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Sample records for eyeblink conditioned responses

  1. Spontaneous Recovery But Not Reinstatement of the Extinguished Conditioned Eyeblink Response in the Rat

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    Thanellou, Alexandra; Green, John T.

    2011-01-01

    Reinstatement, the return of an extinguished conditioned response (CR) after reexposure to the unconditioned stimulus (US), and spontaneous recovery, the return of an extinguished CR with the passage of time, are two of four well-established phenomena which demonstrate that extinction does not erase the conditioned stimulus (CS)-US association. However, reinstatement of extinguished eyeblink CRs has never been demonstrated and spontaneous recovery of extinguished eyeblink CRs has not been systematically demonstrated in rodent eyeblink conditioning. In Experiment 1, US reexposure was administered 24 hours prior to a reinstatement test. In Experiment 2, US reexposure was administered 5 min prior to a reinstatement test. In Experiment 3, a long, discrete cue (a houselight), present in all phases of training and testing, served as a context within which each trial occurred to maximize context processing, which in other preparations has been shown to be required for reinstatement. In Experiment 4, an additional group was included that received footshock exposure, rather than US reexposure, between extinction and test, and contextual freezing was measured prior to test. Spontaneous recovery was robust in Experiments 3 and 4. In Experiment 4, context freezing was strong in a group given footshock exposure but not in a group given eyeshock US reexposure. There was no reinstatement observed in any experiment. With stimulus conditions that produce eyeblink conditioning and research designs that produce reinstatement in other forms of classical conditioning, we observed spontaneous recovery but not reinstatement of extinguished eyeblink CRs. This suggests that reinstatement, but not spontaneous recovery, is a preparation- or substrate-dependent phenomenon. PMID:21517145

  2. Lack of renewal effect in extinction of naturally acquired conditioned eyeblink responses, but possible dependency on physical context.

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    Claassen, J; Mazilescu, L; Thieme, A; Bracha, V; Timmann, D

    2016-01-01

    Context dependency of extinction is well known and has extensively been studied in fear conditioning, but has rarely been assessed in eyeblink conditioning. One way to demonstrate context dependency of extinction is the renewal effect. ABA paradigms are most commonly used to show the renewal effect of extinguished learned fear: if acquisition takes place in context A, and extinction takes place in context B (extinction phase), learned responses will recover in subsequent extinction trials presented in context A (renewal phase). The renewal effect of the visual threat eyeblink response (VTER), a conditioned eyeblink response, which is naturally acquired in early infancy, was examined in a total of 48 young and healthy participants with two experiments using an ABA paradigm. Twenty paired trials were performed in context A (baseline trials), followed by 50 extinction trials in context B (extinction phase) and 50 extinction trials in context A (renewal phase). In 24 participants, contexts A and B were two different rooms, and in the other 24 participants, two different background colors (orange and blue) and noises were used. To rule out spontaneous recovery, an AAA design was used for comparison. There were significant effects of extinction in both experiments. No significant renewal effects were observed. In experiment 2, however, extinction was significantly less using orange background during extinction compared to the blue background. The present findings suggest that extinction of conditioned eyeblinks depends on the physical context. Findings add to the animal literature that context can play a role in the acquisition of classically conditioned eyeblink responses. Future studies, however, need to be performed to confirm the present findings. Lack of renewal effect may be explained by the highly overlearned character of the VTER.

  3. Classical eyeblink conditioning in Parkinson's disease.

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    Daum, I; Schugens, M M; Breitenstein, C; Topka, H; Spieker, S

    1996-11-01

    Patients with Parkinson's disease (PD) show impairments of a range of motor learning tasks, including tracking or serial reaction time task learning. Our study investigated whether such deficits would also be seen on a simple type of motor learning, classic conditioning of the eyeblink response. Medicated and unmediated patients with PD showed intact unconditioned eyeblink responses and significant learning across acquisition; the learning rates did not differ from those of healthy control subjects. The overall frequency of conditioned responses was significantly higher in the medicated patients with PD relative to control subjects, and there was also some evidence of facilitation in the unmedicated patients with PD. Conditioning of electrodermal and electrocortical responses was comparable in all groups. The findings are discussed in terms of enhanced excitability of brainstem pathways in PD and of the involvement of different neuronal circuits in different types of motor learning.

  4. Children with autism spectrum disorders show abnormal conditioned response timing on delay, but not trace, eyeblink conditioning

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    Oristaglio, Jeff; West, Susan Hyman; Ghaffari, Manely; Lech, Melissa S.; Verma, Beeta R.; Harvey, John A.; Welsh, John P.; Malone, Richard P.

    2013-01-01

    Children with autism spectrum disorder (ASD) and age-matched typically-developing (TD) peers were tested on two forms of eyeblink conditioning (EBC), a Pavlovian associative learning paradigm where subjects learn to execute an appropriately-timed eyeblink in response to a previously neutral conditioning stimulus (CS). One version of the task, trace EBC, interposes a stimulus-free interval between the presentation of the CS and the unconditioned stimulus (US), a puff of air to the eye which causes subjects to blink. In delay EBC, the CS overlaps in time with the delivery of the US, usually with both stimuli terminating simultaneously. ASD children performed normally during trace EBC, exhibiting no differences from typically-developing (TD) subjects with regard to learning rate or the timing of the CR. However, when subsequently tested on delay EBC, subjects with ASD displayed abnormally-timed conditioned eye blinks that began earlier and peaked sooner than those of TD subjects, consistent with previous findings. The results suggest an impaired ability of children with ASD to properly time conditioned eye blinks which appears to be specific to delay EBC. We suggest that this deficit may reflect a dysfunction of cerebellar cortex in which increases in the intensity or duration of sensory input can temporarily disrupt the accuracy of motor timing over short temporal intervals. PMID:23769889

  5. Savings and extinction of conditioned eyeblink responses in fragile X syndrome

    DEFF Research Database (Denmark)

    Smit, A E; van der Geest, J N; Vellema, M

    2008-01-01

    with FRAXA. In the present behavioral study, long-term effects of deficiency of FMRP were investigated by examining the acquisition, savings and extinction of delay eyeblink conditioning in male individuals with FRAXA. In the acquisition experiment, subjects with FRAXA displayed a significantly poor...... of the FMRP affects cerebellar motor learning. The normal performance in the savings experiment and aberrant performance in the acquisition and extinction experiments of individuals with FRAXA suggest that different mechanisms underlie acquisition, savings and extinction of cerebellar motor learning....

  6. Enhanced conditioned eyeblink response acquisition and proactive interference in anxiety vulnerable individuals

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    Jacqueline L Holloway

    2012-11-01

    Full Text Available In classical conditioning, proactive interference may arise from experience with the conditioned stimulus (CS, the unconditional stimulus (US, or both, prior to their paired presentations. Interest in the application of proactive interference has extended to clinical populations as either a risk factor for disorders or as a secondary sign. Although the current literature is dense with comparisons of stimulus pre-exposure effects in animals, such comparisons are lacking in human subjects. As such, interpretation of proactive interference over studies as well as its generalization and utility in clinical research is limited. The present study was designed to assess eyeblink response acquisition after equal numbers of CS, US, and explicitly unpaired CS and US pre-exposures, as well as to evaluate how anxiety vulnerability might modulate proactive interference. In the current study, anxiety vulnerability was assessed using the State/Trait Anxiety Inventories as well as the adult and retrospective measures of behavioural inhibition (AMBI and RMBI, respectively. Participants were exposed to 1 of 4 possible pre-exposure contingencies: 30 CS, 30 US, 30 CS and 30 US explicitly unpaired pre-exposures, or context pre-exposure, immediately prior to standard delay training. Robust proactive interference was evident in all pre-exposure groups relative to context pre-exposure, independent of anxiety classification, with CR acquisition attenuated at similar rates. In addition, trait anxious individuals were found to have enhanced overall acquisition as well as greater proactive interference relative to non-vulnerable individuals. The findings suggest that anxiety vulnerable individuals learn implicit associations faster, an effect which persists after the introduction of new stimulus contingencies. This effect is not due to enhanced sensitivity to the US. Such differences would have implications for the development of anxiety psychopathology within a learning

  7. Enhanced conditioned eyeblink response acquisition and proactive interference in anxiety vulnerable individuals.

    Science.gov (United States)

    Holloway, Jacqueline L; Trivedi, Payal; Myers, Catherine E; Servatius, Richard J

    2012-01-01

    In classical conditioning, proactive interference may arise from experience with the conditioned stimulus (CS), the unconditional stimulus (US), or both, prior to their paired presentations. Interest in the application of proactive interference has extended to clinical populations as either a risk factor for disorders or as a secondary sign. Although the current literature is dense with comparisons of stimulus pre-exposure effects in animals, such comparisons are lacking in human subjects. As such, interpretation of proactive interference over studies as well as its generalization and utility in clinical research is limited. The present study was designed to assess eyeblink response acquisition after equal numbers of CS, US, and explicitly unpaired CS and US pre-exposures, as well as to evaluate how anxiety vulnerability might modulate proactive interference. In the current study, anxiety vulnerability was assessed using the State/Trait Anxiety Inventories as well as the adult and retrospective measures of behavioral inhibition (AMBI and RMBI, respectively). Participants were exposed to 1 of 4 possible pre-exposure contingencies: 30 CS, 30 US, 30 CS, and 30 US explicitly unpaired pre-exposures, or Context pre-exposure, immediately prior to standard delay training. Robust proactive interference was evident in all pre-exposure groups relative to Context pre-exposure, independent of anxiety classification, with CR acquisition attenuated at similar rates. In addition, trait anxious individuals were found to have enhanced overall acquisition as well as greater proactive interference relative to non-vulnerable individuals. The findings suggest that anxiety vulnerable individuals learn implicit associations faster, an effect which persists after the introduction of new stimulus contingencies. This effect is not due to enhanced sensitivity to the US. Such differences would have implications for the development of anxiety psychopathology within a learning framework.

  8. Evidence of plasticity in the pontocerebellar conditioned stimulus pathway during classical conditioning of the eyeblink response in the rabbit.

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    Tracy, Jo Anne; Thompson, Judith K; Krupa, David J; Thompson, Richard F

    2013-10-01

    Electrical stimulation thresholds required to elicit eyeblinks with either pontine or cerebellar interpositus stimulation were measured before and after classical eyeblink conditioning with paired pontine stimulation (conditioned stimulus, CS) and corneal airpuff (unconditioned stimulus, US). Pontine stimulation thresholds dropped dramatically after training and returned to baseline levels following extinction, whereas interpositus thresholds and input-output functions remained stable across training sessions. Learning rate, magnitude of threshold change, and electrode placements were correlated. Pontine projection patterns to the cerebellum were confirmed with retrograde labeling techniques. These results add to the body of literature suggesting that the pons relays CS information to the cerebellum and provide further evidence of synaptic plasticity in the cerebellar network. 2013 APA, all rights reserved

  9. Eyeblink conditioning is impaired in subjects with essential tremor.

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    Kronenbuerger, Martin; Gerwig, Marcus; Brol, Beate; Block, Frank; Timmann, Dagmar

    2007-06-01

    Several lines of evidence point to an involvement of the olivo-cerebellar system in the pathogenesis of essential tremor (ET), with clinical signs of cerebellar dysfunction being present in some subjects in the advanced stage. Besides motor coordination, the cerebellum is critically involved in motor learning. Evidence of motor learning deficits would strengthen the hypothesis of olivo-cerebellar involvement in ET. Conditioning of the eyeblink reflex is a well-established paradigm to assess motor learning. Twenty-three ET subjects (13 males, 10 females; mean age 44.3 +/- 22.3 years, mean disease duration 17.4 +/- 17.3 years) and 23 age-matched healthy controls were studied on two consecutive days using a standard delay eyeblink conditioning protocol. Six ET subjects exhibited accompanying clinical signs of cerebellar dysfunction. Care was taken to examine subjects without medication affecting central nervous functioning. Seven ET subjects and three controls on low-dose beta-blocker treatments, which had no effect on eyeblink conditioning in animal studies, were allowed into the study. The ability to acquire conditioned eyeblink responses was significantly reduced in ET subjects compared with controls. Impairment of eyeblink conditioning was not due to low-dose beta-blocker medication. Additionally, acquisition of conditioned eyeblink response was reduced in ET subjects regardless of the presence of cerebellar signs in clinical examination. There were no differences in timing or extinction of conditioned responses between groups and conditioning deficits did not correlate with the degree of tremor or ataxia as rated by clinical scores. The findings of disordered eyeblink conditioning support the hypothesis that ET is caused by a functional disturbance of olivo-cerebellar circuits which may cause cerebellar dysfunction. In particular, results point to an involvement of the olivo-cerebellar system in early stages of ET.

  10. Performance in eyeblink conditioning is age and sex dependent.

    Directory of Open Access Journals (Sweden)

    Karolina Löwgren

    Full Text Available A growing body of evidence suggests that the cerebellum is involved in both cognition and language. Abnormal cerebellar development may contribute to neurodevelopmental disorders such as attention deficit hyperactivity disorder (ADHD, autism, fetal alcohol syndrome, dyslexia, and specific language impairment. Performance in eyeblink conditioning, which depends on the cerebellum, can potentially be used to clarify the neural mechanisms underlying the cerebellar dysfunction in disorders like these. However, we must first understand how the performance develops in children who do not have a disorder. In this study we assessed the performance in eyeblink conditioning in 42 typically developing children between 6 and 11 years old as well as in 26 adults. Older children produced more conditioned eyeblink responses than younger children and adults produced more than children. In addition, females produced more conditioned eyeblink responses than males among both children and adults. These results highlight the importance of considering the influence of age and sex on the performance when studying eyeblink conditioning as a measure of cerebellar development.

  11. Autism and classical eyeblink conditioning: Performance changes of the conditioned response related to autism spectrum disorder diagnosis

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    John P Welsh

    2016-08-01

    Full Text Available Changes in the timing performance of conditioned responses (CRs acquired during trace and delay eyeblink conditioning (EBC are presented for diagnostic subgroups of children having autism spectrum disorder (ASD aged 6-15 years. Children diagnosed with autistic disorder (AD were analyzed separately from children diagnosed with either Asperger’s syndrome or Pervasive-developmental disorder not-otherwise-specified (Asp/PDD and compared to an age- and IQ-matched group of children that were typically developing (TD. Within-subject and between-groups contrasts in CR performance on sequential exposure to trace and delay EBC were analyzed to determine whether any differences would expose underlying functional heterogeneities of the cerebral and cerebellar systems in ASD subgroups. The EBC parameters measured were percentage CRs, CR onset latency, and CR peak latency. Neither AD nor Asp/PDD groups were impaired in CR acquisition during trace or delay EBC. AD and Asp/PDD both altered CR timing, but not always in the same way. Although the AD group showed normal CR timing during trace EBC, the Asp/PDD group showed a significant 27 and 28 ms increase in CR onset and peak latency, respectively, during trace EBC. In contrast, the direction of the timing change was opposite during delay EBC, during which the Asp/PDD group showed a significant 29 ms decrease in CR onset latency and the AD group showed a larger 77 ms decrease in CR onset latency. Only the AD group showed a decrease in CR peak latency during delay EBC, demonstrating another difference between AD and Asp/PDD. The difference in CR onset latency during delay EBC for both AD and Asp/PDD was due to an abnormal prevalence of early onset CRs that were intermixed with CRs having normal timing, as observed both in CR onset histograms and mean CR waveforms. In conclusion, significant heterogeneity in EBC performance was apparent within diagnostic groups, and this may indicate that EBC performance can

  12. Modulation of 7 T fMRI Signal in the Cerebellar Cortex and Nuclei During Acquisition, Extinction, and Reacquisition of Conditioned Eyeblink Responses.

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    Ernst, Thomas M; Thürling, Markus; Müller, Sarah; Kahl, Fabian; Maderwald, Stefan; Schlamann, Marc; Boele, Henk-Jan; Koekkoek, Sebastiaan K E; Diedrichsen, Jörn; De Zeeuw, Chris I; Ladd, Mark E; Timmann, Dagmar

    2017-08-01

    Classical delay eyeblink conditioning is likely the most commonly used paradigm to study cerebellar learning. As yet, few studies have focused on extinction and savings of conditioned eyeblink responses (CRs). Saving effects, which are reflected in a reacquisition after extinction that is faster than the initial acquisition, suggest that learned associations are at least partly preserved during extinction. In this study, we tested the hypothesis that acquisition-related plasticity is nihilated during extinction in the cerebellar cortex, but retained in the cerebellar nuclei, allowing for faster reacquisition. Changes of 7 T functional magnetic resonance imaging (fMRI) signals were investigated in the cerebellar cortex and nuclei of young and healthy human subjects. Main effects of acquisition, extinction, and reacquisition against rest were calculated in conditioned stimulus-only trials. First-level β values were determined for a spherical region of interest (ROI) around the acquisition peak voxel in lobule VI, and dentate and interposed nuclei ipsilateral to the unconditioned stimulus. In the cerebellar cortex and nuclei, fMRI signals were significantly lower in extinction compared to acquisition and reacquisition, but not significantly different between acquisition and reacquisition. These findings are consistent with the theory of bidirectional learning in both the cerebellar cortex and nuclei. It cannot explain, however, why conditioned responses reappear almost immediately in reacquisition following extinction. Although the present data do not exclude that part of the initial memory remains in the cerebellum in extinction, future studies should also explore changes in extracerebellar regions as a potential substrate of saving effects. Hum Brain Mapp 38:3957-3974, 2017. © 2017 Wiley Periodicals, Inc. © 2017 Wiley Periodicals, Inc.

  13. Effects of systemic glutamatergic manipulations on conditioned eyeblink responses and hyperarousal in a rabbit model of post-traumatic stress disorder.

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    Burhans, Lauren B; Smith-Bell, Carrie A; Schreurs, Bernard G

    2017-10-01

    Glutamatergic dysfunction is implicated in many neuropsychiatric conditions, including post-traumatic stress disorder (PTSD). Glutamate antagonists have shown some utility in treating PTSD symptoms, whereas glutamate agonists may facilitate cognitive behavioral therapy outcomes. We have developed an animal model of PTSD, based on conditioning of the rabbit's eyeblink response, that addresses two key features: conditioned responses (CRs) to cues associated with an aversive event and a form of conditioned hyperarousal referred to as conditioning-specific reflex modification (CRM). The optimal treatment to reduce both CRs and CRM is unpaired extinction. The goals of the study were to examine whether treatment with the N-methyl-D-aspartate glutamate receptor antagonist ketamine could reduce CRs and CRM, and whether the N-methyl-D-aspartate agonist D-cycloserine combined with unpaired extinction treatment could enhance the extinction of both. Administration of a single dose of subanesthetic ketamine had no significant immediate or delayed effect on CRs or CRM. Combining D-cycloserine with a single day of unpaired extinction facilitated extinction of CRs in the short term while having no impact on CRM. These results caution that treatments may improve one aspect of the PTSD symptomology while having no significant effects on other symptoms, stressing the importance of a multiple-treatment approach to PTSD and of animal models that address multiple symptoms.

  14. Eyeblink Conditioning: A Non-Invasive Biomarker for Neurodevelopmental Disorders

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    Reeb-Sutherland, Bethany C.; Fox, Nathan A.

    2015-01-01

    Eyeblink conditioning (EBC) is a classical conditioning paradigm typically used to study the underlying neural processes of learning and memory. EBC has a well-defined neural circuitry, is non-invasive, and can be employed in human infants shortly after birth making it an ideal tool to use in both developing and special populations. In addition,…

  15. Extinction, Reacquisition, and Rapid Forgetting of Eyeblink Conditioning in Developing Rats

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    Brown, Kevin L.; Freeman, John H.

    2014-01-01

    Eyeblink conditioning is a well-established model for studying the developmental neurobiology of associative learning and memory. However, age differences in extinction and subsequent reacquisition have yet to be studied using this model. The present study examined extinction and reacquisition of eyeblink conditioning in developing rats. In…

  16. Retention and Extinction of Delay Eyeblink Conditioning Are Modulated by Central Cannabinoids

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    Steinmetz, Adam B.; Freeman, John H.

    2011-01-01

    Rats administered the cannabinoid agonist WIN55,212-2 or the antagonist SR141716A exhibit marked deficits during acquisition of delay eyeblink conditioning, as noted by Steinmetz and Freeman in an earlier study. However, the effects of these drugs on retention and extinction of eyeblink conditioning have not been assessed. The present study…

  17. Medial Auditory Thalamic Stimulation as a Conditioned Stimulus for Eyeblink Conditioning in Rats

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    Campolattaro, Matthew M.; Halverson, Hunter E.; Freeman, John H.

    2007-01-01

    The neural pathways that convey conditioned stimulus (CS) information to the cerebellum during eyeblink conditioning have not been fully delineated. It is well established that pontine mossy fiber inputs to the cerebellum convey CS-related stimulation for different sensory modalities (e.g., auditory, visual, tactile). Less is known about the…

  18. Impaired memory of eyeblink conditioning in CaMKIV KO mice.

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    Lee, Ka Hung; Chatila, Talal A; Ram, Rana A; Thompson, Richard F

    2009-04-01

    The calcium/calmodulin-dependent protein kinase type IV (CaMKIV) is highly expressed in cerebellar cortical granule cells and deep nuclear neurons in the cerebellum. It mediates the phosphorylation and activation of the cAMP-dependent response element binding protein (CREB). In several paradigms CREB-dependent transcription is required for cellular events underlying long-term memory processes. Also, CaMKIV deficiency results in impaired long-term depression (LTD) induction in cerebellar cortex. To investigate the function of CaMKIV in the cerebellum, Wild-type (WT) and CaMKIV KO mice were tested with delay eyeblink conditioning. KO and WT mice did not differ in acquisition, but the KO mice showed a significantly lower conditioned response (CR) percentage than the WT mice in the retention testing and retraining period. The CR peak latencies for the two groups did not differ in acquisition but were shorter for the KO mice in the testing period. No significant differences were found between KO and WT mice in spontaneous eyeblink activity, auditory brainstem response (ABR) amplitudes, and tail-flick latency. The results suggest an important role for CaMKIV in long-term memory in the cerebellum. (c) 2009 APA, all rights reserved.

  19. Hippocampal theta activity is selectively associated with contingency detection but not discrimination in rabbit discrimination-reversal eyeblink conditioning.

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    Nokia, Miriam S; Wikgren, Jan

    2010-04-01

    The relative power of the hippocampal theta-band ( approximately 6 Hz) activity (theta ratio) is thought to reflect a distinct neural state and has been shown to affect learning rate in classical eyeblink conditioning in rabbits. We sought to determine if the theta ratio is mostly related to the detection of the contingency between the stimuli used in conditioning or also to the learning of more complex inhibitory associations when a highly demanding delay discrimination-reversal eyeblink conditioning paradigm is used. A high hippocampal theta ratio was not only associated with a fast increase in conditioned responding in general but also correlated with slow emergence of discriminative responding due to sustained responding to the conditioned stimulus not paired with an unconditioned stimulus. The results indicate that the neural state reflected by the hippocampal theta ratio is specifically linked to forming associations between stimuli rather than to the learning of inhibitory associations needed for successful discrimination. This is in line with the view that the hippocampus is responsible for contingency detection in the early phase of learning in eyeblink conditioning. (c) 2009 Wiley-Liss, Inc.

  20. The Role of Contingency Awareness in Single-Cue Human Eyeblink Conditioning

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    Weidemann, Gabrielle; Best, Erin; Lee, Jessica C; Lovibond, Peter F.

    2013-01-01

    Single-cue delay eyeblink conditioning is presented as a prototypical example of automatic, nonsymbolic learning that is carried out by subcortical circuits. However, it has been difficult to assess the role of cognition in single-cue conditioning because participants become aware of the simple stimulus contingency so quickly. In this experiment…

  1. Medial Auditory Thalamus Is Necessary for Acquisition and Retention of Eyeblink Conditioning to Cochlear Nucleus Stimulation

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    Halverson, Hunter E.; Poremba, Amy; Freeman, John H.

    2015-01-01

    Associative learning tasks commonly involve an auditory stimulus, which must be projected through the auditory system to the sites of memory induction for learning to occur. The cochlear nucleus (CN) projection to the pontine nuclei has been posited as the necessary auditory pathway for cerebellar learning, including eyeblink conditioning.…

  2. Cholinergic Septo-Hippocampal Innervation Is Required for Trace Eyeblink Classical Conditioning

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    Fontan-Lozano, Angela; Troncoso, Julieta; Munera, Alejandro; Carrion, Angel Manuel; Delgado-Garcia, Jose Maria

    2005-01-01

    We studied the effects of a selective lesion in rats, with 192-IgG-saporin, of the cholinergic neurons located in the medial septum/diagonal band (MSDB) complex on the acquisition of classical and instrumental conditioning paradigms. The MSDB lesion induced a marked deficit in the acquisition, but not in the retrieval, of eyeblink classical…

  3. Eyeblink Classical Conditioning and Post Traumatic Stress Disorder – A Model Systems Approach

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    Bernard G Schreurs

    2015-04-01

    Full Text Available Not everyone exposed to trauma suffers flashbacks, bad dreams, numbing, fear, anxiety, sleeplessness, hyper-vigilance, hyperarousal, or an inability to cope, but those who do may suffer from post traumatic stress disorder (PTSD. PTSD is a major physical and mental health problem for military personnel and civilians exposed to trauma. There is still debate about the incidence and prevalence of PTSD especially among the military, but for those who are diagnosed, behavioral therapy and drug treatment strategies have proven to be less than effective. A number of these treatment strategies are based on rodent fear conditioning research and are capable of treating only some of the symptoms because the extinction of fear does not deal with the various forms of hyper-vigilance and hyperarousal experienced by people with PTSD. To help address this problem, we have developed a preclinical eyeblink classical conditioning model of PTSD in which conditioning and hyperarousal can both be extinguished. We review this model and discuss findings showing that unpaired stimulus presentations can be effective in reducing levels of conditioning and hyperarousal even when unconditioned stimulus intensity is reduced to the point where it is barely capable of eliciting a response. These procedures have direct implications for the treatment of PTSD and could be implemented in a virtual reality environment.

  4. Eyeblink classical conditioning and post-traumatic stress disorder - a model systems approach.

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    Schreurs, Bernard G; Burhans, Lauren B

    2015-01-01

    Not everyone exposed to trauma suffers flashbacks, bad dreams, numbing, fear, anxiety, sleeplessness, hyper-vigilance, hyperarousal, or an inability to cope, but those who do may suffer from post-traumatic stress disorder (PTSD). PTSD is a major physical and mental health problem for military personnel and civilians exposed to trauma. There is still debate about the incidence and prevalence of PTSD especially among the military, but for those who are diagnosed, behavioral therapy and drug treatment strategies have proven to be less than effective. A number of these treatment strategies are based on rodent fear conditioning research and are capable of treating only some of the symptoms because the extinction of fear does not deal with the various forms of hyper-vigilance and hyperarousal experienced by people with PTSD. To help address this problem, we have developed a preclinical eyeblink classical conditioning model of PTSD in which conditioning and hyperarousal can both be extinguished. We review this model and discuss findings showing that unpaired stimulus presentations can be effective in reducing levels of conditioning and hyperarousal even when unconditioned stimulus intensity is reduced to the point where it is barely capable of eliciting a response. These procedures have direct implications for the treatment of PTSD and could be implemented in a virtual reality environment.

  5. Enhanced Eyeblink Conditioning in Behaviorally Inhibited Individuals is Disrupted by Proactive Interference Following US Alone Pre-exposures.

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    Allen, Michael Todd; Miller, Daniel P

    2016-01-01

    Anxiety vulnerable individuals exhibit enhanced acquisition of conditioned eyeblinks as well as enhanced proactive interference from conditioned stimulus (CS) or unconditioned stimulus (US) alone pre-exposures (Holloway et al., 2012). US alone pre-exposures disrupt subsequent conditioned response (CR) acquisition to CS-US paired trials as compared to context pre-exposure controls. While Holloway et al. (2012) reported enhanced acquisition in high trait anxiety individuals in the context condition, anxiety vulnerability effects were not reported for the US alone pre-exposure group. It appears from the published data that there were no differences between high and low anxiety individuals in the US alone condition. In the work reported here, we sought to extend the findings of enhanced proactive interference with US alone pre-exposures to determine if the enhanced conditioning was disrupted by proactive interference procedures. We also were interested in the spontaneous eyeblinks during the pre-exposure phase of training. We categorized individuals as anxiety vulnerability or non-vulnerable individuals based scores on the Adult Measure of Behavioral Inhibition (AMBI). Sixty-six participants received 60 trials consisting of 30 US alone or context alone pre-exposures followed by 30 CS-US trials. US alone pre-exposures not only disrupted CR acquisition overall, but behaviorally inhibited (BI) individuals exhibited enhanced proactive interference as compared to non-inhibited (NI) individuals. In addition, US alone pre-exposures disrupted the enhanced acquisition observed in BI individuals as compared to NI individuals following context alone pre-exposures. Differences were also found in rates of spontaneous eyeblinks between BI and NI individuals during context pre-exposure. Our findings will be discussed in the light of the neural substrates of eyeblink conditioning as well as possible factors such as hypervigilance in the amygdala and hippocampal systems, and possible

  6. Eyeblink conditioning in unmedicated schizophrenia patients: a positron emission tomography study.

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    Parker, Krystal L; Andreasen, Nancy C; Liu, Dawei; Freeman, John H; O'Leary, Daniel S

    2013-12-30

    Previous studies suggest that patients with schizophrenia exhibit dysfunctions in a widely distributed circuit-the cortico-cerebellar-thalamic-cortical circuit, or CCTCC-and that this may explain the multiple cognitive deficits observed in the disorder. This study uses positron emission tomography (PET) with O(15) H₂O to measure regional cerebral blood flow (rCBF) in response to a classic test of cerebellar function, the associative learning that occurs during eyeblink conditioning, in a sample of 20 unmedicated schizophrenia patients and 20 closely matched healthy controls. The PET paradigm examined three phases of acquisition and extinction (early, middle and late). The patients displayed impaired behavioral performance during both acquisition and extinction. The imaging data indicate that, compared to the control subjects, the patients displayed decreases in rCBF in all three components of the CCTCC during both acquisition and extinction. Specifically, patients had less rCBF in the middle and medial frontal lobes, anterior cerebellar lobules I/V and VI, as well as the thalamus during acquisition and although similar areas were found in the frontal lobe, ipsilateral cerebellar lobule IX showed consistently less activity in patients during extinction. Thus this study provides additional support for the hypothesis that patients with schizophrenia have a cognitive dysmetria--an inability to smoothly coordinate many different types of mental activity--that affects even a very basic cognitive task that taps into associative learning. © 2013 Elsevier Ireland Ltd. All rights reserved.

  7. Deep cerebellar nuclei play an important role in two-tone discrimination on delay eyeblink conditioning in C57BL/6 mice.

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    Toshiro Sakamoto

    Full Text Available Previous studies have shown that deep cerebellar nuclei (DCN-lesioned mice develop conditioned responses (CR on delay eyeblink conditioning when a salient tone conditioned stimulus (CS is used, which suggests that the cerebellum potentially plays a role in more complicated cognitive functions. In the present study, we examined the role of DCN in tone frequency discrimination in the delay eyeblink-conditioning paradigm. In the first experiment, DCN-lesioned and sham-operated mice were subjected to standard simple eyeblink conditioning under low-frequency tone CS (LCS: 1 kHz, 80 dB or high-frequency tone CS (HCS: 10 kHz, 70 dB conditions. DCN-lesioned mice developed CR in both CS conditions as well as sham-operated mice. In the second experiment, DCN-lesioned and sham-operated mice were subjected to two-tone discrimination tasks, with LCS+ (or HCS+ paired with unconditioned stimulus (US, and HCS- (or LCS- without US. CR% in sham-operated mice increased in LCS+ (or HCS+ trials, regardless of tone frequency of CS, but not in HCS- (or LCS- trials. The results indicate that sham-operated mice can discriminate between LCS+ and HCS- (or HCS+ and LCS-. In contrast, DCN-lesioned mice showed high CR% in not only LCS+ (or HCS+ trials but also HCS- (or LCS- trials. The results indicate that DCN lesions impair the discrimination between tone frequency in eyeblink conditioning. Our results suggest that the cerebellum plays a pivotal role in the discrimination of tone frequency.

  8. Stimulation of the Lateral Geniculate, Superior Colliculus, or Visual Cortex is Sufficient for Eyeblink Conditioning in Rats

    Science.gov (United States)

    Halverson, Hunter E.; Hubbard, Erin M.; Freeman, John H.

    2009-01-01

    The role of the cerebellum in eyeblink conditioning is well established. Less work has been done to identify the necessary conditioned stimulus (CS) pathways that project sensory information to the cerebellum. A possible visual CS pathway has been hypothesized that consists of parallel inputs to the pontine nuclei from the lateral geniculate…

  9. Model-Driven Analysis of Eyeblink Classical Conditioning Reveals the Underlying Structure of Cerebellar Plasticity and Neuronal Activity.

    Science.gov (United States)

    Antonietti, Alberto; Casellato, Claudia; D'Angelo, Egidio; Pedrocchi, Alessandra

    The cerebellum plays a critical role in sensorimotor control. However, how the specific circuits and plastic mechanisms of the cerebellum are engaged in closed-loop processing is still unclear. We developed an artificial sensorimotor control system embedding a detailed spiking cerebellar microcircuit with three bidirectional plasticity sites. This proved able to reproduce a cerebellar-driven associative paradigm, the eyeblink classical conditioning (EBCC), in which a precise time relationship between an unconditioned stimulus (US) and a conditioned stimulus (CS) is established. We challenged the spiking model to fit an experimental data set from human subjects. Two subsequent sessions of EBCC acquisition and extinction were recorded and transcranial magnetic stimulation (TMS) was applied on the cerebellum to alter circuit function and plasticity. Evolutionary algorithms were used to find the near-optimal model parameters to reproduce the behaviors of subjects in the different sessions of the protocol. The main finding is that the optimized cerebellar model was able to learn to anticipate (predict) conditioned responses with accurate timing and success rate, demonstrating fast acquisition, memory stabilization, rapid extinction, and faster reacquisition as in EBCC in humans. The firing of Purkinje cells (PCs) and deep cerebellar nuclei (DCN) changed during learning under the control of synaptic plasticity, which evolved at different rates, with a faster acquisition in the cerebellar cortex than in DCN synapses. Eventually, a reduced PC activity released DCN discharge just after the CS, precisely anticipating the US and causing the eyeblink. Moreover, a specific alteration in cortical plasticity explained the EBCC changes induced by cerebellar TMS in humans. In this paper, for the first time, it is shown how closed-loop simulations, using detailed cerebellar microcircuit models, can be successfully used to fit real experimental data sets. Thus, the changes of the

  10. Harnessing the power of theta: natural manipulations of cognitive performance during hippocampal theta-contingent eyeblink conditioning

    Science.gov (United States)

    Hoffmann, Loren C.; Cicchese, Joseph J.; Berry, Stephen D.

    2015-01-01

    Neurobiological oscillations are regarded as essential to normal information processing, including coordination and timing of cells and assemblies within structures as well as in long feedback loops of distributed neural systems. The hippocampal theta rhythm is a 3–12 Hz oscillatory potential observed during cognitive processes ranging from spatial navigation to associative learning. The lower range, 3–7 Hz, can occur during immobility and depends upon the integrity of cholinergic forebrain systems. Several studies have shown that the amount of pre-training theta in the rabbit strongly predicts the acquisition rate of classical eyeblink conditioning and that impairment of this system substantially slows the rate of learning. Our lab has used a brain-computer interface (BCI) that delivers eyeblink conditioning trials contingent upon the explicit presence or absence of hippocampal theta. A behavioral benefit of theta-contingent training has been demonstrated in both delay and trace forms of the paradigm with a two- to four-fold increase in learning speed. This behavioral effect is accompanied by enhanced amplitude and synchrony of hippocampal local field potential (LFP)s, multi-unit excitation, and single-unit response patterns that depend on theta state. Additionally, training in the presence of hippocampal theta has led to increases in the salience of tone-induced unit firing patterns in the medial prefrontal cortex, followed by persistent multi-unit activity during the trace interval. In cerebellum, rhythmicity and precise synchrony of stimulus time-locked LFPs with those of hippocampus occur preferentially under the theta condition. Here we review these findings, integrate them into current models of hippocampal-dependent learning and suggest how improvement in our understanding of neurobiological oscillations is critical for theories of medial temporal lobe processes underlying intact and pathological learning. PMID:25918501

  11. Harnessing the power of theta: natural manipulations of cognitive performance during hippocampal theta-contingent eyeblink conditioning.

    Science.gov (United States)

    Hoffmann, Loren C; Cicchese, Joseph J; Berry, Stephen D

    2015-01-01

    Neurobiological oscillations are regarded as essential to normal information processing, including coordination and timing of cells and assemblies within structures as well as in long feedback loops of distributed neural systems. The hippocampal theta rhythm is a 3-12 Hz oscillatory potential observed during cognitive processes ranging from spatial navigation to associative learning. The lower range, 3-7 Hz, can occur during immobility and depends upon the integrity of cholinergic forebrain systems. Several studies have shown that the amount of pre-training theta in the rabbit strongly predicts the acquisition rate of classical eyeblink conditioning and that impairment of this system substantially slows the rate of learning. Our lab has used a brain-computer interface (BCI) that delivers eyeblink conditioning trials contingent upon the explicit presence or absence of hippocampal theta. A behavioral benefit of theta-contingent training has been demonstrated in both delay and trace forms of the paradigm with a two- to four-fold increase in learning speed. This behavioral effect is accompanied by enhanced amplitude and synchrony of hippocampal local field potential (LFP)s, multi-unit excitation, and single-unit response patterns that depend on theta state. Additionally, training in the presence of hippocampal theta has led to increases in the salience of tone-induced unit firing patterns in the medial prefrontal cortex, followed by persistent multi-unit activity during the trace interval. In cerebellum, rhythmicity and precise synchrony of stimulus time-locked LFPs with those of hippocampus occur preferentially under the theta condition. Here we review these findings, integrate them into current models of hippocampal-dependent learning and suggest how improvement in our understanding of neurobiological oscillations is critical for theories of medial temporal lobe processes underlying intact and pathological learning.

  12. The distressed (Type D) personality factor of social inhibition, but not negative affectivity, enhances eyeblink conditioning.

    Science.gov (United States)

    Allen, M T; Handy, J D; Blankenship, M R; Servatius, R J

    2018-06-01

    Recent work has focused on a learning diathesis model in which specific personality factors such as behavioral inhibition (BI) may influence associative learning and in turn increase risk for the development of anxiety disorders. We have found in a series of studies that individuals self-reporting high levels of BI exhibit enhanced acquisition of conditioned eyeblinks. In the study reported here, hypotheses were extended to include distressed (Type D) personality which has been found to be related to BI. Type D personality is measured with the DS-14 scale which includes two subscales measuring negative affectivity (NA) and social inhibition (SI). We hypothesized that SI, which is similar to BI, would result in enhanced acquisition while the effect of NA is unclear. Eighty nine participants completed personality inventories including the Adult Measure of Behavioral Inhibition (AMBI) and DS-14. All participants received 60 acquisition trials with a 500 ms, 1000 Hz, tone CS and a co-terminating 50 ms, 5 psi corneal airpuff US. Participants received either 100% CS-US paired trials or a schedule of partial reinforcement where 50% US alone trials were intermixed into CS-US training. Acquisition of CRs did not differ between the two training protocols. Whereas BI was significantly related to Type D, SI, and NA, only BI and SI individuals exhibited enhanced acquisition of conditioned eyeblinks as compared to non-inhibited individuals. Personality factors now including social inhibition can be used to identify individuals who express enhanced associative learning which lends further support to a learning diathesis model of anxiety disorders. Copyright © 2018 Elsevier B.V. All rights reserved.

  13. Enhanced eyeblink conditioning in behaviorally inhibited individuals is disrupted by proactive interference following US alone pre-exposures.

    Directory of Open Access Journals (Sweden)

    Michael Todd Allen

    2016-03-01

    Full Text Available Anxiety vulnerable individuals exhibit enhanced acquisition of conditioned eyeblinks as well as enhanced proactive interference from CS or US alone pre-exposures (Holloway et al., 2012. US alone pre-exposures disrupt subsequent CR acquisition to CS-US paired trials as compared to context pre-exposure controls. While Holloway et al., (2012 reported enhanced acquisition in high trait anxiety individuals in the context condition, anxiety vulnerability effects were not reported for the US alone pre-exposure group. It appears from the published data that there were no differences between high and low anxiety individuals in the US alone condition. In the work reported here, we sought to extend the findings of enhanced proactive interference with US alone pre-exposures to determine if the enhanced conditioning was disrupted by proactive interference procedures. We also were interested in the spontaneous eyeblinks during the pre-exposure phase of training. We categorized individuals as anxiety vulnerability or non-vulnerable individuals based scores on the Adult Measure of Behavioural Inhibition (AMBI. Sixty six participants received 60 trials consisting of 30 US alone or context alone pre-exposures followed by 30 CS-US trials. US alone pre-exposures not only disrupted CR acquisition overall, but behaviorally inhibited (BI individuals exhibited enhanced proactive interference as compared to non-inhibited (NI individuals. In addition, US alone pre-exposures disrupted the enhanced acquisition observed in BI individuals as compared to NI individuals following context alone pre-exposures. Differences were also found in rates of spontaneous eyeblinks between BI and NI individuals during context pre-exposure. Our findings will be discussed in the light of the neural substrates of eyeblink conditioning as well as possible factors such as hypervigilance in the amygdala and hippocampal systems, and possible learned helplessness. Applications of these findings of

  14. The time course of face processing: startle eyeblink response modulation by face gender and expression.

    Science.gov (United States)

    Duval, Elizabeth R; Lovelace, Christopher T; Aarant, Justin; Filion, Diane L

    2013-12-01

    The purpose of this study was to investigate the effects of both facial expression and face gender on startle eyeblink response patterns at varying lead intervals (300, 800, and 3500ms) indicative of attentional and emotional processes. We aimed to determine whether responses to affective faces map onto the Defense Cascade Model (Lang et al., 1997) to better understand the stages of processing during affective face viewing. At 300ms, there was an interaction between face expression and face gender with female happy and neutral faces and male angry faces producing inhibited startle. At 3500ms, there was a trend for facilitated startle during angry compared to neutral faces. These findings suggest that affective expressions are perceived differently in male and female faces, especially at short lead intervals. Future studies investigating face processing should take both face gender and expression into account. © 2013.

  15. Unilateral lateral entorhinal inactivation impairs memory expression in trace eyeblink conditioning.

    Directory of Open Access Journals (Sweden)

    Stephanie E Tanninen

    Full Text Available Memory in trace eyeblink conditioning is mediated by an inter-connected network that involves the hippocampus (HPC, several neocortical regions, and the cerebellum. This network reorganizes after learning as the center of the network shifts from the HPC to the medial prefrontal cortex (mPFC. Despite the network reorganization, the lateral entorhinal cortex (LEC plays a stable role in expressing recently acquired HPC-dependent memory as well as remotely acquired mPFC-dependent memory. Entorhinal involvement in recent memory expression may be attributed to its previously proposed interactions with the HPC. In contrast, it remains unknown how the LEC participates in memory expression after the network disengages from the HPC. The present study tested the possibility that the LEC and mPFC functionally interact during remote memory expression by examining the impact of pharmacological inactivation of the LEC in one hemisphere and the mPFC in the contralateral hemisphere on memory expression in rats. Memory expression one day and one month after learning was significantly impaired after LEC-mPFC inactivation; however, the degree of impairment was comparable to that after unilateral LEC inactivation. Unilateral mPFC inactivation had no effect on recent or remote memory expression. These results suggest that the integrity of the LEC in both hemispheres is necessary for memory expression. Functional interactions between the LEC and mPFC should therefore be tested with an alternative design.

  16. Effects of anxiety sensitivity and expectations on the modulation of the startle eyeblink response during a caffeine challenge.

    Science.gov (United States)

    Benke, Christoph; Blumenthal, Terry D; Modeß, Christiane; Hamm, Alfons O; Pané-Farré, Christiane A

    2015-09-01

    The way in which the tendency to fear somatic arousal sensations (anxiety sensitivity), in interaction with the created expectations regarding arousal induction, might affect defensive responding to a symptom provocation challenge is not yet understood. The present study investigated the effect of anxiety sensitivity on autonomic arousal, startle eyeblink responses, and reported arousal and alertness to expected vs. unexpected caffeine consumption. To create a match/mismatch of expected and experienced arousal, high and low anxiety sensitive participants received caffeine vs. no drug either mixed in coffee (expectation of arousal induction) or in bitter lemon soda (no expectation of arousal induction) on four separate occasions. Autonomic arousal (heart rate, skin conductance level), respiration (end-tidal CO2, minute ventilation), defensive reflex responses (startle eyeblink), and reported arousal and alertness were recorded prior to, immediately and 30 min after beverage ingestion. Caffeine increased ventilation, autonomic arousal, and startle response magnitudes. Both groups showed comparable levels of autonomic and respiratory responses. The startle eyeblink responses were decreased when caffeine-induced arousal occurred unexpectedly, e.g., after administering caffeine in bitter lemon. This effect was more accentuated in high anxiety sensitive persons. Moreover, in high anxiety sensitive persons, the expectation of arousal (coffee consumption) led to higher subjective alertness when administering caffeine and increased arousal even if no drug was consumed. Unexpected symptom provocation leads to increased attention allocation toward feared arousal sensations in high anxiety sensitive persons. This finding broadens our understanding of modulatory mechanisms in defensive responding to bodily symptoms.

  17. Effects of OEF/OIF-Related Physical and Emotional Co-Morbidities on Associative Learning: Concurrent Delay and Trace Eyeblink Classical Conditioning

    Directory of Open Access Journals (Sweden)

    Regina E. McGlinchey

    2014-03-01

    Full Text Available This study examined the performance of veterans and active duty personnel who served in Operation Enduring Freedom and/or Operation Iraqi Freedom (OEF/OIF on a basic associative learning task. Eighty-eight individuals participated in this study. All received a comprehensive clinical evaluation to determine the presence and severity of posttraumatic stress disorder (PTSD and traumatic brain injury (TBI. The eyeblink conditioning task was composed of randomly intermixed delay and trace conditioned stimulus (CS and unconditioned stimulus (US pairs (acquisition followed by a series of CS only trials (extinction. Results revealed that those with a clinical diagnosis of PTSD or a diagnosis of PTSD with comorbid mTBI acquired delay and trace conditioned responses (CRs to levels and at rates similar to a deployed control group, thus suggesting intact basic associative learning. Differential extinction impairment was observed in the two clinical groups. Acquisition of CRs for both delay and trace conditioning, as well as extinction of trace CRs, was associated with alcoholic behavior across all participants. These findings help characterize the learning and memory function of individuals with PTSD and mTBI from OEF/OIF and raise the alarming possibility that the use of alcohol in this group may lead to more significant cognitive dysfunction.

  18. New insights into the nature of cerebellar-dependent eyeblink conditioning deficits in schizophrenia: A hierarchical linear modeling approach

    Directory of Open Access Journals (Sweden)

    Amanda R Bolbecker

    2016-01-01

    Full Text Available Evidence of cerebellar dysfunction in schizophrenia has mounted over the past several decades, emerging from neuroimaging, neuropathological, and behavioral studies. Consistent with these findings, cerebellar-dependent delay eyeblink conditioning (dEBC deficits have been identified in schizophrenia. While repeated measures analysis of variance (ANOVA is traditionally used to analyze dEBC data, hierarchical linear modeling (HLM more reliably describes change over time by accounting for the dependence in repeated measures data. This analysis approach is well suited to dEBC data analysis because it has less restrictive assumptions and allows unequal variances. The current study examined dEBC measured with electromyography in a single-cue tone paradigm in an age-matched sample of schizophrenia participants and healthy controls (N=56 per group using HLM. Subjects participated in 90 trials (10 blocks of dEBC, during which a 400 ms tone co-terminated with a 50 ms air puff delivered to the left eye. Each block also contained 1 tone-alone trial. The resulting block averages of dEBC data were fitted to a 3-parameter logistic model in HLM, revealing significant differences between schizophrenia and control groups on asymptote and inflection point, but not slope. These findings suggest that while the learning rate is not significantly different compared to controls, associative learning begins to level off later and a lower ultimate level of associative learning is achieved in schizophrenia. Given the large sample size in the present study, HLM may provide a more nuanced and definitive analysis of differences between schizophrenia and controls on dEBC.

  19. Voluntary eyeblinks disrupt iconic memory.

    Science.gov (United States)

    Thomas, Laura E; Irwin, David E

    2006-04-01

    In the present research, we investigated whether eyeblinks interfere with cognitive processing. In Experiment 1, the participants performed a partial-report iconic memory task in which a letter array was presented for 106 msec, followed 50, 150, or 750 msec later by a tone that cued recall of onerow of the array. At a cue delay of 50 msec between array offset and cue onset, letter report accuracy was lower when the participants blinked following array presentation than under no-blink conditions; the participants made more mislocation errors under blink conditions. This result suggests that blinking interferes with the binding of object identity and object position in iconic memory. Experiment 2 demonstrated that interference due to blinks was not due merely to changes in light intensity. Experiments 3 and 4 demonstrated that other motor responses did not interfere with iconic memory. We propose a new phenomenon, cognitive blink suppression, in which blinking inhibits cognitive processing. This phenomenon may be due to neural interference. Blinks reduce activation in area V1, which may interfere with the representation of information in iconic memory.

  20. Effect of emotional picture viewing on voluntary eyeblinks.

    Directory of Open Access Journals (Sweden)

    Suvi Karla

    Full Text Available Eyeblinks, whether reflexive or voluntary, play an important role in protecting our vision. When viewing pictures, reflexive eyeblinks are known to be modulated by the emotional state induced thereby. More specifically, the hedonic valence (unpleasantness-pleasantness induced by the picture has been shown to have a linear relationship with the amplitude of a startle blink elicited during picture viewing. This effect has been attributed to congruence between an ongoing state and task demands: an unpleasant emotional state is assumed to bias our attention towards potentially harmful stimuli, such as startle tones. However, recent research suggests that the valence-specific modulation may not be limited to the sensory parts of the reflexive pathway related to startle responses. Here, we examined the effect of emotional picture viewing on voluntary (in response to a written command eyeblinks in adult humans. Emotional modulation of startle blinks was also evaluated. We found that when viewing unpleasant pictures, the amplitude of reflexive eyeblinks was augmented, but the amplitude of voluntary eyeblinks was unaffected. Nevertheless, the response latencies of voluntary eyeblinks were found to be delayed during the viewing of pleasant and unpleasant relative to neutral pictures. We conclude that these results support the theory that emotional experience augments sensory processing specific to potentially harmful stimuli. Further, the emotional state seems not to exert an effect on voluntarily elicited motor activity.

  1. Monitoring kinetic and frequency-domain properties of eyelid responses in mice with magnetic distance measurement technique

    NARCIS (Netherlands)

    W.L. den Ouden; G. Perry; S.M. Highstein; C.I. de Zeeuw (Chris); S.K.E. Koekkoek (Bas)

    2002-01-01

    textabstractClassical eye-blink conditioning in mutant mice can be used to study the molecular mechanisms underlying associative learning. To measure the kinetic and frequency domain properties of conditioned (tone - periorbital shock procedure) and unconditioned eyelid responses

  2. Lack of connexin43-mediated Bergmann glial gap junctional coupling does not affect cerebellar long-term depression, motor coordination, or eyeblink conditioning

    Directory of Open Access Journals (Sweden)

    Mika Tanaka

    2008-04-01

    Full Text Available Bergmann glial cells are specialized astrocytes in the cerebellum. In the mature cerebellar molecular layer, Bergmann glial processes are closely associated with Purkinje cells, enclosing Purkinje cell dendritic synapses with a glial sheath. There is intensive gap junctional coupling between Bergmann glial processes, but their significance in cerebellar functions is not known. Connexin43 (Cx43, a major component of astrocytic gap junction channels, is abundantly expressed in Bergmann glial cells. To examine the role of Cx43-mediated gap junctions between Bergmann glial cells in cerebellar functions, we generated Cx43 conditional knockout mice with the S100b-Cre transgenic line (Cx43fl/fl:S100b-Cre, which exhibited a significant loss of Cx43 in the Bergmann glial cells and astrocytes in the cerebellum with a postnatal onset. The Cx43fl/fl:S100b-Cre mice had normal cerebellar architecture. Although gap junctional coupling between the Bergmann glial cells measured by spreading of microinjected Lucifer yellow was virtually abolished in Cx43fl/fl:S100b-Cre mice, electrophysiologic analysis revealed that cerebellar long-term depression could be induced and maintained normally in thier cerebellar slices. In addition, at the behavioral level, Cx43fl/fl:S100b-Cre mice had normal motor coordination in the rotarod task and normal conditioned eyelid response. Our findings suggest that Cx43-mediated gap junctional coupling between Bergmann glial cells is not necessary for the neuron-glia interactions required for cerebellum-dependent motor coordination and motor learning.

  3. Eyeblink Synchrony in Multimodal Human-Android Interaction.

    Science.gov (United States)

    Tatsukawa, Kyohei; Nakano, Tamami; Ishiguro, Hiroshi; Yoshikawa, Yuichiro

    2016-12-23

    As the result of recent progress in technology of communication robot, robots are becoming an important social partner for humans. Behavioral synchrony is understood as an important factor in establishing good human-robot relationships. In this study, we hypothesized that biasing a human's attitude toward a robot changes the degree of synchrony between human and robot. We first examined whether eyeblinks were synchronized between a human and an android in face-to-face interaction and found that human listeners' eyeblinks were entrained to android speakers' eyeblinks. This eyeblink synchrony disappeared when the android speaker spoke while looking away from the human listeners but was enhanced when the human participants listened to the speaking android while touching the android's hand. These results suggest that eyeblink synchrony reflects a qualitative state in human-robot interactions.

  4. Time Course of the Rabbit's Conditioned Nictitating Membrane Movements during Acquisition, Extinction, and Reacquisition

    Science.gov (United States)

    Kehoe, E. James; Ludvig, Elliot A.; Sutton, Richard S.

    2014-01-01

    The present experiment tested whether or not the time course of a conditioned eyeblink response, particularly its duration, would expand and contract, as the magnitude of the conditioned response (CR) changed massively during acquisition, extinction, and reacquisition. The CR duration remained largely constant throughout the experiment, while CR…

  5. Distributed Dynamic Condition Response Structures

    DEFF Research Database (Denmark)

    Hildebrandt, Thomas; Mukkamala, Raghava Rao

    We present distributed dynamic condition response structures as a declarative process model inspired by the workflow language employed by our industrial partner and conservatively generalizing labelled event structures. The model adds to event structures the possibility to 1) finitely specify...... as a labelled transition system. Exploration of the relationship between dynamic condition response structures and traditional models for concurrency, application to more complex scenarios, and further extensions of the model is left to future work....

  6. Nested Dynamic Condition Response Graphs

    DEFF Research Database (Denmark)

    Hildebrandt, Thomas; Mukkamala, Raghava Rao; Slaats, Tijs

    2012-01-01

    We present an extension of the recently introduced declarative process model Dynamic Condition Response Graphs ( DCR Graphs) to allow nested subgraphs and a new milestone relation between events. The extension was developed during a case study carried out jointly with our industrial partner...

  7. Effects of meditation practice on spontaneous eyeblink rate.

    Science.gov (United States)

    Kruis, Ayla; Slagter, Heleen A; Bachhuber, David R W; Davidson, Richard J; Lutz, Antoine

    2016-05-01

    A rapidly growing body of research suggests that meditation can change brain and cognitive functioning. Yet little is known about the neurochemical mechanisms underlying meditation-related changes in cognition. Here, we investigated the effects of meditation on spontaneous eyeblink rates (sEBR), a noninvasive peripheral correlate of striatal dopamine activity. Previous studies have shown a relationship between sEBR and cognitive functions such as mind wandering, cognitive flexibility, and attention-functions that are also affected by meditation. We therefore expected that long-term meditation practice would alter eyeblink activity. To test this, we recorded baseline sEBR and intereyeblink intervals (IEBI) in long-term meditators (LTM) and meditation-naive participants (MNP). We found that LTM not only blinked less frequently, but also showed a different eyeblink pattern than MNP. This pattern had good to high degree of consistency over three time points. Moreover, we examined the effects of an 8-week course of mindfulness-based stress reduction on sEBR and IEBI, compared to an active control group and a waitlist control group. No effect of short-term meditation practice was found. Finally, we investigated whether different types of meditation differentially alter eyeblink activity by measuring sEBR and IEBI after a full day of two kinds of meditation practices in the LTM. No effect of meditation type was found. Taken together, these findings may suggest either that individual difference in dopaminergic neurotransmission is a self-selection factor for meditation practice, or that long-term, but not short-term meditation practice induces stable changes in baseline striatal dopaminergic functioning. © 2016 Society for Psychophysiological Research.

  8. Spontaneous Eye-Blinking and Stereotyped Behavior in Older Persons with Mental Retardation

    Science.gov (United States)

    Roebel, Amanda M.; MacLean, William E., Jr.

    2007-01-01

    Previous research indicates that abnormal stereotyped movements are associated with central dopamine dysfunction and that eye-blink rate is a noninvasive, in vivo measure of dopamine function. We measured the spontaneous eye-blinking and stereotyped behavior of older adults with severe/profound mental retardation living in a state mental…

  9. Microbial Response to Spaceflight Conditions

    OpenAIRE

    Moeller, R.

    2017-01-01

    Space radiation, including Galactic Cosmic Rays (GCR) and Solar Particle Events (SPE), represents a major hazard for biological systems beyond Earth. Spores of Bacillus subtilis have been shown to be suitable dosimeters for probing extreme terrestrial and extraterrestrial environmental conditions in astrobiological and environmental studies. During dormancy spores are metabolically inactive; thus substantial DNA, protein, tRNA and ribosome damage can accumulate while the spo...

  10. Performance in eyeblink conditioning is age and sex dependent

    NARCIS (Netherlands)

    Löwgren, Karolina; Bååth, Rasmus; Rasmussen, Anders; Boele, Henk-Jan; Koekkoek, Sebastiaan K E; De Zeeuw, Chris I; Hesslow, Germund

    2017-01-01

    A growing body of evidence suggests that the cerebellum is involved in both cognition and language. Abnormal cerebellar development may contribute to neurodevelopmental disorders such as attention deficit hyperactivity disorder (ADHD), autism, fetal alcohol syndrome, dyslexia, and specific language

  11. Performance in eyeblink conditioning is age and sex dependent

    NARCIS (Netherlands)

    Löwgren, K. (Karolina); Bååth, R. (Rasmus); A. Rasmussen (Anders); H.J. Boele (Henk-Jan); S.K.E. Koekkoek (Bas); C.I. de Zeeuw (Chris); Hesslow, G. (Germund)

    2017-01-01

    textabstractA growing body of evidence suggests that the cerebellum is involved in both cognition and language. Abnormal cerebellar development may contribute to neurodevelopmental disorders such as attention deficit hyperactivity disorder (ADHD), autism, fetal alcohol syndrome, dyslexia, and

  12. Pre-pulse inhibition of the acoustic startle eye-blink in the Göttingen minipig

    DEFF Research Database (Denmark)

    Arnfred, S. M.; Lind, N. M.; Hansen, A. K.

    2004-01-01

    Pre-pulse inhibition (PPI) of the startle response is a measure of sensorimotor gating which has been frequently shown to be deficient in schizophrenic patients. In humans it is typically measured as the attenuation of the startle eye-blink reflex EMG when a startle eliciting noise is preceded...... by a weak white noise pre-pulse (PP), the interval between the PP and the startle noise stimulus (SNS) determining the degree of inhibition. Aiming at developing a new animal model of schizophrenia, we have investigated the acoustic startle eye-blink and PPI in 10 Göttingen minipigs. The stimuli......, and three other pigs did not have a startle response of a sufficient magnitude to demonstrate the PPI seen in the other six pigs at the expected PP intervals of 60, 120, and 220 ms. Maximal inhibition was seen at the 220 ms interval (mean PPI 58.6%, range -18.4 to 94.6%, N = 9). Most of the results...

  13. Startling sweet temptations: hedonic chocolate deprivation modulates experience, eating behavior, and eyeblink startle.

    Science.gov (United States)

    Blechert, Jens; Naumann, Eva; Schmitz, Julian; Herbert, Beate M; Tuschen-Caffier, Brunna

    2014-01-01

    Many individuals restrict their food intake to prevent weight gain. This restriction has both homeostatic and hedonic effects but their relative contribution is currently unclear. To isolate hedonic effects of food restriction, we exposed regular chocolate eaters to one week of chocolate deprivation but otherwise regular eating. Before and after this hedonic deprivation, participants viewed images of chocolate and images of high-calorie but non-chocolate containing foods, while experiential, behavioral and eyeblink startle responses were measured. Compared to satiety, hedonic deprivation triggered increased chocolate wanting, liking, and chocolate consumption but also feelings of frustration and startle potentiation during the intertrial intervals. Deprivation was further characterized by startle inhibition during both chocolate and food images relative to the intertrial intervals. Individuals who responded with frustration to the manipulation and those who scored high on a questionnaire of impulsivity showed more relative startle inhibition. The results reveal the profound effects of hedonic deprivation on experiential, behavioral and attentional/appetitive response systems and underscore the role of individual differences and state variables for startle modulation. Implications for dieting research and practice as well as for eating and weight disorders are discussed.

  14. Step response and frequency response of an air conditioning system

    NARCIS (Netherlands)

    Crommelin, R.D.; Jackman, P.J.

    1978-01-01

    A system of induction units of an existing air conditioning system has been analyzed with respect to its dynamic properties. Time constants were calculated and measured by analogue models. Comparison with measurements at the installation itself showed a reasonable agreement. Frequency responses were

  15. Emotionally Excited Eyeblink-Rate Variability Predicts an Experience of Transportation into the Narrative World

    Directory of Open Access Journals (Sweden)

    Ryota eNomura

    2015-04-01

    Full Text Available Collective spectator communications such as oral presentations, movies, and storytelling performances are ubiquitous in human culture. This study investigated the effects of past viewing experiences and differences in expressive performance on an audience’s transportive experience into a created world of a storytelling performance. In the experiment, 60 participants (mean age = 34.12 yrs., SD = 13.18 yrs., range 18–63 yrs. were assigned to watch one of two videotaped performances that were played (1 in an orthodox way for frequent viewers and (2 in a modified way aimed at easier comprehension for first-time viewers. Eyeblink synchronization among participants was quantified by employing distance-based measurements of spike trains, Dspike and Dinterval (Victor & Purpura, 1997. The results indicated that even non-familiar participants’ eyeblinks were synchronized as the story progressed and that the effect of the viewing experience on transportation was weak. Rather, the results of a multiple regression analysis demonstrated that the degrees of transportation could be predicted by a retrospectively reported humor experience and higher real-time variability (i.e., logarithmic transformed standard deviation of inter blink intervals during a performance viewing. The results are discussed from the viewpoint in which the extent of eyeblink synchronization and eyeblink-rate variability acts as an index of the inner experience of audience members.

  16. Affective Modulation of the Startle Eyeblink and Postauricular Reflexes in Autism Spectrum Disorder

    Science.gov (United States)

    Dichter, Gabriel S.; Benning, Stephen D.; Holtzclaw, Tia N.; Bodfish, James W.

    2010-01-01

    Eyeblink and postauricular reflexes to standardized affective images were examined in individuals without (n = 37) and with (n = 20) autism spectrum disorders (ASDs). Affective reflex modulation in control participants replicated previous findings. The ASD group, however, showed anomalous reflex modulation patterns, despite similar self-report…

  17. Can bread processing conditions alter glycaemic response?

    Science.gov (United States)

    Lau, Evelyn; Soong, Yean Yean; Zhou, Weibiao; Henry, Jeyakumar

    2015-04-15

    Bread is a staple food that is traditionally made from wheat flour. This study aimed to compare the starch digestibility of western baked bread and oriental steamed bread. Four types of bread were prepared: western baked bread (WBB) and oriental steamed bread (OSB), modified baked bread (MBB) made with the OSB recipe and WBB processing, and modified steamed bread (MSB) made with the WBB recipe and OSB processing. MBB showed the highest starch digestibility in vitro, followed by WBB, OSB and MSB. A similar trend was observed for glycaemic response in vivo. MBB, WBB, OSB and MSB had a glycaemic index of 75±4, 71±5, 68±5 and 65±4, respectively. Processing differences had a more pronounced effect on starch digestibility in bread, and steamed bread was healthier in terms of glycaemic response. The manipulation of processing conditions could be an innovative route to alter the glycaemic response of carbohydrate-rich foods. Copyright © 2014 Elsevier Ltd. All rights reserved.

  18. Effects of transient blur and VDT screen luminance changes on eyeblink rate.

    Science.gov (United States)

    Cardona, Genís; Gómez, Marcelo; Quevedo, Lluïsa; Gispets, Joan

    2014-10-01

    A study was designed to evaluate the efficacy of three different strategies aiming at increasing spontaneous eyeblink rate (SEBR) during computer use. A total of 12 subjects (5 female) with a mean age of 28.7 years were instructed to read a text presented on a computer display terminal during 15min. Four reading sessions (reference and three "blinking events" [BE]) were programmed in which SEBR was digitally recorded. "Blinking events" were based on either a slight distortion of the text characters or on the presentation of a white screen instead of the text, with or without accompanying blinking instructions. All BE had a duration of 20ms and occurred every 15s. Participants graded the intrusiveness of each BE configuration, and the number of lines participants read in each session was recorded. Data from 11 subjects was analysed. A statistically significant difference in SEBR was encountered between the experimental configuration consisting on a white screen plus blinking instructions (7.8 blinks/min) and both reference (5.2 blinks/min; p=0.049) and white screen without blinking instructions (4.8 blinks/min; p=0.038). All three BE had superior levels of intrusiveness than reference conditions, although the performance of participants (line count) was not compromised. The joint contribution of white screen and blinking instructions has been shown to result in a short term improvement in blinking rate in the present sample of non-dry eye computer users. Further work is necessary to improve the acceptance of any BE aiming at influencing SEBR. Copyright © 2014 British Contact Lens Association. Published by Elsevier Ltd. All rights reserved.

  19. Eyeblink rate watching classical Hollywood and post-classical MTV editing styles, in media and non-media professionals.

    Science.gov (United States)

    Andreu-Sánchez, Celia; Martín-Pascual, Miguel Ángel; Gruart, Agnès; Delgado-García, José María

    2017-02-21

    While movie edition creates a discontinuity in audio-visual works for narrative and economy-of-storytelling reasons, eyeblink creates a discontinuity in visual perception for protective and cognitive reasons. We were interested in analyzing eyeblink rate linked to cinematographic edition styles. We created three video stimuli with different editing styles and analyzed spontaneous blink rate in participants (N = 40). We were also interested in looking for different perceptive patterns in blink rate related to media professionalization. For that, of our participants, half (n = 20) were media professionals, and the other half were not. According to our results, MTV editing style inhibits eyeblinks more than Hollywood style and one-shot style. More interestingly, we obtained differences in visual perception related to media professionalization: we found that media professionals inhibit eyeblink rate substantially compared with non-media professionals, in any style of audio-visual edition.

  20. Hippocampal-dependent Pavlovian conditioning in adult rats exposed to binge-like doses of ethanol as neonates.

    Science.gov (United States)

    Lindquist, Derick H

    2013-04-01

    Binge-like postnatal ethanol exposure produces significant damage throughout the brain in rats, including the cerebellum and hippocampus. In the current study, cue- and context-mediated Pavlovian conditioning were assessed in adult rats exposed to moderately low (3E; 3g/kg/day) or high (5E; 5g/kg/day) doses of ethanol across postnatal days 4-9. Ethanol-exposed and control groups were presented with 8 sessions of trace eyeblink conditioning followed by another 8 sessions of delay eyeblink conditioning, with an altered context presented over the last two sessions. Both forms of conditioning rely on the brainstem and cerebellum, while the more difficult trace conditioning also requires the hippocampus. The hippocampus is also needed to gate or modulate expression of the eyeblink conditioned response (CR) based on contextual cues. Results indicate that the ethanol-exposed rats were not significantly impaired in trace EBC relative to control subjects. In terms of CR topography, peak amplitude was significantly reduced by both doses of alcohol, whereas onset latency but not peak latency was significantly lengthened in the 5E rats across the latter half of delay EBC in the original training context. Neither dosage resulted in significant impairment in the contextual gating of the behavioral response, as revealed by similar decreases in CR production across all four treatment groups following introduction of the novel context. Results suggest ethanol-induced brainstem-cerebellar damage can account for the present results, independent of the putative disruption in hippocampal development and function proposed to occur following postnatal ethanol exposure. Copyright © 2013 Elsevier B.V. All rights reserved.

  1. Response moderation models for conditional dependence between response time and response accuracy.

    Science.gov (United States)

    Bolsinova, Maria; Tijmstra, Jesper; Molenaar, Dylan

    2017-05-01

    It is becoming more feasible and common to register response times in the application of psychometric tests. Researchers thus have the opportunity to jointly model response accuracy and response time, which provides users with more relevant information. The most common choice is to use the hierarchical model (van der Linden, 2007, Psychometrika, 72, 287), which assumes conditional independence between response time and accuracy, given a person's speed and ability. However, this assumption may be violated in practice if, for example, persons vary their speed or differ in their response strategies, leading to conditional dependence between response time and accuracy and confounding measurement. We propose six nested hierarchical models for response time and accuracy that allow for conditional dependence, and discuss their relationship to existing models. Unlike existing approaches, the proposed hierarchical models allow for various forms of conditional dependence in the model and allow the effect of continuous residual response time on response accuracy to be item-specific, person-specific, or both. Estimation procedures for the models are proposed, as well as two information criteria that can be used for model selection. Parameter recovery and usefulness of the information criteria are investigated using simulation, indicating that the procedure works well and is likely to select the appropriate model. Two empirical applications are discussed to illustrate the different types of conditional dependence that may occur in practice and how these can be captured using the proposed hierarchical models. © 2016 The British Psychological Society.

  2. Manipulating affective state influences conditioned appetitive responses.

    Science.gov (United States)

    Arnaudova, Inna; Krypotos, Angelos-Miltiadis; Effting, Marieke; Kindt, Merel; Beckers, Tom

    2017-10-06

    Affective states influence how individuals process information and behave. Some theories predict emotional congruency effects (e.g. preferential processing of negative information in negative affective states). Emotional congruency should theoretically obstruct the learning of reward associations (appetitive learning) and their ability to guide behaviour under negative mood. Two studies tested the effects of the induction of a negative affective state on appetitive Pavlovian learning, in which neutral stimuli were associated with chocolate (Experiment 1) or alcohol (Experiment 2) rewards. In both experiments, participants showed enhanced approach tendencies towards predictors of reward after a negative relative to a positive performance feedback manipulation. This increase was related to a reduction in positive affect in Experiment 1 only. No effects of the manipulation on conditioned reward expectancies, craving, or consumption were observed. Overall, our findings support the idea of counter-regulation, rather than emotional congruency effects. Negative affective states might therefore serve as a vulnerability factor for addiction, through increasing conditioned approach tendencies.

  3. Modelling cladding response to changing conditions

    Energy Technology Data Exchange (ETDEWEB)

    Tulkki, Ville; Ikonen, Timo [VTT Technical Research Centre of Finland ltd (Finland)

    2016-11-15

    The cladding of the nuclear fuel is subjected to varying conditions during fuel reactor life. Load drops and reversals can be modelled by taking cladding viscoelastic behaviour into account. Viscoelastic contribution to the deformation of metals is usually considered small enough to be ignored, and in many applications it merely contributes to the primary part of the creep curve. With nuclear fuel cladding the high temperature and irradiation as well as the need to analyse the variable load all emphasise the need to also inspect the viscoelasticity of the cladding.

  4. Governing conditions of repeatable Barkhausen noise response

    International Nuclear Information System (INIS)

    Stupakov, O.; Pal'a, J.; Takagi, T.; Uchimoto, T.

    2009-01-01

    The paper is devoted to the establishment of experimental conditions, which ensure the repeatability of magnetic Barkhausen noise testing in practice. For this task, the measurements were performed on open flat samples using different experimental configurations, including: different magnetization frequencies, sampling rates, and filter cut-off frequencies; using a sample-wrapped coil and using attached pick-up coils of various dimensions, with different lift-offs of a single yoke magnet and of the attached coil. The sample magnetization was controlled by a vertical array of three Hall sensors; their readings were extrapolated to the sample surface to precisely define its field. After analysis of the results, a scheme for an optimized sensor with a controlled field waveform was suggested to improve the measurement repeatability. The important issues of signal processing and parameter applicability were also discussed in detail.

  5. Pavlovian conditioning of multiple opioid-like responses in mice

    OpenAIRE

    Bryant, Camron D.; Roberts, Kristofer W.; Culbertson, Christopher S.; Le, Alan; Evans, Christopher J.; Fanselow, Michael S.

    2009-01-01

    Conditional responses in rodents such as locomotion have been reported for drugs of abuse and similar to the placebo response in humans, may be associated with the expectation of reward. We examined several conditional opioid-like responses and the influence of drug expectation on conditioned place preference and concomitant conditional locomotion. Male C57BL/6J mice were conditioned with the selective mu opioid receptor agonist fentanyl (0.2 mg/kg, i.p.) in a novel context and subsequently g...

  6. Pavlovian conditioning of multiple opioid-like responses in mice.

    Science.gov (United States)

    Bryant, Camron D; Roberts, Kristofer W; Culbertson, Christopher S; Le, Alan; Evans, Christopher J; Fanselow, Michael S

    2009-07-01

    Conditional responses in rodents such as locomotion have been reported for drugs of abuse and similar to the placebo response in humans, may be associated with the expectation of reward. We examined several conditional opioid-like responses and the influence of drug expectation on conditioned place preference and concomitant conditional locomotion. Male C57BL/6J mice were conditioned with the selective mu opioid receptor agonist fentanyl (0.2mg/kg, i.p.) in a novel context and subsequently given a vehicle injection. In separate experiments, locomotor activity, Straub tail, hot plate sensitivity, and conditioned place preference (CPP) were measured. Mice exhibited multiple conditional opioid-like responses including conditional hyperlocomotion, a conditional pattern of opioid-like locomotion, Straub tail, analgesia, and place preference. Modulating drug expectation via administration of fentanyl to "demonstrator" mice in the home cage did not affect the expression of conditioned place preference or the concomitant locomotor activity in "observer" mice. In summary, Pavlovian conditioning of an opioid in a novel context induced multiple conditional opioid-like behaviors and provides a model for studying the neurobiological mechanisms of the placebo response in mice.

  7. Extinction of aversive classically conditioned human sexual response.

    Science.gov (United States)

    Brom, Mirte; Laan, Ellen; Everaerd, Walter; Spinhoven, Philip; Both, Stephanie

    2015-04-01

    Research has shown that acquired subjective likes and dislikes are quite resistant to extinction. Moreover, studies on female sexual response demonstrated that diminished genital arousal and positive affect toward erotic stimuli due to aversive classical conditioning did not extinguish during an extinction phase. Possible resistance to extinction of aversive conditioned sexual responses may have important clinical implications. However, resistance to extinction of aversive conditioned human sexual response has not been studied using extensive extinction trials. This article aims to study resistance to extinction of aversive conditioned sexual responses in sexually functional men and women. A differential conditioning experiment was conducted, with two erotic pictures as conditioned stimulus (CSs) and a painful stimulus as unconditioned stimuli (USs). Only one CS (the CS+) was followed by the US during the acquisition phase. Conditioned responses were assessed during the extinction phase. Penile circumference and vaginal pulse amplitude were assessed, and ratings of affective value and subjective sexual arousal were obtained. Also, a stimulus response compatibility task was included to assess automatic approach and avoidance tendencies. Men and women rated the CS+ more negative as compared with the CS-. During the first trials of the extinction phase, vaginal pulse amplitude was lower in response to the CS+ than in response to the CS-, and on the first extinction trial women rated the CS+ as less sexually arousing. Intriguingly, men did not demonstrate attenuated genital and subjective sexual response. Aversive conditioning, by means of painful stimuli, only affects sexual responses in women, whereas it does not in men. Although conditioned sexual likes and dislikes are relatively persistent, conditioned affect eventually does extinguish. © 2014 International Society for Sexual Medicine.

  8. Tracking Real-Time Changes in Working Memory Updating and Gating with the Event-Based Eye-Blink Rate

    NARCIS (Netherlands)

    Rac-Lubashevsky, R.; Slagter, H.A.; Kessler, Y.

    2017-01-01

    Effective working memory (WM) functioning depends on the gating process that regulates the balance between maintenance and updating of WM. The present study used the event-based eye-blink rate (ebEBR), which presumably reflects phasic striatal dopamine activity, to examine how the cognitive

  9. 30 Fulton's condition, organ indices and haematological response of ...

    African Journals Online (AJOL)

    `123456789jkl''''#

    Abstract. This study was conducted to assess the Fulton's condition, organ indices and haematological response of catfish hybrid ... Haematological study is of immense importance .... give information on the stock composite, age at maturity ...

  10. Extinction of Aversive Classically Conditioned Human Sexual Response

    NARCIS (Netherlands)

    Brom, M.; Laan, E.; Everaerd, W.; Spinhoven, P.; Both, S.

    INTRODUCTION: Research has shown that acquired subjective likes and dislikes are quite resistant to extinction. Moreover, studies on female sexual response demonstrated that diminished genital arousal and positive affect toward erotic stimuli due to aversive classical conditioning did not extinguish

  11. Statistical optimization of cultural conditions by response surface ...

    African Journals Online (AJOL)

    STORAGESEVER

    2009-08-04

    Aug 4, 2009 ... Full Length Research Paper. Statistical optimization of cultural conditions by response surface methodology for phenol degradation by a novel ... Phenol is a hydrocarbon compound that is highly toxic, ... Microorganism.

  12. Investigation of air cleaning system response to accident conditions

    International Nuclear Information System (INIS)

    Andrae, R.W.; Bolstad, J.W.; Foster, R.D.; Gregory, W.S.; Horak, H.L.; Idar, E.S.; Martin, R.A.; Ricketts, C.I.; Smith, P.R.; Tang, P.K.

    1980-01-01

    Air cleaning system response to the stress of accident conditions are being investigated. A program overview and hghlight recent results of our investigation are presented. The program includes both analytical and experimental investigations. Computer codes for predicting effects of tornados, explosions, fires, and material transport are described. The test facilities used to obtain supportive experimental data to define structural integrity and confinement effectiveness of ventilation system components are described. Examples of experimental results for code verification, blower response to tornado transients, and filter response to tornado and explosion transients are reported

  13. CENTRAL AMYGDALOID INVOLVEMENT IN NEUROENDOCRINE CORRELATES OF CONDITIONED STRESS RESPONSES

    NARCIS (Netherlands)

    ROOZENDAAL, B; KOOLHAAS, JM; BOHUS, B

    The purpose of this study was to examine the effects of bilateral electrolytic lesions of the central nucleus of the amygdala (CEA) in comparison with sham lesions on neuroendocrine responses during conditioned emotional stress in male Wistar rats. Lesions in the CEA, made either before or after the

  14. Reinstatement of an Extinguished Fear Conditioned Response in Infant Rats

    Science.gov (United States)

    Revillo, Damian A.; Trebucq, Gastón; Paglini, Maria G.; Arias, Carlos

    2016-01-01

    Although it is currently accepted that the extinction effect reflects new context-dependent learning, this is not so clear during infancy, because some studies did not find recovery of the extinguished conditioned response (CR) in rodents during this ontogenetic stage. However, recent studies have shown the return of an extinguished CR in infant…

  15. Towards Trustworthy Adaptive Case Management with Dynamic Condition Response Graphs

    DEFF Research Database (Denmark)

    Mukkamala, Raghava Rao; Hildebrandt, Thomas; Slaats, Tijs

    2013-01-01

    We describe how the declarative Dynamic Condition Response (DCR) Graphs process model can be used for trustworthy adaptive case management by leveraging the flexible execution, dynamic composition and adaptation supported by DCR Graphs. The dynamically composed and adapted graphs are verified for...

  16. Extinction of aversive classically conditioned human sexual response

    NARCIS (Netherlands)

    Brom, Mirte; Laan, Ellen; Everaerd, Walter; Spinhoven, Philip; Both, Stephanie

    2015-01-01

    Research has shown that acquired subjective likes and dislikes are quite resistant to extinction. Moreover, studies on female sexual response demonstrated that diminished genital arousal and positive affect toward erotic stimuli due to aversive classical conditioning did not extinguish during an

  17. The Perceived Psychological Responsibilities Of A Strength And Conditioning Coach.

    Science.gov (United States)

    Radcliffe, Jon N; Comfort, Paul; Fawcett, Tom

    2016-09-22

    Research is limited in exploring the specific psychology oriented responsibilities of the strength and conditioning professional. The present research explored the psychological responsibilities adopted by accredited strength and conditioning coaches. Participants comprised 10 participants working within the UK, 3 within the USA and 5 within Australia offering a cross section of experience from raging sport disciplines and educational backgrounds. Participants were interviewed either in person or via Skype. Thematic clustering was employed utilizing interpretative phonological analysis to identify common themes. Over half (61%) of the respondents reported that their position as a strength and conditioning coach required additional psychology orientated responsibilities. These comprised a counselling role in the absence of psychologist the use of 'softer skills' in a mentoring role of the athlete during a challenging situation. The coach could play an influential role in shaping the mentality of the team. The coach identifies how the role results in working to relay information for the athlete to other support staff and similarly from the support staff through the athlete. The coach identifies how the role results in working to relay information for the athlete to other support staff and similarly from the support staff to the athlete. In addition to identifying the resonant psychological orientated responsibilities discussion is made with specific focus on the ethical boundary to which strength and conditioning coaches must reside regarding the competencies to provide psychological support.

  18. Response of HEPA filters to simulated-accident conditions

    International Nuclear Information System (INIS)

    Gregory, W.S.; Martin, R.A.; Smith, P.R.; Fenton, D.E.

    1982-01-01

    High-efficiency particulate air (HEPA) filters have been subjected to simulated accident conditions to determine their response to abnormal operating events. Both domestic and European standard and high-capacity filters have been evaluated to determine their response to simulated fire, explosion, and tornado conditions. The HEPA filter structural limitations for tornado and explosive loadings are discussed. In addition, filtration efficiencies during these accident conditions are reported for the first time. Our data indicate efficiencies between 80% and 90% for shock loadings below the structural limit level. We describe two types of testing for ineffective filtration - clean filters exposed to pulse-entrained aerosol and dirty filters exposed to tornado and shock pulses. Efficiency and material loss data are described. Also, the resonse of standard HEPA filters to simulated fire conditions is presented. We describe a unique method of measuring accumulated combustion products on the filter. Additionally, data relating to pressure drop vs accumulated mass during plugging are reported for simulated combustion aerosols. The effects of concentration and moisture levels on filter plugging were evaluated. We are obtaining all of the above data so that mathematical models can be developed for fire, explosion, and tornado accident analysis computer codes. These computer codes can be used to assess the response of nuclear air cleaning systems to accident conditions

  19. From Dynamic Condition Response Structures to Büchi Automata

    DEFF Research Database (Denmark)

    Mukkamala, Raghava Rao; Hildebrandt, Thomas

    2010-01-01

    Recently we have presented distributed dynamic condition response structures (DCR structures) as a declarative process model conservatively generalizing labelled event structures to allow for finite specifications of repeated, possibly infinite behavior. The key ideas are to split the causality...... relation of event structures in two dual relations: the condition relation and the response relation, to split the conflict relation in two relations: the dynamic exclusion and dynamic inclusion, and finally to allow configurations to be multi sets of events. In the present abstract we recall the model...... and show how to characterise the execution of DCR structures and the acceptance condition for infinite runs by giving a map to Bu ̈chi-automata. This is the first step towards automatic verification of processes specified as DCR structures....

  20. Impaired Eye-Blink Conditioning in waggler, a Mutant Mouse With Cerebellar BDNF Deficiency

    OpenAIRE

    Bao, Shaowen; Chen, Lu; Qiao, Xiaoxi; Knusel, Beat; Thompson, Richard F.

    1998-01-01

    In addition to their trophic functions, neurotrophins are also implicated in synaptic modulation and learning and memory. Although gene knockout techniques have been used widely in studying the roles of neurotrophins at molecular and cellular levels, behavioral studies using neurotrophin knockouts are limited by the early-onset lethality and various sensory deficits associated with the gene knockout mice. In the present study, we found that in a spontaneous mutant mouse, waggler, the expressi...

  1. Eyeblink Classical Conditioning and Post-Traumatic Stress Disorder ? A Model Systems Approach

    OpenAIRE

    Schreurs, Bernard G.; Burhans, Lauren B.

    2015-01-01

    Not everyone exposed to trauma suffers flashbacks, bad dreams, numbing, fear, anxiety, sleeplessness, hyper-vigilance, hyperarousal, or an inability to cope, but those who do may suffer from post-traumatic stress disorder (PTSD). PTSD is a major physical and mental health problem for military personnel and civilians exposed to trauma. There is still debate about the incidence and prevalence of PTSD especially among the military, but for those who are diagnosed, behavioral therapy and drug tre...

  2. On the Response of Halophilic Archaea to Space Conditions

    Science.gov (United States)

    Leuko, Stefan; Rettberg, Petra; Pontifex, Ashleigh L.; Burns, Brendan P.

    2014-01-01

    Microorganisms are ubiquitous and can be found in almost every habitat and ecological niche on Earth. They thrive and survive in a broad spectrum of environments and adapt to rapidly changing external conditions. It is of great interest to investigate how microbes adapt to different extreme environments and with modern human space travel, we added a new extreme environment: outer space. Within the last 50 years, technology has provided tools for transporting microbial life beyond Earth’s protective shield in order to study in situ responses to selected conditions of space. This review will focus on halophilic archaea, as, due to their ability to survive in extremes, they are often considered a model group of organisms to study responses to the harsh conditions associated with space. We discuss ground-based simulations, as well as space experiments, utilizing archaea, examining responses and/or resistance to the effects of microgravity and UV in particular. Several halophilic archaea (e.g., Halorubrum chaoviator) have been exposed to simulated and actual space conditions and their survival has been determined as well as the protective effects of halite shown. Finally, the intriguing potential of archaea to survive on other planets or embedded in a meteorite is postulated. PMID:25370029

  3. On the Response of Halophilic Archaea to Space Conditions

    Directory of Open Access Journals (Sweden)

    Stefan Leuko

    2014-02-01

    Full Text Available Microorganisms are ubiquitous and can be found in almost every habitat and ecological niche on Earth. They thrive and survive in a broad spectrum of environments and adapt to rapidly changing external conditions. It is of great interest to investigate how microbes adapt to different extreme environments and with modern human space travel, we added a new extreme environment: outer space. Within the last 50 years, technology has provided tools for transporting microbial life beyond Earth’s protective shield in order to study in situ responses to selected conditions of space. This review will focus on halophilic archaea, as, due to their ability to survive in extremes, they are often considered a model group of organisms to study responses to the harsh conditions associated with space. We discuss ground-based simulations, as well as space experiments, utilizing archaea, examining responses and/or resistance to the effects of microgravity and UV in particular. Several halophilic archaea (e.g., Halorubrum chaoviator have been exposed to simulated and actual space conditions and their survival has been determined as well as the protective effects of halite shown. Finally, the intriguing potential of archaea to survive on other planets or embedded in a meteorite is postulated.

  4. Classic conditioning of the ventilatory responses in rats.

    Science.gov (United States)

    Nsegbe, E; Vardon, G; Perruchet, P; Gallego, J

    1997-10-01

    Recent authors have stressed the role of conditioning in the control of breathing, but experimental evidence of this role is still sparse and contradictory. To establish that classic conditioning of the ventilatory responses can occur in rats, we performed a controlled experiment in which a 1-min tone [conditioned stimulus (CS)] was paired with a hypercapnic stimulus [8.5% CO2, unconditioned stimulus (US)]. The experimental group (n = 9) received five paired CS-US presentations, followed by one CS alone to test conditioning. This sequence was repeated six times. The control group (n = 7) received the same number of CS and US, but each US was delivered 3 min after the CS. We observed that after the CS alone, breath duration was significantly longer in the experimental than in the control group and mean ventilation was significantly lower, thus showing inhibitory conditioning. This conditioning may have resulted from the association between the CS and the inhibitory and aversive effects of CO2. The present results confirmed the high sensitivity of the respiratory controller to conditioning processes.

  5. Chronic condition self-management: expectations of responsibility.

    Science.gov (United States)

    Lawn, Sharon; McMillan, John; Pulvirenti, Mariastella

    2011-08-01

    While self-management may be beneficial for many patients it assumes and encourages a particular conception of responsibility and self-management that may not fit with all patients' experience of their chronic conditions and their management. It therefore warrants further examination. We examine the concept of self-management and responsibility from a range of standpoints, focusing on the Australian context. Attempts to meet people's needs run the risk of imposing specific conceptions of how people should live their lives. While self-management appears to be consistent with placing patients' needs, values and priorities at the heart of healthcare, ill-defined assumptions about responsibility may confound these goals. Reflection on social determinants of health, the context in which patients seek self-management support from health services, and how their needs and preferences are listened to by health professionals, is critical for the collaborative self-management partnership between them to be effectively realized. Providing services without reflecting on the meaning of self-management for the person with chronic conditions creates unintended assumptions about responsibility, engagement and care provision which may serve to alienate and further stigmatise some patients. Often, these are the very patients with complex needs who need such service support the most. Crown Copyright © 2010. Published by Elsevier Ireland Ltd. All rights reserved.

  6. Conditioned responses elicited by experimentally produced cues for smoking.

    Science.gov (United States)

    Mucha, R F; Pauli, P; Angrilli, A

    1998-03-01

    Several theories of drug-craving postulate that a signal for drug elicits conditioned responses. However, depending on the theory, a drug cue is said to elicit drug similar, drug compensatory, positive motivational, and negative motivational effects. Since animal data alone cannot tease apart the relative importance of different cue-related processes in the addict, we developed and examined a model of drug cues in the human based on a two-sound, differential conditioning procedure using smoking as the reinforcer. After multiple pairings of a sound with smoking, there was a preference for the smoking cue on a conditioned preference test. The acute effects of smoking (increased heart rate, respiration rate, skin conductance level, skin conductance fluctuations, EEG beta power and trapezius EMG, decreased alpha power) were not affected by the smoking cue, although subjects drew more on their cigarette in the presence of the smoking cue than in the presence of a control cue. Moreover, the cue did not change baseline behaviour except for a possible increase in EEG beta power and an increase in trapezius EMG at about the time when smoking should have occurred. The findings confirm the value of experimental models of drug cues in the human for comparing different cue phenomena in the dependent individual. They indicate that an acquired signal for drug in the human may elicit incentive motivational effects and associated preparatory motor responses in addition to possible conditioned tolerance.

  7. Bridge Condition Assessment based on Vibration Responses of Passenger Vehicle

    International Nuclear Information System (INIS)

    Miyamoto, Ayaho; Yabe, Akito

    2011-01-01

    In this paper, we propose a new method of assessing the condition of existing short- and medium-span reinforced/prestressed concrete bridges based on vibration monitoring data obtained from a public bus. This paper not only describes details of a prototype monitoring system that uses information technology and sensors capable of providing more accurate knowledge of bridge performance than conventional ways but also shows a few specific examples of bridge condition assessment based on vehicle vibrations measured by using an in-service public bus equipped with vibration measurement instrumentation. This paper also describes a sensitivity analysis of deteriorating bridges based on simulation of the acceleration response of buses conducted by the 'substructure method' employing a finite element model to verify the above bridge performance results. The main conclusions obtained in this study can be summarized as follows: (1) Because the vibration responses of passenger vehicles, such as buses, have a good linear relationship with the vibration responses of the target bridges, the proposed system can be used as a practical monitoring system for bridge condition assessment. (2) The results of sensitivity analysis performed by the substructure method show that bus vibration responses are useful for evaluating target bridge performance. (3) The proposed method was applied to a network of real bridges in a local area to evaluate its effectiveness. The results indicate that the proposed method can be used to prioritize the repair/strengthening works of existing bridges based on various vibration information in order to help bridge administrators establish rational maintenance strategies.

  8. Response of Simple, Model Systems to Extreme Conditions

    Energy Technology Data Exchange (ETDEWEB)

    Ewing, Rodney C. [Univ. of Michigan, Ann Arbor, MI (United States); Lang, Maik [Univ. of Michigan, Ann Arbor, MI (United States)

    2015-07-30

    The focus of the research was on the application of high-pressure/high-temperature techniques, together with intense energetic ion beams, to the study of the behavior of simple oxide systems (e.g., SiO2, GeO2, CeO2, TiO2, HfO2, SnO2, ZnO and ZrO2) under extreme conditions. These simple stoichiometries provide unique model systems for the analysis of structural responses to pressure up to and above 1 Mbar, temperatures of up to several thousands of kelvin, and the extreme energy density generated by energetic heavy ions (tens of keV/atom). The investigations included systematic studies of radiation- and pressure-induced amorphization of high P-T polymorphs. By studying the response of simple stoichiometries that have multiple structural “outcomes”, we have established the basic knowledge required for the prediction of the response of more complex structures to extreme conditions. We especially focused on the amorphous state and characterized the different non-crystalline structure-types that result from the interplay of radiation and pressure. For such experiments, we made use of recent technological developments, such as the perforated diamond-anvil cell and in situ investigation using synchrotron x-ray sources. We have been particularly interested in using extreme pressures to alter the electronic structure of a solid prior to irradiation. We expected that the effects of modified band structure would be evident in the track structure and morphology, information which is much needed to describe theoretically the fundamental physics of track-formation. Finally, we investigated the behavior of different simple-oxide, composite nanomaterials (e.g., uncoated nanoparticles vs. core/shell systems) under coupled, extreme conditions. This provided insight into surface and boundary effects on phase stability under extreme conditions.

  9. SAP FLOW RESPONSE OF CHERRY TREES TO WEATHER CONDITION

    Directory of Open Access Journals (Sweden)

    Á. JUHÁSZ

    2011-03-01

    Full Text Available Sap flow response of cherry trees to weather condition. Themain goal of our study is to measure water-demand of cherry trees budded ontodifferent rootstocks by sapflow equipment and to study the sap flow response to themeteorological factors. The investigations are carried out in Soroksár in Hungary at‘Rita’ sweet cherry orchard. The pattern of sapflow was analyzed in relation ofsolar radiation, vapour pressure deficit and air temperature. Between solar radiationand sap flow was found a parabolic relation, daily pattern of sapflow is in closerelation (cubic also to vapour pressure deficit. No significant relationship existedbetween sapflow and air temperature. The sapflow performance of sweet cherrytrees on different rootstocks showed typical daily characters.

  10. Placental baseline conditions modulate the hyperoxic BOLD-MRI response.

    Science.gov (United States)

    Sinding, Marianne; Peters, David A; Poulsen, Sofie S; Frøkjær, Jens B; Christiansen, Ole B; Petersen, Astrid; Uldbjerg, Niels; Sørensen, Anne

    2018-01-01

    Human pregnancies complicated by placental dysfunction may be characterized by a high hyperoxic Blood oxygen level-dependent (BOLD) MRI response. The pathophysiology behind this phenomenon remains to be established. The aim of this study was to evaluate whether it is associated with altered placental baseline conditions, including a lower oxygenation and altered tissue morphology, as estimated by the placental transverse relaxation time (T2*). We included 49 normal pregnancies (controls) and 13 pregnancies complicated by placental dysfunction (cases), defined by a birth weight baseline BOLD)/baseline BOLD) from a dynamic single-echo gradient-recalled echo (GRE) MRI sequence and the absolute ΔT2* (hyperoxic T2*- baseline T2*) from breath-hold multi-echo GRE sequences. In the control group, the relative ΔBOLD response increased during gestation from 5% in gestational week 20 to 20% in week 40. In the case group, the relative ΔBOLD response was significantly higher (mean Z-score 4.94; 95% CI 2.41, 7.47). The absolute ΔT2*, however, did not differ between controls and cases (p = 0.37), whereas the baseline T2* was lower among cases (mean Z-score -3.13; 95% CI -3.94, -2.32). Furthermore, we demonstrated a strong negative linear correlation between the Log 10 ΔBOLD response and the baseline T2* (r = -0.88, p baseline conditions, as the absolute increase in placental oxygenation (ΔT2*) does not differ between groups. Copyright © 2017 Elsevier Ltd. All rights reserved.

  11. Intermediate Conditions of Democratic Accountability: A Response to Electoral Skepticism

    Directory of Open Access Journals (Sweden)

    J. S. Maloy

    2015-08-01

    Full Text Available Attempts to respond to “democratic deficits” in modern constitutional republics must contend with the broad scholarly trend of electoral skepticism. While generally casting doubt on periodic competitive elections’ suitability as vehicles of accountability, electoral skepticism does not necessarily entail an absolute devaluation of elections. Some normative and empirical research responds to this trend by refocusing attention on values other than popular power, such as civil peace, which might be served by periodic competitive elections. Another response short of abandoning the value of popular power, however, is to draw out possibilities for institutional design from the restricted conditions under which previous study has found electoral accountability to be plausible or likely. This second task requires an empirically informed exercise in political theory. Pursuing it in a programmatic and policy-relevant way requires descending from the grand, systemic level of constitutional structures and electoral formulae to intermediate (or middle-range institutional conditions of accountability, such as rules about parties, campaigns, and election administration. My analysis reinterprets principal-agent models to develop four general types of crucial condition for electoral accountability, and then ramifies this scheme by reference to recent empirical research. The result is a “top ten” list of specific institutional factors that could be theoretically decisive in helping or hindering electoral accountability. These ten conditions could guide future research designs and reform proposals alike.

  12. What Does Eye-Blink Rate Variability Dynamics Tell Us About Cognitive Performance?

    Directory of Open Access Journals (Sweden)

    Rafal Paprocki

    2017-12-01

    Full Text Available Cognitive performance is defined as the ability to utilize knowledge, attention, memory, and working memory. In this study, we briefly discuss various markers that have been proposed to predict cognitive performance. Next, we develop a novel approach to characterize cognitive performance by analyzing eye-blink rate variability dynamics. Our findings are based on a sample of 24 subjects. The subjects were given a 5-min resting period prior to a 10-min IQ test. During both stages, eye blinks were recorded from Fp1 and Fp2 electrodes. We found that scale exponents estimated for blink rate variability during rest were correlated with subjects' performance on the subsequent IQ test. This surprising phenomenon could be explained by the person to person variation in concentrations of dopamine in PFC and accumulation of GABA in the visual cortex, as both neurotransmitters play a key role in cognitive processes and affect blinking. This study demonstrates the possibility that blink rate variability dynamics at rest carry information about cognitive performance and can be employed in the assessment of cognitive abilities without taking a test.

  13. Response rate and reinforcement rate in Pavlovian conditioning.

    Science.gov (United States)

    Harris, Justin A; Carpenter, Joanne S

    2011-10-01

    Four experiments used delay conditioning of magazine approach in rats to investigate the relationship between the rate of responding, R, to a conditioned stimulus (CS) and the rate, r, at which the CS is reinforced with the unconditioned stimulus (US). Rats were concurrently trained with four variable-duration CSs with different rs, either as a result of differences in the mean CS-US interval or in the proportion of CS presentations that ended with the US. In each case, R was systematically related to r, and the relationship was very accurately characterized by a hyperbolic function, R = Ar/(r +c). Accordingly, the reciprocal of these two variables-response interval, I (= 1/R), and CS-US interval, i (= 1/r) - were related by a simple affine (straight line) transformation, I = mi+b. This latter relationship shows that each increment in the time that the rats had to wait for food produced a linear increment in the time they waited between magazine entries. We discuss the close agreement between our findings and the Matching Law (Herrnstein, 1970) and consider their implications for both associative theories (e.g., Rescorla & Wagner, 1972) and nonassociative theories (Gallistel & Gibbon, 2000) of conditioning. (PsycINFO Database Record (c) 2011 APA, all rights reserved).

  14. [Exposure to addictogenic substances, conditioned response and treatment of the exposure with response prevention].

    Science.gov (United States)

    Khazaal, Y; Frésard, E; Zullino, D

    2007-01-01

    Exposure to drugs or related cues is associated with psycho-physiological reactivity. These responses are conditioned during periods of active consumption. Exposure with response prevention (EPR) is a treatment established for anxiety disorder and aims to reduce anxiety by an extinction of previously conditioned responses. The conditioning recognized in additive processes has led to research into EPR's therapeutic potential for treating addiction. This paper is a review of the main studies on reactivity to cues, and EPR, particularly with respect to addiction to alcohol, opiates, cocaine and tobacco. This review is based on information from the Medline database, dealing with cue reactivity, attentional bias during exposure to cues and exposure treatment for addiction in general and, in particular, for each of the aforementioned substances. Exposure to drug-related cues is clearly associated with psycho-physiological reactivity and with attentional bias. Those phenomena are associated with craving and more difficulty in maintaining abstinence. The subject's attention is thus held by a large number of drug-related environmental stimuli. These observations are linked with conditioning phenomena and suggest the possibility of treatment by EPR conditioning extinction procedures. EPR has been most widely studied for abuse and alcohol addiction. Case reports give favourable outcomes. Results from controlled studies are less clear. Studies on patients addicted to cocaine or heroine are still limited and not conclusive. Different controlled studies on EPR for nicotine addiction have not produced conclusions in favour of this treatment. Generally, the EPR procedures used vary among studies. Studies focussing particularly on the evolution of physiological responses in a laboratory setting after EPR have demonstrated reduced autonomic nervous system activity. These results do not consistently lead to a reduction in consumption behaviour and in craving when the patient is in

  15. Diverging responses of tropical Andean biomes under future climate conditions.

    Directory of Open Access Journals (Sweden)

    Carolina Tovar

    Full Text Available Observations and projections for mountain regions show a strong tendency towards upslope displacement of their biomes under future climate conditions. Because of their climatic and topographic heterogeneity, a more complex response is expected for biodiversity hotspots such as tropical mountain regions. This study analyzes potential changes in the distribution of biomes in the Tropical Andes and identifies target areas for conservation. Biome distribution models were developed using logistic regressions. These models were then coupled to an ensemble of 8 global climate models to project future distribution of the Andean biomes and their uncertainties. We analysed projected changes in extent and elevational range and identified regions most prone to change. Our results show a heterogeneous response to climate change. Although the wetter biomes exhibit an upslope displacement of both the upper and the lower boundaries as expected, most dry biomes tend to show downslope expansion. Despite important losses being projected for several biomes, projections suggest that between 74.8% and 83.1% of the current total Tropical Andes will remain stable, depending on the emission scenario and time horizon. Between 3.3% and 7.6% of the study area is projected to change, mostly towards an increase in vertical structure. For the remaining area (13.1%-17.4%, there is no agreement between model projections. These results challenge the common believe that climate change will lead to an upslope displacement of biome boundaries in mountain regions. Instead, our models project diverging responses, including downslope expansion and large areas projected to remain stable. Lastly, a significant part of the area expected to change is already affected by land use changes, which has important implications for management. This, and the inclusion of a comprehensive uncertainty analysis, will help to inform conservation strategies in the Tropical Andes, and to guide similar

  16. Biocrust spectral response as affected by changing climatic conditions

    Science.gov (United States)

    Rodriguez-Caballero, Emilio; Guirado, Emilio; Escribano, Paula; Reyes, Andres; Weber, Bettina

    2017-04-01

    Drylands are characterized by scarce vegetation coverage and low rates of biological activity, both constrained by water scarcity. Under these conditions, biocrusts form key players of ecosystem functioning. They comprise complex poikilohydric communities of cyanobacteria, algae, lichens and bryophytes together with heterotrophic bacteria, archaea and fungi, which cover the uppermost soil layer. Biocrusts can cope with prolonged phases of drought, being rapidly re-activated when water becomes available again. Upon reactivation, biocrusts almost immediately turn green, fixing atmospheric carbon and nitrogen and increasing ecosystem productivity. However, due to their inconspicuous growth they have only rarely been analysed and spatially and temporally continuous information on their response to water pulses is missing. These data are particularly important under changing climatic conditions predicting an increase in aridity and variations in precipitation patterns within most of the dryland regions. In the present study, we used multi-temporal series of NDVI obtained from LANDSAT images to analyze biocrust and vegetation response to water pulses within the South African Succulent Karoo and we predicted their future response under different climate change scenarios. The results showed that biocrust and vegetation greenness are controlled by aridity, solar radiation and soil water content, showing similar annual patterns, with minimum values during dry periods that increased within the rainy season and decreased again after the onset of drought. However, biocrusts responded faster to water availability and turned green almost immediately after small rains, producing a small NDVI peak only few days after rainfall, whereas more time was needed for vegetation to grow new green tissue. However, once the photosynthetic tissue of vegetation was restored, it caused the highest increase of NDVI values after the rain. Predicted changes in precipitation patterns and aridity

  17. Physiological Responses to Two Hypoxic Conditioning Strategies in Healthy Subjects.

    Science.gov (United States)

    Chacaroun, Samarmar; Borowik, Anna; Morrison, Shawnda A; Baillieul, Sébastien; Flore, Patrice; Doutreleau, Stéphane; Verges, Samuel

    2016-01-01

    Objective: Hypoxic exposure can be used as a therapeutic tool by inducing various cardiovascular, neuromuscular, and metabolic adaptations. Hypoxic conditioning strategies have been evaluated in patients with chronic diseases using either sustained (SH) or intermittent (IH) hypoxic sessions. Whether hypoxic conditioning via SH or IH may induce different physiological responses remains to be elucidated. Methods: Fourteen healthy active subjects (7 females, age 25 ± 8 years, body mass index 21.5 ± 2.5 kg·m -2 ) performed two interventions in a single blind, randomized cross-over design, starting with either 3 x SH (48 h apart), or 3 x IH (48 h apart), separated by a 2 week washout period. SH sessions consisted of breathing a gas mixture with reduced inspiratory oxygen fraction (FiO 2 ), continuously adjusted to reach arterial oxygen saturations (SpO 2 ) of 70-80% for 1 h. IH sessions consisted of 5 min with reduced FiO 2 (SpO 2 = 70-80%), followed by 3-min normoxia, repeated seven times. During the first (S1) and third (S3) sessions of each hypoxic intervention, cardiorespiratory parameters, and muscle and pre-frontal cortex oxygenation (near infrared spectroscopy) were assessed continuously. Results : Minute ventilation increased significantly during IH sessions (+2 ± 2 L·min -1 ) while heart rate increased during both SH (+11 ± 4 bpm) and IH (+13 ± 5 bpm) sessions. Arterial blood pressure increased during all hypoxic sessions, although baseline normoxic systolic blood pressure was reduced from S1 to S3 in IH only (-8 ± 11 mmHg). Muscle oxygenation decreased significantly during S3 but not S1, for both hypoxic interventions (S3: SH -6 ± 5%, IH -3 ± 4%); pre-frontal oxygenation decreased in S1 and S3, and to a greater extent in SH vs. IH (-13 ± 3% vs. -6 ± 6%). Heart rate variability indices indicated a significantly larger increase in sympathetic activity in SH vs. IH (lower SDNN, PNN50, and RMSSD values in SH). From S1 to S3, further reduction in heart

  18. Detection, diagnosis, and treatment of accident conditions using response trees

    International Nuclear Information System (INIS)

    Nelson, W.R.

    1980-01-01

    Response Trees were developed at the LOFT facility in 1978 and included in the Plant Operating Manual (POM) to assist reactor operators in selecting emergency procedures. In an emergency situation the operator would manually gather data and evaluate the trees to select the appropriate procedures. As a portion of the LOFT Augmented Operator Capability (AOC) Program, the response tree methodology has been extended so that a computer can be used to evaluate the trees and recommend an appropriate response for an accident. Techniques for diagnosing failures within a cooling mode have also been investigated. This paper summarizes these additions to the response tree methodology

  19. Plant response to sunflower seeds to osmotic conditioning

    Directory of Open Access Journals (Sweden)

    Camila Santos Barros de Morais

    2014-10-01

    Full Text Available The aim of this study was to evaluate the effect of seeds osmotic conditioning in seedlings emergence and plants performance of sunflower. Three lots of seeds sunflower (Catissol, was submited to osmotic conditioning with polyethylene glycol solution, –2,0 MPa in aerated system, under 15 ºC for 8 hour and then was evaluated for germination tests and vigour. Under filed conditions was conducted emergency evaluations of seedling, plants development as well as the productivity and seeds quality, and the accumulation of nutrients in the seeds. The osmotic conditioning improve the survival of seedling, the dry matter mass to aerial part of plants from 60 days after sowing and oil content, in lots with low seeds physiological quality. The osmotic conditioning not increase the seeds yield but promotes the vigour of seeds produced, regardless of the lot used for sowing seeds.

  20. Transcriptional profiles of Treponema denticola in response to environmental conditions.

    Directory of Open Access Journals (Sweden)

    Ian McHardy

    Full Text Available The periodontal pathogen T. denticola resides in a stressful environment rife with challenges, the human oral cavity. Knowledge of the stress response capabilities of this invasive spirochete is currently very limited. Whole genome expression profiles in response to different suspected stresses including heat shock, osmotic downshift, oxygen and blood exposure were examined. Most of the genes predicted to encode conserved heat shock proteins (HSPs were found to be induced under heat and oxygen stress. Several of these HSPs also seem to be important for survival in hypotonic solutions and blood. In addition to HSPs, differential regulation of many genes encoding metabolic proteins, hypothetical proteins, transcriptional regulators and transporters was observed in patterns that could betoken functional associations. In summary, stress responses in T. denticola exhibit many similarities to the corresponding stress responses in other organisms but also employ unique components including the induction of hypothetical proteins.

  1. Pleurodeles Waltl Humoral Immune Response under Spaceflight Conditions

    Science.gov (United States)

    Bascove, Matthieu; Touche, Nadege; Frippiat, Jean-Pol

    2008-06-01

    The immune system is an important regulatory mechanism affected by spaceflights. In a previous work, we performed a first study of the humoral immune response induced by the immunization of Pleurodeles waltl during a 5 months stay onboard the Mir space station. This analysis indicated that heavy-chain variable domains of specific IgM are encoded by genes of the VHII and VHVI families. However, the contributions of these two families to IgM heavy-chains are different in flown animals [1]. To better understand this immune response modification, we have now determined how individual VH genes have been used to build specific IgM binding sites in animals immunized on earth or in space. This new study revealed quantitative and qualitative modifications in VH genes expression. These data confirm that a spaceflight might affect the humoral response.

  2. Association between neuroticism and amygdala responsivity emerges under stressful conditions

    NARCIS (Netherlands)

    Everaerd, Daphne; Klumpers, Floris; van Wingen, Guido; Tendolkar, Indira; Fernández, Guillén

    2015-01-01

    Increased amygdala reactivity in response to salient stimuli is seen in patients with affective disorders, in healthy subjects at risk for these disorders, and in stressed individuals, making it a prime target for mechanistic studies into the pathophysiology of affective disorders. However, whereas

  3. Response of a DSNP pressurizer model under accident conditions

    International Nuclear Information System (INIS)

    Saphier, D.; Kallfelz, J.; Belblidia, L.

    1986-01-01

    Recently a new pressurizer model was developed for the DSNP simulation language. The model was connected to a simulation of the Trojan pressurized water reactor (PWR) and tested by simulating a loss-of-off-site power (LOSP) anticipated transient without scram. The results compare well to a similar study performed using the RELAP code. The pressurizer model and its response to the LOSP accident are presented

  4. Biological and Theoretical Studies of Adaptive Networks: The Conditioned Response.

    Science.gov (United States)

    1992-06-30

    suggest experimental tests and provide direction for physiological studies. 14 SU~la TIPO ~IS- NIJUMS Of PAGIS 17. @1d-ftA ITY CLASSIPtCATICON...mancte suditioned inhibition of the rabbit’s nictitating membrane response, CI tasks require the active suppression of CRs in the Bull . Psychon. Soc., 20... Bull ., 84 (1977) encephalon and mesencephalon26. 690-711. Several lines of evidence suggest that the septal and 8 Evans,J.A.C. and Thornton, E.W

  5. Visualizing mushroom body response to a conditioned odor in honeybees

    Science.gov (United States)

    Faber, Till; Menzel, Randolf

    2001-11-01

    Combining differential conditioning with optophysiological recordings of bee brain activity allows the investigation of learning-related changes in complex neural systems. In this study we focused on the mushroom bodies of the bee brain. Presenting different odors to the animal leads to significant activation of the mushroom body lips. After differential conditioning, the rewarded odor leads to stronger activation than it did before training. Activation by the unrewarded odor remains unchanged. These results resemble findings in the bee's antennal lobes, which are the first olfactory relay station in the insect brain. As an integrative neural network, enhanced activation of the mushroom body lip may carry additional information, i.e., for processing odor concentrations.

  6. Effect of support conditions on structural response under dynamic loading

    International Nuclear Information System (INIS)

    Akram, T.; Memon, S.A.

    2008-01-01

    In design practice, dynamic structural analysis is carried out with base of structure considered as fixed; this means that foundation is placed on rock like soil material. While conducting this type of analyses the role of foundation and soil behaviour is totally neglected. The actions in members and loads transferred at foundation level obtained in this manner do not depict the true structural behaviour. FEM (Finite Element Methods) analysis where both superstructure and foundation soil are coupled together is quite complicated and expensive for design environments. A simplified model is required to depict dynamic response of structures with foundations based on flexible soils. The primary purpose of this research is to compare the superstructure dynamic responses of structural systems with fixed base to that of simple soil model base. The selected simple soil model is to be suitable for use in a design environment to give more realistic results. For this purpose building models are idealized with various heights and structural systems in both 2D (Two Dimensional) and 3D (Three Dimensional) space. These models are then provided with visco-elastic supports representing three soil bearing capacities and the analysis results are compared to that of fixed supports models. The results indicate that fixed support system underestimates natural time period of the structures. Dynamic behavior and force response of visco-elastic support is different from fixed support model. Fixed support models result in over designed base columns and under designed beams. (author)

  7. Response of steel box columns in fire conditions

    Directory of Open Access Journals (Sweden)

    Mahmood Yahyai

    2017-05-01

    Full Text Available Effect of elevated temperatures on the mechanical properties of steel, brings the importance of investigating the effect of fire on the steel structures anxiously. Columns, as the main load-carrying part of a structure, can be highly vulnerable to the fire. In this study, the behavior of steel gravity columns with box cross section exposed to fire has been investigated. These kinds of columns are widely used in common steel structures design in Iran. In current study, the behavior of such columns in fire conditions is investigated through the finite element method. To perform this, the finite element model of a steel column which has been previously tested under fire condition, was prepared. Experimental loading and boundary conditions were considered in the model and was analyzed. Results were validated by experimental data and various specimens of gravity box columns were designed according to the Iran’s steel buildings code, and modeled and analyzed using Abaqus software. The effect of width to thickness ratio of column plates, the load ratio and slenderness on the ultimate strength of the column was investigated, and the endurance time was estimated under ISO 834 standard fire curve. The results revealed that an increase in width to thickness ratio and load ratio leads to reduction of endurance time and the effect of width to thickness ratio on the ultimate strength of the column decreases with temperature increase.

  8. Mechanical response of shock conditioned HPNS-5 (R-1) grout

    International Nuclear Information System (INIS)

    Plannerer, H.N.

    1997-01-01

    HPNS-5 (R-1) grout is a portland cement formulated mix designed for use as a rigid containment plug in vertical boreholes at the Nevada Test Site. Coincident with field testing of this grout in 1991 and 1992 , two arums of the grout mix were collected and positioned in the by pass drift of the DISTANT ZENITH event to expose the grout to passage of a nuclear driven stress wave. The drums were later retrieved to determine the mechanical behavior of the shock conditioned grout. Sealed hollow tubes positioned within the grout-filled drums to detect ductile flow on passage of the stress wave were found partially to completely filled with HPNS-5 grout following the experiment. Static mechanical tests support the evidence for ductile flow and place the transition from brittle fracture failure to ductile behavior in the shock conditioned grout at a confining stress between ambient and 5 MPa (725 psi). Uniaxial and triaxial tests delineated a stress-strain field for interstice collapse that interposes between the mechanics of linear elastic deformation and dilatancy. Hydrostatic stress loading between 25 MPa (3.6 ksi) and 60 MPa (8.7 ksi) results in a significant change of permanent set from 1% to greater than 15% volume strain

  9. Honey bees (Apis mellifera) as explosives detectors: exploring proboscis extension reflex conditioned response to trinitrotolulene (TNT)

    Energy Technology Data Exchange (ETDEWEB)

    Taylor-mccabe, Kirsten J [Los Alamos National Laboratory; Wingo, Robert M [Los Alamos National Laboratory; Haarmann, Timothy K [Los Alamos National Laboratory

    2008-01-01

    We examined honey bee's associative learning response to conditioning with trinitrotolulene (TNT) vapor concentrations generated at three temperatures and their ability to be reconditioned after a 24 h period. We used classical conditioning of the proboscis extension (PER) in honey bees using TNT vapors as the conditioned stimulus and sucrose as the unconditioned stimulus. We conducted fifteen experimental trials with an explosives vapor generator set at 43 C, 25 C and 5 C, producing three concentrations of explosives (1070 ppt, 57 ppt, and 11 ppt). Our objective was to test the honey bee's ability to exhibit a conditioned response to TNT vapors at all three concentrations by comparing the mean percentage of honey bees successfully exhibiting a conditioned response within each temperature group. Furthermore, we conducted eight experimental trials to test the honey bee's ability to retain their ability to exhibit a conditioned response to TNT after 24h period by comparing the mean percentage of honey bees with a conditioned response TNT on the first day compared to the percentage of honey bees with a conditioned response to TNT on the second day. Results indicate that there was no significant difference between the mean percentage of honey bees with a conditioned response to TNT vapors between three temperature groups. There was a significant difference between the percentage of honey bees exhibiting conditioned response on the first day of training compared to the percentage of honey bees exhibiting conditioned response 24 h after training. Our experimental results indicate that honey bees can be trained to exhibit a conditioned response to a range of TNT concentrations via PER However, it appears that the honey bee's ability to retain the conditioned response to TNT vapors after 24h significantly decreases.

  10. Does dual-tasking neutralize emotional memory and reduce conditioned responses?

    NARCIS (Netherlands)

    Engelhard, I.M.; Krypotos, A.M.; Leer, A.; van Dis, E.A.M.

    2016-01-01

    This experiment tested whether dual-tasking (i.e., recalling the emotional memory while performing a visuospatial dual-task) neutralizes emotional memory, thereby decreasing conditioned responses. Undergraduates completed a differential conditioning paradigm with pictures of food items as

  11. Dynamic response of Belene WWER-1000 to seismic loading conditions

    International Nuclear Information System (INIS)

    Krutzik, N.J.; Petrovski, D.; Sachanski, S.

    1993-01-01

    Within the framework of investigating of the capacity of the WWER-100 at the Belene site, an analysis was performed using revised seismic input data as well as two alternative foundation concepts (natural soil and soil exchange). The starting point for the analysis was the development of a suitable model of the coupled structures (base building, external building, containment, internal structure) and soil taking into account the real properties of the originally layered as well as the exchanged soil. The soil-structure effects were considered according to the analytical method employed, either through soil impedance (substructure method) or explicitly by a complex (direct method). On the basis of the results obtained by the two methods (substructure and direct method) the seismic safety of the complex structures for different foundation concepts was evaluated. By comparing the calculated structural response with the design spectra originally used for the design of components and systems the available safety margin was estimated

  12. Elastic Nonlinear Response in Granular Media Under Resonance Conditions

    Science.gov (United States)

    Jia, X.; Johnson, P. A.

    2004-12-01

    We are studying the elastic linear and nonlinear behavior of granular media using dynamic wave methods. In the work presented here, our goal is to quantify the elastic nonlinear response by applying wave resonance. Resonance studies are desirable because they provide the means to easily study amplitude dependencies of elastic nonlinear behavior and thus to characterize the physical nature of the elastic nonlinearity. This work has implications for a variety of topics, in particular, the in situ nonlinear response of surface sediments. For this work we constructed an experimental cell in which high sensitivity dynamic resonance studies were conducted using granular media under controlled effective pressure. We limit our studies here to bulk modes but have the capability to employ shear waves as well. The granular media are composed of glass beads held under pressure by a piston, while applying resonance waves from transducers as both the excitation and the material probe. The container is closed with two fitted pistons and a normal load is applied to the granular sample across the top piston. Force and displacement are measured directly. Resonant frequency sweeps with frequencies corresponding to the fundamental bulk mode are applied to the longitudinal source transducer. The pore pressure in the system is 1 atm. The glass beads used in our experiments are of diameter 0.5 mm, randomly deposited in a duralumin cylinder of diameter 30 mm and height of 15 mm. This corresponds to a granular skeleton acoustic wave velocity of v ª 750m/s under 50 N of force [0.07 Mpa]. The loaded system gives fundamental mode resonances in the audio frequency band at half a wavelength where resonance frequency is effective-pressure dependent. The volume fraction of glass beads thus obtained is found to be 0.63 ± 0.01. Plane-wave generating and detecting transducers of diameter 30 mm are placed on axis at the top and bottom of the cylindrical container in direct contact with the glass

  13. Social anxiety and cardiovascular responses to active coping conditions

    Directory of Open Access Journals (Sweden)

    MARGIT GRAMER

    2006-03-01

    Full Text Available This study assessed the influence of trait social anxiety on cardiovascular, emotional and behavioral responses to active performance situations representing social and cognitive demands. Thirty-six male and thirty-six female students categorized as either high or low in trait social anxiety performed a mental arithmetic task and two interpersonal tasks requiring persuasive behavior: Preparation and Performance of a Speech, Role-played Interpersonal Interactions. The cardiovascular effects of social anxiety varied over experimental stressors and appear to reflect differences in effort or task engagement rather than differential affective experiences. During Role-played Interactions high socially anxious subjects displayed lower increases in systolic blood pressure compared to low anxious participants. This effect was partially mediated by behavioral indicators of social competence and suggests a more inhibited coping approach of socially anxious participants. Findings for Mental Arithmetic were in the opposite direction, high socially anxious subjects displayed greater heart rate effects. In the absence of group differences in state anxiety this effect might result from stronger audience effects on effort or task motivation in socially anxious participants. These findings strengthen the view that active performance situations elicit cardiovascular effects that are largely attributable to differences in task engagement. The data also indicate the importance of considering situational factors in social anxiety research.

  14. Cerebellar Norepinephrine Modulates Learning of Delay Classical Eyeblink Conditioning: Evidence for Post-Synaptic Signaling via PKA

    Science.gov (United States)

    Fister, Mathew; Bickford, Paula C.; Cartford, M. Claire; Samec, Amy

    2004-01-01

    The neurotransmitter norepinephrine (NE) has been shown to modulate cerebellar-dependent learning and memory. Lesions of the nucleus locus coeruleus or systemic blockade of noradrenergic receptors has been shown to delay the acquisition of several cerebellar-dependent learning tasks. To date, no studies have shown a direct involvement of…

  15. Fear conditioned responses and PTSD symptoms in children: Sex differences in fear-related symptoms.

    Science.gov (United States)

    Gamwell, Kaitlyn; Nylocks, Maria; Cross, Dorthie; Bradley, Bekh; Norrholm, Seth D; Jovanovic, Tanja

    2015-11-01

    Fear conditioning studies in adults have found that posttraumatic stress disorder (PTSD) is associated with heightened fear responses and impaired discrimination. The objective of the current study was to examine the association between PTSD symptoms and fear conditioned responses in children from a highly traumatized urban population. Children between 8 and 13 years old participated in a fear conditioning study in addition to providing information about their trauma history and PTSD symptoms. Results showed that females showed less discrimination between danger and safety signals during conditioning compared to age-matched males. In boys, intrusive symptoms were predictive of fear responses, even after controlling for trauma exposure. However, in girls, conditioned fear to the danger cue was predictive of self-blame and fear of repeated trauma. This study suggests there are early sex differences in the patterns of fear conditioning and that these sex differences may translate to differential risk for trauma-related psychopathology. © 2015 Wiley Periodicals, Inc.

  16. Information about the model's unconditioned stimulus and response in vicarious classical conditioning.

    Science.gov (United States)

    Hygge, S

    1976-06-01

    Four groups with 16 observers each participated in a differential, vicarious conditioning experiment with skin conductance responses as the dependent variable. The information available to the observer about the model's unconditioned stimulus and response was varied in a 2 X 2 factorial design. Results clearly showed that information about the model's unconditioned stimulus (a high or low dB level) was not necessary for vicarious instigation, but that information about the unconditioned response (a high or low emotional aversiveness) was necessary. Data for conditioning of responses showed almost identical patterns to those for vicarious instigation. To explain the results, a distinction between factors necessary for the development and elicitation of vicariously instigated responses was introduced, and the effectiveness of information about the model's response on the elicitation of vicariously instigated responses was considered in terms of an expansion of Bandura's social learning theory.

  17. Consistent haul road condition monitoring by means of vehicle response normalisation with Gaussian processes

    CSIR Research Space (South Africa)

    Heyns, T

    2012-12-01

    Full Text Available Suboptimal haul road management policies such as routine, periodic and urgent maintenance may result in unnecessary cost, both to roads and vehicles. A recent idea is to continually access haul road condition based on measured vehicle response...

  18. Differential modulation of auditory responses to attended and unattended speech in different listening conditions.

    Science.gov (United States)

    Kong, Ying-Yee; Mullangi, Ala; Ding, Nai

    2014-10-01

    This study investigates how top-down attention modulates neural tracking of the speech envelope in different listening conditions. In the quiet conditions, a single speech stream was presented and the subjects paid attention to the speech stream (active listening) or watched a silent movie instead (passive listening). In the competing speaker (CS) conditions, two speakers of opposite genders were presented diotically. Ongoing electroencephalographic (EEG) responses were measured in each condition and cross-correlated with the speech envelope of each speaker at different time lags. In quiet, active and passive listening resulted in similar neural responses to the speech envelope. In the CS conditions, however, the shape of the cross-correlation function was remarkably different between the attended and unattended speech. The cross-correlation with the attended speech showed stronger N1 and P2 responses but a weaker P1 response compared to the cross-correlation with the unattended speech. Furthermore, the N1 response to the attended speech in the CS condition was enhanced and delayed compared with the active listening condition in quiet, while the P2 response to the unattended speaker in the CS condition was attenuated compared with the passive listening in quiet. Taken together, these results demonstrate that top-down attention differentially modulates envelope-tracking neural activity at different time lags and suggest that top-down attention can both enhance the neural responses to the attended sound stream and suppress the responses to the unattended sound stream. Copyright © 2014 Elsevier B.V. All rights reserved.

  19. DEVELOPMENT OF THE CONCEPT OF CORPORATE SOCIAL RESPONSIBILITY IN TRADE UNDER CONDITIONS OF MARKET GLOBALISATION

    OpenAIRE

    Svetlana Sokolov Mladenovic, Djordje Cuzovic,

    2015-01-01

    Under contemporary business conditions, market globalisation has become inevitable. Such relationships on the market make trade companies use different means to acquire and maintain long-term competitive advantage. One of them is the concept of corporate social responsibility, which is, under conditions of globalisation, seen as a redesign of the classic marketing concept. The aim of this paper is to highlight the development of corporate social responsibility in trade, in the context of mark...

  20. Extinction of Conditioned Responses to Methamphetamine-Associated Stimuli in Healthy Humans.

    Science.gov (United States)

    Cavallo, Joel S; Ruiz, Nicholas A; de Wit, Harriet

    2016-07-01

    Contextual stimuli present during drug experiences become associated with the drug through Pavlovian conditioning and are thought to sustain drug-seeking behavior. Thus, extinction of conditioned responses is an important target for treatment. To date, acquisition and extinction to drug-paired cues have been studied in animal models or drug-dependent individuals, but rarely in non-drug users. We have recently developed a procedure to study acquisition of conditioned responses after single doses of methamphetamine (MA) in healthy volunteers. Here, we examined extinction of these responses and their persistence after conditioning. Healthy adults (18-35 years; N = 20) received two pairings of audio-visual stimuli with MA (20 mg oral) or placebo. Responses to stimuli were assessed before and after conditioning, using three tasks: behavioral preference, attentional bias, and subjective "liking." Subjects exhibited behavioral preference for the drug-paired stimuli at the first post-conditioning test, but this declined rapidly on subsequent extinction tests. They also exhibited a bias to initially look towards the drug-paired stimuli at the first post-test session, but not thereafter. Subjects who experienced more positive subjective drug effects during conditioning exhibited a smaller decline in preference during the extinction phase. Further, longer inter-session intervals during the extinction phase were associated with less extinction of the behavioral preference measure. Conditioned responses after two pairings with MA extinguish quickly, and are influenced by both subjective drug effects and the extinction interval. Characterizing and refining this conditioning procedure will aid in understanding the acquisition and extinction processes of drug-related conditioned responses in humans.

  1. Differences of accommodative responses between two eyes under binocular viewing condition mediated by polarizing glasses

    Directory of Open Access Journals (Sweden)

    Rui-Qing Wang

    2016-04-01

    Full Text Available AIM:To study the differences of accommodative responses between the two eyes under 3 different polarized viewing conditions. METHODS:Fifteen volunteers with emmetrope were recruited into this study(aged 18~38, 6 males and 9 females. Three different viewing conditions were set up by using polarizing glasses and liquid crystal display:(1right eye could see the visual target on the screen, but left eye cannot see it;(2left eye could see the visual target on the screen, but right eye cannot see it;(3both eyes could see the target. Accommodative responses were measured by infrared auto-refractor when fixating at the target at 5, 2, 1, 0.5 and 0.33m under the above 3 viewing conditions. The differences of accommodative responses under different viewing conditions were compared by using variance analysis of repeated measuring and t test. RESULTS:Significant differences of accommodative responses between the two eyes were found under condition(1and(2at all the fixating distance. The accommodative responses in used eyes which can see the visual target were higher than in non-used eyes which cannot see the visual target(PP>0.05. CONCLUSION:Ciliary muscles in the used eyes were more relatively tonic than non-used eyes under binocular open viewing condition. The imbalance of accommodative responses between two eyes may be one of the risk factors resulting into the occurrence of myopia.

  2. Responses in young Quercus petraea: coppices and standards under favourable and drought conditions

    Czech Academy of Sciences Publication Activity Database

    Stojanović, Marko; Čater, M.; Pokorný, Radek

    2016-01-01

    Roč. 76, jan (2016), s. 127-136 ISSN 1641-1307 R&D Projects: GA MŠk(CZ) EE2.3.20.0267 Institutional support: RVO:67179843 Keywords : coppice * standards * comparison * photosynthetic response * quantum yield * light conditions * drought response Subject RIV: EF - Botanics Impact factor: 0.776, year: 2016

  3. A Model-Free Diagnostic for Single-Peakedness of Item Responses Using Ordered Conditional Means

    Science.gov (United States)

    Polak, Marike; De Rooij, Mark; Heiser, Willem J.

    2012-01-01

    In this article we propose a model-free diagnostic for single-peakedness (unimodality) of item responses. Presuming a unidimensional unfolding scale and a given item ordering, we approximate item response functions of all items based on ordered conditional means (OCM). The proposed OCM methodology is based on Thurstone & Chave's (1929) "criterion…

  4. Electrodermal responses during appetitive conditioning are sensitive to contingency instruction ambiguity.

    Science.gov (United States)

    van den Akker, Karolien; Nederkoorn, Chantal; Jansen, Anita

    2017-08-01

    Studies on human appetitive conditioning using food rewards can benefit from including psychophysiological outcome measures. The present study tested whether the skin conductance response can function as a measure of differential responding in an appetitive conditioning paradigm including an acquisition and extinction phase, and examined which time window during a trial is most sensitive to conditioning effects. As a secondary aim, the effects of ambiguous vs. non-ambiguous contingency instructions on conditioned responses (skin conductance responses, US expectancies, chocolate desires, and CS evaluations) were assessed. Results indicated differential skin conductance responses in an anticipatory time window and during unexpected omission of the US in early extinction. Interestingly however, anticipatory responses were only found for participants who received ambiguous contingency instructions - possibly indicating a call for additional processing resources in response to the ambiguous CS+. Further, ambiguous instructions slowed the extinction of US expectancies but did not influence chocolate desires and CS evaluations. It is concluded that skin conductance can function as a sensitive measure of differential responding in appetitive conditioning, though its sensitivity might depend on the specific task context. Copyright © 2017 Elsevier B.V. All rights reserved.

  5. Shipping container response to severe highway and railway accident conditions: Main report

    International Nuclear Information System (INIS)

    Fischer, L.E.; Chou, C.K.; Gerhard, M.A.; Kimura, C.Y.; Martin, R.W.; Mensing, R.W.; Mount, M.E.; Witte, M.C.

    1987-02-01

    This report describes a study performed by the Lawrence Livermore National Laboratory to evaluate the level of safety provided under severe accident conditions during the shipment of spent fuel from nuclear power reactors. The evaluation is performed using data from real accident histories and using representative truck and rail cask models that likely meet 10 CFR 71 regulations. The responses of the representative casks are calculated for structural and thermal loads generated by severe highway and railway accident conditions. The cask responses are compared with those responses calculated for the 10 CFR 71 hypothetical accident conditions. By comparing the responses it is determined that most highway and railway accident conditions fall within the 10 CFR 71 hypothetical accident conditions. For those accidents that have higher responses, the probabilities anf potential radiation exposures of the accidents are compared with those identified by the assessments made in the ''Final Environmental Statement on the Transportation of Radioactive Material by Air and other Modes,'' NUREG-0170. Based on this comparison, it is concluded that the radiological risks from spent fuel under severe highway and railway accident conditions as derived in this study are less than risks previously estimated in the NUREG-0170 document

  6. Dissociating basal forebrain and medial temporal amnesic syndromes: insights from classical conditioning.

    Science.gov (United States)

    Myer, Catherine E; Bryant, Deborah; DeLuca, John; Gluck, Mark A

    2002-01-01

    In humans, anterograde amnesia can result from damage to the medial temporal (MT) lobes (including hippocampus), as well as to other brain areas such as basal forebrain. Results from animal classical conditioning studies suggest that there may be qualitative differences in the memory impairment following MT vs. basal forebrain damage. Specifically, delay eyeblink conditioning is spared after MT damage in animals and humans, but impaired in animals with basal forebrain damage. Recently, we have likewise shown delay eyeblink conditioning impairment in humans with amnesia following anterior communicating artery (ACoA) aneurysm rupture, which damages the basal forebrain. Another associative learning task, a computer-based concurrent visual discrimination, also appears to be spared in MT amnesia while ACoA amnesics are slower to learn the discriminations. Conversely, animal and computational models suggest that, even though MT amnesics may learn quickly, they may learn qualitatively differently from controls, and these differences may result in impaired transfer when familiar information is presented in novel combinations. Our initial data suggests such a two-phase learning and transfer task may provide a double dissociation between MT amnesics (spared initial learning but impaired transfer) and ACoA amnesics (slow initial learning but spared transfer). Together, these emerging data suggest that there are subtle but dissociable differences in the amnesic syndrome following damage to the MT lobes vs. basal forebrain, and that these differences may be most visible in non-declarative tasks such as eyeblink classical conditioning and simple associative learning.

  7. Global Transcriptional Responses to Osmotic, Oxidative, and Imipenem Stress Conditions in Pseudomonas putida

    DEFF Research Database (Denmark)

    Bojanovic, Klara; D'Arrigo, Isotta; Long, Katherine

    2017-01-01

    functional roles in the cellular response to stress conditions. The data show a larger fraction of differentially expressed sRNAs than of mRNAs with >5-fold expression changes. The work provides detailed insights into the mechanisms through which P. putida responds to different stress conditions...... intergenic and antisense transcripts, were detected, increasing the number of identified sRNA transcripts in the strain by a factor of 10. Unique responses to each type of stress are documented, including both the extent and dynamics of the gene expression changes. The work adds rich detail to previous......Bacteria cope with and adapt to stress by modulating gene expression in response to specific environmental cues. In this study, the transcriptional response of Pseudomonas putida KT2440 to osmotic, oxidative, and imipenem stress conditions at two time points was investigated via identification...

  8. Appeals to consumer responsibility and improving structural conditions as means to promote sustainable consumer behavior

    DEFF Research Database (Denmark)

    Thøgersen, John

    for their acts or (b) structural conditions determined by governments? In field experiments with large samples of ordinary consumers, the behavioral effects of perceptions of responsibility/personal moral norms and of altering an important structural condition are quantified by measuring a relevant behavior......-developed public transit service. The results suggest that there is often more to gain from changing structural conditions to be more facilitating for the desired behavior than from a campaign targeting consumer feelings of responsibility.......Environmental policy-makers increasingly emphasize consumers' responsibility for environmental side effects of their acts, but is this justified? This paper investigates which is the most important limiting factor for sustainable consumption: (a) the extent to which consumers assume responsibility...

  9. Autoshaping in the rat: conditioned licking response to a stimulus that signals sucrose reinforcement.

    Science.gov (United States)

    Reilly, Steve; Grutzmacher, Richard P.

    2002-07-31

    The present experiments were designed to determine if repeated presentations of an empty sipper tube (the conditioned stimulus or CS) with the response-independent delivery of a sucrose solution (the unconditioned stimulus or US) from a second spout results in the development of Pavlovian conditioned responding. In Experiment 1, rats in the experimental condition received paired CS-US presentations whereas subjects in the control condition were exposed to random presentations of CS and US. In Experiment 2, an additional control condition (CS alone) was included and, to encourage generalized responding between the US and CS, the CS tube was filled with water for all groups. The results of both experiments indicate that the CS-directed responding in the paired CS-US condition was Pavlovian in nature. Thus, the present procedure serves as an autoshaping task in which conditioned licking is generated.

  10. Pavlovian drug-sickness pairings result in the conditioning of an antisickness response.

    Science.gov (United States)

    Lett, B T

    1983-10-01

    After a drug conditioned stimulus (CS) has been injected prior to lithium chloride as the unconditioned stimulus (US) on five occasions, the drug CS becomes able to evoke a conditioned antisickness response (CAR). This CAR is implied by the finding that the CS drug mitigates the conditioned saccharin aversion produced by lithium when it is administered in the interval between saccharin consumption and lithium injection. The following drugs were tested and are listed in approximate order of their effectiveness in producing a conditioned antisickness effect: pentobarbital, ethanol, morphine, amphetamine, and chlordiazepoxide.

  11. Maternal body condition influences magnitude of anti-predator response in offspring.

    Science.gov (United States)

    Bennett, Amanda M; Murray, Dennis L

    2014-11-07

    Organisms exhibit plasticity in response to their environment, but there is large variation even within populations in the expression and magnitude of response. Maternal influence alters offspring survival through size advantages in growth and development. However, the relationship between maternal influence and variation in plasticity in response to predation risk is unknown. We hypothesized that variation in the magnitude of plastic responses between families is at least partly due to maternal provisioning and examined the relationship between maternal condition, egg provisioning and magnitude of plastic response to perceived predation risk (by dragonfly larvae: Aeshna spp.) in northern leopard frogs (Lithobates pipiens). Females in better body condition tended to lay more (clutch size) larger (egg diameter) eggs. Tadpoles responded to predation risk by increasing relative tail depth (morphology) and decreasing activity (behaviour). We found a positive relationship between morphological effect size and maternal condition, but no relationship between behavioural effect size and maternal condition. These novel findings suggest that limitations imposed by maternal condition can constrain phenotypic variation, ultimately influencing the capacity of populations to respond to environmental change. © 2014 The Author(s) Published by the Royal Society. All rights reserved.

  12. Heart rate response to fear conditioning and virtual reality in subthreshold PTSD.

    Science.gov (United States)

    Roy, Michael J; Costanzo, Michelle E; Jovanovic, Tanja; Leaman, Suzanne; Taylor, Patricia; Norrholm, Seth D; Rizzo, Albert A

    2013-01-01

    Posttraumatic stress disorder (PTSD) is a significant health concern for U.S. military service members (SMs) returning from Afghanistan and Iraq. Early intervention to prevent chronic disability requires greater understanding of subthreshold PTSD symptoms, which are associated with impaired physical health, mental health, and risk for delayed onset PTSD. We report a comparison of physiologic responses for recently deployed SMs with high and low subthreshold PTSD symptoms, respectively, to a fear conditioning task and novel virtual reality paradigm (Virtual Iraq). The high symptom group demonstrated elevated heart rate (HR) response during fear conditioning. Virtual reality sequences evoked significant HR responses which predicted variance of the PTSD Checklist-Military Version self-report. Our results support the value of physiologic assessment during fear conditioning and combat-related virtual reality exposure as complementary tools in detecting subthreshold PTSD symptoms in Veterans.

  13. The rights and responsibilities of citizenship for service users: some terms and conditions apply.

    Science.gov (United States)

    Hamer, H P; Finlayson, M

    2015-11-01

    What is known about the subject? Citizenship is an important yet largely overlooked concept within psychiatric and mental health nursing practice Many service users are subject to legally mandated restrictions that place conditions on their rights and responsibilities as citizens. What this paper adds to existing knowledge? Even though service users have legal status as citizens, they continue to experience many conditions on their rights and responsibilities. Concerns about services users' trustworthiness and doubts about their levels of insight impact on their status as full citizens. What are the implications for practice? Nurses' understandings of the conditions placed on the citizenship rights and responsibilities of service users will ensure inclusive and less restrictive care and treatment Integration of the principles of therapeutic reciprocity and procedural justice within practice will help nurses balance both the rights of services users and legal restrictions on their liberty and autonomy Service users have long been lobbying for equal participation as citizens, yet citizenship is an important and largely overlooked concept within nursing education and practice. The study explored service users' understandings of their rights and responsibilities of citizenship and the conditions placed on these. A total of 17 service users participated in semi-structured interviews. Isin's theory of the content of citizenship was used to analyze the data using a framework approach. Service users experience conditional citizenship that includes barriers to their participation and their rights and responsibilities that others in society enjoy. When the world of the service user is constructed through the language of the biomedical model, nurses may unwittingly reinforce psychiatric labels and thus perpetuate the stereotype that service users lack the competence to fully enact their rights and responsibilities. When providing care, nurses should incorporate the notion of

  14. Equal pain – Unequal fear response: Enhanced susceptibility of tooth pain to fear conditioning

    Directory of Open Access Journals (Sweden)

    Michael Lukas Meier

    2014-07-01

    Full Text Available Experimental fear conditioning in humans is widely used as a model to investigate the neural basis of fear learning and to unravel the pathogenesis of anxiety disorders. It has been observed that fear conditioning depends on stimulus salience and subject vulnerability to fear. It is further known that the prevalence of dental-related fear and phobia is exceedingly high in the population. Dental phobia is unique as no other body part is associated with a specific phobia. Therefore, we hypothesized that painful dental stimuli exhibit an enhanced susceptibility to fear conditioning when comparing to equal perceived stimuli applied to other body sites. Differential susceptibility to pain-related fear was investigated by analyzing responses to an unconditioned stimulus (UCS applied to the right maxillary canine (UCS-c versus the right tibia (UCS-t. For fear conditioning, UCS-c and USC-t consisted of painful electric stimuli, carefully matched at both application sites for equal intensity and quality perception. UCSs were paired to simple geometrical forms which served as conditioned stimuli (CS+. Unpaired CS+ were presented for eliciting and analyzing conditioned fear responses. Outcome parameter were 1 skin conductance changes and 2 time-dependent brain activity (BOLD responses in fear-related brain regions such as the amygdala, anterior cingulate cortex, insula, thalamus, orbitofrontal cortex and medial prefrontal cortex.A preferential susceptibility of dental pain to fear conditioning was observed, reflected by heightened skin conductance responses and enhanced time-dependent brain activity (BOLD responses in the fear network. For the first time, this study demonstrates fear-related neurobiological mechanisms that point towards a superior conditionability of tooth pain. Beside traumatic dental experiences our results offer novel evidence that might explain the high prevalence of dental-related fears in the population.

  15. Effect of brewing conditions on antioxidant properties of rosehip tea beverage: study by response surface methodology.

    Science.gov (United States)

    İlyasoğlu, Huri; Arpa, Tuba Eda

    2017-10-01

    The aim of this study was to investigate the effects of brewing conditions (infusion time and temperature) on the antioxidant properties of rosehip tea beverage. The ascorbic acid content, total phenolic content (TPC), and ferric reducing antioxidant power (FRAP) of rosehip tea beverage were analysed. A two-factor and three-level central composite design was applied to evaluate the effects of the variables on the responses. The best quadratic models were obtained for all responses. The generated models were validated under the optimal conditions. At the optimal conditions, the rosehip tea beverage had 3.15 mg 100 mL -1 of ascorbic acid, 61.44 mg 100 mL -1 of TPC, and 2591 µmol of FRAP. The best brewing conditions for the rosehip tea beverage were found to be an infusion time of 6-8 min at temperatures of 84-86 °C.

  16. A radioactive waste transportation package monitoring system for normal transport and accident emergency response conditions

    International Nuclear Information System (INIS)

    Brown, G.S.; Cashwell, J.W.; Apple, M.L.

    1993-01-01

    This paper addresses spent fuel and high level waste transportation history and prospects, discusses accident histories of radioactive material transport, discusses emergency responder needs and provides a general description of the Transportation Intelligent Monitoring System (TRANSIMS) design. The key objectives of the monitoring system are twofold: (1) to facilitate effective emergency response to accidents involving a radioactive waste transportation package, while minimizing risk to the public and emergency first-response personnel, and (2) to allow remote monitoring of transportation vehicle and payload conditions to enable research into radioactive material transportation for normal and accident conditions. (J.P.N.)

  17. Declarative Event-Based Workflow as Distributed Dynamic Condition Response Graphs

    DEFF Research Database (Denmark)

    Hildebrandt, Thomas; Mukkamala, Raghava Rao

    2010-01-01

    We present Dynamic Condition Response Graphs (DCR Graphs) as a declarative, event-based process model inspired by the workflow language employed by our industrial partner and conservatively generalizing prime event structures. A dynamic condition response graph is a directed graph with nodes repr...... exemplify the use of distributed DCR Graphs on a simple workflow taken from a field study at a Danish hospital, pointing out their flexibility compared to imperative workflow models. Finally we provide a mapping from DCR Graphs to Buchi-automata....

  18. [SOS response of DNA repair and genetic cell instability under hypoxic conditions].

    Science.gov (United States)

    Vasil'eva, S V; Strel'tsova, D A

    2011-01-01

    The SOS DNA repair pathway is induced in E. coli as a multifunctional cell response to a wide variety of signals: UV, X or gamma-irradiation, mitomycin C or nalidixic acid treatment, thymine starvation, etc. Triggering of the system can be used as a general and early sign of DNA damage. Additionally, the SOS-response is known to be an "error-prone" DNA repair pathway and one of the sources of genetic instability. Hypoxic conditions are established to be the major factor of genetic instability as well. In this paper we for the first time studied the SOS DNA repair response under hypoxic conditions induced by the well known aerobic SOS-inducers. The SOS DNA repair response was examined as a reaction of E. coli PQ37 [sfiA::lacZ] cells to UVC, NO-donating agents and 4NQO. Here we provide evidence that those agents were able to induce the SOS DNA repair response in E. coli at anaerobic growth conditions. The process does not depend on the transcriptional activity of the universal protein of E. col anaerobic growth Fnr [4Fe-4S]2+ or can not be referred to as an indicator of genetic instability in hypoxic conditions.

  19. Impact of HSCT conditioning and glucocorticoid dose on exercise adherence and response

    OpenAIRE

    Wiskemann, Joachim; Herzog, Benedikt; Kuehl, Rea; Schmidt, Martina E.; Steindorf, Karen; Schwerdtfeger, Rainer; Dreger, Peter; Bohus, Martin

    2017-01-01

    Abstract: Purpose: Evidence from randomized controlled trials (RCT) that exercise interventions have beneficial effects in patients undergoing allogeneic hematopoietic stem cell transplantation (allo-HSCT) is growing. However, intensive chemotherapy conditioning and glucocorticoid (GC) treatment is always part of an allo-HSCT and possibly affect exercise adherence and training response. Therefore, we aimed to examine whether various conditioning protocols or different doses of GC treatment af...

  20. Exposures to Conditioned Flavours with Different Hedonic Values Induce Contrasted Behavioural and Brain Responses in Pigs

    OpenAIRE

    Clouard, Caroline; Jouhanneau, Mélanie; Meunier-Salaün, Marie-Christine; Malbert, Charles-Henri; Val-Laillet, David

    2012-01-01

    This study investigated the behavioural and brain responses towards conditioned flavours with different hedonic values in juvenile pigs. Twelve 30-kg pigs were given four three-day conditioning sessions: they received three different flavoured meals paired with intraduodenal (i.d.) infusions of 15% glucose (F(Glu)), lithium chloride (F(LiCl)), or saline (control treatment, F(NaCl)). One and five weeks later, the animals were subjected to three two-choice feeding tests without reinforcement to...

  1. Ice Storage Air-Conditioning System Simulation with Dynamic Electricity Pricing: A Demand Response Study

    Directory of Open Access Journals (Sweden)

    Chi-Chun Lo

    2016-02-01

    Full Text Available This paper presents an optimal dispatch model of an ice storage air-conditioning system for participants to quickly and accurately perform energy saving and demand response, and to avoid the over contact with electricity price peak. The schedule planning for an ice storage air-conditioning system of demand response is mainly to transfer energy consumption from the peak load to the partial-peak or off-peak load. Least Squares Regression (LSR is used to obtain the polynomial function for the cooling capacity and the cost of power consumption with a real ice storage air-conditioning system. Based on the dynamic electricity pricing, the requirements of cooling loads, and all technical constraints, the dispatch model of the ice-storage air-conditioning system is formulated to minimize the operation cost. The Improved Ripple Bee Swarm Optimization (IRBSO algorithm is proposed to solve the dispatch model of the ice storage air-conditioning system in a daily schedule on summer. Simulation results indicate that reasonable solutions provide a practical and flexible framework allowing the demand response of ice storage air-conditioning systems to demonstrate the optimization of its energy savings and operational efficiency and offering greater energy efficiency.

  2. Orbitofrontal participation in sign- and goal-tracking conditioned responses: Effects of nicotine.

    Science.gov (United States)

    Stringfield, Sierra J; Palmatier, Matthew I; Boettiger, Charlotte A; Robinson, Donita L

    2017-04-01

    Pavlovian conditioned stimuli can acquire incentive motivational properties, and this phenomenon can be measured in animals using Pavlovian conditioned approach behavior. Drugs of abuse can influence the expression of this behavior, and nicotine in particular exhibits incentive amplifying effects. Both conditioned approach behavior and drug abuse rely on overlapping corticolimbic circuitry. We hypothesize that the orbitofrontal cortex (OFC) regulates conditioned approach, and that one site of nicotine action is in the OFC where it reduces cortical output. To test this, we repeatedly exposed rats to 0.4 mg/kg nicotine (s.c.) during training and then pharmacologically inactivated the lateral OFC or performed in vivo electrophysiological recordings of lateral OFC neurons in the presence or absence of nicotine. In Experiment 1, animals were trained in a Pavlovian conditioning paradigm and behavior was evaluated after inactivation of the OFC by microinfusion of the GABA agonists baclofen and muscimol. In Experiment 2, we monitored phasic firing of OFC neurons during Pavlovian conditioning sessions. Nicotine reliably enhanced conditioned responding to the conditioned cue, and inactivation of the OFC reduced conditioned responding, especially the sign-tracking response. OFC neurons exhibited phasic excitations to cue presentation and during goal tracking, and nicotine acutely blunted this phasic neuronal firing. When nicotine was withheld, both conditioned responding and phasic firing in the OFC returned to the level of controls. These results suggest that the OFC is recruited for the expression of conditioned responses, and that nicotine acutely influences this behavior by reducing phasic firing in the OFC. Copyright © 2016 Elsevier Ltd. All rights reserved.

  3. Global Transcriptional Responses to Osmotic, Oxidative, and Imipenem Stress Conditions in Pseudomonas putida.

    Science.gov (United States)

    Bojanovič, Klara; D'Arrigo, Isotta; Long, Katherine S

    2017-04-01

    Bacteria cope with and adapt to stress by modulating gene expression in response to specific environmental cues. In this study, the transcriptional response of Pseudomonas putida KT2440 to osmotic, oxidative, and imipenem stress conditions at two time points was investigated via identification of differentially expressed mRNAs and small RNAs (sRNAs). A total of 440 sRNA transcripts were detected, of which 10% correspond to previously annotated sRNAs, 40% to novel intergenic transcripts, and 50% to novel transcripts antisense to annotated genes. Each stress elicits a unique response as far as the extent and dynamics of the transcriptional changes. Nearly 200 protein-encoding genes exhibited significant changes in all stress types, implicating their participation in a general stress response. Almost half of the sRNA transcripts were differentially expressed under at least one condition, suggesting possible functional roles in the cellular response to stress conditions. The data show a larger fraction of differentially expressed sRNAs than of mRNAs with >5-fold expression changes. The work provides detailed insights into the mechanisms through which P. putida responds to different stress conditions and increases understanding of bacterial adaptation in natural and industrial settings. IMPORTANCE This study maps the complete transcriptional response of P. putida KT2440 to osmotic, oxidative, and imipenem stress conditions at short and long exposure times. Over 400 sRNA transcripts, consisting of both intergenic and antisense transcripts, were detected, increasing the number of identified sRNA transcripts in the strain by a factor of 10. Unique responses to each type of stress are documented, including both the extent and dynamics of the gene expression changes. The work adds rich detail to previous knowledge of stress response mechanisms due to the depth of the RNA sequencing data. Almost half of the sRNAs exhibit significant expression changes under at least one

  4. Growth condition dependency is the major cause of non-responsiveness upon genetic perturbation.

    Directory of Open Access Journals (Sweden)

    Saman Amini

    Full Text Available Investigating the role and interplay between individual proteins in biological processes is often performed by assessing the functional consequences of gene inactivation or removal. Depending on the sensitivity of the assay used for determining phenotype, between 66% (growth and 53% (gene expression of Saccharomyces cerevisiae gene deletion strains show no defect when analyzed under a single condition. Although it is well known that this non-responsive behavior is caused by different types of redundancy mechanisms or by growth condition/cell type dependency, it is not known what the relative contribution of these different causes is. Understanding the underlying causes of and their relative contribution to non-responsive behavior upon genetic perturbation is extremely important for designing efficient strategies aimed at elucidating gene function and unraveling complex cellular systems. Here, we provide a systematic classification of the underlying causes of and their relative contribution to non-responsive behavior upon gene deletion. The overall contribution of redundancy to non-responsive behavior is estimated at 29%, of which approximately 17% is due to homology-based redundancy and 12% is due to pathway-based redundancy. The major determinant of non-responsiveness is condition dependency (71%. For approximately 14% of protein complexes, just-in-time assembly can be put forward as a potential mechanistic explanation for how proteins can be regulated in a condition dependent manner. Taken together, the results underscore the large contribution of growth condition requirement to non-responsive behavior, which needs to be taken into account for strategies aimed at determining gene function. The classification provided here, can also be further harnessed in systematic analyses of complex cellular systems.

  5. Cell-cycle distributions and radiation responses of Chinese hamster cells cultured continuously under hypoxic conditions

    International Nuclear Information System (INIS)

    Tokita, N.; Carpenter, S.G.; Raju, M.R.

    1984-01-01

    Cell-cycle distributions were measured by flow cytometry for Chinese hamster (CHO) cells cultured continuously under hypoxic conditions. DNA histograms showed an accumulation of cells in the early S phase followed by a traverse delay through the S phase, and a G 2 block. During hypoxic culturing, cell viability decreased rapidly to less than 0.1% at 120 h. Radiation responses for cells cultured under these conditions showed an extreme radioresistance at 72 h. Results suggest that hypoxia induces a condition similar to cell synchrony which itself changes the radioresistance of hypoxic cells. (author)

  6. Robust hippocampal responsivity during retrieval of consolidated associative memory.

    Science.gov (United States)

    Hattori, Shoai; Chen, Lillian; Weiss, Craig; Disterhoft, John F

    2015-05-01

    A contentious point in memory research is whether or not the hippocampus plays a time-limited role in the consolidation of declarative memories. A widely held view is that declarative memories are initially encoded in the hippocampus, then transferred to the neocortex for long-term storage. Alternate views argue instead that the hippocampus continues to play a role in remote memory recall. These competing theories are largely based on human amnesic and animal lesion/inactivation studies. However, in vivo electrophysiological evidence supporting these views is scarce. Given that other studies examining the role of the hippocampus in remote memory retrieval using lesion and imaging techniques in human and animal models have provided mixed results, it would be particularly useful to gain insight at the in vivo electrophysiological level. Here we report hippocampal single-neuron and theta activity recorded longitudinally during acquisition and remote retrieval of trace eyeblink conditioning. Results from conditioned rabbits were compared to those obtained from yoked pseudo-conditioned control rabbits. Results reveal continued learning-specific hippocampal activity one month after initial acquisition of the task. Our findings yield insight into the normal physiological responses of the hippocampus during memory processes and provide compelling in vivo electrophysiological evidence that the hippocampus is involved in both acquisition and retrieval of consolidated memories. © 2014 The Authors Hippocampus Published by Wiley Periodicals, Inc.

  7. Implicit misattribution of evaluative responses: contingency-unaware evaluative conditioning requires simultaneous stimulus presentations.

    Science.gov (United States)

    Hütter, Mandy; Sweldens, Steven

    2013-08-01

    Recent research has shown that evaluative conditioning (EC) procedures can change attitudes without participants' awareness of the contingencies between conditioned and unconditioned stimuli (Hütter, Sweldens, Stahl, Unkelbach, & Klauer, 2012). We present a theoretical explanation and boundary condition for the emergence of unaware EC effects based on the implicit misattribution of evaluative responses from unconditioned to conditioned stimuli. We hypothesize that such misattribution is only possible when conditioned and unconditioned stimuli are perceived simultaneously. Therefore we manipulate the simultaneity of the stimulus presentations and apply a process dissociation procedure to distinguish contingency-aware from contingency-unaware EC effects. A multinomial model indicates that with sequential presentations, EC effects do not occur without contingency awareness. However, unaware EC effects do occur with simultaneous presentations. The findings support dual-process theories of learning. PsycINFO Database Record (c) 2013 APA, all rights reserved.

  8. Response in atmospheric circulation and sources of Greenland precipitation to glacial boundary conditions

    DEFF Research Database (Denmark)

    Langen, Peter Lang; Vinther, Bo Møllesøe

    2009-01-01

    The response in northern hemisphere atmospheric circulation and the resulting changes in moisture sources for Greenland precipitation to glacial boundary conditions are studied in NCAR's CCM3 atmospheric general circulation model fitted with a moisture tracking functionality. We employ both...... seasonality, condensation temperatures and source temperatures are assessed. Udgivelsesdato: June 2009...

  9. Effect of the foundation stiffness on the response of a seismically isolated tank under SSE conditions

    NARCIS (Netherlands)

    Esposito, G.; Courage, W.

    2003-01-01

    This paper presents the results of a feasibility study of a seismic isolated 120.000 m3 LNG tank. A simple model was used to evaluate the seismic response of the isolated tank under Safe Shutdown Earthquake conditions. The frequency dependent dynamic stiffness of the foundation was

  10. Contracts for Cross-organizational Workflows as Timed Dynamic Condition Response Graphs

    DEFF Research Database (Denmark)

    Hildebrandt, Thomas; Mukkamala, Raghava Rao; Slaats, Tijs

    2013-01-01

    We conservatively extend the declarative Dynamic Condition Response (DCR) Graph process model, introduced in the PhD thesis of the second author, to allow for discrete time deadlines. We prove that safety and liveness properties can be verified by mapping finite timed DCR Graphs to finite state...

  11. Digitalising the General Data Protection Regulation with Dynamic Condition Response Graphs

    DEFF Research Database (Denmark)

    Heuck, Emil; Hildebrandt, Thomas; Kiærulff Lerche, Rasmus

    2017-01-01

    We describe how the declarative Dynamic Condition Response (DCR) Graphs proces notation can be used to digitalise the General Data Protection Regulation (GDPR) and make a first evaluation to what extend the formalisation and associated tool for end-user modelling and simulation can be used to cla...

  12. Accuracy of circadian entrainment under fluctuating light conditions : Contributions of phase and period responses

    NARCIS (Netherlands)

    Beersma, DGM; Daan, S; Hut, RA

    The accuracy with which a circadian pacemaker can entrain to an environmental 24-h zeitgeber signal depends on (a) characteristics of the entraining signal and (b) response characteristics and intrinsic stability of the pacemaker itself. Position of the sun, weather conditions, shades, and

  13. The effect of conditional probability of chord progression on brain response: an MEG study.

    Directory of Open Access Journals (Sweden)

    Seung-Goo Kim

    Full Text Available BACKGROUND: Recent electrophysiological and neuroimaging studies have explored how and where musical syntax in Western music is processed in the human brain. An inappropriate chord progression elicits an event-related potential (ERP component called an early right anterior negativity (ERAN or simply an early anterior negativity (EAN in an early stage of processing the musical syntax. Though the possible underlying mechanism of the EAN is assumed to be probabilistic learning, the effect of the probability of chord progressions on the EAN response has not been previously explored explicitly. METHODOLOGY/PRINCIPAL FINDINGS: In the present study, the empirical conditional probabilities in a Western music corpus were employed as an approximation of the frequencies in previous exposure of participants. Three types of chord progression were presented to musicians and non-musicians in order to examine the correlation between the probability of chord progression and the neuromagnetic response using magnetoencephalography (MEG. Chord progressions were found to elicit early responses in a negatively correlating fashion with the conditional probability. Observed EANm (as a magnetic counterpart of the EAN component responses were consistent with the previously reported EAN responses in terms of latency and location. The effect of conditional probability interacted with the effect of musical training. In addition, the neural response also correlated with the behavioral measures in the non-musicians. CONCLUSIONS/SIGNIFICANCE: Our study is the first to reveal the correlation between the probability of chord progression and the corresponding neuromagnetic response. The current results suggest that the physiological response is a reflection of the probabilistic representations of the musical syntax. Moreover, the results indicate that the probabilistic representation is related to the musical training as well as the sensitivity of an individual.

  14. Pseudomonas putida response in membrane bioreactors under salicylic acid-induced stress conditions

    Energy Technology Data Exchange (ETDEWEB)

    Collado, Sergio; Rosas, Irene; González, Elena; Gutierrez-Lavin, Antonio; Diaz, Mario, E-mail: mariodiaz@uniovi.es

    2014-02-01

    Highlights: • MBR under feed-induced stress conditions: starvation and changing feeding conditions. • High capacity of MBR to withstand high variations in feed loads. • Slow biofilm formation under starvation conditions during the first days. • Observed growth of P. putida for substrate to microorganism ratio higher than 0.6 g/g. • Maximum specific growth rate and growth yield values of around 37.5 h{sup −1} and 0.5 g/g. - Abstract: Starvation and changing feeding conditions are frequently characteristics of wastewater treatment plants. They are typical causes of unsteady-state operation of biological systems and provoke cellular stress. The response of a membrane bioreactor functioning under feed-induced stress conditions is studied here. In order to simplify and considerably amplify the response to stress and to obtain a reference model, a pure culture of Pseudomonas putida was selected instead of an activated sludge and a sole substrate (salicylic acid) was employed. The system degraded salicylic acid at 100–1100 mg/L with a high level of efficiency, showed rapid acclimation without substrate or product inhibition phenomena and good stability in response to unsteady states caused by feed variations. Under starvation conditions, specific degradation rates of around 15 mg/g h were achieved during the adaptation of the biomass to the new conditions and no biofilm formation was observed during the first days of experimentation using an initial substrate to microorganisms ratio lower than 0.1. When substrate was added to the reactor as pulses resulting in rapidly changing concentrations, P. putida growth was observed only for substrate to microorganism ratios higher than 0.6, with a maximum Y{sub X/S} of 0.5 g/g. Biofilm development under changing feeding conditions was fast, biomass detachment only being significant for biomass concentrations on the membrane surface that were higher than 16 g/m{sup 2}.

  15. Pseudomonas putida response in membrane bioreactors under salicylic acid-induced stress conditions

    International Nuclear Information System (INIS)

    Collado, Sergio; Rosas, Irene; González, Elena; Gutierrez-Lavin, Antonio; Diaz, Mario

    2014-01-01

    Highlights: • MBR under feed-induced stress conditions: starvation and changing feeding conditions. • High capacity of MBR to withstand high variations in feed loads. • Slow biofilm formation under starvation conditions during the first days. • Observed growth of P. putida for substrate to microorganism ratio higher than 0.6 g/g. • Maximum specific growth rate and growth yield values of around 37.5 h −1 and 0.5 g/g. - Abstract: Starvation and changing feeding conditions are frequently characteristics of wastewater treatment plants. They are typical causes of unsteady-state operation of biological systems and provoke cellular stress. The response of a membrane bioreactor functioning under feed-induced stress conditions is studied here. In order to simplify and considerably amplify the response to stress and to obtain a reference model, a pure culture of Pseudomonas putida was selected instead of an activated sludge and a sole substrate (salicylic acid) was employed. The system degraded salicylic acid at 100–1100 mg/L with a high level of efficiency, showed rapid acclimation without substrate or product inhibition phenomena and good stability in response to unsteady states caused by feed variations. Under starvation conditions, specific degradation rates of around 15 mg/g h were achieved during the adaptation of the biomass to the new conditions and no biofilm formation was observed during the first days of experimentation using an initial substrate to microorganisms ratio lower than 0.1. When substrate was added to the reactor as pulses resulting in rapidly changing concentrations, P. putida growth was observed only for substrate to microorganism ratios higher than 0.6, with a maximum Y X/S of 0.5 g/g. Biofilm development under changing feeding conditions was fast, biomass detachment only being significant for biomass concentrations on the membrane surface that were higher than 16 g/m 2

  16. Echolalic responses by a child with autism to four experimental conditions of sociolinguistic input.

    Science.gov (United States)

    Violette, J; Swisher, L

    1992-02-01

    Studies of the immediate verbal imitations (IVIs) of subjects with echolalia report that features of linguistic or social input alone affect the number of IVIs elicited. This experimental study of a child with echolalia and autism controlled each of these variables while introducing a systematic change in the other. The subject produced more (p less than .05) IVIs in response to unknown lexical words presented with a high degree of directiveness (Condition D) than in response to three other conditions of stimulus presentation (e.g., unknown lexical words, minimally directive style.) Thus, an interaction between the effects of linguistic and social input was demonstrated. IVIs were produced across all conditions, primarily during first presentations of lexical stimuli. Only the IVIs elicited by first presentations of the lexical stimuli during Condition D differed significantly (p less than .05) from the number of IVIs elicited by first presentations of lexical stimuli in other conditions. These findings viewed together suggest that the occurrence of IVIs was related, at least for this child, to an uncertain or informative event and that this response was significantly greater when the lexical stimuli were unknown and presented in a highly directive style.

  17. Physiological and subjective responses in the elderly when using floor heating and air conditioning systems.

    Science.gov (United States)

    Hashiguchi, Nobuko; Tochihara, Yutaka; Ohnaka, Tadakatsu; Tsuchida, Chiaki; Otsuki, Tamio

    2004-11-01

    The purpose of this study was to investigate the effects of a floor heating and air conditioning system on thermal responses of the elderly. Eight elderly men and eight university students sat for 90 minutes in a chair under the following 3 conditions: air conditioning system (A), floor heating system (F) and no heating system (C). The air temperature of sitting head height for condition A was 25 degrees C, and the maximum difference in vertical air temperature was 4 degrees C. The air and floor temperature for condition F were 21 and 29 degrees C, respectively. The air temperature for condition C was 15 degrees C. There were no significant differences in rectal temperature and mean skin temperature between condition A and F. Systolic blood pressure of the elderly men in condition C significantly increased compared to those in condition A and F. No significant differences in systolic blood pressure between condition A and F were found. The percentage of subjects who felt comfortable under condition F was higher than that of those under condition A in both age groups, though the differences between condition F and A was not significant. Relationships between thermal comfort and peripheral (e.g., instep, calf, hand) skin temperature, and the relationship between thermal comfort and leg thermal sensation were significant for both age groups. However, the back and chest skin temperature and back thermal sensation for the elderly, in contrast to that for the young, was not significantly related to thermal comfort. These findings suggested that thermal responses and physiological strain using the floor heating system did not significantly differ from that using the air conditioning system, regardless of the subject age and despite the fact that the air temperature with the floor heating system was lower. An increase in BP for elderly was observed under the condition in which the air temperature was 15 degrees C, and it was suggested that it was necessary for the elderly

  18. Sex differences in learning processes of classical and operant conditioning.

    Science.gov (United States)

    Dalla, Christina; Shors, Tracey J

    2009-05-25

    Males and females learn and remember differently at different times in their lives. These differences occur in most species, from invertebrates to humans. We review here sex differences as they occur in laboratory rodent species. We focus on classical and operant conditioning paradigms, including classical eyeblink conditioning, fear-conditioning, active avoidance and conditioned taste aversion. Sex differences have been reported during acquisition, retention and extinction in most of these paradigms. In general, females perform better than males in the classical eyeblink conditioning, in fear-potentiated startle and in most operant conditioning tasks, such as the active avoidance test. However, in the classical fear-conditioning paradigm, in certain lever-pressing paradigms and in the conditioned taste aversion, males outperform females or are more resistant to extinction. Most sex differences in conditioning are dependent on organizational effects of gonadal hormones during early development of the brain, in addition to modulation by activational effects during puberty and adulthood. Critically, sex differences in performance account for some of the reported effects on learning and these are discussed throughout the review. Because so many mental disorders are more prevalent in one sex than the other, it is important to consider sex differences in learning when applying animal models of learning for these disorders. Finally, we discuss how sex differences in learning continue to alter the brain throughout the lifespan. Thus, sex differences in learning are not only mediated by sex differences in the brain, but also contribute to them.

  19. Effect of different reading interfaces and conditions on the accommodation response

    Directory of Open Access Journals (Sweden)

    Xiao-Feng Wang

    2016-04-01

    Full Text Available AIM:To compare the difference of accommodation response under the variety reading conditions including computer screen, mobile phone screen and printed texts. The investigation also included the accommodation response under these conditions with different distances, brightness, dynamic and static testing status. METHODS:Thirty volunteer subjects were included with normal vision function. The reading target on computer screen, mobile screen and paper were used, respectively. Grand Seiko WAM 5500 infrared automatic refractometer was applied to measure accommodation response. The influence of different reading conditions on accommodation was compared using variance analysis with SPSS17.0.RESULTS:Accommodation lag under the computer screen with high brightness was 0.52±0.24D, that under papers was 0.73±0.28D, that under mobile phone was 0.72±0.29D. Accommodation lag under the computer screen with high brightness was less than that under mobile phones and paper, the differences were statistically significant(PCONCLUSION:Accommodation lag under the computer screen with high brightness is relatively smaller than that under mobile phone or paper. There is no significant difference between those under phones and paper. With the brightness of computers in a certain range, there is no effect for accommodation response.

  20. Application of Whole Genome Expression Analysis to Assess Bacterial Responses to Environmental Conditions

    Science.gov (United States)

    Vukanti, R. V.; Mintz, E. M.; Leff, L. G.

    2005-05-01

    Bacterial responses to environmental signals are multifactorial and are coupled to changes in gene expression. An understanding of bacterial responses to environmental conditions is possible using microarray expression analysis. In this study, the utility of microarrays for examining changes in gene expression in Escherichia coli under different environmental conditions was assessed. RNA was isolated, hybridized to Affymetrix E. coli Genome 2.0 chips and analyzed using Affymetrix GCOS and Genespring software. Major limiting factors were obtaining enough quality RNA (107-108 cells to get 10μg RNA)and accounting for differences in growth rates under different conditions. Stabilization of RNA prior to isolation and taking extreme precautions while handling RNA were crucial. In addition, use of this method in ecological studies is limited by availability and cost of commercial arrays; choice of primers for cDNA synthesis, reproducibility, complexity of results generated and need to validate findings. This method may be more widely applicable with the development of better approaches for RNA recovery from environmental samples and increased number of available strain-specific arrays. Diligent experimental design and verification of results with real-time PCR or northern blots is needed. Overall, there is a great potential for use of this technology to discover mechanisms underlying organisms' responses to environmental conditions.

  1. Dynamics of the near response under natural viewing conditions with an open-view sensor

    Science.gov (United States)

    Chirre, Emmanuel; Prieto, Pedro; Artal, Pablo

    2015-01-01

    We have studied the temporal dynamics of the near response (accommodation, convergence and pupil constriction) in healthy subjects when accommodation was performed under natural binocular and monocular viewing conditions. A binocular open-view multi-sensor based on an invisible infrared Hartmann-Shack sensor was used for non-invasive measurements of both eyes simultaneously in real time at 25Hz. Response times for each process under different conditions were measured. The accommodative responses for binocular vision were faster than for monocular conditions. When one eye was blocked, accommodation and convergence were triggered simultaneously and synchronized, despite the fact that no retinal disparity was available. We found that upon the onset of the near target, the unblocked eye rapidly changes its line of sight to fix it on the stimulus while the blocked eye moves in the same direction, producing the equivalent to a saccade, but then converges to the (blocked) target in synchrony with accommodation. This open-view instrument could be further used for additional experiments with other tasks and conditions. PMID:26504666

  2. Analytical solution for beam with time-dependent boundary conditions versus response spectrum

    International Nuclear Information System (INIS)

    Gou, P.F.; Panahi, K.K.

    2001-01-01

    This paper studies the responses of a uniform simple beam for which the supports are subjected to time-dependent conditions. Analytical solution in terms of series was presented for two cases: (1) Two supports of a simple beam are subjected to a harmonic motion, and (2) One of the two supports is stationary while the other is subjected to a harmonic motion. The results of the analytical solution were investigated and compared with the results of conventional response spectrum method using the beam finite element model. One of the applications of the results presented in this paper can be used to assess the adequacy and accuracy of the engineering approaches such as response spectra methods. It has been found that, when the excitation frequency equals the fundamental frequency of the beam, the results from response spectrum method are in good agreement with the exact calculation. The effects of initial conditions on the responses are also examined. It seems that the non-zero initial velocity has pronounced effects on the displacement time histories but it has no effect on the maximum accelerations. (author)

  3. Spontaneous Recovery After Extinction of the Conditioned Proboscis Extension Response in the Honeybee

    Science.gov (United States)

    Sandoz, Jean-Christophe; Pham-Delègue, Minh-Hà

    2004-01-01

    In honeybees, the proboscis extension response (PER) can be conditioned by associating an odor stimulus (CS) to a sucrose reward (US). Conditioned responses to the CS, which are acquired by most bees after a single CS-US pairing, disappear after repeated unrewarded presentations of the CS, a process called extinction. Extinction is usually thought to be based either on (1) the disruption of the stored CS-US association, or (2) the formation of an inhibitory “CS-no US” association that is better retrieved than the initial CS-US association. The observation of spontaneous recovery, i.e., the reappearance of responses to the CS after time passes following extinction, is traditionally interpreted as a proof for the formation of a transient inhibitory association. To provide a better understanding of extinction in honeybees, we examined whether time intervals during training and extinction or the number of conditioning and extinction trials have an effect on the occurrence of spontaneous recovery. We found that spontaneous recovery mostly occurs when conditioning and testing took place in a massed fashion (1-min intertrial intervals). Moreover, spontaneous recovery depended on the time elapsed since extinction, 1 h being an optimum. Increasing the number of conditioning trials improved the spontaneous recovery level, whereas increasing the number of extinction trials reduced it. Lastly, we show that after single-trial conditioning, spontaneous recovery appears only once after extinction. These elements suggest that in honeybees extinction of the PER actually reflects the impairment of the CS-US association, but that depending on training parameters different memory substrates are affected. PMID:15466313

  4. Response Surface Methodology: An Extensive Potential to Optimize in vivo Photodynamic Therapy Conditions

    International Nuclear Information System (INIS)

    Tirand, Loraine; Bastogne, Thierry; Bechet, Denise M.Sc.; Linder, Michel; Thomas, Noemie; Frochot, Celine; Guillemin, Francois; Barberi-Heyob, Muriel

    2009-01-01

    Purpose: Photodynamic therapy (PDT) is based on the interaction of a photosensitizing (PS) agent, light, and oxygen. Few new PS agents are being developed to the in vivo stage, partly because of the difficulty in finding the right treatment conditions. Response surface methodology, an empirical modeling approach based on data resulting from a set of designed experiments, was suggested as a rational solution with which to select in vivo PDT conditions by using a new peptide-conjugated PS targeting agent, neuropilin-1. Methods and Materials: A Doehlert experimental design was selected to model effects and interactions of the PS dose, fluence, and fluence rate on the growth of U87 human malignant glioma cell xenografts in nude mice, using a fixed drug-light interval. All experimental results were computed by Nemrod-W software and Matlab. Results: Intrinsic diameter growth rate, a tumor growth parameter independent of the initial volume of the tumor, was selected as the response variable and was compared to tumor growth delay and relative tumor volumes. With only 13 experimental conditions tested, an optimal PDT condition was selected (PS agent dose, 2.80 mg/kg; fluence, 120 J/cm 2 ; fluence rate, 85 mW/cm 2 ). Treatment of glioma-bearing mice with the peptide-conjugated PS agent, followed by the optimized PDT condition showed a statistically significant improvement in delaying tumor growth compared with animals who received the PDT with the nonconjugated PS agent. Conclusions: Response surface methodology appears to be a useful experimental approach for rapid testing of different treatment conditions and determination of optimal values of PDT factors for any PS agent.

  5. Boundary condition effect on response modification factor of X-braced steel frames

    Directory of Open Access Journals (Sweden)

    Walid A. Attia

    2018-04-01

    Full Text Available Design of the structures to resist seismic force depends on the theory of dissipation in elastic energy that already exists in response modification factor “R-factor”. The main problem in codes gives a constant value for R-factor, since change in boundary conditions of building change in behavior of braced steel frame structures and that effects on R-factor. This study is an attempt to assess overstrength, ductility and response modification factor of X-braced steel frame under change in boundary conditions, as change in the direction of strong axis of column and connection support type of column besides variation in storey and bays numbers to be 21 frames and each frame has 8 different boundary conditions as sum of 168 cases for analysis. These frames were analyzed by using nonlinear static “pushover” analysis. As results of this study change in support type and direction of strong axis of column give large change in value of R-factor; the minimum value was 4.37 and maximum value 10.97. Minimum value is close to code value that’s mean the code is more conservative in suggesting of R-factor and gives a large factor of safety. Change in the location of bracing gives change in value of R-factor for all boundary conditions. Change in direction of strong axis of columns and support type didn’t give change in value of fundamental period, all boundary conditions. Keywords: Response modification factor, Ductility reduction factor, Overstrength factor, Boundary conditions, Brace frame, Nonlinear static analysis “Pushover”

  6. Jatropha curcasand Ricinus communisdisplay contrasting photosynthetic mechanisms in response to environmental conditions

    Directory of Open Access Journals (Sweden)

    Milton Costa Lima Neto

    2015-06-01

    Full Text Available Higher plants display different adaptive strategies in photosynthesis to cope with abiotic stress. In this study, photosynthetic mechanisms and water relationships displayed byJatropha curcasL. (physic nuts andRicinus communisL. (castor bean, in response to variations in environmental conditions, were assessed.R. communis showed higher CO2 assimilation, stomatal and mesophyll conductance thanJ. curcas as light intensity and intercellular CO2 pressure increased. On the other hand,R. communis was less effective in stomatal control in response to adverse environmental factors such as high temperature, water deficit and vapor pressure deficit, indicating lower water use efficiency. Conversely,J. curcas exhibited higher photosynthetic efficiency (gas exchange and photochemistry and water use efficiency under these adverse environmental conditions.R. communisdisplayed higher potential photosynthesis, but exhibited a lowerin vivo Rubisco carboxylation rate (Vcmax and maximum electron transport rate (Jmax. During the course of a typical day, in a semiarid environment, with high irradiation, high temperature and high vapor pressure deficit, but exposed to well-watered conditions, the two studied species presented similar photosynthesis. Losing potential photosynthesis, but maintaining favorable water status and increasing non-photochemical quenching to avoid photoinhibition, are important acclimation mechanisms developed byJ. curcas to cope with dry and hot conditions. We suggest thatJ. curcas is more tolerant to hot and dry environments thanR. communis but the latter species displays higher photosynthetic efficiency under well-watered and non-stressful conditions.

  7. Probabilistic assessment of Juragua Nuclear Power Plant response under station blackout conditions

    International Nuclear Information System (INIS)

    Valhuerdi, C.; Vilaragut, J.J.; Perdomo, M.; Torres, A.

    1995-01-01

    The preliminary results concerning the response of station blackout are shown in this paper. These results have been obtained in the framework of initiator lass of external electrical supply as a aport of the revision o of the current probabilistic safety analysis. The work is also based on the results reported in the thermohydraulic calculations of VVER 440 plants responses under these conditions and the experience of this type of notified incidents. Finally, a comparative analysis with the results obtained for other reactor technologies is presented

  8. Differential effect of conditioning regimens on cytokine responses during allogeneic stem cell transplantation

    DEFF Research Database (Denmark)

    Andersen, J; Heilmann, C; Jacobsen, N

    2006-01-01

    The purpose of this study was to characterize cytokine responses during conditioning in patients undergoing allogeneic stem cell transplantation (SCT) with the aim to identify which markers that may reliably reflect inflammatory activity during conditioning. We investigated inflammatory and anti.......002), followed by VP-16 (184%, P=0.03), cyclophosphamide (129%, P=0.03) and total body irradiation (148%, P=0.0005). Administration of i.v. busulfan (Busilvex; BU) was not associated with significant changes in sTNFRI levels. At day 0 (the day of stem cell infusion) the sTNFRI levels were not only elevated...

  9. Why trace and delay conditioning are sometimes (but not always) hippocampal dependent: A computational model

    Science.gov (United States)

    Moustafa, Ahmed A.; Wufong, Ella; Servatius, Richard J.; Pang, Kevin C. H.; Gluck, Mark A.; Myers, Catherine E.

    2013-01-01

    A recurrent-network model provides a unified account of the hippocampal region in mediating the representation of temporal information in classical eyeblink conditioning. Much empirical research is consistent with a general conclusion that delay conditioning (in which the conditioned stimulus CS and unconditioned stimulus US overlap and co-terminate) is independent of the hippocampal system, while trace conditioning (in which the CS terminates before US onset) depends on the hippocampus. However, recent studies show that, under some circumstances, delay conditioning can be hippocampal-dependent and trace conditioning can be spared following hippocampal lesion. Here, we present an extension of our prior trial-level models of hippocampal function and stimulus representation that can explain these findings within a unified framework. Specifically, the current model includes adaptive recurrent collateral connections that aid in the representation of intra-trial temporal information. With this model, as in our prior models, we argue that the hippocampus is not specialized for conditioned response timing, but rather is a general-purpose system that learns to predict the next state of all stimuli given the current state of variables encoded by activity in recurrent collaterals. As such, the model correctly predicts that hippocampal involvement in classical conditioning should be critical not only when there is an intervening trace interval, but also when there is a long delay between CS onset and US onset. Our model simulates empirical data from many variants of classical conditioning, including delay and trace paradigms in which the length of the CS, the inter-stimulus interval, or the trace interval is varied. Finally, we discuss model limitations, future directions, and several novel empirical predictions of this temporal processing model of hippocampal function and learning. PMID:23178699

  10. Flight activity and responses to climatic conditions of two subspecies of Melipona marginata Lepeletier (Apidae, Meliponinae)

    Energy Technology Data Exchange (ETDEWEB)

    Kleinert-Giovannini, A; Imperatriz-Fonseca, V L

    1986-01-01

    The flight activity of two colonies of M. m. marginata and six colonies of M. m. obscurior was studied in Sao Paulo, Brazil during three periods in 1981-1983. All colonies were hived except for one colony of M. m. obscurior which nested in a hollow tree. The two subspecies showed the same responses to the climatic factors analyzed. Flight activity was correlated positively with temperature and negatively with RH. In favorable conditions foraging took place throughout the day but both species were most active between 11 and 13 h. In the last observation period (October 1982-January 1983), when only two obscurior colonies were studied, flight activity was not correlated to RH, occurring even when RH was unfavorably high. This was a very rainy season, and it is suggested that the behavior of the bees indicates a flexible response to prevailing weather conditions.

  11. Screening for Osmotic Stress Responses in Rice Varieties under Drought Condition

    OpenAIRE

    Simon Swapna; Korukkanvilakath Samban Shylaraj

    2017-01-01

    Drought is the major abiotic stress factor that limits rice production worldwide. To evaluate the osmotic stress responses in rice varieties under drought condition, a total of 42 high-yielding rice varieties were collected from various research stations of Kerala Agricultural University in India. The experimental setup comprises of initial hydroponic treatments at different osmotic potentials, artificially induced by desired strengths of polyethylene glycol (PEG6000), and followed by the pot...

  12. The Development of Forms of Corporate Social Responsibility in Russia in the Current Economic Conditions

    Directory of Open Access Journals (Sweden)

    Natalya Arzumanova

    2015-02-01

    Full Text Available The article reveals the characteristic features of modern trends in the formation and implementation of corporate social responsibility in Russia in the current economic conditions, which is based on the fact that reasonable economic interests oriented business not only on maximizing profits, but also to improve their own macro - socio-economic, natural, political, through voluntary investment profits in the respective areas.

  13. Parallel Study of HEND, RAD, and DAN Instrument Response to Martian Radiation and Surface Conditions

    Science.gov (United States)

    Martiniez Sierra, Luz Maria; Jun, Insoo; Litvak, Maxim; Sanin, Anton; Mitrofanov, Igor; Zeitlin, Cary

    2015-01-01

    Nuclear detection methods are being used to understand the radiation environment at Mars. JPL (Jet Propulsion Laboratory) assets on Mars include: Orbiter -2001 Mars Odyssey [High Energy Neutron Detector (HEND)]; Mars Science Laboratory Rover -Curiosity [(Radiation Assessment Detector (RAD); Dynamic Albedo Neutron (DAN))]. Spacecraft have instruments able to detect ionizing and non-ionizing radiation. Instrument response on orbit and on the surface of Mars to space weather and local conditions [is discussed] - Data available at NASA-PDS (Planetary Data System).

  14. Broad-Scale Environmental Conditions Responsible for Post-Fire Vegetation Dynamics

    OpenAIRE

    Casady, Grant M.; Marsh, Stuart E.

    2010-01-01

    Ecosystem response to disturbance is influenced by environmental conditions at a number of scales. Changes in climate have altered fire regimes across the western United States, and have also likely altered spatio-temporal patterns of post-fire vegetation regeneration. Fire occurrence data and a vegetation index (NDVI) derived from the NOAA Advanced Very High Resolution Radiometer (AVHRR) were used to monitor post-fire vegetation from 1989 to 2007. We first investigated differences in post-fi...

  15. Elite Athletes’ In-event Competitive Anxiety Responses and Psychological Skills Usage under Differing Conditions

    Science.gov (United States)

    Hagan, John E.; Pollmann, Dietmar; Schack, Thomas

    2017-01-01

    Background and Purpose: Even though the assessment of competitive anxiety responses (intensity, interpretation, and frequency) using the time-to-event paradigm has gained much attention, literature on the account of these same experiences in-event and their corresponding psychological skills adopted under differing conditions is limited. This is a follow up investigation to establish the extent to which associated anxiety responses are stable or dynamic and whether this pattern could be related to reported psychological skills under low or high stressful conditions across gender. Methods: Twenty-three high level (N = 13 males and 10 females) Ghanaian Table Tennis players provided data through completion of modified versions of Competitive State Anxiety Inventory-2, incorporated with directional and frequency of intrusion scales and the Test of Performance Strategies inventory during breaks within competitive fixtures. Results: MANCOVAs (gender × stress condition) with follow-up analyses revealed no significant interactions and no main effect for gender but significant main effects were realized for all anxiety dimensions and psychological skills for only the second factor. Specifically, the intensity and frequency of cognitive and somatic state anxiety symptoms increased and were interpreted as debilitative under the high stress condition, although self-confidence and other array of psychological skills were highly displayed under the same stressful condition. Conclusion: Findings highlight the dynamic characteristics of in-event associated anxiety responses and ineffectiveness of deployed psychological skills regardless of gender. These perhaps show the exceptionality of affective experiences in an African setting, suggesting a culturally diversified approach to psychological skills application, if desirable effects are to be attained. PMID:29312103

  16. Influence of rearing conditions on voluntary ethanol intake and response to stress in rats.

    Science.gov (United States)

    Rockman, G E; Hall, A M; Markert, L E; Glavin, G B

    1988-03-01

    The effects of exposure to four environmental rearing conditions on subsequent voluntary ethanol intake and response to immobilization stress were examined. Male weanling rats were reared in an enriched environment, with a female partner, with a male partner, or individually, for 90 days. At 111 days of age, voluntary consumption of ethanol in increasing concentrations (3 to 9%, v/v) was assessed. Following the ethanol-exposure period, rats were randomly divided into stressed and nonstressed groups and exposed to 3 h of immobilization. Results indicated that the enriched animals consumed greater amounts of ethanol as compared to all other groups, suggesting that the enriched environment and not handling, housing conditions, or the presence of another male or female is responsible for the observed increase in ethanol drinking behavior. Ulcer data indicated that among environmentally enriched rats, ethanol attenuated stress ulcer development relative to their non-ethanol-exposed but stressed controls. In nonstressed enriched rats, ethanol alone exacerbated stomach damage. We suggest that environmental rearing conditions markedly influence the complex interaction between ethanol intake and the response to stress.

  17. Olfactory aversive conditioning alters olfactory bulb mitral/tufted cell glomerular odor responses

    Directory of Open Access Journals (Sweden)

    Max L Fletcher

    2012-03-01

    Full Text Available The anatomical organization of receptor neuron input into the olfactory bulb (OB allows odor information to be transformed into an odorant-specific spatial map of mitral/tufted cell glomerular activity at the upper level of the olfactory bulb. In other sensory systems, neuronal representations of stimuli can be reorganized or enhanced following learning. While the mammalian OB has been shown to undergo experience-dependent plasticity at the glomerular level, it is still unclear if similar representational change occurs within mitral/tufted cell glomerular odor representations following learning. To address this, odorant-evoked glomerular activity patterns were imaged in mice expressing a GFP-based calcium indicator (GCaMP2 in OB mitral/tufted cells. Glomerular odor responses were imaged before and after olfactory associative conditioning to aversive foot shock. Following conditioning, we found no overall reorganization of the glomerular representation. Training, however, did significantly alter the amplitudes of individual glomeruli within the representation in mice in which the odor was presented together with foot shock. Further, the specific pairing of foot shock with odor presentations lead to increased responses primarily in initially weakly activated glomeruli. Overall, these results suggest that associative conditioning can enhance the initial representation of odors within the olfactory bulb by enhancing responses to the learned odor in some glomeruli.

  18. [CO2 response process and its simulation of Prunus sibirica photosynthesis under different soil moisture conditions].

    Science.gov (United States)

    Wu, Qin; Zhang, Guang-Can; Pei, Bin; Xu, Zhi-Qiang; Zhao, Yu; Fang, Li-Dong

    2013-06-01

    Taking the two-year old potted Prunus sibirica seedlings as test materials, and using CIRAS-2 photosynthetic system, this paper studied the CO2 response process of P. sibirica photosynthesis in semi-arid loess hilly region under eight soil moisture conditions. The CO2 response data of P. sibirica were fitted and analyzed by rectangular hyperbola model, exponential equation, and modified rectangular hyperbola model. Meanwhile, the quantitative relationships between the photosynthesis and the soil moisture were discussed. The results showed that the CO2 response process of P. sibirica photosynthesis had obvious response characteristics to the soil moisture threshold. The relative soil water content (RWC) required to maintain the higher photosynthetic rate (P(n)) and carboxylation efficiency (CE) of P. sibirica was in the range of 46.3%-81.9%. In this RWC range, the photosynthesis did not appear obvious CO2 saturated inhibition phenomenon. When the RWC exceeded this range, the photosynthetic capacity (P(n max)), CE, and CO2 saturation point (CSP) decreased evidently. Under different soil moisture conditions, there existed obvious differences among the three models in simulating the CO2 response data of P. sibirica. When the RWC was in the range of 46.3%-81.9%, the CO2 response process and the characteristic parameters such as CE, CO2 compensation point (see symbol), and photorespiration rate (R(p)) could be well fitted by the three models, and the accuracy was in the order of modified rectangular hyperbola model > exponential equation > rectangular hyperbola model. When the RWC was too high or too low, namely, the RWC was > 81.9% or CO2 response process and the characteristic parameters. It was suggested that when the RWC was from 46.3% to 81.9%, the photosynthetic efficiency of P. sibirica was higher, and, as compared with rectangular hyperbola model and exponential equation, modified rectangular hyperbola model had more applicability to fit the CO2 response data of

  19. OPTIMIZATION OF PRETREATMENT CONDITIONS OF CARROTS TO MAXIMIZE JUICE RECOVERY BY RESPONSE SURFACE METHODOLOGY

    Directory of Open Access Journals (Sweden)

    H. K. SHARMA

    2006-12-01

    Full Text Available Carrot juice was expressed in a hydraulic press using a wooden set up. Carrot samples pretreated at different designed combinations, using Central Composite Rotatable Design (CCRD, Response Surface Methodology (RSM, of pH, temperature and time were expressed and juice so obtained was characterized for various physico-chemical parameters which involved yield, TSS and water content, reducing sugars, total sugars and color (absorbance. The study indicated that carrots exposed to the different pretreatment conditions resulted in increased amount of yield than that of the control. The responses were optimized by numerical method and were found to be 78.23% yield, 0.93% color (abs, 3.41% reducing sugars, 5.53% total sugars, 6.69obrix, and 90.50% water content. All the derived mathematical models for the various responses were found to be fit significantly to predict the data.

  20. Response Load Extrapolation for Wind Turbines during Operation Based on Average Conditional Exceedance Rates

    DEFF Research Database (Denmark)

    Toft, Henrik Stensgaard; Naess, Arvid; Saha, Nilanjan

    2011-01-01

    to cases where the Gumbel distribution is the appropriate asymptotic extreme value distribution. However, two extra parameters are introduced by which a more general and flexible class of extreme value distributions is obtained with the Gumbel distribution as a subclass. The general method is implemented...... within a hierarchical model where the variables that influence the loading are divided into ergodic variables and time-invariant non-ergodic variables. The presented method for statistical response load extrapolation was compared with the existing methods based on peak extrapolation for the blade out......The paper explores a recently developed method for statistical response load (load effect) extrapolation for application to extreme response of wind turbines during operation. The extrapolation method is based on average conditional exceedance rates and is in the present implementation restricted...

  1. Transcriptional Response of Desulfovibrio vulgaris Hildenborough to Oxidative Stress Mimicking Environmental Conditions

    Energy Technology Data Exchange (ETDEWEB)

    Pereira, Patricia M.; He, Qiang; Xavier, Antonio V.; Zhou, Jizhong; Pereira, Ines A.C.; Louro, Ricardo O.

    2008-03-12

    Sulphate-reducing bacteria are anaerobes readily found in oxic-anoxic interfaces. Multiple defence pathways against oxidative conditions were identified in these organisms and proposed to be differentially expressed under different concentrations of oxygen, contributing to their ability to survive oxic conditions. In this study, Desulfovibrio vulgaris Hildenborough cells were exposed to the highest concentration of oxygen that sulphate-reducing bacteria are likely to encounter in natural habitats, and the global transcriptomic response was determined. 307 genes were responsive, with cellular roles in energy metabolism, protein fate, cell envelope and regulatory functions, including multiple genes encoding heat shock proteins, peptidases and proteins with heat shock promoters. Of the oxygen reducing mechanisms of D. vulgaris only the periplasmic hydrogen-dependent mechanism is up-regulated, involving the [NiFeSe]hydrogenase, formate dehydrogenase(s) and the Hmc membrane complex. The oxidative defence response concentrates on damage repair by metal-free enzymes. These data, together with the down regulation of the Fur operon, which restricts the availability of iron, and the lack of response of the PerR operon, suggest that a major effect of this oxygen stress is the inactivation and/or degradation of multiple metalloproteins present in D. vulgaris as a consequence of oxidative damage to their metal clusters.

  2. Stomata character and chlorophyll content of tomato in response to Zn application under drought condition

    Science.gov (United States)

    Sakya, A. T.; Sulistyaningsih, E.; Indradewa, D.; Purwanto, B. H.

    2018-03-01

    This experiment was performed in order to evaluate the effects of Zn application under drought condition on tomato, especially its chlorophyll content and stomata character. This experiment was arranged in factorial using randomized complete block design with three replications. The treatment consisted of the Zn application method, namely: soil and foliar, the Zn dosage, namely: 0, 40 and 60 mg ZnSO4 kg-1 soil and two cultivars of tomato, namely: ‘Tyrana’ F1 and ‘Permata’ F1. The stress condition was induced by watering every 12 days of 3 weeks after transplanting until harvesting. The results showed that the soil with a Zn application under drought conditions increased the aperture stomata, chlorophyll b and chlorophyll a/b ratio. The response of stomata character, chlorophyll a and total chlorophyll in both cultivars was similar.

  3. Temperate heath plant response to dry conditions depends on growth strategy and less on physiology

    DEFF Research Database (Denmark)

    Albert, Kristian Rost; Kongstad, J.; Schmidt, I. K.

    2012-01-01

    of these differences in response in dry versus rewetting conditions can be used to highlight the limitations coherent in different strategies adopted by, for example, evergreen shrubs and grasses. We investigated the leaf-level photosynthetic performance, leaf C, N and d13C along with vegetation cover and biomass...... in the evergreen dwarf shrub Calluna vulgaris and the grass species Deschampsia flexuosa in a temperate heath during seasonal changes in soil moisture. Higher photosynthetic capacity compensated for lower stomatal conductance and sustained higher rates of photosynthesis in the grass compared to the dwarf shrub....... In combination with dieback of aboveground biomass and reduction of stomatal conductance reduction during dry conditions, the grass continued to have high carbon uptake in the remaining leaves. The dwarf shrub endured the dry conditions by preserving shoot biomass and reducing stomatal conductance. Soil...

  4. Probabilistic assessment of the Juragua NPP response under Station Blackout conditions

    International Nuclear Information System (INIS)

    Valhuerdi Debesa, C.; Vilaragut Llanes, J.J.

    1996-01-01

    Assessment of the NPP response under SBO (station Blackout) conditions is a current safety issue of special interest, In the case of Juragua NPP, the safety assessment related to this topic is very important, taking into account the peculiarities of the Cuban Electro energetic System: small and long island, without possibilities of conexion beyond its borders and under the incidence of tropical phenomena In this papers a preliminary evaluation is presented of the potential incidence of Station Blackout conditions for Juragua NPP. the importance of this sort of events for the safety of the plant is evaluated, the factors which condition it are identified and measures for its prevention or recovering the normal situation if such an event takes place are proposed

  5. Fern Stomatal Responses to ABA and CO2 Depend on Species and Growth Conditions.

    Science.gov (United States)

    Hõrak, Hanna; Kollist, Hannes; Merilo, Ebe

    2017-06-01

    Changing atmospheric CO 2 levels, climate, and air humidity affect plant gas exchange that is controlled by stomata, small pores on plant leaves and stems formed by guard cells. Evolution has shaped the morphology and regulatory mechanisms governing stomatal movements to correspond to the needs of various land plant groups over the past 400 million years. Stomata close in response to the plant hormone abscisic acid (ABA), elevated CO 2 concentration, and reduced air humidity. Whether the active regulatory mechanisms that control stomatal closure in response to these stimuli are present already in mosses, the oldest plant group with stomata, or were acquired more recently in angiosperms remains controversial. It has been suggested that the stomata of the basal vascular plants, such as ferns and lycophytes, close solely hydropassively. On the other hand, active stomatal closure in response to ABA and CO 2 was found in several moss, lycophyte, and fern species. Here, we show that the stomata of two temperate fern species respond to ABA and CO 2 and that an active mechanism of stomatal regulation in response to reduced air humidity is present in some ferns. Importantly, fern stomatal responses depend on growth conditions. The data indicate that the stomatal behavior of ferns is more complex than anticipated before, and active stomatal regulation is present in some ferns and has possibly been lost in others. Further analysis that takes into account fern species, life history, evolutionary age, and growth conditions is required to gain insight into the evolution of land plant stomatal responses. © 2017 American Society of Plant Biologists. All Rights Reserved.

  6. Differences in finger skin contact cooling response between an arterial occlusion and a vasodilated condition.

    Science.gov (United States)

    Jay, Ollie; Havenith, George

    2006-05-01

    To assess the presence and magnitude of the effect of skin blood flow on finger skin cooling on contact with cold objects against the background of circulatory disorder risks in occupational exposures, this study investigates the effect of zero vs. close-to-maximal hand blood flow on short-term (cooling response at a contact pressure that allows capillary perfusion of the distal pulp of the fingertip. Six male volunteers touched a block of aluminium with a finger contact force of 0.5 N at a temperature of -2 degrees C under a vasodilated and an occluded condition. Before both conditions, participants were required to exercise in a hot room for > or = 30 min for cutaneous vasodilation to occur (increase in rectal temperature of 1 degrees C). Under the vasodilated condition, forearm blood flow rate rose as high as 16.8 ml.100 ml(-1).min(-1). Under the occluded condition, the arm was exsanguinated, after which a blood pressure cuff was secured on the wrist inducing arterial occlusion. Contact temperature of the finger pad during the subsequent cold contact exposure was measured. No significant difference was found between the starting skin temperatures for the two blood flow conditions, but a distinct difference in shape of the contact cooling curve was apparent between the two blood flow conditions, with Newtonian cooling observed under the occluded condition, whereas a rewarming of the finger skin toward the end of the exposure occurred for the vasodilated condition. Blood flow was found to significantly increase contact temperature from 40 s onward (P cooling during a vasodilated state.

  7. Electric signalling in fruit trees in response to water applications and light-darkness conditions.

    Science.gov (United States)

    Gurovich, Luis A; Hermosilla, Paulo

    2009-02-15

    A fundamental property of all living organisms is the generation and conduction of electrochemical impulses throughout their different tissues and organs, resulting from abiotic and biotic changes in environmental conditions. In plants and animals, signal transmission can occur over long and short distances, and it can correspond to intra- and inter-cellular communication mechanisms that determine the physiological behaviour of the organism. Rapid plant and animal responses to environmental changes are associated with electrical excitability and signalling. The same molecules and pathways are used to drive physiological responses, which are characterized by movement (physical displacement) in animals and by continuous growth in plants. In the field of environmental plant electrophysiology, automatic and continuous measurements of electrical potential differences (DeltaEP) between plant tissues can be effectively used to study information transport mechanisms and physiological responses that result from external stimuli on plants. A critical mass of data on electrical behaviour in higher plants has accumulated in the last 5 years, establishing plant neurobiology as the most recent discipline of plant science. In this work, electrical potential differences were monitored continuously using Ag/AgCl microelectrodes, which were inserted 15mm deep into sapwood at various positions in the trunks of several fruit-bearing trees. Electrodes were referenced to an unpolarisable Ag/AgCl microelectrode, which was installed 5cm deep in the soil. Systematic patterns of DeltaEP during day-night cycles and at different conditions of soil water availability are discussed as alternative tools to assess early plant stress conditions. This research relates to the adaptive response of trees to soil water availability and light-darkness cycles.

  8. Pore-scale investigation on the response of heterotrophic respiration to moisture conditions in heterogeneous soils

    Energy Technology Data Exchange (ETDEWEB)

    Yan, Zhifeng; Liu, Chongxuan; Todd-Brown, Katherine E.; Liu, Yuanyuan; Bond-Lamberty, Ben; Bailey, Vanessa L.

    2016-11-15

    The relationship between microbial respiration rate and soil moisture content is an important property for understanding and predicting soil organic carbon degradation, CO2 production and emission, and their subsequent effects on climate change. This paper reports a pore-scale modeling study to investigate the response of heterotrophic respiration to moisture conditions in soils and to evaluate various factors that affect this response. X-ray computed tomography was used to derive soil pore structures, which were then used for pore-scale model investigation. The pore-scale results were then averaged to calculate the effective respiration rates as a function of water content in soils. The calculated effective respiration rate first increases and then decreases with increasing soil water content, showing a maximum respiration rate at water saturation degree of 0.75 that is consistent with field and laboratory observations. The relationship between the respiration rate and moisture content is affected by various factors, including pore-scale organic carbon bioavailability, the rate of oxygen delivery, soil pore structure and physical heterogeneity, soil clay content, and microbial drought resistivity. Simulations also illustrates that a larger fraction of CO2 produced from microbial respiration can be accumulated inside soil cores under higher saturation conditions, implying that CO2 flux measured on the top of soil cores may underestimate or overestimate true soil respiration rates under dynamic moisture conditions. Overall, this study provides mechanistic insights into the soil respiration response to the change in moisture conditions, and reveals a complex relationship between heterotrophic microbial respiration rate and moisture content in soils that is affected by various hydrological, geochemical, and biophysical factors.

  9. Multivariate prediction of spontaneous repetitive responses in ventricular myocardium exposed in vitro to simulated ischemic conditions.

    Science.gov (United States)

    Schiariti, M; Puddu, P E; Rouet, R

    1994-06-01

    Guinea-pig ventricular myocardium was partly exposed to normal Tyrode's superfusion and partly to altered conditions (using modified Tyrode's solution) set to simulate acute myocardial ischemia (PO2 80 +/- 10 mmHg; no glucose; pH 7.00 +/- 0.05; K+ 12 mM). Using a double-chamber tissue bath and standard microelectrode technique, the occurrence of spontaneous repetitive responses was investigated during simulated ischemia (occlusion) and after reperfusing the previously ischemic superfused tissue with normal Tyrode's solution (reperfusion). In 62 experiments (42 animals) the effects of: (1) duration of simulated ischemia (1321 +/- 435 s), (2) stimulation rate (1002 +/- 549 ms) and (3) number of successive simulated ischemic periods (occlusions) (1.58 +/- 0.92) on: (1) resting membrane potential, (2) action potential amplitude, (3) duration of 50 and 90% action potentials and (4) maximal upstroke velocity of action potential were studied. All variables were considered as gradients (delta) between normal and ischemic tissue. Both during occlusion and upon reperfusion, spontaneous repetitive responses were coded as single, couplets, salvos (three to nine and > 10) or total spontaneous repetitive responses (coded present when at least one of the above-mentioned types was seen). The incidence of total spontaneous repetitive responses was 31% (19/62) on occlusion and 85% (53/62) upon reperfusion. Cox's models (forced and stepwise) were used to predict multivariately the occurrence of arrhythmic events considered as both total spontaneous repetitive responses and as separate entities. These models were applicable since continuous monitoring of the experiments enabled exact timing of spontaneous repetitive response onset during both occlusion and reperfusion. In predicting reperfusion spontaneous repetitive responses, total spontaneous repetitive responses and blocks observed during the occlusion period were also considered. Total occlusion spontaneous repetitive responses

  10. Responsiveness of five condition-specific and generic outcome assessment instruments for chronic pain

    Directory of Open Access Journals (Sweden)

    Verra Martin L

    2008-04-01

    Full Text Available Abstract Background Changes of health and quality-of-life in chronic conditions are mostly small and require specific and sensitive instruments. The aim of this study was to determine and compare responsiveness, i.e. the sensitivity to change of five outcome instruments for effect measurement in chronic pain. Methods In a prospective cohort study, 273 chronic pain patients were assessed on the Numeric Rating Scale (NRS for pain, the Short Form 36 (SF-36, the Multidimensional Pain Inventory (MPI, the Hospital Anxiety and Depression Scale (HADS, and the Coping Strategies Questionnaire (CSQ. Responsiveness was quantified by effect size (ES and standardized response mean (SRM before and after a four week in-patient interdisciplinary pain program and compared by the modified Jacknife test. Results The MPI measured pain more responsively than the SF-36 (ES: 0.85 vs 0.72, p = 0.053; SRM: 0.72 vs 0.60, p = 0.027 and the pain NRS (ES: 0.85 vs 0.62, p Conclusion The MPI was most responsive in all comparable domains followed by the SF-36. The pain-specific MPI and the generic SF-36 can be recommended for comprehensive and specific bio-psycho-social effect measurement of health and quality-of-life in chronic pain.

  11. Determination of Optimum Condition of Leucine Content in Beef Protein Hydrolysate using Response Surface Methodology

    International Nuclear Information System (INIS)

    Siti Roha Ab Mutalib; Zainal Samicho; Noriham Abdullah

    2016-01-01

    The aim of this study is to determine the optimum condition of leucine content in beef hydrolysate. Beef hydrolysate was prepared by enzymatic hydrolysis using bromelain enzyme produced from pineapple peel. Parameter conditions such as concentration of bromelain, hydrolysis temperature and hydrolysis time were assessed to obtain the optimum leucine content of beef hydrolysate according to experimental design which was recommended by response surface methodology (RSM). Leucine content in beef hydrolysate was determined using AccQ. Tag amino acid analysis method using high performance liquid chromatography (HPLC). The condition of optimum leucine content was at bromelain concentration of 1.38 %, hydrolysis temperature of 42.5 degree Celcius and hydrolysis time of 31.59 hours with the predicted leucine content of 26.57 %. The optimum condition was verified with the leucine value obtained was 26.25 %. Since there was no significant difference (p>0.05) between the predicted and verified leucine values, thus it indicates that the predicted optimum condition by RSM can be accepted to predict the optimum leucine content in beef hydrolysate. (author)

  12. Cellular Responses of the Lichen Circinaria gyrosa in Mars-Like Conditions

    Directory of Open Access Journals (Sweden)

    Rosa de la Torre Noetzel

    2018-03-01

    differences could be detected and used as markers of the UV-induced damage to the lichen membranes. Based on its viability responses after rehydration, our study shows that the test lichen survived the 30-day incubation in the Mars chamber particularly under niche conditions. However, the photobiont was not able to photosynthesize under the Mars-like conditions, which indicates that the surface of Mars is not a habitable place for C. gyrosa.

  13. Cellular Responses of the Lichen Circinaria gyrosa in Mars-Like Conditions.

    Science.gov (United States)

    de la Torre Noetzel, Rosa; Miller, Ana Z; de la Rosa, José M; Pacelli, Claudia; Onofri, Silvano; García Sancho, Leopoldo; Cubero, Beatriz; Lorek, Andreas; Wolter, David; de Vera, Jean P

    2018-01-01

    detected and used as markers of the UV-induced damage to the lichen membranes. Based on its viability responses after rehydration, our study shows that the test lichen survived the 30-day incubation in the Mars chamber particularly under niche conditions. However, the photobiont was not able to photosynthesize under the Mars-like conditions, which indicates that the surface of Mars is not a habitable place for C . gyrosa .

  14. The influence of cycling intensity upon cognitive response during inferred practice and competition conditions.

    Science.gov (United States)

    Duncan, Michael J; Clarke, Neil D; Cox, Martin; Smith, Mike

    2017-10-01

    In many sport and exercise situations, cognitive performance is required under conditions of high physiological load and high cognitive anxiety. However, few studies have assessed all these components in situ. The current study sought to address this issue. Fourteen adults (9 males, 5 females) completed 2 incremental exercise trials (perceived competition or perceived practice) in a counterbalanced order. Cognitive performance, via a test of visual discrimination, rating of perceived exertion (RPE), heart rate (HR), blood lactate (Bla), and anxiety scores, was recorded at rest, 70% [Formula: see text] and 90% [Formula: see text]. Visual discrimination response times were faster at rest compared to 70% (P = 0.001) and 90% [Formula: see text] (P = 0.002) and at 70% compared to 90% [Formula: see text] (P = 0.04) in the competitive condition. HR post-instructions (P = 0.0001), at 70% (P = 0.001) and 90% [Formula: see text] (P = 0.0001), was significantly higher in competition compared to practice. RPE was higher in the competitive condition compared to the practice condition (P = 0.023). Cognitive anxiety intensity was significantly higher in the competitive condition, at 70% and 90% [Formula: see text] (P = 0.001). This study suggests that cognitive performance is more negatively affected when physiological arousal and cognitive anxiety are at their highest. Coaches and athletes should be mindful of such effects and seek to develop skills to offset such responses or to structure training to better represent competition.

  15. Exposures to Conditioned Flavours with Different Hedonic Values Induce Contrasted Behavioural and Brain Responses in Pigs

    Science.gov (United States)

    Clouard, Caroline; Jouhanneau, Mélanie; Meunier-Salaün, Marie-Christine; Malbert, Charles-Henri; Val-Laillet, David

    2012-01-01

    This study investigated the behavioural and brain responses towards conditioned flavours with different hedonic values in juvenile pigs. Twelve 30-kg pigs were given four three-day conditioning sessions: they received three different flavoured meals paired with intraduodenal (i.d.) infusions of 15% glucose (FGlu), lithium chloride (FLiCl), or saline (control treatment, FNaCl). One and five weeks later, the animals were subjected to three two-choice feeding tests without reinforcement to check the acquisition of a conditioned flavour preference or aversion. In between, the anaesthetised pigs were subjected to three 18FDG PET brain imaging coupled with an olfactogustatory stimulation with the conditioned flavours. During conditioning, the pigs spent more time lying inactive, and investigated their environment less after the FLiCl than the FNaCl or FGlu meals. During the two-choice tests performed one and five weeks later, the FNaCl and FGlu foods were significantly preferred over the FLICl food even in the absence of i.d. infusions. Surprisingly, the FNaCl food was also preferred over the FGlu food during the first test only, suggesting that, while LiCl i.d. infusions led to a strong flavour aversion, glucose infusions failed to induce flavour preference. As for brain imaging results, exposure to aversive or less preferred flavours triggered global deactivation of the prefrontal cortex, specific activation of the posterior cingulate cortex, as well as asymmetric brain responses in the basal nuclei and the temporal gyrus. In conclusion, postingestive visceral stimuli can modulate the flavour/food hedonism and further feeding choices. Exposure to flavours with different hedonic values induced metabolism differences in neural circuits known to be involved in humans in the characterization of food palatability, feeding motivation, reward expectation, and more generally in the regulation of food intake. PMID:22685528

  16. Optimization of deposition conditions of CdS thin films using response surface methodology

    Energy Technology Data Exchange (ETDEWEB)

    Yücel, Ersin, E-mail: dr.ersinyucel@gmail.com [Department of Physics, Faculty of Arts and Sciences, Mustafa Kemal University, 31034 Hatay (Turkey); Güler, Nuray [Department of Physics, Faculty of Arts and Sciences, Mustafa Kemal University, 31034 Hatay (Turkey); Yücel, Yasin [Department of Chemistry, Faculty of Arts and Sciences, Mustafa Kemal University, 31034 Hatay (Turkey)

    2014-03-15

    Highlights: • Statistical methods used for optimization of CdS deposition parameters. • The morphology of the films was smooth, homogeneous and continuous. • Optimal conditions found as pH 11, stirring speed:361 rpm and deposition time: 55 min. • CdS thin film band gap value was 2.72 eV under the optimum conditions. -- Abstract: Cadmium sulfide (CdS) thin films were prepared on glass substrates by chemical bath deposition (CBD) technique under different pH, stirring speed and deposition time. Response Surface Methodology (RSM) and Central Composite Design (CCD) were used to optimization of deposition parameters of the CdS thin films. RSM and CCD were also used to understand the significance and interaction of the factors affecting the film quality. Variables were determined as pH, stirring speed and deposition time. The band gap was chosen as response in the study. Influences of the variables on the band gap and the film quality were investigated. 5-level-3-factor central composite design was employed to evaluate the effects of the deposition conditions parameters such as pH (10.2–11.8), stirring speed (132–468 rpm) and deposition time (33–67 min) on the band gap of the films. The samples were characterized using X-ray diffraction (XRD), scanning electron microscope (SEM) and ultraviolet–visible spectroscopy (UV–vis) measurements. The optimal conditions for the deposition parameters of the CdS thin films have been found to be: pH 11, 361 of stirring speed and 55 min of deposition time. Under the optimal conditions theoretical (predicted) band gap of CdS (2.66 eV) was calculated using optimal coded values from the model and the theoretical value is good agreement with the value (2.72 eV) obtained by verification experiment.

  17. Exposures to conditioned flavours with different hedonic values induce contrasted behavioural and brain responses in pigs.

    Directory of Open Access Journals (Sweden)

    Caroline Clouard

    Full Text Available This study investigated the behavioural and brain responses towards conditioned flavours with different hedonic values in juvenile pigs. Twelve 30-kg pigs were given four three-day conditioning sessions: they received three different flavoured meals paired with intraduodenal (i.d. infusions of 15% glucose (F(Glu, lithium chloride (F(LiCl, or saline (control treatment, F(NaCl. One and five weeks later, the animals were subjected to three two-choice feeding tests without reinforcement to check the acquisition of a conditioned flavour preference or aversion. In between, the anaesthetised pigs were subjected to three (18FDG PET brain imaging coupled with an olfactogustatory stimulation with the conditioned flavours. During conditioning, the pigs spent more time lying inactive, and investigated their environment less after the F(LiCl than the F(NaCl or F(Glu meals. During the two-choice tests performed one and five weeks later, the F(NaCl and F(Glu foods were significantly preferred over the F(LICl food even in the absence of i.d. infusions. Surprisingly, the F(NaCl food was also preferred over the F(Glu food during the first test only, suggesting that, while LiCl i.d. infusions led to a strong flavour aversion, glucose infusions failed to induce flavour preference. As for brain imaging results, exposure to aversive or less preferred flavours triggered global deactivation of the prefrontal cortex, specific activation of the posterior cingulate cortex, as well as asymmetric brain responses in the basal nuclei and the temporal gyrus. In conclusion, postingestive visceral stimuli can modulate the flavour/food hedonism and further feeding choices. Exposure to flavours with different hedonic values induced metabolism differences in neural circuits known to be involved in humans in the characterization of food palatability, feeding motivation, reward expectation, and more generally in the regulation of food intake.

  18. Exposures to conditioned flavours with different hedonic values induce contrasted behavioural and brain responses in pigs.

    Science.gov (United States)

    Clouard, Caroline; Jouhanneau, Mélanie; Meunier-Salaün, Marie-Christine; Malbert, Charles-Henri; Val-Laillet, David

    2012-01-01

    This study investigated the behavioural and brain responses towards conditioned flavours with different hedonic values in juvenile pigs. Twelve 30-kg pigs were given four three-day conditioning sessions: they received three different flavoured meals paired with intraduodenal (i.d.) infusions of 15% glucose (F(Glu)), lithium chloride (F(LiCl)), or saline (control treatment, F(NaCl)). One and five weeks later, the animals were subjected to three two-choice feeding tests without reinforcement to check the acquisition of a conditioned flavour preference or aversion. In between, the anaesthetised pigs were subjected to three (18)FDG PET brain imaging coupled with an olfactogustatory stimulation with the conditioned flavours. During conditioning, the pigs spent more time lying inactive, and investigated their environment less after the F(LiCl) than the F(NaCl) or F(Glu) meals. During the two-choice tests performed one and five weeks later, the F(NaCl) and F(Glu) foods were significantly preferred over the F(LICl) food even in the absence of i.d. infusions. Surprisingly, the F(NaCl) food was also preferred over the F(Glu) food during the first test only, suggesting that, while LiCl i.d. infusions led to a strong flavour aversion, glucose infusions failed to induce flavour preference. As for brain imaging results, exposure to aversive or less preferred flavours triggered global deactivation of the prefrontal cortex, specific activation of the posterior cingulate cortex, as well as asymmetric brain responses in the basal nuclei and the temporal gyrus. In conclusion, postingestive visceral stimuli can modulate the flavour/food hedonism and further feeding choices. Exposure to flavours with different hedonic values induced metabolism differences in neural circuits known to be involved in humans in the characterization of food palatability, feeding motivation, reward expectation, and more generally in the regulation of food intake.

  19. Hydrological Responses to Land-Use Change Scenarios under Constant and Changed Climatic Conditions.

    Science.gov (United States)

    Zhang, Ling; Nan, Zhuotong; Yu, Wenjun; Ge, Yingchun

    2016-02-01

    This study quantified the hydrological responses to land-use change scenarios in the upper and middle Heihe River basin (HRB), northwest China, under constant and changed climatic conditions by combining a land-use/cover change model (dynamic conversion of land use and its effects, Dyna-CLUE) and a hydrological model (soil and water assessment tool, SWAT). Five land-use change scenarios, i.e., historical trend (HT), ecological protection (EP), strict ecological protection (SEP), economic development (ED), and rapid economic development (RED) scenarios, were established. Under constant climatic condition, hydrological variations are only induced by land-use changes in different scenarios. The changes in mean streamflow at the outlets of the upper and the middle HRB are not pronounced, although the different scenarios produce different outcomes. However, more pronounced changes are observed on a subbasin level. The frequency of extreme flood is projected to decrease under the SEP scenario, while under the other scenarios, no changes can be found. Two emission scenarios (A1B and B1) of three general circulation models (HadCM3, CGCM3, and CCSM3) were employed to generate future possible climatic conditions. Under changed climatic condition, hydrological variations are induced by the combination of land-use and climatic changes. The results indicate that the impacts of land-use changes become secondary when the changed climatic conditions have been considered. The frequencies of extreme flood and drought are projected to decrease and increase, respectively, under all climate scenarios. Although some agreements can be reached, pronounced difference of hydrological responses can be observed for different climate scenarios of different GCMs.

  20. Alleviation of response suppression to conditioned aversive stimuli by lesions of the dorsal noradrenergic bundle.

    Science.gov (United States)

    Tsaltas, E; Gray, J A; Fillenz, M

    1984-08-01

    Rats with neurotoxic lesions of the dorsal ascending noradrenergic bundle (DB) were compared with sham-operated (SH) controls on the acquisition, steady state and extinction of response suppression maintained by a classical (conditioned suppression) or an instrumental (discriminated punishment) contingency. DB lesions interfered neither with the acquisition of the reference response of sucrose-rewarded barpressing nor with unconditioned responding to the overhead flashing light subsequently used as a signal of shock. The acquisition of discriminated response suppression was also unaffected by the lesion under both types of contingency. However, once discriminated suppression had stabilized, both the conditioned and the discriminative stimulus used were significantly less effective in maintaining suppression in DB animals than in SH controls provided that low intensity footshock (0.2 mA) was used as the unconditioned stimulus (UCS). Upon increase of UCS intensity (to 0.5 mA) normal suppression was observed in the DB group under both contingencies. Extinction of the classical contingency reinstated the difference between DB and SH performance: DB lesion resulted in significantly faster extinction of fear. In contrast, extinction of the discriminated punishment contingency was unaffected by the lesion, although generalized response suppression dissipated faster in the DB than in the SH animals trained under this condition. Our results offer no support for the reinforcement hypothesis of DB function (normal acquisition of barpressing and of discriminated suppression of barpressing); mixed support (greater initial generalization of suppression in DB animals) and contradiction (more rapid extinction of conditioned suppression in DB animals) for the attentional hypothesis; and weak support (reduced suppression and more rapid extinction of suppression in DB animals, but only within limited experimental parameters) for the anxiety hypothesis of DB function. Hence none of

  1. Neurotoxic lesions of the dorsal and ventral hippocampus impair acquisition and expression of trace-conditioned fear-potentiated startle in rats.

    Science.gov (United States)

    Trivedi, Mehul A; Coover, Gary D

    2006-04-03

    Pavlovian delay conditioning, in which a conditioned stimulus (CS) and unconditioned stimulus (US) co-terminate, is thought to reflect non-declarative memory. In contrast, trace conditioning, in which the CS and US are temporally separate, is thought to reflect declarative memory. Hippocampal lesions impair acquisition and expression of trace conditioning measured by the conditioned freezing and eyeblink responses, while having little effect on the acquisition of delay conditioning. Recent evidence suggests that lesions of the ventral hippocampus (VH) impair conditioned fear under conditions in which dorsal hippocampal (DH) lesions have little effect. In the present study, we examined the time-course of fear expression after delay and trace conditioning using the fear-potentiated startle (FPS) reflex, and the effects of pre- and post-training lesions to the VH and DH on trace-conditioned FPS. We found that both delay- and trace-conditioned rats displayed significant FPS near the end of the CS relative to the unpaired control group. In contrast, trace-conditioned rats displayed significant FPS throughout the duration of the trace interval, whereas FPS decayed rapidly to baseline after CS offset in delay-conditioned rats. In experiment 2, both DH and VH lesions were found to significantly reduce the overall magnitude of FPS compared to the control group, however, no differences were found between the DH and VH groups. These findings support a role for both the DH and VH in trace fear conditioning, and suggest that the greater effect of VH lesions on conditioned fear might be specific to certain measures of fear.

  2. Recursive solution for dynamic response of one-dimensional structures with time-dependent boundary conditions

    International Nuclear Information System (INIS)

    Abadi, Mohammad Tahaye

    2015-01-01

    A recursive solution method is derived for the transient response of one-dimensional structures subjected to the general form of time dependent boundary conditions. Unlike previous solution methods that assumed the separation of variables, the present method involves formulating and solving the dynamic problems using the summation of two single-argument functions satisfying the motion equation. Based on boundary and initial conditions, a recursive procedure is derived to determine the single-argument functions. Such a procedure is applied to the general form of boundary conditions, and an analytical solution is derived by solving the recursive equation. The present solution method is implemented for base excitation problems, and the results are compared with those of the previous analytical solution and the Finite element (FE) analysis. The FE results converge to the present analytical solution, although considerable error is found in predicting a solution method on the basis of the separation of variables. The present analytical solution predicts the transient response for wave propagation problems in broadband excitation frequencies.

  3. Recursive solution for dynamic response of one-dimensional structures with time-dependent boundary conditions

    Energy Technology Data Exchange (ETDEWEB)

    Abadi, Mohammad Tahaye [Aerospace Research Institute, Tehran (Iran, Islamic Republic of)

    2015-10-15

    A recursive solution method is derived for the transient response of one-dimensional structures subjected to the general form of time dependent boundary conditions. Unlike previous solution methods that assumed the separation of variables, the present method involves formulating and solving the dynamic problems using the summation of two single-argument functions satisfying the motion equation. Based on boundary and initial conditions, a recursive procedure is derived to determine the single-argument functions. Such a procedure is applied to the general form of boundary conditions, and an analytical solution is derived by solving the recursive equation. The present solution method is implemented for base excitation problems, and the results are compared with those of the previous analytical solution and the Finite element (FE) analysis. The FE results converge to the present analytical solution, although considerable error is found in predicting a solution method on the basis of the separation of variables. The present analytical solution predicts the transient response for wave propagation problems in broadband excitation frequencies.

  4. Screening for Osmotic Stress Responses in Rice Varieties under Drought Condition

    Directory of Open Access Journals (Sweden)

    Simon Swapna

    2017-09-01

    Full Text Available Drought is the major abiotic stress factor that limits rice production worldwide. To evaluate the osmotic stress responses in rice varieties under drought condition, a total of 42 high-yielding rice varieties were collected from various research stations of Kerala Agricultural University in India. The experimental setup comprises of initial hydroponic treatments at different osmotic potentials, artificially induced by desired strengths of polyethylene glycol (PEG6000, and followed by the pot planted experiments in the rain-out-zone. The activities of antioxidant enzymes, relative water content, cell membrane stability, photosynthetic pigments, proline content, along with plant growth parameters of the varieties under drought condition were evaluated. Moreover, the standard scores of these rice varieties were assessed under stress and recovery conditions based on the scoring scale of the Standard Evaluation System for rice. Among the 42 rice varieties, we identified 2 rice varieties, Swarnaprabha and Kattamodan, with less leaf rolling, better drought recovery ability as well as relative water content, increased membrane stability index, osmolyte accumulation, and antioxidant enzyme activities pointed towards their degree of tolerance to drought stress. The positive adaptive responses of these rice varieties towards drought stress can be used in the genetic improvement of rice drought resistance breeding program.

  5. Dynamics of food availability, body condition and physiological stress response in breeding Black-legged Kittiwakes

    Science.gov (United States)

    Kitaysky, A.S.; Wingfield, J.C.; Piatt, John F.

    1999-01-01

    1. The seasonal dynamics of body condition (BC), circulating corticosterone levels (baseline, BL) and the adrenocortical response to acute stress (SR) were examined in long-lived Black-legged Kittiwakes, Rissa tridactyla, breeding at Duck (food-poor colony) and Gull (food-rich colony) Islands in lower Cook Inlet, Alaska. It was tested whether the dynamics of corticosterone levels reflect a seasonal change in bird physiological condition due to reproduction and/or variation in foraging conditions. 2. BC declined seasonally, and the decline was more pronounced in birds at the food-poor colony. BL and SR levels of corticosterone rose steadily through the reproductive season, and BL levels were significantly higher in birds on Duck island compared with those on Gull Island. During the egg-laying and chick-rearing stages, birds had lower SR on Duck Island than on Gull Island. 3. The results suggest that, in addition to a seasonal change in bird physiology during reproduction, local ecological factors such as food availability affect circulating levels of corticosterone and adrenal response to acute stress.

  6. Adaptation of postural responses during different standing perturbation conditions in individuals with incomplete spinal cord injury.

    Science.gov (United States)

    Thigpen, Mary T; Cauraugh, James; Creel, Gwen; Day, Kristin; Flynn, Sheryl; Fritz, Stacy; Frost, Shirley; Respess, Robert; Gardner-Smith, Portia; Brack, Mia; Behrman, Andrea

    2009-01-01

    Incomplete spinal cord injury (ISCI) frequently disrupts afferent and efferent neural pathways underlying co-requisite voluntary and involuntary muscle activation required for functional standing and walking. To understand involuntary postural control mechanisms necessary for standing, we compared eight individuals with ISCI to eight controls with no impairment. The aim of this study was to investigate anticipatory and reactive balance responses in individuals with ISCI. The ability to adapt to changes in balance conditions was assessed by monitoring automatic postural responses (APRs) during a series of expected and unexpected changes in perturbation direction (backward translation versus toes-up rotation). Both groups were able to modulate appropriately within one or two trials following an unexpected change in condition. Onset times of anterior tibialis and medial gastrocnemius (MG) were significantly slower in the ISCI group during expected and unexpected conditions. These findings demonstrate that persons with mild to moderate lower extremity sensorimotor deficits are able to generate and adapt APRs to a rapid and unexpected contextual change during a simple standing balance task.

  7. Determination of Critical Conditions for Puncturing Almonds Using Coupled Response Surface Methodology and Genetic Algorithm

    Directory of Open Access Journals (Sweden)

    Mahmood Mahmoodi-Eshkaftaki

    2013-01-01

    Full Text Available In this study, the effect of seed moisture content, probe diameter and loading velocity (puncture conditions on some mechanical properties of almond kernel and peeled almond kernel is considered to model a relationship between the puncture conditions and rupture energy. Furthermore, distribution of the mechanical properties is determined. The main objective is to determine the critical values of mechanical properties significant for peeling machines. The response surface methodology was used to find the relationship between the input parameters and the output responses, and the fitness function was applied to measure the optimal values using the genetic algorithm. Two-parameter Weibull function was used to describe the distribution of mechanical properties. Based on the Weibull parameter values, i.e. shape parameter (β and scale parameter (η calculated for each property, the mechanical distribution variations were completely described and it was confirmed that the mechanical properties are rule governed, which makes the Weibull function suitable for estimating their distributions. The energy model estimated using response surface methodology shows that the mechanical properties relate exponentially to the moisture, and polynomially to the loading velocity and probe diameter, which enabled successful estimation of the rupture energy (R²=0.94. The genetic algorithm calculated the critical values of seed moisture, probe diameter, and loading velocity to be 18.11 % on dry mass basis, 0.79 mm, and 0.15 mm/min, respectively, and optimum rupture energy of 1.97·10-³ J. These conditions were used for comparison with new samples, where the rupture energy was experimentally measured to be 2.68 and 2.21·10-³ J for kernel and peeled kernel, respectively, which was nearly in agreement with our model results.

  8. Transient response of a polymer electrolyte membrane fuel cell subjected to time-varying modulating conditions

    Energy Technology Data Exchange (ETDEWEB)

    Noorani, S.; Shamim, T. [Michigan-Dearborn Univ., Dearborn, MI (United States). Dept. of Mechanical Engineering

    2009-07-01

    In order for fuel cells to compete with internal combustion engines, they must have significant advantages in terms of overall efficiency, weight, packaging, safety and cost. A key requirement is its ability to operate under highly transient conditions during start-up, acceleration, and deceleration with stable performance. Therefore, a better understanding of fuel cell dynamic behaviour is needed along with better water management and distributions inside the cell. Therefore, this study investigated the effect of transient conditions on water distribution inside a polymer electrolyte membrane (PEM) cell. A macroscopic single-fuel cell based, one-dimensional, isothermal mathematical model was used to study the effect of modulating cell voltage on the water distribution of anode, cathode, catalyst layers, and membrane. Compared to other existing models, this model did not rely on the non-physical assumption of the uptake curve equilibrium between the pore vapour and ionomer water in the catalyst layers. Instead, the transition between the two phases was modeled as a finite-rate equilibration process. The modulating conditions were simulated by forcing the temporal variations in fuel cell voltage. The results revealed that cell voltage modulations cause a departure in the cell behaviour from its steady behaviour, and the finite-rate equilibration between the catalyst vapour and liquid water can be a factor in determining the cell response. The cell response is also affected by the modulating frequency and amplitude. The peak cell response was observed at low frequencies. Keywords: fuel cell, water transport, dynamic behaviour, numerical simulations. 9 refs., 1 tab., 5 figs.

  9. Reducing Conservatism in Aircraft Engine Response Using Conditionally Active Min-Max Limit Regulators

    Science.gov (United States)

    May, Ryan D.; Garg, Sanjay

    2012-01-01

    Current aircraft engine control logic uses a Min-Max control selection structure to prevent the engine from exceeding any safety or operational limits during transients due to throttle commands. This structure is inherently conservative and produces transient responses that are slower than necessary. In order to utilize the existing safety margins more effectively, a modification to this architecture is proposed, referred to as a Conditionally Active (CA) limit regulator. This concept uses the existing Min-Max architecture with the modification that limit regulators are active only when the operating point is close to a particular limit. This paper explores the use of CA limit regulators using a publicly available commercial aircraft engine simulation. The improvement in thrust response while maintaining all necessary safety limits is demonstrated in a number of cases.

  10. Application of Peleg's equation to describe creep responses of potatoes under constant and variable storage conditions.

    Science.gov (United States)

    Solomon, W K; Jindal, V K

    2017-06-01

    The application of Peleg's equation to characterize creep behavior of potatoes during storage was investigated. Potatoes were stored at 25, 15, 5C, and variable (fluctuating) temperature for 16 or 26 weeks. The Peleg equation adequately described the creep response of potatoes during storage at all storage conditions (R 2  = .97to .99). Peleg constant k 1 exhibited a significant (p creep responses during storage or processing will be potentially helpful to better understand the phenomenon. The model parameters from such model could be used to relate rheological properties of raw and cooked potatoes. Moreover, the model parameters could be used to establish relationship between instrumental and sensory attributes which will help in the prediction of sensory attributes from instrumental data. © 2016 Wiley Periodicals, Inc.

  11. Auditory event-related responses to diphthongs in different attention conditions

    DEFF Research Database (Denmark)

    Morris, David Jackson; Steinmetzger, Kurt; Tøndering, John

    2016-01-01

    The modulation of auditory event-related potentials (ERP) by attention generally results in larger amplitudes when stimuli are attended. We measured the P1-N1-P2 acoustic change complex elicited with synthetic overt (second formant, F2 = 1000 Hz) and subtle (F2 = 100 Hz) diphthongs, while subjects...... (i) attended to the auditory stimuli, (ii) ignored the auditory stimuli and watched a film, and (iii) diverted their attention to a visual discrimination task. Responses elicited by diphthongs where F2 values rose and fell were found to be different and this precluded their combined analysis....... Multivariate analysis of ERP components from the rising F2 changes showed main effects of attention on P2 amplitude and latency, and N1-P2 amplitude. P2 amplitude decreased by 40% between the attend and ignore conditions, and by 60% between the attend and divert conditions. The effect of diphthong magnitude...

  12. OPTIMIZATION OF MICROWAVE AND AIR DRYING CONDITIONS OF QUINCE (CYDONIA OBLONGA, MILLER USING RESPONSE SURFACE METHODOLOGY

    Directory of Open Access Journals (Sweden)

    Cem Baltacioglu

    2015-03-01

    Full Text Available Effects of slice thickness of quince (Cydonia oblonga Miller , microwave incident power and air drying temperature on antioxidant activity and total phenolic content of quince were investigated during drying in microwave and air drying. Optimum conditions were found to be: i for microwave drying, 285 W and 4.14 mm thick (maximum antioxidant activity and 285 W and 6.85 mm thick (maximum total phenolic content, and ii for air drying, 75 ºC and 1.2 mm thick (both maximum antioxidant activity and total phenolic content. Drying conditions were optimized by using the response surface methodology. 13 experiments were carried out considering incident microwave powers from 285 to 795 W, air temperature from 46 to 74 ºC and slice thickness from 1.2 to 6.8 mm.

  13. Avian migrants adjust migration in response to environmental conditions en route

    DEFF Research Database (Denmark)

    Tøttrup, Anders P; Thorup, Kasper; Rainio, Kalle

    2008-01-01

    The onset of migration in birds is assumed to be primarily under endogenous control in long-distance migrants. Recently, climate changes appear to have been driving a rapid change in breeding area arrival. However, little is known about the climatic factors affecting migratory birds during...... covering the entire migration period every year from observatories located in the Middle East and northern Europe, we show that passage of the Sahara Desert is delayed and correlated with improved conditions in the wintering areas. By contrast, migrants travel more rapidly through Europe, and adjust...... the migration cycle, or whether recently reported phenological changes are caused by plastic behavioural responses or evolutionary change. Here, we investigate how environmental conditions in the wintering areas as well as en route towards breeding areas affect timing of migration. Using data from 1984 to 2004...

  14. Review of parameters influencing the structural response of a submerged body under cavitation conditions

    International Nuclear Information System (INIS)

    Escaler, X; De La Torre, O; Farhat, M

    2015-01-01

    Submerged structures that operate under extreme flows are prone to suffer large scale cavitation attached to their surfaces. Under such conditions the added mass effects differ from the expected ones in pure liquids. Moreover, the existence of small gaps between the structure and surrounding bodies filled with fluid also influence the dynamic response. A series of experiments and numerical simulations have been carried out with a truncated NACA0009 hydrofoil mounted as a cantilever beam at the LMH-EPFL cavitation tunnel. The three first modes of vibration have been determined and analysed under various hydrodynamic conditions ranging from air and still water to partial cavitation and supercavitation. A remote nonintrusive excitation system with piezoelectric patches has been used for the experiments. The effects of the cavity properties and the lateral gap size on the natural frequencies and mode shapes have been determined. As a result, the significance of several parameters in the design of such structures is discussed. (paper)

  15. Review of parameters influencing the structural response of a submerged body under cavitation conditions

    Science.gov (United States)

    Escaler, X.; De La Torre, O.; Farhat, M.

    2015-12-01

    Submerged structures that operate under extreme flows are prone to suffer large scale cavitation attached to their surfaces. Under such conditions the added mass effects differ from the expected ones in pure liquids. Moreover, the existence of small gaps between the structure and surrounding bodies filled with fluid also influence the dynamic response. A series of experiments and numerical simulations have been carried out with a truncated NACA0009 hydrofoil mounted as a cantilever beam at the LMH-EPFL cavitation tunnel. The three first modes of vibration have been determined and analysed under various hydrodynamic conditions ranging from air and still water to partial cavitation and supercavitation. A remote nonintrusive excitation system with piezoelectric patches has been used for the experiments. The effects of the cavity properties and the lateral gap size on the natural frequencies and mode shapes have been determined. As a result, the significance of several parameters in the design of such structures is discussed.

  16. Model development and optimization of operating conditions to maximize PEMFC performance by response surface methodology

    International Nuclear Information System (INIS)

    Kanani, Homayoon; Shams, Mehrzad; Hasheminasab, Mohammadreza; Bozorgnezhad, Ali

    2015-01-01

    Highlights: • The optimization of the operating parameters in a serpentine PEMFC is done using RSM. • The RSM model can predict the cell power over the wide range of operating conditions. • St-An, St-Ca and RH-Ca have an optimum value to obtain the best performance. • The interactions of the operating conditions affect the output power significantly. • The cathode and anode stoichiometry are the most effective parameters on the power. - Abstract: Optimization of operating conditions to obtain maximum power in PEMFCs could have a significant role to reduce the costs of this emerging technology. In the present experimental study, a single serpentine PEMFC is used to investigate the effects of operating conditions on the electrical power production of the cell. Four significant parameters including cathode stoichiometry, anode stoichiometry, gases inlet temperature, and cathode relative humidity are studied using Design of Experiment (DOE) to obtain an optimal power. Central composite second order Response Surface Methodology (RSM) is used to model the relationship between goal function (power) and considered input parameters (operating conditions). Using this statistical–mathematical method leads to obtain a second-order equation for the cell power. This model considers interactions and quadratic effects of different operating conditions and predicts the maximum or minimum power production over the entire working range of the parameters. In this range, high stoichiometry of cathode and low stoichiometry of anode results in the minimum cell power and contrary the medium range of fuel and oxidant stoichiometry leads to the maximum power. Results show that there is an optimum value for the anode stoichiometry, cathode stoichiometry and relative humidity to reach the best performance. The predictions of the model are evaluated by experimental tests and they are in a good agreement for different ranges of the parameters

  17. Isoprenoid emission response to changing light conditions of English oak, European beech and Norway spruce

    Directory of Open Access Journals (Sweden)

    Y. van Meeningen

    2017-09-01

    Full Text Available Light is an important environmental factor controlling biogenic volatile organic compound (BVOC emissions, but in natural conditions its impact is hard to separate from other influential factors such as temperature. We studied the light response of foliar BVOC emissions, photosynthesis and stomatal conductance on three common European tree species, namely English oak (Quercus robur, European beech (Fagus sylvatica and two provenances of Norway spruce (Picea abies in Taastrup, Denmark. Leaf scale measurements were performed on the lowest positioned branches of the tree in July 2015. Light intensity was increased in four steps (0, 500, 1000 and 1500 µmol m−2 s−1, whilst other chamber conditions such as temperature, humidity and CO2 levels were fixed. Whereas the emission rate differed between individuals of the same species, the relative contributions of compounds to the total isoprenoid emission remained similar. Whilst some compounds were species specific, the compounds α-pinene, camphene, 3-carene, limonene and eucalyptol were emitted by all of the measured tree species. Some compounds, like isoprene and sabinene, showed an increasing emission response with increasing light intensity, whereas other compounds, like camphene, had no significant emission response to light for most of the measured trees. English oak and European beech showed high light-dependent emission fractions from isoprene and sabinene, but other emitted compounds were light independent. For the two provenances of Norway spruce, the compounds α-pinene, 3-carene and eucalyptol showed high light-dependent fractions for many of the measured trees. This study highlights differences between compound emissions in their response to a change in light and a possible light independence for certain compounds, which might be valid for a wider range of tree species. This information could be of importance when improving emission models and to further emphasize the

  18. Isoprenoid emission response to changing light conditions of English oak, European beech and Norway spruce

    Science.gov (United States)

    van Meeningen, Ylva; Schurgers, Guy; Rinnan, Riikka; Holst, Thomas

    2017-09-01

    Light is an important environmental factor controlling biogenic volatile organic compound (BVOC) emissions, but in natural conditions its impact is hard to separate from other influential factors such as temperature. We studied the light response of foliar BVOC emissions, photosynthesis and stomatal conductance on three common European tree species, namely English oak (Quercus robur), European beech (Fagus sylvatica) and two provenances of Norway spruce (Picea abies) in Taastrup, Denmark. Leaf scale measurements were performed on the lowest positioned branches of the tree in July 2015. Light intensity was increased in four steps (0, 500, 1000 and 1500 µmol m-2 s-1), whilst other chamber conditions such as temperature, humidity and CO2 levels were fixed. Whereas the emission rate differed between individuals of the same species, the relative contributions of compounds to the total isoprenoid emission remained similar. Whilst some compounds were species specific, the compounds α-pinene, camphene, 3-carene, limonene and eucalyptol were emitted by all of the measured tree species. Some compounds, like isoprene and sabinene, showed an increasing emission response with increasing light intensity, whereas other compounds, like camphene, had no significant emission response to light for most of the measured trees. English oak and European beech showed high light-dependent emission fractions from isoprene and sabinene, but other emitted compounds were light independent. For the two provenances of Norway spruce, the compounds α-pinene, 3-carene and eucalyptol showed high light-dependent fractions for many of the measured trees. This study highlights differences between compound emissions in their response to a change in light and a possible light independence for certain compounds, which might be valid for a wider range of tree species. This information could be of importance when improving emission models and to further emphasize the discussion regarding light or

  19. Disrupting astrocyte–neuron lactate transfer persistently reduces conditioned responses to cocaine

    KAUST Repository

    Boury-Jamot, B

    2015-10-27

    A central problem in the treatment of drug addiction is the high risk of relapse often precipitated by drug-associated cues. The transfer of glycogen-derived lactate from astrocytes to neurons is required for long-term memory. Whereas blockade of drug memory reconsolidation represents a potential therapeutic strategy, the role of astrocyte–neuron lactate transport in long-term conditioning has received little attention. By infusing an inhibitor of glycogen phosphorylase into the basolateral amygdala of rats, we report that disruption of astrocyte-derived lactate not only transiently impaired the acquisition of a cocaine-induced conditioned place preference but also persistently disrupted an established conditioning. The drug memory was rescued by L-Lactate co-administration through a mechanism requiring the synaptic plasticity-related transcription factor Zif268 and extracellular signal-regulated kinase (ERK) signalling pathway but not the brain-derived neurotrophic factor (Bdnf). The long-term amnesia induced by glycogenolysis inhibition and the concomitant decreased expression of phospho-ERK were both restored with L-Lactate co-administration. These findings reveal a critical role for astrocyte-derived lactate in positive memory formation and highlight a novel amygdala-dependent reconsolidation process, whose disruption may offer a novel therapeutic target to reduce the long-lasting conditioned responses to cocaine.

  20. Disrupting astrocyte–neuron lactate transfer persistently reduces conditioned responses to cocaine

    KAUST Repository

    Boury-Jamot, B; Carrard, A; Martin, J L; Halfon, O; Magistretti, Pierre J.; Boutrel, B

    2015-01-01

    A central problem in the treatment of drug addiction is the high risk of relapse often precipitated by drug-associated cues. The transfer of glycogen-derived lactate from astrocytes to neurons is required for long-term memory. Whereas blockade of drug memory reconsolidation represents a potential therapeutic strategy, the role of astrocyte–neuron lactate transport in long-term conditioning has received little attention. By infusing an inhibitor of glycogen phosphorylase into the basolateral amygdala of rats, we report that disruption of astrocyte-derived lactate not only transiently impaired the acquisition of a cocaine-induced conditioned place preference but also persistently disrupted an established conditioning. The drug memory was rescued by L-Lactate co-administration through a mechanism requiring the synaptic plasticity-related transcription factor Zif268 and extracellular signal-regulated kinase (ERK) signalling pathway but not the brain-derived neurotrophic factor (Bdnf). The long-term amnesia induced by glycogenolysis inhibition and the concomitant decreased expression of phospho-ERK were both restored with L-Lactate co-administration. These findings reveal a critical role for astrocyte-derived lactate in positive memory formation and highlight a novel amygdala-dependent reconsolidation process, whose disruption may offer a novel therapeutic target to reduce the long-lasting conditioned responses to cocaine.

  1. Physiological responses to ocean acidification and warming synergistically reduce condition of the common cockle Cerastoderma edule.

    Science.gov (United States)

    Ong, E Z; Briffa, M; Moens, T; Van Colen, C

    2017-09-01

    The combined effect of ocean acidification and warming on the common cockle Cerastoderma edule was investigated in a fully crossed laboratory experiment. Survival of the examined adult organisms remained high and was not affected by elevated temperature (+3 °C) or lowered pH (-0.3 units). However, the morphometric condition index of the cockles incubated under high pCO 2 conditions (i.e. combined warming and acidification) was significantly reduced after six weeks of incubation. Respiration rates increased significantly under low pH, with highest rates measured under combined warm and low pH conditions. Calcification decreased significantly under low pH while clearance rates increased significantly under warm conditions and were generally lower in low pH treatments. The observed physiological responses suggest that the reduced food intake under hypercapnia is insufficient to support the higher energy requirements to compensate for the higher costs for basal maintenance and growth in future high pCO 2 waters. Copyright © 2017 Elsevier Ltd. All rights reserved.

  2. Water Age Responses to Weather Conditions in a Hyper-Eutrophic Channel Reservoir in Southern China

    Directory of Open Access Journals (Sweden)

    Wei Du

    2016-08-01

    Full Text Available Channel reservoirs have the characteristics of both rivers and lakes, in which hydrodynamic conditions and the factors affecting the eutrophication process are complex and highly affected by weather conditions. Water age at any location in the reservoir is used as an indicator for describing the spatial and temporal variations of water exchange and nutrient transport. The hyper-eutrophic Changtan Reservoir (CTR in Southern China was investigated. Three weather conditions including wet, normal, and dry years were considered for assessing the response of water age by using the coupled watershed model Soil Water Assessment Tool (SWAT and the three-dimensional hydrodynamic model Environmental Fluid Hydrodynamic Code (EFDC. The results showed that the water age in CTR varied tremendously under different weather conditions. The averaged water ages at the downstream of CTR were 3 d, 60 d, and 110 d, respectively in the three typical wet, normal, and dry years. The highest water ages at the main tributary were >70 d, >100 d, and >200 d, respectively. The spatial distribution of water ages in the tributaries and the reservoir were mainly affected by precipitation. This paper provides useful information on water exchange and transport pathways in channel reservoir, which will be helpful in understanding nutrient dynamics for controlling algal blooms.

  3. Experimental Evaluation of Grid Support Enabled PV Inverter Response to Abnormal Grid Conditions: Preprint

    Energy Technology Data Exchange (ETDEWEB)

    Nelson, Austin; Martin, Gregory; Hurtt, James

    2017-05-08

    As revised interconnection standards for grid-tied photovoltaic (PV) inverters address new advanced grid support functions (GSFs), there is increasing interest in inverter performance in the case of abnormal grid conditions. The growth of GSF-enabled inverters has outpaced the industry standards that define their operation, although recently published updates to UL1741 with Supplement SA define test conditions for GSFs such as volt-var control, frequency-watt control, and volt-age/frequency ride-through, among others. A comparative experimental evaluation has been completed on four commercially available, three-phase PV inverters in the 24.0-39.8 kVA power range on their GSF capability and the effect on abnormal grid condition response. This study examines the impact particular GSF implementations have on run-on times during islanding conditions, peak voltages in load rejection overvoltage scenarios, and peak currents during single-phase and three-phase fault events for individual inverters. This report reviews comparative test data, which shows that GSFs have little impact on the metrics of interest in most tests cases.

  4. Operant Conditioning in Honey Bees (Apis mellifera L.): The Cap Pushing Response.

    Science.gov (United States)

    Abramson, Charles I; Dinges, Christopher W; Wells, Harrington

    2016-01-01

    The honey bee has been an important model organism for studying learning and memory. More recently, the honey bee has become a valuable model to understand perception and cognition. However, the techniques used to explore psychological phenomena in honey bees have been limited to only a few primary methodologies such as the proboscis extension reflex, sting extension reflex, and free flying target discrimination-tasks. Methods to explore operant conditioning in bees and other invertebrates are not as varied as with vertebrates. This may be due to the availability of a suitable response requirement. In this manuscript we offer a new method to explore operant conditioning in honey bees: the cap pushing response (CPR). We used the CPR to test for difference in learning curves between novel auto-shaping and more traditional explicit-shaping. The CPR protocol requires bees to exhibit a novel behavior by pushing a cap to uncover a food source. Using the CPR protocol we tested the effects of both explicit-shaping and auto-shaping techniques on operant conditioning. The goodness of fit and lack of fit of these data to the Rescorla-Wagner learning-curve model, widely used in classical conditioning studies, was tested. The model fit well to both control and explicit-shaping results, but only for a limited number of trials. Learning ceased rather than continuing to asymptotically approach the physiological most accurate possible. Rate of learning differed between shaped and control bee treatments. Learning rate was about 3 times faster for shaped bees, but for all measures of proficiency control and shaped bees reached the same level. Auto-shaped bees showed one-trial learning rather than the asymptotic approach to a maximal efficiency. However, in terms of return-time, the auto-shaped bees' learning did not carry over to the covered-well test treatments.

  5. XBeach-G: a tool for predicting gravel barrier response to extreme storm conditions

    Science.gov (United States)

    Masselink, Gerd; Poate, Tim; McCall, Robert; Roelvink, Dano; Russell, Paul; Davidson, Mark

    2014-05-01

    Gravel beaches protect low-lying back-barrier regions from flooding during storm events and their importance to society is widely acknowledged. Unfortunately, breaching and extensive storm damage has occurred at many gravel sites and this is likely to increase as a result of sea-level rise and enhanced storminess due to climate change. Limited scientific guidance is currently available to provide beach managers with operational management tools to predict the response of gravel beaches to storms. The New Understanding and Prediction of Storm Impacts on Gravel beaches (NUPSIG) project aims to improve our understanding of storm impacts on gravel coastal environments and to develop a predictive capability by modelling these impacts. The NUPSIG project uses a 5-pronged approach to address its aim: (1) analyse hydrodynamic data collected during a proto-type laboratory experiment on a gravel beach; (2) collect hydrodynamic field data on a gravel beach under a range of conditions, including storm waves with wave heights up to 3 m; (3) measure swash dynamics and beach response on 10 gravel beaches during extreme wave conditions with wave heights in excess of 3 m; (4) use the data collected under 1-3 to develop and validate a numerical model to model hydrodynamics and morphological response of gravel beaches under storm conditions; and (5) develop a tool for end-users, based on the model formulated under (4), for predicting storm response of gravel beaches and barriers. The aim of this presentation is to present the key results of the NUPSIG project and introduce the end-user tool for predicting storm response on gravel beaches. The model is based on the numerical model XBeach, and different forcing scenarios (wave and tides), barrier configurations (dimensions) and sediment characteristics are easily uploaded for model simulations using a Graphics User Interface (GUI). The model can be used to determine the vulnerability of gravel barriers to storm events, but can also be

  6. Skin Conductance Responses and Neural Activations During Fear Conditioning and Extinction Recall Across Anxiety Disorders.

    Science.gov (United States)

    Marin, Marie-France; Zsido, Rachel G; Song, Huijin; Lasko, Natasha B; Killgore, William D S; Rauch, Scott L; Simon, Naomi M; Milad, Mohammed R

    2017-06-01

    The fear conditioning and extinction neurocircuitry has been extensively studied in healthy and clinical populations, with a particular focus on posttraumatic stress disorder. Despite significant overlap of symptoms between posttraumatic stress disorder and anxiety disorders, the latter has received less attention. Given that dysregulated fear levels characterize anxiety disorders, examining the neural correlates of fear and extinction learning may shed light on the pathogenesis of underlying anxiety disorders. To investigate the psychophysiological and neural correlates of fear conditioning and extinction recall in anxiety disorders and to document how these features differ as a function of multiple diagnoses or anxiety severity. This investigation was a cross-sectional, case-control, functional magnetic resonance imaging study at an academic medical center. Participants were healthy controls and individuals with at least 1 of the following anxiety disorders: generalized anxiety disorder, social anxiety disorder, specific phobia, and panic disorder. The study dates were between March 2013 and May 2015. Two-day fear conditioning and extinction paradigm. Skin conductance responses, blood oxygenation level-dependent responses, trait anxiety scores from the State Trait Anxiety Inventory-Trait Form, and functional connectivity. This study included 21 healthy controls (10 women) and 61 individuals with anxiety disorders (36 women). P values reported for the neuroimaging results are all familywise error corrected. Skin conductance responses during extinction recall did not differ between individuals with anxiety disorders and healthy controls (ηp2 = 0.001, P = .79), where ηp2 is partial eta squared. The anxiety group had lower activation of the ventromedial prefrontal cortex (vmPFC) during extinction recall (ηp2 = 0.178, P = .02). A similar hypoactive pattern was found during early conditioning (ηp2 = 0.106, P = .009). The vmPFC hypoactivation

  7. Response of unirradiated and irradiated PWR fuel rods tested under power-cooling-mismatch conditions

    International Nuclear Information System (INIS)

    MacDonald, P.E.; Quapp, W.J.; Martinson, Z.R.; McCardell, R.K.; Mehner, A.S.

    1978-01-01

    This report summarizes the results from the single-rod power-cooling-mismatch (PCM) and irradiation effects (IE) tests conducted to date in the Power Burst Facility (PBF) at the U.S. DOE Idaho National Engineering Laboratory. This work was performed for the U.S. NRC under contact to the Department of Energy. These tests are part of the NRC Fuel Behavior Program, which is designed to provide data for the development and verification of analytical fuel behavior models that are used to predict fuel response to abnormal or postulated accident conditions in commercial LWRs. The mechanical, chemical and thermal response of both previously unirradiated and previously irradiated LWR-type fuel rods tested under power-cooling-mismatch condition is discussed. A brief description of the test designs is presented. The results of the PCM thermal-hydraulic studies are summarized. Primary emphasis is placed on the behavior of the fuel and cladding during and after stable film boiling. (orig.) [de

  8. Statistical optimization for alkali pretreatment conditions of narrow-leaf cattail by response surface methodology

    Directory of Open Access Journals (Sweden)

    Arrisa Ruangmee

    2013-08-01

    Full Text Available Response surface methodology with central composite design was applied to optimize alkali pretreatment of narrow-leafcattail (Typha angustifolia. Joint effects of three independent variables; NaOH concentration (1-5%, temperature (60-100 ºC,and reaction time (30-150 min, were investigated to evaluate the increase in and the improvement of cellulosic componentscontained in the raw material after pretreatment. The combined optimum condition based on the cellulosic content obtainedfrom this study is: a concentration of 5% NaOH, a reaction time of 120 min, and a temperature of 100 ºC. This result has beenanalyzed employing ANOVA with a second order polynomial equation. The model was found to be significant and was able topredict accurately the response of strength at less than 5% error. Under this combined optimal condition, the desirable cellulosic content in the sample increased from 38.5 to 68.3%, while the unfavorable hemicellulosic content decreased from 37.6 to7.3%.

  9. Acquisition, consolidation, reconsolidation, and extinction of eyelid conditioning responses require de novo protein synthesis.

    Science.gov (United States)

    Inda, Mari Carmen; Delgado-García, José María; Carrión, Angel Manuel

    2005-02-23

    Memory, as measured by changes in an animal's behavior some time after learning, is a reflection of many processes. Here, using a trace paradigm, in mice we show that de novo protein synthesis is required for acquisition, consolidation, reconsolidation, and extinction of classically conditioned eyelid responses. Two critical periods of protein synthesis have been found: the first, during training, the blocking of which impaired acquisition; and the second, lasting the first 4 h after training, the blocking of which impaired consolidation. The process of reconsolidation was sensitive to protein synthesis inhibition if anisomycin was injected before or just after the reactivation session. Furthermore, extinction was also dependent on protein synthesis, following the same temporal course as that followed during acquisition and consolidation. This last fact reinforces the idea that extinction is an active learning process rather than a passive event of forgetting. Together, these findings demonstrate that all of the different stages of memory formation involved in the classical conditioning of eyelid responses are dependent on protein synthesis.

  10. The metabolic response of Candida albicans to farnesol under hyphae-inducing conditions.

    Science.gov (United States)

    Han, Ting-Li; Cannon, Richard D; Villas-Bôas, Silas G

    2012-12-01

    Farnesol is a quorum-sensing molecule (QSM) produced, and sensed, by the polymorphic fungus, Candida albicans. This cell-to-cell communication molecule is known to suppress the hyphal formation of C. albicans at high cell density. Despite many studies investigating the signalling mechanisms by which QSMs influence the morphogenesis of C. albicans, the downstream metabolic effect of these signalling pathways in response to farnesol-mediated morphogenesis remains obscure. Here, we have used metabolomics to investigate the metabolic response of C. albicans upon exposure to farnesol under hyphae-inducing conditions. We have found a general up-regulation of central carbon metabolic pathways when hyphal formation was suppressed by farnesol evidenced by a considerably larger number of central carbon metabolic intermediates detected under this condition at an overall lower intracellular level. By combining the metabolic profiles from farnesol-exposed cells with previous metabolomics data for C. albicans undergoing morphogenesis, we have identified several metabolic pathways that are likely to be associated with the morphogenetic process of C. albicans, as well as metabolic pathways such as those involved in lipid metabolism that appeared to be specifically affected by farnesol. Therefore, our results provide important new insights into the metabolic role of farnesol in C. albicans metabolism. © 2012 Federation of European Microbiological Societies. Published by Blackwell Publishing Ltd. All rights reserved.

  11. Embryo transcriptome response to environmental factors: implication for its survival under suboptimal conditions.

    Science.gov (United States)

    Salilew-Wondim, Dessie; Tesfaye, Dawit; Hoelker, Michael; Schellander, Karl

    2014-09-01

    After its formation, the mammalian zygote undergoes a series of morphological, physiological and biochemical alterations prior to undergoing cell differentiation. The zygote is then transformed into a complex multicellular organism in a defined time window which may differ between species. These orderly embryonic developmental events are tightly regulated by temporal and spatial activation and/or deactivation of genes and gene products. This phenomenon may in turn be dependent on the intrinsic characteristics of the embryo itself, the physiological and biochemical composition of the maternal environment or by in vitro culture condition. In fact, when embryos are subjected to suboptimal culture condition, some of the embryos may escape the environmental stress by activating certain transcripts and some others which are unable to activate anti-stress agents may die or exhibit abnormal development. This phenomenon may partly depend on transcripts and proteins stored during oogenesis. Indeed after embryonic genome activation, the embryo destiny is governed by its own transcripts and protein synthesized over time. Therefore, this review begins by highlighting the type and quality of transcripts accumulated or degraded during oogenesis and its impact on the embryo survival. Thereafter, emphasis is given to the transcriptome response of preimplantation embryos to suboptimal culture conditions. In addition, the long term effect of preimplantation culture environment on the transcriptome response embryos/fetus during peri and post implantation has been addressed. Finally, a brief summary of the epigenetic control of culture induced genetic variation of the embryos has been highlighted. Copyright © 2014 Elsevier B.V. All rights reserved.

  12. Responses of five Mediterranean halophytes to seasonal changes in environmental conditions.

    Science.gov (United States)

    Gil, Ricardo; Bautista, Inmaculada; Boscaiu, Monica; Lidón, Antonio; Wankhade, Shantanu; Sánchez, Héctor; Llinares, Josep; Vicente, Oscar

    2014-08-19

    In their natural habitats, different mechanisms may contribute to the tolerance of halophytes to high soil salinity and other abiotic stresses, but their relative contribution and ecological relevance, for a given species, remain largely unknown. We studied the responses to changing environmental conditions of five halophytes (Sarcocornia fruticosa, Inula crithmoides, Plantago crassifolia, Juncus maritimus and J. acutus) in a Mediterranean salt marsh, from summer 2009 to autumn 2010. A principal component analysis was used to correlate soil and climatic data with changes in the plants' contents of chemical markers associated with stress responses: ions, osmolytes, malondialdehyde (MDA, a marker of oxidative stress) and antioxidant systems. Stress tolerance in S. fruticosa, I. crithmoides and P. crassifolia (all succulent dicots) seemed to depend mostly on the transport of ions to aerial parts and the biosynthesis of specific osmolytes, whereas both Juncus species (monocots) were able to avoid accumulation of toxic ions, maintaining relatively high K(+)/Na(+) ratios. For the most salt-tolerant taxa (S. fruticosa and I. crithmoides), seasonal variations of Na(+), Cl(-), K(+) and glycine betaine, their major osmolyte, did not correlate with environmental parameters associated with salt or water stress, suggesting that their tolerance mechanisms are constitutive and relatively independent of external conditions, although they could be mediated by changes in the subcellular compartmentalization of ions and compatible osmolytes. Proline levels were too low in all the species to possibly have any effect on osmotic adjustment. However-except for P. crassifolia-proline may play a role in stress tolerance based on its 'osmoprotectant' functions. No correlation was observed between the degree of environmental stress and the levels of MDA or enzymatic and non-enzymatic antioxidants, indicating that the investigated halophytes are not subjected to oxidative stress under natural

  13. Responses of Two Invasive Plants Under Various Microclimate Conditions in the Seoul Metropolitan Region

    Science.gov (United States)

    Song, Uhram; Mun, Saeromi; Ho, Chang-Hoi; Lee, Eun Ju

    2012-06-01

    The possible consequences of global warming on plant communities and ecosystems have wide-ranging ramifications. We examined how environmental change affects plant growth as a function of the variations in the microclimate along an urban-suburban climate gradient for two allergy-inducing, invasive plants, Humulus japonicus and Ambrosia artemisiifolia var. elatior. The environmental factors and plant growth responses were measured at two urban sites (Gangbuk and Seongbuk) and two suburban sites (Goyang and Incheon) around Seoul, South Korea. The mean temperatures and CO2 concentrations differed significantly between the urban (14.8 °C and 439 ppm CO2) and suburban (13.0 °C and 427 ppm CO2) sites. The soil moisture and nitrogen contents of the suburban sites were higher than those at the urban sites, especially for the Goyang site. The two invasive plants showed significantly higher biomasses and nitrogen contents at the two urban sites. We conducted experiments in a greenhouse to confirm the responses of the plants to increased temperatures, and we found consistently higher growth rates under conditions of higher temperatures. Because we controlled the other factors, the better performance of the two invasive plants appears to be primarily attributable to their responses to temperature. Our study demonstrates that even small temperature changes in the environment can confer significant competitive advantages to invasive species. As habitats become urbanized and warmer, these invasive plants should be able to displace native species, which will adversely affect people living in these areas.

  14. Optimization of Electrochemical Treatment Process Conditions for Distillery Effluent Using Response Surface Methodology

    Directory of Open Access Journals (Sweden)

    P. Arulmathi

    2015-01-01

    Full Text Available Distillery industry is recognized as one of the most polluting industries in India with a large amount of annual effluent production. In this present study, the optimization of electrochemical treatment process variables was reported to treat the color and COD of distillery spent wash using Ti/Pt as an anode in a batch mode. Process variables such as pH, current density, electrolysis time, and electrolyte dose were selected as operation variables and chemical oxygen demand (COD and color removal efficiency were considered as response variable for optimization using response surface methodology. Indirect electrochemical-oxidation process variables were optimized using Box-Behnken response surface design (BBD. The results showed that electrochemical treatment process effectively removed the COD (89.5% and color (95.1% of the distillery industry spent wash under the optimum conditions: pH of 4.12, current density of 25.02 mA/cm2, electrolysis time of 103.27 min, and electrolyte (NaCl concentration of 1.67 g/L, respectively.

  15. Extreme Hypoxic Conditions Induce Selective Molecular Responses and Metabolic Reset in Detached Apple Fruit

    Science.gov (United States)

    Cukrov, Dubravka; Zermiani, Monica; Brizzolara, Stefano; Cestaro, Alessandro; Licausi, Francesco; Luchinat, Claudio; Santucci, Claudio; Tenori, Leonardo; Van Veen, Hans; Zuccolo, Andrea; Ruperti, Benedetto; Tonutti, Pietro

    2016-01-01

    The ripening physiology of detached fruit is altered by low oxygen conditions with profound effects on quality parameters. To study hypoxia-related processes and regulatory mechanisms, apple (Malus domestica, cv Granny Smith) fruit, harvested at commercial ripening, were kept at 1°C under normoxic (control) and hypoxic (0.4 and 0.8 kPa oxygen) conditions for up to 60 days. NMR analyses of cortex tissue identified eight metabolites showing significantly different accumulations between samples, with ethanol and alanine displaying the most pronounced difference between hypoxic and normoxic treatments. A rapid up-regulation of alcohol dehydrogenase and pyruvate-related metabolism (lactate dehydrogenase, pyruvate decarboxylase, alanine aminotransferase) gene expression was detected under both hypoxic conditions with a more pronounced effect induced by the lowest (0.4 kPa) oxygen concentration. Both hypoxic conditions negatively affected ACC synthase and ACC oxidase transcript accumulation. Analysis of RNA-seq data of samples collected after 24 days of hypoxic treatment identified more than 1000 genes differentially expressed when comparing 0.4 vs. 0.8 kPa oxygen concentration samples. Genes involved in cell-wall, minor and major CHO, amino acid and secondary metabolisms, fermentation and glycolysis as well as genes involved in transport, defense responses, and oxidation-reduction appeared to be selectively affected by treatments. The lowest oxygen concentration induced a higher expression of transcription factors belonging to AUX/IAA, WRKY, HB, Zinc-finger families, while MADS box family genes were more expressed when apples were kept under 0.8 kPa oxygen. Out of the eight group VII ERF members present in apple genome, two genes showed a rapid up-regulation under hypoxia, and western blot analysis showed that apple MdRAP2.12 proteins were differentially accumulated in normoxic and hypoxic samples, with the highest level reached under 0.4 kPa oxygen. These data suggest

  16. Occupants' adaptive responses and perception of thermal environment in naturally conditioned university classrooms

    Energy Technology Data Exchange (ETDEWEB)

    Yao, Runming [The School of Construction Management and Engineering, The University of Reading, Whiteknights, PO Box 219, Reading RG6 6AW (United Kingdom); The Faculty of Urban Construction and Environmental Engineering, Chongqing University, Chongqing 400042 (China); Liu, Jing [The School of Construction Management and Engineering, The University of Reading, Whiteknights, PO Box 219, Reading RG6 6AW (United Kingdom); Li, Baizhan [The Faculty of Urban Construction and Environmental Engineering, Chongqing University, Chongqing 400042 (China); Key Laboratory of the Three Gorges Reservoir Region' s Eco-Environment (Ministry of Education), Chongqing University, Chongqing 400042 (China)

    2010-03-15

    A year-long field study of the thermal environment in university classrooms was conducted from March 2005 to May 2006 in Chongqing, China. This paper presents the occupants' thermal sensation votes and discusses the occupants' adaptive response and perception of the thermal environment in a naturally conditioned space. Comparisons between the Actual Mean Vote (AMV) and Predicted Mean Vote (PMV) have been made as well as between the Actual Percentage of Dissatisfied (APD) and Predicted Percentage of Dissatisfied (PPD). The adaptive thermal comfort zone for the naturally conditioned space for Chongqing, which has hot summer and cold winter climatic characteristics, has been proposed based on the field study results. The Chongqing adaptive comfort range is broader than that of the ASHRAE Standard 55-2004 in general, but in the extreme cold and hot months, it is narrower. The thermal conditions in classrooms in Chongqing in summer and winter are severe. Behavioural adaptation such as changing clothing, adjusting indoor air velocity, taking hot/cold drinks, etc., as well as psychological adaptation, has played a role in adapting to the thermal environment. (author)

  17. OPTIMIZATION OF SESAME SEEDS OIL EXTRACTION OPERATING CONDITIONS USING THE RESPONSE SURFACE DESIGN METHODOLOGY

    Directory of Open Access Journals (Sweden)

    HAITHAM OSMAN

    2016-12-01

    Full Text Available This paper applies Response Surface Design (RSD to model the experimental data obtained from the extraction of sesame seeds oil using n-hexane, chloroform and acetone as solvents under different operating conditions. The results obtained revealed that n-hexane outperformed the extraction obtained using chloroform and acetone. The developed model predicted that n-hexane with a rotational speed of 547 rpm and a contact time between the solvent and seeds of 19.46 hours with solvent: seeds ratio of 4.93, yields the optimum oil extracted of 37.03 %, outperforming chloroform and acetone models that gave prediction for 4.75 and 4.21 respectively. While the maximum predictions yield for chloroform is 6.73 %, under the operating conditions of 602 rpm, and 24 hours contact time, with a ratio of solvent: seeds of 1.74. On the other hand the acetone maximum prediction is only 4.37 %, with operational conditions of 467 rpm, and 6.00 hours contact time, with a ratio of solvent: seeds of 1. It is has been found that the maximum oil extraction yield obtained from the chloroform (6.73 % and Acetone (4.37 % is much lower than that predicted by n-hexane 37.03 %.

  18. Biomechanical balance response during induced falls under dual task conditions in people with knee osteoarthritis.

    Science.gov (United States)

    Levinger, Pazit; Nagano, Hanatsu; Downie, Calum; Hayes, Alan; Sanders, Kerrie M; Cicuttini, Flavia; Begg, Rezaul

    2016-07-01

    People with knee osteoarthritis (OA) are at twice the risk of falling compared to older people without knee OA, however the mechanism for this is poorly understood. This study investigated the biomechanical response of the trunk and lower limb joints during a forward induced fall under different task conditions in people with and without knee OA. Twenty-four participants with OA (68.6±6.2 years) and 15 asymptomatic controls (72.4±4.8 years) participated in the study. Forward fall was induced by releasing participants from a static forward leaning position. Participants were required to recover balance during three conditions: normal, physical (obstacle clearance) and cognitive dual tasks (counting backwards). Spatiotemporal parameters, lower limb joint kinematics and kinetics of the recovery limb were compared between the two groups and across the three task conditions. The OA group demonstrated slower spatio-temporal characteristics and reduced hip and knee flexion angles, joint moments/powers and reduced muscle negative work at the knee and ankle (pfall, participants with OA demonstrated difficulty in absorbing the impact and slowing down the forward momentum of the body during a recovery step. Moreover, poor dynamic postural control was demonstrated as task complexity increased. Copyright © 2016 Elsevier B.V. All rights reserved.

  19. Calling phenology of a diverse amphibian assemblage in response to meteorological conditions

    Science.gov (United States)

    Plenderleith, T. Lynette; Stratford, Danial; Lollback, Gregory W.; Chapple, David G.; Reina, Richard D.; Hero, Jean-Marc

    2017-12-01

    The strong association between amphibian activity, breeding and recruitment with local environmental conditions raises concerns regarding how changes in climate may affect the persistence of species populations into the future. Additionally, in a highly diverse assemblage of anurans, competition for breeding sites affects the time and duration of activity, as species compete for limited resources such as water. Meteorological conditions are strong drivers of amphibian activity, so we assessed whether temperature, rainfall, atmospheric pressure and humidity were associated with the calling phenology of an assemblage of anurans in South East Queensland, Australia. We performed calling surveys and collected digital recordings at 45 ponds in an area known for high anuran diversity. We performed detection analyses to investigate the influence of 10 meteorological variables in detection of calling activity in 19 amphibian species. Our results suggest four breeding strategies in the assemblage: explosive summer breeders, prolonged breeders, opportunistic breeders and a winter breeder. Classifying these species into associations provides a framework for understanding how species respond to environmental conditions. Explosive breeders (i.e. species demonstrating short and highly synchronised breeding periods) were particularly responsive to temperature. Our findings help elucidate the breeding phenology of frogs and provide valuable information on their mating systems in native Australian forests. This study highlights the difficulties of surveying even common anurans. We highlight the importance of predictability and stability in climate and the vulnerability of species for which reproduction appears to require highly specific environmental cues.

  20. Fibroblast and T cells conditioned media induce maturation dendritic cell and promote T helper immune response

    Directory of Open Access Journals (Sweden)

    Masoumeh Asadi

    2012-06-01

    Full Text Available Dendritic cells (DCs induce pathogen-specific T cell responses. We comprehensively studied the effects of addition of maturation stimulus, fibroblasts (fibroblast conditioned medium, PHA activated T cells (T cell conditioned medium, and mixture of fibroblast & PHA activated T cells (FCM-TCCM conditioned media on maturation of DCs. Monocytes were cultured with GM-CSF and IL-4 for five days. Maturation factors included MCM and TNF-α as control group. FCM and TCCM, or FCM-TCCM supernatant were considered as the treatment group. Tumor antigens were added at day five. Matured DCs were harvested at day seven. Phenotypic and functional analyses were carried out using anti (CD14, CD80, CD86, CD83 and HLA-DR monoclonal antibodies. Phagocytic activity, mixed lymphocyte reaction (MLR and cytokine production were also evaluated. At the end of culturing period, significantly fully matured DCs with large amount cytoplasm and copious dendritic projections were found in the presence of MCM, TNF-α with or without FCM, TCCM, FCM as well as TCCM. Flow cytometric analysis revealed that expression of CD14 decreased in particular in treated DCs, at the 5th day and expression of CD80, CD86 and HLA-DR was higher when FCM, TCCM, FCM plus TCCM were added to maturation factor. This study demonstrated that DCs matured with these methods had optimum function in comparison with either factor alone.

  1. Responses of Soybean Mutant Lines to Aluminium under In Vitro and In Vivo Condition

    International Nuclear Information System (INIS)

    Yuliasti; Sudarsono

    2011-01-01

    The main limited factors of soybean plants expansion in acid soil are Aluminium (Al) toxicity and low pH. The best approach to solve this problem is by using Al tolerance variety. In vitro or in vivo selections using selective media containing AlCl 3 and induced callus embryonic of mutant lines are reliable methods to develop a new variety. The objectives of this research are to evaluate response of soybean genotypes against AlCl 3 under in vitro and in vivo condition. Addition of 15 part per million (ppm) AlCl 3 into in vitro and in vivo media severely affected plant growth. G3 soybean mutant line was identified as more tolerant than the control soybean cultivar Tanggamus. This mutant line was able to survive under more severe AlCl 3 concentrations (15 ppm) under in vitro conditions. Under in vivo conditions, G1 and G4 mutants were also identified as more tolerant than Tanggamus since they produced more pods and higher dry seed weigh per plant. Moreover, G4 mutant line also produced more dry seed weight per plant than Tanggamus when they were grown on soil containing high Al concentration 8.1 me/100 gr = 81 ppm Al +3 . (author)

  2. Calling phenology of a diverse amphibian assemblage in response to meteorological conditions

    Science.gov (United States)

    Plenderleith, T. Lynette; Stratford, Danial; Lollback, Gregory W.; Chapple, David G.; Reina, Richard D.; Hero, Jean-Marc

    2018-05-01

    The strong association between amphibian activity, breeding and recruitment with local environmental conditions raises concerns regarding how changes in climate may affect the persistence of species populations into the future. Additionally, in a highly diverse assemblage of anurans, competition for breeding sites affects the time and duration of activity, as species compete for limited resources such as water. Meteorological conditions are strong drivers of amphibian activity, so we assessed whether temperature, rainfall, atmospheric pressure and humidity were associated with the calling phenology of an assemblage of anurans in South East Queensland, Australia. We performed calling surveys and collected digital recordings at 45 ponds in an area known for high anuran diversity. We performed detection analyses to investigate the influence of 10 meteorological variables in detection of calling activity in 19 amphibian species. Our results suggest four breeding strategies in the assemblage: explosive summer breeders, prolonged breeders, opportunistic breeders and a winter breeder. Classifying these species into associations provides a framework for understanding how species respond to environmental conditions. Explosive breeders (i.e. species demonstrating short and highly synchronised breeding periods) were particularly responsive to temperature. Our findings help elucidate the breeding phenology of frogs and provide valuable information on their mating systems in native Australian forests. This study highlights the difficulties of surveying even common anurans. We highlight the importance of predictability and stability in climate and the vulnerability of species for which reproduction appears to require highly specific environmental cues.

  3. Role of microRNAs involved in plant response to nitrogen and phosphorous limiting conditions.

    Science.gov (United States)

    Nguyen, Giao N; Rothstein, Steven J; Spangenberg, German; Kant, Surya

    2015-01-01

    Plant microRNAs (miRNAs) are a class of small non-coding RNAs which target and regulate the expression of genes involved in several growth, development, and metabolism processes. Recent researches have shown involvement of miRNAs in the regulation of uptake and utilization of nitrogen (N) and phosphorus (P) and more importantly for plant adaptation to N and P limitation conditions by modifications in plant growth, phenology, and architecture and production of secondary metabolites. Developing strategies that allow for the higher efficiency of using both N and P fertilizers in crop production is important for economic and environmental benefits. Improved crop varieties with better adaptation to N and P limiting conditions could be a key approach to achieve this effectively. Furthermore, understanding on the interactions between N and P uptake and use and their regulation is important for the maintenance of nutrient homeostasis in plants. This review describes the possible functions of different miRNAs and their cross-talk relevant to the plant adaptive responses to N and P limiting conditions. In addition, a comprehensive understanding of these processes at molecular level and importance of biological adaptation for improved N and P use efficiency is discussed.

  4. Unfolded protein response is required for Aspergillus oryzae growth under conditions inducing secretory hydrolytic enzyme production.

    Science.gov (United States)

    Tanaka, Mizuki; Shintani, Takahiro; Gomi, Katsuya

    2015-12-01

    Unfolded protein response (UPR) is an intracellular signaling pathway for adaptation to endoplasmic reticulum (ER) stress. In yeast UPR, Ire1 cleaves the unconventional intron of HAC1 mRNA, and the functional Hac1 protein translated from the spliced HAC1 mRNA induces the expression of ER chaperone genes and ER-associated degradation genes for the refolding or degradation of unfolded proteins. In this study, we constructed an ireA (IRE1 ortholog) conditionally expressing strain of Aspergillus oryzae, a filamentous fungus producing a large amount of amylolytic enzymes, and examined the contribution of UPR to ER stress adaptation under physiological conditions. Repression of ireA completely blocked A. oryzae growth under conditions inducing the production of hydrolytic enzymes, such as amylases and proteases. This growth defect was restored by the introduction of unconventional intronless hacA (hacA-i). Furthermore, UPR was observed to be induced by amylolytic gene expression, and the disruption of the transcriptional activator for amylolytic genes resulted in partial growth restoration of the ireA-repressing strain. In addition, a homokaryotic ireA disruption mutant was successfully generated using the strain harboring hacA-i as a parental host. These results indicated that UPR is required for A. oryzae growth to alleviate ER stress induced by excessive production of hydrolytic enzymes. Copyright © 2015 Elsevier Inc. All rights reserved.

  5. Age- and Wavelength-Dependency of Drosophila Larval Phototaxis and Behavioral Responses to Natural Lighting Conditions

    Directory of Open Access Journals (Sweden)

    Simon G. Sprecher

    2017-04-01

    Full Text Available Animals use various environmental cues as key determinant for their behavioral decisions. Visual systems are hereby responsible to translate light-dependent stimuli into neuronal encoded information. Even though the larval eyes of the fruit fly Drosophila melanogaster are comparably simple, they comprise two types of photoreceptor neurons (PRs, defined by different Rhodopsin genes expressed. Recent findings support that for light avoidance Rhodopsin5 (Rh5 expressing photoreceptors are crucial, while Rhodopsin6 (Rh6 expressing photoreceptors are dispensable under laboratory conditions. However, it remains debated how animals change light preference during larval live. We show that larval negative phototaxis is age-independent as it persists in larvae from foraging to wandering developmental stages. Moreover, if spectrally different Rhodopsins are employed for the detection of different wavelength of light remains unexplored. We found that negative phototaxis can be elicit by light with wavelengths ranging from ultraviolet (UV to green. This behavior is uniquely mediated by Rh5 expressing photoreceptors, and therefore suggest that this photoreceptor-type is able to perceive UV up to green light. In contrast to laboratory our field experiments revealed that Drosophila larvae uses both types of photoreceptors under natural lighting conditions. All our results, demonstrate that Drosophila larval eyes mediate avoidance of light stimuli with a wide, ecological relevant range of quantity (intensities and quality (wavelengths. Thus, the two photoreceptor-types appear more likely to play a role in different aspects of phototaxis under natural lighting conditions, rather than color discrimination.

  6. On the quantification of SSVEP frequency responses in human EEG in realistic BCI conditions.

    Directory of Open Access Journals (Sweden)

    Rafał Kuś

    Full Text Available This article concerns one of the most important problems of brain-computer interfaces (BCI based on Steady State Visual Evoked Potentials (SSVEP, that is the selection of the a-priori most suitable frequencies for stimulation. Previous works related to this problem were done either with measuring systems that have little in common with actual BCI systems (e.g., single flashing LED or were presented on a small number of subjects, or the tested frequency range did not cover a broad spectrum. Their results indicate a strong SSVEP response around 10 Hz, in the range 13-25 Hz, and at high frequencies in the band of 40-60 Hz. In the case of BCI interfaces, stimulation with frequencies from various ranges are used. The frequencies are often adapted for each user separately. The selection of these frequencies, however, was not yet justified in quantitative group-level study with proper statistical account for inter-subject variability. The aim of this study is to determine the SSVEP response curve, that is, the magnitude of the evoked signal as a function of frequency. The SSVEP response was induced in conditions as close as possible to the actual BCI system, using a wide range of frequencies (5-30 Hz, in step of 1 Hz. The data were obtained for 10 subjects. SSVEP curves for individual subjects and the population curve was determined. Statistical analysis were conducted both on the level of individual subjects and for the group. The main result of the study is the identification of the optimal range of frequencies, which is 12-18 Hz, for the registration of SSVEP phenomena. The applied criterion of optimality was: to find the largest contiguous range of frequencies yielding the strong and constant-level SSVEP response.

  7. Post-error action control is neurobehaviorally modulated under conditions of constant speeded response

    Directory of Open Access Journals (Sweden)

    Takahiro eSoshi

    2015-01-01

    Full Text Available Post-error slowing is an error recovery strategy that contributes to action control, and occurs after errors in order to prevent future behavioral flaws. Error recovery often malfunctions in clinical populations, but the relationship between behavioral traits and recovery from error is unclear in healthy populations. The present study investigated the relationship between impulsivity and error recovery by simulating a speeded response situation using a Go/No-go paradigm that forced the participants to constantly make accelerated responses prior to stimuli disappearance (stimulus duration: 250 ms. Neural correlates of post-error processing were examined using event-related potentials (ERPs. Impulsivity traits were measured with self-report questionnaires (BIS-11, BIS/BAS. Behavioral results demonstrated that the commission error for No-go trials was 15%, but post-error slowing did not take place immediately. Delayed post-error slowing was negatively correlated with error rates and impulsivity traits, showing that response slowing was associated with reduced error rates and changed with impulsivity. Response-locked error ERPs were clearly observed for the error trials. Contrary to previous studies, error ERPs were not significantly related to post-error slowing. Stimulus-locked N2 was negatively correlated with post-error slowing and positively correlated with impulsivity traits at the second post-error Go trial: larger N2 activity was associated with greater post-error slowing and less impulsivity. In summary, under constant speeded conditions, error monitoring was dissociated from post-error action control, and post-error slowing did not occur quickly. Furthermore, post-error slowing and its neural correlate (N2 were modulated by impulsivity traits. These findings suggest that there may be clinical and practical efficacy of maintaining cognitive control of actions during error recovery under common daily environments that frequently evoke

  8. Post-error action control is neurobehaviorally modulated under conditions of constant speeded response.

    Science.gov (United States)

    Soshi, Takahiro; Ando, Kumiko; Noda, Takamasa; Nakazawa, Kanako; Tsumura, Hideki; Okada, Takayuki

    2014-01-01

    Post-error slowing (PES) is an error recovery strategy that contributes to action control, and occurs after errors in order to prevent future behavioral flaws. Error recovery often malfunctions in clinical populations, but the relationship between behavioral traits and recovery from error is unclear in healthy populations. The present study investigated the relationship between impulsivity and error recovery by simulating a speeded response situation using a Go/No-go paradigm that forced the participants to constantly make accelerated responses prior to stimuli disappearance (stimulus duration: 250 ms). Neural correlates of post-error processing were examined using event-related potentials (ERPs). Impulsivity traits were measured with self-report questionnaires (BIS-11, BIS/BAS). Behavioral results demonstrated that the commission error for No-go trials was 15%, but PES did not take place immediately. Delayed PES was negatively correlated with error rates and impulsivity traits, showing that response slowing was associated with reduced error rates and changed with impulsivity. Response-locked error ERPs were clearly observed for the error trials. Contrary to previous studies, error ERPs were not significantly related to PES. Stimulus-locked N2 was negatively correlated with PES and positively correlated with impulsivity traits at the second post-error Go trial: larger N2 activity was associated with greater PES and less impulsivity. In summary, under constant speeded conditions, error monitoring was dissociated from post-error action control, and PES did not occur quickly. Furthermore, PES and its neural correlate (N2) were modulated by impulsivity traits. These findings suggest that there may be clinical and practical efficacy of maintaining cognitive control of actions during error recovery under common daily environments that frequently evoke impulsive behaviors.

  9. Social responsibility and work conditions: building a reference label, Démarche T®.

    Science.gov (United States)

    Biquand, Sylvain; Zittel, Benoit

    2012-01-01

    Corporate Social Responsibility (CSR) is now considered in large and global companies and the recent publication of the ISO 26000 standard clarifies the targets. Based on our consultancy's experience for fifteen years in ergonomics mainly in French small and medium enterprises, we developed a label to coax and value efforts of companies in dealing with health and safety at the work place as required by ISO 26000 paragraph 6.4. The formal approach of ISO describes what should be achieved but gives no cue on how actual conditions of work should be improved. The label, called Démarche T (ie Process W where W stands for work) aims the management of work conditions as a process, giving visibility and credit to companies for their continuous involvement in the matter. We describe the items and processes that are part of our assessment. We first conduct an ergonomic diagnosis including the analysis of records on health, physical and psychological well-being, observations at the workplace and interviews with the workers. This diagnosis is followed by recommendations. The fulfillment of these is assessed yearly. Items under assessment include: - ergonomics, health and safety in the companies statements and their impact in actual project management; - relations with workers through the committee for health and safety; - actual results on health, safety and work conditions. On a local level, we give the companies passing the label a competitive edge in recruiting better candidates motivated by good work conditions, and help them fulfill ISO 26000 requirements, an increasingly decisive advantage to benefit from public regional and European support. Our paper describes the diagnosis and follow-up process.

  10. Thyroid transcriptome analysis reveals different adaptive responses to cold environmental conditions between two chicken breeds.

    Science.gov (United States)

    Xie, Shanshan; Yang, Xukai; Wang, Dehe; Zhu, Feng; Yang, Ning; Hou, Zhuocheng; Ning, Zhonghua

    2018-01-01

    Selection for cold tolerance in chickens is important for improving production performance and animal welfare. The identification of chicken breeds with higher cold tolerance and production performance will help to target candidates for the selection. The thyroid gland plays important roles in thermal adaptation, and its function is influenced by breed differences and transcriptional plasticity, both of which remain largely unknown in the chicken thyroid transcriptome. In this study, we subjected Bashang Long-tail (BS) and Rhode Island Red (RIR) chickens to either cold or warm environments for 21 weeks and investigated egg production performance, body weight changes, serum thyroid hormone concentrations, and thyroid gland transcriptome profiles. RIR chickens had higher egg production than BS chickens under warm conditions, but BS chickens produced more eggs than RIRs under cold conditions. Furthermore, BS chickens showed stable body weight gain under cold conditions while RIRs did not. These results suggested that BS breed is a preferable candidate for cold-tolerance selection and that the cold adaptability of RIRs should be improved in the future. BS chickens had higher serum thyroid hormone concentrations than RIRs under both environments. RNA-Seq generated 344.3 million paired-end reads from 16 sequencing libraries, and about 90% of the processed reads were concordantly mapped to the chicken reference genome. Differential expression analysis identified 46-1,211 genes in the respective comparisons. With regard to breed differences in the thyroid transcriptome, BS chickens showed higher cell replication and development, and immune response-related activity, while RIR chickens showed higher carbohydrate and protein metabolism activity. The cold environment reduced breed differences in the thyroid transcriptome compared with the warm environment. Transcriptional plasticity analysis revealed different adaptive responses in BS and RIR chickens to cope with the cold

  11. A comparison of cytokine responses during prolonged cycling in normal and hot environmental conditions

    Directory of Open Access Journals (Sweden)

    Ludmila M Cosio-Lima

    2011-01-01

    Full Text Available Ludmila M Cosio-Lima, Bhargav V Desai, Petra B Schuler, Lesley Keck, Logan ScheelerDepartment of Health, Leisure, and Exercise Science, University of West Florida, Pensacola, FL, USAPurpose: Components of immune function are affected by physical activity in an adverse environment. The purpose of this study was to compare plasma differences in inflammatory cytokines including tumor necrosis factor α (TNF-α and interleukin 6 (IL-6, in addition to the stress hormone cortisol, during prolonged cycling under normal and hot environmental conditions in elite cyclists.Methods and design: Six trained elite male cyclists (27 ± 8 years; 75.5 ± 4 kg; maximum oxygen uptake [VO2max] = 66 ± 6 mL/kg/min, mean ± SD. The cyclists biked for 2.5 h at their prescribed 60% maximum exercise workload (Wmax or 75% VO2max either in an environmental chamber set at 15°C and 40% relative humidity (NEUTRAL or at 35°C and 40% relative humidity (HOT. The cyclists were given 4 mL of water/kg body weight every 15 min under both conditions.Results: Total cortisol concentrations were elevated (P < 0.05 immediately postexercise and 12 h postexercise in both the NEUTRAL and HOT conditions. TNF-α concentrations were only significantly (P = 0.045 elevated postexercise in HOT conditions. During the HOT conditions, a significant (P = 0.006 and 0.007, respectively difference in IL-6 was seen immediately after and 12 h postexercise. During the NEUTRAL condition, IL-6 was only significantly elevated postexercise (P < 0.05.Conclusions: Heat exposure during a long bout of exercise is sufficient to elicit stress response in elite cyclists. However, the degree of release of anti-inflammatory and proinflammatory cytokines might be related to several factors that include the athlete’s fitness level, hydration status, exercise intensity, and length of exposure to hot environments.Keywords: cytokines, inflammation, heat, exercise, performance 

  12. Physiological responses to variations in grazing and light conditions in native and invasive fucoids.

    Science.gov (United States)

    Olabarria, Celia; Arenas, Francisco; Fernández, Ángela; Troncoso, Jesús S; Martínez, Brezo

    2018-08-01

    Poor physiological acclimatization to climate change has led to shifts in the distributional ranges of various species and to biodiversity loss. However, evidence also suggests the relevance of non-climatic physical factors, such as light, and biotic factors, which may act in interactive or additive way. We used a mechanistic approach to evaluate the ecophysiological responses of four seaweed species (three dominant intertidal fucoids, Fucus serratus, Ascophyllum nodosum, Bifurcaria bifurcata, and the invasive Sargassum muticum) to different conditions of grazing, light irradiance and ultraviolet (UV) radiation. We performed a large-scale mesocosm experiment with a total of 800 individual thalli of macroalgae. The factorial experimental design included major algal traits, photoacclimation, nutrient stoichiometry and chemical defence as response variables. Few significant effects of the factors acting alone or in combination were observed, suggesting a good capacity for acclimatization in all four species. The significant effects were generally additive and there were no potentially deleterious synergistic effects between factors. Fucus serratus, a species currently undergoing a drastic contraction of its southern distribution limit in Europe, was the most strongly affected species, showing overall lower photosynthetic efficiency than the other species. The growth rate of F. serratus decreased when UV radiation was filtered out, but only in the presence of grazers. Moreover, more individuals of this species tended to reach maturity in the absence of grazers, and the nitrogen content of tissues decreased under full-spectrum light. Only the phlorotannin content of tissues of B. bifurcata and of exudates of A. nodosum, both slow-growing species, were positively affected by respectively removal of UVB radiation and the presence of grazers. The findings for S. muticum, a well-established invasive seaweed across European coasts, suggested similar physiological response of

  13. Tissue responses to fractional transient heating with sinusoidal heat flux condition on skin surface.

    Science.gov (United States)

    Ezzat, Magdy A; El-Bary, Alaa A; Al-Sowayan, Noorah S

    2016-10-01

    A fractional model of Bioheat equation for describing quantitatively the thermal responses of skin tissue under sinusoidal heat flux conditions on skin surface is given. Laplace transform technique is used to obtain the solution in a closed form. The resulting formulation is applied to one-dimensional application to investigate the temperature distribution in skin with instantaneous surface heating for different cases. According to the numerical results and its graphs, conclusion about the fractional bioheat transfer equation has been constructed. Sensitivity analysis is performed to explore the thermal effects of various control parameters on tissue temperature. The comparisons are made with the results obtained in the case of the absence of time-fractional order. © 2016 Japanese Society of Animal Science. © 2016 Japanese Society of Animal Science.

  14. Thermoluminescence response of calcic bentonite subjected to conditions of high nuclear waste underground storage

    International Nuclear Information System (INIS)

    Dies, J.; Miralles, L.; Tarrasa, F.; Pueyo, J.J.; Cuevas, C. de las

    2002-01-01

    Bentonite is regarded as a backfilling material for underground storage facilities of highly radioactive nuclear waste built on granite formations. In these facilities, bentonite will be subjected to a gradient of temperature and dose rate, achieving a very high integrated dose and, therefore, changes in its structure and physical properties may take place. Two experiments to discriminate between the thermal and the irradiation effect were performed. In the first (named BIC-2A), samples were subjected to temperature while in second (named BIC-2B) the combined effect of temperature and irradiation was studied. The experimental conditions were: a thermal gradient between 130 deg. C and 90 deg. C, a maximum dose rate of 3.5 kGy.h -1 and a gradient of the integrated dose between 1.75 MGy and 10 MGy. Both experiments lasted a total of 124 days. An irradiation source of 60 Co with an activity close to 300,000 Ci, and bentonite samples of 200 mm in length and 50 mm in diameter were used. After the experiment, the samples were ground and two fractions were obtained: a fine fraction ( 80 μm). The results are described of thermoluminescence analyses on the two fractions obtained which showed that the coarse fractions can be 100 times more sensitive to radiation than the fine fraction. On the other hand, the heated and irradiated samples showed a thermoluminescence response around 50 times greater than the samples that were only heated. In addition to this, the temperature and dose rate conditions are relevant parameters in the generation and stabilisation of radiation induced defects. Finally, the response of samples heated and irradiated for two months was quite similar to that obtained on samples heated and irradiated for four months, indicating a saturation phenomenon. (author)

  15. Physical Responses of Convective Heavy Rainfall to Future Warming Condition: Case Study of the Hiroshima Event

    Directory of Open Access Journals (Sweden)

    Kenshi Hibino

    2018-04-01

    Full Text Available An extreme precipitation event happened at Hiroshima in 2014. Over 200 mm of total rainfall was observed on the night of August 19th, which caused floods and many landslides. The rainfall event was estimated to be a rare event happening once in approximately 30 years. The physical response of this event to the change of the future atmospheric condition, which includes a temperature increase on average and convective stability change, is investigated in the present study using a 27-member ensemble experiment and pseudo global warming downscaling method. The experiment is integrated using the Japan Meteorological Research Institute non-hydrostatic regional climate model. A very high-resolution horizontal grid, 500 m, is used to reproduce dense cumulonimbus cloud formation causing heavy rainfall in the model. The future climate condition determined by a higher greenhouse gas concentration is prescribed to the model, in which the surface air temperature globally averaged is 4 K warmer than that in the preindustrial era. The total amounts of precipitation around the Hiroshima area in the future experiments are closer to or slightly lower than in the current experiments in spite of the increase in water vapor due to the atmospheric warming. The effect of the water vapor increase on extreme precipitation is found to be canceled out by the suppression of convection due to the thermal stability enhancement. The fact that future extreme precipitation like the Hiroshima event is not intensified is in contrast to the well-known result that extreme rainfall tends to be intensified in the future. The results in the present study imply that the response of extreme precipitation to global warming differs for each rainfall phenomenon.

  16. Experimental investigation of a forced response condition in a multistage compressor

    Science.gov (United States)

    Murray, William Louis, III

    The objective of this research is twofold. Firstly, the design, development, and construction of a test facility for a Honeywell APU-style centrifugal compressor was implemented, as well as the design and construction of an inlet flow experiment. Secondly, the aeromechanical response of an embedded stage in the Purdue 3-Stage axial research compressor was analyzed through a suite of different measurement techniques in the fulfillment of the end of the GUIde IV Consortium contract. The purpose of the first phase of Honeywell work was to comprehensively measure the flow field of an APU-style centrifugal compressor inlet through the use of Laser Doppler Velocimetry (LDV). A portion of a Honeywell supplied inlet was modified to provide optical access to the elbow, and a gas ejector system was designed and constructed to provide the same suction to the inlet that it would see during operation with the compressor. A performance and health monitoring electronics system was designed and purchased to support the testing of the Honeywell inlet ejector system and eventually it will be used for testing with a centrifugal compressor. Additionally, a secondary air and oil system has been designed and is currently being constructed in the test cell in preparation for the arrival of the Honeywell compressor this summer. An embedded rotor stage in the Purdue 3-stage compressor, with a Campbell diagram crossing of the 1T vibratory mode was analyzed with a suite of measurement systems. In addition to steady state compressor performance measurements, other types of measurements were used to characterize the aerodynamic forcing function for this forced response condition including: NSMS, high-frequency pressure transducers mounted in the casing and in a downstream stator, and cross-film thermal anemometry. Rotor geometry was measured by Aerodyne using an in-situ laser scanning technique. Vibrometry testing was performed at WPAFB to characterize safe operating speeds for stator

  17. Numerical experiments on the atmospheric response to cold Equatorial Pacific conditions ('La Nina') during northern summer

    International Nuclear Information System (INIS)

    Storch, H. von; Schriever, D.; Arpe, K.; Branstator, G.W.; Legnani, R.; Ulbrich, U.

    1993-01-01

    The effect of cold conditions in the central and eastern Equatorial Pacific during Northern Summer is examined in a series of numerical experiments with the low resolution (T21) atmospheric general circulation model ECHAM2. Anomalous sea surface temperatures (SST) as observed in June 1988 were prescribed and the effect on the global circulation is examined. In the model atmosphere, the anomalous cold water in the Equatorial Pacific excites a strong and stable response over the tropical Central and East Pacific. From here stationary Rossby waves radiate into both hemispheres. The Northern Hemisphere wave train is weak and affects only the Northeast Pacific area; the Southern Hemisphere wave train arches from the Central Pacific over the southern tip of South America to the South Atlantic. This response is not only present in the basic anomaly experiment with the T21 GCM but also in experiments with SST anomalies confined to the tropics and with an envelope-formulation of the SST anomalies, in experiments with a linear model, and in high resolution (T42) model experiments. The model output is also compared to the actually observed atmospheric state in June 1988. (orig./KW)

  18. Response of cotton genotypes to boron under-b-adequate conditions

    International Nuclear Information System (INIS)

    Shah, J. A.; Sial, M. A.; Hassan, Z. U.; Rajpar, I.

    2015-01-01

    Balanced boron (B) application is well-known to enhance the cotton production; however, the narrow range between B-deficiency and toxicity levels makes it difficult to manage. Cotton genotypes extensively differ in their response to B requirements. The adequate dose of B for one genotype may be insufficient or even toxic to other genotype. The effects of boron (B) on seed cotton yield and its various yield associated traits were studied on 10 cotton genotypes of Pakistan. The pot studies were undertaken to categorize cotton genotypes using B-deficient (control) and B-adequate (2.0 kg B ha-1) levels arranged in CRD with four repeats. The results indicated that the seed cotton yield, yield attributes and B-uptake of genotypes were comparatively decreased in B-deficient stressed treatment. Genotype NIA-Ufaq exhibited wide range of adaptation and ranked as efficient-responsive, as it produced higher seed cotton yield under both B-regimes. SAU-2 and CIM-506 were highly-efficient and remaining all genotypes were medium-efficient. Genotype Sindh-1 produced low seed cotton yield under B deficient condition and ranked as low-efficient. B-efficient cotton genotypes can be grown in B deficient soils without B application. (author)

  19. Consistency of metabolic responses and appetite sensations under postabsorptive and postprandial conditions.

    Science.gov (United States)

    Gonzalez, Javier T; Veasey, Rachel C; Rumbold, Penny L S; Stevenson, Emma J

    2012-10-01

    The present study aimed to investigate the reliability of metabolic and subjective appetite responses under fasted conditions and following consumption of a cereal-based breakfast. Twelve healthy, physically active males completed two postabsorption (PA) and two postprandial (PP) trials in a randomised order. In PP trials a cereal based breakfast providing 1859 kJ of energy was consumed. Expired gas samples were used to estimate energy expenditure and fat oxidation and 100mm visual analogue scales were used to determine appetite sensations at baseline and every 30 min for 120 min. Reliability was assessed using limits of agreement, coefficient of variation (CV), intraclass coefficient of correlation and 95% confidence limits of typical error. The limits of agreement and typical error were 292.0 and 105.5 kJ for total energy expenditure, 9.3 and 3.4 g for total fat oxidation and 22.9 and 8.3mm for time-averaged AUC for hunger sensations, respectively over the 120 min period in the PP trial. The reliability of energy expenditure and appetite in the 2h response to a cereal-based breakfast would suggest that an intervention requires a 211 kJ and 16.6mm difference in total postprandial energy expenditure and time-averaged hunger AUC to be meaningful, fat oxidation would require a 6.7 g difference which may not be sensitive to most meal manipulations. Copyright © 2012 Elsevier Ltd. All rights reserved.

  20. Metabolic response of Candida albicans to phenylethyl alcohol under hyphae-inducing conditions.

    Science.gov (United States)

    Han, Ting-Li; Tumanov, Sergey; Cannon, Richard D; Villas-Boas, Silas G

    2013-01-01

    Phenylethyl alcohol was one of the first quorum sensing molecules (QSMs) identified in C. albicans. This extracellular signalling molecule inhibits the hyphal formation of C. albicans at high cell density. Little is known, however, about the underlying mechanisms by which this QSM regulates the morphological switches of C. albicans. Therefore, we have applied metabolomics and isotope labelling experiments to investigate the metabolic changes that occur in C. albicans in response to phenylethyl alcohol under defined hyphae-inducing conditions. Our results showed a global upregulation of central carbon metabolism when hyphal development was suppressed by phenylethyl alcohol. By comparing the metabolic changes in response to phenylethyl alcohol to our previous metabolomic studies, we were able to short-list 7 metabolic pathways from central carbon metabolism that appear to be associated with C. albicans morphogenesis. Furthermore, isotope-labelling data showed that phenylethyl alcohol is indeed taken up and catabolised by yeast cells. Isotope-labelled carbon atoms were found in the majority of amino acids as well as in lactate and glyoxylate. However, isotope-labelled carbon atoms from phenylethyl alcohol accumulated mainly in the pyridine ring of NAD(+)/NADH and NADP(-/)NADPH molecules, showing that these nucleotides were the main products of phenylethyl alcohol catabolism. Interestingly, two metabolic pathways where these nucleotides play an important role, nitrogen metabolism and nicotinate/nicotinamide metabolism, were also short-listed through our previous metabolomics works as metabolic pathways likely to be closely associated with C. albicans morphogenesis.

  1. Ballistic Impact Response of Kevlar 49 and Zylon under Conditions Representing Jet Engine Fan Containment

    Science.gov (United States)

    Pereira, J. Michael; Revilock, Duane M.

    2007-01-01

    A ballistic impact test program was conducted to provide validation data for the development of numerical models of blade out events in fabric containment systems. The impact response of two different fiber materials - Kevlar 49 (E.I. DuPont Nemours and Company) and Zylon AS (Toyobo Co., Ltd.) was studied by firing metal projectiles into dry woven fabric specimens using a gas gun. The shape, mass, orientation and velocity of the projectile were varied and recorded. In most cases the tests were designed such that the projectile would perforate the specimen, allowing measurement of the energy absorbed by the fabric. The results for both Zylon and Kevlar presented here represent a useful set of data for the purposes of establishing and validating numerical models for predicting the response of fabrics under conditions simulating those of a jet engine blade release situation. In addition some useful empirical observations were made regarding the effects of projectile orientation and the relative performance of the different materials.

  2. Response of the agile antechinus to habitat edge, configuration and condition in fragmented forest.

    Directory of Open Access Journals (Sweden)

    Christopher P Johnstone

    Full Text Available Habitat fragmentation and degradation seriously threaten native animal communities. We studied the response of a small marsupial, the agile antechinus Antechinus agilis, to several environmental variables in anthropogenically fragmented Eucalyptus forest in south-east Australia. Agile antechinus were captured more in microhabitats dominated by woody debris than in other microhabitats. Relative abundances of both sexes were positively correlated with fragment core area. Male and female mass-size residuals were smaller in larger fragments. A health status indicator, haemoglobin-haematocrit residuals (HHR, did not vary as a function of any environmental variable in females, but male HHR indicated better health where sites' microhabitats were dominated by shrubs, woody debris and trees other than Eucalyptus. Females were trapped less often in edge than interior fragment habitat and their physiological stress level, indicated by the neutrophil/lymphocyte ratio in peripheral blood, was higher where fragments had a greater proportion of edge habitat. The latter trend was potentially due to lymphopoenia resulting from stress hormone-mediated leukocyte trafficking. Using multiple indicators of population condition and health status facilitates a comprehensive examination of the effects of anthropogenic disturbances, such as habitat fragmentation and degradation, on native vertebrates. Male agile antechinus' health responded negatively to habitat degradation, whilst females responded negatively to the proportion of edge habitat. The health and condition indicators used could be employed to identify conservation strategies that would make habitat fragments less stressful for this or similar native, small mammals.

  3. Broad-Scale Environmental Conditions Responsible for Post-Fire Vegetation Dynamics

    Directory of Open Access Journals (Sweden)

    Stuart E. Marsh

    2010-11-01

    Full Text Available Ecosystem response to disturbance is influenced by environmental conditions at a number of scales. Changes in climate have altered fire regimes across the western United States, and have also likely altered spatio-temporal patterns of post-fire vegetation regeneration. Fire occurrence data and a vegetation index (NDVI derived from the NOAA Advanced Very High Resolution Radiometer (AVHRR were used to monitor post-fire vegetation from 1989 to 2007. We first investigated differences in post-fire rates of vegetation regeneration between ecoregions. We then related precipitation, temperature, and elevation records at four temporal scales to rates of post-fire vegetation regeneration to ascertain the influence of climate on post-fire vegetation dynamics. We found that broad-scale climate factors are an important influence on post-fire vegetation regeneration. Most notably, higher rates of post-fire regeneration occurred with warmer minimum temperatures. Increases in precipitation also resulted in higher rates of post-fire vegetation growth. While explanatory power was slight, multiple statistical approaches provided evidence for real ecological drivers of post-fire regeneration that should be investigated further at finer scales. The sensitivity of post-disturbance vegetation dynamics to climatic drivers has important ramifications for the management of ecosystems under changing climatic conditions. Shifts in temperature and precipitation regimes are likely to result in changes in post-disturbance dynamics, which could represent important feedbacks into the global climate system.

  4. Empirical model for the electron density peak height disturbance in response to solar wind conditions

    Science.gov (United States)

    Blanch, E.; Altadill, D.

    2009-04-01

    Geomagnetic storms disturb the quiet behaviour of the ionosphere, its electron density and the electron density peak height, hmF2. Many works have been done to predict the variations of the electron density but few efforts have been dedicated to predict the variations the hmF2 under disturbed helio-geomagnetic conditions. We present the results of the analyses of the F2 layer peak height disturbances occurred during intense geomagnetic storms for one solar cycle. The results systematically show a significant peak height increase about 2 hours after the beginning of the main phase of the geomagnetic storm, independently of both the local time position of the station at the onset of the storm and the intensity of the storm. An additional uplift is observed in the post sunset sector. The duration of the uplift and the height increase are dependent of the intensity of the geomagnetic storm, the season and the local time position of the station at the onset of the storm. An empirical model has been developed to predict the electron density peak height disturbances in response to solar wind conditions and local time which can be used for nowcasting and forecasting the hmF2 disturbances for the middle latitude ionosphere. This being an important output for EURIPOS project operational purposes.

  5. Seismic responses of an unanchored generic fixture with different simulated boundary conditions

    International Nuclear Information System (INIS)

    Wu, T.S.; Blomquist, C.A.; Herceg, J.E.

    1994-01-01

    In the design of equipment for seismic loadings, it is common to anchor the equipment to prevent tipping or sliding. However, there are situations where the equipment should not be anchored. An unanchored piece of equipment is held to the floor only by the gravitational effect and, in the absence of friction, it could move freely. In the analytical investigation of an unanchored item during a seismic event, there is uncertainty on the proper simulation of the boundary conditions so that the analysis model will have no rigid-body motion. Seismic responses of a simple analytical model that is representative of a group of unanchored equipment have been investigated with different sets of simulated boundary conditions. The results show that, when the main interest of investigation is to assess the potential for tipping during an earthquake, the case with one of the four supporting pads simply supported, its two neighboring pads constrained against twisting motion, and all pads without vertical displacements yields the most conservative prediction. The analysis is applied to the fuel processing cell of the Integral Fast Reactor project. In order not to breach the liner of the existing facility and to keep operational flexibility of the fixtures, all new equipment to be installed within the fuel processing cell are required to be unanchored

  6. Numerical study on lithium titanate battery thermal response under adiabatic condition

    International Nuclear Information System (INIS)

    Sun, Qiujuan; Wang, Qingsong; Zhao, Xuejuan; Sun, Jinhua; Lin, Zijing

    2015-01-01

    Highlights: • The thermal behavior of lithium titanate battery during cycling was investigated. • The temperature rate in charging was less than that of discharging in the cycling. • The temperature difference was less than 0.02 °C at 0.5 C in adiabatic condition. • The temperature distribution and thermal runaway of the battery were predicted. - Abstract: To analyze the thermal behavior of 945 mA h lithium titanate battery during charging and discharging processes, the experimental and numerical studies are performed in this work. The cathode and anode of the 945 mA h lithium titanate soft package battery are the lithium nickel–cobalt–manganese-oxide and lithium titanate, respectively. In the experiment, an Accelerating Rate Calorimeter combined with battery cycler is employed to investigate the electrochemical–thermal behavior during charge–discharge cycling under the adiabatic condition. In numerical simulation, one electrochemical-thermal model is adopted to predict the thermal response and validated with the experimental results. From both experimental and simulated results, the profile of potential and current, the heat generation, the temperature, the temperature changing rate and the temperature distribution in the cell are obtained and thermal runaway is predicted. The analysis of the electrochemical and thermal behavior is beneficial for the commercial application of lithium titanate battery in the fields of electric vehicles and hybrid electric vehicles

  7. Response of Nuclear Power Plant Instrumentation Cables Exposed to Fire Conditions.

    Energy Technology Data Exchange (ETDEWEB)

    Muna, Alice Baca [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); LaFleur, Chris Bensdotter [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Brooks, Dusty Marie [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

    2017-09-01

    This report presents the results of instrumentation cable tests sponsored by the US Nuclear Regulatory Commission (NRC) Office of Nuclear Regulatory Research and performed at Sandia National Laboratories (SNL). The goal of the tests was to assess thermal and electrical response behavior under fire-exposure conditions for instrumentation cables and circuits. The test objective was to assess how severe radiant heating conditions surrounding an instrumentation cable affect current or voltage signals in an instrumentation circuit. A total of thirty-nine small-scale tests were conducted. Ten different instrumentation cables were tested, ranging from one conductor to eight-twisted pairs. Because the focus of the tests was thermoset (TS) cables, only two of the ten cables had thermoplastic (TP) insulation and jacket material and the remaining eight cables were one of three different TS insulation and jacket material. Two instrumentation cables from previous cable fire testing were included, one TS and one TP. Three test circuits were used to simulate instrumentation circuits present in nuclear power plants: a 4–20 mA current loop, a 10–50 mA current loop and a 1–5 VDC voltage loop. A regression analysis was conducted to determine key variables affecting signal leakage time.

  8. Modulation of Radiation responses by pre-exposure to irradiated Cell conditioned medium.

    LENUS (Irish Health Repository)

    Maguire, Paula

    2007-04-01

    The aim of this study was to investigate whether exposure of HPV-G cells to irradiated cell conditioned medium (ICCM) could induce an adaptive response if the cells were subsequently challenged with a higher ICCM dose. Clonogenic survival and major steps in the cascade leading to apoptosis, such as calcium influx and loss of mitochondrial membrane potential, were examined to determine whether these events could be modified by giving a priming dose of ICCM before the challenge dose. Clonogenic survival data indicated an ICCM-induced adaptive response in HPV-G cells "primed" with 5 mGy or 0.5 Gy ICCM for 24 h and then exposed to 0.5 Gy or 5 Gy ICCM. Reactive oxygen species (ROS) were found to be involved in the bystander-induced cell death. Calcium fluxes varied in magnitude across the exposed cell population, and a significant number of the primed HPV-G cells did not respond to the challenge ICCM dose. No significant loss of mitochondrial membrane potential was observed when HPV-G cells were exposed to 0.5 Gy ICCM for 24 h followed by exposure to 5 Gy ICCM for 6 h. Exposure of HPV-G cells to 5 mGy ICCM for 24 h followed by exposure to 0.5 Gy ICCM for 18 h caused a significant increase in mitochondrial mass and a change in mitochondrial location, events associated with the perpetuation of genomic instability. This study has shown that a priming dose of ICCM has the ability to induce an adaptive response in HPV-G cells subsequently exposed to a challenge dose of ICCM.

  9. Effects of exercise conditioning on thermoregulatory responses to repeated administration of chlorpyrifos

    International Nuclear Information System (INIS)

    Rowsey, Pamela Johnson; Metzger, Bonnie L.; Arlson, John; Gordon, Christopher J.

    2003-01-01

    little is known about the effects of physical activity (i.e., exercise training) on susceptibility to environmental toxicants. Chloropyrifos (CHP), an organophosphate (OP) insecticide, affects thermoregulation, causing a cute period of hypothermia followed by a delayed fever. Since exercise conditioning alters the thermo regulatory responses of rodents, this study examined whether exercise training would alter the thermo regulatory response to repeated CHP administration in the female Sprague-Dawley rat. Core temperature (T c ) and motor activity (MA) were monitored by radio telemetry in rats housed at an ambient temperature (T a ) of 22 deg. C. The rats either were provided with continuous access to running wheels (exercise group) or were housed in standard cages without wheels (sedentary group). The exercise group rats ran predominately at night with an average of 7.6 km/24 h. After 8 weeks the rats in both groups were garaged daily with corn oil or 10 mg/kg HP (dissolved in corn oil) for 4 days. CHP induced an immediate hypothermic response followed by a delayed fever throughout the next day in the sedentary group rats after the first three doses of CHP. The exercise group rats showed no hypothermia after the first dose of CHP. However, they became hypothermic after the second and third doses of CHP. The exercise group rats developed a smaller daytime fever after each dose of CHP compared to the sedentary group rats. Overall, exercise training attenuated the hypothermic and febrile effects of repeated CHP. Thus, the data suggest that a sedentary lifestyle may increase the sensitivity to OP insecticides. Exercise training was also associated with a more rapid recovery of plasma cholinesterase activity

  10. Physiological response of Crocosphaera watsonii to enhanced and fluctuating carbon dioxide conditions.

    Directory of Open Access Journals (Sweden)

    Mary R Gradoville

    Full Text Available We investigated the effects of elevated pCO2 on cultures of the unicellular N2-fixing cyanobacterium Crocosphaera watsonii WH8501. Using CO2-enriched air, cultures grown in batch mode under high light intensity were exposed to initial conditions approximating current atmospheric CO2 concentrations (∼ 400 ppm as well as CO2 levels corresponding to low- and high-end predictions for the year 2100 (∼ 750 and 1000 ppm. Following acclimation to CO2 levels, the concentrations of particulate carbon (PC, particulate nitrogen (PN, and cells were measured over the diurnal cycle for a six-day period spanning exponential and early stationary growth phases. High rates of photosynthesis and respiration resulted in biologically induced pCO2 fluctuations in all treatments. Despite this observed pCO2 variability, and consistent with previous experiments conducted under stable pCO2 conditions, we observed that elevated mean pCO2 enhanced rates of PC production, PN production, and growth. During exponential growth phase, rates of PC and PN production increased by ∼ 1.2- and ∼ 1.5-fold in the mid- and high-CO2 treatments, respectively, when compared to the low-CO2 treatment. Elevated pCO2 also enhanced PC and PN production rates during early stationary growth phase. In all treatments, PC and PN cellular content displayed a strong diurnal rhythm, with particulate C:N molar ratios reaching a high of 22:1 in the light and a low of 5.5:1 in the dark. The pCO2 enhancement of metabolic rates persisted despite pCO2 variability, suggesting a consistent positive response of Crocosphaera to elevated and fluctuating pCO2 conditions.

  11. Optimization of Coolant Technique Conditions for Machining A319 Aluminium Alloy Using Response Surface Method (RSM)

    Science.gov (United States)

    Zainal Ariffin, S.; Razlan, A.; Ali, M. Mohd; Efendee, A. M.; Rahman, M. M.

    2018-03-01

    Background/Objectives: The paper discusses about the optimum cutting parameters with coolant techniques condition (1.0 mm nozzle orifice, wet and dry) to optimize surface roughness, temperature and tool wear in the machining process based on the selected setting parameters. The selected cutting parameters for this study were the cutting speed, feed rate, depth of cut and coolant techniques condition. Methods/Statistical Analysis Experiments were conducted and investigated based on Design of Experiment (DOE) with Response Surface Method. The research of the aggressive machining process on aluminum alloy (A319) for automotive applications is an effort to understand the machining concept, which widely used in a variety of manufacturing industries especially in the automotive industry. Findings: The results show that the dominant failure mode is the surface roughness, temperature and tool wear when using 1.0 mm nozzle orifice, increases during machining and also can be alternative minimize built up edge of the A319. The exploration for surface roughness, productivity and the optimization of cutting speed in the technical and commercial aspects of the manufacturing processes of A319 are discussed in automotive components industries for further work Applications/Improvements: The research result also beneficial in minimizing the costs incurred and improving productivity of manufacturing firms. According to the mathematical model and equations, generated by CCD based RSM, experiments were performed and cutting coolant condition technique using size nozzle can reduces tool wear, surface roughness and temperature was obtained. Results have been analyzed and optimization has been carried out for selecting cutting parameters, shows that the effectiveness and efficiency of the system can be identified and helps to solve potential problems.

  12. Economic potential of demand response at household level—Are Central-European market conditions sufficient?

    International Nuclear Information System (INIS)

    Prüggler, Natalie

    2013-01-01

    The aim of this paper is to show the economic potential of demand response (DR) on household level at Central European market conditions. Thereby, required economic benefits for consumers' participation, the realistic load shifting potential at household level and the estimation of essential intelligent infrastructure costs are discussed. The core of this paper builds a case-study applying spot market-oriented load shifting from the supplier's point of view by using Austrian electricity market data, household load profiles as well as a heat pump and e-car charging load profile. It is demonstrated which cost savings for suppliers can be derived from such load shifting procedure at household level. Furthermore, upper cost limits for intelligent infrastructure in order to break-even are derived. Results suggest to take a critical look at European discussions on DR implementation on household level, showing that at Central European market conditions the potential for DR at household level is restricted to significant loads and hence, the applied load shifting strategy is only beneficial with application to heat pumps. In contrast, the frequently discussed shifting of conventional household devices' loads (such as washing machines) economically does not add up. - Highlights: • Calculation of economic potential of domestic DR at Central European market conditions. • Model and case-study of spot market-oriented load shifting from supplier's perspective. • Derivation of supplier's cost savings and upper cost limits for ICT infrastructure. • Results show economic potential of domestic DR to be restricted to significant loads. • Shifting of washing machines economically does not pay off in contrast to heat pumps

  13. Wild trout responses to a stress experience following confinement conditions during the spawning season

    Directory of Open Access Journals (Sweden)

    Gilberto Forneris

    2010-01-01

    Full Text Available Salmo (trutta marmoratus is an endemic specie in the North of Italy, subjected to hybridization with domesticated strains of trout. Native populations are managed by supportive release in the rivers. Wild breeders are captured, confined in facility for short periods and then released in the river after artificial fertilization. Premature mortality during confinement and post release mortality in river have been observed in breeders supporting the view that confinement stress could be the cause. Twenty-six adult individuals of trout were captured from a river by electrofishing and stocked in two tanks, the first one (RF provided with artificial refuges to simulate the natural environment and covered by dark panels; the second tank (TR was only partially covered by dark panels and without artificial refuges. All the other conditions were identical and animals were fed ad libitum with natural food collected in the same river. After 50 days, from a third group of 8 trout (WD captured in the same river by a 5 minute electrofishing session, blood samples were sequentially collected for the assessment of serum cortisol response to serial repeated handlings. With the same sequential method, individuals of the RF and TR experimental groups were sampled. Cortisol levels were compared between groups by ANOVA. Biomass densities decreased during the experiment due to premature mortality of the largest individuals in both the RF (7.69% and TR (30.77% groups. At the end of the experiment, data clearly demonstrated that after a stressing confinement, the TR group shown a reduced poststress response to the successive serial handlings. Vice versa the group RF, that experienced a more careful confinement, responded to the second serial acute stressing manipulation in conformity as the group WD that was not confined. Cortisol data support the hypothesis of impaired cortisol response as a consequence of oversecretion due to uneasiness during the short

  14. From microgravity to osmotic conditions: mechanical integration of plant cells in response to stress

    Science.gov (United States)

    Wojtaszek, Przemyslaw; Kasprowicz, Anna; Michalak, Michal; Janczara, Renata; Volkmann, Dieter; Baluska, Frantisek

    Chemical reactions and interactions between molecules are commonly thought of as being at the basis of Life. Research of recent years, however, is more and more evidently indicating that physical forces are profoundly affecting the functioning of life at all levels of its organiza-tion. To detect and to respond to such forces, plant cells need to be integrated mechanically. Cell walls are the outermost functional zone of plant cells. They surround the individual cells, and also form a part of the apoplast. In cell suspensions, cell walls are embedded in the cul-ture medium which can be considered as a superapoplast. Through physical and chemical interactions they provide a basis for the structural and functional cell wall-plasma membrane-cytoskeleton (WMC) continuum spanning the whole cell. Here, the working of WMC contin-uum, and the participation of signalling molecules, like NO, would be presented in the context of plant responses to stress. In addition, the effects of the changing composition of WMC continuum will be considered, with particular attention paid to the modifications of the WMC components. Plant cells are normally adapted to changing osmotic conditions, resulting from variable wa-ter availability. The appearance of the osmotic stress activates adaptory mechanisms. If the strength of osmotic stress grows relatively slowly over longer period of time, the cells are able to adapt to conditions that are lethal to non-adapted cells. During stepwise adaptation of tobacco BY-2 suspension cells to the presence of various osmotically active agents, cells diverged into independent, osmoticum type-specific lines. In response to ionic agents (NaCl, KCl), the adhe-sive properties were increased and randomly dividing cells formed clumps, while cells adapted to nonionic osmotica (mannitol, sorbitol, PEG) revealed ordered pattern of precisely positioned cell divisions, resulting in the formation of long cell files. Changes in the growth patterns were accompanied by

  15. Geophysical Responses of Hydrocarbon-impacted Zones at the Various Contamination Conditions

    Science.gov (United States)

    Kim, C.; Ko, K.; Son, J.; Kim, J.

    2008-12-01

    One controlled experiment and two field surveys were conducted to investigate the geoelectrical responses of hydrocarbon-contaminated zones, so called smeared zone, on the geophysical data at the hydrocarbon- contaminated sites with various conditions. One controlled physical model experiment with GPR using fresh gasoline and two different 3-D electrical resistivity investigations at the aged sites. One field site (former military facilities for arms maintenance) was mainly contaminated with lubricating oils and the other (former gas station) was contaminated with gasoline and diesel, respectively. The results from the physical model experiment show that GPR signals were enhanced when LNAPL was present as a residual saturation in the water-saturated system due to less attenuation of the electromagnetic energy through the soil medium of the hydrocarbon-impacted zone (no biodegradation), compared to when the medium was saturated with only water (no hydrocarbon impaction). In the former gas station site, 3-D resistivity results demonstrate that the highly contaminated zones were imaged with low resistivity anomalies since the biodegradation of petroleum hydrocarbons has been undergone for many years, causing the drastic increase in the TDS at the hydrocarbon-impacted zones. Finally, 3-D resistivity data obtained from the former military maintenance site show that the hydrocarbon-contaminated zones show high resistivity anomalies since the hydrocarbons such as lubricating oils at the contaminated soils were not greatly influenced by microbial degradation and has relatively well kept their original physical properties of high electrical resistivity. The results of the study illustrated that the hydrocarbon-impacted zones under various contamination conditions yielded various geophysical responses which include (1) enhanced GPR amplitudes at the fresh LNAPL (Gasoline to middle distillates) spill sites, (2) low electrical resistivity anomalies due to biodegradation at the

  16. Condition Help: A Patient- and Family-Initiated Rapid Response System.

    Science.gov (United States)

    Eden, Elizabeth L; Rack, Laurie L; Chen, Ling-Wan; Bump, Gregory M

    2017-03-01

    Rapid response teams (RRTs) help in delivering safe, timely care. Typically they are activated by clinicians using specific parameters. Allowing patients and families to activate RRTs is a novel intervention. The University of Pittsburgh Medical Center developed and implemented a patient- and family-initiated rapid response system called Condition Help (CH). When the CH system is activated, a patient care liaison or an on-duty administrator meets bedside with the unit charge nurse to address the patient's concerns. In this study, we collected demographic data, call reasons, call designations (safety or nonsafety), and outcome information for all CH calls made during the period January 2012 through June 2015. Two hundred forty patients/family members made 367 CH calls during the study period. Most calls were made by patients (76.8%) rather than family members (21.8%). Of the 240 patients, 43 (18%) made multiple calls; their calls accounted for 46.3% of all calls (170/367). Inadequate pain control was the reason for the call in most cases (48.2%), followed by dissatisfaction with staff (12.5%). The majority of calls involved nonsafety issues (83.4%) rather than safety issues (11.4%). In 41.4% of cases, a change in care was made. Patient- and family-initiated RRTs are designed to engage patients and families in providing safer care. In the CH system, safety issues are identified, but the majority of calls involve nonsafety issues. Journal of Hospital Medicine 2017;12:157-161. © 2017 Society of Hospital Medicine

  17. Growth Responses of Fish During Chronic Exposure of Metal Mixture under Laboratory Conditions

    Directory of Open Access Journals (Sweden)

    Saima Naz and Muhammad Javed

    2013-07-01

    Full Text Available Growth responses of five fish species viz. Catla catla, Labeo rohita, Cirrhina mrigala, Ctenopharyngodon idella and Hypophthalmichthys molitrix were determined, separately, under chronic exposure of binary mixture of metals (Zn+Ni at sub-lethal concentrations (1/3rd of LC50 for 12 weeks. Randomized complete block design (RCBD was followed to conduct this research work. The groups (10 fish each of Catla catla, Labeo rohita, Cirrhina mrigala, Ctenopharyngodon idella and Hypophthalmichthys molitrix having almost similar weights were investigated for their growth responses and metals bioaccumulation patterns in their body organs during chronic exposure of Zn+Ni mixture. The bioaccumulation of metals in the fish body organs viz. gills, liver, kidney, fins, bones, muscle and skin were also determined before and after growth trails under the stress of metals mixture. The exposure of fish to sub-lethal concentrations of mixture caused significant impacts on the average wet weight increments of five fish species. Ctenopharyngodon idella and Labeo rohita attained significantly higher weights, followed by that of Hypophthalmichthys molitrix, Cirrhina mrigala and Catla catla. However, the growth of metals mixture exposed fish species was significantly lesser than that of control fish (un-stressed. Significantly variable condition factor values reflected the degree of fish well-beings that correlated directly with fish growth and metal exposure concentration. Any significant change in feed intake, due to stress, is reflected in terms of fish growth showing the impacts of metal mixture on fish growth were either additive or antagonist / synergistic. Accumulation of all the metals in fish body followed the general order: liver>kidney>gills> skin >muscle> fins >bones.

  18. Energy crop (Sida hermaphrodita) fertilization using digestate under marginal soil conditions: A dose-response experiment

    Science.gov (United States)

    Nabel, Moritz; Bueno Piaz Barbosa, Daniela; Horsch, David; Jablonowski, Nicolai David

    2014-05-01

    The global demand for energy security and the mitigation of climate change are the main drivers pushing energy-plant production in Germany. However, the cultivation of these plants can cause land use conflicts since agricultural soil is mostly used for plant production. A sustainable alternative to the conventional cultivation of food-based energy-crops is the cultivation of special adopted energy-plants on marginal lands. To further increase the sustainability of energy-plant cultivation systems the dependency on synthetic fertilizers needs to be reduced via closed nutrient loops. In the presented study the energy-plant Sida hermaphrodita (Malvaceae) will be used to evaluate the potential to grow this high potential energy-crop on a marginal sandy soil in combination with fertilization via digestate from biogas production. With this dose-response experiment we will further identify an optimum dose, which will be compared to equivalent doses of NPK-fertilizer. Further, lethal doses and deficiency doses will be observed. Two weeks old Sida seedlings were transplanted to 1L pots and fertilized with six doses of digestate (equivalent to a field application of 5, 10, 20, 40, 80, 160t/ha) and three equivalent doses of NPK-fertilizer. Control plants were left untreated. Sida plants will grow for 45 days under greenhouse conditions. We hypothesize that the nutrient status of the marginal soil can be increased and maintained by defined digestate applications, compared to control plants suffering of nutrient deficiency due to the low nutrient status in the marginal substrate. The dose of 40t/ha is expected to give a maximum biomass yield without causing toxicity symptoms. Results shall be used as basis for further experiments on the field scale in a field trial that was set up to investigate sustainable production systems for energy crop production under marginal soil conditions.

  19. Exploring valid internal-control genes in Porphyra yezoensis (Bangiaceae) during stress response conditions

    Science.gov (United States)

    Wang, Wenlei; Wu, Xiaojie; Wang, Chao; Jia, Zhaojun; He, Linwen; Wei, Yifan; Niu, Jianfeng; Wang, Guangce

    2014-07-01

    To screen the stable expression genes related to the stress (strong light, dehydration and temperature shock) we applied Absolute real-time PCR technology to determine the transcription numbers of the selected test genes in P orphyra yezoensis, which has been regarded as a potential model species responding the stress conditions in the intertidal. Absolute real-time PCR technology was applied to determine the transcription numbers of the selected test genes in P orphyra yezoensis, which has been regarded as a potential model species in stress responding. According to the results of photosynthesis parameters, we observed that Y(II) and F v/ F m were significantly affected when stress was imposed on the thalli of P orphyra yezoensis, but underwent almost completely recovered under normal conditions, which were collected for the following experiments. Then three samples, which were treated with different grade stresses combined with salinity, irradiation and temperature, were collected. The transcription numbers of seven constitutive expression genes in above samples were determined after RNA extraction and cDNA synthesis. Finally, a general insight into the selection of internal control genes during stress response was obtained. We found that there were no obvious effects in terms of salinity stress (at salinity 90) on transcription of most genes used in the study. The 18S ribosomal RNA gene had the highest expression level, varying remarkably among different tested groups. RPS8 expression showed a high irregular variance between samples. GAPDH presented comparatively stable expression and could thus be selected as the internal control. EF-1α showed stable expression during the series of multiple-stress tests. Our research provided available references for the selection of internal control genes for transcripts determination of P. yezoensis.

  20. Behavioural responses to thermal conditions affect seasonal mass change in a heat-sensitive northern ungulate.

    Directory of Open Access Journals (Sweden)

    Floris M van Beest

    Full Text Available BACKGROUND: Empirical tests that link temperature-mediated changes in behaviour (activity and resource selection to individual fitness or condition are currently lacking for endotherms yet may be critical to understanding the effect of climate change on population dynamics. Moose (Alces alces are thought to suffer from heat stress in all seasons so provide a good biological model to test whether exposure to non-optimal ambient temperatures influence seasonal changes in body mass. Seasonal mass change is an important fitness correlate of large herbivores and affects reproductive success of female moose. METHODOLOGY/PRINCIPAL FINDINGS: Using GPS-collared adult female moose from two populations in southern Norway we quantified individual differences in seasonal activity budget and resource selection patterns as a function of seasonal temperatures thought to induce heat stress in moose. Individual body mass was recorded in early and late winter, and autumn to calculate seasonal mass changes (n = 52 over winter, n = 47 over summer. We found large individual differences in temperature-dependent resource selection patterns as well as within and between season variability in thermoregulatory strategies. As expected, individuals using an optimal strategy, selecting young successional forest (foraging habitat at low ambient temperatures and mature coniferous forest (thermal shelter during thermally stressful conditions, lost less mass in winter and gained more mass in summer. CONCLUSIONS/SIGNIFICANCE: This study provides evidence that behavioural responses to temperature have important consequences for seasonal mass change in moose living in the south of their distribution in Norway, and may be a contributing factor to recently observed declines in moose demographic performance. Although the mechanisms that underlie the observed temperature mediated habitat-fitness relationship remain to be tested, physiological state and individual variation in

  1. Behavioural responses to thermal conditions affect seasonal mass change in a heat-sensitive northern ungulate.

    Science.gov (United States)

    van Beest, Floris M; Milner, Jos M

    2013-01-01

    Empirical tests that link temperature-mediated changes in behaviour (activity and resource selection) to individual fitness or condition are currently lacking for endotherms yet may be critical to understanding the effect of climate change on population dynamics. Moose (Alces alces) are thought to suffer from heat stress in all seasons so provide a good biological model to test whether exposure to non-optimal ambient temperatures influence seasonal changes in body mass. Seasonal mass change is an important fitness correlate of large herbivores and affects reproductive success of female moose. Using GPS-collared adult female moose from two populations in southern Norway we quantified individual differences in seasonal activity budget and resource selection patterns as a function of seasonal temperatures thought to induce heat stress in moose. Individual body mass was recorded in early and late winter, and autumn to calculate seasonal mass changes (n = 52 over winter, n = 47 over summer). We found large individual differences in temperature-dependent resource selection patterns as well as within and between season variability in thermoregulatory strategies. As expected, individuals using an optimal strategy, selecting young successional forest (foraging habitat) at low ambient temperatures and mature coniferous forest (thermal shelter) during thermally stressful conditions, lost less mass in winter and gained more mass in summer. This study provides evidence that behavioural responses to temperature have important consequences for seasonal mass change in moose living in the south of their distribution in Norway, and may be a contributing factor to recently observed declines in moose demographic performance. Although the mechanisms that underlie the observed temperature mediated habitat-fitness relationship remain to be tested, physiological state and individual variation in thermal tolerance are likely contributory factors. Climate-related effects on animal

  2. Molecular Mechanisms Responsible for Neuron-Derived Conditioned Medium (NCM-Mediated Protection of Ischemic Brain.

    Directory of Open Access Journals (Sweden)

    Chi-Hsin Lin

    Full Text Available The protective value of neuron-derived conditioned medium (NCM in cerebral ischemia and the underlying mechanism(s responsible for NCM-mediated brain protection against cerebral ischemia were investigated in the study. NCM was first collected from the neuronal culture growing under the in vitro ischemic condition (glucose-, oxygen- and serum-deprivation or GOSD for 2, 4 or 6 h. Through the focal cerebral ischemia (bilateral CCAO/unilateral MCAO animal model, we discovered that ischemia/reperfusion (I/R-induced brain infarction was significantly reduced by NCM, given directly into the cistern magna at the end of 90 min of CCAO/MCAO. Immunoblocking and chemical blocking strategies were applied in the in vitro ischemic studies to show that NCM supplement could protect microglia, astrocytes and neurons from GOSD-induced cell death, in a growth factor (TGFβ1, NT-3 and GDNF and p-ERK dependent manner. Brain injection with TGFβ1, NT3, GDNF and ERK agonist (DADS alone or in combination, therefore also significantly decreased the infarct volume of ischemic brain. Moreover, NCM could inhibit ROS but stimulate IL-1β release from GOSD-treated microglia and limit the infiltration of IL-β-positive microglia into the core area of ischemic brain, revealing the anti-oxidant and anti-inflammatory activities of NCM. In overall, NCM-mediated brain protection against cerebral ischemia has been demonstrated for the first time in S.D. rats, due to its anti-apoptotic, anti-oxidant and potentially anti-glutamate activities (NCM-induced IL-1β can inhibit the glutamate-mediated neurotoxicity and restriction upon the infiltration of inflammatory microglia into the core area of ischemic brain. The therapeutic potentials of NCM, TGFβ1, GDNF, NT-3 and DADS in the control of cerebral ischemia in human therefore have been suggested and require further investigation.

  3. Modeling regeneration responses of big sagebrush (Artemisia tridentata) to abiotic conditions

    Science.gov (United States)

    Schlaepfer, Daniel R.; Lauenroth, William K.; Bradford, John B.

    2014-01-01

    Ecosystems dominated by big sagebrush, Artemisia tridentata Nuttall (Asteraceae), which are the most widespread ecosystems in semiarid western North America, have been affected by land use practices and invasive species. Loss of big sagebrush and the decline of associated species, such as greater sage-grouse, are a concern to land managers and conservationists. However, big sagebrush regeneration remains difficult to achieve by restoration and reclamation efforts and there is no regeneration simulation model available. We present here the first process-based, daily time-step, simulation model to predict yearly big sagebrush regeneration including relevant germination and seedling responses to abiotic factors. We estimated values, uncertainty, and importance of 27 model parameters using a total of 1435 site-years of observation. Our model explained 74% of variability of number of years with successful regeneration at 46 sites. It also achieved 60% overall accuracy predicting yearly regeneration success/failure. Our results identify specific future research needed to improve our understanding of big sagebrush regeneration, including data at the subspecies level and improved parameter estimates for start of seed dispersal, modified wet thermal-time model of germination, and soil water potential influences. We found that relationships between big sagebrush regeneration and climate conditions were site specific, varying across the distribution of big sagebrush. This indicates that statistical models based on climate are unsuitable for understanding range-wide regeneration patterns or for assessing the potential consequences of changing climate on sagebrush regeneration and underscores the value of this process-based model. We used our model to predict potential regeneration across the range of sagebrush ecosystems in the western United States, which confirmed that seedling survival is a limiting factor, whereas germination is not. Our results also suggested that modeled

  4. Tracking Biological and Ecosystem Responses to Changing Environmental Conditions in the Pacific Arctic

    Science.gov (United States)

    Grebmeier, J. M.; Cooper, L. W.; Frey, K. E.; Moore, S. E.

    2014-12-01

    Changing seasonal sea ice conditions and seawater temperatures strongly influence biological processes and marine ecosystems at high latitudes. In the Pacific Arctic, persistent regions termed "hotspots", are localized areas with high benthic macroinfaunal biomass that have been documented over four decades (see Figure). These regions are now being more formally tracked to relate physical forcing and ecosystem response as an Arctic Distributed Biological Observatory (DBO) supported by the US National Ocean Policy Implementation Plan and international partners. These hotspots are important foraging areas for upper trophic level benthic feeders, such as marine mammals and seabirds. South of St. Lawrence Island (SLI) in the northern Bering Sea, benthic feeding spectacled eiders, bearded seals and walruses are important winter consumers of infauna, such as bivalves and polychaetes. Gray whales have historically been a major summer consumer of benthic amphipods in the Chirikov Basin to the north of SLI, although summertime sightings of gray whales declined in the Chirikov from the 1980s up until at least 2002. The SE Chukchi Sea hotspot, as are the other hotspots, is maintained by export of high chlorophyll a that is produced locally as well as advected by water masses transiting northward through the system. Both walrus and gray whales are known to forage in this hotspot seasonally on high biomass levels of benthic prey. Notably the center of the highest benthic biomass regions has shifted northward in three of the DBO hotspots in recent years. This has coincided with changing sediment grain size, an indicator of current speed, and is also likely a response to changes in primary production in the region. Studies of these broad biological responses to changing physical drivers have been facilitated through development of the DBO cooperative effort by both US and international scientists. The DBO includes a series of coordinated, multi-trophic level observations that

  5. Conditional Dependence between Response Time and Accuracy: An Overview of its Possible Sources and Directions for Distinguishing between Them

    Science.gov (United States)

    Bolsinova, Maria; Tijmstra, Jesper; Molenaar, Dylan; De Boeck, Paul

    2017-01-01

    With the widespread use of computerized tests in educational measurement and cognitive psychology, registration of response times has become feasible in many applications. Considering these response times helps provide a more complete picture of the performance and characteristics of persons beyond what is available based on response accuracy alone. Statistical models such as the hierarchical model (van der Linden, 2007) have been proposed that jointly model response time and accuracy. However, these models make restrictive assumptions about the response processes (RPs) that may not be realistic in practice, such as the assumption that the association between response time and accuracy is fully explained by taking speed and ability into account (conditional independence). Assuming conditional independence forces one to ignore that many relevant individual differences may play a role in the RPs beyond overall speed and ability. In this paper, we critically consider the assumption of conditional independence and the important ways in which it may be violated in practice from a substantive perspective. We consider both conditional dependences that may arise when all persons attempt to solve the items in similar ways (homogeneous RPs) and those that may be due to persons differing in fundamental ways in how they deal with the items (heterogeneous processes). The paper provides an overview of what we can learn from observed conditional dependences. We argue that explaining and modeling these differences in the RPs is crucial to increase both the validity of measurement and our understanding of the relevant RPs. PMID:28261136

  6. Response of the Water Level in a Well to Earth Tides and Atmospheric Loading Under Unconfined Conditions

    Science.gov (United States)

    Rojstaczer, Stuart; Riley, Francis S.

    1990-08-01

    The response of the water level in a well to Earth tides and atmospheric loading under unconfined conditions can be explained if the water level is controlled by the aquifer response averaged over the saturated depth of the well. Because vertical averaging tends to diminish the influence of the water table, the response is qualitatively similar to the response of a well under partially confined conditions. When the influence of well bore storage can be ignored, the response to Earth tides is strongly governed by a dimensionless aquifer frequency Q'u. The response to atmospheric loading is strongly governed by two dimensionless vertical fluid flow parameters: a dimensionless unsaturated zone frequency, R, and a dimensionless aquifer frequency Qu. The differences between Q'u and Qu are generally small for aquifers which are highly sensitive to Earth tides. When Q'u and Qu are large, the response of the well to Earth tides and atmospheric loading approaches the static response of the aquifer under confined conditions. At small values of Q'u and Qu, well response to Earth tides and atmospheric loading is strongly influenced by water table drainage. When R is large relative to Qu, the response to atmospheric loading is strongly influenced by attenuation and phase shift of the pneumatic pressure signal in the unsaturated zone. The presence of partial penetration retards phase advance in well response to Earth tides and atmospheric loading. When the theoretical response of a phreatic well to Earth tides and atmospheric loading is fit to the well response inferred from cross-spectral estimation, it is possible to obtain estimates of the pneumatic diffusivity of the unsaturated zone and the vertical hydraulic conductivity of the aquifer.

  7. Response of tomato cultivars to different organic fertilizers under agro-climatic conditions of mingora, Swat

    International Nuclear Information System (INIS)

    Yousafzai, S.K.; Khan, S.M.; Khan, J.; Khan, S.A.; Hussain, I.; Naz, I.

    2016-01-01

    An experiment was conducted at Agricultural Research Institute (ARI) Mingora, Swat during 2013 to study the effect of different organic fertilizers of tomato cultivars under the agro-climatic conditions of Mingora, Swat. The experiment was conducted in randomized complete block design with split plot arrangements having four treatments with three replications. Almost all the traits showed significant differences for organic fertilizers and varieties, while their interactions had a varied response. The analyzed data showed that poultry manure gave maximum yield (24.65 t ha/sup -1/), followed by FYM (24.38 t ha/sup -1/) and mushroom compost (24.11 t ha/sup -1/ ) while minimum was recorded in plots where no organic fertilizer was used. The results revealed that cultivar, Rio Grand showed maximum number of plant survival percentage (98.33 percent), days to flowering (40.73), number of flowers plant/sup -1/ (6.23), number of fruit plant (25.67), fruit 3 weight (8.84 kg), number of leaves plant/sup -1/ (83.66), fruit size (64.70 cm/sup 3/) and total yield (25.67 t ha/sup -1/ ) in Farm Yard Manure (FYM). Considering the overall performance, it was found that the tomato cultivar Rio Grand was promising for yield and other characters where FYM was applied. (author)

  8. A Closed-Loop Control Strategy for Air Conditioning Loads to Participate in Demand Response

    Directory of Open Access Journals (Sweden)

    Xiaoqing Hu

    2015-08-01

    Full Text Available Thermostatically controlled loads (TCLs, such as air conditioners (ACs, are important demand response resources—they have a certain heat storage capacity. A change in the operating status of an air conditioner in a small range will not noticeably affect the users’ comfort level. Load control of TCLs is considered to be equivalent to a power plant of the same capacity in effect, and it can significantly reduce the system pressure to peak load shift. The thermodynamic model of air conditioning can be used to study the aggregate power of a number of ACs that respond to the step signal of a temperature set point. This paper analyzes the influence of the parameters of each AC in the group to the indoor temperature and the total load, and derives a simplified control model based on the two order linear time invariant transfer function. Then, the stability of the model and designs its Proportional-Integral-Differential (PID controller based on the particle swarm optimization (PSO algorithm is also studied. The case study presented in this paper simulates both scenarios of constant ambient temperature and changing ambient temperature to verify the proposed transfer function model and control strategy can closely track the reference peak load shifting curves. The study also demonstrates minimal changes in the indoor temperature and the users’ comfort level.

  9. Incorporating fan control into air-conditioning systems to improve energy efficiency and transient response

    International Nuclear Information System (INIS)

    Yeh, T.-J.; Chen, Yun-Jih; Hwang, Wei-Yang; Lin, Jin-Long

    2009-01-01

    Modern air-conditioners frequently incorporate variable-speed compressors and variable-opening expansion valves with feedback control to improve performance and power efficiency. Because making the fan speeds adjustable adds flexibility to the control design and thus can lead to further improvements in performance and efficiency, this paper proposes two control algorithms, respectively, incorporating the outdoor fan and the indoor fan as the additional control inputs for air-conditioning systems. Both of the control algorithms are designed based on a low-order, linear model obtained from system identification. The first algorithm, which modulates the outdoor fan speed, can reduce the steady state power consumption if the temperature difference between the condenser and the outdoor environment is controlled properly. The second algorithm, which adds one more degree of freedom to control by modulating the indoor fan speed, can improve the transient response because actuator saturations become less likely to occur. The two control algorithms are implemented on a split-type residential air-conditioner and their respective performance is validated experimentally.

  10. Detailed assessment of gene activation levels by multiple hypoxia-responsive elements under various hypoxic conditions.

    Science.gov (United States)

    Takeuchi, Yasuto; Inubushi, Masayuki; Jin, Yong-Nan; Murai, Chika; Tsuji, Atsushi B; Hata, Hironobu; Kitagawa, Yoshimasa; Saga, Tsuneo

    2014-12-01

    HIF-1/HRE pathway is a promising target for the imaging and the treatment of intractable malignancy (HIF-1; hypoxia-inducible factor 1, HRE; hypoxia-responsive element). The purposes of our study are: (1) to assess the gene activation levels resulting from various numbers of HREs under various hypoxic conditions, (2) to evaluate the bidirectional activity of multiple HREs, and (3) to confirm whether multiple HREs can induce gene expression in vivo. Human colon carcinoma HCT116 cells were transiently transfected by the constructs containing a firefly luciferase reporter gene and various numbers (2, 4, 6, 8, 10, and 12) of HREs (nHRE+, nHRE-). The relative luciferase activities were measured under various durations of hypoxia (6, 12, 18, and 24 h), O2 concentrations (1, 2, 4, 8, and 16 %), and various concentrations of deferoxamine mesylate (20, 40, 80, 160, and 320 µg/mL growth medium). The bidirectional gene activation levels by HREs were examined in the constructs (dual-luc-nHREs) containing firefly and Renilla luciferase reporter genes at each side of nHREs. Finally, to test whether the construct containing 12HRE and the NIS reporter gene (12HRE-NIS) can induce gene expression in vivo, SPECT imaging was performed in a mouse xenograft model. (1) gene activation levels by HREs tended to increase with increasing HRE copy number, but a saturation effect was observed in constructs with more than 6 or 8 copies of an HRE, (2) gene activation levels by HREs increased remarkably during 6-12 h of hypoxia, but not beyond 12 h, (3) gene activation levels by HREs decreased with increasing O2 concentrations, but could be detected even under mild hypoxia at 16 % O2, (4) the bidirectionally proportional activity of the HRE was confirmed regardless of the hypoxic severity, and (5) NIS expression driven by 12 tandem copies of an HRE in response to hypoxia could be visualized on in vivo SPECT imaging. The results of this study will help in the understanding and assessment of

  11. Sex differences in the behavioural and hypothalamic-pituitary-adrenal response to contextual fear conditioning in rats.

    Science.gov (United States)

    Daviu, Núria; Andero, Raül; Armario, Antonio; Nadal, Roser

    2014-11-01

    In recent years, special attention is being paid to sex differences in susceptibility to disease. In this regard, there is evidence that male rats present higher levels of both cued and contextual fear conditioning than females. However, little is known about the concomitant hypothalamic-pituitary-adrenal (HPA) axis response to those situations which are critical in emotional memories. Here, we studied the behavioural and HPA responses of male and female Wistar rats to context fear conditioning using electric footshock as the aversive stimulus. Fear-conditioned rats showed a much greater ACTH and corticosterone response than those merely exposed to the fear conditioning chamber without receiving shocks. Moreover, males presented higher levels of freezing whereas HPA axis response was greater in females. Accordingly, during the fear extinction tests, female rats consistently showed less freezing and higher extinction rate, but greater HPA activation than males. Exposure to an open-field resulted in lower activity/exploration in fear-conditioned males, but not in females, suggesting greater conditioned cognitive generalization in males than females. It can be concluded that important sex differences in fear conditioning are observed in both freezing and HPA activation, but the two sets of variables are affected in the opposite direction: enhanced behavioural impact in males, but enhanced HPA responsiveness in females. Thus, the role of sex differences on fear-related stimuli may depend on the variables chosen to evaluate it, the greater responsiveness of the HPA axis in females perhaps being an important factor to be further explored. Copyright © 2014 Elsevier Inc. All rights reserved.

  12. Lesions of the paraventricular nucleus of the thalamus differentially affect sign- and goal-tracking conditioned responses

    Science.gov (United States)

    Haight, Joshua L.; Fraser, Kurt M.; Akil, Huda; Flagel, Shelly B.

    2015-01-01

    Recently evidence has emerged suggesting a role for the paraventricular nucleus of the thalamus (PVT) in the processing of reward-associated cues. However, the specific role of the PVT in these processes has yet to be elucidated. Here we use an animal model that captures individual variation in response to discrete reward-associated cues to further assess the role of the PVT in stimulus-reward learning. When rats are exposed to a Pavlovian conditioning paradigm, wherein a discrete cue predicts food reward, two distinct conditioned responses emerge. Some rats, termed sign-trackers, approach and manipulate the cue; whereas others, termed goal-trackers, approach the location of reward delivery upon cue presentation. For both sign- and goal-trackers the cue is a predictor; but only for sign-trackers is it also an incentive stimulus. We investigated the role of the PVT in the acquisition and expression of these conditioned responses using an excitotoxic lesion. Results indicate that PVT lesions prior to acquisition amplify the differences between phenotypes—increasing sign-tracking and attenuating goal-tracking behavior. Lesions of the PVT after rats had acquired their respective conditioned responses also attenuated the expression of the goal-tracking response, and increased the sign-tracking response, but did so selectively in goal-trackers. These results suggest that the PVT acts to suppress the attribution of incentive salience to reward cues, as disruption of the functional activity within this structure enhances the tendency to sign-track. PMID:26228683

  13. Responses of the tropical gorgonian coral Eunicea fusca to ocean acidification conditions

    Science.gov (United States)

    Gómez, C. E.; Paul, V. J.; Ritson-Williams, R.; Muehllehner, N.; Langdon, C.; Sánchez, J. A.

    2015-06-01

    Ocean acidification can have negative repercussions from the organism to ecosystem levels. Octocorals deposit high-magnesium calcite in their skeletons, and according to different models, they could be more susceptible to the depletion of carbonate ions than either calcite or aragonite-depositing organisms. This study investigated the response of the gorgonian coral Eunicea fusca to a range of CO2 concentrations from 285 to 4,568 ppm (pH range 8.1-7.1) over a 4-week period. Gorgonian growth and calcification were measured at each level of CO2 as linear extension rate and percent change in buoyant weight and calcein incorporation in individual sclerites, respectively. There was a significant negative relationship for calcification and CO2 concentration that was well explained by a linear model regression analysis for both buoyant weight and calcein staining. In general, growth and calcification did not stop in any of the concentrations of pCO2; however, some of the octocoral fragments experienced negative calcification at undersaturated levels of calcium carbonate (>4,500 ppm) suggesting possible dissolution effects. These results highlight the susceptibility of the gorgonian coral E. fusca to elevated levels of carbon dioxide but suggest that E. fusca could still survive well in mid-term ocean acidification conditions expected by the end of this century, which provides important information on the effects of ocean acidification on the dynamics of coral reef communities. Gorgonian corals can be expected to diversify and thrive in the Atlantic-Eastern Pacific; as scleractinian corals decline, it is likely to expect a shift in these reef communities from scleractinian coral dominated to octocoral/soft coral dominated under a "business as usual" scenario of CO2 emissions.

  14. Physiological and Molecular Response of Ostrich to the Seasonal and Diurnal Variations in Egyptian conditions

    International Nuclear Information System (INIS)

    Khalil, M.H.; Khalifa, H.H; Elaroussi, M.A.; Elsayed, M.A.; Basuony, H.A.

    2013-01-01

    Twelve immature ostrich›s birds, 7 months old were used to evaluate the effect of ambient temperature variation and diurnal effect on response changes of some physiological and chemical parameters. All birds were reared out doors and exposed to daily ambient temperatures fluctuations during summer and winter. Blood samples were taken twice, one in the morning at 7 Am and once in the afternoon at 3 Pm during a representative 7 hot days of June (summer) (40±2ºC) and the 7 cold days of January (winter) (18±2ºC). Serum calcium, inorganic phosphorus, sodium, potassium, uric acid concentrations and aldosterone level were determined. The amount of total body water (TBW) and serum heat shock proteins (HSP) were estimated. Serum calcium, phosphorus, sodium and potassium concentrations in ostrich were significantly decreased, while uric acid concentration and aldosterone hormone level were significantly increased in summer as compared in winter during both at morning and at afternoon periods. Concerning the diurnal variation, serum calcium, phosphorus, sodium and potassium concentrations and aldosterone hormone level in ostrich were significantly increased, while uric acid concentration was significantly decreased at morning as compared at afternoon during both summer and winter seasons. TBW was significantly higher in summer season by 15.04% than winter season. It is concluded from the present study that heat or cold stress has a negative effect on most of the parameters studied and we recommend must be supplement diet with some nutrients like vitamins C, and E, sodium bicarbonate or yeast to overcome the negative effect and to better perform under such conditions

  15. Growth Responses of Acacia mangium and Paraserianthes falcataria Seedlings on Different Soil Origin under Nursery Condition

    Directory of Open Access Journals (Sweden)

    Tirtha Ayu Paramitha

    2015-12-01

    Full Text Available The objective of the present study was to examine the growth responses of Acacia mangium (mangium and Paraserianthes falcataria (sengon seedlings growing on different soil origin under nursery condition. This study was started in September 2012 and terminated in March 2013.  The seedlings were grown from seeds sown in a plastic box filled with sterilized sands. One week after sowing, the seedlings were transplanted into polybags contained sterilized soils originated from secondary forest, Imperata cylindrica grassland and ex-coal mining. The number of all seedlings were 180 seedlings consisted of 3 different soils, 2 species of seedlings with 10 seedlings replicated 3 times. Assessment was conducted one week after transplanting, then subsequently monitored every 2 weeks, except dry weighing and counting nodules were performed at the end of the study. A completely randomized design was used in this study. The data was analyzed using Costat software. The study resulted that the different of soil origin influenced on all growth variables of mangium and sengon of 4.5 months old. The survival rate of seedlings, height and diameter increments, dry weight and root nodules were better in both species of seedlings growing on soil originated from secondary forest and Imperata grassland compared with the soil from ex-coal mining. But the survival rates of sengon seedlings were higher than that of mangium on these three soils. The highest dry weight of sengon seedlings was achieved on soil originated from secondary forest. In the present study, soil originated from secondary forest increased more in weight of shoot than root, so that the shoot-root ratio was unbalanced more than one. Based on the results of this study, it is recommended that soil from secondary forest and Imperata grassland can be used as growing media for mangium and sengon seedlings in the nursery.

  16. The lipid response of aerobic marine methanotroph communities under changing environmental conditions.

    Science.gov (United States)

    Rush, D.; Villanueva, L.; van der Meer, M.; S Sinninghe Damsté, J.

    2017-12-01

    Methane (CH4) originating from marine environments accounts for a significant amount of atmospheric greenhouse gas. Aerobic methanotrophs, which convert CH4 to CO­2, are responsible for quenching a part of this methane before its release. Modern-day climate projections show a rapid shift towards a warmer, more acidic ocean. How do these important methanotrophic communities respond to such changes to their environment? Here, we present the results of microcosm experiments from three marine regions influenced by CH4. Particulate organic matter and sediment were collected from the Black Sea, the Baltic Sea, and the North Sea, at depths ideal for aerobic methanotroph communities at the time of sampling (e.g. oxic, in area of active CH4 release). These were incubated under different temperatures, pHs, and labelled 13CH4 concentrations. We monitored methane concentration in these microcosms as an indication of 13CH4 consumption by methanotrophs. Once the methane concentration was lipids of the organisms oxidising methane in order to elucidate which organisms are performing methane oxidation and whether they synthesize specific biomarker lipids. Particular attention will be paid to the abundances and diversity of bacteriohopanepolyol lipids, known methanotroph biomarkers. The ultimate goal of our investigation is to determine the effect changes in these environmental parameters have on aerobic methanotroph community structures and their lipid fingerprints. By establishing reliable biomarker lipids for aerobic methanotrophy at certain conditions, we will then be able to investigate the contribution of aerobic methanotrophy throughout Earth's history, especially at times when CH4 concentrations were higher than they are at present.

  17. Cerebral responses and role of the prefrontal cortex in conditioned pain modulation: an fMRI study in healthy subjects

    Science.gov (United States)

    Bogdanov, Volodymyr B.; Viganò, Alessandro; Noirhomme, Quentin; Bogdanova, Olena V.; Guy, Nathalie; Laureys, Steven; Renshaw, Perry F.; Dallel, Radhouane; Phillips, Christophe; Schoenen, Jean

    2017-01-01

    The mechanisms underlying conditioned pain modulation (CPM) are multifaceted. We searched for a link between individual differences in prefrontal cortex activity during multi-trial heterotopic noxious cold conditioning and modulation of the cerebral response to phasic heat pain. In 24 healthy female subjects, we conditioned laser heat stimuli to the left hand by applying alternatively ice-cold or lukewarm compresses to the right foot. We compared pain ratings with cerebral fMRI BOLD responses. We also analyzed the relation between CPM and BOLD changes produced by the heterotopic cold conditioning itself, as well as the impact of anxiety and habituation of cold-pain ratings. Specific cerebral activation was identified in precuneus and left posterior insula/SII, respectively, during early and sustained phases of cold application. During cold conditioning, laser pain decreased (n = 7), increased (n = 10) or stayed unchanged (n = 7). At the individual level, the psychophysical effect was directly proportional to the cold-induced modulation of the laser-induced BOLD response in left posterior insula/SII. The latter correlated with the BOLD response recorded 80 s earlier during the initial 10-s phase of cold application in anterior cingulate, orbitofrontal and lateral prefrontal cortices. High anxiety and habituation of cold pain were associated with greater laser heat-induced pain during heterotopic cold stimulation. The habituation was also linked to the early cold-induced orbitofrontal responses. We conclude that individual differences in conditioned pain modulation are related to different levels of prefrontal cortical activation by the early part of the conditioning stimulus, possibly due to different levels in trait anxiety. PMID:25461267

  18. Actual measurement, hygrothermal response experiment and growth prediction analysis of microbial contamination of central air conditioning system in Dalian, China.

    Science.gov (United States)

    Lv, Yang; Hu, Guangyao; Wang, Chunyang; Yuan, Wenjie; Wei, Shanshan; Gao, Jiaoqi; Wang, Boyuan; Song, Fangchao

    2017-04-03

    The microbial contamination of central air conditioning system is one of the important factors that affect the indoor air quality. Actual measurement and analysis were carried out on microbial contamination in central air conditioning system at a venue in Dalian, China. Illumina miseq method was used and three fungal samples of two units were analysed by high throughput sequencing. Results showed that the predominant fungus in air conditioning unit A and B were Candida spp. and Cladosporium spp., and two fungus were further used in the hygrothermal response experiment. Based on the data of Cladosporium in hygrothermal response experiment, this paper used the logistic equation and the Gompertz equation to fit the growth predictive model of Cladosporium genera in different temperature and relative humidity conditions, and the square root model was fitted based on the two environmental factors. In addition, the models were carried on the analysis to verify the accuracy and feasibility of the established model equation.

  19. Staphylococcus aureus Esx Factors Control Human Dendritic Cell Functions Conditioning Th1/Th17 Response

    Directory of Open Access Journals (Sweden)

    Melania Cruciani

    2017-07-01

    Full Text Available The opportunistic pathogen Staphylococcus aureus (S. aureus is a major cause of nosocomial- and community-acquired infections. In addition, many antibiotic-resistant strains are emerging worldwide, thus, there is an urgent unmet need to pinpoint novel therapeutic and prophylactic strategies. In the present study, we characterized the impact of infection with the pandemic methicillin-resistant USA300 S. aureus strain on human primary dendritic cells (DC, key initiators and regulators of immune responses. In particular, among staphylococcal virulence factors, the function of EsxA and EsxB, two small acidic dimeric proteins secreted by the type VII-like secretion system Ess (ESAT-6-like secretion system, was investigated in human DC setting. A comparative analysis of bacterial entry, replication rate as well as DC maturation, apoptosis, signaling pathway activation and cytokine production was performed by using wild type (wt USA300 and three isogenic mutants carrying the deletion of esxA (ΔesxA, esxB (ΔesxB, or both genes (ΔesxAB. The S. aureus mutant lacking only the EsxA protein (ΔesxA stimulated a stronger pro-apoptotic phenotype in infected DC as compared to wt USA300, ΔesxAB, and ΔesxB strains. When the mutant carrying the esxB deletion (ΔesxB was analyzed, a higher production of both regulatory and pro-inflammatory mediators was found in the infected DC with respect to those challenged with the wt counterpart and the other esx mutants. In accordance with these data, supernatant derived from ΔesxB-infected DC promoted a stronger release of both IFN-γ and IL-17 from CD4+ T cells as compared with those conditioned with supernatants derived from wild type USA300-, ΔesxAB-, and ΔesxA-infected cultures. Although, the interaction of S. aureus with human DC is not yet fully understood, our data suggest that both cytokine production and apoptotic process are modulated by Esx factors, thus indicating a possible role of these proteins in the

  20. Evolution of Pine Island Glacier subglacial conditions in response to 18 years of ice flow acceleration

    Science.gov (United States)

    Brisbourne, A.; Bougamont, M. H.; Christoffersen, P.; Cornford, S. L.; Nias, I.; Vaughan, D.; Smith, A.

    2017-12-01

    Antarctica's main contribution to sea-level rise originates from the Amundsen Coast, when warm ocean water intrudes onto the continental shelf. As a result, strong melting beneath the ice shelves induces thinning near the grounding line of glaciers, which is ensued by large ice flow speed up diffusing rapidly inland. In particular, ice loss from Pine Island Glacier (PIG) accounts for 20% of the total ice loss in West Antarctica, amounting to 0.12 mm yr-1 of global sea-level rise. Forecasting the future flow of Amundsen Coast glaciers is however hindered by large uncertainties regarding how the thinning initiated at the grounding line is transmitted upstream, and how the grounded flow will ultimately respond. This work aims at elucidating the role of subglacial processes beneath PIG tributaries in modulating the ice flow response to frontal perturbations. We used the Community Ice Sheet Model (CISM 2.0) to perform numerical inversions of PIG surface velocity as observed in 1996 and 2014. Over that time period, ice flow acceleration has been widespread over PIG's basin, and the inversions provide insights into the related evolution of the basal thermal and stress conditions. We assume the latter to be directly related to changes in the properties of a soft sediment (till) layer known to exist beneath PIG. We find that the overall bed strength has weakened by 18% in the region of enhanced flow, and that the annual melt production for PIG catchment increased by 25% between 1996 and 2014. Specifically, regions of high melt production are located in the southern tributaries, where the overall stronger bed allows for more frictional melting. However, we find no significant and widespread change in the basal strength of that region, and we infer that the water produced is transported away in a concentrated hydrological system, without much interaction with the till layer. In contrast, we find that relatively less basal melting occurs elsewhere in the catchment, where the

  1. Conditioned Subjective Responses to Socially Relevant Stimuli in Social Anxiety Disorder and Subclinical Social Anxiety.

    Science.gov (United States)

    Tinoco-González, Daniella; Fullana, Miquel Angel; Torrents-Rodas, David; Bonillo, Albert; Vervliet, Bram; Pailhez, Guillem; Farré, Magí; Andión, Oscar; Perez, Víctor; Torrubia, Rafael

    2015-01-01

    Although enhanced fear conditioning has been implicated in the origins of social anxiety disorder (SAD), laboratory evidence in support of this association is limited. Using a paradigm employing socially relevant unconditioned stimuli, we conducted two separate studies to asses fear conditioning in individuals with SAD and non-clinical individuals with high social anxiety (subclinical social anxiety [SSA]). They were compared with age-matched and gender-matched individuals with another anxiety disorder (panic disorder with agoraphobia) and healthy controls (Study 1) and with individuals with low social anxiety (Study 2). Contrary to our expectations, in both studies, self-report measures (ratings of anxiety, unpleasantness and arousal to the conditioned stimuli) of fear conditioning failed to discriminate between SAD or SSA and the other participant groups. Our results suggest that enhanced fear conditioning does not play a major role in pathological social anxiety. We used a social conditioning paradigm to study fear conditioning in clinical and subclinical social anxiety. We found no evidence of enhanced fear conditioning in social anxiety individuals. Enhanced fear conditioning may not be a hallmark of pathological social anxiety. Copyright © 2014 John Wiley & Sons, Ltd.

  2. Physiological Signals and Their Fractal Response to Stress Conditions, Environmental Changes and Neurodegenerative Diseases

    National Research Council Canada - National Science Library

    Scafetta, N; Moon, R. E; West, B. J

    2006-01-01

    .... Some of these studies have been intended to develop more reliable methodologies for understanding how biological systems respond to peculiar altered conditions induced by internal stress, environment...

  3. Generalized Unsafety Theory of Stress: Unsafe Environments and Conditions, and the Default Stress Response

    Directory of Open Access Journals (Sweden)

    Jos F. Brosschot

    2018-03-01

    Full Text Available Prolonged physiological stress responses form an important risk factor for disease. According to neurobiological and evolution-theoretical insights the stress response is a default response that is always “on” but inhibited by the prefrontal cortex when safety is perceived. Based on these insights the Generalized Unsafety Theory of Stress (GUTS states that prolonged stress responses are due to generalized and largely unconsciously perceived unsafety rather than stressors. This novel perspective necessitates a reconstruction of current stress theory, which we address in this paper. We discuss a variety of very common situations without stressors but with prolonged stress responses, that are not, or not likely to be caused by stressors, including loneliness, low social status, adult life after prenatal or early life adversity, lack of a natural environment, and less fit bodily states such as obesity or fatigue. We argue that in these situations the default stress response may be chronically disinhibited due to unconsciously perceived generalized unsafety. Also, in chronic stress situations such as work stress, the prolonged stress response may be mainly caused by perceived unsafety in stressor-free contexts. Thus, GUTS identifies and explains far more stress-related physiological activity that is responsible for disease and mortality than current stress theories.

  4. Generalized Unsafety Theory of Stress: Unsafe Environments and Conditions, and the Default Stress Response.

    Science.gov (United States)

    Brosschot, Jos F; Verkuil, Bart; Thayer, Julian F

    2018-03-07

    Prolonged physiological stress responses form an important risk factor for disease. According to neurobiological and evolution-theoretical insights the stress response is a default response that is always "on" but inhibited by the prefrontal cortex when safety is perceived. Based on these insights the Generalized Unsafety Theory of Stress (GUTS) states that prolonged stress responses are due to generalized and largely unconsciously perceived unsafety rather than stressors. This novel perspective necessitates a reconstruction of current stress theory, which we address in this paper. We discuss a variety of very common situations without stressors but with prolonged stress responses, that are not, or not likely to be caused by stressors, including loneliness, low social status, adult life after prenatal or early life adversity, lack of a natural environment, and less fit bodily states such as obesity or fatigue. We argue that in these situations the default stress response may be chronically disinhibited due to unconsciously perceived generalized unsafety. Also, in chronic stress situations such as work stress, the prolonged stress response may be mainly caused by perceived unsafety in stressor-free contexts. Thus, GUTS identifies and explains far more stress-related physiological activity that is responsible for disease and mortality than current stress theories.

  5. Conditions and Strategies of Creating Company Value on the Basis of Corporate Social Responsibility – Synthetic Presentation

    Directory of Open Access Journals (Sweden)

    Anna Doś

    2011-11-01

    Full Text Available The aim of an enterprise is to increase its value. This growth can be achieved if initiated socially responsible activities improve the value drivers. The company’s specificity, type of its environment and their mutual reactions create conditions conducive to improvement of the driving forces of value by being socially responsible. Bearing this observation in mind we can formulate five strategies of creating value based on social responsibility. These are strategies of perfection, positive selection, surroundings modification, transformation and transposition.

  6. The growth response of plants to elevated CO2 under non-optimal environmental conditions

    NARCIS (Netherlands)

    Poorter, H.; Pérez-Soba, M.

    2001-01-01

    Under benign environmental conditions, plant growth is generally stimulated by elevated atmospheric CO2 concentrations. When environmental conditions become sub- or supra-optimal for growth, changes in the biomass enhancement ratio (BER; total plant biomass at elevated CO2 divided by plant biomass

  7. Chronic Lateral Epicondylalgia Does Not Exhibit Mechanical Pain Modulation in Response to Noxious Conditioning Heat Stimulus.

    Science.gov (United States)

    Lim, Edwin Choon Wyn; Sterling, Michele; Vicenzino, Bill

    2017-10-01

    The impaired attenuation of pain by the application of a noxious conditioning stimulus at a segmentally distinct site, known as conditioned pain modulation (CPM), has been implicated in clinical pain states. Chronic lateral epicondylalgia (LE), which is characterized by lower pressure pain thresholds (PPTs) at sites remote to the affected elbow and spinal cord hyperexcitability, is a clinical pain state that might plausibly involve less efficacious CPM. This study aimed to determine whether LE exhibits a less efficacious CPM compared with that in pain-free controls. Results: Twenty participants with LE, aged 50.7 years (SD=7.05) and who had their condition for 10.2 months (range: 2 to 80 mo), were matched by age and sex to 22 pain-free participants. All participants indicated their PPT over the lateral epicondyle(s) before and during a conditioning noxious heat stimulus that was applied over the calf. A CPM score was calculated as the difference between the PPT before and during the heat pain-conditioning stimulus expressed as a percentage of PPT before the heat pain-conditioning stimulus. The condition (LE vs. control) by side (affected vs. unaffected) analysis of variance revealed a significant condition effect (P=0.001), but not side effect (P=0.192) or side-by-condition interaction effect (P=0.951). Follow-up tests for the effect of condition revealed a mean deficit in CPM of -24.5% (95% confidence interval, -38.0 to -11.0) in LE compared with that in pain-free participants. The results that suggest an impaired ability to modulate pain might be associated with the previously observed spinal cord hyperexcitability and the mechanical hyperalgesia that characterizes LE.

  8. The active sequence in the acth molecule responsible for inhibition of the extinction of conditioned avoidance behaviour in rats

    NARCIS (Netherlands)

    Greven, H.M.; Wied, D. de

    1967-01-01

    The effect of structural analogues of the N-terminal decapeptide of ACTH on inhibition of extinction of a conditioned avoidance response in rats has been studied. Studies involving the relation between chain length and behavioural activity revealed that the sequence 4–10 is the shortest peptide

  9. Early feeding and early life housing conditions influence the response towards a noninfectious lung challenge in broilers.

    Science.gov (United States)

    Simon, K; de Vries Reilingh, G; Bolhuis, J E; Kemp, B; Lammers, A

    2015-09-01

    Early life conditions such as feed and water availability immediately post hatch (PH) and housing conditions may influence immune development and therefore immune reactivity later in life. The current study addressed the consequences of a combination of these 2 early life conditions for immune reactivity, i.e., the specific antibody response towards a non-infectious lung challenge. Broiler chicks received feed and water either immediately p.h. or with a 72 h delay and were either reared in a floor or a cage system. At 4 weeks of age, chicks received either an intra-tracheally administered Escherichia coli lipopolysaccharide (LPS)/Human Serum Albumin (HUSA) challenge or a placebo, and antibody titers were measured up to day 14 after administration of the challenge. Chicks housed on the floor and which had a delayed access to feed p.h. showed the highest antibody titers against HuSA. These chicks also showed the strongest sickness response and poorest performance in response to the challenge, indicating that chicks with delayed access to feed might be more sensitive to an environment with higher antigenic pressure. In conclusion, results from the present study show that early life feeding strategy and housing conditions influence a chick's response to an immune challenge later in life. These 2 early life factors should therefore be taken into account when striving for a balance between disease resistance and performance in poultry. © 2015 Poultry Science Association Inc.

  10. Effect of weather data aggregation on regional crop simulation for different crops, production conditions, and response variables

    NARCIS (Netherlands)

    Zhao, Gang; Hoffmann, Holger; Bussel, Van L.G.J.; Enders, Andreas; Specka, Xenia; Sosa, Carmen; Yeluripati, Jagadeesh; Tao, Fulu; Constantin, Julie; Raynal, Helene; Teixeira, Edmar; Grosz, Balázs; Doro, Luca; Zhao, Zhigan; Nendel, Claas; Kiese, Ralf; Eckersten, Henrik; Haas, Edwin; Vanuytrecht, Eline; Wang, Enli; Kuhnert, Matthias; Trombi, Giacomo; Moriondo, Marco; Bindi, Marco; Lewan, Elisabet; Bach, Michaela; Kersebaum, Kurt Christian; Rötter, Reimund; Roggero, Pier Paolo; Wallach, Daniel; Cammarano, Davide; Asseng, Senthold; Krauss, Gunther; Siebert, Stefan

    2015-01-01

    We assessed the weather data aggregation effect (DAE) on the simulation of cropping systems for different crops, response variables, and production conditions. Using 13 processbased crop models and the ensemble mean, we simulated 30 yr continuous cropping systems for 2 crops (winter wheat and

  11. Global quantification of contrasting leaf life span strategies for deciduous and evergreen species in response to environmental conditions.

    NARCIS (Netherlands)

    van Ommen Kloeke, A.E.E.; Douma, J.C.; Ordonez Barragan, J.C.; Reick, P.B.; van Bodegom, P.M.

    2012-01-01

    Aim Species with deciduous and evergreen leaf habits typically differ in leaf life span (LLS). Yet quantification of the response of LLS, within each habit, to key environmental conditions is surprisingly lacking. The aim of this study is to quantify LLS strategies of the two leaf habits under

  12. Infant Long-Term Memory for a Conditioned Response and Intelligence Test Performance at 2 Years of Age.

    Science.gov (United States)

    Fagen, Jeffrey W.; And Others

    To find predictive relations between measures taken in infancy and later scores on intelligence tests, a study was made that measured in the infant those cognitive processes examined later in life. Operant conditioning tasks were employed which required 3-, 7-, and 11-month-old infants to execute some response to produce an environmental…

  13. Speech auditory brainstem response (speech ABR) characteristics depending on recording conditions, and hearing status: an experimental parametric study.

    Science.gov (United States)

    Akhoun, Idrick; Moulin, Annie; Jeanvoine, Arnaud; Ménard, Mikael; Buret, François; Vollaire, Christian; Scorretti, Riccardo; Veuillet, Evelyne; Berger-Vachon, Christian; Collet, Lionel; Thai-Van, Hung

    2008-11-15

    Speech elicited auditory brainstem responses (Speech ABR) have been shown to be an objective measurement of speech processing in the brainstem. Given the simultaneous stimulation and recording, and the similarities between the recording and the speech stimulus envelope, there is a great risk of artefactual recordings. This study sought to systematically investigate the source of artefactual contamination in Speech ABR response. In a first part, we measured the sound level thresholds over which artefactual responses were obtained, for different types of transducers and experimental setup parameters. A watermelon model was used to model the human head susceptibility to electromagnetic artefact. It was found that impedances between the electrodes had a great effect on electromagnetic susceptibility and that the most prominent artefact is due to the transducer's electromagnetic leakage. The only artefact-free condition was obtained with insert-earphones shielded in a Faraday cage linked to common ground. In a second part of the study, using the previously defined artefact-free condition, we recorded speech ABR in unilateral deaf subjects and bilateral normal hearing subjects. In an additional control condition, Speech ABR was recorded with the insert-earphones used to deliver the stimulation, unplugged from the ears, so that the subjects did not perceive the stimulus. No responses were obtained from the deaf ear of unilaterally hearing impaired subjects, nor in the insert-out-of-the-ear condition in all the subjects, showing that Speech ABR reflects the functioning of the auditory pathways.

  14. Comparison of Regression Techniques to Predict Response of Oilseed Rape Yield to Variation in Climatic Conditions in Denmark

    DEFF Research Database (Denmark)

    Sharif, Behzad; Makowski, David; Plauborg, Finn

    2017-01-01

    Statistical regression models represent alternatives to process-based dynamic models for predicting the response of crop yields to variation in climatic conditions. Regression models can be used to quantify the effect of change in temperature and precipitation on yields. However, it is difficult ...

  15. Effects of social conditions during early development on stress response and personality traits in great tits (Parus major)

    NARCIS (Netherlands)

    Naguib, M.; Floercke, C.; Oers, van K.

    2011-01-01

    Environmental conditions during early development play a crucial role in shaping an organism's phenotype. To test how social group size affects stress response and behavioral characteristics, we used great tits (Parus major) from selection lines for exploratory behavior, a proxy for an avian

  16. Responsible aquaculture in 2050: Valuing local conditions and human innovations will be key to success

    NARCIS (Netherlands)

    Diana, J.S.; Egna, H.S.; Chopin, T.; Peterson, M.S.; Cao, L.; Pomeroy, R.; Verdegem, M.C.J.; Slack, W.T.; Bondad-Reantaso, M.G.; Cabello, F.

    2013-01-01

    As aquaculture production expands, we must avoid mistakes made during increasing intensification of agriculture. Understanding environmental impacts and measures to mitigate them is important for designing responsible aquaculture production systems. There are four realistic goals that can make

  17. ε-Polylysine-based thermo-responsive adsorbents for immunoglobulin adsorption-desorption under mild conditions.

    Science.gov (United States)

    Maruyama, Masashi; Shibuya, Keisuke

    2017-08-22

    Thermo-responsive adsorbents for immunoglobulin G (IgG) employing ε-polylysine (EPL) as a polymer backbone were developed. The introduction of mercaptoethylpyridine (MEP) as an IgG-binding ligand and hydrophobization of side chains afforded thermo-responsive IgG adsorbents, whose thermo-responsive IgG desorption ratio was up to 88% (EPL/MEP derivative 3m). The changes in surface densities of active MEP groups, which are caused by thermal conformational changes of the adsorbents, play key roles for IgG desorption. Although a trade-off of IgG adsorption capacity and IgG desorption ratio was observed, the present study offers a novel molecular design for thermo-responsive adsorbents with high synthetic accessibility and potentially low toxicity.

  18. Intercomparison of fast response commercial gas analysers for nitrous oxide flux measurements under field conditions

    Science.gov (United States)

    Rannik, Ü.; Haapanala, S.; Shurpali, N. J.; Mammarella, I.; Lind, S.; Hyvönen, N.; Peltola, O.; Zahniser, M.; Martikainen, P. J.; Vesala, T.

    2015-01-01

    Four gas analysers capable of measuring nitrous oxide (N2O) concentration at a response time necessary for eddy covariance flux measurements were operated from spring until winter 2011 over a field cultivated with reed canary grass (RCG, Phalaris arundinacea, L.), a perennial bioenergy crop in eastern Finland. The instruments were TGA100A (Campbell Scientific Inc.), CW-TILDAS-CS (Aerodyne Research Inc.), N2O / CO-23d (Los Gatos Research Inc.) and QC-TILDAS-76-CS (Aerodyne Research Inc.). The period with high emissions, lasting for about 2 weeks after fertilization in late May, was characterized by an up to 2 orders of magnitude higher emission, whereas during the rest of the campaign the N2O fluxes were small, from 0.01 to 1 nmol m-2 s-1. Two instruments, CW-TILDAS-CS and N2O / CO-23d, determined the N2O exchange with minor systematic difference throughout the campaign, when operated simultaneously. TGA100A produced the cumulatively highest N2O estimates (with 29% higher values during the period when all instruments were operational). QC-TILDAS-76-CS obtained 36% lower fluxes than CW-TILDAS-CS during the first period, including the emission episode, whereas the correspondence with other instruments during the rest of the campaign was good. The reasons for systematic differences were not identified, suggesting further need for detailed evaluation of instrument performance under field conditions with emphasis on stability, calibration and any other factors that can systematically affect the accuracy of flux measurements. The instrument CW-TILDAS-CS was characterized by the lowest noise level (with a standard deviation of around 0.12 ppb at 10 Hz sampling rate) as compared to N2O / CO-23d and QC-TILDAS-76-CS (around 0.50 ppb) and TGA100A (around 2 ppb). We identified that for all instruments except CW-TILDAS-CS the random error due to instrumental noise was an important source of uncertainty at the 30 min averaging level and the total stochastic error was frequently

  19. Microfiltration conditions modify Lactobacillus bulgaricus cryotolerance in response to physiological changes.

    Science.gov (United States)

    Streit, Fernanda; Athès, Violaine; Bchir, Amine; Corrieu, Georges; Béal, Catherine

    2011-02-01

    This work aimed at analyzing the effect of microfiltration conditions (cross-flow velocity and transmembrane pressure) on the quality of frozen Lactobacillus bulgaricus CFL1 starters produced on pilot scale. Microfiltered cells were less resistant during the concentration process than centrifuged cells. In contrast, bacterial cryotolerance during freezing was improved after microfiltration, in a range of 28-88%, depending on the microfiltration conditions. During frozen storage, cell resistance was also affected by microfiltration conditions, either positively or negatively, compared to centrifugation. The best cryotolerance was obtained for cells microfiltered at a cross-flow velocity of 2 m/s and a transmembrane pressure of 0.15 MPa. This improvement was explained by considering membrane fatty acid composition of Lb. bulgaricus CFL1. This condition increased unsaturated to saturated and cyclic to saturated fatty acid ratios, which enhanced membrane fluidity, thus helping the cells to better resist freezing and frozen storage.

  20. Modeling of the effect of freezer conditions on the principal constituent parameters of ice cream by using response surface methodology.

    Science.gov (United States)

    Inoue, K; Ochi, H; Taketsuka, M; Saito, H; Sakurai, K; Ichihashi, N; Iwatsuki, K; Kokubo, S

    2008-05-01

    A systematic analysis was carried out by using response surface methodology to create a quantitative model of the synergistic effects of conditions in a continuous freezer [mix flow rate (L/h), overrun (%), cylinder pressure (kPa), drawing temperature ( degrees C), and dasher speed (rpm)] on the principal constituent parameters of ice cream [rate of fat destabilization (%), mean air cell diameter (mum), and mean ice crystal diameter (mum)]. A central composite face-centered design was used for this study. Thirty-one combinations of the 5 above-mentioned freezer conditions were designed (including replicates at the center point), and ice cream samples were manufactured and examined in a continuous freezer under the selected conditions. The responses were the 3 variables given above. A quadratic model was constructed, with the freezer conditions as the independent variables and the ice cream characteristics as the dependent variables. The coefficients of determination (R(2)) were greater than 0.9 for all 3 responses, but Q(2), the index used here for the capability of the model for predicting future observed values of the responses, was negative for both the mean ice crystal diameter and the mean air cell diameter. Therefore, pruned models were constructed by removing terms that had contributed little to the prediction in the original model and by refitting the regression model. It was demonstrated that these pruned models provided good fits to the data in terms of R(2), Q(2), and ANOVA. The effects of freezer conditions were expressed quantitatively in terms of the 3 responses. The drawing temperature ( degrees C) was found to have a greater effect on ice cream characteristics than any of the other factors.

  1. Thermal processing of bone: in vitro response of mesenchymal cells to bone-conditioned medium.

    Science.gov (United States)

    Sawada, K; Caballé-Serrano, J; Schuldt Filho, G; Bosshardt, D D; Schaller, B; Buser, D; Gruber, R

    2015-08-01

    The autoclaving, pasteurization, and freezing of bone grafts to remove bacteria and viruses, and for preservation, respectively, is considered to alter biological properties during graft consolidation. Fresh bone grafts release paracrine-like signals that are considered to support tissue regeneration. However, the impact of the autoclaving, pasteurization, and freezing of bone grafts on paracrine signals remains unknown. Therefore, conditioned medium was prepared from porcine cortical bone chips that had undergone thermal processing. The biological properties of the bone-conditioned medium were assessed by examining the changes in expression of target genes in oral fibroblasts. The data showed that conditioned medium obtained from bone chips that had undergone pasteurization and freezing changed the expression of adrenomedullin, pentraxin 3, BTB/POZ domain-containing protein 11, interleukin 11, NADPH oxidase 4, and proteoglycan 4 by at least five-fold in oral fibroblasts. Bone-conditioned medium obtained from autoclaved bone chips, however, failed to change the expression of the respective genes. Also, when bone-conditioned medium was prepared from fresh bone chips, autoclaving blocked the capacity of bone-conditioned medium to modulate gene expression. These in vitro results suggest that pasteurization and freezing of bone grafts preserve the release of biologically active paracrine signals, but autoclaving does not. Copyright © 2015 International Association of Oral and Maxillofacial Surgeons. Published by Elsevier Ltd. All rights reserved.

  2. Acute alcohol impairs conditioning of a behavioural reward-seeking response and inhibitory control processes--implications for addictive disorders.

    Science.gov (United States)

    Loeber, Sabine; Duka, Theodora

    2009-12-01

    To investigate whether acute alcohol would affect performance of a conditioned behavioural response to obtain a reward outcome and impair performance in a task measuring inhibitory control to provide new knowledge of how the acute effects of alcohol might contribute to the transition from alcohol use to dependence. A randomized controlled between-subjects design was employed. The laboratory of experimental psychology at the University of Sussex. Thirty-two light to moderate social drinkers recruited from the undergraduate and postgraduate population. After the administration of alcohol (0.8 g/kg) or placebo participants underwent an instrumental reward-seeking procedure, with abstract stimuli serving as S+ (always predicting a win of 10 pence) and S- (always predicting a loss of 10 pence). In addition, a Stop Signal task was administered before and after the administration of alcohol. Participants of the alcohol group performed the behavioural response to obtain the reward outcome more often than placebo subjects in trials associated with loss of money. This finding was observed, although alcohol was not affecting explicit knowledge of stimulus-response outcome contingencies and acquisition of conditioned attentional and emotional responses. In addition, alcohol increased Stop Signal reaction time indicating disinhibiting effects of alcohol, and this was associated positively with response probability to the S-. These results demonstrate that alcohol is affecting inhibitory control of behavioural responses to external signals even when associated with punishment, contributing in this way to the transition from alcohol use to dependence.

  3. Drug–drug conditioning between citalopram and haloperidol or olanzapine in a conditioned avoidance response model: implications for polypharmacy in schizophrenia

    Science.gov (United States)

    Sparkman, Nathan L.; Li, Ming

    2016-01-01

    Patients with schizophrenia often have anxiety and depression, and thus are treated with multiple psychotherapeutic medications. This practice of polypharmacy increases the possibility for drug–drug interactions. However, the pharmacological and behavioral mechanisms underlying drug–drug interactions in schizophrenia remain poorly understood. In the present study, we adopted a preclinical approach and examined a less known behavioral mechanism, drug–drug conditioning (DDC) between haloperidol (a typical antipsychotic) or olanzapine (atypical antipsychotic) and citalopram (a selective serotonin reuptake inhibitor). A rat two-way conditioned avoidance response paradigm was used to measure antipsychotic activity and determine how DDC may alter the antipsychotic efficacy in this model. Following acquisition of the avoidance response, rats were then randomly assigned to receive vehicle, citalopram (10.0 mg/kg, intraperitoneally), haloperidol (0.05 mg/kg, subcutaneously), olanzapine (1.0 mg/kg, subcutaneously), combined haloperidol with citalopram, or combined olanzapine with citalopram treatment for seven avoidance test sessions. In comparison with antipsychotic treatment alone, combined treatment with citalopram potentiated the antiavoidance effect of olanzapine or haloperidol (to a lesser extent) during the seven drug-test sessions. In addition, repeated pairing of citalopram with haloperidol or olanzapine caused citalopram to show a newly acquired avoidance-disruptive effect. This effect was context specific because citalopram paired with haloperidol or olanzapine outside the avoidance testing context (i.e. home cages) did not show such an effect. These findings indicate that concurrent antidepressant and antipsychotic treatments may engender a DDC process that follows the general Pavlovian associative conditioning principles. They also indicate that adjunctive citalopram treatment may enhance the antipsychotic efficacy of haloperidol and olanzapine in the

  4. Earthworm responses to Cd and Cu under fluctuating environmental conditions: a comparison with results from laboratory exposures

    International Nuclear Information System (INIS)

    Spurgeon, David J.; Svendsen, Claus; Lister, Lindsay J.; Hankard, Peter K.; Kille, Peter

    2005-01-01

    Laboratory toxicity tests are usually conducted under stable ambient conditions, while exposures in ecosystems occur in a fluctuating climate. To assess how climate influences the toxicity of Cu and Cd for the earthworm Lumbricus rubellus, this study compared effects for life-cycle parameters (survival, reproduction), cellular status (lysosomal membrane stability), gene expression (transcript of the metal binding protein metallothionein-2) and tissue metal concentration measured under outdoor conditions, with the same responses under constant conditions as measured by Spurgeon et al. [Spurgeon, D.J., Svendsen, C., Weeks, J.M., Hankard, P.K., Stubberud, H.E., Kammenga, J.E., 2003. Quantifying copper and cadmium impacts on intrinsic rate of population increase in the terrestrial oligochaete Lumbricus rubellus. Environmental Toxicology and Chemistry 22, 1465-1472]. Both metals were found to significantly influence earthworm reproduction, compromise lysosomal membrane stability and induce MT-2 gene expression in the outdoor system. Comparison with physiological and life-cycle responses in the laboratory indicated similar response patterns and effect concentrations for Cu. For Cd, lysosomal membrane stability and MT-2expression showed comparable responses in both exposures. Juvenile production rate, however, gave different dose response relationships, with the EC- 50 in the outdoor test approximately half that in the laboratory test. A difference in Cd accumulation was also seen. Overall, however, the comparison indicated only a marginal effect of environmental fluctuations typical for northern temperate Europe on earthworm sensitivity to the two metals. - Comparative analysis of life-cycle, physiological and molecular responses to Cu and Cd indicate similar responses under static and fluctuating climate regimes

  5. Impact Analysis of Temperature and Humidity Conditions on Electrochemical Sensor Response in Ambient Air Quality Monitoring.

    Science.gov (United States)

    Wei, Peng; Ning, Zhi; Ye, Sheng; Sun, Li; Yang, Fenhuan; Wong, Ka Chun; Westerdahl, Dane; Louie, Peter K K

    2018-01-23

    The increasing applications of low-cost air sensors promises more convenient and cost-effective systems for air monitoring in many places and under many conditions. However, the data quality from such systems has not been fully characterized and may not meet user expectations in research and regulatory uses, or for use in citizen science. In our study, electrochemical sensors (Alphasense B4 series) for carbon monoxide (CO), nitric oxide (NO), nitrogen dioxide (NO₂), and oxidants (O x ) were evaluated under controlled laboratory conditions to identify the influencing factors and quantify their relation with sensor outputs. Based on the laboratory tests, we developed different correction methods to compensate for the impact of ambient conditions. Further, the sensors were assembled into a monitoring system and tested in ambient conditions in Hong Kong side-by-side with regulatory reference monitors, and data from these tests were used to evaluate the performance of the models, to refine them, and validate their applicability in variable ambient conditions in the field. The more comprehensive correction models demonstrated enhanced performance when compared with uncorrected data. One over-arching observation of this study is that the low-cost sensors may promise excellent sensitivity and performance, but it is essential for users to understand and account for several key factors that may strongly affect the nature of sensor data. In this paper, we also evaluated factors of multi-month stability, temperature, and humidity, and considered the interaction of oxidant gases NO₂ and ozone on a newly introduced oxidant sensor.

  6. Effects of baseline conditions on the simulated hydrologic response to projected climate change

    Science.gov (United States)

    Koczot, Kathryn M.; Markstrom, Steven L.; Hay, Lauren E.

    2011-01-01

    Changes in temperature and precipitation projected from five general circulation models, using one late-twentieth-century and three twenty-first-century emission scenarios, were downscaled to three different baseline conditions. Baseline conditions are periods of measured temperature and precipitation data selected to represent twentieth-century climate. The hydrologic effects of the climate projections are evaluated using the Precipitation-Runoff Modeling System (PRMS), which is a watershed hydrology simulation model. The Almanor Catchment in the North Fork of the Feather River basin, California, is used as a case study. Differences and similarities between PRMS simulations of hydrologic components (i.e., snowpack formation and melt, evapotranspiration, and streamflow) are examined, and results indicate that the selection of a specific time period used for baseline conditions has a substantial effect on some, but not all, hydrologic variables. This effect seems to be amplified in hydrologic variables, which accumulate over time, such as soil-moisture content. Results also indicate that uncertainty related to the selection of baseline conditions should be evaluated using a range of different baseline conditions. This is particularly important for studies in basins with highly variable climate, such as the Almanor Catchment.

  7. Airfoil wake and linear theory gust response including sub and superresonant flow conditions

    Science.gov (United States)

    Henderson, Gregory H.; Fleeter, Sanford

    1992-01-01

    The unsteady aerodynamic gust response of a high solidity stator vane row is examined in terms of the fundamental gust modeling assumptions with particular attention given to the effects near an acoustic resonance. A series of experiments was performed with gusts generated by rotors comprised of perforated plates and airfoils. It is concluded that, for both the perforated plate and airfoil wake generated gusts, the unsteady pressure responses do not agree with the linear-theory gust predictions near an acoustic resonance. The effects of the acoustic resonance phenomena are clearly evident on the airfoil surface unsteady pressure responses. The transition of the measured lift coefficients across the acoustic resonance from the subresonant regime to the superresonant regime occurs in a simple linear fashion.

  8. Contingency awareness shapes acquisition and extinction of emotional responses in a conditioning model of pain-related fear

    Directory of Open Access Journals (Sweden)

    Franziska eLabrenz

    2015-11-01

    Full Text Available As a fundamental learning process, fear conditioning promotes the formation of associations between predictive cues and biologically-significant signals. In its application to pain, conditioning may provide important insight into mechanisms underlying pain-related fear, although knowledge especially in interoceptive pain paradigms remains scarce. Furthermore, while the influence of contingency awareness on excitatory learning is subject of ongoing debate, its role in pain-related acquisition is poorly understood and essentially unknown regarding extinction as inhibitory learning. Therefore, we addressed the impact of contingency awareness on learned emotional responses to pain- and safety-predictive cues in a combined dataset of two pain-related conditioning studies.In total, 75 healthy participants underwent differential fear acquisition, during which rectal distensions as interoceptive unconditioned stimuli (US were repeatedly paired with a predictive visual cue (conditioned stimulus; CS+ while another cue (CS- was presented unpaired. During extinction, both CS were presented without US. CS valence, indicating learned emotional responses, and CS-US contingencies were assessed on visual analogue scales. Based on an integrative measure of contingency accuracy, a median-split was performed to compare groups with low versus high contingency accuracy regarding learned emotional responses. To investigate predictive value of contingency accuracy, regression analyses were conducted. Highly accurate individuals revealed more pronounced negative emotional responses to CS+ and increased positive responses to CS- when compared to participants with low contingency accuracy. Following extinction, highly accurate individuals had fully extinguished pain-predictive cue properties, while exhibiting persistent positive emotional responses to safety signals. In contrast, individuals with low accuracy revealed equally positive emotional responses to both, CS+ and

  9. Contingency Awareness Shapes Acquisition and Extinction of Emotional Responses in a Conditioning Model of Pain-Related Fear.

    Science.gov (United States)

    Labrenz, Franziska; Icenhour, Adriane; Benson, Sven; Elsenbruch, Sigrid

    2015-01-01

    As a fundamental learning process, fear conditioning promotes the formation of associations between predictive cues and biologically significant signals. In its application to pain, conditioning may provide important insight into mechanisms underlying pain-related fear, although knowledge especially in interoceptive pain paradigms remains scarce. Furthermore, while the influence of contingency awareness on excitatory learning is subject of ongoing debate, its role in pain-related acquisition is poorly understood and essentially unknown regarding extinction as inhibitory learning. Therefore, we addressed the impact of contingency awareness on learned emotional responses to pain- and safety-predictive cues in a combined dataset of two pain-related conditioning studies. In total, 75 healthy participants underwent differential fear acquisition, during which rectal distensions as interoceptive unconditioned stimuli (US) were repeatedly paired with a predictive visual cue (conditioned stimulus; CS(+)) while another cue (CS(-)) was presented unpaired. During extinction, both CS were presented without US. CS valence, indicating learned emotional responses, and CS-US contingencies were assessed on visual analog scales (VAS). Based on an integrative measure of contingency accuracy, a median-split was performed to compare groups with low vs. high contingency accuracy regarding learned emotional responses. To investigate predictive value of contingency accuracy, regression analyses were conducted. Highly accurate individuals revealed more pronounced negative emotional responses to CS(+) and increased positive responses to CS(-) when compared to participants with low contingency accuracy. Following extinction, highly accurate individuals had fully extinguished pain-predictive cue properties, while exhibiting persistent positive emotional responses to safety signals. In contrast, individuals with low accuracy revealed equally positive emotional responses to both, CS(+) and CS

  10. Radiation-use efficiency in maize: response to fertilization and meteorological conditions

    International Nuclear Information System (INIS)

    Mikova, A.; Dimitrov, I.; Stoyanov, P.

    2005-01-01

    The effect of fertilization rates on radiation use efficiency (RUE) of maize was examined. The investigations were carried out in Sadovo Experimental station on the leached vertisol. Two years with different growing periods in terms of meteorological conditions were chosen. The RUE by organs and for the whole plant for each phenological phase of maize development was estimated. It was found that the highest RUE in conditions of low air temperature and high air humidity during the first stages of growing period (vegetative growth) are observed in maize grown at 125% of fertilization rate. In conditions of high air temperature and low air humidity during the same stages, the plants, grown at 50% of fertilization rate, utilization of mineral fertilization are more successfully

  11. The deviatoric response of three dense glasses under shock loading conditions

    International Nuclear Information System (INIS)

    Radford, D.D.; Proud, W.G.; Field, J.E.

    2002-01-01

    In-material longitudinal and lateral stress histories in three dense, silica-based glasses were directly measured by embedded manganin stress gauges during plate impact experiments. Lateral stress profiles in all of the materials show evidence of failure fronts that behave in a similar manner to those observed in open-structured glasses. The measured stress histories were used to calculate the deviatoric responses and results indicate that ahead of the failure front the shear stress increases linearly along the estimated elastic response. Behind the failure front, however, the shear stress appears to first decrease and then increase as the pressure increases, contrary to a previous interpretation

  12. Analysis of railcar-shipping container system response to impact conditions

    International Nuclear Information System (INIS)

    Bartholomew, R.J.; Butler, T.A.

    1980-01-01

    An existing mathematical model for simulating railcar-container system response to coupling impacts was revised to simulate configurations that were tested in full-scale experiments. The structural model is represented with the lumped-parameter technique. The resulting equations are linear except for those for the coupler forces experienced during the impact. Results from the mathematical model are compared with load and acceleration data obtained during the full-scale tests. The model predicts actual response accurately enough to make it useful as a design and safety analysis tool

  13. Herbivore body condition response in altered environments: mule deer and habitat management.

    Directory of Open Access Journals (Sweden)

    Eric J Bergman

    Full Text Available The relationships between habitat, body condition, life history characteristics, and fitness components of ungulates are interwoven and of interest to researchers as they strive to understand the impacts of a changing environment. With the increased availability of portable ultrasound machines and the refinement of hormonal assays, assessment of ungulate body condition has become an accessible monitoring strategy. We employed body condition scoring, estimation of % ingesta-free body fat (%IFBF, assessment of free thyroid hormones (FT4 and FT3, and assessment of pregnancy, as metrics to determine if landscape-level habitat treatments affected body condition of adult (≥ 1.5 years old female mule deer (Odocoileus hemionus. All body condition related metrics were measured on 2 neighboring study areas--a reference area that had received no habitat treatments and a treatment study area that had received mechanical removal of pinyon pine (Pinyus edulis--Utah juniper (Juniperus osteosperma forest, chemical control of weeds, and reseeding with preferred mule deer browse species. A consistent trend of higher %IFBF was observed in the treatment study area [Formula: see text] than in the reference study area [Formula: see text], although variation of estimates was larger than hypothesized. A similar pattern was observed with higher thyroid hormones concentrations being observed in the treatment study area, but large amounts of variation within concentration estimates were also observed. The consistent pattern of higher body condition related estimates in our treatment study area provides evidence that large mammalian species are sensitive to landscape change, although variation within estimates underlie the challenge in detecting population level impacts stemming from environmental change.

  14. Optimisation of Ultrasound-Assisted Extraction Conditions for Phenolic Content and Antioxidant Capacity from Euphorbia tirucalli Using Response Surface Methodology

    Science.gov (United States)

    Vuong, Quan V.; Goldsmith, Chloe D.; Dang, Trung Thanh; Nguyen, Van Tang; Bhuyan, Deep Jyoti; Sadeqzadeh, Elham; Scarlett, Christopher J.; Bowyer, Michael C.

    2014-01-01

    Euphorbia tirucalli (E. tirucalli) is now widely distributed around the world and is well known as a source of traditional medicine in many countries. This study aimed to utilise response surface methodology (RSM) to optimise ultrasonic-assisted extraction (UAE) conditions for total phenolic compounds (TPC) and antioxidant capacity from E. tirucalli leaf. The results showed that ultrasonic temperature, time and power effected TPC and antioxidant capacity; however, the effects varied. Ultrasonic power had the strongest influence on TPC; whereas ultrasonic temperature had the greatest impact on antioxidant capacity. Ultrasonic time had the least impact on both TPC and antioxidant capacity. The optimum UAE conditions were determined to be 50 °C, 90 min. and 200 W. Under these conditions, the E. tirucalli leaf extract yielded 2.93 mg GAE/g FW of TPC and exhibited potent antioxidant capacity. These conditions can be utilised for further isolation and purification of phenolic compounds from E. tirucalli leaf. PMID:26785074

  15. Dynamic characteristics and structural response of the SWR 1000 under earthquake loading conditions

    International Nuclear Information System (INIS)

    Bielor, E.; Brettschuh, W.; Krutzik, N.J.; Tropp, R.

    2001-01-01

    Based on the conceptual design documentation of the SWR 1000 reactor building as well as specified representative seismological, and soil-dynamic input data, corresponding to prospective sites as a basis, the dynamic characteristics, as well as the in-structure dynamic response of the coupled vibrating structures have been elaborated. The structural design analysis was based on a 3-dimensional mathematical model of the building in which all details of the internal structures as well as the containment including the water in the pools were represented adequately. In order to demonstrate the influence of the soil-structure interaction effects on the dynamic response results, the soil was represented by two different assumptions. At first, considering the state of the art procedures, assuming frequency independent soil capabilities (equivalent stiffnesses and damping values), time domain calculations were carried out. In the second step, based on the frequency-dependency of the soil capabilities, frequency domain calculations were performed. The structural responses obtained by means of both procedures and the same mathematical model of the structures were evaluated and compared. The suitability of the preliminary design concept are discussed and the structural response results obtained on the basis of the bearing capacity and the stresses in the characteristic regions of the structure

  16. Variation in stonefly (Nemoura cinerea Retzius) growth and development in response to hydraulic and substrate conditions

    NARCIS (Netherlands)

    Franken, R.J.M.; Gardeniers, J.J.P.; Beijer, J.A.J.; Peeters, E.T.H.M.

    2008-01-01

    Spatial heterogeneity among microhabitat patches in aquatic ecosystems creates refuges (e.g., substrate interstices) that protect organisms against a variety of environmental constraints. Aquatic insects have evolved the ability to alter their life-history traits in response to environmental

  17. Dynamic preload indicators fail to predict fluid responsiveness in open-chest conditions

    NARCIS (Netherlands)

    de Waal, Eric E. C.; Rex, Steffen; Kruitwagen, Cas L. J. J.; Kalkman, Cor J.; Buhre, Wolfgang F.

    Objective: Dynamic preload indicators like pulse pressure variation (PPV) and stroke volume variation (SVV) are increasingly being used for optimizing cardiac preload since they have been demonstrated to predict fluid responsiveness in a variety of perioperative settings. However, in open-chest

  18. Sustainable Ergonomic Program - Basic Condition for Implementation of Corporate Social Responsibility

    Science.gov (United States)

    Marková, Petra; Beňo, Rastislav; Hatiar, Karol

    2012-12-01

    Gradually increasing pressure on companies to start to behave socially responsible is a response to social, environmental and economic requirements. The society faces a period of changes that have occurred since the beginning of the crisis and revealing weaknesses in the economy. We become witnesses of rapid changes and challenges posed by globalization, lack of resources, demographic structure and innovation. Objective necessity becomes a corporate social responsibility (CSR) already at the companies’ level, which is supported by the approach of the EU institutions and the Slovak Republic. One of the possible appliance through which we can contribute to the sustainability of CSR are sustainable ergonomic programs. When we want to talk about sustainable ergonomic program is important to focus on three key areas. The first area is the Impact of technic and technology to employees at work, the second area is the Importance and impact of socially responsible HR in ergonomics and last area is the Creation of the work environment in relation to environmental sustainability. Ergonomic programs sustainability requires to apply appropriate methods for evaluation of their cost benefit and health effect.

  19. Protection and conservation of tourism potential. Essential conditions for a sustainable and responsible development of tourism.

    OpenAIRE

    Nicolae Neacsu

    2012-01-01

    Tourism is considered a rapidly growing phenomenon and it has become one of the largest industries in the world and its impact is extremely varied. This paper presents the many aspects of responsible tourism considering the importance of this approach for the economic and social development

  20. Response of the photosynthetic system to altered protein composition and changes in environmental conditions

    NARCIS (Netherlands)

    Tóth, T.

    2014-01-01

    The photosynthetic thylakoid membrane has a hierarchically ordered structure containing pigment-protein complexes that capture solar radiation and convert it into chemical energy. Its highly dynamic structure is capable to continuously respond to the altered environmental conditions, e.g., light

  1. Enzymatic scavenging of oxygen dissolved in water: Application of response surface methodology in optimization of conditions

    Directory of Open Access Journals (Sweden)

    Karimi Afzal

    2012-01-01

    Full Text Available In this work, removal of dissolved oxygen in water through reduction by glucose, which was catalyzed by glucose oxidase – catalase enzyme, was studied. Central composite design (CCD technique was applied to achieve optimum conditions for dissolved oxygen scavenging. Linear, square and interactions between effective parameters were obtained to develop a second order polynomial equation. The adequacy of the obtained model was evaluated by the residual plots, probability-value, coefficient of determination, and Fisher’s variance ratio test. Optimum conditions for activity of two enzymes in water deoxygenation were obtained as follows: pH=5.6, T=40°C, initial substrate concentration [S] = 65.5 mmol/L and glucose oxidase activity [E] = 252 U/Lat excess amount of catalase. The deoxygenation process during 30 seconds, in the optimal conditions, was predicted 98.2%. Practical deoxygenation in the predicted conditions was achieved to be 95.20% which was close to the model prediction.

  2. Measurement of forest condition and response along the Pennsylvania atmospheric deposition gradent

    Science.gov (United States)

    D.D. David; J.M. Skelly; J.A. Lynch; L.H. McCormick; B.L. Nash; M. Simini; E.A. Cameron; J.R. McClenahen; R.P. Long

    1991-01-01

    Research in the oak-hickory forest of northcentral Pennsylvania is being conducted to detect anomalies in forest condition that may be due to atmospheric deposition, with the intent that such anomalies will be further studied to determine the role, if any, of atmospheric deposition. This paper presents the status of research along a 160-km gradient of sulfate/nitrate...

  3. Response of rice cultivars to rates of nitrogen and potassium application in field and pot conditions.

    Science.gov (United States)

    Bahmaniar, M A; Ranjbar, G A

    2007-05-01

    Nitrogen and potassium are the yield-limiting nutrients in rice production regions of Iran. Use of N and K efficient cultivars is an important complementary strategy in improving rice yield, increasing the quality properties of rice grains and reducing cost of production. In order to consider the effects of different amounts of N and K application on rice (Oryza sativa L.) yield and yield components in pot and field conditions these experiments were undertaken in 2004 at Sari Agricultural Station, Iran. Four levels of N (0, 50, 100 and 150 Kg N ha(-1) in field and 0, 0.6, 1.2 and 1.8 g N pot(-1) in pot) corresponding with four levels of K (0, 75, 150 and 225 kg K2O ha(-1) in field and 0, 0.5, 1 and 1.5 g K2O pot(-1) in pot) were applied in a split-factorial plot design with three replications in both pot and field experiments, variously. Grain yield, number of grain per panicle, number of tiller, plant height, length of flag leaf, total and shoot dry matter, 1000 grain weight and harvest index have been increased by N application in field conditions. However, in pot conditions grain yield, number of grain per panicle, number of tiller, plant height, width of flag leaf, total and shoot dry matter, leaf nitrogen contents and harvest index have significantly been increased (p pot conditions (p < or = 0.05).

  4. The impact of weather conditions on response of sorghum genotypes to anthracnose (Colletotrichum sublineola) infection

    Science.gov (United States)

    Rainfall is a major climatic factor influencing anthracnose development and in this study, 68 sorghum accessions were evaluated for anthracnose resistance under dry and wet growing conditions at the Texas A&M Agricultural Experiment Station, near College Station, Texas. Accessions, planted in a ran...

  5. HIF-1α-induced HSP70 regulates anabolic responses in articular chondrocytes under hypoxic conditions.

    Science.gov (United States)

    Tsuchida, Shinji; Arai, Yuji; Takahashi, Kenji A; Kishida, Tsunao; Terauchi, Ryu; Honjo, Kuniaki; Nakagawa, Shuji; Inoue, Hiroaki; Ikoma, Kazuya; Ueshima, Keiichiro; Matsuki, Tomohiro; Mazda, Osam; Kubo, Toshikazu

    2014-08-01

    We assessed whether heat shock protein 70 (HSP70) is involved in hypoxia inducible factor 1 alpha (HIF-1α)-dependent anabolic pathways in articular chondrocytes under hypoxic conditions. Primary rabbit chondrocytes were cultured under normoxia (20% oxygen condition) or hypoxia (1% oxygen condition). Alternatively, cells cultured under normoxia were treated with CoCl2 , which induces HIF-1α, to simulate hypoxia, or transfected with siRNAs targeting HIF-1α (si-HIF-1α) and HSP70 (si-HSP70) under hypoxia. HSP70 expression was enhanced by the increased expression of HIF-1α under hypoxia or simulated hypoxia, but not in the presence of si-HIF-1α. Hypoxia-induced overexpression of ECM genes was significantly suppressed by si-HIF-1α or si-HSP70. Cell viability positively correlated with hypoxia, but transfection with si-HIF-1α or si-HSP70 abrogated the chondroprotective effects of hypoxia. Although LDH release from sodium nitroprusside-treated cells and the proportion of TUNEL positive cells were decreased under hypoxia, transfection with si-HIF-1α or si-HSP70 almost completely blocked these effects. These findings indicated that HIF-1α-induced HSP70 overexpression increased the expression levels of ECM genes and cell viability, and protected chondrocytes from apoptosis. HIF-1α may regulate the anabolic effects of chondrocytes under hypoxic conditions by regulating HSP70 expression. © 2014 Orthopaedic Research Society. Published by Wiley Periodicals, Inc.

  6. Impact Analysis of Temperature and Humidity Conditions on Electrochemical Sensor Response in Ambient Air Quality Monitoring

    Directory of Open Access Journals (Sweden)

    Peng Wei

    2018-01-01

    Full Text Available The increasing applications of low-cost air sensors promises more convenient and cost-effective systems for air monitoring in many places and under many conditions. However, the data quality from such systems has not been fully characterized and may not meet user expectations in research and regulatory uses, or for use in citizen science. In our study, electrochemical sensors (Alphasense B4 series for carbon monoxide (CO, nitric oxide (NO, nitrogen dioxide (NO2, and oxidants (Ox were evaluated under controlled laboratory conditions to identify the influencing factors and quantify their relation with sensor outputs. Based on the laboratory tests, we developed different correction methods to compensate for the impact of ambient conditions. Further, the sensors were assembled into a monitoring system and tested in ambient conditions in Hong Kong side-by-side with regulatory reference monitors, and data from these tests were used to evaluate the performance of the models, to refine them, and validate their applicability in variable ambient conditions in the field. The more comprehensive correction models demonstrated enhanced performance when compared with uncorrected data. One over-arching observation of this study is that the low-cost sensors may promise excellent sensitivity and performance, but it is essential for users to understand and account for several key factors that may strongly affect the nature of sensor data. In this paper, we also evaluated factors of multi-month stability, temperature, and humidity, and considered the interaction of oxidant gases NO2 and ozone on a newly introduced oxidant sensor.

  7. Impact Analysis of Temperature and Humidity Conditions on Electrochemical Sensor Response in Ambient Air Quality Monitoring

    Science.gov (United States)

    Ning, Zhi; Ye, Sheng; Sun, Li; Yang, Fenhuan; Wong, Ka Chun; Westerdahl, Dane; Louie, Peter K. K.

    2018-01-01

    The increasing applications of low-cost air sensors promises more convenient and cost-effective systems for air monitoring in many places and under many conditions. However, the data quality from such systems has not been fully characterized and may not meet user expectations in research and regulatory uses, or for use in citizen science. In our study, electrochemical sensors (Alphasense B4 series) for carbon monoxide (CO), nitric oxide (NO), nitrogen dioxide (NO2), and oxidants (Ox) were evaluated under controlled laboratory conditions to identify the influencing factors and quantify their relation with sensor outputs. Based on the laboratory tests, we developed different correction methods to compensate for the impact of ambient conditions. Further, the sensors were assembled into a monitoring system and tested in ambient conditions in Hong Kong side-by-side with regulatory reference monitors, and data from these tests were used to evaluate the performance of the models, to refine them, and validate their applicability in variable ambient conditions in the field. The more comprehensive correction models demonstrated enhanced performance when compared with uncorrected data. One over-arching observation of this study is that the low-cost sensors may promise excellent sensitivity and performance, but it is essential for users to understand and account for several key factors that may strongly affect the nature of sensor data. In this paper, we also evaluated factors of multi-month stability, temperature, and humidity, and considered the interaction of oxidant gases NO2 and ozone on a newly introduced oxidant sensor. PMID:29360749

  8. Groundwater decline and tree change in floodplain landscapes: Identifying non-linear threshold responses in canopy condition

    Directory of Open Access Journals (Sweden)

    J. Kath

    2014-12-01

    Full Text Available Groundwater decline is widespread, yet its implications for natural systems are poorly understood. Previous research has revealed links between groundwater depth and tree condition; however, critical thresholds which might indicate ecological ‘tipping points’ associated with rapid and potentially irreversible change have been difficult to quantify. This study collated data for two dominant floodplain species, Eucalyptus camaldulensis (river red gum and E. populnea (poplar box from 118 sites in eastern Australia where significant groundwater decline has occurred. Boosted regression trees, quantile regression and Threshold Indicator Taxa Analysis were used to investigate the relationship between tree condition and groundwater depth. Distinct non-linear responses were found, with groundwater depth thresholds identified in the range from 12.1 m to 22.6 m for E. camaldulensis and 12.6 m to 26.6 m for E. populnea beyond which canopy condition declined abruptly. Non-linear threshold responses in canopy condition in these species may be linked to rooting depth, with chronic groundwater decline decoupling trees from deep soil moisture resources. The quantification of groundwater depth thresholds is likely to be critical for management aimed at conserving groundwater dependent biodiversity. Identifying thresholds will be important in regions where water extraction and drying climates may contribute to further groundwater decline. Keywords: Canopy condition, Dieback, Drought, Tipping point, Ecological threshold, Groundwater dependent ecosystems

  9. Optimization on Preparation Condition of Propolis Flavonoids Liposome by Response Surface Methodology and Research of Its Immunoenhancement Activity

    Directory of Open Access Journals (Sweden)

    Ju Yuan

    2013-01-01

    Full Text Available The aim of this study is to prepare propolis flavonoids liposome (PFL and optimize the preparation condition and to investigate further whether liposome could promote the immunoenhancement activity of propolis flavonoids (PF. PFL was prepared with ethanol injection method, and the preparation conditions of PFL were optimized with response surface methodology (RSM. Moreover, the immunoenhancement activity of PFL and PF in vitro was determined. The result showed that the optimal preparation conditions for PFL by response surface methodology were as follows: ratio of lipid to drug (w/w 9.6 : 1, ratio of soybean phospholipid to cholesterol (w/w 8.5 : 1, and speed of injection 0.8 mL·min−1. Under these conditions, the experimental encapsulation efficiency of PFL was 91.67 ± 0.21%, which was close to the predicted value. Therefore, the optimized preparation condition is very reliable. Moreover, the results indicated that PFL could not only significantly promote lymphocytes proliferation singly or synergistically with PHA, but also increase expression level of IL-2 and IFN-γ mRNA. These indicated that liposome could significantly improve the immunoenhancement activity of PF. PFL demonstrates the significant immunoenhancement activity, which provides the theoretical basis for the further experiment in vivo.

  10. [Optimization of prokaryotic expression conditions of Leptospira interrogans trigeminy genus-specific protein antigen based on surface response analysis].

    Science.gov (United States)

    Wang, Jiang; Luo, Dongjiao; Sun, Aihua; Yan, Jie

    2008-07-01

    Lipoproteins LipL32 and LipL21 and transmembrane protein OMPL1 have been confirmed as the superficial genus-specific antigens of Leptospira interrogans, which can be used as antigens for developing a universal genetic engineering vaccine. In order to obtain high expression of an artificial fusion gene lipL32/1-lipL21-ompL1/2, we optimized prokaryotic expression conditions. We used surface response analysis based on the central composite design to optimize culture conditions of a new antigen protein by recombinant Escherichia coli DE3.The culture conditions included initial pH, induction start time, post-induction time, Isopropyl beta-D-thiogalactopyranoside (IPTG) concentration, and temperature. The maximal production of antigen protein was 37.78 mg/l. The optimal culture conditions for high recombinant fusion protein was determined: initial pH 7.9, induction start time 2.5 h, a post-induction time of 5.38 h, 0.20 mM IPTG, and a post-induction temperature of 31 degrees C. Surface response analysis based on CCD increased the target production. This statistical method reduced the number of experiments required for optimization and enabled rapid identification and integration of the key culture condition parameters for optimizing recombinant protein expression.

  11. Humans, Fish, and Whales: How Right Whales Modify Calling Behavior in Response to Shifting Background Noise Conditions.

    Science.gov (United States)

    Parks, Susan E; Groch, Karina; Flores, Paulo; Sousa-Lima, Renata; Urazghildiiev, Ildar R

    2016-01-01

    This study investigates the role of behavioral plasticity in the variation of sound production of southern right whales (Eubalaena australis) in response to changes in the ambient background noise conditions. Data were collected from southern right whales in Brazilian waters in October and November 2011. The goal of this study was to quantify differences in right whale vocalizations recorded in low background noise as a control, fish chorus noise, and vessel noise. Variation in call parameters were detected among the three background noise conditions and have implications for future studies of noise effects on whale sound production.

  12. Examination of the damage and failure response of tantalum and copper under varied shock loading conditions

    Energy Technology Data Exchange (ETDEWEB)

    Bronkhorst, Curt A [Los Alamos National Laboratory; Dennis - Koller, Darcie [Los Alamos National Laboratory; Cerreta, Ellen K [Los Alamos National Laboratory; Gray Ill, George T [Los Alamos National Laboratory; Bourne, Neil [AWE-ALDERMASTON

    2010-12-16

    A number of plate impact experiments have been conducted on high purity polycrystalline tantalum and copper samples using graded flyer plate configurations to alter the loading profile. These experiments are designed in a way so that a broad range of damage regimes are probed. The results show that the nucleation of damage primarily occurs at the grain boundaries of the materials. This affords us the opportunity to propose a porosity damage nucleation criterion which begins to account for the length scales of the microstructure (grain size distribution) and the mechanical response of the grain boundary regions (failure stress distribution). This is done in the context of a G-T-N type model for the ductile damage and failure response of both the materials examined. The role of micro-inertial effects on the porosity growth process is also considered.

  13. Intelligent Commercial Lighting: Demand-Responsive Conditioning and Increased User Satisfaction

    OpenAIRE

    Agogino, Alice M.

    2005-01-01

    Energy efficiency has recently come to the forefront of energy debates, especially in the state of California. This focus on efficiency has been driven by the deregulation of electrical-energy distribution, the increasing price of electricity, and the implementation of rolling blackouts. Currently, buildings consume over 1/3 of primary energy, and 2/3 of all electricity produced in the U.S. Commercial buildings consume roughly half of this, and lighting is responsible for approximately 40% of...

  14. Effects of Housing Conditions on Stress Responses, Feeding, and Drinking in Male and Female Rats

    Science.gov (United States)

    1995-02-07

    and biochemical changes indicative of a stress response (Singh, D’Souza, & Singh, 1991 ; Peng, Lang, Drozdowicz, & Ohlsson-Wilhelm, 1989; Armario ...immunological, and biochemical changes indicative of stress (Peng et aI., 1989; Armario et aI. , 1987; Gamallo et aI. , 1986; Armario , Ortiz...et aI. , 19~9; Armario et aI. , 1987; Gamallo et aI. , 1986; Calhoun, 1962). Hypothesis 2. It was hypothesized that male rats would decrease food

  15. Pre-crisis Conditions and Government Policy Responses: Chile and Mexico during the Great Recession

    OpenAIRE

    Bruno Martorano

    2014-01-01

    Chile and Mexico reacted to the crisis by implementing several policy responses, they achieved different outcomes. In particular, the Chilean economy recovered faster than the Mexican one. However, the main differences are related to social outcomes. On one hand, the Gini coefficient decreased in both countries. On the other hand, both overall and child poverty dropped in Chile while they rose sharply in Mexico. , Chile introduced a stimulus package twice as large the Mexican one. When the fi...

  16. Conditioned place preference and locomotor activity in response to methylphenidate, amphetamine and cocaine in mice lacking dopamine D4 receptors

    Energy Technology Data Exchange (ETDEWEB)

    Thanos, P.K.; Thanos, P.K.; Bermeo, C.; Rubinstein, M.; Suchland, K.L.; Wang, G.-J.; Grandy, D.K.; Volkow, N.D.

    2010-05-01

    Methylphenidate (MP) and amphetamine (AMPH) are the most frequently prescribed medications for the treatment of attention-deficit/hyperactivity disorder (ADHD). Both drugs are believed to derive their therapeutic benefit by virtue of their dopamine (DA)-enhancing effects, yet an explanation for the observation that some patients with ADHD respond well to one medication but not to the other remains elusive. The dopaminergic effects of MP and AMPH are also thought to underlie their reinforcing properties and ultimately their abuse. Polymorphisms in the human gene that codes for the DA D4 receptor (D4R) have been repeatedly associated with ADHD and may correlate with the therapeutic as well as the reinforcing effects of responses to these psychostimulant medications. Conditioned place preference (CPP) for MP, AMPH and cocaine were evaluated in wild-type (WT) mice and their genetically engineered littermates, congenic on the C57Bl/6J background, that completely lack D4Rs (knockout or KO). In addition, the locomotor activity in these mice during the conditioning phase of CPP was tested in the CPP chambers. D4 receptor KO and WT mice showed CPP and increased locomotor activity in response to each of the three psychostimulants tested. D4R differentially modulates the CPP responses to MP, AMPH and cocaine. While the D4R genotype affected CPP responses to MP (high dose only) and AMPH (low dose only) it had no effects on cocaine. Inasmuch as CPP is considered an indicator of sensitivity to reinforcing responses to drugs these data suggest a significant but limited role of D4Rs in modulating conditioning responses to MP and AMPH. In the locomotor test, D4 receptor KO mice displayed attenuated increases in AMPH-induced locomotor activity whereas responses to cocaine and MP did not differ. These results suggest distinct mechanisms for D4 receptor modulation of the reinforcing (perhaps via attenuating dopaminergic signalling) and locomotor properties of these stimulant drugs

  17. A risk-based evaluation of LMFBR containment response under core disruptive accident conditions

    International Nuclear Information System (INIS)

    Hartung, J.; Berk, S.

    1978-01-01

    Probabilistic risk methodology is utilized to evaluate the failure modes and effects of LMFBR containment systems under Core Disruptive Accident (CDA) conditions. First, the potential causes of LMFBR containment failure under CDA conditions are discussed and categorized. Then, a simple scoping-type risk assessment of a reference design is presented to help place these potential causes of failure in perspective. The highest risk containment failure modes are identified for the reference design, and several design and research and development options which appear capable of reducing these risks are discussed. The degree to which large LMFBR containment systems must mitigate the consequences of CDA's to achieve a level of risk (for LMFBR's) comparable to the already very low risk of contemporary LWR's is explored. Based on the results of this evaluation, several suggestions are offered concerning CDA-related design goals and research and development priorities for large LMFBR's. (author)

  18. Learning deficits expressed as delayed extinction of a conditioned running response following perinatal exposure to vinclozolin.

    Science.gov (United States)

    André, Susan M; Markowski, Vincent P

    2006-01-01

    Vinclozolin (Vz) is one member of a group of fungicides whose metabolites are androgen receptor antagonists. These fungicides have been shown to block androgen-driven development and compromise reproductive function. The current study sought to determine if Vz also affects learning following exposure to low doses during the perinatal period. To test this, an androgen-dependent behavior was examined, the extinction of a previously reinforced running response. Pregnant Long-Evans rats were administered a daily oral dose of 0, 1.5, 3, 6 or 12 mg/kg Vz from the 14th day of gestation through postnatal day 3. After reaching adulthood, male and female offspring were trained to run through a short alleyway for food reinforcement. Acquisition of the response was not affected by Vz exposure. However, males required more trials than females for response extinction once food was no longer available in the apparatus. Males exposed to 6 or 12 mg/kg Vz failed to show any extinction by the end of the procedure, while the lowest dose of Vz appeared to facilitate extinction in both male and female offspring. These results demonstrate that endocrine disrupting antiandrogens can alter nervous system development in addition to the reproductive system.

  19. CORPORATE SOCIAL RESPONSIBILITY AS CONDITION OF INCLUDING UKRAINE IN EUROPE AND WORLD ECONOMIC SPACE

    Directory of Open Access Journals (Sweden)

    T. Lytvynenko

    2013-09-01

    Full Text Available The thesis that companies’ activities for introduction of corporate social responsibility stimulates the speed of to the processes of the technical upgrade, modernization of company’s activity and increase of its profitability is proved within the article. Those Ukrainian companies, which have high index of activities transparency, are also the most profitable. However, we can’t observe any significant increment of number of companies joining the Global agreement. One of the explanations we could name is the unproved idea supported by some politicians and economists about a shadow (‘black’ market that allegedly allows creating workplaces and taking off social tension in society on the certain stage. Insignificant values of index of citizens’ trust to activity of industries holds on the development socially of responsible business. Trust considered as a part of the general social capital. The Government of Ukraine must support initiative of companies to introduce social responsibility of business, as many European governments do it. It is also important to inform society of advantages of CSR.

  20. High-latitude ionospheric response to a sudden impulse event during northward IMF conditions

    DEFF Research Database (Denmark)

    Moretto, T.; Ridley, A.J.; Engebretson, M.J.

    2000-01-01

    A high-density structure under northward interplanetary magnetic field B-z conditions is identified at the Wind and IMP 8 satellites, both in the solar wind on August 22, 1995. A compression of the magnetosphere is observed by the GOES 7 magnetometer within a few minutes of the pressure increase ...... the interpretation as events of traveling convection vortices, as has been suggested by past studies....

  1. Development of quick-response area-averaged void fraction meter. Application to BWR condition

    Energy Technology Data Exchange (ETDEWEB)

    Iguchi, Tadashi; Watanabe, Hironori; Kimura, Mamoru; Anoda, Yoshinari [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment

    2001-05-01

    Authors have been developed a practical conductance-type void fraction meter to measure instantaneously area-averaged void fraction in rod bundle. The principle of the meter is based on the fact that the electrical conductance changes with the change of void fraction in gas-liquid two-phase flow. According to air/water two-phase flow experiment, the void fraction was approximated by {alpha}=1-I/I{sub 0}, where {alpha} and I are void fraction and current (I{sub 0} is current at {alpha}=0). Authors investigated the performance of the void fraction meter under high temperature/high pressure conditions (BWR condition; 290degC, 7MPa). The results indicated that the void fraction was approximated by {alpha}=1-I/I{sub 0} even under high temperature/high pressure condition of stem/water flow. However, it is necessary to take account of temperature dependency of water specific conductance. Therefore, authors derived a correction equation for temperature dependency. Further, for applying the void fraction meter to a large-scale facility, it was found to be necessary to reduce the capacitance of the circuit. Then, authors developed the method to reduce the capacitance effect. Finally, authors succeeded to measure the void fraction in 2 x 2 bundle flow path at the range of 0% - 70% in the error of 10% under high temperature/high pressure and mass flux of less than 133 kg/m{sup 2}s. Developed void fraction meter is theoretically not affected by flow rate. Therefore, it can be applied to the condition of oscillating flow. (author)

  2. Lettuce and rhizosphere microbiome responses to growth promoting Pseudomonas species under field conditions.

    Science.gov (United States)

    Cipriano, Matheus A P; Lupatini, Manoeli; Lopes-Santos, Lucilene; da Silva, Márcio J; Roesch, Luiz F W; Destéfano, Suzete A L; Freitas, Sueli S; Kuramae, Eiko E

    2016-12-01

    Plant growth promoting rhizobacteria are well described and recommended for several crops worldwide. However, one of the most common problems in research into them is the difficulty in obtaining reproducible results. Furthermore, few studies have evaluated plant growth promotion and soil microbial community composition resulting from bacterial inoculation under field conditions. Here we evaluated the effect of 54 Pseudomonas strains on lettuce (Lactuca sativa) growth. The 12 most promising strains were phylogenetically and physiologically characterized for plant growth-promoting traits, including phosphate solubilization, hormone production and antagonism to pathogen compounds, and their effect on plant growth under farm field conditions. Additionally, the impact of beneficial strains on the rhizospheric bacterial community was evaluated for inoculated plants. The strains IAC-RBcr4 and IAC-RBru1, with different plant growth promoting traits, improved lettuce plant biomass yields up to 30%. These two strains also impacted rhizosphere bacterial groups including Isosphaera and Pirellula (phylum Planctomycetes) and Acidothermus, Pseudolabrys and Singusphaera (phylum Actinobacteria). This is the first study to demonstrate consistent results for the effects of Pseudomonas strains on lettuce growth promotion for seedlings and plants grown under tropical field conditions. © FEMS 2016. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  3. The response of substance use disorder treatment providers to changes in macroeconomic conditions.

    Science.gov (United States)

    Cantor, Jonathan; Stoller, Kenneth B; Saloner, Brendan

    2017-10-01

    To study how substance use disorder (SUD) treatment providers respond to changes in economic conditions. 2000-2012 National Survey of Substance Abuse Treatment Services (N-SSATS) which contains detailed information on specialty SUD facilities in the United States. We use fixed-effects regression to study how changes in economic conditions, proxied by state unemployment rates, impact treatment setting, accepted payment forms, charity care, offered services, special programs, and use of pharmacotherapies by specialty SUD treatment providers. Secondary data analysis in the N-SSATS. Our findings suggest a one percentage point increase in the state unemployment rate is associated with a 2.5% reduction in outpatient clients by non-profit providers and a 1.8% increase in the acceptance of private insurance as a form of payment overall. We find no evidence that inpatient treatment, the provision of charity care, offered services, or special programs are impacted by changes in the state unemployment rate. However, a one percentage point increase in the state unemployment rate leads to a 2.5% increase in the probability that a provider uses pharmacotherapies to treat addiction. Deteriorating economic conditions may increase financial pressures on treatment providers, prompting them to seek new sources of revenue or to change their care delivery models. Copyright © 2017 Elsevier Inc. All rights reserved.

  4. About decision of question of social conditionality to the law on criminal responsibility in labours of O. V. Naden

    Directory of Open Access Journals (Sweden)

    О. О. Пащенко

    2013-10-01

    Full Text Available The scientific looks of О. V. Naden in relation to the problem of social conditionality of criminal legislation are investigated. Factors that are offered to take into account a legislator during setting of criminal responsibility for certain kind’s publicly dangerous behavior are considered. The realizable a scientist attempt of decision of problem is analyzed at general level by means of determination of limits of sphere of the criminal and legal adjusting.

  5. Response Analysis on Electrical Pulses under Severe Nuclear Accident Temperature Conditions Using an Abnormal Signal Simulation Analysis Module

    Directory of Open Access Journals (Sweden)

    Kil-Mo Koo

    2012-01-01

    Full Text Available Unlike design basis accidents, some inherent uncertainties of the reliability of instrumentations are expected while subjected to harsh environments (e.g., high temperature and pressure, high humidity, and high radioactivity occurring in severe nuclear accident conditions. Even under such conditions, an electrical signal should be within its expected range so that some mitigating actions can be taken based on the signal in the control room. For example, an industrial process control standard requires that the normal signal level for pressure, flow, and resistance temperature detector sensors be in the range of 4~20 mA for most instruments. Whereas, in the case that an abnormal signal is expected from an instrument, such a signal should be refined through a signal validation process so that the refined signal could be available in the control room. For some abnormal signals expected under severe accident conditions, to date, diagnostics and response analysis have been evaluated with an equivalent circuit model of real instruments, which is regarded as the best method. The main objective of this paper is to introduce a program designed to implement a diagnostic and response analysis for equivalent circuit modeling. The program links signal analysis tool code to abnormal signal simulation engine code not only as a one body order system, but also as a part of functions of a PC-based ASSA (abnormal signal simulation analysis module developed to obtain a varying range of the R-C circuit elements in high temperature conditions. As a result, a special function for abnormal pulse signal patterns can be obtained through the program, which in turn makes it possible to analyze the abnormal output pulse signals through a response characteristic of a 4~20 mA circuit model and a range of the elements changing with temperature under an accident condition.

  6. Fuzzy Stochastic Unit Commitment Model with Wind Power and Demand Response under Conditional Value-At-Risk Assessment

    Directory of Open Access Journals (Sweden)

    Jiafu Yin

    2018-02-01

    Full Text Available With the increasing penetration of wind power and demand response integrated into the grid, the combined uncertainties from wind power and demand response have been a challenging concern for system operators. It is necessary to develop an approach to accommodate the combined uncertainties in the source side and load side. In this paper, the fuzzy stochastic conditional value-at-risk criterions are proposed as the risk measure of the combination of both wind power uncertainty and demand response uncertainty. To improve the computational tractability without sacrificing the accuracy, the fuzzy stochastic chance-constrained goal programming is proposed to transfer the fuzzy stochastic conditional value-at-risk to a deterministic equivalent. The operational risk of forecast error under fuzzy stochastic conditional value-at-risk assessment is represented by the shortage of reserve resource, which can be further divided into the load-shedding risk and the wind curtailment risk. To identify different priority levels for the different objective functions, the three-stage day-ahead unit commitment model is proposed through preemptive goal programming, in which the reliability requirement has the priority over the economic operation. Finally, a case simulation is performed on the IEEE 39-bus system to verify the effectiveness and efficiency of the proposed model.

  7. The social responsibility as the basis for effective management and the condition for increasing the modern organization competitiveness

    Directory of Open Access Journals (Sweden)

    M. A. Gurina

    2017-01-01

    Full Text Available The article deals with the organization management based on the strategy of social responsibility implementation that supplies the conditions for a company's competitiveness development. The theoretical statements by the leading foreign researchers about the key role of social factors in an organization success and the main conditions of competitiveness such as human resources, staff competences, customers' pleasure, an organization's reputation, organizational and managing capacity, etc. The author discusses the idea of the new aim of the management paradigm is "social business" development in the economy. Despite the fact that entrepreneurship is still based on getting the economical benefit, the competitive area, the methods and the relationship between the profit and the competitiveness have changed in the post-industrial era. The change of the consuming society structure and the complication of the competitive area make us look for other sources of competitiveness, such as investments into the human resources. Such an approach to competitiveness is more and more spread among the foreign and national companies and allows to include social aspects management into the development strategy of a company. It is stated that a socially responsible company includes social goals in the production process, thus ensuring a competitive advantage in business. An important conclusion of the research is that socially responsible organizations create better conditions for the territories’ development where they provide the society with a generally higher welfare level.

  8. Optimization extraction conditions for improving phenolic content and antioxidant activity in Berberis asiatica fruits using response surface methodology (RSM).

    Science.gov (United States)

    Belwal, Tarun; Dhyani, Praveen; Bhatt, Indra D; Rawal, Ranbeer Singh; Pande, Veena

    2016-09-15

    This study for the first time designed to optimize the extraction of phenolic compounds and antioxidant potential of Berberis asiatica fruits using response surface methodology (RSM). Solvent selection was done based on the preliminary experiments and a five-factors-three-level, Central Composite Design (CCD). Extraction temperature (X1), sample to solvent ratio (X3) and solvent concentration (X5) significantly affect response variables. The quadratic model well fitted for all the responses. Under optimal extraction conditions, the dried fruit sample mixed with 80% methanol having 3.0 pH in a ratio of 1:50 and the mixture was heated at 80 °C for 30 min; the measured parameters was found in accordance with the predicted values. High Performance Liquid Chromatography (HPLC) analysis at optimized condition reveals 6 phenolic compounds. The results suggest that optimization of the extraction conditions is critical for accurate quantification of phenolics and antioxidants in Berberis asiatica fruits, which may further be utilized for industrial extraction procedure. Copyright © 2016 Elsevier Ltd. All rights reserved.

  9. Graph-based semi-supervised learning with genomic data integration using condition-responsive genes applied to phenotype classification.

    Science.gov (United States)

    Doostparast Torshizi, Abolfazl; Petzold, Linda R

    2018-01-01

    Data integration methods that combine data from different molecular levels such as genome, epigenome, transcriptome, etc., have received a great deal of interest in the past few years. It has been demonstrated that the synergistic effects of different biological data types can boost learning capabilities and lead to a better understanding of the underlying interactions among molecular levels. In this paper we present a graph-based semi-supervised classification algorithm that incorporates latent biological knowledge in the form of biological pathways with gene expression and DNA methylation data. The process of graph construction from biological pathways is based on detecting condition-responsive genes, where 3 sets of genes are finally extracted: all condition responsive genes, high-frequency condition-responsive genes, and P-value-filtered genes. The proposed approach is applied to ovarian cancer data downloaded from the Human Genome Atlas. Extensive numerical experiments demonstrate superior performance of the proposed approach compared to other state-of-the-art algorithms, including the latest graph-based classification techniques. Simulation results demonstrate that integrating various data types enhances classification performance and leads to a better understanding of interrelations between diverse omics data types. The proposed approach outperforms many of the state-of-the-art data integration algorithms. © The Author 2017. Published by Oxford University Press on behalf of the American Medical Informatics Association. All rights reserved. For Permissions, please email: journals.permissions@oup.com

  10. Optimization of fermentation conditions for 1,3-propanediol production by marine Klebsiella pneumonia HSL4 using response surface methodology

    Science.gov (United States)

    Li, Lili; Zhou, Sheng; Ji, Huasong; Gao, Ren; Qin, Qiwei

    2014-09-01

    The industrially important organic compound 1,3-propanediol (1,3-PDO) is mainly used as a building block for the production of various polymers. In the present study, response surface methodology protocol was followed to determine and optimize fermentation conditions for the maximum production of 1,3-PDO using marine-derived Klebsiella pneumoniae HSL4. Four nutritional supplements together with three independent culture conditions were optimized as follows: 29.3 g/L glycerol, 8.0 g/L K2 HPO4, 7.6 g/L (NH4)2 SO4, 3.0 g/L KH2 PO4, pH 7.1, cultivation at 35°C for 12 h. Under the optimal conditions, a maximum 1,3-PDO concentration of 14.5 g/L, a productivity of 1.21 g/(L·h) and a conversion of glycerol of 0.49 g/g were obtained. In comparison with the control conditions, fermentation under the optimized conditions achieved an increase of 38.8% in 1,3-PDO concentration, 39.0% in productivity and 25.7% in glycerol conversion in flask. This enhancement trend was further confirmed when the fermentation was conducted in a 5-L fermentor. The optimized fermentation conditions could be an important basis for developing lowcost, large-scale methods for industrial production of 1,3-PDO in the future.

  11. An Outbreak of Aspergillus Species in Response to Environmental Conditions in Serbia

    Directory of Open Access Journals (Sweden)

    Jelena Lević

    2013-01-01

    Full Text Available The frequency and incidence of A. flavus and A. niger on barley, maize, soybean, sunflowerand wheat grain, the abundance of European corn borer (Ostrinia nubilalis mothsand their interaction depending on weather conditions in the 2008-2012 period were studied.Under the agroecological conditions of Serbia, the species A. niger is more frequentthan A. flavus, and concerning the crop species, its frequency is highest in kernels of sunflower,than soybean, maize, barley and wheat. A. flavus was extremely dominant on allplant species in 2012 regarding its frequency: 100% on soybean, 95.3% on maize, 65.2% onbarley, 57.1% on sunflower and 45.8% on wheat. Furthermore, the incidence of A. flavus washigher in 2012 than in previous years. The uncommonly high frequency and incidence of A.flavus infestation of maize grain in 2012 were caused by extremely stressful agrometeorologicalconditions, high temperatures and drought over the period from flowering to waxymaturity of maize. The precipitation factor (Pf = precipitation sum / average monthly temperatureshowed that 2012 was extremely arid in June (Pf = 0.57, July (Pf = 1.45, August (Pf= 0.15 and September (Pf = 1.42. European corn borer (ECB was a second factor causingintensive occurrence of A. flavus on maize grain in 2012. The maximum flight of ECB mothswas recorded as early as in July (5,149 and, as a result of this, high damage and numerousinjuries were detected at harvest. Those injuries were covered by visible olive-green powderycolonies typical of A. flavus. In the chronology of A. flavus occurrence, these are thefirst data on its very high frequency and incidence under the agroecological conditions ofSerbia. As intensive infections with A. flavus were rare in the past 50 years, the level of aflatoxinsin maize grain was low.

  12. Early growth response of six wheat varieties under artificial osmotic stress condition

    International Nuclear Information System (INIS)

    Khakwani, A.A.; Dennett, M.D.; Munir, M

    2011-01-01

    An experiment was carried out under laboratory conditions where seeds of six wheat varieties (Damani, Hashim-8, Gomal-8, DN-73, Zam-04 and Dera-98) were raised in Petri dishes and were either treated with distilled water (control) or 15% polyethylene glycol (PEG) 6000 solution. Seeds were treated with 15% PEG solution to establish an artificial osmotic stress condition (water stress) and observe its effect on germination percentage, coleoptile length, shoot and root length, fresh weight of shoot and root. A significant difference (P<0.05) was recorded between varietal and treatment means regarding all traits. Variety Hashim-8 gave maximum germination percentage (93.33%) whereas maximum coleoptile (1.78 cm) and shoot length (5.77 cm) was observed in variety DN-73 which was statistically at par with variety Hashim-8. Similarly, root length (3.63 g), fresh shoot (0.15 g) and root weight (0.12 g) was maximum in variety Dera-98 which was statistically at par with variety Hashim-8. A second experiment was carried out under glass house environment where plants were treated with non-stress (100% field capacity) and water stress (35% field capacity) treatments. Although total grain yield was significantly (P<0.05) reduced in all six wheat varieties when grown in water stress condition however Hashim-8 showed the lowest reduction (13%) while Zam-04 showed the highest (32%). The outcome of both experiments indicated that these varieties have great potential to incorporate with the existing commercial wheat varieties in order to obtain high yield in water stress regions. (author)

  13. Physical activity, pain responses to heat stimuli, and conditioned pain modulation in postmenopausal women.

    Science.gov (United States)

    Adrian, Amanda L; O'Connor, Patrick J; Ward-Ritacco, Christie L; Evans, Ellen M

    2015-08-01

    Postmenopausal women (PMW) are at high risk for disabling pain and physical inactivity. This study sought to enhance the understanding of relationships between physical activity (PA) and pain among PMW using heat pain sensitivity test and conditioned pain modulation test. We hypothesized that, compared with active women, (i) inactive women would report higher pain intensity and pain unpleasantness ratings; (ii) inactive women in disabling pain would report higher pain intensity and pain unpleasantness at high, but not low, stimulus intensities; and (iii) inactive women would have less modulation. Sixty-eight PMW rated the pain intensity and pain unpleasantness of hot stimuli presented to the thenar eminence of the hand. A subset of 31 women rated the pain intensity of a test stimulus (noxious heat) and a conditioning stimulus (cold water) as part of the conditioned pain modulation task. PA was assessed objectively with accelerometry. Mixed-model analysis of variance (2 × 4 × 2; PA × Temperature × Pain Status) showed that inactive women in disabling pain rated pain unpleasantness higher than active women in disabling pain (F3,192 = 3.526, ∂η = 0.052, P = 0.016). Significantly lower pain unpleasantness ratings were found at the highest stimulus intensity (49°C) only for active women in disabling pain compared with inactive women in disabling pain (t11 = 2.523, P = 0.028). The other hypotheses were not supported. PA is associated with a reduced sensitivity to the unpleasantness of painful high-intensity heat stimuli among women in disabling pain.

  14. A radioactive waste transportation package monitoring system for normal transport and accident emergency response conditions

    International Nuclear Information System (INIS)

    Brown, G.S.; Cashwell, J.W.; Apple, M.L.

    1991-01-01

    Shipments of radioactive material (RAM) constitute but a small fraction of the total hazardous materials shipped in the United States each year. Public perception, however, of the potential consequences of a release from a transportation package containing RAM has resulted in significant regulation of transport operations, both to ensure the integrity of a package in accident conditions and to place operational constraints on the shipper. Much of this attention has focused on shipments of spent nuclear fuel and high level wastes which, although comprising a very small number of total shipments, constitute a majority of the total curies transported on an annual basis. This report discusses the shipment of these highly radioactive materials

  15. Response of exciton polariton spectra and electric fields to different additional boundary conditions

    International Nuclear Information System (INIS)

    Nkoma, J.S.

    1982-08-01

    The effects of three additional boundary conditions (ABC's) on the reflection and transmission spectra for exciton polaritons propagating in a spatially dispersive media are studied for both p and s configurations. An investigation of the ratios of the electric field amplitudes associated with the normal modes in these media is carried out. There is qualitative agreement among the predictions of the different ABC's, but there are significant quantitative differences, especially in the longitudinal polariton spike excited only in the p-geometry. Contact with formulations not using the ABC approach is made. The results are illustrated by parameters modelling the 1s exciton of PbI 2 . (author)

  16. Influence of the added mass effect and boundary conditions on the dynamic response of submerged and confined structures

    International Nuclear Information System (INIS)

    Valentín, D; Presas, A; Egusquiza, E; Valero, C

    2014-01-01

    The dynamic response of submerged and confined disk-like structures is of interest in the flied of hydraulic machinery, especially in hydraulic turbine runners. This response is difficult to be estimated with accuracy due to the strong influence of the boundary conditions. Small radial gaps as well as short axial distances to rigid surfaces greatly modify the dynamic response because the fact of the added mass and damping effects. Moreover, the effect of the shaft coupling is also important for certain mode-shapes of the structure. In the present study, the influence of the added mass effect and boundary conditions on the dynamic behavior of a submerged disk attached to a shaft is evaluated through experimental tests and structural- acoustic coupling numerical simulations. For the experimentation, a test rig has been developed. It consists of a confined disk attached to a shaft inside a cylindrical container full of water. The disk can be fixed at different axial positions along the shaft. Piezoelectric patches are used to excite the disk and the response is measured with submersible accelerometers. For each configuration tested, the natural frequencies of the disk and the shaft are studied. Numerical results have been compared with experimental results

  17. X-ray conditions and response characteristics of automatic dose control in cinematography

    International Nuclear Information System (INIS)

    Arai, Hiroaki

    1997-01-01

    X-ray characteristics including subject thickness (copper plate), tube voltage, tube current and irradiation time were measured at stability, with an automatic dose control x-ray generator for cineangiography. Regardless of subject thickness, it is possible that the energy input to the x-ray tube in one frame may be decreased. The automatic control response was measured after rapid fluctuation in subject thickness. Two inverter-type x-ray generators with different automatic control units were studied. The older control unit changes exposure dose by tube voltage and tube current, while the newer one changes exposure dose by tube voltage, tube current and irradiation time. The maximum rate of change in tube voltage is greater with the newer control unit. In addition, the actual tube current response of the newer control unit in increasing nominal value is faster than the older one. In the new control unit, for each pulse, irradiation is cut off by means of a signal that the exposure has reached the proper value. Thus given the same differential in subject thickness, the newer control unit resumed stability faster than the older one. (author)

  18. Keto analogue and amino acid supplementation affects the ammonaemia response during exercise under ketogenic conditions.

    Science.gov (United States)

    Prado, Eduardo Seixas; de Rezende Neto, José Melquiades; de Almeida, Rosemeire Dantas; Dória de Melo, Marcelia Garcez; Cameron, Luiz-Claudio

    2011-06-28

    Hyperammonaemia is related to both central and peripheral fatigue during exercise. Hyperammonaemia in response to exercise can be reduced through supplementation with either amino acids or combined keto analogues and amino acids (KAAA). In the present study, we determined the effect of short-term KAAA supplementation on ammonia production in subjects eating a low-carbohydrate diet who exercise. A total of thirteen male cyclists eating a ketogenic diet for 3 d were divided into two groups receiving either KAAA (KEx) or lactose (control group; LEx) supplements. Athletes cycled indoors for 2 h, and blood samples were obtained at rest, during exercise and over the course of 1 h during the recovery period. Exercise-induced ammonaemia increased to a maximum of 35 % in the control group, but no significant increase was observed in the supplemented group. Both groups had a significant increase (approximately 35 %) in uraemia in response to exercise. The resting urate levels of the two groups were equivalent and remained statistically unchanged in the KEx group after 90 min of exercise; an earlier increase was observed in the LEx group. Glucose levels did not change, either during the trial time or between the groups. An increase in lactate levels was observed during the first 30 min of exercise in both groups, but there was no difference between the groups. The present results suggest that the acute use of KAAA diminishes exercise-induced hyperammonaemia.

  19. X-ray conditions and response characteristics of automatic dose control in cinematography

    Energy Technology Data Exchange (ETDEWEB)

    Arai, Hiroaki [Cardiovascular Institute Hospital, Tokyo (Japan)

    1997-11-01

    X-ray characteristics including subject thickness (copper plate), tube voltage, tube current and irradiation time were measured at stability, with an automatic dose control x-ray generator for cineangiography. Regardless of subject thickness, it is possible that the energy input to the x-ray tube in one frame may be decreased. The automatic control response was measured after rapid fluctuation in subject thickness. Two inverter-type x-ray generators with different automatic control units were studied. The older control unit changes exposure dose by tube voltage and tube current, while the newer one changes exposure dose by tube voltage, tube current and irradiation time. The maximum rate of change in tube voltage is greater with the newer control unit. In addition, the actual tube current response of the newer control unit in increasing nominal value is faster than the older one. In the new control unit, for each pulse, irradiation is cut off by means of a signal that the exposure has reached the proper value. Thus given the same differential in subject thickness, the newer control unit resumed stability faster than the older one. (author)

  20. "Isocrater" impacts: Conditions and mantle dynamical responses for different impactor types

    Science.gov (United States)

    Ruedas, Thomas; Breuer, Doris

    2018-05-01

    Impactors of different types and sizes can produce a final crater of the same diameter on a planet under certain conditions. We derive the condition for such "isocrater impacts" from scaling laws, as well as relations that describe how the different impactors affect the interior of the target planet; these relations are also valid for impacts that are too small to affect the mantle. The analysis reveals that in a given isocrater impact, asteroidal impactors produce anomalies in the interior of smaller spatial extent than cometary or similar impactors. The differences in the interior could be useful for characterizing the projectile that formed a given crater on the basis of geophysical observations and potentially offer a possibility to help constrain the demographics of the ancient impactor population. A series of numerical models of basin-forming impacts on Mercury, Venus, the Moon, and Mars illustrates the dynamical effects of the different impactor types on different planets. It shows that the signature of large impacts may be preserved to the present in Mars, the Moon, and Mercury, where convection is less vigorous and much of the anomaly merges with the growing lid. On the other hand, their signature will long have been destroyed in Venus, whose vigorous convection and recurring lithospheric instabilities obliterate larger coherent anomalies.

  1. Using Magnetically Responsive Tea Waste to Remove Lead in Waters under Environmentally Relevant Conditions

    KAUST Repository

    Yeo, Siang Yee; Choi, Siwon; Dien, Vivian; Sow-Peh, Yoke Keow; Qi, Genggeng; Hatton, T. Alan; Doyle, Patrick S.; Thio, Beng Joo Reginald

    2013-01-01

    We report the use of a simple yet highly effective magnetite-waste tea composite to remove lead(II) (Pb2+) ions from water. Magnetite-waste tea composites were dispersed in four different types of water–deionized (DI), artificial rainwater, artificial groundwater and artificial freshwater–that mimic actual environmental conditions. The water samples had varying initial concentrations (0.16–5.55 ppm) of Pb2+ ions and were mixed with the magnetite-waste tea composite for at least 24 hours to allow adsorption of the Pb2+ ions to reach equilibrium. The magnetite-waste tea composites were stable in all the water samples for at least 3 months and could be easily removed from the aqueous media via the use of permanent magnets. We detected no significant leaching of iron (Fe) ions into the water from the magnetite-waste tea composites. The percentage of Pb adsorbed onto the magnetite-waste tea composite ranged from ~70% to 100%; the composites were as effective as activated carbon (AC) in removing the Pb2+ ions from water, depending on the initial Pb concentration. Our prepared magnetite-waste tea composites show promise as a green, inexpensive and highly effective sorbent for removal of Pb in water under environmentally realistic conditions.

  2. Using Magnetically Responsive Tea Waste to Remove Lead in Waters under Environmentally Relevant Conditions

    KAUST Repository

    Yeo, Siang Yee

    2013-06-20

    We report the use of a simple yet highly effective magnetite-waste tea composite to remove lead(II) (Pb2+) ions from water. Magnetite-waste tea composites were dispersed in four different types of water–deionized (DI), artificial rainwater, artificial groundwater and artificial freshwater–that mimic actual environmental conditions. The water samples had varying initial concentrations (0.16–5.55 ppm) of Pb2+ ions and were mixed with the magnetite-waste tea composite for at least 24 hours to allow adsorption of the Pb2+ ions to reach equilibrium. The magnetite-waste tea composites were stable in all the water samples for at least 3 months and could be easily removed from the aqueous media via the use of permanent magnets. We detected no significant leaching of iron (Fe) ions into the water from the magnetite-waste tea composites. The percentage of Pb adsorbed onto the magnetite-waste tea composite ranged from ~70% to 100%; the composites were as effective as activated carbon (AC) in removing the Pb2+ ions from water, depending on the initial Pb concentration. Our prepared magnetite-waste tea composites show promise as a green, inexpensive and highly effective sorbent for removal of Pb in water under environmentally realistic conditions.

  3. Physiological response of invasive mussel Limnoperna fortunei (Dunker, 1857 (Bivalvia: Mytilidae submitted to transport and experimental conditions

    Directory of Open Access Journals (Sweden)

    N. I. S. Cordeiro

    Full Text Available Abstract Successful animal rearing under laboratory conditions for commercial processes or laboratory experiments is a complex chain that includes several stressors (e.g., sampling and transport and incurs, as a consequence, the reduction of natural animal conditions, economic losses and inconsistent and unreliable biological results. Since the invasion of the bivalve Limnoperna fortunei (Dunker, 1857 in South America, several studies have been performed to help control and manage this fouling pest in industrial plants that use raw water. Relatively little attention has been given to the laboratory rearing procedure of L. fortunei, its condition when exposed to a stressor or its acclimation into laboratory conditions. Considering this issue, the aims of this study are to (i investigate L. fortunei physiological responses when submitted to the depuration process and subsequent air transport (without water/dry condition at two temperatures, based on glycogen concentrations, and (ii monitor the glycogen concentrations in different groups when maintained for 28 days under laboratory conditions. Based on the obtained results, depuration did not affect either of the groups when they were submitted to approximately eight hours of transport. The variation in glycogen concentration among the specimens that were obtained from the field under depurated and non-depurated conditions was significant only in the first week of laboratory growth for the non-depurated group and in the second week for the depurated group. In addition, the tested temperature did not affect either of the groups that were submitted to transport. The glycogen concentrations were similar to those of the specimens that were obtained from the field in third week, which suggests that the specimens acclimated to laboratory conditions during this period of time. Thus, the results indicate that the air transport and acclimation time can be successfully incorporated into experimental studies

  4. A NMDA receptor antagonist, MK-801 impairs consolidating extinction of auditory conditioned fear responses in a Pavlovian model.

    Directory of Open Access Journals (Sweden)

    Jun-Li Liu

    Full Text Available BACKGROUND: In auditory fear conditioning, repeated presentation of the tone in the absence of shock leads to extinction of the acquired fear responses. The glutamate N-methyl-D-aspartate receptor (NMDAR is thought to be involved in the extinction of the conditioned fear responses, but its detailed role in initiating and consolidating or maintaining the fear extinction memory is unclear. Here we investigated this issue by using a NMDAR antagonist, MK-801. METHODS/MAIN FINDINGS: The effects of immediate (beginning at 10 min after the conditioning and delayed (beginning at 24 h after conditioning extinctions were first compared with the finding that delayed extinction caused a better and long-lasting (still significant on the 20(th day after extinction depression on the conditioned fear responses. In a second experiment, MK-801 was intraperitoneally (i.p. injected at 40 min before, 4 h or 12 h after the delayed extinction, corresponding to critical time points for initiating, consolidating or maintaining the fear extinction memory. i.p. injection of MK-801 at either 40 min before or 4 h after delayed extinction resulted in an impairment of initiating and consolidating fear extinction memory, which caused a long lasting increased freezing score that was still significant on the 7th day after extinction, compared with extinction group. However, MK-801 administered at 12 h after the delayed extinction, when robust consolidation has been occurred and stabilized, did not affect the established extinction memory. Furthermore, the changed freezing behaviors was not due to an alteration in general anxiety levels, since MK-801 treatment had no effect on the percentage of open-arm time or open-arm entries in an Elevated Plus Maze (EPM task. CONCLUSIONS/SIGNIFICANCE: Our data suggested that the activation of NMDARs plays important role in initiation and consolidation but not maintenance of fear extinction memory. Together with the fact that NMDA receptor is

  5. ARKTOS amphibious oil spill response craft for mixed ice/water conditions

    Energy Technology Data Exchange (ETDEWEB)

    Seligman, Bruce H.J.W. [ARKTOS International S.A., Tavannes (Switzerland)], email: bruce.seligman@arktoscraft.com; Hall, T.A. [Hall Marine Design Ltd., Vancouver B.C. (Canada)], email: thallhmd@telus.net

    2010-07-01

    The oil spill which occurred recently in the Gulf of Mexico highlighted the lack of efficient oil spill clean-up equipment for an offshore environment. With the increase in industrial operations in the Arctic Seas it is of high importance to develop an efficient oil spill response as the absence of reliable oil spill contingency plans will not be tolerated in such environmentally sensitive areas. The aim of this paper is to present the use of the ARKTOS amphibious craft for cleaning up an oil spill in the Arctic. This craft is usually used for logistical services and evacuation purposes; its use for clean-up purposes has been under study since 2000. This study showed that the ARKTOS craft could be an efficient means for oil spill clean-up in the Arctic because of its proven ice capable amphibious platforms and its hydraulic power; however oil collection trials should be performed to validate it.

  6. ARKTOS amphibious oil spill response craft for mixed ice/water conditions

    International Nuclear Information System (INIS)

    Seligman, Bruce H.J.W.; Hall, T.A.

    2010-01-01

    The oil spill which occurred recently in the Gulf of Mexico highlighted the lack of efficient oil spill clean-up equipment for an offshore environment. With the increase in industrial operations in the Arctic Seas it is of high importance to develop an efficient oil spill response as the absence of reliable oil spill contingency plans will not be tolerated in such environmentally sensitive areas. The aim of this paper is to present the use of the ARKTOS amphibious craft for cleaning up an oil spill in the Arctic. This craft is usually used for logistical services and evacuation purposes; its use for clean-up purposes has been under study since 2000. This study showed that the ARKTOS craft could be an efficient means for oil spill clean-up in the Arctic because of its proven ice capable amphibious platforms and its hydraulic power; however oil collection trials should be performed to validate it.

  7. Isoprenoid emission response to changing light conditions of English oak, European beech and Norway spruce

    DEFF Research Database (Denmark)

    Van Meeningen, Ylva; Schurgers, Guy; Rinnan, Riikka

    2017-01-01

    and stomatal conductance on three common European tree species, namely English oak (Quercus robur), European beech (Fagus sylvatica) and two provenances of Norway spruce (Picea abies) in Taastrup, Denmark. Leaf scale measurements were performed on the lowest positioned branches of the tree in July 2015. Light......, whereas other compounds, like camphene, had no significant emission response to light for most of the measured trees. English oak and European beech showed high light-dependent emission fractions from isoprene and sabinene, but other emitted compounds were light independent. For the two provenances...... be valid for a wider range of tree species. This information could be of importance when improving emission models and to further emphasize the discussion regarding light or temperature dependencies for individual compounds across species. Light is an important environmental factor controlling biogenic...

  8. No pain, no gain: the affective valence of congruency conditions changes following a successful response.

    Science.gov (United States)

    Schouppe, Nathalie; Braem, Senne; De Houwer, Jan; Silvetti, Massimo; Verguts, Tom; Ridderinkhof, K Richard; Notebaert, Wim

    2015-03-01

    The cognitive control theory of Botvinick, Cognitive, Affective, & Behavioral Neuroscience, 7, 356-366 (2007) integrates cognitive and affective control processes by emphasizing the aversive nature of cognitive conflict. Using an affective priming paradigm, we replicate earlier results showing that incongruent trials, relative to congruent trials, are indeed perceived as more aversive (Dreisbach & Fischer, Brain and Cognition, 78(2), 94-98 (2012)). Importantly, however, in two experiments we demonstrate that this effect is reversed following successful responses; correctly responding to incongruent trials engendered relatively more positive affect than correctly responding to congruent trials. The results are discussed in light of a recent computational model by Silvetti, Seurinck, and Verguts, Frontiers in Human Neuroscience, 5:75 (2011) where it is assumed that outcome expectancies are more negative for incongruent trials than congruent trials. Consequently, the intrinsic reward (prediction error) following successful completion is larger for incongruent than congruent trials. These findings divulge a novel perspective on 'cognitive' adaptations to conflict.

  9. Seasonally asymmetric transition of the Asian monsoon in response to ice age boundary conditions

    Energy Technology Data Exchange (ETDEWEB)

    Ueda, Hiroaki; Kuroki, Harumitsu; Kamae, Youichi [University of Tsukuba, Graduate School of Life and Environmental Sciences, Tsukuba, Ibaraki (Japan); Ohba, Masamichi [Central Research Institute of Electric Power Industry, Environmental Science Research Laboratory, Abiko (Japan)

    2011-12-15

    Modulation of a monsoon under glacial forcing is examined using an atmosphere-ocean coupled general circulation model (AOGCM) following the specifications established by Paleoclimate Modelling Intercomparison Project phase 2 (PMIP2) to understand the air-sea-land interaction under different climate forcing. Several sensitivity experiments are performed in response to individual changes in the continental ice sheet, orbital parameters, and sea surface temperature (SST) in the Last Glacial Maximum (LGM: 21 ka) to evaluate the driving mechanisms for the anomalous seasonal evolution of the monsoon. Comparison of the model results in the LGM with the pre-industrial (PI) simulation shows that the Arabian Sea and Bay of Bengal are characterized by enhancement of pre-monsoon convection despite a drop in the SST encompassing the globe, while the rainfall is considerably suppressed in the subsequent monsoon period. In the LGM winter relative to the PI, anomalies in the meridional temperature gradient (MTG) between the Asian continents minus the tropical oceans become positive and are consistent with the intensified pre-monsoon circulation. The enhanced MTG anomalies can be explained by a decrease in the condensation heating relevant to the suppressed tropical convection as well as positive insolation anomalies in the higher latitude, showing an opposing view to a warmer future climate. It is also evident that a latitudinal gradient in the SST across the equator plays an important role in the enhancement of pre-monsoon rainfall. As for the summer, the sensitivity experiments imply that two ice sheets over the northern hemisphere cools the air temperature over the Asian continent, which is consistent with the reduction of MTG involved in the attenuated monsoon. The surplus pre-monsoon convection causes a decrease in the SST through increased heat loss from the ocean surface; in other words, negative ocean feedback is also responsible for the subsequent weakening of summer

  10. Acupuncture Induces a Pro-Inflammatory Immune Response Intensified by a Conditioning-Expectation Effect

    DEFF Research Database (Denmark)

    Karst, M; Schneidewind, D; Schneinichen, D

    2010-01-01

    BACKGROUND: In a previous study it has been shown that acupuncture activates the respiratory burst (RB) of neutrophils as measured by the differences to baseline of the mean channel number of fluorescence intensity (mfi) in volunteers. Since this result could have been affected by a placebo effect......, a study has been designed that controls for the different facets of placebo mechanisms such as expectancy, suggestibility, and conditioning. PARTICIPANTS AND METHODS: 60 healthy volunteers were randomized either to acupuncture of the acupoint Large Intestine 11 (LI 11) (groups 1 and 2) or relaxation...... (group 3) twice a week for 4 weeks. Only acupuncture group 1 and the relaxation group were provided with the additional suggestion that the treatment may strengthen the immune system. RESULTS: The repeated measurement analysis for differences of follow-ups to baseline showed significantly different...

  11. Acupuncture induces a pro-inflammatory immune response intensified by a conditioning-expectation effect

    DEFF Research Database (Denmark)

    Karst, M.; Schneidewind, D.; Scheinchen, D.

    2010-01-01

    BACKGROUND: In a previous study it has been shown that acupuncture activates the respiratory burst (RB) of neutrophils as measured by the differences to baseline of the mean channel number of fluorescence intensity (mfi) in volunteers. Since this result could have been affected by a placebo effect......, a study has been designed that controls for the different facets of placebo mechanisms such as expectancy, suggestibility, and conditioning. PARTICIPANTS AND METHODS: 60 healthy volunteers were randomized either to acupuncture of the acupoint Large Intestine 11 (LI 11) (groups 1 and 2) or relaxation...... (group 3) twice a week for 4 weeks. Only acupuncture group 1 and the relaxation group were provided with the additional suggestion that the treatment may strengthen the immune system. RESULTS: The repeated measurement analysis for differences of follow-ups to baseline showed significantly different...

  12. Culture conditions affecting the survival response of Chinese hamster ovary cells treated by hyperthermia

    International Nuclear Information System (INIS)

    Highfield, D.P.; Holahan, E.V.; Dewey, W.C.

    1982-01-01

    Using lethally irradiated feeder cells to control cell population densities, researchers investigated the survival of Chinese hamster ovary cells heated between 42.2 and 45.5 degrees C. Test cells were plated into T25 flasks with or without feeder cells, incubated 2 hours at 37 degrees C, and then given various heat treatments. Under all heating conditions, survival increased in those flasks containing feeder cells. Increased survival (by as much as a factor of 100 for cells heated at 42.4 degrees C for 6-10 hr) was most apparent when cells were heated to thermotolerance. By adjustment of test and feeder cell numbers, survival increased as density increased; however, maximum survival followed a transition period that occurred between the plating of 1 X 10(4) and 6 X 10(4) cells. Experimental artifacts due to improper control of cell density was demonstrated

  13. Mediator phosphorylation prevents stress response transcription during non-stress conditions.

    Science.gov (United States)

    Miller, Christian; Matic, Ivan; Maier, Kerstin C; Schwalb, Björn; Roether, Susanne; Strässer, Katja; Tresch, Achim; Mann, Matthias; Cramer, Patrick

    2012-12-28

    The multiprotein complex Mediator is a coactivator of RNA polymerase (Pol) II transcription that is required for the regulated expression of protein-coding genes. Mediator serves as an end point of signaling pathways and regulates Pol II transcription, but the mechanisms it uses are not well understood. Here, we used mass spectrometry and dynamic transcriptome analysis to investigate a functional role of Mediator phosphorylation in gene expression. Affinity purification and mass spectrometry revealed that Mediator from the yeast Saccharomyces cerevisiae is phosphorylated at multiple sites of 17 of its 25 subunits. Mediator phosphorylation levels change upon an external stimulus set by exposure of cells to high salt concentrations. Phosphorylated sites in the Mediator tail subunit Med15 are required for suppression of stress-induced changes in gene expression under non-stress conditions. Thus dynamic and differential Mediator phosphorylation contributes to gene regulation in eukaryotic cells.

  14. Analysis of molecular responses in plants under the conditions of excess-aluminium stress

    Energy Technology Data Exchange (ETDEWEB)

    Masaoka, Yoshikuni; Arakawa, Yusuke; Asanuma, Shuichi [Kyushu National Agricultural Experiment Station, Kumamoto (Japan)] [and others

    1999-02-01

    Recent soil environments in Kyushu and Okinawa regions have a possibility to impair agricultural products because elution of aluminum (Al) from the soil has been progressing because of its elution by soil acidification. In this study, {sup 26}Al-tracing method using tandem accelerator mass spectroscopy was applied to investigate the effects of aluminum in the soil on a few plants. The results showed that Al accumulation in mitochondria was several times of higher in Dayton, a Al-resistant strain of barley than kearney, a sensitive one. It was thus suggested that mitochondria, which has been known to participates in respiration and cell death (apoptosis), has also an important role in the physiological functions of Al. The growth of barley on the soil of pH 5.0 was significantly inhibited with Al and such growth inhibition was also observed in barley grown in hydroponics, especially, the growth of kearney was markedly inhibited. When the effects of 1 mM Al were compared between Dayton and kearney strains, there were large differences in the growth of their leaves. Then, the correlative resistance to Al and barley leaf stripe mosaic virus (BSMV) was examined in these two barley strains. The virus concentration in kearney leaves 30 days after an inoculation of BSMV was similar to that in Dayton ones. Under stress conditions with a low level Al, both strains infected with BSMW developed necrotic damages, whereas under the stress condition at a high level Al (100 {mu}M), they developed severe necrosis even without inoculation with BSMW. As an increase of the amount of absorbed Al, the phosphate concentration in the cell was decreased and the decrease was marked in the resistant strain, Dayton. (M.N.)

  15. Responses to tonic heat pain in the ongoing EEG under conditions of controlled attention.

    Science.gov (United States)

    Giehl, Janet; Meyer-Brandis, Gesa; Kunz, Miriam; Lautenbacher, Stefan

    2014-03-01

    To confirm the existence of an ongoing electroencephalogram (EEG) pattern that is truly suggestive of pain, tonic heat pain was induced by small heat pulses at 1 °C above the pain threshold and compared to slightly less intense tonic non-painful heat pulses at 1 °C below the pain threshold. Twenty healthy subjects rated the sensation intensity during thermal stimulation. Possible confounding effects of attention were thoroughly controlled for by testing in four conditions: (1) focus of attention directed ipsilateral or (2) contralateral to the side of the stimulation, (3) control without a side preference, and (4) no control of attention at all. EEG was recorded via eight leads according to the 10/20 convention. Absolute power was computed for the frequency bands delta (0.5-4 Hz), theta (4-8 Hz), alpha1 (8-11 Hz), alpha2 (11-14 Hz), beta1 (14-25 Hz), and beta2 (25-35 Hz). Ratings were clearly distinct between the heat and pain conditions and suggestive for heat and pain sensations. Manipulation of attention proved to be successful by producing effects on the ratings and on the EEG activity (with lower ratings and lower EEG activity (theta, beta1, 2) over central areas for side-focused attention). During pain stimulation, lower central alpha1 and alpha2 activity and higher right-parietal and right-occipital delta power were observed compared to heat stimulation. This EEG pattern was not influenced by the manipulation of attention. Since the two types of stimuli (pain, heat) were subjectively felt differently although stimulation intensities were nearby, we conclude that this EEG pattern is clearly suggestive of pain.

  16. Transcriptional Responses of Chilean Quinoa (Chenopodium quinoa Willd.) Under Water Deficit Conditions Uncovers ABA-Independent Expression Patterns.

    Science.gov (United States)

    Morales, Andrea; Zurita-Silva, Andres; Maldonado, Jonathan; Silva, Herman

    2017-01-01

    HIGHLIGHTS R49 genotype displayed best performance on selected physiological parameters and highest tolerance to drought.R49 drought over-represented transcripts has exhibited 19% of genes (306 contigs) that presented no homology to published databases.Expression pattern for canonical responses to drought such as ABA biosynthesis and other genes induced in response to drought were assessed by qPCR. Global freshwater shortage is one of the biggest challenges of our time, often associated to misuse, increased consumption demands and the effects of climate change, paralleled with the desertification of vast areas. Chenopodium quinoa (Willd.) represents a very promising species, due to both nutritional content and cultivation under water constraint. We characterized drought tolerance of three Chilean genotypes and selected Genotype R49 (Salares ecotype) based upon Relative Water Content (RWC), Electrolyte Leakage (EL) and maximum efficiency of photosystem II (F v /F m ) after drought treatment, when compared to another two genotypes. Exploratory RNA-Seq of R49 was generated by Illumina paired-ends method comparing drought and control irrigation conditions. We obtained 104.8 million reads, with 54 million reads for control condition and 51 million reads for drought condition. Reads were assembled in 150,952 contigs, were 31,523 contigs have a reading frame of at least 300 nucleotides (100 aminoacids). BLAST2GO annotation showed a 15% of genes without homology to NCBI proteins, but increased to 19% (306 contigs) when focused into drought-induced genes. Expression pattern for canonical drought responses such as ABA biosynthesis and other genes induced were assessed by qPCR, suggesting novelty of R49 drought responses.

  17. Dopamine D1 receptor-dependent regulation of extracellular citrulline level in the rat nucleus accumbens during conditioned fear response.

    Science.gov (United States)

    Saulskaya, Natalia B; Fofonova, Nellia V; Sudorghina, Polina V; Saveliev, Sergey A

    2008-08-01

    Nucleus accumbens (N.Acc) contains a subclass of nitric oxide (NO)-generating interneurons that are presumably regulated by the dopamine input. Receptor mechanisms underlying dopamine-NO interaction in the N.Acc are poorly understood. In the current study, we used in vivo microdialysis combined with high-performance liquid chromatography to examine participation of dopamine D1 receptors in regulation of extracellular levels of citrulline (an NO co-product) in the medial N.Acc of Sprague-Dawley rats during both pharmacological challenge and a conditioned fear response. The intraaccumbal infusion of the D1 receptor agonist SKF-38393 (100-500 microM) increased dose-dependently the local dialysate citrulline levels. The SKF-38393-induced increase in extracellular citrulline was prevented by intraaccumbal infusions of 500 microM 7-nitroindazole, a neuronal NO synthase inhibitor. In behavioral microdialysis experiment, the accumbal levels of extracellular citrulline markedly increased in rats given a mild footshock paired with tone. The presentation of the tone previously paired with footshock (the conditioned fear response) produced a "conditioned" rise of extracellular citrulline levels in the N.Acc which was attenuated by intraaccumbal infusion of 100 microM SCH-23390, a dopamine D1 receptor antagonist, and prevented by intraaccumbal infusion of 500 microM 7-nitroindazole. The results suggest that in the N.Acc, the dopamine D1 receptors might regulate the neuronal NO synthase activity; this dopamine-dependent mechanism seems to participate in activation of the neuronal NO synthase and probably NO formation in this brain area during the conditioned fear response.

  18. The effects of air stoichiometry and air excess ratio on the transient response of a PEMFC under load change conditions

    International Nuclear Information System (INIS)

    Kim, Bosung; Cha, Dowon; Kim, Yongchan

    2015-01-01

    Highlights: • Effects of controlling parameters on the transient response of a PEMFC are studied. • The transient response is measured by varying air stoichiometry and air excess ratio. • Voltage drop, undershoot, and voltage fluctuation are analyzed under the load change. • Optimal air stoichiometry and air excess ratio are suggested for stable operation. - Abstract: The transient response of a proton exchange membrane fuel cell (PEMFC) is an important issue for transportation applications. The objective of this study is to investigate the effects of operating and controlling parameters on the transient response of a PEMFC for achieving more stable cell performance under load change conditions. The transient response of a PEMFC was measured and analyzed by varying air stoichiometry, air humidity, and air excess ratio (AER). The optimal air stoichiometry and AER were determined to minimize the voltage drop, undershoot, and voltage fluctuation under the load change, while maintaining high cell performance. Based on the present data, the optimal air stoichiometry was determined to be between 2.0 and 2.5, and the optimal AER was suggested to be between 1.65 and 2.0

  19. Response of Microbial Community Function to Fluctuating Geochemical Conditions within a Legacy Radioactive Waste Trench Environment.

    Science.gov (United States)

    Vázquez-Campos, Xabier; Kinsela, Andrew S; Bligh, Mark W; Harrison, Jennifer J; Payne, Timothy E; Waite, T David

    2017-09-01

    During the 1960s, small quantities of radioactive materials were codisposed with chemical waste at the Little Forest Legacy Site (Sydney, Australia) in 3-meter-deep, unlined trenches. Chemical and microbial analyses, including functional and taxonomic information derived from shotgun metagenomics, were collected across a 6-week period immediately after a prolonged rainfall event to assess the impact of changing water levels upon the microbial ecology and contaminant mobility. Collectively, results demonstrated that oxygen-laden rainwater rapidly altered the redox balance in the trench water, strongly impacting microbial functioning as well as the radiochemistry. Two contaminants of concern, plutonium and americium, were shown to transition from solid-iron-associated species immediately after the initial rainwater pulse to progressively more soluble moieties as reducing conditions were enhanced. Functional metagenomics revealed the potentially important role that the taxonomically diverse microbial community played in this transition. In particular, aerobes dominated in the first day, followed by an increase of facultative anaerobes/denitrifiers at day 4. Toward the mid-end of the sampling period, the functional and taxonomic profiles depicted an anaerobic community distinguished by a higher representation of dissimilatory sulfate reduction and methanogenesis pathways. Our results have important implications to similar near-surface environmental systems in which redox cycling occurs. IMPORTANCE The role of chemical and microbiological factors in mediating the biogeochemistry of groundwaters from trenches used to dispose of radioactive materials during the 1960s is examined in this study. Specifically, chemical and microbial analyses, including functional and taxonomic information derived from shotgun metagenomics, were collected across a 6-week period immediately after a prolonged rainfall event to assess how changing water levels influence microbial ecology and

  20. Soybean growth responses to enhanced levels of ultraviolet-B radiation under greenhouse conditions

    International Nuclear Information System (INIS)

    Teramura, A.H.; Sullivan, J.H.

    1987-01-01

    Soybean (Glycine max [L.] Merr. cv. Essex) was grown in an unshaded greenhouse under three levels of biologically effective ultraviolet-B (UV-BBE) radiation (effective daily dose: 0, 11.5 and 13.6 kJ m -2 ) for 91 days. Plants were harvested at regular intervals beginning 10 days after germination until reproductive maturity. Mathematical growth analysis revealed that the effects of UV-B radiation varied with plant growth stage. The transition period between vegetative and reproductive growth was the most sensitive to UV-B radiation. Intermediate levels of UV-B had deleterious effects on plant height, leaf area, and total plant dry weight at late vegetative and reproductive stages of development. Specific leaf weight increased during vegetative growth but was unaffected by UV-B during reproductive growth stages. Relative growth, net assimilation, and stem elongation rates were decreased by UV-B radiation during vegetative and early reproductive growth stages. Variation in plant responses may be due in part to changes in microclimate within the plant canopy or to differences in repair or protection mechanisms at differing developmental stages. (author)

  1. Structural response of reactor-core hexcan subassemblies subjected to dynamic overpressurization under accident conditions

    International Nuclear Information System (INIS)

    Pfeiffer, P.A.; Kulak, R.F.

    1993-01-01

    This paper presents a two-dimensional structural analysis for the evaluation of a single core subassembly due to internal overpressure associated with possible failure of fuel pins having high fission gas plenum pressure. Structural models are developed for the subassemblies and their surroundings with emphasis on the critical physical aspects of the problem. With these models the strains, deformations and the extent of permanent damage (plastic strain) to the subassemblies can be assessed. The nonlinear structural analyses was performed with a finite element program called STRAW (Structural Transient Response of Assembly Wrappers). This finite element program is applicable to nonlinear large displacement problems. The results of this study indicate that the permanent deformation (damage) is strongly influenced by the rise time (time to reach peak pressure) of the pressure pulse and the pressure in the fuel pin. The rise time is influenced by the opening time of the flow path for release of gas from the fuel pin plenum. Several examples are illustrated with various rise times and pressure magnitudes and the resulting permanent deformation of the hexcan wall

  2. Speed response of brushless DC motor using fuzzy PID controller under varying load condition

    Directory of Open Access Journals (Sweden)

    Akash Varshney

    2017-09-01

    Full Text Available The increasing trend towards usage of precisely controlled, high torque, efficient and low noise motors for dedicated applications has attracted the attention of researcher in Brushless DC (BLDC motors. BLDC motors can act as an acceptable alternative to the conventional motors like Induction Motors, Switched Reluctance Motors etc. This paper presents a detailed study on the performance of a BLDC motor supplying different types of loads, and at the same time, deploying different control techniques. An advance Fuzzy PID controller is compared with the commonly used PID controller. The load variations considered are of the most common types, generally encountered in practice. A comparison has been carried out in this paper by observing the dynamic speed response of motor at the time of application as well as at the time of removal of the load. The BLDC motors suffer from a major drawback of having jerky behaviour at the time of load removal. The study reveals that irrespective of the type of controller used, the gradual load variation produces better results as against sudden load variations. It is further observed that in addition to other dynamic features, the jerks produced at the time of load removal also get improved to a large extent with Fuzzy PID controller.The speed torque characteristics unraveled the fact that the jerks are minimum at the time of gradual load removal with Fuzzy PID controller in place. An attempt has been made to define these jerks by ‘Perturbation Window’.

  3. Leuconostoc strains isolated from dairy products: Response against food stress conditions.

    Science.gov (United States)

    D'Angelo, Luisa; Cicotello, Joaquín; Zago, Miriam; Guglielmotti, Daniela; Quiberoni, Andrea; Suárez, Viviana

    2017-09-01

    A systematic study about the intrinsic resistance of 29 strains (26 autochthonous and 3 commercial ones), belonging to Leuconostoc genus, against diverse stress factors (thermal, acidic, alkaline, osmotic and oxidative) commonly present at industrial or conservation processes were evaluated. Exhaustive result processing was made by applying one-way ANOVA, Student's test (t), multivariate analysis by Principal Component Analysis (PCA) and Matrix Hierarchical Cluster Analysis. In addition, heat adaptation on 4 strains carefully selected based on previous data analysis was assayed. The strains revealed wide diversity of resistance to stress factors and, in general, a clear relationship between resistance and Leuconostoc species was established. In this sense, the highest resistance was shown by Leuconostoc lactis followed by Leuconostoc mesenteroides strains, while Leuconostoc pseudomesenteroides and Leuconostoc citreum strains revealed the lowest resistance to the stress factors applied. Heat adaptation improved thermal cell survival and resulted in a cross-resistance against the acidic factor. However, all adapted cells showed diminished their oxidative resistance. According to our knowledge, this is the first study regarding response of Leuconostoc strains against technological stress factors and could establish the basis for the selection of "more robust" strains and propose the possibility of improving their performance during industrial processes. Copyright © 2017 Elsevier Ltd. All rights reserved.

  4. Sunna 535-nm photo-fluorescent film dosimeter response to different environmental conditions

    International Nuclear Information System (INIS)

    Murphy, M.K.; Kovacs, A.; McLaughlin, W.L.; Miller, S.D.; Puhl, J.M.

    2003-01-01

    Evaluations on the influence of environmental variabilities on the red fluorescence component of the Sunna Model γ photo-fluorescent dosimeter TM have previously been reported. This present paper describes the environmental effects on the response of the green fluorescence component of the same dosimeter, which is manufactured using the injection molding technique. The results presented include temperature, relative humidity, and light influences both during and after irradiation. The green fluorescence signal shows a significant dependence on irradiation temperature below room temperature at 1%/ deg. C. Above room temperature (approximately 24-60 deg. C), the irradiation temperature effect varies from -0.1%/ deg. C to 1.0%/ deg. C, depending on the absorbed dose level. For facilities with irradiation temperatures between 30 deg. C and 60 deg. C and absorbed dose levels above 10 kGy, irradiation temperature effects are minimal. Light-effects results indicate that the dosimeter is influenced by ultraviolet and blue wavelengths during irradiation as well as during the post-irradiation stabilization period (approximately 22 h), requiring the use of light-tight packaging. Results also show that the dosimeter exhibits negligible effects from ambient moisture during and after irradiation when in the range of 33-95% relative humidity

  5. Urban tree species show the same hydraulic response to vapor pressure deficit across varying tree size and environmental conditions.

    Directory of Open Access Journals (Sweden)

    Lixin Chen

    Full Text Available The functional convergence of tree transpiration has rarely been tested for tree species growing under urban conditions even though it is of significance to elucidate the relationship between functional convergence and species differences of urban trees for establishing sustainable urban forests in the context of forest water relations.We measured sap flux of four urban tree species including Cedrus deodara, Zelkova schneideriana, Euonymus bungeanus and Metasequoia glyptostroboides in an urban park by using thermal dissipation probes (TDP. The concurrent microclimate conditions and soil moisture content were also measured. Our objectives were to examine 1 the influence of tree species and size on transpiration, and 2 the hydraulic control of urban trees under different environmental conditions over the transpiration in response to VPD as represented by canopy conductance. The results showed that the functional convergence between tree diameter at breast height (DBH and tree canopy transpiration amount (E(c was not reliable to predict stand transpiration and there were species differences within same DBH class. Species differed in transpiration patterns to seasonal weather progression and soil water stress as a result of varied sensitivity to water availability. Species differences were also found in their potential maximum transpiration rate and reaction to light. However, a same theoretical hydraulic relationship between G(c at VPD = 1 kPa (G(cref and the G(c sensitivity to VPD (-dG(c/dlnVPD across studied species as well as under contrasting soil water and R(s conditions in the urban area.We concluded that urban trees show the same hydraulic regulation over response to VPD across varying tree size and environmental conditions and thus tree transpiration could be predicted with appropriate assessment of G(cref.

  6. Urban tree species show the same hydraulic response to vapor pressure deficit across varying tree size and environmental conditions.

    Science.gov (United States)

    Chen, Lixin; Zhang, Zhiqiang; Ewers, Brent E

    2012-01-01

    The functional convergence of tree transpiration has rarely been tested for tree species growing under urban conditions even though it is of significance to elucidate the relationship between functional convergence and species differences of urban trees for establishing sustainable urban forests in the context of forest water relations. We measured sap flux of four urban tree species including Cedrus deodara, Zelkova schneideriana, Euonymus bungeanus and Metasequoia glyptostroboides in an urban park by using thermal dissipation probes (TDP). The concurrent microclimate conditions and soil moisture content were also measured. Our objectives were to examine 1) the influence of tree species and size on transpiration, and 2) the hydraulic control of urban trees under different environmental conditions over the transpiration in response to VPD as represented by canopy conductance. The results showed that the functional convergence between tree diameter at breast height (DBH) and tree canopy transpiration amount (E(c)) was not reliable to predict stand transpiration and there were species differences within same DBH class. Species differed in transpiration patterns to seasonal weather progression and soil water stress as a result of varied sensitivity to water availability. Species differences were also found in their potential maximum transpiration rate and reaction to light. However, a same theoretical hydraulic relationship between G(c) at VPD = 1 kPa (G(cref)) and the G(c) sensitivity to VPD (-dG(c)/dlnVPD) across studied species as well as under contrasting soil water and R(s) conditions in the urban area. We concluded that urban trees show the same hydraulic regulation over response to VPD across varying tree size and environmental conditions and thus tree transpiration could be predicted with appropriate assessment of G(cref).

  7. Stress responses of Calluna vulgaris to reduced and oxidised N applied under 'real world conditions'

    International Nuclear Information System (INIS)

    Sheppard, Lucy J.; Leith, Ian D.; Crossley, A.; Van Dijk, N.; Fowler, D.; Sutton, M.A.; Woods, C.

    2008-01-01

    Effects and implications of reduced and oxidised N, applied under 'real world' conditions, since May 2002, are reported for Calluna growing on an ombrotrophic bog. Ammonia has been released from a 10 m line source generating monthly concentrations of 180-6 μg m -3 , while ammonium chloride and sodium nitrate are applied in rainwater at nitrate and ammonium concentrations below 4 mM and providing up to 56 kg N ha -1 year -1 above a background deposition of 10 kg N ha -1 year -1 . Ammonia concentrations, >8 μg m -3 have significantly enhanced foliar N concentrations, increased sensitivity to drought, frost and winter desiccation, spring frost damage and increased the incidence of pathogen outbreaks. The mature Calluna bushes nearest the NH 3 source have turned bleached and moribund. By comparison the Calluna receiving reduced and oxidised N in rain has shown no significant visible or stress related effects with no significant increase in N status. - Exposure to NH 3 reduces stress resistance and increases visible damage in mature Calluna

  8. Seed Germination and Physiological Response of Sunflower (Helianthus annuus L. Cultivars under Saline Conditions

    Directory of Open Access Journals (Sweden)

    Carmen BEINSAN

    2018-05-01

    Full Text Available The purpose of the experiment was to highlight the germination of sunflower seeds affected by the presence of saline stress and the identification of tolerant genotypes. The biological material was represented by sunflower cvs. (Helianthus annuus L.: Coril, Select, Santiago and Fundulea-206. To simulate the saline conditions, germination solutions of sodium chloride (NaCl were used with concentrations corresponding to the osmotic pressures -6 and -10 atm and the control seed hydration was performed with distilled water. Determination of seed germination, growth of seedling, percentage of plumules dry matter, chlorophyll content and free proline were performed. The experimental data obtained suppose the existence in the assimilation apparatus of sunflowers seedling subjected to stress a competitive chlorophyll/free proline biosynthesis processes. The experimental results regarding the effect of salinity on seed germination and seedling growth revealed important differences between genotypes. The radicle growth in the germination process were strongly affected by saline excess, with significant differences between cultivars. Saline stress results in significant reductions in the amount of chlorophyll, and high levels of free proline. It can be observed that with the increase of the stress level the percentage of the dry matter increases, indicating an accentuated water deficit.

  9. Nuclear waste shipping container response to severe accident conditions, A brief critique of the modal study

    International Nuclear Information System (INIS)

    Audin, L.

    1990-12-01

    The Modal Study (NUREG/CR-4829) attempts to upgrade the analysis of spent nuclear fuel transportation accidents, and to verify the validity of the present regulatory scheme of cask performance standards as a means to minimize risk. While an improvement over many prior efforts in this area (such as NUREG-0170), it unfortunately fails to create a realistic simulation either of a shipping cask, the severe conditions to which it could be subjected, or the potential damage to the spent fuel cargo during an accident. There are too many deficiencies in its analysis to allow acceptance of its results for the presumed cask design, and many pending changes in new containers, cargoes and shipping patterns will limit applicability of the Modal Study to future shipments. In essence, the Modal Study is a good start, but is too simplistic, incomplete, outdated and open to serious question to be used as the basis for any present-day environmental or risk assessment of spent fuel transportation. It needs to be redone, with peer review during its production and experimental verification of its assumptions, before it has any relevance to the shipments planned to Yucca Mountain. Finally, it must be expanded into a full risk assessment by inputing its radiological release fractions and probabilities into a valid dispersal simulation to properly determine the impact of its results. 51 refs

  10. An experimental study of the response of the Galesville sandstone to simulated CAES conditions

    Energy Technology Data Exchange (ETDEWEB)

    Erikson, R L; Stottlemyre, J A; Smith, R P

    1980-07-01

    The objective of this experimental study was to determine how the mineralogical and physical characteristics of host rock formations are affected by environmental conditions anticipated for compressed air energy storage (CAES) in porous, permeable rock. In this study, Galesville sandstone cores were reacted in autoclave pressure vessels supporting one of four environments: dry air; heated, air-water vapor; heated, nitrogen-water vapor mixtures; and heated, compressed, liquid water. The simulated CAES environments were maintained in autoclave pressure vessels by controlling the following independent variables: temperature, pressure, time, oxygen content, carbon dioxide content, nitrogen content, and liquid volume. The dependent variables studied were: apparent porosity, gas permeability, water permeability, and friability. These variables were measured at ambient temperature and pressure before and after each sandstone sample was reacted in one of the CAES environments. The experiments gave the following results: the Galesville sandstone exhibited excellent stability in dry air at all temperatures tested (50/sup 0/ to 300/sup 0/C); and significant physical alterations occurred in sandstone samples exposed to liquid water above 150/sup 0/C. Samples shielded from dripping water exhibited excellent stability to 300/sup 0/C; sandstone may be a suitable storage media for heated, humid air provided elevated temperature zones are relatively free of mobile liquid water; and observed changes in the physical properties of the rock may have been caused, in part, by the lack of confining stress on the sample. The inability to apply confining pressure is a severe limitation of autoclave experiments.

  11. Proteins involved in biophoton emission and flooding-stress responses in soybean under light and dark conditions.

    Science.gov (United States)

    Kamal, Abu Hena Mostafa; Komatsu, Setsuko

    2016-02-01

    To know the molecular systems basically flooding conditions in soybean, biophoton emission measurements and proteomic analyses were carried out for flooding-stressed roots under light and dark conditions. Photon emission was analyzed using a photon counter. Gel-free quantitative proteomics were performed to identify significant changes proteins using the nano LC-MS along with SIEVE software. Biophoton emissions were significantly increased in both light and dark conditions after flooding stress, but gradually decreased with continued flooding exposure compared to the control plants. Among the 120 significantly identified proteins in the roots of soybean plants, 73 and 19 proteins were decreased and increased in the light condition, respectively, and 4 and 24 proteins were increased and decreased, respectively, in the dark condition. The proteins were mainly functionally grouped into cell organization, protein degradation/synthesis, and glycolysis. The highly abundant lactate/malate dehydrogenase proteins were decreased in flooding-stressed roots exposed to light, whereas the lysine ketoglutarate reductase/saccharopine dehydrogenase bifunctional enzyme was increased in both light and dark conditions. Notably, however, specific enzyme assays revealed that the activities of these enzymes and biophoton emission were sharply increased after 3 days of flooding stress. This finding suggests that the source of biophoton emission in roots might involve the chemical excitation of electron or proton through enzymatic or non-enzymatic oxidation and reduction reactions. Moreover, the lysine ketoglutarate reductase/saccharopine dehydrogenase bifunctional enzyme may play important roles in responses in flooding stress of soybean under the light condition and as a contributing factor to biophoton emission.

  12. Abiotic stress growth conditions induce different responses in kernel iron concentration across genotypically distinct maize inbred varieties

    Science.gov (United States)

    Kandianis, Catherine B.; Michenfelder, Abigail S.; Simmons, Susan J.; Grusak, Michael A.; Stapleton, Ann E.

    2013-01-01

    The improvement of grain nutrient profiles for essential minerals and vitamins through breeding strategies is a target important for agricultural regions where nutrient poor crops like maize contribute a large proportion of the daily caloric intake. Kernel iron concentration in maize exhibits a broad range. However, the magnitude of genotype by environment (GxE) effects on this trait reduces the efficacy and predictability of selection programs, particularly when challenged with abiotic stress such as water and nitrogen limitations. Selection has also been limited by an inverse correlation between kernel iron concentration and the yield component of kernel size in target environments. Using 25 maize inbred lines for which extensive genome sequence data is publicly available, we evaluated the response of kernel iron density and kernel mass to water and nitrogen limitation in a managed field stress experiment using a factorial design. To further understand GxE interactions we used partition analysis to characterize response of kernel iron and weight to abiotic stressors among all genotypes, and observed two patterns: one characterized by higher kernel iron concentrations in control over stress conditions, and another with higher kernel iron concentration under drought and combined stress conditions. Breeding efforts for this nutritional trait could exploit these complementary responses through combinations of favorable allelic variation from these already well-characterized genetic stocks. PMID:24363659

  13. Pavlovian conditioning between co-administered drugs: elicitation of an apomorphine-induced antiparkinsonian response by scopolamine.

    Science.gov (United States)

    Carey, R J

    1991-01-01

    Sprague-Dawley rats with unilateral 6-OHDA substantia nigra lesions were given combined scopolamine (0.5 mg/kg IP) and apomorphine (0.05 mg/kg SC) treatments. In this animal model, scopolamine, when administered separately, induces ipsilateral rotation and apomorphine, contralateral rotation. When these drugs are co-administered at 0.5 mg/kg and 0.05 mg/kg dose levels, respectively, animals rotate in the contralateral direction, creating the opportunity for the stimulus effect of scopolamine to become associated with the response effect of apomorphine. In tests with scopolamine (0.5 mg/kg), animals that previously had scopolamine and apomorphine co-administered rotated contralaterally in the test chamber, thereby behaving as if they had received apomorphine. Thus, scopolamine exhibited a functionally acquired conditioned stimulus (CS) property by eliciting the apomorphine response of contralateral rotation as a conditioned response. This acquired CS property was extinguished with separate scopolamine trials and reacquired following one scopolamine-apomorphine co-administration trial.

  14. Glycyrrhizin Treatment Facilitates Extinction of Conditioned Fear Responses After a Single Prolonged Stress Exposure in Rats.

    Science.gov (United States)

    Lai, Shuhua; Wu, Gangwei; Jiang, Zhixian

    2018-01-01

    Impaired fear memory extinction is widely considered a key mechanism of post-traumatic stress disorder (PTSD). Recent studies have suggested that neuroinflammation after a single prolonged stress (SPS) exposure may play a critical role in the impaired fear memory extinction. Studies have shown that high mobility group box chromosomal protein 1 (HMGB-1) is critically involved in neuroinflammation. However, the role of HMGB-1 underlying the development of impairment of fear memory extinction is still not known. Thus, we examined the levels of HMGB-1 in the basolateral amygdala (BLA) following SPS using Western blot and evaluated the levels of microglia and astrocytes activation in the BLA after SPS using immunohistochemical staining. We then examined the effects of pre-SPS intra-BLA administration of glycyrrhizin, an HMGB1 inhibitor, or LPS-RS, a competitive TLR4 antagonist, on subsequent post-SPS fear extinction. We found that SPS treatment prolonged the extinction of contextual fear memory after the SPS. The impairment of SPS-induced extinction of contextual fear memory was associated with increased HMGB1 and Toll-like receptor 4 (TLR4) levels in the BLA. Additionally, the impairment of SPS-induced extinction of contextual fear memory was associated with increased activation of microglia and astrocyte in the BLA. Intra-BLA administrations of glycyrrhizin (HMGB-1 inhibitor) or LPS-RS (TLR4 antagonist) can prevent the development of SPS-induced fear extinction impairment. Taken together, these results suggested that SPS treatment may not only produce short term effects on the HMGB1/TLR4-mediated pro-inflammation, but alter the response of microglia and astrocytes to the exposure to fear associated contextual stimuli. © 2018 The Author(s). Published by S. Karger AG, Basel.

  15. Glycyrrhizin Treatment Facilitates Extinction of Conditioned Fear Responses After a Single Prolonged Stress Exposure in Rats

    Directory of Open Access Journals (Sweden)

    Shuhua Lai

    2018-03-01

    Full Text Available Background/Aims: Impaired fear memory extinction is widely considered a key mechanism of post-traumatic stress disorder (PTSD. Recent studies have suggested that neuroinflammation after a single prolonged stress (SPS exposure may play a critical role in the impaired fear memory extinction. Studies have shown that high mobility group box chromosomal protein 1 (HMGB-1 is critically involved in neuroinflammation. However, the role of HMGB-1 underlying the development of impairment of fear memory extinction is still not known. Methods: Thus, we examined the levels of HMGB-1 in the basolateral amygdala (BLA following SPS using Western blot and evaluated the levels of microglia and astrocytes activation in the BLA after SPS using immunohistochemical staining. We then examined the effects of pre-SPS intra-BLA administration of glycyrrhizin, an HMGB1 inhibitor, or LPS-RS, a competitive TLR4 antagonist, on subsequent post-SPS fear extinction. Results: We found that SPS treatment prolonged the extinction of contextual fear memory after the SPS. The impairment of SPS-induced extinction of contextual fear memory was associated with increased HMGB1 and Toll-like receptor 4 (TLR4 levels in the BLA. Additionally, the impairment of SPS-induced extinction of contextual fear memory was associated with increased activation of microglia and astrocyte in the BLA. Intra-BLA administrations of glycyrrhizin (HMGB-1 inhibitor or LPS-RS (TLR4 antagonist can prevent the development of SPS-induced fear extinction impairment. Conclusion: Taken together, these results suggested that SPS treatment may not only produce short term effects on the HMGB1/TLR4-mediated pro-inflammation, but alter the response of microglia and astrocytes to the exposure to fear associated contextual stimuli.

  16. Response of wheat varieties to different nitrogen levels under agro-climatic conditions of mansehra

    International Nuclear Information System (INIS)

    Shahzad, K.; Khan, A.

    2013-01-01

    A field experiment, comprising of three Nitrogen levels viz.0, 60, 120 and 180 kg/ha and five wheat varieties, viz., Pir Sabak-04 (P.S), P.S-05, P.S-08, Atta Habib and Siran, was conducted at Agricultural Research Station, Baffa, Mansehra, in 2011. The experiment was laid out in randomised complete block design with split-plot arrangement. The results indicated that varieties and nitrogen levels were significantly different for tillers per m2, days to physiological maturity, plant height (cm), spike length, grains per spike, 1000 grains weight (gm), biological yield (kg/ha) and grain yield (kg/ha), while harvest index (%) was significantly affected by varieties only. Maximum tillers per m2 were produced in varieties P.S-2008, P.S-2004 and P.S-2005. Maximum days to physiological maturity and grains per spike were observed in variety P.S-2008. Taller plants were produced by variety P.S. 2005. Longer spikes, maximum thousand grains weight and grain yield (kg/ha) were obtained in varieties P.S-2008 and Atta Habib, respectively. Maximum biological yield (kg/ha) was recorded in Atta Habib. Among nitrogen levels, maximum tillers per m2, days to physiological maturity, longer spikes, number of grains per spike, thousand grains weight, biological yield and grain yield were maximum when N was applied at the rate of 120 kg/ha. Similarly the interactive response of varieties and nitrogen was significantly affected for days to emergence, grains per spike, biological yield, grain yield and harvest index (%). From the study, it was concluded that the varieties, Pir Sabak-2008 and Atta Habib, produced maximum seed yield whereas nitrogen applied at the rate of 120 kg/ha performed better in productivity than other treatments. (author)

  17. Simulating the vegetation response in western Europe to abrupt climate changes under glacial background conditions

    Directory of Open Access Journals (Sweden)

    M.-N. Woillez

    2013-03-01

    Full Text Available The last glacial period has been punctuated by two types of abrupt climatic events, the Dansgaard–Oeschger (DO and Heinrich (HE events. These events, recorded in Greenland ice and in marine sediments, involved changes in the Atlantic Meridional Overturning Circulation (AMOC and led to major changes in the terrestrial biosphere. Here we use the dynamical global vegetation model ORCHIDEE to simulate the response of vegetation to abrupt changes in the AMOC strength. We force ORCHIDEE offline with outputs from the IPSL_CM4 general circulation model, in which the AMOC is forced to change by adding freshwater fluxes in the North Atlantic. We investigate the impact of a collapse and recovery of the AMOC, at different rates, and focus on Western Europe, where many pollen records are available for comparison. The impact of an AMOC collapse on the European mean temperatures and precipitations simulated by the GCM is relatively small but sufficient to drive an important regression of forests and expansion of grasses in ORCHIDEE, in qualitative agreement with pollen data for an HE event. On the contrary, a run with a rapid shift of the AMOC to a hyperactive state of 30 Sv, mimicking the warming phase of a DO event, does not exhibit a strong impact on the European vegetation compared to the glacial control state. For our model, simulating the impact of an HE event thus appears easier than simulating the abrupt transition towards the interstadial phase of a DO. For both a collapse or a recovery of the AMOC, the vegetation starts to respond to climatic changes immediately but reaches equilibrium about 200 yr after the climate equilibrates, suggesting a possible bias in the climatic reconstructions based on pollen records, which assume equilibrium between climate and vegetation. However, our study does not take into account vegetation feedbacks on the atmosphere.

  18. Intra-ligamentary autologous conditioned plasma and healing response to treat partial ACL ruptures.

    Science.gov (United States)

    Koch, Matthias; Matteo, Berardo Di; Eichhorn, Jürgen; Zellner, Johannes; Mayr, Felix; Krutsch, Werner; Achenbach, Leonard; Woehl, Rebecca; Nerlich, Michael; Angele, Peter

    2018-05-01

    Conservative treatment of partial ACL ruptures is associated with a high failure rate, and often patients undergo ACL reconstruction. ACL preservation by trephination of the ACL origin and application of Autologous Conditioned Plasma (ACP) seems to be an intriguing new treatment option to favour ACL tissue healing and avoid traditional reconstruction. The aim of this study was to describe the mid-term outcomes of this new ACL preserving technique. Twenty-four patients (mean age 41.8 years) affected by partial rupture of one or both ACL bundles were included in the present trial. The partial ACL tears were arthroscopically assessed and classified according to a new five step grading system. All patients were treated by trephination of the femoral ACL stump and intra-ligamentary application of ACP. The postoperative outcome was evaluated by both subjective scores and stability testing up to a mean of 25.1 months' follow-up. Adverse events and failure rate were also documented. Clinical outcome was good to excellent with IKDC subjective 82.7 (SD 11.8), Lysholm 87.6 (SD 8.1), Tegner 5.3 (SD 2.1), Cincinnati 88.7 (SD 14.8). The failure rate (i.e. persisting knee instability assessed clinically or by rolimeter) was 12.5%. At objective measurements, knee joints showed a firm endpoint in Lachman test, negative pivot shift phenomenon and a significant reduction in AP-laxity compared to pre-operative status by rolimeter testing (p = 0.002). Return to sport practice was achieved after mean 4.8 months (SD 4.1). ACL stump trephination and concomitant intra-ligamentary application of ACP revealed promising results at mid-term follow-up to treat partial ACL lesions.

  19. The resistance response of sunflower genotypes to black stem disease under controlled conditions

    Directory of Open Access Journals (Sweden)

    Reza DARVISHZADEH

    2010-09-01

    Full Text Available Phoma black stem, caused by Phoma macdonaldii, is one of the most important diseases of sunflower in the world. The sources of resistance to Phoma black stem were investigated. A total of 184 genotypes, including some recombinant inbred lines (RILs, several M6 mutant lines obtained by gamma irradiation of seed of the genotype AS 613, and other genotypes from different countries, were evaluated against an aggressive French isolate (MP6 in controlled conditions. The study was carried out in a randomized complete block design with three replicates. Each replicate consisted of 10–12 seedlings. Twenty μL of spore suspension (106 pycnidiospores mL-1 were deposited on the intersection of the cotyledon petiole and the hypocotyl of sunflower plantlets at the two-leaf stage. The percentage of the area exhibiting disease symptoms was scored on the two cotyledon petioles of each of the plantlets three, five and seven days after inoculation. The disease progress rate (rd, as the slope of the regression line for disease severity against time, was also calculated. Analysis of variance detected significant differences among sunflower genotypes for disease severity 7 days after inoculation,as well as for the disease progress rate. A strong correlation (r=0.96, P<0.01 was found between disease severity 7 days after inoculation and the disease progress rate. The inbred lines F1250/03 (origin: Hungary, M5-54-1, M6-862-1 (mutant lines, SDR 18 (origin: USA and two wild Helianthus accessions, 1012 Nebraska and 211 Illinois, (wild type were highly resistant to Phoma black stem. These findings will assist breeders in choosing parent plants for breeding durable resistance to Phoma black stem.

  20. Growth response of Casuarina equisetifolia Forst. rooted stem cuttings to Frankia in nursery and field conditions.

    Science.gov (United States)

    Karthikeyan, A; Chandrasekaran, K; Geetha, M; Kalaiselvi, R

    2013-11-01

    Casuarina equisetifolia Forst. is a tree crop that provides fuel wood, land reclamation, dune stabilization, and scaffolding for construction, shelter belts, and pulp and paper production. C. equisetifolia fixes atmospheric nitrogen through a symbiotic relationship with Frankia, a soil bacterium of the actinobacteria group. The roots of C. equisetifolia produce root nodules where the bacteria fix atmospheric nitrogen, which is an essential nutrient for all plant metabolic activities. However, rooted stem cuttings of elite clones of C. equisetifolia by vegetative propagation is being planted by the farmers of Pondicherry as costeffective method. As the vegetative propagation method uses inert material (vermiculite) for rooting there is no chance for Frankia association. Therefore after planting of these stocks the farmers are applying 150 kg of di-ammonium phosphate (DAP)/acre/year. To overcome this fertilizer usage, the Frankia-inoculated rooted stem cuttings were propagated under nursery conditions and transplanted in the nutrient-deficient soils of Karaikal, Pondicherry (India), in this study. Under nursery experiments the growth and biomass of C. equisetifolia rooted stem cuttings inoculated with Frankia showed 3 times higher growth and biomass than uninoculated control. These stocks were transplanted and monitored for their growth and survival for 1 year in the nutrient-deficient farm land. The results showed that the rooted stem cuttings of C. equisetifolia significantly improved growth in height (8.8 m), stem girth (9.6 cm) and tissue nitrogen content (3.3 mg g-1) than uninoculated controls. The soil nutrient status was also improved due to inoculation of Frankia.

  1. Response to storm conditions of two different beaches at the Mediterranean coast of Morocco

    Science.gov (United States)

    El Mrini, Aldelmounim; Anfuso, Giorgio; Nachite, Driss; Taaouati, Mohamed

    2010-05-01

    In recent decades the increased demand for the recreational use of beaches has resulted in the uptake of studies on the morphodynamic processes which are acting on beaches. This knowledge is fundamental for appropriate coastal erosion management, suitable tourist use of littoral and for the design and shape of human construction. The Mediterranean sectors of Moroccan littoral investigated in this study, Ksar Rimal and Cabo Negro beaches, are respectively located north and south of Cabo Negro promontory and, over recent years, have been subject to increasing tourist activity. This has consisted mainly of the construction of two tourist ports (Marina Smir and Kabila), residential developments, hotels and a motorway which runs parallel to the coast, affecting the dune ridges and two lagoons which are of great ecological interest. In detail, the dunes located in the backshore at Ksar Rimal beach, are nowadays occupied by summer houses threaten by coastal retreat. A wide, partially urbanized, backshore is observed at Cabo Negro beach. With the intention of characterize the morphodynamic and seasonal behavior and the response of the studied beaches to storm impact, a beach monitoring program was carried out in the period 2006-2008, with special attention to the February-March 2008 stormy period. On analyzing the information obtained, it was possible to characterize the morphology and sedimentology of the studied beaches, and to calculate beach volumetric variations. Ksar Rimal is an open, exposed beach characterized by an intermediate slope (tan β = 0.10) with medium-coarse sands. The beach showed a reflective beach state characterized by plunging breakers. Small morphological seasonal changes were observed, most important morphological and volumetric variations (about 20 m3/m) taking place after winter storms which usually gave rise to a more dissipative beach profile (tan β = 0.05) characterized by spilling breakers. Beach recovery was quite rapid, usually lasting 2

  2. Water confinement effects in response of fuel assembly to faulted condition loads

    International Nuclear Information System (INIS)

    Shah, S.J.; Brenneman, B.; Williams, G.T.; Strumpel, J.H.

    2004-01-01

    It has been established by other authors that the accelerations of the water confined by the reactor core baffle plates has a significant effect on the responses of all the fuel assemblies during LOCA (loss of coolant accident) or seismic transients. This particular effect is a consequence of the water being essentially incompressible, and thus experiencing the same horizontal accelerations as the imposed baffle plate motions. These horizontal accelerations of the fluid induce lateral pressure gradients that cause horizontal buoyancy forces on any submerged structures. These forces are in the same direction as the baffle accelerations and, for certain frequencies at least, tend to reduce the relative displacements between the fuel and baffle plates. But there is another confinement effect: the imposed baffle plate velocities must also be transmitted to the water. If the fuel assembly grid strips are treated as simple hydro-foils, these horizontal velocity components change the fluid angle of attack on each strip, and thus may induce large horizontal lift forces on each grid in the same direction as the baffle plate velocity. There is a similar horizontal lift due to inclined flow over the rods when axial flow is present. These combined forces appear to reduce the relative displacements between the fuel and baffle plates for any significant axial flow velocity. Modeling this effect is very simple. It was shown in previous papers that the mechanism for the large fuel assembly damping due to axial flow may be the hydrodynamic forces on the grid strips, and that this is very well represented by discrete viscous dampers at each grid elevation. To include the imposed horizontal water velocity effects, on both the grids and rods, these dampers are simply attached to the baffle plate rather than 'ground'. The large flow-induced damping really acts in a relative reference frame rather than an inertial reference frame, and thus it becomes a flow-induced coupling between the

  3. Response of sunflower hybrids to different nitrogen levels for physiological and agronomical traits under field conditions

    International Nuclear Information System (INIS)

    Baig, D.; Abbasi, F.M.; Ahmed, H.; Qamar, M.; Khan, M.A.

    2016-01-01

    such as nitrogen in sunflower crop. It can be deduced that the -1 application of 180 kg N ha can provide the best combination for good yield in sunflower crop under the prevailing humid conditions of Pakistan. (author)

  4. Experimental study on occupant's thermal responses under the non-uniform conditions in vehicle cabin during the heating period

    Science.gov (United States)

    Zhang, Wencan; Chen, Jiqing; Lan, Fengchong

    2014-03-01

    The existing investigations on thermal comfort mostly focus on the thermal environment conditions, especially of the air-flow field and the temperature distributions in vehicle cabin. Less attention appears to direct to the thermal comfort or thermal sensation of occupants, even to the relationship between thermal conditions and thermal sensation. In this paper, a series of experiments were designed and conducted for understanding the non-uniform conditions and the occupant's thermal responses in vehicle cabin during the heating period. To accurately assess the transient temperature distribution in cabin in common daily condition, the air temperature at a number of positions is measured in a full size vehicle cabin under natural winter environment in South China by using a discrete thermocouples network. The occupant body is divided into nine segments, the skin temperature at each segment and the occupant's local thermal sensation at the head, body, upper limb and lower limb are monitored continuously. The skin temperature is observed by using a discrete thermocouples network, and the local thermal sensation is evaluated by using a seven-point thermal comfort survey questionnaire proposed by American Society of Heating, Refrigerating and Air-Conditioning Engineers, Inc(ASHRAE) Standard. The relationship between the skin temperature and the thermal sensation is discussed and regressed by statistics method. The results show that the interior air temperature is highly non-uniform over the vehicle cabin. The locations where the occupants sit have a significant effect on the occupant's thermal responses, including the skin temperature and the thermal sensation. The skin temperature and thermal sensation are quite different between body segments due to the effect of non-uniform conditions, clothing resistance, and the human thermal regulating system. A quantitative relationship between the thermal sensation and the skin temperature at each body segment of occupant in

  5. Biogeochemical Processes Responsible for the Enhanced Transport of Plutonium Under transient Unsaturated Ground Water Conditions

    Energy Technology Data Exchange (ETDEWEB)

    Fred J. Molz, III

    2010-05-28

    To better understand longer-term vadose zone transport in southeastern soils, field lysimeter experiments were conducted at the Savannah River Site (SRS) near Aiken, SC, in the 1980s. Each of the three lysimeters analyzed herein contained a filter paper spiked with different Pu solutions, and they were left exposed to natural environmental conditions (including the growth of annual weed grasses) for 11 years. The resulting Pu activity measurements from each lysimeter core showed anomalous activity distributions below the source, with significant migration of Pu above the source. Such results are not explainable by adsorption phenomena alone. A transient variably saturated flow model with root water uptake was developed and coupled to a soil reactive transport model. Somewhat surprisingly, the fully transient analysis showed results nearly identical to those of a much simpler steady flow analysis performed previously. However, all phenomena studied were unable to produce the upward Pu transport observed in the data. This result suggests another transport mechanism such as Pu uptake by roots and upward transport due to transpiration. Thus, the variably saturated flow and reactive transport model was extended to include uptake and transport of Pu within the root xylem, along with computational methodology and results. In the extended model, flow velocity in the soil was driven by precipitation input along with transpiration and drainage. Water uptake by the roots determined the flow velocity in the root xylem, and this along with uptake of Pu in the transpiration stream drove advection and dispersion of the two Pu species in the xylem. During wet periods with high potential evapotranspiration, maximum flow velocities through the xylem would approached 600 cm/hr, orders of magnitude larger that flow velocities in the soil. Values for parameters and the correct conceptual viewpoint for Pu transport in plant xylem was uncertain. This motivated further experiments devoted

  6. Biogeochemical Processes Responsible for the Enhanced Transport of Plutonium Under transient Unsaturated Ground Water Conditions

    International Nuclear Information System (INIS)

    Molz, Fred J. III

    2010-01-01

    To better understand longer-term vadose zone transport in southeastern soils, field lysimeter experiments were conducted at the Savannah River Site (SRS) near Aiken, SC, in the 1980s. Each of the three lysimeters analyzed herein contained a filter paper spiked with different Pu solutions, and they were left exposed to natural environmental conditions (including the growth of annual weed grasses) for 11 years. The resulting Pu activity measurements from each lysimeter core showed anomalous activity distributions below the source, with significant migration of Pu above the source. Such results are not explainable by adsorption phenomena alone. A transient variably saturated flow model with root water uptake was developed and coupled to a soil reactive transport model. Somewhat surprisingly, the fully transient analysis showed results nearly identical to those of a much simpler steady flow analysis performed previously. However, all phenomena studied were unable to produce the upward Pu transport observed in the data. This result suggests another transport mechanism such as Pu uptake by roots and upward transport due to transpiration. Thus, the variably saturated flow and reactive transport model was extended to include uptake and transport of Pu within the root xylem, along with computational methodology and results. In the extended model, flow velocity in the soil was driven by precipitation input along with transpiration and drainage. Water uptake by the roots determined the flow velocity in the root xylem, and this along with uptake of Pu in the transpiration stream drove advection and dispersion of the two Pu species in the xylem. During wet periods with high potential evapotranspiration, maximum flow velocities through the xylem would approached 600 cm/hr, orders of magnitude larger that flow velocities in the soil. Values for parameters and the correct conceptual viewpoint for Pu transport in plant xylem was uncertain. This motivated further experiments devoted

  7. Genome-wide Differences in DNA Methylation Changes in Two Contrasting Rice Genotypes in Response to Drought Conditions

    Directory of Open Access Journals (Sweden)

    Wensheng Wang

    2016-11-01

    Full Text Available Differences in drought stress tolerance within diverse rice genotypes have been attributed to genetic diversity and epigenetic alterations. DNA methylation is an important epigenetic modification that influences diverse biological processes, but its effects on rice drought stress tolerance are poorly understood. In this study, methylated DNA immunoprecipitation sequencing and an Affymetrix GeneChip rice genome array were used to profile the DNA methylation patterns and transcriptomes of the drought-tolerant introgression line DK151 and its drought-sensitive recurrent parent IR64 under drought and control conditions. The introgression of donor genomic DNA induced genome-wide DNA methylation changes in DK151 plants. A total of 1190 differentially methylated regions (DMRs were detected between the two genotypes under normal growth conditions, and the DMR-associated genes in DK151 plants were mainly related to stress response, programmed cell death, and nutrient reservoir activity, which are implicated to constitutive drought stress tolerance. A comparison of the DNA methylation changes in the two genotypes under drought conditions indicated that DK151 plants have a more stable methylome, with only 92 drought-induced DMRs, than IR64 plants with 506 DMRs. Gene ontology analyses of the DMR-associated genes in drought-stressed plants revealed that changes to the DNA methylation status of genotype-specific genes are associated with the epigenetic regulation of drought stress responses. Transcriptome analysis further helped to identify a set of 12 and 23 DMR-associated genes that were differentially expressed in DK151 and IR64, respectively, under drought stress compared with respective controls. Correlation analysis indicated that DNA methylation has various effects on gene expression, implying that it affects gene expression directly or indirectly through diverse regulatory pathways. Our results indicate that drought-induced alterations to DNA

  8. Relationship between serum adiponectin concentration, body condition score, and peripheral tissue insulin response of dairy cows during the dry period.

    Science.gov (United States)

    De Koster, J; Urh, C; Hostens, M; Van den Broeck, W; Sauerwein, H; Opsomer, G

    2017-04-01

    The aim of the present study was to describe the relationship between serum adiponectin concentration and peripheral tissue insulin response in dairy cows with a variable body condition score (BCS) during the dry period. Cows were selected at the beginning of the dry period based on BCS (BCS 3.75, n = 5). Animals were followed from the beginning of the dry period by weekly blood sampling and assessment of BCS and backfat thickness. Weekly blood samples were analyzed for adiponectin concentration using a bovine specific ELISA. Hyperinsulinemic euglycemic clamp tests were performed at the end of the dry period to measure peripheral tissue insulin response. Insulin dose response curves were established for both glucose and fatty acid metabolism. Regression analysis revealed that the serum concentrations of adiponectin dropped at the end of the dry period (P insulin responsiveness (reflecting the maximal effect of insulin; r = 0.76, P insulin sensitivity (reflecting the insulin concentration needed to achieve halfmaximal effect; r = -0.54, P = 0.13). At the level of the fatty acid metabolism, greater adiponectin concentrations were negatively correlated with lower NEFA levels during the HEC test reflecting the insulin responsiveness of the NEFA metabolism (r = -0.61, P = 0.08), whereas there was no association with the insulin sensitivity of the NEFA metabolism (r = -0.16, P = 0.67). In conclusion, serum concentrations of adiponectin were negatively associated with the BCS of dairy cows during the dry period and positively associated with insulin responsiveness of the glucose and fatty acid metabolism. Copyright © 2016 Elsevier Inc. All rights reserved.

  9. Comparison of Damage Models for Predicting the Non-Linear Response of Laminates Under Matrix Dominated Loading Conditions

    Science.gov (United States)

    Schuecker, Clara; Davila, Carlos G.; Rose, Cheryl A.

    2010-01-01

    Five models for matrix damage in fiber reinforced laminates are evaluated for matrix-dominated loading conditions under plane stress and are compared both qualitatively and quantitatively. The emphasis of this study is on a comparison of the response of embedded plies subjected to a homogeneous stress state. Three of the models are specifically designed for modeling the non-linear response due to distributed matrix cracking under homogeneous loading, and also account for non-linear (shear) behavior prior to the onset of cracking. The remaining two models are localized damage models intended for predicting local failure at stress concentrations. The modeling approaches of distributed vs. localized cracking as well as the different formulations of damage initiation and damage progression are compared and discussed.

  10. The Mycoplasma hyopneumoniae recombinant heat shock protein P42 induces an immune response in pigs under field conditions.

    Science.gov (United States)

    Jorge, Sérgio; de Oliveira, Natasha Rodrigues; Marchioro, Silvana Beutinger; Fisch, Andressa; Gomes, Charles Klazer; Hartleben, Cláudia Pinho; Conceição, Fabricio Rochedo; Dellagostin, Odir Antonio

    2014-09-01

    Enzootic pneumonia (EP), resulting from Mycoplasma hyopneumoniae infection is one of the most prevalent diseases in pigs and is a major cause of economic losses to the swine industry worldwide. EP is often controlled by vaccination with inactivated, adjuvanted whole-cell bacterin. However, these bacterins provide only partial protection and do not prevent M. hyopneumoniae colonization. Attempts to develop vaccines that are more efficient have made use of the recombinant DNA technology. The objective of this study was to assess the potential of recombinant M. hyopneumoniae heat shock protein P42 in vaccine preparations against EP, using piglets housed under field conditions in a M. hyopneumoniae-positive farm. The cellular and humoral immune responses were elicited after a single intramuscular inoculation of rP42 in an oil-based adjuvant, or in conjunction with whole-cell vaccine preparation. The production of INF-γ and IL-10 cytokines was quantified in the supernatant of the cultured mononuclear cells. The rP42 emulsified in oil-based adjuvant was able to trigger a strong humoral immune response. Further, it induced a cellular immune response, accompanied by the production of antibodies that reacted with the native M. hyopneumoniae protein. The rP42 mediated induction of cellular and humoral immune response in the host suggests that rP42 emulsified in an oil-based adjuvant holds promise as an effective recombinant subunit vaccine against EP. Copyright © 2014 Elsevier Ltd. All rights reserved.

  11. Optimizing the conditions for hydrothermal liquefaction of barley straw for bio-crude oil production using response surface methodology

    DEFF Research Database (Denmark)

    Zhu, Zhe; Rosendahl, Lasse Aistrup; Toor, Saqib Sohail

    2018-01-01

    The present paper examines the conversion of barley straw to bio-crude oil (BO) via hydrothermal liquefaction. Response surface methodology based on central composite design was utilized to optimize the conditions of four independent variables including reaction temperature (factor X1, 260-340 oC...... phenols and their derivatives, acids, aromatic hydrocarbon, ketones, N-contained compounds and alcohols, which makes it a promising material in the applications of either bio-fuel or as a phenol substitute in bio-phenolic resins....

  12. ART culture conditions change the probability of mouse embryo gestation through defined cellular and molecular responses.

    Science.gov (United States)

    Schwarzer, Caroline; Esteves, Telma Cristina; Araúzo-Bravo, Marcos J; Le Gac, Séverine; Nordhoff, Verena; Schlatt, Stefan; Boiani, Michele

    2012-09-01

    (low fetal rate), were analyzed in depth using outbred and inbred fertilization schemes. Resultant blastocysts show imbalances of cell lineage composition; culture medium-specific deviation of gene expression (38 genes, ≥ 4-fold) compared with the in vivo pattern; and produce different litter sizes (P ≤ 0.0076) after transfer into fosters. Confounding effects of subfertility, life style and genetic heterogeneity are reduced to a minimum in the mouse model compared with ART patients. This is an animal model study. Mouse embryo responses to human ART media are not transferable 1-to-1 to human development due to structural and physiologic differences between oocytes of the two species. Our data promote awareness that human ART culture media affect embryo development. Effects reported here in the mouse may apply also in human, because no ART medium presently available on the market has been optimized for human embryo development. The mouse embryo assay (MEA), which requires ART media to support at least 80% blastocyst formation, is in need of reform and should be extended to include post-implantation development.

  13. Response characteristics of HPR1000 primary circuit under different working conditions of the atmospheric relief system after SBLOCA

    Energy Technology Data Exchange (ETDEWEB)

    Sui, Danting, E-mail: suidanting@163.com [School of Nuclear Science and Engineering, North China Electric Power University, Beijing (China); Beijing Key Laboratory of Passive Safety Technology for Nuclear Energy, North China Electric Power University, Beijing (China); Lu, Daogang [School of Nuclear Science and Engineering, North China Electric Power University, Beijing (China); Beijing Key Laboratory of Passive Safety Technology for Nuclear Energy, North China Electric Power University, Beijing (China); Shang, Changzhong; Wei, Yuanyuan [China Nuclear Power Design Co., ltd (ShenZhen), Shenzhen (China); Zhang, Xianjie [School of Nuclear Science and Engineering, North China Electric Power University, Beijing (China); Beijing Key Laboratory of Passive Safety Technology for Nuclear Energy, North China Electric Power University, Beijing (China)

    2017-04-01

    Highlights: • Response of HPR1000 under different VDA conditions after SBLOCA was investigated. • Activation of VDA can trigger ACCU SI earlier with a critical point exists. • VDA capability design should compromise the critical point with reactivity feedback. - Abstract: To cope with SBLOCA in absence of High-Head Safety Injection (HHSI) from design of HPR1000, atmospheric relief system (originally named as VDA in French) is uniquely designed to help to trigger Middle Head Safety Injection (MHSI) or Low Head Safety Injection (LHSI) earlier through cooling primary system quickly after SBLOCA. To make the best use of VDA decay heat removal capability, primary and secondary system of HPR1000 was modeled with RELAP5/SCDAP computer code. After steady-state initialization, a cold leg 30 mm break SBLOCA was simulated with six simulation conditions and five additional cases including availability of ACCU, different VDA discharge locations and area. Response characteristics of primary loop under different VDA working conditions are investigated. Pressurizer pressure decreases rapidly to lower level to trigger the reactor scram, VDA activation and accumulator safety injection sequently. Peak cladding temperature is 899.45 K occurring at 222 s, which is far below the safety limit. Activation of VDA can trigger ACCU SI earlier with a critical point, while positive reactivity will be introduced due to negative moderator temperature effect and Doppler effect. Larger VDA discharge capability will introduce larger reactivity feedback, as well as induce lower core level and SG level. It's suggested that VDA discharge condition should be chosen before the critical point, with the compromise with reactivity feedback introduced due to the negative moderator temperature effect.

  14. Response characteristics of HPR1000 primary circuit under different working conditions of the atmospheric relief system after SBLOCA

    International Nuclear Information System (INIS)

    Sui, Danting; Lu, Daogang; Shang, Changzhong; Wei, Yuanyuan; Zhang, Xianjie

    2017-01-01

    Highlights: • Response of HPR1000 under different VDA conditions after SBLOCA was investigated. • Activation of VDA can trigger ACCU SI earlier with a critical point exists. • VDA capability design should compromise the critical point with reactivity feedback. - Abstract: To cope with SBLOCA in absence of High-Head Safety Injection (HHSI) from design of HPR1000, atmospheric relief system (originally named as VDA in French) is uniquely designed to help to trigger Middle Head Safety Injection (MHSI) or Low Head Safety Injection (LHSI) earlier through cooling primary system quickly after SBLOCA. To make the best use of VDA decay heat removal capability, primary and secondary system of HPR1000 was modeled with RELAP5/SCDAP computer code. After steady-state initialization, a cold leg 30 mm break SBLOCA was simulated with six simulation conditions and five additional cases including availability of ACCU, different VDA discharge locations and area. Response characteristics of primary loop under different VDA working conditions are investigated. Pressurizer pressure decreases rapidly to lower level to trigger the reactor scram, VDA activation and accumulator safety injection sequently. Peak cladding temperature is 899.45 K occurring at 222 s, which is far below the safety limit. Activation of VDA can trigger ACCU SI earlier with a critical point, while positive reactivity will be introduced due to negative moderator temperature effect and Doppler effect. Larger VDA discharge capability will introduce larger reactivity feedback, as well as induce lower core level and SG level. It's suggested that VDA discharge condition should be chosen before the critical point, with the compromise with reactivity feedback introduced due to the negative moderator temperature effect.

  15. Effects of BCAA, arginine and carbohydrate combined drink on post-exercise biochemical response and psychological condition.

    Science.gov (United States)

    Hsu, Mei-Chich; Chien, Kuei-Yu; Hsu, Cheng-Chen; Chung, Chia-Jung; Chan, Kuei-Hui; Su, Borcherng

    2011-04-30

    This study investigated the effects of BCAA, arginine and carbohydrate combined beverage (BCAA Drink) on biochemical responses and psychological conditions during recovery after a single bout of exhaustive exercise. Fourteen healthy males were assigned to drink either BCAA Drink (BA trial) or placebo (PL trial) on two sessions separated by 2 weeks. Blood samples of each subject were collected before exercise, 0, 10, 20, 40, 60, 120 min and 24 h after exercise. No significant differences in the levels of lactate, ammonia, creatine kinase and glycerol between the two groups were observed at any of the time points. However, the levels of glucose and insulin were significantly higher in the BA trial as compared to those in the PL trial at the 40 and 60 min recovery points. Furthermore, the testosterone-to-cortisol ratio at the 120 min recovery point was significantly higher in the BA trial as compared to that in the PL trial. The results indicate the occurrence of anabolic response during the recovery period. The benefit of BCAA Drink was also performed by Profile of Mood States to assess the psychological condition. Fatigue score increased immediately at exhaustion in both groups, but the decrease in the fatigue score at 120 min recovery point was significant only in BA trial. These data indicate that a single bout of exhaustive exercise enhanced the feeling of fatigue. The detrimental consequence was reduced by an ingestion of BCAA Drink.

  16. Oxygen Response of the Wine Yeast Saccharomyces cerevisiae EC1118 Grown under Carbon-Sufficient, Nitrogen-Limited Enological Conditions

    Science.gov (United States)

    Aceituno, Felipe F.; Orellana, Marcelo; Torres, Jorge; Mendoza, Sebastián; Slater, Alex W.; Melo, Francisco

    2012-01-01

    Discrete additions of oxygen play a critical role in alcoholic fermentation. However, few studies have quantitated the fate of dissolved oxygen and its impact on wine yeast cell physiology under enological conditions. We simulated the range of dissolved oxygen concentrations that occur after a pump-over during the winemaking process by sparging nitrogen-limited continuous cultures with oxygen-nitrogen gaseous mixtures. When the dissolved oxygen concentration increased from 1.2 to 2.7 μM, yeast cells changed from a fully fermentative to a mixed respirofermentative metabolism. This transition is characterized by a switch in the operation of the tricarboxylic acid cycle (TCA) and an activation of NADH shuttling from the cytosol to mitochondria. Nevertheless, fermentative ethanol production remained the major cytosolic NADH sink under all oxygen conditions, suggesting that the limitation of mitochondrial NADH reoxidation is the major cause of the Crabtree effect. This is reinforced by the induction of several key respiratory genes by oxygen, despite the high sugar concentration, indicating that oxygen overrides glucose repression. Genes associated with other processes, such as proline uptake, cell wall remodeling, and oxidative stress, were also significantly affected by oxygen. The results of this study indicate that respiration is responsible for a substantial part of the oxygen response in yeast cells during alcoholic fermentation. This information will facilitate the development of temporal oxygen addition strategies to optimize yeast performance in industrial fermentations. PMID:23001663

  17. Oxygen response of the wine yeast Saccharomyces cerevisiae EC1118 grown under carbon-sufficient, nitrogen-limited enological conditions.

    Science.gov (United States)

    Aceituno, Felipe F; Orellana, Marcelo; Torres, Jorge; Mendoza, Sebastián; Slater, Alex W; Melo, Francisco; Agosin, Eduardo

    2012-12-01

    Discrete additions of oxygen play a critical role in alcoholic fermentation. However, few studies have quantitated the fate of dissolved oxygen and its impact on wine yeast cell physiology under enological conditions. We simulated the range of dissolved oxygen concentrations that occur after a pump-over during the winemaking process by sparging nitrogen-limited continuous cultures with oxygen-nitrogen gaseous mixtures. When the dissolved oxygen concentration increased from 1.2 to 2.7 μM, yeast cells changed from a fully fermentative to a mixed respirofermentative metabolism. This transition is characterized by a switch in the operation of the tricarboxylic acid cycle (TCA) and an activation of NADH shuttling from the cytosol to mitochondria. Nevertheless, fermentative ethanol production remained the major cytosolic NADH sink under all oxygen conditions, suggesting that the limitation of mitochondrial NADH reoxidation is the major cause of the Crabtree effect. This is reinforced by the induction of several key respiratory genes by oxygen, despite the high sugar concentration, indicating that oxygen overrides glucose repression. Genes associated with other processes, such as proline uptake, cell wall remodeling, and oxidative stress, were also significantly affected by oxygen. The results of this study indicate that respiration is responsible for a substantial part of the oxygen response in yeast cells during alcoholic fermentation. This information will facilitate the development of temporal oxygen addition strategies to optimize yeast performance in industrial fermentations.

  18. Modelling individual differences in the form of Pavlovian conditioned approach responses: a dual learning systems approach with factored representations.

    Directory of Open Access Journals (Sweden)

    Florian Lesaint

    2014-02-01

    Full Text Available Reinforcement Learning has greatly influenced models of conditioning, providing powerful explanations of acquired behaviour and underlying physiological observations. However, in recent autoshaping experiments in rats, variation in the form of Pavlovian conditioned responses (CRs and associated dopamine activity, have questioned the classical hypothesis that phasic dopamine activity corresponds to a reward prediction error-like signal arising from a classical Model-Free system, necessary for Pavlovian conditioning. Over the course of Pavlovian conditioning using food as the unconditioned stimulus (US, some rats (sign-trackers come to approach and engage the conditioned stimulus (CS itself - a lever - more and more avidly, whereas other rats (goal-trackers learn to approach the location of food delivery upon CS presentation. Importantly, although both sign-trackers and goal-trackers learn the CS-US association equally well, only in sign-trackers does phasic dopamine activity show classical reward prediction error-like bursts. Furthermore, neither the acquisition nor the expression of a goal-tracking CR is dopamine-dependent. Here we present a computational model that can account for such individual variations. We show that a combination of a Model-Based system and a revised Model-Free system can account for the development of distinct CRs in rats. Moreover, we show that revising a classical Model-Free system to individually process stimuli by using factored representations can explain why classical dopaminergic patterns may be observed for some rats and not for others depending on the CR they develop. In addition, the model can account for other behavioural and pharmacological results obtained using the same, or similar, autoshaping procedures. Finally, the model makes it possible to draw a set of experimental predictions that may be verified in a modified experimental protocol. We suggest that further investigation of factored representations in

  19. Modelling Individual Differences in the Form of Pavlovian Conditioned Approach Responses: A Dual Learning Systems Approach with Factored Representations

    Science.gov (United States)

    Lesaint, Florian; Sigaud, Olivier; Flagel, Shelly B.; Robinson, Terry E.; Khamassi, Mehdi

    2014-01-01

    Reinforcement Learning has greatly influenced models of conditioning, providing powerful explanations of acquired behaviour and underlying physiological observations. However, in recent autoshaping experiments in rats, variation in the form of Pavlovian conditioned responses (CRs) and associated dopamine activity, have questioned the classical hypothesis that phasic dopamine activity corresponds to a reward prediction error-like signal arising from a classical Model-Free system, necessary for Pavlovian conditioning. Over the course of Pavlovian conditioning using food as the unconditioned stimulus (US), some rats (sign-trackers) come to approach and engage the conditioned stimulus (CS) itself – a lever – more and more avidly, whereas other rats (goal-trackers) learn to approach the location of food delivery upon CS presentation. Importantly, although both sign-trackers and goal-trackers learn the CS-US association equally well, only in sign-trackers does phasic dopamine activity show classical reward prediction error-like bursts. Furthermore, neither the acquisition nor the expression of a goal-tracking CR is dopamine-dependent. Here we present a computational model that can account for such individual variations. We show that a combination of a Model-Based system and a revised Model-Free system can account for the development of distinct CRs in rats. Moreover, we show that revising a classical Model-Free system to individually process stimuli by using factored representations can explain why classical dopaminergic patterns may be observed for some rats and not for others depending on the CR they develop. In addition, the model can account for other behavioural and pharmacological results obtained using the same, or similar, autoshaping procedures. Finally, the model makes it possible to draw a set of experimental predictions that may be verified in a modified experimental protocol. We suggest that further investigation of factored representations in

  20. Modelling individual differences in the form of Pavlovian conditioned approach responses: a dual learning systems approach with factored representations.

    Science.gov (United States)

    Lesaint, Florian; Sigaud, Olivier; Flagel, Shelly B; Robinson, Terry E; Khamassi, Mehdi

    2014-02-01

    Reinforcement Learning has greatly influenced models of conditioning, providing powerful explanations of acquired behaviour and underlying physiological observations. However, in recent autoshaping experiments in rats, variation in the form of Pavlovian conditioned responses (CRs) and associated dopamine activity, have questioned the classical hypothesis that phasic dopamine activity corresponds to a reward prediction error-like signal arising from a classical Model-Free system, necessary for Pavlovian conditioning. Over the course of Pavlovian conditioning using food as the unconditioned stimulus (US), some rats (sign-trackers) come to approach and engage the conditioned stimulus (CS) itself - a lever - more and more avidly, whereas other rats (goal-trackers) learn to approach the location of food delivery upon CS presentation. Importantly, although both sign-trackers and goal-trackers learn the CS-US association equally well, only in sign-trackers does phasic dopamine activity show classical reward prediction error-like bursts. Furthermore, neither the acquisition nor the expression of a goal-tracking CR is dopamine-dependent. Here we present a computational model that can account for such individual variations. We show that a combination of a Model-Based system and a revised Model-Free system can account for the development of distinct CRs in rats. Moreover, we show that revising a classical Model-Free system to individually process stimuli by using factored representations can explain why classical dopaminergic patterns may be observed for some rats and not for others depending on the CR they develop. In addition, the model can account for other behavioural and pharmacological results obtained using the same, or similar, autoshaping procedures. Finally, the model makes it possible to draw a set of experimental predictions that may be verified in a modified experimental protocol. We suggest that further investigation of factored representations in computational

  1. Hydrological Responses of Weather Conditions and Crop Change of Agricultural Area in the Rincon Valley, New Mexico

    Science.gov (United States)

    Ahn, S.; Sheng, Z.; Abudu, S.

    2017-12-01

    Hydrologic cycle of agricultural area has been changing due to the impacts of climate and land use changes (crop coverage changes) in an arid region of Rincon Valley, New Mexico. This study is to evaluate the impacts of weather condition and crop coverage change on hydrologic behavior of agricultural area in Rincon Valley (2,466km2) for agricultural watershed management using a watershed-scale hydrologic model, SWAT (Soil and Water Assessment Tool). The SWAT model was developed to incorporate irrigation of different crops using auto irrigation function. For the weather condition and crop coverage change evaluation, three spatial crop coverages including a normal (2008), wet (2009), and dry (2011) years were prepared using USDA crop data layer (CDL) for fourteen different crops. The SWAT model was calibrated for the period of 2001-2003 and validated for the period of 2004-2006 using daily-observed streamflow data. Scenario analysis was performed for wet and dry years based on the unique combinations of crop coverages and releases from Caballo Reservoir. The SWAT model simulated the present vertical water budget and horizontal water transfer considering irrigation practices in the Rincon Valley. Simulation results indicated the temporal and spatial variability for irrigation and non-irrigation seasons of hydrologic cycle in agricultural area in terms of surface runoff, evapotranspiration, infiltration, percolation, baseflow, soil moisture, and groundwater recharge. The water supply of the dry year could not fully cover whole irrigation period due to dry weather conditions, resulting in reduction of crop acreage. For extreme weather conditions, the temporal variation of water budget became robust, which requires careful irrigation management of the agricultural area. The results could provide guidelines for farmers to decide crop patterns in response to different weather conditions and water availability.

  2. The fertility response to the Great Recession in Europe and the United States: Structural economic conditions and perceived economic uncertainty

    Directory of Open Access Journals (Sweden)

    Chiara Ludovica Comolli

    2017-05-01

    Full Text Available Background: This study further develops Goldstein et al.'s (2013 analysis of the fertility response to the Great Recession in western economies. Objective: The purpose of this paper is to shed light on the fertility reaction to different indicators of the crisis. Beyond the structural labor market conditions, I investigate the dependence of fertility rates on economic policy uncertainty, government financial risk, and consumer confidence. Methods: Following Goldstein et al. (2013, I use log-log models to assess the elasticity of age-, parity-, and education-specific fertility rates to an array of indicators. Besides the inclusion of a wider set of explanatory variables, I include more recent data (2000−2013 and I enlarge the sample to 31 European countries plus the United States. Results: Fertility response to unemployment in some age- and parity-specific groups has been, in more recent years, larger than estimated by Goldstein et al. (2013. Female unemployment has also been significantly reducing fertility rates. Among uncertainty measures, the drop in consumer confidence is strongly related to fertility decline and in Southern European countries the fertility response to sovereign debt risk is comparable to that of unemployment. Economic policy uncertainty is negatively related to TFR even when controlling for unemployment. Conclusions: Theoretical and empirical investigation is needed to develop more tailored measures of economic and financial insecurity and their impact on birth rates. Contribution: The study shows the nonnegligible influence of economic and financial uncertainty on birth rates during the Great Recession in Western economies, over and above that of structural labor market conditions.

  3. Enzymatic Phorbol Esters Degradation using the Germinated Jatropha Curcas Seed Lipase as Biocatalyst: Optimization Process Conditions by Response Surface Methodology

    Directory of Open Access Journals (Sweden)

    Avita Kusuma Wardhani

    2016-10-01

    Full Text Available Utilization of Jatropha curcas seed cake is limited by the presence of phorbol esters (PE, which are the main toxic compound and heat stable. The objective of this research was to optimize the reaction conditions of the enzymatic PE degradation of the defatted Jatropha curcas seed cake (DJSC using the acetone-dried lipase from the germinated Jatropha curcas seeds as a biocatalyst. Response Surface Methodology (RSM using three-factors-three-levels Box-Behnken design was used to evaluate the effects of the reaction time, the ratio of buffer volume to DJSC, and the ratio of enzyme to DJSC on PE degradation. The results showed that the optimum conditions of PE degradation were 29.33 h, 51.11 : 6 (mL/g, and 30.10 : 5 (U/g cake for the reaction time, the ratio of buffer volume to DJSC, and the ratio of enzyme to DJSC, respectively. The predicted degradation of PE was 98.96% and not significantly different with the validated data of PE degradation. PE content was 0.035 mg/g, in which it was lower than PE in non-toxic Jatropha seeds. The results indicated that enzymatic degradation of PE might be a promising method for degradation of PE.  Copyright © 2016 BCREC GROUP. All rights reserved Received: 22nd December 2015; Revised: 1st April 2016; Accepted: 14th April 2016 How to Cite: Wardhani, A.K., Hidayat, C., Hastuti, P. (2016. Enzymatic Phorbol Esters Degradation using the Germinated Jatropha Curcas Seed Lipase as Biocatalyst: Optimization Process Conditions by Response Surface Methodology. Bulletin of Chemical Reaction Engineering & Catalysis, 11 (3: 346-353 (doi:10.9767/bcrec.11.3.574.346-353 Permalink/DOI: http://doi.org/10.9767/bcrec.11.3.574.346-353

  4. Study on fermentation conditions of palm juice vinegar by response surface methodology and development of a kinetic model

    Directory of Open Access Journals (Sweden)

    S. Ghosh

    2012-09-01

    Full Text Available Natural vinegar is one of the fermented products which has some potentiality with respect to a nutraceutical standpoint. The present study is an optimization of the fermentation conditions for palm juice vinegar production from palm juice (Borassus flabellifer wine, this biochemical process being aided by Acetobacter aceti (NCIM 2251. The physical parameters of the fermentation conditions such as temperature, pH, and time were investigated by Response Surface Methodology (RSM with 2³ factorial central composite designs (CCD. The optimum pH, temperature and time were 5.5, 30 °C and 72 hrs for the highest yield of acetic acid (68.12 g / L. The quadratic model equation had a R² value of 0.992. RSM played an important role in elucidating the basic mechanisms in a complex situation, thus providing better process control by maximizing acetic acid production with the respective physical parameters. At the optimized conditions of temperature, pH and time and with the help of mathematical kinetic equations, the Monod specific growth rate ( µ max= 0.021 h-1, maximum Logistic specific growth rate ( µ 'max = 0.027 h-1 and various other kinetic parameters were calculated, which helped in validation of the experimental data. Therefore, the established kinetic models may be applied for the production of natural vinegar by fermentation of low cost palm juice.

  5. Comparison of light and x-ray sensitometric responses of double-emulsion films for different processing conditions

    International Nuclear Information System (INIS)

    Blendl, Christian; Buhr, Egbert

    2001-01-01

    The effects of different film processing conditions on light and x-ray sensitometric responses were compared for a variety of double-emulsion x-ray films. The processing conditions were altered by changes of the developer temperature. Three different exposure variants were applied: x-ray sensitometry using two stepped neutral density attenuators between film and screens, simultaneous double-sided light sensitometry, and single-sided light sensitometry. 13 different types of double-emulsion x-ray films were investigated, among them three asymmetric films. In the special case of exposing the asymmetric films with the single-sided light sensitometer, a method was investigated where each side of the film is exposed at different locations and the sum effect is analyzed. From each sensitometric curve shape two parameters, the logarithmic speed (log S) and the average gradient (G), were evaluated. The results of this study can be summarized as follows: (1) Single-sided and double-sided light sensitometers revealed almost equal changes of log S when the processing conditions are altered. Thus, single-sided light sensitometers can serve as a substitute for double-sided light sensitometers provided that suited exposure methods are used and appropriate sensitometric parameters are evaluated. (2) Light sensitometry quantitatively indicated changes of the film processing that affect the x-ray speed. Hence, light sensitometry is a useful method to monitor changes in film processing

  6. Relationship between the physical and psychosocial conditions of postoperative gastrointestinal cancer patients and their responses to an informational material

    Directory of Open Access Journals (Sweden)

    Michiyo Mizuno

    2017-01-01

    Full Text Available Objective: Postoperative patients with gastrointestinal (GI cancer have multiple adaptation tasks and care needs to improve their quality of life (QOL. Whether their supportive care needs differ according to their physical and psychosocial conditions is unclear. This study investigated patients' (1 physical and psychosocial conditions (QOL, fatigue, anxiety, cognitive plight, and resilience and (2 responses to an informational booklet describing cancer patients' problems and adaptation tasks, and examined the association between the two factors. Methods: A questionnaire survey was conducted to postoperative patients with GI cancer. Results: The mean age of the 69 respondents was 63 years; 59.4% of the respondents were men. Nine patients who did not read the booklet showed high fatigue and cognitive plight and low QOL. The patients (36.2% who chose “I vaguely understood the content” showed low scores for resilience and cognitive plight while those (8.5% who chose “I will deal with my tasks as described in the scenarios” showed high scores for both of these variables. Conclusions: The condition of some patients continued to be highly affected by their cancer. In terms of understanding the contents of the booklet, resilience was significant, and cognitive plight did not necessarily have a negative impact. The provision of information by means of a booklet might not be suitable for patients who are highly affected by their cancer. Patients may need additional support to be able to make good use of the information provided in such a booklet.

  7. Agronomic response of cultivars of chickpea (Cicer arietinum L. under different soil moisture conditions in province Granma

    Directory of Open Access Journals (Sweden)

    Yanitza Meriño Hernández

    2017-07-01

    Full Text Available To objective of evaluate the response of two cultivars of chickpea (Nac-29 and Nac-5 HA under different soil moisture conditions, field research was carried out in productive teaching plot of the University of Granma. Sowing was carried out on November 22, 2014. Two treatments were used: T1 (Control and T2 (varieties of chickpea in water stress with three replicates, distributed in a randomized block design with split plot arrangements (The large plots corresponded to the two moisture conditions and the small plots to varieties. The variables were: length and diameter of pods, number of grains per plant, number of grains per pods, weight of 100 seeds and agricultural yield. The results obtained were statistically processed using the STATISTICA version 8.0 for Windows program and in case of significant differences, a variance analysis was performed using the Tukey Multiple Range test. The results showed that, with the cultivation of the chickpea, better results are obtained when the plants are subjected to water stress conditions.

  8. Effect of melatonin supplementation on plasma vasopressin response to different conditions in rats with hyperthyroidism induced by L-thyroxine.

    Science.gov (United States)

    Mogulkoc, Rasim; Baltaci, Abdulkerim Kasim

    2010-04-09

    The present study was performed to determine how basal, isotonic, hypertonic and hypovolemic conditions affect fluid-electrolyte balance and plasma arginine vasopressin (AVP) levels in rats with experimental hyperthyroidism supplemented with melatonin. The rats were divided into four groups of twenty-four subjects each kept under the following treatments during one month: (1) Controls; (2) treated with L-thyroxine; (3) treated with L-thyroxine and sham melatonin and (4) treated with L-thyroxine and melatonin. After this each group was further subdivided into subgroups that were subject to normal, isotonic, hypertonic and hypovolemic conditions. The plasma AVP, total triiodothyronine (TT(3)), total thyroxine (TT(4)) and melatonin levels were measured in plasma by means of a Phoenix Pharmaceutical RIA test kit. Hematocrit and osmolality levels were also determined. There were significant increases of total T3 and T4 levels in the L-thyroxine treated groups, p<0.001. The AVP levels were also increased in groups 2 and 3, but not so in the rats treated with melatonin (p<0.001), which also showed increased plasma melatonin levels (p<0.001). These results indicate that treatment with L-thyroxine increases stimulated and non-stimulated AVP release that are inhibited by melatonin supplementation. It was also shown that AVP response to hypertonic and hypovolemic conditions was not affected by L-thyroxine treatment and/or L-thyroxine+melatonin treatment. Copyright 2009 Elsevier B.V. All rights reserved.

  9. Optimization of the Conditions for Extraction of Serine Protease from Kesinai Plant (Streblus asper Leaves Using Response Surface Methodology

    Directory of Open Access Journals (Sweden)

    Md. Zaidul Islam Sarker

    2011-11-01

    Full Text Available Response surface methodology (RSM using a central composite design (CCD was employed to optimize the conditions for extraction of serine protease from kesinai (Streblus asper leaves. The effect of independent variables, namely temperature (42.5,47.5, X1, mixing time (2–6 min, X2, buffer content (0–80 mL, X3 and buffer pH (4.5–10.5, X4 on specific activity, storage stability, temperature and oxidizing agent stability of serine protease from kesinai leaves was investigated. The study demonstrated that use of the optimum temperature, mixing time, buffer content and buffer pH conditions protected serine protease during extraction, as demonstrated by low activity loss. It was found that the interaction effect of mixing time and buffer content improved the serine protease stability, and the buffer pH had the most significant effect on the specific activity of the enzyme. The most desirable conditions of 2.5 °C temperature, 4 min mixing time, 40 mL buffer at pH 7.5 was established for serine protease extraction from kesinai leaves.

  10. Response of Barley Double Haploid Lines to the Grain Yield and Morphological Traits under Water Deficit Stress Conditions

    Directory of Open Access Journals (Sweden)

    Maroof Khalily

    2017-04-01

    Full Text Available To study the relationships of grain yield and some of agro-morphological traits in 40 doubled haploid (DH lines along with parental and three check genotypes in a randomized complete block design with two replications under two water regimes (normal and stress were evaluated during 2011-2012 and 2012-2013 growing seasons. Combined analysis of variance showed significant difference for all the traits in terms of the year, water regimes, lines, and and line × year. Comparison of group means, between non-stress and stress conditions, showed that DH lines had the lowest reduction percentage for the number of grains per spike, thousand grain weight, grain yield and biological yield as opposed to check genotypes. The correlation between grain yield with biological yield, harvest index, thousand grain weight, and hectoliter of kernel weight in both conditions, were highly significant and positive. Based on stepwise regression the peduncle length, number of seeds per spike, thousand seed weight, and hectoliter of kernel weight had important effect on increasing seed yield. The result of path analysis showed that these traits had the highest direct effect on grain yield. Based on mean comparisons of morphological characters as well as STI and GMP indices it can be concluded that lines No.11, 13, 14, 24, 29, 30, 35 and 39 were distinguished to be desirable lines for grain yield and their related traits and also tolerant lines in terms of response to drought stress conditions.

  11. Comparison of intraoperative conditions and postoperative inflammatory response and immune response between patients with common bile duct stones undergoing ESBD and EST

    Directory of Open Access Journals (Sweden)

    Kun Zh

    2016-08-01

    Full Text Available Objective: To analyze the differences in intraoperative conditions and postoperative inflammatory response and immune response levels in patients with common bile duct stones undergoing ESBD and EST treatment. Methods: A total of 565 patients with common bile duct stones who underwent ERCP treatment in our hospital from January 2013 to December 2015 were included in the study, patients’ treatment and testing results were analyzed retrospectively, and then patients were divided into the observation group 300 cases that received ESBD treatment and control group 265 cases that received EST treatment. Differences in intraoperative stress levels as well as postoperative inflammation, nutrition-related index and immune response levels were compared between two groups. Results: Intraoperative N, Cor, C-P and NK cell levels of observation group were lower than those of control group, and FT3 level was higher than that of control group; postoperative inflammation-related factors such as IL-6, CRP, PCT, CA19-9 and CEA levels were lower than those of control group, protein nutrition indexes such as TP, Alb, PA, TRF and RBP values were higher than those of control group, and immune indexes such as CD4+, CD4+/CD8+, IgA, IgM and IgG levels were higher than those of control group while CD8+ level was lower than that of control group. Conclusion: ESBD for the treatment of patients with common bile duct stones is better than EST treatment in reducing surgical stress, optimizing postoperative physical status and other aspects.

  12. Response time variability under slow and fast-incentive conditions in children with ASD, ADHD and ASD+ADHD.

    Science.gov (United States)

    Tye, Charlotte; Johnson, Katherine A; Kelly, Simon P; Asherson, Philip; Kuntsi, Jonna; Ashwood, Karen L; Azadi, Bahare; Bolton, Patrick; McLoughlin, Gráinne

    2016-12-01

    Attention deficit hyperactivity disorder (ADHD) and autism spectrum disorder (ASD) show significant behavioural and genetic overlap. Both ADHD and ASD are characterised by poor performance on a range of cognitive tasks. In particular, increased response time variability (RTV) is a promising indicator of risk for both ADHD and ASD. However, it is not clear whether different indices of RTV and changes to RTV according to task conditions are able to discriminate between the two disorders. Children with ASD (n = 19), ADHD (n = 18), ASD + ADHD (n = 29) and typically developing controls (TDC; n = 26) performed a four-choice RT task with slow-baseline and fast-incentive conditions. Performance was characterised by mean RT (MRT), standard deviation of RT (SD-RT), coefficient of variation (CV) and ex-Gaussian distribution measures of Mu, Sigma and Tau. In the slow-baseline condition, categorical diagnoses and trait measures converged to indicate that children with ADHD-only and ASD + ADHD demonstrated increased MRT, SD-RT, CV and Tau compared to TDC and ASD-only. Importantly, greater improvement in MRT, SD-RT and Tau was demonstrated in ADHD and ASD + ADHD from slow-baseline to fast-incentive conditions compared to TDC and ASD-only. Slower and more variable RTs are markers of ADHD compared to ASD and typically developing controls during slow and less rewarding conditions. Energetic factors and rewards improve task performance to a greater extent in children with ADHD compared to children with ASD. These findings suggest that RTV can be distinguished in ASD, ADHD and ASD + ADHD based on the indices of variability used and the conditions in which they are elicited. Further work identifying neural processes underlying increased RTV is warranted, in order to elucidate disorder-specific and disorder-convergent aetiological pathways. © 2016 The Authors. Journal of Child Psychology and Psychiatry published by John Wiley & Sons Ltd on behalf of Association for

  13. The effects of extended nap periods on cognitive, physiological and subjective responses under simulated night shift conditions.

    Science.gov (United States)

    Davy, Jonathan; Göbel, Matthias

    2018-02-01

    Extended nap opportunities have been effective in maintaining alertness in the context of extended night shifts (+12 h). However, there is limited evidence of their efficacy during 8-h shifts. Thus, this study explored the effects of extended naps on cognitive, physiological and perceptual responses during four simulated, 8-h night shifts. In a laboratory setting, 32 participants were allocated to one of three conditions. All participants completed four consecutive, 8-h night shifts, with the arrangements differing by condition. The fixed night condition worked from 22h00 to 06h00, while the nap early group worked from 20h00 to 08h00 and napped between 00h00 and 03h20. The nap late group worked from 00h00 to 12h00 and napped between 04h00 and 07h20. Nap length was limited to 3 hours and 20 minutes. Participants performed a simple beading task during each shift, while also completing six to eight test batteries roughly every 2 h. During each shift, six test batteries were completed, in which the following measures were taken. Performance indicators included beading output, eye accommodation time, choice reaction time, visual vigilance, simple reaction time, processing speed and object recognition, working memory, motor response time and tracking performance. Physiological measures included heart rate and tympanic temperature, whereas subjective sleepiness and reported sleep length and quality while outside the laboratory constituted the self reported measures. Both naps reduced subjective sleepiness but did not alter the circadian and homeostatic-related changes in cognitive and physiological measures, relative to the fixed night condition. Additionally, there was evidence of sleep inertia following each nap, which resulted in transient reductions in certain perceptual cognitive performance measures. The present study suggested that there were some benefits associated with including an extended nap during 8-h night shifts. However, the effects of sleep inertia

  14. Seedling Emergence and Phenotypic Response of Common Bean Germplasm to Different Temperatures under Controlled Conditions and in Open Field

    Directory of Open Access Journals (Sweden)

    Antonio M. DE RON

    2016-08-01

    Full Text Available Rapid and uniform seed germination and seedling emergence under diverse environmental conditions is a desirable characteristic for crops. Common bean genotypes (Phaseolus vulgaris L. differ in their low temperature tolerance regarding growth and yield. Cultivars tolerant to low temperature during the germination and emergence stages and carriers of the grain quality standards demanded by consumers are needed for the success of the bean crop. The objectives of this study were i to screen the seedling emergence and the phenotypic response of bean germplasm under a range of temperatures in controlled chamber and field conditions to display stress-tolerant genotypes with good agronomic performances and yield potential, and ii to compare the emergence of bean seedlings under controlled environment and in open field conditions to assess the efficiency of genebanks standard germination tests for predicting the performance of the seeds in the field. Three trials were conducted with 28 dry bean genotypes in open field and in growth chamber under low, moderate and warm temperature. Morpho-agronomic data were used to evaluate the phenotypic performance of the different genotypes. Cool temperatures resulted in a reduction of the rate of emergence in the bean genotypes, however, emergence and early growth of bean could be under different genetic control and these processes need further research to be suitably modeled. Nine groups arose from the Principal Component Analysis (PCA representing variation in emergence time and proportion of emergence in the controlled chamber and in the open field indicating a trend to lower emergence in large and extra-large seeded genotypes. Screening of seedling emergence and phenotypic response of the bean germplasm under a range of temperatures in controlled growth chambers and under field conditions showed several genotypes, as landraces 272, 501, 593 and the cultivar Borlotto, with stress-tolerance at emergence and high

  15. Seedling Emergence and Phenotypic Response of Common Bean Germplasm to Different Temperatures under Controlled Conditions and in Open Field.

    Science.gov (United States)

    De Ron, Antonio M; Rodiño, Ana P; Santalla, Marta; González, Ana M; Lema, María J; Martín, Isaura; Kigel, Jaime

    2016-01-01

    Rapid and uniform seed germination and seedling emergence under diverse environmental conditions is a desirable characteristic for crops. Common bean genotypes (Phaseolus vulgaris L.) differ in their low temperature tolerance regarding growth and yield. Cultivars tolerant to low temperature during the germination and emergence stages and carriers of the grain quality standards demanded by consumers are needed for the success of the bean crop. The objectives of this study were (i) to screen the seedling emergence and the phenotypic response of bean germplasm under a range of temperatures in controlled chamber and field conditions to display stress-tolerant genotypes with good agronomic performances and yield potential, and (ii) to compare the emergence of bean seedlings under controlled environment and in open field conditions to assess the efficiency of genebanks standard germination tests for predicting the performance of the seeds in the field. Three trials were conducted with 28 dry bean genotypes in open field and in growth chamber under low, moderate, and warm temperature. Morpho-agronomic data were used to evaluate the phenotypic performance of the different genotypes. Cool temperatures resulted in a reduction of the rate of emergence in the bean genotypes, however, emergence and early growth of bean could be under different genetic control and these processes need further research to be suitably modeled. Nine groups arose from the Principal Component Analysis (PCA) representing variation in emergence time and proportion of emergence in the controlled chamber and in the open field indicating a trend to lower emergence in large and extra-large seeded genotypes. Screening of seedling emergence and phenotypic response of the bean germplasm under a range of temperatures in controlled growth chambers and under field conditions showed several genotypes, as landraces 272, 501, 593, and the cultivar Borlotto, with stress-tolerance at emergence, and high yield

  16. Insulin response of the glucose and fatty acid metabolism in dry dairy cows across a range of body condition scores.

    Science.gov (United States)

    De Koster, J; Hostens, M; Van Eetvelde, M; Hermans, K; Moerman, S; Bogaert, H; Depreester, E; Van den Broeck, W; Opsomer, G

    2015-07-01

    The objective of the present research was to determine the insulin response of the glucose and fatty acid metabolism in dry dairy cows with a variable body condition score (BCS). Ten pregnant Holstein Friesian dairy cows (upcoming parity 2 to 5) were selected based on BCS at the beginning of the study (2mo before expected parturition date). During the study, animals were monitored weekly for BCS and backfat thickness and in the last 2wk, blood samples were taken for determination of serum nonesterified fatty acid (NEFA) concentration. Animals underwent a hyperinsulinemic euglycemic clamp test in the third week before the expected parturition date. The hyperinsulinemic euglycemic clamp test consisted of 4 consecutive insulin infusions with increasing insulin doses: 0.1, 0.5, 2, and 5mIU/kg per minute. For each insulin infusion period, a steady state was defined as a period of 30min where no or minor changes of the glucose infusion were necessary to keep the blood glucose concentration constant and near basal levels. During the steady state, the glucose infusion rate [steady state glucose infusion rate (SSGIR) in µmol/kg per minute] and NEFA concentration [steady state NEFA concentration (SSNEFA) in mmol/L] were determined and reflect the insulin response of the glucose and fatty acid metabolism. Dose response curves were created based on the insulin concentrations during the steady state and the SSGIR or SSNEFA. The shape of the dose response curves is determined by the concentration of insulin needed to elicit the half maximal effect (EC50) and the maximal SSGIR or the minimal SSNEFA for the glucose or fatty acid metabolism, respectively. The maximal SSGIR was negatively associated with variables reflecting adiposity of the cows (BCS, backfat thickness, NEFA concentration during the dry period, and absolute weight of the different adipose depots determined after euthanasia and dissection of the different depots), whereas the EC50 of the glucose metabolism was

  17. Cardiac and respiratory responses of rainbow trout, bluegills and brown bullhead catfish during rapid hypoxia and recovery under normoxic conditions

    Energy Technology Data Exchange (ETDEWEB)

    Marvin, Jr, D E; Burton, D T

    1973-01-01

    Heart rate, ventilation rate and routine oxygen consumption were measured in Salmo gairdneri, Lepomis macrochirus and Ictalurus nebulosus during rapid hypoxic stress and recovery under normoxic conditions. Cardiac and respiratory responses during hypoxia were similar to those reported in the literature for teleost fish. Immediate increases in heart rate and ventilation rate occurred in all three species after stress. When the mean heart rate for each species at 1 hr post-stress was compared with its pre-stress rate, differences in recovery patterns were found in all species. During recovery from hypoxia, rapid increases in oxygen consumption, above pre-stress levels, occurred in S. gairdneri and L. macrochirus. No significant differences between pre-stress and post-stress values were found in I. nebulosus.

  18. Optimization of synthesis conditions of PbS thin films grown by chemical bath deposition using response surface methodology

    Energy Technology Data Exchange (ETDEWEB)

    Yücel, Ersin, E-mail: dr.ersinyucel@gmail.com [Department of Physics, Faculty of Arts and Sciences, Mustafa Kemal University, 31034 Hatay (Turkey); Yücel, Yasin; Beleli, Buse [Department of Chemistry, Faculty of Arts and Sciences, Mustafa Kemal University, 31034 Hatay (Turkey)

    2015-09-05

    Highlights: • For the first time, RSM and CCD used for optimization of PbS thin film. • Tri-sodium citrate, deposition time and temperature were independent variables. • PbS thin film band gap value was 2.20 eV under the optimum conditions. • Quality of the film was improved after chemometrics optimization. - Abstract: In this study, PbS thin films were synthesized by chemical bath deposition (CBD) under different deposition parameters. Response surface methodology (RSM) was used to optimize synthesis parameters including amount of tri-sodium citrate (0.2–0.8 mL), deposition time (14–34 h) and deposition temperature (26.6–43.4 °C) for deposition of the films. 5-level-3-factor central composite design (CCD) was employed to evaluate effects of the deposition parameters on the response (optical band gap of the films). The significant level of both the main effects and the interaction are investigated by analysis of variance (ANOVA). The film structures were characterized by X-ray diffractometer (XRD). Morphological properties of the films were studied with a scanning electron microscopy (SEM). The optical properties of the films were investigated using a UV–visible spectrophotometer. The optimum amount of tri-sodium citrate, deposition time and deposition temperature were found to be 0.7 mL, 18.07 h and 30 °C respectively. Under these conditions, the experimental band gap of PbS was 2.20 eV, which is quite good correlation with value (1.98 eV) predicted by the model.

  19. INTUBATIONS CONDITIONS AND HOMODYNAMIC RESPONSES UNDER ANESTHESIA INDUCTION WITH THREE COMBINATION DRUGS: ALFENTANIL- MIDAZOLAM, ALFENTANIL- THIOPENTAL AND ALFENTANIL- KETAMINE

    Directory of Open Access Journals (Sweden)

    H SOLTANI NEZHAD

    2000-03-01

    Full Text Available Background. Administration of alfentanil followed by propofol intravenously (IV without neuromuscular blockage for induction of anesthesia provides adaquate conditions for tracheal intubation. Other hypnotic drugs have not been thoroughly investigated in this regard. The aim of the present study was comparison of intubation conditions and hemodynamic responses of anesthesia induction with alfentanil/midazolam, alfentanil/Na thiopental and alfentanil/ ketamine. Methods. In a clinical trial study one hundred and twenty children were randomly allocated to four groups. Medication in these groups were alfentanil 40 µg/kg+ midazolam 200 µg/kg,alfentanil 40 µg/kg+Na thiopental 6 µg/kg, alfentanil 40 µg/kg+ketamin 2 mg/kg & Na thipental 6 mg/kg+suxamethonium 2 mg/kg (as control group. In all patients the ease of ventilation via face mask, jaw mobility, degree of exposure and position of vocal cords, patient's response to tracheal intubation, duration of time was needed for intubation and hemodynamic changes after intubation were assessed and recorded. Findings. There are significant differences between first three groups (interventional groups for jaw mebility, ventilation, vocal cord visuality, vocal cord position, patient movement during laryngoscopy and mean laryngoscopy time, (P < 0.05. There is significant difference between all groups of nesdonal+alfentanil except for patient movement. There is significant difference between mean SBP and PR before and after intubation in first and third group. Conclusion. Results represent that the group of Alfentanil plus Nesdonal had a better quality of ventilation rather than two other groups. It is recommended that administration of alfentanil plus thiopental combination is preferred in cases that using muscle relaxant is contraindicated.

  20. Optimization of synthesis conditions of PbS thin films grown by chemical bath deposition using response surface methodology

    International Nuclear Information System (INIS)

    Yücel, Ersin; Yücel, Yasin; Beleli, Buse

    2015-01-01

    Highlights: • For the first time, RSM and CCD used for optimization of PbS thin film. • Tri-sodium citrate, deposition time and temperature were independent variables. • PbS thin film band gap value was 2.20 eV under the optimum conditions. • Quality of the film was improved after chemometrics optimization. - Abstract: In this study, PbS thin films were synthesized by chemical bath deposition (CBD) under different deposition parameters. Response surface methodology (RSM) was used to optimize synthesis parameters including amount of tri-sodium citrate (0.2–0.8 mL), deposition time (14–34 h) and deposition temperature (26.6–43.4 °C) for deposition of the films. 5-level-3-factor central composite design (CCD) was employed to evaluate effects of the deposition parameters on the response (optical band gap of the films). The significant level of both the main effects and the interaction are investigated by analysis of variance (ANOVA). The film structures were characterized by X-ray diffractometer (XRD). Morphological properties of the films were studied with a scanning electron microscopy (SEM). The optical properties of the films were investigated using a UV–visible spectrophotometer. The optimum amount of tri-sodium citrate, deposition time and deposition temperature were found to be 0.7 mL, 18.07 h and 30 °C respectively. Under these conditions, the experimental band gap of PbS was 2.20 eV, which is quite good correlation with value (1.98 eV) predicted by the model

  1. Prediction of heat-illness symptoms with the prediction of human vascular response in hot environment under resting condition.

    Science.gov (United States)

    Aggarwal, Yogender; Karan, Bhuwan Mohan; Das, Barsa Nand; Sinha, Rakesh Kumar

    2008-04-01

    The thermoregulatory control of human skin blood flow is vital to maintain the body heat storage during challenges of thermal homeostasis under heat stress. Whenever thermal homeostasis disturbed, the heat load exceeds heat dissipation capacity, which alters the cutaneous vascular responses along with other body physiological variables. Whole body skin blood flow has been calculated from the forearm blood flow. Present model has been designed using electronics circuit simulator (Multisim 8.0, National Instruments, USA), is to execute a series of predictive equations for early prediction of physiological parameters of young nude subjects during resting condition at various level of dry heat stress under almost still air to avoid causalities associated with hot environmental. The users can execute the model by changing the environmental temperature in degrees C and exposure time in minutes. The model would be able to predict and detect the changes in human vascular responses along with other physiological parameters and from this predicted values heat related-illness symptoms can be inferred.

  2. Mechanical and thermo-mechanical response of a lead-core bearing device subjected to different loading conditions

    Directory of Open Access Journals (Sweden)

    Zhelyazov Todor

    2018-01-01

    Full Text Available The contribution is focused on the numerical modelling, simulation and analysis of a lead-core bearing device for passive seismic isolation. An accurate finite element model of a lead-core bearing device is presented. The model is designed to analyse both mechanical and thermo-mechanical responses of the seismic isolator to different loading conditions. Specifically, the mechanical behaviour in a typical identification test is simulated. The response of the lead-core bearing device to circular sinusoidal paths is analysed. The obtained shear displacement – shear force relationship is compared to experimental data found in literature sources. The hypothesis that heating of the lead-core during cyclic loading affects the degrading phenomena in the bearing device is taken into account. Constitutive laws are defined for each material: lead, rubber and steel. Both predefined constitutive laws (in the used general–purpose finite element code and semi-analytical procedures aimed at a more accurate modelling of the constitutive relations are tested. The results obtained by finite element analysis are to be further used to calibrate a macroscopic model of the lead-core bearing device seen as a single-degree-of-freedom mechanical system.

  3. Optimization of conditions for probiotic curd formulation by Enterococcus faecium MTCC 5695 with probiotic properties using response surface methodology.

    Science.gov (United States)

    Ramakrishnan, Vrinda; Goveas, Louella Concepta; Prakash, Maya; Halami, Prakash M; Narayan, Bhaskar

    2014-11-01

    Enterococcus faecium MTCC 5695 possessing potential probiotic properties as well as enterocin producing ability was used as starter culture. Effect of time (12-24 h) and inoculum level (3-7 % v/v) on cell growth, bacteriocin production, antioxidant property, titrable acidity and pH of curd was studied by response surface methodology (RSM). The optimized conditions were 26.48 h and 2.17%v/v inoculum and the second order model validated. Co cultivation studies revealed that the formulated product had the ability to prevent growth of foodborne pathogens that affect keeping quality of the product during storage. The results indicated that application of E. faecium MTCC 5695 along with usage of optimized conditions attributed to the formation of highly consistent well set curd with bioactive and bioprotective properties. Formulated curd with potential probiotic attributes can be used as therapeutic agent for the treatment of foodborne diseases like Traveler's diarrhea and gastroenteritis which thereby help in improvement of bowel health.

  4. Statistical optimization of ultraviolet irradiate conditions for vitamin D₂ synthesis in oyster mushrooms (Pleurotus ostreatus using response surface methodology.

    Directory of Open Access Journals (Sweden)

    Wei-Jie Wu

    Full Text Available Response surface methodology (RSM was used to determine the optimum vitamin D2 synthesis conditions in oyster mushrooms (Pleurotus ostreatus. Ultraviolet B (UV-B was selected as the most efficient irradiation source for the preliminary experiment, in addition to the levels of three independent variables, which included ambient temperature (25-45°C, exposure time (40-120 min, and irradiation intensity (0.6-1.2 W/m2. The statistical analysis indicated that, for the range which was studied, irradiation intensity was the most critical factor that affected vitamin D2 synthesis in oyster mushrooms. Under optimal conditions (ambient temperature of 28.16°C, UV-B intensity of 1.14 W/m2, and exposure time of 94.28 min, the experimental vitamin D2 content of 239.67 µg/g (dry weight was in very good agreement with the predicted value of 245.49 µg/g, which verified the practicability of this strategy. Compared to fresh mushrooms, the lyophilized mushroom powder can synthesize remarkably higher level of vitamin D2 (498.10 µg/g within much shorter UV-B exposure time (10 min, and thus should receive attention from the food processing industry.

  5. Recent advances in modeling and simulation of the exposure and response of tungsten to fusion energy conditions

    Energy Technology Data Exchange (ETDEWEB)

    Marian, Jaime; Becquart, Charlotte S.; Domain, Christophe; Dudarev, Sergei L.; Gilbert, Mark R.; Kurtz, Richard J.; Mason, Daniel R.; Nordlund, Kai; Sand, Andrea E.; Snead, Lance L.; Suzudo, Tomoaki; Wirth, Brian D.

    2017-06-09

    Under the anticipated operating conditions for demonstration magnetic fusion reactors beyond ITER, structural materials will be exposed to unprecedented conditions of irradiation, heat flux, and temperature. While such extreme enviro