number of prepunishment acquisition trials were given, 1-day-old chicks learned as quickly as 4-day-old chicks to withhold responding when punished. However, when only a few acquisition trials preceded PA testing, 1-day-old chicks showed significantly less response suppression than 4-day-old chicks. These acquisition effects indicate that the age-dependent changes in PA learning of the chick are not solely due to developmental changes in general inhibitory ability. Rather, these PA results suggest that the 1-day-old chick, compared with the 4-day-old chick, is deficient in learning, or detecting changes in, stimulus- and/or response-reinforcement contingencies.

Submarine Combat Systems Engineering Project Capstone Project

DTIC Science & Technology

2011-06-06

sonar , imaging, Electronic Surveillance (ES) and communications. These sensors passively detect contacts, which emit... passive sensors is included. A Search Detect Identify Track Decide Engage Assess 3 contact can be sensed by the system as either surface or... Detect Track Avoid Search Detect Identify Track Search Engage Assess Detect Track Avoid Search • SONAR •Imagery •TC • SONAR • SONAR •EW •Imagery •ESM

Developmental subchronic exposure to diphenylarsinic acid induced increased exploratory behavior, impaired learning behavior, and decreased cerebellar glutathione concentration in rats.

PubMed

Negishi, Takayuki; Matsunaga, Yuki; Kobayashi, Yayoi; Hirano, Seishiro; Tashiro, Tomoko

2013-12-01

In Japan, people using water from the well contaminated with high-level arsenic developed neurological, mostly cerebellar, symptoms, where diphenylarsinic acid (DPAA) was a major compound. Here, we investigated the adverse effects of developmental exposure to 20mg/l DPAA in drinking water (early period [0-6 weeks of age] and/or late period [7-12]) on behavior and cerebellar development in male rats. In the open field test at 6 weeks of age, early exposure to DPAA significantly increased exploratory behaviors. At 12 weeks of age, late exposure to DPAA similarly increased exploratory behavior independent of the early exposure although a 6-week recovery from DPAA could reverse that change. In the passive avoidance test at 6 weeks of age, early exposure to DPAA significantly decreased the avoidance performance. Even at 12 weeks of age, early exposure to DPAA significantly decreased the test performance, which was independent of the late exposure to DPAA. These results suggest that the DPAA-induced increase in exploratory behavior is transient, whereas the DPAA-induced impairment of passive avoidance is long lasting. At 6 weeks of age, early exposure to DPAA significantly reduced the concentration of cerebellar total glutathione. At 12 weeks of age, late, but not early, exposure to DPAA also significantly reduced the concentration of cerebellar glutathione, which might be a primary cause of oxidative stress. Early exposure to DPAA induced late-onset suppressed expression of NMDAR1 and PSD95 protein at 12 weeks of age, indicating impaired glutamatergic system in the cerebellum of rats developmentally exposed to DPAA.

Design, synthesis and nootropic activity of new analogues of sunifiram and sapunifiram, two potent cognition-enhancers.

PubMed

Martini, Elisabetta; Salvicchi, Alberto; Ghelardini, Carla; Manetti, Dina; Dei, Silvia; Guandalini, Luca; Martelli, Cecilia; Melchiorre, Michele; Cellai, Cristina; Scapecchi, Serena; Teodori, Elisabetta; Romanelli, Maria Novella

2009-11-01

A series of amides and sulfonamides, structurally related to DM235 (sunifiram) and MN19 (sapunifiram), derived by ring expansion or contraction, or by inversion of the exocyclic amide function, have been synthesized and tested for cognition-enhancing activity in the mouse passive-avoidance test. Some of the compounds display good antiamnesic and procognitive activity, with higher potency than piracetam, and with a potency similar to the parent compounds.

Pervasive hyperactivity and long-term learning impairments in rats with induced micrencephaly from prenatal exposure to methylazoxymethanol.

PubMed

Vorhees, C V; Fernandez, K; Dumas, R M; Haddad, R K

1984-07-01

Pregnant Long-Evans rats were given a single i.p. injection of 30 mg/kg of methylazoxymethanol (MAM) acetate or saline on day 14 of gestation (vaginal plug = day 0). All litters were reduced to 8 at birth and were reared by their biological dams. Between 49-192 days of age all offspring were examined on open-field, figure-8 (at two different ages), and hole-board tests of activity, as well as passive avoidance and Biel water maze tests of learning (also at two different ages). The MAM offspring showed no increase in mortality, but weighed less than controls, a difference that remained relatively constant throughout the experiment. At 204-215 days of age the MAM offspring were confirmed to be micrencephalic, a known effect of this drug at this dose and exposure period. On all tests of activity the MAM offspring were markedly hyperactive. The female progeny also exhibited a pronounced impairment of normal activity habituation patterns. The MAM males, however, showed a marked impairment of passive avoidance performance, while the females did not. At 2 months of age the MAM offspring also showed a pronounced deficit in learning a water maze. This maze deficit had not abated when tested again at 6 months of age. The MAM induced brain and behavioral abnormalities provide a potentially useful animal model of congenital micrencephaly and associated mental retardation.

Neurotoxicity of neem commercial formulation (Azadirachta indica A. Juss) in adult zebrafish (Danio rerio).

PubMed

Bernardi, M M; Dias, S G; Barbosa, V E

2013-11-01

The neurotoxic effects of a commercial formulation of Azadirachta indica A. Juss, also called neem or nim, in adult zebrafish were determined using behavioral models. General activity, anxiety-like effects, and learning and memory in a passive avoidance task were assessed after exposure to 20 or 40 μl/L neem. The results showed that 20 μl/L neem reduced the number of runs. Both neem concentrations increased the number of climbs to the water surface, and 40 μl/L increased the number of tremors. In the anxiety test, the 20 μl/L dose increased the number of entries in the light side compared with controls, but the latency to enter the dark side and the freezing behavior in this side did not changed. In relation to controls, the 40 μl/L neem reduced the latency to enter in the light side, did not change the number of entries in this side and increased freezing behavior in the light side. In the passive avoidance test, pre-training and pre-test neem exposure to 40 μl/L decreased the response to the learning task. Thus, no impairment was observed in this behavioral test. We conclude that neem reduced general activity and increased anxiety-like behavior but did not affect learning and memory. Copyright © 2013 Elsevier B.V. All rights reserved.

Cognitive-enhancing effects of hydrolysate of polygalasaponin in SAMP8 mice*

PubMed Central

Xu, Pan; Xu, Shu-ping; Wang, Ke-zhu; Lu, Cong; Zhang, Hong-xia; Pan, Rui-le; Qi, Chang; Yang, Yan-yan; Li, Ying-hui; Liu, Xin-min

2016-01-01

Objectives: The aim of the study is to evaluate the cognitive-enhancing effects of hydrolysate of polygalasaponin (HPS) on senescence accelerate mouse P8 (SAMP8) mice, an effective Alzheimer’s disease (AD) model, and to research the relevant mechanisms. Methods: The cognitive-enhancing effects of HPS on SAMP8 mice were assessed using Morris water maze (MWM) and step-through passive avoidance tests. Then N-methyl-D-aspartate (NMDA) receptor subunit expression for both the cortex and hippocampus of mice was observed using Western blotting. Results: HPS (25 and 50 mg/kg) improved the escape rate and decreased the escape latency and time spent in the target quadrant for the SAMP8 mice in the MWM after oral administration of HPS for 10 d. Moreover, it decreased error times in the passive avoidance tests. Western blotting showed that HPS was able to reverse the levels of NMDAR1 and NMDAR2B expression in the cortex or hippocampus of model mice. Conclusions: The present study suggested that HPS can improve cognitive deficits in SAMP8 mice, and this mechanism might be associated with NMDA receptor (NMDAR)-related pathways. PMID:27381727

Cognitive benefits of Angiotensin IV and Angiotensin-(1-7): a systematic review of experimental studies.

PubMed

Ho, Jean K; Nation, Daniel A

2018-05-04

To explore effects of the brain renin-angiotensin system (RAS) on cognition. Systematic review of experimental (non-human) studies assessing cognitive effects of RAS peptides angiotensin-(3-8) [Ang IV] and angiotensin-(1-7) [Ang-(1-7)] and their receptors, the Ang IV receptor (AT4R) and the Mas receptor. Of 450 articles identified, 32 met inclusion criteria. Seven of 11 studies of normal animals found Ang IV had beneficial effects on tests of passive or conditioned avoidance and object recognition. In models of cognitive deficit, eight of nine studies found Ang IV and its analogs (Nle 1 -Ang IV, dihexa, LVV-hemorphin-7) improved performance on spatial working memory and passive avoidance tasks. Two of three studies examining Ang-(1-7) found it benefited memory. Mas receptor removal was associated with reduced fear memory in one study. Studies of cognitive impairment show salutary effects of acute administration of Ang IV and its analogs, as well as AT4R activation. Brain RAS peptides appear most effective administered intracerebroventricularly, close to the time of learning acquisition or retention testing. Ang-(1-7) shows anti-dementia qualities. Copyright © 2018. Published by Elsevier Ltd.

Curcumin exerts neuroprotective effects against homocysteine intracerebroventricular injection-induced cognitive impairment and oxidative stress in rat brain.

PubMed

Ataie, Amin; Sabetkasaei, Masoumeh; Haghparast, Abbas; Moghaddam, Akbar Hajizadeh; Ataee, Ramin; Moghaddam, Shiva Nasiraei

2010-08-01

Aging is the major risk factor for neurodegenerative diseases and oxidative stress and is involved in their pathophysiology. Oxidative stress can induce neuronal damage and modulate intracellular signaling, ultimately leading to neuronal death by apoptosis or necrosis. In this study we investigated the neuroprotective properties of the natural polyphenolic antioxidant compound, curcumin, against homocysteine (Hcy) neurotoxicity. Curcumin (5, 15, or 45 mg/kg) was injected intraperitoneally once daily for a period of 10 days beginning 5 days prior to Hcy (0.2 micromol/microl) intracerebroventricular injection in rats. Biochemical and behavioral studies, including passive avoidance learning and locomotor activity tests, were evaluated 24 hours after the last injection of curcumin or vehicle. Results indicated that Hcy induces lipid peroxidation and increases malondialdehyde (MDA) and superoxide anion (SOA) levels in whole rat brain. In addition, Hcy impaired memory retention in the passive avoidance learning test. However, curcumin treatment significantly decreased MDA and SOA levels and improved learning and memory in rats. These results suggest that Hcy may induce lipid peroxidation in rat brain and that polyphenol treatment (curcumin) improves learning and memory deficits by protecting the nervous system against oxidative stress.

Prevalence of personality disorders in patients with chronic migraine.

PubMed

Kayhan, Fatih; Ilik, Faik

2016-07-01

The present study aimed to investigate the prevalence of personality disorders (PDs) in patients with chronic migraine (CM). This study included 105 CM patients who were diagnosed according to the criteria of the International Headache Society (IHS) and 100 healthy volunteers. PDs were diagnosed with the Structured Clinical Interview for DSM, Revised Third Edition Personality Disorders, and pain severity and level of disability were assessed with the Migraine Disability Assessment (MIDAS) test. Of the 105 CM patients, 85 (81%) had at least one PD. PDs were more prevalent in the patient group than in the healthy control group, and the most common PDs were obsessive-compulsive (n=53, 50.5%), dependent (n=20, 19%), avoidant (n=20, 19%), and passive-aggressive (n=14, 13.3%) PDs. The MIDAS scores of the CM patients with PDs were higher than those of the CM patients without PDs. PDs, particularly obsessive-compulsive, dependent, avoidant, and passive-aggressive PDs, were frequently observed in CM patients in the present study. Copyright © 2016 Elsevier Inc. All rights reserved.

Effects of environmental enrichment on behavioral deficits and alterations in hippocampal BDNF induced by prenatal exposure to morphine in juvenile rats.

PubMed

Ahmadalipour, A; Sadeghzadeh, J; Vafaei, A A; Bandegi, A R; Mohammadkhani, R; Rashidy-Pour, A

2015-10-01

Prenatal morphine exposure throughout pregnancy can induce a series of neurobehavioral and neurochemical disturbances by affecting central nervous system development. This study was designed to investigate the effects of an enriched environment on behavioral deficits and changes in hippocampal brain-derived neurotrophic factor (BDNF) levels induced by prenatal morphine in rats. On pregnancy days 11-18, female Wistar rats were randomly injected twice daily with saline or morphine. Offspring were weaned on postnatal day (PND) 21. They were subjected to a standard rearing environment or an enriched environment on PNDs 22-50. On PNDs 51-57, the behavioral responses including anxiety and depression-like behaviors, and passive avoidance memory as well as hippocampal BDNF levels were investigated. The light/dark (L/D) box and elevated plus maze (EPM) were used for the study of anxiety, forced swimming test (FST) was used to assess depression-like behavior and passive avoidance task was used to evaluate learning and memory. Prenatal morphine exposure caused a reduction in time spent in the EPM open arms and a reduction in time spent in the lit side of the L/D box. It also decreased step-through latency and increased time spent in the dark side of passive avoidance task. Prenatal morphine exposure also reduced immobility time and increased swimming time in FST. Postnatal rearing in an enriched environment counteracted with behavioral deficits in the EPM and passive avoidance task, but not in the L/D box. This suggests that exposure to an enriched environment during adolescence period alters anxiety profile in a task-specific manner. Prenatal morphine exposure reduced hippocampal BDNF levels, but enriched environment significantly increased BDNF levels in both saline- and morphine-exposed groups. Our results demonstrate that exposure to an enriched environment alleviates behavioral deficits induced by prenatal morphine exposure and up-regulates the decreased levels of BDNF. BDNF may contribute to the beneficial effects of an enriched environment on prenatal morphine-exposed to rats. Copyright © 2015 IBRO. Published by Elsevier Ltd. All rights reserved.

Determination of trichloroanisole and trichlorophenol in wineries' ambient air by passive sampling and thermal desorption-gas chromatography coupled to tandem mass spectrometry.

PubMed

Camino-Sánchez, F J; Bermúdez-Peinado, R; Zafra-Gómez, A; Ruíz-García, J; Vílchez-Quero, J L

2015-02-06

The present paper describes the calibration of selected passive samplers used in the quantitation of trichlorophenol and trichloroanisole in wineries' ambient air, by calculating the corresponding sampling rates. The method is based on passive sampling with sorbent tubes and involves thermal desorption-gas chromatography-triple quadrupole mass spectrometry analysis. Three commercially available sorbents were tested using sampling cartridges with a radial design instead of axial ones. The best results were found for Tenax TA™. Sampling rates (R-values) for the selected sorbents were determined. Passive sampling was also used for accurately determining the amount of compounds present in the air. Adequate correlation coefficients between the mass of the target analytes and exposure time were obtained. The proposed validated method is a useful tool for the early detection of trichloroanisole and its precursor trichlorophenol in wineries' ambient air while avoiding contamination of wine or winery facilities. Copyright © 2015 Elsevier B.V. All rights reserved.

Effects of neural progenitor cells on post-stroke neurological impairment—a detailed and comprehensive analysis of behavioral tests

PubMed Central

Doeppner, Thorsten R.; Kaltwasser, Britta; Bähr, Mathias; Hermann, Dirk M.

2014-01-01

Systemic transplantation of neural progenitor cells (NPCs) in rodents reduces functional impairment after cerebral ischemia. In light of upcoming stroke trials regarding safety and feasibility of NPC transplantation, experimental studies have to successfully analyze the extent of NPC-induced neurorestoration on the functional level. However, appropriate behavioral tests for analysis of post-stroke motor coordination deficits and cognitive impairment after NPC grafting are not fully established. We therefore exposed male C57BL6 mice to either 45 min (mild) or 90 min (severe) of cerebral ischemia, using the thread occlusion model followed by intravenous injection of PBS or NPCs 6 h post-stroke with an observation period of three months. Post-stroke motor coordination was assessed by means of the rota rod, tight rope, corner turn, inclined plane, grip strength, foot fault, adhesive removal, pole test and balance beam test, whereas cognitive impairment was analyzed using the water maze, the open field and the passive avoidance test. Significant motor coordination differences after both mild and severe cerebral ischemia in favor of NPC-treated mice were observed for each motor coordination test except for the inclined plane and the grip strength test, which only showed significant differences after severe cerebral ischemia. Cognitive impairment after mild cerebral ischemia was successfully assessed using the water maze test, the open field and the passive avoidance test. On the contrary, the water maze test was not suitable in the severe cerebral ischemia paradigm, as it too much depends on motor coordination capabilities of test mice. In terms of both reliability and cost-effectiveness considerations, we thus recommend the corner turn, foot fault, balance beam, and open field test, which do not depend on durations of cerebral ischemia. PMID:25374509

Memory effects of Aronia melanocarpa fruit juice in a passive avoidance test in rats.

PubMed

Valcheva-Kuzmanova, Stefka V; Eftimov, Miroslav Tz; Tashev, Roman E; Belcheva, Iren P; Belcheva, Stiliana P

2014-01-01

To study the effect of Aronia melanocarpa fruit juice on memory in male Wistar rats. The juice was administered orally for 7, 14, 21 and 30 days at doses of 2.5 ml/kg, 5 ml/kg and 10 ml/kg. Memory was assessed in the one-way passive avoidance task (step through) which consisted of one training session and two retention tests (3 hours and 24 hours after training). The variables measured were the latency time to step into the dark compartment of the apparatus and the learning criterion (remaining in the illuminated compartment for at least 180 sec). Oral administration of Aronia melanocarpa fruit juice for 7 and 14 days resulted in a dose-dependent tendency to increase the latency time and the learning criterion compared to saline-treated controls but the effect failed to reach statistical significance. After 21 days of treatment, the juice dose-dependently prolonged the latency time at the retention tests, the effect being significant at doses of 5 ml/kg and 10 ml/kg. Applied for 30 days, the juice in all the tested doses increased significantly the latency time at the retention tests and the dose of 10 ml/kg significantly increased the percentage of rats reaching the learning criterion. These findings suggest that Aronia melanocarpa fruit juice could improve memory in rats. The effect is probably due to the polyphenolic ingredients of the juice which have been shown to be involved in learning and memory processes.

The influence of leadership style on subordinates' attachment to the leader.

PubMed

Molero, Fernando; Moriano, Juan A; Shaver, Phillip R

2013-01-01

The aim of this research is to explore the extent to which employees establish attachment bonds with their leaders and the effects these bonds have on organizational outcomes. A sample of 225 participants reported on their supervisor's leadership style (transformational, transactional, or passive-avoidant), their attachment bonds to this supervisor (anxious or avoidant), and four organizational variables (subordinate's satisfaction, identification with the organization, extra effort, and perceived leadership effectiveness). Results, analyzed using a Partial Least Squares (PLS) approach, indicated that (a) transformational leadership was negatively associated with employees' insecure (anxious or avoidant) attachment to their leader; (b) passive/avoidant leadership was positively associated with subordinates' insecure attachment to their leader; (c) transactional leadership was positively associated with employee's anxious attachment but not with their avoidant attachment; (d) avoidant, but not anxious, attachment to the leader was negatively associated with employee satisfaction, perceived leader effectiveness, employee's extra effort, and organizational identification.

Effects of the estrous cycle and ovarian hormones on behavioral indices of anxiety in female rats.

PubMed

Mora, S; Dussaubat, N; Díaz-Véliz, G

1996-10-01

The influence of the estrous cycle and the effects of exogenous administration of estradiol and progesterone on level of anxiety were studied in intact and ovariectomized rats. Intact Sprague-Dawley female rats were classified according to the stages of estrous cycle. Another group of rats was ovariectomized bilaterally and, 14 days after surgery, they received estradiol benzoate (10 micrograms/kg, s.c.) and/or progesterone (25 mg/kg, s.c.) or corn oil (1 ml/kg). The behavioral tests began 3 h after estradiol or 6 h after progesterone and consisted of: (1) exploration of an elevated plus-maze; and (2) retention of a passive avoidance response. Open-arm exploration of the plus-maze varied according to light intensity and the stages of the estrous cycle. There was a slight increase in open-arm exploration by rats in metestrus, under high light intensity. Low light intensity increased the exploration of the open arms by rats in proestrus and estrus, compared to the other phases of the cycle. Retention of the passive avoidance response was inhibited during proestrus and estrus. Progesterone increased open-arm exploration of the plus-maze under high light conditions, whereas estradiol antagonized this effect. Retention of passive avoidance was inhibited after estradiol or progesterone injection. These results suggest that the behavioral indices of anxiety can vary across the estrous cycle, that low light intensities have anxiolytic-like effects, and that the sensitivity to this effect is higher during proestrus and estrus. This could be explained through modulatory effects of ovarian hormones upon behavioral indices of anxiety.

Age moderates the effect of acute dopamine depletion on passive avoidance learning.

PubMed

Kelm, Mary Katherine; Boettiger, Charlotte Ann

2015-04-01

Despite extensive links between reinforcement-based learning and dopamine (DA), studies to date have not found consistent effects of acute DA reduction on reinforcement learning in both men and women. Here, we tested the effects of reducing DA on reward- and punishment-based learning using the deterministic passive avoidance learning (PAL) task. We tested 16 (5 female) adults (ages 22-40) in a randomized, cross-over design to determine whether reducing global DA by administering an amino acid beverage deficient in the DA precursors, phenylalanine and tyrosine (P/T[-]), would affect PAL task performance. We found that P/T[-] beverage effects on PAL performance were modulated by age. Specifically, we found that P/T depletion significantly improved learning from punishment with increasing participant age. Participants committed 1.49 fewer passive avoidance errors per additional year of age (95% CI, -0.71 - -2.27, r=-0.74, p=0.001). Moreover, P/T depletion improved learning from punishment in adults (ages 26-40) while it impaired learning from punishment in emerging adults (ages 22-25). We observed similar, but non-significant trends in learning from reward. While there was no overall effect of P/T-depletion on reaction time (RT), there was a relationship between the effect of P/T depletion on PAL performance and RT; those who responded more slowly on the P/T[-] beverage also made more errors on the P/T[-] beverage. When P/T-depletion slowed RT after a correct response, there was a worsening of PAL task performance; there was no similar relationship for the RT after an incorrect response and PAL task performance. Moreover, among emerging adults, changes in mood on the P/T[-] beverage negatively correlated with learning from reward on the P/T[-] beverage. Together, we found that both reward- and punishment-based learning are sensitive to central catecholamine levels, and that these effects of acute DA reduction vary with age. Copyright © 2015 Elsevier Inc. All rights reserved.

Effects of novel tacrine-related cholinesterase inhibitors in the reversal of 3-quinuclidinyl benzilate-induced cognitive deficit in rats--Is there a potential for Alzheimer's disease treatment?

PubMed

Misik, Jan; Korabecny, Jan; Nepovimova, Eugenie; Kracmarova, Alzbeta; Kassa, Jiri

2016-01-26

Inhibitors of cholinesterase are important drugs for therapy of Alzheimer's disease and the search for new modifications is extensive, including dual inhibitors or multi-target hybrid compounds. The aim of the present study was a preliminary evaluation of pro-cognitive effects of newly-developed 7-MEOTA-donepezil like hybrids (compounds no. 1 and 2) and N-alkylated tacrine derivatives (compounds no. 3 and 4) using an animal model of pharmacologically-induced cognitive deficit. Male Wistar rats were subjected to tests of learning and memory in a water maze and step-through passive avoidance task. Cognitive impairment was induced by 3-quinuclidinyl benzilate (QNB, 2mgkg(-1)), administered intraperitoneally 1h before training sessions. Cholinesterase inhibitors were administered as a single therapeutic dose following the QNB at 30min at the following dose rates; 1 (25.6mgkg(-1)), 2 (12.3mgkg(-1)), 3 (5.7mgkg(-1)), 4 (5.2mgkg(-1)). The decrease in total path within the 10-swim session (water maze), the preference for target quadrant (water maze) and the entrance latency (passive avoidance) were taken as indicators of learning ability in rats. The effects of novel compounds were compared to that of standards tacrine (5.2mgkg(-1)) and donepezil (2.65mgkg(-1)). QNB significantly impaired spatial navigation as well as fear learning. Generally, the performance of rats was improved when treated with novel inhibitors and this effect reached efficiency of standard donepezil at selected doses. There was a significant improvement in the groups treated with compounds 2 and 3 in all behavioral tasks. The rest of the novel compounds succeed in the passive avoidance test. In summary, the potential of novel inhibitors (especially compounds 2 and 3) was proved and further detailed evaluation of these compounds as potential drugs for Alzheimer's disease treatment is proposed. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

[Stimulation of D1-receptors improves passive avoidance learning of female rats during ovary cycle].

PubMed

Fedotova, Iu O; Sapronov, N S

2012-01-01

The involvement of D1-receptors in learning/memory processes during ovary cycle was assessed in the adult female rats. SKF-38393 (0,1 mg/kg, i.p.), D1-receptor agonist and SCH-23390 (0,1 mg/kg, i.p.), D1-receptor antagonist were injected chronically to adult female rats. Learning of these animals was assessed in different models: passive avoidance performance and Morris water maze. Chronic SKF-3839 administration to females resulted in the appearance of the passive avoidance performance in proestrous and estrous, as distinct from the control animals, but failed to change the dynamics of spatial learning in Morris water maze. Chronic SCH-23390 administration similarly impaired non-spatial and spatial learning in females during all phases of ovary cycle. The results of the study suggest modulating role of D1-receptors in learning/memory processes during ovary cycle in the adult female rats.

[Stimulation of D2-receptors improves passive avoidance learning in female rats].

PubMed

Fedotova, Iu O

2012-01-01

The involvement of D2-receptors in learning/memory processes during ovary cycle was assessed in the adult female rats. Quinperole (0,1 mg/kg, i.p.), D2-receptor agonist and sulpiride (10,0 mg/kg, i.p.), D2-receptor antagonist were injected chronically to adult female rats. Learning of these animals was assessed in different models: passive avoidance performance and Morris water maze. Chronic quinperole administration to females resulted in the appearance of the passive avoidance performance in proestrous and estrous, as distinct from the control animals. Also, quinperole improved spatial learning in proestrous and stimulated it in estrous in Morris water maze. Chronic sulpiride administration similarly impaired non-spatial and spatial learning in females during all phases of ovary cycle. The results of the study suggest modulating role of D2-receptors in learning/memory processes during ovary cycle in the adult female rats.

Effects of activation and blockade of NMDA receptors on the extinction of a conditioned passive avoidance response in mice with different levels of anxiety.

PubMed

Tomilenko, R A; Dubrovina, N I

2007-06-01

The effects of an agonist (D-cycloserine) and an antagonist (dizocilpine) of N-methyl-D-aspartate (NMDA) receptors on the learning and extinction of a conditioned passive avoidance response were studied in mice with low, intermediate, and high levels of anxiety. In intermediate-anxiety mice, D-cycloserine (30 mg/kg) had no effect on learning but accelerated extinction, while dizocilpine (0.15 mg/kg) degraded acquisition of the reflex but delayed extinction. In high-anxiety mice, with good learning and no extinction, D-cycloserine had no effect, while dizocilpine decreased learning and facilitated retention of performance of the memory trace at the ongoing level in conditions promoting extinction. In low-anxiety mice, D-cycloserine degraded learning and accelerated extinction, while dizocilpine completely blocked learning and the retention of the passive avoidance response.

Effects of prior aversive experience upon retrograde amnesia induced by hypothermia.

PubMed

Jensen, R A; Riccio, D C; Gehres, L

1975-08-01

Two experiments examined the extent to which retrograde amnesia (RA) is attenuated by prior learning experiences. In Experiment 1, rats initially received either passive avoidance training in a step-through apparatus, exposure to the apparatus, or noncontingent footshock. When training on a second but different passive avoidance task was followed by hypothermia treatment, RA was obtained only in the latter two groups. In Experiment 2, one-way active avoidance training, yoked noncontingent shocks, or apparatus exposure constituted the initial experience. Subsequent step-down passive avoidance training and amnestic treatment resulted in memory loss for the prior apparatus exposure group, but not for either of the preshocked conditions. These experiments demonstrate that certain types of prior aversive experience can substantially modify the magnitude of RA, and, in conjunction with other familiarization studies, emphasize a paradox for interpretations of RA based solely upon CNS disruption. The possibility that hypothermia treatment serves as an important contextual or encoding cue necessary for memory retrieval was considered. It was suggested that prior experience may block RA by enabling rats to differentiate training and treatment conditions.

Repeated administration of fresh garlic increases memory retention in rats.

PubMed

Haider, Saida; Naz, Nosheen; Khaliq, Saima; Perveen, Tahira; Haleem, Darakhshan J

2008-12-01

Garlic (Allium sativum) is regarded as both a food and a medicinal herb. Increasing attention has focused on the biological functions and health benefits of garlic as a potentially major dietary component. Chronic garlic administration has been shown to enhance memory function. Evidence also shows that garlic administration in rats affects brain serotonin (5-hydroxytryptamine [5-HT]) levels. 5-HT, a neurotransmitter involved in a number of physiological functions, is also known to enhance cognitive performance. The present study was designed to investigate the probable neurochemical mechanism responsible for the enhancement of memory following garlic administration. Sixteen adult locally bred male albino Wistar rats were divided into control (n = 8) and test (n = 8) groups. The test group was orally administered 250 mg/kg fresh garlic homogenate (FGH), while control animals received an equal amount of water daily for 21 days. Estimation of plasma free and total tryptophan (TRP) and whole brain TRP, 5-HT, and 5-hydroxyindole acetic acid (5-HIAA) was determined by high-performance liquid chromatography with electrochemical detection. For assessment of memory, a step-through passive avoidance paradigm (electric shock avoidance) was used. The results showed that the levels of plasma free TRP significantly increased (P < .01) and plasma total TRP significantly decreased (P < .01) in garlic-treated rats. Brain TRP, 5-HT, and 5-HIAA levels were also significantly increased following garlic administration. A significant improvement in memory function was exhibited by garlic-treated rats in the passive avoidance test. Increased brain 5-HT levels were associated with improved cognitive performance. The present results, therefore, demonstrate that the memory-enhancing effect of garlic may be associated with increased brain 5-HT metabolism in rats. The results further support the use of garlic as a food supplement for the enhancement of memory.

Developmental Subchronic Exposure to Diphenylarsinic Acid Induced Increased Exploratory Behavior, Impaired Learning Behavior, and Decreased Cerebellar Glutathione Concentration in Rats

PubMed Central

Negishi, Takayuki; Matsunaga, Yuki

2013-01-01

In Japan, people using water from the well contaminated with high-level arsenic developed neurological, mostly cerebellar, symptoms, where diphenylarsinic acid (DPAA) was a major compound. Here, we investigated the adverse effects of developmental exposure to 20mg/l DPAA in drinking water (early period [0–6 weeks of age] and/or late period [7–12]) on behavior and cerebellar development in male rats. In the open field test at 6 weeks of age, early exposure to DPAA significantly increased exploratory behaviors. At 12 weeks of age, late exposure to DPAA similarly increased exploratory behavior independent of the early exposure although a 6-week recovery from DPAA could reverse that change. In the passive avoidance test at 6 weeks of age, early exposure to DPAA significantly decreased the avoidance performance. Even at 12 weeks of age, early exposure to DPAA significantly decreased the test performance, which was independent of the late exposure to DPAA. These results suggest that the DPAA-induced increase in exploratory behavior is transient, whereas the DPAA-induced impairment of passive avoidance is long lasting. At 6 weeks of age, early exposure to DPAA significantly reduced the concentration of cerebellar total glutathione. At 12 weeks of age, late, but not early, exposure to DPAA also significantly reduced the concentration of cerebellar glutathione, which might be a primary cause of oxidative stress. Early exposure to DPAA induced late-onset suppressed expression of NMDAR1 and PSD95 protein at 12 weeks of age, indicating impaired glutamatergic system in the cerebellum of rats developmentally exposed to DPAA. PMID:24008832

Different Involvement of Type 1, 2, and 3 Ryanodine Receptors in Memory Processes

ERIC Educational Resources Information Center

Galeotti, Nicoletta; Quattrone, Alessandro; Vivoli, Elisa; Norcini, Monica; Bartolini, Alessandro; Ghelardini, Carla

2008-01-01

The administration of the ryanodine receptor (RyR) agonist 4-Cmc (0.003-9 nmol per mouse intracerebroventricularly [i.c.v.]) ameliorated memory functions, whereas the RyR antagonist ryanodine (0.0001-1 nmol per mouse i.c.v.) induced amnesia in the mouse passive avoidance test. The role of the type 1, 2, and 3 RyR isoforms in memory processes was…

Neuroprotective effects of the polyphenolic antioxidant agent, Curcumin, against homocysteine-induced cognitive impairment and oxidative stress in the rat.

PubMed

Ataie, Amin; Sabetkasaei, Masoumeh; Haghparast, Abbas; Moghaddam, Akbar Hajizadeh; Kazeminejad, Behrang

2010-10-01

Aging is the major risk factor for neurodegenerative diseases and oxidative stress is involved in the pathophysiology of these diseases. In this study, the possible antioxidant and neuroprotective properties of the polyphenolic antioxidant compound, Curcumin against homocysteine (Hcy) neurotoxicity was investigated. Curcumin (5 and 50mg/kg) was injected intraperitoneally once daily for a period of 10 days beginning 5 days prior to Hcy (0.2 micromol/microl) intrahippocampal injection in rats. Biochemical and behavioral studies, including passive avoidance learning and locomotor activity tests were studied 24h after the last Curcumin or its vehicle injection. We detected Malondialdehyde (MDA) and Super oxide anion (SOA) in rats' hippocampi. Results indicated that Hcy could induce lipid peroxidation and increase MDA and SOA levels in rats' hippocampi. Additionally, Hcy impaired memory retention in passive avoidance learning test. However, Curcumin treatment decreased MDA and SOA levels significantly as well as improved learning and memory in rats. Histopathological analysis also indicated that Hcy could decrease hippocampus cell count and Curcumin inhibited this toxic effect. These results suggest that Hcy may induce lipid peroxidation in rats' hippocampi and polyphenol treatment (Curcumin) improved learning and memory deficits by protecting the nervous system against Hcy toxicity. (c) 2010 Elsevier Inc. All rights reserved.

Synthesis and biological evaluation of 3,7-diazabicyclo[4.3.0]nonan-8-ones as potential nootropic and analgesic drugs.

PubMed

Martini, Elisabetta; Di Cesare Mannelli, Lorenzo; Bartolucci, Gianluca; Bertucci, Carlo; Dei, Silvia; Ghelardini, Carla; Guandalini, Luca; Manetti, Dina; Scapecchi, Serena; Teodori, Elisabetta; Romanelli, Maria Novella

2011-04-14

A series of cis and trans 3,7-diazabicyclo[4.3.0]nonan-8-ones has been synthesized and tested for their ability to revert scopolamine-induced amnesia in the mouse passive-avoidance test. The racemates of the most potent compounds 4 and 7 were separated and tested, but no enantioselectivity was found for the nootropic activity. Compounds 4 and 7 and their enantiomers displayed interesting antihyperalgesic activity in two models of neuropathic pain (streptozotocin-induced and oxalilplatin-induced neuropathy) in comparison with pregabalin.

Administration of midazolam in infancy does not affect learning and memory of adult mice.

PubMed

Xu, Hua; Liu, Zhi-Qiang; Liu, Yi; Zhang, Wei-Shi; Xu, Bo; Xiong, Yuan-Chang; Deng, Xiao-Ming

2009-12-01

1. Midazolam is a common fast-acting GABA(A) receptor agonist. Recent data suggest that exposure to midazolam in early life may cause long-term effects on brain function through stable epigenetic reprogramming. The aim of the present study was to determine whether the administration of midazolam to infant mice would affect their learning and memory in adulthood. 2. An open-field test was conducted before and then 3, 24, 48 and 72 h after administration of midazolam (50 mg/kg, i.p.) to infant mice. Saline control mice received an equal volume of saline i.p. 3 h before the open-field test. Total movements, total movement time, total movement distance and velocity were analysed. Novel object recognition (NOR), Morris water-maze and passive avoidance tests were performed when the treated mice grew to adulthood (105 days of age). 3. The results of open-field test showed that midazolam significantly reduced locomotor activity (total movements, total movement time, total movement distance and velocity) in infant mice 3 and 24 h after drug administration and that these effects had disappeared by 72 h after drug administration. The results of the water-maze, NOR and passive avoidance tests in adulthood (at 105 days of age) indicated that administration of midazolam in infancy had no long-term effects on the learning and memory behaviours of adult mice compared with the saline control. 4. Acute midazolam administration to infant mice affected spontaneous locomotor activity for approximately 2 days, but did not seem to have any significant impact on cognitive functioning that lasted into adulthood.

Emotional reactivity and cognitive performance in aversively motivated tasks: a comparison between four rat strains.

PubMed

van der Staay, F Josef; Schuurman, Teun; van Reenen, Cornelis G; Korte, S Mechiel

2009-12-15

Cognitive function might be affected by the subjects' emotional reactivity. We assessed whether behavior in different tests of emotional reactivity is correlated with performance in aversively motivated learning tasks, using four strains of rats generally considered to have a different emotional reactivity. The performance of male Brown Norway, Lewis, Fischer 344, and Wistar Kyoto rats in open field (OF), elevated plus-maze (EPM), and circular light-dark preference box (cLDB) tasks, which are believed to provide measures of emotional reactivity, was evaluated. Spatial working and reference memory were assessed in two aversively motivated learning and memory tasks: the standard and the "repeated acquisition" versions of the Morris water maze escape task, respectively. All rats were also tested in a passive avoidance task. At the end of the study, levels of serotonin (5-HT) and 5-hydroxyindoleacetic acid, and 5-HT turnover in the hippocampus and frontal cortex were determined. Strain differences showed a complex pattern across behavioral tests and serotonergic measures. Fischer 344 rats had the poorest performance in both versions of the Morris water escape task, whereas Brown Norway rats performed these tasks very well but the passive avoidance task poorly. Neither correlation analysis nor principal component analysis provided convincing support for the notion that OF, EPM, and cLDB tasks measure the same underlying trait. Our findings do not support the hypothesis that the level of emotional reactivity modulates cognitive performance in aversively motivated tasks. Concepts such as "emotional reactivity" and "learning and memory" cannot adequately be tapped with only one behavioral test. Our results emphasize the need for multiple testing.

ENU mutagenesis screening for dominant behavioral mutations based on normal control data obtained in home-cage activity, open-field, and passive avoidance tests.

PubMed

Wada, Yumiko; Furuse, Tamio; Yamada, Ikuko; Masuya, Hiroshi; Kushida, Tomoko; Shibukawa, Yoko; Nakai, Yuji; Kobayashi, Kimio; Kaneda, Hideki; Gondo, Yoichi; Noda, Tetsuo; Shiroishi, Toshihiko; Wakana, Shigeharu

2010-01-01

To establish the cutoff values for screening ENU-induced behavioral mutations, normal variations in mouse behavioral data were examined in home-cage activity (HA), open-field (OF), and passive-avoidance (PA) tests. We defined the normal range as one that included more than 95% of the normal control values. The cutoffs were defined to identify outliers yielding values that deviated from the normal by less than 5% for C57BL/6J, DBA/2J, DBF(1), and N(2) (DXDB) progenies. Cutoff values for G1-phenodeviant (DBF(1)) identification were defined based on values over +/- 3.0 SD from the mean of DBF(1) for all parameters assessed in the HA and OF tests. For the PA test, the cutoff values were defined based on whether the mice met the learning criterion during the 2nd (at a shock intensity of 0.3 mA) or the 3rd (at a shock intensity of 0.15 mA) retention test. For several parameters, the lower outliers were undetectable as the calculated cutoffs were negative values. Based on the cutoff criteria, we identified 275 behavioral phenodeviants among 2,646 G1 progeny. Of these, 64 were crossed with wild-type DBA/2J individuals, and the phenotype transmission was examined in the G2 progeny using the cutoffs defined for N(2) mice. In the G2 mice, we identified 15 novel dominant mutants exhibiting behavioral abnormalities, including hyperactivity in the HA or OF tests, hypoactivity in the OF test, and PA deficits. Genetic and detailed behavioral analysis of these ENU-induced mutants will provide novel insights into the molecular mechanisms underlying behavior.

Studies of learned helplessness in honey bees (Apis mellifera ligustica).

PubMed

Dinges, Christopher W; Varnon, Christopher A; Cota, Lisa D; Slykerman, Stephen; Abramson, Charles I

2017-04-01

The current study reports 2 experiments investigating learned helplessness in the honey bee (Apis mellifera ligustica). In Experiment 1, we used a traditional escape method but found the bees' activity levels too high to observe changes due to treatment conditions. The bees were not able to learn in this traditional escape procedure; thus, such procedures may be inappropriate to study learned helplessness in honey bees. In Experiment 2, we used an alternative punishment, or passive avoidance, method to investigate learned helplessness. Using a master and yoked design where bees were trained as either master or yoked and tested as either master or yoked, we found that prior training with unavoidable and inescapable shock in the yoked condition interfered with avoidance and escape behavior in the later master condition. Unlike control bees, learned helplessness bees failed to restrict their movement to the safe compartment following inescapable shock. Unlike learned helplessness studies in other animals, no decrease in general activity was observed. Furthermore, we did not observe a "freezing" response to inescapable aversive stimuli-a phenomenon, thus far, consistently observed in learned helplessness tests with other species. The bees, instead, continued to move back and forth between compartments despite punishment in the incorrect compartment. These findings suggest that, although traditional escape methods may not be suitable, honey bees display learned helplessness in passive avoidance procedures. Thus, regardless of behavioral differences from other species, honey bees can be a unique invertebrate model organism for the study of learned helplessness. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

Acquaintance Rape: Effective Avoidance Strategies.

ERIC Educational Resources Information Center

Levine-MacCombie, Joyce; Koss, Mary P.

1986-01-01

Determined that acknowledged and unacknowledged acquaintance rape victims and rape avoiders could be discriminated by situational variables and response strategies. Avoiders were less likely to have experienced passive or internalizing emotions at the time of the assault, perceived the assault as less violent, and were more likely to have utilized…

Passivation of bimetallic catalysts used in water treatment: prevention and reactivation.

PubMed

Chen, Jianming; Gillham, Robert W; Gui, Lai

2013-01-01

With respect to degradation rates and the range in contaminants treated, bimetals such as Ni-Fe or Pd-Fe generally outperform unamended granular iron. However, the catalytic enhancement is generally short-lived, lasting from a few days to months. To take advantage of the significant benefits of bimetals, this study aims at developing an effective method for the rejuvenation of passivated bimetals and alternatively, the prevention of rapid reactivity loss of bimetals. Because the most likely cause of Ni-Fe and Pd-Fe passivation is the deposition of iron oxide films over the catalyst sites, it is hypothesized that removal of the iron oxide films will restore the lost reactivity or avoiding the deposition of iron oxide films will prevent passivation. Two organic ligands (ethylenediaminetetraacetic acid (EDTA), and [s,s]-ethylenediaminedisuccinate acid ([s,s]-EDDS)) and two acids (citric acid and sulphuric acid) were tested as possible chemical reagents for both passivation rejuvenation and prevention. Trichloroethene (TCE) and Ni-Fe were chosen as probes for chlorinated solvents and bimetals respectively. The test was carried out using small glass columns packed with Ni-Fe. TCE solution containing a single reagent at various concentrations was pumped through the Ni-Fe columns with a residence time in the Ni-Fe of about 6.6 min. TCE concentrations in the influent and effluent were measured to evaluate the performance of each chemical reagent. The results show that (i) for passivated Ni-Fe, flushing with a low concentration of acid or ligand solution without mechanical mixing can fully restore the lost reactivity; and (ii) for passivation prevention, adding a small amount of a ligand or an acid to the feed solution can successfully prevent or at least substantially reduce Ni-Fe passivation. All four chemicals tested are effective in both rejuvenation and prevention, but sulphuric acid and citric acid are considered to be the most practical reagents due to their relatively low costs and environmentally friendly nature. This study suggests that the use of bimetals in above-groundwater treatment applications could become practical with appropriate engineering design.

Interactions between ACE inhibitors and classical antiepileptic drugs in the mouse maximal electroshock seizures.

PubMed

Łukawski, Krzysztof; Jakubus, Tomasz; Janowska, Agnieszka; Czuczwar, Stanisław J

2011-11-01

This study evaluated the effect of two angiotensin-converting enzyme (ACE) inhibitors, enalapril and cilazapril, commonly used antihypertensive drugs, on the protective efficacy of the classical antiepileptics - carbamazepine (CBZ), phenytoin (PHT), valproate (VPA) and phenobarbital (PB). For this purpose, we used the maximal electroshock seizure (MES) test in mice. Additionally, adverse effects of combined treatment with ACE inhibitors and antiepileptic drugs in the passive avoidance task and chimney test were assessed. All drugs were administered intraperitoneally. Neither enalapril (10, 20 and 30 mg/kg) nor cilazapril (5, 10 and 20mg/kg) affected the threshold for electroconvulsions. Enalapril (30 mg/kg) but not cilazapril (20mg/kg), enhanced the protective action of VPA, decreasing its ED(50) value from 249.5 to 164.9 mg/kg (p<0.01). Free plasma (non-protein-bound) and total brain concentrations of VPA were not significantly influenced by enalapril. Therefore, the observed interaction could be pharmacodynamic in nature. The combinations of ACE inhibitors with other antiepileptics (CBZ, PHT, and PB) were ineffective in that their ED(50) values against MES were not significantly changed. Enalapril and cilazapril remained ineffective as regards memory retention in the passive avoidance task or motor performance in the chimney test. The current study suggests that there are no negative interactions between the studied ACE inhibitors and classical antiepileptic drugs. Enalapril was even documented to enhance the anticonvulsant activity of VPA. Copyright © 2011 Elsevier Inc. All rights reserved.

Enhancing effects of chronic lithium on memory in the rat.

PubMed

Tsaltas, Eleftheria; Kontis, Dimitrios; Boulougouris, Vasileios; Papakosta, Vasiliki-Maria; Giannou, Haralambos; Poulopoulou, Cornelia; Soldatos, Constantine

2007-02-12

In spite of recent enrichment of neurochemical and behavioural data establishing a neuroprotective role for lithium, its primary effects on cognitive functioning remain ambiguous. This study examines chronic lithium effects on spatial working memory and long-term retention. In three discrete experiments, rats subjected to 30 daily intraperitoneal injections (2mmol/kg) of lithium (lithium groups: serum lithium=0.5+/-0.4mEq/l, 12h post-injection) or saline (controls) were trained in 0-s delay T-maze alternation and then tested in 30-, 45- and 60-s delay alternation (Experiments 1, 2, 3, respectively). Animals from Experiment 1 were further tested in one-trial step-through passive avoidance under mild shock parameters (0.5mA, 1s). Retention was assessed 6h later. Daily lithium or saline injections continued throughout behavioural testing. Lithium animals were indistinguishable from controls during 0-delay alternation baseline (Experiments 1-3, accuracy>88%) but showed significantly higher accuracy than controls at 30- and 45-s delays (93% versus 85% and 92% versus 82%, Experiments 1 and 2, respectively). At 60-s delay (Experiment 3) this beneficial effect of lithium was no longer apparent (lithium and control accuracy=78%). In Experiment 4, the shock used did not support 6-h passive avoidance retention in controls, whereas lithium animals showed significant step-through latency increases. Chronic lithium enhanced spatial working memory and promoted long-term retention of a weak aversive contingency. The results suggest that lithium may have potential as a cognitive enhancer.

Effects of dimethylaminoethanol pyroglutamate (DMAE p-Glu) against memory deficits induced by scopolamine: evidence from preclinical and clinical studies.

PubMed

Blin, Olivier; Audebert, Christine; Pitel, Séverine; Kaladjian, Arthur; Casse-Perrot, Catherine; Zaim, Mohammed; Micallef, Joelle; Tisne-Versailles, Jacky; Sokoloff, Pierre; Chopin, Philippe; Marien, Marc

2009-12-01

Dimethylaminoethanol pyroglutamate (DMAE p-Glu) is a compound resulting from the reaction between dimethylaminoethanol (an indirect precursor of acetylcholine) and pyroglutamic acid (a cyclic derivative of glutamic acid having procholinergic properties and promnesic effects in both animals and man). The present study undertook preclinical and clinical evaluations to test a potential therapeutic utility for DMAE p-Glu in cognitive impairments related to central cholinergic deficit. In preclinical study, DMAE p-Glu was studied in rats by intracerebral microdialysis in conscious freely moving animals, on performance of rats in the Morris water maze test of spatial memory, and on the deficit in passive avoidance behavior induced by scopolamine. The clinical study examined the effect of DMAE p-Glu on cognitive deficits induced by an intravenous injection of scopolamine in healthy young male subjects. In rat experiments, DMAE p-Glu increased the extracellular levels of choline and acetylcholine in the medial prefrontal cortex, as assessed by intracerebral microdialysis, improved performance in a test of spatial memory, and reduced scopolamine-induced memory deficit in passive avoidance behavior. Clinical study results show that scopolamine induced a memory deficit and that DMAE p-Glu produced a significant positive effect on scores in the Buschke test, as well as a slight but significant difference on choice reaction time. These results indicate that DMAE p-Glu reduces the deleterious effect of scopolamine on long-term memory in healthy volunteers and suggest that DMAE p-Glu might be effective in reducing memory deficits in patients with cognitive impairment.

Sexually dimorphic responses to neonatal basal forebrain lesions in mice: I. Behavior and neurochemistry.

PubMed

Arters, J; Hohmann, C F; Mills, J; Olaghere, O; Berger-Sweeney, J

1998-12-01

The nucleus basalis magnocellularis (nBM) provides the primary source of cholinergic input to the cortex. Neonatal lesions of the nBM produce transient reductions in cholinergic markers, persistent abnormalities in cortical morphology, and spatial navigation impairments in adult mice. The present study examined sex differences in the effects of an electrolytic nBM lesion on postnatal day 1 (PND 1) in mice on behavior and neurochemistry in adulthood. Mice were lesioned on PND 1 and tested at 8 weeks of age on a battery of behavioral tests including passive avoidance, cued and spatial tasks in the Morris water maze, simple and delayed nonmatch to sample versions of an odor discrimination task, and locomotor activity measurements. Following behavioral testing, mice were sacrificed for either morphological assessment or neurochemical analysis of a cholinergic marker or catecholamines. There were no lesion or sex differences in acquisition or retention of passive avoidance, performance of the odor discrimination tasks, or activity levels. Control mice showed a robust sex difference in performance of the spatial water maze task. The lesion produced a slight cued but more dramatic spatial navigation deficit in the water maze which affected only the male mice. Neurochemical analyses revealed no lesion-induced changes in either choline acetyltransferase activity or levels of norepinephrine or serotonin at the time of testing. The subsequent report shows a sex difference in lesion-induced changes in cortical morphology which suggests that sexually dimorphic cholinergic influences on cortical development are responsible for the behavioral deficits seen in this study.

Does Experiential Avoidance Mediate the Effects of Maladaptive Coping Styles on Psychopathology and Mental Health?

ERIC Educational Resources Information Center

Fledderus, Martine; Bohlmeijer, Ernst T.; Pieterse, Marcel E.

2010-01-01

Experiential avoidance (EA) is considered a risk factor for psychopathology. This study explores whether EA mediates the relationship between maladaptive coping styles (palliative, avoidance, and passive coping) and psychopathology and positive mental health. A total of 93 adults with mild to moderate psychological distress completed measures…

Behavioral methods for the study of the Ras-ERK pathway in memory formation and consolidation: passive avoidance and novel object recognition tests.

PubMed

d'Isa, Raffaele; Brambilla, Riccardo; Fasano, Stefania

2014-01-01

Memory is a high-level brain function that enables organisms to adapt their behavioral responses to the environment, hence increasing their probability of survival. The Ras-ERK pathway is a key molecular intracellular signalling cascade for memory consolidation. In this chapter we will describe two main one-trial behavioral tests commonly used in the field of memory research in order to assess the role of Ras-ERK signalling in long-term memory: passive avoidance and object recognition. Passive avoidance (PA) is a fear-motivated instrumental learning task, designed by Jarvik and Essman in 1960, in which animals learn to refrain from emitting a behavioral response that has previously been associated with a punishment. We will describe here the detailed protocol and show some examples of how PA can reveal impairments or enhancements in memory consolidation following loss or gain of function genetic manipulations of the Ras-ERK pathway. The phenotypes of global mutants as Ras-GRF1 KO, GENA53, and ERK1 KO mice, as well as of conditional region-specific mutants (striatal K-CREB mice), will be illustrated as examples. Novel object recognition (NOR), developed by Ennaceur and Delacour in 1988, is instead a more recent and highly ecological test, which relies on the natural tendency of rodents to spontaneously approach and explore novel objects, representing hence a useful non-stressful tool for the study of memory in animals without the employment of punishments or starvation/water restriction regimens. Careful indications will be given on how to select the positions for the novel object, in order to counterbalance for individual side preferences among mice during the training. Finally, the methods for calculating two learning indexes will be described. In addition to the classical discrimination index (DI) that measures the ability of an animal to discriminate between two different objects which are presented at the same time, we will describe the formula of a new index that we present here for the first time, the recognition index (RI), which quantifies the ability of an animal to recognize a same object at different time points and that, by taking into account the basal individual preferences displayed during the training, can give a more accurate measure of an animal's actual recognition memory.

Age Moderates the Effect of Acute Dopamine Depletion on Passive Avoidance Learning

PubMed Central

Kelm, Mary Katherine; Boettiger, Charlotte Ann

2015-01-01

Despite extensive links between reinforcement-based learning and dopamine (DA), studies to date have not found consistent effects of acute DA reduction on reinforcement learning in both men and women. Here, we tested the effects of reducing DA on reward- and punishment-based learning using the deterministic passive avoidance learning (PAL) task We tested 16 (5 female) adults (ages 22–40) in a randomized, cross-over design to determine whether reducing global DA by administering an amino acid beverage deficient in the DA precursors, phenylalanine and tyrosine (P/T[−]), would affect performance on the PAL task. We found that P/T[−] beverage effects on PAL performance were modulated by age. In particular, we found that P/T depletion significantly improved learning from punishment with increasing participant age. Participants committed 1.49 fewer passive avoidance errors per additional year of age (95% CI, −0.71 – −2.27, r=−0.74, p=0.001). Moreover, in this small sample, P/T depletion improved learning from punishment in adults (ages 26–40) while it impaired learning from punishment in emerging adults (ages 22–25). We observed similar, but non-significant trends in learning from reward. While there was no overall effect of P/T-depletion on reaction time (RT), there was a relationship between the effect of P/T depletion on PAL performance and RT; those who responded more slowly on the P/T[−] beverage also made more errors on the P/T[−] beverage. When P/T-depletion slowed RT after a correct response, there was a worsening of PAL task performance; there was no similar relationship for the RT after an incorrect response and PAL task performance. Moreover, among emerging adults, changes in mood on the P/T[−] beverage negatively correlated with learning from reward on the P/T[−] beverage. Together, we found that both reward- and punishment-based learning are sensitive to central catecholamine levels, and that these effects of acute DA reduction vary with age. PMID:25636601

PWZ-029, A COMPOUND WITH MODERATE INVERSE AGONIST FUNCTIONAL SELECTIVITY AT GABAA RECEPTORS CONTAINING α5 SUBUNITS, IMPROVES PASSIVE, BUT NOT ACTIVE, AVOIDANCE LEARNING IN RATS

PubMed Central

Savić, Miroslav M.; Clayton, Terry; Furtmüller, Roman; Gavrilović, Ivana; Samardžić, Janko; Savić, Snežana; Huck, Sigismund; Sieghart, Werner; Cook, James M.

2008-01-01

Benzodiazepine (BZ) site ligands affect vigilance, anxiety, memory processes, muscle tone and epileptogenic propensity through modulation of neurotransmission at GABAA receptors containing α1, α2, α3 or α5 subunits, and may have numerous experimental and clinical applications. The ability of nonselective BZ site inverse agonists to enhance cognition, documented in animal models and human studies, is clinically not feasible due to potentially unacceptable psychomotor effects. Most investigations to date have proposed the α1 and/or α5 subunit-containing GABAA receptors as comprising the memory-modulating population of these receptors. The novel ligand PWZ-029, which we synthesised and characterized electrophysiologically, possesses in vitro binding selectivity and moderate inverse agonist functional selectivity at α5-containing GABAA receptors. This ligand has also been examined in rats in the passive and active avoidance, spontaneous locomotor activity, elevated plus maze and grip strength tests, primarily predictive of the effects on the memory acquisition, basal locomotor activity, anxiety level and muscle tone, respectively. The improvement of task learning was detected at the dose of 5 mg/kg in the passive, but not active avoidance test. The inverse agonist PWZ-029 had no effect on anxiety or muscle tone, whereas at higher doses (10 and 20 mg/kg) it decreased locomotor activity. This effect was antagonized by flumazenil and also by the lower (but not the higher) dose of an agonist (SH-053-R-CH3-2’F) selective for GABAA receptors containing the α5 subunit. The hypolocomotor effect of PWZ-029 was not antagonized by the antagonist β-CCt exhibiting a preferential affinity for α1-subunit containing receptors. These data suggest that moderate negative modulation at GABAA receptors containing the α5 subunit is a sufficient condition for eliciting enhanced encoding/consolidation of declarative memory, while the influence of higher doses of modulators at these receptors on motor activity shows an intricate pattern whose relevance and mechanism await to be defined. PMID:18394590

[Study on corrosion resistance of three non-noble porcelain alloys].

PubMed

Wu, Zhikai; Xu, Sheng; Li, Wei; Teng, Jin; Li, Ning

2011-10-01

To study the electrochemical corrosion behavior of Co-Cr, Ni-Cr and Ni-Cr-Be based porcelain alloys in NaCl solution. Five samples of each alloy were made respectively, electric polarization curve of each alloy was obtained using potentiodynamic polarization technique. Self-corrosion potential (E(corr)), self-corrosion current density (I(corr), passive region and transpassivation potential were tested. Microstructure and constituent was examined using scanning electron microscopy and energy dispersive spectroscopy. Co-Cr alloy possessed the most desirable corrosion resistance because of its integrated, homogeneous and compact passive film. The poor compactness of Ni-Cr alloy's passive film decreased its corrosion resistance. Ni-Cr-Be alloy exhibited the worst corrosion resistance due to the Cr and Mo depleted Ni-Be eutectic phases in the alloy. Taking biological security into consideration, it is necessary to avoid the application of porcelain alloys with Be element. Co-Cr alloy with better biocompatibility possesses much broader prospect in the field of dental restoration.

Exercise preconditioning improves behavioral functions following transient cerebral ischemia induced by 4-vessel occlusion (4-VO) in rats.

PubMed

Tahamtan, Mahshid; Allahtavakoli, Mohammad; Abbasnejad, Mehdi; Roohbakhsh, Ali; Taghipour, Zahra; Taghavi, Mohsen; Khodadadi, Hassan; Shamsizadeh, Ali

2013-12-01

There is evidence that exercise decreases ischemia/reperfusion injury in rats. Since behavioral deficits are the main outcome in patients after stroke, our study was designed to investigate whether exercise preconditioning improves the acute behavioral functions and also brain inflammatory injury following cerebral ischemia. Male rats weighing 250-300 g were randomly allocated into five experimental groups. Exercise was performed on a treadmill 30min/day for 3 weeks. Ischemia was induced by 4-vessel occlusion method. Recognition memory was assessed by novel object recognition task (NORT) and step-through passive avoidance task. Sensorimotor function and motor movements were evaluated by adhesive removal test and ledged beam-walking test, respectively. Brain inflammatory injury was evaluated by histological assessment. In NORT, the discrimination ratio was decreased after ischemia (P < 0.05) and exercise preconditioning improved it in ischemic animals. In the passive avoidance test, a significant reduction in response latency was observed in the ischemic group. Exercise preconditioning significantly decreased the response latency in the ischemic rats (P < 0.001). In the adhesive removal test, latency to touch and remove the sticky labels from forepaw was increased following induction of ischemia (all P < 0.001) and exercise preconditioning decreased these indices compared to the ischemic group (all P < 0.001). In the ledged beam-walking test, the slip ratio was increased following ischemia (P < 0.05).  In the ischemia group, marked neuronal injury in hippocampus was observed. These neuropathological changes were attenuated by exercise preconditioning (P < 0.001). Our results showed that exercise preconditioning improves behavioral functions and maintains more viable cells in the dorsal hippocampus of the ischemic brain.

Emotional reactivity and cognitive performance in aversively motivated tasks: a comparison between four rat strains

PubMed Central

2009-01-01

Background Cognitive function might be affected by the subjects' emotional reactivity. We assessed whether behavior in different tests of emotional reactivity is correlated with performance in aversively motivated learning tasks, using four strains of rats generally considered to have a different emotional reactivity. Methods The performance of male Brown Norway, Lewis, Fischer 344, and Wistar Kyoto rats in open field (OF), elevated plus-maze (EPM), and circular light-dark preference box (cLDB) tasks, which are believed to provide measures of emotional reactivity, was evaluated. Spatial working and reference memory were assessed in two aversively motivated learning and memory tasks: the standard and the "repeated acquisition" versions of the Morris water maze escape task, respectively. All rats were also tested in a passive avoidance task. At the end of the study, levels of serotonin (5-HT) and 5-hydroxyindoleacetic acid, and 5-HT turnover in the hippocampus and frontal cortex were determined. Results Strain differences showed a complex pattern across behavioral tests and serotonergic measures. Fischer 344 rats had the poorest performance in both versions of the Morris water escape task, whereas Brown Norway rats performed these tasks very well but the passive avoidance task poorly. Neither correlation analysis nor principal component analysis provided convincing support for the notion that OF, EPM, and cLDB tasks measure the same underlying trait. Conclusions Our findings do not support the hypothesis that the level of emotional reactivity modulates cognitive performance in aversively motivated tasks. Concepts such as "emotional reactivity" and "learning and memory" cannot adequately be tapped with only one behavioral test. Our results emphasize the need for multiple testing. PMID:20003525

Implementing a Multiplexed System of Detectors for Higher Photon Counting Rates

DTIC Science & Technology

2007-01-01

D1 D2 Fig. 3. (a) Setup for testing different arrangements of InGaAs SPAD assemblies; (b) three different InGaAs SPAD assemblies; ( c ) schematic of...presently available, either commercial or prototype, the deadtimes range from ≈50 ns for actively quenched single photon avalanche detectors ( SPADs ...to ≈10 µs for passively quenched SPADs , although even actively quenched SPADs sometimes employ µs deadtimes to avoid excessive afterpulsing rates. In

Phytochemical analysis, antioxidant, antistress, and nootropic activities of aqueous and methanolic seed extracts of ladies finger (Abelmoschus esculentus L.) in mice.

PubMed

Doreddula, Sathish Kumar; Bonam, Srinivasa Reddy; Gaddam, Durga Prasad; Desu, Brahma Srinivasa Rao; Ramarao, Nadendla; Pandy, Vijayapandi

2014-01-01

Abelmoschus esculentus L. (ladies finger, okra) is a well-known tropical vegetable, widely planted from Africa to Asia and from South Europe to America. In the present study, we investigated the in vitro antioxidant capacity and in vivo protective effect of the aqueous and methanolic seed extracts of Abelmoschus esculentus against scopolamine-induced cognitive impairment using passive avoidance task and acute restraining stress-induced behavioural and biochemical changes using elevated plus maze (EPM) and forced swimming test (FST) in mice. Our results demonstrated that the pretreatment of mice with aqueous and methanolic seed extracts of Abelmoschus esculentus (200 mg/kg, p.o.) for seven days significantly (P < 0.01) attenuated scopolamine-induced cognitive impairment in the passive avoidance test. In addition, these extracts significantly reduced the blood glucose, corticosterone, cholesterol, and triglyceride levels elevated by acute restraint stress and also significantly increased the time spent in open arm in EPM and decreased the immobility time in FST. It has also been revealed that these extracts showed a significant antioxidant activity and no signs of toxicity or death up to a dose of 2000 mg/kg, p.o. These results suggest that the seed extracts of Abelmoschus esculentus L. possess antioxidant, antistress, and nootropic activities which promisingly support the medicinal values of ladies finger as a vegetable.

Phytochemical Analysis, Antioxidant, Antistress, and Nootropic Activities of Aqueous and Methanolic Seed Extracts of Ladies Finger (Abelmoschus esculentus L.) in Mice

PubMed Central

Doreddula, Sathish Kumar; Bonam, Srinivasa Reddy; Gaddam, Durga Prasad; Desu, Brahma Srinivasa Rao; Ramarao, Nadendla; Pandy, Vijayapandi

2014-01-01

Abelmoschus esculentus L. (ladies finger, okra) is a well-known tropical vegetable, widely planted from Africa to Asia and from South Europe to America. In the present study, we investigated the in vitro antioxidant capacity and in vivo protective effect of the aqueous and methanolic seed extracts of Abelmoschus esculentus against scopolamine-induced cognitive impairment using passive avoidance task and acute restraining stress-induced behavioural and biochemical changes using elevated plus maze (EPM) and forced swimming test (FST) in mice. Our results demonstrated that the pretreatment of mice with aqueous and methanolic seed extracts of Abelmoschus esculentus (200 mg/kg, p.o.) for seven days significantly (P < 0.01) attenuated scopolamine-induced cognitive impairment in the passive avoidance test. In addition, these extracts significantly reduced the blood glucose, corticosterone, cholesterol, and triglyceride levels elevated by acute restraint stress and also significantly increased the time spent in open arm in EPM and decreased the immobility time in FST. It has also been revealed that these extracts showed a significant antioxidant activity and no signs of toxicity or death up to a dose of 2000 mg/kg, p.o. These results suggest that the seed extracts of Abelmoschus esculentus L. possess antioxidant, antistress, and nootropic activities which promisingly support the medicinal values of ladies finger as a vegetable. PMID:25401145

Cognitive-Enhancing Effect of Aronia melanocarpa Extract against Memory Impairment Induced by Scopolamine in Mice

PubMed Central

Lee, Hyeon Yong; Weon, Jin Bae; Jung, Youn Sik; Kim, Nam Young; Kim, Myong Ki; Ma, Choong Je

2016-01-01

Aronia melanocarpa (A. melanocarpa) berries are a fruit with a marked antioxidant effect. The objective of this study was to confirm the effect of A. melanocarpa berries extract against scopolamine-induced memory impairment in mice using the Morris water maze and passive avoidance test. Moreover, we determined a possible mechanism of the cognitive-enhancing effect involving AChE activity and BDNF and p-CREB expression in the hippocampus of mice. A. melanocarpa berries extract attenuated the learning and memory impairment induced by scopolamine in the Morris water maze (79.3 ± 0.8 s of 200 mg/kg and 64.4 ± 10.7 s of 400 mg/kg on day 4) and passive avoidance tests (46.0 ± 41.1 s of 200 mg/kg and 25.6 ± 18.7 s of 400 mg/kg). A. melanocarpa berries extract reduced the acetylcholinesterase level in the hippocampus of scopolamine-injected mice and increased BDNF and p-CREB expression in the hippocampus. The major compound, cyanidin-3-O-galactoside, also reversed memory impairment. These results showed that A. melanocarpa berries extract improved memory impairment by inhibiting AChE and increasing BDNF and p-CREB expression, and cyanidin-3-O-galactoside may be responsible for the effect of A. melanocarpa berries extract. PMID:27239211

Cognitive-Enhancing Effect of Aronia melanocarpa Extract against Memory Impairment Induced by Scopolamine in Mice.

PubMed

Lee, Hyeon Yong; Weon, Jin Bae; Jung, Youn Sik; Kim, Nam Young; Kim, Myong Ki; Ma, Choong Je

2016-01-01

Aronia melanocarpa (A. melanocarpa) berries are a fruit with a marked antioxidant effect. The objective of this study was to confirm the effect of A. melanocarpa berries extract against scopolamine-induced memory impairment in mice using the Morris water maze and passive avoidance test. Moreover, we determined a possible mechanism of the cognitive-enhancing effect involving AChE activity and BDNF and p-CREB expression in the hippocampus of mice. A. melanocarpa berries extract attenuated the learning and memory impairment induced by scopolamine in the Morris water maze (79.3 ± 0.8 s of 200 mg/kg and 64.4 ± 10.7 s of 400 mg/kg on day 4) and passive avoidance tests (46.0 ± 41.1 s of 200 mg/kg and 25.6 ± 18.7 s of 400 mg/kg). A. melanocarpa berries extract reduced the acetylcholinesterase level in the hippocampus of scopolamine-injected mice and increased BDNF and p-CREB expression in the hippocampus. The major compound, cyanidin-3-O-galactoside, also reversed memory impairment. These results showed that A. melanocarpa berries extract improved memory impairment by inhibiting AChE and increasing BDNF and p-CREB expression, and cyanidin-3-O-galactoside may be responsible for the effect of A. melanocarpa berries extract.

Loganin enhances long-term potentiation and recovers scopolamine-induced learning and memory impairments.

PubMed

Hwang, Eun-Sang; Kim, Hyun-Bum; Lee, Seok; Kim, Min-Ji; Lee, Sung-Ok; Han, Seung-Moo; Maeng, Sungho; Park, Ji-Ho

2017-03-15

Although the incidence rate of dementia is rapidly growing in the aged population, therapeutic and preventive reagents are still suboptimal. Various model systems are used for the development of such reagents in which scopolamine is one of the favorable pharmacological tools widely applied. Loganin is a major iridoid glycoside obtained from Corni fructus (Cornusofficinalis et Zucc) and demonstrated to have anti-inflammatory, anti-tumor and osteoporosis prevention effects. It has also been found to attenuate Aβ-induced inflammatory reactions and ameliorate memory deficits induced by scopolamine. However, there has been limited information available on how loganin affects learning and memory both electrophysiologically and behaviorally. To assess its effect on learning and memory, we investigated the influence of acute loganin administration on long-term potentiation (LTP) using organotypic cultured hippocampal tissues. In addition, we measured the effects of loganin on the behavior performance related to avoidance memory, short-term spatial navigation memory and long-term spatial learning and memory in the passive avoidance, Y-maze, and Morris water maze learning paradigms, respectively. Loganin dose-dependently increased the total activity of fEPSP after high frequency stimulation and attenuated scopolamine-induced blockade of fEPSP in the hippocampal CA1 area. In accordance with these findings, loganin behaviorally attenuated scopolamine-induced shortening of step-through latency in the passive avoidance test, reduced the percent alternation in the Y-maze, and increased memory retention in the Morris water maze test. These results indicate that loganin can effectively block cholinergic muscarinic receptor blockade -induced deterioration of LTP and memory related behavioral performance. Based on these findings, loganin may aid in the prevention and treatment of Alzheimer's disease and learning and memory-deficit disorders in the future. Copyright © 2017 Elsevier Inc. All rights reserved.

Telencephalic neural activation following passive avoidance learning in a terrestrial toad.

PubMed

Puddington, Martín M; Daneri, M Florencia; Papini, Mauricio R; Muzio, Rubén N

2016-12-15

The present study explores passive avoidance learning and its neural basis in toads (Rhinella arenarum). In Experiment 1, two groups of toads learned to move from a lighted compartment into a dark compartment. After responding, animals in the experimental condition were exposed to an 800-mM strongly hypertonic NaCl solution that leads to weight loss. Control animals received exposure to a 300-mM slightly hypertonic NaCl solution that leads to neither weight gain nor loss. After 10 daily acquisition trials, animals in the experimental group showed significantly longer latency to enter the dark compartment. Additionally, 10 daily trials in which both groups received the 300-mM NaCl solution after responding eliminated this group effect. Thus, experimental animals showed gradual acquisition and extinction of a passive avoidance respond. Experiment 2 replicated the gradual acquisition effect, but, after the last trial, animals were sacrificed and neural activation was assessed in five brain regions using AgNOR staining for nucleoli-an index of brain activity. Higher activation in the experimental animals, relative to controls, was observed in the amygdala and striatum. Group differences in two other regions, lateral pallium and septum, were borderline, but nonsignificant, whereas group differences in the medial pallium were nonsignificant. These preliminary results suggest that a striatal-amygdala activation could be a key component of the brain circuit controlling passive avoidance learning in amphibians. The results are discussed in relation to the results of analogous experiments with other vertebrates. Copyright © 2016 Elsevier B.V. All rights reserved.

Aniracetam reverses memory impairment in rats.

PubMed

Martin, J R; Moreau, J L; Jenck, F

1995-02-01

The pyrrolidinone derivative aniracetam given orally immediately after acquisition of an inhibitory avoidance response reproducibly ameliorated scopolamine-induced amnesia in female rats in an extensive series of test sessions conducted over a 1-year period. In a dose-response experiment it was demonstrated that 50 mg kg-1 was the lowest oral dose of aniracetam to significantly ameliorate scopolamine-induced amnesia. Combined results from these numerous test sessions demonstrated that 50 mg kg-1 aniracetam administered to scopolamine-treated rats resulted in 53% of the animals exhibiting correct passive avoidance responding in the retention evaluation versus 9% of the scopolamine-treated rats given vehicle (in comparison, 64% of the rats injected with vehicle rather than scopolamine in this experimental situation exhibited correct responding in the retention test). There was minimal variation in this pattern of results over the successive 1-month blocks constituting the complete experimental period. Thus, the nootropic compound aniracetam replicably exhibited memory enhancing effects in this animal model of reduced cholinergic function.

Substituted piperazines as nootropic agents: 2- or 3-phenyl derivatives structurally related to the cognition-enhancer DM235.

PubMed

Guandalini, Luca; Martino, Maria Vittoria; Di Cesare Mannelli, Lorenzo; Bartolucci, Gianluca; Melani, Fabrizio; Malik, Ruchi; Dei, Silvia; Floriddia, Elisa; Manetti, Dina; Orlandi, Francesca; Teodori, Elisabetta; Ghelardini, Carla; Romanelli, Maria Novella

2015-04-15

A series of 2-phenyl- or 3-phenyl piperazines, structurally related to DM235 and DM232, two potent nootropic agents, have been prepared and tested in the mouse passive-avoidance test, to assess their ability to revert scopolamine-induced amnesia. Although the newly synthesized molecules were less potent than the parent compounds, some useful information has been obtained from structure-activity relationships. A small but significant enantioselectivity has been found for the most potent compound 5a. Copyright © 2015 Elsevier Ltd. All rights reserved.

Design, synthesis, and preliminary pharmacological evaluation of 1, 4-diazabicyclo[4.3.0]nonan-9-ones as a new class of highly potent nootropic agents.

PubMed

Manetti, D; Ghelardini, C; Bartolini, A; Bellucci, C; Dei, S; Galeotti, N; Gualtieri, F; Romanelli, M N; Scapecchi, S; Teodori, E

2000-05-18

Several 4-substituted 1,4-diazabicyclo[4.3.0]nonan-9-ones have been synthesized and tested in vivo on mouse passive avoidance test, to evaluate their nootropic activity. The results show that they represent a new class of nootropic drugs with a pharmacological profile very similar to that of piracetam, showing much higher potency with respect to the reference. Among the compounds studied, 7 (DM 232) shows outstanding potency, being active at the dose of 0. 001 mg kg(-1) sc.

90-Day Inhalation Toxicity Study of Swedish Biofuel Alcohol-to-Jet (ATJ) Synthetic Kerosene with Aromatics (SPA) in Rats with Neurotoxicity Testing and Genotoxicity Assay

DTIC Science & Technology

2015-09-01

activity, passive avoidance or Morris water maze performance. However, differences were found in a test for behavioral sensitization. The appetitive...Daily Consumption 10.25 Tuesday Wednesday Thursday Friday 10/2/2012 10/3/2012 10/4/2012 10/5/2012 10/2/2012 10/3/2012 10/4/2012 10/5/2012 Tuesday ...Wednesday Thursday Friday 10/2/2012 10/3/2012 10/4/2012 10/5/2012 Tuesday Wednesday Thursday Friday Tuesday Wednesday Thursday Friday Weekend & Holiday 10/2

Naringenin improves learning and memory in an Alzheimer's disease rat model: Insights into the underlying mechanisms.

PubMed

Ghofrani, Saeed; Joghataei, Mohammad-Taghi; Mohseni, Simin; Baluchnejadmojarad, Tourandokht; Bagheri, Maryam; Khamse, Safoura; Roghani, Mehrdad

2015-10-05

Alzheimer's disease (AD) is one of the prevalent neurological disorders of the central nervous system hallmarked by increased beta-amyloid (Aβ) deposition and ensuing learning and memory deficit. In the present study, the beneficial effect of naringenin on improvement of learning and memory was evaluated in an Alzheimer's disease rat model. The Aβ-injected rats showed a lower alternation score in Y-maze task, impairment of retention and recall capability in passive avoidance test, and lower correct choices and higher errors in radial arm maze (RAM) task as compared to sham group in addition to enhanced oxidative stress and apoptosis. Naringenin, but not a combination of naringenin and fulvestrant (an estrogenic receptor antagonist) significantly improved the performance of Aβ-injected rats in passive avoidance and RAM tasks. Naringenin pretreatment of Aβ-injected rats also lowered hippocampal malondialdehyde (MDA) with no significant effect on nitrite and superoxide dismutase (SOD) activity in addition to lowering apoptosis. These results suggest naringenin pretreatment attenuates Aβ-induced impairment of learning and memory through mitigation of lipid peroxidation and apoptosis and its beneficial effect is somewhat mediated via estrogenic pathway. Copyright © 2015 Elsevier B.V. All rights reserved.

Brain-derived neurotrophic factor transgenic mice exhibit passive avoidance deficits, increased seizure severity and in vitro hyperexcitability in the hippocampus and entorhinal cortex.

PubMed

Croll, S D; Suri, C; Compton, D L; Simmons, M V; Yancopoulos, G D; Lindsay, R M; Wiegand, S J; Rudge, J S; Scharfman, H E

1999-01-01

Transgenic mice overexpressing brain-derived neurotrophic factor from the beta-actin promoter were tested for behavioral, gross anatomical and physiological abnormalities. Brain-derived neurotrophic factor messenger RNA overexpression was widespread throughout brain. Overexpression declined with age, such that levels of overexpression decreased sharply by nine months. Brain-derived neurotrophic factor transgenic mice had no gross deformities or behavioral abnormalities. However, they showed a significant passive avoidance deficit. This deficit was dependent on continued overexpression, and resolved with age as brain-derived neurotrophic factor transcripts decreased. In addition, the brain-derived neurotrophic factor transgenic mice showed increased seizure severity in response to kainic acid. Hippocampal slices from brain-derived neurotrophic factor transgenic mice showed hyperexcitability in area CA3 and entorhinal cortex, but not in dentate gyrus. Finally, area CA1 long-term potentiation was disrupted, indicating abnormal plasticity. Our data suggest that overexpression of brain-derived neurotrophic factor in the brain can interfere with normal brain function by causing learning impairments and increased excitability. The results also support the hypothesis that excess brain-derived neurotrophic factor could be pro-convulsant in the limbic system.

Toll-Like Receptor 4 Deficiency Causes Reduced Exploratory Behavior in Mice Under Approach-Avoidance Conflict.

PubMed

Li, Chunlu; Yan, Yixiu; Cheng, Jingjing; Xiao, Gang; Gu, Jueqing; Zhang, Luqi; Yuan, Siyu; Wang, Junlu; Shen, Yi; Zhou, Yu-Dong

2016-04-01

Abnormal approach-avoidance behavior has been linked to deficits in the mesolimbic dopamine (DA) system of the brain. Recently, increasing evidence has indicated that toll-like receptor 4 (TLR4), an important pattern-recognition receptor in the innate immune system, can be directly activated by substances of abuse, resulting in an increase of the extracellular DA level in the nucleus accumbens. We thus hypothesized that TLR4-dependent signaling might regulate approach-avoidance behavior. To test this hypothesis, we compared the novelty-seeking and social interaction behaviors of TLR4-deficient (TLR4(-/-)) and wild-type (WT) mice in an approach-avoidance conflict situation in which the positive motivation to explore a novel object or interact with an unfamiliar mouse was counteracted by the negative motivation to hide in exposed, large spaces. We found that TLR4(-/-) mice exhibited reduced novelty-seeking and social interaction in the large open spaces. In less stressful test apparatuses similar in size to the mouse cage, however, TLR4(-/-) mice performed normally in both novelty-seeking and social interaction tests. The reduced exploratory behaviors under approach-avoidance conflict were not due to a high anxiety level or an enhanced fear response in the TLR4(-/-) mice, as these mice showed normal anxiety and fear responses in the open field and passive avoidance tests, respectively. Importantly, the novelty-seeking behavior in the large open field induced a higher level of c-Fos activation in the nucleus accumbens shell (NAcSh) in TLR4(-/-) mice than in WT mice. Partially inactivating the NAcSh via infusion of GABA receptor agonists restored the novelty-seeking behavior of TLR4(-/-) mice. These data suggested that TLR4 is crucial for positive motivational behavior under approach-avoidance conflict. TLR4-dependent activation of neurons in the NAcSh may contribute to this phenomenon.

Now You See it, Now You Don't: Age Differences in Affective Reactivity to Social Tensions

PubMed Central

Charles, Susan Turk; Piazza, Jennifer R.; Luong, Gloria; Almeida, David M.

2009-01-01

When faced with interpersonal conflict, older adults report using passive strategies more often than do younger adults. They also report less affective reactivity in response to these tensions. We examined whether the use of passive strategies may explain age-related reductions in affective reactivity to interpersonal tensions. Over eight consecutive evenings, participants (N = 1031, 25 – 74 years-old) reported daily negative affect and the occurrence of tense situations where they had an argument or avoided an argument. Older age was related to less affective reactivity when people decided to avoid an argument but was unrelated to affective reactivity when people engaged in arguments. Findings suggest that avoidance of negative situations may largely underlie age-related benefits in affective well-being. PMID:19739920

Impairment of learning and memory after photothrombosis of the prefrontal cortex in rat brain: effects of Noopept.

PubMed

Romanova, G A; Shakova, F M; Gudasheva, T A; Ostrovskaya, R U

2002-12-01

Experiments were performed on rats trained conditioned passive avoidance response. Acquisition and retention of memory traces were impaired after photothrombosis of the prefrontal cortex. The acyl-prolyl-containing dipeptide Noopept facilitated retention and retrieval of a conditioned passive avoidance response, normalized learning capacity in animals with ischemic damage to the cerebral cortex, and promoted finish training in rats with hereditary learning deficit. These results show that Noopept improves all three stages of memory. It should be emphasized that the effect of Noopept was most pronounced in animals with impaired mnesic function.

Sensor Management for Tactical Surveillance Operations

DTIC Science & Technology

2007-11-01

active and passive sonar for submarine and tor- pedo detection, and mine avoidance. [range, bearing] range 1.8 km to 55 km Active or Passive AN/SLQ-501...finding (DF) unit [bearing, classification] maximum range 1100 km Passive Cameras (day- light/ night- vision) ( video & still) Record optical and...infrared still images or motion video of events for near-real time assessment or long term analysis and archiving. Range is limited by the image resolution

Effect of Combined Treatment with AT1 Receptor Antagonists and Tiagabine on Seizures, Memory and Motor Coordination in Mice.

PubMed

Łukawski, Krzysztof; Janowska, Agnieszka; Czuczwar, Stanisław J

2015-01-01

Losartan and telmisartan, angiotensin AT1 receptor antagonists, are widely used antihypertensive drugs in patients. It is also known that arterial hypertension is often present in people with epilepsy, therefore, drug interactions between AT1 receptor antagonists and antiepileptic drugs can occur in clinical practice. The aim of the current study was to assess the effect of losartan and telmisartan on the anticonvulsant activity of tiagabine, a second-generation antiepileptic drug, in mice. Additionally, the effect of the combined treatment with AT1 receptor antagonists and TGB on long-term memory and motor coordination has been assessed in animals. The study was performed on male Swiss mice. Convulsions were examined in the maximal electroshock seizure threshold test. Long-term memory was measured in the passive-avoidance task and motor coordination was evaluated in the chimney test. AT1 receptor antagonists and TGB were administered intraperitoneally. Losartan (50 mg/kg) or telmisartan (30 mg/kg) did not influence the anticonvulsant activity of TGB applied at doses of 2, 4 and 6 mg/kg. However, both AT1 receptor antagonists in combinations with TGB (6 mg/kg) impaired motor coordination in the chimney test. The concomitant treatment of the drugs did not decrease retention in the passive avoidance task. It is suggested that losartan and telmisartan should not affect the anticonvulsant action of TGB in people with epilepsy. Because the combined treatment with AT1 receptor antagonists and TGB led to neurotoxic effects in animals, caution is advised during concomitant use of these drugs in patients.

Intermittent ethanol exposure increases long-lasting behavioral and neurochemical effects of MDMA in adolescent mice.

PubMed

Rodríguez-Arias, Marta; Maldonado, Concepción; Vidal-Infer, Antonio; Guerri, Consuelo; Aguilar, María A; Miñarro, José

2011-11-01

Heavy binge drinking is increasingly frequent among adolescents, while ethanol (EtOH) is often used in combination with 3,4-methylenedioxymethamphetamine (MDMA). The long-lasting effects of intermittent exposure to EtOH and MDMA during adolescence on motor activity, anxiety, and social behavior were evaluated in adult mice. The concentration of brain monoamines in the striatum, cortex, and hippocampus was measured following the behavioral test. Adolescent OF1 mice were exposed to ethanol (1.25 g/kg) on two consecutive days at 48-h intervals over a 14-day period (from PND 29 to 42). A total of eight injections of MDMA (10 or 20 mg/kg) were administered twice daily at 4-h intervals over two consecutive days, and this schedule was repeated 6 days later (PND 33, 34, 41, and 42). Behavioral tests and analysis of brain monoamines took place on PND 64 to 67. Exposure to MDMA during adolescence increased the anxiogenic response in the elevated plus maze, with adult mice spending less time in the open arms of the maze and exhibiting lower concentrations of DA in the striatum. A pattern of ethanol administration modeling binge drinking during adolescence enhanced these effects and undermined the hyperthermic response induced by MDMA. Passive avoidance was affected only when EtOH was administered alone. Juvenile administration of MDMA and alcohol was found to cause a decrease in monoamine levels in adulthood, as well as changes in social interaction behaviors, locomotor activity, increase measures of anxiety in the elevated plus maze (EPM), and decrease step-through latencies in passive avoidance test.

Loss of Hippocampal Neurons after Kainate Treatment Correlates with Behavioral Deficits

PubMed Central

Maia, Gisela H.; Quesado, José L.; Soares, Joana I.; do Carmo, Joana M.; Andrade, Pedro A.; Andrade, José P.; Lukoyanov, Nikolai V.

2014-01-01

Treating rats with kainic acid induces status epilepticus (SE) and leads to the development of behavioral deficits and spontaneous recurrent seizures later in life. However, in a subset of rats, kainic acid treatment does not induce overt behaviorally obvious acute SE. The goal of this study was to compare the neuroanatomical and behavioral changes induced by kainate in rats that developed convulsive SE to those who did not. Adult male Wistar rats were treated with kainic acid and tested behaviorally 5 months later. Rats that had experienced convulsive SE showed impaired performance on the spatial water maze and passive avoidance tasks, and on the context and tone retention tests following fear conditioning. In addition, they exhibited less anxiety-like behaviors than controls on the open-field and elevated plus-maze tests. Histologically, convulsive SE was associated with marked neuron loss in the hippocampal CA3 and CA1 fields, and in the dentate hilus. Rats that had not experienced convulsive SE after kainate treatment showed less severe, but significant impairments on the spatial water maze and passive avoidance tasks. These rats had fewer neurons than control rats in the dentate hilus, but not in the hippocampal CA3 and CA1 fields. Correlational analyses revealed significant relationships between spatial memory indices of rats and neuronal numbers in the dentate hilus and CA3 pyramidal field. These results show that a part of the animals that do not display intense behavioral seizures (convulsive SE) immediately after an epileptogenic treatment, later in life, they may still have noticeable structural and functional changes in the brain. PMID:24409306

Effect of 'chronic' versus 'acute' ketamine administration and its 'withdrawal' effect on behavioural alterations in mice: implications for experimental psychosis.

PubMed

Chatterjee, Manavi; Ganguly, Surajit; Srivastava, Mukesh; Palit, Gautam

2011-01-01

Lack of appropriate animal models simulating core behavioural aspects of human psychosis is a major limitation in schizophrenia research. The use of drugs, that is believed to act through N-methyl d-aspartate receptor, has been demonstrated to mimic relatively broader range of behavioural symptoms in putative animal models. Our goal in this study has been to further evaluate one such drug, ketamine in mice and characterize some selective behavioural phenotypes associated with the drug dosage, treatment period and withdrawal effects to extend the understanding of this model. Our results indicate that acute treatment of ketamine (100 mg/kg, i.p.) induced hyperlocomotory response and reduced the 'transfer-latency time' in passive avoidance test but did not have any effect in the forced swim test (negative symptoms). In contrast, chronic administration of ketamine not only produced significant 'hyperactivity' response but also enhanced the immobility period in animals during the forced swim test and reduced the latency period in the passive avoidance test. Further, these behavioural alterations persisted at least for 10 days after the withdrawal of ketamine treatment. These observations were substantiated by using standard typical and atypical antipsychotic drugs, haloperidol (0.25 mg/kg, i.p.), clozapine (10 mg/kg, i.p.) and risperidone (0.025 mg/kg, i.p.). Therefore, the present study suggests that the chronic treatment with ketamine has the potential of exhibiting changes in broader range of behavioural domains than the acute treatment. Hence, animals chronically treated with ketamine might serve as a useful tool to study the underlying pathogenic mechanisms associated with some symptoms in schizophrenia and other psychiatric disorders. Copyright © 2010 Elsevier B.V. All rights reserved.

In defense of the passive voice in medical writing.

PubMed

Minton, Timothy D

2015-01-01

Few medical journals specifically instruct authors to use the active voice and avoid the passive voice, but advice to that effect is common in the large number of stylebooks and blogs aimed at medical and scientific writers. Such advice typically revolves around arguments that the passive voice is less clear, less direct, and less concise than the active voice, that it conceals the identity of the person(s) performing the action(s) described, that it obscures meaning, that it is pompous, and that the high rate of passive-voice usage in scientific writing is a result of conformity to an established and old-fashioned style of writing. Some of these arguments are valid with respect to specific examples of passive-voice misuse by some medical (and other) writers, but as arguments for avoiding passive-voice use in general, they are seriously flawed. In addition, many of the examples that stylebook writers give of inappropriate use are actually much more appropriate in certain contexts than the active-voice alternatives they provide. In this review, I examine the advice offered by anti-passive writers, along with some of their examples of "inappropriate" use, and argue that the key factor in voice selection is sentence word order as determined by the natural tendency in English for the topic of discourse ("old" information) to take subject position and for "new" information to come later. Authors who submit to this natural tendency will not have to worry much about voice selection, because it will usually be automatic.

Gyro-effect stabilizes unstable permanent maglev centrifugal pump.

PubMed

Qian, Kun-Xi

2007-03-01

According to Earnshaw's Theorem (1839), the passive maglev cannot achieve stable equilibrium and thus an extra coil is needed to make the rotor electrically levitated in a heart pump. The author had developed a permanent maglev centrifugal pump utilizing only passive magnetic bearings, to keep the advantages but to avoid the disadvantages of the electric maglev pumps. The equilibrium stability was achieved by use of so-called "gyro-effect": a rotating body with certain high speed can maintain its rotation stably. This pump consisted of a rotor (driven magnets and an impeller), and a stator with motor coil and pump housing. Two passive magnetic bearings between rotor and stator were devised to counteract the attractive force between the motor coil iron core and the rotor driven magnets. Bench testing with saline demonstrated a levitated rotor under preconditions of higher than 3,250 rpm rotation and more than 1 l/min pumping flow. Rotor levitation was demonstrated by 4 Hall sensors on the stator, with evidence of reduced maximal eccentric distance from 0.15 mm to 0.07 mm. The maximal rotor vibration amplitude was 0.06 mm in a gap of 0.15 mm between rotor and stator. It concluded that Gyro-effect can help passive maglev bearings to achieve stabilization of permanent maglev pump; and that high flow rate indicates good hydraulic property of the pump, which helps also the stability of passive maglev pump.

Behavioral Alterations in Response to Fear-Provoking Stimuli and Tranylcypromine Induced by Perinatal Exposure to Bisphenol A and Nonylphenol in Male Rats

PubMed Central

Negishi, Takayuki; Kawasaki, Katsuyoshi; Suzaki, Shingo; Maeda, Haruna; Ishii, Yoshiyuki; Kyuwa, Shigeru; Kuroda, Yoichiro; Yoshikawa, Yasuhiro

2004-01-01

The purpose of this study was to examine whether perinatal exposure to two major environmental endocrine-disrupting chemicals, bisphenol A (BPA; 0.1 mg/kg/day orally) and nonylphenol [NP; 0.1 mg/kg/day (low dose) and 10 mg/kg/day (high dose) orally] daily from gestational day 3 to postnatal day 20 (transplacental and lactational exposures) would lead to behavioral alterations in the male offspring of F344 rats. Neither BPA nor NP exposure affected behavioral characteristics in an open-field test (8 weeks of age), in a measurement of spontaneous motor activity (12 weeks of age), or in an elevated plus-maze test (14 weeks of age). A passive avoidance test (13 weeks of age) showed that both BPA- and NP-treated offspring tended to delay entry into a dark compartment. An active avoidance test at 15 weeks of age revealed that BPA-treated offspring showed significantly fewer avoidance responses and low-dose NP-treated offspring exhibited slightly fewer avoidance responses. Furthermore, BPA-treated offspring significantly increased the number of failures to avoid electrical unconditioned stimuli within 5-sec electrical shock presentation compared with the control offspring. In a monoamine-disruption test using 5 mg/kg (intraperitoneal) tranylcypromine (Tcy), a monoamine oxidase inhibitor, both BPA-treated and low-dose NP-treated offspring at 22–24 weeks of age failed to show a significant increment in locomotion in response to Tcy, whereas control and high-dose NP-treated offspring significantly increased locomotion behavior after Tcy injection. In addition, when only saline was injected during a monoamine-disruption test, low-dose NP-treated offspring showed frequent rearing compared with the control offspring. The present results indicate that perinatal low-dose BPA or NP exposure irreversibly influenced the reception of fear-provoking stimuli (e.g., electrical shock), as well as monoaminergic neural pathways. PMID:15289160

[Interventions on the exposure of non-smoking pregnant women to passive smoking].

PubMed

Yao, Ting-ting; Chen, Xue-yun; Hu, De-wei; Mao, Zheng-zhong

2008-09-01

To investigate the extent of exposure of non-smoking pregnant women to passive smoking; to undertake interventions on the knowledge, attitudes and behaviors of those women toward passive smoking; and to evaluate the effectiveness of the interventions. A total of 128 non-smoking pregnant women participated in the survey. Their knowledge, attitudes and behaviors towards passive smoking were measured by a self-administered questionnaire. A sixteen-week intervention was undertaken. The knowledge and attitudes of the non-smoking pregnant women towards passive smoking improved significantly, as well as their attempts to avoid exposure to the passive smoking brought by their smoking husbands or other family members. Telephone counseling, booklets and doctors' advices were the most acceptable approaches of health education. The comprehensive interventions are effective for improving the knowledge, attitudes and behaviors of non-smoking women toward passive smoking.

Vitex Agnus Castus Extract Improves Learning and Memory and Increases the Transcription of Estrogen Receptor α in Hippocampus of Ovariectomized Rats.

PubMed

Allahtavakoli, Mohammad; Honari, Najmeh; Pourabolli, Iran; Kazemi Arababadi, Mohammad; Ghafarian, Hossein; Roohbakhsh, Ali; Esmaeili Nadimi, Ali; Shamsizadeh, Ali

2015-07-01

Lower level of estrogen hormone is considered as an important factor for loss of learning and memory in postmenopausal women. Although estrogen replacement therapy is used for compensation, but long-term usage of estrogen is associated with a higher risk of hormone-dependent cancers. Phytoestrogens, due to fewer side effects, have been proposed to prevent menopause-related cognitive decline. 24 female Wistar rats weighing 180-220 g were used in this study. The animals were ovariectomized and randomly divided into four groups including, control and two groups which received 8 and 80 mg/kg Vitex agnus castus (VAC) ethanolic extract orally. The last groups were treated with 40 μg/kg of estradiol valerat. Step-through passive avoidance (STPA) test was used for the evaluation of learning and memory. The hippocampal estrogen receptor α (ERα) expression was measured using Real-Time PCR. The results demonstrated that VAC extract or estradiol had better performance on step-through passive avoidance test than control group (all P<0.05). Moreover, administration of either estradiol or VAC extract increased the hippocampal mRNA level of ERα and prevented the decrease in uterine weight of ovariectomized rats. Based on our data, VAC extract improves learning and memory in ovariectomized rats. The positive effect of VAC extract on learning and memory is possibly associated with an increase in ERα gene expression in the hippocampal formation.

Effects of cholestasis on learning and locomotor activity in bile duct ligated rats.

PubMed

Hosseini, Nasrin; Alaei, Hojjatallah; Nasehi, Mohammad; Radahmadi, Maryam; Mohammad Reza, Zarrindast

2014-01-01

Cognitive functions are impaired in patients with liver disease. Bile duct ligation causes cholestasis that impairs liver function. This study investigated the impact of cholestasis progression on the acquisition and retention times in the passive avoidance test and on the locomotor activity of rats. Cholestasis was induced in male Wistar rats by ligating the main bile duct. Locomotor activity, learning and memory were assessed by the passive avoidance learning test at day 7, day 14, and day 21 post-bile duct ligation. The serum levels of bilirubin, alanine aminotransferase, and alkaline phosphatase were measured. The results showed that acquisition time and locomotor activity were not affected at day 7 and day 14, but they were significantly (P < 0.05) impaired at day 21 post-bile duct ligation compared with the results for the control group. Additionally, memory was significantly impaired on day 7 (P < 0.01), day 14, and day 21 (P < 0.001) compared with the control groups. The levels of total bilirubin, direct bilirubin, indirect bilirubin, alanine aminotransferase, and alkaline phosphatase were significantly higher at day 7, day 14, and day 21 post-bile duct ligation compared with the levels in the sham group. Based on these findings, both liver and memory function were affected in the early stage of cholestasis (7 days after bile duct ligation), while learning and locomotor activity were impaired at 21 days after bile duct ligation following the progression of cholestasis.

The effects of DHEA, 3beta-hydroxy-5alpha-androstane-6,17-dione, and 7-amino-DHEA analogues on short term and long term memory in the mouse.

PubMed

Bazin, Marc-Antoine; El Kihel, Laïla; Boulouard, Michel; Bouët, Valentine; Rault, Sylvain

2009-11-01

Neurosteroids have been reported to modulate memory processes in rodents. Three analogues of dehydroepiandrosterone (DHEA), two of them previously described (7beta-aminoDHEA and 7beta-amino-17-ethylenedioxy-DHEA), and a new one (3beta-hydroxy-5alpha-androstane-6,17-dione) were synthesized, and their effects were evaluated on memory. This study examined their effects on long term and short term memory in male (6 weeks old) NMRI mice in comparison with the reference drug. Long term memory was assessed using the passive avoidance task and short term memory (spatial working memory) using the spontaneous alternation task in a Y maze. Moreover, the effects of DHEA and its analogues on spontaneous locomotion were measured. In all tests, DHEA and analogues were injected at three equimolar doses (0.300-1.350-6.075 microM/kg). DHEA and its three analogues administered immediately post-training at the highest doses (6.075 microM/kg, s.c.) improved retention in passive avoidance test. Without effect per se in the spatial working memory task, the four compounds failed to reverse scopolamine (1mg/kg, i.p.)-induced deficit in spontaneous alternation. These data suggested an action of DHEA and analogues in consolidation of long term memory particularly when emotional components are implied. Moreover, data indicated that pharmacological modulation of DHEA as performed in this study provides derivatives giving the same mnemonic profile than reference molecule.

Vitex Agnus Castus Extract Improves Learning and Memory and Increases the Transcription of Estrogen Receptor α in Hippocampus of Ovariectomized Rats

PubMed Central

Allahtavakoli, Mohammad; Honari, Najmeh; Pourabolli, Iran; Kazemi Arababadi, Mohammad; Ghafarian, Hossein; Roohbakhsh, Ali; Esmaeili Nadimi, Ali; Shamsizadeh, Ali

2015-01-01

Introduction: Lower level of estrogen hormone is considered as an important factor for loss of learning and memory in postmenopausal women. Although estrogen replacement therapy is used for compensation, but long-term usage of estrogen is associated with a higher risk of hormone-dependent cancers. Phytoestrogens, due to fewer side effects, have been proposed to prevent menopause-related cognitive decline. Methods: 24 female Wistar rats weighing 180–220 g were used in this study. The animals were ovariectomized and randomly divided into four groups including, control and two groups which received 8 and 80 mg/kg Vitex agnus castus (VAC) ethanolic extract orally. The last groups were treated with 40 μg/kg of estradiol valerat. Step-through passive avoidance (STPA) test was used for the evaluation of learning and memory. The hippocampal estrogen receptor α (ERα) expression was measured using Real-Time PCR. Results: The results demonstrated that VAC extract or estradiol had better performance on step-through passive avoidance test than control group (all P<0.05). Moreover, administration of either estradiol or VAC extract increased the hippocampal mRNA level of ERα and prevented the decrease in uterine weight of ovariectomized rats. Discussion: Based on our data, VAC extract improves learning and memory in ovariectomized rats. The positive effect of VAC extract on learning and memory is possibly associated with an increase in ERα gene expression in the hippocampal formation. PMID:26904176

Neuropathological changes in brain cortex and hippocampus in a rat model of Alzheimer's disease.

PubMed

Nobakht, Maliheh; Hoseini, Seyed Mohammad; Mortazavi, Pejman; Sohrabi, Iraj; Esmailzade, Banafshe; Rahbar Rooshandel, Nahid; Omidzahir, Shila

2011-01-01

Alzheimer's disease (AD) is a neurodegenerative disorder with progressive loss of cognitive abilities and memory loss. The aim of this study was to compare neuropathological changes in hippocampus and brain cortex in a rat model of AD. Adult male Albino Wistar rats (weighing 250-300 g) were used for behavioral and histopathological studies. The rats were randomly assigned to three groups: control, sham and Beta amyloid (ABeta) injection. For behavioral analysis, Y-maze and shuttle box were used, respectively at 14 and 16 days post-lesion. For histological studies, Nissl, modified Bielschowsky and modified Congo red staining were performed. The lesion was induced by injection of 4 muL of ABeta (1-40) into the hippocampal fissure. In the present study, ABeta (1-40) injection into hippocampus could decrease the behavioral indexes and the number of CA1 neurons in hippocampus. ABeta injection CA1 caused ABeta deposition in the hippocampus and less than in cortex. We observed the loss of neurons in the hippocampus and cerebral cortex and certain subcortical regions. Y-maze test and single-trial passive avoidance test showed reduced memory retention in AD group. We found a significant decreased acquisition of passive avoidance and alternation behavior responses in AD group compared to control and sham group (P<0.0001). Compacted amyloid cores were present in the cerebral cortex, hippocampus and white matter, whereas, scattered amyloid cores were seen in cortex and hippocampus of AD group. Also, reduced neuronal density was indicated in AD group.

Lack of promoter IV-driven BDNF transcription results in depression-like behavior.

PubMed

Sakata, K; Jin, L; Jha, S

2010-10-01

Transcription of Bdnf is controlled by multiple promoters, in which promoter IV contributes significantly to activity-dependent Bdnf transcription. We have generated promoter IV mutant mice [brain-derived neurotrophic factor (BDNF)-KIV] in which promoter IV-driven expression of BDNF is selectively disrupted by inserting a green fluorescent protein (GFP)-STOP cassette within the Bdnf exon IV locus. BDNF-KIV animals exhibited depression-like behavior as shown by the tail suspension test (TST), sucrose preference test (SPT) and learned helplessness test (LHT). In addition, BDNF-KIV mice showed reduced activity in the open field test (OFT) and reduced food intake in the novelty-suppressed feeding test (NSFT). The mutant mice did not display anxiety-like behavior in the light and dark box test and elevated plus maze tests. Interestingly, the mutant mice showed defective response inhibition in the passive avoidance test (PAT) even though their learning ability was intact when measured with the active avoidance test (AAT). These results suggest that promoter IV-dependent BDNF expression plays a critical role in the control of mood-related behaviors. This is the first study that directly addressed the effects of endogenous promoter-driven expression of BDNF in depression-like behavior. © 2010 The Authors. Genes, Brain and Behavior © 2010 Blackwell Publishing Ltd and International Behavioural and Neural Genetics Society.

Stabilizing a graphene platform toward discrete components

NASA Astrophysics Data System (ADS)

Mzali, Sana; Montanaro, Alberto; Xavier, Stéphane; Servet, Bernard; Mazellier, Jean-Paul; Bezencenet, Odile; Legagneux, Pierre; Piquemal-Banci, Maëlis; Galceran, Regina; Dlubak, Bruno; Seneor, Pierre; Martin, Marie-Blandine; Hofmann, Stephan; Robertson, John; Cojocaru, Costel-Sorin; Centeno, Alba; Zurutuza, Amaia

2016-12-01

We report on statistical analysis and consistency of electrical performances of devices based on a large scale passivated graphene platform. More than 500 graphene field effect transistors (GFETs) based on graphene grown by chemical vapor deposition and transferred on 4 in. SiO2/Si substrates were fabricated and tested. We characterized the potential of a two-step encapsulation process including an Al2O3 protection layer to avoid graphene contamination during the lithographic process followed by a final Al2O3 passivation layer subsequent to the GFET fabrication. Devices were investigated for occurrence and reproducibility of conductance minimum related to the Dirac point. While no conductance minimum was observed in unpassivated devices, 75% of the passivated transistors exhibited a clear conductance minimum and low hysteresis. The maximum of the device number distribution corresponds to a residual doping below 5 × 1011 cm-2 (0.023 V/nm). This yield shows that GFETs integrating low-doped graphene and exhibiting small hysteresis in the transfer characteristics can be envisaged for discrete components, with even further potential for low power driven electronics.

Interactions between angiotensin AT1 receptor antagonists and second-generation antiepileptic drugs in the test of maximal electroshock.

PubMed

Łukawski, Krzysztof; Janowska, Agnieszka; Jakubus, Tomasz; Czuczwar, Stanisław J

2014-06-01

The anticonvulsant activity of angiotensin AT1 receptor antagonists, losartan (2-n-butyl-4-chloro-5-hydroxymethyl-1-[(2'(1H-tetrazol-5-yl)-biphenil-4-yl)methyl]imidazole) and telmisartan (49-[(1,49-dimethyl-29-propyl[2,69-bi-1H-benzimidazo]-19-yl)methyl]-[1,19-biphenyl]-2-carboxylic acid), has been reported recently. It is suggested that AT1 receptor antagonists may affect the protective action of antiepileptic drugs. The aim of this study was to determine the influence of losartan and telmisartan on the anticonvulsant activity of some second-generation antiepileptics (lamotrigine - LTG, oxcarbazepine - OXC, and topiramate - TPM). For this purpose, the maximal electroshock seizure (MES) test in mice was used. Additionally, the drug combinations were checked for adverse effects in the passive avoidance and chimney tests. In the MES test, losartan at the doses of 30 and 50 mg/kg, administered intraperitoneally (i.p.), potentiated the protective action of LTG (P < 0.01). This interaction was not accompanied by a significant change of LTG level either in plasma or in the brain. Telmisartan at the dose of 30 mg/kg i.p. enhanced the anticonvulsant action of TPM (P < 0.01). However, this interaction was pharmacokinetic in nature, as telmisartan significantly increased plasma and total brain concentrations of TPM (P < 0.001). The combinations of AT1 receptor antagonists with antiepileptic drugs did not affect retention in the passive avoidance test or motor coordination in the chimney test. The potentiation of the anticonvulsant action of LTG by losartan probably on account of pharmacodynamic interactions, make this combination important for further experimental and clinical studies. The combination of telmisartan and TPM is less beneficial due to pharmacokinetic interactions. © 2013 The Authors Fundamental and Clinical Pharmacology © 2013 Société Française de Pharmacologie et de Thérapeutique.

Child abuse and performance task assessments of executive functions in boys.

PubMed

Mezzacappa, E; Kindlon, D; Earls, F

2001-11-01

We examined executive functions using performance tasks in 126 boys aged 6 to 16 years. who attended public schools and therapeutic schools for children with emotional and behavioral problems. Children were further grouped based on the presence or absence of substantiated abuse histories. Based on their abuse histories and schools of origin, children were classified as Therapeutic, Abused (TA, N = 25). Therapeutic, Nonabused (TN, N = 52), and Public School (PS, N = 48). Controlling IQ and medication status, we compared children in the three groups on teacher ratings of behavior, on experimenter observations of behavior during testing, and on performance tasks challenging the capacities to inhibit an act in progress, and to passively avoid responses associated with adverse consequences. We examined mean group differences in symptoms, behaviors, and task performance, as well as differential age-dependent changes in these dimensions. Independent of abuse history, therapeutic school children demonstrated comparable levels of internalizing and externalizing symptoms, and comparable levels of redirections to task during testing-sessions, that were significantly higher than those of the public school children. Both groups of therapeutic school children also showed comparable overall performance on the capacities to inhibit an act in progress, and to passively avoid responses associated with adverse consequences that were poorer than the performance of children from the public school. Children with histories of substantiated abuse showed diminished improvement with increasing age in the capacity to passively avoid responses associated with adverse consequences when compared not only to the public school children, but also to the children from the therapeutic schools without histories of abuse. Our findings complement reports of behavioral observations of abused children, and reports associating child abuse with altered cognitive development in other areas of competence. They suggest that child abuse may negatively influence the expected developmental progression of competence in certain executive functions. This in turn could have implications for the nature and the persistence of certain forms of psychopathology associated with abuse and poor self-control. Given the cross-sectional nature of our data, however, longitudinal developmental studies of the relations between child abuse and executive functions are needed to elucidate the influence of abuse on the growth and development of such organizing principles of behavioral self-regulation.

The effect of the steroid sulfatase inhibitor (p-O-sulfamoyl)-tetradecanoyl tyramine (DU-14) on learning and memory in rats with selective lesion of septal-hippocampal cholinergic tract.

PubMed

Babalola, P A; Fitz, N F; Gibbs, R B; Flaherty, P T; Li, P-K; Johnson, D A

2012-10-01

Dehydroepiandrosterone sulfate (DHEAS), is an excitatory neurosteroid synthesized within the CNS that modulates brain function. Effects associated with augmented DHEAS include learning and memory enhancement. Inhibitors of the steroid sulfatase enzyme increase brain DHEAS levels and can also facilitate learning and memory. This study investigated the effect of steroid sulfatase inhibition on learning and memory in rats with selective cholinergic lesion of the septo-hippocampal tract using passive avoidance and delayed matching to position T-maze (DMP) paradigms. The selective cholinergic immunotoxin 192 IgG-saporin (SAP) was infused into the medial septum of animals and then tested using a step-through passive avoidance paradigm or DMP paradigm. Peripheral administration of the steroid sulfatase inhibitor, DU-14, increased step-through latency following footshock in rats with SAP lesion compared to both vehicle treated control and lesioned animals (p<0.05). However, in the DMP task, steroid sulfatase inhibition impaired acquisition in lesioned rats while having no effect on intact animals. These results suggest that steroid sulfatase inhibition facilitates memory associated with contextual fear, but impairs acquisition of spatial memory tasks in rats with selective lesion of the septo-hippocampal tract. Copyright © 2012 Elsevier Inc. All rights reserved.

Comparison of pro-amnesic efficacy of scopolamine, biperiden, and phencyclidine by using passive avoidance task in CD-1 mice.

PubMed

Malikowska, Natalia; Sałat, Kinga; Podkowa, Adrian

2017-07-01

Memory disorders accompany numerous diseases and therapies, and this is becoming a growing medical issue worldwide. Currently, various animal models of memory impairments are available; however, many of them require high financial outlay and/or are time-consuming. A simple way to achieve an efficient behavioral model of cognitive disorders is to inject defined drug that has pro-amnesic properties. Since the involvement of cholinergic and glutamatergic neurotransmission in cognition is well established, the utilization of a nonselective muscarinic receptor antagonist, scopolamine (SCOP), a selective M1 muscarinic receptor antagonist, biperiden (BIP), and a non-competitive N-methyl-d-aspartate (NMDA) receptor antagonist, phencyclidine (PCP) seems to be reliable tools to induce amnesia. As the determination of their effective doses remains vague and the active doses vary significantly in laboratory settings and in mouse species being tested, the aim of this study was to compare these three models of amnesia in CD-1 mice. Male Swiss Albino mice were used in passive avoidance (PA) test. All the compounds were administered intraperitoneally (ip) at doses 1mg/kg, 5mg/kg, and 10mg/kg (SCOP and BIP), and 1mg/kg, 3mg/kg, and 6mg/kg (PCP). In the retention trial of the PA task, SCOP and PCP led to the reduction of step-through latency at all the tested doses as compared to control, but BIP was effective only at the dose of 10mg/kg. This study revealed the effectiveness of SCOP, PCP, and BIP as tools to induce amnesia, with the PCP model being the most efficacious and SCOP being the only model that demonstrates a clear dose-response relationship. Copyright © 2017. Published by Elsevier Inc.

Edaravone attenuates intracerebroventricular streptozotocin-induced cognitive impairment in rats.

PubMed

Reeta, K H; Singh, Devendra; Gupta, Yogendra K

2017-04-01

Alzheimer's disease is a major cause of dementia worldwide. Edaravone, a potent free radical scavenger, is reported to be neuroprotective. The present study was designed to investigate the effect of chronic edaravone administration on intracerebroventricular-streptozotocin (ICV-STZ) induced cognitive impairment in male Wistar rats. Cognitive impairment was developed by single ICV-STZ (3 mg/kg) injection bilaterally on day 1. Edaravone (1, 3 and 10 mg/kg, orally, once daily) was administered for 28 days. Morris water maze and passive avoidance tests were used to assess cognitive functions at baseline and on days 14 and 28. ICV-STZ caused cognitive impairment as evidenced by increased escape latency and decreased time spent in target quadrant in the Morris water maze test and reduced retention latency in the passive avoidance test. STZ caused increase in oxidative stress, cholinesterases, inflammatory cytokines and protein expression of ROCK-II and decrease in protein expression of ChAT. Edaravone ameliorated the STZ-induced cognitive impairment. STZ-induced increase in oxidative stress and increased levels of pro-inflammatory cytokines (TNF-α, IL-1β) were mitigated by edaravone. Edaravone also prevented STZ-induced increased protein expression of ROCK-II. Moreover, edaravone significantly prevented STZ-induced increased activity of cholinesterases in the cortex and hippocampus. The decreased expression of ChAT caused by STZ was brought towards normal by edaravone in the hippocampus. The results thus show that edaravone is protective against STZ-induced cognitive impairment, oxidative stress, cholinergic dysfunction and altered protein expressions. This study thus suggests the potential of edaravone as an adjuvant in the treatment of Alzheimer's disease. © 2017 Federation of European Neuroscience Societies and John Wiley & Sons Ltd.

Z-Guggulsterone Improves the Scopolamine-Induced Memory Impairments Through Enhancement of the BDNF Signal in C57BL/6J Mice.

PubMed

Chen, Zhuo; Huang, Chao; Ding, Wenbin

2016-12-01

Memory impairment is a common symptom in patients with neurodegenerative disorders, and its suppression could be beneficial to improve the quality of life of those patients. Z-guggulsterone, a compound extracted from the resin of plant Commiphora whighitii, exhibits numerous pharmacological effects in clinical practice, such as treatment of inflammation, arthritis, obesity and lipid metabolism disorders. However, the role and possible mechanism of Z-guggulsterone on brain-associated memory impairments are largely unknown. This issue was addressed in the present study in a memory impairment model induced by scopolamine, a muscarinic acetylcholine receptor antagonist, using the passive avoidance, Y-maze and Morris water maze tests. Results showed that scopolamine significantly decreased the step-through latency and spontaneous alternation of C57BL/6J mice in passive avoidance and Y-maze test, whereas increased the mean escape latency and decreased the swimming time in target quadrant in Morris water maze test. Pretreatment of mice with Z-guggulsterone at doses of 30 and 60 mg/kg effectively reversed the scopolamine-induced memory impairments. Mechanistic studies revealed that Z-guggulsterone pretreatment reversed the scopolamine-induced increase in acetylcholinesterase (AchE) activity, as well as decreases in brain-derived neurotrophic factor (BDNF) protein expression and cAMP response element-binding protein (CREB), extracellular regulated kinase 1/2 (ERK1/2) and protein kinase B (Akt) phosphorylation levels in the hippocampus and cortex. Inhibition of the BDNF signal, however, blocked the memory-enhancing effect of Z-guggulsterone. Therefore, these findings demonstrate that Z-guggulsterone attenuates the scopolamine-induced memory impairments mainly through activation of the CREB-BDNF signaling pathway, thereby exhibiting memory-improving effects.

Evaluation of acute tacrine treatment on passive-avoidance response, open-field behavior, and toxicity in 17- and 30-day-old mice.

PubMed

Pan, S Y; Han, Y F; Yu, Z L; Yang, R; Dong, H; Ko, K M

2006-09-01

The potential of tacrine in altering cognitive/behavioral function as well as in causing toxicity was evaluated in mice of 17 and 30 days of age. Cognitive and behavioral studies were performed using a step-through passive avoidance task and a habituation open-field test with a 24-h retention interval. Tacrine was subcutaneously injected (1.25-80 micro mol/kg) 30 min prior to the first session of both tests. During the training session in step-through task, tacrine treatment dose-dependently decreased the number of footshocks, with IC(50) values being 7.8 and 23.3 micro mol/kg in 17- and 30-day-old mice, respectively. Treatment with tacrine at a low dose (5 micro mol/kg) significantly prolonged the retention latency in 17-day-old mice only, but it shortened the retention latency at high doses of 20 and 40 micro mol/kg in 17- and 30-day-old, respectively. During the acquisition session in the open-field test, tacrine treatment dose-dependently decreased the locomotor activity in 17- and 30-day-old mice, with IC(50) values being 15.1 and 24.7 micro mol/kg, respectively. High doses of tacrine invariably increased the locomotor activity during the recall session. Tacrine treatment at a dose of 40 micro mol/kg caused a significant increase in serum alanine aminotransferase activity in 17- and 30-day-old mice at 6 h post-dosing, with the extent of stimulation in 30-day-old mice being more prominent. In conclusion, tacrine was more potent in enhancing/disrupting the cognitive function, inhibiting locomotor activity as well as in causing hepatotoxicity in 17-day-old than in 30-day-old mice.

COBALT CoOperative Blending of Autonomous Landing Technology

NASA Technical Reports Server (NTRS)

Carson, John M. III; Restrepo, Carolina I.; Robertson, Edward A.; Seubert, Carl R.; Amzajerdian, Farzin

2016-01-01

COBALT is a terrestrial test platform for development and maturation of GN&C (Guidance, Navigation and Control) technologies for PL&HA (Precision Landing and Hazard Avoidance). The project is developing a third generation, Langley Navigation Doppler Lidar (NDL) for ultra-precise velocity and range measurements, which will be integrated and tested with the JPL Lander Vision System (LVS) for Terrain Relative Navigation (TRN) position estimates. These technologies together provide navigation that enables controlled precision landing. The COBALT hardware will be integrated in 2017 into the GN&C subsystem of the Xodiac rocket-propulsive Vertical Test Bed (VTB) developed by Masten Space Systems (MSS), and two terrestrial flight campaigns will be conducted: one open-loop (i.e., passive) and one closed-loop (i.e., active).

[Interaction of immobilization stress and food-getting learning].

PubMed

Levshina, I P; Stashkevich, I S; Shuĭkin, N N

2009-01-01

The behavioral effects of emotional negative stress (immobilization) were studied in Wistar rats intact and those that had previous positive emotion experience. The food-getting learning has been chosen as positive emotion experience. Animals were trained in food pellet-reaching task by their preferred paw. It was shown that immobilization of intact rats leads to suppression of motor activity and increasing the duration of grooming. These effects indicate enhancement of passive-avoidance reactions. It was also shown that motor learning in group of rats with food reinforcement before immobilisation significantly reduces appearance of passive-avoidance reactions. It was found that immobilization stress does not inverse the initial direction of limb preference in majority of rats.

Transformational leadership in primary care: Clinicians' patterned approaches to care predict patient satisfaction and health expectations.

PubMed

Huynh, Ho Phi; Sweeny, Kate; Miller, Tricia

2018-04-01

Clinicians face the complex challenge of motivating their patients to achieve optimal health while also ensuring their satisfaction. Inspired by transformational leadership theory, we proposed that clinicians' motivational behaviors can be organized into three patient care styles (transformational, transactional, and passive-avoidant) and that these styles differentially predict patient health outcomes. In two studies using patient-reported data and observer ratings, we found that transformational patient care style positively predicted patients' satisfaction and health expectations above and beyond transactional and passive-avoidant patient care style. These findings provide initial support for the patient care style approach and suggest novel directions for the study of clinicians' motivational behaviors.

Effects of (-)-S-2,8-dimethyl-3-methylene-1-oxa-8-azaspiro[4,5]decane L-tartrate monohydrate (YM796), a novel muscarinic agonist, on disturbance of passive avoidance learning behavior in drug-treated and senescence-accelerated mice.

PubMed

Suzuki, M; Yamaguchi, T; Ozawa, Y; Ohyama, M; Yamamoto, M

1995-11-01

Effects of YM796 (-)-S-2,8-dimethyl-3-methylene-1-oxa-8-azaspiro[4,5]decane L-tartrate monohydrate; a novel muscarinic agonist, were observed on disturbance of passive avoidance learning behavior in drug- (protein synthesis inhibitor and anticholinergic drugs) treated and senescence-accelerated mice in comparison with those of a muscarinic agonist (AF102B) and acetylcholinesterase inhibitors (E2020 (1-benzyl-4-[(5,6-dimethoxy-1-indanone-2-yl) methyl] piperidene hydrochloride), NIK247 [9-amino-2,3,5,6,7,8-hexahydro-1H-cyclopenta(b)-quinoline monohydrate hydrochloride], THA (9-amino-1,2,3,4-tetrahydroacridine) and physostigmine). All tested drugs administered before training significantly prolonged the shortened latency of step-through induced by the protein synthesis inhibitor cycloheximide (150 mg/kg s.c.). This shortened latency was also significantly prolonged when YM796 was administered immediately after training, but not when administered before the test trial. The ameliorating effect of YM796 on the impairment in learning behavior by cycloheximide was significantly suppressed by pirenzepine (0.1 micrograms/mouse i.c.v.). When administered before training, all test drugs prolonged the shortened latency of step-through induced by treatment with the anticholinergic drugs [scopolamine (1 mg/kg s.c.) and hemicholinium-3 (0.3 microgram/mouse i.c.v.)], suggesting that they ameliorated the impairment of learning behavior. This shortened latency in scopolamine-treated mice was also significantly prolonged by YM796, AF102B, E2020, NIK247 and physostigmine when administered immediately after training, but not when administered before the test trial. The pharmacological actions of YM796 administered immediately after training and before the test trial in hemicholinium-3-treated mice were similar to those in scopolamine-treated mice.(ABSTRACT TRUNCATED AT 250 WORDS)

Identifying the Factors That Facilitate or Hinder Advance Planning by Persons With Dementia

PubMed Central

Hirschman, Karen B.; Kapo, Jennifer M.; Karlawish, Jason H. T.

2009-01-01

We performed semistructured interviews with 30 family members of patients with advanced dementia to identify the factors that facilitate or hinder advance planning by persons with dementia. All interviews were analyzed using qualitative data analysis techniques. The majority (77%) of family members reported that their relative had some form of written advance directive, and at least half reported previous discussions about health care preferences (57%), living situation or placement issues (50%), and finances or estate planning (60%) with the patient. Family members reported some themes that prompted planning and others that were barriers to planning. Events that most often triggered planning were medical, living situation, or financial issues associated with a friend or family member of the patient (57%). Barriers to planning included both passive and active avoidance. The most common form of passive avoidance was not realizing the importance of planning until it was too late to have the discussion (63%). The most common form of active avoidance was avoiding the discussion (53%). These data suggest potentially remediable strategies to address barriers to advance planning discussions. PMID:18580595

Asymmetric band offsets in silicon heterojunction solar cells: Impact on device performance

DOE Office of Scientific and Technical Information (OSTI.GOV)

Seif, Johannes Peter; Menda, Deneb; Descoeudres, Antoine

Here, amorphous/crystalline silicon interfaces feature considerably larger valence than conduction band offsets. In this article, we analyze the impact of such band offset asymmetry on the performance of silicon heterojunction solar cells. To this end, we use silicon suboxides as passivation layers -- inserted between substrate and (front or rear) contacts -- since such layers enable intentionally exacerbated band-offset asymmetry. Investigating all topologically possible passivation layer permutations and focussing on light and dark current-voltage characteristics, we confirm that to avoid fill factor losses, wider-bandgap silicon oxide films (of at least several nanometer thin) should be avoided in hole-collecting contacts. Asmore » a consequence, device implementation of such films as window layers -- without degraded carrier collection -- demands electron collection at the front and hole collection at the rear. Furthermore, at elevated operating temperatures, once possible carrier transport barriers are overcome by thermionic (field) emission, the device performance is mainly dictated by the passivation of its surfaces. In this context, compared to the standard amorphous silicon layers, the wide-bandgap oxide layers applied here passivate remarkably better at these temperatures, which may represent an additional benefit under practical operation conditions.« less

Asymmetric band offsets in silicon heterojunction solar cells: Impact on device performance

DOE PAGES

Seif, Johannes Peter; Menda, Deneb; Descoeudres, Antoine; ...

2016-08-01

Here, amorphous/crystalline silicon interfaces feature considerably larger valence than conduction band offsets. In this article, we analyze the impact of such band offset asymmetry on the performance of silicon heterojunction solar cells. To this end, we use silicon suboxides as passivation layers -- inserted between substrate and (front or rear) contacts -- since such layers enable intentionally exacerbated band-offset asymmetry. Investigating all topologically possible passivation layer permutations and focussing on light and dark current-voltage characteristics, we confirm that to avoid fill factor losses, wider-bandgap silicon oxide films (of at least several nanometer thin) should be avoided in hole-collecting contacts. Asmore » a consequence, device implementation of such films as window layers -- without degraded carrier collection -- demands electron collection at the front and hole collection at the rear. Furthermore, at elevated operating temperatures, once possible carrier transport barriers are overcome by thermionic (field) emission, the device performance is mainly dictated by the passivation of its surfaces. In this context, compared to the standard amorphous silicon layers, the wide-bandgap oxide layers applied here passivate remarkably better at these temperatures, which may represent an additional benefit under practical operation conditions.« less

Asymmetric band offsets in silicon heterojunction solar cells: Impact on device performance

DOE Office of Scientific and Technical Information (OSTI.GOV)

Seif, Johannes Peter, E-mail: johannes.seif@alumni.epfl.ch; Ballif, Christophe; De Wolf, Stefaan

Amorphous/crystalline silicon interfaces feature considerably larger valence than conduction band offsets. In this article, we analyze the impact of such band offset asymmetry on the performance of silicon heterojunction solar cells. To this end, we use silicon suboxides as passivation layers—inserted between substrate and (front or rear) contacts—since such layers enable intentionally exacerbated band-offset asymmetry. Investigating all topologically possible passivation layer permutations and focussing on light and dark current-voltage characteristics, we confirm that to avoid fill factor losses, wider-bandgap silicon oxide films (of at least several nanometer thin) should be avoided in hole-collecting contacts. As a consequence, device implementation ofmore » such films as window layers—without degraded carrier collection—demands electron collection at the front and hole collection at the rear. Furthermore, at elevated operating temperatures, once possible carrier transport barriers are overcome by thermionic (field) emission, the device performance is mainly dictated by the passivation of its surfaces. In this context, compared to the standard amorphous silicon layers, the wide-bandgap oxide layers applied here passivate remarkably better at these temperatures, which may represent an additional benefit under practical operation conditions.« less

Passive imaging based multi-cue hazard detection spacecraft safe landing

NASA Technical Reports Server (NTRS)

Huertas, Andres; Cheng, Yang; Madison, Richard

2006-01-01

Accurate assessment of potentially damaging ground hazards during the spacecraft EDL (Entry, Descent and Landing) phase is crucial to insure a high probability of safe landing. A lander that encounters a large rock, falls off a cliff, or tips over on a steep slope can sustain mission ending damage. Guided entry is expected to shrink landing ellipses from 100-300 km to -10 km radius for the second generation landers as early as 2009. Regardless of size and location, however, landing ellipses will almost always contain hazards such as craters, discontinuities, steep slopes, and large rocks. It is estimated that an MSL (Mars Science Laboratory)-sized lander should detect and avoid 16- 150m diameter craters, vertical drops similar to the edges of 16m or 3.75m diameter crater, for high and low altitude HAD (Hazard Detection and Avoidance) respectively. It should also be able to detect slopes 20' or steeper, and rocks 0.75m or taller. In this paper we will present a passive imaging based, multi-cue hazard detection and avoidance (HDA) system suitable for Martian and other lander missions. This is the first passively imaged HDA system that seamlessly integrates multiple algorithm-crater detection, slope estimation, rock detection and texture analysis, and multicues- crater morphology, rock distribution, to detect these hazards in real time.

Environmental assessment and management of metal-rich wastes generated in acid mine drainage passive remediation systems.

PubMed

Macías, Francisco; Caraballo, Manuel A; Nieto, José Miguel

2012-08-30

As acid mine drainage (AMD) remediation is increasingly faced by governments and mining industries worldwide, the generation of metal-rich solid residues from the treatments plants is concomitantly raising. A proper environmental management of these metal-rich wastes requires a detailed characterization of the metal mobility as well as an assessment of this new residues stability. The European standard leaching test EN 12457-2, the US EPA TCLP test and the BCR sequential extraction procedure were selected to address the environmental assessment of dispersed alkaline substrate (DAS) residues generated in AMD passive treatment systems. Significant discrepancies were observed in the hazardousness classification of the residues according to the TCLP or EN 12457-2 test. Furthermore, the absence of some important metals (like Fe or Al) in the regulatory limits employed in both leaching tests severely restricts their applicability for metal-rich wastes. The results obtained in the BCR sequential extraction suggest an important influence of the landfill environmental conditions on the metals released from the wastes. To ensure a complete stability of the pollutants in the studied DAS-wastes the contact with water or any other leaching solutions must be avoided and a dry environment needs to be provided in the landfill disposal selected. Copyright © 2012 Elsevier B.V. All rights reserved.

Choice of conflict resolution strategy is linked to sociability in dog puppies.

PubMed

Riemer, Stefanie; Müller, Corsin; Virányi, Zsófia; Huber, Ludwig; Range, Friederike

2013-12-01

Measures that are likely to increase sociability in dog puppies, such as appropriate socialisation, are considered important in preventing future fear or aggression related problems. However, the interplay between sociability and conflict behaviour has rarely been investigated. Moreover, while many studies have addressed aggression in domestic dogs, alternative, non-aggressive conflict resolution strategies have received less scientific attention. Here we tested 134 Border collie puppies, aged 40-50 days, in a personality test which included friendly interactions with an unfamiliar person, exposure to a novel object, and three brief restraint tests. Considering the latter to be mild 'conflict' situations, we analysed whether the puppies' behaviour in the restraint tests was related to their sociability or to their boldness towards the novel object. Strategies employed by the puppies during restraint tests included trying to interact socially with the experimenter, remaining passive, and attempting to move away. In line with findings from humans and goats, puppies scoring high on sociability were more likely to adopt an interactive conflict resolution strategy, while those with low sociability scores tended to react passively. In contrast, avoidance behaviours were unrelated to sociability, possibly reflecting inconsistency in the flight strategy in dogs. Boldness towards a novel object was not related to sociability or to puppies' reactions in restraint tests. This is one of the first studies to demonstrate a link between sociability and conflict resolution strategies in non-human animals.

Nootropic Effects of Filipendula Vulgaris Moench Water Extract Fractions.

PubMed

Shilova, I V; Suslov, N I; Amelchenko, V P

2015-07-01

Nootropic activity of water extract fractions from aerial parts of Filipendula vulgaris Moench was demonstrated on the models of hermetic volume hypoxia, conditioned passive avoidance response, open field test, and forced swimming with a load. The fractions stimulated hypoxic resistance, normalized orientation and exploratory behavior, improved conditioned response reproduction during testing after hypoxic injury, and increased exercise tolerance. Fractionation of the extract led to dissociation of the effect components, which suggests that individual constituents have specific characteristics. Ethylacetate fraction exhibited most pronounced nootropic activity and was superior to plant extract by some characteristics. The detected effects seemed to be caused by modulation of the hippocampus activity the under the effects of phenol and triterpene compounds.

Avoidance of Phycomyces in a controlled environment.

PubMed Central

Meyer, P W; Matus, I J; Berg, H C

1987-01-01

The sporangiophore of the fungus Phycomyces bends away from nearby objects without ever touching them. It has been thought that these objects act as aerodynamic obstacles that damp random winds, thereby generating asymmetric distributions of a growth-promoting gas emitted by the growth zone. In the interest of testing this hypothesis, we studied avoidance in an environmental chamber in which convection was suppressed by a shallow thermal gradient. We also controlled pressure, temperature, and relative humidity of the air, electrostatic charge, and ambient light. A protocol was established that yielded avoidance rates constant from sporangiophore to sporangiophore to within +/- 10%. We found that avoidance occurred at normal rates in the complete absence of random winds. The rates were smaller at 100% than at lower values of relative humidity, but not by much. Remarkably, at a distance as great as 0.5 mm, avoidance from a 30-micron diam glass fiber (aligned parallel to the sporangiophore) was about the same as that from a planar glass sheet. However, the rate for the fiber fell more rapidly with distance. The rate for the sheet remained nearly constant out to approximately 4 mm. We conclude that avoidance depends either on adsorption by the barrier of a growth-inhibiting substance or emission by the barrier of a growth-promoting substance; it cannot occur by passive reflection. Models that can explain these effects are analyzed in the Appendix. PMID:3567313

Effect of Calendula officinalis hydroalcoholic extract on passive avoidance learning and memory in streptozotocin-induced diabetic rats

PubMed Central

Moradkhani, Shirin; Salehi, Iraj; Abdolmaleki, Somayeh; Komaki, Alireza

2015-01-01

Background: Medicinal plants, owing to their different mechanisms such as antioxidants effects, may improve learning and memory impairments in diabetic rats. Calendula officinalis (CO), has a significant antioxidant activity. Aims: To examine the effect of hydroalcoholic extract of CO on passive avoidance learning (PAL) and memory in streptozotocin (STZ)-induced diabetic male rats. Settings and Design: A total of 32 adult male Wistar rats were randomly allocated to four groups: Control, diabetic, control + extract of CO and diabetic control + extract of CO groups with free access to regular rat diet. Subjects and Methods: Diabetes in diabetic rats was induced by single intraperitoneal injection of 60 mg/kg STZ. After confirmation of diabetes, oral administration of 300 mg/kg CO extract to extract-treated groups have been done. PAL was tested 8 weeks after onset of treatment, and blood glucose and body weight were measured in all groups at the beginning and end of the experiment. Statistical Analysis Used: The statistical analysis of data was performed by ANOVA followed by least significant difference post-hoc analysis. Results: Diabetes decreased learning and memory. Effect of CO extract in retention test (after 24 and 48 h) has been shown a significant decrease in step-through latency and increase in time spent in the dark compartment part. Also the extract partially improved hyperglycemia and reduced body weight. Conclusion: Taken together, CO extract can improve PAL and memory impairments in STZ-diabetic rats. This improvement may be due to its antioxidant, anticholinergic activities or its power to reduce hyperglycemia. PMID:26120230

Pharmacological validation of in-silico guided novel nootropic potential of Achyranthes aspera L.

PubMed

Gawande, Dinesh Yugraj; Goel, Rajesh Kumar

2015-12-04

Achyranthes aspera (A. aspera) has been used as a brain tonic in folk medicine. Although, ethnic use of medicinal plant has been basis for drug discovery from medicinal plants, but the available in-silico tools can be useful to find novel pharmacological uses of medicinal plants beyond their ethnic use. To validate in-silico prediction for novel nootropic effect of A. aspera by employing battery of tests in mice. Phytoconstituents of A. aspera reported in Dictionary of Natural Product were subjected to in-silico prediction using PASS and Pharmaexpert. The nootropic activity predicted for A. aspera was assessed using radial arm maze, passive shock avoidance and novel object recognition tests in mice. After behavioral evaluation animals were decapitated and their brains were collected and stored for estimation of glutamate levels and acetylcholinesterase activity. In-silico activity spectrum for majority of A. aspera phytoconstituents exhibited excellent prediction score for nootropic activity of this plant. A. aspera extract treatment significantly improved the learning and memory as evident by decreased working memory errors, reference memory errors and latency time in radial arm maze, step through latency in passive shock avoidance and increased recognition index in novel object recognition were observed, moreover significantly enhanced glutamate levels and reduced acetylcholinesterase activity in hippocampus and cortex were observed as compared to the saline treated group. In-silico and in-vivo results suggest that A. aspera plant may improve the learning and memory by modulating the brain glutamatergic and cholinergic neurotransmission. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

Neuropathological Changes in Brain Cortex and Hippocampus in a Rat Model of Alzheimer’s Disease

PubMed Central

Nobakht, Maliheh; Hoseini, Seyed Mohammad; Mortazavi, Pejman; Sohrabi, Iraj; Esmailzade, Banafshe; Roosh, Nahid Rahbar; Omidzahir, Shila

2011-01-01

Background: Alzheimer’s disease (AD) is a neurodegenerative disorder with progressive loss of cognitive abilities and memory loss. The aim of this study was to compare neuropathological changes in hippocampus and brain cortex in a rat model of AD. Methods: Adult male Albino Wistar rats (weighing 250-300 g) were used for behavioral and histopathological studies. The rats were randomly assigned to three groups: control, sham and β-amyloid (Aβ) injection. For behavioral analysis, Y-maze and shuttle box were used, respectively at 14 and 16 days post-lesion. For histological studies, Nissl, modified Bielschowsky and modified Congo red staining were performed. The lesion was induced by injection of 4 µL of Aβ (1-40) into the hippocampal fissure. Results: In the present study, Aβ (1-40) injection into hippocampus could decrease the behavioral indexes and the number of CA1 neurons in hippocampus. Aβ injection CA1 caused Aβ deposition in the hippocampus and less than in cortex. We observed the loss of neurons in the hippocampus and cerebral cortex and certain subcortical regions. Y-maze test and single-trial passive avoidance test showed reduced memory retention in AD group. Conclusion: We found a significant decreased acquisition of passive avoidance and alternation behavior responses in AD group compared to control and sham group (P<0.0001). Compacted amyloid cores were present in the cerebral cortex, hippocampus and white matter, whereas, scattered amyloid cores were seen in cortex and hippocampus of AD group. Also, reduced neuronal density was indicated in AD group. PMID:21725500

Molecular Monolayers for Electrical Passivation and Functionalization of Silicon-Based Solar Energy Devices.

PubMed

Veerbeek, Janneke; Firet, Nienke J; Vijselaar, Wouter; Elbersen, Rick; Gardeniers, Han; Huskens, Jurriaan

2017-01-11

Silicon-based solar fuel devices require passivation for optimal performance yet at the same time need functionalization with (photo)catalysts for efficient solar fuel production. Here, we use molecular monolayers to enable electrical passivation and simultaneous functionalization of silicon-based solar cells. Organic monolayers were coupled to silicon surfaces by hydrosilylation in order to avoid an insulating silicon oxide layer at the surface. Monolayers of 1-tetradecyne were shown to passivate silicon micropillar-based solar cells with radial junctions, by which the efficiency increased from 8.7% to 9.9% for n + /p junctions and from 7.8% to 8.8% for p + /n junctions. This electrical passivation of the surface, most likely by removal of dangling bonds, is reflected in a higher shunt resistance in the J-V measurements. Monolayers of 1,8-nonadiyne were still reactive for click chemistry with a model catalyst, thus enabling simultaneous passivation and future catalyst coupling.

Passive Collision Avoidance System for UAS

DTIC Science & Technology

2008-09-01

feasibility of using SWAP efficient LWIR microbolometers as outlined in the Priest report circa 1998 as a solution to the collision avoidance problems for UASs...81 7.3 LWIR Multispectral Sensor ..........................................................................................84 7.4 LWIR ... LWIR image of the Ultralight. Muffler runs at approximately 1200 F. ......................32 Figure 36: 3D model of LVDS circuit board with L-3

Chronic treatment with the new anticonvulsant drug lacosamide impairs learning and memory processes in rats: A possible role of BDNF/TrkB ligand receptor system.

PubMed

Shishmanova-Doseva, Michaela; Peychev, Lyudmil; Koeva, Yvetta; Terzieva, Dora; Georgieva, Katerina; Peychev, Zhivko

2018-06-01

Cognitive impairment is considered a frequent side effect in the drug treatment of epilepsy. The objective of the present study was to investigate the effects of lacosamide (LCM) on learning and memory processes in rats, on the serum level of brain-derived neurotrophic factor (BDNF) and BDNF/TrkB ligand receptor system expression in the hippocampal formation. Male Wistar rats underwent long-term treatment with three different doses of lacosamide - 3 mg/kg (LCM 3), 10 mg/kg (LCM 10) and 30 mg/kg (LCM 30). All rats were subjected to one active and one passive avoidance tests. The BDNF/TrkB immunohistochemical expression in the hippocampus was measured and serum BDNF was determined. The LCM-treated rats made fewer avoidance responses than controls during acquisition training and in the memory retention test. The number of escapes in the LCM 10 and LCM 30 groups decreased throughout the test, while the rats in the LCM 3 group showed fewer escapes only in the memory test in the active avoidance task. In the step-down test, the latency time of the LCM-30 treated rats was reduced as compared with the controls during the learning session and the short- and long-term memory retention tests. Lacosamide induced a dose-dependent reduction of the hippocampal expression of BDNF and its receptor TrkB. We found no significant difference between BDNF serum levels in the test animals and controls. The results of the study suggest that LCM suppresses the learning and memory processes in rats, with the inhibition of hippocampal BDNF/TrkB ligand receptor system being one of the possible mechanisms causing this effect. Copyright © 2018 Elsevier Inc. All rights reserved.

Betaine prevents homocysteine-induced memory impairment via matrix metalloproteinase-9 in the frontal cortex.

PubMed

Kunisawa, K; Nakashima, N; Nagao, M; Nomura, T; Kinoshita, S; Hiramatsu, M

2015-10-01

Betaine plays important roles that include acting as a methyl donor and converting homocysteine (Hcy) to methionine. Elevated plasma Hcy levels are known as hyperhomocysteinemia (HHcy) and contribute to impairments of learning and memory. Although it is commonly known that betaine plays an important role in Hcy metabolism, the effects of betaine on Hcy-induced memory impairment have not been investigated. Previously, we demonstrated the beneficial effects of betaine on acute stress and lipopolysaccharide-induced memory impairment. In the present study, we investigated whether betaine ameliorates Hcy-induced memory impairment and the underlying mechanisms of this putative effect. Mice were treated with Hcy (0.162mg/kg, s.c.) twice a day for nine days, and betaine (25mg/kg, s.c.) was administered 30min before the Hcy injections. The memory functions were evaluated using a spontaneous alternation performance test (Y-maze) at seven days and a step-down type passive avoidance test (SD) at nine and ten days after Hcy injection. We found that betaine suppressed the memory impairment induced by repeated Hcy injections. However, the blood concentrations of Hcy were significantly increased in the Hcy-treated mice immediately after the passive avoidance test, and betaine did not prevent this increase. Furthermore, Hcy induces redox stress in part by activating matrix metalloproteinase-9 (MMP-9), which leads to BBB dysfunction. Therefore, we tested whether betaine affected MMP-9 activity. Interestingly, treatment with betaine significantly inhibited Hcy-induced MMP-9 activity in the frontal cortex but not in the hippocampus after acute Hcy injection. These results suggest that the changes in MMP-9 activity after betaine treatment might have been partially responsible for the amelioration of the memory deficits and that MMP-9 might be a candidate therapeutic target for HHcy. Copyright © 2015 Elsevier B.V. All rights reserved.

Deer Bone Extract Prevents Against Scopolamine-Induced Memory Impairment in Mice

PubMed Central

Du, Chun Nan; Min, A Young; Kim, Hyun Jeong; Shin, Suk Kyung; Yu, Ha Ni; Sohn, Eun Jeong; Ahn, Chang-Won; Jung, Sung Ug; Park, Soo-Hyun

2015-01-01

Abstract Deer bone has been used as a health-enhancing food as well as an antiaging agent in traditional Oriental medicine. Recently, the water extract of deer bone (DBE) showed a neuroprotective action against glutamate or Aβ1–42-induced cell death of mouse hippocampal cells by exerting antioxidant activity through the suppression of MAP kinases. The present study is to examine whether DBE improves memory impairment induced by scopolamine. DBE (50, 100 or 200 mg/kg) was administered orally to mice for 14 days, and then scopolamine (2 mg/kg, i.p.) was administered together with DBE for another 7 days. Memory performance was evaluated in the Morris water maze (MWM) test and passive avoidance test. Also, brain acetylcholinesterase (AChE) and choline acetyltransferase (ChAT) activity, biomarkers of oxidative stress and the loss of neuronal cells in the hippocampus, was evaluated by histological examinations. Administration of DBE significantly restored memory impairments induced by scopolamine in the MWM test (escape latency and number of crossing platform area), and in the passive avoidance test. Treatment with DBE inhibited the AChE activity and increased the ChAT activity in the brain of memory-impaired mice induced by scopolamine. Additionally, the administration of DBE significantly prevented the increase of lipid peroxidation and the decrease of glutathione level in the brain of mice treated with scopolamine. Also, the DBE treatment restored the activities of antioxidant enzymes such as superoxide dismutase, glutathione peroxidase, and glutathione reductase to control the level. Furthermore, scopolamine-induced oxidative damage of neurons in hippocampal CA1 and CA3 regions were prevented by DBE treatment. It is suggested that DBE may be useful for memory improvement through the regulation of cholinergic marker enzyme activities and the suppression of oxidative damage of neurons in the brain of mice treated with scopolamine. PMID:25546299

Influence of ring size on the cognition-enhancing activity of DM235 and MN19, two potent nootropic drugs.

PubMed

Guandalini, L; Martini, E; Di Cesare Mannelli, L; Dei, S; Manetti, D; Scapecchi, S; Teodori, E; Ghelardini, C; Romanelli, M N

2012-03-01

A series of analogs of DM235 and MN19, characterized by rings with different size, have been prepared and evaluated for their nootropic activity in the mouse passive-avoidance test. It was found that the optimal ring size for the analogs of DM235, showing endocyclic both amidic groups, is 6 or 7 atoms. For the compounds structurally related to MN19, carrying an exocyclic amide group, the piperidine ring is the moiety which gives the most interesting compounds. Copyright © 2012 Elsevier Ltd. All rights reserved.

Deficient behavioral inhibition and anomalous selective attention in a community sample of adolescents with psychopathic traits and low-anxiety traits.

PubMed

Vitale, Jennifer E; Newman, Joseph P; Bates, John E; Goodnight, Jackson; Dodge, Kenneth A; Pettit, Gregory S

2005-08-01

Socialization is the important process by which individuals learn and then effectively apply the rules of appropriate societal behavior. Response modulation is a psychobiological process theorized to aid in socialization by allowing individuals to utilize contextual information to modify ongoing behavior appropriately. Using Hare's (1991) Psychopathy Checklist and the Welsh (1956) anxiety scale, researchers have identified a relatively specific form of a response modulation deficit in low-anxious, Caucasian psychopaths. Preliminary evidence suggests that the Antisocial Process Screening Device (APSD; Frick & Hare, 2001) may be used to identify children with a similar vulnerability. Using a representative community sample of 308 16-year-olds from the Child Development Project (Dodge, Bates, & Pettit, 1990), we tested and corroborated the hypotheses that participants with relatively low anxiety and high APSD scores would display poorer passive avoidance learning and less interference on a spatially separated, picture-word Stroop task than controls. Consistent with hypotheses, the expected group differences in picture-word Stroop interference were found with male and female participants, whereas predicted differences in passive avoidance were specific to male participants. To the extent that response modulation deficits contributing to poor socialization among psychopathic adult offenders also characterize a subgroup of adolescents with mild conduct problems, clarification of the developmental processes that moderate the expression of this vulnerability could inform early interventions.

The n-butanolic extract of Opuntia ficus-indica var. saboten enhances long-term memory in the passive avoidance task in mice.

PubMed

Kim, Jong Min; Kim, Dong Hyun; Park, Se Jin; Park, Dong Hyun; Jung, Seo Yun; Kim, Hyoung Ja; Lee, Yong Sup; Jin, Changbae; Ryu, Jong Hoon

2010-08-16

Opuntia ficus-indica var. saboten Makino (Cactaceae) is used to treat burns, edema, dyspepsia, and asthma in traditional medicine. The present study investigated the beneficial effects of the n-butanolic extract of O. ficus-indica var. saboten (BOF) on memory performance in mice and attempts to uncover the mechanisms underlying its action. Memory performance was assessed with the passive avoidance task, and western blotting and immunohistochemistry were used to measure changes in protein expression and cell survival. After the oral administration of BOF for 7 days, the latency time in the passive avoidance task was significantly increased relative to vehicle-treated controls (P<0.05). Western blotting revealed that the expression levels of brain-derived neurotrophic factor (BDNF), phosphorylated cAMP response element binding-protein (pCREB), and phosphorylated extracellular signal-regulated kinase (pERK) 1/2 were significantly increased in hippocampal tissue after 7 days of BOF administration (P<0.05). Doublecortin and 5-bromo-2-deoxyuridine immunostaining also revealed that BOF significantly enhanced the survival of immature neurons, but did not affect neuronal cell proliferation in the subgranular zone of the hippocampal dentate gyrus. These results suggest that the subchronic administration of BOF enhances long-term memory, and that this effect is partially mediated by ERK-CREB-BDNF signaling and the survival of immature neurons. Copyright (c) 2010 Elsevier Inc. All rights reserved.

Study on passive immunity: Time of vaccination in kids born to goats vaccinated against Peste des petits ruminants.

PubMed

Balamurugan, Vinayagamurthy; Sen, Arnab; Venkatesan, Gnanavel; Rajak, Kaushal Kishor; Bhanuprakash, Veerakyathappa; Singh, Raj Kumar

2012-08-01

In this study, the decay of maternal peste des petits ruminants virus (PPRV) antibodies in kids born to goats vaccinated with Asian lineage IV PPR vaccine and the efficacy of passive immunity against PPRV was assessed to determine the appropriate period for vaccination in kids. Serum samples collected from kids born to vaccinated, unvaccinated and infected goats at different time intervals were tested by PPR competitive ELISA and serum neutralization test (SNT). Maternal antibodies in kids were detectable up to 6 months with a decline trend from the third month onwards and receded below the protective level by the fourth month. The kid with an SN titre of 1:8 at the time of immunization showed significant PPRV specific antibody response (percentage inhibition of 76; SN titers >1:16), when tested on 21 day post-vaccination and was completely protected from infection upon virulent PPRV challenge. Similarly, the kid with 1:8 SN titers was completely protected from PPR infection on active challenge. Therefore, PPR vaccination is recommended in kids, aged 4 months and born to immunized or exposed goats. This could be a suitable period to avoid window of susceptibility in kids to PPRV and the effort to eliminate PPR infection from susceptible populations.

7-Nitroindazole, a neuronal nitric oxide synthase inhibitor, impairs passive-avoidance and elevated plus-maze memory performance in rats.

PubMed

Yildiz Akar, Furuzan; Ulak, Guner; Tanyeri, Pelin; Erden, Faruk; Utkan, Tijen; Gacar, Nejat

2007-10-01

The role of nitric oxide (NO) on cognitive performance in a modified elevated plus-maze (mEPM) and passive-avoidance (PA) task was investigated by using the NO synthase (NOS) inhibitor 7-nitroindazole (7-NI) and an NO precursor l-arginine. The interaction between the activation of N-methyl-d-aspartate (NMDA) receptors and NO synthesis on memory retention was also studied. 7-NI, l-arginine or MK-801, a non-competitive NMDA receptor antagonist were injected intraperitoneally (i.p) to male Wistar rats 30 min before the first training session of the PA test or 30 min before on the first day testing (acquisition session) of mEPM task. Transfer latency, the time rat took to move from the open arm to the enclosed arm, was used as an index of learning and memory in a mEPM test. The retention session was performed 24 h after the acquisition one. In the PA task, the retention test was carried out 24 h after training and reduction of retention latency was used to evaluate the acquisition of learning and memory. Blood glucose level and locomotor activity of the rats was also evaluated. 7-NI (10, 20, 25, 50 mg/kg) and MK-801 (0.15 mg/kg) significantly prolonged the transfer latency on retention session in a mEPM test and shortened step-through latency in PA test. 7-NI-induced impairment in memory and learning was partly reversed by l-arginine (200 mg/kg), a competitive substrate for NOS. However subeffective doses of 7-NI (5 mg/kg) and MK-801 (0.075 mg/kg) given in combination significantly impaired plus-maze and PA performances in rats. Thus NMDA receptor mediated NO pathways may be implicated in the PA and mEPM behaviours in rats. Since 7-NI does not affect blood pressure and did not alter blood glucose level and locomotor activity in conscious rats, 7-NI-induced impairment of memory is not due to either hypertension, changes in blood glucose level or effects on locomotor activity.

Genotype-environment interaction in passive avoidance learning of the paradise fish (Macropodus opercularis).

PubMed

Csányi, V; Gervai, J

1985-01-01

Passive dark avoidance conditioning and effects of the presence and absence of a fish-like dummy on the training process were studied in four inbred strains of paradise fish. Strain differences were found in the shuttle activity during habituation trials, and in the sensitivity to the mild electric shock punishment. The presence or absence of the dummy in the punished dark side of the shuttle box had a genotype-dependent effect on the measures taken during the conditioning process. The statistical analysis of the learning curves revealed differences in the way the strains varied in the different environments, i.e. genotype--environment interaction components of variances were identified. The results are discussed in the light of previous investigations and their implication in further genetic analysis.

EXPANDING URBAN AMERICAN INDIAN YOUTHS’ REPERTOIRE OF DRUG RESISTANCE SKILLS: PILOT RESULTS FROM A CULTURALLY ADAPTED PREVENTION PROGRAM

PubMed Central

Kulis, Stephen; Dustman, Patricia A.; Brown, Eddie F.; Martinez, Marcos

2013-01-01

This article examines changes in the drug resistance strategies used by urban American Indian (UAI) middle school students during a pilot test of a substance use prevention curriculum designed specifically for UAI youth, Living in 2 Worlds (L2W). L2W teaches four drug resistance strategies (refuse, explain, avoid, leave [R-E-A-L]) in culturally appropriate ways. Data come from 57 UAI students (53% female; mean age = 12.5 years) who participated in L2W during an academic enrichment class for Native youth at two Phoenix schools. Students completed a pre-test questionnaire before the L2W lessons and a post-test 7 months later. Questions assessed the use of R-E-A-L and alternative strategies commonly reported by UAI youth (change the subject, use humor). Tests of mean differences from pre-test to post-test showed significant increases in use of refuse, R-E-A-L repertoire. Use of more passive strategies (avoid, use humor) did not change significantly, except for change the subject, which increased. Changes in the use of strategies did not differ significantly by gender, age, school grades, parental education, or length of urban residence. The L2W curriculum appears effective in teaching culturally relevant communication strategies that expand UAI youths’ repertoire of drug resistance skills. PMID:23529769

Choice of conflict resolution strategy is linked to sociability in dog puppies

PubMed Central

Riemer, Stefanie; Müller, Corsin; Virányi, Zsófia; Huber, Ludwig; Range, Friederike

2014-01-01

Measures that are likely to increase sociability in dog puppies, such as appropriate socialisation, are considered important in preventing future fear or aggression related problems. However, the interplay between sociability and conflict behaviour has rarely been investigated. Moreover, while many studies have addressed aggression in domestic dogs, alternative, non-aggressive conflict resolution strategies have received less scientific attention. Here we tested 134 Border collie puppies, aged 40-50 days, in a personality test which included friendly interactions with an unfamiliar person, exposure to a novel object, and three brief restraint tests. Considering the latter to be mild ‘conflict’ situations, we analysed whether the puppies’ behaviour in the restraint tests was related to their sociability or to their boldness towards the novel object. Strategies employed by the puppies during restraint tests included trying to interact socially with the experimenter, remaining passive, and attempting to move away. In line with findings from humans and goats, puppies scoring high on sociability were more likely to adopt an interactive conflict resolution strategy, while those with low sociability scores tended to react passively. In contrast, avoidance behaviours were unrelated to sociability, possibly reflecting inconsistency in the flight strategy in dogs. Boldness towards a novel object was not related to sociability or to puppies’ reactions in restraint tests. This is one of the first studies to demonstrate a link between sociability and conflict resolution strategies in non-human animals. PMID:24910487

Simultaneous passively Q-switched dual-wavelength solid-state laser working at 1065 and 1066 nm.

PubMed

Pallas, Florent; Herault, Emilie; Roux, Jean-Francois; Kevorkian, Antoine; Coutaz, Jean-Louis; Vitrant, Guy

2012-07-15

A passively Q-switched dual-wavelength solid-state laser is presented. The two wavelengths are emitted by two different crystals in order to avoid gain competition, and the synchronization between the pulses is obtained by external triggering of the saturable absorber. Sum frequency mixing is demonstrated, proving the interest of this source for terahertz generation in the 0.3-0.4 THz range through difference frequency generation.

Vitis labruscana leaf extract ameliorates scopolamine-induced impairments with activation of Akt, ERK and CREB in mice.

PubMed

Pariyar, Ramesh; Yoon, Chi-Su; Svay, Thida; Kim, Dae-Sung; Cho, Hyoung-Kwon; Kim, Sung Yeon; Oh, Hyuncheol; Kim, Youn-Chul; Kim, Jaehyo; Lee, Ho-Sub; Seo, Jungwon

2017-12-01

Grapes are among the most widely consumed plants and are used as a folk medicine. Vitis species have been traditionally used as anti-inflammatory, analgesic, and memory-enhancing agents, but, their biological activities of discarded grape leaves are not completely understood. We investigated the effects of alcoholic aqueous leaf extract of Vitis labruscana (LEVL) in a mouse model of memory impairment and tried to ascertain its mechanism. We also evaluated its effects in SH-SY5Y cells. LEVL (50, 100, and 150 mg/kg) was administered to ICR mice once daily for 7 days. Memory impairment was induced with intraperitoneal scopolamine injections (1 mg/kg) and measured with the Y-maze test and a passive avoidance task. LEVL-induced signaling was evaluated in SH-SY5Y cells and mouse hippocampi. We first identified quercetin-3-O-glucuronide as LEVL's major component. We then showed that LEVL promoted phosphorylation of Akt, extracellular regulated kinase (ERK), and cyclic AMP response element binding protein (CREB) and proliferation of SH-SY5Y cells. Oral LEVL administration (100 mg/kg) for 7 days significantly reversed scopolamine-induced reductions of spontaneous alternation in the Y-maze test and scopolamine-induced shortening of latency times in the passive avoidance task's retention trial. Consistent with the cell experiment results, LEVL restored scopolamine-decreased phosphorylation of Akt, ERK, and CREB and scopolamine-reduced expression of brain-derived neuroprotective factor expression in mouse hippocampi. Our results suggest that LEVL promotes phosphorylation of Akt, ERK, and CREB in the hippocampus and ameliorates scopolamine-induced memory impairment in mice. Copyright © 2017 Elsevier GmbH. All rights reserved.

Eating habits modulate short term memory and epigenetical regulation of brain derived neurotrophic factor in hippocampus of low- and high running capacity rats.

PubMed

Torma, Ferenc; Bori, Zoltan; Koltai, Erika; Felszeghy, Klara; Vacz, Gabriella; Koch, Lauren; Britton, Steven; Boldogh, Istvan; Radak, Zsolt

2014-08-01

Exercise capacity and dietary restriction (DR) are linked to improved quality of life, including enhanced brain function and neuro-protection. Brain derived neurotrophic factor (BDNF) is one of the key proteins involved in the beneficial effects of exercise on brain. Low capacity runner (LCR) and high capacity runner (HCR) rats were subjected to DR in order to investigate the regulation of BDNF. HCR-DR rats out-performed other groups in a passive avoidance test. BDNF content increased significantly in the hippocampus of HCR-DR groups compared to control groups (p<0.05). The acetylation of H3 increased significantly only in the LCR-DR group. However, chip-assay revealed that the specific binding between acetylated histone H3 and BNDF promoter was increased in both LCR-DR and HCR-DR groups. In spite of these increases in binding, at the transcriptional level only, the LCR-DR group showed an increase in BDNF mRNA content. Additionally, DR also induced the activity of cAMP response element-binding protein (CREB), while the content of SIRT1 was not altered. Peroxisome proliferator-activated receptor gamma coactivator-1 alpha (PGC-1α) was elevated in HCR-DR groups. But, based on the levels of nuclear respiratory factor-1 and cytocrome c oxidase, it appears that DR did not cause mitochondrial biogenesis. The data suggest that DR-mediated induction of BDNF levels includes chromatin remodeling. Moreover, DR does not induce mitochondrial biogenesis in the hippocampus of LCR/HCR rats. DR results in different responses to a passive avoidance test, and BDNF regulation in LCR and HCR rats. Copyright © 2014 Elsevier Inc. All rights reserved.

Haloperidol attenuates Methylphenidate and Modafinil induced behavioural sensitization and cognitive enhancement.

PubMed

Alam, Nausheen; Choudhary, Kulsoom

2018-06-01

Previous studies have demonstrated that repeated psychostimulant administration produces behavioural sensitization and cognitive tolerance. Brain dopaminergic system and the involvement of dopamine D 2 -receptors are considered to be important in psychostimulant-induced sensitization. Study designed to compared the motor activity by using familiar and novel enviroments and cognitive effects by water maze and passive avoidance test after long term administration of methylphenidate(at the dose 0.6 mg/kg/day, 2.5 mg/kg/day and 10 mg/kg/day) and modafinil (50 mg/kg/day, 64 mg/kg/day and 75 mg/kg/day) in rats. The effects of challenge dose of haloperidol (at the dose of 1 mg/kg i.p.) has monitored to visualize any subsensitization or supersensitization of D 2 receptors. We found that motor activity and cognitive performance was increased in all doses and sensitization effect was more pronounced after 13 days of drug administration were greater at high than low and medium doses.Challenge dose of haloperidol attenuate motor activity in familiar and novel environment and impaired cognition in water maze and passive avoidance test in all treated rats. The effect of Haloperidol in high dose treated rats were however somewhat greater than low and medium dose treated rats following methylphenidate and modafinil administration. Increased response of haloperidol in methylphenidate treated rats can be explained in term of supersensitization of D 2 receptors which is greater in high dose treated rats. The results show that the role of D 2 receptors to develop side effects such as behavioural sensitization and cognitive tolerance by the long term administration of psychostimulants is of sufficient importance and helpful in understanding the mechanisms underlying the undesirable effects of psychostimulants.

Cyanidin-3-O-galactoside and blueberry extracts supplementation improves spatial memory and regulates hippocampal ERK expression in senescence-accelerated mice.

PubMed

Tan, Long; Yang, Hong Peng; Pang, Wei; Lu, Hao; Hu, Yan Dan; Li, Jing; Lu, Shi Jun; Zhang, Wan Qi; Jiang, Yu Gang

2014-03-01

To investigate whether the antioxidation and the regulation on the Extracellular Regulated Protein Kinases (ERK) signaling pathway are involved in the protective effects of blueberry on central nervous system. 30 Senescence-accelerated mice prone 8 (SAMP8) mice were divided into three groups and treated with normal diet, blueberry extracts (200 mg/kg•bw/day) and cyaniding-3-O-galactoside (Cy-3-GAL) (50 mg/kg•bw/day) from blueberry for 8 weeks. 10 SAMR1 mice were set as control group. The capacity of spatial memory was assessed by Passive avoidance task and Morris water maze. Histological analyses on hippocampus were completed. Malondialdehyde (MDA) levels, Superoxide Dismutase (SOD) activity and the expression of ERK were detected. Both Cy-3-GAL and blueberry extracts were shown effective functions to relieve cellular injury, improve hippocampal neurons survival and inhibit the pyramidal cell layer damage. Cy-3-GAL and blueberry extracts also increased SOD activity and reduced MDA content in brain tissues and plasma, and increased hippocampal phosphorylated ERK (p-ERK) expression in SAMP8 mice. Further more, the passive avoidance task test showed that both the latency time and the number of errors were improved by Cy-3-GAL treatment, and the Morris Water Maze test showed significant decreases of latency were detected by Cy-3-GAL and blueberry extracts treatment on day 4. Blueberry extracts may reverse the declines of cognitive and behavioral function in the ageing process through several pathways, including enhancing the capacity of antioxidation, altering stress signaling. Cy-3-GAL may be an important active ingredient for these biological effects. Copyright © 2014 The Editorial Board of Biomedical and Environmental Sciences. Published by China CDC. All rights reserved.

Opposing effects of AMPA and 5-HT1A receptor blockade on passive avoidance and object recognition performance: correlation with AMPA receptor subunit expression in rat hippocampus.

PubMed

Schiapparelli, L; Simón, A M; Del Río, J; Frechilla, D

2006-06-01

It has been suggested that antagonists at serotonin 5-HT1A receptors may exert a procognitive effect by facilitating glutamatergic neurotransmission. Here we further explored this issue by looking for the ability of a 5-HT1A antagonist to prevent the learning deficit induced by AMPA receptor blockade in two behavioural procedures in rats, and for concomitant molecular changes presumably involved in memory formation in the hippocampus. Pretraining administration of the competitive AMPA receptor antagonist, NBQX, produced a dose-related retention impairment in a passive avoidance task 24h later, and also impaired retention in a novel object recognition test when an intertrial interval of 3h was selected. Pretreatment with the selective 5-HT1A receptor antagonist, WAY-100635, prevented the learning deficit induced by NBQX in the two behavioural procedures. In biochemical studies performed on rat hippocampus after the retention tests, we found that learning increased the membrane levels of AMPA receptor GluR1 and GluR2/3 subunits, as well as the phosphorylated forms of GluR1, effects that were abolished by NBQX administration before the training session. Pretreatment with WAY-100635 counteracted the NBQX effects and restored the initial learning-specific increase in Ca2+/calmodulin-dependent protein kinase II (CaMKII) function and the later increase in GluR2/3 and phosphorylated GluR1 surface expression. Moreover, administration of WAY-100635 before object recognition training improved recognition memory 24h later and potentiated the learning-associated increase in AMPA receptor subunits. The results support the proposed utility of 5-HT1A antagonists in the treatment of cognitive disorders.

Effects of ginseol k-g3, an Rg3-enriched fraction, on scopolamine-induced memory impairment and learning deficit in mice

PubMed Central

Peña, Ike dela; Yoon, Seo Young; Kim, Hee Jin; Park, Sejin; Hong, Eun Young; Ryu, Jong Hoon; Park, Il Ho; Cheong, Jae Hoon

2013-01-01

Background Although ginsenosides such as Rg1, Rb1 and Rg3 have shown promise as potential nutraceuticals for cognitive impairment, their use has been limited due to high production cost and low potency. In particular, the process of extracting pure Rg3 from ginseng is laborious and expensive. Methods We described the methods in preparing ginseol k-g3, an Rg3-enriched fraction, and evaluated its effects on scopolamine-induced memory impairment in mice. Results Ginseol k-g3 (25–200 mg/kg) significantly reversed scopolamine-induced cognitive impairment in the passive avoidance, but not in Y-maze testing. Ginseol k-g3 (50 and 200 mg/kg) improved escape latency in training trials and increased swimming times within the target zone of the Morris water maze. The effect of ginseol k-g3 on the water maze task was more potent than that of Rg3 or Red ginseng. Acute or subchronic (6 d) treatment of ginseol k-g3 did not alter normal locomotor activity of mice in an open field. Ginseol k-g3 did not inhibit acetylcholinesterase activity, unlike donezepil, an acetylcholinesterase inhibitor. Rg3 enrichment through the ginseol k-g3 fraction enhanced the efficacy of Rg3 in scopolamine-induced memory impairment in mice as demonstrated in the Morris water maze task. Conclusion The effects of ginseol k-g3 in ameliorating scopolamine-induced memory impairment in the passive avoidance and Morris water maze tests indicate its specific influence on reference or long-term memory. The mechanism underlying the reversal of scopolamine-induced amnesia by ginseol k-g3 is not yet known, but is not related to anticholinesterase-like activity. PMID:24558303

Repeated stressor exposure enhances contextual fear memory in a beta-adrenergic receptor-dependent process and increases impulsivity in a non-beta receptor-dependent fashion.

PubMed

Camp, Robert M; Johnson, John D

2015-10-15

Memory formation is promoted by stress via the release of norepinephrine and stimulation of beta-adrenergic receptors (β-ARs). Previous data demonstrate that repeated stressor exposure increases norepinephrine turnover and β-AR signaling within the amygdala, which led to the hypothesis that some stress-induced behavioral changes are likely due to facilitated associative learning. To test this, Fischer rats were exposed to chronic mild stress for four days. On day 5, subjects (including non-stressed controls) were injected with the beta-blocker propranolol or vehicle prior to conditioning in an operant box (animals receive two mild foot shocks) or passive avoidance apparatus (animals received a foot shock upon entry into the dark chamber). Twenty-four hours later, subjects were returned to the operant box for measurement of freezing or returned to the passive avoidance apparatus for measurement of latency to enter the dark chamber. Subjects were also tested in an open field to assess context-independent anxiety-like behavior. Animals exposed to chronic stress showed significantly more freezing behavior in the operant box than did controls, and this exaggerated freezing was blocked by propranolol during the conditioning trial. There was no effect of stress on behavior in the open field. Unexpectedly, retention latency was significantly reduced in subjects exposed to chronic stress. These results indicate that chronic exposure to stress results in complex behavioral changes. While repeated stress appears to enhance the formation of fearful memories, it also results in behavioral responses that resemble impulsive behaviors that result in poor decision-making. Copyright © 2015 Elsevier Inc. All rights reserved.

Thymoquinone recovers learning function in a rat model of Alzheimer’s disease

PubMed Central

Poorgholam, Parvin; Yaghmaei, Parichehreh; Hajebrahimi, Zahra

2018-01-01

Objective: Alzheimer's disease is a neurodegenerative disorder characterized by accumulation of amyloid beta in the hippocampus. In recent decades, herbal medicine has been widely used to treat many neurodegenerative disorders,as in comparison to conventional drugs, herbal remedies exert minimal side effects. Here, the effects of thymoquinone, as the main active component of Nigella sativa, on passive avoidance memory in rat model of Alzheimer’s disease, were evaluated. Materials and Methods: Hippocampal injection of amyloid beta (Aβ) was used to induce Alzheimer’s disease in male Wistar rats, followed by intra peritoneal administrations of 5 and 10 mg/kg thymoquinone on a daily basis for 4 weeks. Animals were subjected to fear learning behavior in passive avoidance test and histopathological analysis of the hippocampus was done. Shuttle box test was used to evaluate the condition studying memory. Thioflavin-S and Hematoxylin and Eosine staining were done to confirm Aβ plaque formation and to evaluate the effect of thymoquinone on the pyramidal cells in the hippocampal CA1 region. Results: Amyloid beta caused cognitive dysfunction reflected by increasing initial and step-through latency along with plaque formation and degeneration of pyramidal cells in the hippocampus. Thymoquinone administration ameliorated this effect by significant reductions in plaque formation in CA1 region of the hippocampus and increased latency time. It also increased the number of surviving neurons in the hippocampus. Conclusion: It seems that thymoquinone improved learning function in a rat model of Alzheimer’s disease. Thus, thymoquinone could be possibly used as an anti-neurodegenerative agent for protecting hippocampal neurons against neurotoxic effects of Aβ in patients with Alzheimer’s disease. PMID:29881705

Preliminary assessment of using tree-tissue analysis and passive-diffusion samplers to evaluate trichloroethene contamination of ground water at Site SS-34N, McChord Air Force Base, Washington, 2001

USGS Publications Warehouse

Cox, S.E.

2002-01-01

Two low-cost innovative sampling procedures for characterizing trichloroethene (TCE) contamination in ground water were evaluated for use at McChord Air Force Base (AFB) by the U.S. Geological Survey, in cooperation with the U.S. Air Force McChord Air Force Base Installation Restoration Program, in 2001. Previous attempts to characterize the source of ground-water contamination in the heterogeneous glacial outwash aquifer at McChord site SS-34N using soil-gas surveys, direct-push exploration, and more than a dozen ground-water monitoring wells have had limited success. The procedures assessed in this study involved analysis of tree-tissue samples to map underlying ground-water contamination and deploying passive-diffusion samplers to measure TCE concentrations in existing monitoring wells. These procedures have been used successfully at other U.S. Department of Defense sites and have resulted in cost avoidance and accelerated site characterization. Despite the presence of TCE in ground water at site SS-34N, TCE was not detected in any of the 20 trees sampled at the site during either early spring or late summer sampling. The reason the tree tissue procedure was not successful at the McChord AFB site SS-34N may have been due to an inability of tree roots to extract moisture from a water table 30 feet below the land surface, or that concentrations of TCE in ground water were not large enough to be detectable in the tree tissue at the sampling point. Passive-diffusion samplers were placed near the top, middle, and bottom of screened intervals in three monitoring wells and TCE was observed in all samplers. Concentrations of TCE from the passive-diffusion samplers were generally similar to concentrations found in samples collected in the same wells using conventional pumping methods. In contrast to conventional pumping methods, the collection of ground-water samples using the passive-diffusion samples did not generate waste purge water that would require hazardous-waste disposal. In addition, the results from the passive-diffusion samples may show that TCE concentrations are stratified across some screened intervals. The overall results of the limited test of passive-diffusion samplers at site SS-34N were similar to more detailed tests conducted at other contaminated sites across the country and indicate that further evaluation of the use of passive-diffusion samplers at McChord site SS-34N is warranted.

Evaluation of neuroprotective effect of quercetin with donepezil in scopolamine-induced amnesia in rats.

PubMed

Pattanashetti, Laxmi Adiveppa; Taranalli, Ashok D; Parvatrao, Vinay; Malabade, Rohit H; Kumar, Dushyant

2017-01-01

The objective of this study was to evaluate the neuroprotective effect of quercetin with donepezil in scopolamine-induced amnesia in rats. Five groups of adult male Wistar rats (12 months old) weighing 180-200 g ( n = 6) were used. The normal control group received normal saline and test group animals were pretreated orally with quercetin (25 mg/kg), donepezil (3 mg/kg), and a combination of quercetin (25 mg/kg) with donepezil (3 mg/kg), respectively, dosed at every 24 h interval for 14 consecutive days, afterward amnesia was induced by scopolamine (3 mg/kg) on the 14 th day through intraperitoneal route. Cognitive performance was assessed by the Morris water maze, elevated plus maze, and passive avoidance paradigm. Acetylcholinesterase enzyme (AchE) level, biochemical markers such as lipid peroxidase (LPO), glutathione (GSH), β amyloid 1-42 level, and histopathological study of rat brain were estimated. Statistical analysis was done by one-way analysis of variance, followed by Dunnett's post hoc test. P ≥ 0.05 was considered statistically significant. Pretreatment with quercetin, donepezil, and their combination showed a significant increase in escape latency, step-through latency, and decreased transfer latency in respective cognitive models of the Morris water maze, passive avoidance test, and elevated plus maze. Further coadministration significantly decreased AchE level, β amyloid 1-42 level as compared to individual therapy. Biochemical markers such as elevated GSH, decreased LPO were observed, and histopathological studies revealed the reversal of neuronal damage in the treatment group ( P < 0.05) as compared to scopolamine-treated control group. Pretreatment with quercetin potentiates the action of donepezil in scopolamine-induced amnesia in rats. The improved cognitive memory could be due to the synergistic effect of the drugs by decreasing AchE level, β amyloid 1-42 level, and antioxidant action in rat brain.

Evaluation of neuroprotective effect of quercetin with donepezil in scopolamine-induced amnesia in rats

PubMed Central

Pattanashetti, Laxmi Adiveppa; Taranalli, Ashok D.; Parvatrao, Vinay; Malabade, Rohit H.; Kumar, Dushyant

2017-01-01

Objective: The objective of this study was to evaluate the neuroprotective effect of quercetin with donepezil in scopolamine-induced amnesia in rats. Materials and Methods: Five groups of adult male Wistar rats (12 months old) weighing 180–200 g (n = 6) were used. The normal control group received normal saline and test group animals were pretreated orally with quercetin (25 mg/kg), donepezil (3 mg/kg), and a combination of quercetin (25 mg/kg) with donepezil (3 mg/kg), respectively, dosed at every 24 h interval for 14 consecutive days, afterward amnesia was induced by scopolamine (3 mg/kg) on the 14th day through intraperitoneal route. Cognitive performance was assessed by the Morris water maze, elevated plus maze, and passive avoidance paradigm. Acetylcholinesterase enzyme (AchE) level, biochemical markers such as lipid peroxidase (LPO), glutathione (GSH), β amyloid1-42level, and histopathological study of rat brain were estimated. Statistical analysis was done by one-way analysis of variance, followed by Dunnett's post hoc test. P ≥ 0.05 was considered statistically significant. Results: Pretreatment with quercetin, donepezil, and their combination showed a significant increase in escape latency, step-through latency, and decreased transfer latency in respective cognitive models of the Morris water maze, passive avoidance test, and elevated plus maze. Further coadministration significantly decreased AchE level, β amyloid1-42level as compared to individual therapy. Biochemical markers such as elevated GSH, decreased LPO were observed, and histopathological studies revealed the reversal of neuronal damage in the treatment group (P < 0.05) as compared to scopolamine-treated control group. Conclusion: Pretreatment with quercetin potentiates the action of donepezil in scopolamine-induced amnesia in rats. The improved cognitive memory could be due to the synergistic effect of the drugs by decreasing AchE level, β amyloid1-42level, and antioxidant action in rat brain. PMID:28458424

Pharmacokinetics and pharmacodynamics of a novel Acetylcholinesterase Inhibitor, DMNG-3.

PubMed

Xin-Guo, Zhang; Kou, Fei; Guo-Di, Ma; Tang, Peng; Zhong-Duo, Yang

2016-01-01

DMNG-3(3β-Methyl-[2-(4-nitrophenoxy)ethyl]-amino]con-5-enine), is a new and the potentially most potent acetylcholinesterase inhibitor recently obtained from conessine by N-demethylation and nucleophilic substitution reaction. In the present study, a step-down passive avoidance test was used to investigate whether DMNG-3 could modulate impairment of learning and memory induced by scopolamine, and a high performance liquid chromatography(HPLC) method for the determination of DMNG-3 in biological samples was applied to study its pharmacokinetics and tissues distribution. Separation was achieved on C18 column using a mobile phase consisting methanol-water (70:30, v/v) at a flow rate of 1.0ml/min. The intra- and inter-day precisions were good and the RSD was all lower than 1.30%. The mean absolute recovery of DMNG-3 in plasma ranged from 88.55 to 96.45 %. Our results showed oral administration of DMNG-3(10,25,50 mg/kg/day) can significantly improve the latency and number of errors and had a positive effect of improvement of learning and memory in mice in passive avoidance tests. The elimination half-life (T1/2) was 14.07±1.29, 15.87±1.03h, and the total clearance (CL) values were 0.70±0.11, 0.78±0.13 L/h/kg, respectively. The pharmacokinetic studies showed that DMNG-3 has a slowly clearance and large distribution volume in experimental animals, and its disposition is linear over the range of doses tested. The liver, small intestine, stomach, and large intestine were the major distribution tissues of DMNG-3 in mice. It was found that DMNG-3 could be detected in brain, suggesting that DMNG-3 can cross the blood-brain barrier. The present study shows that DMNG-3 can be possible developed as a new drug for the treatment of Alzheimer's disease in the future.

An IoT Reader for Wireless Passive Electromagnetic Sensors.

PubMed

Galindo-Romera, Gabriel; Carnerero-Cano, Javier; Martínez-Martínez, José Juan; Herraiz-Martínez, Francisco Javier

2017-03-28

In the last years, many passive electromagnetic sensors have been reported. Some of these sensors are used for measuring harmful substances. Moreover, the response of these sensors is usually obtained with laboratory equipment. This approach highly increases the total cost and complexity of the sensing system. In this work, a novel low-cost and portable Internet-of-Things (IoT) reader for passive wireless electromagnetic sensors is proposed. The reader is used to interrogate the sensors within a short-range wireless link avoiding the direct contact with the substances under test. The IoT functionalities of the reader allows remote sensing from computers and handheld devices. For that purpose, the proposed design is based on four functional layers: the radiating layer, the RF interface, the IoT mini-computer and the power unit. In this paper a demonstrator of the proposed reader is designed and manufactured. The demonstrator shows, through the remote measurement of different substances, that the proposed system can estimate the dielectric permittivity. It has been demonstrated that a linear approximation with a small error can be extracted from the reader measurements. It is remarkable that the proposed reader can be used with other type of electromagnetic sensors, which transduce the magnitude variations in the frequency domain.

An IoT Reader for Wireless Passive Electromagnetic Sensors

PubMed Central

Galindo-Romera, Gabriel; Carnerero-Cano, Javier; Martínez-Martínez, José Juan; Herraiz-Martínez, Francisco Javier

2017-01-01

In the last years, many passive electromagnetic sensors have been reported. Some of these sensors are used for measuring harmful substances. Moreover, the response of these sensors is usually obtained with laboratory equipment. This approach highly increases the total cost and complexity of the sensing system. In this work, a novel low-cost and portable Internet-of-Things (IoT) reader for passive wireless electromagnetic sensors is proposed. The reader is used to interrogate the sensors within a short-range wireless link avoiding the direct contact with the substances under test. The IoT functionalities of the reader allows remote sensing from computers and handheld devices. For that purpose, the proposed design is based on four functional layers: the radiating layer, the RF interface, the IoT mini-computer and the power unit. In this paper a demonstrator of the proposed reader is designed and manufactured. The demonstrator shows, through the remote measurement of different substances, that the proposed system can estimate the dielectric permittivity. It has been demonstrated that a linear approximation with a small error can be extracted from the reader measurements. It is remarkable that the proposed reader can be used with other type of electromagnetic sensors, which transduce the magnitude variations in the frequency domain. PMID:28350356

Elimination of Kalrn Expression in POMC Cells Reduces Anxiety-Like Behavior and Contextual Fear Learning

PubMed Central

Mandela, Prashant; Yan, Yan; LaRese, Taylor; Eipper, Betty A.; Mains, Richard E.

2014-01-01

Kalirin, a Rho GDP/GTP exchange factor for Rac1 and RhoG, is known to play an essential role in the formation and maintenance of excitatory synapses and in the secretion of neuropeptides. Mice unable to express any of the isoforms of Kalrn in cells that produce POMC at any time during development (POMC cells) exhibited reduced anxiety-like behavior and reduced acquisition of passive avoidance behavior, along with sex-specific alteration in the corticosterone response to restraint stress. Strikingly, lack of Kalrn expression in POMC cells closely mimicked the effects of global Kalrn knockout on anxiety-like behavior and passive avoidance conditioning without causing the other deficits noted in Kalrn knockout mice. Our data suggest that deficits in excitatory inputs onto POMC neurons are responsible for the behavioral phenotypes observed. PMID:25014196

Youth with substance abuse histories exhibit dysfunctional representation of expected value during a passive avoidance task.

PubMed

White, Stuart F; Tyler, Patrick; Botkin, Mary L; Erway, Anna K; Thornton, Laura C; Kolli, Venkata; Pope, Kayla; Meffert, Harma; Blair, R James

2016-11-30

Individuals with substance abuse (SA) histories show impairment in the computations necessary for decision-making, including expected value (EV) and prediction error (PE). Neuroimaging findings, however, have been inconsistent. Sixteen youth with (SA positive ) and 29 youth without (SA negative ) substance abuse histories completed a passive avoidance task while undergoing functional MRI. The groups did not significantly differ on age, gender composition or IQ. Behavioral results indicated that SA positive youth showed significantly less learning than SA negative youth over the task. SA positive youth show problems representing EV information when attempting to avoid sub-optimal choices in bilateral inferior frontal gyrus and striatum. Furthermore, SA positive youth showed a significantly increased differential response to reward versus punishment feedback modulated by PE in posterior cingulate cortex relative to SA negative youth. Disrupted decision-making is likely to exacerbate SA as a failure to represent EV during the avoidance of sub-optimal choices is likely to increase the likelihood of SA. With respect to the representation of PE, future work will be needed to clarify the impact of different substances on the neural systems underpinning PE representation. Moreover, interaction of age/development and substance abuse on PE signaling will need to be explored. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Nootropic effect of meadowsweet (Filipendula vulgaris) extracts.

PubMed

Shilova, I V; Suslov, N I

2015-03-01

The effects of the extracts of the aboveground parts of Filipendula vulgaris Moench on the behavior and memory of mice after hypoxic injury and their physical performance in the open-field test were studied using the models of hypoxia in a sealed volume, conditioned passive avoidance response (CPAR), and forced swimming with a load. The extracts improved animal resistance to hypoxia, normalized orientation and exploration activities, promoted CPAR retention after hypoxic injury, and increased physical performance. Aqueous extract of meadowsweet had the most pronounced effect that corresponded to the effect of the reference drug piracetam. These effects were probably caused by modulation of hippocampal activity.

Thujone inhibits the function of α7-nicotinic acetylcholine receptors and impairs nicotine-induced memory enhancement in one-trial passive avoidance paradigm.

PubMed

Sultan, Ahmed; Yang, Keun-Hang Susan; Isaev, Dmitro; Nebrisi, Eslam El; Syed, Nurulain; Khan, Nadia; Howarth, Christopher F; Sadek, Bassem; Oz, Murat

2017-06-01

Effects of thujone, a major ingredient of absinthe, wormwood oil and some herbal medicines, were tested on the function of α 7 subunit of the human nicotinic acetylcholine (α 7 nACh) receptor expressed in Xenopus oocytes using the two-electrode voltage-clamp technique. Thujone reversibly inhibited ACh (100μM)-induced currents with an IC 50 value of 24.7μM. The effect of thujone was not dependent on the membrane potential and did not involve Ca 2+ -dependent Cl - channels expressed endogenously in oocytes. Inhibition by thujone was not reversed by increasing ACh concentrations. Moreover, specific binding of [ 125 I] α-bungarotoxin was not altered by thujone. Further experiments in SH-EP1 cells expressing human α 7 nACh receptor indicated that thujone suppressed choline induced Ca 2+ transients in a concentration-dependent manner. In rat hippocampal CA3-dentate gyrus synapses, nicotine-induced enhancement of long-term potentiation was also inhibited by thujone. Furthermore, the results observed in in-vivo one-trial passive avoidance paradigm show that thujone (1.25mg/kg, i.p.) significantly impaired nicotine-induced enhancement of learning and memory in Wistar rats. Collectively, our results indicate that thujone inhibits the function of the α7-nACh receptor and impairs cellular and behavioral correlates of cholinergic modulation of learning and memory. Copyright © 2017 Elsevier B.V. All rights reserved.

Velocity filtering applied to optical flow calculations

NASA Technical Reports Server (NTRS)

Barniv, Yair

1990-01-01

Optical flow is a method by which a stream of two-dimensional images obtained from a forward-looking passive sensor is used to map the three-dimensional volume in front of a moving vehicle. Passive ranging via optical flow is applied here to the helicopter obstacle-avoidance problem. Velocity filtering is used as a field-based method to determine range to all pixels in the initial image. The theoretical understanding and performance analysis of velocity filtering as applied to optical flow is expanded and experimental results are presented.

Effects of a Novel Acoustic Transmitter on Swimming Performance and Predator Avoidance of Juvenile Chinook Salmon: Determination of a Size Threshold

DOE Office of Scientific and Technical Information (OSTI.GOV)

Walker, Ricardo W.; Ashton, Neil K.; Brown, Richard S.

Abstract Telemetry studies are used worldwide to investigate the behavior and migration of fishes. The miniaturization of acoustic transmitters enables researchers to tag smaller fish, such as the juvenile life stages of salmon, thus representing a greater proportion of the population of interest. The development of an injectable acoustic transmitter has led to research determining the least invasive and quickest method of tag implantation. Swimming performance and predator avoidance were examined. To quantify critical swimming speed (Ucrit; an index of prolonged swimming performance) and predator avoidance for juvenile Chinook salmon (Oncorhynchus tshawytscha), fish were split into three groups: (1) fishmore » implanted with a dummy injectable acoustic transmitter (IAT treatment), (2) fish implanted with a dummy injectable acoustic transmitter and passive integrated transponder (PIT) tag (IAT+PIT treatment), and (3) an untagged control group. The Ucrits and predator avoidance capability of tagged fish were compared with untagged fish to determine if carrying an IAT adversely affected swimming performance or predator avoidance. Fish implanted with only an IAT had lower Ucrit values than untagged fish and a size threshold at 79 mm fork length was found. Conversely, Ucrit values for fish implanted with an IAT+PIT were not significantly different from untagged controls and no size threshold was found. Predator avoidance testing showed no significant difference for fish implanted with an IAT compared to untagged individuals, nor was there a significant difference for IAT+PIT fish compared to untagged fish.« less

Passive versus active hazard detection and avoidance systems

NASA Astrophysics Data System (ADS)

Neveu, D.; Mercier, G.; Hamel, J.-F.; Simard Bilodeau, V.; Woicke, S.; Alger, M.; Beaudette, D.

2015-06-01

Upcoming planetary exploration missions will require advanced guidance, navigation and control technologies to reach landing sites with high precision and safety. Various technologies are currently in development to meet that goal. Some technologies rely on passive sensors and benefit from the low mass and power of such solutions while others rely on active sensors and benefit from an improved robustness and accuracy. This paper presents two different hazard detection and avoidance (HDA) system design approaches. The first architecture relies only on a camera as the passive HDA sensor while the second relies, in addition, on a Lidar as the active HDA sensor. Both options use in common an innovative hazard map fusion algorithm aiming at identifying the safest landing locations. This paper presents the simulation tools and reports the closed-loop software simulation results obtained using each design option. The paper also reports the Monte Carlo simulation campaign that was used to assess the robustness of each design option. The performance of each design option is compared against each other in terms of performance criteria such as percentage of success, mean distance to nearest hazard, etc. The applicability of each design option to planetary exploration missions is also discussed.

The replacement of dry heat in generic reliability assurance requirements for passive optical components

NASA Astrophysics Data System (ADS)

Ren, Xusheng; Qian, Longsheng; Zhang, Guiyan

2005-12-01

According to Generic Reliability Assurance Requirements for Passive Optical Components GR-1221-CORE (Issue 2, January 1999), reliability determination test of different kinds of passive optical components which using in uncontrolled environments is taken. The test condition of High Temperature Storage Test (Dry Test) and Damp Test is in below sheet. Except for humidity condition, all is same. In order to save test time and cost, after a sires of contrast tests, the replacement of Dry Heat is discussed. Controlling the Failure mechanism of dry heat and damp heat of passive optical components, the contrast test of dry heat and damp heat for passive optical components (include DWDM, CWDM, Coupler, Isolator, mini Isolator) is taken. The test result of isolator is listed. Telcordia test not only test the reliability of the passive optical components, but also test the patience of the experimenter. The cost of Telcordia test in money, manpower and material resources, especially in time is heavy burden for the company. After a series of tests, we can find that Damp heat could factually test the reliability of passive optical components, and equipment manufacturer in accord with component manufacture could omit the dry heat test if damp heat test is taken first and passed.

Method to improve passive fit of frameworks on implant-supported prostheses: An in vitro study.

PubMed

Manzella, Carlo; Bignardi, Cristina; Burello, Valerio; Carossa, Stefano; Schierano, Gianmario

2016-07-01

The passivity of the superstructure to the abutments of implant-supported prostheses is necessary for implant-prosthesis success. Improvements are needed in the methods of verifying passivity. The purpose of this in vitro study was to evaluate an inexpensive, easy to make, and user-friendly device to verify the position of the implant abutment replicas of the definitive cast and to avoid framework misfit before fabrication. Eighty stone devices were constructed on a metal base for the in vitro tests. The horizontal, vertical, and angled positions of the implant replicas were created to simulate misfits. The devices were fitted on the abutment replicas, and their ability to identify misfits was evaluated. A statistical analysis was not indicated, because the probability of fracture of the stone devices was 0 or 1. Two mathematical models were built using computer-aided design software (SolidWorks Premium; Dassault Systèmes SolidWorks Corp), and the finite element method was used (Ansys; ANSYS Inc) to simulate the structural behavior of 2 implant configurations (4 and 6 implants). Horizontal misfits of 150 μm, vertical misfits of 50 μm, and angled misfits of 1 degree were detected during the in vitro tests. Different loads and bone quality in the mathematical models did not change stress in the prosthesis configurations on 4 or 6 implants in a relevant way. The fabricated device was easily able to detect the misfits in accordance with the defined parameters. Copyright © 2016 Editorial Council for the Journal of Prosthetic Dentistry. Published by Elsevier Inc. All rights reserved.

[Comparative study of the long-term behavioral effects of noopept and piracetam in adult male rats and female rats in postnatal period].

PubMed

Voronina, T A; Guzevatykh, L S; Trofimov, S S

2005-01-01

Adult male and female rats were treated with the peptide nootrope drug noopept (daily dose, 0.1 mg/kg) and piracetam (200 mg/kg). In the period from 8th to 20th day, both drugs (cognitive enhancers) suppressed the horizontal and vertical activity and the anxiety in test animals as compared to the control group treated with 0.9 % aqueous NaCl solution. Early postnatal injections of the nootropes influenced neither the morphology development nor the behavior of adult female rats in the plus maze, extrapolational escape, passive avoidance, and pain sensitivity threshold tests. Animals in the "intact" group (having received neither drugs not physiological solution, that is, developing in a poor sensor environment), showed less pronounced habituation in the open field test as compared to the control and drug treated groups.

Passive appendages improve the maneuverability of fish-like robots

NASA Astrophysics Data System (ADS)

Pollard, Beau; Tallapragada, Phanindra

2017-11-01

It is known that the passive mechanics of fish appendages play a role in the high efficiency of their swimming. A well known example of this is the experimental demonstration that a dead fish could swim upstream. However little is known about the role if any of passive deformations of a fish-like body that could aid in its maneuverability. Part of the difficulty investigating this lies in clearly separating the role of actuated body deformations and passive deformations in response to the fluid structure interaction. In this paper we compare the maneuverability of several fish shaped robotic models that possess varying numbers of passive appendages with a fish shaped robot that has no appendages. All the robots are propelled by the oscillations of an internal momentum wheel thereby eliminating any active deformations of the body. Our experiments clearly reveal the significant improvement in maneuverability of robots with passive appendages. In the broader context of swimming robots our experiments show that passive mechanisms could be useful to provide mechanical feedback that can help maneuverability and obstacle avoidance along with propulsive efficiency. This work was partly supported by a Grant from the NSF CMMI 1563315.

Opposite roles for neuropeptide S in the nucleus accumbens and bed nucleus of the stria terminalis in learned helplessness rats.

PubMed

Shirayama, Yukihiko; Ishima, Tamaki; Oda, Yasunori; Okamura, Naoe; Iyo, Masaomi; Hashimoto, Kenji

2015-09-15

The role of neuropeptide S (NPS) in depression remains unclear. We examined the antidepressant-like effects of NPS infusions into the shell or core regions of the nucleus accumbens (NAc) and into the bed nucleus of the stria terminalis (BNST) of learned helplessness (LH) rats (an animal model of depression). Infusions of NPS (10 pmol/side) into the NAc shell, but not the NAc core and BNST, exerted antidepressant-like effects in the LH paradigm. Implying that behavioral deficits could be improved in the conditioned avoidance test. Coinfusion of SHA68 (an NPS receptor antagonist, 100 pmol/side) with NPS into the NAc shell blocked these effects. In contrast, NPS receptor antagonism by SHA68 in the BNST induced antidepressant-like effects. Infusions of NPS into the NAc shell or SHA68 into the BNST did not produce memory deficits or locomotor activation in the passive avoidance and open field tests. These results suggest that excitatory and inhibitory actions by the NPS system are integral to the depression in LH animals. Copyright © 2015 Elsevier B.V. All rights reserved.

Thermal human phantom for testing of millimeter wave cameras

NASA Astrophysics Data System (ADS)

Palka, Norbert; Ryniec, Radoslaw; Piszczek, Marek; Szustakowski, Mieczyslaw; Zyczkowski, Marek; Kowalski, Marcin

2012-06-01

Screening cameras working in millimetre band gain more and more interest among security society mainly due to their capability of finding items hidden under clothes. Performance of commercially available passive cameras is still limited due to not sufficient resolution and contrast in comparison to other wavelengths (visible or infrared range). Testing of such cameras usually requires some persons carrying guns, bombs or knives. Such persons can have different clothes or body temperature, what makes the measurements even more ambiguous. To avoid such situations we built a moving phantom of human body. The phantom consists of a polystyrene manikin which is covered with a number of small pipes with water. Pipes were next coated with a silicone "skin". The veins (pipes) are filled with water heated up to 37 C degrees to obtain the same temperature as human body. The phantom is made of non-metallic materials and is placed on a moving wirelessly-controlled platform with four wheels. The phantom can be dressed with a set of ordinary clothes and can be equipped with some dangerous (guns, bombs) and non-dangerous items. For tests we used a passive commercially available camera TS4 from ThruVision Systems Ltd. operating at 250 GHz. We compared the images taken from phantom and a man and we obtained good similarity both for naked as well as dressed man/phantom case. We also tested the phantom with different sets of clothes and hidden items and we got good conformity with persons.

Memory Formation: Evidence for a Specific Neurochemical System in the Amygdala

ERIC Educational Resources Information Center

Gallagher, Michela; And Others

1977-01-01

Reports bita-Adrenergic antagonists injected into rats trained in a passive avoidance task produced time-dependent and dose-dependent decreases in retention of the task. Results were stereospecific and reversed by norepinephrine. (SL)

Aircraft wake vortex measurements at Denver International Airport

DOT National Transportation Integrated Search

2004-05-10

Airport capacity is constrained, in part, by spacing requirements associated with the wake vortex hazard. NASA's Wake Vortex Avoidance Project has a goal to establish the feasibility of reducing this spacing while maintaining safety. Passive acoustic...

Li-air batteries: Decouple to stabilize

NASA Astrophysics Data System (ADS)

Xu, Ji-Jing; Zhang, Xin-Bo

2017-09-01

The utilization of porous carbon cathodes in lithium-air batteries is hindered by their severe decomposition during battery cycling. Now, dual redox mediators are shown to decouple the complex electrochemical reactions at the cathode, avoiding cathode passivation and decomposition.

Elimination of Kalrn expression in POMC cells reduces anxiety-like behavior and contextual fear learning.

PubMed

Mandela, Prashant; Yan, Yan; LaRese, Taylor; Eipper, Betty A; Mains, Richard E

2014-07-01

Kalirin, a Rho GDP/GTP exchange factor for Rac1 and RhoG, is known to play an essential role in the formation and maintenance of excitatory synapses and in the secretion of neuropeptides. Mice unable to express any of the isoforms of Kalrn in cells that produce POMC at any time during development (POMC cells) exhibited reduced anxiety-like behavior and reduced acquisition of passive avoidance behavior, along with sex-specific alteration in the corticosterone response to restraint stress. Strikingly, lack of Kalrn expression in POMC cells closely mimicked the effects of global Kalrn knockout on anxiety-like behavior and passive avoidance conditioning without causing the other deficits noted in Kalrn knockout mice. Our data suggest that deficits in excitatory inputs onto POMC neurons are responsible for the behavioral phenotypes observed. Copyright © 2014 Elsevier Inc. All rights reserved.

Coping behavior and loneliness among obese patients.

PubMed

Hörchner, Rogier; Tuinebreijer, Wim E; Kelder, Hans; van Urk, Elly

2002-12-01

Morbid obesity can be accompanied by physical and social problems that may influence interpersonal relationships and the recruitment of social support. The problems can be tackled with a variety of coping strategies. 104 patients with a body mass index (BMI) 32-64 kg/m2 and mean age 36 yr were presented with the Utrecht Coping List (UCL) and the Loneliness Scale. Of these patients, 94 were female, and this cohort was analyzed more extensively. Patients exhibited elevated values on the Loneliness Scale and in the UCL sub-scales palliative response, avoidance / wait-and-see, passive / depressive response pattern and expression of emotions / anger. The active approach UCL sub-scale scored lower than in a control group. Obese female patients displayed avoidance, wait-and-see and passive response pattern as coping behavior, experiencing their intimate relationships as relatively unreliable and not very intimate. More research is needed to determine the effect of coping behavior on therapeutic effect.

Effects of D-cycloserine and aniracetam on spatial learning in rats with entorhinal cortex lesions.

PubMed

Zajaczkowski, W; Danysz, W

1997-01-01

A great body of behavioural and neurophysiological evidence suggests that excitatory amino acids are involved in mechanisms of learning and memory. Moreover, degeneration of glutamatergic pathways may underlie the cognitive deficits seen in various disorders such as Alzheimer's dementia. As direct stimulation of glutamatergic receptors with agonists may increase the risk of toxicity and accelerate neuropathological changes, a more valid approach seems to be positive modulation of glutamatergic receptors that may reverse the symptoms with a lower risk of excitotoxic effects. Such a possibility offered by partial agonists of the strychnine-insensitive glycine site of the NMDA receptor (Gly-B site) or positive modulators of AMPA receptors, such as aniracetam. In the present study, the effects of d-cycloserine and aniracetam were tested in two animal models of cognitive deficits (entorhinal cortex lesion-induced deficits evaluated in the radial maze and scopolamine-induced amnesia evaluated in passive avoidance test). D-cycloserine (6 mg/kg, for 10 days) had no effect on spatial working memory deficit induced by entorhinal cortex lesions. It did, however, reverse scopolamine-induced deficits in the passive avoidance test when given acutely at the same dose. In contrast, aniracetam (50 mg/kg, for 10 days) produced beneficial effects in the radial maze test in rats with entorhinal cortex lesions, but given at the same dose acutely did not influence scopolamine-induced amnesia. The positive effect of d-cycloserine against scopolamine-induced amnesia may be probably related to the cholinergic-glutamatergic interaction in the hippocampus. The negative data obtained with d-cycloserine in the model of entorhinal cortex lesions-induced cognitive deficits could be taken as a hint that it is probably not suitable for the symptomatological therapy of Alzheimer's disease. The mechanism of positive action of aniracetam cannot be explained on the basis of AMPA receptor modulation, as the dose used (50 mg/kg) is well below that required for the effect at AMPA receptors. Other actions such as peripheral effects or modulation of metabotropic receptors seem more likely.

Verb-based versus class-based accounts of actionality effects in children's comprehension of passives.

PubMed

Gordon, P; Chafetz, J

1990-09-01

Several studies have shown that children perform worse on tests of passive comprehension when the verb is non-actional than when it is actional. Most existing accounts focus on the semantic characteristics of the class of non-action verbs in explaining this difference. An alternative is a "verb-based" account in which passives are initially learned verb by verb, and children hear fewer non-actional passives in their language input. An analysis of the passives heard by Adam, Eve and Sarah (Brown, 1973) found more actional than non-actional passives, consistent with the verb-based account. In a second study, children tested for passive comprehension were re-tested a week later. The verb-based account predicts that children should show a consistent pattern of responses for individual verbs on test and re-test. Such consistency was found, with some inconsistency due to improvement over the re-test. Further analyses showed no effects of affectedness in explaining children's problems with passives. Finally, we discuss whether a mixed model containing both verb-based and class-based mechanisms is required to explain the actionality effects.

Rapamycin blocks the antidepressant effect of ketamine in task-dependent manner.

PubMed

Holubova, Kristina; Kleteckova, Lenka; Skurlova, Martina; Ricny, Jan; Stuchlik, Ales; Vales, Karel

2016-06-01

The aim of our study was to test whether ketamine produces an antidepressant effect in animal model of olfactory bulbectomy and assess the role of mammalian target of rapamycin (mTOR) pathway in ketamine's antidepressant effect. Bulbectomized (OBX) rats and sham controls were assigned to four subgroups according to the treatment they received (ketamine, saline, ketamine + rapamycin, and saline + rapamycin). The animals were subjected to open field (OF), elevated plus maze (EPM), passive avoidance (PA), Morris water maze (MWM), and Carousel maze (CM) tests. Blood samples were collected before and after drug administration for analysis of phosphorylated mTOR level. After behavioral testing, brains were removed for evaluation of brain-derived neurotrophic factor (BDNF) in prefrontal cortex (PFC) and hippocampus. Ketamine normalized hyperactivity of OBX animals in EPM and increased the time spent in open arms. Rapamycin pretreatment resulted in elimination of ketamine effect in EPM test. In CM test, ketamine + rapamycin administration led to cognitive impairment not observed in saline-, ketamine-, or saline + rapamycin-treated OBX rats. Prefrontal BDNF content was significantly decreased, and level of mTOR was significantly elevated in OBX groups. OBX animals significantly differed from sham controls in most of the tests used. Treatment had more profound effect on OBX phenotype than controls. Pretreatment with rapamycin eliminated the anxiolytic and antidepressant effects of ketamine in task-dependent manner. The results indicate that ketamine + rapamycin application resulted in impaired stress responses manifested by cognitive deficits in active place avoidance (CM) test. Intensity of stressor (mild vs. severe) used in the behavioral tests had opposite effect on controls and on OBX animals.

Understanding avoidant leadership in health care: findings from a secondary analysis of two qualitative studies.

PubMed

Jackson, Debra; Hutchinson, Marie; Peters, Kath; Luck, Lauretta; Saltman, Deborah

2013-04-01

To illuminate ways that avoidant leadership can be enacted in contemporary clinical settings. Avoidance is identified in relation to laissez-faire leadership and passive avoidant leadership. However, the nature and characteristics of avoidance and how it can be enacted in a clinical environment are not detailed. This paper applied secondary analysis to data from two qualitative studies. We have identified three forms of avoidant leader response: placating avoidance, where leaders affirmed concerns but abstained from action; equivocal avoidance, where leaders were ambivalent in their response; and hostile avoidance, where the failure of leaders to address concerns escalated hostility towards the complainant. Through secondary analysis of two existing sets of data, we have shed new light on avoidant leaderships and how it can be enacted in contemporary clinical settings. Further work needs to be undertaken to better understand this leadership style. We recommend that organizations ensure that all nurse leaders are aware of how best to respond to concerns of wrongdoing and that mechanisms are created to ensure timely feedback is provided about the actions taken. © 2012 Blackwell Publishing Ltd.

A symmetrical method to obtain shear moduli from microrheology.

PubMed

Nishi, Kengo; Kilfoil, Maria L; Schmidt, Christoph F; MacKintosh, F C

2018-05-16

Passive microrheology typically deduces shear elastic loss and storage moduli from displacement time series or mean-squared displacements (MSD) of thermally fluctuating probe particles in equilibrium materials. Common data analysis methods use either Kramers-Kronig (KK) transformation or functional fitting to calculate frequency-dependent loss and storage moduli. We propose a new analysis method for passive microrheology that avoids the limitations of both of these approaches. In this method, we determine both real and imaginary components of the complex, frequency-dependent response function χ(ω) = χ'(ω) + iχ''(ω) as direct integral transforms of the MSD of thermal particle motion. This procedure significantly improves the high-frequency fidelity of χ(ω) relative to the use of KK transformation, which has been shown to lead to artifacts in χ'(ω). We test our method on both model and experimental data. Experiments were performed on solutions of worm-like micelles and dilute collagen solutions. While the present method agrees well with established KK-based methods at low frequencies, we demonstrate significant improvement at high frequencies using our symmetric analysis method, up to almost the fundamental Nyquist limit.

Middle-aged human apoE4 targeted-replacement mice show retention deficits on a wide range of spatial memory tasks.

PubMed

Bour, Alexandra; Grootendorst, Jeannette; Vogel, Elise; Kelche, Christian; Dodart, Jean-Cosme; Bales, Kelly; Moreau, Pierre-Henri; Sullivan, Patrick M; Mathis, Chantal

2008-11-21

Apolipoprotein (apo) E4, one of three human apoE (h-apoE) isoforms, has been identified as a major genetic risk factor for Alzheimer's disease and for cognitive deficits associated with aging. However, the biological mechanisms involving apoE in learning and memory processes are unclear. A potential isoform-dependent role of apoE in cognitive processes was studied in human apoE targeted-replacement (TR) mice. These mice express either the human apoE3 or apoE4 gene under the control of endogenous murine apoE regulatory sequences, resulting in physiological expression of h-apoE in both a temporal and spatial pattern similar to humans. Male and female apoE3-TR, apoE4-TR, apoE-knockout and C57BL/6J mice (15-18 months) were tested with spatial memory and avoidance conditioning tasks. Compared to apoE3-TR mice, spatial memory in female apoE4-TR mice was impaired based on their poor performances in; (i) the probe test of the water-maze reference memory task, (ii) the water-maze working memory task and (iii) an active avoidance Y-maze task. Retention performance on a passive avoidance task was also impaired in apoE4-TR mice, but not in other genotypes. These deficits in both spatial and avoidance memory tasks may be related to the anatomical and functional abnormalities previously reported in the hippocampus and the amygdala of apoE4-TR mice. We conclude that the apoE4-TR mice provide an excellent model for understanding the mechanisms underlying apoE4-dependent susceptibility to cognitive decline.

Personality factors and posttraumatic stress: associations in civilians one year after air attacks.

PubMed

Lecic-Tosevski, Dusica; Gavrilovic, Jelena; Knezevic, Goran; Priebe, Stefan

2003-12-01

There is an ongoing debate on which risk factors for developing posttraumatic stress symptoms are more important--personality traits reflecting vulnerability, previous stressful experiences or characteristics of the traumatic event. In this study, posttraumatic stress symptoms and their relationship with personality traits, previous stressful experiences and exposure to stressful events during air attacks in Yugoslavia were investigated. The Millon Clinical Multiaxial Inventory (MCMI; Millon, 1983), Impact of Events Scale (IES; Horowitz, Wilner, & Alvarez, 1979), Life Stressor Checklist Revised (LSCL-R; Wolfe & Kimerling, 1997), and List of Stressors were administered to a homogeneous group of medical students 1 year after the attacks. In multiple regression analyses, compulsive and passive-aggressive personality traits and a higher level of exposure to stressors during air attacks independently predicted the degree of intrusion symptoms. Avoidance symptoms were predicted by avoidant personality traits and a higher exposure to stressors both previously in life and during the attacks. In the next step, we tested in analyses of variance whether personality traits, previous stressful experiences, and stressful events during attacks as independent variables interact in predicting intrusion and avoidance symptoms. For this, students were clustered into three groups depending on their predominant personality traits. In addition to direct predictive effects, there were significant interaction effects in predicting both intrusion and avoidance. The findings suggest that each of the tested factors, i.e., personality traits, previous stressful experiences, and exposure to traumatic events may have an independent and direct influence on developing posttraumatic stress. However, the effect of these factors cannot just be added up. Rather, the factors interact in their impact on posttraumatic stress symptoms. Bigger samples and longitudinal designs will be required to understand precisely how different personality traits influence response to stressful events.

Germanium detector passivated with hydrogenated amorphous germanium

DOEpatents

Hansen, William L.; Haller, Eugene E.

1986-01-01

Passivation of predominantly crystalline semiconductor devices (12) is provided for by a surface coating (21) of sputtered hydrogenated amorphous semiconductor material. Passivation of a radiation detector germanium diode, for example, is realized by sputtering a coating (21) of amorphous germanium onto the etched and quenched diode surface (11) in a low pressure atmosphere of hydrogen and argon. Unlike prior germanium diode semiconductor devices (12), which must be maintained in vacuum at cryogenic temperatures to avoid deterioration, a diode processed in the described manner may be stored in air at room temperature or otherwise exposed to a variety of environmental conditions. The coating (21) compensates for pre-existing undesirable surface states as well as protecting the semiconductor device (12) against future impregnation with impurities.

[Changes in proline-specific peptidase activity in experimental model of retrograde amnesia].

PubMed

Nazarova, G A; Zolotov, N N; Krupina, N A; Kraĭneva, V A; Garibova, T L; Voronina, T A

2007-01-01

Changes in proline-specific peptidase activity in the frontal cortex and hippocampus were studied using the experimental model of retrograde amnesia in rats. In one group, the amnesia was produced by a single injection of M-cholinergic antagonist scopolamine and the other group received the maximal electroconvulsive stimulation (MES). The amnesic effect was evaluated in passive avoidance test. In the amnesia models under consideration, the activity of prolylendopeptidase was significantly increased in both frontal cortex and hippocampus. The activity of dipeptidyl peptidase IV was significantly decreased in the cortex, whereas in the hippocampus it remained unchanged. Pyracetam inhibited prolylendopeptidase in the cortex and hippocampus, whereas dipeptidyl peptidase IV activity remained unchanged.

Nitric oxide in the dorsal hippocampal area is involved on muscimol state-dependent memory in the step-down passive avoidance test.

PubMed

Jafari-Sabet, Majid; Khodadadnejad, Mohammad-Amin; Ghoraba, Saeed; Ataee, Ramin

2014-02-01

In the present study, the effects of intra-dorsal hippocampal (intra-CA1) injections of nitric oxide (NO) agents on muscimol state-dependent memory were examined in mice. A single-trial step-down passive avoidance task was used for the assessment of memory retrieval in adult male NMRI mice. Post-training intra-CA1 administration of a GABAA receptor agonist, muscimol (0.05 and 0.1 μg/mouse) dose dependently induced impairment of memory retention. Pre-test injection of muscimol (0.05 and 0.1 μg/mouse) induced state-dependent retrieval of the memory acquired under post-training muscimol (0.1 μg/mouse, intra-CA1) influence. Pre-test injection of a NO precursor, L-arginine (1 and 2 μg/mouse, intra-CA1) improved memory retention, although the low dose of the drug (0.5 μg/mouse) did not affect memory retention. Pre-test injection of an inhibitor of NO-synthase, L-NAME (0.5 and 1 μg/mouse, intra-CA1) impaired memory retention, although the low dose of the drug (0.25 μg/mouse) did not affect memory retention. In other series of experiments, pre-test intra-CA1 injection of L-arginine (0.25 and 0.5 μg/mouse) 5 min before the administration of muscimol (0.1 μg/mouse, intra-CA1) dose dependently inhibited muscimol state-dependent memory. Pre-test intra-CA1 administration of L-arginine (0.125, 0.25 and 0.5 μg/mouse) by itself cannot affect memory retention. Pre-test intra-CA1 injection of L-NAME (0.25 μg/mouse, intra-CA1) reversed the memory impairment induced by post-training administration of muscimol (0.1 μg/mouse, intra-CA1). Moreover, pre-test administration of L-NAME (0.125 and 0.25 μg/mouse, intra-CA1) with an ineffective dose of muscimol (0.025 μg/mouse, intra-CA1) significantly restored the retrieval and induced muscimol state-dependent memory. Pre-test intra-CA1 administration of L-NAME (0.0625, 0.125 and 0.25 μg/mouse) by itself cannot affect memory retention. It may be suggested that the nitric oxide in the dorsal hippocampal area play an important role in muscimol state-dependent memory. Copyright © 2013 Elsevier Inc. All rights reserved.

Chronic infusion of GABA and saline into the nucleus basalis magnocellularis of rats: II. Cognitive impairments.

PubMed

Majchrzak, M; Brailowsky, S; Will, B

1990-02-12

In order to assess sensorimotor and/or cognitive modifications following chronic inhibition of nucleus basalis magnocellularis (NBM) neurons, rats trained in two radial maze paradigms (the classical version of the test and a modified version introducing a one-hour delay between the fourth and the fifth choice) received chronic infusion of gamma-aminobutyric acid (GABA) into the NBM area. GABA (10 and 50 micrograms/microliters/h) was infused for 3 days into the NBM contralateral to their preferred turning direction in the radial maze. Simultaneously, saline (NaCl 0.9%; 1 microliter/h) was infused into the contralateral NBM. GABA and saline infusions were alternated for the subsequent 3-day period. One week later, we investigated the rats' ability to learn a multiple trial passive avoidance task. At the dose of 50 micrograms/microliters, GABA infusion produced (1) a turning bias ipsilateral to the side first infused with GABA, (2) transitory cognitive impairments in radial maze tasks and (3) a deficit in the acquisition of the passive avoidance task. At the dose of 10 micrograms/microliters, the same behavioral deficits were observed except that (1) the turning bias was reversed by the contralateral GABA infusion and (2) cognitive impairments in the radial maze were observed only when a delay was inserted between the fourth and the fifth choice. Histologically, we found a dose-dependent gliosis in the NBM area first infused with GABA. These data suggest a reactivity of the NBM to GABAergic manipulations and the intervention of this structure in both sensorimotor and cognitive processes involved in the radial maze paradigms.

Effect of central muscarinic receptors on passive-avoidance learning deficits induced by prenatal pentylenetetrazol kindling in male offspring.

PubMed

Pourmotabbed, A; Mahmoodi, G; Mahmoodi, S; Mohammadi-Farani, A; Nedaei, S E; Pourmotabbed, T; Pourmotabbed, T

2014-10-24

Occurrence of the epileptic seizures during gestation might affect the neurodevelopment of the fetus resulting in cognitive problems for the child later in life. We have previously reported that prenatal pentylenetetrazol (PTZ)-kindling induces learning and memory deficits in the children born to kindled mothers, later in life but the mechanisms involved in this processes are unknown. The cholinergic system plays a major role in learning and memory. The present study was performed to investigate the possible involvement of central muscarinic cholinergic receptors on learning and memory deficits induced by prenatal PTZ-kindling in male offspring. Pregnant Wistar rats were kindled by repetitive i.p. injection of 25mg/kg of PTZ on day 13 of their pregnancy. The effect of intracerebroventricular (ICV) microinjection of scopolamine and pilocarpine, muscarinic cholinergic receptors antagonist and agonist, respectively on passive-avoidance learning of pups were tested at 12weeks of age using shuttle-box apparatus. Our data showed that the retention latencies of pups that received scopolamine (2 or 3μg) were significantly reduced compared to those received normal saline (p<0.05). Interestingly, post training ICV administration of pilocarpine (2μg) retrieved pups' memory deficits (p<0.001). These results demonstrate for the first time, the importance of the central muscarinic cholinergic receptors in learning and memory deficits in pups born to kindled dams and suggest a central mechanism for the cognitive and memory dysfunction, associated with seizures during pregnancy. Copyright © 2014. Published by Elsevier Ltd.

Effect of rat parental morphine exposure on passive avoidance memory and morphine conditioned place preference in male offspring.

PubMed

Akbarabadi, Ardeshir; Niknamfar, Saba; Vousooghi, Nasim; Sadat-Shirazi, Mitra-Sadat; Toolee, Heidar; Zarrindast, Mohammad-Reza

2018-02-01

Drug addiction is a chronic disorder resulted from complex interaction of genetic, environmental, and developmental factors. Epigenetic mechanisms play an important role in the development and maintenance of addiction and also memory formation in the brain. We have examined passive avoidance memory and morphine conditioned place preference (CPP) in the offspring of male and/or female rats with a history of adulthood morphine consumption. Adult male and female animals received chronic oral morphine for 21days and then were maintained drug free for 10days. After that, they were let to mate with either an abstinent or control rat. Male offspring's memory was evaluated by step through test. Besides, rewarding effects of morphine were checked with CCP paradigm. Offspring of abstinent animals showed significant memory impairment compared to the control group which was more prominent in the offspring of abstinent females. Conditioning results showed that administration of a high dose of morphine (10mg/kg) that could significantly induce CPP in control rats, was not able to induce similar results in the offspring of morphine abstinent parents; and CPP was much more prominent when it was induced in the offspring of morphine exposed females compared to the progeny of morphine exposed males. It is concluded that parental morphine consumption in adulthood even before mating has destructive effects on memory state of the male offspring and also leads to tolerance to the rewarding effects of morphine. These effects are greater when the morphine consumer parent is the female one. Copyright © 2017 Elsevier Inc. All rights reserved.

N-Methyl-D-aspartate receptor antagonist MK-801 and radical scavengers protect cholinergic nucleus basalis neurons against beta-amyloid neurotoxicity.

PubMed

Harkany, T; Mulder, J; Sasvári, M; Abrahám, I; Kónya, C; Zarándi, M; Penke, B; Luiten, P G; Nyakas, C

1999-04-01

Previous experimental data indicate the involvement of Ca(2+)-related excitotoxic processes, possibly mediated by N-Methyl-D-Aspartate (NMDA) receptors, in beta-amyloid (beta A) neurotoxicity. On the other hand, other lines of evidence support the view that free radical generation is a critical step in the beta A-induced neurodegenerative cascade. In the present study, therefore, a neuroprotective strategy was applied to explore the contributions of each of these pathways in beta A toxicity. beta A(1-42) was injected into the magnocellular nucleus basalis of rats, while neuroprotection was achieved by either single or combined administration of the NMDA receptor antagonist MK-801 (2.5 mg/kg) and/or a vitamin E and C complex (150 mg/kg). The degree of neurodegeneration was determined by testing the animals in consecutive series of behavioral tasks, including elevated plus maze, passive avoidance learning, small open-field and open-field paradigms, followed by acetylcholinesterase (AChE), choline-acetyltransferase (ChAT), and superoxide dismutase (SOD) biochemistry. beta A injected in the nucleus basalis elicited significant anxiety in the elevated plus maze, derangement of passive avoidance learning, and altered spontaneous behaviors in both open-field tasks. A significant decrease in both AChE and ChAT accompanied by a similar decrement of MnSOD, but not of Cu/ZnSOD provided neurochemical substrates for the behavioral changes. Each of the single drug administrations protected against the neurotoxic events, whereas the combined treatment failed to ameliorate beta A toxicity.

Acute treatment with bis selenide, an organic compound containing the trace element selenium, prevents memory deficits induced by reserpine in rats.

PubMed

Bortolatto, Cristiani Folharini; Guerra Souza, Ana Cristina; Wilhelm, Ethel Antunes; Nogueira, Cristina Wayne

2013-01-01

Taking into account the promising pharmacological actions of (Z)-2,3-bis(4-chlorophenylselanyl) prop-2-en-1-ol) (bis selenide), an organic compound containing the trace element selenium, and the constant search for drugs that improve the cognitive performance, the objective of the present study was to investigate whether bis selenide treatment ameliorates memory deficits induced by reserpine in rats. For this aim, male adult rats received a single subcutaneous injection of reserpine (1 mg/kg), a biogenic amine-depleting agent used to induce memory deficit. After 24 h, bis selenide at doses of 25 and 50 mg/kg was administered to rats by intragastric route, and 1 h later, the animals were submitted to behavior tasks. The effects of acute administration of bis selenide on memory were evaluated by social recognition, step-down passive avoidance, and object recognition paradigms. Exploratory and locomotor activities of rats were determined using the open-field test. Analysis of data revealed that the social memory disruption caused by reserpine was reversed by bis selenide at both doses. In addition, bis selenide, at the highest dose, prevented the memory deficit resulting from reserpine administration to rats in step-down passive avoidance and object recognition tasks. No significant alterations in locomotor and exploratory behaviors were found in animals treated with reserpine and/or bis selenide. Results obtained from distinct memory behavioral paradigms revealed that an acute treatment with bis selenide attenuated memory deficits induced by reserpine in rats.

Paternal and maternal alcohol consumption: effects on offspring in two strains of rats.

PubMed

Abel, E L

1989-08-01

Long-Evans and Sprague-Dawley male rats were given liquid alcohol diets containing 35%, 17.5%, or 0% ethanol-derived calories (EDC). The latter two groups were pair fed to the higher alcohol diet group. A fourth group received lab chow and water ad libitum to assess the role of paternal undernutrition associated with alcohol consumption. After three or four weeks of diet consumption, these males were bred to females of the same strain. Pregnant females were divided into similarly treated alcohol groups and were fed these diets beginning on gestation Day 8, thus creating a factorial study with strain, paternal, and maternal alcohol consumption as main factors. Paternal alcohol consumption was associated with decreased litter size, decreased testosterone levels, and a strain-related effect on offspring activity. Offspring activity decreased for those sired by 35% and 17.5% EDC Long-Evans fathers. Activity also decreased for offspring sired by 17.5% EDC Sprague-Dawley fathers but increased for those sired by 35% EDC fathers. Paternal alcohol consumption did not affect postnatal mortality or passive avoidance learning of offspring. Maternal alcohol consumption was associated with lower birth weights, lower offspring weights at weaning, increased postnatal mortality, and poorer passive avoidance learning. However, offspring activity was not affected. In a separate study, levels of alcohol in the testes were found to be somewhat, but not significantly, lower than blood alcohol levels. DNA taken from sperm of Long-Evans males consuming alcohol, migrated farther under pulsed field electrophoresis than DNA from control fathers, suggestive of an alcohol-related effect on sperm DNA.

Effect of root-extracts of Ficus benghalensis (Banyan) in memory, anxiety, muscle co-ordination and seizure in animal models.

PubMed

Panday, Dipesh Raj; Rauniar, G P

2016-11-03

Ficus benghalensis L. (Banyan) is a commonly found tree in Eastern Nepal. Its different plant parts are used for various neurological ailments. This study was performed in mice to see its effects in various neuropharmacological parameters. Passive-avoidance (memory), Open-field (anxiety), Pentobarbital-induced Sleep potentiation (sleep), Rota-rod (muscle-co-ordination), Pentylenetetrazol-Induced and Maximal Electroshock Seizure Tests were performed. Sample size was calculated using G*Power 3.1.9.2. Aqueous root extracts (Soxhlet method) of Ficus benghalensis 100 mg/kg and 200 mg/kg with negative and positive controls were used. The experimental results were represented as Mean ± SD. P-value was set at <0.05. Oneway analysis of variance (ANOVA) or Mann-Whitney U test was appropriately used. Passive-avoidance test showed 200 mg/kg group spent significantly less. Time (0.00s + 0.00s) in shock-zone than Normal Saline-group (9.67 s + 14.36 s, P = 0.000) or Diazepam-group (41.07 s + 88.24 s, P = 0.000). Open-field test showed 200 mg/kg group spent significantly longer Time (24.77 s + 12.23 s) in central-square than either Normal Saline group (15.08 s + 6.81 s, P = 0.000) or Diazepam-group (15.32 s + 5.12 s, P = 0.000). In Rota-rod test, 200 mg/kg group fell off the rod significantly (P = 0.000) earlier (33.01 s + 43.61 s) than both Normal Saline (>120 s) and Diazepam (62.07 s + 43.83 s) PTZ model showed that 100 mg/kg significantly (P = 0.004) delayed seizure-onset (184.40s + 36.36 s) compared to Normal Saline (101.79 s + 22.81 s), however, in MES model 200 mg/kg significantly (P = 0.000) prolonged tonic hind-limb extension (17.57 s + 2.15 s) compared to Normal Saline (13.55 s + 2.75 s) or Phenytoin (00.00s + 00.00s). Aerial roots of Ficus benghalensis have memory-enhancing, anxiolytic, musclerelaxant, and seizure-modifying effect.

Leadership and Creativity in Higher Education

ERIC Educational Resources Information Center

Zacher, Hannes; Johnson, Emily

2015-01-01

Leadership and creativity have received increasing attention from researchers in the field of higher education; however, empirical studies investigating these topics simultaneously are rare. In this study, the authors examined relationships between PhD students' perceptions of their advising professors' passive-avoidant, transactional, and…

p-Coumaric acid enhances long-term potentiation and recovers scopolamine-induced learning and memory impairments.

PubMed

Kim, Hyun-Bum; Lee, Seok; Hwang, Eun-Sang; Maeng, Sungho; Park, Ji-Ho

2017-10-21

Due to the improvement of medical level, life expectancy increased. But the increased incidence of cognitive disorders is an emerging social problem. Current drugs for dementia treatment can only delay the progress rather than cure. p-Coumaric acid is a phenylpropanoic acid derived from aromatic amino acids and known as a precursor for flavonoids such as resveratrol and naringenin. It was shown to reduce oxidative stress, inhibit genotoxicity and exert neuroprotection. Based on these findings, we evaluated whether p-coumaric acid can protect scopolamine induced learning and memory impairment by measuring LTP in organotypic hippocampal slice and cognitive behaviors in rats. p-Coumaric acid dose-dependently increased the total activity of fEPSP after high frequency stimulation and attenuated scopolamine-induced blockade of fEPSP in the hippocampal CA1 area. In addition, while scopolamine shortened the step-through latency in the passive avoidance test and prolonged the latency as well as reduced the latency in the target quadrant in the Morris water maze test, co-treatment of p-coumaric acid improved avoidance memory and long-term retention of spatial memory in behavioral tests. Since p-coumaric acid improved electrophysiological and cognitive functional deterioration by scopolamine, it may have regulatory effects on central cholinergic synapses and is expected to improve cognitive problems caused by abnormality of the cholinergic nervous system. Copyright © 2017 Elsevier Inc. All rights reserved.

Agmatine attenuates methamphetamine-induced passive avoidance learning and memory and CaMKII-α gene expression deteriorations in hippocampus of rat.

PubMed

Noorbakhshnia, Maryam; Rashidkaboli, Arsham; Pakatchian, Mahnaz; Beheshti, Siamak

2018-06-13

Methamphetamine (METH) abuse is one the most worldwide problems with wide-ranging effects on the central nervous system (CNS). Chronic METH abuse can associate with cognitive abnormalities and neurodegenerative changes in the brain. Agmatine, a cationic polyamine, has been proposed as a neuromodulator that modulates many effects of abused drugs. The aim of this study was to determine if agmatine can decrease the impairment effect of METH on memory and hippocampal CaMKII-α gene expression, a gene that plays a major role in memory. Male wistar rats (200-220 g) were allocated into 7 groups, including 5 groups of saline, METH (1, 2 mg/kg), Agmatine (5, 10 mg/kg) and 2 groups of agmatine (5, 10 mg/kg) with higher doses of METH (2 mg/kg) for 5 consecutive days (n = 8 in each group). All injections were done intraperitoneally and agmatine was administrated 10 min before METH treatment. Furthermore, Passive avoidance learning (PAL) test was assessed on the 5th day. Retention test was done 24 h after training and the rats were sacrificed immediately. Hippocampi were removed and stored at -80 °C. Finally, hippocampal CaMKII-α gene expression was measured using Quantitative Real-time PCR. Our data showed that chronic METH dose-dependently impaired PAL retrieval, as it decreased step-through latency (STL) and increased time spent in the dark compartment (TDC). While Agmatine with a higher dose (10 mg/kg) significantly decreased impairment effect of METH (2 mg/kg) on PAL and memory. Also, molecular results revealed that METH (2 mg/kg) markedly decreased hippocampal CaMKII-α gene expression while agmatine (10 mg/kg) coadminstration prevented it. Taken together, the results propose that agmatine may provide a potential therapy for learning and memory deficits induced by METH. Copyright © 2017. Published by Elsevier Inc.

Spatial learning in the genetically heterogeneous NIH-HS rat stock and RLA-I/RHA-I rats: revisiting the relationship with unconditioned and conditioned anxiety.

PubMed

Martínez-Membrives, Esther; López-Aumatell, Regina; Blázquez, Gloria; Cañete, Toni; Tobeña, Adolf; Fernández-Teruel, Alberto

2015-05-15

To characterize learning/memory profiles for the first time in the genetically heterogeneous NIH-HS rat stock, and to examine whether these are associated with anxiety, we evaluated NIH-HS rats for spatial learning/memory in the Morris water maze (MWM) and in the following anxiety/fear tests: the elevated zero-maze (ZM; unconditioned anxiety), a context-conditioned fear test and the acquisition of two-way active avoidance (conditioned anxiety). NIH-HS rats were compared with the Roman High- (RHA-I) and Low-Avoidance (RLA-I) rat strains, given the well-known differences between the Roman strains/lines in anxiety-related behavior and in spatial learning/memory. The results show that: (i) As expected, RLA-I rats were more anxious in the ZM test, displayed more frequent context-conditioned freezing episodes and fewer avoidances than RHA-I rats. (ii) Scores of NIH-HS rats in these tests/tasks mostly fell in between those of the Roman rat strains, and were usually closer to the values of the RLA-I strain. (iii) Pigmented NIH-HS (only a small part of NIH-HS rats were albino) rats were the best spatial learners and displayed better spatial memory than the other three (RHA-I, RLA-I and NIH-HS albino) groups. (iv) Albino NIH-HS and RLA-I rats also showed better learning/memory than the RHA-I strain. (v) Within the NIH-HS stock, the most anxious rats in the ZM test presented the best learning and/or memory efficiency (regardless of pigmentation). In summary, NIH-HS rats display a high performance in spatial learning/memory tasks and a passive coping strategy when facing conditioned conflict situations. In addition, unconditioned anxiety in NIH-HS rats predicts better spatial learning/memory. Copyright © 2015 Elsevier Inc. All rights reserved.

Avoiding superior tilt in reverse shoulder arthroplasty: a review of the literature and technical recommendations.

PubMed

Laver, Lior; Garrigues, Grant E

2014-10-01

Superior tilt of the baseplate component in reverse total shoulder arthroplasty leads to tensile baseplate forces and may be a contributor to early loosening. The risk factors for this implant malposition include inadequate exposure through a superior approach and superior glenoid bone deficiency that obscures the native glenoid tilt. Here we review our preoperative evaluation and surgical management strategies to avoid superior tilt. Adequate exposure with a superior approach can be achieved but requires not just proper surgical technique but also careful patient selection. We propose that the superior approach be considered only for acute proximal humerus fractures or in patients when the following criteria are met: no prior open surgery on the shoulder; more than 30° of passive external rotation at 0° of abduction; no medial humeral osteophytes; and any superior migration must be reducible with a sulcus test during examination under anesthesia. Avoiding superior tilt when there is significant superior glenoid erosion can be accomplished with humeral head autograft, most easily performed through a deltopectoral approach. Preoperative templating is critical to determine proper graft thickness, inclination, reaming depth, and harvest technique. Copyright © 2014 Journal of Shoulder and Elbow Surgery Board of Trustees. Published by Elsevier Inc. All rights reserved.

Long-term moderate treadmill exercise promotes stress-coping strategies in male and female rats.

PubMed

Lalanza, Jaume F; Sanchez-Roige, Sandra; Cigarroa, Igor; Gagliano, Humberto; Fuentes, Silvia; Armario, Antonio; Capdevila, Lluís; Escorihuela, Rosa M

2015-11-05

Recent evidence has revealed the impact of exercise in alleviating anxiety and mood disorders; however, the exercise protocol that exerts such benefit is far from known. The current study was aimed to assess the effects of long-term moderate exercise on behavioural coping strategies (active vs. passive) and Hypothalamic-Pituitary-Adrenal response in rats. Sprague-Dawley male and female rats were exposed to 32-weeks of treadmill exercise and then tested for two-way active avoidance learning (shuttle-box). Two groups were used as controls: a non-handled sedentary group, receiving no manipulation, and a control group exposed to a stationary treadmill. Female rats displayed shorter escape responses and higher number of avoidance responses, reaching criterion for performance earlier than male rats. In both sexes, exercise shortened escape latencies, increased the total number of avoidances and diminished the number of trials needed to reach criterion for performance. Those effects were greater during acquisition in female rats, but remained over the shuttle-box sessions in treadmill trained male rats. In females, exercise did not change ACTH and corticosterone levels after shuttle-box acquisition. Collectively, treadmill exercise improved active coping strategies in a sex-dependent manner. In a broader context, moderate exercise could serve as a therapeutic intervention for anxiety and mood disorders.

Long-term moderate treadmill exercise promotes stress-coping strategies in male and female rats

PubMed Central

Lalanza, Jaume F.; Sanchez-Roige, Sandra; Cigarroa, Igor; Gagliano, Humberto; Fuentes, Silvia; Armario, Antonio; Capdevila, Lluís; Escorihuela, Rosa M.

2015-01-01

Recent evidence has revealed the impact of exercise in alleviating anxiety and mood disorders; however, the exercise protocol that exerts such benefit is far from known. The current study was aimed to assess the effects of long-term moderate exercise on behavioural coping strategies (active vs. passive) and Hypothalamic-Pituitary-Adrenal response in rats. Sprague-Dawley male and female rats were exposed to 32-weeks of treadmill exercise and then tested for two-way active avoidance learning (shuttle-box). Two groups were used as controls: a non-handled sedentary group, receiving no manipulation, and a control group exposed to a stationary treadmill. Female rats displayed shorter escape responses and higher number of avoidance responses, reaching criterion for performance earlier than male rats. In both sexes, exercise shortened escape latencies, increased the total number of avoidances and diminished the number of trials needed to reach criterion for performance. Those effects were greater during acquisition in female rats, but remained over the shuttle-box sessions in treadmill trained male rats. In females, exercise did not change ACTH and corticosterone levels after shuttle-box acquisition. Collectively, treadmill exercise improved active coping strategies in a sex-dependent manner. In a broader context, moderate exercise could serve as a therapeutic intervention for anxiety and mood disorders. PMID:26538081

Extensibility of the hamstrings is best explained by mechanical components of muscle contraction, not behavioral measures in individuals with chronic low back pain.

PubMed

Marshall, Paul W M; Mannion, Jamie; Murphy, Bernadette A

2009-08-01

To examine the relationship between hamstring extensibility by use of the instrumented straight leg raise; mechanical components of muscle contraction, including muscle recruitment, passive torque measures of tissue stiffness, and eccentric strength; and self-reported measures of pain and disability. Cross-sectional study. University laboratory. Twenty-one individuals with chronic nonspecific axial lower back pain and 15 healthy control subjects. Instrumented straight leg raise, concentric and eccentric hamstring strength, self-reported measures of pain, disability, fear avoidance, general health and well-being Objective measures included hamstring extensibility, hamstring muscle stiffness, absolute and relative concentric/eccentric strength, concentric/eccentric strength ratios. Self-reported measures included Oswestry disability index, visual analog pain scale, fear avoidance beliefs, and general health and well being. Patients with lower back pain had lower range of motion, greater changes in muscle stiffness, and impaired concentric-to-eccentric strength levels. Stepwise regression identified measures of stiffness as significantly predicting hamstring extensibility (adjusted r(2) = 0.58, F = 23.76, P < .001). Self-reported measures were not associated with extensibility. Gender differences were noted for passive stiffness and absolute strength. For women, later onset of the medial hamstrings also was associated with greater hamstring extensibility. Decreased extensibility of the hamstrings was associated with increased passive stiffness during the common range of motion (20 to 50 degrees ). Impaired stretch tolerance is associated with actual mechanical restriction, not behavioral measures indicating increased pain or fear-avoidant behavior. With no relationship to actual disability and contradictory findings in the literature for the relationship of the hamstrings to the mechanics of the low back, it is unclear whether decreased hamstring extensibility should be targeted in rehabilitation programs for axial lower back pain.

Summary of avoidable cancers in the Nordic countries.

PubMed

Olsen, J H; Andersen, A; Dreyer, L; Pukkala, E; Tryggvadottir, L; Gerhardsson de Verdier, M; Winther, J F

1997-01-01

An overview is given of the most important known causes of cancer in the five Nordic countries and the resulting number of cancers that are potentially avoidable. The main causes include active and passive smoking, alcohol consumption, exposure to asbestos and other occupational carcinogens, solar and ionizing radiation, obesity, human papillomavirus infection in the female genital tract and infection with Helicobacter pylori. The organs most commonly affected are those of the respiratory system, the upper digestive tract and stomach, skin, the lower urinary tract and the uterine cervix. Annually, more than 18,000 cancers in men and 11,000 in women in the Nordic populations could be avoided by eliminating exposure to known carcinogens which is equivalent to 33% and 20% of all cancers arising in men and women, respectively, around the year 2000. Smoking habits account for a little more than half of these avoidable cases. Estimates of avoidable cancers are given for each Nordic country, separately.

Place avoidance learning and memory in a jumping spider.

PubMed

Peckmezian, Tina; Taylor, Phillip W

2017-03-01

Using a conditioned passive place avoidance paradigm, we investigated the relative importance of three experimental parameters on learning and memory in a salticid, Servaea incana. Spiders encountered an aversive electric shock stimulus paired with one side of a two-sided arena. Our three parameters were the ecological relevance of the visual stimulus, the time interval between trials and the time interval before test. We paired electric shock with either a black or white visual stimulus, as prior studies in our laboratory have demonstrated that S. incana prefer dark 'safe' regions to light ones. We additionally evaluated the influence of two temporal features (time interval between trials and time interval before test) on learning and memory. Spiders exposed to the shock stimulus learned to associate shock with the visual background cue, but the extent to which they did so was dependent on which visual stimulus was present and the time interval between trials. Spiders trained with a long interval between trials (24 h) maintained performance throughout training, whereas spiders trained with a short interval (10 min) maintained performance only when the safe side was black. When the safe side was white, performance worsened steadily over time. There was no difference between spiders tested after a short (10 min) or long (24 h) interval before test. These results suggest that the ecological relevance of the stimuli used and the duration of the interval between trials can influence learning and memory in jumping spiders.

THE EFFECT OF INTIMACY AND STATUS DISCREPANCY ON SALIENT AND NON-SALIENT CONFLICT STRATEGIES OF JAPANESE.

PubMed

Nakatsugawa, Satomi; Takai, Jiro

2015-10-01

It has been claimed that Japanese people prefer passive forms of conflict strategies to preserve interpersonal harmony. This study aimed to identify some conditions in which such passive strategies are used. The effects of target intimacy and status discrepancy on the intent and use of salient and non-salient conflict strategies were examined, along with respondent sex differences. Questionnaires were collected from 205 Japanese university students. Results indicated that women were more likely to have non-salient intents than men and that intimacy affected considerateness intent but not avoidance intent. Active non-salient strategy was affected by status while passive non-salient strategy was affected by intimacy. Overall, target characteristics proved to be a strong factor in the intents and strategies employed in conflict situations of Japanese.

Instant loading with intraoral welding technique and PRAMA implants: a new prosthetic approach.

PubMed

Celletti, R; Fanali, S; Laici, C U; Santori, C; Pignatelli, P; Sinjari, B

2017-01-01

When splinting multiple implants passive fit of the framework should be achieved to avoid excessive force distribution on the implants. Recently, a protocol was suggested for immediate loading of multiple implants by welding a titanium bar to implant abutments directly in the oral cavity so as to create a customized, precise and passive metal-reinforced provisional restoration. The intraoral welding technique subsequently proves to be a successful option in the full-arch immediate restorations of the mandible and maxilla. The aim of this article is to present a case report in which a new prosthetic approach, using trans-mucosal implants, is described. Dental implants are instantly loaded with a provisional prosthesis supported by an intraoral welded titanium framework to obtain a precise passive fit of the immediate loaded prosthesis.

Gypenosides ameliorate memory deficits in MPTP-lesioned mouse model of Parkinson's disease treated with L-DOPA.

PubMed

Zhao, Ting Ting; Kim, Kyung Sook; Shin, Keon Sung; Park, Hyun Jin; Kim, Hyun Jeong; Lee, Kyung Eun; Lee, Myung Koo

2017-09-06

Previous studies have revealed that gypenosides (GPS) improve the symptoms of anxiety disorders in a 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP)-lesioned rat model of Parkinson's disease (PD). The present study aimed to investigate the effects of GPS on memory deficits in an MPTP-lesioned mouse model of PD treated with L-3,4-dihydroxyphenylalanine (L-DOPA). MPTP (30 mg/kg/day, 5 days)-lesioned mice were treated with GPS (50 mg/kg) and/or L-DOPA (10 and 25 mg/kg) for 21 days. After the final treatments, behavioral changes were assessed in all mice using passive avoidance and elevated plus-maze tests. We then evaluated the biochemical influences of GPS treatment on levels of tyrosine hydroxylase (TH), dopamine, N-methyl-D-aspartate (NMDA) receptors, extracellular signal-regulated kinase (ERK1/2), and cyclic AMP-response element binding protein (CREB) phosphorylation. MPTP-lesioned mice exhibited deficits associated with habit learning and spatial memory, which were further aggravated by treatment with L-DOPA (25 mg/kg). However, treatment with GPS (50 mg/kg) ameliorated memory deficits. Treatment with GPS (50 mg/kg) also improved L-DOPA (25 mg/kg)-treated MPTP lesion-induced decreases in retention latency on the passive avoidance test, as well as levels of TH-immunopositive cells and dopamine in the substantia nigra and striatum. GPS treatment also attenuated increases in retention transfer latency on the elevated plus-maze test and in NMDA receptor expression, as well as decreases in the phosphorylation of ERK1/2 and CREB in the hippocampus. Treatment with L-DOPA (10 mg/kg) also ameliorated deficits in habit learning and spatial memory in MPTP-lesioned mice, and this effect was further enhanced by treatment with GPS (50 mg/kg). GPS ameliorate deficits in habit learning and spatial memory by modulating the dopaminergic neuronal and N-methyl-D-aspartate receptor-mediated signaling systems in MPTP-lesioned mice treated with L-DOPA. GPS may serve as an adjuvant therapeutic agent for memory deficits in patients with PD receiving L-DOPA.

Evaluation of Non-Chromate Passivations on Electroplated gamma-Phase Zinc Nickel

NASA Astrophysics Data System (ADS)

Volz, Steven Michael

This research focused on the corrosion response and electrochemical behavior of electroplated low hydrogen embrittlement alkaline gamma-phase zinc nickel with passivation layers. The motivation was the need to replace hexavalent chromium conversion coatings in military grade electrical systems with a more environment friendly alternative. The passivation layers were employed for the purpose of mitigating corrosion attack while maintaining low contact resistance. Trivalent chromium-based passivations and cerium-based passivations were compared against the currently used hexavalent chromium conversion coating. The coating systems were compared using electrochemical impedance spectroscopy, cyclic potentiodymanic scans, salt spray exposure testing, electrical resistance measurements, microstructure analysis, and compositional analysis. Coating systems with lower open circuit had a lower corrosion current and performed better during salt spray testing. All of the systems evaluated had corrosion products consistent with oxidized zinc compounds but the morphology of the passivation was dependent on the passivation. The electrical contact resistance ranged from 1 to 108 mO/cm 2, after salt spray testing. Two versions of Trivalent chromium-based passivations, were able to meet military performance specifications after corrosion testing.

Excess weight, arterial pressure and physical activity in commuting to school: correlations.

PubMed

Silva, Kelly S; Lopes, Adair S

2008-08-01

The prevalence of obesity and elevated arterial pressure (AP) has increased in children and adolescents, whereas physical activity has decreased. To identify and correlate excess weight, body fat and elevated AP among active and passive students with the way they commute to school. One thousand five hundred and seventy students aged 7 to 12 years participated in the study conducted in João Pessoa, state of Paraíba. Students completed a questionnaire about the way they commuted to school (active = walking/biking or passive = by car/motorcycle/bus) and the time spent traveling to school. Excess weight was determined by BMI > or =25 kg/m(2), excess body fat as > or =85th percentile for tricipital fold measurement, and high AP as > or =90th percentile. Chi-square test and Poisson's regression were used for the analysis. Active commuting was associated with a lower prevalence of excess weight and body fat as compared to passive commuting (p<0.05). The prevalence ratio (PR) of excess weight was associated with excess body fat (Male: PR= 6.45 95%CI= 4.55-9.14; Female: PR= 4.10 95%CI= 3.09-5.45), elevated SAP [Systolic Arterial Pressure] (Male: PR= 1.99 95%CI= 1.30-3.06; Female: PR= 2.09 95%CI= 1.45-3.01), and elevated DAP [Diastolic Arterial Pressure] in girls (PR = 1.96 95%CI= 1.41-2.75). No association with active commuting was observed (p>0.05) Passive commuting to school showed a correlation with excess weight and body fat but not with elevated AP. Excess weight was associated with excessive body fat and elevated AP. Excess weight should be prevented as a way to avoid fat accumulation and AP elevation.

Interrelationship of Personality Disorders: Theoretical Formulations and Anecdotal Evidence.

ERIC Educational Resources Information Center

Vincent, Ken R.

1987-01-01

Attempts to define interrelationship of personality disorders. Discusses relationships between and among three major groupings of Diagnostic and Statistical Manual of Mental Disorders. Suggests that passive aggressive, avoidant, and borderline personality disorders serve as bridges between these groupings. Discusses placement within groupings with…

Pre-electroconvulsive shock administration of calcium channel blockers reduces retrograde amnesia induced by ECS.

PubMed

Sushma, M; Sudha, S; Guido, S

2004-11-01

Effect of pre-electroconvulsive shock (ECS) administration of calcium channel blockers (CCBs) like verapamil, diltiazem, nifedipine, nimodipine, flunarizine and cinnarizine on retrograde amnesia induced by ECS was examined using passive avoidance paradigm in rats. The groups (Gr 1-7) of adult, male Wistar rats received true ECS with CCBs (5mg/kg; i.p) or vehicle (10 ml/kg; ip) and other groups (Gr 8-14) received sham ECS with CCBs (5mg/kg; i.p) or vehicle (10 ml/kg; i.p). The anti-amnestic activity of CCBs were evaluated using the passive avoidance paradigm in rats. Results showed that, the baseline latencies for all the groups did not differ significantly. Rats receiving true ECS produced significantly lower latencies. There was increase in the post ECS step through latencies of the rats administered CCBs before ECS. Therefore, pre-ECS administration of calcium channel blockers might reduce retrograde amnesia produced by ECS without altering seizure duration.

[Effect of agonist and antagonist of 5-HT(1A) receptors on learning in female rats during ovarian cycle].

PubMed

Fedotova, Iu O; Ordian, N E

2010-01-01

The involvement of 5-HT(1A) receptors in learning/memory processes during ovary cycle was assessed in the adult female rats. 8-OH-DPAT (0.05 mg/kg, s.c.), 5-HT(1A) receptor agonist and NAN-190 (0.1 mg/kg, i.p.), 5-HT(1A) receptor antagonist were injected chronically to adult female rats. Learning of these animals was assessed in different models: passive avoidance performance and Morris water maze. Chronic NAN-190 administration to females resulted in the appearance of the passive avoidance performance in proestrous and estrous, as distinct from the control animals, but failed to change the dynamics of spatial learning in Morris water maze. Chronic 8-OH-DPAT administration similarly impaired non-spatial and spatial learning in females during all phases of ovary cycle. The results of the study suggest modulating role of 5-HT(1A) receptors in learning/memory processes during ovary cycle in the adult female rats.

Furoxans (Oxadiazole-4 N-oxides) with Attenuated Reactivity are Neuroprotective, Cross the Blood Brain Barrier, and Improve Passive Avoidance Memory.

PubMed

Horton, Austin; Nash, Kevin; Tackie-Yarboi, Ethel; Kostrevski, Alexander; Novak, Adam; Raghavan, Aparna; Tulsulkar, Jatin; Alhadidi, Qasim; Wamer, Nathan; Langenderfer, Bryn; Royster, Kalee; Ducharme, Maxwell; Hagood, Katelyn; Post, Megan; Shah, Zahoor A; Schiefer, Isaac T

2018-05-07

Nitric oxide (NO) mimetics and other agents capable of enhancing NO/cGMP signaling have demonstrated efficacy as potential therapies for Alzheimer's disease. A group of thiol-dependent NO mimetics known as furoxans may be designed to exhibit attenuated reactivity to provide slow onset NO effects. The present study describes the design, synthesis, and evaluation of a furoxan library resulting in the identification of a prototype furoxan, 5a, which was profiled for use in the central nervous system. Furoxan 5a demonstrated negligible reactivity toward generic cellular thiols under physiological conditions. Nonetheless, cGMP-dependent neuroprotection was observed, and 5a (20 mg/kg) reversed cholinergic memory deficits in a mouse model of passive avoidance fear memory. Importantly, 5a can be prepared as a pharmaceutically acceptable salt and is observed in the brain 12 h after oral administration, suggesting potential for daily dosing and excellent metabolic stability. Continued investigation into furoxans as attenuated NO mimetics for the CNS is warranted.

Coping strategies for HIV-related stigma in Liuzhou, China.

PubMed

Zhang, Ying-Xia; Ying-Xia, Zhang; Golin, Carol E; Bu, Jin; Jin, Bu; Emrick, Catherine Boland; Nan, Zhang; Li, Ming-Qiang; Ming-Qiang, Li

2014-02-01

This study explores the feelings, experiences, and coping strategies of people living with HIV (PLHIV) in Liuzhou, China. In a southwestern Chinese city with high HIV prevalence, we conducted semi-structured in-depth interviews with 47 PLHIV selected to represent individuals who had acquired HIV via different acquisition routes. Many participants felt severely stigmatized; they commonly reported having very low self-esteem and feelings of despair. Based on style of coping and whether it occurred at the interpersonal or intrapersonal level, four types of coping that participants used to deal with HIV-associated stigma were identified: (1) Compassion (Passive/Avoidant-Interpersonal); (2) Hiding HIV status (Passive/Avoidant-Intrapersonal); (3) Social support (Active/Problem-focused-Interpersonal; and (4) Self-care (Active/Problem-focused-Intrapersonal). Educational and stigma-reduction interventions targeting potential social support networks for PLHIV (e.g., family, close friends, and peers) could strengthen active interpersonal PLHIV coping strategies. Interventions teaching self-care to PLHIV would encourage active intrapersonal coping, both of which may enhance PLHIV quality of life in Liuzhou, China.

Effects of activation and blockade of dopamine receptors on the extinction of a passive avoidance reaction in mice with a depressive-like state.

PubMed

Dubrovina, N I; Zinov'eva, D V

2010-01-01

Learning and extinction of a conditioned passive avoidance reaction resulting from neuropharmacological actions on dopamine D(1) and D(2) receptors were demonstrated to be specific in intact mice and in mice with a depressive-like state. Learning was degraded only after administration of the D(2) receptor antagonist sulpiride and was independent of the initial functional state of the mice. In intact mice, activation of D(2) receptors with quinpirole led to a deficit of extinction, consisting of a reduction in the ability to acquire new inhibitory learning in conditions associated with the disappearance of the expected punishment. In mice with the "behavioral despair" reaction, characterized by delayed extinction, activation of D(1) receptors with SKF38393 normalized this process, while the D(2) agonist was ineffective. A positive effect consisting of accelerated extinction of the memory of fear of the dark ("dangerous") sector of the experimental chamber was also seen on blockade of both types of dopamine receptor.

Cannabis sativa allergy: looking through the fog.

PubMed

Decuyper, I I; Van Gasse, A L; Cop, N; Sabato, V; Faber, M A; Mertens, C; Bridts, C H; Hagendorens, M M; De Clerck, L; Rihs, H P; Ebo, D G

2017-02-01

IgE-mediated Cannabis (C. sativa, marihuana) allergy seems to be on the rise. Both active and passive exposure to cannabis allergens may trigger a C. sativa sensitization and/or allergy. The clinical presentation of a C. sativa allergy varies from mild to life-threatening reactions and often seems to depend on the route of exposure. In addition, sensitization to cannabis allergens can result in various cross-allergies, mostly for plant foods. This clinical entity, designated as the 'cannabis-fruit/vegetable syndrome', might also imply cross-reactivity with tobacco, natural latex and plant-food-derived alcoholic beverages. Hitherto, these cross-allergies are predominantly reported in Europe and appear mainly to rely upon cross-reactivity between nonspecific lipid transfer proteins or thaumatin-like proteins present in C. sativa and their homologues, ubiquitously distributed throughout plant kingdom. At present, diagnosis of cannabis-related allergies predominantly rests upon a thorough history completed with skin testing using native extracts from crushed buds and leaves. However, quantification of specific IgE antibodies and basophil activation tests can also be helpful to establish correct diagnosis. In the absence of a cure, treatment comprises absolute avoidance measures. Whether avoidance of further use will halt the extension of related cross-allergies remains uncertain. © 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

[Nootropic and analgesic effects of Semax following different routes of administration].

PubMed

Manchenko, D M; Glazova, N Iu; Levitskaia, N G; Andreeva, L A; Kamenskiĭ, A A; Miasoedov, N F

2010-10-01

Heptapeptide Semax (MEHFPGP) is the fragment of ACTH(4-10) analogue with prolonged neurotropic activity. The aim of the present work was to study the Semax effects on learning capability and pain sensitivity in white rats following intraperitoneal and intranasal administration in different doses. Semax nootropic effects were studied in the test of acquisition of passive avoidance task. Pain sensitivity was estimated in Randall-Selitto paw-withdrawal test. It was shown that Semax exerts nootropic and analgesic activities following intraperitoneal administration. Analysis of dependence of these effects on dose resulted in different dose-response curves. Following intranasal administration, Semax was more potent in learning improvement compared to intraperitoneal administration. The peptide failed to affect the animal pain sensitivity following intranasal administration as opposed to intraperitoneal administration. The data obtained suggest different mechanisms and brain structures involved in realization of the nootropic and analgesic effects of Semax.

Decursin from Angelica gigas mitigates amnesia induced by scopolamine in mice.

PubMed

Kang, So Young; Lee, Ki Yong; Park, Mi Jung; Kim, Young Chul; Markelonis, George J; Oh, Tae H; Kim, Young Choong

2003-01-01

We previously reported that a total methanolic extract of the underground part of Angelica gigas Nakai (Umbelliferae) (here-in-after abbreviated AG) significantly inhibited acetylcholinesterase (AChE) activity. We characterized 12 coumarin derivatives including both decursin and decursinol from extracts of AG. In this study, we evaluated the anti-amnestic activity of decursin, a major coumarin constituent isolated from AG, in vivo using ICR mice with amnesia induced by scopolamine (1 mg/kg body weight, s.c.). Decursin, when administered to mice at 1 and 5 mg/kg body weight i.p., significantly ameliorated scopolamine-induced amnesia as measured in both the passive avoidance test and the Morris water maze test. Moreover, decursin significantly inhibited AChE activity by 34% in the hippocampus of treated mice. These results indicate that decursin may exert anti-amnestic activity in vivo through inhibition of AChE activity in the hippocampus.

Arctigenin isolated from the seeds of Arctium lappa ameliorates memory deficits in mice.

PubMed

Lee, In-Ah; Joh, Eun-Ha; Kim, Dong-Hyun

2011-09-01

The seeds of Arctium lappa L. (AL, family Asteraceae), the main constituents of which are arctiin and arctigenin, have been used as an herbal medicine or functional food to treat inflammatory diseases. These main constituents were shown to inhibit acetylcholinesterase (AChE) activity. Arctigenin more potently inhibited AChE activity than arctiin. Arctigenin at doses of 30 and 60 mg/kg (p. o.) potently reversed scopolamine-induced memory deficits by 62 % and 73 %, respectively, in a passive avoidance test. This finding is comparable with that of tacrine (10 mg/kg p. o.). Arctigenin also significantly reversed scopolamine-induced memory deficits in the Y-maze and Morris water maze tests. On the basis of these findings, arctigenin may ameliorate memory deficits by inhibiting AChE. © Georg Thieme Verlag KG Stuttgart · New York.

Reactive Collision Avoidance Algorithm

NASA Technical Reports Server (NTRS)

Scharf, Daniel; Acikmese, Behcet; Ploen, Scott; Hadaegh, Fred

2010-01-01

The reactive collision avoidance (RCA) algorithm allows a spacecraft to find a fuel-optimal trajectory for avoiding an arbitrary number of colliding spacecraft in real time while accounting for acceleration limits. In addition to spacecraft, the technology can be used for vehicles that can accelerate in any direction, such as helicopters and submersibles. In contrast to existing, passive algorithms that simultaneously design trajectories for a cluster of vehicles working to achieve a common goal, RCA is implemented onboard spacecraft only when an imminent collision is detected, and then plans a collision avoidance maneuver for only that host vehicle, thus preventing a collision in an off-nominal situation for which passive algorithms cannot. An example scenario for such a situation might be when a spacecraft in the cluster is approaching another one, but enters safe mode and begins to drift. Functionally, the RCA detects colliding spacecraft, plans an evasion trajectory by solving the Evasion Trajectory Problem (ETP), and then recovers after the collision is avoided. A direct optimization approach was used to develop the algorithm so it can run in real time. In this innovation, a parameterized class of avoidance trajectories is specified, and then the optimal trajectory is found by searching over the parameters. The class of trajectories is selected as bang-off-bang as motivated by optimal control theory. That is, an avoiding spacecraft first applies full acceleration in a constant direction, then coasts, and finally applies full acceleration to stop. The parameter optimization problem can be solved offline and stored as a look-up table of values. Using a look-up table allows the algorithm to run in real time. Given a colliding spacecraft, the properties of the collision geometry serve as indices of the look-up table that gives the optimal trajectory. For multiple colliding spacecraft, the set of trajectories that avoid all spacecraft is rapidly searched on-line. The optimal avoidance trajectory is implemented as a receding-horizon model predictive control law. Therefore, at each time step, the optimal avoidance trajectory is found and the first time step of its acceleration is applied. At the next time step of the control computer, the problem is re-solved and the new first time step is again applied. This continual updating allows the RCA algorithm to adapt to a colliding spacecraft that is making erratic course changes.

Fear of movement, passive coping, manual handling, and severe or radiating pain increase the likelihood of sick leave due to low back pain.

PubMed

Dawson, Anna P; Schluter, Philip J; Hodges, Paul W; Stewart, Simon; Turner, Catherine

2011-07-01

Sick leave due to low back pain (LBP-SL) is costly and compromises workforce productivity. The fear-avoidance model asserts that maladaptive pain-related cognitions lead to avoidance and disuse, which can perpetuate ongoing pain. Staying home from work is an avoidant behavior, and hence pain-related psychological features may help explain LBP-SL. We examined the relative contribution of pain catastrophizing, fear of movement, and pain coping (active and passive) in LBP-SL in addition to pain characteristics and other psychosocial, occupational, general health, and demographic factors. Two-way interactions between age and gender and candidate exposures were also considered. Our sample comprised 2164 working nurses and midwives with low back pain in the preceding year. Binary logistic regression was performed on cross-sectional data by manual backward stepwise elimination of nonsignificant terms to generate a parsimonious multivariable model. From an extensive array of exposures assessed, fear of movement (women, odds ratio [OR]=1.05, 95% confidence interval [CI] 1.02-1.08; men, OR=1.17, 95% CI 1.05-1.29), passive coping (OR=1.07, 95% CI 1.04-1.11), pain severity (OR=1.61, 95% CI 1.50-1.72), pain radiation (women, OR=1.45, 95% CI 1.10-1.92; men, OR=4.13, 95% CI 2.15-7.95), and manual handling frequency (OR=1.03, 95% CI 1.01-1.05) increased the likelihood of LBP-SL in the preceding 12 months. Administrators and managers were less likely to report LBP-SL (OR=0.44, 95% CI 0.27-0.71), and age had a protective effect in individuals in a married or de facto relationship (OR=0.97, 95% CI 0.95-0.98). In summary, fear of movement, passive coping, frequent manual handling, and severe or radiating pain increase the likelihood of LBP-SL. Gender-specific responses to pain radiation and fear of movement are evident. Crown Copyright © 2011. Published by Elsevier B.V. All rights reserved.

[Euthanasia and the doctrine of double effect].

PubMed

Klein, Martin

2005-01-01

Direct active euthanasia is prohibited in most countries while passive and indirect is not. However, many arguments against the legalization of voluntary active euthanasia are flawed. Ethical differences between active and passive or indirect euthanasia are difficult to maintain especially when the passivity of the actor causes death. The crucial point is not activity or passivity but respect for the autonomy of individual human beings. In particular there appears to be little ethical difference between active and indirect euthanasia. Indirect euthanasia has often been justified by the principle of double effect, which traces back to Thomas Aquinas. But resorting to this rule contains a logical fallacy. The principle of double effect does not allow foreseen and unwanted adverse effects of an action to occur when they are avoidable. In terminal sedation, an example for indirect euthanasia, hypoxemia and dehydration can easily be prevented by respirator therapy and fluid administration. Therefore the rule of double effect is not applicable. Indirect and direct active euthanasia cannot be ethically distinguished by resorting to the principle of double effect.

A low timing jitter picosecond microchip laser pumped by pulsed LD

NASA Astrophysics Data System (ADS)

Wang, Sha; Wang, Yan-biao; Feng, Guoying; Zhou, Shou-huan

2016-07-01

SESAM passively Q-switched microchip laser is a very promising instrument to replace mode locked lasers to obtain picosecond pulses. The biggest drawback of a passively Q-switched microchip laser is its un-avoided large timing jitter, especially when the pump intensity is low, i.e. at low laser repetition rate range. In order to obtain a low timing jitter passively Q-switched picosecond microchip laser in the whole laser repetition rate range, a 1000 kHz pulsed narrow bandwidth Fiber Bragg Grating (FBG) stablized laser diode was used as the pump source. By tuning the pump intensity, we could control the output laser frequency. In this way, we achieved a very low timing jitter passively Q-switched picosecond laser at 2.13 mW, 111.1 kHz. The relative timing jitter was only 0.0315%, which was around 100 times smaller compared with a cw LD pumped microchip working at hundred kilohertz repetition rate frequency range.

Independent learning: a self-instructional videotape approach in psychiatry.

PubMed

Golden, K; Furst, E; Sundermann, R; Delk, J; McGill, S

1980-01-01

In response to the increased need to train well-rounded general practitioners within a limited time schedule, the teaching staff developed a self-instructional videotape programme devoted to suicide assessment. This tape, if successful, was to serve as a pilot for a full series of 18 tapes devoted to the assessment and treatment of normally stable patients suffering acute situational stress. In order to avoid the passivity induced by most educational tapes and films, a self-instructional format was adapted to the videotape medium and extensively tested. Students in the experimental group scored significantly higher on three of four measures of effectiveness than did the control group. Students and teachers both strongly supported the production of tapes using a similar format.

Theoretical and experimental investigation of position-controlled semi-active friction damper for seismic structures

NASA Astrophysics Data System (ADS)

Lu, Lyan-Ywan; Lin, Tzu-Kang; Jheng, Rong-Jie; Wu, Hsin-Hsien

2018-01-01

A semi-active friction damper (SAFD) can be employed for the seismic protection of structural systems. The effectiveness of an SAFD in absorbing seismic energy is usually superior to that of its passive counterpart, since its slip force can be altered in real time according to structural response and excitation. Most existing SAFDs are controlled by adjusting the clamping force applied on the friction interface. Thus, the implementation of SAFDs in practice requires precision control of the clamping force, which is usually substantially larger than the slip force. This may increase the implementation complexity and cost of SAFDs. To avoid this problem, this study proposes a novel position-controlled SAFD, named the leverage-type controllable friction damper (LCFD). The LCFD system combines a traditional passive friction damper and a leverage mechanism with a movable central pivot. By simply controlling the pivot position, the damping force generated by the LCFD system can be adjusted in real time. In order to verify the feasibility of the proposed SAFD, a prototype LCFD was tested by using a shaking table. The test results demonstrate that the equivalent friction force and hysteresis loop of the LCFD can be regulated by controlling the pivot position. By considering 16 ground motions with two different intensities, the adaptive feature of the LCFD for seismic structural control is further demonstrated numerically.

Problems of test choice and data analysis in behavioral teratology: the case of prenatal benzodiazepines.

PubMed

Chiarotti, F; Alleva, E; Bignami, G

1987-01-01

Higher-tier tests for the assessment of early treatment effects should be aimed at providing specific information on the behavior processes affected, rather than simply at extending the descriptive data base. The contrast between positive and negative results can be useful to point out possible mechanisms of action. For example, late prenatal oxazepam exposure of mice produced a reduction of the amphetamine hyperactivity at the end of the second postnatal week, but did not significantly affect the response to scopolamine at the end of the third week. An impairment of active locomotor avoidance was observed at the young adult stage, which contrasted with the absence or scarcity of changes in passive avoidance and extinction responding in the same go-no go tests. These changes in response-activating mechanisms appear to be in agreement with the medium- and long-term effects on CNS monoamine metabolism described in the literature. As concerns statistical analysis, dichotomous or polytomous data obtained, e.g., by the Fox battery are not yet amenable to an adequate processing, due to the shortcomings of the available nonparametric tests. By contrast, mixed-model ANOVAs can cope with complex data obtained, e.g., in activity and learning tests. However, the available checks on various assumptions (normality, homogeneity of variance, sphericity) are not valid when nested factors, block factors and repeated measures coexist. Finally, the more usual cross-fostering procedures provide adequate information on some aspects (e.g., separation of main effects of prenatal treatments from postnatal maternal effects) but not on others.(ABSTRACT TRUNCATED AT 250 WORDS)

Cognitive Improving Effects by Highbush Blueberry (Vaccinium crymbosum L.) Vinegar on Scopolamine-Induced Amnesia Mice Model.

PubMed

Hong, Seong Min; Soe, Kyong Hee; Lee, Taek Hwan; Kim, In Sook; Lee, Young Min; Lim, Beong Ou

2018-01-10

The present study aimed to evaluate the preventive effects of highbush blueberry (Vaccinium corymbosum L.) vinegar (BV) on cognitive functions in a scopolamine (Sco)-induced amnesia model in mice. In this study, Sco (1 mg/kg, intraperitoneal injection) was used to induce amnesia. ICR mice were orally administered donepezil (5 mg/kg), blueberry extract (120 mg/kg), and BV (120 mg/kg) for 7 days. After inducing cognitive impairment by Sco, a behavioral assessment using behavior tests (i.e., Y-maze and passive avoidance tests) was performed. The BV group showed significantly restored cognitive function in the behavioral tests. BV facilitated cholinergic activity by inhibiting acetylcholinesterase activity, and enhanced antioxidant enzyme activity. Furthermore, BV was found to be rehabilitated in the cornu ammonis 1 neurons of hippocampus. In our study, we demonstrated that the memory protection conferred by BV was linked to activation of brain-derived neurotrophic factor (BDNF)/cAMP response element binding protein (CREB)/serine-threonine kinase (AKT) signaling.

Aircraft Wake Vortex Measurements at Denver International Airport

NASA Technical Reports Server (NTRS)

Dougherty, Robert P.; Wang, Frank Y.; Booth, Earl R.; Watts, Michael E.; Fenichel, Neil; D'Errico, Robert E.

2004-01-01

Airport capacity is constrained, in part, by spacing requirements associated with the wake vortex hazard. NASA's Wake Vortex Avoidance Project has a goal to establish the feasibility of reducing this spacing while maintaining safety. Passive acoustic phased array sensors, if shown to have operational potential, may aid in this effort by detecting and tracking the vortices. During August/September 2003, NASA and the USDOT sponsored a wake acoustics test at the Denver International Airport. The central instrument of the test was a large microphone phased array. This paper describes the test in general terms and gives an overview of the array hardware. It outlines one of the analysis techniques that is being applied to the data and gives sample results. The technique is able to clearly resolve the wake vortices of landing aircraft and measure their separation, height, and sinking rate. These observations permit an indirect estimate of the vortex circulation. The array also provides visualization of the vortex evolution, including the Crow instability.

No evidence for spectral jamming avoidance in echolocation behavior of foraging pipistrelle bats

PubMed Central

Götze, Simone; Koblitz, Jens C.; Denzinger, Annette; Schnitzler, Hans-Ulrich

2016-01-01

Frequency shifts in signals of bats flying near conspecifics have been interpreted as a spectral jamming avoidance response (JAR). However, several prerequisites supporting a JAR hypothesis have not been controlled for in previous studies. We recorded flight and echolocation behavior of foraging Pipistrellus pipistrellus while flying alone and with a conspecific and tested whether frequency changes were due to a spectral JAR with an increased frequency difference, or whether changes could be explained by other reactions. P. pipistrellus reacted to conspecifics with a reduction of sound duration and often also pulse interval, accompanied by an increase in terminal frequency. This reaction is typical of behavioral situations where targets of interest have captured the bat’s attention and initiated a more detailed exploration. All observed frequency changes were predicted by the attention reaction alone, and do not support the JAR hypothesis of increased frequency separation. Reaction distances of 1–11 m suggest that the attention response may be elicited either by detection of the conspecific by short range active echolocation or by long range passive acoustic detection of echolocation calls. PMID:27502900

Laser range measurement for a satellite navigation scheme and mid-range path selection and obstacle avoidance. M.S. Thesis

NASA Technical Reports Server (NTRS)

Zuraski, G. D.

1972-01-01

The functions of a laser rangefinder on board an autonomous Martian roving vehicle are discussed. The functions are: (1) navigation by means of a passive satellite and (2) mid-range path selection and obstacle avoidance. The feasibility of using a laser to make the necessary range measurements is explored and a preliminary design is presented. The two uses of the rangefinder dictate widely different operating parameters making it impossible to use the same system for both functions.

Intrauterine growth retardation (IUGR): epidemiology and etiology.

PubMed

Romo, Agustín; Carceller, Raquel; Tobajas, Javier

2009-02-01

Intrauterine growth retardation (IUGR) is mainly due to a pathologic slow-down in the fetal growth pace, resulting in a fetus that is unable to reach its growth potential. IUGR frequency will vary depending on the discrimination criteria adopted. It is extremely important to use local or national fetal growth graphs in order to avoid some confounding factors. IUGR incidence in newborns would be between 3% and 7% of the total population. In our experience it is 5.13% a figure similar to the one obtained by other authors but with a progressively higher incidence during the last decade. There are multiple maternal factors that can generally be grouped into constitutional and general factors given that they affect age, weight, race, maternal cardiac volume, etc, socioeconomic factors with key incidence in the mother's nutrition level, where a poor maternal nutrition level would be the key factor in this group. We have evaluated multiple factors as possible contributors to the IUGR risk: race, parents' age, mother's height (cm), mother's birth weight and before pregnancy (kg), ponderal gain and blood pressure during pregnancy, and previous SGA newborns. Socioeconomic factors like social class, parents' profession, habitual residence, salary, immigration, and diet were also evaluated. We also included variables such as total daily working time and time mothers spent standing up, daily sleeping time (hrs), stress self-perception test at work and primiparity age. Toxic factors during pregnancy: tobacco (active and passive), alcohol, drugs and coffee consumption. Fetal or utero-placental factors were considered. In our study, the most significant etiologic factors were: Active and passive tobacco consuming, mother's stress level, increase of total months worked during pregnancy, total daily working hours and time mothers spent standing up and finally, the parent's height. Our data support the main objective of reducing the incidence of SGA newborns after IUGR by fighting against tobacco from all fields, including the passive smoking habit, and improving the laboral conditions of the pregnant mother, lowering the number of daily hours worked, the physical activity and trying to avoid and to cope with stressful situations.

False-positive result when a diphenylcarbazide spot test is used on trivalent chromium-passivated zinc surfaces.

PubMed

Reveko, Valeriia; Lampert, Felix; Din, Rameez U; Thyssen, Jacob P; Møller, Per

2018-05-01

A colorimetric 1,5-diphenylcarbazide (DPC)-based spot test can be used to identify hexavalent chromium on various metallic and leather surfaces. DPC testing on trivalent chromium-passivated zinc surfaces has unexpectedly given positive results in some cases, apparently indicating the presence of hexavalent chromium; however, the presence of hexavalent chromium has never been confirmed with more sensitive and accurate test methods. To examine the presence of hexavalent chromium on trivalent chromium-passivated zinc surfaces with a DPC-based spot test. A colorimetric DPC spot test was used for the initial detection of hexavalent chromium on new and 1-year-aged trivalent chromium-passivated zinc surfaces. Then, X-ray photoelectron spectroscopy (XPS) was performed for all samples. The DPC spot test indicated the presence of hexavalent chromium in aged, but not new, trivalent chromium passivation on zinc; however, subsequent analysis by XPS could not confirm the presence of chromium in a hexavalent state. Unintended oxidation of DPC induced by atmospheric corrosion is suggested as a possible reason for the false-positive reaction of the DPC test on a trivalent chromium-passivated zinc surface. Further validation of the use of the DPC test for chromium-containing metallic surfaces is required. © 2018 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Environmental triggers and avoidance in the management of asthma

PubMed Central

Gautier, Clarisse; Charpin, Denis

2017-01-01

Identifying asthma triggers forms the basis of environmental secondary prevention. These triggers may be allergenic or nonallergenic. Allergenic triggers include indoor allergens, such as house dust mites (HDMs), molds, pets, cockroaches, and rodents, and outdoor allergens, such as pollens and molds. Clinical observations provide support for the role of HDM exposure as a trigger, although avoidance studies provide conflicting results. Molds and their metabolic products are now considered to be triggers of asthma attacks. Pets, dogs, and especially cats can undoubtedly trigger asthmatic symptoms in sensitized subjects. Avoidance is difficult and rarely adhered to by families. Cockroach allergens contribute to asthma morbidity, and avoidance strategies can lead to clinical benefit. Mouse allergens are mostly found in inner-city dwellings, but their implication in asthma morbidity is debated. In the outdoors, pollens can induce seasonal asthma in sensitized individuals. Avoidance relies on preventing pollens from getting into the house and on minimizing seasonal outdoor exposure. Outdoor molds may lead to severe asthma exacerbations. Nonallergenic triggers include viral infections, active and passive smoking, meteorological changes, occupational exposures, and other triggers that are less commonly involved. Viral infection is the main asthma trigger in children. Active smoking is associated with higher asthma morbidity, and smoking cessation interventions should be personalized. Passive smoking is also a risk factor for asthma exacerbation. The implementation of public smoking bans has led to a reduction in the hospitalization of asthmatic children. Air pollution levels have been linked with asthmatic symptoms, a decrease in lung function, and increased emergency room visits and hospitalizations. Since avoidance is not easy to achieve, clean air policies remain the most effective strategy. Indoor air is also affected by air pollutants, such as cigarette smoke and volatile organic compounds generated by building and cleaning materials. Occupational exposures include work-exacerbated asthma and work-related asthma. PMID:28331347

Zinc Chloride and Lead Acetate-Induced Passive Avoidance Memory Retention Deficits Reversed by Nicotine and Bucladesine in Mice.

PubMed

Tabrizian, Kaveh; Yazdani, Abdolmajid; Baheri, Behnam; Payandemehr, Borna; Sanati, Mehdi; Hashemzaei, Mahmoud; Miri, Abdolhossein; Zandkarimi, Majid; Belaran, Maryam; Fanoudi, Sahar; Sharifzadeh, Mohammad

2016-01-01

It is very important to investigate the neurotoxic effects of metals on learning and memory processes. In this study, we tried to investigate the effects and time course properties of oral administration of zinc chloride (25, 50, and 75 mg/kg, for 2 weeks), lead acetate (250, 750, 1,500, and 2,500 ppm for 4, 6 and 8 weeks), and their possible mechanisms on a model of memory function. For this matter, we examined the intra-peritoneal injections of nicotine (0.25, 0.5, 1, and 1.5 mg/kg) and bucladesine (50, 100, 300, and 600 nM/mouse) for 4 days alone and in combination with mentioned metals in the step-through passive avoidance task. Control animals received saline, drinking water, saline, and DMSO (dimethyl sulfoxide)/deionized water (1:9), respectively. At the end of each part of studies, animals were trained for 1 day in step-through task. The avoidance memory retention alterations were evaluated 24 and 48 h later in singular and combinational studies. Zinc chloride (75 mg/kg) oral gavage for 2 weeks decreased latency times compared to control animals. Also, lead acetate (750 ppm oral administrations for 8 weeks) caused significant lead blood levels and induced avoidance memory retention impairments. Four-days intra-peritoneal injection of nicotine (1 mg/kg) increased latency time compared to control animals. Finally, findings of this research showed that treatment with intra-peritoneal injections of nicotine (1 mg/kg) and/or bucladesine (600 nM/mouse) reversed zinc chloride- and lead acetate-induced avoidance memory retention impairments. Taken together, these results showed the probable role of cholinergic system and protein kinase A pathways in zinc chloride- and lead acetate-induced avoidance memory alterations.

Propagation of narrow-band-high-frequency clicks: measured and modeled transmission loss of porpoise-like clicks in porpoise habitats.

PubMed

DeRuiter, Stacy L; Hansen, Michael; Koopman, Heather N; Westgate, Andrew J; Tyack, Peter L; Madsen, Peter T

2010-01-01

Estimating the range at which harbor porpoises can detect prey items and environmental objects is integral to understanding their biosonar. Understanding the ranges at which they can use echolocation to detect and avoid obstacles is particularly important for strategies to reduce bycatch. Transmission loss (TL) during acoustic propagation is an important determinant of those detection ranges, and it also influences animal detection functions used in passive acoustic monitoring. However, common assumptions regarding TL have rarely been tested. Here, TL of synthetic porpoise clicks was measured in porpoise habitats in Canada and Denmark, and field data were compared with spherical spreading law and ray-trace (Bellhop) model predictions. Both models matched mean observations quite well in most cases, indicating that a spherical spreading law can usually provide an accurate first-order estimate of TL for porpoise sounds in porpoise habitat. However, TL varied significantly (+/-10 dB) between sites and over time in response to variability in seafloor characteristics, sound-speed profiles, and other short-timescale environmental fluctuations. Such variability should be taken into account in estimates of the ranges at which porpoises can communicate acoustically, detect echolocation targets, and be detected via passive acoustic monitoring.

C. S. Peirce's Dialogical Conception of Sign Processes

ERIC Educational Resources Information Center

Bergman, Mats

2005-01-01

This article examines the contention that the central concepts of C. S. Peirce's semeiotic are inherently communicational. It is argued that the Peircean approach avoids the pitfalls of objectivism and constructivism, rendering the sign-user neither a passive recipient nor an omnipotent creator of meaning. Consequently, semeiotic may serve as a…

The Draws and Drawbacks of College Students' Active Procrastination

ERIC Educational Resources Information Center

Hensley, Lauren C.

2016-01-01

When students procrastinate, they divert time from academics toward other activities, returning to academics at a later time. Active procrastination is a departure from the form of procrastination defined by scholars as passive (i.e., avoidant, maladaptive) in nature. Hensley selected the methodology (phenomenology) in order to undertake an…

Solar heated beehives

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hardin, B.

1985-02-01

A new translucent plastic cover for bee hives is described which will serve as a passive solar collector and insulator. Scientists at the USDA-ARS designed the cover to maintain bees in cold weather. It should be of interest to beekeepers in northern states who have had to destroy colonies to avoid overwintering costs.

[Nutrition in pregnancy - Practice recommendations of the Network "Healthy Start - Young Family Network"].

PubMed

Koletzko, B; Bauer, C-P; Bung, P; Cremer, M; Flothkötter, M; Hellmers, C; Kersting, M; Krawinkel, M; Przyrembel, H; Rasenack, R; Schäfer, T; Vetter, K; Wahn, U; Weißenborn, A; Wöckel, A

2012-06-01

Nutrition, physical activity and lifestyle in pregnancy influence maternal and child health. The "Healthy start - Young Family Network" supported by the German Government with the national action plan IN FORM developed recommendations on nutrition in pregnancy. Folic acid supplements (400 µg/day) should be started before pregnancy and continue for at least the first trimester. Iodine rich foods and salt and an iodine supplement (100-150 µg/day) are recommended. Long-chain omega-3 fatty acids should be provided with ≥ 1 weekly portion of oily sea fish, or a DHA-supplement if regular fish consumption is avoided. Vitamin D supplementation is advisable unless there is regular exposure to sunlight. Iron supplements should be used based on medical history and blood testing. Vegetarian diets with nutritional supplements can provide adequate nutrition, but counselling is recommended. In contrast, a vegan diet is inadequate and requires additional micronutrient supplementation. For risk reduction of listeriosis and toxoplasmosis, raw animal foods, soft cheeses and packed fresh salads should be avoided; fresh fruit, vegetables and salad should be washed well and consumed promptly. Pregnant women should remain physically active and perform sports with moderate intensity. They should avoid alcohol, active and passive smoking. Up to 3 daily cups of coffee are considered harmless, but energy drinks should be avoided. Childhood allergy is not reduced by avoiding certain foods in pregnancy whereas oily sea fish is recommended. Health care professions should lead parents to health-promoting lifestyles. Subjects of part 1 of the article are practice recommendations on nutrition, on energy needs, micronutrient needs and body weight/weight gain in pregnancy. © Georg Thieme Verlag KG Stuttgart · New York.

Foraging scent marks of bumblebees: footprint cues rather than pheromone signals

NASA Astrophysics Data System (ADS)

Wilms, Jessica; Eltz, Thomas

2008-02-01

In their natural habitat foraging bumblebees refuse to land on and probe flowers that have been recently visited (and depleted) by themselves, conspecifics or other bees, which increases their overall rate of nectar intake. This avoidance is often based on recognition of scent marks deposited by previous visitors. While the term ‘scent mark’ implies active labelling, it is an open question whether the repellent chemicals are pheromones actively and specifically released during flower visits, or mere footprints deposited unspecifically wherever bees walk. To distinguish between the two possibilities, we presented worker bumblebees ( Bombus terrestris) with three types of feeders in a laboratory experiment: unvisited control feeders, passive feeders with a corolla that the bee had walked over on its way from the nest (with unspecific footprints), and active feeders, which the bee had just visited and depleted, but which were immediately refilled with sugar water (potentially with specific scent marks). Bumblebees rejected both active and passive feeders more frequently than unvisited controls. The rate of rejection of passive feeders was only slightly lower than that of active feeders, and this difference vanished completely when passive corollas were walked over repeatedly on the way from the nest. Thus, mere footprints were sufficient to emulate the repellent effect of an actual feeder visit. In confirmation, glass slides on which bumblebees had walked on near the nest entrance accumulated hydrocarbons (alkanes and alkenes, C23 to C31), which had previously been shown to elicit repellency in flower choice experiments. We conclude that repellent scent marks are mere footprints, which foraging bees avoid when they encounter them in a foraging context.

Calcium homeostasis and protein kinase/phosphatase balance participate in nicotine-induced memory improvement in passive avoidance task in mice.

PubMed

Michalak, Agnieszka; Biala, Grazyna

2017-01-15

Long-term potentiation (LTP) and long-term depression (LTD) depend on specific postsynaptic Ca 2+ /calmodulin concentration. LTP results from Ca 2+ influx through the activated NMDA receptors or voltage-gated calcium channels (VGCCs) and is linked with activation of protein kinases including mitogen-activated protein kinase (MAPK). Weaker synaptic stimulation, as a result of low Ca 2+ influx, leads to activation of Ca 2+ /calmodulin-dependent phosphatase (calcineurin - CaN) and triggers LTD. Interestingly, both memory formation and drug addiction share similar neuroplastic changes. Nicotine, which is one of the most common addictive drugs, manifests its memory effects through nicotinic acetylcholine receptors (nAChRs). Because nAChRs may also gate Ca 2+ , it is suggested that calcium signaling pathways are involved in nicotine-induced memory effects. Within the scope of the study was to evaluate the importance of calcium homeostasis and protein kinase/phosphatase balance in nicotine-induced short- and long-term memory effects. To assess memory function in mice passive avoidance test was used. The presented results confirm that acute nicotine (0.1mg/kg) improves short- and long-term memory. Pretreatment with L-type VGCC blockers (amlodipine, nicardipine verapamil) increased nicotine-induced memory improvement in the context of short- and long-term memory. Pretreatment with FK-506 (a potent CaN inhibitor) enhanced short- but not long-term memory effects of nicotine, while SL-327 (a selective MAPK/ERK kinase inhibitor) attenuated both nicotine-induced short- and long-term memory improvement. Acute nicotine enhances both types of memory via L-type VGCC blockade and via ERK1/2 activation. Only short- but not long-term memory enhancement induced by nicotine is dependent on CaN inhibition. Copyright © 2016 Elsevier B.V. All rights reserved.

Effects of oxotremorine and physostigmine on the inhibitory avoidance impairment produced by amitriptyline in male and female mice.

PubMed

Monleón, Santiago; Urquiza, Adoración; Vinader-Caerols, Concepción; Parra, Andrés

2009-12-28

We have previously observed that amitriptyline and other antidepressants produce impairing effects on inhibitory avoidance (also called passive avoidance) in mice of both sexes. In the present study we investigated the involvement of the cholinergic system in the inhibitory avoidance impairment produced by acute amitriptyline in male and female CD1 mice. For this purpose, the effects on said task of acute i.p. administration of several doses of amitriptyline, either alone or in combination with the cholinergic agonists oxotremorine and physostigmine, were evaluated. Pre-training administration of 5, 7.5, 10 or 15 mg/kg of amitriptyline produced a significant impairment of inhibitory avoidance in both males and females. When oxotremorine (0.05 or 0.1 mg/kg) was co-administered with amitriptyline, the antidepressant's impairing effect was partially counteracted, although inhibitory avoidance learning was not significant. Physostigmine (0.15, 0.3 or 0.6 mg/kg) counteracted the impairment produced by amitriptyline, as mice treated with both drugs exhibited inhibitory avoidance learning. These results show that the inhibitory avoidance impairment produced by amitriptyline in male and female mice is mediated, at least partially, by the cholinergic system.

Dorsal hippocampal NMDA receptors mediate the interactive effects of arachidonylcyclopropylamide and MDMA/ecstasy on memory retrieval in rats.

PubMed

Ghaderi, Marzieh; Rezayof, Ameneh; Vousooghi, Nasim; Zarrindast, Mohammad-Reza

2016-04-03

A combination of cannabis and ecstasy may change the cognitive functions more than either drug alone. The present study was designed to investigate the possible involvement of dorsal hippocampal NMDA receptors in the interactive effects of arachidonylcyclopropylamide (ACPA) and ecstasy/MDMA on memory retrieval. Adult male Wistar rats were cannulated into the CA1 regions of the dorsal hippocampus (intra-CA1) and memory retrieval was examined using the step-through type of passive avoidance task. Intra-CA1 microinjection of a selective CB1 receptor agonist, ACPA (0.5-4ng/rat) immediately before the testing phase (pre-test), but not after the training phase (post-training), impaired memory retrieval. In addition, pre-test intra-CA1 microinjection of MDMA (0.5-1μg/rat) dose-dependently decreased step-through latency, indicating an amnesic effect of the drug by itself. Interestingly, pre-test microinjection of a higher dose of MDMA into the CA1 regions significantly improved ACPA-induced memory impairment. Moreover, pre-test intra-CA1 microinjection of a selective NMDA receptor antagonist, D-AP5 (1 and 2μg/rat) inhibited the reversal effect of MDMA on the impairment of memory retrieval induced by ACPA. Pre-test intra-CA1 microinjection of the same doses of D-AP5 had no effect on memory retrieval alone. These findings suggest that ACPA or MDMA consumption can induce memory retrieval impairment, while their co-administration improves this amnesic effect through interacting with hippocampal glutamatergic-NMDA receptor mechanism. Thus, it seems that the tendency to abuse cannabis with ecstasy may be for avoiding cognitive dysfunction. Copyright © 2015. Published by Elsevier Inc.

Commentary on "Capturing the Evasive Passive"

ERIC Educational Resources Information Center

Lillo-Martin, Diane; Snyder, William

2009-01-01

Passives has been the focus of much research in language acquisition since the 1970s. It has been clear from this research that young children seldom produce passives spontaneously, particularly "long" or "full" passives with a by-phrase; and they usually perform poorly on experimental tests of the comprehension of passives, especially passives of…

Functional Connectivity in Frequency-Tagged Cortical Networks During Active Harm Avoidance

PubMed Central

Miskovic, Vladimir; Príncipe, José C.; Keil, Andreas

2015-01-01

Abstract Many behavioral and cognitive processes are grounded in widespread and dynamic communication between brain regions. Thus, the quantification of functional connectivity with high temporal resolution is highly desirable for capturing in vivo brain function. However, many of the commonly used measures of functional connectivity capture only linear signal dependence and are based entirely on relatively simple quantitative measures such as mean and variance. In this study, the authors used a recently developed algorithm, the generalized measure of association (GMA), to quantify dynamic changes in cortical connectivity using steady-state visual evoked potentials (ssVEPs) measured in the context of a conditioned behavioral avoidance task. GMA uses a nonparametric estimator of statistical dependence based on ranks that are efficient and capable of providing temporal precision roughly corresponding to the timing of cognitive acts (∼100–200 msec). Participants viewed simple gratings predicting the presence/absence of an aversive loud noise, co-occurring with peripheral cues indicating whether the loud noise could be avoided by means of a key press (active) or not (passive). For active compared with passive trials, heightened connectivity between visual and central areas was observed in time segments preceding and surrounding the avoidance cue. Viewing of the threat stimuli also led to greater initial connectivity between occipital and central regions, followed by heightened local coupling among visual regions surrounding the motor response. Local neural coupling within extended visual regions was sustained throughout major parts of the viewing epoch. These findings are discussed in a framework of flexible synchronization between cortical networks as a function of experience and active sensorimotor coupling. PMID:25557925

Passive alcohol sensors tested in 3 states for youth alcohol enforcement

DOT National Transportation Integrated Search

1996-05-01

Passive alcohol sensors were tested in three states to determine their effectiveness in enforcing zero tolerance or low BAC laws for under 21 age drivers. The passive alcohol sensor was designed to sample the air immediately around the suspect for si...

Contribution of a Comparative Western Blot Method to Early Postnatal Diagnosis of Congenital Syphilis.

PubMed

Marangoni, Antonella; Foschi, Claudio; Capretti, Maria Grazia; Nardini, Paola; Compri, Monica; Corvaglia, Luigi Tommaso; Faldella, Giacomo; Cevenini, Roberto

2016-05-01

Serology has a pivotal role in the diagnosis of congenital syphilis (CS), but problems arise because of the passive transfer of IgG antibodies across the placenta. The aim of this study was to assess the diagnostic value of a comparative Western blot (WB) method finalized to match the IgG immunological profiles of mothers and their own babies at birth in order to differentiate between passively transmitted maternal antibodies and antibodies synthesized by the infants against Treponema pallidum Thirty infants born to mothers with unknown or inadequate treatment for syphilis were entered in a retrospective study, conducted at St. Orsola-Malpighi Hospital, Bologna, Italy. All of the infants underwent clinical, instrumental, and laboratory examinations, including IgM WB testing. For the retrospective study, an IgG WB assay was performed by blotting T. pallidum antigens onto nitrocellulose sheets and incubating the strips with serum specimens from mother-child pairs. CS was diagnosed in 11 out of the 30 enrolled infants; 9/11 cases received the definitive diagnosis within the first week of life, whereas the remaining two were diagnosed later because of increasing serological test titers. The use of the comparative IgG WB testing performed with serum samples from mother-child pairs allowed a correct CS diagnosis in 10/11 cases. The CS diagnosis was improved by a strategy combining comparative IgG WB results with IgM WB results, leading to a sensitivity of 100%. The comparative IgG WB test is thus a welcome addition to the conventional laboratory methods used for CS diagnosis, allowing identification and adequate treatment of infected infants and avoiding unnecessary therapy of uninfected newborns. Copyright © 2016, American Society for Microbiology. All Rights Reserved.

Prevalence, sociodemographic factors, psychological distress, and coping strategies related to compulsive buying: a cross sectional study in Galicia, Spain.

PubMed

Otero-López, José Manuel; Villardefrancos, Estíbaliz

2014-04-05

Compulsive buying has become a serious problem affecting a growing number of people in contemporary consumer societies. Nevertheless, research examining its prevalence in representative samples from the general population is still scarce and mainly focused on the exploration of sociodemographic factors, neglecting other aspects like psychological distress and coping styles. Therefore, this study intends to contribute to the cumulative knowledge by assessing compulsive buying prevalence in a representative sample from the general population in the region of Galicia, in Spain. Sociodemographic determinants, psychological symptoms, and coping strategies are also analyzed to clarify their role in this phenomenon. A random routes procedure was employed in the recruitment of the sample which was comprised of 2159 participants who were classified as either compulsive buyers or non-compulsive buyers. Both groups were compared regarding sociodemographic determinants, symptoms, and coping strategies through chi-square tests or analyses of variance. A multivariate logistic regression analysis was conducted to determine which of these determinants might play a part in the make up of a risk profile for compulsive buying. Estimated prevalence of compulsive buying was 7.1%. Compulsive buyers and non-compulsive buyers differed significantly in sex and age, with women and younger people showing a higher propensity for this phenomenon. Individuals with compulsive buying presented significantly higher scores on all the psychological symptoms considered. They also employed passive-avoidance coping strategies much more frequently and active strategies of problem solving and cognitive restructuring much less frequently. The logistic regression analysis results confirmed that being female, experiencing symptoms of anxiety, depression, and obsession-compulsion, and employing the passive-avoidance coping strategies of problem avoidance, wishful thinking, and self-criticism, all constituted risk factors for compulsive buying, whilst the increased age and the use of the active coping strategies of problem solving and cognitive restructuring were protection factors. Our findings revealed a substantial prevalence of compulsive buying. Additionally, the relevance of sociodemographic determinants, psychological distress, and coping strategies in this problem was confirmed. The establishment of a risk profile for compulsive buying based on these different sets of determinants would likely contribute to the development of more effective intervention programs.

MHC-disassortative mate choice and inbreeding avoidance in a solitary primate.

PubMed

Huchard, Elise; Baniel, Alice; Schliehe-Diecks, Susanne; Kappeler, Peter M

2013-08-01

Sexual selection theory suggests that choice for partners carrying dissimilar genes at the major histocompatibility complex (MHC) may play a role in maintaining genetic variation in animal populations by limiting inbreeding or improving the immunity of future offspring. However, it is often difficult to establish whether the observed MHC dissimilarity among mates drives mate choice or represents a by-product of inbreeding avoidance based on MHC-independent cues. Here, we used 454-sequencing and a 10-year study of wild grey mouse lemurs (Microcebus murinus), small, solitary primates from western Madagascar, to compare the relative importance on the mate choice of two MHC class II genes, DRB and DQB, that are equally variable but display contrasting patterns of selection at the molecular level, with DRB under stronger diversifying selection. We further assessed the effect of the genetic relatedness and of the spatial distance among candidate mates on the detection of MHC-dependent mate choice. Our results reveal inbreeding avoidance, along with disassortative mate choice at DRB, but not at DQB. DRB-disassortative mate choice remains detectable after excluding all related dyads (characterized by a relatedness coefficient r > 0), but varies slightly with the spatial distance among candidate mates. These findings suggest that the observed deviations from random mate choice at MHC are driven by functionally important MHC genes (like DRB) rather than passively resulting from inbreeding avoidance and further emphasize the need for taking into account the spatial and genetic structure of the population in correlative tests of MHC-dependent mate choice. © 2013 John Wiley & Sons Ltd.

Abnormal decision-making in generalized anxiety disorder: Aversion of risk or stimulus-reinforcement impairment?

PubMed

Teng, Cindy; Otero, Marcela; Geraci, Marilla; Blair, R J R; Pine, Daniel S; Grillon, Christian; Blair, Karina S

2016-03-30

There is preliminary data indicating that patients with generalized anxiety disorder (GAD) show impairment on decision-making tasks requiring the appropriate representation of reinforcement value. The current study aimed to extend this literature using the passive avoidance (PA) learning task, where the participant has to learn to respond to stimuli that engender reward and avoid responding to stimuli that engender punishment. Six stimuli engendering reward and six engendering punishment are presented once per block for 10 blocks of trials. Thirty-nine medication-free patients with GAD and 29 age-, IQ and gender matched healthy comparison individuals performed the task. In addition, indexes of social functioning as assessed by the Global Assessment of Functioning (GAF) scale were obtained to allow for correlational analyzes of potential relations between cognitive and social impairments. The results revealed a Group-by-Error Type-by-Block interaction; patients with GAD committed significantly more commission (passive avoidance) errors than comparison individuals in the later blocks (blocks 7,8, and 9). In addition, the extent of impairment on these blocks was associated with their functional impairment as measured by the GAF scale. These results link GAD with anomalous decision-making and indicate that a potential problem in reinforcement representation may contribute to the severity of expression of their disorder. Copyright © 2016. Published by Elsevier Ireland Ltd.

[An increase in allergic diseases in childhood--current hypotheses and possible prevention].

PubMed

Kurz, Herbert; Riedler, Jose

2003-01-01

During the last few decades there has ben a significant rise in the prevalence of allergic diseases such as asthma, hay fever and atopic dermatitis. Epidemiological studies strongly suggest that this increase is real and not due to changes in diagnostic labelling. It has become increasingly clear that a complex interplay between genetic and environmental factors account for this phenomenon. Genetically predisposed individuals are at an increased susceptibility to develop asthma or other allergic diseases when exposed to certain environmental or lifestyle factors. Particularly passive smoking has been shown to increase the risk for asthma in many studies and for atopy at least in some studies. This association is less clear for the exposure to sulfur dioxide, particulate matter, diesel exhaust and ozone. Lifestyle factors like socioeconomic status, sib-ship size, early childhood infections, dietary habits, growing up in antroposophic families or on a farm are more and more realised to be of great relevance for the development of allergic conditions. At the moment, there is a lot of uncertainty about which recommendations should be given for primary prevention. Recent studies have challenged the old paradigma that avoidance of early allergen contact could prevent the development of allergic disease. However, there is consensus that avoidance of smoking during pregnancy and avoidance of passive smoking during childhood should be recommended for primary prevention of asthma.

Antiamnesic effect of acyl-prolyl-containing dipeptide (GVS-111) in compression-induced damage to frontal cortex.

PubMed

Romanova, G A; Mirzoev, T K; Barskov, I V; Victorov, I V; Gudasheva, T A; Ostrovskaya, R U

2000-09-01

Antiamnestic effect of acyl-prolyl-containing dipeptide GVS-111 was demonstrated in rats with bilateral compression-induced damage to the frontal cortex. Both intraperitoneal and oral administration of the dipeptide improved retrieval of passive avoidance responses in rats with compression-induced cerebral ischemia compared to untreated controls.

Principal Leadership Styles and the Academic Achievement of Students with Disabilities: A Mixed Methods Approach

ERIC Educational Resources Information Center

Brander, Bryan Patrick

2013-01-01

The purpose of this study was to examine the relationship between principal leadership styles and the academic achievement of students with disabilities. Participants were North Carolina elementary and middle school principals and teachers. The researcher examined what leadership styles (transformational, transactional, or passive-avoidant) are…

An Evaluation of the Response Modulation Hypothesis in Relation to Attention-Deficit/ Hyperactivity Disorder

ERIC Educational Resources Information Center

Farmer, Richard F.; Rucklidge, Julia J.

2006-01-01

Several hypotheses related to Newman's (e.g., Patterson & Newman, 1993) response modulation hypothesis were examined among adolescents with attention-deficit/hyperactivity disorder (ADHD; n = 18) and normal controls (n = 23). Consistent with predictions, youth with ADHD committed more passive avoidance errors (PAEs) than controls during the latter…

The effect of facial expressions on peripersonal and interpersonal spaces.

PubMed

Ruggiero, Gennaro; Frassinetti, Francesca; Coello, Yann; Rapuano, Mariachiara; di Cola, Armando Schiano; Iachini, Tina

2017-11-01

Identifying individuals' intent through the emotional valence conveyed by their facial expression influences our capacity to approach-avoid these individuals during social interactions. Here, we explore if and how the emotional valence of others' facial expressiveness modulates peripersonal-action and interpersonal-social spaces. Through Immersive Virtual Reality, participants determined reachability-distance (for peripersonal space) and comfort-distance (for interpersonal space) from male/female virtual confederates exhibiting happy, angry and neutral facial expressions while being approached by (passive-approach) or walking toward (active-approach) them. Results showed an increase of distance when seeing angry rather than happy confederates in both approach conditions of comfort-distance. The effect also appeared in reachability-distance, but only in the passive-approach. Anger prompts avoidant behaviors, and thus an expansion of distance, particularly with a potential violation of near body space by an intruder. Overall, the findings suggest that peripersonal-action space, in comparison with interpersonal-social space, is similarly sensitive to the emotional valence of stimuli. We propose that this similarity could reflect a common adaptive mechanism shared by these spaces, presumably at different degrees, for ensuring self-protection functions.

ADN-1184 a monoaminergic ligand with 5-HT(6/7) receptor antagonist activity: pharmacological profile and potential therapeutic utility.

PubMed

Kołaczkowski, M; Mierzejewski, P; Bieńkowski, P; Wesołowska, A; Newman-Tancredi, A

2014-02-01

Many dementia patients exhibit behavioural and psychological symptoms (BPSD) that include psychosis, aggressivity, depression and anxiety. Antipsychotic drugs are frequently prescribed but fail to significantly attenuate mood deficits, may interfere with cognitive function and are associated with motor and cardiac side effects, which are problematic in elderly patients. A need therefore exists for drugs that are better suited for the treatment of BPSD. We used in vitro cellular and in vivo behavioural tests to characterize ADN-1184, a novel arylsulfonamide ligand with potential utility for treatment of BPSD. ADN-1184 exhibits substantial 5-HT6 /5-HT7 /5-HT2A /D2 receptor affinity and antagonist properties in vitro. In tests of antipsychotic-like activity, it reversed MK-801-induced hyperactivity and stereotypies and inhibited conditioned avoidance response (MED = 3 mg·kg(-1) i.p.). Remarkably, ADN-1184 also reduced immobility time in the forced swim test at low doses (0.3 and 1 mg·kg(-1) i.p.; higher doses were not significantly active). Notably, up to 30 mg·kg(-1) ADN-1184 did not impair memory performance in the passive avoidance test or elicit significant catalepsy and only modestly inhibited spontaneous locomotor activity (MED = 30 mg·kg(-1) i.p.). ADN-1184 combines antipsychotic-like with antidepressant-like properties without interfering with memory function or locomotion. This profile is better than that of commonly used atypical antipsychotics tested under the same conditions and suggests that it is feasible to identify drugs that improve BPSD, without exacerbating cognitive deficit or movement impairment, which are of particular concern in patients with dementia. © 2013 The British Pharmacological Society.

ORION Project-(SPLASH) Structural Passive Landing Attenuation fo

NASA Image and Video Library

2011-07-12

ORION Project-(SPLASH) Structural Passive Landing Attenuation for Survivability of Human Crew (BTA) Boiler Plate Test Article Water Impact Test-Pot Phase"0" Test Tested at the Hydro Impact Basin at the Landing and Impact Research Facility (Gantry)

Passive in-vehicle driver breath alcohol detection using advanced sensor signal acquisition and fusion.

PubMed

Ljungblad, Jonas; Hök, Bertil; Allalou, Amin; Pettersson, Håkan

2017-05-29

The research objective of the present investigation is to demonstrate the present status of passive in-vehicle driver breath alcohol detection and highlight the necessary conditions for large-scale implementation of such a system. Completely passive detection has remained a challenge mainly because of the requirements on signal resolution combined with the constraints of vehicle integration. The work is part of the Driver Alcohol Detection System for Safety (DADSS) program aiming at massive deployment of alcohol sensing systems that could potentially save thousands of American lives annually. The work reported here builds on earlier investigations, in which it has been shown that detection of alcohol vapor in the proximity of a human subject may be traced to that subject by means of simultaneous recording of carbon dioxide (CO 2 ) at the same location. Sensors based on infrared spectroscopy were developed to detect and quantify low concentrations of alcohol and CO 2 . In the present investigation, alcohol and CO 2 were recorded at various locations in a vehicle cabin while human subjects were performing normal in-step procedures and driving preparations. A video camera directed to the driver position was recording images of the driver's upper body parts, including the face, and the images were analyzed with respect to features of significance to the breathing behavior and breath detection, such as mouth opening and head direction. Improvement of the sensor system with respect to signal resolution including algorithm and software development, and fusion of the sensor and camera signals was successfully implemented and tested before starting the human study. In addition, experimental tests and simulations were performed with the purpose of connecting human subject data with repeatable experimental conditions. The results include occurrence statistics of detected breaths by signal peaks of CO 2 and alcohol. From the statistical data, the accuracy of breath alcohol estimation and timing related to initial driver routines (door opening, taking a seat, door closure, buckling up, etc.) can be estimated. The investigation confirmed the feasibility of passive driver breath alcohol detection using our present system. Trade-offs between timing and sensor signal resolution requirements will become critical. Further improvement of sensor resolution and system ruggedness is required before the results can be industrialized. It is concluded that a further important step toward completely passive detection of driver breath alcohol has been taken. If required, the sniffer function with alcohol detection capability can be combined with a subsequent highly accurate breath test to confirm the driver's legal status using the same sensor device. The study is relevant to crash avoidance, in particular driver monitoring systems and driver-vehicle interface design.

Examining the Construct Validity of the MMPI-2-RF Interpersonal Functioning Scales Using the Computerized Adaptive Test of Personality Disorder as a Comparative Framework.

PubMed

Franz, Annabel O; Harrop, Tiffany M; McCord, David M

2017-01-01

This study aimed to examine the construct validity of the Minnesota Multiphasic Personality Inventory-2 Restructured Form (MMPI-2-RF) interpersonal functioning scales (Ben-Porath & Tellegen, 2008/2011 ) using as a criterion measure the Computerized Adaptive Test of Personality Disorder-Static Form (CAT-PD-SF; Simms et al., 2011 ). Participants were college students (n = 98) recruited through the university subject pool. A series of a priori hypotheses were developed for each of the 6 interpersonal functioning scales of the MMPI-2-RF, expressed as predicted correlations with construct-relevant CAT-PD-SF scales. Of the 27 specific predictions, 21 were supported by substantial (≥ |.30|) correlations. The MMPI-2-RF Family Problems scale (FML) demonstrated the strongest correlations with CAT-PD-SF scales Anhedonia and Mistrust; Cynicism (RC3) was most highly correlated with Mistrust and Norm Violation; Interpersonal Passivity (IPP) was most highly correlated with Domineering and Rudeness; Social Avoidance (SAV) was most highly correlated with Social Withdrawal and Anhedonia; Shyness (SHY) was most highly correlated with Social Withdrawal and Anxioiusness; and Disaffiliativeness (DSF) was most highly correlated with Emotional Detachment and Mistrust. Results are largely consistent with hypotheses suggesting support for both models of constructs relevant to interpersonal functioning. Future research designed to more precisely differentiate Social Avoidance (SAV) and Shyness (SHY) is suggested.

Bisphenol-A rapidly enhanced passive avoidance memory and phosphorylation of NMDA receptor subunits in hippocampus of young rats

DOE Office of Scientific and Technical Information (OSTI.GOV)

Xu Xiaohong, E-mail: xuxh63@zjnu.cn; Li Tao; Luo Qingqing

Bisphenol-A (BPA), an endocrine disruptor, is found to influence development of brain and behaviors in rodents. The previous study indicated that perinatal exposure to BPA impaired learning-memory and inhibited N-methyl-D-aspartate receptor (NMDAR) subunits expressions in hippocampus during the postnatal development in rats; and in cultured hippocampal neurons, BPA rapidly promotes dynamic changes in dendritic morphology through estrogen receptor-mediated pathway by concomitant phosphorylation of NMDAR subunit NR2B. In the present study, we examined the rapid effect of BPA on passive avoidance memory and NMDAR in the developing hippocampus of Sprague-Dawley rats at the age of postnatal day 18. The results showedmore » that BPA or estradiol benzoate (EB) rapidly extended the latency to step down from the platform 1 h after footshock and increased the phosphorylation levels of NR1, NR2B, and mitogen-activated extracellular signal-regulated kinase (ERK) in hippocampus within 1 h. While 24 h after BPA or EB treatment, the improved memory and the increased phosphorylation levels of NR1, NR2B, ERK disappeared. Furthermore, pre-treatment with an estrogen receptors (ERs) antagonist, ICI182,780, or an ERK-activating kinase inhibitor, U0126, significantly attenuated EB- or BPA-induced phosphorylations of NR1, NR2B, and ERK within 1 h. These data suggest that BPA rapidly enhanced short-term passive avoidance memory in the developing rats. A non-genomic effect via ERs may mediate the modulation of the phosphorylation of NMDAR subunits NR1 and NR2B through ERK signaling pathway. - Highlights: > BPA rapidly extended the latency to step down from platform 1 h after footshock. > BPA rapidly increased pNR1, pNR2B, and pERK in hippocampus within 1 h. > ERs antagonist or MEK inhibitor attenuated BPA-induced pNR1, pNR2B, and pERK.« less

ORION Project-(SPLASH) Structural Passive Landing Attenuation fo

NASA Image and Video Library

2011-07-21

ORION Project-(SPLASH) Structural Passive Landing Attenuation for Survivability of Human Crew (BTA) Boiler Plate Test Article Water Impact Test-Pot Phase"0" Test POT#2 Tested at the Hydro Impact Basin at the Landing and Impact Research Facility (Gantry)

ORION Project-(SPLASH) Structural Passive Landing Attenuation fo

NASA Image and Video Library

2011-12-13

ORION Project-(SPLASH) Structural Passive Landing Attenuation for Survivability of Human Crew (BTA) Boiler Plate Test Article Water Impact Test-Pit Phase 4 Test or Pit 4 Tested at the Hydro Impact Basin at the Landing and Impact Research Facility (Gantry)

Obstacle-avoiding robot with IR and PIR motion sensors

NASA Astrophysics Data System (ADS)

Ismail, R.; Omar, Z.; Suaibun, S.

2016-10-01

Obstacle avoiding robot was designed, constructed and programmed which may be potentially used for educational and research purposes. The developed robot will move in a particular direction once the infrared (IR) and the PIR passive infrared (PIR) sensors sense a signal while avoiding the obstacles in its path. The robot can also perform desired tasks in unstructured environments without continuous human guidance. The hardware was integrated in one application board as embedded system design. The software was developed using C++ and compiled by Arduino IDE 1.6.5. The main objective of this project is to provide simple guidelines to the polytechnic students and beginners who are interested in this type of research. It is hoped that this robot could benefit students who wish to carry out research on IR and PIR sensors.

Photo-stability and time-resolved photoluminescence study of colloidal CdSe/ZnS quantum dots passivated in Al{sub 2}O{sub 3} using atomic layer deposition

DOE Office of Scientific and Technical Information (OSTI.GOV)

Cheng, Chih-Yi; Mao, Ming-Hua, E-mail: mhmao@ntu.edu.tw; Graduate Institute of Electronics Engineering, National Taiwan University, Taipei 10617, Taiwan

2016-08-28

We report photo-stability enhancement of colloidal CdSe/ZnS quantum dots (QDs) passivated in Al{sub 2}O{sub 3} thin film using the atomic layer deposition (ALD) technique. 62% of the original peak photoluminescence (PL) intensity remained after ALD. The photo-oxidation and photo-induced fluorescence enhancement effects of both the unpassivated and passivated QDs were studied under various conditions, including different excitation sources, power densities, and environment. The unpassivated QDs showed rapid PL degradation under high excitation due to strong photo-oxidation in air while the PL intensity of Al{sub 2}O{sub 3} passivated QDs was found to remain stable. Furthermore, recombination dynamics of the unpassivated andmore » passivated QDs were investigated by time-resolved measurements. The average lifetime of the unpassivated QDs decreases with laser irradiation time due to photo-oxidation. Photo-oxidation creates surface defects which reduces the QD emission intensity and enhances the non-radiative recombination rate. From the comparison of PL decay profiles of the unpassivated and passivated QDs, photo-oxidation-induced surface defects unexpectedly also reduce the radiative recombination rate. The ALD passivation of Al{sub 2}O{sub 3} protects QDs from photo-oxidation and therefore avoids the reduction of radiative recombination rate. Our experimental results demonstrated that passivation of colloidal QDs by ALD is a promising method to well encapsulate QDs to prevent gas permeation and to enhance photo-stability, including the PL intensity and carrier lifetime in air. This is essential for the applications of colloidal QDs in light-emitting devices.« less

Analysis of the 5-HT1A receptor involvement in passive avoidance in the rat

PubMed Central

Misane, Ilga; Johansson, Christina; Ove Ögren, Sven

1998-01-01

The effects of the 5-HT2A/2C agonist DOB, the selective 5-HT1A agonist NDO 008 (3-dipropylamino-5-hydroxychroman), and the two enantiomers of the selective 5-HT1A agonist 8-OH-DPAT (R(+)-8-OH-DPAT and S(−)-8-OH-DPAT) were studied in a step-through passive avoidance (PA) test in the male rat.The 5-HT1A agonists injected prior to training (conditioning) produced a dose-dependent impairment of PA retention when examined 24 h later. R(+)-8-OH-DPAT was four times more effective than S(−)-8-OH-DPAT to cause an impairment of PA retention. Both NDO 008 and the two enantiomers of 8-OH-DPAT induced the serotonin syndrome at the dose range that produced inhibition of the PA response, thus, indicating activation of postsynaptic 5-HT1A receptors.Neither NDO 008 nor R(+)-8-OH-DPAT induced head-twitches, a behavioural response attributed to stimulation of postsynaptic 5-HT2A receptors. In contrast, DOB induced head-twitches at the 0.01 mg kg−1 dose while a 200 times higher dose was required to produce a significant impairment of PA retention.The impairment of PA retention induced by both NDO 008 and R(+)-8-OH-DPAT was fully blocked by the active S(+)- enantiomer of the selective 5-HT1A antagonist WAY 100135 and the mixed 5-HT1A/β-adrenoceptor antagonist L(−)-alprenolol. In contrast, the mixed 5-HT2A/2C antagonists ketanserin and pirenperone were found to be ineffective. Moreover, the β2-adrenoceptor antagonist ICI 118551, the β1-antagonist metoprolol as well as the mixed β-adrenoceptor blocker D(+)-alprenolol all failed to modify the deficit of PA retention by NDO 008 and R(+)-8-OH-DPAT. None of the 5-HT1A or 5-HT2A/2C receptor antagonists tested or the β-blockers altered PA retention by themselves.A 3 day pretreatment procedure (200+100+100 mg kg−1) with the tryptophan hydroxylase inhibitor p-chlorophenylalanine (PCPA) did not alter PA retention and did not prevent the inhibitory action of the 5-HT1A agonists, indicating that their effects on PA do not depend on endogenous 5-HT.The effects of NDO 008 on PA were also studied using a state-dependent learning paradigm. NDO 008 was found to produce a disruption of PA when given either prior to training or retention or both prior to training and retention but it failed to affect PA retention when given immediately after training.These findings indicate that the deficit of passive avoidance retention induced by the 5-HT1A agonists is mainly a result of stimulation of postsynaptic 5-HT1A receptors but not 5-HT2A receptors. The 5-HT1A receptor stimulation appears to interfere with learning processes operating at both acquisition and retrieval. PMID:9806333

Influence of impact speed on head and brain injury outcome in vulnerable road user impacts to the car hood.

PubMed

Fredriksson, Rikard; Zhang, Liying; Boström, Ola; Yang, King

2007-10-01

EuroNCAP and regulations in Europe and Japan evaluate the pedestrian protection performance of cars. The test methods are similar and they all have requirements for the passive protection of the hood area at a pedestrian to car impact speed of 40 km/h. In Europe, a proposal for a second phase of the regulation mandates a brake-assist system along with passive requirements. The system assists the driver in optimizing the braking performance during panic braking, resulting in activation only when the driver brakes sufficiently. In a European study this was estimated to occur in about 50% of pedestrian accidents. A future system for brake assistance will likely include automatic braking, in response to a pre-crash sensor, to avoid or mitigate injuries of vulnerable road users. An important question is whether these systems will provide sufficient protection, or if a parallel, passive pedestrian protection system will be necessary. This study investigated the influence of impact speed on head and brain injury risk, in impacts to the carhood. One car model was chosen and a rigid adjustable plate was mounted under the hood. Free-flying headform impacts were carried out at 20 and 30 km/h head impact velocities at different under-hood distances, 20 to 100 mm; and were compared to earlier tests at 40 km/h. The EEVC WG17 adult pedestrian headform was used for non-rotating tests and a Hybrid III adult 50th percentile head was used for rotational tests where linear and rotational acceleration was measured. Data from the rotational tests was used as input to a validated finite element model of the human head, the Wayne State University Head Injury Model (WSUHIM). The model was utilized to assess brain injury risk and potential injury mechanism in a pedestrian-hood impact. Although this study showed that it was not necessarily true that a lower HIC value reduced the risk for brain injury, it appeared, for the tested car model, under-hood distances of 60 mm in 20 km/h and 80 mm in 30 km/h reduced head injury values for both skull fractures and brain injuries. An earlier study showed that the corresponding value for a test speed of 40 km/h is 100 mm. A 10 km/h reduction in head impact velocity, as in automatic braking, allowed 20 mm less under-hood clearance with maintained head protection of the vulnerable road user.

The cognitive architecture of anxiety-like behavioral inhibition.

PubMed

Bach, Dominik R

2017-01-01

The combination of reward and potential threat is termed approach/avoidance conflict and elicits specific behaviors, including passive avoidance and behavioral inhibition (BI). Anxiety-relieving drugs reduce these behaviors, and a rich psychological literature has addressed how personality traits dominated by BI predispose for anxiety disorders. Yet, a formal understanding of the cognitive inference and planning processes underlying anxiety-like BI is lacking. Here, we present and empirically test such formalization in the terminology of reinforcement learning. We capitalize on a human computer game in which participants collect sequentially appearing monetary tokens while under threat of virtual "predation." First, we demonstrate that humans modulate BI according to experienced consequences. This suggests an instrumental implementation of BI generation rather than a Pavlovian mechanism that is agnostic about action outcomes. Second, an internal model that would make BI adaptive is expressed in an independent task that involves no threat. The existence of such internal model is a necessary condition to conclude that BI is under model-based control. These findings relate a plethora of human and nonhuman observations on BI to reinforcement learning theory, and crucially constrain the quest for its neural implementation. (PsycINFO Database Record (c) 2016 APA, all rights reserved).

Sound localization in common vampire bats: Acuity and use of the binaural time cue by a small mammal

PubMed Central

Heffner, Rickye S.; Koay, Gimseong; Heffner, Henry E.

2015-01-01

Passive sound-localization acuity and the ability to use binaural time and intensity cues were determined for the common vampire bat (Desmodus rotundus). The bats were tested using a conditioned suppression/avoidance procedure in which they drank defibrinated blood from a spout in the presence of sounds from their right, but stopped drinking (i.e., broke contact with the spout) whenever a sound came from their left, thereby avoiding a mild shock. The mean minimum audible angle for three bats for a 100-ms noise burst was 13.1°—within the range of thresholds for other bats and near the mean for mammals. Common vampire bats readily localized pure tones of 20 kHz and higher, indicating they could use interaural intensity-differences. They could also localize pure tones of 5 kHz and lower, thereby demonstrating the use of interaural time-differences, despite their very small maximum interaural distance of 60 μs. A comparison of the use of locus cues among mammals suggests several implications for the evolution of sound localization and its underlying anatomical and physiological mechanisms. PMID:25618037

Prolongation of SMAP to Spatiotemporally Seamless Coverage of Continental U.S. Using a Deep Learning Neural Network

NASA Astrophysics Data System (ADS)

Fang, Kuai; Shen, Chaopeng; Kifer, Daniel; Yang, Xiao

2017-11-01

The Soil Moisture Active Passive (SMAP) mission has delivered valuable sensing of surface soil moisture since 2015. However, it has a short time span and irregular revisit schedules. Utilizing a state-of-the-art time series deep learning neural network, Long Short-Term Memory (LSTM), we created a system that predicts SMAP level-3 moisture product with atmospheric forcings, model-simulated moisture, and static physiographic attributes as inputs. The system removes most of the bias with model simulations and improves predicted moisture climatology, achieving small test root-mean-square errors (<0.035) and high-correlation coefficients >0.87 for over 75% of Continental United States, including the forested southeast. As the first application of LSTM in hydrology, we show the proposed network avoids overfitting and is robust for both temporal and spatial extrapolation tests. LSTM generalizes well across regions with distinct climates and environmental settings. With high fidelity to SMAP, LSTM shows great potential for hindcasting, data assimilation, and weather forecasting.

A ridge tracking algorithm and error estimate for efficient computation of Lagrangian coherent structures.

PubMed

Lipinski, Doug; Mohseni, Kamran

2010-03-01

A ridge tracking algorithm for the computation and extraction of Lagrangian coherent structures (LCS) is developed. This algorithm takes advantage of the spatial coherence of LCS by tracking the ridges which form LCS to avoid unnecessary computations away from the ridges. We also make use of the temporal coherence of LCS by approximating the time dependent motion of the LCS with passive tracer particles. To justify this approximation, we provide an estimate of the difference between the motion of the LCS and that of tracer particles which begin on the LCS. In addition to the speedup in computational time, the ridge tracking algorithm uses less memory and results in smaller output files than the standard LCS algorithm. Finally, we apply our ridge tracking algorithm to two test cases, an analytically defined double gyre as well as the more complicated example of the numerical simulation of a swimming jellyfish. In our test cases, we find up to a 35 times speedup when compared with the standard LCS algorithm.

Synthesis and nootropic activity of some 2,3-dihydro-1H-isoindol-1-one derivatives structurally related with piracetam.

PubMed

Reyes, Adelfo; Huerta, Leticia; Alfaro, Marisol; Navarrete, Andrés

2010-11-01

Three 2,3-dihydro-1H-isoindol-1-ones structurally related with piracetam (=2-oxopyrrolidine-1-acetamide) have been synthesized and tested for their nootropic effects in the passive avoidance test in mice. Compounds (RS)-2, (R,R)-3, and (R,S)-3 were obtained in good yields in only two steps starting from methyl DL-phthaloylalanine. Compound (RS)-2 exhibited nootropic activity at lower doses than piracetam, used as reference drug, but it showed lower efficacy. Whereas diastereoisomers (R,R)-3 and (R,S)-3 were as potent as piracetam to revert amnesia induced by scopolamine, (R,S)-3 showed lower efficacy than (R,R)-3. Only (R,R)-3 showed myorelaxant effect at doses of 10 and 30 mg/kg; other compounds did not exhibit any anticonvulsant, sedative, myorelaxant, or impaired motor-coordination effect in mice. These synthesized 2,3-dihydro-1H-isoindol-1-one derivatives constitute a new kind of nootropic compounds.

Exposure to Novelty Weakens Conditioned Fear in Long-Evans Rats

ERIC Educational Resources Information Center

Anderson, Matthew J.; Burpee, Tara E.; Wall, Matthew J.; McGraw, Justin J.

2013-01-01

The present study sought to determine whether post-training exposure to a novel or familiar object, encountered in either the location of the original fear conditioning (black compartment of a passive avoidance {PA} chamber) or in a neutral setting (open field where initial object training had occurred) would prove capable of reducing fear at…

Teachers' Perception of Their Principal's Leadership Style and the Effects on Student Achievement in Improving and Non-Improving Schools

ERIC Educational Resources Information Center

Hardman, Brenda Kay

2011-01-01

Teachers' perceptions of their school leaders influence student achievement in their schools. The extent of this influence is examined in this study. This quantitative study examined teachers' perceptions of the leadership style of their principals as transformational, transactional or passive-avoidant in improving and non-improving schools in…

The Inevitability of Conflict and the Importance of Its Resolution in Christian Higher Education

ERIC Educational Resources Information Center

Ennis, Leslie Sturdivant

2008-01-01

Among Christian adherents, the subject of conflict and its proper resolution has been a source of misunderstanding and angst for centuries. New Testament admonitions concerning the proper Christian life have traditionally focused on passivism and have been interpreted broadly by Christendom to require avoidance of all conflict as a virtue. The…

Lindera melissifolia responses to flood durations and light regimes suggest strategies for recovery and conservation

Treesearch

Brian Roy Lockhart; Emile S. Gardiner; Theodor D. Leininger; Paul B. Hamel; Kristina F. Connor; Margaret S. Devall; Nathan M. Schiff; A. Dan Wilson

2013-01-01

Passive management to preserve endangered plant species involves measures to avoid anthropogenic disturbance of natural populations, but this approach may not sustain plants that require disturbance-maintained habitats. Active management is often necessary to maintain existing habitats or provide new habitats for endangered species recovery. Our objective was to...

Reversal of Trimethyltin-Induced Learning and Memory Deficits by 3,5-Dicaffeoylquinic Acid.

PubMed

Kang, Jin Yong; Park, Seon Kyeong; Guo, Tian Jiao; Ha, Jeong Su; Lee, Du Sang; Kim, Jong Min; Lee, Uk; Kim, Dae Ok; Heo, Ho Jin

2016-01-01

The antiamnesic effect of 3,5-dicaffeoylquinic acid (3,5-diCQA) as the main phenolic compound in Artemisia argyi H. extract on cognitive dysfunction induced by trimethyltin (TMT) (7.1  μ g/kg of body weight; intraperitoneal injection) was investigated in order to assess its ameliorating function in mice. In several behavioral tests, namely, the Y-maze, passive avoidance, and Morris water maze (MWM) test, 3,5-diCQA significantly ameliorated learning and memory deficits. After the behavioral tests, brain tissues from the mice were analyzed to characterize the basis of the neuroprotective effect. Acetylcholine (ACh) levels increased, whereas the activity of acetylcholinesterase (AChE) decreased upon administration of 3,5-diCQA. In addition, 3,5-diCQA effectively protected against an increase in malondialdehyde (MDA) content, an increase in the oxidized glutathione (GSH) ratio, and a decline of total superoxide dismutase (SOD) level. 3,5-diCQA may prevent neuronal apoptosis through the protection of mitochondrial activities and the repression of apoptotic signaling molecules such as p-Akt, BAX, and p-tau (Ser 404).

Reversal of Trimethyltin-Induced Learning and Memory Deficits by 3,5-Dicaffeoylquinic Acid

PubMed Central

Kang, Jin Yong; Park, Seon Kyeong; Guo, Tian Jiao; Ha, Jeong Su; Lee, Du Sang; Kim, Jong Min; Lee, Uk; Kim, Dae Ok

2016-01-01

The antiamnesic effect of 3,5-dicaffeoylquinic acid (3,5-diCQA) as the main phenolic compound in Artemisia argyi H. extract on cognitive dysfunction induced by trimethyltin (TMT) (7.1 μg/kg of body weight; intraperitoneal injection) was investigated in order to assess its ameliorating function in mice. In several behavioral tests, namely, the Y-maze, passive avoidance, and Morris water maze (MWM) test, 3,5-diCQA significantly ameliorated learning and memory deficits. After the behavioral tests, brain tissues from the mice were analyzed to characterize the basis of the neuroprotective effect. Acetylcholine (ACh) levels increased, whereas the activity of acetylcholinesterase (AChE) decreased upon administration of 3,5-diCQA. In addition, 3,5-diCQA effectively protected against an increase in malondialdehyde (MDA) content, an increase in the oxidized glutathione (GSH) ratio, and a decline of total superoxide dismutase (SOD) level. 3,5-diCQA may prevent neuronal apoptosis through the protection of mitochondrial activities and the repression of apoptotic signaling molecules such as p-Akt, BAX, and p-tau (Ser 404). PMID:28105250

Antiamnesic Effect of Broccoli (Brassica oleracea var. italica) Leaves on Amyloid Beta (Aβ)1-42-Induced Learning and Memory Impairment.

PubMed

Park, Seon Kyeong; Ha, Jeong Su; Kim, Jong Min; Kang, Jin Yong; Lee, Du Sang; Guo, Tian Jiao; Lee, Uk; Kim, Dae-Ok; Heo, Ho Jin

2016-05-04

To examine the antiamnesic effects of broccoli (Brassica oleracea var. italica) leaves, we performed in vitro and in vivo tests on amyloid beta (Aβ)-induced neurotoxicity. The chloroform fraction from broccoli leaves (CBL) showed a remarkable neuronal cell-protective effect and an inhibition against acetylcholinesterase (AChE). The ameliorating effect of CBL on Aβ1-42-induced learning and memory impairment was evaluated by Y-maze, passive avoidance, and Morris water maze tests. The results indicated improving cognitive function in the CBL group. After the behavioral tests, antioxidant effects were detected by superoxide dismutase (SOD), oxidized glutathione (GSH)/total GSH, and malondialdehyde (MDA) assays, and inhibition against AChE was also presented in the brain. Finally, oxo-dihydroxy-octadecenoic acid (oxo-DHODE) and trihydroxy-octadecenoic acid (THODE) as main compounds were identified by quadrupole time-of-flight ultraperformance liquid chromatography (Q-TOF UPLC-MS) analysis. Therefore, our studies suggest that CBL could be used as a natural resource for ameliorating Aβ1-42-induced learning and memory impairment.

Effects of active vs. passive recovery on repeated rugby-specific exercises.

PubMed

Jougla, A; Micallef, J P; Mottet, D

2010-05-01

The aim of this study was to determine the effects of active vs. passive recovery on performance of a rugby-specific intermittent test in rugby union players. Seven male rugby players (20.6+/-0.5 yrs; 181.9+/-10.0 cm; 94.5+/-12.8 kg) performed in random order, over two separate sessions, a specific repeated-sprint rugby test, the Narbonne test (6 x 4 consecutive actions: 1, scrummaging; 2, agility sprinting; 3, tackling; 4, straight sprinting) with 30s of passive or active recovery (running at 50% of maximal aerobic speed). The Narbonne tests were completed before (pre-test) and after (post-test) a 30-min rugby match. During the Narbonne test, scrum forces, agility and sprint times, heart rate and rate of perceived exertion were measured. Scrum forces were lower in active (74.9+/-13.4 kg) than in passive recovery (90.4+/-20.9 kg), only during the post-test (p<0.05). Fatigue index (%) (p<0.05) and total sprint time (s) (p<0.01) were significantly greater in active than in passive recovery, both during the pre-test (11.5+/-5.7% vs. 6.7+/-4.5% and 18.1+/-1.3s vs. 16.9+/-0.9s) and the post-test (7.3+/-3.3% vs. 4.3+/-1.5% and 18.3+/-1.6s vs. 16.9+/-1.1s). Consequently, the results indicated that passive recovery enabled better performance during the Narbonne test. However, it is obviously impractical to suggest that players should stand still during and following repeated-sprint bouts: the players have to move to ensure they have taken an optimal position. 2009 Sports Medicine Australia. Published by Elsevier Ltd. All rights reserved.

Folding Elastic Thermal Surface - FETS

NASA Technical Reports Server (NTRS)

Urquiza, Eugenio; Zhang, Burt X.; Thelen, Michael P.; Rodriquez, Jose I.; Pellegrino, Sergio

2013-01-01

The FETS is a light and compact thermal surface (sun shade, IR thermal shield, cover, and/or deployable radiator) that is mounted on a set of offset tape-spring hinges. The thermal surface is constrained during launch and activated in space by a thermomechanical latch such as a wax actuator. An application-specific embodiment of this technology developed for the MATMOS (Mars Atmospheric Trace Molecule Occultation Spectrometer) project serves as a deployable cover and thermal shield for its passive cooler. The FETS fits compactly against the instrument within the constrained launch envelope, and then unfolds into a larger area once in space. In this application, the FETS protects the passive cooler from thermal damage and contamination during ground operations, launch, and during orbit insertion. Once unfolded or deployed, the FETS serves as a heat shield, intercepting parasitic heat loads by blocking the passive cooler s view of the warm spacecraft. The technology significantly enhances the capabilities of instruments requiring either active or passive cooling of optical detectors. This can be particularly important for instruments where performance is limited by the available radiator area. Examples would be IR optical instruments on CubeSATs or those launched as hosted payloads because radiator area is limited and views are often undesirable. As a deployable radiator, the panels making up the FETS are linked thermally by thermal straps and heat pipes; the structural support and deployment energy is provided using tape-spring hinges. The FETS is a novel combination of existing technologies. Prior art for deployable heat shields uses rotating hinges that typically must be lubricated to avoid cold welding or static friction. By using tape-spring hinges, the FETS avoids the need for lubricants by avoiding friction altogether. This also eliminates the potential for contamination of nearby cooled optics by outgassing lubricants. Furthermore, the tape-spring design of the FETS is also self-locking so the panels stay in a rigid and extended configuration after deployment. This unexpected benefit makes the tape-spring hinge design of the FETS a light, simple, reliable, compact, non-outgassing hinge, spring, and latch. While tape-spring hinges are not novel, they have never been used to deploy passive unfolding thermal surfaces (radiator panels, covers, sun shades, or IR thermal shields). Furthermore, because this technology is compact, it has minimal impact on the launch envelope and mass specifications. FETS enhances the performance of hosted payload instruments where the science data is limited by dark noise. Incorporating FETS into a thermal control system increases radiator area, which lowers the optical detector temperature. This results in higher SNR (signal-to-noise ratio) and improved science data.

The Evaluation of the Safety Benefits of Combined Passive and On-Board Active Safety Applications

PubMed Central

Page, Yves; Cuny, Sophie; Zangmeister, Tobias; Kreiss, Jens-Peter; Hermitte, Thierry

2009-01-01

One of the objectives of the European TRACE project (TRaffic Accident Causation in Europe, 2006–2008) was to estimate the proportion of injury accidents that could be avoided and/or the proportion of injury accidents where the severity could be mitigated for on-the-market safety applications, if 100 % of the car fleet would be equipped with them. We have selected for evaluation the Electronic Stability Control (ESC) and the Emergency Brake Assist (EBA) applications. As for passive safety systems, recent cars are designed to offer overall safety protection. Car structure, load limiters, front airbags, side airbags, knee airbags, pretensioners, padding and non aggressive structures in the door panel, the dashboard, the windshield, the seats, and the head rest also contribute to applying more protection. The whole safety package is very difficult to evaluate separately, one element independently segmented from the others. We decided to consider evaluating the effectivenessof the whole passive safety package, This package,, for the sake of simplicity, was the number of stars awarded at the Euro NCAP testing. The challenges were to compare the effectiveness of some safety configuration SC I, with the effectiveness of a different safety configuration SC II. A safety configuration is understood as a package of safety functions. Ten comparisons have been carried out such as the evaluation of the safety benefit of a fifth star given that the car has four stars and an EBA. The main outcome of this analysis is that any addition of a passive or active safety function selected in this analysis is producing increased safety benefits. For example, if all cars were five stars fitted with EBA and ESC, instead of four stars without ESC and EBA, injury accidents would be reduced by 47.2% for severe injuries and 69.5% for fatal injuries. PMID:20184838

Integration of Active and Passive Safety Technologies--A Method to Study and Estimate Field Capability.

PubMed

Hu, Jingwen; Flannagan, Carol A; Bao, Shan; McCoy, Robert W; Siasoco, Kevin M; Barbat, Saeed

2015-11-01

The objective of this study is to develop a method that uses a combination of field data analysis, naturalistic driving data analysis, and computational simulations to explore the potential injury reduction capabilities of integrating passive and active safety systems in frontal impact conditions. For the purposes of this study, the active safety system is actually a driver assist (DA) feature that has the potential to reduce delta-V prior to a crash, in frontal or other crash scenarios. A field data analysis was first conducted to estimate the delta-V distribution change based on an assumption of 20% crash avoidance resulting from a pre-crash braking DA feature. Analysis of changes in driver head location during 470 hard braking events in a naturalistic driving study found that drivers' head positions were mostly in the center position before the braking onset, while the percentage of time drivers leaning forward or backward increased significantly after the braking onset. Parametric studies with a total of 4800 MADYMO simulations showed that both delta-V and occupant pre-crash posture had pronounced effects on occupant injury risks and on the optimal restraint designs. By combining the results for the delta-V and head position distribution changes, a weighted average of injury risk reduction of 17% and 48% was predicted by the 50th percentile Anthropomorphic Test Device (ATD) model and human body model, respectively, with the assumption that the restraint system can adapt to the specific delta-V and pre-crash posture. This study demonstrated the potential for further reducing occupant injury risk in frontal crashes by the integration of a passive safety system with a DA feature. Future analyses considering more vehicle models, various crash conditions, and variations of occupant characteristics, such as age, gender, weight, and height, are necessary to further investigate the potential capability of integrating passive and DA or active safety systems.

A symmetrical method to obtain shear moduli from microrheology† †Electronic supplementary information (ESI) available. See DOI: 10.1039/c7sm02499a

PubMed Central

Nishi, Kengo

2018-01-01

Passive microrheology typically deduces shear elastic loss and storage moduli from displacement time series or mean-squared displacements (MSD) of thermally fluctuating probe particles in equilibrium materials. Common data analysis methods use either Kramers–Kronig (KK) transformation or functional fitting to calculate frequency-dependent loss and storage moduli. We propose a new analysis method for passive microrheology that avoids the limitations of both of these approaches. In this method, we determine both real and imaginary components of the complex, frequency-dependent response function χ(ω) = χ′(ω) + iχ′′(ω) as direct integral transforms of the MSD of thermal particle motion. This procedure significantly improves the high-frequency fidelity of χ(ω) relative to the use of KK transformation, which has been shown to lead to artifacts in χ′(ω). We test our method on both model and experimental data. Experiments were performed on solutions of worm-like micelles and dilute collagen solutions. While the present method agrees well with established KK-based methods at low frequencies, we demonstrate significant improvement at high frequencies using our symmetric analysis method, up to almost the fundamental Nyquist limit. PMID:29611576

A minimalist approach to bias estimation for passive sensor measurements with targets of opportunity

NASA Astrophysics Data System (ADS)

Belfadel, Djedjiga; Osborne, Richard W.; Bar-Shalom, Yaakov

2013-09-01

In order to carry out data fusion, registration error correction is crucial in multisensor systems. This requires estimation of the sensor measurement biases. It is important to correct for these bias errors so that the multiple sensor measurements and/or tracks can be referenced as accurately as possible to a common tracking coordinate system. This paper provides a solution for bias estimation for the minimum number of passive sensors (two), when only targets of opportunity are available. The sensor measurements are assumed time-coincident (synchronous) and perfectly associated. Since these sensors provide only line of sight (LOS) measurements, the formation of a single composite Cartesian measurement obtained from fusing the LOS measurements from different sensors is needed to avoid the need for nonlinear filtering. We evaluate the Cramer-Rao Lower Bound (CRLB) on the covariance of the bias estimate, i.e., the quantification of the available information about the biases. Statistical tests on the results of simulations show that this method is statistically efficient, even for small sample sizes (as few as two sensors and six points on the trajectory of a single target of opportunity). We also show that the RMS position error is significantly improved with bias estimation compared with the target position estimation using the original biased measurements.

Active/passive scanning. [airborne multispectral laser scanners for agricultural and water resources applications

NASA Technical Reports Server (NTRS)

Woodfill, J. R.; Thomson, F. J.

1979-01-01

The paper deals with the design, construction, and applications of an active/passive multispectral scanner combining lasers with conventional passive remote sensors. An application investigation was first undertaken to identify remote sensing applications where active/passive scanners (APS) would provide improvement over current means. Calibration techniques and instrument sensitivity are evaluated to provide predictions of the APS's capability to meet user needs. A preliminary instrument design was developed from the initial conceptual scheme. A design review settled the issues of worthwhile applications, calibration approach, hardware design, and laser complement. Next, a detailed mechanical design was drafted and construction of the APS commenced. The completed APS was tested and calibrated in the laboratory, then installed in a C-47 aircraft and ground tested. Several flight tests completed the test program.

Airborne Remote Observations of L-Band Radio Frequency Interference and Implications for Satellite Missions

NASA Technical Reports Server (NTRS)

Laymon, Charles; Srinivasan, Karthik; Limaye, Ashutosh

2011-01-01

Passive remote sensing of the Earth s surface and atmosphere from space has significant importance in operational and research environmental studies, in particular for the scientific understanding, monitoring and prediction of climate change and its impacts. Passive remote sensing requires the measurement of naturally occurring radiations, usually of very low power levels, which contain essential information on the physical process under investigation. As such, these sensed radio frequency bands are a unique natural resource enabling space borne passive sensing of the atmosphere and the Earth s surface that deserves adequate allocation to the Earth Exploration Satellite Service and absolute protection from interference. Unfortunately, radio frequency interference (RFI) is an increasing problem for Earth remote sensing, particularly for passive observations of natural emissions. Because these natural signals tend to be very weak, even low levels of interference received by a passive sensor may degrade the fidelity of scientific data. The characteristics of RFI (low-level interference and radar-pulse noise) are not well known because there has been no systematic surveillance, spectrum inventory or mapping of RFI. While conducting a flight experiment over central Tennessee in May 2010, RFI, a concern for any instrument operating in the passive L band frequency, was observed across 16 subbands between 1402-1427 MHz. Such a survey provides rare characterization data from which to further develop mitigation technologies as well as to identify bandwidths to avoid in future sensor formulation.

Independent and joint exposure to passive smoking and cooking oil fumes on oral cancer in Chinese women: a hospital-based case-control study.

PubMed

He, Baochang; Chen, Fa; Yan, Lingjun; Huang, Jiangfeng; Liu, Fangping; Qiu, Yu; Lin, Lisong; Zhang, Zuofeng; Cai, Lin

2016-10-01

Passive smoking and COF exposure are independent risk factors for oral cancer in Chinese women, with the multiplicative interactions from combined exposures. Avoiding exposure to environmental tobacco smoke and COF may contribute to the prevention of oral cancer in Chinese women. To evaluate the independent and joint effects of passive smoking and cooking oil fumes (COF) on oral cancer in Chinese women. A case-control study was performed including 238 female patients with pathologically confirmed oral cancer and 470 controls as age-matched controls. Face-to-face interviews were conducted based on a structured questionnaire. The effects of passive smoking and COF exposure were analyzed using non-conditional logistic regression models. Passive smoking significantly increased the risk of oral cancer in Chinese women: adjusted ORs were 2.12 (95% CI = 1.11-4.07) for those only exposed before age 18, 1.52 (95% CI = 1.01-2.31) for those only exposed after age 18, and 2.38 (95% CI = 1.47-3.85) for those both exposed before and after age 18. In addition, COF exposure was significantly associated with a risk of oral cancer (adjusted ORs were 1.69 (95% CI = 1.03-2.78) for light exposure and 2.06 (95% CI = 1.21-3.50) for heavy exposure). Furthermore, there was a significantly multiplicative interaction between passive smoking and COF for oral cancer.

Enhancing hazard avoidance in teen-novice riders.

PubMed

Vidotto, Giulio; Bastianelli, Alessia; Spoto, Andrea; Sergeys, Filip

2011-01-01

Research suggests that novice drivers' safety performance is inferior to that of experienced drivers in different ways. One of the most critical skills related to accident avoidance by a novice driver is the detection, recognition and reaction to traffic hazards; it is called hazard perception and is defined as the ability to identify potentially dangerous traffic situations. The focus of this research is to assess how far a motorcycle simulator could improve hazard avoidance skills in teenagers. Four hundred and ten participants (207 in the experimental group and 203 in the control group) took part in this research. Results demonstrated that the mean proportion of avoided hazards increases as a function of the number of tracks performed in the virtual training. Participants of the experimental group after the training had a better proportion of avoided hazards than participants of the control group with a passive training based on a road safety lesson. Results provide good evidence that training with the simulator increases the number of avoided accidents in the virtual environment. It would be reasonable to explain this improvement by a higher level of hazard perception skills. Copyright © 2010 Elsevier Ltd. All rights reserved.

A self-regulation perspective on avoidance and persistence behavior in chronic pain: new theories, new challenges?

PubMed

Van Damme, Stefaan; Kindermans, Hanne

2015-02-01

Behavioral factors such as avoidance and persistence have received massive theoretical and empirical attention in the attempts to explain chronic pain and disability. The determinants of these pain behaviors remain, however, poorly understood. We propose a self-regulation perspective to increase our understanding of pain-related avoidance and persistence. A narrative review. We identified several theoretical views that may help explaining avoidance and persistence behavior, and organized these views around 4 concepts central in self-regulation theories: (1) identity, (2) affective-motivational orientation, (3) goal cognitions, and (4) coping. The review shows that each of these self-regulation perspectives allows for a broadened view in which pain behaviors are not simply considered passive consequences of fear, but proactive strategies to regulate the self when challenged by pain. Several implications and challenges arising from this review are discussed. In particular, a self-regulation perspective does not consider avoidance and persistence behavior to be intrinsically adaptive or maladaptive, but argues that their effects on disability and well-being rather depend on the goals underlying these behaviors. Such view would require a shift in how avoidance and persistence behavior are assessed and approached in clinical interventions.

Proline-containing dipeptide GVS-111 retains nootropic activity after oral administration.

PubMed

Ostrovskaya, R U; Mirsoev, T K; Romanova, G A; Gudasheva, T A; Kravchenko, E V; Trofimov, C C; Voronina, T A; Seredenin, S B

2001-10-01

Experiments on rats trained passive avoidance task showed that N-phenyl-acetyl-L-prolyl-glycyl ethyl ester, peptide analog of piracetam (GVS-111, Noopept) after oral administration retained antiamnesic activity previously observed after its parenteral administration. Effective doses were 0.5-10 mg/kg. Experiments on a specially-developed model of active avoidance (massive one-session learning schedule) showed that GVS-111 stimulated one-session learning after single administration, while after repeated administration it increased the number of successful learners among those animals who failed after initial training. In this respect, GVS-111 principally differs from its main metabolite cycloprolylglycine and standard nootropic piracetam.

Developing Coping Typologies of Minority Adolescents: A Latent Profile Analysis

PubMed Central

Aldridge, Arianna A.; Roesch, Scott C.

2008-01-01

Latent profile analysis (LPA) was used to develop a coping typology of minority adolescents (M = 15.5 yrs). A multiethnic sample (n = 354) was recruited from a program aimed at serving low-income students. LPA revealed three distinct coping profiles. The first comprised adolescents who used a number of specific coping strategies at a low level (Low Generic Copers). The second comprised adolescents who emphasized active/approach strategies (e.g., planning; Active Copers). The third comprised adolescents who emphasized avoidant/passive strategies (e.g., substance abuse; Avoidant Copers). Active Copers experienced significantly less depression and more stress-related growth than Low Generic Copers. Low Generic Copers experienced significantly less depression than Avoidant Copers but also significantly less stress-related growth than Active Copers. Discussion focuses on integrating the current typology with traditional coping taxomonies. PMID:17904631

Passivity of the bars manufactured using current technologies: laser-sintering, casting, and milling

NASA Astrophysics Data System (ADS)

Popescu, Diana; Popescu, Sabin; Pop, Daniel; Jivanescu, Anca; Todea, Carmen

2014-01-01

Implant overdentures are often selected as therapeutic options for the treatment of edentulous mandibles. "Passive-fit" between the mesostructures and the implants plays an important role in the longevity of the implant-prosthetic assembly in the oral cavity. "Mis-fit" can cause mechanical or biological complications. The purpose of this test was to investigate the passive adaptation of the bars manufactured through different technologies, and in this respect two bars (short and long) were fabricated by each process: laser-sintering, milling, casting. The tensions induced by tightening the connection screw between the bars and the underlying implants were recorded using strain gauges and used as measuring and comparing tool in testing the bars' "passivity". The results of the test showed that the milled bars had the best "passive-fit", followed by laser-sintered bars, while cast bars had the lowest adaptation level.

Coping and sickness absence

PubMed Central

Schaufeli, Wilmar B.; van Dijk, Frank J. H.; Blonk, Roland W. B.

2007-01-01

Objectives The aim of this study is to examine the role of coping styles in sickness absence. In line with findings that contrast the reactive–passive focused strategies, problem-solving strategies are generally associated with positive results in terms of well-being and overall health outcomes; our hypothesis is that such strategies are positively related to a low frequency of sickness absence and with short lengths (total number of days absent) and durations (mean duration per spell). Methods Using a prospective design, employees’ (N = 3,628) responses on a self-report coping inventory are used to predict future registered sickness absence (i.e. frequency, length, duration, and median time before the onset of a new sick leave period). Results and conclusions In accordance with our hypothesis, and after adjustment for potential confounders, employees with an active problem-solving coping strategy are less likely to drop out because of sickness absence in terms of frequency, length (longer than 14 days), and duration (more than 7 days) of sickness absence. This positive effect is observed in the case of seeking social support only for the duration of sickness absence and in the case of palliative reaction only for the length and frequency of absence. In contrast, an avoidant coping style, representing a reactive–passive strategy, increases the likelihood of frequent absences significantly, as well as the length and duration of sickness absence. Expression of emotions, representing another reactive–passive strategy, has no effect on future sickness absenteeism. The median time before the onset of a new episode of absenteeism is significantly extended for active problem-solving and reduced for avoidance and for a palliative response. The results of the present study support the notion that problem-solving coping and reactive–passive strategies are inextricably connected to frequency, duration, length and onset of sickness absence. Especially, active problem-solving decreases the chance of future sickness absence. PMID:17701200

Coping and sickness absence.

PubMed

van Rhenen, Willem; Schaufeli, Wilmar B; van Dijk, Frank J H; Blonk, Roland W B

2008-02-01

The aim of this study is to examine the role of coping styles in sickness absence. In line with findings that contrast the reactive-passive focused strategies, problem-solving strategies are generally associated with positive results in terms of well-being and overall health outcomes; our hypothesis is that such strategies are positively related to a low frequency of sickness absence and with short lengths (total number of days absent) and durations (mean duration per spell). Using a prospective design, employees' (N = 3,628) responses on a self-report coping inventory are used to predict future registered sickness absence (i.e. frequency, length, duration, and median time before the onset of a new sick leave period). In accordance with our hypothesis, and after adjustment for potential confounders, employees with an active problem-solving coping strategy are less likely to drop out because of sickness absence in terms of frequency, length (longer than 14 days), and duration (more than 7 days) of sickness absence. This positive effect is observed in the case of seeking social support only for the duration of sickness absence and in the case of palliative reaction only for the length and frequency of absence. In contrast, an avoidant coping style, representing a reactive-passive strategy, increases the likelihood of frequent absences significantly, as well as the length and duration of sickness absence. Expression of emotions, representing another reactive-passive strategy, has no effect on future sickness absenteeism. The median time before the onset of a new episode of absenteeism is significantly extended for active problem-solving and reduced for avoidance and for a palliative response. The results of the present study support the notion that problem-solving coping and reactive-passive strategies are inextricably connected to frequency, duration, length and onset of sickness absence. Especially, active problem-solving decreases the chance of future sickness absence.

Enhanced anandamide signaling reduces flight behavior elicited by an approaching robo-beetle.

PubMed

Heinz, Daniel E; Genewsky, Andreas; Wotjak, Carsten T

2017-11-01

Our current knowledge of the implications of endocannabinoids in fear and anxiety is largely based on fear conditioning paradigms and approach-avoidance conflicts. Here we establish the ethobehavioral beetle mania task (BMT), which confronts mice with an erratically moving robo-beetle. With the help of this task we demonstrate decreased tolerance yet increased avoidance responses to an approaching beetle in high-anxiety behavior (HAB) and BALBc mice compared to C57BL/6N, CD1 and normal-anxiety behavior (NAB) mice. Also DBA/2N mice showed decreased passive and increased active behavior, but followed the robo-beetle more often than HAB and BALBc mice. Treatment with diazepam (1 mg/kg) increased tolerance without affecting avoidance behavior in HAB mice. Treatment with the MAGL inhibitor JZL184 (8 mg/kg) increased flight behavior, but did not affect tolerance. The FAAH inhibitor URB597 (0.3 mg/kg), however, reduced flight behavior and enhanced tolerance to the robo-beetle. The latter effects were blocked by co-treatment with the CB1 receptor antagonist SR141716A (3 mg/kg), which failed to affect the behavior by itself. Taken together, we validate the BMT as a novel test for studying endocannabinoids beyond traditional paradigms and for assessing active fear responses in mice. Furthermore, we demonstrate panicolytic consequences of pharmacological enhancement of anandamide, but not 2-AG signaling. Copyright © 2017 Elsevier Ltd. All rights reserved.

Developing a Passive Acoustic Monitoring Network for Harbor Porpoise in California

NASA Astrophysics Data System (ADS)

Jacobson, Eiren Kate

Assessing the abundance of and trends in whale, dolphin, and porpoise (cetacean) populations using traditional visual methods can be challenging due primarily to their limited availability at the surface of the ocean. As a result, researchers are increasingly interested in incorporating non-visual and remote observations to improve cetacean population assessments. Passive acoustic monitoring (PAM) can complement or replace visual surveys for cetaceans that produce echolocation clicks, whistles, and other vocalizations. My doctoral dissertation is focused on developing methods to improve PAM of cetaceans. I used the Monterey Bay population of harbor porpoise (Phocoena phocoena ) as a case study for methods development. In Chapter 2, I used passive acoustic data to document that harbor porpoises avoid bottlenose dolphins (Tursiops truncatus) in nearshore Monterey Bay. In Chapter 3, I investigated whether different passive acoustic instruments could be used to monitor harbor porpoise. I recorded harbor porpoise echolocation clicks simultaneously on two different passive acoustic instruments and compared the number and peak frequency of echolocation signals recorded on the two instruments. I found that the number of echolocation clicks was highly correlated between instruments but that the peak frequency of echolocation clicks was not well-correlated, suggesting that some instruments may not be capable of discriminating harbor porpoise echolocation clicks in regions where multiple species with similar echolocation signals are present. In Chapter 4, I used paired visual and passive acoustic surveys to estimate the effective detection area of the passive acoustic sensors in a Bayesian framework. This approach resulted in a posterior distribution of the effective detection area that was consistent with previously published values. In Chapter 5, I used aerial survey and passive acoustic data in a simulation framework to investigate the statistical power of different passive acoustic network designs and hypothetical changes in harbor porpoise abundance. As a whole, this dissertation used an applied approach to methods development to advance the use of PAM for cetaceans.

Anticonvulsant and psychomotor activity of nitrendipine alone and in combination with phenytoin and valproate in rats.

PubMed

Balakrishnan, S; Bhargava, V K; Pandhi, P

1999-01-01

The effect of nitrendipine (NTP) alone and in combination with phenytoin (PHT) and valproate (VPA) against maximal electroshock seizures (MES) was studied in rats. In addition, the psychomotor effects of NTP alone and in combination with PHT and VPA were evaluated using the following tests: a) rotarod performance; b) spontaneous motor activity; c) despair behavior; d) righting reflex; e) hole board test; and f) passive avoidance test. ED50 values of PHT, VPA and NTP were 13,255 and 3.6 mg/kg, respectively. When NTP was combined with PHT or VPA, the ED50 values decreased to 0.9 and 226 mg/kg, respectively. In the psychomotor function tests, for the same degree of protection (50%) afforded against MES, PHT or VPA produced a greater impairment in all the parameters compared to NTP alone or a combination of NTP with PHT or VPA. Furthermore, NTP reversed the depression and long-term memory loss induced by PHT and VPA. Thus, NTP was effective against MES in rats, potentiating the anti-electroshock activity of PHT and VPA and producing less impairment of psychomotor activity. Thus, the agent can be considered a potential antiepileptic warranting further studies.

COBALT: A GN&C Payload for Testing ALHAT Capabilities in Closed-Loop Terrestrial Rocket Flights

NASA Technical Reports Server (NTRS)

Carson, John M., III; Amzajerdian, Farzin; Hines, Glenn D.; O'Neal, Travis V.; Robertson, Edward A.; Seubert, Carl; Trawny, Nikolas

2016-01-01

The COBALT (CoOperative Blending of Autonomous Landing Technology) payload is being developed within NASA as a risk reduction activity to mature, integrate and test ALHAT (Autonomous precision Landing and Hazard Avoidance Technology) systems targeted for infusion into near-term robotic and future human space flight missions. The initial COBALT payload instantiation is integrating the third-generation ALHAT Navigation Doppler Lidar (NDL) sensor, for ultra high-precision velocity plus range measurements, with the passive-optical Lander Vision System (LVS) that provides Terrain Relative Navigation (TRN) global-position estimates. The COBALT payload will be integrated onboard a rocket-propulsive terrestrial testbed and will provide precise navigation estimates and guidance planning during two flight test campaigns in 2017 (one open-loop and closed- loop). The NDL is targeting performance capabilities desired for future Mars and Moon Entry, Descent and Landing (EDL). The LVS is already baselined for TRN on the Mars 2020 robotic lander mission. The COBALT platform will provide NASA with a new risk-reduction capability to test integrated EDL Guidance, Navigation and Control (GN&C) components in closed-loop flight demonstrations prior to the actual mission EDL.

Spiny lobsters detect conspecific blood-borne alarm cues exclusively through olfactory sensilla.

PubMed

Shabani, Shkelzen; Kamio, Michiya; Derby, Charles D

2008-08-01

When attacked by predators, diverse animals actively or passively release molecules that evoke alarm and related anti-predatory behavior by nearby conspecifics. The actively released molecules are alarm pheromones, whereas the passively released molecules are alarm cues. For example, many insects have alarm-signaling systems that involve active release of alarm pheromones from specialized glands and detection of these signals using specific sensors. Many crustaceans passively release alarm cues, but the nature of the cues, sensors and responses is poorly characterized. Here we show in laboratory and field experiments that injured Caribbean spiny lobsters, Panulirus argus, passively release alarm cues via blood (hemolymph) that induce alarm responses in the form of avoidance and suppression of feeding. These cues are detected exclusively through specific olfactory chemosensors, the aesthetasc sensilla. The alarm cues for Caribbean spiny lobsters are not unique to the species but do show some phylogenetic specificity: P. argus responds primarily with alarm behavior to conspecific blood, but with mixed alarm and appetitive behaviors to blood from the congener Panulirus interruptus, or with appetitive behaviors to blood from the blue crab Callinectes sapidus. This study lays the foundation for future neuroethological studies of alarm cue systems in this and other decapod crustaceans.

Passive and Active Control of Space Structures (PACOSS)

NASA Astrophysics Data System (ADS)

Morosow, G.; Harcrow, H.; Rogers, L.

1985-04-01

Passive and Active Control of Space Structures (PACOSS) is a five-year program designed to investigate highly damped structures in conjunction with active control systems, and in particular to develop technology that integrates passive damping and active control to achieve precise pointing control. Major areas of research include metal matrix composites; viscoelastic materials; damping devices; dynamic test article design, fabrication and testing; and active damping.

Development of amnesia in different mouse strains.

PubMed

Sinovyev, D R; Dubrovina, N I; Kulikov, A V

2009-05-01

We studied passive avoidance retrieval after amnestic stimulation (arrest in unsafe section of the experimental setup) in C57Bl/6J, BALB/c, CBA/Lac, AKR/J, DBA/2J, C3H/HeJ, and ASC/Icg mice. We demonstrated resistance to amnestic stimulation in mice with high predisposition to freezing reaction (ASC/Icg) and memory deficit in other mouse strains.

Learning and memory deficits in mice lacking protease activated receptor-1

PubMed Central

Almonte, Antoine G.; Hamill, Cecily E.; Chhatwal, Jasmeer P.; Wingo, Thomas S.; Barber, Jeremy A.; Lyuboslavsky, Polina N.; Sweatt, J. David; Ressler, Kerry J.; White, David A.; Traynelis, Stephen F.

2007-01-01

The roles of serine proteases and protease activated receptors have been extensively studied in coagulation, wound healing, inflammation, and neurodegeneration. More recently, serine proteases have been suggested to influence synaptic plasticity. In this context, we examined the role of protease activated receptor 1 (PAR1), which is activated following proteolytic cleavage by thrombin and plasmin, in emotionally-motivated learning. We were particularly interested in PAR1 because its activation enhances the function of NMDA receptors, which are required for some forms of synaptic plasticity. We examined several baseline behavioral measures, including locomotor activity, expression of anxiety-like behavior, motor task acquisition, nociceptive responses, and startle responses in C57Bl/6 mice in which the PAR1 receptor has been genetically deleted. In addition, we evaluated learning and memory in these mice using two memory tasks, passive avoidance and cued fear-conditioning. Whereas locomotion, pain response, startle, and measures of baseline anxiety were largely unaffected by PAR1 removal, PAR1−/− animals showed significant deficits in a passive avoidance task and in cued fear conditioning. These data suggest that PAR1 may play an important role in emotionally-motivated learning. PMID:17544303

[Influence of stimulation and blockade of α4β2 nicotinic acetylcholine receptors on learning of female rats in basic phases of ovary cycle].

PubMed

Fedotova, Iu O

2014-03-01

The present work was devoted to the comparative analysis of α4β2 nicotinic acetylcholine receptors (nAChRs) in learning/memory processes during ovary cycle in the adult female rats. RJR-2403 (1.0 mg/kg, i. p.), α4β2 nAChRs agonist and mecamylamine (1.0 mg/kg, i. p.), α4β2 nAChRs antagonist were injected chronically during 14 days. The processes of learning/memory were assessed in different models of learning: passive avoidance performance and Morris water maze. Chronic RJR-2403 administration to females improved the passive avoidance performance in proestrous and estrous as compared to the control animals. Also, RJR-2403 restored spatial learning of rats during proestrous phases in Morris water maze, and stimulated the dynamics of spatial learning during estrous phases. On the contrary, the chronic mecamylamine administration impaired non-spatial, and especially, spatial learning in females during key phases of ovary cycle. The results of the study suggest positive effect of α4β2 nAChRs stimulation in learning/memory processes during ovary cycle in the adult female rats.

The effect of sleep deprivation on leadership behaviour in military officers: an experimental study.

PubMed

Olsen, Olav Kjellevold; Pallesen, Ståle; Torsheim, Torbjørn; Espevik, Roar

2016-12-01

While several studies show that leaders frequently lack sleep, little is known about how this influences leadership behaviour. The present study encompasses an experiment that investigated how three main types of leadership behaviour: transformational (four sub-facets); transactional (two sub-facets); and passive-avoidant (two sub-facets) leadership differed across a rested and a long-term, partially sleep-deprived condition. A total of 16 military naval officers participated. In both conditions, the leaders managed a team of three subordinates in a navy navigation simulator, instructed to complete a specific mission (A or B). Both sleep state (rested or sleep deprived) and mission were counterbalanced. Leadership behaviour was video recorded and subsequently rated on the three leadership behaviours. Overall, the scores on transformational leadership (and on two of four sub-facets) and transactional leadership (on both sub-facets) decreased from the rested to sleep-deprived condition, whereas scores on passive-avoidant leadership overall (and on both sub-facets) increased from the rested to sleep-deprived condition. This study underscores the importance of including sleep as a potentially important determinant when assessing leadership effectiveness. © 2016 European Sleep Research Society.

Passivity-based control with collision avoidance for a hub-beam spacecraft

NASA Astrophysics Data System (ADS)

Wen, Hao; Chen, Ti; Jin, Dongping; Hu, Haiyan

2017-01-01

For the application of robotically assembling large space structures, a feedback control law is synthesized for transitional and rotational maneuvers of a 'tug' spacecraft in order to transport a flexible element to a desired position without colliding with other space bodies. The flexible element is treated as a long beam clamped to the 'tug' spacecraft modelled as a rigid hub. First, the physical property of passivity of Euler-Lagrange system is exploited to design the position and attitude controllers by taking a simpler obstacle-free control problem into account. To reduce sensing and actuating requirements, the vibration modes of the beam appendage are supposed to be not directly measured and actuated on. Besides, the requirements of measuring velocities are removed with the aid of a dynamic extension technique. Second, the bounding boxes in the form of super-quadric surfaces are exploited to enclose the maximal extents of the obstacles and the hub-beam spacecraft. The collision avoidance between bounding boxes is achieved by applying additional repulsive force and torque to the spacecraft based on the method of artificial potential field. Finally, the effectiveness of proposed control scheme is numerically demonstrated via case studies.

The passive hamstring stretch test: clinical evaluation.

PubMed

Fisk, J W

1979-03-28

The passive hamstring stretch test is described. Using a modified goniometer it is shown that independent measurements taken by trained examiners approximate very closely to each other. This establishes the test as a valid objective measurement. The possible value of this test as a research tool in low back pain problems is discussed.

The Passive in 3- and 4-Year-Olds

ERIC Educational Resources Information Center

de Barros Pereira Rubin, Maraci Coelho

2009-01-01

This paper argues that analyzing the patterns of individual subject performance in tests of comprehension of passives might give insight into how little children interpret passives: 3 and 4 year-olds seem to go through a range of passive interpretation, that varies from actual comprehension to total non-comprehension. The fact that some small…

Demonstration of Passive Fuel Cell Thermal Management Technology

NASA Technical Reports Server (NTRS)

Burke, Kenneth A.; Jakupca, Ian; Colozza, Anthony; Wynne, Robert; Miller, Michael; Meyer, Al; Smith, William

2012-01-01

The NASA Glenn Research Center is developing advanced passive thermal management technology to reduce the mass and improve the reliability of space fuel cell systems for the NASA Exploration program. The passive thermal management system relies on heat conduction within highly thermally conductive cooling plates to move the heat from the central portion of the cell stack out to the edges of the fuel cell stack. Using the passive approach eliminates the need for a coolant pump and other cooling loop components within the fuel cell system which reduces mass and improves overall system reliability. Previous development demonstrated the performance of suitable highly thermally conductive cooling plates and integrated heat exchanger technology to collect the heat from the cooling plates (Ref. 1). The next step in the development of this passive thermal approach was the demonstration of the control of the heat removal process and the demonstration of the passive thermal control technology in actual fuel cell stacks. Tests were run with a simulated fuel cell stack passive thermal management system outfitted with passive cooling plates, an integrated heat exchanger and two types of cooling flow control valves. The tests were run to demonstrate the controllability of the passive thermal control approach. Finally, successful demonstrations of passive thermal control technology were conducted with fuel cell stacks from two fuel cell stack vendors.

Is Free Recall Active: The Testing Effect through the ICAP Lens

ERIC Educational Resources Information Center

Bruchok, Christiana; Mar, Christopher; Craig, Scotty D.

2017-01-01

Amidst evidence in favor of "active learning," online instruction widely implements passive design and tests learners' retrieval performance as opposed to learners' understanding. Literature reporting the testing effect promotes recall as a learning tool. The Interactive>Constructive>Active>Passive taxonomy would place quizzing…

Semiconductor with protective surface coating and method of manufacture thereof. [Patent application

DOEpatents

Hansen, W.L.; Haller, E.E.

1980-09-19

Passivation of predominantly crystalline semiconductor devices is provided for by a surface coating of sputtered hydrogenated amorphous semiconductor material. Passivation of a radiation detector germanium diode, for example, is realized by sputtering a coating of amorphous germanium onto the etched and quenched diode surface in a low pressure atmosphere of hydrogen and argon. Unlike prior germanium diode semiconductor devices, which must be maintained in vacuum at cryogenic temperatures to avoid deterioration, a diode processed in the described manner may be stored in air at room temperature or otherwise exposed to a variety of environmental conditions. The coating compensates for pre-existing undesirable surface states as well as protecting the semiconductor device against future impregnation with impurities.

Dynamical thermal effects in InGaAsP microtubes at telecom wavelengths.

PubMed

Tian, Zhaobing; Bianucci, Pablo; Roche, Philip J R; Dastjerdi, M Hadi Tavakoli; Mi, Zetian; Poole, Philip J; Kirk, Andrew G; Plant, David V

2012-07-01

We report on the observation of a dynamical thermal effect in InGaAsP microtubes at telecom wavelengths. The microtubes are fabricated by releasing a strained semiconductor bilayer and are picked up by abruptly tapered optical fibers for subsequent coupling with adiabatically tapered optical fibers. As a result of absorption by InAs quantum dots embedded in the tube structure, these microtubes show dynamical thermal effects at wavelengths around 1525 nm and 1578 nm, while they are passive at longer wavelengths near 1634 nm. The photon absorption induced thermal effect is visualized by generating a pair of microbottles. The dynamical thermal effect can be avoided or exploited for passive or active applications by utilizing appropriate resonance wavelengths.

New PANDA Tests to Investigate Effects of Light Gases on Passive Safety Systems

DOE Office of Scientific and Technical Information (OSTI.GOV)

Paladino, D.; Auban, O.; Candreia, P.

The large- scale thermal-hydraulic PANDA facility (located at PSI in Switzerland), has been used over the last few years for investigating different passive decay- heat removal systems and containment phenomena for the next generation of light water reactors (Simplified Boiling Water Reactor: SBWR; European Simplified Boiling Water Reactor: ESBWR; Siedewasserreaktor: SWR-1000). Currently, as part of the European Commission 5. EURATOM Framework Programme project 'Testing and Enhanced Modelling of Passive Evolutionary Systems Technology for Containment Cooling' (TEMPEST), a new series of tests is being planned in the PANDA facility to experimentally investigate the distribution of non-condensable gases inside the containment andmore » their effect on the performance of the 'Passive Containment Cooling System' (PCCS). Hydrogen release caused by the metal-water reaction in the case of a postulated severe accident will be simulated in PANDA by injecting helium into the reactor pressure vessel. In order to provide suitable data for Computational Fluid Dynamic (CFD) code assessment and improvement, the instrumentation in PANDA has been upgraded for the new tests. In the present paper, a detailed discussion is given of the new PANDA tests to be performed to investigate the effects of light gas on passive safety systems. The tests are scheduled for the first half of the year 2002. (authors)« less

Abnormalities in brain structure and behavior in GSK-3alpha mutant mice

PubMed Central

2009-01-01

Background Glycogen synthase kinase-3 (GSK-3) is a widely expressed and highly conserved serine/threonine protein kinase encoded by two genes that generate two related proteins: GSK-3α and GSK-3β. Mice lacking a functional GSK-3α gene were engineered in our laboratory; they are viable and display insulin sensitivity. In this study, we have characterized brain functions of GSK-3α KO mice by using a well-established battery of behavioral tests together with neurochemical and neuroanatomical analysis. Results Similar to the previously described behaviours of GSK-3β+/-mice, GSK-3α mutants display decreased exploratory activity, decreased immobility time and reduced aggressive behavior. However, genetic inactivation of the GSK-3α gene was associated with: decreased locomotion and impaired motor coordination, increased grooming activity, loss of social motivation and novelty; enhanced sensorimotor gating and impaired associated memory and coordination. GSK-3α KO mice exhibited a deficit in fear conditioning, however memory formation as assessed by a passive avoidance test was normal, suggesting that the animals are sensitized for active avoidance of a highly aversive stimulus in the fear-conditioning paradigm. Changes in cerebellar structure and function were observed in mutant mice along with a significant decrease of the number and size of Purkinje cells. Conclusion Taken together, these data support a role for the GSK-3α gene in CNS functioning and possible involvement in the development of psychiatric disorders. PMID:19925672

The effects of passive stretching plus vibration on strength and activation of the plantar flexors.

PubMed

Miller, Jonathan D; Herda, Trent J; Trevino, Michael A; Mosier, Eric M

2016-09-01

This study examined the effects of passive stretching only (PS+CON) and passive stretching with the addition of continuous vibration (VIB) during post-passive stretching tests (PS+VIB) on peak torque (PT), percent voluntary inactivation (%VI), single stimulus twitch torque (TTSINGLE), and doublet stimuli twitch torque (TTDOUBLET) of the plantar flexors at a short (20° plantar flexion (PF)) and long muscle length (15° dorsiflexion (DF)). Fourteen healthy men (age = 22 ± 3 years) performed isometric maximal voluntary contractions at PF and DF, and passive range of motion (PROM) assessments before and after 8 × 30-s passive stretches without (PS+CON) or with VIB (PS+VIB) administered continuously throughout post-passive stretching tests. The passive properties of the muscle tendon unit were assessed pre- and post-passive stretching via PROM, passive torque (PASSTQ), and musculotendinous stiffness (MTS) measurements. PT, TTSINGLE, and TTDOUBLET decreased, whereas, %VI increased following passive stretching at PF and DF (P < 0.05) with no significant differences between PS+CON and PS+VIB. PASSTQ and MTS decreased while PROM increased post-passive stretching during both trials (P < 0.05). The stretching-induced force/torque deficit and increases in %VI were evident following passive stretching at short and long muscle lengths. Although not statistically significant, effect size calculations suggested large and moderate differences in the absolute changes in PT (Cohen's d = 1.14) and %VI (Cohen's d = 0.54) from pre- to post-passive stretching between treatments, with PS+VIB having greater decreases of PT and higher %VI than PS+CON. The decrement in PT following passive stretching may be primarily neural in origin.

Acute effect of passive static stretching on lower-body strength in moderately trained men.

PubMed

Gergley, Jeffrey C

2013-04-01

The purpose of this investigation was conducted to determine the acute effect of passive static stretching (PSS) of the lower-body musculature on lower-body strength in a 1 repetition maximum (1RM) squat exercise in young (18-24 years.) moderately trained men (n = 17). Two supervised warm-up treatments were applied before each performance testing session using a counterbalanced design on nonconsecutive days. The first treatment consisted of an active dynamic warm-up (AD) with resistance machines (i.e., leg extension/leg flexion) and free weights (i.e., barbell squat), whereas the second treatment added PSS of the lower body plus the AD treatment. One repetition maximum was determined using the maximum barbell squat following a progressive loading protocol. Subjects were also asked to subjectively evaluate their lower-body stability during 1RM testing sessions for both the AD and PSS treatments. A significant decrease in 1RM (8.36%) and lower-body stability (22.68%) was observed after the PSS treatment. Plausible explanations for this observation may be related to a more compliant muscle tendon unit and/or altered or impaired neurologic function in the active musculature. It is also possible that strength was impaired by the PSS because of joint instability. The findings of this study suggest that intensive stretching such as lower-body PSS should be avoided before training the lower body or performing the 1RM in the squat exercise in favor of an AD dynamic warm-up using resistance training equipment in the lower-body musculature.

Assessment of the stress transmitted to dental implants connected to screw-retained bars using different casting techniques.

PubMed

Haselhuhn, Klaus; Marotti, Juliana; Tortamano, Pedro; Weiss, Claudia; Suleiman, Lubna; Wolfart, Stefan

2014-12-01

Passive fit of the prosthetic superstructure is important to avoid complications; however, evaluation of passive fit is not possible using conventional procedures. Thus, the aim of this study was to check and locate mechanical stress in bar restorations fabricated using two casting techniques. Fifteen patients received four implants in the interforaminal region of the mandible, and a bar was fabricated using either the cast-on abutment or lost-wax casting technique. The fit accuracy was checked according to the Sheffield's test criteria. Measurements were recorded on the master model with a gap-free, passive fit using foil strain gauges both before and after tightening the prosthetic screws. Data acquisition and processing was analyzed with computer software and submitted to statistical analysis (ANOVA). The greatest axial distortion was at position 42 with the cast-on abutment technique, with a mean distortion of 450 μm/m. The lowest axial distortion occurred at position 44 with the lost-wax casting technique, with a mean distortion of 100 μm/m. The minimal differences between the means of axial distortion do not indicate any significant differences between the techniques (P = 0.2076). Analysis of the sensor axial distortion in relation to the implant position produced a significant difference (P < 0.0001). Significantly higher measurements were recorded in the axial distortion analysis of the distal sensors of implants at the 34 and 44 regions than on the mesial positions at the 32 and 42 regions (P = 0.0481). The measuring technique recorded axial distortion in the implant-supported superstructures. Distortions were present at both casting techniques, with no significant difference between the sides.

Changes in executive function after acute bouts of passive cycling in Parkinson's disease.

PubMed

Ridgel, Angela L; Kim, Chul-Ho; Fickes, Emily J; Muller, Matthew D; Alberts, Jay L

2011-04-01

Individuals with Parkinson's disease (PD) often experience cognitive declines. Although pharmacologic therapies are helpful in treating motor deficits in PD, they do not appear to be effective for cognitive complications. Acute bouts of moderate aerobic exercise have been shown to improve cognitive function in healthy adults. However, individuals with PD often have difficulty with exercise. This study examined the effects of passive leg cycling on executive function in PD. Executive function was assessed with Trail-Making Test (TMT) A and B before and after passive leg cycling. Significant improvements on the TMT-B test occurred after passive leg cycling. Furthermore, the difference between times to complete the TMT-B and TMT-A significantly decreased from precycling to postcycling. Improved executive function after passive cycling may be a result of increases in cerebral blood flow. These findings suggest that passive exercise could be a concurrent therapy for cognitive decline in PD.

Sesame indicum, a nutritional supplement, elicits antiamnesic effect via cholinergic pathway in scopolamine intoxicated mice.

PubMed

Chidambaram, Saravana Babu; Pandian, Anbarasi; Sekar, Sathiya; Haridass, Sumathy; Vijayan, Ranju; Thiyagarajan, Lakshmi Kantham; Ravindran, Jayasree; Balaji Raghavendran, Hanumantha Rao; Kamarul, Tunku

2016-12-01

Present study was undertaken to evaluate the antiamnesic effect of Sesamum indicum (S. indicum) seeds (standardized for sesamin, a lignan, content) in scopolamine, a muscarinic antagonist intoxicated mice. Male Swiss albino mice (18-22 g bw) were pretreated with methanolic extract of sesame seeds (MSSE) (100 and 200 mg/kg/day, p.o) for a period of 14 days. Scopolamine (0.3 mg/kg, i.p.) was injected on day 14, 45 ± 10 min after MSSE administration. Antiamnesic effect of MSSE was evaluated using step-down latency (SDL) on passive avoidance apparatus and transfer latency (TL) on an elevated plus maze. To unravel the mechanism of action, we examined the effects of MSSE on the genes such as acetyl cholinesterase (AChE), muscarinic receptor M1 subtype (mAChRM 1 ), and brain derived neurotrophic factor (BDNF) expression within hippocampus of experimental mice. Further, its effects on bax and bcl-2 were also evaluated. Histopathological examination of hippocampal CA 1 region was performed using cresyl violet staining. MSSE treatment produced a significant and dose dependent increase in step down latency in passive avoidance test and decrease in transfer latency in elevated plus maze in scopolamine intoxicated injected mice. MSSE down-regulated AChE and mAChRM 1 and up-regulated BDNF mRNA expression. Further, it significantly down-regulated the bax and caspase 3 and up-regulated bcl-2 expression in scopolamine intoxicated mice brains. Mice treated with MSSE showed increased neuronal counts in hippocampal CA 1 region when compared with scopolamine-vehicle treated mice. Sesame seeds have the ability to interact with cholinergic components involved in memory function/restoration and also an interesting candidate to be considered for future cognitive research. © 2015 Wiley Periodicals, Inc. Environ Toxicol 31: 1955-1963, 2016. © 2015 Wiley Periodicals, Inc.

Administration of nicotinic receptor antagonists during the period of memory consolidation affects passive avoidance learning and modulates synaptic efficiency in the CA1 region in vivo.

PubMed

Dobryakova, Y V; Gurskaya, O Ya; Markevich, V A

2015-01-22

We examined whether a non-selective antagonist of nAChRs mecamylamine and selective antagonists of α4β2-containing nAChRs dihydro-β-erythroidine (DHβE) and α7-containing nAChRs methyllycaconitine (MLA) affect learning performance and synaptic efficiency in the CA1 area of the hippocampus of freely moving rats during the memory consolidation period. Adult male Wistar rats received mecamylamine (0.5 mg/kg), DHβE (1 mg/kg), MLA (2 mg/kg) or saline immediately after training in a passive avoidance task. Memory retention was examined 24 h after the training. The changes in the latency of the first entry into a dark compartment of a test chamber were chosen as a criterion of learning. The ability of nAChRs antagonists to induce changes in the basal level of focal potentials (fEPSP, field excitatory postsynaptic potential) was estimated before training (baseline), 90 min after the training (consolidation period) and 24 h after the training (retention period). We found that in untrained rats mecamylamine, DHβE and MLA diminished the amplitude of fEPSP within the first 90 min after the injection; similar effect was observed in DHβE- and MLA-treated trained animals. These suppressive effects of DHβE and MLA were associated with memory loss. In contrast, mecamylamine, when applied to trained animals, tended to increase latency to enter the dark chamber and did not influence fEPSP during first 90 min after injection. Thus, the nAChRs antagonists with different selectivity induced different changes in fEPSP and behavior which suggests that nAChRs with different subunit composition are diversely involved in memory consolidation. Copyright © 2014 IBRO. Published by Elsevier Ltd. All rights reserved.

Behavioral deficits induced by third-trimester equivalent alcohol exposure in male C57BL/6J mice are not associated with reduced adult hippocampal neurogenesis but are still rescued with voluntary exercise.

PubMed

Hamilton, G F; Bucko, P J; Miller, D S; DeAngelis, R S; Krebs, C P; Rhodes, J S

2016-11-01

Prenatal alcohol exposure can produce permanent alterations in brain structure and profound behavioral deficits. Mouse models can help discover mechanisms and identify potentially useful interventions. This study examined long-term influences of either a single or repeated alcohol exposure during the third-trimester equivalent on survival of new neurons in the hippocampus, behavioral performance on the Passive avoidance and Rotarod tasks, and the potential role of exercise as a therapeutic intervention. C57BL/6J male mice received either saline or 5g/kg ethanol split into two s.c. injections, two hours apart, on postnatal day (PD)7 (Experiment 1) or on PD5, 7 and 9 (Experiment 2). All mice were weaned on PD21 and received either a running wheel or remained sedentary from PD35-PD80/81. From PD36-45, mice received i.p. injections of 50mg/kg bromodeoxyuridine (BrdU) to label dividing cells. Behavioral testing occurred between PD72-79. Number of surviving BrdU+ cells and immature neurons (doublecortin; DCX+) was measured at PD80-81. Alcohol did not affect number of BrdU+ or DCX+ cells in either experiment. Running significantly increased number of BrdU+ and DCX+ cells in both treatment groups. Alcohol-induced deficits on Rotarod performance and acquisition of the Passive avoidance task (Day 1) were evident only in Experiment 2 and running rescued these deficits. These data suggest neonatal alcohol exposure does not result in long-term impairments in adult hippocampal neurogenesis in the mouse model. Three doses of ethanol were necessary to induce behavioral deficits. Finally, the mechanisms by which exercise ameliorated the neonatal alcohol induced behavioral deficits remain unknown. Copyright © 2016 Elsevier B.V. All rights reserved.

Enhancement of Cognitive Functions by Aronia melanocarpa Elliot Through an Intermittent Ultrasonication Extraction Process.

PubMed

Kim, Nam Young; Lee, Hyeon Yong

2016-03-01

To increase the cognitive enhancement provided by Aronia melanocarpa Elliot (Aronia), Aronia was extracted using 70% ethanol solvent and six cycles of intermittent ultrasonication at 120 KHz for 50 min, followed by a rest for 10 min (UE), and was also extracted using 70% ethanol for 24 h at 80°C (EE) as a control process. In both in vivo water maze and passive avoidance tests, the UE showed better performance enhancement than the EE: in the water maze, mice treated with EE and UE showed escape latencies of 62.6 s and 54.3 s, respectively; for passive avoidance, they showed retention times of 45.9 s and 38.9 s, respectively. UE downregulated the expression level of acetylcholinesterase genes to 1.46 times compared with 1.72 for EE. However, there were no significant histological differences in the hippocampus between the mice fed with EE and those fed UE. Additionally, the UE was confirmed to have a greater antioxidant effect, 0.728 versus 0.561 for EE. Comparison of the high-performance liquid chromatography chromatograms of the extracts demonstrates that the intermittent ultrasonication process may improve the cognitive activities of Aronia by eluting higher amounts of cyanidin-3-galactoside (C3G). This work is the first to report that the crude extract from the intermittent ultrasonication process provided better cognitive enhancement than a single major bioactive substance, C3G itself, possibly through the synergistic effects of other anthocyanins present in the extract, such as delphine galactoside, cyanidin arabinoside, and cyanidin glucoside. We also believe that these findings may provide a reliable basis for developing natural plant drugs to compensate for the side effects of purified and/or chemically synthesized single-component drugs rather than to compete with them.

The effects of passive smoking on olfaction in children.

PubMed

Nageris, B; Hadar, T; Hansen, M C

2002-01-01

The effect of passive smoking on odor identification was studied in 10 children exposed to passive smoke at home. All had at least one parent who smoked at least one pack of cigarettes a day. The control group consisted of 10 children of nonsmoking parents. Ten odorants were tested: vinegar, ammonia, peppermint, roses, bleach, vanilla, cough drops, turpentine, licorice and mothballs. Each child was presented with five test trays containing all 10 odorants in random order. Of the total of 500 odors presented, the control group correctly identified 396 (79%) and the study group, 356 (71%) (p < 0.005). This work demonstrates that children exposed to passive smoke have difficulty identifying odors in comparison to children raised in relatively smoke-free environments. Since the study group tend to misidentify four of the 10 odorants tested--vanilla, roses, mothballs and cough drops--we suggest that these four odorants should suffice in testing odor identification in children.

General Aviation Interior Noise. Part 2; In-Flight Source/Verification

NASA Technical Reports Server (NTRS)

Unruh, James F.; Till, Paul D.; Palumbo, Daniel L. (Technical Monitor)

2002-01-01

The technical approach made use of the Cessna Model 182E aircraft used in the previous effort as a test bed for noise control application. The present phase of the project reports on flight test results during application of various passive noise treatments in an attempt to verify the noise sources and paths for the aircraft. The data presented establishes the level of interior noise control that can be expected for various passive noise control applications within the aircraft cabin. Subsequent testing will address specific testing to demonstrate the technology available to meet a specified level of noise control by application of passive and/or active noise control technology.

SPES-2, AP600 intergral system test S01007 2 inch CL to core make-up tank pressure balance line break

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bacchiani, M.; Medich, C.; Rigamonti, M.

1995-09-01

The SPES-2 is a full height, full pressure experimental test facility reproducing the Westinghouse AP600 reactor with a scaling factor of 1/395. The experimental plant, designed and operated by SIET in Piacenza, consists of a full simulation of the AP600 primary core cooling system including all the passive and active safety systems. In 1992, Westinghouse, in cooperation with ENEL (Ente Nazionale per l` Energia Elettrica), ENEA (Enter per le numove Technlogie, l` Energia e l` Ambient), Siet (Societa Informazioni Esperienze Termoidraulich) and ANSALDO developed an experimental program to test the integrated behaviour of the AP600 passive safety systems. The SPES-2more » test matrix, concluded in November 1994, has examined the AP600 passive safety system response for a range of small break LOCAs at different locations on the primary system and on the passive system lines; single steam generator tube ruptures with passive and active safety systems and a main steam line break transient to demonstrate the boration capability of passive safety systems for rapid cooldown. Each of the tests has provided detailed experimental results for verification of the capability of the analysis methods to predict the integrated passive safety system behaviour. Cold and hot shakedown tests have been performed on the facility to check the characteristics of the plant before starting the experimental campaign. The paper first presents a description of the SPES-2 test facility then the main results of S01007 test {open_quotes}2{close_quotes} Cold Leg (CL) to Core Make-up Tank (CMT) pressure balance line break{close_quotes} are reported and compared with predictions performed using RELAP5/mod3/80 obtained by ANSALDO through agreement with U.S.N.R.C. (U.S. Nuclear Regulatory Commission). The SPES-2 nodalization and all the calculations here presented were performed by ANSALDO and sponsored by ENEL as a part of pre-test predictions for SPES-2.« less

Testing the Feasibility of a Passive and Active Case Ascertainment System for Multiple Rare Conditions Simultaneously: The Experience in Three US States

PubMed Central

McDermott, Suzanne; Ruttenber, Margaret; Mann, Joshua; Smith, Michael G; Royer, Julie; Valdez, Rodolfo

2016-01-01

Background Owing to their low prevalence, single rare conditions are difficult to monitor through current state passive and active case ascertainment systems. However, such monitoring is important because, as a group, rare conditions have great impact on the health of affected individuals and the well-being of their caregivers. A viable approach could be to conduct passive and active case ascertainment of several rare conditions simultaneously. This is a report about the feasibility of such an approach. Objective To test the feasibility of a case ascertainment system with passive and active components aimed at monitoring 3 rare conditions simultaneously in 3 states of the United States (Colorado, Kansas, and South Carolina). The 3 conditions are spina bifida, muscular dystrophy, and fragile X syndrome. Methods Teams from each state evaluated the possibility of using current or modified versions of their local passive and active case ascertainment systems and datasets to monitor the 3 conditions. Together, these teams established the case definitions and selected the variables and the abstraction tools for the active case ascertainment approach. After testing the ability of their local passive and active case ascertainment system to capture all 3 conditions, the next steps were to report the number of cases detected actively and passively for each condition, to list the local barriers against the combined passive and active case ascertainment system, and to describe the experiences in trying to overcome these barriers. Results During the test period, the team from South Carolina was able to collect data on all 3 conditions simultaneously for all ages. The Colorado team was also able to collect data on all 3 conditions but, because of age restrictions in its passive and active case ascertainment system, it was able to report few cases of fragile X syndrome. The team from Kansas was able to collect data only on spina bifida. For all states, the implementation of an active component of the ascertainment system was problematic. The passive component appears viable with minor modifications. Conclusions Despite evident barriers, the joint passive and active case ascertainment of rare disorders using modified existing surveillance systems and datasets seems feasible, especially for systems that rely on passive case ascertainment. PMID:27574026

Prevalence, sociodemographic factors, psychological distress, and coping strategies related to compulsive buying: a cross sectional study in Galicia, Spain

PubMed Central

2014-01-01

Background Compulsive buying has become a serious problem affecting a growing number of people in contemporary consumer societies. Nevertheless, research examining its prevalence in representative samples from the general population is still scarce and mainly focused on the exploration of sociodemographic factors, neglecting other aspects like psychological distress and coping styles. Therefore, this study intends to contribute to the cumulative knowledge by assessing compulsive buying prevalence in a representative sample from the general population in the region of Galicia, in Spain. Sociodemographic determinants, psychological symptoms, and coping strategies are also analyzed to clarify their role in this phenomenon. Methods A random routes procedure was employed in the recruitment of the sample which was comprised of 2159 participants who were classified as either compulsive buyers or non-compulsive buyers. Both groups were compared regarding sociodemographic determinants, symptoms, and coping strategies through chi-square tests or analyses of variance. A multivariate logistic regression analysis was conducted to determine which of these determinants might play a part in the make up of a risk profile for compulsive buying. Results Estimated prevalence of compulsive buying was 7.1%. Compulsive buyers and non-compulsive buyers differed significantly in sex and age, with women and younger people showing a higher propensity for this phenomenon. Individuals with compulsive buying presented significantly higher scores on all the psychological symptoms considered. They also employed passive-avoidance coping strategies much more frequently and active strategies of problem solving and cognitive restructuring much less frequently. The logistic regression analysis results confirmed that being female, experiencing symptoms of anxiety, depression, and obsession-compulsion, and employing the passive-avoidance coping strategies of problem avoidance, wishful thinking, and self-criticism, all constituted risk factors for compulsive buying, whilst the increased age and the use of the active coping strategies of problem solving and cognitive restructuring were protection factors. Conclusions Our findings revealed a substantial prevalence of compulsive buying. Additionally, the relevance of sociodemographic determinants, psychological distress, and coping strategies in this problem was confirmed. The establishment of a risk profile for compulsive buying based on these different sets of determinants would likely contribute to the development of more effective intervention programs. PMID:24708814

Variable learning performance: the levels of behaviour organization.

PubMed

Csányi, V; Altbäcker, V

1990-01-01

Our experiments were focused on some special aspects of learning in the paradise fish. Passive avoidance conditioning method was used with different success depending on the complexity of the learning tasks. In the case of simple behavioural elements various "constrains" on avoidance learning were found. In a small, covered place the fish were ready to perform freezing reaction and mild punishment increased the frequency and duration of the freezing bouts very substantially. However, it was very difficult to enhance the frequency of freezing by punishment in a tank with transparent walls, where the main response to punishment was escape. The most easily learned tasks were the complex ones which had several different solutions. The fish learned to avoid either side of an aquarium very easily because they could use various behavioural elements to solve the problem. These findings could be interpreted within the framework of different organizational levels of behaviour.

[Focal cerebral ischemia in rats with estrogen deficiency and endothelial dysfunction].

PubMed

Litvinov, A A; Volotova, E V; Kurkin, D V; Logvinova, E O; Darmanyan, A P; Tyurenkov, I N

2017-01-01

To assess an effect of ovariectomy (OE) on the cerebral blood flow, endothelium-dependent vasodilation, neurological, cognitive and locomotor deficit as markers of brain damage after focal ischemia in rats. The study was conducted in 48 female Wistar rats. Ovariectomy was performed with ovaries and uterine body extirpation, cerebral ischemia was performed by middle cerebral artery occlusion (MCAO) in rats. To assess brain damage, Combs and Garcia scores, 'open field' test (OFT), 'extrapolatory escape test' (EET), 'passive avoidance test' (PAT), 'beam-walking test' were used. Cerebral blood flow was measured using ultrasonic flowmetry. After 7 days of MCAO, the cerebral blood flow in ovarioectomized animals was reduced by 20% compared to sham-ovariectomized animals. Ovariectomized animals with MCAO showed a three-fold endothelium-dependent vasodilation reduction (the reaction of cerebral vessels to the introduction of acetylcholine and N-L-arginine), indicating the presence of severe endothelial dysfunction. In ovarioectomized animals, the cerebral blood flow was reduced by 34% compared to sham-operated animals. MCAO and OE taken together resulted in more than 2-fold increase in neurological, motor disturbances, 3-fold decrease in motor activity of the animals in the OP test. Focal ischemia in ovarioectomized animals with endothelial dysfunction led to memory decrease by 1/5 fold in PAT and by 2-fold in EET.

An airborne sensor for the avoidance of clear air turbulence

NASA Technical Reports Server (NTRS)

Gary, B. L.

1981-01-01

This paper describes an airborne microwave radiometer that may be able to provide altitude guidance away from layers containing clear air turbulence, CAT. The sensor may also be able to predict upper limits for the severity of upcoming CAT. The 55 GHz radiometer is passive, not radar, and it measures the temperature of oxygen molecules in the viewing direction (averaged along a several-kilometer path). A small computer directs the viewing direction through elevation angle scans, and converts observed quantities to an 'altitude temperature profile'. The principle for CAT avoidance is that CAT is found statistically more often within inversion layers and at the tropopause, both of which are easily located from sensor-generated altitude temperature profiles.

Age differences in everyday problem-solving effectiveness: older adults select more effective strategies for interpersonal problems.

PubMed

Blanchard-Fields, Fredda; Mienaltowski, Andrew; Seay, Renee Baldi

2007-01-01

Using the Everyday Problem Solving Inventory of Cornelius and Caspi, we examined differences in problem-solving strategy endorsement and effectiveness in two domains of everyday functioning (instrumental or interpersonal, and a mixture of the two domains) and for four strategies (avoidance-denial, passive dependence, planful problem solving, and cognitive analysis). Consistent with past research, our research showed that older adults were more problem focused than young adults in their approach to solving instrumental problems, whereas older adults selected more avoidant-denial strategies than young adults when solving interpersonal problems. Overall, older adults were also more effective than young adults when solving everyday problems, in particular for interpersonal problems.

Original nootropic drug noopept prevents memory deficit in rats with muscarinic and nicotinic receptor blockade.

PubMed

Radionova, K S; Belnik, A P; Ostrovskaya, R U

2008-07-01

Antiamnesic activity of Noopept was studied on the original three-way model of conditioned passive avoidance response, which allows studying spatial component of memory. Cholinoceptor antagonists of both types (scopolamine and mecamylamine) decreased entry latency and reduced the probability for selection of the safe compartment. Noopept abolished the antiamnesic effect of cholinoceptor antagonists and improved spatial preference.

Euthanasia: a summary of the law in England and Wales.

PubMed

Simillis, Constantinos

2008-07-01

When medical treatment becomes futile, or the patient's suffering is intractable, doctors face the agonising dilemma of whether to proceed with euthanasia. It is important for a doctor to be familiar with the law surrounding euthanasia, in order to avoid prosecution. This paper explores the law in England and Wales regarding the different categories of euthanasia: voluntary euthanasia, nonvoluntary euthanasia, passive euthanasia, and active euthanasia.

Effects of Green Tea Extract on Learning, Memory, Behavior and Acetylcholinesterase Activity in Young and Old Male Rats

ERIC Educational Resources Information Center

Kaur, Tranum; Pathak, C. M.; Pandhi, P.; Khanduja, K. L.

2008-01-01

Objective: To study the effects of green tea extract administration on age-related cognition in young and old male Wistar rats. Methods: Young and old rats were orally administered 0.5% green tea extract for a period of eight weeks and were evaluated by passive avoidance, elevated maze plus paradigm and changes in acetylcholinesterase activity.…

Evaluation of passive avoidance learning and spatial memory in rats exposed to low levels of lead during specific periods of early brain development.

PubMed

Rao Barkur, Rajashekar; Bairy, Laxminarayana K

2015-01-01

Widespread use of heavy metal lead (Pb) for various commercial purposes has resulted in the environmental contamination caused by this metal. The studies have shown a definite relationship between low level lead exposure during early brain development and deficit in children's cognitive functions. This study investigated the passive avoidance learning and spatial learning in male rat pups exposed to lead through their mothers during specific periods of early brain development. Experimental male rats were divided into 5 groups: i) the normal control group (NC) (N = 12) consisted of rat offspring born to mothers who were given normal drinking water throughout gestation and lactation, ii) the pre-gestation lead exposed group (PG) (N = 12) consisted of rat offspring, mothers of these rats had been exposed to 0.2% lead acetate in the drinking water for 1 month before conception, iii) the gestation lead exposed group (G) (N = 12) contained rat offspring born to mothers who had been exposed to 0.2% lead acetate in the drinking water throughout gestation, iv) the lactation lead exposed group (L) (N = 12) had rat offspring, mothers of these rats exposed to 0.2% lead acetate in the drinking water throughout lactation and v) the gestation and lactation lead exposed group (GL) (N = 12) contained rat offspring, mothers of these rats were exposed to 0.2% lead acetate throughout gestation and lactation. The study found deficit in passive avoidance learning in the G, L and GL groups of rats. Impairment in spatial learning was found in the PG, G, L and GL groups of rats. Interestingly, the study found that gestation period only and lactation period only lead exposure was sufficient to cause deficit in learning and memory in rats. The extent of memory impairment in the L group of rats was comparable with the GL group of rats. So it can be said that postnatal period of brain development is more sensitive to neurotoxicity compared to prenatal exposure. This work is available in Open Access model and licensed under a CC BY-NC 3.0 PL license.

Prior fear conditioning does not impede enhanced active avoidance in serotonin transporter knockout rats.

PubMed

Schipper, Pieter; Henckens, Marloes J A G; Borghans, Bart; Hiemstra, Marlies; Kozicz, Tamas; Homberg, Judith R

2017-05-30

Stressors can be actively or passively coped with, and adequate adaption of the coping response to environmental conditions can reduce their potential deleterious effects. One major factor influencing stress coping behaviour is serotonin transporter (5-HTT) availability. Abolishment of 5-HTT is known to impair fear extinction but facilitates acquisition of signalled active avoidance (AA), a behavioural task in which an animal learns to avoid an aversive stimulus that is predicted by a cue. Flexibility in adapting coping behaviour to the nature of the stressor shapes resilience to stress-related disorders. Therefore, we investigated the relation between 5-HTT expression and ability to adapt a learned coping response to changing environmental conditions. To this end, we first established and consolidated a cue-conditioned passive fear response in 5-HTT -/- and wildtype rats. Next, we used the conditioned stimulus (CS) to signal oncoming shocks during signalled AA training in 5-HTT -/- and wildtype rats to study their capability to acquire an active coping response to the CS following fear conditioning. Finally, we investigated the behavioural response to the CS in a novel environment and measured freezing, exploration and self-grooming, behaviours reflective of stress coping strategy. We found that fear conditioned and sham conditioned 5-HTT -/- animals acquired the signalled AA response faster than wildtypes, while prior conditioning briefly delayed AA learning similarly in both genotypes. Subsequent exposure to the CS in the novel context reduced freezing and increased locomotion in 5-HTT -/- compared to wildtype rats. This indicates that improved AA performance in 5-HTT -/- rats resulted in a weaker residual passive fear response to the CS in a novel context. Fear conditioning prior to AA training did not affect freezing upon re-encountering the CS, although it did reduce locomotion in 5-HTT -/- rats. We conclude that independent of 5-HTT signalling, prior fear conditioning does not greatly impair the acquisition of subsequent active coping behaviour when the situation allows for it. Abolishment of 5-HTT results in a more active coping style in case of novelty-induced fear and upon CS encounter in a novel context after AA learning. Copyright © 2017 Elsevier B.V. All rights reserved.

Laboratory evaluation of two passive alcohol sensor devices

DOT National Transportation Integrated Search

1988-12-01

Passive alcohol sensing devices are designed to detect the presence of alcohol in a person's normally-expelled breath; they are "passive" in that one is not required to blow into a mouthpiece as with conventional breath test devices. The National Hig...

Active and realistic passive marijuana exposure tested by three immunoassays and GC/MS in urine

DOE Office of Scientific and Technical Information (OSTI.GOV)

Mule, S.J.; Lomax, P.; Gross, S.J.

Human urine samples obtained before and after active and passive exposure to marijuana were analyzed by immune kits (Roche, Amersham, and Syva) and gas chromatography/mass spectrometry (GC/MS). Seven of eight subjects were positive for the entire five-day test period with one immune kit. The latter correlated with GC/MS in 98% of the samples. Passive inhalation experiments under conditions likely to reflect realistic exposure resulted consistently in less than 10 ng/mL of cannabinoids. The 10-100-ng/mL cannabinoid concentration range essential for detection of occasional and moderate marijuana users is thus unaffected by realistic passive inhalation.

NCAM deficiency in the mouse forebrain impairs innate and learned avoidance behaviours.

PubMed

Brandewiede, J; Stork, O; Schachner, M

2014-06-01

The neural cell adhesion molecule (NCAM) has been implicated in the development and plasticity of neural circuits and the control of hippocampus- and amygdala-dependent learning and behaviour. Previous studies in constitutive NCAM null mutants identified emotional behaviour deficits related to disturbances of hippocampal and amygdala functions. Here, we studied these behaviours in mice conditionally deficient in NCAM in the postmigratory forebrain neurons. We report deficits in both innate and learned avoidance behaviours, as observed in elevated plus maze and passive avoidance tasks. In contrast, general locomotor activity, trait anxiety or neophobia were unaffected by the mutation. Altered avoidance behaviour of the conditional NCAM mutants was associated with a deficit in serotonergic signalling, as indicated by their reduced responsiveness to (±)-8-hydroxy-2-(dipropylamino)-tetralin-induced hypothermia. Another serotonin-dependent behaviour, namely intermale aggression that is massively increased in constitutively NCAM-deficient mice, was not affected in the forebrain-specific mutants. Our data suggest that genetically or environmentally induced changes of NCAM expression in the late postnatal and mature forebrain determine avoidance behaviour and serotonin (5-HT)1A receptor signalling. © 2014 John Wiley & Sons Ltd and International Behavioural and Neural Genetics Society.

The effects of different methods of emotional disclosure: differentiating post-traumatic growth from stress symptoms.

PubMed

Slavin-Spenny, Olga M; Cohen, Jay L; Oberleitner, Lindsay M; Lumley, Mark A

2011-10-01

Research on emotional disclosure should test the effects of different disclosure methods and whether symptoms are affected differently than post-traumatic growth. We randomized 214 participants with unresolved stressful experiences to four disclosure conditions (written, private spoken, talking to a passive listener, talking to an active facilitator) or two control conditions. All groups had one 30-minute session. After 6 weeks, disclosure groups reported more post-traumatic growth than controls, and disclosure conditions were similar in this effect. All groups decreased in stress symptoms (intrusions, avoidance, psychological and physical symptoms), but disclosure did not differ from control. We conclude that 30 minutes of disclosure leads to post-traumatic growth but not necessarily symptom reduction, and various disclosure methods have similar effects. Research on the effects of disclosure should focus on the benefits of growth as well as symptom reduction. © 2010 Wiley Periodicals, Inc.

Piperazines as nootropic agents: New derivatives of the potent cognition-enhancer DM235 carrying hydrophilic substituents.

PubMed

Martino, Maria Vittoria; Guandalini, Luca; Di Cesare Mannelli, Lorenzo; Menicatti, Marta; Bartolucci, Gianluca; Dei, Silvia; Manetti, Dina; Teodori, Elisabetta; Ghelardini, Carla; Romanelli, Maria Novella

2017-03-15

The piperazine ring of the potent nootropic drug DM235 has been decorated with H-bond donor and acceptor groups (CH 2 OH, CH 2 OMe, CH 2 OCOMe, COOEt); the aim was to insert new functional groups, suitable for further chemical manipulation. The influence of these modifications on nootropic activity was assessed by means of the mouse passive avoidance test; some of the newly synthesized molecules (alcohol 7b, acetate 8b and ester 10d) showed interesting in vivo potency. This makes it possible to use these functional groups for adding other residues, in order to increase molecular diversity, or for anchoring a biotin group, to obtain compounds useful to capture the biological target. Moreover, the new compounds will improve our knowledge of structure activity relationships of this family of drugs. Copyright © 2017 Elsevier Ltd. All rights reserved.

Disclosure of Research Results in Genetic Studies of Parkinson Disease Due to LRRK2 Mutations

PubMed Central

Bressman, Susan; Raymond, Deborah; Glickman, Amanda; Tolosa, Eduardo

2015-01-01

With the advent of large genetic studies examining both symptomatic and asymptomatic individuals, whether and how to disclose genetic research results have become pressing questions. The need is particularly acute in the case of LRRK2 research: Movement centers worldwide are recruiting cohorts of individuals with PD and their family members, including asymptomatic carriers, clinical features and treatment are complex and evolving, and disclosure policies vary at different sites and have been modified during the course of some studies. Herein, we present the major ethical principles of autonomy, beneficence, non-maleficence, and honesty that should guide disclosure policies in studies of families with LRRK2 mutations. We make recommendations regarding: genetic counseling, policies of either active or passive disclosure, responsibilities of funders to budget for genetic counseling, clinical genetic testing where locally required for disclosure, and aspects of study design to avoid mandatory disclosure whenever feasible. PMID:25952684

A trust region approach with multivariate Padé model for optimal circuit design

NASA Astrophysics Data System (ADS)

Abdel-Malek, Hany L.; Ebid, Shaimaa E. K.; Mohamed, Ahmed S. A.

2017-11-01

Since the optimization process requires a significant number of consecutive function evaluations, it is recommended to replace the function by an easily evaluated approximation model during the optimization process. The model suggested in this article is based on a multivariate Padé approximation. This model is constructed using data points of ?, where ? is the number of parameters. The model is updated over a sequence of trust regions. This model avoids the slow convergence of linear models of ? and has features of quadratic models that need interpolation data points of ?. The proposed approach is tested by applying it to several benchmark problems. Yield optimization using such a direct method is applied to some practical circuit examples. Minimax solution leads to a suitable initial point to carry out the yield optimization process. The yield is optimized by the proposed derivative-free method for active and passive filter examples.

The effect of red grape juice on Alzheimer's disease in rats

PubMed Central

Siahmard, Zahra; Alaei, Hojjatollah; Reisi, Parham; Pilehvarian, Ali Asghar

2012-01-01

Background: Alzheimer's disease is a neurodegenerative disease appearing as a result of free radicals and oxidative stress. Antioxidants agents boost memory and control Alzheimer's disease. Since red grape juice contains antioxidant agents, its effects on speed of learning and improvement of memory was studied in Alzheimer's rats. Materials and Methods: Alzheimer's model was induced by bilateral infusion of streptozocine into lateral ventricles of brain of male rats. Rats drank 10% red grape juice for 21 days. Passive avoidance learning test was used for measuring memory and learning in rats. Results: Our results showed that learning and memory in STZ-group decreased significantly compared to Sham group. However, intake of red grape juice increased speed of learning and improvement of memory in Alzheimer's rats. Conclusions: Our results suggest that there are active ingredients in red grape juice, which probably have therapeutic and preventive effects on cognitive impairments in Alzheimer's disease. PMID:23326794

The effect of red grape juice on Alzheimer's disease in rats.

PubMed

Siahmard, Zahra; Alaei, Hojjatollah; Reisi, Parham; Pilehvarian, Ali Asghar

2012-01-01

Alzheimer's disease is a neurodegenerative disease appearing as a result of free radicals and oxidative stress. Antioxidants agents boost memory and control Alzheimer's disease. Since red grape juice contains antioxidant agents, its effects on speed of learning and improvement of memory was studied in Alzheimer's rats. Alzheimer's model was induced by bilateral infusion of streptozocine into lateral ventricles of brain of male rats. Rats drank 10% red grape juice for 21 days. Passive avoidance learning test was used for measuring memory and learning in rats. Our results showed that learning and memory in STZ-group decreased significantly compared to Sham group. However, intake of red grape juice increased speed of learning and improvement of memory in Alzheimer's rats. Our results suggest that there are active ingredients in red grape juice, which probably have therapeutic and preventive effects on cognitive impairments in Alzheimer's disease.

Behavioral Characterization of a Mouse Model Overexpressing DSCR1/ RCAN1

PubMed Central

Dierssen, Mara; Arqué, Gloria; McDonald, Jerome; Andreu, Nuria; Martínez-Cué, Carmen; Flórez, Jesús; Fillat, Cristina

2011-01-01

DSCR1/ RCAN1 is a chromosome 21 gene found to be overexpressed in the brains of Down syndrome (DS) and postulated as a good candidate to contribute to mental disability. However, even though Rcan1 knockout mice have pronounced spatial learning and memory deficits, the possible deleterious effects of its overexpression in DS are not well understood. We have generated a transgenic mouse model overexpressing DSCR1/RCAN1 in the brain and analyzed the effect of RCAN1 overexpression on cognitive function. TgRCAN1 mice present a marked disruption of the learning process in a visuo-spatial learning task. However, no significant differences were observed in the performance of the memory phase of the test (removal session) nor in a step-down passive avoidance task, thus suggesting that once learning has been established, the animals are able to consolidate the information in the longer term. PMID:21364922

Act Your (Old) Age: Prescriptive, Ageist Biases Over Succession, Consumption, and Identity

PubMed Central

North, Michael S.; Fiske, Susan T.

2015-01-01

Perspectives on ageism have focused on descriptive stereotypes concerning what older people allegedly are. By contrast, we introduce prescriptive stereotypes that attempt to control how older people should be: encouraging active Succession of envied resources, preventing passive Consumption of shared resources, and avoidance of symbolic, ingroup identity resources. Six studies test these domains, utilizing vignette experiments and simulated behavioral interactions. Across studies, younger (compared with middle-aged and older) raters most resented elder violators of prescriptive stereotypes. Moreover, these younger participants were most polarized toward older targets (compared with middle-aged and younger analogues) – rewarding elders most for prescription adherences and punishing them most for violations. Taken together, these findings offer a novel approach to ageist prescriptions, which disproportionately target older people, are most endorsed by younger people, and suggest how elders shift from receiving the default prejudice of pity to either prescriptive resentment or reward. PMID:23471317

Environmental change during postnatal development alters behaviour, cognitions and neurogenesis of mice.

PubMed

Iso, Hiroyuki; Simoda, Shigero; Matsuyama, Tomohiro

2007-04-16

Four groups of male C57BL/6 mice were reared differing combinations of the two environments from 3 to 11 weeks after birth. At 12 and 13 weeks they were assessed by measures of behaviour and learning: open-field activity, auditory startle reflex and prepulse inhibition, water maze learning, and passive avoidance. Another four groups of mice reared under these varying conditions were examined for generation of neurons in hippocampus and cerebral cortex using bromodeoxyuridine (BrdU) at 12 weeks. Enriched (EE) and impoverished (PP) groups were housed in their respective environment for 8 weeks, enriched-impoverished (EP) and impoverished-enriched (PE) mice respectively were reared for 6 weeks in the first-mentioned environment and then for 2 weeks in the second. PP and EP mice showed hyperactivity, greater startle amplitude and significantly slower learning in a water maze than EE or PE animals, and also showed a memory deficit in a probe test, avoidance performance did not differ. Neural generation was greater in the EE and PE than PP and EP groups, especially in the hippocampus. These results suggest that environmental change critically affects behavioural and anatomic brain development, even if brief. In these mice, the effect of unfavourable early experience could be reversed by a later short of favourable experience.

Additive effect of harmane and muscimol for memory consolidation impairment in inhibitory avoidance task.

PubMed

Nasehi, Mohammad; Morteza-Zadeh, Parastoo; Khakpai, Fatemeh; Zarrindast, Mohammad-Reza

2016-12-17

In the current study, we examined the effect of bilateral intra-dorsal hippocampal (intra-CA1) microinjections of GABA A receptor agents on amnesia induced by a β-carboline alkaloid, harmane in mice. We used a single-trial step-down passive avoidance task to assess memory retention and then, open-field test to assess locomotor activity. The results indicated that post-training intra-CA1 injections of bicuculline - a GABA A receptor antagonist - had no significant effect, while muscimol (0.01 and 0.1μg/mouse) - a GABA A receptor agonist - impaired memory consolidation. Post-training intra-peritoneal (i.p.) infusion of harmane (3 and 5mg/kg) decreased memory consolidation. Furthermore, post-training intra-CA1 administration of sub-threshold dose of bicuculline (0.001μg/mouse) restored, whereas muscimol (0.001μg/mouse) potentiated impairment of memory consolidation induced by harmane. The isobologram analysis revealed that there is an additive effect between harmane and muscimol on impairment of memory consolidation. Moreover, all above doses of drugs did not alter locomotor activity. These findings suggest that GABA A receptors of the CA1 area, at least partly, play a role in modulating the effect of harmane on memory consolidation. Copyright © 2016 IBRO. Published by Elsevier Ltd. All rights reserved.

Passive stiffness of rat skeletal muscle undernourished during fetal development

PubMed Central

Toscano, Ana Elisa; Ferraz, Karla Mônica; de Castro, Raul Manhães; Canon, Francis

2010-01-01

OBJECTIVES: The aim of the study was to investigate the effect of fetal undernutrition on the passive mechanical properties of skeletal muscle of weaned and young adult rats. INTRODUCTION: A poor nutrition supply during fetal development affects physiological functions of the fetus. From a mechanical point of view, skeletal muscle can be also characterized by its resistance to passive stretch. METHODS: Male Wistar rats were divided into two groups according to their mother's diet during pregnancy: a control group (mothers fed a 17% protein diet) and an isocaloric low‐protein group (mothers fed a 7.8% protein diet). At birth, all mothers received a standardized meal ad libitum. At the age of 25 and 90 days, the soleus muscle and extensor digitorum longus (EDL) muscles were removed in order to test the passive mechanical properties. A first mechanical test consisted of an incremental stepwise extension test using fast velocity stretching (500 mm/s) enabling us to measure, for each extension stepwise, the dynamic stress (σd) and the steady stress (σs). A second test consisted of a slow velocity stretch in order to calculate normalized stiffness and tangent modulus from the stress–strain relationship. RESULTS: The results for the mechanical properties showed an important increase in passive stiffness in both the soleus and EDL muscles in weaned rat. In contrast, no modification was observed in young adult rats. CONCLUSIONS: The increase in passive stiffness in skeletal muscle of weaned rat submitted to intrauterine undernutrition it is most likely due to changes in muscle passive stiffness. PMID:21340228

Egis-11150: a candidate antipsychotic compound with procognitive efficacy in rodents.

PubMed

Gacsályi, István; Nagy, Katalin; Pallagi, Katalin; Lévay, György; Hársing, László G; Móricz, Krisztina; Kertész, Szabolcs; Varga, Péter; Haller, József; Gigler, Gábor; Szénási, Gábor; Barkóczy, József; Bíró, Judit; Spedding, Michael; Antoni, Ferenc A

2013-01-01

Classical antipsychotics, e.g. haloperidol, chlorpromazine, are potent at controlling the positive symptoms of schizophrenia but frequently elicit extrapyramidal motor side-effects. The introduction of atypical antipsychotics such as risperidone, olanzapine and clozapine has obviated this problem, but none of the current drugs seem to improve the cognitive deficits accompanying schizophrenia. Thus there is an unmet need for agents that not only suppress the psychotic symptoms but also ameliorate the impairment of cognition. Here, we report the preclinical properties of a candidate antipsychotic, Egis-11150, that shows marked pro-cognitive efficacy. Egis-11150 displayed high affinity for adrenergic α(1), α(2c), 5-HT(2A) 5-HT₇, moderate affinity for adrenergic α(2a) and D₂ receptors. It was a functional antagonist on all of the above receptors, with the exception of 5-HT₇ receptors, where it was an inverse agonist. Phencyclidine-induced hypermotility in mice and inhibition of conditioned avoidance response in rats were assessed to estimate efficacy against the positive and social withdrawal test in rats was used to predict efficacy against the negative symptoms of schizophrenia. Passive-avoidance learning, novel object recognition and radial maze tests in rats were used to assess pro-cognitive activity, while phencyclidine-induced disruption of prepulse inhibition in mice was examined to test for effects on attention. Egis-11150 (0.01-0.3 mg/kg, ip.) was effective in all of the preclinical models of schizophrenia examined. Moreover, a robust pro-cognitive profile was apparent. In summary, work in preclinical models indicates that Egis-11150 is a potential treatment for controlling the psychosis as well as the cognitive dysfunction in schizophrenia. This article is part of a Special Issue entitled 'Cognitive Enhancers'. Copyright © 2012 Elsevier Ltd. All rights reserved.

Analysis of maxillary arch force/couple systems for a simulated high canine malocclusion: Part 2. Elastic ligation.

PubMed

Fok, Jonathan; Toogood, Roger W; Badawi, Hisham; Carey, Jason P; Major, Paul W

2011-11-01

To better understand the mechanics of bracket/archwire interaction through analysis of force and couple distribution along the maxillary arch using elastic ligation and to compare these results with passive ligation. An orthodontic simulator was used to study a high canine malocclusion. Force and couple distributions produced by elastic ligation and round wire were measured. Forces and couples were referenced to the center of resistance of each tooth. Tests were repeated for 12 bracket sets with 12 wires per set. Data were compared with those derived from similar tests for passive ligation. Propagation of the force/couple systems around the arch using elastic ligation was extensive. Elastic ligation produced significantly more resistance to sliding, contributing to higher forces and couples at the center of resistance than were observed for passive ligation. The results of this study suggest some potential mechanical advantages of passive over elastic ligation. In particular, limited propagation around the arch in passive ligation reduces the occurrence of unwanted force/couple systems compared with elastic ligation. These advantages may not transfer to a clinical setting because of the conditions of the tests; additional testing would be required to determine whether these advantages can be generalized.

Adaptation to nonlinear frequency compression in normal-hearing adults: a comparison of training approaches.

PubMed

Dickinson, Ann-Marie; Baker, Richard; Siciliano, Catherine; Munro, Kevin J

2014-10-01

To identify which training approach, if any, is most effective for improving perception of frequency-compressed speech. A between-subject design using repeated measures. Forty young adults with normal hearing were randomly allocated to one of four groups: a training group (sentence or consonant) or a control group (passive exposure or test-only). Test and training material differed in terms of material and speaker. On average, sentence training and passive exposure led to significantly improved sentence recognition (11.0% and 11.7%, respectively) compared with the consonant training group (2.5%) and test-only group (0.4%), whilst, consonant training led to significantly improved consonant recognition (8.8%) compared with the sentence training group (1.9%), passive exposure group (2.8%), and test-only group (0.8%). Sentence training led to improved sentence recognition, whilst consonant training led to improved consonant recognition. This suggests learning transferred between speakers and material but not stimuli. Passive exposure to sentence material led to an improvement in sentence recognition that was equivalent to gains from active training. This suggests that it may be possible to adapt passively to frequency-compressed speech.

Whole body vibration improves cognition in healthy young adults.

PubMed

Regterschot, G Ruben H; Van Heuvelen, Marieke J G; Zeinstra, Edzard B; Fuermaier, Anselm B M; Tucha, Lara; Koerts, Janneke; Tucha, Oliver; Van Der Zee, Eddy A

2014-01-01

This study investigated the acute effects of passive whole body vibration (WBV) on executive functions in healthy young adults. Participants (112 females, 21 males; age: 20.5±2.2 years) underwent six passive WBV sessions (frequency 30 Hz, amplitude approximately 0.5 mm) and six non-vibration control sessions of two minutes each while sitting on a chair mounted on a vibrating platform. A passive WBV session was alternated with a control session. Directly after each session, performance on the Stroop Color-Block Test (CBT), Stroop Color-Word Interference Test (CWIT), Stroop Difference Score (SDS) and Digit Span Backward task (DSBT) was measured. In half of the passive WBV and control sessions the test order was CBT-CWIT-DSBT, and DSBT-CBT-CWIT in the other half. Passive WBV improved CWIT (p = 0.009; effect size r = 0.20) and SDS (p = 0.034; r = 0.16) performance, but only when the CBT and CWIT preceded the DSBT. CBT and DSBT performance did not change. This study shows that two minutes passive WBV has positive acute effects on attention and inhibition in young adults, notwithstanding their high cognitive functioning which could have hampered improvement. This finding indicates the potential of passive WBV as a cognition-enhancing therapy worth further evaluation, especially in persons unable to perform active forms of exercise.

Passive smoking increased risk of gestational diabetes mellitus independently and synergistically with prepregnancy obesity in Tianjin, China.

PubMed

Leng, Junhong; Wang, Peng; Shao, Ping; Zhang, Cuiping; Li, Weiqin; Li, Nan; Wang, Leishen; Nan, Hairong; Yu, Zhijie; Hu, Gang; Chan, Juliana C N; Yang, Xilin

2017-03-01

Passive smoking increased type 2 diabetes mellitus risk, but it is uncertain whether it also increased gestational diabetes mellitus (GDM) risk. We aimed to examine the association of passive smoking during pregnancy and its interaction with maternal obesity for GDM. From 2010 to 2012, 12 786 Chinese women underwent a 50-g 1-hour glucose challenge test at 24 to 28 weeks of gestation and further underwent a 75-g 2-hour oral glucose tolerance test if the glucose challenge test result was ≥7.8 mmol/L. GDM was defined by the International Association of Diabetes and Pregnancy Study Group's cut points. Self-reported passive smoking during pregnancy was collected by a questionnaire. Logistic regression was used to obtain odds ratios (ORs) and 95% confidence intervals (CIs). Additive interaction between maternal obesity and passive smoking was estimated using relative excess risk due to interaction (RERI), attributable proportion due to interaction (AP), and synergy index (S). Significant RERI > 0, AP > 0, or S > 1 indicated additive interaction. A total of 8331 women (65.2%) were exposed to passive smoking during pregnancy. More women exposed to passive smoking developed GDM than nonexposed women (7.8% versus 6.3%, P = 0.002) with an adjusted OR of 1.29 (95%CI, 1.11 to 1.50). Compared with nonobesity and nonpassive smoking, prepregnancy obesity and passive smoking was associated with GDM risk with an adjusted OR of 3.09 (95%CI, 2.38-4.02) with significant additive interaction (P < .05 for RERI and AP). Passive smoking during pregnancy increased GDM risk in Chinese women independently and synergistically with prepregnancy obesity. Copyright © 2016 John Wiley & Sons, Ltd.

Active Oxidation of a UHTC-Based CMC

NASA Technical Reports Server (NTRS)

Glass, David E.; Splinter, Scott C.

2012-01-01

The active oxidation of ceramic matrix composites (CMC) is a severe problem that must be avoided for multi-use hypersonic vehicles. Much work has been performed studying the active oxidation of silicon-based CMCs such as C/SiC and SiC-coated carbon/carbon (C/C). Ultra high temperature ceramics (UTHC) have been proposed as a possible material solution for high-temperature applications on hypersonic vehicles. However, little work has been performed studying the active oxidation of UHTCs. The intent of this paper is to present test data indicating an active oxidation process for a UHTC-based CMC similar to the active oxidation observed with Si-based CMCs. A UHTC-based CMC was tested in the HyMETS arc-jet facility (or plasma wind tunnel, PWT) at NASA Langley Research Center, Hampton, VA. The coupon was tested at a nominal surface temperature of 3000 F (1650 C), with a stagnation pressure of 0.026 atm. A sudden and large increase in surface temperature was noticed with negligible increase in the heat flux, indicative of the onset of active oxidation. It is shown that the surface conditions, both temperature and pressure, fall within the region for a passive to active transition (PAT) of the oxidation.

The chalcone derivative Chana 1 protects against amyloid β peptide-induced oxidative stress and cognitive impairment.

PubMed

Kwak, Jieun; Kim, Mi-Jeong; Choi, Kyung-Chul; Choi, Hyo-Kyung; Jun, Woojin; Park, Hyun-Jin; Lee, Yoo-Hyun; Yoon, Ho-Geun

2012-07-01

Alzheimer's disease (AD) is the most common neurodegenerative disease to cause dementia in the elderly. Amyloid β (Aβ)-peptide induced oxidative stress causes the initiation and progression of AD. Recently, new chalcone derivatives termed the Chana series were synthesized. Among them, Chana 1 showed high free radical scavenging activity (72.5%), as measured by a DPPH (1,1-diphenyl-2-picrylhydrazyl) assay. In this study, we investigated the effect of Chana 1 against Aβ-induced cytotoxicity and cognitive deficits. Additionally, we sought to estimate the lethal dose, 50% (LD50) of Chana 1 in mice using an acute oral toxicity test. We found that Chana 1 significantly protected against Aβ-induced neuronal cell death in PC12 cells. Oral administration of Chana 1 at a dose of 50 mg/kg body weight/day significantly improved Aβ-induced learning and memory impairment in mice, as measured in Y-maze and passive avoidance tests. In acute toxicity tests, the LD50 in mice was determined to be 520.44 mg/kg body weight. The data are valuable for future studies and suggest that Chana 1 has therapeutic potential for the management of neurodegenerative disease.

Predicting personality disorder functioning styles by the Chinese Adjective Descriptors of Personality: a preliminary trial in healthy people and personality disorder patients.

PubMed

Fan, Hongying; Zhu, Qisha; Ma, Guorong; Shen, Chanchan; Zhang, Bingren; Wang, Wei

2016-08-30

Cultural and personality factors might contribute to the clinical differences of psychiatric patients all over the world including China. One cultural oriented Chinese Adjective Descriptors of Personality (CADP) designed to measure normal personality traits, might be specifically associated with different personality disorder functioning styles. We therefore have invited 201 healthy volunteers and 67 personality disorder patients to undergo CADP, the Parker Personality Measure (PERM), and the Plutchik-van Praag Depression Inventory (PVP) tests. Patients scored significantly higher on PVP scale and all 11 PERM personality disorder functioning styles, as well as CADP Emotional and Unsocial traits. The PVP was significantly correlated with some CADP traits and PERM styles in both groups. In healthy volunteers, only one CADP trait, Unsocial, prominently predicted 11 PERM styles. By contrast in patients, CADP Intelligent predicted the PERM Narcissistic and Passive-Aggressive styles; CADP Emotional the PERM Paranoid, Borderline, and Histrionic styles; CADP Conscientious the PERM Obsessive-Compulsive style; CADP Unsocial the PERM Schizotypal, Antisocial, Narcissistic, Avoidant, Dependent, and Passive-Aggressive styles; CADP Agreeable the PERM Antisocial style. As a preliminary study, our results demonstrated that, in personality disorder patients, all five CADP traits were specifically associated with almost all 11 personality disorder functioning styles, indicating that CADP might be used as an aid to diagnose personality disorders in China.

Clozapine and Olanzapine Exhibit an Intrinsic Anxiolytic Property in Two Conditioned Fear Paradigms: Contrast with Haloperidol and Chlordiazepoxide

PubMed Central

Mead, Alexa; Li, Ming; Kapur, Shitij

2008-01-01

Psychotic fear and anxiety disturbances are seen at a relatively high frequency in patients with schizophrenia. Atypical antipsychotics are believed to show superior efficacy in reducing these symptoms. However, clinical and preclinical evidence regarding their anxiolytic efficacy has been mixed. In this study, we evaluated the possible anxiolytic property of two atypicals clozapine and olanzapine and compared them with typical haloperidol and chlordiazepoxide (a prototype of sedative-anxiolytic drug) in two preclinical models of fear. In Experiment 1, we used a fear-induced passive avoidance and conditioned place aversion paradigm and examined the effects of clozapine (20 mg/kg, sc), haloperidol (0.05 mg/kg, sc) and chlordiazepoxide (10 mg/kg, ip). In Experiments 2 and 3, we used a two-way active avoidance conditioning paradigm and further compared the effects of clozapine (20 mg/kg, sc), haloperidol (0.05 mg/kg, sc), chlordiazepoxide (10 mg/kg, ip) and three doses of olanzapine (0.5, 1.0, and 2.0 mg/kg, sc). Results show that clozapine and chlordiazepoxide, but not haloperidol, significantly attenuated the shock conditioning-induced place aversion, decreased the amount of defecations and the number of the 22 kHz vocalizations. Clozapine also reduced the shock conditioning-induced hyperthermia. Similar to clozapine, olanzapine also significantly decreased the amount of defecations and reduced the shock conditioning-induced hyperthermia, but it did not inhibit the 22 kHz vocalizations. This study demonstrates that clozapine and olanzapine possess an intrinsic anxiolytic property, which is not attributable to its superior anti-“psychotic” effect or its favorable effects on motor functions or learning and memory processes. These findings also suggest that the combined use of passive avoidance and active avoidance conditioning models can be useful in better differentiating typical and atypical antipsychotics as well as anxiolytics. PMID:18547622

Passive band-gap reconfiguration born from bifurcation asymmetry.

PubMed

Bernard, Brian P; Mann, Brian P

2013-11-01

Current periodic structures are constrained to have fixed energy transmission behavior unless active control or component replacement is used to alter their wave propagation characteristics. The introduction of nonlinearity to generate multiple stable equilibria is an alternative strategy for realizing distinct energy propagation behaviors. We investigate the creation of a reconfigurable band-gap system by implementing passive switching between multiple stable states of equilibrium, to alter the level of energy attenuation in response to environmental stimuli. The ability to avoid potentially catastrophic loads is demonstrated by tailoring the bandpass and band-gap regions to coalesce for two stable equilibria and varying an external load parameter to trigger a bifurcation. The proposed phenomenon could be utilized in remote or autonomous applications where component modifications and active control are impractical.

Emerging Needs for Pervasive Passive Wireless Sensor Networks on Aerospace Vehicles

NASA Technical Reports Server (NTRS)

Wilson, William C.; Juarez, Peter D.

2014-01-01

NASA is investigating passive wireless sensor technology to reduce instrumentation mass and volume in ground testing, air flight, and space exploration applications. Vehicle health monitoring systems (VHMS) are desired on all aerospace programs to ensure the safety of the crew and the vehicles. Pervasive passive wireless sensor networks facilitate VHMS on aerospace vehicles. Future wireless sensor networks on board aerospace vehicles will be heterogeneous and will require active and passive network systems. Since much has been published on active wireless sensor networks, this work will focus on the need for passive wireless sensor networks on aerospace vehicles. Several passive wireless technologies such as microelectromechanical systems MEMS, SAW, backscatter, and chipless RFID techniques, have all shown potential to meet the pervasive sensing needs for aerospace VHMS applications. A SAW VHMS application will be presented. In addition, application areas including ground testing, hypersonic aircraft and spacecraft will be explored along with some of the harsh environments found in aerospace applications.

Inbreeding and inbreeding avoidance in wild giant pandas.

PubMed

Hu, Yibo; Nie, Yonggang; Wei, Wei; Ma, Tianxiao; Van Horn, Russell; Zheng, Xiaoguang; Swaisgood, Ronald R; Zhou, Zhixin; Zhou, Wenliang; Yan, Li; Zhang, Zejun; Wei, Fuwen

2017-10-01

Inbreeding can have negative consequences on population and individual fitness, which could be counteracted by inbreeding avoidance mechanisms. However, the inbreeding risk and inbreeding avoidance mechanisms in endangered species are less studied. The giant panda, a solitary and threatened species, lives in many small populations and suffers from habitat fragmentation, which may aggravate the risk of inbreeding. Here, we performed long-term observations of reproductive behaviour, sampling of mother-cub pairs and large-scale genetic analyses on wild giant pandas. Moderate levels of inbreeding were found in 21.1% of mating pairs, 9.1% of parent pairs and 7.7% of panda cubs, but no high-level inbreeding occurred. More significant levels of inbreeding may be avoided passively by female-biased natal dispersal rather than by breeding dispersal or active relatedness-based mate choice mechanisms. The level of inbreeding in giant pandas is greater than expected for a solitary mammal and thus warrants concern for potential inbreeding depression, particularly in small populations isolated by continuing habitat fragmentation, which will reduce female dispersal and increase the risk of inbreeding. © 2017 John Wiley & Sons Ltd.

Taurine induces anti-anxiety by activating strychnine-sensitive glycine receptor in vivo.

PubMed

Zhang, Cheng Gao; Kim, Sung-Jin

2007-01-01

Taurine has a variety of actions in the body such as cardiotonic, host-defensive, radioprotective and glucose-regulatory effects. However, its action in the central nervous system remains to be characterized. In the present study, we tested to see whether taurine exerts anti-anxiety effects and to explore its mechanism of anti-anxiety activity in vivo. The staircase test and elevated plus maze test were performed to test the anti-anxiety action of taurine. Convulsions induced by strychnine, picrotoxin, yohimbine and isoniazid were tested to explore the mechanism of anti-anxiety activity of taurine. The Rotarod test was performed to test muscle relaxant activity and the passive avoidance test was carried out to test memory activity in response to taurine. Taurine (200 mg/kg, p.o.) significantly reduced rearing numbers in the staircase test while it increased the time spent in the open arms as well as the number of entries to the open arms in the elevated plus maze test, suggesting that it has a significant anti-anxiety activity. Taurine's action could be due to its binding to and activating of strychnine-sensitive glycine receptor in vivo as it inhibited convulsion caused by strychnine; however, it has little effect on picrotoxin-induced convulsion, suggesting its anti-anxiety activity may not be linked to GABA receptor. It did not alter memory function and muscle activity. Taken together, these results suggest that taurine could be beneficial for the control of anxiety in the clinical situations. Copyright (c) 2007 S. Karger AG, Basel.

Corrosion behavior of ODS steels with several chromium contents in hot nitric acid solutions

NASA Astrophysics Data System (ADS)

Tanno, Takashi; Takeuchi, Masayuki; Ohtsuka, Satoshi; Kaito, Takeji

2017-10-01

Oxide dispersion strengthened (ODS) steel cladding tubes have been developed for fast reactors. Tempered martensitic ODS steels with 9 and 11 wt% of chromium (9Cr-, 11Cr-ODS steel) are the candidate material in research being carried out at JAEA. In this work, fundamental immersion tests and electrochemical tests of 9 to 12Cr-ODS steels were systematically conducted in various nitric acid solutions at 95 °C. The corrosion rate decreased exponentially with effective solute chromium concentration (Creff) and nitric acid concentration. Addition of vanadium (V) and ruthenium (Ru) also decreased the corrosion rate. The combination of low Creff and dilute nitric acid could not avoid the active mass dissolution during active domain at the beginning of immersion, and the corrosion rate was high. Higher Creff decreased the partial anodic current during the active domain and assisted the passivation of the surface of the steel. Concentrated nitric acid and addition of Ru and V increased partial cathodic current and shifted the corrosion potential to noble side. These effects should have prevented the active mass dissolution and decreased the corrosion rate.

Feeding Vitamin C during Neonatal and Juvenile Growth Improves Learning and Memory of Rats.

PubMed

Hosseini, Mahmoud; Beheshti, Farimah; Sohrabi, Farzaneh; Vafaee, Farzaneh; Shafei, Mohammad Naser; Reza Sadeghnia, Hamid

2018-09-03

We investigated the effects of feeding vitamin C (Vit C) during neonatal and juvenile growth on learning and memory of rats. Rats after delivery were randomly divided into four groups and treated. Group 1, control group, received normal drinking water. Groups 2-4 received Vit C 10, 100, and 500 mg/kg, respectively, from the first day. After 8 weeks, 10 male offspring of each group were randomly selected and tested in the Morris water maze (MWM) and passive avoidance (PA) tests. Finally, the brains were removed for biochemical measurement. In MWM, 10-500 mg/kg Vit C reduced the latency and traveled distance and increased time spent in the target quadrant. In PA, 10 and 100 mg/kg of Vit C increased the latency; 10-500 mg/kg of Vit C decreased the malondialdehyde (MDA) in the brain tissues and increased thiol and catalase (CAT) activity compared to the control group. We showed that feeding rats Vit C during neonatal and juvenile growth has positive effects on learning and memory.

NASA and ESA Collaboration on Alternative to Nitric Acid Passivation: Parameter Optimization of Citric Acid Passivation for Stainless Steel Alloys

NASA Technical Reports Server (NTRS)

Kessel, Kurt R.

2016-01-01

National Aeronautics and Space Administration (NASA) Headquarters chartered the Technology Evaluation for Environmental Risk Mitigation Principal Center (TEERM) to coordinate agency activities affecting pollution prevention issues identified during system and component acquisition and sustainment processes. The primary objectives of NASA TEERM are to: Reduce or eliminate the use of hazardous materials or hazardous processes at manufacturing, remanufacturing, and sustainment locations. Avoid duplication of effort in actions required to reduce or eliminate hazardous materials through joint center cooperation and technology sharing. Corrosion is an extensive problem that affects the National Aeronautics and Space Administration (NASA) and the European Space Agency (ESA). The damaging effects of corrosion result in steep costs, asset downtime affecting mission readiness, and safety risks to personnel. Consequently, it is vital to reduce corrosion costs and risks in a sustainable manner. NASA and ESA have numerous structures and equipment that are fabricated from stainless steel. The standard practice for protection of stainless steel is a process called passivation. Passivation is defined by The American Heritage Dictionary of the English Language as to treat or coat (a metal) in order to reduce the chemical reactivity of its surface. Passivation works by forming a shielding outer (metal oxide) layer that reduces the impact of destructive environmental factors such as air or water. Consequently, this process necessitates a final product that is very clean and free of iron and other contaminants. Typical passivation procedures call for the use of nitric acid; however, there are a number of environmental, worker safety, and operational issues associated with its use. Citric acid is an alternative to nitric acid for the passivation of stainless steels. Citric acid offers a variety of benefits including increased safety for personnel, reduced environmental impact, and reduced operational cost. The primary objective of this effort is to qualify citric acid as an environmentally-preferable alternative to nitric acid for the passivation of stainless steel alloys. While citric acid use has become more prominent in industry, there is little evidence that citric acid is a technically sound passivation agent, especially for the unique and critical applications encountered by NASA and ESA.

Effective Surface Passivation of InP Nanowires by Atomic-Layer-Deposited Al2O3 with POx Interlayer.

PubMed

Black, L E; Cavalli, A; Verheijen, M A; Haverkort, J E M; Bakkers, E P A M; Kessels, W M M

2017-10-11

III/V semiconductor nanostructures have significant potential in device applications, but effective surface passivation is critical due to their large surface-to-volume ratio. For InP such passivation has proven particularly difficult, with substantial depassivation generally observed following dielectric deposition on InP surfaces. We present a novel approach based on passivation with a phosphorus-rich interfacial oxide deposited using a low-temperature process, which is critical to avoid P-desorption. For this purpose we have chosen a PO x layer deposited in a plasma-assisted atomic layer deposition (ALD) system at room temperature. Since PO x is known to be hygroscopic and therefore unstable in atmosphere, we encapsulate this layer with a thin ALD Al 2 O 3 capping layer to form a PO x /Al 2 O 3 stack. This passivation scheme is capable of improving the photoluminescence (PL) efficiency of our state-of-the-art wurtzite (WZ) InP nanowires by a factor of ∼20 at low excitation. If we apply the rate equation analysis advocated by some authors, we derive a PL internal quantum efficiency (IQE) of 75% for our passivated wires at high excitation. Our results indicate that it is more reliable to calculate the IQE as the ratio of the integrated PL intensity at room temperature to that at 10 K. By this means we derive an IQE of 27% for the passivated wires at high excitation (>10 kW cm -2 ), which constitutes an unprecedented level of performance for undoped InP nanowires. This conclusion is supported by time-resolved PL decay lifetimes, which are also shown to be significantly higher than previously reported for similar wires. The passivation scheme displays excellent long-term stability (>7 months) and is additionally shown to substantially improve the thermal stability of InP surfaces (>300 °C), significantly expanding the temperature window for device processing. Such effective surface passivation is a key enabling technology for InP nanowire devices such as nanolasers and solar cells.

Effective Surface Passivation of InP Nanowires by Atomic-Layer-Deposited Al2O3 with POx Interlayer

PubMed Central

2017-01-01

III/V semiconductor nanostructures have significant potential in device applications, but effective surface passivation is critical due to their large surface-to-volume ratio. For InP such passivation has proven particularly difficult, with substantial depassivation generally observed following dielectric deposition on InP surfaces. We present a novel approach based on passivation with a phosphorus-rich interfacial oxide deposited using a low-temperature process, which is critical to avoid P-desorption. For this purpose we have chosen a POx layer deposited in a plasma-assisted atomic layer deposition (ALD) system at room temperature. Since POx is known to be hygroscopic and therefore unstable in atmosphere, we encapsulate this layer with a thin ALD Al2O3 capping layer to form a POx/Al2O3 stack. This passivation scheme is capable of improving the photoluminescence (PL) efficiency of our state-of-the-art wurtzite (WZ) InP nanowires by a factor of ∼20 at low excitation. If we apply the rate equation analysis advocated by some authors, we derive a PL internal quantum efficiency (IQE) of 75% for our passivated wires at high excitation. Our results indicate that it is more reliable to calculate the IQE as the ratio of the integrated PL intensity at room temperature to that at 10 K. By this means we derive an IQE of 27% for the passivated wires at high excitation (>10 kW cm–2), which constitutes an unprecedented level of performance for undoped InP nanowires. This conclusion is supported by time-resolved PL decay lifetimes, which are also shown to be significantly higher than previously reported for similar wires. The passivation scheme displays excellent long-term stability (>7 months) and is additionally shown to substantially improve the thermal stability of InP surfaces (>300 °C), significantly expanding the temperature window for device processing. Such effective surface passivation is a key enabling technology for InP nanowire devices such as nanolasers and solar cells. PMID:28885032

Improvement of cationic albumin conjugated pegylated nanoparticles holding NC-1900, a vasopressin fragment analog, in memory deficits induced by scopolamine in mice.

PubMed

Xie, Yue-Ling; Lu, Wei; Jiang, Xin-Guo

2006-10-02

NC-1900, an active fragment analog of arginine vasopressin [arginine vasopressin-(4-9)], has proved to be capable of improving the spatial memory deficits and the impairments in passive avoidance test. In this study, a novel drug carrier for brain delivery, cationic bovine serum albumin conjugated pegylated nanoparticles (CBSA-NPs) holding NC-1900, was developed and its improvement on scopolamine-induced memory deficits was investigated in mice using the platform-jumping avoidance test. CBSA-NPs loaded with NC-1900 in spherical shape and uniform size below 100 nm were prepared by the double emulsion/solvent evaporation procedure, and the zeta potential of CBSA-NPs was about -8mV with the loading capacity of NC-1900 around 0.46%. The in vitro study showed that approximately 10% NC-1900 was released from CBSA-NPs in pH 7.4 phosphate buffer saline (PBS) during 56 h incubation with about 15% NC-1900 released in pH 4.0 PBS during 7 days, indicating the sustained release of this carrier. Furthermore, the half-life of NC-1900 loaded in CBSA-NPs in plasma was about 78 h, which was 4-fold longer than that of free NC-1900 (19 h). The active avoidance behavioral results showed that the s.c. administration of NC-1900 tended to improve memory deficits, but the difference did not present any statistical significance, whereas this peptide failed to produce any positive effects by i.v. administration. However, the i.v. injection of CBSA-NPs loaded with NC-1900 greatly improved memory impairments to a normal level, but the efficacy was slight if the loaded nanoparticles (NPs) were exclusive of the conjugation of CBSA, indicating that CBSA-NP was a promising brain delivery carrier for NC-1900 with CBSA as a potent brain targetor. It was concluded that CBSA-NP loaded with NC-1900 was potentially efficacious in the treatment of memory deficits via i.v. administration.

TESTING OF INDOOR RADON REDUCTION TECHNIQUES IN 19 MARYLAND HOUSES

EPA Science Inventory

The report gives results of testing of indoor radon reduction techniques in 19 existing houses in Maryland. The focus was on passive measures: various passive soil depressurization methods, where natural wind and temperature effects are utilized to develop suction in the system; ...

Relationship between changes in rat behavior and integral biochemical indexes determined by laser correlation spectroscopy after photothrombosis of the prefrontal cortex.

PubMed

Romanova, G A; Shakova, F M; Kovaleva, O I; Pivovarov, V V; Khlebnikova, N N; Karganov, M Yu

2004-02-01

Experiments on rats showed that Noopept improved retention and retrieval of conditioned passive avoidance response after phototrombosis of the prefrontal cortex (a procedure impairing retention of memory traces). The impairment of mnesic functions was accompanied by changes in integral biochemical indexes of the plasma determined by laser correlation spectroscopy. Treatment of behavioral disorders with Noopepet normalized biochemical indexes.

Nootropic and antiamnestic effects of tenoten (pediatric formulation) in immature rat pups.

PubMed

Voronina, T A; Molodavkin, G M; Borodavkina, M V; Kheyfets, I A; Dugina, Yu L; Sergeeva, S A

2009-09-01

The antiamnestic effects of tenoten (pediatric formulation) was demonstrated on the model of scopolamine-induced amnesia of passive avoidance reflex and the nootropic effect of this preparation was demonstrated on the model of incomplete conditioning and in rat pups with experimental attention deficit syndrome. The efficiency of the preparation was comparable to that of piracetam and phenibut and even surpassed it by some parameters.

A stereo-vision hazard-detection algorithm to increase planetary lander autonomy

NASA Astrophysics Data System (ADS)

Woicke, Svenja; Mooij, Erwin

2016-05-01

For future landings on any celestial body, increasing the lander autonomy as well as decreasing risk are primary objectives. Both risk reduction and an increase in autonomy can be achieved by including hazard detection and avoidance in the guidance, navigation, and control loop. One of the main challenges in hazard detection and avoidance is the reconstruction of accurate elevation models, as well as slope and roughness maps. Multiple methods for acquiring the inputs for hazard maps are available. The main distinction can be made between active and passive methods. Passive methods (cameras) have budgetary advantages compared to active sensors (radar, light detection and ranging). However, it is necessary to proof that these methods deliver sufficiently good maps. Therefore, this paper discusses hazard detection using stereo vision. To facilitate a successful landing not more than 1% wrong detections (hazards that are not identified) are allowed. Based on a sensitivity analysis it was found that using a stereo set-up at a baseline of ≤ 2 m is feasible at altitudes of ≤ 200 m defining false positives of less than 1%. It was thus shown that stereo-based hazard detection is an effective means to decrease the landing risk and increase the lander autonomy. In conclusion, the proposed algorithm is a promising candidate for future landers.

The memory-ameliorating effects of Artemisia princeps var. orientalis against cholinergic dysfunction in mice.

PubMed

Liu, Xiaotong; Kim, Dong Hyun; Kim, Jong Min; Park, Se Jin; Cai, Mudan; Jang, Dae Sik; Ryu, Jong Hoon

2012-01-01

Artemisia princeps var. orientalis (Compositae) is widely distributed in China, Japan and Korea and is known to have anti-inflammatory and anti-oxidative activities. The ethyl acetate fraction of ethanolic extract of A. princeps var. orientalis (AEA) was found to inhibit acetylcholinesterase activity in a dose-dependent manner in vitro (IC(50) value: 541.4 ± 67.5 μg/ml). Therefore, we investigated the effects of AEA on scopolamine-induced learning and memory impairment using the passive avoidance, the Y-maze, and the Morris water maze tasks in mice. AEA (100 or 200 mg/kg, p.o.) significantly ameliorated scopolamine-induced cognitive impairments in the passive avoidance and Y-maze tasks (p < 0.05). In the Morris water maze task, AEA (200 mg/kg, p.o.) significantly shortened escape latencies in training trials and increased both swimming time spent in the target zone and probe crossing numbers during the probe trial as compared with scopolamine-treated mice (p < 0.05). Additionally, the ameliorating effect of AEA on scopolamine-induced memory impairment was antagonized by a subeffective dose of MK-801. These results suggest that AEA could be an effective treatment against cholinergic dysfunction and its effect is mediated by the enhancement of the cholinergic neurotransmitter system via NMDA receptor signaling or acetylcholinesterase inhibition.

A Passive Earth-Entry Capsule for Mars Sample Return

NASA Technical Reports Server (NTRS)

Mitcheltree, Robert A.; Kellas, Sotiris

1999-01-01

A combination of aerodynamic analysis and testing, aerothermodynamic analysis, structural analysis and testing, impact analysis and testing, thermal analysis, ground characterization tests, configuration packaging, and trajectory simulation are employed to determine the feasibility of an entirely passive Earth entry capsule for the Mars Sample Return mission. The design circumvents the potential failure modes of a parachute terminal descent system by replacing that system with passive energy absorbing material to cushion the Mars samples during ground impact. The suggested design utilizes a spherically blunted 45-degree half-angle cone forebody with an ablative heat shield. The primary structure is a hemispherical, composite sandwich enclosing carbon foam energy absorbing material. Though no demonstration test of the entire system is included, results of the tests and analysis presented indicate that the design is a viable option for the Mars Sample Return Mission.

Nicotine cut-off value in human hair as a tool to distinguish active from passive smokers: A cross-sectional study in Japanese men.

PubMed

Tsuji, Masayoshi; Kanda, Hideyuki; Hayakawa, Takehito; Mori, Yayoi; Ito, Teruna; Hidaka, Tomoo; Kakamu, Takeyasu; Kumagai, Tomohiro; Osaki, Yoneatsu; Kawazoe, Miki; Sato, Sei; Fukushima, Tetsuhito

2017-07-19

Nicotine concentration in hair is a useful marker of tobacco exposure. Detection of nicotine in the hair of non-smokers indicates passive smoking. Accurate measurement of nicotine among active and passive smokers can help in smoking cessation programs or programs designed to prevent secondhand smoke exposure. To establish, using high-performance liquid chromatography-ultraviolet detection (HPLC/UV), a hair nicotine cut-off value to distinguish active from passive smokers. Hair samples were collected from randomly chosen Japanese men (n= 192) between 2009 and 2011. Nicotine and cotinine levels in hair were measured using HPLC/UV with column-switching. T-tests and chi-square tests were performed to compare active and passive smokers, while receiver operating characteristic curves were used to evaluate the effectiveness of the cut-off value. There were 69 active smokers and 123 passive smokers. The nicotine and cotinine concentrations in hair were significantly higher in active than in passive smokers (p< 0.01). The area under the curve for nicotine was 0.92. A hair nicotine cut-off value of 5.68 ng/mg, with a sensitivity of 94.2% and specificity of 87.0%, was identified as the optimal cut-off value for separating active from passive smokers. Nicotine and cotinine concentrations in hair clearly distinguished active from passive smokers.

Active prospective control is required for effective sensorimotor learning.

PubMed

Snapp-Childs, Winona; Casserly, Elizabeth; Mon-Williams, Mark; Bingham, Geoffrey P

2013-01-01

Passive modeling of movements is often used in movement therapy to overcome disabilities caused by stroke or other disorders (e.g. Developmental Coordination Disorder or Cerebral Palsy). Either a therapist or, recently, a specially designed robot moves or guides the limb passively through the movement to be trained. In contrast, action theory has long suggested that effective skill acquisition requires movements to be actively generated. Is this true? In view of the former, we explicitly tested the latter. Previously, a method was developed that allows children with Developmental Coordination Disorder to produce effective movements actively, so as to improve manual performance to match that of typically developing children. In the current study, we tested practice using such active movements as compared to practice using passive movement. The passive movement employed, namely haptic tracking, provided a strong test of the comparison, one that showed that the mere inaction of the muscles is not the problem. Instead, lack of prospective control was. The result was no effective learning with passive movement while active practice with prospective control yielded significant improvements in performance.

PANDA asymmetric-configuration passive decay heat removal test results

DOE Office of Scientific and Technical Information (OSTI.GOV)

Fischer, O.; Dreier, J.; Aubert, C.

1997-12-01

PANDA is a large-scale, low-pressure test facility for investigating passive decay heat removal systems for the next generation of LWRs. In the first series of experiments, PANDA was used to examine the long-term LOCA response of the Passive Containment Cooling System (PCCS) for the General Electric (GE) Simplified Boiling Water Reactor (SBWR). The test objectives include concept demonstration and extension of the database available for qualification of containment codes. Also included is the study of the effects of nonuniform distributions of steam and noncondensable gases in the Dry-well (DW) and in the Suppression Chamber (SC). 3 refs., 9 figs.

Optimization of Controllable Factors in the Aluminum Silicon Eutectic Paste and Rear Silicon Nitride Mono-Passivation Layer of PERC Solar Cells

NASA Astrophysics Data System (ADS)

Park, Sungeun; Park, Hyomin; Kim, Dongseop; Yang, JungYup; Lee, Dongho; Kim, Young-Su; Kim, Hyun-Jong; Suh, Dongchul; Min, Byoung Koun; Kim, Kyung Nam; Park, Se Jin; Kim, Donghwan; Lee, Hae-Seok; Nam, Junggyu; Kang, Yoonmook

2018-05-01

Passivated emitter and rear contact (PERC) is a promising technology owing to high efficiency can be achieved with p-type wafer and their easily applicable to existing lines. In case of using p-type mono wafer, 0.5-1% efficiency increase is expected with PERC technologies compared to existing Al BSF solar cells, while for multi-wafer solar cells it is 0.5-0.8%. We addressed the optimization of PERC solar cells using the Al paste. The paste was prepared from the aluminum-silicon alloy with eutectic composition to avoid the formation of voids that degrade the open-circuit voltage. The glass frit of the paste was changed to improve adhesion. Scanning electron microscopy revealed voids and local back surface field between the aluminum electrode and silicon base. We confirmed the conditions on the SiNx passivation layer for achieving higher efficiency and better adhesion for long-term stability. The cell characteristics were compared across cells containing different pastes. PERC solar cells with the Al/Si eutectic paste exhibited the efficiency of 19.6%.

The effects of green Ocimum basilicum hydroalcoholic extract on retention and retrieval of memory in mice

PubMed Central

Sarahroodi, Shadi; Esmaeili, Somayyeh; Mikaili, Peyman; Hemmati, Zahra; Saberi, Yousof

2012-01-01

The purpose of this study was evaluation of green Ocimum basilicum (sweet basil) hydroalcoholic extract on memory retention and retrieval of mice by using passive avoidance apparatus. For this purpose, after weighting, coding and classifying the mice, they were grouped (n = 8) as follow as: test groups (electric shock plus sweet basil extract by doses: 100, 200, 400 and 800 mg/kg, i.p.), control group (Only electric shock) and blank group (electric shock plus normal saline). In all mentioned groups delay time of leaving the platform for both retention and retrieval test of memory was measured. In retention test, sweet basil extract was administered immediately after receiving electric shock and in retrieval test it was administered 24 hours after receiving electric shock. The results indicated that hydroalcoholic extract of green Ocimum basilicum significantly (P < 0.05) increased memory retention. The best response was achieved with 400 mg/Kg of the extract. Also, results showed that sweet basil extract significantly (P < 0.05) increased memory retrieval and the best result was achieved with 400 mg/Kg too. It can be concluded that memory enhancing effects of green Ocimum basilicum is because of antioxidant activity of flavonoids, tannins and terpenoids. PMID:23661866

Comprehensive neuromechanical assessment in stroke patients: reliability and responsiveness of a protocol to measure neural and non-neural wrist properties.

PubMed

van der Krogt, Hanneke; Klomp, Asbjørn; de Groot, Jurriaan H; de Vlugt, Erwin; van der Helm, Frans Ct; Meskers, Carel Gm; Arendzen, J Hans

2015-03-13

Understanding movement disorder after stroke and providing targeted treatment for post stroke patients requires valid and reliable identification of biomechanical (passive) and neural (active and reflexive) contributors. Aim of this study was to assess test-retest reliability of passive, active and reflexive parameters and to determine clinical responsiveness in a cohort of stroke patients with upper extremity impairments and healthy volunteers. Thirty-two community-residing chronic stroke patients with an impairment of an upper limb and fourteen healthy volunteers were assessed with a comprehensive neuromechanical assessment protocol consisting of active and passive tasks and different stretch reflex-eliciting measuring velocities, using a haptic manipulator and surface electromyography of wrist flexor and extensor muscles (Netherlands Trial Registry number NTR1424). Intraclass correlation coefficients (ICC) and Standard Error of Measurement were calculated to establish relative and absolute test-retest reliability of passive, active and reflexive parameters. Clinical responsiveness was tested with Kruskal Wallis test for differences between groups. ICC of passive parameters were fair to excellent (0.45 to 0.91). ICC of active parameters were excellent (0.88-0.99). ICC of reflexive parameters were fair to good (0.50-0.74). Only the reflexive loop time of the extensor muscles performed poor (ICC 0.18). Significant differences between chronic stroke patients and healthy volunteers were found in ten out of fourteen parameters. Passive, active and reflexive parameters can be assessed with high reliability in post-stroke patients. Parameters were responsive to clinical status. The next step is longitudinal measurement of passive, active and reflexive parameters to establish their predictive value for functional outcome after stroke.

Development of heat-storage building materials for passive-solar applications

NASA Astrophysics Data System (ADS)

Fletcher, J. W.

A heat storage building material to be used for passive solar applications and general load leveling within building spaces was developed. Specifically, PCM-filled plastic panels are to be developed as wallboard and ceiling panels. Three PCMs (CaCl2, 6H2O; Na2SO4, 10H2O; LiNO3, 3H2O are to be evaluated for use in the double walled, hollow channeled plastic panels. Laboratory development of the panels will include determination of filling and sealing techniques, behavior of the PCMs, container properties and materials compatibility. Testing will include vapor transmission, thermal cycle, dynamic performance, accelerated life and durability tests. In addition to development and testing, an applications analysis will be performed for specific passive solar applications. Conceptual design of a single family passive solar residence will be prepared and performance evaluated. Screening of the three PCM candidates is essentially complete.

Model stream channel testing of a UV-transparent polymer-based passive sampler for ultra-low-cost water screening applications

EPA Science Inventory

Passive samplers are increasingly being considered for analyses of waters for screening applications, to monitor for the presence of unwanted chemical compounds. Passive samplers typically work by accumulating and concentrating chemicals from the surrounding water over time, all...

FFTF Passive Safety Test Data for Benchmarks for New LMR Designs

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wootan, David W.; Casella, Andrew M.

Liquid Metal Reactors (LMRs) continue to be considered as an attractive concept for advanced reactor design. Software packages such as SASSYS are being used to im-prove new LMR designs and operating characteristics. Significant cost and safety im-provements can be realized in advanced liquid metal reactor designs by emphasizing inherent or passive safety through crediting the beneficial reactivity feedbacks associ-ated with core and structural movement. This passive safety approach was adopted for the Fast Flux Test Facility (FFTF), and an experimental program was conducted to characterize the structural reactivity feedback. The FFTF passive safety testing pro-gram was developed to examine howmore » specific design elements influenced dynamic re-activity feedback in response to a reactivity input and to demonstrate the scalability of reactivity feedback results to reactors of current interest. The U.S. Department of En-ergy, Office of Nuclear Energy Advanced Reactor Technology program is in the pro-cess of preserving, protecting, securing, and placing in electronic format information and data from the FFTF, including the core configurations and data collected during the passive safety tests. Benchmarks based on empirical data gathered during operation of the Fast Flux Test Facility (FFTF) as well as design documents and post-irradiation examination will aid in the validation of these software packages and the models and calculations they produce. Evaluation of these actual test data could provide insight to improve analytical methods which may be used to support future licensing applications for LMRs« less

PSD Camera Based Position and Posture Control of Redundant Robot Considering Contact Motion

NASA Astrophysics Data System (ADS)

Oda, Naoki; Kotani, Kentaro

The paper describes a position and posture controller design based on the absolute position by external PSD vision sensor for redundant robot manipulator. The redundancy enables a potential capability to avoid obstacle while continuing given end-effector jobs under contact with middle link of manipulator. Under contact motion, the deformation due to joint torsion obtained by comparing internal and external position sensor, is actively suppressed by internal/external position hybrid controller. The selection matrix of hybrid loop is given by the function of the deformation. And the detected deformation is also utilized in the compliant motion controller for passive obstacle avoidance. The validity of the proposed method is verified by several experimental results of 3link planar redundant manipulator.

Investigation of passive films on nickel Alloy 690 in lead-containing environments

NASA Astrophysics Data System (ADS)

Peng, B.; Lu, B. T.; Luo, J. L.; Lu, Y. C.; Ma, H. Y.

2008-09-01

Passive films formed on Alloy UNS N06690 were investigated in simulated crevice chemistries. It was found the role of lead in corrosion processes is strongly dependent on the pH value of the testing solutions. At pH 1.5 the effect of lead is narrowly noticeable; while at pH 12.7, lead has a significant influence on the electrochemical performance of alloy UNS N06690. The lead alters the surface morphologies at both pH and account for higher hydroxide content in the surface film at pH 12.7. The lead incorporation hinders the formation of spinel oxides during the passivation in alkaline solution. Nanoindentation tests indicate a significant lead-induced degradation in the mechanical properties of passive films. The passivation degradation is attributed to detrimental effects of lead via interrupting the dehydration process and hindering the formation of protective layers on the alloy surface.

The influence of active and passive smoking on the cardiorespiratory fitness of adults.

PubMed

de Borba, Andresa Thier; Jost, Renan Trevisan; Gass, Ricardo; Nedel, Fúlvio Borges; Cardoso, Dannuey Machado; Pohl, Hildegard Hedwig; Reckziegel, Miriam Beatris; Corbellini, Valeriano Antonio; Paiva, Dulciane Nunes

2014-01-01

The aim of this study was to analyze the influence of active and passive smoking on cardiorespiratory responses in asymptomatic adults during a sub-maximal-exertion incremental test. The participants (n = 43) were divided into three different groups: active smokers (n = 14; aged 36.5 ± 8 years), passive smokers (n = 14; aged 34.6 ± 11.9 years) and non-smokers (n = 15; aged 30 ± 8.1 years). They all answered the Test for Nicotine Dependence and underwent anthropometric evaluation, spirometry and ergospirometry according to the Bruce Treadmill Protocol. VO2max differed statistically between active and non-smokers groups (p < 0.001) and between non-smokers and passive group (p=0.022). However, there was no difference between the passive and active smokers groups (p=0.053). Negative and significant correlations occurred between VO2max and age (r = - 0.401, p = 0.044), percentage of body fat (r = - 0.429, p = 0.011), and waist circumference (WC) (r = - 0.382, p = 0.025). VO2max was significantly higher in non-smokers compared to active smokers and passive smokers. However, the VO2max of passive smokers did not differ from active smokers.

Coastal California's Fog Aerobiology and Ecology: Designing and Testing an Optimal Passive Impactor Collection Unit

NASA Astrophysics Data System (ADS)

Gentry, D.; Whinnery, J. T.; Ly, V. T.; Travers, S. V.; Sagaga, J.; Dahlgren, R. P.

2017-12-01

Microorganisms play a major role in our biosphere due to their ability to alter water, carbon and other geochemical cycles. Fog and low-level cloud water can play a major role in dispersing and supporting such microbial diversity. An ideal region to gather these microorganisms for characterization is the central coast of California, where dense fog is common. Fog captured from an unmanned aerial vehicle (UAV) at different altitudes will be analyzed to better understand the nature of microorganisms in the lower atmosphere and their potential geochemical impacts. The capture design consists of a square-meter hydrophobic mesh that hangs from a carbon fiber rod attached to a UAV. The DJI M600, a hexacopter, will be utilized as the transport for the payload, the passive impactor collection unit (PICU). The M600 will hover in a fog bank at altitudes between 10 and 100 m collecting water samples via the PICU. A computational flow dynamics (CFD) model will optimize the PICU's size, shape and placement for maximum capture efficiency and to avoid contamination from the UAV downwash. On board, there will also be an altitude, temperature and barometric pressure sensor whose output is logged to an SD card. A scale model of the PICU has been tested with several different types of hydrophobic meshes in a fog chamber at 90-95% humidity; polypropylene was found to capture the fog droplets most efficiently at a rate of .0042 g/cm2/hour. If the amount collected is proportional to the area of mesh, the estimated amount of water collected under optimal fog and flight conditions by the impactor is 21.3 g. If successful, this work will help identify the organisms living in the lower atmosphere as well as their potential geochemical impacts.

Elastic Velocity Updating through Image-Domain Tomographic Inversion of Passive Seismic Data

NASA Astrophysics Data System (ADS)

Witten, B.; Shragge, J. C.

2014-12-01

Seismic monitoring at injection sites (e.g., CO2sequestration, waste water disposal, hydraulic fracturing) has become an increasingly important tool for hazard identification and avoidance. The information obtained from this data is often limited to seismic event properties (e.g., location, approximate time, moment tensor), the accuracy of which greatly depends on the estimated elastic velocity models. However, creating accurate velocity models from passive array data remains a challenging problem. Common techniques rely on picking arrivals or matching waveforms requiring high signal-to-noise data that is often not available for the magnitude earthquakes observed over injection sites. We present a new method for obtaining elastic velocity information from earthquakes though full-wavefield wave-equation imaging and adjoint-state tomography. The technique exploits images of the earthquake source using various imaging conditions based upon the P- and S-wavefield data. We generate image volumes by back propagating data through initial models and then applying a correlation-based imaging condition. We use the P-wavefield autocorrelation, S-wavefield autocorrelation, and P-S wavefield cross-correlation images. Inconsistencies in the images form the residuals, which are used to update the P- and S-wave velocity models through adjoint-state tomography. Because the image volumes are constructed from all trace data, the signal-to-noise in this space is increased when compared to the individual traces. Moreover, it eliminates the need for picking and does not require any estimation of the source location and timing. Initial tests show that with reasonable source distribution and acquisition array, velocity anomalies can be recovered. Future tests will apply this methodology to other scales from laboratory to global.

Effect of Passive, Active and Combined Warm up on Lower Limb Muscle Performance and Dynamic Stability in Recreational Sports Players.

PubMed

Gogte, Kedar; Srivastav, Prateek; Miyaru, Ganesh Balthillaya

2017-03-01

Warm up is an activity that is done before a sports activity. The warm up can be done actively and passively. The preferred mode is active warm up in athletes. There are inconclusive effects of passive warm up compared with an active warm up on short term muscle performance. The cumulative effect of passive and active warm up on muscle performance and dynamic stability is not known. To find out the effects of passive, active and combined warm up on lower limb muscle performance and dynamic stability in recreational sports players. A randomized crossover study was done on 19 recreational lower limb dominant sports players. Three different warm ups were included in the study passive, active and combined. Active warm up included series of activities like cycling, leg press, jump squats, squat jumps while passive warm up included application of moist heat for a period of 20 minutes on lower limb muscles. Combined warm up included both passive and active warm up. Six different sequences were made from these three warm ups. Subjects were screened and allotted into different groups based on the six warm up sequences after sequence randomization with 48 hours wash out period. After every warm up session Vertical Jump Test (VJT) and Star Excursion Balance Test (SEBT) was performed and results were recorded. Study duration was one year and six months. There was no difference noticed in both the outcome measures. Mean and SD values for passive, active and combined warm up are 47.62±9.64, 48.50±10.16 and 48.87±10.70 respectively in Vertical Jump Test (VJT) and 85.43±8.61, 85.17±8.60 and 85.17±8.38 respectively for SEBT. The p-value for mean difference between passive-active, active-combined, combined-passive are 0.67, 1.00, 0.51 respectively, for VJT and 1.00, 1.00, 1.00 respectively for SEBT. All warm ups are equally effective in short term sports performance.

Effect of Passive, Active and Combined Warm up on Lower Limb Muscle Performance and Dynamic Stability in Recreational Sports Players

PubMed Central

Gogte, Kedar; Miyaru, Ganesh Balthillaya

2017-01-01

Introduction Warm up is an activity that is done before a sports activity. The warm up can be done actively and passively. The preferred mode is active warm up in athletes. There are inconclusive effects of passive warm up compared with an active warm up on short term muscle performance. The cumulative effect of passive and active warm up on muscle performance and dynamic stability is not known. Aim To find out the effects of passive, active and combined warm up on lower limb muscle performance and dynamic stability in recreational sports players. Materials and Methods A randomized crossover study was done on 19 recreational lower limb dominant sports players. Three different warm ups were included in the study passive, active and combined. Active warm up included series of activities like cycling, leg press, jump squats, squat jumps while passive warm up included application of moist heat for a period of 20 minutes on lower limb muscles. Combined warm up included both passive and active warm up. Six different sequences were made from these three warm ups. Subjects were screened and allotted into different groups based on the six warm up sequences after sequence randomization with 48 hours wash out period. After every warm up session Vertical Jump Test (VJT) and Star Excursion Balance Test (SEBT) was performed and results were recorded. Study duration was one year and six months. Results There was no difference noticed in both the outcome measures. Mean and SD values for passive, active and combined warm up are 47.62±9.64, 48.50±10.16 and 48.87±10.70 respectively in Vertical Jump Test (VJT) and 85.43±8.61, 85.17±8.60 and 85.17±8.38 respectively for SEBT. The p-value for mean difference between passive-active, active-combined, combined-passive are 0.67, 1.00, 0.51 respectively, for VJT and 1.00, 1.00, 1.00 respectively for SEBT. Conclusion All warm ups are equally effective in short term sports performance. PMID:28511496

Passive Isolators for use on the International Space Station

NASA Technical Reports Server (NTRS)

Houston, Janice; Gattis, Christy

2003-01-01

The value of the International Space Station (ISS) as a premier microgravity environment is currently at risk due to structure-borne vibration. The vibration sources are varied and include crew activities such as exercising or simply moving from module to module, and electro- mechanical equipment such as fans and pumps. Given such potential degradation of usable microgravity, anything that can be done to dampen vibration on-orbit will significantly benefit microgravity users. Most vibration isolation schemes, both active and passive, have proven to be expensive - both operationally and from the cost of integrating isolation systems into primary/secondary structural interfaces (e.g., the ISS module/rack interface). Recently, passively absorptive materials have been tested at the bolt interfaces between the operating equipment and support structure (secondary/tertiary structural interfaces). The results indicate that these materials may prove cost-effective in mitigating the vibrational problems of the ISS. We report herein tests of passive absorbers placed at the interface of a vibration-inducing component: the Development Distillation Assembly, a subassembly of the Urine Processing Assembly, which is a rotating centrifuge and cylinder assembly attached to a mounting plate. Passive isolators were installed between this mounting plate and its support shelf. Three materials were tested: BISCO HT-800, Sorbothane 30 and Sorbothane 50, plus a control test with a hard shim. In addition, four distinct combinations of the HT-800 and Sorbothane 50 were tested. Results show a significant (three orders of magnitude) reduction of transmitted energy, as measured in power spectral density (PSD), using the isolation materials. It is noted, however, that passive materials cannot prevent the transmission of very strong forces or absorb the total energy induced from structural resonances.

Small Radioisotope Power System Testing at NASA Glenn Research Center

NASA Technical Reports Server (NTRS)

Dugala, Gina; Bell, Mark; Oriti, Salvatore; Fraeman, Martin; Frankford, David; Duven, Dennis

2013-01-01

In April 2009, NASA Glenn Research Center (GRC) formed an integrated product team (IPT) to develop a Small Radioisotope Power System (SRPS) utilizing a single Advanced Stirling Convertor (ASC) with passive balancer. A single ASC produces approximately 80 We making this system advantageous for small distributed lunar science stations. The IPT consists of Sunpower, Inc., to provide the single ASC with a passive balancer, The Johns Hopkins University Applied Physics Laboratory (JHUAPL) to design an engineering model Single Convertor Controller (SCC) for an ASC with a passive balancer, and NASA GRC to provide technical support to these tasks and to develop a simulated lunar lander test stand. The single ASC with a passive balancer, simulated lunar lander test stand, and SCC were delivered to GRC and were tested as a system. The testing sequence at GRC included SCC fault tolerance, integration, electromagnetic interference (EMI), vibration, and extended operation testing. The SCC fault tolerance test characterized the SCCs ability to handle various fault conditions, including high or low bus power consumption, total open load or short circuit, and replacing a failed SCC card while the backup maintains control of the ASC. The integrated test characterized the behavior of the system across a range of operating conditions, including variations in cold-end temperature and piston amplitude, including the emitted vibration to both the sensors on the lunar lander and the lunar surface. The EMI test characterized the AC and DC magnetic and electric fields emitted by the SCC and single ASC. The vibration test confirms the SCCs ability to control the single ASC during launch. The extended operation test allows data to be collected over a period of thousands of hours to obtain long term performance data of the ASC with a passive balancer and the SCC. This paper will discuss the results of each of these tests.

Age differences in emotion regulation effort: Pupil response distinguishes reappraisal and distraction for older but not younger adults.

PubMed

Martins, Bruna; Florjanczyk, Jan; Jackson, Nicholas J; Gatz, Margaret; Mather, Mara

2018-03-01

In previous research, older adults show greater emotional benefits from distracting themselves than from reappraising an event when strategically regulating emotion. Older adults also demonstrate an attentional preference to avoid, while younger adults show a bias toward approaching negative stimuli. This suggests a possible age-related differentiation of cognitive effort across approach and avoidance of negative stimuli during emotion regulation. In this study, we tracked cognitive effort via pupil dilation during the use of distraction (avoidance) and reappraisal (approach) strategies across age. Forty-eight younger adults (M = 20.94, SD = 1.78; 19 men) and 48 older adults (M = 68.82, SD = 5.40; 15 men) viewed a slideshow of negative images and were instructed to distract, reappraise, or passively view each image. Older adults showed greater pupil dilation during reappraisal than distraction, but younger adults displayed no difference between conditions-an effect that survived when controlling for gaze patterns. Gaze findings revealed that older adults looked less within images during active emotion regulation compared with passive viewing (no difference between distraction and reappraisal), and younger adults showed no difference across strategies. Younger adults gazed less within the most emotional image areas during distraction, but this did not significantly contribute to pupil response. Our findings support that distraction is less cognitively effortful than reinterpreting negative information in later life. These findings could be explained by older adults' motivational bias to disengage from negative information because of the age-related positivity effect, or compensation for decreased working memory resources across the life span. (PsycINFO Database Record (c) 2018 APA, all rights reserved).

A new structure for comparing surface passivation materials of GaAs solar cells

NASA Technical Reports Server (NTRS)

Desalvo, Gregory C.; Barnett, Allen M.

1989-01-01

The surface recombination velocity (S sub rec) for bare GaAs is typically as high as 10 to the 6th power to 10 to the 7th power cm/sec, which dramatically lowers the efficiency of GaAs solar cells. Early attempts to circumvent this problem by making an ultra thin junction (xj less than .1 micron) proved unsuccessful when compared to lowering S sub rec by surface passivation. Present day GaAs solar cells use an GaAlAs window layer to passivate the top surface. The advantages of GaAlAs in surface passivation are its high bandgap energy and lattice matching to GaAs. Although GaAlAs is successful in reducing the surface recombination velocity, it has other inherent problems of chemical instability (Al readily oxidizes) and ohmic contact formation. The search for new, more stable window layer materials requires a means to compare their surface passivation ability. Therefore, a device structure is needed to easily test the performance of different passivating candidates. Such a test device is described.

Enhancing Classroom Participation of Rural Trainee Teachers of English through Use of Action Research: A Reflecton from a Chinese Teacher Trainer's Perspective

ERIC Educational Resources Information Center

Ping, Wang

2015-01-01

A common problem for Chinese teacher trainers is coping with a passive class with silent trainee learners, when trainees tend to be unresponsive and avoid interactions with the trainer. This is especially true when a trainer seeks interactions in the process of training, such as asking questions to the class as a whole or expecting at least one…

Moral fixations: The role of moral integrity and social anxiety in the selective avoidance of social threat.

PubMed

Van Dillen, Lotte F; Enter, Dorien; Peters, Leonie P M; van Dijk, Wilco W; Rotteveel, Mark

2017-01-01

People derive their sense of belonging from perceptions of being a moral person. Research moreover suggests that social cues of rejection rapidly influence visual scanning, and result in avoidant gaze behavior, especially in socially anxious individuals. With the current eye-tracking experiment, we therefore examined whether moral integrity threats and affirmations influence selective avoidance of social threat, and how this varies with individual differences in social anxiety. Fifty-nine participants retrieved a memory of a past immoral, moral, or neutral act. Next, participants passively viewed angry, happy, and neutral faces, while we recorded how often they first fixated on the eyes. In addition, we administered the Liebowitz Social Anxiety Scale (1987). Participants first fixated less on angry eyes compared to happy or neutral eyes when their moral integrity was threatened, and this selective avoidance was enhanced with increasing social anxiety. Following a moral affirmation, however, participants no longer selectively avoided the eyes of angry faces, regardless of individual differences in social anxiety. The results thus suggest that both low and high socially anxious people adjust their social gaze behavior in response to threats and affirmations of their moral integrity, pointing to the importance of the social context when considering affective processing biases. Copyright © 2016 Elsevier B.V. All rights reserved.

Passive cannabis smoke exposure and oral fluid testing.

PubMed

Niedbala, Sam; Kardos, Keith; Salamone, Sal; Fritch, Dean; Bronsgeest, Matth; Cone, Edward J

2004-10-01

Oral fluid testing for Delta(9)-tetrahydrocannabinol (THC) provides a convenient means of detection of recent cannabis usage. In this study, the risk of positive oral fluid tests from passive cannabis smoke exposure was investigated by housing four cannabis-free volunteers in a small, unventilated, and sealed room with an approximate volume of 36 m(3). Five active cannabis smokers were also present in the room, and each smoked a single cannabis cigarette (1.75% THC). Cannabis smoking occurred over the first 20 min of the study session. All subjects remained in the room for approximately 4 h. Oral fluid specimens were collected with the Intercept DOA Oral Specimen Collection Device. Three urine specimens were collected (0, 20, and 245 min). In addition, three air samples were collected for measurement of THC content. All oral fluid specimens were screened by enzyme immunoassay (EIA) for cannabinoids (cutoff concentration = 3 ng/mL) and tested by gas chromatography-tandem mass spectrometry (GC-MS-MS) for THC (LOQ/LOD = 0.75 ng/mL). All urine specimens were screened by EIA for cannabinoids (cutoff concentration = 50 ng/mL) and tested by GC-MS-MS for THCCOOH (LOQ/LOD = 1 ng/mL). Air samples were measured for THC by GC-MS (LOD = 1 ng/L). A total of eight oral fluid specimens (collected 20 to 50 min following initiation of smoking) from the four passive subjects screened and confirmed positive for THC at concentrations ranging from 3.6 to 26.4 ng/mL. Two additional specimens from one passive subject, collected at 50 and 65 min, screened negative but contained THC in concentrations of 4.2 and 1.1 ng/mL, respectively. All subsequent specimens for passive participants tested negative by EIA and GC-MS-MS for the remainder of the 4-h session. In contrast, oral fluid specimens collected from the five cannabis smokers generally screened and confirmed positive for THC throughout the session at concentrations substantially higher than observed for passive subjects. Urine specimens from active cannabis smokers also screened and confirmed positive at conventional cutoff concentrations. A biphasic pattern of decline for THC was observed in oral fluid specimens collected from cannabis smokers, whereas a linear decline was seen for passive subjects suggesting that initial oral fluid contamination is cleared rapidly and is followed by THC sequestration in the oral mucosa. It is concluded that the risk of positive oral fluid tests from passive cannabis smoke inhalation is limited to a period of approximately 30 min following exposure.

Preliminary Results on the Use of Leather Chrome Shavings for Air Passive Sampling

PubMed Central

Sanjuán-Herráez, D.; Chabaane, L.; Tahiri, S.; Pastor, A.; de la Guardia, M.

2012-01-01

A new passive sampler based on low-density polyethylene (LDPE) layflat tube filled with chrome shavings from tannery waste residues was evaluated to determine volatile organic compounds (VOCs) in indoor and outdoor areas. VOCs were directly determined by head space-gas chromatography-mass spectrometry (HS-GC-MS) without any pretreatment of the sampler and avoiding the use of solvents. Limit of detection values ranging from 20 to 75 ng sampler−1 and good repeatability values were obtained for VOCs under study with relative standard deviation values from 2.8 to 9.6% except for carbon disulfide for which it was 22.5%. The effect of the amount of chrome shavings per sampler was studied and results were compared with those obtained using empty LDPE tubes, to demonstrate the capacity of chrome shavings to adsorb VOCs. PMID:22900233

Hazard avoidance via descent images for safe landing

NASA Astrophysics Data System (ADS)

Yan, Ruicheng; Cao, Zhiguo; Zhu, Lei; Fang, Zhiwen

2013-10-01

In planetary or lunar landing missions, hazard avoidance is critical for landing safety. Therefore, it is very important to correctly detect hazards and effectively find a safe landing area during the last stage of descent. In this paper, we propose a passive sensing based HDA (hazard detection and avoidance) approach via descent images to lower the landing risk. In hazard detection stage, a statistical probability model on the basis of the hazard similarity is adopted to evaluate the image and detect hazardous areas, so that a binary hazard image can be generated. Afterwards, a safety coefficient, which jointly utilized the proportion of hazards in the local region and the inside hazard distribution, is proposed to find potential regions with less hazards in the binary hazard image. By using the safety coefficient in a coarse-to-fine procedure and combining it with the local ISD (intensity standard deviation) measure, the safe landing area is determined. The algorithm is evaluated and verified with many simulated descent downward looking images rendered from lunar orbital satellite images.

A mental retardation gene, motopsin/neurotrypsin/prss12, modulates hippocampal function and social interaction

PubMed Central

Mitsui, Shinichi; Osako, Yoji; Yokoi, Fumiaki; Dang, Mai T.; Yuri, Kazunari; Li, Yuqing; Yamaguchi, Nozomi

2010-01-01

Motopsin is a mosaic serine protease secreted from neuronal cells in various brain regions including the hippocampus. The loss of motopsin function causes nonsyndromic mental retardation in humans and impairs long-term memory formation in Drosophila. To understand motopsin’s function in the mammalian brain, motopsin knockout mice were generated. Motopsin knockout mice did not have significant deficit in memory formation, as was tested using in the Morris water maze, passive avoidance, and Y-maze tests. A social recognition test showed that the motopsin knockout mice had the ability to recognize two stimulator mice, suggesting normal social memory. In a social novelty test, motopsin knockout mice spent a longer time investigating a familiar mouse than wild-type mice did. In a resident-intruder test, motopsin knockout mice showed prolonged social interaction compared to wild-type mice. Consistent with the behavioral deficit, spine density was significantly decreased on apical dendrites, but not on basal dendrites, of hippocampal pyramidal neurons of motopsin knockout mice. In contrast, pyramidal neurons at the cingulate cortex showed normal spine density. Spatial learning and social interaction induced the phosphorylation of cAMP responsive element binding protein (CREB) in hippocampal neurons of wild-type mice, whereas the phosphorylation of CREB was markedly decreased in mutant mouse brains. Our results indicate that an extracellular protease, motopsin, preferentially affects social behaviors, and modulates the functions of hippocampal neurons. PMID:20092579

A mental retardation gene, motopsin/neurotrypsin/prss12, modulates hippocampal function and social interaction.

PubMed

Mitsui, Shinichi; Osako, Yoji; Yokoi, Fumiaki; Dang, Mai T; Yuri, Kazunari; Li, Yuqing; Yamaguchi, Nozomi

2009-12-01

Motopsin is a mosaic serine protease secreted from neuronal cells in various brain regions, including the hippocampus. The loss of motopsin function causes nonsyndromic mental retardation in humans and impairs long-term memory formation in Drosophila. To understand motopsin's function in the mammalian brain, motopsin knockout (KO) mice were generated. Motopsin KO mice did not have significant deficits in memory formation, as tested using the Morris water maze, passive avoidance and Y-maze tests. A social recognition test showed that the motopsin KO mice had the ability to recognize two stimulator mice, suggesting normal social memory. In a social novelty test, motopsin KO mice spent a longer time investigating a familiar mouse than wild-type (WT) mice did. In a resident-intruder test, motopsin KO mice showed prolonged social interaction as compared with WT mice. Consistent with the behavioral deficit, spine density was significantly decreased on apical dendrites, but not on basal dendrites, of hippocampal pyramidal neurons of motopsin KO mice. In contrast, pyramidal neurons at the cingulate cortex showed normal spine density. Spatial learning and social interaction induced the phosphorylation of cAMP-responsive element-binding protein (CREB) in hippocampal neurons of WT mice, whereas the phosphorylation of CREB was markedly decreased in mutant mouse brains. Our results indicate that an extracellular protease, motopsin, preferentially affects social behaviors, and modulates the functions of hippocampal neurons.

Testing a passive revegetation approach for restoring coastal plain depression wetlands

Treesearch

Diane De Steven; Rebecca R. Sharitz; Julian H. Singer; Christopher D. Barton

2006-01-01

Restoration of coastal plain depressions, a biologically significant and threatened wetland type of the southeastern United States, has received little systematic research. Within the context of an experimental project designed to evaluate several restoration approaches, we tested whether successful revegetation can be achieved by passive methods (recruitment from seed...

Use of behavioral avoidance testing in natural resource damage assessment

USGS Publications Warehouse

Lipton, J.; Little, E.E.; Marr, J.C.A.; DeLonay, A.J.; Bengston, David A.; Henshel, Diane S.

1996-01-01

Natural Resource Damage Assessment (NRDA) provisions established under federal and state statutes enable natural resource trustees to recover compensation from responsible parties to restore injured natural resources. Behavioral avoidance testing with fish has been used in NRDAs to determine injuries to natural resources and to establish restoration thresholds. In this manuscript we evaluate the use of avoidance testing to NRDA. Specifically, we discuss potential “acceptance criteria” to evaluate the applicability and relevance of avoidance testing. These acceptance criteria include: (1) regulatory relevance, (2) reproducibility of testing, (3) ecological significance, (4) quality assurance/quality control, and (5) relevance to restoration. We discuss each of these criteria with respect to avoidance testing. Overall, we conclude that avoidance testing can be an appropriate, defensible, and desirable aspect of an NRDA.

Provocative mechanical tests of the peripheral nervous system affect the joint torque-angle during passive knee motion.

PubMed

Andrade, R J; Freitas, S R; Vaz, J R; Bruno, P M; Pezarat-Correia, P

2015-06-01

This study aimed to determine the influence of the head, upper trunk, and foot position on the passive knee extension (PKE) torque-angle response. PKE tests were performed in 10 healthy subjects using an isokinetic dynamometer at 2°/s. Subjects lay in the supine position with their hips flexed to 90°. The knee angle, passive torque, surface electromyography (EMG) of the semitendinosus and quadriceps vastus medialis, and stretch discomfort were recorded in six body positions during PKE. The different maximal active positions of the cervical spine (neutral; flexion; extension), thoracic spine (neutral; flexion), and ankle (neutral; dorsiflexion) were passively combined for the tests. Visual analog scale scores and EMG were unaffected by body segment positioning. An effect of the ankle joint was verified on the peak torque and knee maximum angle when the ankle was in the dorsiflexion position (P < 0.05). Upper trunk positioning had an effect on the knee submaximal torque (P < 0.05), observed as an increase in the knee passive submaximal torque when the cervical and thoracic spines were flexed (P < 0.05). In conclusion, other apparently mechanical unrelated body segments influence torque-angle response since different positions of head, upper trunk, and foot induce dissimilar knee mechanical responses during passive extension. © 2014 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Design and characterization of a biologically inspired quasi-passive prosthetic ankle-foot.

PubMed

Mooney, Luke M; Lai, Cara H; Rouse, Elliott J

2014-01-01

By design, commonly worn energy storage and release (ESR) prosthetic feet cannot provide biologically realistic ankle joint torque and angle profiles during walking. Additionally, their anthropomorphic, cantilever architecture causes their mechanical stiffness to decrease throughout the stance phase of walking, opposing the known trend of the biological ankle. In this study, the design of a quasi-passive pneumatic ankle-foot prosthesis is detailed that is able to replicate the biological ankle's torque and angle profiles during walking. The prosthetic ankle is comprised of a pneumatic piston, bending spring and solenoid valve. The mechanical properties of the pneumatic ankle prosthesis are characterized using a materials testing machine and the properties are compared to those from a common, passive ESR prosthetic foot. The characterization spanned a range of ankle equilibrium pressures and testing locations beneath the foot, analogous to the location of center of pressure within the stance phase of walking. The pneumatic ankle prosthesis was shown to provide biologically appropriate trends and magnitudes of torque, angle and stiffness behavior, when compared to the passive ESR prosthetic foot. Future work will focus on the development of a control system for the quasi-passive device and clinical testing of the pneumatic ankle to demonstrate efficacy.

Influence of Prosthetic Screw Material on Joint Stability in Passive and Non-Passive Implant-Supported Dentures

PubMed Central

Spazzin, Aloísio Oro; Henriques, Guilherme Elias Pessanha; de Arruda Nóbilo, Mauro Antônio; Consani, Rafael Leonardo Xediek; Correr-Sobrinho, Lourenço; Mesquita, Marcelo Ferraz

2009-01-01

Objectives: This study evaluated the influence of prosthetic screw material on joint stability in implantsupported dentures at two levels of fit. Methods: Ten mandibular implant-supported dentures were fabricated. Twenty cast models were fabricated using these dentures. Four groups (n=10) were tested, according to the vertical fit of the dentures [passive and non-passive] and prosthetic screw materials [titanium (Ti) or gold (Au) alloy]. The one-screw test was performed to quantify the vertical misfits using an optic microscope. The loosening torque for the prosthetic screws was measured 24 hours after the tightening torque (10 Ncm) using a digital torque meter. Data were analyzed by two-way ANOVA and Tukey’s test (α=0.05). Results: Overall, dentures with passive fit and Ti screws resulted in significantly higher loosening torque of the prosthetic screws (p<0.05). No significant interaction was found between fit level and screw material (p=0.199). The prosthetic screw material and fit of implant-supported dentures have an influence on screw joint stability. Ti screws presented higher joint stability than Au screws and minimum of misfit should be found clinically to improve the mechanical behavior of the screw joint. PMID:20148135

Wetland-based passive treatment systems for gold ore processing effluents containing residual cyanide, metals and nitrogen species.

PubMed

Alvarez, R; Ordóñez, A; Loredo, J; Younger, P L

2013-10-01

Gold extraction operations generate a variety of wastes requiring responsible disposal in compliance with current environmental regulations. During recent decades, increased emphasis has been placed on effluent control and treatment, in order to avoid the threat to the environment posed by toxic constituents. In many modern gold mining and ore processing operations, cyanide species are of most immediate concern. Given that natural degradation processes are known to reduce the toxicity of cyanide over time, trials have been made at laboratory and field scales into the feasibility of using wetland-based passive systems as low-cost and environmentally friendly methods for long-term treatment of leachates from closed gold mine tailing disposal facilities. Laboratory experiments on discrete aerobic and anaerobic treatment units supported the development of design parameters for the construction of a field-scale passive system at a gold mine site in northern Spain. An in situ pilot-scale wetland treatment system was designed, constructed and monitored over a nine-month period. Overall, the results suggest that compost-based constructed wetlands are capable of detoxifying cyanidation effluents, removing about 21.6% of dissolved cyanide and 98% of Cu, as well as nitrite and nitrate. Wetland-based passive systems can therefore be considered as a viable technology for removal of residual concentrations of cyanide from leachates emanating from closed gold mine tailing disposal facilities.

Stimulus conflict triggers behavioral avoidance.

PubMed

Dignath, David; Eder, Andreas B

2015-12-01

According to a recent extension of the conflict-monitoring theory, conflict between two competing response tendencies is registered as an aversive event and triggers a motivation to avoid the source of conflict. In the present study, we tested this assumption. Over five experiments, we examined whether conflict is associated with an avoidance motivation and whether stimulus conflict or response conflict triggers an avoidance tendency. Participants first performed a color Stroop task. In a subsequent motivation test, participants responded to Stroop stimuli with approach- and avoidance-related lever movements. These results showed that Stroop-conflict stimuli increased the frequency of avoidance responses in a free-choice motivation test, and also increased the speed of avoidance relative to approach responses in a forced-choice test. High and low proportions of response conflict in the Stroop task had no effect on avoidance in the motivation test. Avoidance of conflict was, however, obtained even with new conflict stimuli that had not been presented before in a Stroop task, and when the Stroop task was replaced with an unrelated filler task. Taken together, these results suggest that stimulus conflict is sufficient to trigger avoidance.

Parsing the Passive: Comparing Children with Specific Language Impairment to Sequential Bilingual Children

ERIC Educational Resources Information Center

Marinis, Theodoros; Saddy, Douglas

2013-01-01

Twenty-five monolingual (L1) children with specific language impairment (SLI), 32 sequential bilingual (L2) children, and 29 L1 controls completed the Test of Active & Passive Sentences-Revised (van der Lely 1996) and the Self-Paced Listening Task with Picture Verification for actives and passives (Marinis 2007). These revealed important…

Passivation of MBE grown InGaSb/InAs superlattice photodiodes

NASA Technical Reports Server (NTRS)

Hill, Cory J.; Keo, Sam S.; Mumolo, Jason M.; Gunapala, Sarath D.

2005-01-01

We have performed wet chemical passivation tests on InGaSb/InAs superlattice photodiode structures grown molecular beam epitaxy. The details of the devices growth and characterization as well as the results of chemical passivation involving RuCl3 and H2SO4 with SiO2 dielectric depositions are presented.

Passively Shunted Piezoelectric Damping of Centrifugally-Loaded Plates

NASA Technical Reports Server (NTRS)

Duffy, Kirsten P.; Provenza, Andrew J.; Trudell, Jeffrey J.; Min, James B.

2009-01-01

Researchers at NASA Glenn Research Center have been investigating shunted piezoelectric circuits as potential damping treatments for turbomachinery rotor blades. This effort seeks to determine the effects of centrifugal loading on passively-shunted piezoelectric - damped plates. Passive shunt circuit parameters are optimized for the plate's third bending mode. Tests are performed both non-spinning and in the Dynamic Spin Facility to verify the analysis, and to determine the effectiveness of the damping under centrifugal loading. Results show that a resistive shunt circuit will reduce resonant vibration for this configuration. However, a tuned shunt circuit will be required to achieve the desired damping level. The analysis and testing address several issues with passive shunt circuit implementation in a rotating system, including piezoelectric material integrity under centrifugal loading, shunt circuit implementation, and tip mode damping.

Facilitation by 8-OH-DPAT of passive avoidance performance in rats after inactivation of 5-HT1A receptors

PubMed Central

Otano, Ana; García-Osta, Ana; Ballaz, Santiago; Frechilla, Diana; Del Río, Joaquín

1999-01-01

Pretraining administration of 8-hydroxy-2-di-n-propylamino-tetralin (8-OH-DPAT 0.1 mg kg−1), a 5-HT1A receptor agonist, or buspirone (1 mg kg−1), a 5-HT1A receptor partial agonist, markedly impaired passive avoidance retention in rats 24 h later. The effect of 8-OH-DPAT was prevented by the 5-HT1A receptor antagonists, NAN-190 and WAY-100635, at doses without any intrinsic effect.N-ethoxycarbonyl-2-ethoxy-1,2-dihydroquinoline (EEDQ 10 mg kg−1), an alkylating agent that inactivates different G-protein coupled receptors, impaired retention performance when given 48 h pretraining. The disruptive effect of EEDQ was reversed by 8-OH-DPAT or buspirone, given 30 min before training.Non-specific actions did not account for 8-OH-DPAT-induced reversal of the EEDQ effect since no significant difference in locomotor activity or in pain threshold was found between rats receiving EEDQ or EEDQ+8-OH-DPAT.When NAN-190 (1 mg kg−1) or WAY-100635 (0.5 mg kg−1) were given before 8-OH-DPAT to EEDQ-pretreated animals, the reversal by 8-OH-DPAT of EEDQ-induced retention impairment was still more pronounced. However, no EEDQ reversal by 8-OH-DPAT was found when 5-HT1A receptors were protected by WAY-100635 (10 mg kg−1) 30 min before EEDQ.In the hippocampus of EEDQ-treated rats, 5-HT7 receptors were less inactivated than 5-HT1A receptors and significant increases were found in 5-HT1A but not in 5-HT7 receptor mRNA levels. Ritanserin and methiothepin (10 mg kg−1 each), antagonists with higher affinity at 5-HT7 than at 5-HT1A receptors, prevented the retention impairment induced by EEDQ but did not significantly protect against 5-HT7 receptor inactivation.The results indicate that the facilitatory effect of 8-OH-DPAT is not mediated through 5-HT1A receptors and suggest that other 8-OH-DPAT-sensitive receptors could be involved in the dual effect of 8-OH-DPAT on passive avoidance performance in rats. PMID:10588924

Non-invasive assessment of hemispheric language dominance by optical topography during a brief passive listening test: a pilot study.

PubMed

Bembich, Stefano; Demarini, Sergio; Clarici, Andrea; Massaccesi, Stefano; Grasso, Domenico Loenardo

2011-12-01

The Wada test is usually used for pre-surgical assessment of language lateralization. Considering its invasiveness and risk of complications, alternative methods have been proposed but they are not always applicable to non-cooperative patients. In this study we explored the possibility of using optical topography (OT)--a multichannel near-infrared system--for non-invasive assessment of hemispheric language dominance during passive listening. Cortical activity was monitored in a sample of healthy, adult Italian native speakers, all right-handed. We assessed changes in oxy-haemoglobin concentration in temporal, parietal and posterior frontal lobes during a passive listening of bi-syllabic words and vowel-consonant-vowel syllables lasting less then 3 minutes. Activated channels were identified by t tests. Left hemisphere showed significant activity only during the passive listening of bi-syllabic words. Specifically, the superior temporal gyrus, the supramarginal gyrus and the posterior inferior parietal lobe were activated. During passive listening of bi-syllabic words, right handed healthy adults showed a significant activation in areas already known to be involved in speech comprehension. Although more research is needed, OT proved to be a promising alternative to the Wada test for non-invasive assessment of hemispheric language lateralization, even if using a particularly brief trial, which has been designed for future applications with non-cooperative subjects.

Assessment of passive knee stiffness and viscosity in individuals with spinal cord injury using pendulum test.

PubMed

Joghtaei, Mahmoud; Arab, Amir Massoud; Hashemi-Nasl, Hamed; Joghataei, Mohammad Taghi; Tokhi, Mohammad Osman

2015-03-01

Stiffness and viscosity represent passive resistances to joint motion related with the structural properties of the joint tissue and of the musculotendinous complex. Both parameters can be affected in patients with spinal cord injury (SCI). The purpose of this study was to measure passive knee stiffness and viscosity in patients with SCI with paraplegia and healthy subjects using Wartenberg pendulum test. Non-experimental, cross-sectional, case-control design. An outpatient physical therapy clinic, University of social welfare and Rehabilitation Science, Iran. A sample of convenience sample of 30 subjects participated in the study. Subjects were categorized into two groups: individuals with paraplegic SCI (n = 15, age: 34.60 ± 9.18 years) and 15 able-bodied individuals as control group (n = 15, age: 30.66 ± 11.13 years). Not applicable. Passive pendulum test of Wartenberg was used to measure passive viscous-elastic parameters of the knee (stiffness, viscosity) in all subjects. Statistical analysis (independent t-test) revealed significant difference in the joint stiffness between healthy subjects and those with paraplegic SCI (P = 0.01). However, no significant difference was found in the viscosity between two groups (P = 0.17). Except for first peak flexion angle, all other displacement kinematic parameters exhibited no statistically significant difference between normal subjects and subjects with SCI. Patients with SCI have significantly greater joint stiffness compared to able-bodied subjects.

Evaluation of an image-based tracking workflow using a passive marker and resonant micro-coil fiducials for automatic image plane alignment in interventional MRI.

PubMed

Neumann, M; Breton, E; Cuvillon, L; Pan, L; Lorenz, C H; de Mathelin, M

2012-01-01

In this paper, an original workflow is presented for MR image plane alignment based on tracking in real-time MR images. A test device consisting of two resonant micro-coils and a passive marker is proposed for detection using image-based algorithms. Micro-coils allow for automated initialization of the object detection in dedicated low flip angle projection images; then the passive marker is tracked in clinical real-time MR images, with alternation between two oblique orthogonal image planes along the test device axis; in case the passive marker is lost in real-time images, the workflow is reinitialized. The proposed workflow was designed to minimize dedicated acquisition time to a single dedicated acquisition in the ideal case (no reinitialization required). First experiments have shown promising results for test-device tracking precision, with a mean position error of 0.79 mm and a mean orientation error of 0.24°.

Novel Concrete Temperature Monitoring Method Based on an Embedded Passive RFID Sensor Tag.

PubMed

Liu, Yongsheng; Deng, Fangming; He, Yigang; Li, Bing; Liang, Zhen; Zhou, Shuangxi

2017-06-22

This paper firstly introduces the importance of temperature control in concrete measurement, then a passive radio frequency identification (RFID) sensor tag embedded for concrete temperature monitoring is presented. In order to reduce the influences of concrete electromagnetic parameters during the drying process, a T-type antenna is proposed to measure the concrete temperature at the required depth. The proposed RFID sensor tag is based on the EPC generation-2 ultra-high frequency (UHF) communication protocol and operates in passive mode. The temperature sensor can convert the sensor signals to corresponding digital signals without an external reference clock due to the adoption of phase-locked loop (PLL)-based architecture. Laboratory experimentation and on-site testing demonstrate that our sensor tag embedded in concrete can provide reliable communication performance in passive mode. The maximum communicating distance between reader and tag is 7 m at the operating frequency of 915 MHz and the tested results show high consistency with the results tested by a thermocouple.

Novel Concrete Temperature Monitoring Method Based on an Embedded Passive RFID Sensor Tag

PubMed Central

Liu, Yongsheng; Deng, Fangming; He, Yigang; Li, Bing; Liang, Zhen; Zhou, Shuangxi

2017-01-01

This paper firstly introduces the importance of temperature control in concrete measurement, then a passive radio frequency identification (RFID) sensor tag embedded for concrete temperature monitoring is presented. In order to reduce the influences of concrete electromagnetic parameters during the drying process, a T-type antenna is proposed to measure the concrete temperature at the required depth. The proposed RFID sensor tag is based on the EPC generation-2 ultra-high frequency (UHF) communication protocol and operates in passive mode. The temperature sensor can convert the sensor signals to corresponding digital signals without an external reference clock due to the adoption of phase-locked loop (PLL)-based architecture. Laboratory experimentation and on-site testing demonstrate that our sensor tag embedded in concrete can provide reliable communication performance in passive mode. The maximum communicating distance between reader and tag is 7 m at the operating frequency of 915 MHz and the tested results show high consistency with the results tested by a thermocouple. PMID:28640188

A Review of International Space Station Habitable Element Equipment Offgassing Characteristics

NASA Technical Reports Server (NTRS)

Perry, Jay L.

2010-01-01

Crewed spacecraft trace contaminant control employs both passive and active methods to achieve acceptable cabin atmospheric quality. Passive methods include carefully selecting materials of construction, employing clean manufacturing practices, and minimizing systems and payload operational impacts to the cabin environment. Materials selection and manufacturing processes constitute the first level of equipment offgassing control. An element-level equipment offgassing test provides preflight verification that passive controls have been successful. Offgassing test results from multiple International Space Station (ISS) habitable elements and cargo vehicles are summarized and implications for active contamination control equipment design are discussed

Clinical outcome of calves with failure of passive transfer as diagnosed by a commercially available IgG quick test kit

PubMed Central

Stilwell, George; Carvalho, Rita C.

2011-01-01

The efficacy of an IgG quick test in detecting calves with failure of passive transfer was assessed. The test was carried out on 97 male calves, 38% of which were negative (IgG < 10 mg/mL). Morbidity and mortality due to infectious diseases were significantly higher in the negative group showing that the quick test is useful in identifying calves more susceptible to infectious disease. PMID:22043074

Multisample cross-validation of a model of childhood posttraumatic stress disorder symptomatology.

PubMed

Anthony, Jason L; Lonigan, Christopher J; Vernberg, Eric M; Greca, Annette M La; Silverman, Wendy K; Prinstein, Mitchell J

2005-12-01

This study is the latest advancement of our research aimed at best characterizing children's posttraumatic stress reactions. In a previous study, we compared existing nosologic and empirical models of PTSD dimensionality and determined the superior model was a hierarchical one with three symptom clusters (Intrusion/Active Avoidance, Numbing/Passive Avoidance, and Arousal; Anthony, Lonigan, & Hecht, 1999). In this study, we cross-validate this model in two populations. Participants were 396 fifth graders who were exposed to either Hurricane Andrew or Hurricane Hugo. Multisample confirmatory factor analysis demonstrated the model's factorial invariance across populations who experienced traumatic events that differed in severity. These results show the model's robustness to characterize children's posttraumatic stress reactions. Implications for diagnosis, classification criteria, and an empirically supported theory of PTSD are discussed.

Transfer of Training and Processing Instruction: From Input to Output

ERIC Educational Resources Information Center

VanPatten, Bill; Uludag, Onur

2011-01-01

In this paper we report the findings of an experiment to test whether training via processing instruction transfers to output tasks. Two groups of Turkish L1-English L2 learners participated: one that received processing instruction on passive structures and a control group that did not receive any instruction on passives. A pre-test/multiple…

Symptom profile of multiple chemical sensitivity in actual life.

PubMed

Saito, Mariko; Kumano, Hiroaki; Yoshiuchi, Kazuhiro; Kokubo, Naomi; Ohashi, Kyoko; Yamamoto, Yoshiharu; Shinohara, Naohide; Yanagisawa, Yukio; Sakabe, Kou; Miyata, Mikio; Ishikawa, Satoshi; Kuboki, Tomifusa

2005-01-01

This study was conducted to confirm the definition of multiple chemical sensitivity (MCS) in actual life: that multiple symptoms are provoked in multiple organs by exposure to, and ameliorated by avoidance of, multiple chemicals at low levels. We used the Ecological Momentary Assessment to monitor everyday symptoms and the active sampling and passive sampling methods to measure environmental chemical exposure. Eighteen patients with MCS, diagnosed according to the 1999 consensus criteria, and 12 healthy controls participated in this study. Fourteen patients and 12 controls underwent 1-week measurement of physical and psychologic symptoms and of the levels of exposure to various chemicals. Linear mixed models were used to test the hypotheses regarding the symptom profile of MCS patients. Some causative chemicals were detected in 11 of 14 MCS patients. Two other patients did not report any hypersensitivity episodes, whereas passive sampling showed far less exposure to chemicals than control subjects. Another subject reported episodic symptoms but was excluded from the following analyses because no possible chemical was detected. Eleven of the 17 physical symptoms and all four mood subscales examined were significantly aggravated in the interview based on "patient-initiated symptom prompts." On the other hand, there were no differences in physical symptoms or mood subscales between MCS patients and control subjects in the interview based on "random prompts." MCS patients do not have either somatic or psychologic symptoms under chemical-free conditions, and symptoms may be provoked only when exposed to chemicals.

Ecotoxicity of wastes in avoidance tests with Enchytraeus albidus, Enchytraeus crypticus and Eisenia fetida (Oligochaeta).

PubMed

Kobeticová, Klára; Hofman, Jakub; Holoubek, Ivan

2010-04-01

Contact bioassays are important for testing the ecotoxicity of solid materials. However, survival and reproduction tests are often not practical due to their duration which may last for several weeks. Avoidance tests with soil invertebrates may offer an alternative or extension to the classic test batteries due to their short duration (days rather than weeks) and due to a sensitive sub-acute endpoint (behavior). (a) to evaluate the effects of three solid industrial wastes (incineration ash, contaminated wood chips and contaminated soil) on three Oligochaeta species (enchytraeids Enchytraeusalbidus, Enchytraeus crypticus and earthworm Eisenia fetida) in avoidance tests; (b) to compare the sensitivity among the species and to compare results of avoidance test to reproduction tests; (c) to elucidate if measuring the weight in the earthworm avoidance test could be reasonable additional endpoint. Avoidance mostly increased with the increasing percent of waste in the mixture showing a dose-response curve. E. fetida was the most sensitive species and E. crypticus the least one. An additional endpoint, (changes in weight after two-day exposure) was not found to be more sensitive than avoidance reaction, but it confirmed that earthworms staying in the highest concentrations of the waste mixture were affected showing apparent weight reduction. Our results indicate that avoidance tests with earthworms and enchytraeids are feasible for waste testing. Copyright 2009 Elsevier Ltd. All rights reserved.

An examination of the roles of glutamate and sex in latent inhibition: Relevance to the glutamate hypothesis of schizophrenia?

PubMed

Huang, Andrew Chih Wei; Bo-Han He, Alan; Chen, Chih-Chung

2017-10-01

The present study examined the effects of the glutamate receptor antagonist MK-801, the glutamate receptor agonist N-methyl-D-aspartate (NMDA), and sexual dimorphism on latent inhibition to elucidate the glutamate hypothesis of schizophrenia. During the pre-exposure phase, 56 male and 65 female Wistar rats were intracerebroventricularly administered normal saline, MK-801 or NMDA, in the left ventricle and then exposed to a passive avoidance box (or a different context) in three trials over 3 days. Then, all of the rats were placed in the light compartment of the passive avoidance box and were allowed to enter the dark compartment, where they each received a footshock (1mA, 2s) in five trials over 5 days. Injections of the glutamate drugs NMDA and MK-801 did not affect latent inhibition. Sexual dimorphism did not occur in latent inhibition. The present data on the male rats indicated that the glutamate system did not affect latent inhibition, indicating that the glutamate system was not like the dopamine system in terms of mediating the positive symptoms of schizophrenia. The glutamate system might be involved in the negative and cognitive symptoms of schizophrenia. The results may provide information for novel treatments of the negative and cognitive symptoms of schizophrenia. Copyright © 2017 Elsevier B.V. All rights reserved.

Operation in low edge safety factor regime and passive disruption avoidance due to stellarator rotational transform in the Compact Toroidal Hybrid

NASA Astrophysics Data System (ADS)

Pandya, M. D.; Ennis, D. A.; Hartwell, G. J.; Maurer, D. A.

2015-11-01

Low edge safety factor operation at a value less than two (q (a) = 1 /ttot (a) < 2) is routine on the Compact Toroidal Hybrid device. Presently, the operational space of this current carrying stellarator extends down to q (a) = 1 . 2 without significant n = 1 kink mode activity after the initial plasma current rise of the discharge. The disruption dynamics of these low q (a) plasmas depend upon the fraction of rotational transform produced by external stellarator coils to that generated by the plasma current. We observe that when about 10% of the total rotational transform is supplied by the stellarator coils, low q (a) disruptions are passively suppressed and avoided even though q (a) < 2 . When the plasma does disrupt, the instability precursors measured and implicated as the cause are internal tearing modes with poloidal, m, and toroidal, n, mode numbers of m / n = 3 / 2 and 4 / 3 observed by external magnetic sensors, and m / n = 1 / 1 activity observed by core soft x-ray emissivity measurements. Even though q (a) passes through and becomes much less than two, external n = 1 kink mode activity does not appear to play a significant role in the observed disruption phenomenology. This work is supported by US Department of Energy Grant No. DE-FG02-00ER54610.

Low edge safety factor operation and passive disruption avoidance in current carrying plasmas by the addition of stellarator rotational transform

NASA Astrophysics Data System (ADS)

Pandya, M. D.; ArchMiller, M. C.; Cianciosa, M. R.; Ennis, D. A.; Hanson, J. D.; Hartwell, G. J.; Hebert, J. D.; Herfindal, J. L.; Knowlton, S. F.; Ma, X.; Massidda, S.; Maurer, D. A.; Roberds, N. A.; Traverso, P. J.

2015-11-01

Low edge safety factor operation at a value less than two ( q (a )=1 /ι̷tot(a )<2 ) is routine on the Compact Toroidal Hybrid device with the addition of sufficient external rotational transform. Presently, the operational space of this current carrying stellarator extends down to q (a )=1.2 without significant n = 1 kink mode activity after the initial plasma current rise phase of the discharge. The disruption dynamics of these low edge safety factor plasmas depend upon the fraction of helical field rotational transform from external stellarator coils to that generated by the plasma current. We observe that with approximately 10% of the total rotational transform supplied by the stellarator coils, low edge q disruptions are passively suppressed and avoided even though q(a) < 2. When the plasma does disrupt, the instability precursors measured and implicated as the cause are internal tearing modes with poloidal, m, and toroidal, n, helical mode numbers of m /n =3 /2 and 4/3 observed on external magnetic sensors and m /n =1 /1 activity observed on core soft x-ray emissivity measurements. Even though the edge safety factor passes through and becomes much less than q(a) < 2, external n = 1 kink mode activity does not appear to play a significant role in the disruption phenomenology observed.

Impact of leadership styles adopted by head nurses on job satisfaction: a comparative study between governmental and private hospitals in Jordan.

PubMed

Abdelhafiz, Ibrahim Mbarak; Alloubani, Aladeen Mah'D; Almatari, Mohammad

2016-04-01

Previous studies demonstrated that leadership styles are the basis of daily interactions between leaders and employees and facilitate and enhance work processes. This study aimed to explore how the leadership styles of nurse leaders affect job satisfaction among working nurses. Quantitative, descriptive and comparative methods were used. Three main Ministry of Health hospitals in different areas of Jordan and three private hospitals in Amman were selected. Among the leadership styles measured by the Multi-factor Leadership Questionnaire 5X, transformational leadership had been used by head nurse managers in both settings more than transactional leadership and passive-avoidant leadership. The level of job satisfaction among nursing staff was higher in public hospitals than in private hospitals in this study. A positive relationship was found between the overall score for transformational leadership and job satisfaction (r = 0.374**). The overall transactional leadership score correlated positively with job satisfaction (r = 0.391**). Conversely, the overall correlation between passive-avoidant leadership and job satisfaction was negative (r = -0.240). The increased development of transformational leadership behaviours increases nurses' job satisfaction and thus contributes to an increased retention of nurses. The ability of hospitals to address the leadership styles of head nurses and their impacts on job satisfaction will be strengthened. © 2015 John Wiley & Sons Ltd.

Prediction Error Representation in Individuals with Generalized Anxiety Disorder During Passive Avoidance

PubMed Central

White, Stuart F.; Geraci, Marilla; Lewis, Elizabeth; Leshin, Joseph; Teng, Cindy; Averbeck, Bruno; Meffert, Harma; Ernst, Monique; Blair, James R.; Grillon, Christian; Blair, Karina S.

2017-01-01

Objective Deficits in reinforcement-based decision-making have been reported in Generalized Anxiety Disorder. However, the pathophysiology of these deficits is largely unknown, extant studies have mainly examined youth and the integrity of core functional processes underpinning decision-making remain undetermined. In particular, it is unclear whether the representation of reinforcement prediction error (PE: the difference between received and expected reinforcement) is disrupted in Generalized Anxiety Disorder. The current study addresses these issues in adults with the disorder. Methods Forty-six un-medicated individuals with Generalized Anxiety Disorder and 32 healthy controls group-matched on IQ, gender and age, completed a passive avoidance task while undergoing functional MRI. Results Behaviorally, individuals with Generalized Anxiety Disorder showed impaired reinforcement-based decision-making. Imaging results revealed that during feedback, individuals with Generalized Anxiety Disorder relative to healthy controls showed a reduced correlation between PE and activity within ventromedial prefrontal cortex, ventral striatum and other structures implicated in decision-making. In addition, individuals with Generalized Anxiety Disorder relative to healthy participants showed a reduced correlation between punishment, but not reward, PEs and activity within bilateral lentiform nucleus/putamen. Conclusions This is the first study to identify computational impairments during decision-making in Generalized Anxiety Disorder. PE signaling is significantly disrupted in individuals with the disorder and may underpin the decision-making deficits observed in patients with GAD. PMID:27631963

Test case specifications for coupled neutronics-thermal hydraulics calculation of Gas-cooled Fast Reactor

NASA Astrophysics Data System (ADS)

Osuský, F.; Bahdanovich, R.; Farkas, G.; Haščík, J.; Tikhomirov, G. V.

2017-01-01

The paper is focused on development of the coupled neutronics-thermal hydraulics model for the Gas-cooled Fast Reactor. It is necessary to carefully investigate coupled calculations of new concepts to avoid recriticality scenarios, as it is not possible to ensure sub-critical state for a fast reactor core under core disruptive accident conditions. Above mentioned calculations are also very suitable for development of new passive or inherent safety systems that can mitigate the occurrence of the recriticality scenarios. In the paper, the most promising fuel material compositions together with a geometry model are described for the Gas-cooled fast reactor. Seven fuel pin and fuel assembly geometry is proposed as a test case for coupled calculation with three different enrichments of fissile material in the form of Pu-UC. The reflective boundary condition is used in radial directions of the test case and vacuum boundary condition is used in axial directions. During these condition, the nuclear system is in super-critical state and to achieve a stable state (which is numerical representation of operational conditions) it is necessary to decrease the reactivity of the system. The iteration scheme is proposed, where SCALE code system is used for collapsing of a macroscopic cross-section into few group representation as input for coupled code NESTLE.

Comparing the impact of chronic energy restriction and vitamin E supplementation on the behavior of adult rats.

PubMed

Diniz, Derlange B; de Oliveira, Suzana L; Melo, Liana L; Amaya-Farfan, Jaime

2009-09-01

The purpose of this work was to investigate the influence of energy restriction and vitamin E supplementation on memory, learning, anxiety and spontaneous locomotion in adult rats. Three-month-old male Wistar rats were grouped according to diet: Control (AIN 93-M; n=18), Supplemented (AIN 93-M + 1425 IU all-rac-alpha-tocopheryl acetate/kg diet; n=22) and Restricted (AIN 93-M with 30% reduction in carbohydrate energy; n=23). Sixteen weeks after, the passive avoidance (PA), elevated plus-maze (EPM) and open field (OF) tests were applied. In the EPM test, the behavioral profile of the supplemented group was characterized by a lower frequency of entries into the open arms (P < 0,026), whereas the restricted group showed a lower frequency of head dipping (P < 0,003). The ratio between the time span of the shocks and the number of attempts were larger for the supplemented than for the non-supplemented animals (P = 0,0474), thus suggesting a delay in learning in the PA test. Taken together, these results suggest that a long-term combination of carbohydrate energy restriction in rats should not cause negative behavioral alterations. Compared with vitamin E supplementation, the restricted diet performed equally or better in rats as an alternate antioxidant diet.

Extract from Fructus cannabis activating calcineurin improved learning and memory in mice with chemical drug-induced dysmnesia.

PubMed

Luo, Jing; Yin, Jiang-Hua; Wu, He-Zhen; Wei, Qun

2003-11-01

To investigate the effects of extract from Fructus cannabis (EFC) that can activate calcineurin on learning and memory impairment induced by chemical drugs in mice. Bovine brain calcineurin and calmodulin were isolated from frozen tissues. The activity of calcineurin was assayed using p-nitrophenyl phosphate (PNPP) as the substrate. Step-down type passive avoidance test and water maze were used together to determine the effects of EFC on learning and memory dysfunction. EFC activated calcineurin activity at a concentration range of 0.01-100 g/L. The maximal value of EFC on calcineurin activity (35 %+/-5 %) appeared at a concentration of 10 g/L. The chemical drugs such as scopolamine, sodium nitrite, and 45 % ethanol, and sodium pentobarbital induced learning and memory dysfunction. EFC administration (0.2, 0.4, and 0.8 g/kg, igx7 d) prolonged the latency and decreased the number of errors in the step-down test. EFC, given for 7 d, enhanced the spatial resolution of amnesic mice in water maze test. EFC overcome amnesia of three stages of memory process at the dose of 0.2 g/kg. EFC with an activation role of calcineurin can improve the impaired learning and memory induced by chemical drugs in mice.

Evaluation of the antipsychotic potential of Panax quinquefolium in ketamine induced experimental psychosis model in mice.

PubMed

Chatterjee, Manavi; Singh, Seema; Kumari, Reena; Verma, Anil Kumar; Palit, Gautam

2012-04-01

The search for novel pharmacotherapy from medicinal plants for psychiatric illnesses has progressed significantly from the past few decades and their therapeutic potential has been assessed in a variety of animal models. The aim of our study was to screen one such plant, Panax quinquefolium (PQ), with significant neuroactive properties for its antipsychotic potential. A graded dose study with PQ at 12.5-200 mg/kg, p. o. showed differential effects against the ketamine induced hyperactivity in the Digiscan animal activity monitor. Nevertheless at 100 mg/kg, p.o., PQ blocked ketamine induced memory impairment in the passive avoidance paradigm. In the chronic studies, PQ reduced the ketamine induced enhanced immobility in the forced swim test and did not show extra-pyramidal side effects in bar test and wood block test of catalepsy. These behavioural effects were compared with standard drugs haloperidol and clozapine. Further PQ reduced DA and 5-HT content after chronic treatment, but not after acute administration. In addition, PQ extract reduced acetylcholinesterase activity and nitrate levels, however increased glutamate levels in hippocampus. Overall our findings suggest that PQ possess antipsychotic like properties, which may leads to future studies with its specific constituents which may particularly be beneficial in predominant negative and cognitive symptoms of schizophrenia.

Turbulent flow separation control through passive techniques

NASA Technical Reports Server (NTRS)

Lin, J. C.; Howard, F. G.; Selby, G. V.

1989-01-01

Several passive separation control techniques for controlling moderate two-dimensional turbulent flow separation over a backward-facing ramp are studied. Small transverse and swept grooves, passive porous surfaces, large longitudinal grooves, and vortex generators were among the techniques used. It was found that, unlike the transverse and longitudinal grooves of an equivalent size, the 45-deg swept-groove configurations tested tended to enhance separation.

Hybrid Active/Passive Jet Engine Noise Suppression System

NASA Technical Reports Server (NTRS)

Parente, C. A.; Arcas, N.; Walker, B. E.; Hersh, A. S.; Rice, E. J.

1999-01-01

A novel adaptive segmented liner concept has been developed that employs active control elements to modify the in-duct sound field to enhance the tone-suppressing performance of passive liner elements. This could potentially allow engine designs that inherently produce more tone noise but less broadband noise, or could allow passive liner designs to more optimally address high frequency broadband noise. A proof-of-concept validation program was undertaken, consisting of the development of an adaptive segmented liner that would maximize attenuation of two radial modes in a circular or annular duct. The liner consisted of a leading active segment with dual annuli of axially spaced active Helmholtz resonators, followed by an optimized passive liner and then an array of sensing microphones. Three successively complex versions of the adaptive liner were constructed and their performances tested relative to the performance of optimized uniform passive and segmented passive liners. The salient results of the tests were: The adaptive segmented liner performed well in a high flow speed model fan inlet environment, was successfully scaled to a high sound frequency and successfully attenuated three radial modes using sensor and active resonator arrays that were designed for a two mode, lower frequency environment.

Protective capping and surface passivation of III-V nanowires by atomic layer deposition

DOE Office of Scientific and Technical Information (OSTI.GOV)

Dhaka, Veer, E-mail: veer.dhaka@aalto.fi; Perros, Alexander; Kakko, Joona-Pekko

2016-01-15

Low temperature (∼200 °C) grown atomic layer deposition (ALD) films of AlN, TiN, Al{sub 2}O{sub 3}, GaN, and TiO{sub 2} were tested for protective capping and surface passivation of bottom-up grown III-V (GaAs and InP) nanowires (NWs), and top-down fabricated InP nanopillars. For as-grown GaAs NWs, only the AlN material passivated the GaAs surface as measured by photoluminescence (PL) at low temperatures (15K), and the best passivation was achieved with a few monolayer thick (2Å) film. For InP NWs, the best passivation (∼2x enhancement in room-temperature PL) was achieved with a capping of 2nm thick Al{sub 2}O{sub 3}. All othermore » ALD capping layers resulted in a de-passivation effect and possible damage to the InP surface. Top-down fabricated InP nanopillars show similar passivation effects as InP NWs. In particular, capping with a 2 nm thick Al{sub 2}O{sub 3} layer increased the carrier decay time from 251 ps (as-etched nanopillars) to about 525 ps. Tests after six months ageing reveal that the capped nanostructures retain their optical properties. Overall, capping of GaAs and InP NWs with high-k dielectrics AlN and Al{sub 2}O{sub 3} provides moderate surface passivation as well as long term protection from oxidation and environmental attack.« less

Motion correction for passive radiation imaging of small vessels in ship-to-ship inspections

NASA Astrophysics Data System (ADS)

Ziock, K. P.; Boehnen, C. B.; Ernst, J. M.; Fabris, L.; Hayward, J. P.; Karnowski, T. P.; Paquit, V. C.; Patlolla, D. R.; Trombino, D. G.

2016-01-01

Passive radiation detection remains one of the most acceptable means of ascertaining the presence of illicit nuclear materials. In maritime applications it is most effective against small to moderately sized vessels, where attenuation in the target vessel is of less concern. Unfortunately, imaging methods that can remove source confusion, localize a source, and avoid other systematic detection issues cannot be easily applied in ship-to-ship inspections because relative motion of the vessels blurs the results over many pixels, significantly reducing system sensitivity. This is particularly true for the smaller watercraft, where passive inspections are most valuable. We have developed a combined gamma-ray, stereo visible-light imaging system that addresses this problem. Data from the stereo imager are used to track the relative location and orientation of the target vessel in the field of view of a coded-aperture gamma-ray imager. Using this information, short-exposure gamma-ray images are projected onto the target vessel using simple tomographic back-projection techniques, revealing the location of any sources within the target. The complex autonomous tracking and image reconstruction system runs in real time on a 48-core workstation that deploys with the system.

Does the diurnal increase in central temperature interact with pre-cooling or passive warm-up of the leg?

PubMed

Racinais, Sébastien; Blonc, Stephen; Oksa, Juha; Hue, Olivier

2009-01-01

Seven male subjects volunteered to participate in an investigation of whether the diurnal increase in core temperature influences the effects of pre-cooling or passive warm-up on muscular power. Morning (07:00-09:00h) and afternoon (17:00-19:00h) evaluation of maximal power output during a cycling sprint was performed on different days in a control condition (room at 21.8 degrees C, 69% rh), after 30min of pre-cooling in a cold bath (16 degrees C), or after 30min of passive warm-up in a hot bath (38 degrees C). Despite an equivalent increase from morning to afternoon in core temperature in all conditions (+0.4 degrees C, P<0.05), power output displayed a diurnal increase in control condition only. A local cooling or heating of the leg in a neutral environment blunted the diurnal variation in muscular power. Because pre-cooling decreases muscle power, force and velocity irrespective of time-of-day, athletes should strictly avoid any cooling before a sprint exercise. In summary, diurnal variation in muscle power output seems to be more influenced by muscle rather than core temperature.

I-SCAD® standoff chemical agent detector overview

NASA Astrophysics Data System (ADS)

Popa, Mirela O.; Griffin, Matthew T.

2012-06-01

This paper presents a system-level description of the I-SCAD® Standoff Chemical Agent Detector, a passive Fourier Transform InfraRed (FTIR) based remote sensing system, for detecting chemical vapor threats. The passive infrared detection system automatically searches the 7 to 14 micron region of the surrounding atmosphere for agent vapor clouds. It is capable of operating while on the move to accomplish reconnaissance, surveillance, and contamination avoidance missions. Additionally, the system is designed to meet the needs for application on air and sea as well as ground mobile and fixed site platforms. The lightweight, passive, and fully automatic detection system scans the surrounding atmosphere for chemical warfare agent vapors. It provides on-the-move, 360-deg coverage from a variety of tactical and reconnaissance platforms at distances up to 5 km. The core of the system is a rugged Michelson interferometer with a flexure spring bearing mechanism and bi-directional data acquisition capability. The modular system design facilitates interfacing to many platforms. A Reduced Field of View (RFOV) variant includes novel modifications to the scanner subcomponent assembly optical design that gives extended performance in detection range and detection probability without sacrificing existing radiometric sensitivity performance. This paper will deliver an overview of system.

Motion correction for passive radiation imaging of small vessels in ship-to-ship inspections

DOE PAGES

Ziock, Klaus -Peter; Boehnen, Chris Bensing; Ernst, Joseph M.; ...

2015-09-05

Passive radiation detection remains one of the most acceptable means of ascertaining the presence of illicit nuclear materials. In maritime applications it is most effective against small to moderately sized vessels, where attenuation in the target vessel is of less concern. Unfortunately, imaging methods that can remove source confusion, localize a source, and avoid other systematic detection issues cannot be easily applied in ship-to-ship inspections because relative motion of the vessels blurs the results over many pixels, significantly reducing system sensitivity. This is particularly true for the smaller watercraft, where passive inspections are most valuable. We have developed a combinedmore » gamma-ray, stereo visible-light imaging system that addresses this problem. Data from the stereo imager are used to track the relative location and orientation of the target vessel in the field of view of a coded-aperture gamma-ray imager. Using this information, short-exposure gamma-ray images are projected onto the target vessel using simple tomographic back-projection techniques, revealing the location of any sources within the target. Here,the complex autonomous tracking and image reconstruction system runs in real time on a 48-core workstation that deploys with the system.« less

Comparison between active (pumped) and passive (diffusive) sampling methods for formaldehyde in pathology and histology laboratories.

PubMed

Lee, Eun Gyung; Magrm, Rana; Kusti, Mohannad; Kashon, Michael L; Guffey, Steven; Costas, Michelle M; Boykin, Carie J; Harper, Martin

2017-01-01

This study was to determine occupational exposures to formaldehyde and to compare concentrations of formaldehyde obtained by active and passive sampling methods. In one pathology and one histology laboratories, exposure measurements were collected with sets of active air samplers (Supelco LpDNPH tubes) and passive badges (ChemDisk Aldehyde Monitor 571). Sixty-six sample pairs (49 personal and 17 area) were collected and analyzed by NIOSH NMAM 2016 for active samples and OSHA Method 1007 (using the manufacturer's updated uptake rate) for passive samples. All active and passive 8-hr time-weighted average (TWA) measurements showed compliance with the OSHA permissible exposure limit (PEL-0.75 ppm) except for one passive measurement, whereas 78% for the active and 88% for the passive samples exceeded the NIOSH recommended exposure limit (REL-0.016 ppm). Overall, 73% of the passive samples showed higher concentrations than the active samples and a statistical test indicated disagreement between two methods for all data and for data without outliers. The OSHA Method cautions that passive samplers should not be used for sampling situations involving formalin solutions because of low concentration estimates in the presence of reaction products of formaldehyde and methanol (a formalin additive). However, this situation was not observed, perhaps because the formalin solutions used in these laboratories included much less methanol (3%) than those tested in the OSHA Method (up to 15%). The passive samplers in general overestimated concentrations compared to the active method, which is prudent for demonstrating compliance with an occupational exposure limit, but occasional large differences may be a result of collecting aerosolized droplets or splashes on the face of the samplers. In the situations examined in this study the passive sampler generally produces higher results than the active sampler so that a body of results from passive samplers demonstrating compliance with the OSHA PEL would be a valid conclusion. However, individual passive samples can show lower results than a paired active sampler so that a single result should be treated with caution.

A Compact Magnetic Field-Based Obstacle Detection and Avoidance System for Miniature Spherical Robots.

PubMed

Wu, Fang; Vibhute, Akash; Soh, Gim Song; Wood, Kristin L; Foong, Shaohui

2017-05-28

Due to their efficient locomotion and natural tolerance to hazardous environments, spherical robots have wide applications in security surveillance, exploration of unknown territory and emergency response. Numerous studies have been conducted on the driving mechanism, motion planning and trajectory tracking methods of spherical robots, yet very limited studies have been conducted regarding the obstacle avoidance capability of spherical robots. Most of the existing spherical robots rely on the "hit and run" technique, which has been argued to be a reasonable strategy because spherical robots have an inherent ability to recover from collisions. Without protruding components, they will not become stuck and can simply roll back after running into bstacles. However, for small scale spherical robots that contain sensitive surveillance sensors and cannot afford to utilize heavy protective shells, the absence of obstacle avoidance solutions would leave the robot at the mercy of potentially dangerous obstacles. In this paper, a compact magnetic field-based obstacle detection and avoidance system has been developed for miniature spherical robots. It utilizes a passive magnetic field so that the system is both compact and power efficient. The proposed system can detect not only the presence, but also the approaching direction of a ferromagnetic obstacle, therefore, an intelligent avoidance behavior can be generated by adapting the trajectory tracking method with the detection information. Design optimization is conducted to enhance the obstacle detection performance and detailed avoidance strategies are devised. Experimental results are also presented for validation purposes.

Boundary Layer Control for Hypersonic Airbreathing Vehicles

NASA Technical Reports Server (NTRS)

Berry, Scott A.; Nowak, Robert J.; Horvath, Thomas J.

2004-01-01

Active and passive methods for tripping hypersonic boundary layers have been examined in NASA Langley Research Center wind tunnels using a Hyper-X model. This investigation assessed several concepts for forcing transition, including passive discrete roughness elements and active mass addition (or blowing), in the 20-Inch Mach 6 Air and the 31-Inch Mach 10 Air Tunnels. Heat transfer distributions obtained via phosphor thermography, shock system details, and surface streamline patterns were measured on a 0.333-scale model of the Hyper-X forebody. The comparisons between the active and passive methods for boundary layer control were conducted at test conditions that nearly match the Hyper-X nominal Mach 7 flight test-point of an angle-of-attack of 2-deg and length Reynolds number of 5.6 million. For passive roughness, the primary parametric variation was a range of trip heights within the calculated boundary layer thickness for several trip concepts. The passive roughness study resulted in a swept ramp configuration, scaled to be roughly 0.6 of the calculated boundary layer thickness, being selected for the Mach 7 flight vehicle. For the active blowing study, the manifold pressure was systematically varied (while monitoring the mass flow) for each configuration to determine the jet penetration height, with schlieren, and transition movement, with the phosphor system, for comparison to the passive results. All the blowing concepts tested, which included various rows of sonic orifices (holes), two- and three-dimensional slots, and random porosity, provided transition onset near the trip location with manifold stagnation pressures on the order of 40 times the model surface static pressure, which is adequate to ensure sonic jets. The present results indicate that the jet penetration height for blowing was roughly half the height required with passive roughness elements for an equivalent amount of transition movement.

Evaluation and Application of Satellite-Based Latent Heating Profile Estimation Methods

NASA Technical Reports Server (NTRS)

Olson, William S.; Grecu, Mircea; Yang, Song; Tao, Wei-Kuo

2004-01-01

In recent years, methods for estimating atmospheric latent heating vertical structure from both passive and active microwave remote sensing have matured to the point where quantitative evaluation of these methods is the next logical step. Two approaches for heating algorithm evaluation are proposed: First, application of heating algorithms to synthetic data, based upon cloud-resolving model simulations, can be used to test the internal consistency of heating estimates in the absence of systematic errors in physical assumptions. Second, comparisons of satellite-retrieved vertical heating structures to independent ground-based estimates, such as rawinsonde-derived analyses of heating, provide an additional test. The two approaches are complementary, since systematic errors in heating indicated by the second approach may be confirmed by the first. A passive microwave and combined passive/active microwave heating retrieval algorithm are evaluated using the described approaches. In general, the passive microwave algorithm heating profile estimates are subject to biases due to the limited vertical heating structure information contained in the passive microwave observations. These biases may be partly overcome by including more environment-specific a priori information into the algorithm s database of candidate solution profiles. The combined passive/active microwave algorithm utilizes the much higher-resolution vertical structure information provided by spaceborne radar data to produce less biased estimates; however, the global spatio-temporal sampling by spaceborne radar is limited. In the present study, the passive/active microwave algorithm is used to construct a more physically-consistent and environment-specific set of candidate solution profiles for the passive microwave algorithm and to help evaluate errors in the passive algorithm s heating estimates. Although satellite estimates of latent heating are based upon instantaneous, footprint- scale data, suppression of random errors requires averaging to at least half-degree resolution. Analysis of mesoscale and larger space-time scale phenomena based upon passive and passive/active microwave heating estimates from TRMM, SSMI, and AMSR data will be presented at the conference.

Side-wall spacer passivated sub-μm Josephson junction fabrication process

NASA Astrophysics Data System (ADS)

Grönberg, Leif; Kiviranta, Mikko; Vesterinen, Visa; Lehtinen, Janne; Simbierowicz, Slawomir; Luomahaara, Juho; Prunnila, Mika; Hassel, Juha

2017-12-01

We present a structure and a fabrication method for superconducting tunnel junctions down to the dimensions of 200 nm using i-line UV lithography. The key element is a sidewall-passivating spacer structure (SWAPS) which is shaped for smooth crossline contacting and low parasitic capacitance. The SWAPS structure enables formation of junctions with dimensions at or below the lithography-limited linewidth. An additional benefit is avoiding the excessive use of amorphous dielectric materials which is favorable in sub-Kelvin microwave applications often plagued by nonlinear and lossy dielectrics. We apply the structure to niobium trilayer junctions, and provide characterization results yielding evidence on wafer-scale scalability, and critical current density tuning in the range of 0.1-3.0 kA cm-2. We discuss the applicability of the junction process in the context of different applications, such as SQUID magnetometers and Josephson parametric amplifiers.

The September 11 attack: A percolation of individual passive support

NASA Astrophysics Data System (ADS)

Galam, S.

2002-04-01

A model to terrorism is presented using the theory of percolation. Terrorism power is related to the spontaneous formation of random backbones of people who are sympathetic to terrorism but without being directly involved in it. They just don't oppose in case they could. In the past such friendly-to-terrorism backbones have been always existing but were of finite size and localized to a given geographical area. The September 11 terrorist attack on the US has revealed for the first time the existence of a world wide spread extension. It is argued to have result from a sudden world percolation of otherwise unconnected and dormant world spread backbones of passive supporters. The associated strategic question is then to determine if collecting ground information could have predict and thus avoid such a transition. Our results show the answer is no, voiding the major criticism against intelligence services. To conclude the impact of military action is discussed.

Avoidance behaviour of Eisenia fetida to carbofuran, chlorpyrifos, mancozeb and metamidophos in natural soils from the highlands of Colombia.

PubMed

García-Santos, Glenda; Keller-Forrer, Karin

2011-07-01

Earthworm avoidance behaviour test is an important screening tool in soil eco-toxicology. This test has been developed and validated under North American and European conditions. However, little research has been performed on the avoidance test in the tropics. This work demonstrates the potential suitability of the avoidance behaviour test as screening method in the highlands of Colombia using Eisenia fetida as the bio-indicator species on contaminated soils with carbofuran and chlorpyrifos. Though for the two active ingredients 100% avoidance was not reached, a curve with six meaningful concentrations is provided. No significant avoidance behaviour trend was found for mancozeb and methamidophos. Tests were conducted in the field yielded similar results to the tests carried out in the laboratory for chlorpyrifos and mancozeb. However, for the case of carbofuran and methamidophos, differences of more than double in avoidance were obtained. Divergence might be explained by soil and temperature conditions. Copyright © 2011 Elsevier Ltd. All rights reserved.

Intermittent fasting uncovers and rescues cognitive phenotypes in PTEN neuronal haploinsufficient mice.

PubMed

Cabral-Costa, J V; Andreotti, D Z; Mello, N P; Scavone, C; Camandola, S; Kawamoto, E M

2018-06-05

Phosphatase and tensin homolog (PTEN) is an important protein with key modulatory functions in cell growth and survival. PTEN is crucial during embryogenesis and plays a key role in the central nervous system (CNS), where it directly modulates neuronal development and synaptic plasticity. Loss of PTEN signaling function is associated with cognitive deficits and synaptic plasticity impairment. Accordingly, Pten mutations have a strong link with autism spectrum disorder. In this study, neuronal Pten haploinsufficient male mice were subjected to a long-term environmental intervention - intermittent fasting (IF) - and then evaluated for alterations in exploratory, anxiety and learning and memory behaviors. Although no significant effects on spatial memory were observed, mutant mice showed impaired contextual fear memory in the passive avoidance test - an outcome that was effectively rescued by IF. In this study, we demonstrated that IF modulation, in addition to its rescue of the memory deficit, was also required to uncover behavioral phenotypes otherwise hidden in this neuronal Pten haploinsufficiency model.

Nogo receptor 1 regulates formation of lasting memories.

PubMed

Karlén, Alexandra; Karlsson, Tobias E; Mattsson, Anna; Lundströmer, Karin; Codeluppi, Simone; Pham, Therese M; Bäckman, Cristina M; Ogren, Sven Ove; Aberg, Elin; Hoffman, Alexander F; Sherling, Michael A; Lupica, Carl R; Hoffer, Barry J; Spenger, Christian; Josephson, Anna; Brené, Stefan; Olson, Lars

2009-12-01

Formation of lasting memories is believed to rely on structural alterations at the synaptic level. We had found that increased neuronal activity down-regulates Nogo receptor-1 (NgR1) in brain regions linked to memory formation and storage, and postulated this to be required for formation of lasting memories. We now show that mice with inducible overexpression of NgR1 in forebrain neurons have normal long-term potentiation and normal 24-h memory, but severely impaired month-long memory in both passive avoidance and swim maze tests. Blocking transgene expression normalizes these memory impairments. Nogo, Lingo-1, Troy, endogenous NgR1, and BDNF mRNA expression levels were not altered by transgene expression, suggesting that the impaired ability to form lasting memories is directly coupled to inability to down-regulate NgR1. Regulation of NgR1 may therefore serve as a key regulator of memory consolidation. Understanding the molecular underpinnings of synaptic rearrangements that carry lasting memories may facilitate development of treatments for memory dysfunction.

Nogo receptor 1 regulates formation of lasting memories

PubMed Central

Karlén, Alexandra; Karlsson, Tobias E.; Mattsson, Anna; Lundströmer, Karin; Codeluppi, Simone; Pham, Therese M.; Bäckman, Cristina M.; Ögren, Sven Ove; Åberg, Elin; Hoffman, Alexander F.; Sherling, Michael A.; Lupica, Carl R.; Hoffer, Barry J.; Spenger, Christian; Josephson, Anna; Brené, Stefan; Olson, Lars

2009-01-01

Formation of lasting memories is believed to rely on structural alterations at the synaptic level. We had found that increased neuronal activity down-regulates Nogo receptor-1 (NgR1) in brain regions linked to memory formation and storage, and postulated this to be required for formation of lasting memories. We now show that mice with inducible overexpression of NgR1 in forebrain neurons have normal long-term potentiation and normal 24-h memory, but severely impaired month-long memory in both passive avoidance and swim maze tests. Blocking transgene expression normalizes these memory impairments. Nogo, Lingo-1, Troy, endogenous NgR1, and BDNF mRNA expression levels were not altered by transgene expression, suggesting that the impaired ability to form lasting memories is directly coupled to inability to down-regulate NgR1. Regulation of NgR1 may therefore serve as a key regulator of memory consolidation. Understanding the molecular underpinnings of synaptic rearrangements that carry lasting memories may facilitate development of treatments for memory dysfunction. PMID:19915139

Disclosure of research results in genetic studies of Parkinson's disease caused by LRRK2 mutations.

PubMed

Pont-Sunyer, Claustre; Bressman, Susan; Raymond, Deborah; Glickman, Amanda; Tolosa, Eduardo; Saunders-Pullman, Rachel

2015-06-01

With the advent of large genetic studies examining both symptomatic and asymptomatic individuals, whether and how to disclose genetic research results have become pressing questions. The need is particularly acute in the case of LRRK2 research: Movement centers worldwide are recruiting cohorts of individuals with Parkinson's disease (PD) and their family members, including asymptomatic carriers. Clinical features and treatment are complex and evolving, and disclosure policies vary at different sites and have been modified during the course of some studies. We present the major ethical principles of autonomy, beneficence, nonmaleficence, and honesty that should guide disclosure policies in studies of families with LRRK2 mutations. We make recommendations regarding genetic counseling, policies of either active or passive disclosure, responsibilities of funders to budget for genetic counseling, clinical genetic testing where locally required for disclosure, and aspects of study design to avoid mandatory disclosure whenever feasible. © 2015 International Parkinson and Movement Disorder Society. © 2015 International Parkinson and Movement Disorder Society.

Blockade of 5-HT2A/2C-type receptors impairs learning in female rats in the course of estrous cycle.

PubMed

Fedotova, Yu O; Ordyan, N E

2010-12-01

We studied the effects of chronic administration (14 days) of agonist of 5-HT2B/2C serotonin receptors m-CPP (0.5 mg/kg subcutaneously) and agonist of 5-HT2A/2C serotonin receptors ketanserin (0.1 mg/kg intraperitoneally) on conditioned reactions in female rats in different phases of the estrous cycle. Passive avoidance (PA) paradigm and Morris water maze were used as behavioral tests. Chronic administration of m-CPP did not affect PA retrieval during the proestrus and estrus phases, but improved the dynamics of spatial learning in Morris water maze in comparison with control rats. Chronic administration of ketanserin uniformly impaired processes of spatial and nonspatial learning in female rats irrespective to the phase of the estrous cycle. A modulating role of 5-HT2A/2C and 5-HT2B/2C serotonin receptors in process of learning in female rats during the key phases of the estrous cycle was demonstrated.

Cross-Cultural Variation in Political Leadership Styles

PubMed Central

Paramova, Petia; Blumberg, Herbert

2017-01-01

Guided by gaps in the literature with regard to the study of politicians the aim of the research is to explore cross-cultural differences in political leaders’ style. It compares the MLQ (Avolio & Bass, 2004) scores of elected political leaders (N = 140) in Bulgaria and the UK. The statistical exploration of the data relied on multivariate analyses of covariance. The findings of comparisons across the two groups reveal that compared to British political leaders, Bulgarian leaders were more likely to frequently use both transactional and passive/avoidant behaviours. The study tests Bass’s (1997) strong assertion about the universality of transformational leadership. It contributes to the leadership literature by providing directly measured data relating to the behaviours of political leaders. Such information on the characteristics of politicians could allow for more directional hypotheses in subsequent research, exploring the contextual influences within transformational leadership theory. The outcomes might also aid applied fields. Knowledge gained of culturally different leaders could be welcomed by multicultural political and economic unions, wherein understanding and allowances might aid communication. PMID:29358986

The impact of using different doses of progesterone on memory performance.

PubMed

Roozbehi, A; Sharafi, M T; Karimi, F; Kamali, A M

2017-01-01

Progesterone is a sex hormone and its receptors are expressed throughout the hippocampus. This study was aimed at evaluating the effects of different doses of progesterone on memory. Male rats were arbitrarily assigned to nine groups, namely Group I: control, Group II: control-cannula, Group III received 0.5 μl of saline by cannula, Groups IV , V, VI, VII and VIII received progesterone in doses of 0.5, 1, 1.5, 2, and 3 μg/ 0.5 μl by cannula, respectively. Group IX received 0.5 μl almond oil by cannula. Memory performance was tested in form of passive avoidance task. Our results indicated that progesterone at doses of 1.5 and 2 µg (p < 0.05) significantly increased the memory performance while at a dose of 3 µg (p < 0.05), it significantly decreased memory as compared to the control group. The current study revealed that the influence of progesterone on memory is related to its dose (Fig. 1, Ref. 25).

Cross-Cultural Variation in Political Leadership Styles.

PubMed

Paramova, Petia; Blumberg, Herbert

2017-11-01

Guided by gaps in the literature with regard to the study of politicians the aim of the research is to explore cross-cultural differences in political leaders' style. It compares the MLQ (Avolio & Bass, 2004) scores of elected political leaders (N = 140) in Bulgaria and the UK. The statistical exploration of the data relied on multivariate analyses of covariance. The findings of comparisons across the two groups reveal that compared to British political leaders, Bulgarian leaders were more likely to frequently use both transactional and passive/avoidant behaviours. The study tests Bass's (1997) strong assertion about the universality of transformational leadership. It contributes to the leadership literature by providing directly measured data relating to the behaviours of political leaders. Such information on the characteristics of politicians could allow for more directional hypotheses in subsequent research, exploring the contextual influences within transformational leadership theory. The outcomes might also aid applied fields. Knowledge gained of culturally different leaders could be welcomed by multicultural political and economic unions, wherein understanding and allowances might aid communication.

Proceedings of Damping 1993, volume 3

NASA Astrophysics Data System (ADS)

Portis, Bonnie L.

1993-06-01

Presented are individual papers of Damping '93, held 24-26 February 1993 in San Francisco. The subjects included: passive damping concepts; passive damping analysis and design techniques; optimization; damped control/structure interaction; viscoelastic material testing and characterization; highly damped materials; vibration suppression techniques; damping identification and dynamic testing; applications to aircraft; space structures; Marine structures; and commercial products; defense applications; and payoffs of vibration suppression.

Proceedings of Damping 1993, volume 1

NASA Astrophysics Data System (ADS)

Portis, Bonnie L.

1993-06-01

Presented are individual papers of Damping '93 held 24-26 February, 1993, in San Francisco. The subjects included: passive damping concepts; passive damping analysis and design techniques; optimization; damped control/structure interaction; viscoelastic material testing and characterization; highly damped materials; vibration suppression techniques; damping identification and dynamic testing; application to aircraft; space structures; marine structures; commercial products; defense applications; and payoffs of vibration suppression.

The effects of N-Methyl-D-Aspartate receptor blockade during the early neurodevelopmental period on emotional behaviors and cognitive functions of adolescent Wistar rats.

PubMed

Kocahan, Sayad; Akillioglu, Kubra; Binokay, Secil; Sencar, Leman; Polat, Sait

2013-05-01

The N-Methyl-D-Aspartate (NMDA) receptor is expressed abundantly in the brain and plays an important role in neuronal development, learning and memory, neurodegenerative diseases, and neurogenesis. In this study, we evaluated the effects of NMDA receptor blockade during the early neurodevelopmental period on exploratory locomotion, anxiety-like behaviors and cognitive functions of adolescent Wistar rats. NMDA receptor hypofunction was induced 7-10 days after birth using MK-801 in rats (0.25 mg/kg twice a day for 4 days via intraperitoneal injection). The open-field (OF), elevated plus maze (EPM) and passive avoidance (PA) tests were used to evaluate exploratory locomotion, anxiety-like behaviors and cognitive functions. In the OF test, MK-801 caused an increase in locomotion behavior (p < 0.01) and in the frequency of rearing (p < 0.05). In the EPM test, MK-801 treatment increased the time spent in the open arms, the number of open arm entries and the amount of head dipping (p < 0.01). MK-801 treatment caused no statistical difference compared to the control group in the PA test (p > 0.05). Chronic NMDA receptor blockade during the critical period of maturation for the glutamatergic brain system (postnatal days 7-10) produces locomotor hyperactivity and decreased anxiety levels, but has no significant main effect on cognitive function during adolescence.

Molecular simplification of 1,4-diazabicyclo[4.3.0]nonan-9-ones gives piperazine derivatives that maintain high nootropic activity.

PubMed

Manetti, D; Ghelardini, C; Bartolini, A; Dei, S; Galeotti, N; Gualtieri, F; Romanelli, M N; Teodori, E

2000-11-16

Several 4-substituted 1-acylpiperazines, obtained by molecular simplification of 4-substituted 1,4-diazabicyclo[4.3.0]nonan-9-ones, have been synthesized and tested in vivo on the mouse passive avoidance test, to evaluate their nootropic activity. The results show that, apparently, an N-acylpiperazine group can mimic the 2-pyrrolidinone ring of 1,4-diazabicyclo[4.3.0]nonan-9-one, as the compounds of the new series maintain high nootropic activity. Moreover molecular simplification produces more clear-cut structure-activity relationships with respect to the parent series. The mechanism of action also appears to be similar in the two series. In fact, although the molecular mechanism remains to be elucidated, the most potent compound of each class (DM232 and 13, DM235) is able to increase acetylcholine release in rat brain. Piperazine derivatives represent a new class of nootropic drugs with an in vivo pharmacological profile very similar to that of piracetam, showing much higher potency with respect to the reference compound. Among the compounds studied, 13 (DM235) shows outstanding potency, being active at a dose of 0.001 mg kg(-1) sc.

Behavioral testing of mice exposed to intermediate frequency magnetic fields indicates mild memory impairment.

PubMed

Kumari, Kajal; Koivisto, Hennariikka; Viluksela, Matti; Paldanius, Kaisa M A; Marttinen, Mikael; Hiltunen, Mikko; Naarala, Jonne; Tanila, Heikki; Juutilainen, Jukka

2017-01-01

Human exposure to intermediate frequency magnetic fields (MF) is increasing due to applications like electronic article surveillance systems and induction heating cooking hobs. However, limited data is available on their possible health effects. The present study assessed behavioral and histopathological consequences of exposing mice to 7.5 kHz MF at 12 or 120 μT for 5 weeks. No effects were observed on body weight, spontaneous activity, motor coordination, level of anxiety or aggression. In the Morris swim task, mice in the 120 μT group showed less steep learning curve than the other groups, but did not differ from controls in their search bias in the probe test. The passive avoidance task indicated a clear impairment of memory over 48 h in the 120 μT group. No effects on astroglial activation or neurogenesis were observed in the hippocampus. The mRNA expression of brain-derived neurotrophic factor did not change but expression of the proinflammatory cytokine tumor necrosis factor alpha mRNA was significantly increased in the 120 μT group. These findings suggest that 7.5 kHz MF exposure may lead to mild learning and memory impairment, possibly through an inflammatory reaction in the hippocampus.

Cannabis Allergy: What do We Know Anno 2015.

PubMed

Decuyper, Ine; Ryckebosch, Hanne; Van Gasse, Athina L; Sabato, Vito; Faber, Margaretha; Bridts, Chris H; Ebo, Didier G

2015-10-01

For about a decade, IgE-mediated cannabis (marihuana) allergy seems to be on the rise. Both active and passive exposure to cannabis allergens may lead to a cannabis sensitization and/or allergy. The clinical manifestations of a cannabis allergy can vary from mild to life-threatening reactions, often depending on the route of exposure. In addition, sensitization to cannabis allergens can trigger various secondary cross-allergies, mostly for plant-derived food. This clinical entity, which we have designated as the "cannabis-fruit/vegetable syndrome" might also imply cross-reactivity with tobacco, latex and plant-food derived alcoholic beverages. These secondary cross-allergies are mainly described in Europe and appear to result from cross-reactivity between non-specific lipid transfer proteins or thaumatin-like proteins present in Cannabis sativa and their homologues that are ubiquitously distributed throughout plant kingdom. At present, diagnosis of cannabis-related allergies rests upon a thorough history completed with skin testing using native extracts from buds and leaves. However, quantification of specific IgE antibodies and basophil activation tests can also be helpful to establish correct diagnosis. In the absence of a cure, treatment comprises absolute avoidance measures including a stop of any further cannabis (ab)use.

Antiamnesic Effect of Actinidia arguta Extract Intake in a Mouse Model of TMT-Induced Learning and Memory Dysfunction

PubMed Central

Ha, Jeong Su; Jin, Dong Eun; Park, Seon Kyeong; Park, Chang Hyeon; Seung, Tae Wan; Bae, Dong-Won; Kim, Dae-Ok; Heo, Ho Jin

2015-01-01

The antiamnesic effects of ethyl acetate fraction from Actinidia arguta (EFAA) on trimethyltin- (TMT-) induced memory impairment were investigated to find the possibility of functional food substances. EFAA showed a potent AChE inhibitory effect (IC50 = 53 μg/mL) and efficient neuroprotection against H2O2-induced oxidative stress. The administration of EFAA significantly decreased TMT-induced cognitive deficit in Y-maze, passive avoidance, and Morris water maze (MWM) tests. After the behavioral tests, the antioxidant activities were confirmed using mice brain tissues. EFAA not only showed the inhibition of AChE activity and the decline of malondialdehyde (MDA) level as a sign of lipid peroxidation but also presented the increase of the superoxide dismutase (SOD) level and the decrease of the oxidized glutathione (GSSG)/total glutathione (GSH + GSSG) ratio. Finally, the phenolics in EFAA were identified using liquid chromatography coupled with hybrid triple quadrupole-linear ion trap mass spectrometry, and four main phenolics, such as quinic acid, chlorogenic acid, caffeoyl hexose, and quercetin-3-glucoside, were identified. These results suggest that EFAA containing physiological phenolics might enhance drug-induced amnesia through AChE inhibition and neuroprotection. PMID:26576196