Cognitive Neurostimulation: Learning to Volitionally Sustain Ventral Tegmental Area Activation.

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MacInnes, Jeff J; Dickerson, Kathryn C; Chen, Nan-Kuei; Adcock, R Alison

2016-03-16

Activation of the ventral tegmental area (VTA) and mesolimbic networks is essential to motivation, performance, and learning. Humans routinely attempt to motivate themselves, with unclear efficacy or impact on VTA networks. Using fMRI, we found untrained participants' motivational strategies failed to consistently activate VTA. After real-time VTA neurofeedback training, however, participants volitionally induced VTA activation without external aids, relative to baseline, Pre-test, and control groups. VTA self-activation was accompanied by increased mesolimbic network connectivity. Among two comparison groups (no neurofeedback, false neurofeedback) and an alternate neurofeedback group (nucleus accumbens), none sustained activation in target regions of interest nor increased VTA functional connectivity. The results comprise two novel demonstrations: learning and generalization after VTA neurofeedback training and the ability to sustain VTA activation without external reward or reward cues. These findings suggest theoretical alignment of ideas about motivation and midbrain physiology and the potential for generalizable interventions to improve performance and learning. Copyright © 2016 Elsevier Inc. All rights reserved.

The dual orexin/hypocretin receptor antagonist, almorexant, in the ventral tegmental area attenuates ethanol self-administration.

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Subhashini Srinivasan

Full Text Available Recent studies have implicated the hypocretin/orexinergic system in reward-seeking behavior. Almorexant, a dual orexin/hypocretin R(1 and R(2 receptor antagonist, has proven effective in preclinical studies in promoting sleep in animal models and was in Phase III clinical trials for sleep disorders. The present study combines behavioral assays with in vitro biochemical and electrophysiological techniques to elucidate the role of almorexant in ethanol and sucrose intake. Using an operant self-administration paradigm, we demonstrate that systemic administration of almorexant decreased operant self-administration of both 20% ethanol and 5% sucrose. We further demonstrate that intra-ventral tegmental area (VTA infusions, but not intra-substantia nigra infusions, of almorexant reduced ethanol self-administration. Extracellular recordings performed in VTA neurons revealed that orexin-A increased firing and this enhancement of firing was blocked by almorexant. The results demonstrate that orexin/hypocretin receptors in distinct brain regions regulate ethanol and sucrose mediated behaviors.

Functional μ-Opioid-Galanin Receptor Heteromers in the Ventral Tegmental Area.

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Moreno, Estefanía; Quiroz, César; Rea, William; Cai, Ning-Sheng; Mallol, Josefa; Cortés, Antoni; Lluís, Carme; Canela, Enric I; Casadó, Vicent; Ferré, Sergi

2017-02-01

The neuropeptide galanin has been shown to interact with the opioid system. More specifically, galanin counteracts the behavioral effects of the systemic administration of μ-opioid receptor (MOR) agonists. Yet the mechanism responsible for this galanin-opioid interaction has remained elusive. Using biophysical techniques in mammalian transfected cells, we found evidence for selective heteromerization of MOR and the galanin receptor subtype Gal1 (Gal1R). Also in transfected cells, a synthetic peptide selectively disrupted MOR-Gal1R heteromerization as well as specific interactions between MOR and Gal1R ligands: a negative cross talk, by which galanin counteracted MAPK activation induced by the endogenous MOR agonist endomorphin-1, and a cross-antagonism, by which a MOR antagonist counteracted MAPK activation induced by galanin. These specific interactions, which represented biochemical properties of the MOR-Gal1R heteromer, could then be identified in situ in slices of rat ventral tegmental area (VTA) with MAPK activation and two additional cell signaling pathways, AKT and CREB phosphorylation. Furthermore, in vivo microdialysis experiments showed that the disruptive peptide selectively counteracted the ability of galanin to block the dendritic dopamine release in the rat VTA induced by local infusion of endomorphin-1, demonstrating a key role of MOR-Gal1R heteromers localized in the VTA in the direct control of dopamine cell function and their ability to mediate antagonistic interactions between MOR and Gal1R ligands. The results also indicate that MOR-Gal1R heteromers should be viewed as targets for the treatment of opioid use disorders. The μ-opioid receptor (MOR) localized in the ventral tegmental area (VTA) plays a key role in the reinforcing and addictive properties of opioids. With parallel in vitro experiments in mammalian transfected cells and in situ and in vivo experiments in rat VTA, we demonstrate that a significant population of these MORs form

Direct monitoring of dopamine and 5-HT release in substantia nigra and ventral tegmental area in vitro

DEFF Research Database (Denmark)

Rice, M E; Richards, C D; Nedergaard, S

1994-01-01

Fast-scan cyclic voltammetry with carbon fibre microelectrodes was used to detect endogenous dopamine (DA) and 5-hydroxytryptamine (5-HT) release from three distinct regions of guinea-pig mid-brain in vitro: rostral and caudal substantia nigra (SN) and the ventral tegmental area (VTA). Previous...... these regions with in situ electrodes and demonstrates the utility of fast-scan cyclic voltammetry to investigate the mechanisms and possible non-classical functions of somato-dendritic DA release....

Mere Exposure: Preference Change for Novel Drinks Reflected in Human Ventral Tegmental Area.

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Ballard, Ian C; Hennigan, Kelly; McClure, Samuel M

2017-05-01

Preferences for novel stimuli tend to develop slowly over many exposures. Psychological accounts of this effect suggest that it depends on changes in the brain's valuation system. Participants consumed a novel fluid daily for 10 days and underwent fMRI on the first and last days. We hypothesized that changes in activation in areas associated with the dopamine system would accompany changes in preference. The change in activation in the ventral tegmental area (VTA) between sessions scaled with preference change. Furthermore, a network comprising the sensory thalamus, posterior insula, and ventrolateral striatum showed differential connectivity with the VTA that correlated with individual changes in preference. Our results suggest that the VTA is centrally involved in both assigning value to sensory stimuli and influencing downstream regions to translate these value signals into subjective preference. These results have important implications for models of dopaminergic function and behavioral addiction.

Ventral tegmental area dopamine revisited: effects of acute and repeated stress

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Holly, Elizabeth N.; Miczek, Klaus A.

2015-01-01

Aversive events rapidly and potently excite certain dopamine neurons in the ventral tegmental area (VTA), promoting phasic increases in the medial prefrontal cortex and nucleus accumbens. This is in apparent contradiction to a wealth of literature demonstrating that most VTA dopamine neurons are strongly activated by reward and reward-predictive cues while inhibited by aversive stimuli. How can these divergent processes both be mediated by VTA dopamine neurons? The answer may lie within the functional and anatomical heterogeneity of the VTA. We focus on VTA heterogeneity in anatomy, neurochemistry, electrophysiology, and afferent/efferent connectivity. Second, recent evidence for a critical role of VTA dopamine neurons in response to both acute and repeated stress will be discussed. Understanding which dopamine neurons are activated by stress, the neural mechanisms driving the activation, and where these neurons project will provide valuable insight into how stress can promote psychiatric disorders associated with the dopamine system, such as addiction and depression. PMID:26676983

Transcriptomic profiling of the ventral tegmental area and nucleus accumbens in rhesus macaques following long-term cocaine self-administration.

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Vallender, Eric J; Goswami, Dharmendra B; Shinday, Nina M; Westmoreland, Susan V; Yao, Wei-Dong; Rowlett, James K

2017-06-01

The behavioral consequences associated with addiction are thought to arise from drug-induced neuroadaptation. The mesolimbic system plays an important initial role in this process, and while the dopaminergic system specifically has been strongly interrogated, a complete understanding of the broad transcriptomic effects associated with cocaine use remains elusive. Using next generation sequencing approaches, we performed a comprehensive evaluation of gene expression differences in the ventral tegmental area and nucleus accumbens of rhesus macaques that had self-administered cocaine for roughly 100days and saline-yoked controls. During self-administration, the monkeys increased daily consumption of cocaine until almost the maximum number of injections were taken within the first 15min of the one hour session for a total intake of 3mg/kg/day. We confirm the centrality of dopaminergic differences in the ventral tegmental area, but in the nucleus accumbens we see the strongest evidence for an inflammatory response and large scale chromatin remodeling. These findings suggest an expanded understanding of the pathology of cocaine addiction with the potential to lead to the development of alternative treatment strategies. Copyright © 2017 Elsevier B.V. All rights reserved.

Eating-induced dopamine release from mesolimbic neurons is mediated by NMDA receptors in the ventral tegmental area : A dual-probe microdialysis study

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Westerink, BHC; deVries, JB

This study was aimed at identifying the neuronal pathways that mediate the eating-induced increase in the release of dopamine in the nucleus accumbens of the rat brain. For that purpose, a microdialysis probe was implanted in the ventral tegmental area and a second probe was placed in the

Ventral Tegmental Area Dopamine Cell Activation during Male Rat Sexual Behavior Regulates Neuroplasticity and d-Amphetamine Cross-Sensitization following Sex Abstinence.

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Beloate, Lauren N; Omrani, Azar; Adan, Roger A; Webb, Ian C; Coolen, Lique M

2016-09-21

Experience with sexual behavior causes cross-sensitization of amphetamine reward, an effect dependent on a period of sexual reward abstinence. We previously showed that ΔFosB in the nucleus accumbens (NAc) is a key mediator of this cross-sensitization, potentially via dopamine receptor activation. However, the role of mesolimbic dopamine for sexual behavior or cross-sensitization between natural and drug reward is unknown. This was tested using inhibitory designer receptors exclusively activated by designer drugs in ventral tegmental area (VTA) dopamine cells. rAAV5/hSvn-DIO-hm4D-mCherry was injected into the VTA of TH::Cre adult male rats. Males received clozapine N-oxide (CNO) or vehicle injections before each of 5 consecutive days of mating or handling. Following an abstinence period of 7 d, males were tested for amphetamine conditioned place preference (CPP). Next, males were injected with CNO or vehicle before mating or handling for analysis of mating-induced cFos, sex experience-induced ΔFosB, and reduction of VTA dopamine soma size. Results showed that CNO did not affect mating behavior. Instead, CNO prevented sexual experience-induced cross-sensitization of amphetamine CPP, ΔFosB in the NAc and medial prefrontal cortex, and decreases in VTA dopamine soma size. Expression of hm4D-mCherry was specific to VTA dopamine cells and CNO blocked excitation and mating-induced cFos expression in VTA dopamine cells. These findings provide direct evidence that VTA dopamine activation is not required for initiation or performance of sexual behavior. Instead, VTA dopamine directly contributes to increased vulnerability for drug use following loss of natural reward by causing neuroplasticity in the mesolimbic pathway during the natural reward experience. Drugs of abuse act on the neural pathways that mediate natural reward learning and memory. Exposure to natural reward behaviors can alter subsequent drug-related reward. Specifically, experience with sexual behavior

Cognitive emotion regulation enhances aversive prediction error activity while reducing emotional responses.

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Mulej Bratec, Satja; Xie, Xiyao; Schmid, Gabriele; Doll, Anselm; Schilbach, Leonhard; Zimmer, Claus; Wohlschläger, Afra; Riedl, Valentin; Sorg, Christian

2015-12-01

Cognitive emotion regulation is a powerful way of modulating emotional responses. However, despite the vital role of emotions in learning, it is unknown whether the effect of cognitive emotion regulation also extends to the modulation of learning. Computational models indicate prediction error activity, typically observed in the striatum and ventral tegmental area, as a critical neural mechanism involved in associative learning. We used model-based fMRI during aversive conditioning with and without cognitive emotion regulation to test the hypothesis that emotion regulation would affect prediction error-related neural activity in the striatum and ventral tegmental area, reflecting an emotion regulation-related modulation of learning. Our results show that cognitive emotion regulation reduced emotion-related brain activity, but increased prediction error-related activity in a network involving ventral tegmental area, hippocampus, insula and ventral striatum. While the reduction of response activity was related to behavioral measures of emotion regulation success, the enhancement of prediction error-related neural activity was related to learning performance. Furthermore, functional connectivity between the ventral tegmental area and ventrolateral prefrontal cortex, an area involved in regulation, was specifically increased during emotion regulation and likewise related to learning performance. Our data, therefore, provide first-time evidence that beyond reducing emotional responses, cognitive emotion regulation affects learning by enhancing prediction error-related activity, potentially via tegmental dopaminergic pathways. Copyright © 2015 Elsevier Inc. All rights reserved.

Stimulation of the ventral tegmental area increased nociceptive thresholds and decreased spinal dorsal horn neuronal activity in rat.

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Li, Ai-Ling; Sibi, Jiny E; Yang, Xiaofei; Chiao, Jung-Chih; Peng, Yuan Bo

2016-06-01

Deep brain stimulation has been found to be effective in relieving intractable pain. The ventral tegmental area (VTA) plays a role not only in the reward process, but also in the modulation of nociception. Lesions of VTA result in increased pain thresholds and exacerbate pain in several pain models. It is hypothesized that direct activation of VTA will reduce pain experience. In this study, we investigated the effect of direct electrical stimulation of the VTA on mechanical, thermal and carrageenan-induced chemical nociceptive thresholds in Sprague-Dawley rats using our custom-designed wireless stimulator. We found that: (1) VTA stimulation itself did not show any change in mechanical or thermal threshold; and (2) the decreased mechanical and thermal thresholds induced by carrageenan injection in the hind paw contralateral to the stimulation site were significantly reversed by VTA stimulation. To further explore the underlying mechanism of VTA stimulation-induced analgesia, spinal cord dorsal horn neuronal responses to graded mechanical stimuli were recorded. VTA stimulation significantly inhibited dorsal horn neuronal activity in response to pressure and pinch from the paw, but not brush. This indicated that VTA stimulation may have exerted its analgesic effect via descending modulatory pain pathways, possibly through its connections with brain stem structures and cerebral cortex areas.

Multiplexed Neurochemical Signaling by Neurons of the Ventral Tegmental Area

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Barker, David J.; Root, David H.; Zhang, Shiliang; Morales, Marisela

2016-01-01

The ventral tegmental area (VTA) is an evolutionarily conserved structure that has roles in reward-seeking, safety-seeking, learning, motivation, and neuropsychiatric disorders such as addiction and depression. The involvement of the VTA in these various behaviors and disorders is paralleled by its diverse signaling mechanisms. Here we review recent advances in our understanding of neuronal diversity in the VTA with a focus on cell phenotypes that participate in ‘multiplexed’ neurotransmission involving distinct signaling mechanisms. First, we describe the cellular diversity within the VTA, including neurons capable of transmitting dopamine, glutamate or GABA as well as neurons capable of multiplexing combinations of these neurotransmitters. Next, we describe the complex synaptic architecture used by VTA neurons in order to accommodate the transmission of multiple transmitters. We specifically cover recent findings showing that VTA multiplexed neurotransmission may be mediated by either the segregation of dopamine and glutamate into distinct microdomains within a single axon or by the integration of glutamate and GABA into a single axon terminal. In addition, we discuss our current understanding of the functional role that these multiplexed signaling pathways have in the lateral habenula and the nucleus accumbens. Finally, we consider the putative roles of VTA multiplexed neurotransmission in synaptic plasticity and discuss how changes in VTA multiplexed neurons may relate to various psychopathologies including drug addiction and depression. PMID:26763116

Ethanol drinking reduces extracellular dopamine levels in the posterior ventral tegmental area of nondependent alcohol-preferring rats.

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Engleman, Eric A; Keen, Elizabeth J; Tilford, Sydney S; Thielen, Richard J; Morzorati, Sandra L

2011-09-01

Moderate ethanol exposure produces neuroadaptive changes in the mesocorticolimbic dopamine (DA) system in nondependent rats and increases measures of DA neuronal activity in vitro and in vivo. Moreover, moderate ethanol drinking and moderate systemic exposure elevates extracellular DA levels in mesocorticolimbic projection regions. However, the neuroadaptive changes subsequent to moderate ethanol drinking on basal DA levels have not been investigated in the ventral tegmental area (VTA). In the present study, adult female alcohol-preferring (P) rats were divided into alcohol-naive, alcohol-drinking, and alcohol-deprived groups. The alcohol-drinking group had continuous access to water and ethanol (15%, vol/vol) for 8 weeks. The alcohol-deprived group had 6 weeks of access followed by 2 weeks of ethanol deprivation, 2 weeks of ethanol re-exposure, followed again by 2 weeks of deprivation. The deprived rats demonstrated a robust alcohol deprivation effect (ADE) on ethanol reinstatement. The alcohol-naïve group had continuous access to water only. In the last week of the drinking protocol, all rats were implanted with unilateral microdialysis probes aimed at the posterior VTA and no-net-flux microdialysis was conducted to quantify extracellular DA levels and DA clearance. Results yielded significantly lower basal extracellular DA concentrations in the posterior VTA of the alcohol-drinking group compared with the alcohol-naive and alcohol-deprived groups (3.8±0.3nM vs. 5.0±0.5nM [Palcohol-drinking and alcohol-naive groups (72±2% vs. 46±4%, respectively) and not significantly different (P=.051) between alcohol-deprived and alcohol-naive groups (61±6% for the alcohol-deprived group). The data indicate that reductions in basal DA levels within the posterior VTA occur after moderate chronic ethanol intake in nondependent P rats. This reduction may result, in part, from increased DA uptake and may be important for the maintenance of ethanol drinking. These adaptations

Hypocretin 1/orexin A in the ventral tegmental area enhances dopamine responses to cocaine and promotes cocaine self-administration.

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España, Rodrigo A; Melchior, James R; Roberts, David C S; Jones, Sara R

2011-03-01

Recent evidence indicates that the hypocretin/orexin system participates in the regulation of reinforcement and addiction processes. For example, manipulations that decrease hypocretin neurotransmission result in disruptions of neurochemical and behavioral responses to cocaine. To further assess the relationship between the hypocretin system and cocaine reinforcement, the current studies used microdialysis and in vivo voltammetry to examine the effects of hypocretin 1 on cocaine-induced enhancement of dopamine signaling in the nucleus accumbens core. Fixed ratio, discrete trials, and progressive ratio self-administration procedures were also used to assess whether hypocretin 1 promotes cocaine self-administration behavior. Infusions of hypocretin 1 into the ventral tegmental area increased the effects of cocaine on tonic and phasic dopamine signaling and increased the motivation to self-administer cocaine on the discrete trials and progressive ratio schedules. Together with previous observations demonstrating that a hypocretin 1 receptor antagonist disrupts dopamine signaling and reduces self-administration of cocaine, the current observations further indicate that the hypocretin system participates in reinforcement processes likely through modulation of the mesolimbic dopamine system.

Effects of Ascorbic Acid on the Amplitude of Ventral Tegmental Area Field Action Potential in Morphine-Exposed Rats (An Electrophysiology Study

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K Saadipour

2010-07-01

Full Text Available Introduction & Objective: Evidences have indicated that the Ventral Tegmental Area (VTA is the major source of dopamine (DA neurons projecting to cortical and limbic regions involved in cognitive and motivational aspects of addiction. Also, studies have indicated that the Ascorbic acid (vitamin C can reduce the dependency symptoms of opioids such as morphine via effect of activity on dopaminergic neuron in VTA. For this reason, the aim of this study was to assess the effects of ascorbic acid on the amplitude of Ventral Tegmental Area field action potential in morphine-exposed rats. Materials & Methods: Forty male Wistar’s rats were used in this experimental study conducted at Yasuj University of Medical Sciences in 2010. Animals were randomly divided into four groups after electrode implantation and recovery period: 1. No- Vit C and No-Addicted group (nVitC.nA 2. Vit C and No-Addicted group (VitC.nA 3. No- Vit C and Addicted group (nVitCA 4.Vit C and Addicted (VitC.A, The Vit C groups received 500 mg/kg of Vit C during 20 days. For addicted groups morphine was administrated once daily for 20 days. In the 20th day, the field potential recording was accomplished. Two-way ANOVA was used for data analysis followed by the Tukey test for post hoc analysis. Results were considered significant at P < 0.05. Results: This study shows the exposure to morphine declined the power of Delta and Beta bands (p<0.05 and Vit C solely enhance power of Theta and Beta (p<0.05, p<0.001 in VTA nuclei. Furthermore, Vit C could alter power of some bands which were affected by morphine. Therefore it seems that Vit C has an increasing effects on them (p<0.05. Conclusion: Although the effect of Vit C on power of the VTA bands is not well known, but it is supposed that this phenomenon can be related to alteration in activity of dopaminergic neuron in the brain.

Role of dopamine receptors in the ventral tegmental area in conditioned fear.

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de Oliveira, Amanda Ribeiro; Reimer, Adriano Edgar; Brandão, Marcus Lira

2009-05-16

The increased startle reflex in the presence of a stimulus that has been previously paired with footshock has been termed fear-potentiated startle (FPS) and is considered a reliable index of anxiety. Some studies have suggested an association between stressful situations and alterations in dopaminergic (DA) transmission. Many studies converge on the hypothesis that the mesocorticolimbic pathway, originating from DA neurons in the ventral tegmental area (VTA), is particularly sensitive to fear-arousing stimuli. The present study explored the involvement of VTA DA receptors in the acquisition and expression of conditioned fear to a light conditioned stimulus (CS). We evaluated the effects of intra-VTA administration of SKF 38393 (D(1) agonist), SCH 23390 (D(1) antagonist), quinpirole (D(2) agonist), and sulpiride (D(2) antagonist) on FPS. All drugs were administered bilaterally into the VTA (1.0 microg/0.2 microl/site). Locomotor activity/exploration and motor coordination were evaluated in the open-field and rotarod tests. None of the drugs produced significant effects on FPS when injected before conditioning, indicating that VTA DA receptors are not involved in the acquisition of conditioned fear to a light-CS. In contrast, when injected before the test session, quinpirole significantly reduced FPS, whereas the other drugs had no effect. Quinpirole's ability to decrease FPS may be the result of an action on VTA D(2) presynaptic autoreceptors that decrease dopamine levels in terminal fields of the mesocorticolimbic pathway. Altogether, the present results suggest the importance of VTA DA neurons in the fear-activating effects of Pavlovian conditioning. In addition to demonstrating the importance of dopaminergic mechanisms in the motivational consequences of footshock, the present findings also indicate that these neural circuits are mainly involved in the expression, rather than acquisition, of conditioned fear.

Duration of inhibition of ventral tegmental area dopamine neurons encodes a level of conditioned fear.

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Mileykovskiy, Boris; Morales, Marisela

2011-05-18

It is widely accepted that midbrain dopamine (DA) neurons encode actual and expected reward values by phasic alterations in firing rate. However, how DA neurons encode negative events in the environment is still unclear because some DA neurons appear to be depressed and others excited by aversive stimuli. Here, we show that exposing fear-conditioned rats to stimuli predicting electrical shock elicited three types of biphasic responses, each of which contained an inhibitory pause, in neurochemically identified ventral tegmental area (VTA) DA neurons. The duration of the inhibitory pause in these responses of VTA DA neurons was in direct proportion to the increase in respiratory rate reflecting the level of conditioned fear. Our results suggest that the duration of inhibition of VTA DA neurons encodes negative emotional values of signals predicting aversive events in the environment.

Morphine withdrawal enhances constitutive μ-opioid receptor activity in the ventral tegmental area.

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Meye, Frank J; van Zessen, Ruud; Smidt, Marten P; Adan, Roger A H; Ramakers, Geert M J

2012-11-14

μ-Opioid receptors (MORs) in the ventral tegmental area (VTA) are pivotally involved in addictive behavior. While MORs are typically activated by opioids, they can also become constitutively active in the absence of any agonist. In the current study, we present evidence that MOR constitutive activity is highly relevant in the mouse VTA, as it regulates GABAergic input to dopamine neurons. Specifically, suppression of MOR constitutive activity with the inverse agonist KC-2-009 enhanced GABAergic neurotransmission onto VTA dopamine neurons. This inverse agonistic effect was fully blocked by the specific MOR neutral antagonist CTOP, which had no effect on GABAergic transmission itself. We next show that withdrawal from chronic morphine further increases the magnitude of inverse agonistic effects at the MOR, suggesting enhanced MOR constitutive activity. We demonstrate that this increase can be an adaptive response to the detrimental elevation in cAMP levels known to occur during morphine withdrawal. These findings offer important insights in the physiological occurrence and function of MOR constitutive activity, and have important implications for therapeutic strategies aimed at normalizing MOR signaling during addiction and opioid overdose.

Effects of prefrontal cortical inactivation on neural activity in the ventral tegmental area

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Jo, Yong Sang; Lee, Jane; Mizumori, Sheri J.Y.

2013-01-01

Dopamine (DA) cells have been suggested to signal discrepancies between expected and actual rewards in reinforcement learning. DA cells in the ventral tegmental area (VTA) receive direct projections from the medial prefrontal cortex (mPFC), a structure that is known as one of the brain areas that represent expected future rewards. To investigate whether the mPFC contributes to generating reward prediction error signals of DA cells, we recorded VTA cells from rats foraging for different amounts of reward in a spatial working memory task. Our results showed that DA cells initially responded after the acquisition of rewards, but over training, they exhibited phasic responses when rats detected sensory cues originating from the rewards before obtaining them. We also observed two separate groups of non-DA cells that were activated in expectation of upcoming rewards or during reward consumption. Bilateral injections of muscimol, a GABAA agonist, into the mPFC significantly decreased the non-DA activity that encoded reward expectation. By contrast, the same manipulation of the mPFC elevated DA responses to reward-predicting cues. However, neither DA nor non-DA responses that were elicited after reward acquisition were affected by mPFC inactivation. These results suggest that the mPFC provides the information about expected rewards to the VTA, and its functional loss elevates DA responses to reward-predicting cues by altering expectations about forthcoming rewards. PMID:23658156

Salsolinol facilitates glutamatergic transmission to dopamine neurons in the posterior ventral tegmental area of rats.

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Guiqin Xie

Full Text Available Although in vivo evidence indicates that salsolinol, the condensation product of acetaldehyde and dopamine, has properties that may contribute to alcohol abuse, the underlying mechanisms have not been fully elucidated. We have reported previously that salsolinol stimulates dopamine neurons in the posterior ventral tegmental area (p-VTA partly by reducing inhibitory GABAergic transmission, and that ethanol increases glutamatergic transmission to VTA-dopamine neurons via the activation of dopamine D(1 receptors (D(1Rs. In this study, we tested the hypothesis that salsolinol stimulates dopamine neurons involving activation of D(1Rs. By using whole-cell recordings on p-VTA-dopamine neurons in acute brain slices of rats, we found that salsolinol-induced increase in spike frequency of dopamine neurons was substantially attenuated by DL-2-amino-5-phosphono-valeric acid and 6, 7-dinitroquinoxaline-2, 3-dione, the antagonists of glutamatergic N-Methyl-D-aspartic acid and α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptors. Moreover, salsolinol increased the amplitude of evoked excitatory postsynaptic currents (EPSCs and the frequency but not the amplitude of spontaneous EPSCs. Additionally, SKF83566, a D(1R antagonist attenuated the salsolinol-induced facilitation of EPSCs and of spontaneous firing of dopamine neurons. Our data reveal that salsolinol enhances glutamatergic transmission onto dopamine neurons via activation of D(1Rs at the glutamatergic afferents in dopamine neurons, which contributes to salsolinol's stimulating effect on p-VTA dopamine neurons. This appears to be a novel mechanism which contributes toward rewarding properties of salsolinol.

Overexpression of the steroidogenic enzyme cytochrome P450 side chain cleavage in the ventral tegmental area increases 3α,5α-THP and reduces long-term operant ethanol self-administration.

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Cook, Jason B; Werner, David F; Maldonado-Devincci, Antoniette M; Leonard, Maggie N; Fisher, Kristen R; O'Buckley, Todd K; Porcu, Patrizia; McCown, Thomas J; Besheer, Joyce; Hodge, Clyde W; Morrow, A Leslie

2014-04-23

Neuroactive steroids are endogenous neuromodulators capable of altering neuronal activity and behavior. In rodents, systemic administration of endogenous or synthetic neuroactive steroids reduces ethanol self-administration. We hypothesized this effect arises from actions within mesolimbic brain regions that we targeted by viral gene delivery. Cytochrome P450 side chain cleavage (P450scc) converts cholesterol to pregnenolone, the rate-limiting enzymatic reaction in neurosteroidogenesis. Therefore, we constructed a recombinant adeno-associated serotype 2 viral vector (rAAV2), which drives P450scc expression and neuroactive steroid synthesis. The P450scc-expressing vector (rAAV2-P450scc) or control GFP-expressing vector (rAAV2-GFP) were injected bilaterally into the ventral tegmental area (VTA) or nucleus accumbens (NAc) of alcohol preferring (P) rats trained to self-administer ethanol. P450scc overexpression in the VTA significantly reduced ethanol self-administration by 20% over the 3 week test period. P450scc overexpression in the NAc, however, did not alter ethanol self-administration. Locomotor activity was unaltered by vector administration to either region. P450scc overexpression produced a 36% increase in (3α,5α)-3-hydroxypregnan-20-one (3α,5α-THP, allopregnanolone)-positive cells in the VTA, but did not increase 3α,5α-THP immunoreactivity in NAc. These results suggest that P450scc overexpression and the resultant increase of 3α,5α-THP-positive cells in the VTA reduces ethanol reinforcement. 3α,5α-THP is localized to neurons in the VTA, including tyrosine hydroxylase neurons, but not astrocytes. Overall, the results demonstrate that using gene delivery to modulate neuroactive steroids shows promise for examining the neuronal mechanisms of moderate ethanol drinking, which could be extended to other behavioral paradigms and neuropsychiatric pathology.

Estradiol increases the sensitivity of ventral tegmental area dopamine neurons to dopamine and ethanol.

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Bertha J Vandegrift

Full Text Available Gender differences in psychiatric disorders such as addiction may be modulated by the steroid hormone estrogen. For instance, 17β-estradiol (E2, the predominant form of circulating estrogen in pre-menopausal females, increases ethanol consumption, suggesting that E2 may affect the rewarding properties of ethanol and thus the development of alcohol use disorder in females. The ventral tegmental area (VTA is critically involved in the rewarding and reinforcing effects of ethanol. In order to determine the role of E2 in VTA physiology, gonadally intact female mice were sacrificed during diestrus II (high E2 or estrus (low E2 for electrophysiology recordings. We measured the excitation by ethanol and inhibition by dopamine (DA of VTA DA neurons and found that both excitation by ethanol and inhibition by dopamine were greater in diestrus II compared with estrus. Treatment of VTA slices from mice in diestrus II with an estrogen receptor antagonist (ICI 182,780 reduced ethanol-stimulated neuronal firing, but had no effect on ethanol-stimulated firing of neurons in slices from mice in estrus. Surprisingly, ICI 182,780 did not affect the inhibition by DA, indicating different mechanisms of action of estrogen receptors in altering ethanol and DA responses. We also examined the responses of VTA DA neurons to ethanol and DA in ovariectomized mice treated with E2 and found that E2 treatment enhanced the responses to ethanol and DA in a manner similar to what we observed in mice in diestrus II. Our data indicate that E2 modulates VTA neuron physiology, which may contribute to both the enhanced reinforcing and rewarding effects of alcohol and the development of other psychiatric disorders in females that involve alterations in DA neurotransmission.

Orexin–Corticotropin-Releasing Factor Receptor Heteromers in the Ventral Tegmental Area as Targets for Cocaine

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Navarro, Gemma; Quiroz, César; Moreno-Delgado, David; Sierakowiak, Adam; McDowell, Kimberly; Moreno, Estefanía; Rea, William; Cai, Ning-Sheng; Aguinaga, David; Howell, Lesley A.; Hausch, Felix; Cortés, Antonio; Mallol, Josefa; Casadó, Vicent; Lluís, Carme; Canela, Enric I.

2015-01-01

Release of the neuropeptides corticotropin-releasing factor (CRF) and orexin-A in the ventral tegmental area (VTA) play an important role in stress-induced cocaine-seeking behavior. We provide evidence for pharmacologically significant interactions between CRF and orexin-A that depend on oligomerization of CRF1 receptor (CRF1R) and orexin OX1 receptors (OX1R). CRF1R–OX1R heteromers are the conduits of a negative crosstalk between orexin-A and CRF as demonstrated in transfected cells and rat VTA, in which they significantly modulate dendritic dopamine release. The cocaine target σ1 receptor (σ1R) also associates with the CRF1R–OX1R heteromer. Cocaine binding to the σ1R–CRF1R–OX1R complex promotes a long-term disruption of the orexin-A–CRF negative crosstalk. Through this mechanism, cocaine sensitizes VTA cells to the excitatory effects of both CRF and orexin-A, thus providing a mechanism by which stress induces cocaine seeking. PMID:25926444

Orexin-corticotropin-releasing factor receptor heteromers in the ventral tegmental area as targets for cocaine.

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Navarro, Gemma; Quiroz, César; Moreno-Delgado, David; Sierakowiak, Adam; McDowell, Kimberly; Moreno, Estefanía; Rea, William; Cai, Ning-Sheng; Aguinaga, David; Howell, Lesley A; Hausch, Felix; Cortés, Antonio; Mallol, Josefa; Casadó, Vicent; Lluís, Carme; Canela, Enric I; Ferré, Sergi; McCormick, Peter J

2015-04-29

Release of the neuropeptides corticotropin-releasing factor (CRF) and orexin-A in the ventral tegmental area (VTA) play an important role in stress-induced cocaine-seeking behavior. We provide evidence for pharmacologically significant interactions between CRF and orexin-A that depend on oligomerization of CRF1 receptor (CRF1R) and orexin OX1 receptors (OX1R). CRF1R-OX1R heteromers are the conduits of a negative crosstalk between orexin-A and CRF as demonstrated in transfected cells and rat VTA, in which they significantly modulate dendritic dopamine release. The cocaine target σ1 receptor (σ1R) also associates with the CRF1R-OX1R heteromer. Cocaine binding to the σ1R-CRF1R-OX1R complex promotes a long-term disruption of the orexin-A-CRF negative crosstalk. Through this mechanism, cocaine sensitizes VTA cells to the excitatory effects of both CRF and orexin-A, thus providing a mechanism by which stress induces cocaine seeking. Copyright © 2015 the authors 0270-6474/15/356639-15$15.00/0.

Optogenetic Activation of a Lateral Hypothalamic-Ventral Tegmental Drive-Reward Pathway.

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Gigante, Eduardo D; Benaliouad, Faiza; Zamora-Olivencia, Veronica; Wise, Roy A

2016-01-01

Electrical stimulation of the lateral hypothalamus can motivate feeding or can serve as a reward in its own right. It remains unclear whether the same or independent but anatomically overlapping circuitries mediate the two effects. Electrical stimulation findings implicate medial forebrain bundle (MFB) fibers of passage in both effects, and optogenetic studies confirm a contribution from fibers originating in the lateral hypothalamic area and projecting to or through the ventral tegmental area. Here we report that optogenetic activation of ventral tegmental fibers from cells of origin in more anterior or posterior portions of the MFB failed to induce either reward or feeding. The feeding and reward induced by optogenetic activation of fibers from the lateral hypothalamic cells of origin were influenced similarly by variations in stimulation pulse width and pulse frequency, consistent with the hypothesis of a common substrate for the two effects. There were, however, several cases where feeding but not self-stimulation or self-stimulation but not feeding were induced, consistent with the hypothesis that distinct but anatomically overlapping systems mediate the two effects. Thus while optogenetic stimulation provides a more selective tool for characterizing the mechanisms of stimulation-induced feeding and reward, it does not yet resolve the question of common or independent substrates.

Electrical Stimulation of the Ventral Tegmental Area Induces Reanimation from General Anesthesia

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Solt, Ken; Van Dort, Christa J.; Chemali, Jessica J.; Taylor, Norman E.; Kenny, Jonathan D.; Brown, Emery N.

2014-01-01

BACKGROUND Methylphenidate or a D1 dopamine receptor agonist induce reanimation (active emergence) from general anesthesia. We tested whether electrical stimulation of dopaminergic nuclei also induces reanimation from general anesthesia. METHODS In adult rats, a bipolar insulated stainless steel electrode was placed in the ventral tegmental area (VTA, n = 5) or substantia nigra (SN, n = 5). After a minimum 7-day recovery period, the isoflurane dose sufficient to maintain loss of righting was established. Electrical stimulation was initiated and increased in intensity every 3 min to a maximum of 120μA. If stimulation restored the righting reflex, an additional experiment was performed at least 3 days later during continuous propofol anesthesia. Histological analysis was conducted to identify the location of the electrode tip. In separate experiments, stimulation was performed in the prone position during general anesthesia with isoflurane or propofol, and the electroencephalogram was recorded. RESULTS To maintain loss of righting, the dose of isoflurane was 0.9% ± 0.1 vol%, and the target plasma dose of propofol was 4.4 μg/ml ± 1.1 μg/ml (mean ± SD). In all rats with VTA electrodes, electrical stimulation induced a graded arousal response including righting that increased with current intensity. VTA stimulation induced a shift in electroencephalogram peak power from δ (anesthesia with isoflurane or propofol. These results are consistent with the hypothesis that dopamine release by VTA, but not SN, neurons induces reanimation from general anesthesia. PMID:24398816

Organization of GABAergic synaptic circuits in the rat ventral tegmental area.

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Ciccarelli, Alessandro; Calza, Arianna; Panzanelli, Patrizia; Concas, Alessandra; Giustetto, Maurizio; Sassoè-Pognetto, Marco

2012-01-01

The ventral tegmental area (VTA) is widely implicated in drug addiction and other psychiatric disorders. This brain region is densely populated by dopaminergic (DA) neurons and also contains a sparse population of γ-aminobutyric acid (GABA)ergic cells that regulate the activity of the principal neurons. Therefore, an in-depth knowledge of the organization of VTA GABAergic circuits and of the plasticity induced by drug consumption is essential for understanding the mechanisms by which drugs induce stable changes in brain reward circuits. Using immunohistochemistry, we provide a detailed description of the localization of major GABA(A) and GABA(B) receptor subunits in the rat VTA. We show that DA and GABAergic cells express both GABA(A) and GABA(B) receptors. However VTA neurons differ considerably in the expression of GABA(A) receptor subunits, as the α1 subunit is associated predominantly with non-DA cells, whereas the α3 subunit is present at low levels in both types of VTA neurons. Using an unbiased stereological method, we then demonstrate that α1-positive elements represent only a fraction of non-DA neurons and that the ratio of DA and non-DA cells is quite variable throughout the rostro-caudal extent of the VTA. Interestingly, DA and non-DA cells receive a similar density of perisomatic synapses, whereas axo-dendritic synapses are significantly more abundant in non-DA cells, indicating that local interneurons receive prominent GABAergic inhibition. These findings reveal a differential expression of GABA receptor subtypes in the two major categories of VTA neurons and provide an anatomical basis for interpreting the plasticity of inhibitory circuits induced by drug exposure.

Organization of GABAergic synaptic circuits in the rat ventral tegmental area.

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Alessandro Ciccarelli

Full Text Available The ventral tegmental area (VTA is widely implicated in drug addiction and other psychiatric disorders. This brain region is densely populated by dopaminergic (DA neurons and also contains a sparse population of γ-aminobutyric acid (GABAergic cells that regulate the activity of the principal neurons. Therefore, an in-depth knowledge of the organization of VTA GABAergic circuits and of the plasticity induced by drug consumption is essential for understanding the mechanisms by which drugs induce stable changes in brain reward circuits. Using immunohistochemistry, we provide a detailed description of the localization of major GABA(A and GABA(B receptor subunits in the rat VTA. We show that DA and GABAergic cells express both GABA(A and GABA(B receptors. However VTA neurons differ considerably in the expression of GABA(A receptor subunits, as the α1 subunit is associated predominantly with non-DA cells, whereas the α3 subunit is present at low levels in both types of VTA neurons. Using an unbiased stereological method, we then demonstrate that α1-positive elements represent only a fraction of non-DA neurons and that the ratio of DA and non-DA cells is quite variable throughout the rostro-caudal extent of the VTA. Interestingly, DA and non-DA cells receive a similar density of perisomatic synapses, whereas axo-dendritic synapses are significantly more abundant in non-DA cells, indicating that local interneurons receive prominent GABAergic inhibition. These findings reveal a differential expression of GABA receptor subtypes in the two major categories of VTA neurons and provide an anatomical basis for interpreting the plasticity of inhibitory circuits induced by drug exposure.

Concomitant release of ventral tegmental acetylcholine and accumbal dopamine by ghrelin in rats.

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Elisabet Jerlhag

Full Text Available Ghrelin, an orexigenic peptide, regulates energy balance specifically via hypothalamic circuits. Growing evidence suggest that ghrelin increases the incentive value of motivated behaviours via activation of the cholinergic-dopaminergic reward link. It encompasses the cholinergic afferent projection from the laterodorsal tegmental area (LDTg to the dopaminergic cells of the ventral tegmental area (VTA and the mesolimbic dopamine system projecting from the VTA to nucleus accumbens (N.Acc.. Ghrelin receptors (GHS-R1A are expressed in these reward nodes and ghrelin administration into the LDTg increases accumbal dopamine, an effect involving nicotinic acetylcholine receptors in the VTA. The present series of experiments were undertaken directly to test this hypothesis. Here we show that ghrelin, administered peripherally or locally into the LDTg concomitantly increases ventral tegmental acetylcholine as well as accumbal dopamine release. A GHS-R1A antagonist blocks this synchronous neurotransmitter release induced by peripheral ghrelin. In addition, local perfusion of the unselective nicotinic antagonist mecamylamine into the VTA blocks the ability of ghrelin (administered into the LDTg to increase N.Acc.-dopamine, but not VTA-acetylcholine. Collectively our data indicate that ghrelin activates the LDTg causing a release of acetylcholine in the VTA, which in turn activates local nicotinic acetylcholine receptors causing a release of accumbal dopamine. Given that a dysfunction in the cholinergic-dopaminergic reward system is involved in addictive behaviours, including compulsive overeating and alcohol use disorder, and that hyperghrelinemia is associated with such addictive behaviours, ghrelin-responsive circuits may serve as a novel pharmacological target for treatment of alcohol use disorder as well as binge eating.

Functional connectivity of the ventral tegmental area and avolition in subjects with schizophrenia: a resting state functional MRI study.

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Giordano, Giulia Maria; Stanziano, Mario; Papa, Michele; Mucci, Armida; Prinster, Anna; Soricelli, Andrea; Galderisi, Silvana

2018-04-10

Avolition, a deficit in goal-directed behavior, is a key aspect of negative symptoms. It is highly prevalent in schizophrenia and is associated to poor functional outcome and to measures of real life motivation, indicating that central to the concept is the lack of interest and motivation. In this study we tested the hypothesis that avolition is related to altered connectivity within dopaminergic cortico-striatal circuits involved in motivation processes. Since dopamine input to these circuits derives mostly from the ventro-tegmental area (VTA), we investigated the relationships between the resting-state functional connectivity (RS-FC) of the VTA and avolition in twenty-six subjects with schizophrenia (SCZ), treated with second-generation antipsychotics only, compared to twenty-two healthy controls (HC). SCZ, in comparison to HC, showed significantly reduced RS-FC of the VTA with bilateral ventro-lateral prefrontal cortex (VLPFC), bilateral insular cortex (IC) and right (R) lateral occipital complex (LOC) and increased RS-FC of the VTA with bilateral dorso-lateral prefrontal cortex (DLPFC). Significant negative correlations were found between avolition and RS-FC of the VTA with the bilateral IC, R VLPFC and R LOC. According to our findings, avolition is linked to a disconnectivity of the VTA from several key cortical regions involved in the integration of value information with action selection. These findings are in line with translational animal models of "auto-activation apathy". Copyright © 2018 Elsevier B.V. and ECNP. All rights reserved.

Evaluation of GABA Receptors of Ventral Tegmental Area in Cardiovascular Responses in Rat

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Minoo Rasoulpanah

2015-07-01

Full Text Available Background: The ventral tegmental area (VTA is well known for its role in cardiovascular control. It is demonstrated that about 20-30% of the VTA neurons are GABAergic though their role in cardiovascular control is not yet understood. This study is carried out to find the effects of GABA A and GABA B receptors on cardiovascular response of the VTA. Methods: Experiments were performed on urethane anesthetized male Wistar rats. Drugs were microinjected unilaterally into the VTA. The average changes in mean arterial pressure (MAP and heart rate (HR were compared between the case and the control groups using t test and with the pre-injection values using paired t test. Results: Microinjection of muscimol, a GABAA agonist (500, 1500 and 2500 pmol/100nl into the VTA had no significant effect on MAP and HR compared with the saline group and pre-injection values. Injection of bicuculline methiodide (BMI, 100 and 200 pmol/100 nl, a GABAA antagonist, caused a significant increase in the MAP (11.1±1.95mmHg, P<0.5 and a decrease in HR (-32.07±10.2, P<0.01. Microinjection of baclofen a GABAB receptor agonist (500 or 1000 pmole/100 nl and phaclofen a GABAB receptor antagonist (500 or 1000 pmole/100 nl had no significant effects on MAP and HR. Conclusion: For the first time it was demonstrated that GABA system of the VTA inhibits the cardiovascular system through the activation of GABAA but not the GABAB receptors.

Abnormal ventral tegmental area-anterior cingulate cortex connectivity in Parkinson's disease with depression.

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Wei, Luqing; Hu, Xiao; Yuan, Yonggui; Liu, Weiguo; Chen, Hong

2018-07-16

Neuropathology suggests that Parkinson's disease (PD) with depression may involve a progressive degeneration of the nigrostriatal and mesocorticolimbic dopaminergic systems. Previous positron emission tomography (PET) and single-photon emission computed tomography (SPECT) studies have shown that dopamine changes in individual brain regions constituting the nigrostriatal and mesocorticolimbic circuits are associated with depression in PD. However, few studies have been conducted on the circuit-level alterations in this disease. The present study used resting-state fMRI and seed-based functional connectivity of putative dopaminergic midbrain regions (i.e., substantia nigra (SN) and ventral tegmental area (VTA)) to investigate the circuit-related abnormalities in PD with depression. The results showed that depressed PD (DPD) patients relative to healthy controls (HC) and non-depressed PD (NDPD) patients had increased functional connectivity between VTA and anterior cingulate cortex (ACC), demonstrating that dysfunctional mesocorticolimbic dopaminergic neurotransmission may be associated with depression in PD. Compared with HC, DPD and NDPD patients showed increased functional connectivity from SN to sensorimotor cortex, validating that alterations in the nigrostriatal circuitry could be responsible for cardinal motor features in PD. In addition, aberrant connectivity between VTA and ACC was correlated with the severity of depression in PD patients, further supporting that abnormal mesocorticolimbic system may account for depressive symptoms in PD. These results have provided potential circuit-level biomarkers of depression in PD, and suggested that resting state functional connectivity of midbrain dopaminergic nuclei may be useful for understanding the underlying pathology in PD with depression. Copyright © 2018 Elsevier B.V. All rights reserved.

Ventral tegmental area orexin 1 receptors promote palatable food intake and oppose postingestive negative feedback.

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Terrill, Sarah J; Hyde, Kellie M; Kay, Kristen E; Greene, Hayden E; Maske, Calyn B; Knierim, Amanda E; Davis, Jon F; Williams, Diana L

2016-09-01

Hypothalamic orexin neurons project to numerous brain areas, including the ventral tegmental area (VTA), which is involved in motivation and food-seeking behavior. Here we address how exogenously administered orexin-A and endogenous orexin 1 receptor (OX1R) activation in the VTA affects feeding behavior. We hypothesized that orexin-A and OX1R antagonist SB334867 delivered to the VTA, at doses that were subthreshold for effect when injected into the ventricle, would affect intake of palatable foods in multiple test situations. We first used a hedonic feeding model in which satiated rats selectively consume a high-fat diet (HFD). Intra-VTA orexin-A stimulated additional consumption of chow and increased HFD intake in this model. In ad libitum-fed rats given daily 30-min test sessions, intra-VTA orexin-A also increased intake of HFD and 0.1 M sucrose. Further analysis of licking patterns revealed that that VTA orexin-A increased meal size and licking burst size only toward the end of the meal. Consistent with this finding, a subthreshold dose of VTA orexin-A prevented intake suppression induced by gastrointestinal nutrient infusion. Surprisingly, intra-VTA orexin-A had no effect on operant responding for sucrose pellets on a progressive ratio schedule of reinforcement. A role for endogenous VTA OX1R stimulation is supported by our finding that bilateral VTA injection of the selective OX1R antagonist SB334867 suppressed 0.1 M sucrose intake. Together, our data suggest that OX1R activity in the VTA facilitates food intake, potentially by counteracting postingestive negative feedback that would normally suppress feeding later in a meal. Copyright © 2016 the American Physiological Society.

Alterations in food intake elicited by GABA and opioid agonists and antagonists administered into the ventral tegmental area region of rats.

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Echo, Joyce A; Lamonte, Nicole; Ackerman, Tsippa F; Bodnar, Richard J

2002-05-01

Food intake is significantly increased following administration of mu-selective opioid agonists into the ventral tegmental area (VTA) region acting through multiple local opioid receptor subtypes. Since GABA receptor agonists in the VTA region are capable of eliciting feeding, the present study investigated whether feeding elicited by the mu-selective opioid agonist [D-Ala(2), NMe(4), Gly-ol(5)]-enkephalin (DAMGO) in the VTA region was altered by pretreatment into the same site with equimolar doses of either GABA(A) (bicuculline) or GABA(B) (saclofen) antagonists, and further, whether pretreatment with either general opioid or selective GABA receptor antagonists decreased feeding elicited by GABA(A) (muscimol) or GABA(B) (baclofen) agonists in the VTA region. DAMGO-induced feeding in the VTA region was dose-dependently decreased following pretreatment with either GABA(A) or GABA(B) antagonists in the absence of significant alterations in food intake by the antagonists per se. However, the presence of short-lived seizures following bicuculline in the VTA region suggests that this ingestive effect was caused by nonspecific actions. In contrast, GABA(B) receptors are involved in the full expression of mu-opioid agonist-induced feeding in this region since saclofen failed to elicit either seizure activity or a conditioned taste aversion. Pretreatment with naltrexone in the VTA region reduced intake elicited by baclofen, but not muscimol. Finally, baclofen-induced feeding was significantly reduced by saclofen, but not bicuculline, pretreatment in the VTA region. Therefore, possible coregulation between GABA(B) and opioid receptors in the VTA region, as suggested by immunocytochemical evidence, is supported by these behavioral effects upon ingestion.

Oleic Acid in the Ventral Tegmental Area Inhibits Feeding, Food Reward, and Dopamine Tone.

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Hryhorczuk, Cecile; Sheng, Zhenyu; Décarie-Spain, Léa; Giguère, Nicolas; Ducrot, Charles; Trudeau, Louis-Éric; Routh, Vanessa H; Alquier, Thierry; Fulton, Stephanie

2018-02-01

Long-chain fatty acids (FAs) act centrally to decrease food intake and hepatic glucose production and alter hypothalamic neuronal activity in a manner that depends on FA type and cellular transport proteins. However, it is not known whether FAs are sensed by ventral tegmental area (VTA) dopamine (DA) neurons to control food-motivated behavior and DA neurotransmission. We investigated the impact of the monounsaturated FA oleate in the VTA on feeding, locomotion, food reward, and DA neuronal activity and DA neuron expression of FA-handling proteins and FA uptake. A single intra-VTA injection of oleate, but not of the saturated FA palmitate, decreased food intake and increased locomotor activity. Furthermore, intra-VTA oleate blunted the rewarding effects of high-fat/sugar food in an operant task and inhibited DA neuronal firing. Using sorted DA neuron preparations from TH-eGFP mice we found that DA neurons express FA transporter and binding proteins, and are capable of intracellular transport of long-chain FA. Finally, we demonstrate that a transporter blocker attenuates FA uptake into DA neurons and blocks the effects of intra-VTA oleate to decrease food-seeking and DA neuronal activity. Together, these results suggest that DA neurons detect FA and that oleate has actions in the VTA to suppress DA neuronal activity and food seeking following cellular incorporation. These findings highlight the capacity of DA neurons to act as metabolic sensors by responding not only to hormones but also to FA nutrient signals to modulate food-directed behavior.

Involvement of serotonin in the ventral tegmental area in thermoregulation of freely moving rats.

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Ishiwata, Takayuki; Hasegawa, Hiroshi; Greenwood, Benjamin N

2017-07-13

We have recently reported that the serotonin (5-HT) projections from the midbrain's raphe nuclei that contains 5-HT cell bodies may play a role both in heat production and in heat loss. The purpose of the present study was to clarify the involvement of 5-HT in the ventral tegmental area (VTA), where 5-HT is suggested to participate in thermoregulation, using the combined methods of telemetry, microdialysis, and high performance liquid chromatography, with a special emphasis on regulation of the body temperature (T b ) in freely moving rats. First, we measured changes in T b , tail skin temperature (T tail ; an index of heat loss), heart rate (HR; an index of heat production), locomotor activity (Act), and levels of extracellular monoamines in the VTA during cold (5°C) or heat (35°C) exposure. Subsequently, we perfused citalopram (5-HT re-uptake inhibitor) into the VTA and measured the thermoregulatory parameters and monoamines release. Although T b , T tail , and HR changed during both exposures, significant changes in extracellular level of 5-HT (138.7±12.7% baseline, p<0.01), but not dopamine (DA) or noradrenaline (NA) were noted in the VTA only during heat exposure. In addition, perfusion of citalopram into the VTA increased extracellular 5-HT levels (221.0±52.2% baseline, p<0.01), but not DA or NA, while T b decreased from 37.4±0.1°C to 36.8±0.2°C (p<0.001),T tail increased from 26.3±0.4°C to 28.4±0.4°C (p<0.001), and HR and Act remained unchanged. Our results suggest that the VTA is a key area for thermoregulation, and 5-HT, but not DA or NA, modulates the heat loss system through action in the VTA. Copyright © 2017 Elsevier B.V. All rights reserved.

Reduced activation in the ventral striatum during probabilistic decision-making in patients in an at-risk mental state

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Rausch, Franziska; Mier, Daniela; Eifler, Sarah; Fenske, Sabrina; Schirmbeck, Frederike; Englisch, Susanne; Schilling, Claudia; Meyer-Lindenberg, Andreas; Kirsch, Peter; Zink, Mathias

2015-01-01

Patients with schizophrenia display metacognitive impairments, such as hasty decision-making during probabilistic reasoning - the "jumping to conclusion" bias (JTC). Our recent fMRI study revealed reduced activations in the right ventral striatum (VS) and the ventral tegmental area (VTA) to be

Effects of unilatral- and bilateral inhibition of rostral ventral tegmental area and central nucleus of amygdala on morphine-induced place conditioning in male Wistar rat.

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Mohammadian, Zahra; Sahraei, Hedayat; Meftahi, Gholam Hossein; Ali-Beik, Hengameh

2017-03-01

The rostral ventral tegmental area (VTAR) and central nucleus of amygdala (CeA) are considered the main regions for induction of psychological dependence on abused drugs, such as morphine. The main aim of this study was to investigate the transient inhibition of each right and left side as well as both sides of the VTAR and the CeA by lidocaine (2%) on morphine reward properties using the conditioned place preference (CPP) method. Male Wistar rats (250±20 g) 7 days after recovery from surgery and cannulation were conditioned to morphine (7.5 mg/kg) in CPP apparatus. Five minutes before morphine injection in conditioning phase, lidocaine was administered either uni- or bilaterally into the VTAR (0.25 μL/site) or CeA (0.5 μL/site). The results revealed that lidocaine administration into the left side, but not the right side of the VTAR and the CeA reduced morphine CPP significantly. The reduction was potentiated when lidocaine was injected into both sides of the VTAR and the CeA. The number of compartment crossings was reduced when lidocaine was injected into both sides of the VTAR and the CeA as well as the left side. Rearing was reduced when lidocaine was injected into the right, but not the left side of the VTAR. Sniffing and rearing increased when animals received lidocaine in the right side and reduced in the group that received lidocaine in the left side of the CeA. It was concluded that the right and the left side of VTAR and the CeA play different roles in morphine-induced activity and reward. © 2016 John Wiley & Sons Australia, Ltd.

Neurotrophins in the ventral tegmental area: Role in social stress, mood disorders and drug abuse.

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Nikulina, E M; Johnston, C E; Wang, J; Hammer, R P

2014-12-12

This review discusses the impact of neurotrophins and other trophic factors, including fibroblast growth factor and glial cell line-derived neurotrophic factor, on mood disorders, weight regulation and drug abuse, with an emphasis on stress- and drug-induced changes in the ventral tegmental area (VTA). Neurotrophins, comprising nerve growth factor, brain-derived neurotrophic factor (BDNF), and neurotrophins 3 and 4/5 play important roles in neuronal plasticity and the development of different psychopathologies. In the VTA, most research has focused on the role of BDNF, because other neurotrophins are not found there in significant quantities. BDNF originating in the VTA provides trophic support to dopamine neurons. The diverse intracellular signaling pathways activated by BDNF may underlie precise physiological functions specific to the VTA. In general, VTA BDNF expression increases after psychostimulant exposures, and enhanced BDNF level in the VTA facilitates psychostimulant effects. The impact of VTA BDNF on the behavioral effects of psychostimulants relies primarily on its action within the mesocorticolimbic circuit. In the case of opiates, VTA BDNF expression and effects seem to be dependent on whether an animal is drug-naïve or has a history of drug use, only the latter of which is related to dopamine mechanisms. Social defeat stress that is continuous in mice or intermittent in rats increases VTA BDNF expression, and is associated with depressive and social avoidance behaviors. Intermittent social defeat stress induces persistent VTA BDNF expression that triggers psychostimulant cross-sensitization. Understanding the cellular and molecular substrates of neurotrophin effects may lead to novel therapeutic approaches for the prevention and treatment of substance use and mood disorders. Copyright © 2014 IBRO. Published by Elsevier Ltd. All rights reserved.

Local field potentials in the ventral tegmental area during cocaine-induced locomotor activation: Measurements in freely moving rats.

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Harris Bozer, Amber L; Li, Ai-Ling; Sibi, Jiny E; Bobzean, Samara A M; Peng, Yuan B; Perrotti, Linda I

2016-03-01

The ventral tegmental area (VTA) has been established as a critical nucleus for processing behavioral changes that occur during psychostimulant use. Although it is known that cocaine induced locomotor activity is initiated in the VTA, not much is known about the electrical activity in real time. The use of our custom-designed wireless module for recording local field potential (LFP) activity provides an opportunity to confirm and identify changes in neuronal activity within the VTA of freely moving rats. The purpose of this study was to investigate the changes in VTA LFP activity in real time that underlie cocaine induced changes in locomotor behavior. Recording electrodes were implanted in the VTA of rats. Locomotor behavior and LFP activity were simultaneously recorded at baseline, and after saline and cocaine injections. Results indicate that cocaine treatment caused increases in both locomotor behavior and LFP activity in the VTA. Specifically, LFP activity was highest during the first 30 min following the cocaine injection and was most robust in Delta and Theta frequency bands; indicating the role of low frequency VTA activity in the initiation of acute stimulant-induced locomotor behavior. Our results suggest that LFP recording in freely moving animals can be used in the future to provide valuable information pertaining to drug induced changes in neural activity. Copyright © 2016 Elsevier Inc. All rights reserved.

Lesions of cholinergic pedunculopontine tegmental nucleus neurons fail to affect cocaine or heroin self-administration or conditioned place preference in rats.

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Stephan Steidl

Full Text Available Cholinergic input to the ventral tegmental area (VTA is known to contribute to reward. Although it is known that the pedunculopontine tegmental nucleus (PPTg provides an important source of excitatory input to the dopamine system, the specific role of PPTg cholinergic input to the VTA in cocaine reward has not been previously determined. We used a diphtheria toxin conjugated to urotensin-II (Dtx::UII, the endogenous ligand for urotensin-II receptors expressed by PPTg cholinergic but not glutamatergic or GABAergic cells, to lesion cholinergic PPTg neurons. Dtx::UII toxin infusion resulted in the loss of 95.78 (±0.65% of PPTg cholinergic cells but did not significantly alter either cocaine or heroin self-administration or the development of cocaine or heroin conditioned place preferences. Thus, cholinergic cells originating in PPTg do not appear to be critical for the rewarding effects of cocaine or of heroin.

Dynamic, nonlinear feedback regulation of slow pacemaking by A-type potassium current in ventral tegmental area neurons.

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Khaliq, Zayd M; Bean, Bruce P

2008-10-22

We analyzed ionic currents that regulate pacemaking in dopaminergic neurons of the mouse ventral tegmental area by comparing voltage trajectories during spontaneous firing with ramp-evoked currents in voltage clamp. Most recordings were made in brain slice, with key experiments repeated using acutely dissociated neurons, which gave identical results. During spontaneous firing, net ionic current flowing between spikes was calculated from the time derivative of voltage multiplied by cell capacitance, signal-averaged over many firing cycles to enhance resolution. Net inward interspike current had a distinctive nonmonotonic shape, reaching a minimum (generally current that peaked near -55 mV. This current was undetectable with 5 mV/s ramps and increased steeply with depolarization rate over the range (10-50 mV/s) typical of natural pacemaking. Ramp-evoked subthreshold current was resistant to alpha-dendrotoxin, paxilline, apamin, and tetraethylammonium but sensitive to 4-aminopyridine and 0.5 mM Ba2+, consistent with A-type potassium current (I(A)). Same-cell comparison of currents elicited by various ramp speeds with natural spontaneous depolarization showed how the steep dependence of I(A) on depolarization rate results in small net inward currents during pacemaking. These results reveal a mechanism in which subthreshold I(A) is near zero at steady state, but is engaged at depolarization rates >10 mV/s to act as a powerful, supralinear feedback element. This feedback mechanism explains how net ionic current can be constrained to <1-2 pA but reliably inward, thus enabling slow, regular firing.

Acute Cocaine Exposure elicits rises in calcium in Arousal Related Laterodorsal Tegmental Neurons

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Lambert, Mads; Ipsen, Theis; Kohlmeier, Kristi Anne

2017-01-01

Cocaine has strong reinforcing properties, which underlie its high addiction potential. Reinforcement of use of addictive drugs is associated with rises in dopamine (DA) in mesoaccumbal circuitry. Excitatory afferent input to mesoaccumbal circuitry sources from the laterodorsal tegmental nucleus...... (LDT). Chronic, systemic cocaine exposure has been shown to have cellular effects on LDT cells, but acute actions of local application have never been demonstrated. Using calcium imaging, we show that acute application of cocaine to mouse brain slices induces calcium spiking in cells of the LDT....... Spiking was attenuated by tetrodotoxin (TTX) and low calcium solutions, and abolished by prior exhaustion of intracellular calcium stores. Further, DA receptor antagonists reduced these transients, whereas DA induced rises with similar spiking kinetics. Amphetamine, which also results in elevated levels...

GABAA receptor drugs and neuronal plasticity in reward and aversion: focus on the ventral tegmental area

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Elena eVashchinkina

2014-11-01

Full Text Available GABAA receptors are the main fast inhibitory neurotransmitter receptors in the mammalian brain, and targets for many clinically important drugs widely used in the treatment of anxiety disorders, insomnia and in anesthesia. Nonetheless, there are significant risks associated with the long-term use of these drugs particularly related to development of tolerance and addiction. Addictive mechanisms of GABAA receptor drugs are poorly known, but recent findings suggest that those drugs may induce aberrant neuroadaptations in the brain reward circuitry. Recently, benzodiazepines, acting on synaptic GABAA receptors, and modulators of extrasynaptic GABAA receptors (THIP and neurosteroids have been found to induce plasticity in the ventral tegmental area (VTA dopamine neurons and their main target projections. Furthermore, depending whether synaptic or extrasynaptic GABAA receptor populations are activated, the behavioral outcome of repeated administration seems to correlate with rewarding or aversive behavioral responses, respectively. The VTA dopamine neurons project to forebrain centers such as the nucleus accumbens and medial prefrontal cortex, and receive afferent projections from these brain regions and especially from the extended amygdala and lateral habenula, forming the major part of the reward and aversion circuitry. Both synaptic and extrasynaptic GABAA drugs inhibit the VTA GABAergic interneurons, thus activating the VTA DA neurons by disinhibition and this way inducing glutamatergic synaptic plasticity. However, the GABAA drugs failed to alter synaptic spine numbers as studied from Golgi-Cox-stained VTA dendrites. Since the GABAergic drugs are known to depress the brain metabolism and gene expression, their likely way of inducing neuroplasticity in mature neurons is by disinhibiting the principal neurons, which remains to be rigorously tested for a number of clinically important anxiolytics, sedatives and anesthetics in different parts of

Assessment of cytochrome C oxidase dysfunction in the substantia nigra/ventral tegmental area in schizophrenia.

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Matthew W Rice

Full Text Available Perturbations in metabolism are a well-documented but complex facet of schizophrenia pathology. Optimal cellular performance requires the proper functioning of the electron transport chain, which is constituted by four enzymes located within the inner membrane of mitochondria. These enzymes create a proton gradient that is used to power the enzyme ATP synthase, producing ATP, which is crucial for the maintenance of cellular functioning. Anomalies in a single enzyme of the electron transport chain are sufficient to cause disruption of cellular metabolism. The last of these complexes is the cytochrome c oxidase (COX enzyme, which is composed of thirteen different subunits. COX is a major site for oxidative phosphorylation, and anomalies in this enzyme are one of the most frequent causes of mitochondrial pathology. The objective of the present report was to assess if metabolic anomalies linked to COX dysfunction may contribute to substantia nigra/ventral tegmental area (SN/VTA pathology in schizophrenia. We tested COX activity in postmortem SN/VTA from schizophrenia and non-psychiatric controls. We also tested the protein expression of key subunits for the assembly and activity of the enzyme, and the effect of antipsychotic medication on subunit expression. COX activity was not significantly different between schizophrenia and non-psychiatric controls. However, we found significant decreases in the expression of subunits II and IV-I of COX in schizophrenia. Interestingly, these decreases were observed in samples containing the entire rostro-caudal extent of the SN/VTA, while no significant differences were observed for samples containing only mid-caudal regions of the SN/VTA. Finally, rats chronically treated with antipsychotic drugs did not show significant changes in COX subunit expression. These findings suggest that COX subunit expression may be compromised in specific sub-regions of the SN/VTA (i.e. rostral regions, which may lead to a faulty

Tyrosine hydroxylase in the ventral tegmental area of rams with high or low libido-A role for dopamine.

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Kramer, A C; Mirto, A J; Austin, K J; Roselli, C E; Alexander, B M

2017-12-01

Dopamine synthesis in the ventral tegmental area (VTA) is necessary for the reinforcement of sexual behavior. The objective of this study determined if sexual stimuli initiates reward, and whether reward is attenuated in sexually inactive rams. Sexually active rams were exposed to urine from estrous (n=4) or ovariectomized (n=3) ewes with inactive rams (n=3) exposed to urine from estrous ewes. Following exposure, rams were exsanguinated and brains perfused. Alternating sections of the VTA were stained for Fos related antigens (FRA), tyrosine hydroxylase, and dopamine beta-hydroxylase activity. Forebrain tissue, mid-sagittal ventral to the anterior corpus callosum, was stained for dopamine D 2 receptors. Concentrations of cortisol was determined prior to and following exposure. Exposure to ovariectomized-ewe urine in sexually active rams did not influence (P=0.6) FRA expression, but fewer (PSexually inactive rams had fewer (Psexually active rams following exposure to estrous ewe urine. VTA neurons staining positive for dopamine beta-hydroxylase did not differ by sexual activity (P=0.44) or urine exposure (P=0.07). Exposure to stimulus did not influence (P=0.46) numbers of forebrain neurons staining positive for dopamine D2 receptors in sexually active rams, but fewer (P=0.04) neurons stain positive in inactive rams. Serum concentrations of cortisol did not differ (P≥0.52) among rams prior to or following stimulus. In conclusion sexual inactivity is unlikely due to stress, but may be partially a result of decreased tyrosine hydroxylase and/or the response to dopamine. Copyright © 2017 Elsevier B.V. All rights reserved.

Tribute to: Self-administered nicotine activates the mesolimbic dopamine system through the ventral tegmental area [William Corrigall, Kathleen Coen and Laurel Adamson, Brain Res. 653 (1994) 278-284].

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Leri, Francesco; Vaccarino, Franco J

2016-08-15

In this paper, Dr. Corrigall and collaborators described elegant experiments designed to elucidate the neurobiology of nicotine reinforcement. The nicotinic receptor antagonist dihydro-β-erythroidine (DHβE) was infused in the ventral tegmental area (VTA) or nucleus accumbens (NAC) of rats trained to self-administer nicotine intravenously. Additionally, DHβE was infused in the VTA of rats trained to self-administer food or cocaine, and nicotine self-administration was assessed in rats with lesions to the peduculopontine tegmental nucleus (PPT). A number of key themes emerged from this fundamental study that remain relevant today. The primary finding was that infusions of DHβE in the VTA, but not in the NAC, lowered nicotine self-administration, suggesting that nicotinic receptors in VTA are involved in the reinforcing action of nicotine. This conclusion has been confirmed by subsequent findings, and the nature of the nicotinic receptors has also been elucidated. The authors also reported that DHβE in the VTA had no effect on food or cocaine self-administration, and that lesions to the PPT did not alter nicotine self-administration. Since this initial investigation, the question of whether nicotinic receptors in the VTA are necessary for the reinforcing action of other stimuli, and by which mechanisms, has been extensively explored. Similarly, many groups have further investigated the role of mesopontine cholinergic nuclei in reinforcement. This paper not only contributed in important ways to our understanding of the neurochemical basis of nicotine reinforcement, but was also a key catalyst that gave rise to several research themes central to the neuropharmacology of substance abuse. This article is part of a Special Issue entitled SI:50th Anniversary Issue. Copyright © 2016 Elsevier B.V. All rights reserved.

microRNA and mRNA profiles in ventral tegmental area relevant to stress-induced depression and resilience.

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Sun, Xiaoyan; Song, Zhenhua; Si, Yawei; Wang, Jin-Hui

2018-06-01

Chronic stress with lack of reward presumably may impair brain reward circuit, leading to major depressive disorder (MDD). Most individuals experiencing chronic stress do not suffer from MDD, i.e., resilience, implying the presence of endogenous anti-depression in the brain. Molecular mechanisms underlying stress-induced depression versus resilience were investigated. Mice were treated by chronic unpredictable mild stress (CUMS) for four weeks. Their mood state was assessed by behavioral tasks, such as sucrose preference, Y-maze and forced swimming testes. To reveal comprehensive molecular profiles of major depression versus resilience, mRNA and microRNA profiles were analyzed by high-throughput sequencing in the ventral tegmental area (VTA) harvested from control, CUMS-susceptible and CUMS-resilience mice. In data analyses of control versus CUMS-susceptible mice as well as control versus CUMS-resilience mice, 1.5 fold ratio in reads per kilo-base per million reads was set as the threshold to judge the involvement of mRNAs and microRNAs in the CUMS, depression or resilience. The downregulation of synaptic vesicle cycle, neurotrophin, GABAergic synapse and morphine addiction as well as the upregulation of transmitter release, calcium signal and cAMP-dependent response element binding are associated to CUMS-susceptibility. The downregulation of tyrosine metabolism and protein process in endoplasmic reticulum as well as the upregulation of amino acid biosynthesis, neuroactive ligand-receptor interaction and dopaminergic synapse are associated to CUMS-resilience. Therefore, the impairment of neurons and GABA/dopaminergic synapses in the VTA is associated with major depression. The upregulation of these entities is associated with resilience. Consistent results obtained from analyzing mRNAs and microRNAs as well as using different approaches strengthen our finding and conclusion. Copyright © 2018. Published by Elsevier Inc.

Contribution of ventral tegmental GABA receptors to cocaine self-administration in rats.

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Backes, E N; Hemby, S E

2008-03-01

Recent evidence has suggested that compounds affecting GABAergic transmission may provide useful pharmacological tools for the treatment of cocaine addiction. Using a rat model of self-administration, the present study examined the effects of GABA agonists and antagonists injected directly into the ventral tegmental area (VTA) on cocaine intake in rats trained to self-administer cocaine (0, 125, 250 and 500 microg/infusion) under an FR5 schedule of reinforcement. Separate groups of rats received bilateral intra-VTA injections of the GABA-A antagonist picrotoxin (34 ng/side, n = 7; 68 ng/side, n = 8), GABA-A agonist muscimol (14 ng/side, n = 8), GABA-B agonist baclofen (56 ng/side, n = 7; 100 ng/side, n = 6), picrotoxin (68 ng/side) co-injected with the GABA-B antagonist 2-hydroxysaclofen (100 ng/side, n = 7; 2 microg/side, n = 8) or artificial cerebrospinal fluid (aCSF, n = 6) to assess the effects of the various compounds on the cocaine self-administration dose-response curve. Both picrotoxin and baclofen reduced responding maintained by cocaine, whereas muscimol had no effect on responding. In contrast, neither picrotoxin (n = 6) nor baclofen (n = 8) affected responding maintained by food. Interestingly, 2-hydroxysaclofen effectively blocked the suppression of responding produced by picrotoxin, suggesting that both picrotoxin and baclofen exert their effects via activation of GABA-B receptors. Additionally, these effects appear to be specific to cocaine reinforcement, supporting current investigation of baclofen as a treatment for cocaine addiction.

Decreased functional connectivity between ventral tegmental area and nucleus accumbens in Internet gaming disorder: evidence from resting state functional magnetic resonance imaging.

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Zhang, Jin-Tao; Ma, Shan-Shan; Yip, Sarah W; Wang, Ling-Jiao; Chen, Chao; Yan, Chao-Gan; Liu, Lu; Liu, Ben; Deng, Lin-Yuan; Liu, Qin-Xue; Fang, Xiao-Yi

2015-11-18

Internet gaming disorder (IGD) has become an increasing mental health problem worldwide. Decreased resting-state functional connectivity (rsFC) between the ventral tegmental area (VTA) and the nucleus accumbens (NAcc) has been found in substance use and is thought to play an important role in the development of substance addiction. However, rsFC between the VTA and NAcc in a non-substance addiction, such as IGD, has not been assessed previously. The current study aimed to investigate: (1) if individuals with IGD exhibit alterations in VTA-NAcc functional connectivity; and (2) whether VTA-NAcc functional connectivity is associated with subjective Internet craving. Thirty-five male participants with IGD and 24 healthy control (HC) individuals participated in resting-state functional magnetic resonance imaging. Regions of interest (left NAcc, right NAcc and VTA) were selected based on the literature and were defined by placing spheres centered on Talairach Daemon coordinates. In comparison with HCs, individuals with IGD had significantly decreased rsFC between the VTA and right NAcc. Resting-state functional connectivity strength between the VTA and right NAcc was negatively correlated with self-reported subjective craving for the Internet. These results suggest possible neural functional similarities between individuals with IGD and individuals with substance addictions.

Effects of drugs of abuse on putative rostromedial tegmental neurons, inhibitory afferents to midbrain dopamine cells.

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Lecca, Salvatore; Melis, Miriam; Luchicchi, Antonio; Ennas, Maria Grazia; Castelli, Maria Paola; Muntoni, Anna Lisa; Pistis, Marco

2011-02-01

Recent findings have underlined the rostromedial tegmental nucleus (RMTg), a structure located caudally to the ventral tegmental area, as an important site involved in the mechanisms of aversion. RMTg contains γ-aminobutyric acid neurons responding to noxious stimuli, densely innervated by the lateral habenula and providing a major inhibitory projection to reward-encoding midbrain dopamine (DA) neurons. One of the key features of drug addiction is the perseverance of drug seeking in spite of negative and unpleasant consequences, likely mediated by response suppression within neural pathways mediating aversion. To investigate whether the RMTg has a function in the mechanisms of addicting drugs, we studied acute effects of morphine, cocaine, the cannabinoid agonist WIN55212-2 (WIN), and nicotine on putative RMTg neurons. We utilized single unit extracellular recordings in anesthetized rats and whole-cell patch-clamp recordings in brain slices to identify and characterize putative RMTg neurons and their responses to drugs of abuse. Morphine and WIN inhibited both firing rate in vivo and excitatory postsynaptic currents (EPSCs) evoked by stimulation of rostral afferents in vitro, whereas cocaine inhibited discharge activity without affecting EPSC amplitude. Conversely, nicotine robustly excited putative RMTg neurons and enhanced EPSCs, an effect mediated by α7-containing nicotinic acetylcholine receptors. Our results suggest that activity of RMTg neurons is profoundly influenced by drugs of abuse and, as important inhibitory afferents to midbrain DA neurons, they might take place in the complex interplay between the neural circuits mediating aversion and reward.

Different amounts of ejaculatory activity, a natural rewarding behavior, induce differential mu and delta opioid receptor internalization in the rat's ventral tegmental area.

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Garduño-Gutiérrez, René; León-Olea, Martha; Rodríguez-Manzo, Gabriela

2013-12-06

Opioid receptors internalize upon specific agonist stimulation. The in vivo significance of receptor internalization is not well established, partly due to the limited in vivo models used to study this phenomenon. Ejaculation promotes endogenous opioid release which activates opioid receptors at the brain, including the mesolimbic system and medial preoptic area. The objective of the present work was to analyze if there was a correlation between the degree of in vivo mu (MOR) and delta opioid receptor (DOR) internalization in the ventral tegmental area and the execution of different amounts of ejaculatory behavior of male rats. To this aim, we analyzed the brains of rats that ejaculated once or six successive times and of sexually exhausted rats with an established sexual inhibition, using immunofluorescence and confocal microscopy. Results showed that MOR and DOR internalization increased as a consequence of ejaculation. There was a relationship between the amount of sexual activity executed and the degree of internalization for MOR, but not for DOR. MOR internalization was larger in rats that ejaculated repeatedly than in animals ejaculating only once. Significant DOR internalization was found only in animals ejaculating once. Changes in MOR, DOR and beta arrestin2 detection, associated to sexual activity, were also found. It is suggested that copulation to satiety might be useful as a model system to study the biological significance of receptor internalization. © 2013 Published by Elsevier B.V.

Inhibition by sigma receptor ligand, MS-377, of N-methyl- D-aspartate-induced currents in dopamine neurons of the rat ventral tegmental area.

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Yamazaki, Yuu; Ishioka, Miwa; Matsubayashi, Hiroaki; Amano, Taku; Sasa, Masashi

2002-04-01

MS-377 [( R)-(+)-1-(4-chlorophenyl)-3-[4-(2-methoxyethyl) piperazin-1-yl]methyl-2-pyrrolidinone L-tartrate] is a novel anti-psychotic drug candidate with high affinity for sigma receptors but devoid of binding affinity for PCP binding site of NMDA receptor/ion channel complex. The effects of MS-377 on NMDA receptor and/or its ion channel complex were examined to elucidate the antipsychotic properties of MS-377. We examined the effect of MS-377 on NMDA ( N-methyl- D-aspartate)-induced current in acutely dissociated dopamine neurons of rat ventral tegmental area (VTA) using patch clamp whole cell recording. MS-377 applied in a bath inhibited the peak current evoked by NMDA applied via the U-tube method for 2 s in a concentration-dependent manner. Other sigma receptor ligands, BD-1063 (1-[2-(3,4-dichlorophenyl)ethyl]-4-methylpiperazine), NE-100 ( N, N-dipropyl-2-[4-methoxy-3-(2-phenylenoxy)-phenyl]-ethylamine monohydrochloride) and haloperidol also inhibited NMDA-induced current in a concentration-dependent manner. Interestingly, concomitant application of MS-377 with BD-1063, NE-100 or haloperidol at concentrations that had no effects on NMDA-induced current, potentiated the MS-377-induced inhibition. The results suggest that MS-377, as well as other sigma receptor ligands, indirectly acts on the sigma receptor to inhibit glutaminergic transmission mediated by NMDA receptor/ion channel complex in VTA dopamine neurons, thereby inhibiting dopamine release in target VTA areas.

Opposite modulation of brain stimulation reward by NMDA and AMPA receptors in the ventral tegmental area.

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Ducrot, Charles; Fortier, Emmanuel; Bouchard, Claude; Rompré, Pierre-Paul

2013-01-01

Previous studies have shown that blockade of ventral tegmental area (VTA) glutamate N-Methyl-D-Aspartate (NMDA) receptors induces reward, stimulates forward locomotion and enhances brain stimulation reward. Glutamate induces two types of excitatory response on VTA neurons, a fast and short lasting depolarization mediated by α-amino-3-hydroxy-5-methyl-4-isoxazole propionate (AMPA) receptors and a longer lasting depolarization mediated by NMDA receptors. A role for the two glutamate receptors in modulation of VTA neuronal activity is evidenced by the functional change in AMPA and NMDA synaptic responses that result from repeated exposure to reward. Since both receptors contribute to the action of glutamate on VTA neuronal activity, we studied the effects of VTA AMPA and NMDA receptor blockade on reward induced by electrical brain stimulation. Experiments were performed on rats trained to self-administer electrical pulses in the medial posterior mesencephalon. Reward thresholds were measured with the curve-shift paradigm before and for 2 h after bilateral VTA microinjections of the AMPA antagonist, NBQX (2,3,-Dioxo-6-nitro-1,2,3,4-tetrahydrobenzo(f)quinoxaline-7-sulfonamide, 0, 80, and 800 pmol/0.5 μl/side) and of a single dose (0.825 nmol/0.5 μl/side) of the NMDA antagonist, PPPA (2R,4S)-4-(3-Phosphonopropyl)-2-piperidinecarboxylic acid). NBQX produced a dose-dependent increase in reward threshold with no significant change in maximum rate of responding. Whereas PPPA injected at the same VTA sites produced a significant time dependent decrease in reward threshold and increase in maximum rate of responding. We found a negative correlation between the magnitude of the attenuation effect of NBQX and the enhancement effect of PPPA; moreover, NBQX and PPPA were most effective when injected, respectively, into the anterior and posterior VTA. These results suggest that glutamate acts on different receptor sub-types, most likely located on different VTA neurons, to

Activation of D2 autoreceptors alters cocaine-induced locomotion and slows down local field oscillations in the rat ventral tegmental area.

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Koulchitsky, Stanislav; Delairesse, Charlotte; Beeken, Thom; Monteforte, Alexandre; Dethier, Julie; Quertemont, Etienne; Findeisen, Rolf; Bullinger, Eric; Seutin, Vincent

2016-09-01

Psychoactive substances affecting the dopaminergic system induce locomotor activation and, in high doses, stereotypies. Network mechanisms underlying the shift from an active goal-directed behavior to a "seemingly purposeless" stereotypic locomotion remain unclear. In the present study we sought to determine the relationships between the behavioral effects of dopaminergic drugs and their effects on local field potentials (LFPs), which were telemetrically recorded within the ventral tegmental area (VTA) of freely moving rats. We used the D2/D3 agonist quinpirole in a low, autoreceptor-selective (0.1 mg/kg, i.p.) and in a high (0.5 mg/kg, i.p.) dose, and a moderate dose of cocaine (10 mg/kg, i.p.). In the control group, power spectrum analysis revealed a prominent peak of LFP power in the theta frequency range during active exploration. Cocaine alone stimulated locomotion, but had no significant effect on the peak of the LFP power. In contrast, co-administration of low dose quinpirole with cocaine markedly altered the pattern of locomotion, from goal-directed exploratory behavior to recurrent motion resembling locomotor stereotypy. This behavioral effect was accompanied by a shift of the dominant theta power toward a significantly lower (by ∼15%) frequency. High dose quinpirole also provoked an increased locomotor activity with signs of behavioral stereotypies, and also induced a shift of the dominant oscillation frequency toward the lower range. These results demonstrate a correlation between the LFP oscillation frequency within the VTA and a qualitative aspect of locomotor behavior, perhaps due to a variable level of coherence of this region with its input or output areas. Copyright © 2016 Elsevier Ltd. All rights reserved.

The Role of Ventral Tegmental Area Gamma-Aminobutyric Acid in Chronic Neuropathic Pain after Spinal Cord Injury in Rats.

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Ko, Moon Yi; Jang, Eun Young; Lee, June Yeon; Kim, Soo Phil; Whang, Sung Hun; Lee, Bong Hyo; Kim, Hee Young; Yang, Chae Ha; Cho, Hee Jung; Gwak, Young S

2018-04-20

Spinal cord injury (SCI) frequently results in chronic neuropathic pain (CNP). However, the understanding of brain neural circuits in CNP modulation is unclear. The present study examined the changes of ventral tegmental area (VTA) putative GABAergic and dopaminergic neuronal activity with CNP attenuation in rats. SCI was established by T10 clip compression injury (35 g, 1 min) in rats, and neuropathic pain behaviors, in vivo extracellular single-cell recording of putative VTA gamma-aminobutyric acid (GABA)/dopamine neurons, extracellular GABA level, glutamic acid decarboxylase (GAD), and vesicular GABA transporters (VGATs) were measured in the VTA, respectively. The results revealed that extracellular GABA level was significantly increased in the CNP group (50.5 ± 18.9 nM) compared to the sham control group (10.2 ± 1.7 nM). In addition, expression of GAD 65/67 , c-Fos, and VGAT exhibited significant increases in the SCI groups compared to the sham control group. With regard to neuropathic pain behaviors, spontaneous pain measured by ultrasound vocalizations (USVs) and evoked pain measured by paw withdrawal thresholds showed significant alteration, which was reversed by intravenous (i.v.) administration of morphine (0.5-5.0 mg/kg). With regard to in vivo electrophysiology, VTA putative GABAergic neuronal activity (13.6 ± 1.7 spikes/sec) and putative dopaminergic neuronal activity (2.4 ± 0.8 spikes/sec) were increased and decreased, respectively, in the SCI group compared to the sham control group. These neuronal activities were reversed by i.v. administration of morphine. The present study suggests that chronic increase of GABAergic neuronal activity suppresses dopaminergic neuronal activity in the VTA and is responsible for negative emotion and motivation for attenuation of SCI-induced CNP.

NMDA receptor glycine modulatory site in the ventral tegmental area regulates the acquisition, retrieval, and reconsolidation of cocaine reward memory.

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Zhou, Shuang-jiang; Xue, Li-fen; Wang, Xue-yi; Jiang, Wen-gao; Xue, Yan-xue; Liu, Jian-feng; He, Yin-yin; Luo, Yi-xiao; Lu, Lin

2012-05-01

Accumulating clinical and preclinical studies have shown that the memories of the rewarding effects of drugs and their paired cues may contribute to relapse and persistent cocaine use. Glutaminergic actions in the ventral tegmental area (VTA) have been shown to regulate the rewarding effect of drugs and conditioned responses to drug-associated cues, but the role of the VTA in the acquisition, retrieval, and reconsolidation of cocaine cues is not yet known. In the present study, we used 7-chlorothiokynurenic acid (7-CTKA), an N-methyl-D-aspartate (NMDA) receptor glycine modulatory site antagonist with no rewarding effects, to examine the role of the NMDA receptor glycine modulatory site in the acquisition, retrieval, and reconsolidation of cocaine-related reward memory using the conditioned place preference (CPP) paradigm. Separate groups of Sprague-Dawley rats were trained to acquire cocaine-induced CPP. Vehicle or 7-CTKA was microinjected into the VTA or substantia nigra (SN) (5 μg/μl) at different time points: 10 min before each CPP training session (acquisition), 10 min before the reactivation of CPP (retrieval), and immediately after the reactivation of CPP (reconsolidation). Cocaine-induced CPP was retested 24 h and 1 and 2 weeks after 7-CTKA administration. 7-CTKA microinjected into the VTA, but not SN, significantly impaired the acquisition, retrieval, and reconsolidation of cocaine-induced CPP without affecting cocaine-induced locomotion. Our findings suggest that the NMDA receptor glycine modulatory site in the VTA plays a major role in cocaine reward memory, and NMDA receptor glycine site antagonists may be potential pharmacotherapies for the management of relapse.

The anatomy of the human medial forebrain bundle: Ventral tegmental area connections to reward-associated subcortical and frontal lobe regions

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Volker Arnd Coenen

Full Text Available Introduction: Despite their importance in reward, motivation, and learning there is only sparse anatomical knowledge about the human medial forebrain bundle (MFB and the connectivity of the ventral tegmental area (VTA. A thorough anatomical and microstructural description of the reward related PFC/OFC regions and their connection to the VTA - the superolateral branch of the MFB (slMFB - is however mandatory to enable an interpretation of distinct therapeutic effects from different interventional treatment modalities in neuropsychiatric disorders (DBS, TMS etc.. This work aims at a normative description of the human MFB (and more detailed the slMFB anatomy with respect to distant prefrontal connections and microstructural features. Methods and material: Healthy subjects (n = 55; mean age ± SD, 40 ± 10 years; 32 females underwent high resolution anatomical magnetic resonance imaging including diffusion tensor imaging. Connectivity of the VTA and the resulting slMFB were investigated on the group level using a global tractography approach. The Desikan/Killiany parceling (8 segments of the prefrontal cortex was used to describe sub-segments of the MFB. A qualitative overlap with Brodmann areas was additionally described. Additionally, a pure visual analysis was performed comparing local and global tracking approaches for their ability to fully visualize the slMFB. Results: The MFB could be robustly described both in the present sample as well as in additional control analyses in data from the human connectome project. Most VTA- connections reached the superior frontal gyrus, the middel frontal gyrus and the lateral orbitofrontal region corresponding to Brodmann areas 10, 9, 8, 11, and 11m. The projections to these regions comprised 97% (right and 98% (left of the total relative fiber counts of the slMFB. Discussion: The anatomical description of the human MFB shows far reaching connectivity of VTA to reward-related subcortical and

CaV3.1 isoform of T-type calcium channels supports excitability of rat and mouse ventral tegmental area neurons.

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Tracy, Matthew E; Tesic, Vesna; Stamenic, Tamara Timic; Joksimovic, Srdjan M; Busquet, Nicolas; Jevtovic-Todorovic, Vesna; Todorovic, Slobodan M

2018-03-23

Recent data have implicated voltage-gated calcium channels in the regulation of the excitability of neurons within the mesolimbic reward system. While the attention of most research has centered on high voltage L-type calcium channel activity, the presence and role of the low voltage-gated T-type calcium channel (T-channels) has not been well explored. Hence, we investigated T-channel properties in the neurons of the ventral tegmental area (VTA) utilizing wild-type (WT) rats and mice, Ca V 3.1 knock-out (KO) mice, and TH-eGFP knock-in (KI) rats in acute horizontal brain slices of adolescent animals. In voltage-clamp experiments, we first assessed T-channel activity in WT rats with characteristic properties of voltage-dependent activation and inactivation, as well as characteristic crisscrossing patterns of macroscopic current kinetics. T-current kinetics were similar in WT mice and WT rats but T-currents were abolished in Ca V 3.1 KO mice. In ensuing current-clamp experiments, we observed the presence of hyperpolarization-induced rebound burst firing in a subset of neurons in WT rats, as well as dopaminergic and non-dopaminergic neurons in TH-eGFP KI rats. Following the application of a pan-selective T-channel blocker TTA-P2, rebound bursting was significantly inhibited in all tested cells. In a behavioral assessment, the acute locomotor increase induced by a MK-801 (Dizocilpine) injection in WT mice was abolished in Ca V 3.1 KO mice, suggesting a tangible role for 3.1 T-type channels in drug response. We conclude that pharmacological targeting of Ca V 3.1 isoform of T-channels may be a novel approach for the treatment of disorders of mesolimbic reward system. Copyright © 2018. Published by Elsevier Ltd.

The dorsal tegmental noradrenergic projection: an analysis of its role in maze learning.

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Roberts, D C; Price, M T; Fibiger, H C

1976-04-01

The hypothesis that the noradrenergic projection from the locus coeruleus (LC) to the cerebral cortex and hippocampus is an important neural substrate for learning was evaluated. Maze performance was studied in rats receiving either electrolytic lesions of LC or 6-hydroxydopamine (6-OHDA) lesions of the dorsal tegmental noradrenergic projection. The LC lesions did not disrupt the acquisition of a running response for food reinforcement in an L-shaped runway, even though hippocampal-cortical norepinephrine (NE) was reduced to 29%. Greater telencephalic NE depletions (to 6% of control levels) produced by 6-OHDA also failed to disrupt the acquisition of this behavior or to impair the acquisition of a food-reinforced position habit in a T-maze. Neither locomotor activity nor habituation to a novel environment was affected by the 6-OHDA lesions. Rats with such lesions were, however, found to be significantly more distractible than were controls during the performance of a previously trained response. The hypothesis that telencephalic NE is of fundamental importance in learning was not supported. The data suggest that this system may participate in attentional mechanisms.

Characterization of cognitive deficits in rats overexpressing human alpha-synuclein in the ventral tegmental area and medial septum using recombinant adeno-associated viral vectors.

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Hall, Hélène; Jewett, Michael; Landeck, Natalie; Nilsson, Nathalie; Schagerlöf, Ulrika; Leanza, Giampiero; Kirik, Deniz

2013-01-01

Intraneuronal inclusions containing alpha-synuclein (a-syn) constitute one of the pathological hallmarks of Parkinson's disease (PD) and are accompanied by severe neurodegeneration of A9 dopaminergic neurons located in the substantia nigra. Although to a lesser extent, A10 dopaminergic neurons are also affected. Neurodegeneration of other neuronal populations, such as the cholinergic, serotonergic and noradrenergic cell groups, has also been documented in PD patients. Studies in human post-mortem PD brains and in rodent models suggest that deficits in cholinergic and dopaminergic systems may be associated with the cognitive impairment seen in this disease. Here, we investigated the consequences of targeted overexpression of a-syn in the mesocorticolimbic dopaminergic and septohippocampal cholinergic pathways. Rats were injected with recombinant adeno-associated viral vectors encoding for either human wild-type a-syn or green fluorescent protein (GFP) in the ventral tegmental area and the medial septum/vertical limb of the diagonal band of Broca, two regions rich in dopaminergic and cholinergic neurons, respectively. Histopathological analysis showed widespread insoluble a-syn positive inclusions in all major projections areas of the targeted nuclei, including the hippocampus, neocortex, nucleus accumbens and anteromedial striatum. In addition, the rats overexpressing human a-syn displayed an abnormal locomotor response to apomorphine injection and exhibited spatial learning and memory deficits in the Morris water maze task, in the absence of obvious spontaneous locomotor impairment. As losses in dopaminergic and cholinergic immunoreactivity in both the GFP and a-syn expressing animals were mild-to-moderate and did not differ from each other, the behavioral impairments seen in the a-syn overexpressing animals appear to be determined by the long term persisting neuropathology in the surviving neurons rather than by neurodegeneration.

Solar Cels With Reduced Contact Areas

Science.gov (United States)

Daud, T.; Crotty, G. T.; Kachare, A. H.; Lewis, J. T.

1987-01-01

Efficiency of silicon solar cells increased about 20 percent using smaller metal-contact area on silicon at front and back of each cell. Reduction in contact area reduces surface recombination velocity under contact and thus reduces reverse saturation current and increases opencircuit voltage..

Sex-Dependent Effects of Stress on Immobility Behavior and VTA Dopamine Neuron Activity: Modulation by Ketamine.

Science.gov (United States)

Rincón-Cortés, Millie; Grace, Anthony A

2017-10-01

Stress constitutes a risk factor across several psychiatric disorders. Moreover, females are more susceptible to stress-related disorders, such as depression, than males. Although dopamine system underactivation is implicated in the pathophysiology of depression, little is known about the female dopamine system at baseline and post-stress. The effects of chronic mild stress were examined on ventral tegmental area dopamine neuron activity and forced swim test immobility by comparing male and female rats. The impact of a single dose of the rapid antidepressant ketamine (10 mg/kg, i.p.) on forced swim test immobility and ventral tegmental area function was then tested. Baseline ventral tegmental area dopamine activity was comparable in both sexes. At baseline, females exhibited roughly double the forced swim test immobility duration than males, which corresponded to ~50% decrease in ventral tegmental area dopamine population activity compared with similarly treated (i.e., post-forced swim test) males. Following chronic mild stress, there was greater immobility duration in both sexes and reduced ventral tegmental area dopamine neuron activity by approximately 50% in males and nearly 75% in females. Ketamine restored behavior and post-forced swim test ventral tegmental area dopamine activity for up to 7 days in females as well as in both male and female chronic mild stress-exposed rats. These data suggest increased female susceptibility to depression-like phenotypes (i.e., greater immobility, ventral tegmental area hypofunction) is associated with higher dopamine system sensitivity to both acute and repeated stress relative to males. Understanding the neural underpinnings of sex differences in stress vulnerability will provide insight into mechanisms of disease and optimizing therapeutic approaches in both sexes. © The Author 2017. Published by Oxford University Press on behalf of CINP.

Oxytocin receptors are expressed on dopamine and glutamate neurons in the mouse ventral tegmental area that project to nucleus accumbens and other mesolimbic targets.

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Peris, Joanna; MacFadyen, Kaley; Smith, Justin A; de Kloet, Annette D; Wang, Lei; Krause, Eric G

2017-04-01

The mesolimbic dopamine (DA) circuitry determines which behaviors are positively reinforcing and therefore should be encoded in the memory to become a part of the behavioral repertoire. Natural reinforcers, like food and sex, activate this pathway, thereby increasing the likelihood of further consummatory, social, and sexual behaviors. Oxytocin (OT) has been implicated in mediating natural reward and OT-synthesizing neurons project to the ventral tegmental area (VTA) and nucleus accumbens (NAc); however, direct neuroanatomical evidence of OT regulation of DA neurons within the VTA is sparse. To phenotype OT-receptor (OTR) expressing neurons originating within the VTA, we delivered Cre-inducible adeno-associated virus that drives the expression of fluorescent marker into the VTA of male mice that had Cre-recombinase driven by OTR gene expression. OTR-expressing VTA neurons project to NAc, prefrontal cortex, the extended amygdala, and other forebrain regions but less than 10% of these OTR-expressing neurons were identified as DA neurons (defined by tyrosine hydroxylase colocalization). Instead, almost 50% of OTR-expressing cells in the VTA were glutamate (GLU) neurons, as indicated by expression of mRNA for the vesicular GLU transporter (vGluT). About one-third of OTR-expressing VTA neurons did not colocalize with either DA or GLU phenotypic markers. Thus, OTR expression by VTA neurons implicates that OT regulation of reward circuitry is more complex than a direct action on DA neurotransmission. J. Comp. Neurol. 525:1094-1108, 2017. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

The GABAA Receptor α2 Subunit Activates a Neuronal TLR4 Signal in the Ventral Tegmental Area that Regulates Alcohol and Nicotine Abuse

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Irina Balan

2018-04-01

Full Text Available Alcoholism initiates with episodes of excessive alcohol drinking, known as binge drinking, which is one form of excessive drinking (NIAAA Newsletter, 2004 that is related to impulsivity and anxiety (Ducci et al., 2007; Edenberg et al., 2004 and is also predictive of smoking status. The predisposition of non-alcohol exposed subjects to initiate binge drinking is controlled by neuroimmune signaling that includes an innately activated neuronal Toll-like receptor 4 (TLR4 signal. This signal also regulates cognitive impulsivity, a heritable trait that defines drug abuse initiation. However, the mechanism of signal activation, its function in dopaminergic (TH+ neurons within the reward circuitry implicated in drug-seeking behavior [viz. the ventral tegmental area (VTA], and its contribution to nicotine co-abuse are still poorly understood. We report that the γ-aminobutyric acidA receptor (GABAAR α2 subunit activates the TLR4 signal in neurons, culminating in the activation (phosphorylation/nuclear translocation of cyclic AMP response element binding (CREB but not NF-kB transcription factors and the upregulation of corticotropin-releasing factor (CRF and tyrosine hydroxylase (TH. The signal is activated through α2/TLR4 interaction, as evidenced by co-immunoprecipitation, and it is present in the VTA from drug-untreated alcohol-preferring P rats. VTA infusion of neurotropic herpes simplex virus (HSV vectors for α2 (pHSVsiLA2 or TLR4 (pHSVsiTLR4 but not scrambled (pHSVsiNC siRNA inhibits signal activation and both binge alcohol drinking and nicotine sensitization, suggesting that the α2-activated TLR4 signal contributes to the regulation of both alcohol and nicotine abuse.

Endogenous Glucagon-like Peptide-1 Suppresses High-Fat Food Intake by Reducing Synaptic Drive onto Mesolimbic Dopamine Neurons

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Xue-Feng Wang

2015-08-01

Full Text Available Glucagon-like peptide-1 (GLP-1 and its analogs act as appetite suppressants and have been proven to be clinically efficacious in reducing body weight in obese individuals. Central GLP-1 is expressed in a small population of brainstem cells located in the nucleus tractus solitarius (NTS, which project to a wide range of brain areas. However, it remains unclear how endogenous GLP-1 released in the brain contributes to appetite regulation. Using chemogenetic tools, we discovered that central GLP-1 acts on the midbrain ventral tegmental area (VTA and suppresses high-fat food intake. We used integrated pathway tracing and synaptic physiology to further demonstrate that activation of GLP-1 receptors specifically reduces the excitatory synaptic strength of dopamine (DA neurons within the VTA that project to the nucleus accumbens (NAc medial shell. These data suggest that GLP-1 released from NTS neurons can reduce highly palatable food intake by suppressing mesolimbic DA signaling.

Medial forebrain bundle lesions fail to structurally and functionally disconnect the ventral tegmental area from many ipsilateral forebrain nuclei: implications for the neural substrate of brain stimulation reward.

Science.gov (United States)

Simmons, J M; Ackermann, R F; Gallistel, C R

1998-10-15

Lesions in the medial forebrain bundle rostral to a stimulating electrode have variable effects on the rewarding efficacy of self-stimulation. We attempted to account for this variability by measuring the anatomical and functional effects of electrolytic lesions at the level of the lateral hypothalamus (LH) and by correlating these effects to postlesion changes in threshold pulse frequency (pps) for self-stimulation in the ventral tegmental area (VTA). We implanted True Blue in the VTA and compared cell labeling patterns in forebrain regions of intact and lesioned animals. We also compared stimulation-induced regional [14C]deoxyglucose (DG) accumulation patterns in the forebrains of intact and lesioned animals. As expected, postlesion threshold shifts varied: threshold pps remained the same or decreased in eight animals, increased by small but significant amounts in three rats, and increased substantially in six subjects. Unexpectedly, LH lesions did not anatomically or functionally disconnect all forebrain nuclei from the VTA. Most septal and preoptic regions contained equivalent levels of True Blue label in intact and lesioned animals. In both intact and lesioned groups, VTA stimulation increased metabolic activity in the fundus of the striatum (FS), the nucleus of the diagonal band, and the medial preoptic area. On the other hand, True Blue labeling demonstrated anatomical disconnection of the accumbens, FS, substantia innominata/magnocellular preoptic nucleus (SI/MA), and bed nucleus of the stria terminalis. [14C]DG autoradiography indicated functional disconnection of the lateral preoptic area and SI/MA. Correlations between patterns of True Blue labeling or [14C]deoxyglucose accumulation and postlesion shifts in threshold pulse frequency were weak and generally negative. These direct measures of connectivity concord with the behavioral measures in suggesting a diffuse net-like connection between forebrain nuclei and the VTA.

Epac Signaling Is Required for Cocaine-Induced Change in AMPA Receptor Subunit Composition in the Ventral Tegmental Area.

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Liu, Xiaojie; Chen, Yao; Tong, Jiaqing; Reynolds, Ashley M; Proudfoot, Sarah C; Qi, Jinshun; Penzes, Peter; Lu, Youming; Liu, Qing-Song

2016-04-27

Exchange protein directly activated by cAMP (Epac) and protein kinase A (PKA) are intracellular receptors for cAMP. Although PKA and its downstream effectors have been studied extensively in the context of drug addiction, whether and how Epac regulates cellular and behavioral effects of drugs of abuse remain essentially unknown. Epac is known to regulate AMPA receptor (AMPAR) trafficking. Previous studies have shown that a single cocaine exposure in vivo leads to an increase in GluA2-lacking AMPARs in dopamine neurons of the ventral tegmental area (VTA). We tested the hypothesis that Epac mediates cocaine-induced changes in AMPAR subunit composition in the VTA. We report that a single cocaine injection in vivo in wild-type mice leads to inward rectification of EPSCs and renders EPSCs sensitive to a GluA2-lacking AMPAR blocker in VTA dopamine neurons. The cocaine-induced increase in GluA2-lacking AMPARs was absent in Epac2-deficient mice but not in Epac1-deficient mice. In addition, activation of Epac with the selective Epac agonist 8-CPT-2Me-cAMP (8-CPT) recapitulated the cocaine-induced increase in GluA2-lacking AMPARs, and the effects of 8-CPT were mediated by Epac2. We also show that conditioned place preference to cocaine was impaired in Epac2-deficient mice and in mice in which Epac2 was knocked down in the VTA but was not significantly altered in Epac1-deficient mice. Together, these results suggest that Epac2 is critically involved in the cocaine-induced change in AMPAR subunit composition and drug-cue associative learning. Addictive drugs, such as cocaine, induce long-lasting adaptions in the reward circuits of the brain. A single intraperitoneal injection of cocaine leads to changes in the composition and property of the AMPAR that carries excitatory inputs to dopamine neurons. Here, we provide evidence that exchange protein directly activated by cAMP (Epac), a cAMP sensor protein, is required for the cocaine-induced changes of the AMPAR. We found that the

Short- and long-term modulation of synaptic inputs to brain reward areas by nicotine

NARCIS (Netherlands)

Fagen, Z.M.; Mansvelder, H.D.; Keath, R.; McGehee, D.S.

2003-01-01

Dopamine signaling in brain reward areas is a key element in the development of drug abuse and dependence. Recent anatomical and electrophysiological research has begun to elucidate both complexity and specificity In synaptic connections between ventral tegmental neurons and their inputs.

Neurotoxic lesions of the pedunculopontine tegmental nucleus impair the elaboration of postictal antinociception.

Science.gov (United States)

de Oliveira, Rithiele Cristina; de Oliveira, Ricardo; Falconi-Sobrinho, Luiz Luciano; Biagioni, Audrey Franceschi; Almada, Rafael Carvalho; Dos Anjos-Garcia, Tayllon; Bazaglia-de-Sousa, Guilherme; Khan, Asmat Ullah; Coimbra, Norberto Cysne

2018-05-12

Generalised tonic-clonic seizures, generated by abnormal neuronal hyper-activity, cause a significant and long-lasting increase in the nociceptive threshold. The pedunculopontine tegmental nucleus (PPTN) plays a crucial role in the regulation of seizures as well as the modulation of pain, but its role in postictal antinociceptive processes remains unclear. In the present study, we aimed to investigate the involvement of PPTN neurons in the postictal antinociception. Wistar rats had their tail-flick baseline recorded and were injected with ibotenic acid (1.0 μg/0.2 μL) into the PPTN, aiming to promote a local neurotoxic lesion. Five days after the neuronal damage, pentylenetetrazole (PTZ; 64 mg/kg) was intraperitoneally administered to induce tonic-clonic seizures. The tail-withdrawal latency was measured immediately after the seizures (0 min) and subsequently at 10-min intervals until 130 min after the seizures were induced pharmacologically. Ibotenic acid microinjected into the PPTN did not reduce the PTZ-induced seizure duration and severity, but it diminished the postictal antinociception from 0 to 130 min after the end of the PTZ-induced tonic-clonic seizures. These results suggest that the postictal antinociception depends on the PPTN neuronal cells integrity. Copyright © 2018 Elsevier Inc. All rights reserved.

Effects of insulin and leptin in the ventral tegmental area and arcuate hypothalamic nucleus on food intake and brain reward function in female rats.

Science.gov (United States)

Bruijnzeel, Adrie W; Corrie, Lu W; Rogers, Jessica A; Yamada, Hidetaka

2011-06-01

There is evidence for a role of insulin and leptin in food intake, but the effects of these adiposity signals on the brain reward system are not well understood. Furthermore, the effects of insulin and leptin on food intake in females are underinvestigated. These studies investigated the role of insulin and leptin in the ventral tegmental area (VTA) and the arcuate hypothalamic nucleus (Arc) on food intake and brain reward function in female rats. The intracranial self-stimulation procedure was used to assess the effects of insulin and leptin on the reward system. Elevations in brain reward thresholds are indicative of a decrease in brain reward function. The bilateral administration of leptin into the VTA (15-500 ng/side) or Arc (15-150 ng/side) decreased food intake for 72 h. The infusion of leptin into the VTA or Arc resulted in weight loss during the first 48 (VTA) or 24 h (Arc) after the infusions. The administration of insulin (0.005-5 mU/side) into the VTA or Arc decreased food intake for 24 h but did not affect body weights. The bilateral administration of low, but not high, doses of leptin (15 ng/side) or insulin (0.005 mU/side) into the VTA elevated brain reward thresholds. Neither insulin nor leptin in the Arc affected brain reward thresholds. These studies suggest that a small increase in leptin or insulin levels in the VTA leads to a decrease in brain reward function. A relatively large increase in insulin or leptin levels in the VTA or Arc decreases food intake. Published by Elsevier B.V.

Ventral tegmental area disruption selectively affects CA1/CA2 but not CA3 place fields during a differential reward working memory task.

Science.gov (United States)

Martig, Adria K; Mizumori, Sheri J Y

2011-02-01

Hippocampus (HPC) receives dopaminergic (DA) projections from the ventral tegmental area (VTA) and substantia nigra. These inputs appear to provide a modulatory signal that influences HPC dependent behaviors and place fields. We examined how efferent projections from VTA to HPC influence spatial working memory and place fields when the reward context changes. CA1 and CA3 process environmental context changes differently and VTA preferentially innervates CA1. Given these anatomical data and electrophysiological evidence that implicate DA in reward processing, we predicted that CA1 place fields would respond more strongly to both VTA disruption and changes in the reward context than CA3 place fields. Rats (N = 9) were implanted with infusion cannula targeting VTA and recording tetrodes aimed at HPC. Then they were tested on a differential reward, win-shift working memory task. One recording session consisted of 5 baseline and 5 manipulation trials during which place cells in CA1/CA2 (N = 167) and CA3 (N = 94) were recorded. Prior to manipulation trials rats were infused with either baclofen or saline and then subjected to control or reward conditions during which the learned locations of large and small reward quantities were reversed. VTA disruption resulted in an increase in errors, and in CA1/CA2 place field reorganization. There were no changes in any measures of CA3 place field stability during VTA disruption. Reward manipulations did not affect performance or place field stability in CA1/CA2 or CA3; however, changes in the reward locations "rescued" performance and place field stability in CA1/CA2 when VTA activity was compromised, perhaps by trigging compensatory mechanisms. These data support the hypothesis that VTA contributes to spatial working memory performance perhaps by maintaining place field stability selectively in CA1/CA2. Copyright © 2009 Wiley-Liss, Inc.

Ghrelin signaling in the ventral tegmental area mediates both reward-based feeding and fasting-induced hyperphagia on high-fat diet.

Science.gov (United States)

Wei, X J; Sun, B; Chen, K; Lv, B; Luo, X; Yan, J Q

2015-08-06

Ghrelin is a potent orexigenic hormone that acts in the central nervous system to stimulate food intake via the growth hormone secretagogue receptor (GHSR) that is abundantly expressed in the ventral tegmental area (VTA). Not only does ghrelin modulate feeding behavior via a homeostatic mechanism, but numerous studies have identified ghrelin as a key regulator of reward-based hedonic feeding behaviors. Nutritional states influence ghrelin and GHSR expression as well as the behavioral sensitivity to reward-inducing stimuli. In the current study, we examined the role of ghrelin at the VTA level in food intake in two different nutritional states, satiety and hunger, by using a restricted feeding model. In this model, rats were conditioned to a daily 3-h (h) feeding session on standard chow for 10days and a high-fat diet (HFD) was supplied either in the third hour after 2h of chow diet intake, or at the beginning of a daily meal on the test day. We found that intra-VTA microinjection of 1, 2, and 4μg of ghrelin, induced a dose-related increase of 1h of reward-based feeding on HFD in sated rats, as well as a 24-h body weight gain. The overconsumption stimulated by ghrelin could be attenuated by 10μg of direct infusion of the ghrelin receptor antagonist D-Lys3-GHRP-6 into the VTA. Moreover, our data showed that the injection of 1, 2, and 4μg of ghrelin in the VTA, enhanced fasting-induced hyperphagia on HFD in a dose-related manner following a 21-h food restriction as well as a 24-h body weight gain. Conversely, hyperphagia on HFD that is potentiated by ghrelin could be blocked by pretreatment with a 10-μg D-Lys3-GHRP-6 intra-VTA microinjection. Collectively, these data demonstrate that ghrelin signaling at the VTA level mediates both reward-based eating and fasting-induced hyperphagia and provides a primary target for the control of the intake of rewarding food. Copyright © 2015 IBRO. Published by Elsevier Ltd. All rights reserved.

Neurophysiological evidence for the presence of cannabinoid CB1 receptors in the laterodorsal tegmental nucleus

DEFF Research Database (Denmark)

Soni, Neeraj; Satpathy, Shankha; Kohlmeier, Kristi Anne

2014-01-01

Marijuana, which acts within the endocannabinoid (eCB) system as an agonist of the cannabinoid type 1 receptor (CB1R), exhibits addictive properties and has powerful actions on the state of arousal of an organism. The laterodorsal tegmental nucleus (LDT), as a component of the reticular activating...... the firing frequency and synaptic activity of neurons in this nucleus. Therefore, endogenous eCB transmission could play a role in processes involving the LDT, such as cortical activation and motivated behaviours and, further, behavioural actions of marijuana are probably mediated, in part, via cellular...

NMDA receptors regulate nicotine-enhanced brain reward function and intravenous nicotine self-administration: role of the ventral tegmental area and central nucleus of the amygdala.

Science.gov (United States)

Kenny, Paul J; Chartoff, Elena; Roberto, Marisa; Carlezon, William A; Markou, Athina

2009-01-01

Nicotine is considered an important component of tobacco responsible for the smoking habit in humans. Nicotine increases glutamate-mediated transmission throughout brain reward circuitries. This action of nicotine could potentially contribute to its intrinsic rewarding and reward-enhancing properties, which motivate consumption of the drug. Here we show that the competitive N-methyl-D-aspartate (NMDA) receptor antagonist LY235959 (0.5-2.5 mg per kg) abolished nicotine-enhanced brain reward function, reflected in blockade of the lowering of intracranial self-stimulation (ICSS) thresholds usually observed after experimenter-administered (0.25 mg per kg) or intravenously self-administered (0.03 mg per kg per infusion) nicotine injections. The highest LY235959 dose (5 mg per kg) tested reversed the hedonic valence of nicotine from positive to negative, reflected in nicotine-induced elevations of ICSS thresholds. LY235959 doses that reversed nicotine-induced lowering of ICSS thresholds also markedly decreased nicotine self-administration without altering responding for food reinforcement, whereas the alpha-amino-3-hydroxy-5-methyl-4-isoxazole propionic acid receptor antagonist NBQX had no effects on nicotine intake. In addition, nicotine self-administration upregulated NMDA receptor subunit expression in the central nucleus of the amygdala (CeA) and ventral tegmental area (VTA), suggesting important interactions between nicotine and the NMDA receptor. Furthermore, nicotine (1 microM) increased NMDA receptor-mediated excitatory postsynaptic currents in rat CeA slices, similar to its previously described effects in the VTA. Finally, infusion of LY235959 (0.1-10 ng per side) into the CeA or VTA decreased nicotine self-administration. Taken together, these data suggest that NMDA receptors, including those in the CeA and VTA, gate the magnitude and valence of the effects of nicotine on brain reward systems, thereby regulating motivation to consume the drug.

The Appetite-Inducing Peptide, Ghrelin, Induces Intracellular Store-Mediated Rises in Calcium in Addiction and Arousal-Related Laterodorsal Tegmental Neurons in Mouse Brain Slices

DEFF Research Database (Denmark)

Hauberg, Katrine; Kohlmeier, Kristi Anne

2015-01-01

Ghrelin, a gut and brain peptide, has recently been shown to be involved in motivated behavior and regulation of the sleep and wakefulness cycle. The laterodorsal tegmental nucleus (LDT) is involved in appetitive behavior and control of the arousal state of an organism, and accordingly, behaviora...

Synaptic neurotransmission depression in ventral tegmental dopamine neurons and cannabinoid-associated addictive learning.

Science.gov (United States)

Liu, Zhiqiang; Han, Jing; Jia, Lintao; Maillet, Jean-Christian; Bai, Guang; Xu, Lin; Jia, Zhengping; Zheng, Qiaohua; Zhang, Wandong; Monette, Robert; Merali, Zul; Zhu, Zhou; Wang, Wei; Ren, Wei; Zhang, Xia

2010-12-20

Drug addiction is an association of compulsive drug use with long-term associative learning/memory. Multiple forms of learning/memory are primarily subserved by activity- or experience-dependent synaptic long-term potentiation (LTP) and long-term depression (LTD). Recent studies suggest LTP expression in locally activated glutamate synapses onto dopamine neurons (local Glu-DA synapses) of the midbrain ventral tegmental area (VTA) following a single or chronic exposure to many drugs of abuse, whereas a single exposure to cannabinoid did not significantly affect synaptic plasticity at these synapses. It is unknown whether chronic exposure of cannabis (marijuana or cannabinoids), the most commonly used illicit drug worldwide, induce LTP or LTD at these synapses. More importantly, whether such alterations in VTA synaptic plasticity causatively contribute to drug addictive behavior has not previously been addressed. Here we show in rats that chronic cannabinoid exposure activates VTA cannabinoid CB1 receptors to induce transient neurotransmission depression at VTA local Glu-DA synapses through activation of NMDA receptors and subsequent endocytosis of AMPA receptor GluR2 subunits. A GluR2-derived peptide blocks cannabinoid-induced VTA synaptic depression and conditioned place preference, i.e., learning to associate drug exposure with environmental cues. These data not only provide the first evidence, to our knowledge, that NMDA receptor-dependent synaptic depression at VTA dopamine circuitry requires GluR2 endocytosis, but also suggest an essential contribution of such synaptic depression to cannabinoid-associated addictive learning, in addition to pointing to novel pharmacological strategies for the treatment of cannabis addiction.

Symmetrical central tegmental tract (CTT) hyperintense lesions on magnetic resonance imaging in children

International Nuclear Information System (INIS)

Yoshida, Shoko; Hayakawa, Katsumi; Yamamoto, Akira; Aida, Noriko; Okano, Souzo; Matsushita, Hiroko; Kanda, Toyoko; Yamori, Yuriko; Yoshida, Naoko; Hirota, Haruyo

2009-01-01

The central tegmental tract (CTT) is mainly the extrapyramidal tract connecting between the red nucleus and the inferior olivary nucleus. There are only a few case reports describing CTT abnormalities on magnetic resonance imaging (MRI) in children. Our purpose was to evaluate the frequency of CTT lesions and their characteristics on MRI, and to correlate the MR imaging findings with clinical features. We reviewed retrospectively the MR images of 392 children (215 boys and 177 girls) ranging in age from 1 to 6 years. To evaluate symmetrical CTT hyperintense lesions, we defined a CTT lesion as an area of bilateral symmetrical hyperintensity in the tegmentum pontis on both T2-weighted images and diffusion-weighted images in more than two slices. We measured the ADC (apparent diffusion coefficient) values of symmetrical CTT hyperintensity, and compared them with those of children without CTT abnormality. CTT lesions were detected in 20 (5.1%) of the 392 children. The mean ADC value for these 20 children was significantly lower than that of the normal CTT (p<0.001). On MR imaging, other than CTT lesions, associated parenchymal lesion included: none (n=6); other abnormalities, including periventricular leukomalacia (n=3); thin corpus callosum (n=3); ventricular dilatation (n=2); encephalopathy (n=2). Clinically, cerebral palsy was the most frequent clinical diagnosis (n=6), accounting for 30%, which was significantly more frequent than the prevalence of cerebral palsy among children without CTT lesions (13%) (n<0.05). CTT lesions were detected in 5.1% of all the children examined. Cerebral palsy was the most frequent clinical diagnosis. (orig.)

Symmetrical central tegmental tract (CTT) hyperintense lesions on magnetic resonance imaging in children

Energy Technology Data Exchange (ETDEWEB)

Yoshida, Shoko; Hayakawa, Katsumi; Yamamoto, Akira [Kyoto City Hospital, Department of Radiology, Kyoto (Japan); Aida, Noriko [Kanagawa Children' s Medical Center, Department of Radiology, Kyoto (Japan); Okano, Souzo; Matsushita, Hiroko [Kyoto City Hospital, Department of Pediatrics, Kyoto (Japan); Kanda, Toyoko; Yamori, Yuriko; Yoshida, Naoko; Hirota, Haruyo [St. Joseph Hospital for Handicapped Children, Department of Pediatric Neurology, Kyoto (Japan)

2009-02-15

The central tegmental tract (CTT) is mainly the extrapyramidal tract connecting between the red nucleus and the inferior olivary nucleus. There are only a few case reports describing CTT abnormalities on magnetic resonance imaging (MRI) in children. Our purpose was to evaluate the frequency of CTT lesions and their characteristics on MRI, and to correlate the MR imaging findings with clinical features. We reviewed retrospectively the MR images of 392 children (215 boys and 177 girls) ranging in age from 1 to 6 years. To evaluate symmetrical CTT hyperintense lesions, we defined a CTT lesion as an area of bilateral symmetrical hyperintensity in the tegmentum pontis on both T2-weighted images and diffusion-weighted images in more than two slices. We measured the ADC (apparent diffusion coefficient) values of symmetrical CTT hyperintensity, and compared them with those of children without CTT abnormality. CTT lesions were detected in 20 (5.1%) of the 392 children. The mean ADC value for these 20 children was significantly lower than that of the normal CTT (p<0.001). On MR imaging, other than CTT lesions, associated parenchymal lesion included: none (n=6); other abnormalities, including periventricular leukomalacia (n=3); thin corpus callosum (n=3); ventricular dilatation (n=2); encephalopathy (n=2). Clinically, cerebral palsy was the most frequent clinical diagnosis (n=6), accounting for 30%, which was significantly more frequent than the prevalence of cerebral palsy among children without CTT lesions (13%) (n<0.05). CTT lesions were detected in 5.1% of all the children examined. Cerebral palsy was the most frequent clinical diagnosis. (orig.)

Synaptic neurotransmission depression in ventral tegmental dopamine neurons and cannabinoid-associated addictive learning.

Directory of Open Access Journals (Sweden)

Zhiqiang Liu

2010-12-01

Full Text Available Drug addiction is an association of compulsive drug use with long-term associative learning/memory. Multiple forms of learning/memory are primarily subserved by activity- or experience-dependent synaptic long-term potentiation (LTP and long-term depression (LTD. Recent studies suggest LTP expression in locally activated glutamate synapses onto dopamine neurons (local Glu-DA synapses of the midbrain ventral tegmental area (VTA following a single or chronic exposure to many drugs of abuse, whereas a single exposure to cannabinoid did not significantly affect synaptic plasticity at these synapses. It is unknown whether chronic exposure of cannabis (marijuana or cannabinoids, the most commonly used illicit drug worldwide, induce LTP or LTD at these synapses. More importantly, whether such alterations in VTA synaptic plasticity causatively contribute to drug addictive behavior has not previously been addressed. Here we show in rats that chronic cannabinoid exposure activates VTA cannabinoid CB1 receptors to induce transient neurotransmission depression at VTA local Glu-DA synapses through activation of NMDA receptors and subsequent endocytosis of AMPA receptor GluR2 subunits. A GluR2-derived peptide blocks cannabinoid-induced VTA synaptic depression and conditioned place preference, i.e., learning to associate drug exposure with environmental cues. These data not only provide the first evidence, to our knowledge, that NMDA receptor-dependent synaptic depression at VTA dopamine circuitry requires GluR2 endocytosis, but also suggest an essential contribution of such synaptic depression to cannabinoid-associated addictive learning, in addition to pointing to novel pharmacological strategies for the treatment of cannabis addiction.

Synaptic Neurotransmission Depression in Ventral Tegmental Dopamine Neurons and Cannabinoid-Associated Addictive Learning

Science.gov (United States)

Liu, Zhiqiang; Han, Jing; Jia, Lintao; Maillet, Jean-Christian; Bai, Guang; Xu, Lin; Jia, Zhengping; Zheng, Qiaohua; Zhang, Wandong; Monette, Robert; Merali, Zul; Zhu, Zhou; Wang, Wei; Ren, Wei; Zhang, Xia

2010-01-01

Drug addiction is an association of compulsive drug use with long-term associative learning/memory. Multiple forms of learning/memory are primarily subserved by activity- or experience-dependent synaptic long-term potentiation (LTP) and long-term depression (LTD). Recent studies suggest LTP expression in locally activated glutamate synapses onto dopamine neurons (local Glu-DA synapses) of the midbrain ventral tegmental area (VTA) following a single or chronic exposure to many drugs of abuse, whereas a single exposure to cannabinoid did not significantly affect synaptic plasticity at these synapses. It is unknown whether chronic exposure of cannabis (marijuana or cannabinoids), the most commonly used illicit drug worldwide, induce LTP or LTD at these synapses. More importantly, whether such alterations in VTA synaptic plasticity causatively contribute to drug addictive behavior has not previously been addressed. Here we show in rats that chronic cannabinoid exposure activates VTA cannabinoid CB1 receptors to induce transient neurotransmission depression at VTA local Glu-DA synapses through activation of NMDA receptors and subsequent endocytosis of AMPA receptor GluR2 subunits. A GluR2-derived peptide blocks cannabinoid-induced VTA synaptic depression and conditioned place preference, i.e., learning to associate drug exposure with environmental cues. These data not only provide the first evidence, to our knowledge, that NMDA receptor-dependent synaptic depression at VTA dopamine circuitry requires GluR2 endocytosis, but also suggest an essential contribution of such synaptic depression to cannabinoid-associated addictive learning, in addition to pointing to novel pharmacological strategies for the treatment of cannabis addiction. PMID:21187978

Pedunculopontine tegmental nucleus lesions impair stimulus--reward learning in autoshaping and conditioned reinforcement paradigms.

Science.gov (United States)

Inglis, W L; Olmstead, M C; Robbins, T W

2000-04-01

The role of the pedunculopontine tegmental nucleus (PPTg) in stimulus-reward learning was assessed by testing the effects of PPTg lesions on performance in visual autoshaping and conditioned reinforcement (CRf) paradigms. Rats with PPTg lesions were unable to learn an association between a conditioned stimulus (CS) and a primary reward in either paradigm. In the autoshaping experiment, PPTg-lesioned rats approached the CS+ and CS- with equal frequency, and the latencies to respond to the two stimuli did not differ. PPTg lesions also disrupted discriminated approaches to an appetitive CS in the CRf paradigm and completely abolished the acquisition of responding with CRf. These data are discussed in the context of a possible cognitive function of the PPTg, particularly in terms of lesion-induced disruptions of attentional processes that are mediated by the thalamus.

General, kappa, delta and mu opioid receptor antagonists mediate feeding elicited by the GABA-B agonist baclofen in the ventral tegmental area and nucleus accumbens shell in rats: reciprocal and regional interactions.

Science.gov (United States)

Miner, Patricia; Shimonova, Lyudmila; Khaimov, Arthur; Borukhova, Yaffa; Ilyayeva, Ester; Ranaldi, Robert; Bodnar, Richard J

2012-03-14

Food intake is significantly increased following administration of agonists of GABA and opioid receptors into the nucleus accumbens shell (NACs) and ventral tegmental area (VTA). GABA-A or GABA-B receptor antagonist pretreatment within the VTA or NACs differentially affects mu-opioid agonist-induced feeding elicited from the same site. Correspondingly, general or selective opioid receptor antagonist pretreatment within the VTA or NACs differentially affects GABA agonist-induced feeding elicited from the same site. Regional interactions have been evaluated in feeding studies by administering antagonists in one site prior to agonist administration in a second site. Thus, opioid antagonist-opioid agonist and GABA antagonist-GABA agonist feeding interactions have been identified between the VTA and NACs. However, pretreatment with GABA-A or GABA-B receptor antagonists in the VTA failed to affect mu opioid agonist-induced feeding elicited from the NACs, and correspondingly, these antagonists administered in the NACs failed to affect mu opioid-induced feeding elicited from the VTA. To evaluate whether regional and reciprocal VTA and NACs feeding interactions occur for opioid receptor modulation of GABA agonist-mediated feeding, the present study examined whether feeding elicited by the GABA-B agonist, baclofen microinjected into the NACs was dose-dependently blocked by pretreatment with general (naltrexone: NTX), mu (beta-funaltrexamine: BFNA), kappa (nor-binaltorphamine: NBNI) or delta (naltrindole: NTI) opioid antagonists in the VTA, and correspondingly, whether VTA baclofen-induced feeding was dose-dependently blocked by NACs pretreatment with NTX, BFNA, NBNI or NTI in rats. Bilateral pairs of cannulae aimed at the VTA and NACs were stereotaxically implanted in rats, and their food intakes were assessed following vehicle and baclofen (200 ng) in each site. Baclofen produced similar magnitudes of increased food intake following VTA and NACs treatment. Baclofen

Striatal and Tegmental Neurons Code Critical Signals for Temporal-Difference Learning of State Value in Domestic Chicks

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Chentao Wen

2016-11-01

Full Text Available To ensure survival, animals must update the internal representations of their environment in a trial-and-error fashion. Psychological studies of associative learning and neurophysiological analyses of dopaminergic neurons have suggested that this updating process involves the temporal-difference (TD method in the basal ganglia network. However, the way in which the component variables of the TD method are implemented at the neuronal level is unclear. To investigate the underlying neural mechanisms, we trained domestic chicks to associate color cues with food rewards. We recorded neuronal activities from the medial striatum or tegmentum in a freely behaving condition and examined how reward omission changed neuronal firing. To compare neuronal activities with the signals assumed in the TD method, we simulated the behavioral task in the form of a finite sequence composed of discrete steps of time. The three signals assumed in the simulated task were the prediction signal, the target signal for updating, and the TD-error signal. In both the medial striatum and tegmentum, the majority of recorded neurons were categorized into three types according to their fitness for three models, though these neurons tended to form a continuum spectrum without distinct differences in the firing rate. Specifically, two types of striatal neurons successfully mimicked the target signal and the prediction signal. A linear summation of these two types of striatum neurons was a good fit for the activity of one type of tegmental neurons mimicking the TD-error signal. The present study thus demonstrates that the striatum and tegmentum can convey the signals critically required for the TD method. Based on the theoretical and neurophysiological studies, together with tract-tracing data, we propose a novel model to explain how the convergence of signals represented in the striatum could lead to the computation of TD error in tegmental dopaminergic neurons.

Effects of BDNF receptor antagonist on the severity of physical and psychological dependence, morphine-induced locomotor sensitization and the ventral tegmental area-nucleus accumbens BDNF levels in morphine- dependent and withdrawn rats.

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Khalil-Khalili, Masoumeh; Rashidy-Pour, Ali; Bandegi, Ahmad Reza; Yousefi, Behpoor; Jorjani, Hassan; Miladi-Gorji, Hossein

2018-03-06

This study examined the effects of systemic administration of the TrkB receptor antagonist (ANA-12) on the severity of physical and psychological dependence and morphine-induced locomotor sensitization, the ventral tegmental area (VTA)-nucleus accumbens (NAc) BDNF levels in morphine-dependent and withdrawn rats. Rats were injected with bi-daily doses (10 mg/kg, at 12 h intervals) of morphine for 10 days. Then, rats were tested for naloxone-precipitated morphine withdrawal signs, the anxiety (the elevated plus maze-EPM) after the last morphine injection and injection of ANA12 (ip). Also, morphine-induced locomotor sensitization was evaluated after morphine challenge followed by an injection of ANA-12 in morphine-withdrawn rats. The VTA-NAc BDNF levels were assessed in morphine-dependent and withdrawn rats. The overall Gellert-Holtzman score was significantly higher in morphine-dependent rats receiving ANA-12 than in those receiving saline. Also, the percentage of time spent in the open arms in control and morphine-dependent rats receiving ANA-12 were higher compared to the Cont/Sal and D/Sal rats, respectively. There was no significant difference in the locomotor activity and the VTA-NAc BDNF levels between D/Sal/morphine and D/ANA-12/morphine groups after morphine withdrawal. We conclude that the systemic administration of ANA-12 exacerbates the severity of physical dependence on morphine and partially attenuates the anxiety-like behavior in morphine-dependent rats. However, ANA-12 did not affect morphine-induced locomotor sensitization and the VTA-NAc BDNF levels in morphine-dependent and withdrawn rats. Copyright © 2017 Elsevier B.V. All rights reserved.

Knockdown of ventral tegmental area mu-opioid receptors in rats prevents effects of social defeat stress: Implications for amphetamine cross-sensitization, social avoidance, weight regulation and expression of brain-derived neurotrophic factor

Science.gov (United States)

Johnston, Caitlin E.; Herschel, Daniel; Lasek, Amy W.; Hammer, Ronald P.; Nikulina, Ella M.

2014-01-01

Social defeat stress causes social avoidance and long-lasting cross-sensitization to psychostimulants, both of which are associated with increased brain-derived neurotrophic factor (BDNF) expression in the ventral tegmental area (VTA). Moreover, social stress upregulates VTA mu-opioid receptor (MOR) mRNA. In the VTA, MOR activation inhibits GABA neurons to disinhibit VTA dopamine neurons, thus providing a role for VTA MORs in the regulation of psychostimulant sensitization. The present study determined the effect of lentivirus-mediated MOR knockdown in the VTA on the consequences of intermittent social defeat stress, a salient and profound stressor in humans and rodents. Social stress exposure induced social avoidance and attenuated weight gain in animals with non-manipulated VTA MORs, but both these effects were prevented by VTA MOR knockdown. Rats with non-manipulated VTA MOR expression exhibited cross-sensitization to amphetamine challenge (1.0 mg/kg, i.p.), evidenced by a significant augmentation of locomotion. By contrast, knockdown of VTA MORs prevented stress-induced cross-sensitization without blunting the locomotor-activating effects of amphetamine. At the time point corresponding to amphetamine challenge, immunohistochemical analysis was performed to examine the effect of stress on VTA BDNF expression. Prior stress exposure increased VTA BDNF expression in rats with non-manipulated VTA MOR expression, while VTA MOR knockdown prevented stress-induced expression of VTA BDNF. Taken together, these results suggest that upregulation of VTA MOR is necessary for the behavioral and biochemical changes induced by social defeat stress. Elucidating VTA MOR regulation of stress effects on the mesolimbic system may provide new therapeutic targets for treating stress-induced vulnerability to substance abuse. PMID:25446676

Destruction of the medial forebrain bundle caudal to the site of stimulation reduces rewarding efficacy but destruction rostrally does not.

Science.gov (United States)

Gallistel, C R; Leon, M; Lim, B T; Sim, J C; Waraczynski, M

1996-08-01

Rats with an electrode in the medial forebrain bundle (MFB) in or near the ventral tegmental area and another at the level of the rostral hypothalamus sustained large electrolytic lesions at either the rostral or the caudal electrode. The rewarding efficacy of stimulation through the other electrode was determined before and after the lesion. Massive damage to the MFB in the rostral lateral hypothalamus (LH) generally had little effect on the rewarding efficacy of more caudal stimulation, whereas large lesions in the caudal MFB generally reduced the rewarding efficacy of LH stimulation by 35-60%. Similar reductions were produced by knife cuts in the caudal MFB. These results appear to be inconsistent with the hypothesis that the reward fibers consist either of descending or ascending fibers coursing in or near the MFB. It is suggested that the reward fibers are collaterals from neurons with both their somata and their behaviorally significant terminals located primarily in the midbrain.

The Lateral Habenula and Its Input to the Rostromedial Tegmental Nucleus Mediates Outcome-Specific Conditioned Inhibition.

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Laurent, Vincent; Wong, Felix L; Balleine, Bernard W

2017-11-08

Animals can readily learn that stimuli predict the absence of specific appetitive outcomes; however, the neural substrates underlying such outcome-specific conditioned inhibition remain largely unexplored. Here, using female and male rats as subjects, we examined the involvement of the lateral habenula (LHb) and of its inputs onto the rostromedial tegmental nucleus (RMTg) in inhibitory learning. In these experiments, we used backward conditioning and contingency reversal to establish outcome-specific conditioned inhibitors for two distinct appetitive outcomes. Then, using the Pavlovian-instrumental transfer paradigm, we assessed the effects of manipulations of the LHb and the LHb-RMTg pathway on that inhibitory encoding. In control animals, we found that an outcome-specific conditioned inhibitor biased choice away from actions delivering that outcome and toward actions earning other outcomes. Importantly, this bias was abolished by both electrolytic lesions of the LHb and selective ablation of LHb neurons using Cre-dependent Caspase3 expression in Cre-expressing neurons projecting to the RMTg. This deficit was specific to conditioned inhibition; an excitatory predictor of a specific outcome-biased choice toward actions delivering the same outcome to a similar degree whether the LHb or the LHb-RMTg network was intact or not. LHb lesions also disrupted the ability of animals to inhibit previously encoded stimulus-outcome contingencies after their reversal, pointing to a critical role of the LHb and of its inputs onto the RMTg in outcome-specific conditioned inhibition in appetitive settings. These findings are consistent with the developing view that the LHb promotes a negative reward prediction error in Pavlovian conditioning. SIGNIFICANCE STATEMENT Stimuli that positively or negatively predict rewarding outcomes influence choice between actions that deliver those outcomes. Previous studies have found that a positive predictor of a specific outcome biases choice

Brainstem projections of neurons located in various subdivisions of the dorsolateral hypothalamic area – an anterograde tract-tracing study

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Rege Sugárka Papp

2014-05-01

Full Text Available The projections from the dorsolateral hypothalamic area (DLH to the lower brainstem have been investigated by using biotinylated dextran amine (BDA, an anterograde tracer in rats. The DLH can be divided into 3 areas (dorsomedial hypothalamus, perifornical area, lateral hypothalamic area, and further subdivided into 8 subdivisions. After unilateral stereotaxic injections of BDA into individual DLH subdivisions, the correct sites of injections were controlled histologically, and the distribution patterns of BDA-positive fibers were mapped on serial sections between the hypothalamus and spinal cord in 22 rats. BDA-labeled fibers were observable over 100 different brainstem areas, nuclei or subdivisions. Injections into the 8 DLH subdivisions established distinct topographical patterns. In general, the density of labeled fibers was low in the lower brainstem. High density of fibers was seen only 4 of the 116 areas: in the lateral and ventrolateral parts of the periaqueductal gray, the Barrington’s and the pedunculopontine tegmental nuclei. All of the biogenic amine cell groups in the lower brainstem (9 noradrenaline, 3 adrenaline and 9 serotonin cell groups received labeled fibers, some of them from all, or at least 7 DLH subdivisions, mainly from perifornical and ventral lateral hypothalamic neurons. Some of the tegmental nuclei and nuclei of the reticular formation were widely innervated, although the density of the BDA-labeled fibers was generally low. No definitive descending BDA-positive pathway, but long-run solitaire BDA-labeled fibers were seen in the lower brainstem. These descending fibers joined some of the large tracts or fasciculi in the brainstem. The distribution pattern of BDA-positive fibers of DLH origin throughout the lower brainstem was comparable to patterns of previously published orexin- or melanin-concentrating hormone-immunoreactive fibers with somewhat differences.

Food-Related Odors Activate Dopaminergic Brain Areas

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Agnieszka Sorokowska

2017-12-01

Full Text Available Food-associated cues of different sensory categories have often been shown to be a potent elicitor of cerebral activity in brain reward circuits. Smells influence and modify the hedonic qualities of eating experience, and in contrast to smells not associated with food, perception of food-associated odors may activate dopaminergic brain areas. In this study, we aimed to verify previous findings related to the rewarding value of food-associated odors by means of an fMRI design involving carefully preselected odors of edible and non-edible substances. We compared activations generated by three food and three non-food odorants matching in terms of intensity, pleasantness and trigeminal qualities. We observed that for our mixed sample of 30 hungry and satiated participants, food odors generated significantly higher activation in the anterior cingulate cortex (right and left, insula (right, and putamen (right than non-food odors. Among hungry subjects, regardless of the odor type, we found significant activation in the ventral tegmental area in response to olfactory stimulation. As our stimuli were matched in terms of various perceptual qualities, this result suggests that edibility of an odor source indeed generates specific activation in dopaminergic brain areas.

Measuring the effectiveness of protected area networks in reducing deforestation.

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Andam, Kwaw S; Ferraro, Paul J; Pfaff, Alexander; Sanchez-Azofeifa, G Arturo; Robalino, Juan A

2008-10-21

Global efforts to reduce tropical deforestation rely heavily on the establishment of protected areas. Measuring the effectiveness of these areas is difficult because the amount of deforestation that would have occurred in the absence of legal protection cannot be directly observed. Conventional methods of evaluating the effectiveness of protected areas can be biased because protection is not randomly assigned and because protection can induce deforestation spillovers (displacement) to neighboring forests. We demonstrate that estimates of effectiveness can be substantially improved by controlling for biases along dimensions that are observable, measuring spatial spillovers, and testing the sensitivity of estimates to potential hidden biases. We apply matching methods to evaluate the impact on deforestation of Costa Rica's renowned protected-area system between 1960 and 1997. We find that protection reduced deforestation: approximately 10% of the protected forests would have been deforested had they not been protected. Conventional approaches to evaluating conservation impact, which fail to control for observable covariates correlated with both protection and deforestation, substantially overestimate avoided deforestation (by over 65%, based on our estimates). We also find that deforestation spillovers from protected to unprotected forests are negligible. Our conclusions are robust to potential hidden bias, as well as to changes in modeling assumptions. Our results show that, with appropriate empirical methods, conservation scientists and policy makers can better understand the relationships between human and natural systems and can use this to guide their attempts to protect critical ecosystem services.

Designated rooting areas to reduce pasture damage by pregnant sows

NARCIS (Netherlands)

Mheen, van der H.; Spoolder, H.A.M.

2005-01-01

To assess whether rooting damage by pregnant sows can be reduced by offering a designated area for wallowing and foraging, four groups of four sows each were subjected to four treatments, during eight periods in a 4 × 4 Latin square designed experiment. During each period, each group was given

Brain reward circuitry beyond the mesolimbic dopamine system: a neurobiological theory.

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Ikemoto, Satoshi

2010-11-01

Reductionist attempts to dissect complex mechanisms into simpler elements are necessary, but not sufficient for understanding how biological properties like reward emerge out of neuronal activity. Recent studies on intracranial self-administration of neurochemicals (drugs) found that rats learn to self-administer various drugs into the mesolimbic dopamine structures-the posterior ventral tegmental area, medial shell nucleus accumbens and medial olfactory tubercle. In addition, studies found roles of non-dopaminergic mechanisms of the supramammillary, rostromedial tegmental and midbrain raphe nuclei in reward. To explain intracranial self-administration and related effects of various drug manipulations, I outlined a neurobiological theory claiming that there is an intrinsic central process that coordinates various selective functions (including perceptual, visceral, and reinforcement processes) into a global function of approach. Further, this coordinating process for approach arises from interactions between brain structures including those structures mentioned above and their closely linked regions: the medial prefrontal cortex, septal area, ventral pallidum, bed nucleus of stria terminalis, preoptic area, lateral hypothalamic areas, lateral habenula, periaqueductal gray, laterodorsal tegmental nucleus and parabrachical area. Published by Elsevier Ltd.

Reducing biosolids disposal costs using land application in forested areas

International Nuclear Information System (INIS)

Huffines, R.L.

1995-01-01

Switching biosolids land application from a reclamation site to a forested site significantly reduced the cost of biosolids disposal at the Savannah River Site. Previous beneficial reuse programs focused on reclamation of existing borrow pits. While extremely beneficial, this program became very costly due to the regulatory requirements for groundwater monitoring, soil monitoring and frequent biosolids analyses. A new program was developed to reuse biosolids in forested areas where the biosolids could be used as a soil conditioner and fertilizer to enhance timber yield. The forested land application site was designed so that groundwater monitoring and soil monitoring could be eliminated while biosolids monitoring and site maintenance were minimized. Monitoring costs alone were reduced by 80%. Capital costs for site preparation were also significantly reduced since there was no longer a need for expensive groundwater monitoring wells

A maternal "junk-food" diet reduces sensitivity to the opioid antagonist naloxone in offspring postweaning.

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Gugusheff, Jessica R; Ong, Zhi Yi; Muhlhausler, Beverly S

2013-03-01

Perinatal exposure to a maternal "junk-food" diet has been demonstrated to increase the preference for palatable diets in adult offspring. We aimed to determine whether this increased preference could be attributed to changes in μ-opioid receptor expression within the mesolimbic reward pathway. We report here that mRNA expression of the μ-opioid receptor in the ventral tegmental area (VTA) at weaning was 1.4-fold (males) and 1.9-fold (females) lower in offspring of junk-food (JF)-fed rat dams than in offspring of dams fed a standard rodent diet (control) (Pjunk-food diet results in early desensitization of the opioid system which may explain the increased preference for junk food in these offspring.

A Neural Correlate of Predicted and Actual Reward-Value Information in Monkey Pedunculopontine Tegmental and Dorsal Raphe Nucleus during Saccade Tasks

Science.gov (United States)

Okada, Ken-ichi; Nakamura, Kae; Kobayashi, Yasushi

2011-01-01

Dopamine, acetylcholine, and serotonin, the main modulators of the central nervous system, have been proposed to play important roles in the execution of movement, control of several forms of attentional behavior, and reinforcement learning. While the response pattern of midbrain dopaminergic neurons and its specific role in reinforcement learning have been revealed, the role of the other neuromodulators remains rather elusive. Here, we review our recent studies using extracellular recording from neurons in the pedunculopontine tegmental nucleus, where many cholinergic neurons exist, and the dorsal raphe nucleus, where many serotonergic neurons exist, while monkeys performed eye movement tasks to obtain different reward values. The firing patterns of these neurons are often tonic throughout the task period, while dopaminergic neurons exhibited a phasic activity pattern to the task event. The different modulation patterns, together with the activity of dopaminergic neurons, reveal dynamic information processing between these different neuromodulator systems. PMID:22013541

Age-related changes in nicotine response of cholinergic and non-cholinergic laterodorsal tegmental neurons: implications for the heightened adolescent susceptibility to nicotine addiction

DEFF Research Database (Denmark)

Christensen, Mark Holm; Ishibashi, Masaru; Nielsen, Michael Linnemann

2014-01-01

The younger an individual starts smoking, the greater the likelihood that addiction to nicotine will develop, suggesting that neurobiological responses vary across age to the addictive component of cigarettes. Cholinergic neurons of the laterodorsal tegmental nucleus (LDT) are importantly involved...... in the development of addiction, however, the effects of nicotine on LDT neuronal excitability across ontogeny are unknown. Nicotinic effects on LDT cells across different age groups were examined using calcium imaging and whole-cell patch clamping. Within the youngest age group (P7–P15), nicotine induced larger...... intracellular calcium transients and inward currents. Nicotine induced a greater number of excitatory synaptic currents in the youngest animals, whereas larger amplitude inhibitory synaptic events were induced in cells from the oldest animals (P15–P34). Nicotine increased neuronal firing of cholinergic cells...

Subject-specific computational modeling of DBS in the PPTg area

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Laura M. Zitella

2015-07-01

Full Text Available Deep brain stimulation (DBS in the pedunculopontine tegmental nucleus (PPTg has been proposed to alleviate medically intractable gait difficulties associated with Parkinson’s disease. Clinical trials have shown somewhat variable outcomes, stemming in part from surgical targeting variability, modulating fiber pathways implicated in side effects, and a general lack of mechanistic understanding of DBS in this brain region. Subject-specific computational models of DBS are a promising tool to investigate the underlying therapy and side effects. In this study, a parkinsonian rhesus macaque was implanted unilaterally with an 8-contact DBS lead in the PPTg region. Fiber tracts adjacent to PPTg, including the oculomotor nerve, central tegmental tract, and superior cerebellar peduncle, were reconstructed from a combination of pre-implant 7T MRI, post-implant CT, and post-mortem histology. These structures were populated with axon models and coupled with a finite element model simulating the voltage distribution in the surrounding neural tissue during stimulation. This study introduces two empirical approaches to evaluate model parameters. First, incremental monopolar cathodic stimulation (20Hz, 90µs pulse width was evaluated for each electrode, during which a right eyelid flutter was observed at the proximal four contacts (-1.0 to -1.4mA. These current amplitudes followed closely with model predicted activation of the oculomotor nerve when assuming an anisotropic conduction medium. Second, PET imaging was collected OFF-DBS and twice during DBS (two different contacts, which supported the model predicted activation of the central tegmental tract and superior cerebellar peduncle. Together, subject-specific models provide a framework to more precisely predict pathways modulated by DBS.

Evaluating alternative fuel treatment strategies to reduce wildfire losses in a Mediterranean area

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Michele Salis; Maurizio Laconi; Alan A. Ager; Fermin J. Alcasena; Bachisio Arca; Olga Lozano; Ana Fernandes de Oliveira; Donatella Spano

2016-01-01

The goal of this work is to evaluate by a modeling approach the effectiveness of alternative fuel treatment strategies to reduce potential losses from wildfires in Mediterranean areas. We compared strategic fuel treatments located near specific human values vs random locations, and treated 3, 9 and 15% of a 68,000 ha study area located in Sardinia, Italy. The...

Are ranger patrols effective in reducing poaching-related threats within protected areas?

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Moore, Jennnifer F.; Mulindahabi, Felix; Masozera, Michel K.; Nichols, James; Hines, James; Turikunkiko, Ezechiel; Oli, Madan K.

2018-01-01

Poaching is one of the greatest threats to wildlife conservation world-wide. However, the spatial and temporal patterns of poaching activities within protected areas, and the effectiveness of ranger patrols and ranger posts in mitigating these threats, are relatively unknown.We used 10 years (2006–2015) of ranger-based monitoring data and dynamic multi-season occupancy models to quantify poaching-related threats, to examine factors influencing the spatio-temporal dynamics of these threats and to test the efficiency of management actions to combat poaching in Nyungwe National Park (NNP), Rwanda.The probability of occurrence of poaching-related threats was highest at lower elevations (1,801–2,200 m), especially in areas that were close to roads and tourist trails; conversely, occurrence probability was lowest at high elevation sites (2,601–3,000 m), and near the park boundary and ranger posts. The number of ranger patrols substantially increased the probability that poaching-related threats disappear at a site if threats were originally present (i.e. probability of extinction of threats). Without ranger visits, the annual probability of extinction of poaching-related threats was an estimated 7%; this probability would increase to 20% and 57% with 20 and 50 ranger visits per year, respectively.Our results suggest that poaching-related threats can be effectively reduced in NNP by adding ranger posts in areas where they do not currently exist, and by increasing the number of patrols to sites where the probability of poaching activities is high.Synthesis and applications. Our application of dynamic occupancy models to predict the probability of presence of poaching-related threats is novel, and explicitly considers imperfect detection of illegal activities. Based on the modelled relationships, we identify areas that are most vulnerable to poaching, and offer insights regarding how ranger patrols can be optimally deployed to reduce poaching-related threats and

Rhythmic Firing of Pedunculopontine Tegmental Nucleus Neurons in Monkeys during Eye Movement Task.

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Ken-Ichi Okada

Full Text Available The pedunculopontine tegmental nucleus (PPTN has been thought to be involved in the control of behavioral state. Projections to the entire thalamus and reciprocal connections with the basal ganglia nuclei suggest a potential role for the PPTN in the control of various rhythmic behaviors, including waking/sleeping and locomotion. Recently, rhythmic activity in the local field potentials was recorded from the PPTN of patients with Parkinson's disease who were treated with levodopa, suggesting that rhythmic firing is a feature of the functioning PPTN and might change with the behaving conditions even within waking. However, it remains unclear whether and how single PPTN neurons exhibit rhythmic firing patterns during various behaving conditions, including executing conditioned eye movement behaviors, seeking reward, or during resting. We previously recorded from PPTN neurons in healthy monkeys during visually guided saccade tasks and reported task-related changes in firing rate, and in this paper, we reanalyzed these data and focused on their firing patterns. A population of PPTN neurons demonstrated a regular firing pattern in that the coefficient of variation of interspike intervals was lower than what would be expected of theoretical random and irregular spike trains. Furthermore, a group of PPTN neurons exhibited a clear periodic single spike firing that changed with the context of the behavioral task. Many of these neurons exhibited a periodic firing pattern during highly active conditions, either the fixation condition during the saccade task or the free-viewing condition during the intertrial interval. We speculate that these task context-related changes in rhythmic firing of PPTN neurons might regulate the monkey's attentional and vigilance state to perform the task.

Quantifying and Reducing Uncertainty in Correlated Multi-Area Short-Term Load Forecasting

Energy Technology Data Exchange (ETDEWEB)

Sun, Yannan; Hou, Zhangshuan; Meng, Da; Samaan, Nader A.; Makarov, Yuri V.; Huang, Zhenyu

2016-07-17

In this study, we represent and reduce the uncertainties in short-term electric load forecasting by integrating time series analysis tools including ARIMA modeling, sequential Gaussian simulation, and principal component analysis. The approaches are mainly focusing on maintaining the inter-dependency between multiple geographically related areas. These approaches are applied onto cross-correlated load time series as well as their forecast errors. Multiple short-term prediction realizations are then generated from the reduced uncertainty ranges, which are useful for power system risk analyses.

Navy Ordnance Analysis of Business Area Efforts to Streamline Operations and Reduce Costs

National Research Council Canada - National Science Library

1997-01-01

.... The Navy reorganized this business area in 1993 in order to reduce costs and address various deficiencies in ordnance logistics management that were identified during Desert Shield/Desert Storm...

Reducing prefrontal gamma-aminobutyric acid activity induces cognitive, behavioral, and dopaminergic abnormalities that resemble schizophrenia.

Science.gov (United States)

Enomoto, Takeshi; Tse, Maric T; Floresco, Stan B

2011-03-01

Perturbations in gamma-aminobutyric acid (GABA)-related markers have been reported in the prefrontal cortex of schizophrenic patients. However, a preclinical assessment of how suppression of prefrontal cortex GABA activity may reflect behavioral and cognitive pathologies observed in schizophrenia is forthcoming. We assessed the effects of pharmacologic blockade of prefrontal cortex GABA(A) receptors in rats on executive functions and other behaviors related to schizophrenia, as well as neural activity of midbrain dopamine neurons. Blockade of prefrontal cortex GABA(A) receptors with bicuculline (12.5-50 ng) did not affect working memory accuracy but did increase response latencies, resembling speed of processing deficits observed in schizophrenia. Prefrontal cortex GABA(A) blockade did not impede simple discrimination or reversal learning but did impair set-shifting in a manner dependent on when these treatments were given. Reducing GABA activity before the set-shift impaired the ability to acquire a novel strategy, whereas treatment before the initial discrimination increased perseveration during the shift. Latent inhibition was unaffected by bicuculline infusions before the preexposure/conditioning phases, suggesting that reduced prefrontal cortex GABA activity does not impair "learned irrelevance." GABA(A) blockade increased locomotor activity and showed synergic effects with a subthreshold dose of amphetamine. Furthermore, reducing medial prefrontal cortex GABA activity selectively increased phasic burst firing of ventral tegmental area dopamine neurons, without altering the their overall population activity. These results suggest that prefrontal cortex GABA hypofunction may be a key contributing factor to deficits in speed of processing, cognitive flexibility, and enhanced phasic dopamine activity observed in schizophrenia. Copyright © 2011 Society of Biological Psychiatry. Published by Elsevier Inc. All rights reserved.

The Pedunculopontine Tegmental Nucleus as a Motor and Cognitive Interface between the Cerebellum and Basal Ganglia.

Science.gov (United States)

Mori, Fumika; Okada, Ken-Ichi; Nomura, Taishin; Kobayashi, Yasushi

2016-01-01

As an important component of ascending activating systems, brainstem cholinergic neurons in the pedunculopontine tegmental nucleus (PPTg) are involved in the regulation of motor control (locomotion, posture and gaze) and cognitive processes (attention, learning and memory). The PPTg is highly interconnected with several regions of the basal ganglia, and one of its key functions is to regulate and relay activity from the basal ganglia. Together, they have been implicated in the motor control system (such as voluntary movement initiation or inhibition), and modulate aspects of executive function (such as motivation). In addition to its intimate connection with the basal ganglia, projections from the PPTg to the cerebellum have been recently reported to synaptically activate the deep cerebellar nuclei. Classically, the cerebellum and basal ganglia were regarded as forming separated anatomical loops that play a distinct functional role in motor and cognitive behavioral control. Here, we suggest that the PPTg may also act as an interface device between the basal ganglia and cerebellum. As such, part of the therapeutic effect of PPTg deep brain stimulation (DBS) to relieve gait freezing and postural instability in advanced Parkinson's disease (PD) patients might also involve modulation of the cerebellum. We review the anatomical position and role of the PPTg in the pathway of basal ganglia and cerebellum in relation to motor control, cognitive function and PD.

The pedunculopontine tegmental nucleus as a motor and cognitive interface between the cerebellum and basal ganglia

Directory of Open Access Journals (Sweden)

Fumika Mori

2016-11-01

Full Text Available As an important component of ascending activating systems, brainstem cholinergic neurons in the pedunculopontine tegmental nucleus (PPTg are involved in the regulation of motor control (locomotion, posture and gaze and cognitive processes (attention, learning, and memory. The PPTg is highly interconnected with several regions of the basal ganglia, and one of its key functions is to regulate and relay activity from the basal ganglia. Together, they have been implicated in the motor control system (such as voluntary movement initiation or inhibition, and modulate aspects of executive function (such as motivation. In addition to its intimate connection with the basal ganglia, projections from the PPTg to the cerebellum have been recently reported to synaptically activate the deep cerebellar nuclei. Classically, the cerebellum and basal ganglia were regarded as forming separated anatomical loops that play a distinct functional role in motor and cognitive behavioral control. Here, we suggest that the PPTg may also act as an interface device between the basal ganglia and cerebellum. As such, part of the therapeutic effect of PPTg deep brain stimulation to relieve gait freezing and postural instability in advanced Parkinson’s disease patients might also involve modulation of the cerebellum. We review the anatomical position and role of the PPTg in the pathway of basal ganglia and cerebellum in relation to motor control, cognitive function, and Parkinson’s disease.

Addressing equity in interventions to reduce air pollution in urban areas: a systematic review.

Science.gov (United States)

Benmarhnia, Tarik; Rey, Lynda; Cartier, Yuri; Clary, Christelle M; Deguen, Séverine; Brousselle, Astrid

2014-12-01

We did a systematic review to assess quantitative studies investigating the association between interventions aiming to reduce air pollution, health benefits and equity effects. Three databases were searched for studies investigating the association between evaluated interventions aiming to reduce air pollution and heath-related benefits. We designed a two-stage selection process to judge how equity was assessed and we systematically determined if there was a heterogeneous effect of the intervention between subgroups or subareas. Of 145 identified articles, 54 were reviewed in-depth with eight satisfying the inclusion criteria. This systematic review showed that interventions aiming to reduce air pollution in urban areas have a positive impact on air quality and on mortality rates, but the documented effect on equity is less straightforward. Integration of equity in evidence-based public health is a great challenge nowadays. In this review we draw attention to the importance of considering equity in air pollution interventions. We also propose further methodological and theoretical challenges when assessing equity in interventions to reduce air pollution and we present opportunities to develop this research area.

A process to enhance the specific surface area and capacitance of hydrothermally reduced graphene oxide

KAUST Repository

Alazmi, Amira

2016-08-26

The impact of post-synthesis processing in reduced graphene oxide materials for supercapacitor electrodes has been analyzed. A comparative study of vacuum, freeze and critical point drying was carried out for hydrothermally reduced graphene oxide demonstrating that the optimization of the specific surface area and preservation of the porous network are critical to maximize its supercapacitance performance. As described below, using a supercritical fluid as the drying medium, unprecedented values of the specific surface area (364 m2 g−1) and supercapacitance (441 F g−1) for this class of materials have been achieved.

A process to enhance the specific surface area and capacitance of hydrothermally reduced graphene oxide

KAUST Repository

Alazmi, Amira; El Tall, Omar; Rasul, Shahid; Hedhili, Mohamed N.; Patole, Shashikant P.; Da Costa, Pedro M. F. J.

2016-01-01

The impact of post-synthesis processing in reduced graphene oxide materials for supercapacitor electrodes has been analyzed. A comparative study of vacuum, freeze and critical point drying was carried out for hydrothermally reduced graphene oxide demonstrating that the optimization of the specific surface area and preservation of the porous network are critical to maximize its supercapacitance performance. As described below, using a supercritical fluid as the drying medium, unprecedented values of the specific surface area (364 m2 g−1) and supercapacitance (441 F g−1) for this class of materials have been achieved.

The role of urban forest to reduce rain acid in urban industrial areas

Science.gov (United States)

Slamet, B.; Agustiarni, Y.; Hidayati; Basyuni, M.

2018-03-01

Urban forest has many functions mainly on improving the quality of the urban environment. One of the functions is to increase pH and reduce dangerous chemical content. The aim of the research is to find out the role of vegetation density of urban forest around the industrial area in reducing the acid rain. The condition of land cover was classified into four classes which are dense, medium, sparse and open area. The water of the throughfall and stemflow was taken from each type of land cover except in the open area. Parameters measured in this study are water acidity (pH), anion content (SO4 2- and NO3 -), cation content (Ca2+, Mg2+, and NH4 +) and electrical conductivity (EC). The results indicated that urban forest vegetation was able to increase the pH of rain water from 5.42 which is in an open area without vegetation to be 7.13 and 7.32 in dense and moderate vegetation cover by throughfall mechanism, respectively. Rain water acidity also decreased through stemflow mechanism with a pH ranged from 5.92 - 6.43. Urban forest vegetation decreased sulfate content (SO42-) from 528.67 mg/l in open area to 44 - 118 mg/l by throughfall mechanism and ranged from 90 to 366.67 mg/l through stemflow mechanism. Urban forest vegetation significantly decreased the rainwater nitrate content from 27 mg/l to 0.03 - 0.70 mg/l through the mechanism of throughfall and between 1.53 - 8.82 mg/l through the stemflow mechanism. Urban forest vegetation also increased the concentration of cations (NH4+, Ca2+, Mg2+, Na+) compared with open areas. Urban forest vegetation showed increased the electrical conductivity (EC) from 208.12 μmhos/cm to 344.67 - 902.17 μmhos/cm through the through fall mechanism and 937.67 - 1058.70 μmhos/cm through the stemflow mechanism. The study suggested that urban forests play a significant role in reducing rainwater acidity and improving the quality of rainwater that reached the soil surface.

A channel-by-channel method of reducing the errors associated with peak area integration

International Nuclear Information System (INIS)

Luedeke, T.P.; Tripard, G.E.

1996-01-01

A new method of reducing the errors associated with peak area integration has been developed. This method utilizes the signal content of each channel as an estimate of the overall peak area. These individual estimates can then be weighted according to the precision with which each estimate is known, producing an overall area estimate. Experimental measurements were performed on a small peak sitting on a large background, and the results compared to those obtained from a commercial software program. Results showed a marked decrease in the spread of results around the true value (obtained by counting for a long period of time), and a reduction in the statistical uncertainty associated with the peak area. (orig.)

Evaluating the effectiveness of protected areas for maintaining biodiversity, securing habitats, and reducing threats

DEFF Research Database (Denmark)

Geldmann, Jonas

of this thesis has been to evaluate the performance and effectiveness of protected area in securing biodiversity, by evaluating their ability to either improve conservation responses, the state of biodiversity, or alternatively to reduce the human pressures responsible for the loss of biodiversity. The scope......Protected areas are amongst the most important conservation responses to halt the loss of biodiversity and cover more than 12.7% of the terrestrial surface of earth. Likewise, protected areas are an important political instrument and a key component of the Convention for Biological Diversity (CBD......); seeking to protect at least 17% of the terrestrial surface and 10% of the coastal and marine areas by 2020. Protected areas are expected to deliver on many different objectives covering biodiversity, climate change mitigation, local livelihood, and cultural & esthetic values. Within each...

Reduced perfusion in Broca's area in developmental stuttering.

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Desai, Jay; Huo, Yuankai; Wang, Zhishun; Bansal, Ravi; Williams, Steven C R; Lythgoe, David; Zelaya, Fernando O; Peterson, Bradley S

2017-04-01

To study resting cerebral blood flow in children and adults with developmental stuttering. We acquired pulsed arterial spin labeling magnetic resonance imaging data in 26 participants with stuttering and 36 healthy, fluent controls. While covarying for age, sex, and IQ, we compared perfusion values voxel-wise across diagnostic groups and assessed correlations of perfusion with stuttering severity within the stuttering group and with measures of motor speed in both groups. We detected lower regional Cerebral Blood Flow (rCBF) at rest in the stuttering group compared with healthy controls in Broca's area bilaterally and the superior frontal gyrus. rCBF values in Broca's area bilaterally correlated inversely with the severity of stuttering and extended posteriorly into other portions of the language loop. We also found increased rCBF in cerebellar nuclei and parietal cortex in the stuttering group compared with healthy controls. Findings were unchanged in child-only analyses and when excluding participants with comorbid illnesses or those taking medication. rCBF is reduced in Broca's region in persons who stutter. More severe stuttering is associated with even greater reductions in rCBF to Broca's region, additive to the underlying putative trait reduction in rCBF relative to control values. Moreover, a greater abnormality in rCBF in the posterior language loop is associated with more severe symptoms, suggesting that a common pathophysiology throughout the language loop likely contributes to stuttering severity. Hum Brain Mapp 38:1865-1874, 2017. © 2017 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

Metabolic mapping of the effects of the antidepressant fluoxetine on the brains of congenitally helpless rats.

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Shumake, Jason; Colorado, Rene A; Barrett, Douglas W; Gonzalez-Lima, F

2010-07-09

Antidepressants require adaptive brain changes before efficacy is achieved, and they may impact the affectively disordered brain differently than the normal brain. We previously demonstrated metabolic disturbances in limbic and cortical regions of the congenitally helpless rat, a model of susceptibility to affective disorder, and we wished to test whether administration of fluoxetine would normalize these metabolic differences. Fluoxetine was chosen because it has become a first-line drug for the treatment of affective disorders. We hypothesized that fluoxetine antidepressant effects may be mediated by decreasing metabolism in the habenula and increasing metabolism in the ventral tegmental area. We measured the effects of fluoxetine on forced swim behavior and regional brain cytochrome oxidase activity in congenitally helpless rats treated for 2 weeks with fluoxetine (5mg/kg, i.p., daily). Fluoxetine reduced immobility in the forced swim test as anticipated, but congenitally helpless rats responded in an atypical manner, i.e., increasing climbing without affecting swimming. As hypothesized, fluoxetine reduced metabolism in the habenula and increased metabolism in the ventral tegmental area. In addition, fluoxetine reduced the metabolism of the hippocampal dentate gyrus and dorsomedial prefrontal cortex. This study provided the first detailed mapping of the regional brain effects of an antidepressant drug in congenitally helpless rats. All of the effects were consistent with previous studies that have metabolically mapped the effects of serotonergic antidepressants in the normal rat brain, and were in the predicted direction of metabolic normalization of the congenitally helpless rat for all affected brain regions except the prefrontal cortex. Copyright (c) 2010 Elsevier B.V. All rights reserved.

Chronic self-administration of alcohol results in elevated ΔFosB: comparison of hybrid mice with distinct drinking patterns

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Ozburn Angela R

2012-10-01

Full Text Available Abstract Background The inability to reduce or regulate alcohol intake is a hallmark symptom for alcohol use disorders. Research on novel behavioral and genetic models of experience-induced changes in drinking will further our knowledge on alcohol use disorders. Distinct alcohol self-administration behaviors were previously observed when comparing two F1 hybrid strains of mice: C57BL/6J x NZB/B1NJ (BxN show reduced alcohol preference after experience with high concentrations of alcohol and periods of abstinence while C57BL/6J x FVB/NJ (BxF show sustained alcohol preference. These phenotypes are interesting because these hybrids demonstrate the occurrence of genetic additivity (BxN and overdominance (BxF in ethanol intake in an experience dependent manner. Specifically, BxF exhibit sustained alcohol preference and BxN exhibit reduced alcohol preference after experience with high ethanol concentrations; however, experience with low ethanol concentrations produce sustained alcohol preference for both hybrids. In the present study, we tested the hypothesis that these phenotypes are represented by differential production of the inducible transcription factor, ΔFosB, in reward, aversion, and stress related brain regions. Results Changes in neuronal plasticity (as measured by ΔFosB levels were experience dependent, as well as brain region and genotype specific, further supporting that neuronal circuitry underlies motivational aspects of ethanol consumption. BxN mice exhibiting reduced alcohol preference had lower ΔFosB levels in the Edinger-Westphal nucleus than mice exhibiting sustained alcohol preference, and increased ΔFosB levels in central medial amygdala as compared with control mice. BxN mice showing sustained alcohol preference exhibited higher ΔFosB levels in the ventral tegmental area, Edinger-Westphal nucleus, and amygdala (central and lateral divisions. Moreover, in BxN mice ΔFosB levels in the Edinger-Westphal nucleus and ventral

Reduced isotope uptake restricted to the motor area in patients with amyotrophic lateral sclerosis

International Nuclear Information System (INIS)

Abe, K.; Yorifuji, S.; Nishikawa, Y.

1993-01-01

To study degeneration in the central nervous system in amyotrophic lateral sclerosis (ALS), we studied four patients using single photon emission tomography (SPECT) and magnetic resonance imaging (MRI). MRI demonstrated high intensity along the pyramidal tract on T2-weighted images in two. SPECT demonstrated reduced isotope uptake restricted to the motor area. While the cause of degeneration of the cortical neurons in the motor area is unknown, SPECT is useful for detecting the degeneration in patients with ALS. (orig.)

Tropical protected areas reduced deforestation carbon emissions by one third from 2000-2012.

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Bebber, Daniel P; Butt, Nathalie

2017-10-25

Tropical deforestation is responsible for around one tenth of total anthropogenic carbon emissions, and tropical protected areas (PAs) that reduce deforestation can therefore play an important role in mitigating climate change and protecting biodiversity and ecosystem services. While the effectiveness of PAs in reducing deforestation has been estimated, the impact on global carbon emissions remains unquantified. Here we show that tropical PAs overall reduced deforestation carbon emissions by 4.88 Pg, or around 29%, between 2000 and 2012, when compared to expected rates of deforestation controlling for spatial variation in deforestation pressure. The largest contribution was from the tropical Americas (368.8 GgC y -1 ), followed by Asia (25.0 GgC y -1 ) and Africa (12.7 GgC y -1 ). Variation in PA effectiveness is largely driven by local factors affecting individual PAs, rather than designations assigned by governments.

Acute food deprivation reverses morphine-induced locomotion deficits in M5 muscarinic receptor knockout mice.

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Steidl, Stephan; Lee, Esther; Wasserman, David; Yeomans, John S

2013-09-01

Lesions of the pedunculopontine tegmental nucleus (PPT), one of two sources of cholinergic input to the ventral tegmental area (VTA), block conditioned place preference (CPP) for morphine in drug-naïve rats. M5 muscarinic cholinergic receptors, expressed by midbrain dopamine neurons, are critical for the ability of morphine to increase nucleus accumbens dopamine levels and locomotion, and for morphine CPP. This suggests that M5-mediated PPT cholinergic inputs to VTA dopamine neurons critically contribute to morphine-induced dopamine activation, reward and locomotion. In the current study we tested whether food deprivation, which reduces PPT contribution to morphine CPP in rats, could also reduce M5 contributions to morphine-induced locomotion in mice. Acute 18-h food deprivation reversed the phenotypic differences usually seen between non-deprived wild-type and M5 knockout mice. That is, food deprivation increased morphine-induced locomotion in M5 knockout mice but reduced morphine-induced locomotion in wild-type mice. Food deprivation increased saline-induced locomotion equally in wild-type and M5 knockout mice. Based on these findings, we suggest that food deprivation reduces the contribution of M5-mediated PPT cholinergic inputs to the VTA in morphine-induced locomotion and increases the contribution of a PPT-independent pathway. The contributions of cholinergic, dopaminergic and GABAergic neurons to the effects of acute food deprivation are discussed. Copyright © 2013 Elsevier B.V. All rights reserved.

Reduced Perfusion in Broca’s Area in Developmental Stuttering

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Desai, Jay; Huo, Yuankai; Wang, Zhishun; Bansal, Ravi; Williams, Steven C. R.; Lythgoe, David; Zelaya, Fernando O.; Peterson, Bradley S.

2016-01-01

Objective To study resting cerebral blood flow in children and adults with developmental stuttering. Methods We acquired pulsed arterial spin labeling magnetic resonance imaging data in 26 participants with stuttering and 36 healthy, fluent controls. While covarying for age, sex, and IQ, we compared perfusion values voxel-wise across diagnostic groups and assessed correlations of perfusion with stuttering severity within the stuttering group and with measures of motor speed in both groups. Results We detected lower regional Cerebral Blood Flow (rCBF) at rest in the stuttering group compared to healthy controls in Broca’s area bilaterally and the superior frontal gyrus. rCBF values in Broca’s area bilaterally correlated inversely with the severity of stuttering and extended posteriorly into other portions of the language loop. We also found increased rCBF in cerebellar nuclei and parietal cortex in the stuttering group compared to healthy controls. Findings were unchanged in child-only analyses and when excluding participants with comorbid illnesses or those taking medication. Conclusions rCBF is reduced in Broca’s region in persons who stutter. More severe stuttering is associated with even greater reductions in rCBF to Broca’s region, additive to the underlying putative trait reduction in rCBF relative to control values. Moreover, a greater abnormality in rCBF in the posterior language loop is associated with more severe symptoms, suggesting that a common pathophysiology throughout the language loop likely contributes to stuttering severity. PMID:28035724

[Intervention to reduce the impact of light and noise on sleep in an emergency department observation area].

Science.gov (United States)

Villamor Ordozgoiti, Alberto; Priu Parra, Inmaculada; España Salvador, María Carmen; Torres Valdés, Constancia; Bas Ciutad, María Pilar; Ponce Quílez, María Rosa

2017-02-01

To study quality of patient rest before and after an intervention to reduce nighttime light and noise in the emergency department observation area of an urban hospital. Quasi-experimental study in 2 groups before and after the intervention in the observation area of the Hospital Clínic de Barcelona. We administered a questionnaire about the quality of nighttime rest to assess the effect of light and noise on sleep. Light and noise were reduced by means of structural changes to the environment and through the introduction of protocols to modify how care plans were carried out at night. Fifty nurses participated in the pre-intervention study and 371 in the post-intervention study. Seventy-two percent and 91.37% of the patients reported resting well before and after the intervention, respectively (P< .001). Factors like pain, nursing care, or daytime naps do not affect sleep quality. Nighttime rest in emergency department observation areas is affected by ambient light and noise more than by other variables. Reducing light and noise at night can measurably improve patients' rest.

Human aging reduces the neurobehavioral influence of motivation on episodic memory.

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Geddes, Maiya R; Mattfeld, Aaron T; Angeles, Carlo de Los; Keshavan, Anisha; Gabrieli, John D E

2018-05-01

The neural circuitry mediating the influence of motivation on long-term declarative or episodic memory formation is delineated in young adults, but its status is unknown in healthy aging. We examined the effect of reward and punishment anticipation on intentional declarative memory formation for words using an event-related functional magnetic resonance imaging (fMRI) monetary incentive encoding task in twenty-one younger and nineteen older adults. At 24-hour memory retrieval testing, younger adults were significantly more likely to remember words associated with motivational cues than neutral cues. Motivational enhancement of memory in younger adults occurred only for recollection ("remember" responses) and not for familiarity ("familiar" responses). Older adults had overall diminished memory and did not show memory gains in association with motivational cues. Memory encoding associated with monetary rewards or punishments activated motivational (substantia nigra/ventral tegmental area) and memory-related (hippocampus) brain regions in younger, but not older, adults during the target word periods. In contrast, older and younger adults showed similar activation of these brain regions during the anticipatory motivational cue interval. In a separate monetary incentive delay task that did not require learning, we found evidence for relatively preserved striatal reward anticipation in older adults. This supports a potential dissociation between incidental and intentional motivational processes in healthy aging. The finding that motivation to obtain rewards and avoid punishments had reduced behavioral and neural influence on intentional episodic memory formation in older compared to younger adults is relevant to life-span theories of cognitive aging including the dopaminergic vulnerability hypothesis. Copyright © 2017 The Authors. Published by Elsevier Inc. All rights reserved.

Reduced structural connectivity between sensorimotor and language areas in rolandic epilepsy.

Directory of Open Access Journals (Sweden)

René M H Besseling

Full Text Available Rolandic epilepsy (RE is a childhood epilepsy with centrotemporal (rolandic spikes, that is increasingly associated with language impairment. In this study, we tested for a white matter (connectivity correlate, employing diffusion weighted MRI and language testing.Twenty-three children with RE and 23 matched controls (age: 8-14 years underwent structural (T1-weighted and diffusion-weighted MRI (b = 1200 s/mm(2, 66 gradient directions at 3T, as well as neuropsychological language testing. Combining tractography and a cortical segmentation derived from the T1-scan, the rolandic tract were reconstructed (pre- and postcentral gyri, and tract fractional anisotropy (FA values were compared between patients and controls. Aberrant tracts were tested for correlations with language performance.Several reductions of tract FA were found in patients compared to controls, mostly in the left hemisphere; the most significant effects involved the left inferior frontal (p = 0.005 and supramarginal (p = 0.004 gyrus. In the patient group, lower tract FA values were correlated with lower language performance, among others for the connection between the left postcentral and inferior frontal gyrus (p = 0.043, R = 0.43.In RE, structural connectivity is reduced for several connections involving the rolandic regions, from which the epileptiform activity originates. Most of these aberrant tracts involve the left (typically language mediating hemisphere, notably the pars opercularis of the inferior frontal gyrus (Broca's area and the supramarginal gyrus (Wernicke's area. For the former, reduced language performance for lower tract FA was found in the patients. These findings provide a first microstructural white matter correlate for language impairment in RE.

A neurocomputational account of reward and novelty processing and effects of psychostimulants in attention deficit hyperactivity disorder.

Science.gov (United States)

Sethi, Arjun; Voon, Valerie; Critchley, Hugo D; Cercignani, Mara; Harrison, Neil A

2018-05-01

Computational models of reinforcement learning have helped dissect discrete components of reward-related function and characterize neurocognitive deficits in psychiatric illnesses. Stimulus novelty biases decision-making, even when unrelated to choice outcome, acting as if possessing intrinsic reward value to guide decisions toward uncertain options. Heightened novelty seeking is characteristic of attention deficit hyperactivity disorder, yet how this influences reward-related decision-making is computationally encoded, or is altered by stimulant medication, is currently uncertain. Here we used an established reinforcement-learning task to model effects of novelty on reward-related behaviour during functional MRI in 30 adults with attention deficit hyperactivity disorder and 30 age-, sex- and IQ-matched control subjects. Each participant was tested on two separate occasions, once ON and once OFF stimulant medication. OFF medication, patients with attention deficit hyperactivity disorder showed significantly impaired task performance (P = 0.027), and greater selection of novel options (P = 0.004). Moreover, persistence in selecting novel options predicted impaired task performance (P = 0.025). These behavioural deficits were accompanied by a significantly lower learning rate (P = 0.011) and heightened novelty signalling within the substantia nigra/ventral tegmental area (family-wise error corrected P attention deficit hyperactivity disorder participants' overall task performance (P = 0.011), increased reward-learning rates (P = 0.046) and enhanced their ability to differentiate optimal from non-optimal novel choices (P = 0.032). It also reduced substantia nigra/ventral tegmental area responses to novelty. Preliminary cross-sectional evidence additionally suggested an association between long-term stimulant treatment and a reduction in the rewarding value of novelty. These data suggest that aberrant substantia nigra/ventral tegmental area novelty processing plays an

Activation of the GLP-1 receptors in the nucleus of the solitary tract reduces food reward behavior and targets the mesolimbic system.

Directory of Open Access Journals (Sweden)

Jennifer E Richard

Full Text Available The gut/brain peptide, glucagon like peptide 1 (GLP-1, suppresses food intake by acting on receptors located in key energy balance regulating CNS areas, the hypothalamus or the hindbrain. Moreover, GLP-1 can reduce reward derived from food and motivation to obtain food by acting on its mesolimbic receptors. Together these data suggest a neuroanatomical segregation between homeostatic and reward effects of GLP-1. Here we aim to challenge this view and hypothesize that GLP-1 can regulate food reward behavior by acting directly on the hindbrain, the nucleus of the solitary tract (NTS, GLP-1 receptors (GLP-1R. Using two models of food reward, sucrose progressive ratio operant conditioning and conditioned place preference for food in rats, we show that intra-NTS microinjections of GLP-1 or Exendin-4, a stable analogue of GLP-1, inhibit food reward behavior. When the rats were given a choice between palatable food and chow, intra-NTS Exendin-4 treatment preferentially reduced intake of palatable food but not chow. However, chow intake and body weight were reduced by the NTS GLP-1R activation if chow was offered alone. The NTS GLP-1 activation did not alter general locomotor activity and did not induce nausea, measured by PICA. We further show that GLP-1 fibers are in close apposition to the NTS noradrenergic neurons, which were previously shown to provide a monosynaptic connection between the NTS and the mesolimbic system. Central GLP-1R activation also increased NTS expression of dopamine-β-hydroxylase, a key enzyme in noradrenaline synthesis, indicating a biological link between these two systems. Moreover, NTS GLP-1R activation altered the expression of dopamine-related genes in the ventral tegmental area. These data reveal a food reward-suppressing role of the NTS GLP-1R and indicate that the neurobiological targets underlying food reward control are not limited to the mesolimbic system, instead they are distributed throughout the CNS.

Activation of the GLP-1 receptors in the nucleus of the solitary tract reduces food reward behavior and targets the mesolimbic system.

Science.gov (United States)

Richard, Jennifer E; Anderberg, Rozita H; Göteson, Andreas; Gribble, Fiona M; Reimann, Frank; Skibicka, Karolina P

2015-01-01

The gut/brain peptide, glucagon like peptide 1 (GLP-1), suppresses food intake by acting on receptors located in key energy balance regulating CNS areas, the hypothalamus or the hindbrain. Moreover, GLP-1 can reduce reward derived from food and motivation to obtain food by acting on its mesolimbic receptors. Together these data suggest a neuroanatomical segregation between homeostatic and reward effects of GLP-1. Here we aim to challenge this view and hypothesize that GLP-1 can regulate food reward behavior by acting directly on the hindbrain, the nucleus of the solitary tract (NTS), GLP-1 receptors (GLP-1R). Using two models of food reward, sucrose progressive ratio operant conditioning and conditioned place preference for food in rats, we show that intra-NTS microinjections of GLP-1 or Exendin-4, a stable analogue of GLP-1, inhibit food reward behavior. When the rats were given a choice between palatable food and chow, intra-NTS Exendin-4 treatment preferentially reduced intake of palatable food but not chow. However, chow intake and body weight were reduced by the NTS GLP-1R activation if chow was offered alone. The NTS GLP-1 activation did not alter general locomotor activity and did not induce nausea, measured by PICA. We further show that GLP-1 fibers are in close apposition to the NTS noradrenergic neurons, which were previously shown to provide a monosynaptic connection between the NTS and the mesolimbic system. Central GLP-1R activation also increased NTS expression of dopamine-β-hydroxylase, a key enzyme in noradrenaline synthesis, indicating a biological link between these two systems. Moreover, NTS GLP-1R activation altered the expression of dopamine-related genes in the ventral tegmental area. These data reveal a food reward-suppressing role of the NTS GLP-1R and indicate that the neurobiological targets underlying food reward control are not limited to the mesolimbic system, instead they are distributed throughout the CNS.

Role for the Rostromedial Tegmental Nucleus in Signaling the Aversive Properties of Alcohol.

Science.gov (United States)

Glover, Elizabeth J; McDougle, Molly J; Siegel, Griffin S; Jhou, Thomas C; Chandler, L Judson

2016-08-01

While the rewarding effects of alcohol contribute significantly to its addictive potential, it is becoming increasingly appreciated that alcohol's aversive properties also play an important role in the propensity to drink. Despite this, the neurobiological mechanism for alcohol's aversive actions is not well understood. The rostromedial tegmental nucleus (RMTg) was recently characterized for its involvement in aversive signaling and has been shown to encode the aversive properties of cocaine, yet its involvement in alcohol's aversive actions have not been elucidated. Adult male and female Long-Evans rats underwent conditioned taste aversion (CTA) procedures where exposure to a novel saccharin solution was paired with intraperitoneal administration of saline, lithium chloride (LiCl), or ethanol (EtOH). Control rats underwent the same paradigm except that drug and saccharin exposure were explicitly unpaired. Saccharin consumption was measured on test day in the absence of drug administration, and rats were sacrificed 90 to 105 minutes following access to saccharin. Brains were subsequently harvested and processed for cFos immunohistochemistry. The number of cFos-labeled neurons was counted in the RMTg and the lateral habenula (LHb)-a region that sends prominent glutamatergic input to the RMTg. In rats that received paired drug and saccharin exposure, EtOH and LiCl induced significant CTA compared to saline to a similar degree in males and females. Both EtOH- and LiCl-induced CTA significantly enhanced cFos expression in the RMTg and LHb but not the hippocampus. Similar to behavioral measures, no significant effect of sex on CTA-induced cFos expression was observed. cFos expression in both the RMTg and LHb was significantly correlated with CTA magnitude with greater cFos being associated with more pronounced CTA. In addition, cFos expression in the RMTg was positively correlated with LHb cFos. These data suggest that the RMTg and LHb are involved in the expression of

http://www.bio.uaic.ro/publicatii/anale_biochimie/data/archive/papers/2007/2/2007_Anale_GBM_VIII_f2_l23.pdf

Directory of Open Access Journals (Sweden)

Lucian Hritcu

2007-12-01

Full Text Available The effects of lesioning the ventral tegmental area or substantia nigra pars reticulata by means of bilateral microinjections of two doses of kainic acid (50 ng/250 nl and 100 ng/500 nl were investigated to clarify the role of the mesotelencephalic dopamine system in learning and memory processes. Our findings suggest that ventral tegmental area and substantia nigra dopaminergic neurons play an important role in retention of both short-term memory, tested in the Ymaze task and long-term memory evaluated with the multi-trial passive avoidance test, without affecting memory acquisition. As compared to short-term memory, long-term memory is more susceptible to the decreased dopamine level in nervous structures involved in processing and storage of information

Prenatal nicotine is associated with reduced AMPA and NMDA receptor-mediated rises in calcium within the laterodorsal tegmentum: a pontine nucleus involved in addiction processes

DEFF Research Database (Denmark)

Mc Nair, Laura Kristine Frendrup; Kohlmeier, Kristi Anne

2015-01-01

excitatory neurotransmitter within the laterodorsal tegmental nucleus (LDT), which is a brainstem region importantly involved in responding to motivational stimuli and critical in development of drug addiction-associated behaviours, however, it is unknown whether PNE alters glutamate signalling within...

A new aspect of chronic pain as a lifestyle-related disease

Directory of Open Access Journals (Sweden)

Emiko Senba

2017-01-01

Full Text Available Physical exercise has been established as a low-cost, safe, and effective way to manage chronic intractable pain. We investigated the underlying mechanisms of exercise-induced hypoalgesia (EIH using a mouse model of neuropathic pain (NPP. Epigenetic changes in activated microglia and maintained GABA synthesis in the spinal dorsal horn may contribute to EIH. Voluntary exercise (VE, a strong reward for animals, also induced EIH, which may be due in part to the activation of dopamine (DA neurons in the ventral tegmental area (VTA. VE increases the expression of pCREB in dopaminergic neurons in the VTA, which would enhance dopamine production, and thereby contributes to the activation of the mesolimbic reward system in NPP model mice. We demonstrated that neurons in the laterodorsal tegmental and pedunculopontine tegmental nuclei, a major input source of rewarding stimuli to the VTA, were activated by exercise.Chronic pain is at least partly attributed to sedentary and inactive lifestyle as indicated by the Fear-avoidance model. Therefore, chronic pain could be recognized as a lifestyle-related disease. Physical activity/inactivity may be determined by genetic/epigenetic and neural factors encoded in our brain. The hypothalamus and reward system is closely related in the axis of food intake, energy metabolism and physical activity. Understanding the interactions between the mesolimbic DA system and the hypothalamus that sense and regulate energy balance is thus of significant importance. For example, proopiomelanocortin neurons and melanocortin 4 receptors may play a role in connecting these two systems. Therefore, in a certain sense, chronic pain and obesity may share common behavioral and neural pathology, i.e. physical inactivity, as a result of inactivation of the mesolimbic DA system. Exercise and increasing physical activity in daily life may be important in treating and preventing chronic pain, a life-style related disease. Keywords: Exercise

Limbic connections with the ventral tegmental area in the nonhuman primate

OpenAIRE

Hernández Mombiela, Diana

2016-01-01

Las conductas adictivas consisten en la perdida de libertad frente a una variedad de estímulos en los que el individuo ha perdido la capacidad de controlar sus propios impulsos. Gran cantidad de trabajos experimentales se ha hecho para descubrir los mecanismos neurobiológicos subyacentes en la adicción, especialmente en los roedores. Conductas adictivas observadas en modelos experimentales muestran déficits en las funciones cognitivas que dependen del lóbulo frontal, en particular en la activ...

Neuroanatomy of melanocortin-4 receptor pathway in the lateral hypothalamic area.

Science.gov (United States)

Cui, Huxing; Sohn, Jong-Woo; Gautron, Laurent; Funahashi, Hisayuki; Williams, Kevin W; Elmquist, Joel K; Lutter, Michael

2012-12-15

The central melanocortin system regulates body energy homeostasis including the melanocortin-4 receptor (MC4R). The lateral hypothalamic area (LHA) receives dense melanocortinergic inputs from the arcuate nucleus of the hypothalamus and regulates multiple processes including food intake, reward behaviors, and autonomic function. By using a mouse line in which green fluorescent protein (GFP) is expressed under control of the MC4R gene promoter, we systemically investigated MC4R signaling in the LHA by combining double immunohistochemistry, electrophysiology, and retrograde tracing techniques. We found that LHA MC4R-GFP neurons coexpress neurotensin as well as the leptin receptor but do not coexpress other peptide neurotransmitters found in the LHA including orexin, melanin-concentrating hormone, and nesfatin-1. Furthermore, electrophysiological recording demonstrated that leptin, but not the MC4R agonist melanotan II, hyperpolarizes the majority of LHA MC4R-GFP neurons in an ATP- sensitive potassium channel-dependent manner. Retrograde tracing revealed that LHA MC4R-GFP neurons do not project to the ventral tegmental area, dorsal raphe nucleus, nucleus accumbens, and spinal cord, and only limited number of neurons project to the nucleus of the solitary tract and parabrachial nucleus. Our findings provide new insights into MC4R signaling in the LHA and its potential implications in homeostatic regulation of body energy balance. Copyright © 2012 Wiley Periodicals, Inc.

Reducing microscopy-based malaria misdiagnosis in a low-resource area of Tanzania.

Science.gov (United States)

Allen, Lisa K; Hatfield, Jennifer M; Manyama, Mange

2013-01-01

Misdiagnosis of malaria is a major problem in Africa leading not only to incorrect individual level treatment, but potentially the acceleration of the spread of drug resistance in low-transmission areas. In this paper we report on the outcomes of a simple intervention that utilized a social entrepreneurship approach (SEA) to reduce misdiagnosis associated with hospital-based microscopy of malaria in a low-transmission area of rural Tanzania. A pre-post assessment was conducted on patients presenting to the hospital outpatient department with malaria and non-malaria like symptoms in January 2009 (pre-intervention) and June 2009 (post-intervention). All participants were asked a health seeking behavior questionnaire and blood samples were taken for local and quality control microscopy. Multivariate logistic regression was conducted to determine magnitude of misdiagnosis with local microscopy pre- versus- post intervention. Local microscopy pre-intervention specificity was 29.5% (95% CI = 21.6% - 38.4%) whereas the post intervention specificity was 68.6% (95% CI = 60.2% - 76.2%). Both pre and post intervention sensitivity were difficult to determine due to an unexpected low number of true positive cases. The proportion of participants misdiagnosed pre-intervention was 70.2% (95%CI = 61.3%-78.0%) as compared to 30.6% (95%CI = 23.2%-38.8%) post-intervention. This resulted in a 39.6% reduction in misdiagnosis of malaria at the local hospital. The magnitude of misdiagnosis for the pre-intervention participants was 5.3 (95%CI = 3.1-9.3) that of the post-intervention participants. In conclusion, this study provides evidence that a simple intervention can meaningfully reduce the magnitude of microscopy-based misdiagnosis of malaria for those individuals seeking treatment for uncomplicated malaria. We anticipate that this intervention will facilitate a valuable and sustainable change in malaria diagnosis at the local hospital.

The Brainstem Pathologies of Parkinson's Disease and Dementia with Lewy Bodies

NARCIS (Netherlands)

Seidel, Kay; Mahlke, Josefine; Siswanto, Sonny; Krueger, Reijko; Heinsen, Helmut; Auburger, Georg; Bouzrou, Mohamed; Grinberg, Lea T.; Wicht, Helmut; Korf, Horst-Werner; den Dunnen, Wilfred; Rueb, Udo

Parkinson's disease (PD) and dementia with Lewy bodies (DLB) are among the human synucleinopathies, which show alpha-synuclein immunoreactive neuronal and/or glial aggregations and progressive neuronal loss in selected brain regions (eg, substantia nigra, ventral tegmental area, pedunculopontine

Estimating the health and economic benefits associated with reducing air pollution in the Barcelona metropolitan area (Spain).

Science.gov (United States)

Pérez, Laura; Sunyer, Jordi; Künzli, Nino

2009-01-01

To estimate the health and economic benefits that would result from two scenarios of improved air quality in 57 municipalities of the metropolitan area of Barcelona. We used attributable fractions and life tables to quantify the benefits for selected health outcomes, based on published concentration-response functions and economic unit values. The mean weighted concentration of PM(10) for the study population was estimated through concentration surface maps developed by the local government. The annual mean health benefits of reducing the mean PM(10) exposure estimated for the population in the study area (50microg/m(3)) to the annual mean value recommended by the World Health Organization (20microg/m(3)) were estimated to be 3,500 fewer deaths (representing an average increase in life expectancy of 14 months), 1,800 fewer hospitalizations for cardio-respiratory diseases, 5,100 fewer cases of chronic bronchitis among adults, 31,100 fewer cases of acute bronchitis among children, and 54,000 fewer asthma attacks among children and adults. The mean total monetary benefits were estimated to be 6,400 million euros per year. Reducing PM(10) to comply with the current European Union regulatory annual mean level (40microg/m(3)) would yield approximately one third of these benefits. This study shows that reducing air pollution in the metropolitan area of Barcelona would result in substantial health and economic benefits. The benefits are probably underestimated due to the assumptions made in this study. Assessment of the health impact of local air pollution is a useful tool in public health.

Voluntary nicotine consumption triggers in vivo potentiation of cortical excitatory drives to midbrain dopaminergic neurons

NARCIS (Netherlands)

Caillé, S.; Guillem, K.; Cador, M.; Manzoni, O.; Georges, F.

2009-01-01

Active response to either natural or pharmacological reward causes synaptic modifications to excitatory synapses on dopamine (DA) neurons of the ventral tegmental area (VTA). Here, we examine these modifications using nicotine, the main addictive component of tobacco, which is a potent regulator of

Analysis, Evaluation and Measures to Reduce Environmental Risk within Watershed Areas of the Eastern Zauralye District Lakes

Science.gov (United States)

Rasskasova, N. S.; Bobylev, A. V.; Malaev, A. V.

2017-11-01

The authors have performed an analysis for the use of watershed areas of the lakes of the Eastern Zauralye district (the territory to the east of Ural) for national economic purposes. The analysis gave a possibility to assess the impact of watersheds depending on the applied technologies on the dump of various runoff into the reservoir waters. The watershed areas of all lakes have been found to be actively used as pastures, farmland and recreational resources. Some of the main sources of solid and liquid industrial waste are cattle farms and agricultural land using outdated equipment and technologies. The study of 26 km of the watershed line areas showed that pollutants (household garbage, fuels and lubricants) and organic substances (phosphorus and nitrogen) got into the waters of the reservoirs. The maximum runoff of solid and liquid waste into the waters of the lakes happens in summer which leads to increased concentrations of organic substances, an increase in productivity of alga and higher aquatic flora determining the degree of eutrophication and trophy in the reservoirs. The average annual trophic status of TSI lakes of the Eastern Zauralye district is 56 which corresponds to the typical phase of eutrophy. The reduced transparency of lakes is also the evidence of an increase in biological productivity of reservoirs, their eutrophication and, as a result, the water quality deterioration. The intensive eutrophication of reservoirs, in its turn, most significantly affects the concentration of the ammonium form of nitrogen, total phosphorus and total nitrogen, increase in pH and deterioration of oxygen condition. The authors have developed various activities to reduce a technogenic risk in the watershed areas of the lakes in the Eastern Zauralye district which can be applied to other areas using the analogy method.

Autoradiographic localization of delta opioid receptors within the mesocorticolimbic dopamine system using radioiodinated (2-D-penicillamine, 5-D-penicillamine)enkephalin ( sup 125 I-DPDPE)

Energy Technology Data Exchange (ETDEWEB)

Dilts, R.P.; Kalivas, P.W. (Washington State Univ., Pullman (USA))

1990-01-01

The enkephalin analog (2-D-penicillamine, 5-D-penicillamine)enkephalin was radioiodinated (125I-DPDPE) and shown to retain a pharmacological selectivity characteristic of the delta opioid receptor in in vitro binding studies. The distributions of 125I-DPDPE binding, using in vitro autoradiographic techniques, were similar to those previously reported for the delta opioid receptor. The nucleus accumbens, striatum, and medial prefrontal cortex contain dense gradients of 125I-DPDPE binding in regions known to receive dopaminergic afferents emanating from the mesencephalic tegmentum. Selective chemical lesions of the ventral tegmental area and substantia nigra were employed to deduce the location of the 125I-DPDPE binding within particular regions of the mesocorticolimbic dopamine system. Unilateral lesions of dopamine perikarya (A9 and A10) within the ventral tegmental area and substantia nigra produced by mesencephalic injection of 6-hydroxydopamine resulted in significant (20-30%) increases in 125I-DPDPE binding contralateral to the lesion within the striatum and nucleus accumbens. Lesions of the perikarya (dopaminergic and nondopaminergic) of the ventral tegmental area, induced by quinolinic acid injections, caused increases of less magnitude within these same nuclei. No significant alterations in 125I-DPDPE binding were observed within the mesencephalon as a result of either treatment. The specificity of the lesions was confirmed by immunocytochemistry for tyrosine hydroxylase. These results suggest that the enkephalins and opioid agonists acting through delta opioid receptors do not directly modulate dopaminergic afferents but do regulate postsynaptic targets of the mesocorticolimbic dopamine system.

Reduced binding of Pittsburgh Compound-B in areas of white matter hyperintensities

Directory of Open Access Journals (Sweden)

A.E. Goodheart

2015-01-01

Full Text Available The amyloid imaging agent, Pittsburgh Compound-B, binds with high affinity to β-amyloid (Aβ in the brain, and it is well established that PiB also shows non-specific retention in white matter (WM. However, little is known about retention of PiB in areas of white matter hyperintensities (WMH, abnormalities commonly seen in older adults. Further, it is hypothesized that WMH are related to both cognitive dysfunction and Aβ deposition. The goal of the present study was to explore PiB retention in both normal-appearing WM (NAWM and WMH in a group of elderly, cognitively normal individuals. In a group of cognitively normal elderly (n = 64; 86.5 ± 2.6 years two analyses were applied: (1 ROIs were placed over periventricular areas in which WMH caps are commonly seen on all subjects, regardless of WMH burden or size. (2 Subject-specific maps of NAWM and WMH were co-registered with the PiB-PET images and mean SUVR values were calculated in these NAWM and WMH maps. PiB retention was significantly reduced in the ROIs of subjects with high WMH compared to subjects with low WMH. Additionally, in subjects with high WMH, there was significantly lower PiB retention in subject-specific maps of WMH compared to NAWM, which was not observed in subjects with low WMH, likely because of the small size of WMH maps in this group. These data suggest that WM in areas of WMH binds PiB less effectively than does normal WM. Further exploration of this phenomenon may lead to insights about the molecular basis of the non-specific retention of amyloid tracers in white matter.

The area postrema (AP) and the parabrachial nucleus (PBN) are important sites for salmon calcitonin (sCT) to decrease evoked phasic dopamine release in the nucleus accumbens (NAc).

Science.gov (United States)

Whiting, Lynda; McCutcheon, James E; Boyle, Christina N; Roitman, Mitchell F; Lutz, Thomas A

2017-07-01

The pancreatic hormone amylin and its agonist salmon calcitonin (sCT) act via the area postrema (AP) and the lateral parabrachial nucleus (PBN) to reduce food intake. Investigations of amylin and sCT signaling in the ventral tegmental area (VTA) and nucleus accumbens (NAc) suggest that the eating inhibitory effect of amylin is, in part, mediated through the mesolimbic 'reward' pathway. Indeed, administration of the sCT directly to the VTA decreased phasic dopamine release (DA) in the NAc. However, it is not known if peripheral amylin modulates the mesolimbic system directly or whether this occurs via the AP and PBN. To determine whether and how peripheral amylin or sCT affect mesolimbic reward circuitry we utilized fast scan cyclic voltammetry under anesthesia to measure phasic DA release in the NAc evoked by electrical stimulation of the VTA in intact, AP lesioned and bilaterally PBN lesioned rats. Amylin (50μg/kg i.p.) did not change phasic DA responses compared to saline control rats. However, sCT (50μg/kg i.p.) decreased evoked DA release to VTA-stimulation over 1h compared to saline treated control rats. Further investigations determined that AP and bilateral PBN lesions abolished the ability of sCT to suppress evoked phasic DA responses to VTA-stimulation. These findings implicate the AP and the PBN as important sites for peripheral sCT to decrease evoked DA release in the NAc and suggest that these nuclei may influence hedonic and motivational processes to modulate food intake. Copyright © 2017 Elsevier Inc. All rights reserved.

Direct effect of nicotine on mesolimbic dopamine release in rat nucleus accumbens shell

NARCIS (Netherlands)

Kleijn, J.; Folgering, J. H. A.; van der Hart, M. C. G.; Rollema, H.; Cremers, T. I. F. H.; Westerink, B. H. C.

2011-01-01

Nicotine stimulates dopamine (DA) cell firing via a local action at somatodendritic sites in the ventral tegmental area (VTA), increasing DA release in the nucleus accumbens (NAcc). Additionally, nicotine may also modulate DA release via a direct effect in the NAcc. This study examined the

The effect of low frequency stimulation of the pedunculopontine tegmental nucleus on basal ganglia in a rat model of Parkinson's disease.

Science.gov (United States)

Park, Eunkyoung; Song, Inho; Jang, Dong Pyo; Kim, In Young

2014-08-08

The pedunculopontine nucleus (PPN) has recently been introduced as an alternative target to the subthalamic nucleus (STN) or globus pallidus internus (GPi) for the treatment of advanced Parkinson's disease with severe and medically intractable axial symptoms such as gait and postural impairment. However, it is little known about how electrical stimulation of the PPN affects control of neuronal activities between the PPN and basal ganglia. We examined how low frequency stimulation of the pedunculopontine tegmental nucleus (PPTg) affects control of neuronal activities between the PPN and basal ganglia in 6-OHDA lesioned rats. In order to identify the effect of low frequency stimulation on the PPTg, neuronal activity in both the STN and substantia nigra par reticulata (SNr) were recorded and subjected to quantitative analysis, including analysis of firing rates and firing patterns. In this study, we found that the firing rates of the STN and SNr were suppressed during low frequency stimulation of the PPTg. However, the firing pattern, in contrast to the firing rate, did not exhibit significant changes in either the STN or SNr of 6-OHDA lesioned rats during low frequency stimulation of the PPTg. In addition, we also found that the firing rate of STN and SNr neurons displaying burst and random pattern were decreased by low frequency stimulation of PPTg, while the neurons displaying regular pattern were not affected. These results indicate that low frequency stimulation of the PPTg affects neuronal activity in both the STN and SNr, and may represent electrophysiological efficacy of low frequency PPN stimulation. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

The Role of Neuropeptide Y (NPY) In Uncontrolled Alcohol Drinking and Relapse Behavior Resulting From Exposure to Stressful Events

Science.gov (United States)

2009-11-01

modulating neurobio - logical responses to ethanol and drugs of abuse, including the striatum, nucleus accumbens (NAc), ventral tegmental area (VTA...critically required for the regulation of energy homeostasis in mice. Mol Cell Biol 22, 5027–5035. Rasmussen, D.D., Bryant, C.A., Boldt, B.M., Colasurdo

Brain-derived neurotrophic factor in the ventral midbrain-nucleus accumbens pathway: A role in depression

NARCIS (Netherlands)

Eisch, A.J.; Bolanos, C.A.; de Wit, J.; Simonak, R.D.; Pudiak, C.M.; Barrot, M.; Verhaagen, J.; Nestler, E.J.

2003-01-01

Background: Previous work has shown that brain-derived neurotrophic factor (BDNF) and its receptor, tyrosine kinase receptor B (TrkB), are involved in appetitive behavior. Here we show that BDNF in the ventral tegmental area-nucleus accumbens (VTA-NAc) pathway is also involved in the development of

Transmitter modulation of spike-evoked calcium transients in arousal related neurons

DEFF Research Database (Denmark)

Kohlmeier, Kristi Anne; Leonard, Christopher S

2006-01-01

Nitric oxide synthase (NOS)-containing cholinergic neurons in the laterodorsal tegmentum (LDT) influence behavioral and motivational states through their projections to the thalamus, ventral tegmental area and a brainstem 'rapid eye movement (REM)-induction' site. Action potential-evoked intracel......Nitric oxide synthase (NOS)-containing cholinergic neurons in the laterodorsal tegmentum (LDT) influence behavioral and motivational states through their projections to the thalamus, ventral tegmental area and a brainstem 'rapid eye movement (REM)-induction' site. Action potential......-evoked intracellular calcium transients dampen excitability and stimulate NO production in these neurons. In this study, we investigated the action of several arousal-related neurotransmitters and the role of specific calcium channels in these LDT Ca(2+)-transients by simultaneous whole-cell recording and calcium...... of cholinergic LDT neurons and that inhibition of spike-evoked Ca(2+)-transients is a common action of neurotransmitters that also activate GIRK channels in these neurons. Because spike-evoked calcium influx dampens excitability, our findings suggest that these 'inhibitory' transmitters could boost firing rate...

Activation of midbrain structures by associative novelty and the formation of explicit memory in humans.

Science.gov (United States)

Schott, Björn H; Sellner, Daniela B; Lauer, Corinna-J; Habib, Reza; Frey, Julietta U; Guderian, Sebastian; Heinze, Hans-Jochen; Düzel, Emrah

2004-01-01

Recent evidence suggests a close functional relationship between memory formation in the hippocampus and dopaminergic neuromodulation originating in the ventral tegmental area and medial substantia nigra of the midbrain. Here we report midbrain activation in two functional MRI studies of visual memory in healthy young adults. In the first study, participants distinguished between familiar and novel configurations of pairs of items which had been studied together by either learning the location or the identity of the items. In the second study, participants studied words by either rating the words' pleasantness or counting syllables. The ventral tegmental area and medial substantia nigra showed increased activation by associative novelty (first study) and subsequent free recall performance (second study). In both studies, this activation accompanied hippocampal activation, but was unaffected by the study task. Thus midbrain regions seem to participate selectively in hippocampus-dependent processes of associative novelty and explicit memory formation, but appear to be unaffected by other task-relevant aspects.

High-Surface-Area Nitrogen-Doped Reduced Graphene Oxide for Electric Double-Layer Capacitors.

Science.gov (United States)

Youn, Hee-Chang; Bak, Seong-Min; Kim, Myeong-Seong; Jaye, Cherno; Fischer, Daniel A; Lee, Chang-Wook; Yang, Xiao-Qing; Roh, Kwang Chul; Kim, Kwang-Bum

2015-06-08

A two-step method consisting of solid-state microwave irradiation and heat treatment under NH3 gas was used to prepare nitrogen-doped reduced graphene oxide (N-RGO) with a high specific surface area (1007 m(2)  g(-1) ), high electrical conductivity (1532 S m(-1) ), and low oxygen content (1.5 wt %) for electrical double-layer capacitor applications. The specific capacitance of N-RGO was 291 F g(-1) at a current density of 1 A g(-1) , and a capacitance of 261 F g(-1) was retained at 50 A g(-1) , which indicated a very good rate capability. N-RGO also showed excellent cycling stability and preserved 96 % of the initial specific capacitance after 100 000 cycles. Near-edge X-ray absorption fine-structure spectroscopy results provided evidenced for the recovery of π conjugation in the carbon networks with the removal of oxygenated groups and revealed chemical bonding of the nitrogen atoms in N-RGO. The good electrochemical performance of N-RGO is attributed to its high surface area, high electrical conductivity, and low oxygen content. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Ghrelin signalling on food reward: a salient link between the gut and the mesolimbic system.

Science.gov (United States)

Perello, M; Dickson, S L

2015-06-01

'Hunger is the best spice' is an old and wise saying that acknowledges the fact that almost any food tastes better when we are hungry. The neurobiological underpinnings of this lore include activation of the brain's reward system and the stimulation of this system by the hunger-promoting hormone ghrelin. Ghrelin is produced largely from the stomach and levels are higher preprandially. The ghrelin receptor is expressed in many brain areas important for feeding control, including not only the hypothalamic nuclei involved in energy balance regulation, but also reward-linked areas such as the ventral tegmental area. By targeting the mesoaccumbal dopamine neurones of the ventral tegmental area, ghrelin recruits pathways important for food reward-related behaviours that show overlap with but are also distinct from those important for food intake. We review a variety of studies that support the notion that ghrelin signalling at the level of the mesolimbic system is one of the key molecular substrates that provides a physiological signal connecting gut and reward pathways. © 2014 The Authors. Journal of Neuroendocrinology published by John Wiley & Sons Ltd on behalf of British Society for Neuroendocrinology.

Nicotine Modulates the Long-Lasting Storage of Fear Memory

Science.gov (United States)

Lima, Ramon H.; Radiske, Andressa; Kohler, Cristiano A.; Gonzalez, Maria Carolina; Bevilaqua, Lia R.; Rossato, Janine I.; Medina, Jorge H.; Cammarota, Martin

2013-01-01

Late post-training activation of the ventral tegmental area (VTA)-hippocampus dopaminergic loop controls the entry of information into long-term memory (LTM). Nicotinic acetylcholine receptors (nAChR) modulate VTA function, but their involvement in LTM storage is unknown. Using pharmacological and behavioral tools, we found that…

The Transcription Factor Orthodenticle Homeobox 2 Influences Axonal Projections and Vulnerability of Midbrain Dopaminergic Neurons

Science.gov (United States)

Chung, Chee Yeun; Licznerski, Pawel; Alavian, Kambiz N.; Simeone, Antonio; Lin, Zhicheng; Martin, Eden; Vance, Jeffery; Isacson, Ole

2010-01-01

Two adjacent groups of midbrain dopaminergic neurons, A9 (substantia nigra pars compacta) and A10 (ventral tegmental area), have distinct projections and exhibit differential vulnerability in Parkinson's disease. Little is known about transcription factors that influence midbrain dopaminergic subgroup phenotypes or their potential role in disease.…

Reducing organic contamination of shallow areas in brackish lagoons during rearing fish in cages in polyculture

Directory of Open Access Journals (Sweden)

P. Shekk

2017-07-01

provides a high yield of commercial fish that results in significant additional products with a decrease in pollution level of the water area where the cages are installed. Originality. An original method for rearing marine fish in polyculture in specially designed cages has been developed. The perspective of culturing salmon, mullet and gobies in the polyculture has been demonstrated experimentally. The proposed technology ensures high efficiency of cage mariculture, allows getting additional production through the use of additional facilities and a reduction in the level of organic pollution in shallow water areas where cage farms are located. Practical value. The results of the study can be used to create cage mariculture farms in shallow seaside lagoons. Creating marine fish polyculture in specially designed cages will increase the efficiency of cultivation, reduce feed costs and reduce pollution in shallow water areas.

Developmental Vitamin D (DVD) Deficiency Reduces Nurr1 and TH Expression in Post-mitotic Dopamine Neurons in Rat Mesencephalon.

Science.gov (United States)

Luan, Wei; Hammond, Luke Alexander; Cotter, Edmund; Osborne, Geoffrey William; Alexander, Suzanne Adele; Nink, Virginia; Cui, Xiaoying; Eyles, Darryl Walter

2018-03-01

Developmental vitamin D (DVD) deficiency has been proposed as an important risk factor for schizophrenia. Our previous study using Sprague Dawley rats found that DVD deficiency disrupted the ontogeny of mesencephalic dopamine neurons by decreasing the mRNA level of a crucial differentiation factor of dopamine cells, the nuclear receptor related 1 protein (Nurr1). However, it remains unknown whether this reflects a reduction in dopamine cell number or in Nurr1 expression. It is also unclear if any particular subset of developing dopamine neurons in the mesencephalon is selectively affected. In this study, we employed state-of-the-art spinning disk confocal microscopy optimized for the imaging of tissue sections and 3D segmentation to assess post-mitotic dopamine cells on a single-cell basis in the rat mesencephalon at embryonic day 15. Our results showed that DVD deficiency did not alter the number, morphology, or positioning of post-mitotic dopamine cells. However, the ratio of Nurr1+TH+ cells in the substantia nigra pars compacta (SNc) compared with the ventral tegmental area (VTA) was increased in DVD-deficient embryos. In addition, the expression of Nurr1 in immature dopamine cells and mature dopamine neurons in the VTA was decreased in DVD-deficient group. Tyrosine hydroxylase was selectively reduced in SNc of DVD-deficient mesencephalon. We conclude that DVD deficiency induced early alterations in mesencephalic dopamine development may in part explain the abnormal dopamine-related behaviors found in this model. Our findings may have broader implications for how certain environmental risk factors for schizophrenia may shape the ontogeny of dopaminergic systems and by inference increase the risk of schizophrenia.

A comparative study of collagen dressing versus petrolatum gauze dressing in reducing pain at the donor area

Directory of Open Access Journals (Sweden)

B A Ramesh

2017-01-01

Full Text Available Background: Skin graft is one of the commonly done procedures by plastic surgeons, dermato surgeons and general surgeons. Pain at the donor area is a common complaint by the patient. The skin graft donor site area is usually covered with petrolatum dressing dermatosurgeons. Aim: This study was done to compare collagen dressing with petroleum gauze dressing in control of post-operative pain on skin graft donor area. Materials and Methods: The study was done on forty patients, twenty as study group who received collagen dressing and twenty as control group who received petroleum gauze dressing. The procedure was randomly selected by permutated block size of four. The post-operative pain was assessed with numerical pain rating scale 0 to 10. Nursing staff did the recording of pain scale. The nursing staff was not aware whether patient had collagen or petroleum gauze dressing. Statistics: Statistical analysis used was independent 't'-test (two-sample test and Levene's test. Results: Statistics proved that study group (collagen dressing had lesser pain than control group (petroleum gauze dressing. Conclusion: The collagen sheet dressing on skin graft donor area reduces pain in post-operative period.

Behavioral Specifications of Reward-Associated Long-Term Memory Enhancement in Humans

Science.gov (United States)

Wittmann, Bianca C.; Dolan, Raymond J.; Duzel, Emrah

2011-01-01

Recent functional imaging studies link reward-related activation of the midbrain substantia nigra-ventral tegmental area (SN/VTA), the site of origin of ascending dopaminergic projections, with improved long-term episodic memory. Here, we investigated in two behavioral experiments how (1) the contingency between item properties and reward, (2) the…

Activation of Midbrain Structures by Associative Novelty and the Formation of Explicit Memory in Humans

Science.gov (United States)

Schott, Bjorn H.; Sellner, Daniela B.; Lauer, Corinna-J.; Habib, Reza; Frey, Julietta U.; Guderian, Sebastian; Heinze, Hans-Jochen; Duzel, Emrah

2004-01-01

Recent evidence suggests a close functional relationship between memory formation in the hippocampus and dopaminergic neuromodulation originating in the ventral tegmental area and medial substantia nigra of the midbrain. Here we report midbrain activation in two functional MRI studies of visual memory in healthy young adults. In the first study,…

Maternal high-fat diet during pregnancy and lactation reduces the appetitive behavioral component in female offspring tested in a brief-access taste procedure.

Science.gov (United States)

Treesukosol, Yada; Sun, Bo; Moghadam, Alexander A; Liang, Nu-Chu; Tamashiro, Kellie L; Moran, Timothy H

2014-04-01

Maternal high-fat diet appears to disrupt several energy balance mechanisms in offspring. Here, female offspring from dams fed a high-fat diet (HF) did not significantly differ in body weight compared with those fed chow (CHOW), when weaned onto chow diet. Yet when presented with both a chow and a high-fat diet, high-fat intake was significantly higher in HF compared with CHOW offspring. To assess taste-based responsiveness, offspring (12 wk old) were tested in 30-min sessions (10-s trials) to a sucrose concentration series in a brief-access taste test. Compared with CHOW, the HF offspring initiated significantly fewer trials but did not significantly differ in the amount of concentration-dependent licking. Thus, rather than affect lick response (consummatory), maternal diet affects spout approach (appetitive), which may be attributed to motivation-related mechanisms. Consistent with this possibility, naltrexone, an opioid receptor antagonist, further reduced trial initiation, but not licking in both groups. With naltrexone administration, the group difference in trial initiation was no longer evident, suggesting differences in endogenous opioid activity between the two groups. Relative expression of μ-opioid receptor in the ventral tegmental area was significantly lower in HF rats. When trial initiation was not required in one-bottle intake tests, no main effect of maternal diet on the intake of sucrose and corn oil emulsions was observed. Thus, the maternal high-fat diet-induced difference in diet preference is not likely due to changes in the sensory orosensory component of the taste stimulus but may depend on alterations in satiety signals or absorptive mechanisms.

In situ iron-57 Moessbauer spectroscopic investigations of the effect of titania surface area on the reducibility of titania-supported iron oxide

International Nuclear Information System (INIS)

Berry, F.J.; Du Hongzhang

1990-01-01

Iron-57 Moessbauer spectroscopy has been used to monitor the reducibility in hydrogen of iron oxides supported on titania of differing surface areas. The results show that although Fe 3+ in the iron oxide supported on low surface area titania (11 m 2 g -1 ) is not amenable to facile reduction at low temperatures, complete reduction to metallic iron is achieved by treatment at 600deg C. The data also show that the extent of reduction at elevated temperatures exceeds that which is obtained on similar silica- and alumina-supported systems. Fe 3+ in iron oxide supported on higher surface area titania (50 m 2 g -1 and 240 m 2 g -1 ) is partially reduced in hydrogen at 235deg C to Fe 2+ but fails to attain complete reduction to the metallic state following treatment at 600deg C. The results are related to the different dispersions of iron oxide which can be attained on titania of differing surface area and the consequent interactions between the support and the supported phases. (orig.)

Individual differences in the motivation to communicate relate to levels of midbrain and striatal catecholamine markers in male European starlings

OpenAIRE

Heimovics, Sarah A; Salvante, Katrina G; Sockman, Keith W; Riters, Lauren V

2011-01-01

Individuals display dramatic differences in social communication even within similar social contexts. Across vertebrates dopaminergic projections from the ventral tegmental area (VTA) and midbrain central gray (GCt) strongly influence motivated, reward-directed behaviors. Norepinephrine is also rich in these areas and may alter dopamine neuronal activity. The present study was designed to provide insight into the roles of dopamine and norepinephrine in VTA and GCt and their efferent striatal ...

REDUCING THE IMPACT OF RADIATION FACTORS IN AREAS WITH HIGH LEVEL OF RISK

Directory of Open Access Journals (Sweden)

D. A. Zaredinov

2015-01-01

Full Text Available The article is devoted to the modern problems of radioecology. The study reveals the problems of radioecological situation in some regions of the Republic of Uzbekistan. The main attention of the authors is paid to the ecologically hazardous objects in the uranium mining industry. The characteristics of wastes from uranium mining and stages of development of the mining industry are described. The historical background of the accumulation of the wastes in dumps, the ore-bearing rocks, and other off-balance ores is given. The practical experience and directions radio-ecological safety are generalized, achieving improvements of the environmental quality in areas with high risk. In conclusion, the authors recommend carrying out some measures to reduce an impact of the radiation factor on human health and to stabilize the radioecological situation at the studied regions.

A Free-Choice High-Fat High-Sugar Diet Alters Day-Night Per2 Gene Expression in Reward-Related Brain Areas in Rats.

Science.gov (United States)

Blancas-Velazquez, Aurea Susana; Unmehopa, Unga A; Eggels, Leslie; Koekkoek, Laura; Kalsbeek, Andries; Mendoza, Jorge; la Fleur, Susanne E

2018-01-01

Under normal light-dark conditions, nocturnal rodents consume most of their food during the dark period. Diets high in fat and sugar, however, may affect the day-night feeding rhythm resulting in a higher light phase intake. In vitro and in vivo studies showed that nutrients affect clock-gene expression. We therefore hypothesized that overconsuming fat and sugar alters clock-gene expression in brain structures important for feeding behavior. We determined the effects of a free-choice high-fat high-sugar (fcHFHS) diet on clock-gene expression in rat brain areas related to feeding and reward and compared them with chow-fed rats. Consuming a fcHFHS diet for 6 weeks disrupted day-night differences in Per2 mRNA expression in the nucleus accumbens (NAc) and lateral hypothalamus but not in the suprachiasmatic nucleus, habenula, and ventral tegmental area. Furthermore, short-term sugar drinking, but not fat feeding, upregulates Per2 mRNA expression in the NAc. The disruptions in day-night differences in NAc Per2 gene expression were not accompanied by altered day-night differences in the mRNA expression of peptides related to food intake. We conclude that the fcHFHS diet and acute sugar drinking affect Per2 gene expression in areas involved in food reward; however, this is not sufficient to alter the day-night pattern of food intake.

Central mechanisms of taste: Cognition, emotion and taste-elicited behaviors

Directory of Open Access Journals (Sweden)

Takashi Yamamoto

2008-10-01

Full Text Available Taste is unique among sensory systems in its innate association with mechanisms of reward and aversion in addition to its recognition of quality, e.g., sucrose is sweet and preferable, and quinine is bitter and aversive. Taste information is sent to the reward system and feeding center via the prefrontal cortices such as the mediodorsal and ventrolateral prefrontal cortices in rodents and the orbitofrontal cortex in primates. The amygdala, which receives taste inputs, also influences reward and feeding. In terms of neuroactive substances, palatability is closely related to benzodiazepine derivatives and β-endorphin, both of which facilitate consumption of food and fluid. The reward system contains the ventral tegmental area, nucleus accumbens and ventral pallidum and finally sends information to the lateral hypothalamic area, the feeding center. The dopaminergic system originating from the ventral tegmental area mediates the motivation to consume palatable food. The actual ingestive behavior is promoted by the orexigenic neuropeptides from the hypothalamus. Even palatable food can become aversive and avoided as a consequence of a postingestional unpleasant experience such as malaise. The neural mechanisms of this conditioned taste aversion will also be elucidated.

Saturated Pool Boiling in Vertical Annulus with Reduced Outflow Area

International Nuclear Information System (INIS)

Kang, Myeong Gie

2012-01-01

The mechanisms of pool boiling heat transfer have been studied extensively to design efficient heat transfer devices or to assure the integrity of safety related systems. However, knowledge on pool boiling heat transfer in a confined space is still quite limited. The confined nucleate boiling is an effective technique to enhance heat transfer. Improved heat transfer might be attributed to an increase in the heat transfer coefficient due to vaporization from the thin liquid film on the heating surface or increased bubble activity. According to Cornwell and Houston, the bubbles sliding on the heated surface agitate environmental liquid. In a confined space a kind of pulsating flow due to the bubbles is created and, as a result very active liquid agitation is generated. The increase in the intensity of liquid agitation results in heat transfer enhancement. Sometimes a deterioration of heat transfer appears at high heat fluxes for confined boiling. The cause of the deterioration is suggested as active bubble coalescence. Recently, Kang published inflow effects on pool boiling heat transfer in a vertical annulus with closed bottoms. Kang regulated the gap size at the upper regions of the annulus and identified that effects of the reduced gaps on heat transfer become evident as the heat flux increases. This kind of geometry is found in an in-pile test section. Since more detailed analysis is necessary, effects of the outflow area on nucleate pool boiling heat transfer are investigated in this study. Up to the author's knowledge, no previous results concerning to this effect have been published yet

Enhanced midbrain response at 6-month follow-up in cocaine addiction, association with reduced drug-related choice: Midbrain in drug choice

Energy Technology Data Exchange (ETDEWEB)

Moeller, Scott J.; Tomasi, Dardo; Woicik, Patricia A.; Maloney, Thomas; Alia-Klein, Nelly; Honorio, Jean; Telang, Frank; Wang, Gene-Jack; Wang, Ruiliang; Sinha, Rajita; Carise, Deni; Astone-Twerell, Janetta; Bolger, Joy; Volkow, Nora D.; Goldstein, Rita Z.

2012-03-28

Drug addiction is characterized by dysregulated dopamine neurotransmission. Although dopamine functioning appears to partially recover with abstinence, the specific regions that recover and potential impact on drug seeking remain to be determined. Here we used functional magnetic resonance imaging (fMRI) to study an ecologically valid sample of 15 treatment-seeking cocaine addicted individuals at baseline and 6-month follow-up. At both study sessions, we collected fMRI scans during performance of a drug Stroop task, clinical self-report measures of addiction severity and behavioral measures of cocaine seeking (simulated cocaine choice); actual drug use in between the two study sessions was also monitored. At 6-month follow-up (compared with baseline), we predicted functional enhancement of dopaminergically innervated brain regions, relevant to the behavioral responsiveness toward salient stimuli. Consistent with predictions, whole-brain analyses revealed responses in the midbrain (encompassing the ventral tegmental area/substantia nigra complex) and thalamus (encompassing the mediodorsal nucleus) that were higher (and more positively correlated) at follow-up than baseline. Increased midbrain activity from baseline to follow-up correlated with reduced simulated cocaine choice, indicating that heightened midbrain activations in this context may be marking lower approach motivation for cocaine. Normalization of midbrain function at follow-up was also suggested by exploratory comparisons with active cocaine users and healthy controls (who were assessed only at baseline). Enhanced self-control at follow-up was suggested by a trend for the commonly hypoactive dorsal anterior cingulate cortex to increase response during a drug-related context. Together, these results suggest that fMRI could be useful in sensitively tracking follow-up outcomes in drug addiction.

Reduced activation in the ventral striatum during probabilistic decision-making in patients in an at-risk mental state

Science.gov (United States)

Rausch, Franziska; Mier, Daniela; Eifler, Sarah; Fenske, Sabrina; Schirmbeck, Frederike; Englisch, Susanne; Schilling, Claudia; Meyer-Lindenberg, Andreas; Kirsch, Peter; Zink, Mathias

2015-01-01

Background Patients with schizophrenia display metacognitive impairments, such as hasty decision-making during probabilistic reasoning — the “jumping to conclusion” bias (JTC). Our recent fMRI study revealed reduced activations in the right ventral striatum (VS) and the ventral tegmental area (VTA) to be associated with decision-making in patients with schizophrenia. It is unclear whether these functional alterations occur in the at-risk mental state (ARMS). Methods We administered the classical beads task and fMRI among ARMS patients and healthy controls matched for age, sex, education and premorbid verbal intelligence. None of the ARMS patients was treated with antipsychotics. Both tasks request probabilistic decisions after a variable amount of stimuli. We evaluated activation during decision-making under certainty versus uncertainty and the process of final decision-making. Results We included 24 AMRS patients and 24 controls in our study. Compared with controls, ARMS patients tended to draw fewer beads and showed significantly more JTC bias in the classical beads task, mirroring findings in patients with schizophrenia. During fMRI, ARMS patients did not demonstrate JTC bias on the behavioural level, but showed a significant hypoactivation in the right VS during the decision stage. Limitations Owing to the cross-sectional design of the study, results are constrained to a better insight into the neurobiology of risk constellations, but not pre-psychotic stages. Nine of the ARMS patients were treated with antidepressants and/or lorazepam. Conclusion As in patients with schizophrenia, a striatal hypoactivation was found in ARMS patients. Confounding effects of antipsychotic medication can be excluded. Our findings indicate that error prediction signalling and reward anticipation may be linked to striatal dysfunction during prodromal stages and should be examined for their utility in predicting transition risk. PMID:25622039

Tyrosine hydroxylase immunoreactivity and [3H]WIN 35,428 binding to the dopamine transporter in a hamster model of idiopathic paroxysmal dystonia

International Nuclear Information System (INIS)

Nobrega, J.N.; Gernert, M.; Loescher, W.; Raymond, R.; Belej, T.; Richter, A.

1999-01-01

Recent pharmacological studies and receptor analyses have suggested that dopamine neurotransmission is enhanced in mutant dystonic hamsters (dt sz ), a model of idiopathic paroxysmal dystonia which displays attacks of generalized dystonia in response to mild stress. In order to further characterize the nature of dopamine alterations, the present study investigated possible changes in the number of dopaminergic neurons, as defined by tyrosine hydroxylase immunohistochemistry, as well as binding to the dopamine transporter labelled with [ 3 H]WIN 35,428 in dystonic hamsters. No differences in the number of tyrosine hydroxylase-immunoreactive neurons were found within the substantia nigra and ventral tegmental area of mutant hamsters compared to non-dystonic control hamsters. Similarly, under basal conditions, i.e. in the absence of a dystonic episode, no significant changes in [ 3 H]WIN 35,428 binding were detected in dystonic brains. However, in animals killed during the expression of severe dystonia, significant decreases in dopamine transporter binding became evident in the nucleus accumbens and ventral tegmental area in comparison to controls exposed to the same external stimulation. Since stimulation tended to increase [ 3 H]WIN 35,428 binding in control brains, the observed decrease in the ventral tegmental area appeared to be due primarily to the fact that binding was increased less in dystonic brains than in similarly stimulated control animals.This finding could reflect a diminished ability of the dopamine transporter to undergo adaptive changes in response to external stressful stimulation in mutant hamsters. The selective dopamine uptake inhibitor GBR 12909 (20 mg/kg) aggravated dystonia in mutant hamsters, further suggesting that acute alterations in dopamine transporter function during stimulation may be an important component of dystonia in this model. (Copyright (c) 1999 Elsevier Science B.V., Amsterdam. All rights reserved.)

Tyrosine hydroxylase immunoreactivity and [{sup 3}H]WIN 35,428 binding to the dopamine transporter in a hamster model of idiopathic paroxysmal dystonia

Energy Technology Data Exchange (ETDEWEB)

Nobrega, J.N. [Neuroimaging Research Section, Clarke Institute of Psychiatry, Toronto (Canada); Gernert, M.; Loescher, W. [Department of Pharmacology, Toxicology and Pharmacy, School of Veterinary Medicine, Buenteweg 17, D-30559 Hannover (Germany); Raymond, R.; Belej, T. [Neuroimaging Research Section, Clarke Institute of Psychiatry, Toronto (Canada); Richter, A. [Department of Pharmacology, Toxicology and Pharmacy, School of Veterinary Medicine, Buenteweg 17, D-30559 Hannover (Germany)

1999-08-01

Recent pharmacological studies and receptor analyses have suggested that dopamine neurotransmission is enhanced in mutant dystonic hamsters (dt{sup sz}), a model of idiopathic paroxysmal dystonia which displays attacks of generalized dystonia in response to mild stress. In order to further characterize the nature of dopamine alterations, the present study investigated possible changes in the number of dopaminergic neurons, as defined by tyrosine hydroxylase immunohistochemistry, as well as binding to the dopamine transporter labelled with [{sup 3}H]WIN 35,428 in dystonic hamsters. No differences in the number of tyrosine hydroxylase-immunoreactive neurons were found within the substantia nigra and ventral tegmental area of mutant hamsters compared to non-dystonic control hamsters. Similarly, under basal conditions, i.e. in the absence of a dystonic episode, no significant changes in [{sup 3}H]WIN 35,428 binding were detected in dystonic brains. However, in animals killed during the expression of severe dystonia, significant decreases in dopamine transporter binding became evident in the nucleus accumbens and ventral tegmental area in comparison to controls exposed to the same external stimulation. Since stimulation tended to increase [{sup 3}H]WIN 35,428 binding in control brains, the observed decrease in the ventral tegmental area appeared to be due primarily to the fact that binding was increased less in dystonic brains than in similarly stimulated control animals.This finding could reflect a diminished ability of the dopamine transporter to undergo adaptive changes in response to external stressful stimulation in mutant hamsters. The selective dopamine uptake inhibitor GBR 12909 (20 mg/kg) aggravated dystonia in mutant hamsters, further suggesting that acute alterations in dopamine transporter function during stimulation may be an important component of dystonia in this model. (Copyright (c) 1999 Elsevier Science B.V., Amsterdam. All rights reserved000.

Co-localization patterns of neurotensin receptor 1 and tyrosine hydroxylase in brain regions involved in motivation and social behavior in male European starlings.

Science.gov (United States)

Merullo, Devin P; Spool, Jeremy A; Zhao, Changjiu; Riters, Lauren V

2018-04-01

Animals communicate in distinct social contexts to convey information specific to those contexts, such as sexual or agonistic motivation. In seasonally-breeding male songbirds, seasonal changes in day length and increases in testosterone stimulate sexually-motivated song directed at females for courtship and reproduction. Dopamine and testosterone may act in the same brain regions to stimulate sexually-motivated singing. The neuropeptide neurotensin, acting at the neurotensin receptor 1 (NTR1), can strongly influence dopamine transmission. The goal of this study was to gain insight into the degree to which seasonal changes in physiology modify interactions between neurotensin and dopamine to adjust context-appropriate communication. Male European starlings were examined in physiological conditions that stimulate season-typical forms of communication: late summer/early fall non-breeding condition (low testosterone; birds sing infrequently), late fall non-breeding condition (low testosterone; birds produce non-sexually motivated song), and spring breeding condition (high testosterone; males produce sexually-motivated song). Double fluorescent immunolabeling was performed to detect co-localization patterns between tyrosine hydroxylase (TH; the rate-limiting enzyme in dopamine synthesis) and NTR1 in brain regions implicated in motivation and song production (the ventral tegmental area, medial preoptic nucleus, periaqueductal gray, and lateral septum). Co-localization between TH and NTR1 was present in the ventral tegmental area for all physiological conditions, and the number of co-localized cells did not differ across conditions. Immunolabeling for TH and NTR1 was also present in the other examined regions, although no co-localization was seen. These results support the hypothesis that interactions between NTR1 and dopamine in the ventral tegmental area may modulate vocalizations, but suggest that testosterone- or photoperiod-induced changes in NTR1/TH co

Selective updating of working memory content modulates meso-cortico-striatal activity.

Science.gov (United States)

Murty, Vishnu P; Sambataro, Fabio; Radulescu, Eugenia; Altamura, Mario; Iudicello, Jennifer; Zoltick, Bradley; Weinberger, Daniel R; Goldberg, Terry E; Mattay, Venkata S

2011-08-01

Accumulating evidence from non-human primates and computational modeling suggests that dopaminergic signals arising from the midbrain (substantia nigra/ventral tegmental area) mediate striatal gating of the prefrontal cortex during the selective updating of working memory. Using event-related functional magnetic resonance imaging, we explored the neural mechanisms underlying the selective updating of information stored in working memory. Participants were scanned during a novel working memory task that parses the neurophysiology underlying working memory maintenance, overwriting, and selective updating. Analyses revealed a functionally coupled network consisting of a midbrain region encompassing the substantia nigra/ventral tegmental area, caudate, and dorsolateral prefrontal cortex that was selectively engaged during working memory updating compared to the overwriting and maintenance of working memory content. Further analysis revealed differential midbrain-dorsolateral prefrontal interactions during selective updating between low-performing and high-performing individuals. These findings highlight the role of this meso-cortico-striatal circuitry during the selective updating of working memory in humans, which complements previous research in behavioral neuroscience and computational modeling. Published by Elsevier Inc.

The efficacy of combined educational and site management actions in reducing off-trail hiking in an urban-proximate protected area.

Science.gov (United States)

Hockett, Karen S; Marion, Jeffrey L; Leung, Yu-Fai

2017-12-01

Park and protected area managers are tasked with protecting natural environments, a particularly daunting challenge in heavily visited urban-proximate areas where flora and fauna are already stressed by external threats. In this study, an adaptive management approach was taken to reduce extensive off-trail hiking along a popular trail through an ecologically diverse and significant area in the Chesapeake and Ohio National Historical Park near Washington DC. Substantial amounts of off-trail hiking there had created an extensive 16.1 km network of informal (visitor-created) trails on a 39 ha island in the Potomac Gorge. A research design with additive treatments integrating educational and site management actions was applied and evaluated using self-reported behavior from an on-site visitor survey and unobtrusive observations of off-trail hiking behavior at two locations along the trail. Study treatments included: 1) trailhead educational signs developed using attribution theory and injunctive-proscriptive wording, 2) symbolic "no hiking" prompter signs attached to logs placed across all informal trails, 3) placement of concealing leaf litter and small branches along initial sections of informal trails, 4) restoration work on selected trails with low fencing, and 5) contact with a trail steward to personally communicate the trailhead sign information. The final, most comprehensive treatment reduced visitor-reported intentional off-trail hiking from 70.3% to 43.0%. Direct observations documented reduction in off-trail hiking from 25.9% to 2.0%. The educational message and site management actions both contributed to the decline in off-trail travel and the two evaluation methods enhanced our ability to describe the efficacy of the different treatments in reducing off-trail travel. Published by Elsevier Ltd.

The efficacy of combined educational and site management actions in reducing off-trail hiking in an urban-proximate protected area

Science.gov (United States)

Hockett, Karen; Marion, Jeff; Leung, Yu-Fai

2017-01-01

Park and protected area managers are tasked with protecting natural environments, a particularly daunting challenge in heavily visited urban-proximate areas where flora and fauna are already stressed by external threats. In this study, an adaptive management approach was taken to reduce extensive off-trail hiking along a popular trail through an ecologically diverse and significant area in the Chesapeake and Ohio National Historical Park near Washington DC. Substantial amounts of off-trail hiking there had created an extensive 16.1 km network of informal (visitor-created) trails on a 39 ha island in the Potomac Gorge. A research design with additive treatments integrating educational and site management actions was applied and evaluated using self-reported behavior from an on-site visitor survey and unobtrusive observations of off-trail hiking behavior at two locations along the trail. Study treatments included: 1) trailhead educational signs developed using attribution theory and injunctive-proscriptive wording, 2) symbolic “no hiking” prompter signs attached to logs placed across all informal trails, 3) placement of concealing leaf litter and small branches along initial sections of informal trails, 4) restoration work on selected trails with low fencing, and 5) contact with a trail steward to personally communicate the trailhead sign information. The final, most comprehensive treatment reduced visitor-reported intentional off-trail hiking from 70.3% to 43.0%. Direct observations documented reduction in off-trail hiking from 25.9% to 2.0%. The educational message and site management actions both contributed to the decline in off-trail travel and the two evaluation methods enhanced our ability to describe the efficacy of the different treatments in reducing off-trail travel.

Integrated head area design of KNGR to reduce refueling outage duration

Energy Technology Data Exchange (ETDEWEB)

Jeong, Woo Tae; Park, Chi Yong; Kim, In Hwan; Kim, Dae Woong [Korea Electric Power Research Institute, Taejon (Korea, Republic of)

1998-12-31

In the design of KNGR (Korea Next Generation Reactor), we believe that economy is one of the most important factors to be considered. Thus, we reviewed and evaluated the consequences of designing the head area into an integrated package from an economical point of view. The refueling outage durations of the nuclear power plants currently in operation in Korea, some having and others not having integrated head package, are compared. This paper discusses the characteristics of head area design and the critical design issues of KNGR head area to evaluate the effect of the head area characteristics on the outage duration. 8 refs., 4 figs. (Author)

Integrated head area design of KNGR to reduce refueling outage duration

Energy Technology Data Exchange (ETDEWEB)

Jeong, Woo Tae; Park, Chi Yong; Kim, In Hwan; Kim, Dae Woong [Korea Electric Power Research Institute, Taejon (Korea, Republic of)

1997-12-31

In the design of KNGR (Korea Next Generation Reactor), we believe that economy is one of the most important factors to be considered. Thus, we reviewed and evaluated the consequences of designing the head area into an integrated package from an economical point of view. The refueling outage durations of the nuclear power plants currently in operation in Korea, some having and others not having integrated head package, are compared. This paper discusses the characteristics of head area design and the critical design issues of KNGR head area to evaluate the effect of the head area characteristics on the outage duration. 8 refs., 4 figs. (Author)

Reward and behavioral factors contributing to the tonic activity of monkey pedunculopontine tegmental nucleus neurons during saccade tasks

Directory of Open Access Journals (Sweden)

Ken-ichi Okada

2016-11-01

Full Text Available The pedunculopontine tegmental nucleus (PPTg in the brainstem plays a role in controlling reinforcement learning and executing conditioned behavior. We previously examined activity of PPTg neurons in monkeys during a reward-conditioned, visually guided saccade task, and reported that a population of these neurons exhibited tonic responses throughout the task period. These tonic responses might depend on prediction of the upcoming reward, successful execution of the task, or both. Here, we sought to further distinguish these factors and to investigate how each contributes to the tonic neuronal activity of the PPTg. In our normal visually guided saccade task, the monkey initially fixated on the central fixation target, then made saccades to the peripheral saccade target, and received a juice reward after the saccade target disappeared. Most of the tonic activity terminated shortly after the reward delivery, when the monkey broke fixation. To distinguish between reward and behavioral epochs, we then changed the task sequence for a block of trials, such that the saccade target remained visible after the reward delivery. Under these visible conditions, the monkeys tended to continue fixating on the saccade target even after the reward delivery. Therefore, the prediction of the upcoming reward and the end of an individual trial were separated in time. Regardless of the task conditions, half of the tonically active PPTg neurons terminated their activity around the time of the reward delivery, consistent with the view that PPTg neurons might send reward prediction signals until the time of reward delivery, which is essential for computing reward prediction error in reinforcement learning. On the other hand, the other half of the tonically active PPTg neurons changed their activity dependent on the task condition. In the normal condition, the tonic responses terminated around the time of the reward delivery, while in the visible condition, the activity

Reward and Behavioral Factors Contributing to the Tonic Activity of Monkey Pedunculopontine Tegmental Nucleus Neurons during Saccade Tasks.

Science.gov (United States)

Okada, Ken-Ichi; Kobayashi, Yasushi

2016-01-01

The pedunculopontine tegmental nucleus (PPTg) in the brainstem plays a role in controlling reinforcement learning and executing conditioned behavior. We previously examined the activity of PPTg neurons in monkeys during a reward-conditioned, visually guided saccade task, and reported that a population of these neurons exhibited tonic responses throughout the task period. These tonic responses might depend on prediction of the upcoming reward, successful execution of the task, or both. Here, we sought to further distinguish these factors and to investigate how each contributes to the tonic neuronal activity of the PPTg. In our normal visually guided saccade task, the monkey initially fixated on the central fixation target (FT), then made saccades to the peripheral saccade target and received a juice reward after the saccade target disappeared. Most of the tonic activity terminated shortly after the reward delivery, when the monkey broke fixation. To distinguish between reward and behavioral epochs, we then changed the task sequence for a block of trials, such that the saccade target remained visible after the reward delivery. Under these visible conditions, the monkeys tended to continue fixating on the saccade target even after the reward delivery. Therefore, the prediction of the upcoming reward and the end of an individual trial were separated in time. Regardless of the task conditions, half of the tonically active PPTg neurons terminated their activity around the time of the reward delivery, consistent with the view that PPTg neurons might send reward prediction signals until the time of reward delivery, which is essential for computing reward prediction error in reinforcement learning. On the other hand, the other half of the tonically active PPTg neurons changed their activity dependent on the task condition. In the normal condition, the tonic responses terminated around the time of the reward delivery, while in the visible condition, the activity continued

Expression of the gene encoding the ghrelin receptor in rats selected for differential alcohol preference.

Science.gov (United States)

Landgren, Sara; Engel, Jörgen A; Hyytiä, Petri; Zetterberg, Henrik; Blennow, Kaj; Jerlhag, Elisabet

2011-08-01

The mechanisms involved in alcohol use disorder, a chronic relapsing brain disorder, are complex and involve various signalling systems in the brain. Recently, the orexigenic peptide ghrelin was shown to be required for alcohol-induced reward, an effect mediated via ghrelin receptors, GHS-R1A, at the level of the cholinergic-dopaminergic reward link. Moreover, ghrelin increases and GHR-R1A antagonists reduce moderate alcohol consumption in mice, and a single nucleotide polymorphism in the GHS-R1A gene has been associated with high alcohol consumption in humans. Therefore, GHS-R1A gene expression and alcohol intake were investigated in high, AA (Alko, Alcohol), versus low, ANA (Alko, Non-Alcohol), alcohol consuming rats as well as in Wistar rats. In the AA and ANA rats plasma ghrelin levels were also measured. GHS-R1A gene expression was increased in AA compared to ANA rats in nucleus accumbens, ventral tegmental area, amygdala, prefrontal cortex and hippocampus. A similar trend was observed in the ventral tegmental area of Wistar rats consuming high amounts of alcohol. Furthermore, the AA rats had significantly smaller reduction of plasma ghrelin levels over time, after several weeks of alcohol exposure, than had the ANA rats. The present study provides further evidence for that the ghrelin signalling system, in particular at the level of the mesocortocolimbic dopamine system, is involved in alcohol consumption, and thus possibly contributes to alcohol use disorder. Therefore the GHS-R1A may constitute a novel candidate for development of new treatment strategies for alcohol dependence. Copyright © 2011 Elsevier B.V. All rights reserved.

A simple technique to reduce small bowel toxicity when irradiating the periaortic area

International Nuclear Information System (INIS)

Hernandez, J.C.; Fine, B.; Herman, T.S.; Rothenberg, M.; Nicol, N.

1996-01-01

Purpose/Objective: Patients receiving periaortic radiation are normally treated in the supine position. We decided to evaluate whether positioning the patient prone on a modified 'belly-board' can reduce the volume of small bowel within the lateral fields in patients receiving four field periaortic radiation. Materials and Methods: Sixteen consecutive women with gynecologic primaries underwent simulation of the periaortic area using a four-field set up (AP, PA, Lats). The fields extended from the top of the L1 vertebral body to the bottom of L5 and had a mean length of 16.2 cm. The AP and PA fields had a width of 8 cm (centered on the midline of the vertebral bodies) while the right and left lateral fields had a width of 4 cm (2 cm anterior and 2 cm posterior to the anterior margin of the vertebral bodies) and did not include the spinal cord. Following oral ingestion of small bowel contrast, simulation films were obtained in the supine position and in the prone position on a modified 'belly-board' (with the pelvic opening extended superiorly to the superior abdomen). It was hypothesized that the prone position on a modified 'belly-board' would allow the abdominal small bowel to fall by gravity away from the periaortic area. We measured the volume of small bowel irradiated through the lateral fields for both the supine and prone-in-belly-board positions using the method described by Gallagher et al. Results: The volume of small bowel included within the lateral fields in the supine position ranged from 164 to 359.5 cc 3 (mean 285 cc 3 ) while placement in the prone-in-bellyboard position reduced the volume of small bowel within the lateral fields to a range of 35-152 cc 3 (mean 86 cc 3 ), an overall reduction of approximately 70% in the volume of small bowel included within lateral fields. Conclusion: The use of lateral fields in the prone-in-bellyboard position allows for significant small bowel sparing through the lateral component of a four-field periaortic set

Age-related changes in nicotine response of cholinergic and non-cholinergic laterodorsal tegmental neurons: implications for the heightened adolescent susceptibility to nicotine addiction

Science.gov (United States)

Christensen, Mark H.; Ishibashi, Masaru; Nielsen, Michael L.; Leonard, Christopher S.; Kohlmeier, Kristi A.

2015-01-01

The younger an individual starts smoking, the greater the likelihood that addiction to nicotine will develop, suggesting that neurobiological responses vary across age to the addictive component of cigarettes. Cholinergic neurons of the laterodorsal tegmental nucleus (LDT) are importantly involved in the development of addiction, however, the effects of nicotine on LDT neuronal excitability across ontogeny are unknown. Nicotinic effects on several parameters affecting LDT cells across different age groups were examined using calcium imaging and whole-cell patch clamping. Within the youngest age group (P7-P15), nicotine was found to induce larger intracellular calcium transients and inward currents. Nicotine induced a greater number of excitatory synaptic currents in the youngest animals, whereas larger amplitude inhibitory synaptic events were induced in cells from the oldest animals (P15-P34). Nicotine increased neuronal firing of cholinergic cells to a greater degree in younger animals, possibly linked to development associated differences found in nicotinic effects on action potential shape and afterhyperpolarization. We conclude that in addition to age-associated alterations of several properties expected to affect resting cell excitability, parameters affecting cell excitability are altered by nicotine differentially across ontogeny. Taken together, our data suggest that nicotine induces a larger excitatory response in cholinergic LDT neurons from the youngest animals, which could result in a greater excitatory output from these cells to target regions involved in development of addiction. Such output would be expected to be promotive of addiction; therefore, ontogenetic differences in nicotine-mediated increases in the excitability of the LDT could contribute to the differential susceptibility to nicotine addiction seen across age. PMID:24863041

A novel horizontal subsurface flow constructed wetland: Reducing area requirements and clogging risk.

Science.gov (United States)

Tatoulis, Triantafyllos; Akratos, Christos S; Tekerlekopoulou, Athanasia G; Vayenas, Dimitrios V; Stefanakis, Alexandros I

2017-11-01

The use of Constructed Wetlands (CWs) has been nowadays expanded from municipal to industrial and agro-industrial wastewaters. The main limitations of CWs remain the relatively high area requirements compared to mechanical treatment technologies and the potential occurrence of the clogging phenomenon. This study presents the findings of an innovative CW design where novel materials were used. Four pilot-scale CW units were designed, built and operated for two years. Each unit consisted of two compartments, the first of which (two thirds of the total unit length) contained either fine gravel (in two units) or random type high density polyethylene (HDPE) (in the other two units). This plastic media type was tested in a CW system for the first time. The second compartment of all four units contained natural zeolite. Two units (one with fine gravel and one with HDPE) were planted with common reeds, while the other two were kept unplanted. Second cheese whey was introduced into the units, which were operated under hydraulic residence times (HRT) of 2 and 4 days. After a two-year operation and monitoring period, pollutant removal rates were approximately 80%, 75% and 90% for COD, ammonium and ortho-phosphate, respectively, while temperature and HRT had no significant effect on pollutant removal. CWs containing the plastic media achieved the same removal rates as those containing gravel, despite receiving three times higher hydraulic surface loads (0.08 m/d) and four times higher organic surface loads (620 g/m 2 /d). This reveals that the use of HDPE plastic media could reduce CW surface area requirements by 75%. Copyright © 2017 Elsevier Ltd. All rights reserved.

The role of the central ghrelin system in reward from food and chemical drugs.

Science.gov (United States)

Dickson, Suzanne L; Egecioglu, Emil; Landgren, Sara; Skibicka, Karolina P; Engel, Jörgen A; Jerlhag, Elisabet

2011-06-20

Here we review recent advances that identify a role for the central ghrelin signalling system in reward from both natural rewards (such as food) and artificial rewards (that include alcohol and drugs of abuse). Whereas ghrelin emerged as a stomach-derived hormone involved in energy balance, hunger and meal initiation via hypothalamic circuits, it now seems clear that it also has a role in motivated reward-driven behaviours via activation of the so-called "cholinergic-dopaminergic reward link". This reward link comprises a dopamine projection from the ventral tegmental area (VTA) to the nucleus accumbens together with a cholinergic input, arising primarily from the laterodorsal tegmental area. Ghrelin administration into the VTA or LDTg activates the "cholinergic-dopaminergic" reward link, suggesting that ghrelin may increase the incentive value of motivated behaviours such as reward-seeking behaviour ("wanting" or "incentive motivation"). Further, direct injection of ghrelin into the brain ventricles or into the VTA increases the consumption of rewarding foods as well as alcohol in mice and rats. Studies in rodents show beneficial effects of ghrelin receptor (GHS-R1A) antagonists to suppress the intake of palatable food, to reduce preference for caloric foods, to suppress food reward and motivated behaviour for food. They have also been shown to reduce alcohol consumption, suppress reward induced by alcohol, cocaine and amphetamine. Furthermore, variations in the GHS-R1A and pro-ghrelin genes have been associated with high alcohol consumption, smoking and increased weight gain in alcohol dependent individuals as well as with bulimia nervosa and obesity. Thus, the central ghrelin signalling system interfaces neurobiological circuits involved in reward from food as well as chemical drugs; agents that directly or indirectly suppress this system emerge as potential candidate drugs for suppressing problematic over-eating that leads to obesity as well as for the

Marijuana and cannabinoid regulation of brain reward circuits

OpenAIRE

Lupica, Carl R; Riegel, Arthur C; Hoffman, Alexander F

2004-01-01

The reward circuitry of the brain consists of neurons that synaptically connect a wide variety of nuclei. Of these brain regions, the ventral tegmental area (VTA) and the nucleus accumbens (NAc) play central roles in the processing of rewarding environmental stimuli and in drug addiction. The psychoactive properties of marijuana are mediated by the active constituent, Δ9-THC, interacting primarily with CB1 cannabinoid receptors in a large number of brain areas. However, it is the activation o...

Optimized mixed oils remarkably reduce the amount of surfactants in microemulsions without affecting oral bioavailability of ibuprofen by simultaneously enlarging microemulsion areas and enhancing drug solubility.

Science.gov (United States)

Chen, Yizhen; Tuo, Jue; Huang, Huizhi; Liu, Dan; You, Xiuhua; Mai, Jialuo; Song, Jiaqi; Xie, Yanqi; Wu, Chuanbin; Hu, Haiyan

2015-06-20

The toxicity and irritation associated with high amounts of surfactants restrict the extensive utilization of microemulsions. To address these shortcomings, employing mixed oils to enlarge microemulsion areas therefore reducing surfactant contents is a promising strategy. However, what kinds of mixed oils are more efficient in enlarging microemulsion areas still remains unclear. In this research, we found that the chain length and degree of unsaturation of oils play a key role in enlarging microemulsion areas. The combination of moderate chain saturated oil caprylic/capric triglyceride (GTCC) with long chain unsaturated oil glycerol trioleate significantly increased the microemulsion areas. Solubility of ibuprofen in the mixed oils was unexpectedly and remarkably increased (almost 300mg/mL) compared with that (around 100mg/mL) of the single oil (GTCC), which also resulted in greatly increased solubility of ibuprofen in mixed oils-containing microemulsions. By optimizing the mixed oil formulation, the absolute amount of surfactant in drug-loaded microemulsions was reduced but increased drug oral bioavailability in rats was maintained. It could be concluded that the combined use of moderate chain oils and long chain unsaturated oils could not only acquire enlarged microemulsion areas but also enhanced drug solubility, therefore doubly reducing surfactant amount, which is extremely beneficial for developing safe microemulsions. Copyright © 2015. Published by Elsevier B.V.

Neuropharmacological mechanisms of drug reward: beyond dopamine in the nucleus accumbens.

Science.gov (United States)

Bardo, M T

1998-01-01

Multiple lines of research have implicated the mesolimbic dopamine system in drug reward measured by either the drug self-administration or conditioned place preference paradigm. The present review summarizes recent work that examines the neuropharmacological mechanisms by which drugs impinge on this dopaminergic neural circuitry, as well as other systems that provide input and output circuits to the mesolimbic dopamine system. Studies examining the effect of selective agonist and antagonist drugs administered systemically have indicated that multiple neurotransmitters are involved, including dopamine, serotonin, acetylcholine, glutamate, GABA, and various peptides. Direct microinjection studies have also provided crucial evidence indicating that, in addition to the mesolimbic dopamine system, other structures play a role in drug reward, including the ventral pallidum, amygdala, hippocampus, hypothalamus, and pedunculopontine tegmental nucleus. GABAergic circuitry descending from the nucleus accumbens to the pedunculopontine tegmental nucleus via the ventral pallidum appears to be especially important in directing the behavioral sequelae associated with reward produced by various drugs of abuse. However, activation of the reward circuitry is achieved differently for various drugs of abuse. With amphetamine and cocaine, initiation of reward is controlled within the nucleus accumbens and prefrontal cortex, respectively. With opiates, initiation of reward involves the ventral tegmental area, nucleus accumbens, hippocampus, and hypothalamus. It is not clear presently if these multiple anatomical structures mediate opiate reward by converging on a single output system or multiple output systems.

SECTIONAL AREA CALCULATION OF MATERIAL REMOVED FROM BLANK WHILE FORMING SPACE BETWEEN TWO TEETH OF SATELLITE GEAR OF PLANETARY PIN TOOTH REDUCER

Directory of Open Access Journals (Sweden)

N. G. Yankevich

2009-01-01

Full Text Available One of the most important values while forming gear wheels is a material section area Sс which is to be removed by a tool in the process of forming a space between two teeth in one pass. Cutting resistance which is proportional  to section area of  the layer to be cut and, correspondingly, a thermodynamic intensity in the polishing zone depend on Sс value.The paper proposes relations for calculation of a material section area Sс which is to be removed from a blank while forming a space between two teeth of a satellite gear of a planetary pin tooth reducer.Measurements being made in the AutoCAD packet have shown that any corrections of the profile do not make a significant influence on a section area Sс.

Reward, motivation, and emotion systems associated with early-stage intense romantic love.

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Aron, Arthur; Fisher, Helen; Mashek, Debra J; Strong, Greg; Li, Haifang; Brown, Lucy L

2005-07-01

Early-stage romantic love can induce euphoria, is a cross-cultural phenomenon, and is possibly a developed form of a mammalian drive to pursue preferred mates. It has an important influence on social behaviors that have reproductive and genetic consequences. To determine which reward and motivation systems may be involved, we used functional magnetic resonance imaging and studied 10 women and 7 men who were intensely "in love" from 1 to 17 mo. Participants alternately viewed a photograph of their beloved and a photograph of a familiar individual, interspersed with a distraction-attention task. Group activation specific to the beloved under the two control conditions occurred in dopamine-rich areas associated with mammalian reward and motivation, namely the right ventral tegmental area and the right postero-dorsal body and medial caudate nucleus. Activation in the left ventral tegmental area was correlated with facial attractiveness scores. Activation in the right anteromedial caudate was correlated with questionnaire scores that quantified intensity of romantic passion. In the left insula-putamen-globus pallidus, activation correlated with trait affect intensity. The results suggest that romantic love uses subcortical reward and motivation systems to focus on a specific individual, that limbic cortical regions process individual emotion factors, and that there is localization heterogeneity for reward functions in the human brain.

Smoking cessation programmes in radon affected areas: can they make a significant contribution to reducing radon-induced lung cancers?

International Nuclear Information System (INIS)

Denman, A.R.; Groves-Kirkby, C.J.; Timson, K.; Shield, G.; Rogers, S.; Phillips, P.S.

2008-01-01

Domestic radon levels in parts of the UK are sufficiently high to increase the risk of lung cancer in the occupants. Public health campaigns in Northamptonshire, a designated radon affected area with 6.3% of homes having average radon levels over the UK action level of 200 Bq m -3 , have encouraged householders to test for radon and then to carry out remediation in their homes, but have been only partially successful. Only 40% of Northamptonshire houses have been tested, and only 15% of householders finding raised levels proceed to remediate. Of those who did remediate, only 9% smoked, compared to a countywide average of 28.8%. This is unfortunate, since radon and smoking combine to place the individual at higher risk by a factor of around 4, and suggests that current strategies to reduce domestic radon exposure are not reaching those most at risk. During 2004-5, the NHS Stop Smoking Services in Northamptonshire assisted 2,808 smokers to quit to the 4-week stage, with some 30% of 4-week quitters remaining quitters at 1 year. We consider whether smoking cessation campaigns make significant contributions to radon risk reduction on their own, by assessing individual occupants' risk of developing lung cancer from knowledge of their age, gender, and smoking habits, together with he radon level in their house. The results demonstrate that smoking cessation programmes have significant added value in radon affected areas, and contribute a greater health benefit than reducing radon levels in the smokers' homes, whilst they remain smokers. Additionally, results are presented from a questionnaire-based survey of quitters, addressing their reasons for seeking help in quitting smoking, and whether knowledge of radon risks influenced this decision. The impact of these findings on future public health campaigns to reduce the impact of radon and smoking are discussed. (author)

Galanin-Expressing GABA Neurons in the Lateral Hypothalamus Modulate Food Reward and Noncompulsive Locomotion

OpenAIRE

Qualls-Creekmore, Emily; Yu, Sangho; Francois, Marie; Hoang, John; Huesing, Clara; Bruce-Keller, Annadora; Burk, David; Berthoud, Hans-Rudolf; Morrison, Christopher D.; Münzberg, Heike

2017-01-01

The lateral hypothalamus (LHA) integrates reward and appetitive behavior and is composed of many overlapping neuronal populations. Recent studies associated LHA GABAergic neurons (LHAGABA), which densely innervate the ventral tegmental area (VTA), with modulation of food reward and consumption; yet, LHAGABA projections to the VTA exclusively modulated food consumption, not reward. We identified a subpopulation of LHAGABA neurons that coexpress the neuropeptide galanin (LHAGal). These LHAGal n...

Recreational Trails Reduce the Density of Ground-Dwelling Birds in Protected Areas

Science.gov (United States)

Thompson, Bill

2015-05-01

Recreational disturbance associated with trails has been identified as one of the major factors causing a decline of native biodiversity within protected areas. However, despite the negative impacts that recreation can have on biodiversity, providing public access to nature is critical for the future of the conservation of biodiversity. As such, many protected area managers are looking for tools to help maintain a balance between public access and biodiversity conservation. The objectives of this study were to examine the impacts of recreational trails on forest-dwelling bird communities in eastern North America, identify functional guilds which are particularly sensitive to recreational trails, and derive guidelines for trail design to assist in managing the impacts of recreational trails on forest-dwelling birds. Trails within 24 publicly owned natural areas were mapped, and breeding bird communities were described with the use of point count surveys. The density of forest birds, particularly of those species which nest or forage on the ground, were significantly positively influenced by the amount of trail-free refuge habitat. Although management options to control trail use in non-staffed protected areas are limited, this study suggests that protected area managers could design and maintain a trail network that would minimize impacts on resident wildlife, while providing recreational opportunities for visitors, by designing their trail network to maximize the area of trail-free habitat.

Recreational trails reduce the density of ground-dwelling birds in protected areas.

Science.gov (United States)

Thompson, Bill

2015-05-01

Recreational disturbance associated with trails has been identified as one of the major factors causing a decline of native biodiversity within protected areas. However, despite the negative impacts that recreation can have on biodiversity, providing public access to nature is critical for the future of the conservation of biodiversity. As such, many protected area managers are looking for tools to help maintain a balance between public access and biodiversity conservation. The objectives of this study were to examine the impacts of recreational trails on forest-dwelling bird communities in eastern North America, identify functional guilds which are particularly sensitive to recreational trails, and derive guidelines for trail design to assist in managing the impacts of recreational trails on forest-dwelling birds. Trails within 24 publicly owned natural areas were mapped, and breeding bird communities were described with the use of point count surveys. The density of forest birds, particularly of those species which nest or forage on the ground, were significantly positively influenced by the amount of trail-free refuge habitat. Although management options to control trail use in non-staffed protected areas are limited, this study suggests that protected area managers could design and maintain a trail network that would minimize impacts on resident wildlife, while providing recreational opportunities for visitors, by designing their trail network to maximize the area of trail-free habitat.

Historical harvests reduce neighboring old-growth basal area across a forest landscape.

Science.gov (United States)

Bell, David M; Spies, Thomas A; Pabst, Robert

2017-07-01

While advances in remote sensing have made stand, landscape, and regional assessments of the direct impacts of disturbance on forests quite common, the edge influence of timber harvesting on the structure of neighboring unharvested forests has not been examined extensively. In this study, we examine the impact of historical timber harvests on basal area patterns of neighboring old-growth forests to assess the magnitude and scale of harvest edge influence in a forest landscape of western Oregon, USA. We used lidar data and forest plot measurements to construct 30-m resolution live tree basal area maps in lower and middle elevation mature and old-growth forests. We assessed how edge influence on total, upper canopy, and lower canopy basal area varied across this forest landscape as a function of harvest characteristics (i.e., harvest size and age) and topographic conditions in the unharvested area. Upper canopy, lower canopy, and total basal area increased with distance from harvest edge and elevation. Forests within 75 m of harvest edges (20% of unharvested forests) had 4% to 6% less live tree basal area compared with forest interiors. An interaction between distance from harvest edge and elevation indicated that elevation altered edge influence in this landscape. We observed a positive edge influence at low elevations (800 m). Surprisingly, we found no or weak effects of harvest age (13-60 yr) and harvest area (0.2-110 ha) on surrounding unharvested forest basal area, implying that edge influence was relatively insensitive to the scale of disturbance and multi-decadal recovery processes. Our study indicates that the edge influence of past clearcutting on the structure of neighboring uncut old-growth forests is widespread and persistent. These indirect and diffuse legacies of historical timber harvests complicate forest management decision-making in old-growth forest landscapes by broadening the traditional view of stand boundaries. Furthermore, the consequences

Using the area under the curve to reduce measurement error in predicting young adult blood pressure from childhood measures.

Science.gov (United States)

Cook, Nancy R; Rosner, Bernard A; Chen, Wei; Srinivasan, Sathanur R; Berenson, Gerald S

2004-11-30

Tracking correlations of blood pressure, particularly childhood measures, may be attenuated by within-person variability. Combining multiple measurements can reduce this error substantially. The area under the curve (AUC) computed from longitudinal growth curve models can be used to improve the prediction of young adult blood pressure from childhood measures. Quadratic random-effects models over unequally spaced repeated measures were used to compute the area under the curve separately within the age periods 5-14 and 20-34 years in the Bogalusa Heart Study. This method adjusts for the uneven age distribution and captures the underlying or average blood pressure, leading to improved estimates of correlation and risk prediction. Tracking correlations were computed by race and gender, and were approximately 0.6 for systolic, 0.5-0.6 for K4 diastolic, and 0.4-0.6 for K5 diastolic blood pressure. The AUC can also be used to regress young adult blood pressure on childhood blood pressure and childhood and young adult body mass index (BMI). In these data, while childhood blood pressure and young adult BMI were generally directly predictive of young adult blood pressure, childhood BMI was negatively correlated with young adult blood pressure when childhood blood pressure was in the model. In addition, racial differences in young adult blood pressure were reduced, but not eliminated, after controlling for childhood blood pressure, childhood BMI, and young adult BMI, suggesting that other genetic or lifestyle factors contribute to this difference. 2004 John Wiley & Sons, Ltd.

Differences in regional grey matter volumes in currently ill patients with anorexia nervosa.

Science.gov (United States)

Phillipou, Andrea; Rossell, Susan Lee; Gurvich, Caroline; Castle, David Jonathan; Abel, Larry Allen; Nibbs, Richard Grant; Hughes, Matthew Edward

2018-01-01

Neurobiological findings in anorexia nervosa (AN) are inconsistent, including differences in regional grey matter volumes. Methodological limitations often contribute to the inconsistencies reported. The aim of this study was to improve on these methodologies by utilising voxel-based morphometry (VBM) analysis with the use of diffeomorphic anatomic registration through an exponentiated lie algebra algorithm (DARTEL), in a relatively large group of individuals with AN. Twenty-six individuals with AN and 27 healthy controls underwent a T1-weighted magnetic resonance imaging (MRI) scan. AN participants were found to have reduced grey matter volumes in a number of areas including regions of the basal ganglia (including the ventral striatum), and parietal and temporal cortices. Body mass index (BMI) and global scores on the Eating Disorder Examination Questionnaire (EDE-Q) were also found to correlate with grey matter volumes in a region of the brainstem (including the substantia nigra and ventral tegmental area) in AN, and predicted 56% of the variance in grey matter volumes in this area. The brain regions associated with grey matter reductions in AN are consistent with regions responsible for cognitive deficits associated with the illness including anhedonia, deficits in affect perception and saccadic eye movement abnormalities. Overall, the findings suggest reduced grey matter volumes in AN that are associated with eating disorder symptomatology. © 2017 Federation of European Neuroscience Societies and John Wiley & Sons Ltd.

Cocaine abstinence following chronic treatment alters cerebral metabolism in dopaminergic reward regions. Bromocriptine enhances recovery

International Nuclear Information System (INIS)

Clow, D.W.; Hammer, R.P. Jr.

1991-01-01

2-[14C]deoxyglucose autoradiography was used to determine local cerebral glucose utilization (lCGU) in rats following chronic cocaine treatment and subsequent abstinence. lCGU was examined in 43 discrete brain regions in animals which had received daily injections of cocaine for 14 days (10 mg/kg) followed by 3 days of saline or bromocriptine (10 mg/kg) treatment. Cocaine abstinence following chronic treatment significantly reduced lCGU in several regions including mesocorticolimbic structures such as ventral tegmental area, medial prefrontal cortex, and nucleus accumbens (NAc). Within the NAc, however, only the rostral pole showed significant reduction. In contrast, when bromocriptine treatment accompanied abstinence, lCGU was no longer reduced in mesocorticolimbic and most other regions, implying that metabolic recovery was enhanced by bromocriptine treatment during early abstinence following chronic cocaine treatment. These data suggest that cerebral metabolism is decreased during cocaine abstinence following chronic treatment in critical brain regions, and that this alteration can be prevented by treatment with direct-acting dopamine agonists such as bromocriptine

Cocaine abstinence following chronic treatment alters cerebral metabolism in dopaminergic reward regions. Bromocriptine enhances recovery

Energy Technology Data Exchange (ETDEWEB)

Clow, D.W.; Hammer, R.P. Jr. (Univ. of Hawaii School of Medicine, Honolulu (USA))

1991-01-01

2-(14C)deoxyglucose autoradiography was used to determine local cerebral glucose utilization (lCGU) in rats following chronic cocaine treatment and subsequent abstinence. lCGU was examined in 43 discrete brain regions in animals which had received daily injections of cocaine for 14 days (10 mg/kg) followed by 3 days of saline or bromocriptine (10 mg/kg) treatment. Cocaine abstinence following chronic treatment significantly reduced lCGU in several regions including mesocorticolimbic structures such as ventral tegmental area, medial prefrontal cortex, and nucleus accumbens (NAc). Within the NAc, however, only the rostral pole showed significant reduction. In contrast, when bromocriptine treatment accompanied abstinence, lCGU was no longer reduced in mesocorticolimbic and most other regions, implying that metabolic recovery was enhanced by bromocriptine treatment during early abstinence following chronic cocaine treatment. These data suggest that cerebral metabolism is decreased during cocaine abstinence following chronic treatment in critical brain regions, and that this alteration can be prevented by treatment with direct-acting dopamine agonists such as bromocriptine.

Midbrain Gene Screening Identifies a New Mesoaccumbal Glutamatergic Pathway and a Marker for Dopamine Cells Neuroprotected in Parkinson?s Disease

OpenAIRE

Viereckel, Thomas; Dumas, Sylvie; Smith-Anttila, Casey J. A.; Vlcek, Bianca; Bimpisidis, Zisis; Lagerstr?m, Malin C.; Konradsson-Geuken, ?sa; Wall?n-Mackenzie, ?sa

2016-01-01

The ventral tegmental area (VTA) and substantia nigra pars compacta (SNc) of the midbrain are associated with Parkinson's disease (PD), schizophrenia, mood disorders and addiction. Based on the recently unraveled heterogeneity within the VTA and SNc, where glutamate, GABA and co-releasing neurons have been found to co-exist with the classical dopamine neurons, there is a compelling need for identification of gene expression patterns that represent this heterogeneity and that are of value for ...

Dorsolateral Prefrontal Cortex Drives Mesolimbic Dopaminergic Regions to Initiate Motivated Behavior

OpenAIRE

Ballard, Ian C.; Murty, Vishnu P.; Carter, R. McKell; MacInnes, Jeffrey J.; Huettel, Scott A.; Adcock, R. Alison

2011-01-01

How does the brain translate information signaling potential rewards into motivation to get them? Motivation to obtain reward is thought to depend on the midbrain, (particularly the ventral tegmental area, VTA), the nucleus accumbens (NAcc), and the dorsolateral prefrontal cortex (dlPFC), but it is not clear how the interactions amongst these regions relate to reward-motivated behavior. To study the influence of motivation on these reward-responsive regions and on their interactions, we used ...

Reorganization of circuits underlying cerebellar modulation of prefrontal cortical dopamine in mouse models of autism spectrum disorder

OpenAIRE

Rogers, Tiffany D.; Dickson, Price E.; McKimm, Eric; Heck, Detlef H.; Goldowitz, Dan; Blaha, Charles D.; Mittleman, Guy

2013-01-01

Imaging, clinical and pre-clinical studies have provided ample evidence for a cerebellar involvement in cognitive brain function including cognitive brain disorders, such as autism and schizophrenia. We previously reported that cerebellar activity modulates dopamine release in the mouse medial prefrontal cortex (mPFC) via two distinct pathways: (1) cerebellum to mPFC via dopaminergic projections from the ventral tegmental area [VTA] and (2) cerebellum to mPFC via glutamatergic projections fro...

Menthol Enhances Nicotine Reward-Related Behavior by Potentiating Nicotine-Induced Changes in nAChR Function, nAChR Upregulation, and DA Neuron Excitability.

Science.gov (United States)

Henderson, Brandon J; Wall, Teagan R; Henley, Beverley M; Kim, Charlene H; McKinney, Sheri; Lester, Henry A

2017-11-01

Understanding why the quit rate among smokers of menthol cigarettes is lower than non-menthol smokers requires identifying the neurons that are altered by nicotine, menthol, and acetylcholine. Dopaminergic (DA) neurons in the ventral tegmental area (VTA) mediate the positive reinforcing effects of nicotine. Using mouse models, we show that menthol enhances nicotine-induced changes in nicotinic acetylcholine receptors (nAChRs) expressed on midbrain DA neurons. Menthol plus nicotine upregulates nAChR number and function on midbrain DA neurons more than nicotine alone. Menthol also enhances nicotine-induced changes in DA neuron excitability. In a conditioned place preference (CPP) assay, we observed that menthol plus nicotine produces greater reward-related behavior than nicotine alone. Our results connect changes in midbrain DA neurons to menthol-induced enhancements of nicotine reward-related behavior and may help explain how smokers of menthol cigarettes exhibit reduced cessation rates.

Desulfofrigus sp. prevails in sulfate-reducing dilution cultures from sediments of the Benguela upwelling area.

Science.gov (United States)

Kraft, Beate; Engelen, Bert; Goldhammer, Tobias; Lin, Yu-Shih; Cypionka, Heribert; Könneke, Martin

2013-04-01

Sediments of coastal upwelling areas are generally characterized by a high content of organic carbon that is mainly degraded via anaerobic microbial processes including sulfate reduction as a major terminal oxidation step. Despite the high importance of sulfate reduction in these sediments, the identity of sulfate-reducing bacteria (SRB) has remained almost unknown. Here, we applied a cultivation-based approach using selective enrichment conditions to study the diversity and distribution of active SRB in sediments along a transect perpendicular to the continental slope off the coast of Namibia (Meteor-cruise M76/1). To promote growth of the most abundant SRB, dilution series were prepared and amended with hydrogen, acetate, or a mixture of monomers representing typical substrates for SRB. Growth of SRB could be detected in the presence of all electron donors and from sediment down to 4 m depth. 16S rRNA gene-based DGGE analysis and sequencing revealed the predominance of SRB related to psychrophiles in particular to the genus Desulfofrigus, which made up 1 % of the total microbial community, accounting for an absolute abundance of up to 4.8 × 10(7)  cells mL(-1) . In general, the abundance of cultured SRB changed with depth and between the different sampling sites and correlated with the content of organic carbon as previously reported. Growth of chemolithotrophic SRB in relatively high dilution steps and the enrichment of methanogens as well as acetogens from deeper sediment point to a competition between hydrogen-utilizing microbial processes and their biogeochemical significance in deep sediment layers of the Benguela upwelling area. © 2012 Federation of European Microbiological Societies. Published by Blackwell Publishing Ltd. All rights reserved.

Place field assembly distribution encodes preferred locations.

Directory of Open Access Journals (Sweden)

Omar Mamad

2017-09-01

Full Text Available The hippocampus is the main locus of episodic memory formation and the neurons there encode the spatial map of the environment. Hippocampal place cells represent location, but their role in the learning of preferential location remains unclear. The hippocampus may encode locations independently from the stimuli and events that are associated with these locations. We have discovered a unique population code for the experience-dependent value of the context. The degree of reward-driven navigation preference highly correlates with the spatial distribution of the place fields recorded in the CA1 region of the hippocampus. We show place field clustering towards rewarded locations. Optogenetic manipulation of the ventral tegmental area demonstrates that the experience-dependent place field assembly distribution is directed by tegmental dopaminergic activity. The ability of the place cells to remap parallels the acquisition of reward context. Our findings present key evidence that the hippocampal neurons are not merely mapping the static environment but also store the concurrent context reward value, enabling episodic memory for past experience to support future adaptive behavior.

Expression of peroxisome proliferator-activated receptor-gamma in key neuronal subsets regulating glucose metabolism and energy homeostasis.

Science.gov (United States)

Sarruf, David A; Yu, Fang; Nguyen, Hong T; Williams, Diana L; Printz, Richard L; Niswender, Kevin D; Schwartz, Michael W

2009-02-01

In addition to increasing insulin sensitivity and adipogenesis, peroxisome proliferator-activated receptor (PPAR)-gamma agonists cause weight gain and hyperphagia. Given the central role of the brain in the control of energy homeostasis, we sought to determine whether PPARgamma is expressed in key brain areas involved in metabolic regulation. Using immunohistochemistry, PPARgamma distribution and its colocalization with neuron-specific protein markers were investigated in rat and mouse brain sections spanning the hypothalamus, the ventral tegmental area, and the nucleus tractus solitarius. In several brain areas, nuclear PPARgamma immunoreactivity was detected in cells that costained for neuronal nuclei, a neuronal marker. In the hypothalamus, PPARgamma immunoreactivity was observed in a majority of neurons in the arcuate (including both agouti related protein and alpha-MSH containing cells) and ventromedial hypothalamic nuclei and was also present in the hypothalamic paraventricular nucleus, the lateral hypothalamic area, and tyrosine hydroxylase-containing neurons in the ventral tegmental area but was not expressed in the nucleus tractus solitarius. To validate and extend these histochemical findings, we generated mice with neuron-specific PPARgamma deletion using nestin cre-LoxP technology. Compared with littermate controls, neuron-specific PPARgamma knockout mice exhibited dramatic reductions of both hypothalamic PPARgamma mRNA levels and PPARgamma immunoreactivity but showed no differences in food intake or body weight over a 4-wk study period. We conclude that: 1) PPARgamma mRNA and protein are expressed in the hypothalamus, 2) neurons are the predominant source of PPARgamma in the central nervous system, although it is likely expressed by nonneuronal cell types as well, and 3) arcuate nucleus neurons that control energy homeostasis and glucose metabolism are among those in which PPARgamma is expressed.

Reducing the capacitance of piezoelectric film sensors

Energy Technology Data Exchange (ETDEWEB)

González, Martín G., E-mail: mggonza@fi.uba.ar [Grupo de Láser, Óptica de Materiales y Aplicaciones Electromagnéticas (GLOMAE), Departamento de Física, Facultad de Ingeniería, Universidad de Buenos Aires, Paseo Colón 850, C1063ACV Buenos Aires (Argentina); Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), C1425FQB Buenos Aires (Argentina); Sorichetti, Patricio A.; Santiago, Guillermo D. [Grupo de Láser, Óptica de Materiales y Aplicaciones Electromagnéticas (GLOMAE), Departamento de Física, Facultad de Ingeniería, Universidad de Buenos Aires, Paseo Colón 850, C1063ACV Buenos Aires (Argentina)

2016-04-15

We present a novel design for large area, wideband, polymer piezoelectric sensor with low capacitance. The large area allows better spatial resolution in applications such as photoacoustic tomography and the reduced capacitance eases the design of fast transimpedance amplifiers. The metalized piezoelectric polymer thin film is segmented into N sections, electrically connected in series. In this way, the total capacitance is reduced by a factor 1/N{sup 2}, whereas the mechanical response and the active area of the sensor are not modified. We show the construction details for a two-section sensor, together with the impedance spectroscopy and impulse response experimental results that validate the design.

Reducing the capacitance of piezoelectric film sensors

International Nuclear Information System (INIS)

González, Martín G.; Sorichetti, Patricio A.; Santiago, Guillermo D.

2016-01-01

We present a novel design for large area, wideband, polymer piezoelectric sensor with low capacitance. The large area allows better spatial resolution in applications such as photoacoustic tomography and the reduced capacitance eases the design of fast transimpedance amplifiers. The metalized piezoelectric polymer thin film is segmented into N sections, electrically connected in series. In this way, the total capacitance is reduced by a factor 1/N"2, whereas the mechanical response and the active area of the sensor are not modified. We show the construction details for a two-section sensor, together with the impedance spectroscopy and impulse response experimental results that validate the design.

Serotonin regulates brain-derived neurotrophic factor expression in select brain regions during acute psychological stress

Institute of Scientific and Technical Information of China (English)

De-guo Jiang; Shi-li Jin; Gong-ying Li; Qing-qing Li; Zhi-ruo Li; Hong-xia Ma; Chuan-jun Zhuo; Rong-huan Jiang; Min-jie Ye

2016-01-01

Previous studies suggest that serotonin (5-HT) might interact with brain-derived neurotrophic factor (BDNF) during the stress response. However, the relationship between 5-HT and BDNF expression under purely psychological stress is unclear. In this study, one hour before psychological stress exposure, the 5-HT1A receptor agonist 8-OH-DPAT or antagonist MDL73005, or the 5-HT2A receptor agonist DOI or antagonist ketanserin were administered to rats exposed to psychological stress. Immunohistochemistry andin situ hybridization revealed that after psychological stress, with the exception of the ventral tegmental area, BDNF protein and mRNA expression levels were higher in the 5-HT1A and the 5-HT2A receptor agonist groups compared with the solvent control no-stress or psychological stress group in the CA1 and CA3 of the hippocampus, prefrontal cortex, central amygdaloid nucleus, dorsomedial hypothalamic nucleus, dentate gyrus, shell of the nucleus accumbens and the midbrain periaqueductal gray. There was no signiifcant difference between the two agonist groups. In contrast, after stress exposure, BDNF protein and mRNA expression levels were lower in the 5-HT1A and 5-HT2A receptor antagonist groups than in the solvent control non-stress group, with the exception of the ventral tegmental area. Our ifndings suggest that 5-HT regulates BDNF expression in a rat model of acute psychological stress.

Endocannabinoids shape accumbal encoding of cue-motivated behavior via CB1 receptor activation in the ventral tegmentum.

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Oleson, Erik B; Beckert, Michael V; Morra, Joshua T; Lansink, Carien S; Cachope, Roger; Abdullah, Rehab A; Loriaux, Amy L; Schetters, Dustin; Pattij, Tommy; Roitman, Mitchell F; Lichtman, Aron H; Cheer, Joseph F

2012-01-26

Transient increases in nucleus accumbens (NAc) dopamine concentration are observed when animals are presented with motivationally salient stimuli and are theorized to energize reward seeking. They arise from high-frequency firing of dopamine neurons in the ventral tegmental area (VTA), which also results in the release of endocannabinoids from dopamine cell bodies. In this context, endocannabinoids are thought to regulate reward seeking by modulating dopamine signaling, although a direct link has never been demonstrated. To test this, we pharmacologically manipulated endocannabinoid neurotransmission in the VTA while measuring transient changes in dopamine concentration in the NAc during reward seeking. Disrupting endocannabinoid signaling dramatically reduced, whereas augmenting levels of the endocannabinoid 2-arachidonoylglycerol (2AG) increased, cue-evoked dopamine concentrations and reward seeking. These data suggest that 2AG in the VTA regulates reward seeking by sculpting ethologically relevant patterns of dopamine release during reward-directed behavior. Copyright © 2012 Elsevier Inc. All rights reserved.

Opposite modulation of brain stimulation reward by NMDA and AMPA receptors in the ventral tegmental area.

Directory of Open Access Journals (Sweden)

Charles eDucrot

2013-10-01

Full Text Available Previous studies have shown that blockade of ventral midbrain (VM glutamate N-Methyl-D-Aspartate (NMDA receptors induces reward, stimulates forward locomotion and enhances brain stimulation reward. Glutamate induces two types of excitatory response on VM neurons, a fast and short lasting depolarisation mediated by a-amino-3-hydroxy-5-methyl-4-isoxazole propionate (AMPA receptors and a longer lasting depolarization mediated by NMDA receptors. A role for the two glutamate receptors in modulation of VM neuronal activity is evidenced by the functional change in AMPA and NMDA synaptic responses that result from repeated exposure to reward. Since both receptors contribute to the action of glutamate on VM neuronal activity, we studied the effects of VM AMPA and NMDA receptor blockade on reward induced by electrical brain stimulation. Experiments were performed on rats trained to self-administer electrical pulses in the medial posterior mesencephalon. Reward thresholds were measured with the curve-shift paradigm before and for two hours after bilateral VM microinjections of the AMPA antagonist, NBQX (2,3,-Dioxo-6-nitro-1,2,3,4-tetrahydrobenzo(fquinoxaline-7-sulfonamide, 0, 80, and 800 pmol/0.5ul/side and of a single dose (0.825 nmol/0.5ul/side of the NMDA antagonist, PPPA (2R,4S-4-(3-Phosphonopropyl-2-piperidinecarboxylic acid. NBQX produced a dose-dependent increase in reward threshold with no significant change in maximum rate of responding. Whereas PPPA injected at the same VM sites produced a significant time dependent decrease in reward threshold and increase in maximum rate of responding. We found a negative correlation between the magnitude of the attenuation effect of NBQX and the enhancement effect of PPPA; moreover, NBQX and PPPA were most effective when injected respectively into the anterior and posterior VM. These results suggest that glutamate acts on different receptor sub-types, most likely located on different VM neurons, to modulate reward.

Sustainable Rest Area Design and Operations

Science.gov (United States)

2017-10-01

One way in which State Departments of Transportation (DOTs) can modernize their rest areas while reducing operations and maintenance costs is by incorporating sustainable practices into rest area design and operations. Sustainability practices that D...

Are some areas more equal than others? Socioeconomic inequality in potentially avoidable emergency hospital admissions within English local authority areas.

Science.gov (United States)

Sheringham, Jessica; Asaria, Miqdad; Barratt, Helen; Raine, Rosalind; Cookson, Richard

2017-04-01

Objectives Reducing health inequalities is an explicit goal of England's health system. Our aim was to compare the performance of English local administrative areas in reducing socioeconomic inequality in emergency hospital admissions for ambulatory care sensitive chronic conditions. Methods We used local authority area as a stable proxy for health and long-term care administrative geography between 2004/5 and 2011/12. We linked inpatient hospital activity, deprivation, primary care, and population data to small area neighbourhoods (typical population 1500) within administrative areas (typical population 250,000). We measured absolute inequality gradients nationally and within each administrative area using neighbourhood-level linear models of the relationship between national deprivation and age-sex-adjusted emergency admission rates. We assessed local equity performance by comparing local inequality against national inequality to identify areas significantly more or less equal than expected; evaluated stability over time; and identified where equity performance was steadily improving or worsening. We then examined associations between change in socioeconomic inequalities and change in within-area deprivation (gentrification). Finally, we used administrative area-level random and fixed effects models to examine the contribution of primary care to inequalities in admissions. Results Data on 316 administrative areas were included in the analysis. Local inequalities were fairly stable between consecutive years, but 32 areas (10%) showed steadily improving or worsening equity. In the 21 improving areas, the gap between most and least deprived fell by 3.9 admissions per 1000 (six times the fall nationally) between 2004/5 and 2011/12, while in the 11 areas worsening, the gap widened by 2.4. There was no indication that measured improvements in local equity were an artefact of gentrification or that changes in primary care supply or quality contributed to changes in

Translational control by eIF2α phosphorylation regulates vulnerability to the synaptic and behavioral effects of cocaine

Science.gov (United States)

Huang, Wei; Placzek, Andon N; Viana Di Prisco, Gonzalo; Khatiwada, Sanjeev; Sidrauski, Carmela; Krnjević, Krešimir; Walter, Peter; Dani, John A; Costa-Mattioli, Mauro

2016-01-01

Adolescents are especially prone to drug addiction, but the underlying biological basis of their increased vulnerability remains unknown. We reveal that translational control by phosphorylation of the translation initiation factor eIF2α (p-eIF2α) accounts for adolescent hypersensitivity to cocaine. In adolescent (but not adult) mice, a low dose of cocaine reduced p-eIF2α in the ventral tegmental area (VTA), potentiated synaptic inputs to VTA dopaminergic neurons, and induced drug-reinforced behavior. Like adolescents, adult mice with reduced p-eIF2α-mediated translational control were more susceptible to cocaine-induced synaptic potentiation and behavior. Conversely, like adults, adolescent mice with increased p-eIF2α became more resistant to cocaine's effects. Accordingly, metabotropic glutamate receptor-mediated long-term depression (mGluR-LTD)—whose disruption is postulated to increase vulnerability to drug addiction—was impaired in both adolescent mice and adult mice with reduced p-eIF2α mediated translation. Thus, during addiction, cocaine hijacks translational control by p-eIF2α, initiating synaptic potentiation and addiction-related behaviors. These insights may hold promise for new treatments for addiction. DOI: http://dx.doi.org/10.7554/eLife.12052.001 PMID:26928234

Blind inlets: Conservation practices to reduce herbicide losses from closed depressional areas

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Pesticides are designed to benefit agricultural production and may inadvertently affect water quality if environmental stewardship programs are not implemented. Closed depressional areas (potholes) are typical in the US Midwest and are usually drained with tile risers, however sediment and contamina...

Increased metabolic activity in the septum and habenula during stress is linked to subsequent expression of learned helplessness behavior.

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Mirrione, Martine M; Schulz, Daniela; Lapidus, Kyle A B; Zhang, Samuel; Goodman, Wayne; Henn, Fritz A

2014-01-01

Uncontrollable stress can have a profound effect on an organism's ability to respond effectively to future stressful situations. Behavior subsequent to uncontrollable stress can vary greatly between individuals, falling on a spectrum between healthy resilience and maladaptive learned helplessness. It is unclear whether dysfunctional brain activity during uncontrollable stress is associated with vulnerability to learned helplessness; therefore, we measured metabolic activity during uncontrollable stress that correlated with ensuing inability to escape future stressors. We took advantage of small animal positron emission tomography (PET) and 2-deoxy-2[(18)F]fluoro-D-glucose ((18)FDG) to probe in vivo metabolic activity in wild type Sprague Dawley rats during uncontrollable, inescapable, unpredictable foot-shock stress, and subsequently tested the animals response to controllable, escapable, predictable foot-shock stress. When we correlated metabolic activity during the uncontrollable stress with consequent behavioral outcomes, we found that the degree to which animals failed to escape the foot-shock correlated with increased metabolic activity in the lateral septum and habenula. When used a seed region, metabolic activity in the habenula correlated with activity in the lateral septum, hypothalamus, medial thalamus, mammillary nuclei, ventral tegmental area, central gray, interpeduncular nuclei, periaqueductal gray, dorsal raphe, and rostromedial tegmental nucleus, caudal linear raphe, and subiculum transition area. Furthermore, the lateral septum correlated with metabolic activity in the preoptic area, medial thalamus, habenula, interpeduncular nuclei, periaqueductal gray, dorsal raphe, and caudal linear raphe. Together, our data suggest a group of brain regions involved in sensitivity to uncontrollable stress involving the lateral septum and habenula.

Increased metabolic activity in the septum and habenula during stress is linked to subsequent expression of learned helplessness behavior

Directory of Open Access Journals (Sweden)

Martine M Mirrione

2014-02-01

Full Text Available Uncontrollable stress can have a profound effect on an organism’s ability to respond effectively to future stressful situations. Behavior subsequent to uncontrollable stress can vary greatly between individuals, falling on a spectrum between healthy resilience and maladaptive learned helplessness. It is unclear whether dysfunctional brain activity during uncontrollable stress is associated with vulnerability to learned helplessness; therefore, we measured metabolic activity during uncontrollable stress that correlated with ensuing inability to escape future stressors. We took advantage of small animal positron emission tomography (PET and 2-deoxy-2[18F]fluoro-D-glucose (18FDG to probe in vivo metabolic activity in wild type Sprague Dawley rats during uncontrollable, inescapable, unpredictable foot-shock stress, and subsequently tested the animals response to controllable, escapable, predictable foot-shock stress. When we correlated metabolic activity during the uncontrollable stress with consequent behavioral outcomes, we found that the degree to which animals failed to escape the foot-shock correlated with increased metabolic activity in the lateral septum and habenula. When used a seed region, metabolic activity in the habenula correlated with activity in the lateral septum, hypothalamus, medial thalamus, mammillary nuclei, ventral tegmental area, central gray, interpeduncular nuclei, periaqueductal gray, dorsal raphe, and rostromedial tegmental nucleus, caudal linear raphe, and subiculum transition area. Furthermore, the lateral septum correlated with metabolic activity in the preoptic area, medial thalamus, habenula, interpeduncular nuclei, periaqueductal gray, dorsal raphe, and caudal linear raphe. Together, our data suggest a group of brain regions involved in sensitivity to uncontrollable stress involving the lateral septum and habenula.

Directly Estimating Earthquake Rupture Area using Second Moments to Reduce the Uncertainty in Stress Drop

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McGuire, Jeffrey J.; Kaneko, Yoshihiro

2018-06-01

The key kinematic earthquake source parameters: rupture velocity, duration and area, shed light on earthquake dynamics, provide direct constraints on stress-drop, and have implications for seismic hazard. However, for moderate and small earthquakes, these parameters are usually poorly constrained due to limitations of the standard analysis methods. Numerical experiments by Kaneko and Shearer [2014,2015] demonstrated that standard spectral fitting techniques can lead to roughly 1 order of magnitude variation in stress-drop estimates that do not reflect the actual rupture properties even for simple crack models. We utilize these models to explore an alternative approach where we estimate the rupture area directly. For the suite of models, the area averaged static stress drop is nearly constant for models with the same underlying friction law, yet corner frequency based stress-drop estimates vary by a factor of 5-10 even for noise free data. Alternatively, we simulated inversions for the rupture area as parameterized by the second moments of the slip distribution. A natural estimate for the rupture area derived from the second moments is A=πLcWc, where Lc and Wc are the characteristic rupture length and width. This definition yields estimates of stress drop that vary by only 10% between the models but are slightly larger than the true area-averaged values. We simulate inversions for the second moments for the various models and find that the area can be estimated well when there are at least 15 available measurements of apparent duration at a variety of take-off angles. The improvement compared to azimuthally-averaged corner-frequency based approaches results from the second moments accounting for directivity and removing the assumption of a circular rupture area, both of which bias the standard approach. We also develop a new method that determines the minimum and maximum values of rupture area that are consistent with a particular dataset at the 95% confidence

Mitochondrial Respiration Is Reduced in Atherosclerosis, Promoting Necrotic Core Formation and Reducing Relative Fibrous Cap Thickness.

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Yu, Emma P K; Reinhold, Johannes; Yu, Haixiang; Starks, Lakshi; Uryga, Anna K; Foote, Kirsty; Finigan, Alison; Figg, Nichola; Pung, Yuh-Fen; Logan, Angela; Murphy, Michael P; Bennett, Martin

2017-12-01

Mitochondrial DNA (mtDNA) damage is present in murine and human atherosclerotic plaques. However, whether endogenous levels of mtDNA damage are sufficient to cause mitochondrial dysfunction and whether decreasing mtDNA damage and improving mitochondrial respiration affects plaque burden or composition are unclear. We examined mitochondrial respiration in human atherosclerotic plaques and whether augmenting mitochondrial respiration affects atherogenesis. Human atherosclerotic plaques showed marked mitochondrial dysfunction, manifested as reduced mtDNA copy number and oxygen consumption rate in fibrous cap and core regions. Vascular smooth muscle cells derived from plaques showed impaired mitochondrial respiration, reduced complex I expression, and increased mitophagy, which was induced by oxidized low-density lipoprotein. Apolipoprotein E-deficient (ApoE -/- ) mice showed decreased mtDNA integrity and mitochondrial respiration, associated with increased mitochondrial reactive oxygen species. To determine whether alleviating mtDNA damage and increasing mitochondrial respiration affects atherogenesis, we studied ApoE -/- mice overexpressing the mitochondrial helicase Twinkle (Tw + /ApoE -/- ). Tw + /ApoE -/- mice showed increased mtDNA integrity, copy number, respiratory complex abundance, and respiration. Tw + /ApoE -/- mice had decreased necrotic core and increased fibrous cap areas, and Tw + /ApoE -/- bone marrow transplantation also reduced core areas. Twinkle increased vascular smooth muscle cell mtDNA integrity and respiration. Twinkle also promoted vascular smooth muscle cell proliferation and protected both vascular smooth muscle cells and macrophages from oxidative stress-induced apoptosis. Endogenous mtDNA damage in mouse and human atherosclerosis is associated with significantly reduced mitochondrial respiration. Reducing mtDNA damage and increasing mitochondrial respiration decrease necrotic core and increase fibrous cap areas independently of changes in

Key factors leading to reduced recruitment and retention of health professionals in remote areas of Ghana: a qualitative study and proposed policy solutions

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Dzodzomenyo Mawuli

2011-05-01

Full Text Available Abstract Background The ability of many countries to achieve national health goals such as the Millennium Development Goals remains hindered by inadequate and poorly distributed health personnel, including doctors. The distribution of doctors in Ghana is highly skewed, with a majority serving in two major metropolitan areas (Accra and Kumasi, and inadequate numbers in remote and rural districts. Recent policies increasing health worker salaries have reduced migration of doctors out of Ghana, but made little difference to distribution within the country. This qualitative study was undertaken to understand how practicing doctors and medical leaders in Ghana describe the key factors reducing recruitment and retention of health professionals into remote areas, and to document their proposed policy solutions. Methods In-depth interviews were carried out with 84 doctors and medical leaders, including 17 regional medical directors and deputy directors from across Ghana, and 67 doctors currently practicing in 3 regions (Greater Accra, Brong Ahafo, and Upper West; these 3 regions were chosen to represent progressively more remote distances from the capital of Accra. Results and discussion All participants felt that rural postings must have special career or monetary incentives given the loss of locum (i.e. moonlighting income, the higher workload, and professional isolation of remote assignments. Career 'death' and prolonged rural appointments were a common fear, and proposed policy solutions focused considerably on career incentives, such as guaranteed promotion or a study opportunity after some fixed term of service in a remote or hardship area. There was considerable stress placed on the need for rural doctors to have periodic contact with mentors through rural rotation of specialists, or remote learning centers, and reliable terms of appointment with fixed end-points. Also raised, but given less emphasis, were concerns about the adequacy of clinical

Chronic social stress induces peripheral and central immune activation, blunted mesolimbic dopamine function, and reduced reward-directed behaviour in mice

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Giorgio Bergamini

2018-02-01

Full Text Available Psychosocial stress is a major risk factor for depression, stress leads to peripheral and central immune activation, immune activation is associated with blunted dopamine (DA neural function, DA function underlies reward interest, and reduced reward interest is a core symptom of depression. These states might be inter-independent in a complex causal pathway. Whilst animal-model evidence exists for some specific steps in the pathway, there is currently no animal model in which it has been demonstrated that social stress leads to each of these immune, neural and behavioural states. Such a model would provide important existential evidence for the complex pathway and would enable the study of causality and mediating mechanisms at specific steps in the pathway. Therefore, in the present mouse study we investigated for effects of 15-day resident-intruder chronic social stress (CSS on each of these states. Relative to controls, CSS mice exhibited higher spleen levels of granulocytes, inflammatory monocytes and T helper 17 cells; plasma levels of inducible nitric oxide synthase; and liver expression of genes encoding kynurenine pathway enzymes. CSS led in the ventral tegmental area to higher levels of kynurenine and the microglia markers Iba1 and Cd11b and higher binding activity of DA D1 receptor; and in the nucleus accumbens (NAcc to higher kynurenine, lower DA turnover and lower c-fos expression. Pharmacological challenge with DA reuptake inhibitor identified attenuation of DA stimulatory effects on locomotor activity and NAcc c-fos expression in CSS mice. In behavioural tests of operant responding for sucrose reward validated as sensitive assays for NAcc DA function, CSS mice exhibited less reward-directed behaviour. Therefore, this mouse study demonstrates that a chronic social stressor leads to changes in each of the immune, neural and behavioural states proposed to mediate between stress and disruption of DA-dependent reward processing. The

Urban Greening Bay Area

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Information about the San Francisco Bay Water Quality Project (SFBWQP) Urban Greening Bay Area, a large-scale effort to re-envision urban landscapes to include green infrastructure (GI) making communities more livable and reducing stormwater runoff.

The role of gamma-band activity in the representation of faces: reduced activity in the fusiform face area in congenital prosopagnosia.

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Christian Dobel

2011-05-01

Full Text Available Congenital prosopagnosia (CP describes an impairment in face processing that is presumably present from birth. The neuronal correlates of this dysfunction are still under debate. In the current paper, we investigate high-frequent oscillatory activity in response to faces in persons with CP. Such neuronal activity is thought to reflect higher-level representations for faces.Source localization of induced Gamma-Band Responses (iGBR measured by magnetoencephalography (MEG was used to establish the origin of oscillatory activity in response to famous and unknown faces which were presented in upright and inverted orientation. Persons suffering from congenital prosopagnosia (CP were compared to matched controls.Corroborating earlier research, both groups revealed amplified iGBR in response to upright compared to inverted faces predominately in a time interval between 170 and 330 ms and in a frequency range from 50-100 Hz. Oscillatory activity upon known faces was smaller in comparison to unknown faces, suggesting a "sharpening" effect reflecting more efficient processing for familiar stimuli. These effects were seen in a wide cortical network encompassing temporal and parietal areas involved in the disambiguation of homogenous stimuli such as faces, and in the retrieval of semantic information. Importantly, participants suffering from CP displayed a strongly reduced iGBR in the left fusiform area compared to control participants.In sum, these data stress the crucial role of oscillatory activity for face representation and demonstrate the involvement of a distributed occipito-temporo-parietal network in generating iGBR. This study also provides the first evidence that persons suffering from an agnosia actually display reduced gamma band activity. Finally, the results argue strongly against the view that oscillatory activity is a mere epiphenomenon brought fourth by rapid eye-movements (micro saccades.

Increase in vastus medialis cross-sectional area is associated with reduced pain, cartilage loss, and joint replacement risk in knee osteoarthritis.

Science.gov (United States)

Wang, Yuanyuan; Wluka, Anita E; Berry, Patricia A; Siew, Terence; Teichtahl, Andrew J; Urquhart, Donna M; Lloyd, David G; Jones, Graeme; Cicuttini, Flavia M

2012-12-01

Although there is evidence for a beneficial effect of increased quadriceps strength on knee symptoms, the effect on knee structure is unclear. We undertook this study to examine the relationship between change in vastus medialis cross-sectional area (CSA) and knee pain, tibial cartilage volume, and risk of knee replacement in subjects with symptomatic knee osteoarthritis (OA). One hundred seventeen subjects with symptomatic knee OA underwent magnetic resonance imaging of the knee at baseline and at 2 and 4.5 years. Vastus medialis CSA was measured at baseline and at 2 years. Tibial cartilage volume was measured at baseline and at 2 and 4.5 years. Knee pain was assessed by the Western Ontario and McMaster Universities Osteoarthritis Index at baseline and at 2 years. The frequency of knee joint replacement over 4 years was determined. Regression coefficients (B) and odds ratios were determined along with 95% confidence intervals (95% CIs). After adjusting for confounders, baseline vastus medialis CSA was inversely associated with current knee pain (r = -0.16, P = 0.04) and with medial tibial cartilage volume loss from baseline to 2 years (B coefficient -10.9 [95% CI -19.5, -2.3]), but not with baseline tibial cartilage volume. In addition, an increase in vastus medialis CSA from baseline to 2 years was associated with reduced knee pain over the same time period (r = 0.24, P = 0.007), reduced medial tibial cartilage loss from 2 to 4.5 years (B coefficient -16.8 [95% CI -28.9, -4.6]), and reduced risk of knee replacement over 4 years (odds ratio 0.61 [95% CI 0.40, 0.94]). In a population of patients with symptomatic knee OA, increased vastus medialis size was associated with reduced knee pain and beneficial structural changes at the knee, suggesting that management of knee pain and optimizing vastus medialis size are important in reducing OA progression and subsequent knee replacement. Copyright © 2012 by the American College of Rheumatology.

Opportunities for reducing greenhouse gas, energy use, and electricity use in the Greater Toronto area

Energy Technology Data Exchange (ETDEWEB)

NONE

2006-02-16

The Clean Air Partnership (CAP) was interested in scanning and prioritizing energy efficiency opportunities to reduce energy use and the associated greenhouse gas emissions in the greater Toronto area (GTA). A study was conducted to scope out the most promising program directions for the GTA should government funding become available to launch the initiative, based on the relative technical potential of energy efficiency (and some fuel substitution) measures in the targeted sectors. A report to the Ontario Power Authority (OPA) focused on the residential and institutional sectors. These included new and existing residential buildings, condominiums and single-family homes, with special detail provided on appliances and central air conditioning; as well as municipal, university, school, and hospital buildings, with special attention towards measures to make street and traffic signal lighting more energy efficient. This letter provided a summary of findings. Next steps were also presented. It was recommended that three market transformation initiatives be designed and implemented to realize the technical potential for reductions in peak electricity and carbon dioxide emissions reductions. These three programs were discussed with reference to the energy efficient lighting collaborative; a green loan program for new homes and condominiums; and a community residential CDM program. A market transformation framework was also presented. It addressed the five key steps in the movement of a product from the manufacturer to the end user, namely availability; awareness; accessibility; affordability; and acceptance. 1 tab., 3 figs.

Effective Area and Charge Density of Iridium Oxide Neural Electrodes

International Nuclear Information System (INIS)

Harris, Alexander R.; Paolini, Antonio G.; Wallace, Gordon G.

2017-01-01

The effective electrode area and charge density of iridium metal and anodically activated iridium has been measured by optical and electrochemical techniques. The degree of electrode activation could be assessed by changes in electrode colour. The reduction charge, activation charge, number of activation pulses and charge density were all strongly correlated. Activated iridium showed slow electron transfer kinetics for reduction of a dissolved redox species. At fast voltammetric scan rates the linear diffusion electroactive area was unaffected by iridium activation. At slow voltammetric scan rates, the steady state diffusion electroactive area was reduced by iridium activation. The steady state current was consistent with a ring electrode geometry, with lateral resistance reducing the electrode area. Slow electron transfer on activated iridium would require a larger overpotential to reduce or oxidise dissolved species in tissue, limiting the electrodes charge capacity but also reducing the likelihood of generating toxic species in vivo.

Defective functional connectivity between posterior hypothalamus and regions of the diencephalic-mesencephalic junction in chronic cluster headache.

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Ferraro, Stefania; Nigri, Anna; Bruzzone, Maria Grazia; Brivio, Luca; Proietti Cecchini, Alberto; Verri, Mattia; Chiapparini, Luisa; Leone, Massimo

2018-01-01

Objective We tested the hypothesis of a defective functional connectivity between the posterior hypothalamus and diencephalic-mesencephalic regions in chronic cluster headache based on: a) clinical and neuro-endocrinological findings in cluster headache patients; b) neuroimaging findings during cluster headache attacks; c) neuroimaging findings in drug-refractory chronic cluster headache patients improved after successful deep brain stimulation. Methods Resting state functional magnetic resonance imaging, associated with a seed-based approach, was employed to investigate the functional connectivity of the posterior hypothalamus in chronic cluster headache patients (n = 17) compared to age and sex-matched healthy subjects (n = 16). Random-effect analyses were performed to study differences between patients and controls in ipsilateral and contralateral-to-the-pain posterior hypothalamus functional connectivity. Results Cluster headache patients showed an increased functional connectivity between the ipsilateral posterior hypothalamus and a number of diencephalic-mesencephalic structures, comprising ventral tegmental area, dorsal nuclei of raphe, and bilateral substantia nigra, sub-thalamic nucleus, and red nucleus ( p cluster headache patients mainly involves structures that are part of (i.e. ventral tegmental area, substantia nigra) or modulate (dorsal nuclei of raphe, sub-thalamic nucleus) the midbrain dopaminergic systems. The midbrain dopaminergic systems could play a role in cluster headache pathophysiology and in particular in the chronicization process. Future studies are needed to better clarify if this finding is specific to cluster headache or if it represents an unspecific response to chronic pain.

Contour adaptation reduces the spreading of edge induced colors.

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Coia, Andrew J; Crognale, Michael A

2017-04-25

Brief exposure to flickering achromatic outlines of an area causes a reduction in the brightness contrast of the surface inside the area. This contour adaptation to achromatic contours does not reduce surface contrast when the surface is chromatic (the saturation or colorimetric purity of the surface is maintained). In addition to reducing the brightness of physical luminance contrast, contour adaptation also reduces (or even reverses) the illusory brightness contrast seen in the Craik-O'Brien-Cornsweet illusion, in which two physically identical grey areas appear different brightness because of a sharp luminance edge separating them. Chromatic color spreading illusions also occur with chromatic inducing edges, and an unanswered question is whether contour adaptation can reduce the perceived contrast of illusory color spreading from edges, even though it cannot reduce the perceived contrast of physical surface color. The current studies use a color spreading illusion known as the watercolor effect in order to test whether illusory color spreading is affected by contour adaptation. The general findings of physical achromatic contrast being reduced and chromatic contrast being robust to contour adaptation were replicated. However, both illusory brightness and color were reduced by contour adaptation, even when the illusion edges only differed in chromatic contrast with each other and the background. Additional studies adapting to chromatic contours showed opposite effects on illusory color contrast than achromatic adaptation. Copyright © 2017 Elsevier Ltd. All rights reserved.

Risk assessment and management of brucellosis in the southern greater Yellowstone area (II): Cost-benefit analysis of reducing elk brucellosis prevalence.

Science.gov (United States)

Boroff, Kari; Kauffman, Mandy; Peck, Dannele; Maichak, Eric; Scurlock, Brandon; Schumaker, Brant

2016-11-01

Recent cases of bovine brucellosis (Brucella abortus) in cattle (Bos taurus) and domestic bison (Bison bison) of the southern Greater Yellowstone Area (SGYA) have been traced back to free-ranging elk (Cervus elaphus). Several management activities have been implemented to reduce brucellosis seroprevalence in elk, including test-and-slaughter, low-density feeding at elk winter feedgrounds, and elk vaccination. It is unclear which of these activities are most cost-effective at reducing the risk of elk transmitting brucellosis to cattle. In a companion paper, a stochastic risk model was used to translate a reduction in elk seroprevalence to a reduction in the risk of transmission to cattle. Here, we use those results to estimate the expected economic benefits and costs of reducing seroprevalence in elk using three different management activities: vaccination of elk with Brucella strain 19 (S19), low-density feeding of elk, and elk test-and-slaughter. Results indicate that the three elk management activities yield negative expected net benefits, ranging from -$2983 per year for low-density feeding to -$595,471 per year for test-and-slaughter. Society's risk preferences will determine whether strategies that generate small negative net benefit, such as low-density feeding, are worth implementing. However, activities with large negative net benefits, such as test-and-slaughter and S19 vaccination, are unlikely to be economically worthwhile. Given uncertainty about various model parameters, we identify some circumstances in which individual management activities might generate positive expected net benefit. Copyright © 2016 Elsevier B.V. All rights reserved.

Novel Omega-3 Fatty Acid Epoxygenase Metabolite Reduces Kidney Fibrosis

Science.gov (United States)

Sharma, Amit; Khan, Md. Abdul Hye; Levick, Scott P.; Lee, Kin Sing Stephen; Hammock, Bruce D.; Imig, John D.

2016-01-01

Cytochrome P450 (CYP) monooxygenases epoxidize the omega-3 polyunsaturated fatty acid (PUFA) docosahexaenoic acid into novel epoxydocosapentaenoic acids (EDPs) that have multiple biological actions. The present study determined the ability of the most abundant EDP regioisomer, 19,20-EDP to reduce kidney injury in an experimental unilateral ureteral obstruction (UUO) renal fibrosis mouse model. Mice with UUO developed kidney tubular injury and interstitial fibrosis. UUO mice had elevated kidney hydroxyproline content and five-times greater collagen positive fibrotic area than sham control mice. 19,20-EDP treatment to UUO mice for 10 days reduced renal fibrosis with a 40%–50% reduction in collagen positive area and hydroxyproline content. There was a six-fold increase in kidney α-smooth muscle actin (α-SMA) positive area in UUO mice compared to sham control mice, and 19,20-EDP treatment to UUO mice decreased α-SMA immunopositive area by 60%. UUO mice demonstrated renal epithelial-to-mesenchymal transition (EMT) with reduced expression of the epithelial marker E-cadherin and elevated expression of multiple mesenchymal markers (FSP-1, α-SMA, and desmin). Interestingly, 19,20-EDP treatment reduced renal EMT in UUO by decreasing mesenchymal and increasing epithelial marker expression. Overall, we demonstrate that a novel omega-3 fatty acid metabolite 19,20-EDP, prevents UUO-induced renal fibrosis in mice by reducing renal EMT. PMID:27213332

New Energy Efficient Housing Has Reduced Carbon Footprints in Outer but Not in Inner Urban Areas.

Science.gov (United States)

Ottelin, Juudit; Heinonen, Jukka; Junnila, Seppo

2015-08-18

Avoiding urban sprawl and increasing density are often considered as effective means to mitigate climate change through urban planning. However, there have been rapid technological changes in the fields of housing energy and private driving, and the development is continuing. In this study, we analyze the carbon footprints of the residents living in new housing in different urban forms in Finland. We compare the new housing to existing housing stock. In all areas, the emissions from housing energy were significantly lower in new buildings. However, in the inner urban areas the high level of consumption, mostly due to higher affluence, reverse the gains of energy efficient new housing. The smallest carbon footprints were found in newly built outer and peri-urban areas, also when income level differences were taken into account. Rather than strengthening the juxtaposition of urban and suburban areas, we suggest that it would be smarter to recognize the strengths and weaknesses of both modes of living and develop a more systemic strategy that would result in greater sustainability in both areas. Since such strategy does not exist yet, it should be researched and practically developed. It would be beneficial to focus on area specific mitigation measures.

CB1-Dependent Long-Term Depression in Ventral Tegmental Area GABA Neurons: A Novel Target for Marijuana.

Science.gov (United States)

Friend, Lindsey; Weed, Jared; Sandoval, Philip; Nufer, Teresa; Ostlund, Isaac; Edwards, Jeffrey G

2017-11-08

The VTA is necessary for reward behavior with dopamine cells critically involved in reward signaling. Dopamine cells in turn are innervated and regulated by neighboring inhibitory GABA cells. Using whole-cell electrophysiology in juvenile-adolescent GAD67-GFP male mice, we examined excitatory plasticity in fluorescent VTA GABA cells. A novel CB1-dependent LTD was induced in GABA cells that was dependent on metabotropic glutamate receptor 5, and cannabinoid receptor 1 (CB1). LTD was absent in CB1 knock-out mice but preserved in heterozygous littermates. Bath applied Δ 9 -tetrahydrocannabinol depressed GABA cell activity, therefore downstream dopamine cells will be disinhibited; and thus, this could potentially result in increased reward. Chronic injections of Δ 9 -tetrahydrocannabinol occluded LTD compared with vehicle injections; however, a single exposure was insufficient to do so. As synaptic modifications by drugs of abuse are often tied to addiction, these data suggest a possible mechanism for the addictive effects of Δ 9 -tetrahydrocannabinol in juvenile-adolescents, by potentially altering reward behavioral outcomes. SIGNIFICANCE STATEMENT The present study identifies a novel form of glutamatergic synaptic plasticity in VTA GABA neurons, a currently understudied cell type that is critical for the brain's reward circuit, and how Δ 9 -tetrahydrocannabinol occludes this plasticity. This study specifically addresses a potential unifying mechanism whereby marijuana could exert rewarding and addictive/withdrawal effects. Marijuana use and legalization are a pressing issue for many states in the United States. Although marijuana is the most commonly abused illicit drug, the implications of legalized, widespread, or continued usage are speculative. This study in juvenile-adolescent aged mice identifies a novel form of synaptic plasticity in VTA GABA cells, and the synaptic remodeling that can occur after Δ 9 -tetrahydrocannabinol use. Copyright © 2017 the authors 0270-6474/17/3710943-12$15.00/0.

Bisphenol S (BPS) Alters Maternal Behavior and Brain in Mice Exposed During Pregnancy/Lactation and Their Daughters.

Science.gov (United States)

Catanese, Mary C; Vandenberg, Laura N

2017-03-01

Estrogenic endocrine disrupting chemicals have been shown to disrupt maternal behavior in rodents. We investigated the effects of an emerging xenoestrogen, bisphenol S (BPS), on maternal behavior and brain in CD-1 mice exposed during pregnancy and lactation (F0 generation) and in female offspring exposed during gestation and perinatal development (F1 generation). We observed different effects in F0 and F1 dams for a number of components of maternal behavior, including time on the nest, time spent on nest building, latency to retrieve pups, and latency to retrieve the entire litter. We also characterized expression of estrogen receptor α in the medial preoptic area (MPOA) and quantified tyrosine hydroxylase immunoreactive cells in the ventral tegmental area, 2 brain regions critical for maternal care. BPS-treated females in the F0 generation had a statistically significant increase in estrogen receptor α expression in the caudal subregion of the central MPOA in a dose-dependent manner. In contrast, there were no statistically significant effects of BPS on the MPOA in F1 dams or the ventral tegmental area in either generation. This work demonstrates that BPS affects maternal behavior and brain with outcomes depending on generation, dose, and postpartum period. Many studies examining effects of endocrine disrupting chemicals view the mother as a means by which offspring can be exposed during critical periods of development. Here, we demonstrate that pregnancy and lactation are vulnerable periods for the mother. We also show that developmental BPS exposure alters maternal behavior later in adulthood. Both findings have potential public health implications. Copyright © 2017 by the Endocrine Society.

MR imaging findings of hypertrophic olivary degeneration

Energy Technology Data Exchange (ETDEWEB)

Kim, Do Joong; Jeon, Pyung; Kim, Dong Ik [Yonsei Univ. College of Medicine, Seoul (Korea, Republic of)

1997-06-01

To describe the magnetic resonance (MR) imaging findings of hypertrophic olivary degeneration (HOD) MR images of seven patients with HOD were retrospectively reviewed. Two were women and five were men, and they were aged between 48 and 65 (mean 58) years. Imaging examinations were performed with a 1.5-T unit, and the findings were used to evaluate the size and signal intensity of olivary lesions. The time interval from hemorrhagic ictus to MR imaging was between two and 30 months. Follow-up examinations were performed in two patients. All four patients with hemorrhages involving the central tegmental tract in the pons or midbrain showed ipsilateral HOD. Among these four, bilateral HOD was seen in one patient with hemorrhage involving the bilateral central tegmental tract, and in another with tegmental hemorrhage extending to the ipsilateral superior cerebellar peduncle. One patient with cerebellar hemorrhage involving the dentate nucleus had contralateral HOD. Two patients with multiple hemorrhages involving both the pons and cerebellum showed bilateral HOD. Axial MR images showed mild enlargement of the involved olivary mucleus, with high signal intensity on both proton density and T2 weighted images. There was no apparent enhancement on postcontrast T1-weighted images. MR imaging can clearly distinguish secondary olivary degeneration from underlying pathology involving the central tegmental tract in the pons or midbrain and cerebellum. These olivary abnormalities should not, however, be mistaken for primary medullary lesions.

MR imaging findings of hypertrophic olivary degeneration

International Nuclear Information System (INIS)

Kim, Do Joong; Jeon, Pyung; Kim, Dong Ik

1997-01-01

To describe the magnetic resonance (MR) imaging findings of hypertrophic olivary degeneration (HOD) MR images of seven patients with HOD were retrospectively reviewed. Two were women and five were men, and they were aged between 48 and 65 (mean 58) years. Imaging examinations were performed with a 1.5-T unit, and the findings were used to evaluate the size and signal intensity of olivary lesions. The time interval from hemorrhagic ictus to MR imaging was between two and 30 months. Follow-up examinations were performed in two patients. All four patients with hemorrhages involving the central tegmental tract in the pons or midbrain showed ipsilateral HOD. Among these four, bilateral HOD was seen in one patient with hemorrhage involving the bilateral central tegmental tract, and in another with tegmental hemorrhage extending to the ipsilateral superior cerebellar peduncle. One patient with cerebellar hemorrhage involving the dentate nucleus had contralateral HOD. Two patients with multiple hemorrhages involving both the pons and cerebellum showed bilateral HOD. Axial MR images showed mild enlargement of the involved olivary mucleus, with high signal intensity on both proton density and T2 weighted images. There was no apparent enhancement on postcontrast T1-weighted images. MR imaging can clearly distinguish secondary olivary degeneration from underlying pathology involving the central tegmental tract in the pons or midbrain and cerebellum. These olivary abnormalities should not, however, be mistaken for primary medullary lesions

Reduced embodied simulation in psychopathy.

Science.gov (United States)

Mier, Daniela; Haddad, Leila; Diers, Kersten; Dressing, Harald; Meyer-Lindenberg, Andreas; Kirsch, Peter

2014-08-01

Psychopathy is characterized by severe deficits in emotion processing and empathy. These emotional deficits might not only affect the feeling of own emotions, but also the understanding of others' emotional and mental states. The present study aims on identifying the neurobiological correlates of social-cognitive related alterations in psychopathy. We applied a social-cognitive paradigm for the investigation of face processing, emotion recognition, and affective Theory of Mind (ToM) to 11 imprisoned psychopaths and 18 healthy controls. Functional magnetic resonance imaging was used to measure task-related brain activation. While showing no overall behavioural deficit, psychopathy was associated with altered brain activation. Psychopaths had reduced fusiform activation related to face processing. Related to affective ToM, psychopaths had hypoactivation in amygdala, inferior prefrontal gyrus and superior temporal sulcus, areas associated with embodied simulation of emotions and intentions. Furthermore, psychopaths lacked connectivity between superior temporal sulcus and amygdala during affective ToM. These results replicate findings of alterations in basal face processing in psychopathy. In addition, they provide evidence for reduced embodied simulation in psychopathy in concert with a lack of communication between motor areas and amygdala which might provide the neural substrate of reduced feeling with others during social cognition.

Reducing contact resistance in graphene devices through contact area patterning.

Science.gov (United States)

Smith, Joshua T; Franklin, Aaron D; Farmer, Damon B; Dimitrakopoulos, Christos D

2013-04-23

Performance of graphene electronics is limited by contact resistance associated with the metal-graphene (M-G) interface, where unique transport challenges arise as carriers are injected from a 3D metal into a 2D-graphene sheet. In this work, enhanced carrier injection is experimentally achieved in graphene devices by forming cuts in the graphene within the contact regions. These cuts are oriented normal to the channel and facilitate bonding between the contact metal and carbon atoms at the graphene cut edges, reproducibly maximizing "edge-contacted" injection. Despite the reduction in M-G contact area caused by these cuts, we find that a 32% reduction in contact resistance results in Cu-contacted, two-terminal devices, while a 22% reduction is achieved for top-gated graphene transistors with Pd contacts as compared to conventionally fabricated devices. The crucial role of contact annealing to facilitate this improvement is also elucidated. This simple approach provides a reliable and reproducible means of lowering contact resistance in graphene devices to bolster performance. Importantly, this enhancement requires no additional processing steps.

Effects of reduced soil functionality in European vineyards

Science.gov (United States)

Costantini, Edoardo; Priori, Simone; Akca, Ehran; Castaldini, Maurizio; D'Avino, Lorenzo; Fulchin, Emma; Gagnarli, Elena; Giffard, Brice; Erdem Kiraz, Mehmet; Lagomarsino, Alessandra; Landi, Silvia; Pellegrini, Sergio; Perria, Rita; Puccioni, Sergio; Schroers, Hans-Josef; Tardaguila, Javier; Pelengić, Radojko; Simoni, Sauro; Storchi, Paolo; Tangolar, Semih

2017-04-01

Improper or excessive land preparation methods in vineyards before planting can have a considerable impact on soil functionality. They include excessive levelling and deep ploughing leading to disturbances of the natural contour of slopes and destruction, truncation and burial of soil horizons. Manipulations may significantly modify chemical, physical, biological and hydrological balance of soils. Problems that may arise from these interventions relate to the reduction of organic substances, enrichment of calcium carbonate and soluble salts, impacting development and health of grapevines. Reduced water retention capacity can lead to increased water stress during dry season, decreased water permeability and circulation of oxygen in the soil, increased runoff volume, surface erosion and landslide risk, reduced biodiversity and limitation of biochemical processes (organic matter mineralization, bioavailability of nutrients, etc.). Soil degradations can lead to the loss of soil functionality even after the planting as a result of accelerated erosion, compaction by agricultural vehicles, excessive loss of organic matter and nutrients, and the accumulation of heavy metals such as copper. In both conventional and organic vineyards, it is quite common to have areas with reduced soil functionality that have negative impact on vine health and grape production and quality. In the framework of the Core organic RESOLVE project, a study was conducted in organic vineyards showing areas with reduced and good soil functionality. Degraded soils resulted in significantly lower amounts of grapes. The chlorophyll index (SPAD) of the grapevine during veraison was significantly lower in areas of degraded soils compared with the situation in areas of the same vineyard with non-degraded soils. In general, causes of soil malfunctioning were related to a lower fertility, including reduced organic carbon, total nitrogen and cation exchange capacity, higher concentrations of carbonates, and

Sucralfate significantly reduces ciprofloxacin concentrations in serum.

OpenAIRE

Garrelts, J C; Godley, P J; Peterie, J D; Gerlach, E H; Yakshe, C C

1990-01-01

The effect of sucralfate on the bioavailability of ciprofloxacin was evaluated in eight healthy subjects utilizing a randomized, crossover design. The area under the concentration-time curve from 0 to 12 h was reduced from 8.8 to 1.1 micrograms.h/ml by sucralfate (P less than 0.005). Similarly, the maximum concentration of ciprofloxacin in serum was reduced from 2.0 to 0.2 micrograms/ml (P less than 0.005). We conclude that concurrent ingestion of sucralfate significantly reduces the concentr...

Pervasive competition between threat and reward in the brain.

Science.gov (United States)

Choi, Jong Moon; Padmala, Srikanth; Spechler, Philip; Pessoa, Luiz

2014-06-01

In the current functional MRI study, we investigated interactions between reward and threat processing. Visual cues at the start of each trial informed participants about the chance of winning monetary reward and/or receiving a mild aversive shock. We tested two competing hypothesis: according to the 'salience hypothesis', in the condition involving both reward and threat, enhanced activation would be observed because of increased salience; according to the 'competition hypothesis', the processing of reward and threat would trade-off against each other, leading to reduced activation. Analysis of skin conductance data during a delay phase revealed an interaction between reward and threat processing, such that the effect of reward was reduced during threat and the effect of threat was reduced during reward. Analysis of imaging data during the same task phase revealed interactions between reward and threat processing in several regions, including the midbrain/ventral tegmental area, caudate, putamen, bed nucleus of the stria terminalis, anterior insula, middle frontal gyrus and dorsal anterior cingulate cortex. Taken together, our findings reveal conditions during which reward and threat trade-off against each other across multiple sites. Such interactions are suggestive of competitive processes and may reflect the organization of opponent systems in the brain. © The Author (2013). Published by Oxford University Press. For Permissions, please email: journals.permissions@oup.com.

Role of music in morphine rewarding effects in mice using conditioned place preference method.

Science.gov (United States)

Tavakoli, Farnaz; Hoseini, Seyed Ebrahim; Mokhtari, Mokhtar; Vahdati, Akbar; Razmi, Nematollah; Vessal, Mahmood

2012-01-01

This research aims at studying the neuroendocrine effects of music on creating morphine dependence in mice using conditioned place preference (CPP). The mice treated with 10 mg/kg morphine subcutaneously, fast music and slow music. Morphine was used to create dependence. In order to recognize the morphine rewarding effects, CPP technique was used. In the conditioning stage that lasted for 8 days, different groups of mice, after receiving the treatment were randomly placed in compartment for 30 minutes. The post-conditioning stage included the fourth day, the ninth day, the 12th day and the 16th day. Comparing place preference between morphine group and the control group, a significant increase (pmusic group compared with morphine group alone. In addition morphine + alone in the rain music group demonstrated a significantly increased conditioned place preference (pmusic acts as a positive pleasant emotion increasing the dopaminergic activity in the Nucleus Accumbens (NAc) and Ventral Tegmental Area (VTA) and through associated learning mechanisms of reward-related behavior increases morphine addiction. However, taxi girl music may act as unpleasant experiences producing negative emotions and reducing morphine addiction.

The role of nucleus accumbens core/shell in sleep-wake regulation and their involvement in modafinil-induced arousal.

Directory of Open Access Journals (Sweden)

Mei-Hong Qiu

Full Text Available BACKGROUND: We have previously shown that modafinil promotes wakefulness via dopamine receptor D(1 and D(2 receptors; however, the locus where dopamine acts has not been identified. We proposed that the nucleus accumbens (NAc that receives the ventral tegmental area dopamine inputs play an important role not only in reward and addiction but also in sleep-wake cycle and in mediating modafinil-induced arousal. METHODOLOGY/PRINCIPAL FINDINGS: In the present study, we further explored the role of NAc in sleep-wake cycle and sleep homeostasis by ablating the NAc core and shell, respectively, and examined arousal response following modafinil administration. We found that discrete NAc core and shell lesions produced 26.5% and 17.4% increase in total wakefulness per day, respectively, with sleep fragmentation and a reduced sleep rebound after a 6-hr sleep deprivation compared to control. Finally, NAc core but not shell lesions eliminated arousal effects of modafinil. CONCLUSIONS/SIGNIFICANCE: These results indicate that the NAc regulates sleep-wake behavior and mediates arousal effects of the midbrain dopamine system and stimulant modafinil.

Leptin Suppresses the Rewarding Effects of Running via STAT3 Signaling in Dopamine Neurons.

Science.gov (United States)

Fernandes, Maria Fernanda A; Matthys, Dominique; Hryhorczuk, Cécile; Sharma, Sandeep; Mogra, Shabana; Alquier, Thierry; Fulton, Stephanie

2015-10-06

The adipose hormone leptin potently influences physical activity. Leptin can decrease locomotion and running, yet the mechanisms involved and the influence of leptin on the rewarding effects of running ("runner's high") are unknown. Leptin receptor (LepR) signaling involves activation of signal transducer and activator of transcription-3 (STAT3), including in dopamine neurons of the ventral tegmental area (VTA) that are essential for reward-relevant behavior. We found that mice lacking STAT3 in dopamine neurons exhibit greater voluntary running, an effect reversed by viral-mediated STAT3 restoration. STAT3 deletion increased the rewarding effects of running whereas intra-VTA leptin blocked it in a STAT3-dependent manner. Finally, STAT3 loss-of-function reduced mesolimbic dopamine overflow and function. Findings suggest that leptin influences the motivational effects of running via LepR-STAT3 modulation of dopamine tone. Falling leptin is hypothesized to increase stamina and the rewarding effects of running as an adaptive means to enhance the pursuit and procurement of food. Copyright © 2015 Elsevier Inc. All rights reserved.

Empathic concern drives costly altruism

Science.gov (United States)

FeldmanHall, Oriel; Dalgleish, Tim; Evans, Davy; Mobbs, Dean

2015-01-01

Why do we self-sacrifice to help others in distress? Two competing theories have emerged, one suggesting that prosocial behavior is primarily motivated by feelings of empathic other-oriented concern, the other that we help mainly because we are egoistically focused on reducing our own discomfort. Here we explore the relationship between costly altruism and these two sub-processes of empathy, specifically drawing on the caregiving model to test the theory that trait empathic concern (e.g. general tendency to have sympathy for another) and trait personal distress (e.g. predisposition to experiencing aversive arousal states) may differentially drive altruistic behavior. We find that trait empathic concern – and not trait personal distress – motivates costly altruism, and this relationship is supported by activity in the ventral tegmental area, caudate and subgenual anterior cingulate, key regions for promoting social attachment and caregiving. Together, this data helps identify the behavioral and neural mechanisms motivating costly altruism, while demonstrating that individual differences in empathic concern-related brain responses can predict real prosocial choice. PMID:25462694

The role of the habenula in drug addiction

Directory of Open Access Journals (Sweden)

Kenia Marisela Velasquez

2014-03-01

Full Text Available Interest in the habenula has greatly increased in recent years. The habenula is a small brain structure located posterior to the thalamus and adjacent to the third ventricle. Despite its small size, the habenula can be divided into medial (MHb and lateral (LHb nuclei that are anatomically and transcriptionally distinct. The habenula receives inputs from the limbic system and basal ganglia primarily via the stria medullaris. The fasciculus retroflexus is the primary habenular output from the habenula to the midbrain and governs release of glutamate onto gabaergic cells in the rostromedial tegmental nucleus (RMTg and onto the interpeduncular nucleus (IPN. The resulting GABA released from RMTg neurons inactivates dopaminergic cells in the ventral tegmental area (VTA/substantia nigra compacta (SNc. Through this process, the habenula controls dopamine levels in the striatum. Thus, the habenula plays a critical role in reward and reward-associated learning. The LHb also modulates serotonin levels and norepinephrine release, while the MHb modulates acetylcholine. The habenula is a critical crossroad that influences the brain’s response to pain, stress, anxiety, sleep, and reward. Dysfunction of the habenula has been linked to depression, schizophrenia, and the effects of drugs of abuse. This review focuses on the possible relationships between the habenula and drug abuse.

Inter-dependence not Over-dependence: Reducing Urban Transport Energy Dependence

Energy Technology Data Exchange (ETDEWEB)

Saunders, Michael James; Rodrigues da Silva, Antonio Nelson

2007-07-01

A major issue of concern in today's world is urban transport energy dependence and energy supply security. In an energy inter-dependent world, energy over-dependence brings risks to urban transport systems. Many urban areas are over-dependent on finite petroleum resources for transport. New technology and the development and integration of renewable resources into transport energy systems may reduce some of the current transport energy dependence of urban areas. However, the most effective means of reducing energy dependence is to first design urban areas for this condition. An urban policy framework is proposed that requires transport energy dependence to be measured and controlled in the urban development process. A new tool has been created for this purpose, the Transport Energy Specification (TES), which measures transport energy dependence of urban areas. This creates the possibility for cities to regulate urban development with respect to energy dependence. Trial assessments were performed in Germany, New Zealand and Brazil; initial analysis by transport and government professionals shows promise of this tool being included into urban policy. The TES combined with a regulatory framework has the potential to significantly reduce transport energy consumption and dependence in urban areas in the future. (auth)

Sex and age-dependent effects of a maternal junk food diet on the mu-opioid receptor in rat offspring.

Science.gov (United States)

Gugusheff, Jessica R; Bae, Sung Eun; Rao, Alexandra; Clarke, Iain J; Poston, Lucilla; Taylor, Paul D; Coen, Clive W; Muhlhausler, Beverly S

2016-03-15

Perinatal junk food exposure increases the preference for palatable diets in juvenile and adult rat offspring. Previous studies have implicated reduced sensitivity of the opioid pathway in the programming of food preferences; however it is not known when during development these changes in opioid signalling first emerge. This study aimed to determine the impact of a maternal junk food (JF) diet on mu-opioid receptor (MuR) expression and ligand binding in two key regions of the reward pathway, the nucleus accumbens (NAc) and the ventral tegmental area (VTA) in rats during the early suckling (postnatal day (PND) 1 and 7) and late suckling/early post-weaning (PND 21 and 28) periods. Female rats were fed either a JF or a control diet for two weeks prior to mating and throughout pregnancy and lactation. MuR expression in the VTA was significantly reduced in female JF offspring on PND 21 and 28 (by 32% and 57% respectively, Pjunk food exposure on MuR mRNA expression or binding were detected at these time points in male offspring. These findings provide evidence that the opioid signalling system is a target of developmental programming by the end of the third postnatal week in females, but not in males. Copyright © 2015 Elsevier B.V. All rights reserved.

Oxytocin receptor antagonist treatments alter levels of attachment to mothers and central dopamine activity in pre-weaning mandarin vole pups.

Science.gov (United States)

He, Zhixiong; Hou, Wenjuan; Hao, Xin; Dong, Na; Du, Peirong; Yuan, Wei; Yang, Jinfeng; Jia, Rui; Tai, Fadao

2017-10-01

Oxytocin (OT) is known to be important in mother-infant bonding. Although the relationship between OT and filial attachment behavior has been studied in a few mammalian species, the effects on infant social behavior have received little attention in monogamous species. The present study examined the effects of OT receptor antagonist (OTA) treatment on attachment behavior and central dopamine (DA) activity in male and female pre-weaning mandarin voles (Microtus mandarinus). Our data showed that OTA treatments decreased the attachment behavior of pups to mothers, measured using preference tests at postnatal day 14, 16, 18 and 20. OTA treatments reduced serum OT concentration in pre-weaning pups and decreased tyrosine hydroxylase (TH) levels in the ventral tegmental area (VTA), indicating a decrease in central DA activity. In male and female pups, OTA reduced DA levels, DA 1-type receptor (D1R) and DA 2-type receptor (D2R) protein expression in the nucleus accumbens (NAcc). Our results indicate that OTA treatment inhibits the attachment of pre-weaning pups to mothers. This inhibition is possibly associated with central DA activity and levels of two types of dopamine receptor in the NAcc. Copyright © 2017 Elsevier Ltd. All rights reserved.

Effects of Electroacupuncture on Methamphetamine-Induced Behavioral Changes in Mice

Directory of Open Access Journals (Sweden)

Tsung-Jung Ho

2017-01-01

Full Text Available Methamphetamine (METH is a major drug of abuse worldwide, and no efficient therapeutic strategies for treating METH addiction are currently available. Continuous METH use can cause behavioral upregulation or psychosis. The dopaminergic pathways, particularly the neural circuitry from the ventral tegmental area to the nucleus accumbens (NAc, have a critical role in this behavioral stage. Acupuncture has been used for treating diseases in China for more than 2000 years. According to a World Health Organization report, acupuncture can be used to treat several functional disorders, including substance abuse. In addition, acupuncture is effective against opioids addiction. In this study, we used electroacupuncture (EA for treating METH-induced behavioral changes and investigated the possible therapeutic mechanism. Results showed that EA at the unilateral Zhubin (KI9–Taichong (LR3 significantly reduced METH-induced behavioral sensitization and conditioned place preference. In addition, both dopamine and tyrosine hydroxylase (TH levels decreased but monoamine oxidase A (MAO-A levels increased in the NAc of the METH-treated mice receiving EA compared with those not receiving EA. EA may be a useful nonpharmacological approach for treating METH-induced behavioral changes, probably because it reduces the METH-induced TH expression and dopamine levels and raises MAO-A expression in the NAc.

Demonstration of a Reduced Boil-Off Dewar with Broad Area Cooling

Science.gov (United States)

Gully, W. J.; Glaister, D.; Mills, G. L.

2010-04-01

Pumped helium circulation loops are an efficient and reliable way of transferring heat from a cooled device to a cryocooler. Such loops have been proposed for cooling IR detectors and their associated optics. A Broad Area Cooling (BAC) concept, in which a helium circulation loop is used to transfer heat from a dewar shield to a cryocooler has been proposed[1]. Ball has built a novel system that uses the Stirling refrigerator's compressor to drive the circulating flow by means of valves in its transfer line, eliminating the need for a separate circulation pump. The BAC system will be described and subsystem test results will be presented. An upcoming test, in which the cryocooler will be used to cool a shield in a special test dewar[2], will be discussed.

Damping of Inter-Area Low Frequency Oscillation Using an Adaptive Wide-Area Damping Controller

DEFF Research Database (Denmark)

Yao, Wei; Jiang, L.; Fang, Jiakun

2013-01-01

This paper presents an adaptive wide-area damping controller (WADC) based on generalized predictive control (GPC) and model identification for damping the inter-area low frequency oscillations in large-scale inter-connected power system. A recursive least-squares algorithm (RLSA) with a varying...... forgetting factor is applied to identify online the reduced-order linearlized model which contains dominant inter-area low frequency oscillations. Based on this linearlized model, the generalized predictive control scheme considering control output constraints is employed to obtain the optimal control signal...... conditions and different disturbances, but also has better robustness against to the time delay existing in the remote signals. The comparison studies with the conventional lead-lag WADC are also provided....

Fighting food temptations: the modulating effects of short-term cognitive reappraisal, suppression and up-regulation on mesocorticolimbic activity related to appetitive motivation.

Science.gov (United States)

Siep, Nicolette; Roefs, Anne; Roebroeck, Alard; Havermans, Remco; Bonte, Milene; Jansen, Anita

2012-03-01

The premise of cognitive therapy is that one can overcome the irresistible temptation of highly palatable foods by actively restructuring the way one thinks about food. Testing this idea, participants in the present study were instructed to passively view foods, up-regulate food palatability thoughts, apply cognitive reappraisal (e.g., thinking about health consequences), or suppress food palatability thoughts and cravings. We examined whether these strategies affect self-reported food craving and mesocorticolimbic activity as assessed by functional magnetic resonance imaging. It was hypothesized that cognitive reappraisal would most effectively inhibit the mesocorticolimbic activity and associated food craving as compared to suppression. In addition, it was hypothesized that suppression would lead to more prefrontal cortex activity, reflecting the use of more control resources, as compared to cognitive reappraisal. Self-report results indicated that up-regulation increased food craving compared to the other two conditions, but that there was no difference in craving between the suppression and cognitive reappraisal strategy. Corroborating self-report results, the neuroimaging results showed that up-regulation increased activity in important regions of the mesocorticolimbic circuitry, including the ventral tegmental area, ventral striatum, operculum, posterior insular gyrus, medial orbitofrontal cortex and ventromedial prefrontal cortex. Contrary to our hypothesis, suppression more effectively decreased activity in the core of the mesocorticolimbic circuitry (i.e., ventral tegmental area and ventral striatum) compared to cognitive reappraisal. Overall, the results support the contention that appetitive motivation can be modulated by the application of short-term cognitive control strategies. Copyright © 2012 Elsevier Inc. All rights reserved.

Blockade of central nicotine acetylcholine receptor signaling attenuate ghrelin-induced food intake in rodents.

Science.gov (United States)

Dickson, S L; Hrabovszky, E; Hansson, C; Jerlhag, E; Alvarez-Crespo, M; Skibicka, K P; Molnar, C S; Liposits, Z; Engel, J A; Egecioglu, E

2010-12-29

Here we sought to determine whether ghrelin's central effects on food intake can be interrupted by nicotine acetylcholine receptor (nAChR) blockade. Ghrelin regulates mesolimbic dopamine neurons projecting from the ventral tegmental area (VTA) to the nucleus accumbens, partly via cholinergic VTA afferents originating in the laterodorsal tegmental area (LDTg). Given that these cholinergic projections to the VTA have been implicated in natural as well as drug-induced reinforcement, we sought to investigate the role of cholinergic signaling in ghrelin-induced food intake as well as fasting-induced food intake, for which endogenous ghrelin has been implicated. We found that i.p. treatment with the non-selective centrally active nAChR antagonist, mecamylamine decreased fasting-induced food intake in both mice and rats. Moreover, central administration of mecamylamine decreased fasting-induced food intake in rats. I.c.v. ghrelin-induced food intake was suppressed by mecamylamine i.p. but not by hexamethonium i.p., a peripheral nAChR antagonist. Furthermore, mecamylamine i.p. blocked food intake following ghrelin injection into the VTA. Expression of the ghrelin receptor, the growth hormone secretagogue receptor 1A, was found to co-localize with choline acetyltransferase, a marker of cholinergic neurons, in the LDTg. Finally, mecamylamine treatment i.p. decreased the ability of palatable food to condition a place preference. These data suggest that ghrelin-induced food intake is partly mediated via nAChRs and that nicotinic blockade decreases the rewarding properties of food. Copyright © 2010 IBRO. Published by Elsevier Ltd. All rights reserved.

Accurate tissue area measurements with considerably reduced radiation dose achieved by patient-specific CT scan parameters

DEFF Research Database (Denmark)

Brandberg, J.; Bergelin, E.; Sjostrom, L.

2008-01-01

A low-dose technique was compared with a standard diagnostic technique for measuring areas of adipose and muscle tissue and CT numbers for muscles in a body composition application. The low-dose technique was intended to keep the expected deviation in the measured area of adipose and muscle tissu...

Biodiversity mapping in sensitive areas

Energy Technology Data Exchange (ETDEWEB)

Jensen, Tor; Ulssnes, Amund; Nissen-Lie, Torild [DNV, Oslo (Norway)

2008-07-01

When oil companies are entering new unexplored areas their potential footprint on the environment should be measured in a way that necessary action could be included in the planning of the activity. These actions should reduce the impact to accepted levels. Traditional baseline studies, including sediment and macro fauna sampling, are carried out in homogeneous areas. In heterogeneous and unexplored areas there is a need for more information than these traditional sediment analyses can give. To increase the knowledge from specific areas biodiversity mapping has been carried out. To combine the knowledge from ROV surveys, modelling, current measurements, sediment characteristics, seismic, macro fauna and background levels of chemicals contents in the sediments, both prior to the exploration, and after the drilling have taken place the operator can document their footprint on the marine environment. (author)

Network integration modelling of feeder and BRT(bus rapid transit) to reduce the usage of private vehicles in Palembang’s suburban area

Science.gov (United States)

Nur'afalia, D.; Afifa, F.; Rubianto, L.; Handayeni, K. D. M. E.

2018-01-01

The aim of this research is to determine the optimal feeder network route that integrates with BRT (Bus Rapid Transit). Palembang, a high growing population city with unresolved transportation demand sector. BRT as main public transportation could not fulfill people’s demand in transportation, especially in Alang-Alang Lebar sub-district. As an impact, the usage of private vehicles increases along the movement toward the city center. The concept of Network Integration that integrates feeder network with BRT is expected to be a solution to suppress the rate of private vehicles’ usage and to improve public transportation service, so that the use of BRT will be increased in the suburban area of Palembang. The method used to identifying the optimal route using Route Analysis method is route analysis using Tranetsim 0.4. The best route is obtained based on 156 movement samples. The result is 58,7% from 199 mobility’s potency of private vehicle usage’s can be reduced if there is a feeder network’s route in Alang-Alang Lebar’s sub-district. From the result, the existance of integration between feeder network and BRT is potential enough to reduce the usage of private vehicles and supports the sustainability of transportation mobility in Palembang City.

Effects of reduced-impact logging on fish assemblages in central Amazonia.

Science.gov (United States)

Dias, Murilo S; Magnusson, William E; Zuanon, Jansen

2010-02-01

In Amazonia reduced-impact logging, which is meant to reduce environmental disturbance by controlling stem-fall directions and minimizing construction of access roads, has been applied to large areas containing thousands of streams. We investigated the effects of reduced-impact logging on environmental variables and the composition of fish in forest streams in a commercial logging concession in central Amazonia, Amazonas State, Brazil. To evaluate short-term effects, we sampled 11 streams before and after logging in one harvest area. We evaluated medium-term effects by comparing streams in 11 harvest areas logged 1-8 years before the study with control streams in adjacent areas. Each sampling unit was a 50-m stream section. The tetras Pyrrhulina brevis and Hemigrammus cf. pretoensis had higher abundances in plots logged > or =3 years before compared with plots logged fish composition did not differ two months before and immediately after reduced-impact logging. Temperature and pH varied before and after logging, but those differences were compatible with normal seasonal variation. In the medium term, temperature and cover of logs were lower in logged plots. Differences in ordination scores on the basis of relative fish abundance between streams in control and logged areas changed with time since logging, mainly because some common species increased in abundance after logging. There was no evidence of species loss from the logging concession, but differences in log cover and ordination scores derived from relative abundance of fish species persisted even after 8 years. For Amazonian streams, reduced-impact logging appears to be a viable alternative to clear-cut practices, which severely affect aquatic communities. Nevertheless, detailed studies are necessary to evaluated subtle long-term effects.

Self-consistent areas law in QCD

International Nuclear Information System (INIS)

Makeenko, Yu.M.; Migdal, A.A.

1980-01-01

The problem of obtaining the self-consistent areas law in quantum chromodynamics (QCD) is considered from the point of view of the quark confinement. The exact equation for the loop average in multicolor QCD is reduced to a bootstrap form. Its iterations yield new manifestly gauge invariant perturbation theory in the loop space, reproducing asymptotic freedom. For large loops, the areas law apprears to be a self-consistent solution

REM sleep modulation by perifornical orexinergic inputs to the pedunculo-pontine tegmental neurons in rats.

Science.gov (United States)

Khanday, M A; Mallick, B N

2015-11-12

Rapid eye movement sleep (REMS) is regulated by the interaction of the REM-ON and REM-OFF neurons located in the pedunculo-pontine-tegmentum (PPT) and the locus coeruleus (LC), respectively. Many other brain areas, particularly those controlling non-REMS (NREMS) and waking, modulate REMS by modulating these REMS-related neurons. Perifornical (PeF) orexin (Ox)-ergic neurons are reported to increase waking and reduce NREMS as well as REMS; dysfunction of the PeF neurons are related to REMS loss-associated disorders. Hence, we were interested in understanding the neural mechanism of PeF-induced REMS modulation. As a first step we have recently reported that PeF Ox-ergic neurons modulate REMS by influencing the LC neurons (site for REM-OFF neurons). Thereafter, in this in vivo study we have explored the role of PeF inputs on the PPT neurons (site for REM-ON neurons) for the regulation of REMS. Chronic male rats were surgically prepared with implanted bilateral cannulae in PeF and PPT and electrodes for recording sleep-waking patterns. After post-surgical recovery sleep-waking-REMS were recorded when bilateral PeF neurons were stimulated by glutamate and simultaneously bilateral PPT neurons were infused with either saline or orexin receptor1 (OX1R) antagonist. It was observed that PeF stimulation increased waking and decreased NREMS as well as REMS, which were prevented by OX1R antagonist into the PPT. We conclude that the PeF stimulation-induced reduction in REMS was likely to be due to inhibition of REM-ON neurons in the PPT. As waking and NREMS are inversely related, subject to confirmation, the reduction in NREMS could be due to increased waking or vice versa. Based on our findings from this and earlier studies we have proposed a model showing connections between PeF- and PPT-neurons for REMS regulation. Copyright © 2015 IBRO. Published by Elsevier Ltd. All rights reserved.

Distribution of Wfs1 protein in the central nervous system of the mouse and its relation to clinical symptoms of the Wolfram syndrome

DEFF Research Database (Denmark)

Luuk, H.; Koks, S.; Plaas, M.

2008-01-01

enrichment of Wf1 protein in the central extended amygdala and ventral striatum. Prominent Wfs1 expression was seen in the hippocampal CA1 region, parasubiculum, superficial part of the second and third layers of the prefrontal cortex and proisocortical areas, hypothalamic magnocellular neurosecretory system......, alveus, fimbria, dorsal hippocampal commissure; subiculum, and to a lesser extent in the central sublenticular extended amygdala, compact part of substantia nigra, and ventral tegmental area. The neuroanatomical findings suggest that the lack of Wf1 protein function can be related to several neurological...... and psychiatric symptoms found in Wolfram syndrome. Enrichment of Wfs1 protein in the central extended amygdala suggests a role in the modulation of anxiety and fear Udgivelsesdato: 2008/8/20...

Reduced uncertainty of regional scale CLM predictions of net carbon fluxes and leaf area indices with estimated plant-specific parameters

Science.gov (United States)

Post, Hanna; Hendricks Franssen, Harrie-Jan; Han, Xujun; Baatz, Roland; Montzka, Carsten; Schmidt, Marius; Vereecken, Harry

2016-04-01

Reliable estimates of carbon fluxes and states at regional scales are required to reduce uncertainties in regional carbon balance estimates and to support decision making in environmental politics. In this work the Community Land Model version 4.5 (CLM4.5-BGC) was applied at a high spatial resolution (1 km2) for the Rur catchment in western Germany. In order to improve the model-data consistency of net ecosystem exchange (NEE) and leaf area index (LAI) for this study area, five plant functional type (PFT)-specific CLM4.5-BGC parameters were estimated with time series of half-hourly NEE data for one year in 2011/2012, using the DiffeRential Evolution Adaptive Metropolis (DREAM) algorithm, a Markov Chain Monte Carlo (MCMC) approach. The parameters were estimated separately for four different plant functional types (needleleaf evergreen temperate tree, broadleaf deciduous temperate tree, C3-grass and C3-crop) at four different sites. The four sites are located inside or close to the Rur catchment. We evaluated modeled NEE for one year in 2012/2013 with NEE measured at seven eddy covariance sites in the catchment, including the four parameter estimation sites. Modeled LAI was evaluated by means of LAI derived from remotely sensed RapidEye images of about 18 days in 2011/2012. Performance indices were based on a comparison between measurements and (i) a reference run with CLM default parameters, and (ii) a 60 instance CLM ensemble with parameters sampled from the DREAM posterior probability density functions (pdfs). The difference between the observed and simulated NEE sum reduced 23% if estimated parameters instead of default parameters were used as input. The mean absolute difference between modeled and measured LAI was reduced by 59% on average. Simulated LAI was not only improved in terms of the absolute value but in some cases also in terms of the timing (beginning of vegetation onset), which was directly related to a substantial improvement of the NEE estimates in

Optogenetic stimulation of VTA dopamine neurons reveals that tonic but not phasic patterns of dopamine transmission reduce ethanol self-administration

Directory of Open Access Journals (Sweden)

Caroline E Bass

2013-11-01

Full Text Available There is compelling evidence that acute ethanol exposure stimulates ventral tegmental area (VTA dopamine cell activity and that VTA-dependent dopamine release in terminal fields within the nucleus accumbens plays an integral role in the regulation of ethanol drinking behaviors. Unfortunately, due to technical limitations, the specific temporal dynamics linking VTA dopamine cell activation and ethanol self-administration are not known. In fact, establishing a causal link between specific patterns of dopamine transmission and ethanol drinking behaviors has proven elusive. Here, we sought to address these gaps in our knowledge using a newly developed viral-mediated gene delivery strategy to selectively express Channelrhodopsin-2 (ChR2 on dopamine cells in the VTA of wild-type rats. We then used this approach to precisely control VTA dopamine transmission during voluntary ethanol drinking sessions. The results confirmed that ChR2 was selectively expressed on VTA dopamine cells and delivery of blue light pulses to the VTA induced dopamine release in accumbal terminal fields with very high temporal and spatial precision. Brief high frequency VTA stimulation induced phasic patterns of dopamine release in the nucleus accumbens. Lower frequency stimulation, applied for longer periods mimicked tonic increases in accumbal dopamine. Notably, using this optogenetic approach in rats engaged in an intermittent ethanol drinking procedure, we found that tonic, but not phasic, stimulation of VTA dopamine cells selectively attenuated ethanol drinking behaviors. Collectively, these data demonstrate the effectiveness of a novel viral targeting strategy that can be used to restrict opsin expression to dopamine cells in standard outbred animals and provide the first causal evidence demonstrating that tonic activation of VTA dopamine neurons selectively decreases ethanol self-administration behaviors.

Report on survey of the CO2 reducing effects of regional heat supply system for urban areas in FY 1997; 1997 nendo chosa hokokusho (toshiiki wo taisho to shita koiki netsu kyokyu system no CO2 sakugen koka ni kansuru chosa)

Energy Technology Data Exchange (ETDEWEB)

NONE

1998-03-01

This report introduces regional heat supply systems using unused energy in Japan and overseas. Evaluation examples of their CO2 reducing effects are arranged. The introduction effects were quantitatively evaluated in some urban areas in Tokyo. For the evaluation, not only the conventional energy efficiency but also energy saving and CO2 reducing effects secondarily derived from the release of a rise of temperature in urban areas were quantified, to investigate their economy. Synthetic introduction effects were estimated. As a result of the case study, the system was confirmed to be a prospective option to make CO2 reduction more than 10% in the target district. Particularly in summer, about one-fourth of the effect was brought by the restriction of heat island phenomenon. When soil heat source type district heating and cooling system was applied to the whole redevelopment area, it was found that CO2 reducing effect of the whole Tokyo is only less than 0.1%. 40 refs., 64 figs., 43 tabs.

Progress in the study of reducing food allergenicity by irradiation

International Nuclear Information System (INIS)

Gu Kefei; Gao Meixu; Li Chunhong; Pan Jiarong

2006-01-01

Food allergy becomes an important factor in food safety areas. As one of the methods to cure allergy, reducing food allergenicity by irradiation becomes a hot topic. This article reviewed the present situation and the mechanism of reducing food allergenicity by irradiation. (authors)

Reducing the ecological consequences of night-time light pollution: options and developments.

Science.gov (United States)

Gaston, Kevin J; Davies, Thomas W; Bennie, Jonathan; Hopkins, John

2012-12-01

1. Much concern has been expressed about the ecological consequences of night-time light pollution. This concern is most often focused on the encroachment of artificial light into previously unlit areas of the night-time environment, but changes in the spectral composition, duration and spatial pattern of light are also recognized as having ecological effects.2. Here, we examine the potential consequences for organisms of five management options to reduce night-time light pollution. These are to (i) prevent areas from being artificially lit; (ii) limit the duration of lighting; (iii) reduce the 'trespass' of lighting into areas that are not intended to be lit (including the night sky); (iv) change the intensity of lighting; and (v) change the spectral composition of lighting.3. Maintaining and increasing natural unlit areas is likely to be the most effective option for reducing the ecological effects of lighting. However, this will often conflict with other social and economic objectives. Decreasing the duration of lighting will reduce energy costs and carbon emissions, but is unlikely to alleviate many impacts on nocturnal and crepuscular animals, as peak times of demand for lighting frequently coincide with those in the activities of these species. Reducing the trespass of lighting will maintain heterogeneity even in otherwise well-lit areas, providing dark refuges that mobile animals can exploit. Decreasing the intensity of lighting will reduce energy consumption and limit both skyglow and the area impacted by high-intensity direct light. Shifts towards 'whiter' light are likely to increase the potential range of environmental impacts as light is emitted across a broader range of wavelengths.4.Synthesis and applications. The artificial lightscape will change considerably over coming decades with the drive for more cost-effective low-carbon street lighting solutions and growth in the artificially lit area. Developing lighting strategies that minimize adverse

Chemogenetic activation of dopamine neurons in the ventral tegmental area, but not substantia nigra, induces hyperactivity in rats

NARCIS (Netherlands)

Boekhoudt, Linde; Omrani, Azar; Luijendijk, Mieneke C M; Wolterink-Donselaar, Inge G; Wijbrans, Ellen C; van der Plasse, Geoffrey; Adan, Roger A H

2016-01-01

Hyperactivity is a core symptom in various psychiatric disorders, including attention-deficit/hyperactivity disorder, schizophrenia, bipolar disorders, and anorexia nervosa. Although hyperactivity has been linked to dopaminergic  signalling, the causal relationship between midbrain dopamine neuronal

Constitutive cannabinoid 1 and mu opioid receptor activity in the ventral tegmental area: occurrence, function and therapeutic relevance

NARCIS (Netherlands)

Meye, F.J.

2012-01-01

Cannabinoid 1 receptors (CB1Rs) play a crucial role in regulating systems dedicated to processing rewards and emotions. It was known that in artificial systems, CB1Rs can exhibit activity that is independent of the typical agonist-driven form. However, it remained largely unclear whether this

Optimizing land use pattern to reduce soil erosion

Directory of Open Access Journals (Sweden)

Reza Sokouti

2017-01-01

Full Text Available Soil erosion hazard is one of the main problems can affect ecological balance in watersheds. This study aimed to determine the optimal use of land to reduce erosion and increase the resident's income of Qushchi watershed in West Azerbaijan province, Iran. Income and expenses for the current land uses were calculated with field studies. Damages resulting from the soil erosion were estimated by soil depth equal to the specified land uses. For three different options including the current status of land uses without and with land management, and the standard status of land uses, multi-objective linear programming model was established by LINGO software. Then the optimization problem of the land use was solved by simplex method. Finally, the best option of land use was determined by comparing erosion rate and its cost in each scenario. Then the circumstances and the recommended conditions were compared. The results indicated that the current surface area of current land uses is not suitable to reduce erosion and increase income of residents and should change in the optimum conditions. At the optimum level, there should change horticulture area of 408 to 507 (ha, irrigated land area of 169 to 136 (ha and dry farming of 636 to 570 (ha, while conversion of rangeland area not indispensable. In addition, the results showed that in case of the optimization of land use, soil erosion and the profitability of the whole area will decrease 0.75% and increase 3.68%, respectively. In case of land management practices, soil erosion will decrease 42.27% and the profitability increase 21.39% while in the standard conditions, soil erosion will decrease 60.95% and profitability will increase 24.20%. The results of the sensitivity analysis showed that the changes in the horticulture and range land areas have the greatest impact on the increasing profitability and reducing soil erosion of Qushchi watershed. So, it is recommended using Education and Extension to promote

PELVIC AREA ASSESSMENT IN BUNAJI AND RAHAJI COWS ...

African Journals Online (AJOL)

Keywords: Fostering calving ease, pelvic area assessment, Bunaji, Rahaji. Abstract. Pelvic area (P.A.) assessment may be used as management tool to reduce the risks associated with dystocia and foster calving ease. Relationship between cow's P.A. and age can aid pre- breeding culling decisions. This study used 100 ...

Zones 30 : urban residential areas.

NARCIS (Netherlands)

2006-01-01

Sustainable Safety uses a road categorization in which through traffic is concentrated on motorways and other main roads. In residential areas, which have a living, shopping, or work function, through traffic is discouraged by setting a speed limit of 30 km/h, and by speed reducing measures such as

Shellfish Fishery Severely Reduces Condition and Survival of Oystercatchers Despite Creation of Large Marine Protected Areas

Directory of Open Access Journals (Sweden)

Simon Verhulst

2004-06-01

Full Text Available Fisheries and other human activities pose a global threat to the marine environment. Marine protected areas (MPAs are an emerging tool to cope with such threats. In the Dutch Wadden Sea, large MPAs (covering 31% of all intertidal flats have been created to protect shellfish-eating birds and allow recovery of important habitats. Even though shellfish fishing is prohibited in these areas, populations of shellfish-eating birds in the Wadden Sea have declined sharply. The role of shellfish fisheries in these declines is hotly debated, therefore, we investigated the effectiveness of MPAs for protecting oystercatcher (Haematopus ostralegus populations. Shellfish stocks (cockles, Cerastoderma edule were substantially higher in the MPAs, but surprisingly this has not resulted in a redistribution of wintering oystercatchers. Oystercatchers in unprotected areas had less shellfish in their diet and lower condition (a combined measure of mass and haematological parameters, and their estimated mortality was 43% higher. It is likely, therefore, that shellfish fishing explains at least part of the 40% decline in oystercatcher numbers in recent years. Condition and mortality effects were strongest in males, and the population sex ratio was female biased, in agreement with the fact that males rely more on shellfish. The unprotected areas apparently function as an "ecological trap," because oystercatchers did not respond as anticipated to the artificial spatial heterogeneity in food supply. Consequently, the MPAs are effective on a local scale, but not on a global scale. Similar problems are likely to exist in terrestrial ecosystems, and distribution strategies of target species need to be considered when designing terrestrial and marine protected areas if they are to be effective.

Wide area Hyperspectral Motion Imaging

Science.gov (United States)

2017-02-03

detection at a manageable false alarm rate using the adaptive coherence estimator algorithm. A radiance spectrum was calculated with MODTRAN at 5km...1mHz. In order to meet SNR and update rate, the area coverage is reduced to less than the size of a football stadium. An interferometer has

Synthesis of Adaptation Options for Coastal Areas

Science.gov (United States)

Adaptation can help reduce the long-term costs associated with climate change. This document provides an introduction to climate change impacts and adaptation options for estuaries, beaches and coastal areas.

Towards a better Understanding and reducing of the Groundwater Contamination in Saint Katherine area, Sinai, Egypt; Using Remote Sensing and Chemical Analyses

Science.gov (United States)

Fekri, A.; Mohamed, L.

2017-12-01

Egypt has a big water shortage problem because of the high population density and the lack of the surface water resources. So it was necessary to identify additional clean water resources and among all of the other alternative water resources, groundwater should be the most appropriate choice for Egyptians to explore and develop. Saint Katherine area is located in the highest mountainous area of southern Sinai including parallel ridges separated by deep wadis which have been cut along faults and fractures and enlarged through intense precipitation events during the old pluvial periods. Katherina volcanics and the surrounding granitic rocks in Saint Katherine area, which are generally impermeable except through fractures such as faults, joints and shear zones, are recharged with 50 mm annual precipitation. The groundwater recharge find a way through sets of interconnected joints to feed the existing wells in the low-lying fault zones. After the St. Katherine Protectorate was activated in 1996, public awareness of the possible harmful impact of the existing inadequate sewage disposal increased. The groundwater contamination (nitrates and coliform bacteria) in St. Katherine area causes health problems such as diarrhea and skin infections due to the use of well water for household purposes. This study will focus on; monitoring, evaluating and cleaning up the contaminant distribution in St. Katherine groundwater, using a conceptual model for the fault control on the groundwater flow in fractured basement aquifers to understand the possible pathways for the contaminated groundwater (using remote sensing data), and by preparing disinfectant tracers. It is known that Coliform bacteria could be treated by using Sulfanilamide drug, but in this study we will modify the Sulfanilamide compounds which are considered as ligands containing N, O, S donor atoms that could be used to uptake the transition metals, and produce a colored complex. The produced complex will work as a

Remedial action in areas of enhanced natural background radiation levels (with particular emphasis in areas with mineral sand mining residues)

International Nuclear Information System (INIS)

Swindon, T.N.

1985-01-01

In areas where individuals may receive doses from natural background sources which are higher than those received in areas of normal background radiation, it may be considered desirable that some remedial action be taken to reduce those doses. Contributions to these higher doses may be through high gamma ray fields from the ground or from the use of local building materials, the intake of food or water derived from the areas or of food covered with dust from the areas, the ingestion of dirt and the inhalation of dust, and radon or thoron. Guidelines for remedial action in areas where residues from mineral sand mining and processing have been deposited are given

Startle reduces recall of a recently learned internal model.

Science.gov (United States)

Wright, Zachary; Patton, James L; Ravichandran, Venn

2011-01-01

Recent work has shown that preplanned motor programs are released early from subcortical areas by the using a startling acoustic stimulus (SAS). Our question is whether this response might also contain a recently learned internal model, which draws on experience to predict and compensate for expected perturbations in a feedforward manner. Studies of adaptation to robotic forces have shown some evidence of this, but were potentially confounded by cocontraction caused by startle. We performed a new adaptation experiment using a visually distorted field that could not be confounded by cocontraction. We found that in all subjects that exhibited startle, the startle stimulus (1) reduced performance of the recently learned task (2) reduced after-effect magnitudes. Because startle reduced but did not eliminate the recall of learned control, we suggest that multiple neural centers (cortical and subcortical) are involved in such learning and adaptation, which can impact training areas such as piloting, teleoperation, sports, and rehabilitation. © 2011 IEEE

IMPORTANCE OF MANGROVE TO REDUCE THE TSUNAMI WAVE ENERGY

Directory of Open Access Journals (Sweden)

Anastasia Neni Candra Purnamasari

2017-09-01

Full Text Available Mangrove has a very important role to reduce the tsunami wave energy. It is shown that the coastal areas have no vegetation or in this case will have an impact Mangrove forests greater damage due to tsunami waves than the coastal areas of vegetation. The purpose of the Term Paper is proved the importance of Mangrove to reduce the tsunami wave energy by comparing the various methods that have been observed in some case studies on the impact of the tsunami that occurred in several Asian countries in 2004 and case studies on ocean waves on the Gulf coast of south Florida. Based on the research results that could dampen Mangrove Tsunami wave energy. Tsunami wave energy can be reduced by several factors, namely mangrove species, tree size, vast mangrove forest, nature tree structure, and the size limit Mangrove forest (as far as how much of the ocean to the surface.

Additive-manufactured patient-specific titanium templates for thoracic pedicle screw placement: novel design with reduced contact area.

Science.gov (United States)

Takemoto, Mitsuru; Fujibayashi, Shunsuke; Ota, Eigo; Otsuki, Bungo; Kimura, Hiroaki; Sakamoto, Takeshi; Kawai, Toshiyuki; Futami, Tohru; Sasaki, Kiyoyuki; Matsushita, Tomiharu; Nakamura, Takashi; Neo, Masashi; Matsuda, Shuich

2016-06-01

Image-based navigational patient-specific templates (PSTs) for pedicle screw (PS) placement have been described. With recent advances in three-dimensional computer-aided designs and additive manufacturing technology, various PST designs have been reported, although the template designs were not optimized. We have developed a novel PST design that reduces the contact area without sacrificing stability. It avoids susceptibility to intervening soft tissue, template geometric inaccuracy, and difficulty during template fitting. Fourteen candidate locations on the posterior aspect of the vertebra were evaluated. Among them, locations that had high reproducibility on computed tomography (CT) images and facilitated accurate PS placement were selected for the final PST design. An additive manufacturing machine (EOSINT M270) fabricated the PSTs using commercially pure titanium powder. For the clinical study, 36 scoliosis patients and 4 patients with ossification of the posterior longitudinal ligament (OPLL) were treated with thoracic PSs using our newly developed PSTs. We intraoperatively and postoperatively evaluated the accuracy of the PS hole created by the PST. Based on the segmentation reproducibility and stability analyses, we selected seven small, round contact points for our PST: bilateral superior and inferior points on the transverse process base, bilateral inferior points on the laminar, and a superior point on the spinous process. Clinically, the success rates of PS placement using this PST design were 98.6 % (414/420) for scoliosis patients and 100 % (46/46) for OPLL patients. This study provides a useful design concept for the development and introduction of patient-specific navigational templates for placing PSs.

Rainfall Runoff Mitigation by Retrofitted Permeable Pavement in an Urban Area

Directory of Open Access Journals (Sweden)

Muhammad Shafique

2018-04-01

Full Text Available Permeable pavement is an effective low impact development (LID practice that can play an important role in reducing rainfall runoff amount in urban areas. Permeable interlocking concrete pavement (PICP was retrofitted in a tremendously developed area of Seoul, Korea and the data was monitored to evaluate its effect on the hydrology and stormwater quality performance for four months. Rainfall runoff was first absorbed by different layers of the PICP system and then contributed to the sewage system. This not only helps to reduce the runoff volume, but also increase the time of concentration. In this experiment, different real rain events were observed and the field results were investigated to check the effectiveness of the PICP system for controlling the rainfall runoff in Songpa, Korea. From the analysis of data, results showed that the PCIP system was very effective in controlling rainfall runoff. Overall runoff reduction performance from the PCIP was found to be around 30–65% during various storm events. In addition, PICP significantly reduced peak flows in different storm events which is very helpful in reducing the chances of water-logging in an urbanized area. Research results also allow us to sum up that retrofitted PICP is a very effective approach for rainfall runoff management in urban areas.

ProSAAS-derived peptides are regulated by cocaine and are required for sensitization to the locomotor effects of cocaine.

Science.gov (United States)

Berezniuk, Iryna; Rodriguiz, Ramona M; Zee, Michael L; Marcus, David J; Pintar, John; Morgan, Daniel J; Wetsel, William C; Fricker, Lloyd D

2017-11-01

To identify neuropeptides that are regulated by cocaine, we used a quantitative peptidomic technique to examine the relative levels of neuropeptides in several regions of mouse brain following daily intraperitoneal administration of 10 mg/kg cocaine or saline for 7 days. A total of 102 distinct peptides were identified in one or more of the following brain regions: nucleus accumbens, caudate putamen, frontal cortex, and ventral tegmental area. None of the peptides detected in the caudate putamen or frontal cortex were altered by cocaine administration. Three peptides in the nucleus accumbens and seven peptides in the ventral tegmental area were significantly decreased in cocaine-treated mice. Five of these ten peptides are derived from proSAAS, a secretory pathway protein and neuropeptide precursor. To investigate whether proSAAS peptides contribute to the physiological effects of psychostimulants, we examined acute responses to cocaine and amphetamine in the open field with wild-type (WT) and proSAAS knockout (KO) mice. Locomotion was stimulated more robustly in the WT compared to mutant mice for both psychostimulants. Behavioral sensitization to amphetamine was not maintained in proSAAS KO mice and these mutants failed to sensitize to cocaine. To determine whether the rewarding effects of cocaine were altered, mice were tested in conditioned place preference (CPP). Both WT and proSAAS KO mice showed dose-dependent CPP to cocaine that was not distinguished by genotype. Taken together, these results suggest that proSAAS-derived peptides contribute differentially to the behavioral sensitization to psychostimulants, while the rewarding effects of cocaine appear intact in mice lacking proSAAS. © 2017 International Society for Neurochemistry.

The "proactive" model of learning: Integrative framework for model-free and model-based reinforcement learning utilizing the associative learning-based proactive brain concept.

Science.gov (United States)

Zsuga, Judit; Biro, Klara; Papp, Csaba; Tajti, Gabor; Gesztelyi, Rudolf

2016-02-01

Reinforcement learning (RL) is a powerful concept underlying forms of associative learning governed by the use of a scalar reward signal, with learning taking place if expectations are violated. RL may be assessed using model-based and model-free approaches. Model-based reinforcement learning involves the amygdala, the hippocampus, and the orbitofrontal cortex (OFC). The model-free system involves the pedunculopontine-tegmental nucleus (PPTgN), the ventral tegmental area (VTA) and the ventral striatum (VS). Based on the functional connectivity of VS, model-free and model based RL systems center on the VS that by integrating model-free signals (received as reward prediction error) and model-based reward related input computes value. Using the concept of reinforcement learning agent we propose that the VS serves as the value function component of the RL agent. Regarding the model utilized for model-based computations we turned to the proactive brain concept, which offers an ubiquitous function for the default network based on its great functional overlap with contextual associative areas. Hence, by means of the default network the brain continuously organizes its environment into context frames enabling the formulation of analogy-based association that are turned into predictions of what to expect. The OFC integrates reward-related information into context frames upon computing reward expectation by compiling stimulus-reward and context-reward information offered by the amygdala and hippocampus, respectively. Furthermore we suggest that the integration of model-based expectations regarding reward into the value signal is further supported by the efferent of the OFC that reach structures canonical for model-free learning (e.g., the PPTgN, VTA, and VS). (c) 2016 APA, all rights reserved).

Synthesis of battery grade reduced silver powder

International Nuclear Information System (INIS)

Qadeer, R.; Hameed, M.; Ikram, S.; Munir, A.

2002-01-01

Process for production of battery grade reduced silver powder, an active positive material for zinc-silver oxide batteries, having specific characteristics has been optimized and the synthesized reduced silver powder was characterized. Results reveal that the values of bulk density (1.25 0.1 g/cm3) and activity (73.27 %) of synthesized reduced silver powder lies within the recommended range for use as battery material. It has purity ≥ 98% and contains Fe and Cu as traces in the concentration range of 30 5 ppm and 15 7 ppm respectively. Others determined values of surface and pores parameters are: surface area 2.6 .4 m2/g: pore volume 3.10 cm3/g: pore diameter 0.043 mu m and porosity 20%. XRD studies reveal that reduced silver powder has a cubic structure. (author)

Designing integrated energy and spatial development for sustainable urban areas in the Northern Netherlands

NARCIS (Netherlands)

Zheng, Ling

2006-01-01

This study aims to reduce CO2 emission in an efficient way in urban areas by reducing conventional energy use and implementing renewable energy. The research urban area is Zuidlanden, located in the south of Leeuwarden in the north of the Netherlands. The

Semiworks source aggregate area management study report

International Nuclear Information System (INIS)

1993-05-01

This report presents the results of an aggregate area management study (AAMS) for the Semi-Works Aggregate Area in the 200 Areas of the US Department of Energy (DOE) . Hanford Site in Washington State. This scoping level study provides the basis for initiating Remedial Investigation/Feasibility Study (RI/FS) activities under the Comprehensive Environmental Response, Compensation, and Liability Act of 1980 (CERCLA) or Resource Conservation and Recovery Act (RCRA) Facility Investigations WD and Corrective Measures Studies (CMS) under RCRA. This report also integrates select RCRA treatment storage, or disposal (TSD) closure activities with CERCLA and RCRA past-practice investigations. This approach is described and justified in The Hanford Federal Facility Agreement and Consent Order Change Package. This strategy provides new concepts for: accelerating decision-malting by maximizing the use of existing data consistent with data quality objectives (DQOs); and undertaking expedited response actions (ERAS) and/or interim remedial measures (IRMs), as appropriate, to either remove threats to human health and welfare and the environment, or to reduce risk by reducing toxicity, mobility, or volume of contaminants

Septo-Hippocampo-Septal Loop and Memory Formation

Directory of Open Access Journals (Sweden)

Fatemeh Khakpai

2013-01-01

Full Text Available   Cholinergic and GABAergic fibers in the medial septal/diagonal band of Broca (MS/DB area project to the hippocampus and constitute the septo-hippocampal pathway, which has been proven in learning and memory. In addition, the hippocampus has bidirectional connections with the septum, which use this relation for self-regulation of cholinergic input.   The activity of septal and hippocampal neurons is modulated by several neurotransmitters including glutamatergic neurons from the entorhinal cortex, serotonergic fibers from the raphe nucleus, dopaminergic neurons from the ventral tegmental area (VTA, histaminergic cells from the tuberomammillary nucleus and adrenergic fibers from the locus coeruleus (LC. Thus, changes in the glutamatergic, serotonergic and etc. mediated transmission in the MS/DB may influence cholinergic or GABAergic transmission in the hippocampus.

Septo-Hippocampo-Septal Loop and Memory Formation

Directory of Open Access Journals (Sweden)

Fatemeh Khakpai

2013-02-01

Full Text Available The Cholinergic and GABAergic .bers of the medial septal/diagonal band of Broca (MS/DB area project to the hippocampus and constitute the septo-hippocampal pathway, which has been proven to play a role in learning and memory. In addition, the hippocampus has bidirectional connections with the septum so that to self-regulate of cholinergic input. The activity of septal and hippocampal neurons is modulated by several neurotransmitter systems including glutamatergic neurons from the entorhinal cortex, serotonergic .bers from the raphe nucleus, dopaminergic neurons from the ventral tegmental area (VTA, histaminergic cells from the tuberomammillary nucleus and adrenergic .bers from the locus coeruleus (LC. Thus, changes in the glutamatergic, serotonergic and other systems- mediated transmission in the MS/DB may in.uence cholinergic or GABAergic transmission in the hippocampus.

Preparation of potassium-reduced tantalum powders

International Nuclear Information System (INIS)

Kolosov, V.N.; Miroshnichenko, M.N.; Orlov, V.M.; Prokhorova, T.Yu.

2005-01-01

Characteristics of tantalum powders prepared by reduction of molten potassium heptafluorotantalate with liquid potassium are studied in a temperature range of 750 - 850 deg C using potassium chloride as a flux at a ratio of K 2 TaF 7 : KCl = 1, 2, and 3. The use of potassium as a reducing agent facilitates washing of tantalum powders for impurity salt removal, reduces sodium content and leakage currents in the anodes. As compared to sodium process, the potassium reduction results in a high yield of sponge material, a decrease in the specific surface area and yield of tantalum powder suitable for manufacture of capacitor anodes [ru

Terminal Area Conflict Detection and Resolution Tool

Science.gov (United States)

Verma, Savita Arora

2011-01-01

This poster will describe analysis of a conflict detection and resolution tool for the terminal area called T-TSAFE. With altitude clearance information, the tool can reduce false alerts to as low as 2 per hour.

Does the cerebral cortex exacerbate dopaminergic cell death in the substantia nigra of 6OHDA-lesioned rats?

Science.gov (United States)

Luquin, Natasha; Mitrofanis, John

2008-01-01

We have explored the survival of dopaminergic cells of the substantia nigra pars compacta (SNc) in 6 hydroxydopamine (6OHDA)-lesioned rats with prior cortical removal. There were approximately 35% more dopaminergic cells in the ventral sector of SNc (vSNc) of 6OHDA-lesioned rats that had prior cortical removal compared to those that did not. By contrast, there were no differences in dopaminergic cell number between these experimental groups in the ventral tegmental area (VTA) and the dorsal sector of SNc (dSNc). Hence, prior cortical removal in 6OHDA-lesioned rats neuroprotected vSNc--but not VTA or dSNc--dopaminergic cells from death.

Driving the need to feed: Insight into the collaborative interaction between ghrelin and endocannabinoid systems in modulating brain reward systems.

Science.gov (United States)

Edwards, Alexander; Abizaid, Alfonso

2016-07-01

Independent stimulation of either the ghrelin or endocannabinoid system promotes food intake and increases adiposity. Given the similar distribution of their receptors in feeding associated brain regions and organs involved in metabolism, it is not surprising that evidence of their interaction and its importance in modulating energy balance has emerged. This review documents the relationship between ghrelin and endocannabinoid systems within the periphery and hypothalamus (HYP) before presenting evidence suggesting that these two systems likewise work collaboratively within the ventral tegmental area (VTA) to modulate non-homeostatic feeding. Mechanisms, consistent with current evidence and local infrastructure within the VTA, will be proposed. Copyright © 2016 Elsevier Ltd. All rights reserved.

Thinner eggshells of dipper (Cinclus cinclus) eggs from an acidified area compared to a non-acidified area in Norway

Energy Technology Data Exchange (ETDEWEB)

Nyboe, S.; Staurnes, M.; Jerstad, K. [Norwegian University of Science and Technology, Dragvoll (Norway). Dept. of Zoology

1997-01-01

Eggs of dippers Cinclus cinclus from a chronically acidified area in Southern Norway were compared with eggs from a non-acidified area in Central Norway. There were no differences in egg size, as measured by volume, weight, length and calculated surface area, between the two areas. Eggshells were 7.0% lighter and 6.1% thinner, as measured by the Ratcliffe index and 7.0% as measured by the eggshell index (shell weight/surface area) in Southern Norway than in Central Norway. The Ratcliffe and eggshell indices were highly correlated. Scanning electron micrography showed that the palisade layer of eggshells of eggs from the acidified area was 10.7% thinner than that of eggshells of eggs from the non-acidified area. Eggshell vapour permeability was not significantly influenced by area. Since the moderately lower thickness in Southern Norway was not accompanied by higher vapour permeability, this indicates that the reduced eggshell thickness did not cause desiccation of dipper eggs in the acidified area. The possibility of underestimating the environmental effects of acidification on dippers is discussed. 42 refs.,2 figs., 4 tabs.

Reduction of radiation area project plan

International Nuclear Information System (INIS)

1979-08-01

This plan deals with the overall reduction of outdoor surface radiation areas under Rockwell's jurisdiction. Four basic alternatives are identified which will reduce and/or stabilize radiation areas until long-term disposal decisions are made: (1) continued routine surveillance and maintenance; (2) reduction or elimination of effluent discharges; (3) improved site stabilization; and (4) site removal. The four major transport mechanisms at Hanford that are the primary forces for contamination spread are identified as wind, animal transport, concentration and dispersal by plants, and transport resulting from human activities

[Reducing inequality by improving preventing measures].

Science.gov (United States)

Valsecchi, M

2014-01-01

Terms of inequalities issue in health service are defined and the consolidated scientific acquisitions are recalled. Three prioritary areas of action are defined and described, that Prevention Departments are suggested to activate through focused programs in order to reduce specific inequalities. First area of action: includes three types of vital interventions: vaccinations, contrasting of tuberculosis infection and oncological screening that have to be granted to specific disadvantaged groups of population as Rom communities, immigrant women, prisoners e psychiatric patients. Second area of action: actions on focused urban planning aiming to improve conditions of social housing (with a special focus on thermal insulation, minimal distances to be kept towards streets of havy traffic), increase of increase of urban green spaces enjoyed by the population and contrasting degradation of housing (with particular attention to poisoning by carbon monoxide). Third area of action: actions contrasting cardiovascular diseases, that is the leading cause of death and inequalities in health for the working class population. A coordinated intervention directly in the workplace is proposed, where a particularly high percentage of individuals exposed to specific risk factors is present.

Study on the Effectiveness of Infiltration Wells to Reduce Excess Surface Run Off In ITB

Directory of Open Access Journals (Sweden)

Mardiah Afifah Muhsinatu

2018-01-01

Full Text Available Institut Teknologi Bandung (ITB, Ganesha Campus, Indonesia, has an area of 28.86 hectares. The campus is located in Bandung. Starting from 2012, new buildings were constructed within the area, reducing the area of permeable surface significantly. In the past few years, there were several excess run off incidents in the campus. The insufficient area of permeable surface as well as the inadequate capacity of the drainage system contributes to the excess surface run off. The drainage system has only two outlets. Moreover, in some areas, the drainage systems are disconnected. Thus, most the surface run off are stored within the drainage system. The purpose of this study is to evaluate the effectiveness of infiltration wells for reducing the local excess run off in ITB. Precipitation data and drained service area are used to estimate the design discharge from each building in ITB. In order to avoid the excess surface run off of certain locations in ITB, then the infiltration wells are proposed to balance the area of impermeable surface. The effectiveness of the infiltration wells are evaluated by assessing their number to their contribution in reducing the excess surface runs off.

Great tits (Parus major reduce caterpillar damage in commercial apple orchards.

Directory of Open Access Journals (Sweden)

Christel M M Mols

Full Text Available Alternative ways to control caterpillar pests and reduce the use of pesticides in apple orchards are in the interest of the environment, farmers and the public. Great tits have already been shown to reduce damage under high caterpillar density when breeding in nest boxes in an experimental apple orchard. We tested whether this reduction also occurs under practical conditions of Integrated Pest Management (IPM, as well as Organic Farming (OF, by setting up an area with nest boxes while leaving a comparable area as a control within 12 commercial orchards. We showed that in IPM orchards, but not in OF orchards, in the areas with breeding great tits, apples had 50% of the caterpillar damage of the control areas. Offering nest boxes to attract insectivorous passerines in orchards can thus lead to more limited pesticide use, thereby adding to the natural biological diversity in an agricultural landscape, while also being economically profitable to the fruit growers.

Great tits (Parus major) reduce caterpillar damage in commercial apple orchards.

Science.gov (United States)

Mols, Christel M M; Visser, Marcel E

2007-02-07

Alternative ways to control caterpillar pests and reduce the use of pesticides in apple orchards are in the interest of the environment, farmers and the public. Great tits have already been shown to reduce damage under high caterpillar density when breeding in nest boxes in an experimental apple orchard. We tested whether this reduction also occurs under practical conditions of Integrated Pest Management (IPM), as well as Organic Farming (OF), by setting up an area with nest boxes while leaving a comparable area as a control within 12 commercial orchards. We showed that in IPM orchards, but not in OF orchards, in the areas with breeding great tits, apples had 50% of the caterpillar damage of the control areas. Offering nest boxes to attract insectivorous passerines in orchards can thus lead to more limited pesticide use, thereby adding to the natural biological diversity in an agricultural landscape, while also being economically profitable to the fruit growers.

Synaptic potentiation onto habenula neurons in the learned helplessness model of depression.

Science.gov (United States)

Li, Bo; Piriz, Joaquin; Mirrione, Martine; Chung, ChiHye; Proulx, Christophe D; Schulz, Daniela; Henn, Fritz; Malinow, Roberto

2011-02-24

The cellular basis of depressive disorders is poorly understood. Recent studies in monkeys indicate that neurons in the lateral habenula (LHb), a nucleus that mediates communication between forebrain and midbrain structures, can increase their activity when an animal fails to receive an expected positive reward or receives a stimulus that predicts aversive conditions (that is, disappointment or anticipation of a negative outcome). LHb neurons project to, and modulate, dopamine-rich regions, such as the ventral tegmental area (VTA), that control reward-seeking behaviour and participate in depressive disorders. Here we show that in two learned helplessness models of depression, excitatory synapses onto LHb neurons projecting to the VTA are potentiated. Synaptic potentiation correlates with an animal's helplessness behaviour and is due to an enhanced presynaptic release probability. Depleting transmitter release by repeated electrical stimulation of LHb afferents, using a protocol that can be effective for patients who are depressed, markedly suppresses synaptic drive onto VTA-projecting LHb neurons in brain slices and can significantly reduce learned helplessness behaviour in rats. Our results indicate that increased presynaptic action onto LHb neurons contributes to the rodent learned helplessness model of depression.

Synaptic potentiation onto habenula neurons in the learned helplessness model of depression

International Nuclear Information System (INIS)

Li, B.; Schulz, D.; Piriz, J.; Mirrione, M.; Chung, C.H.; Proulx, C.D.; Schulz, D.; Henn, F.; Malinow, R.

2011-01-01

The cellular basis of depressive disorders is poorly understood. Recent studies in monkeys indicate that neurons in the lateral habenula (LHb), a nucleus that mediates communication between forebrain and midbrain structures, can increase their activity when an animal fails to receive an expected positive reward or receives a stimulus that predicts aversive conditions (that is, disappointment or anticipation of a negative outcome). LHb neurons project to, and modulate, dopamine-rich regions, such as the ventral tegmental area (VTA), that control reward-seeking behaviour and participate in depressive disorders. Here we show that in two learned helplessness models of depression, excitatory synapses onto LHb neurons projecting to the VTA are potentiated. Synaptic potentiation correlates with an animal's helplessness behaviour and is due to an enhanced presynaptic release probability. Depleting transmitter release by repeated electrical stimulation of LHb afferents, using a protocol that can be effective for patients who are depressed, markedly suppresses synaptic drive onto VTA-projecting LHb neurons in brain slices and can significantly reduce learned helplessness behaviour in rats. Our results indicate that increased presynaptic action onto LHb neurons contributes to the rodent learned helplessness model of depression.

Female employment reduces fertility in rural Senegal.

Science.gov (United States)

Van den Broeck, Goedele; Maertens, Miet

2015-01-01

Economic growth and modernization of society are generally associated with fertility rate decreases but which forces trigger this is unclear. In this paper we assess how fertility changes with increased labor market participation of women in rural Senegal. Evidence from high-income countries suggests that higher female employment rates lead to reduced fertility rates but evidence from developing countries at an early stage of demographic transition is largely absent. We concentrate on a rural area in northern Senegal where a recent boom in horticultural exports has been associated with a sudden increase in female off-farm employment. Using survey data we show that employed women have a significantly higher age at marriage and at first childbirth, and significantly fewer children. As causal identification strategy we use instrumental variable and difference-in-differences estimations, combined with propensity score matching. We find that female employment reduces the number of children per woman by 25%, and that this fertility-reducing effect is as large for poor as for non-poor women and larger for illiterate than for literate women. Results imply that female employment is a strong instrument for empowering rural women, reducing fertility rates and accelerating the demographic transition in poor countries. The effectiveness of family planning programs can increase if targeted to areas where female employment is increasing or to female employees directly because of a higher likelihood to reach women with low-fertility preferences. Our results show that changes in fertility preferences not necessarily result from a cultural evolution but can also be driven by sudden and individual changes in economic opportunities.

Reducing the impact of blue mussel (Mytilus edulis) dredging on the ecosystem in shallow water soft bottom areas

DEFF Research Database (Denmark)

Frandsen, Rikke; Eigaard, Ole Ritzau; Poulsen, Louise K.

2015-01-01

Dredging blue mussels (Mytilus edulis) and thus removing structural elements, inducing resuspension of sediment as well as reducing filtration capacity, will inevitably affect the ecosystem. The study demonstrates that the impacts of fishing can be reduced through gear developments. A new light d...

Reduced Voltage Scaling in Clock Distribution Networks

Directory of Open Access Journals (Sweden)

Khader Mohammad

2009-01-01

Full Text Available We propose a novel circuit technique to generate a reduced voltage swing (RVS signals for active power reduction on main buses and clocks. This is achieved without performance degradation, without extra power supply requirement, and with minimum area overhead. The technique stops the discharge path on the net that is swinging low at a certain voltage value. It reduces active power on the target net by as much as 33% compared to traditional full swing signaling. The logic 0 voltage value is programmable through control bits. If desired, the reduced-swing mode can also be disabled. The approach assumes that the logic 0 voltage value is always less than the threshold voltage of the nMOS receivers, which eliminate the need of the low to high voltage translation. The reduced noise margin and the increased leakage on the receiver transistors using this approach have been addressed through the selective usage of multithreshold voltage (MTV devices and the programmability of the low voltage value.

Low doses of dextromethorphan attenuate morphine-induced rewarding via the sigma-1 receptor at ventral tegmental area in rats.

Science.gov (United States)

Chen, Shiou-Lan; Hsu, Kuei-Ying; Huang, Eagle Yi-Kung; Lu, Ru-Band; Tao, Pao-Luh

2011-09-01

Chronic use of morphine causes rewarding and behavioral sensitization, which may lead to the development of psychological craving. In our previous study, we found that a widely used antitussive dextromethorphan (known as a low affinity NMDA receptor antagonist), at doses of 10-20 mg/kg (i.p.), effectively decreased morphine rewarding in rats. In this study, we further investigated the effects and mechanisms of low doses of DM (μg/kg range) on morphine rewarding and behavioral sensitization. A conditioned place preference test was used to determine the rewarding and a locomotor activity test was used to determine the behavioral sensitization induced by the drug(s) in rats. When a low dose of DM (3 or 10 μg/kg, i.p.) was co-administered with morphine (5 mg/kg, s.c.), the rewarding effect, but not behavioral sensitization, induced by morphine was inhibited. The inhibiting effect of DM could be blocked by systemically administering a sigma-1 receptor antagonist, BD1047 (3 mg/kg, i.p.). When BD1047 (5 nmole/site) was locally given at the VTA, it also blocked the effects of a low dose of DM in inhibiting morphine rewarding. Our findings suggest that the activation of the sigma-1 receptor at the VTA may be involved in the mechanism of low doses of DM in inhibiting the morphine rewarding effect and the possibility of using extremely low doses of DM in treatment of opioid addiction in clinics. Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.

Runoff estimation in residencial area

Directory of Open Access Journals (Sweden)

Meire Regina de Almeida Siqueira

2013-12-01

Full Text Available This study aimed to estimate the watershed runoff caused by extreme events that often result in the flooding of urban areas. The runoff of a residential area in the city of Guaratinguetá, São Paulo, Brazil was estimated using the Curve-Number method proposed by USDA-NRCS. The study also investigated current land use and land cover conditions, impermeable areas with pasture and indications of the reforestation of those areas. Maps and satellite images of Residential Riverside I Neighborhood were used to characterize the area. In addition to characterizing land use and land cover, the definition of the soil type infiltration capacity, the maximum local rainfall, and the type and quality of the drainage system were also investigated. The study showed that this neighborhood, developed in 1974, has an area of 792,700 m², a population of 1361 inhabitants, and a sloping area covered with degraded pasture (Guaratinguetá-Piagui Peak located in front of the residential area. The residential area is located in a flat area near the Paraiba do Sul River, and has a poor drainage system with concrete pipes, mostly 0.60 m in diameter, with several openings that capture water and sediments from the adjacent sloping area. The Low Impact Development (LID system appears to be a viable solution for this neighborhood drainage system. It can be concluded that the drainage system of the Guaratinguetá Riverside I Neighborhood has all of the conditions and characteristics that make it suitable for the implementation of a low impact urban drainage system. Reforestation of Guaratinguetá-Piagui Peak can reduce the basin’s runoff by 50% and minimize flooding problems in the Beira Rio neighborhood.

Mapping human interaction with the Bering Sea ecosystem: Comparing seasonal use areas, lifetime use areas, and "calorie-sheds"

Science.gov (United States)

Huntington, Henry P.; Ortiz, Ivonne; Noongwook, George; Fidel, Maryann; Childers, Dorothy; Morse, Muriel; Beaty, Julia; Alessa, Lilian; Kliskey, Andrew

2013-10-01

Alaska Native coastal communities interact with the marine environment in many ways, especially through the harvest of fish, marine mammals, and seabirds. The spatial characteristics of this interaction are often depicted in terms of subsistence use areas: the places where harvests and associated travel occur. Another way to consider the interaction is to examine the areas where harvested species range during their lifecycle or annual migratory path. In this paper, we compare seasonal subsistence use areas, lifetime subsistence use areas, and "calorie-sheds," or the area over which harvested species range. Each perspective offers useful information concerning not only the nature of human-environment interactions but also the scope for potential conflict with other human activity and the means by which such conflicts could be reduced, avoided, or otherwise addressed. Seasonal subsistence use areas can be used to manage short-term activities, such as seasonal vessel traffic during community re-supply. Lifetime subsistence use areas indicate the area required to allow hunters and fishers the flexibility to adjust to interannual variability and perhaps to adapt to a changing environment. Calorie-sheds indicate the areas about which a community may be concerned due to potential impacts on the species they harvest.

Female employment reduces fertility in rural Senegal.

Directory of Open Access Journals (Sweden)

Goedele Van den Broeck

Full Text Available Economic growth and modernization of society are generally associated with fertility rate decreases but which forces trigger this is unclear. In this paper we assess how fertility changes with increased labor market participation of women in rural Senegal. Evidence from high-income countries suggests that higher female employment rates lead to reduced fertility rates but evidence from developing countries at an early stage of demographic transition is largely absent. We concentrate on a rural area in northern Senegal where a recent boom in horticultural exports has been associated with a sudden increase in female off-farm employment. Using survey data we show that employed women have a significantly higher age at marriage and at first childbirth, and significantly fewer children. As causal identification strategy we use instrumental variable and difference-in-differences estimations, combined with propensity score matching. We find that female employment reduces the number of children per woman by 25%, and that this fertility-reducing effect is as large for poor as for non-poor women and larger for illiterate than for literate women. Results imply that female employment is a strong instrument for empowering rural women, reducing fertility rates and accelerating the demographic transition in poor countries. The effectiveness of family planning programs can increase if targeted to areas where female employment is increasing or to female employees directly because of a higher likelihood to reach women with low-fertility preferences. Our results show that changes in fertility preferences not necessarily result from a cultural evolution but can also be driven by sudden and individual changes in economic opportunities.

Reduced cortical thickness and increased surface area in antisocial personality disorder.

Science.gov (United States)

Jiang, Weixiong; Li, Gang; Liu, Huasheng; Shi, Feng; Wang, Tao; Shen, Celina; Shen, Hui; Lee, Seong-Whan; Hu, Dewen; Wang, Wei; Shen, Dinggang

2016-11-19

Antisocial personality disorder (ASPD), one of whose characteristics is high impulsivity, is of great interest in the field of brain structure and function. However, little is known about possible impairments in the cortical anatomy in ASPD, in terms of cortical thickness (CTh) and surface area (SA), as well as their possible relationship with impulsivity. In this neuroimaging study, we first investigated the changes of CTh and SA in ASPD patients, in comparison to those of healthy controls, and then performed correlation analyses between these measures and the ability of impulse control. We found that ASPD patients showed thinner cortex while larger SA in several specific brain regions, i.e., bilateral superior frontal gyrus (SFG), orbitofrontal and triangularis, insula cortex, precuneus, middle frontal gyrus (MFG), middle temporal gyrus (MTG), and left bank of superior temporal sulcus (STS). In addition, we also found that the ability of impulse control was positively correlated with CTh in the SFG, MFG, orbitofrontal cortex (OFC), pars triangularis, superior temporal gyrus (STG), and insula cortex. To our knowledge, this study is the first to reveal simultaneous changes in CTh and SA in ASPD, as well as their relationship with impulsivity. These cortical structural changes may introduce uncontrolled and callous behavioral characteristic in ASPD patients, and these potential biomarkers may be very helpful in understanding the pathomechanism of ASPD. Copyright © 2016 IBRO. Published by Elsevier Ltd. All rights reserved.

Passerine birds breeding under chronic noise experience reduced fitness.

Directory of Open Access Journals (Sweden)

Julia Schroeder

Full Text Available BACKGROUND: Fitness in birds has been shown to be negatively associated with anthropogenic noise, but the underlying mechanisms remain obscure. It is however crucial to understand the mechanisms of how urban noise impinges on fitness to obtain a better understanding of the role of chronic noise in urban ecology. Here, we examine three hypotheses on how noise might reduce reproductive output in passerine birds: (H1 by impairing mate choice, (H2 by reducing territory quality and (H3 by impeding chick development. METHODOLOGY/PRINCIPAL FINDINGS: We used long-term data from an island population of house sparrows, Passer domesticus, in which we can precisely estimate fitness. We found that nests in an area affected by the noise from large generators produced fewer young, of lower body mass, and fewer recruits, even when we corrected statistically for parental genetic quality using a cross-fostering set-up, supporting H3. Also, individual females provided their young with food less often when they bred in the noisy area compared to breeding attempts by the same females elsewhere. Furthermore, we show that females reacted flexibly to increased noise levels by adjusting their provisioning rate in the short term, which suggests that noise may be a causal factor that reduces reproductive output. We rejected H1 and H2 because nestbox occupancy, parental body mass, age and reproductive investment did not differ significantly between noisy and quiet areas. CONCLUSIONS/SIGNIFICANCE: OUR RESULTS SUGGEST A PREVIOUSLY UNDESCRIBED MECHANISM TO EXPLAIN HOW ENVIRONMENTAL NOISE CAN REDUCE FITNESS IN PASSERINE BIRDS: by acoustically masking parent-offspring communication. More importantly, using a cross-fostering set-up, our results demonstrate that birds breeding in a noisy environment experience significant fitness costs. Chronic noise is omnipresent around human habitation and may produces similar fitness consequences in a wide range of urban bird species.

Reducing employee travelling time through smart commuting

International Nuclear Information System (INIS)

Rahman, A N N A; Yusoff, Z M; Aziz, I S; Omar, D

2014-01-01

Extremely congested roads will definitely delay the arrival time of each trip.This certainly impacted the journey of employees. Tardiness at the workplace has become a perturbing issue for companies where traffic jams are the most common worker excuses. A depressing consequence on daily life and productivity of the employee occurs. The issues of commuting distance between workplace and resident area become the core point of this research. This research will emphasize the use of Geographical Information System (GIS) technique to explore the distance parameter to the employment area and will focus on the accessibility pattern of low-cost housing. The research methodology consists of interview sessions and a questionnaire to residents of low-cost housing areas in Melaka Tengah District in Malaysia. The combination of these processes will show the criteria from the selected parameter for each respondent from their resident area to the employment area. This will further help in the recommendation of several options for a better commute or improvement to the existing routes and public transportations system. Thus enhancing quality of life for employees and helping to reduce stress, decrease lateness, absenteeism and improving productivity in workplace

Reducing employee travelling time through smart commuting

Science.gov (United States)

Rahman, A. N. N. A.; Yusoff, Z. M.; Aziz, I. S.; Omar, D.

2014-02-01

Extremely congested roads will definitely delay the arrival time of each trip.This certainly impacted the journey of employees. Tardiness at the workplace has become a perturbing issue for companies where traffic jams are the most common worker excuses. A depressing consequence on daily life and productivity of the employee occurs. The issues of commuting distance between workplace and resident area become the core point of this research. This research will emphasize the use of Geographical Information System (GIS) technique to explore the distance parameter to the employment area and will focus on the accessibility pattern of low-cost housing. The research methodology consists of interview sessions and a questionnaire to residents of low-cost housing areas in Melaka Tengah District in Malaysia. The combination of these processes will show the criteria from the selected parameter for each respondent from their resident area to the employment area. This will further help in the recommendation of several options for a better commute or improvement to the existing routes and public transportations system. Thus enhancing quality of life for employees and helping to reduce stress, decrease lateness, absenteeism and improving productivity in workplace.

Does Zoning Winter Recreationists Reduce Recreation Conflict?

Science.gov (United States)

Miller, Aubrey D.; Vaske, Jerry J.; Squires, John R.; Olson, Lucretia E.; Roberts, Elizabeth K.

2017-01-01

Parks and protected area managers use zoning to decrease interpersonal conflict between recreationists. Zoning, or segregation, of recreation—often by non-motorized and motorized activity—is designed to limit physical interaction while providing recreation opportunities to both groups. This article investigated the effectiveness of zoning to reduce recreation conflict in the Vail Pass Winter Recreation Area in Colorado, USA. Despite a zoning management system, established groomed travel routes were used by both non-motorized recreationists (backcountry skiers, snowboarders, snowshoers) and motorized recreationists (snowmobilers). We hypothesized that persistent recreation conflict reported by non-motorized recreationists was the result of recreation occurring in areas of mixed non-motorized and motorized use, mostly along groomed routes. We performed a geospatial analysis of recreation [from Global Positioning System (GPS) points, n = 1,233,449] in the Vail Pass Winter Recreation Area to identify areas of mixed non-motorized and motorized use. We then surveyed non-motorized recreationists ( n = 199) to test whether reported conflict is higher for respondents who traveled in areas of mixed-use, compared with respondents traveling outside areas of mixed-use. Results from the geospatial analysis showed that only 0.7 % of the Vail Pass Winter Recreation Area contained recreation from both groups, however that area contained 14.8 % of all non-motorized recreation and 49.1 % of all motorized recreation. Survey analysis results showed higher interpersonal conflict for all five standard conflict variables among non-motorized respondents who traveled in areas of mixed-use, compared with those traveling outside mixed-use areas. Management implications and recommendations for increasing the effectiveness of zoning are provided.

Significant association between sulfate-reducing bacteria and uranium-reducing microbial communities as revealed by a combined massively parallel sequencing-indicator species approach.

Science.gov (United States)

Cardenas, Erick; Wu, Wei-Min; Leigh, Mary Beth; Carley, Jack; Carroll, Sue; Gentry, Terry; Luo, Jian; Watson, David; Gu, Baohua; Ginder-Vogel, Matthew; Kitanidis, Peter K; Jardine, Philip M; Zhou, Jizhong; Criddle, Craig S; Marsh, Terence L; Tiedje, James M

2010-10-01

Massively parallel sequencing has provided a more affordable and high-throughput method to study microbial communities, although it has mostly been used in an exploratory fashion. We combined pyrosequencing with a strict indicator species statistical analysis to test if bacteria specifically responded to ethanol injection that successfully promoted dissimilatory uranium(VI) reduction in the subsurface of a uranium contamination plume at the Oak Ridge Field Research Center in Tennessee. Remediation was achieved with a hydraulic flow control consisting of an inner loop, where ethanol was injected, and an outer loop for flow-field protection. This strategy reduced uranium concentrations in groundwater to levels below 0.126 μM and created geochemical gradients in electron donors from the inner-loop injection well toward the outer loop and downgradient flow path. Our analysis with 15 sediment samples from the entire test area found significant indicator species that showed a high degree of adaptation to the three different hydrochemical-created conditions. Castellaniella and Rhodanobacter characterized areas with low pH, heavy metals, and low bioactivity, while sulfate-, Fe(III)-, and U(VI)-reducing bacteria (Desulfovibrio, Anaeromyxobacter, and Desulfosporosinus) were indicators of areas where U(VI) reduction occurred. The abundance of these bacteria, as well as the Fe(III) and U(VI) reducer Geobacter, correlated with the hydraulic connectivity to the substrate injection site, suggesting that the selected populations were a direct response to electron donor addition by the groundwater flow path. A false-discovery-rate approach was implemented to discard false-positive results by chance, given the large amount of data compared.

Pest management strategies: Area-wide and conventional

International Nuclear Information System (INIS)

Lindquist, D.A.

2000-01-01

part of the cost of an area-wide programme will be fighting the target pest away from the commercial production - before the commercial crops are susceptible - on wild or alternate hosts or abandoned orchards, untreated host plants in homeowners' gardens, etc. In most cases, area-wide insect control will be the responsibility of a separate organisation hired by the producers. A separate organisation can plan an aggressive offense against the target pest population over the entire area. High technology systems can be effectively utilised to plan the population management programme. Included will be satellite imagery to detect alternate hosts, sensitive methods to detect movement of the pest populations, computer programmes to predict changes in the pest insect population based on biological parameters, a systems approach to utilise natural enemies on an area-wide basis, genetic analysis to detect the development of resistance and utilisation of systems to delay the development of resistance over the total area. Further, area-wide programmes encourage the use of specialised methods of insect control that are not effective or are not used on a farm by farm basis. These include the sterile insect technique (SIT), male annihilation, inundative releases of parasites, mating inhibitors, large-scale trap cropping with very attractive plants, treatment of alternate hosts on public lands and hosts in private gardens, etc. The objective of area-wide control is to reduce the pest population within the target area to a non-economic level. This is accomplished by attacking the entire insect pest population in the target area. Conventional insect control attempts to protect the plant or animal, is carried out by individual producers over a small area with little planning, is short-term, low technology and is a reactive (defense) approach to insect control. Area-wide insect control attempts to reduce the pest population to a non-economic level over a large area involving many

Tank Focus Area pretreatment activities

International Nuclear Information System (INIS)

McGinnis, C.P.; Welch, T.D.; Manke, K.L.

1997-01-01

Plans call for the high-level wastes to be retrieved from the tanks and immobilized in a stable waste form suitable for long-term isolation. Chemistry and chemical engineering operations are required to retrieve the wastes, to condition the wastes for subsequent steps, and to reduce the costs of the waste management enterprise. Pretreatment includes those processes between retrieval and immobilization, and includes preparation of suitable feed material for immobilization and separations to partition the waste into streams that yield lower life-cycle costs. Some of the technologies being developed by the Tank Focus Area (TFA) to process these wastes are described. These technologies fall roughly into three areas: (1) solid/liquid separation (SLS), (2) sludge pretreatment, and (3) supernate pretreatment

Incentives for reducing emissions in Krakow

International Nuclear Information System (INIS)

Uberman, R.; Pierce, B.; Lazecki, A.

1994-01-01

This effort is identifying, specific incentives that may be used by Krakow city officials to encourage, residents to change the way they heat their homes and businesses in order to reduce pollution. This paper describes the incentives study for converting small coal or coke-fired boilers to gas in the Old Town area. A similar study looked at incentives for expanding the district heating system and future analyses will be performed for home stove options

Identification of active erosion areas and areas at risk by remote sensing: an example in the Esera Isabena watershed, Central Spanish Pyrenees

International Nuclear Information System (INIS)

Alatorre, L. C.; Begueria, S.; Vicente Serrano, S. M.

2009-01-01

The identification of eroded areas at basin scale can be very useful for environmental planning and can help to reduce land degradation and sediments yield. In this paper remote sensing technique are used to discriminate eroded areas and areas at risk in a badlands landscape developed on Eocene marls. In the Esera Isabena watershed (Spanish Pyrenees). The spatial distribution, the scarce vegetal cover and the high level of erosion let a good visual and digital discrimination of badlands, as opposed to other land covers and surfaces. A maximum likelihood supervised method was used to discriminate heavily eroded areas (badlands) from scarce or densely vegetated lands. the classification distance was used to obtain thresholds for eroded areas and areas at risk. Two error statistics (sensitivity and specificity), where used to determine the most adequate threshold values. The resulting map shows that most areas at risk are located surrounding the badlands areas. (Author) 8 refs.

Identification of active erosion areas and areas at risk by remote sensing: an example in the Esera Isabena watershed, Central Spanish Pyrenees

Energy Technology Data Exchange (ETDEWEB)

Alatorre, L. C.; Begueria, S.; Vicente Serrano, S. M.

2009-07-01

The identification of eroded areas at basin scale can be very useful for environmental planning and can help to reduce land degradation and sediments yield. In this paper remote sensing technique are used to discriminate eroded areas and areas at risk in a badlands landscape developed on Eocene marls. In the Esera Isabena watershed (Spanish Pyrenees). The spatial distribution, the scarce vegetal cover and the high level of erosion let a good visual and digital discrimination of badlands, as opposed to other land covers and surfaces. A maximum likelihood supervised method was used to discriminate heavily eroded areas (badlands) from scarce or densely vegetated lands. the classification distance was used to obtain thresholds for eroded areas and areas at risk. Two error statistics (sensitivity and specificity), where used to determine the most adequate threshold values. The resulting map shows that most areas at risk are located surrounding the badlands areas. (Author) 8 refs.

Speech-associated gestures, Broca’s area, and the human mirror system

Science.gov (United States)

Skipper, Jeremy I.; Goldin-Meadow, Susan; Nusbaum, Howard C.; Small, Steven L

2009-01-01

Speech-associated gestures are hand and arm movements that not only convey semantic information to listeners but are themselves actions. Broca’s area has been assumed to play an important role both in semantic retrieval or selection (as part of a language comprehension system) and in action recognition (as part of a “mirror” or “observation–execution matching” system). We asked whether the role that Broca’s area plays in processing speech-associated gestures is consistent with the semantic retrieval/selection account (predicting relatively weak interactions between Broca’s area and other cortical areas because the meaningful information that speech-associated gestures convey reduces semantic ambiguity and thus reduces the need for semantic retrieval/selection) or the action recognition account (predicting strong interactions between Broca’s area and other cortical areas because speech-associated gestures are goal-direct actions that are “mirrored”). We compared the functional connectivity of Broca’s area with other cortical areas when participants listened to stories while watching meaningful speech-associated gestures, speech-irrelevant self-grooming hand movements, or no hand movements. A network analysis of neuroimaging data showed that interactions involving Broca’s area and other cortical areas were weakest when spoken language was accompanied by meaningful speech-associated gestures, and strongest when spoken language was accompanied by self-grooming hand movements or by no hand movements at all. Results are discussed with respect to the role that the human mirror system plays in processing speech-associated movements. PMID:17533001

When roads appear jaguars decline: Increased access to an Amazonian wilderness area reduces potential for jaguar conservation.

Science.gov (United States)

Espinosa, Santiago; Celis, Gerardo; Branch, Lyn C

2018-01-01

Roads are a main threat to biodiversity conservation in the Amazon, in part, because roads increase access for hunters. We examine how increased landscape access by hunters may lead to cascading effects that influence the prey community and abundance of the jaguar (Panthera onca), the top Amazonian terrestrial predator. Understanding such ecological effects originating from anthropogenic actions is essential for conservation and management of wildlife populations in areas undergoing infrastructure development. Our study was conducted in Yasuní Biosphere Reserve, the protected area with highest potential for jaguar conservation in Ecuador, and an area both threatened by road development and inhabited by indigenous groups dependent upon bushmeat. We surveyed prey and jaguar abundance with camera traps in four sites that differed in accessibility to hunters and used site occupancy and spatially explicit capture-recapture analyses to evaluate prey occurrence and estimate jaguar density, respectively. Higher landscape accessibility to hunters was linked with lower occurrence and biomass of game, particularly white-lipped peccary (Tayassu pecari) and collared peccary (Pecari tajacu), the primary game for hunters and prey for jaguars. Jaguar density was up to 18 times higher in the most remote site compared to the most accessible site. Our results provide a strong case for the need to: 1) consider conservation of large carnivores and other wildlife in policies about road construction in protected areas, 2) coordinate conservation initiatives with local governments so that development activities do not conflict with conservation objectives, and 3) promote development of community-based strategies for wildlife management that account for the needs of large carnivores.

Reducing microscopy-based malaria misdiagnosis in a low ...

African Journals Online (AJOL)

In this paper we report on the outcomes of a simple intervention that utilized a social entrepreneurship approach (SEA) to reduce misdiagnosis associated with hospital-based microscopy of malaria in a low-transmission area of rural Tanzania. A pre-post assessment was conducted on patients presenting to the hospital ...

Area overhead analysis of SEF: A design methodology for tolerating SEU

International Nuclear Information System (INIS)

Blaquiere, Y.; Savaria, Y.

1987-01-01

Soft-Error filtering (SEF) is a design methodology proposed recently for implementing machines tolerant to SEU. This paper deals mainly with the evaluation and the reduction of the area overhead brought by SEF. A new shift register filtering latch configuration is proposed. The use of this latch, optimized for minimum area, reduces the area overhead by a factor of 2.6, when compared with latches optimized for time performance. A detailed analysis of the area overhead with SEF implemented on two relatively complex machines produced the following results: a SEF version of the 6800 microprocessor would require an area overhead varying between 12% and 69% depending on the SEF latch used and, a SEF version of the RISCII microprocessor would result in a 38.8% area overhead. An analysis of the cost of implementing the Hamming error correcting code on a register array is presented and this cost is compared with that of implementing SEU tolerance directly with SEF. Finally, a hybrid approach is proposed where a large register array is protected by an error correcting code whereas the isolated latches are replaced by filtering latches. This hybrid approach reduces the area overhead to 18.8% for the RISCII architecture

Prenatal ethanol exposure modifies locomotor activity and induces selective changes in Met-enk expression in adolescent rats.

Science.gov (United States)

Abate, P; Reyes-Guzmán, A C; Hernández-Fonseca, K; Méndez, M

2017-04-01

Several studies suggest that prenatal ethanol exposure (PEE) facilitates ethanol intake. Opioid peptides play a main role in ethanol reinforcement during infancy and adulthood. However, PEE effects upon motor responsiveness elicited by an ethanol challenge and the participation of opioids in these actions remain to be understood. This work assessed the susceptibility of adolescent rats to prenatal and/or postnatal ethanol exposure in terms of behavioral responses, as well as alcohol effects on Met-enk expression in brain areas related to drug reinforcement. Motor parameters (horizontal locomotion, rearings and stereotyped behaviors) in pre- and postnatally ethanol-challenged adolescents were evaluated. Pregnant rats received ethanol (2g/kg) or water during gestational days 17-20. Adolescents at postnatal day 30 (PD30) were tested in a three-trial activity paradigm (habituation, vehicle and drug sessions). Met-enk content was quantitated by radioimmunoassay in several regions: ventral tegmental area [VTA], nucleus accumbens [NAcc], prefrontal cortex [PFC], substantia nigra [SN], caudate-putamen [CP], amygdala, hypothalamus and hippocampus. PEE significantly reduced rearing responses. Ethanol challenge at PD30 decreased horizontal locomotion and showed a tendency to reduce rearings and stereotyped behaviors. PEE increased Met-enk content in the PFC, CP, hypothalamus and hippocampus, but did not alter peptide levels in the amygdala, VTA and NAcc. These findings suggest that PEE selectively modifies behavioral parameters at PD30 and induces specific changes in Met-enk content in regions of the mesocortical and nigrostriatal pathways, the hypothalamus and hippocampus. Prenatal and postnatal ethanol actions on motor activity in adolescents could involve activation of specific neural enkephalinergic pathways. Copyright © 2016 Elsevier Ltd. All rights reserved.

Large-area self-assembled reduced graphene oxide/electrochemically exfoliated graphene hybrid films for transparent electrothermal heaters

Science.gov (United States)

Sun, Hongyan; Chen, Ding; Ye, Chen; Li, Xinming; Dai, Dan; Yuan, Qilong; Chee, Kuan W. A.; Zhao, Pei; Jiang, Nan; Lin, Cheng-Te

2018-03-01

Graphene shows great promise as a high-efficiency electrothermal film for flexible transparent defoggers/defrosters. However, it remains a great challenge to achieve a good balance between the production cost and the properties of graphene films. Here, we proposed a cost-effective self-assembly method to fabricate high-performance, large-area graphene oxide/electrochemically exfoliated graphene hybrid films for heater applications. The self-assembled graphene hybrid films with the area of 20 × 20 cm2 could be transferred onto arbitrary substrates with nonplanar surfaces and simply patterned with the hard mask. After reduction by hydrogen iodide vapor followed by 800 °C thermal treatment, the hybrid films with the transmittance of 76.2% exhibit good heating characteristics and defogging performance, which reach a saturation temperature of up to 127.5 °C when 40 V was applied for 60 s.

Autism: reduced connectivity between cortical areas involved in face expression, theory of mind, and the sense of self.

Science.gov (United States)

Cheng, Wei; Rolls, Edmund T; Gu, Huaguang; Zhang, Jie; Feng, Jianfeng

2015-05-01

Whole-brain voxel-based unbiased resting state functional connectivity was analysed in 418 subjects with autism and 509 matched typically developing individuals. We identified a key system in the middle temporal gyrus/superior temporal sulcus region that has reduced cortical functional connectivity (and increased with the medial thalamus), which is implicated in face expression processing involved in social behaviour. This system has reduced functional connectivity with the ventromedial prefrontal cortex, which is implicated in emotion and social communication. The middle temporal gyrus system is also implicated in theory of mind processing. We also identified in autism a second key system in the precuneus/superior parietal lobule region with reduced functional connectivity, which is implicated in spatial functions including of oneself, and of the spatial environment. It is proposed that these two types of functionality, face expression-related, and of one's self and the environment, are important components of the computations involved in theory of mind, whether of oneself or of others, and that reduced connectivity within and between these regions may make a major contribution to the symptoms of autism. © The Author (2015). Published by Oxford University Press on behalf of the Guarantors of Brain.

Project Work Plan: Hanford 100-D Area Treatability Demonstration - In Situ Biostimulation for Reducing Barrier

Energy Technology Data Exchange (ETDEWEB)

Fruchter, Jonathan S.; Truex, Michael J.; Vermeul, Vince R.; Long, Philip E.

2006-05-31

This work plan supports a new, integrated approach to accelerate cleanup of chromium in the Hanford 100 Areas. This new approach will provide supplemental treatment upgradient of the ISRM barrier by directly treating chromium and other oxidizing species in groundwater (i.e., nitrate and dissolved oxygen), thereby increasing the longevity of the ISRM barrier and protecting the ecological receptors and human health at the river boundary.

Alpha-contingent EEG feedback reduces SPECT rCBF variability

DEFF Research Database (Denmark)

McLaughlin, Thomas; Steinberg, Bruce; Mulholland, Thomas

2005-01-01

EEG feedback methods, which link the occurrence of alpha to the presentation of repeated visual stimuli, reduce the relative variability of subsequent, alpha-blocking event durations. The temporal association between electro-cortical field activation and regional cerebral blood flow (rCBF) led us...... to investigate whether the reduced variability of alpha-blocking durations with feedback is associated with a reduction in rCBF variability. Reduced variability in the rCBF response domain under EEG feedback control might have methodological implications for future brain-imaging studies. Visual stimuli were...... to quantify the variance-reducing effects of ACS across multiple, distributed areas of the brain. Both EEG and rCBF measures demonstrated decreased variability under ACS. This improved control was seen for localized as well as anatomically distributed rCBF measures....

A review on power reducing methods of neural recording amplifiers

Directory of Open Access Journals (Sweden)

samira mehdipour

2016-10-01

Full Text Available Implantable multi-channel neural recording Microsystems comprise a large number of neural amplifiers, that can affect the overall power consumption and chip area of the analog part of the system.power, noise, size and dc offset are the main challenge faced by designers. Ideally the output of the opamp should be at zero volts when the inputs are grounded.In reality the input terminals are at slightly different dc potentials.The input offset voltage is defined as the voltage that must be applied between the two input terminals of the opamp to obtain zero volts at the output. Amplifier must have capability to reject this dc offset. First method that uses a capacitor feedback network with ac coupling of input devices to reject the offset is very popular in designs.very small low-cutoff frequency.The second method employs a closed-loop resistive feedback and electrode capacitance to form a highpass filter.Moreover,The third method adopts the symmetric floating resistor the feedback path of low noise amplifier to achieve low-frequency cutoff and rejects DC offset voltage. .In some application we can use folded cascade topology.The telescopic topology is a good candidate in terms of providing large gain and phase margin while dissipating small power. the cortical VLSI neuron model reducing power consumption of circuits.Power distribution is the best way to reduce power, noise and silicon area. The total power consumption of the amplifier array is reduced by applying the partial OTA sharing technique. The silicon area is reduced as a benefit of sharing the bulky capacitor.

Study on mutual perception between the people living in the area around a nuclear power plant and in a power-consuming area

International Nuclear Information System (INIS)

Ueda, Yoshitaka; Sakai, Yukimi; Kita, Hiroyuki

2009-01-01

At first we conducted an interview survey of the urban residents, in order to gather various opinions about the area around a nuclear power plant. Then we conducted a questionnaires survey of the urban area to investigate how many people had the same opinions as we had extracted from the interview survey. We also compared these results with the site residents opinion which had been reported in other research. These results show that the urban residents tend to overestimate the risk perception of the local area and the local residents' anxiety about the nuclear power plant, and to underestimate the relationship between the electric company operating nuclear power plant and the local residents. These results also show that the local residents tend to underestimate the urban residents' knowledge of a nuclear power plant, and to take a pessimistic view of the urban residents' perception about the local residents. In order to reduce the sense of unfairness and dissatisfaction and to promote public acceptance of nuclear energy, it is desirable to reduce these misunderstanding and misconception. To this end, this study suggests that it is necessary to make them notice the misconception and grow mutual understanding by exchanging information of the opinions and the situations in each area. (author)

Carbon benefits from protected areas in the conterminous United States

Science.gov (United States)

Daolan Zheng; Linda S. Heath; Mark J. Ducey

2013-01-01

Conversion of forests to other land cover or land use releases the carbon stored in the forests and reduces carbon sequestration potential of the land. The rate of forest conversion could be reduced by establishing protected areas for biological diversity and other conservation goals. The purpose of this study is to quantify the efficiency and potential of forest land...

Effects of Intranasal Oxytocin on the Blood Oxygenation Level-Dependent Signal in Food Motivation and Cognitive Control Pathways in Overweight and Obese Men.

Science.gov (United States)

Plessow, Franziska; Marengi, Dean A; Perry, Sylvia K; Felicione, Julia M; Franklin, Rachel; Holmes, Tara M; Holsen, Laura M; Makris, Nikolaos; Deckersbach, Thilo; Lawson, Elizabeth A

2018-02-01

Recent research indicates that the hypothalamic neuropeptide hormone oxytocin is a key central nervous system factor in the regulation of food intake and weight. However, the mechanisms underlying the anorexigenic effects of oxytocin in humans are unknown and critical to study to consider oxytocin as a neurohormonal weight loss treatment. We performed a randomized, double-blind, placebo-controlled crossover study with single-dose intranasal oxytocin (24 IU) in ten overweight or obese, otherwise healthy men. Following oxytocin/placebo administration, participants completed an established functional magnetic resonance imaging food motivation paradigm. We hypothesized that oxytocin would reduce the blood oxygenation level-dependent (BOLD) signal to high-calorie food vs non-food visual stimuli in the ventral tegmental area (VTA), the origin of the mesolimbic dopaminergic reward system. Following oxytocin administration, compared to placebo, participants showed bilateral VTA hypoactivation to high-calorie food stimuli. A secondary exploratory whole-brain analysis revealed hypoactivation in additional hedonic (orbitofrontal cortex, insula, globus pallidus, putamen, hippocampus, and amygdala) and homeostatic (hypothalamus) food motivation and hyperactivation in cognitive control (anterior cingulate and frontopolar cortex) brain regions following oxytocin administration vs placebo. Oxytocin administration reduces the BOLD signal in reward-related food motivation brain regions, providing a potential neurobiological mechanism for the anorexigenic oxytocin effects in humans. Furthermore, our data indicate that oxytocin administration reduces activation in homeostatic and increases activation in cognitive control brain regions critically involved in regulating food intake and resolving affective conflict, respectively. Future studies are required to link these changes in brain activation to oxytocin effects on food intake and weight.

The anorexic agents, sibutramine and fenfluramine, depress GABAB-induced inhibitory postsynaptic potentials in rat mesencephalic dopaminergic cells

Science.gov (United States)

Ledonne, Ada; Sebastianelli, Luca; Federici, Mauro; Bernardi, Giorgio; Mercuri, Nicola Biagio

2009-01-01

Background and purpose Nutrition is the result of a complex interaction among environmental, homeostatic and reward-related processes. Accumulating evidence supports key roles for the dopaminergic neurons of the ventral midbrain in regulating feeding behaviour. For this reason, in the present study, we have investigated the electrophysiological effects of two centrally acting anorexic agents, fenfluramine and sibutramine, on these cells. Experimental approach Rat midbrain slices were used to make intracellular recordings from dopaminergic neurons of the substantia nigra and the ventral tegmental area. Gamma-aminobutyric acid (GABA)-mediated synaptic transmission was assessed from the inhibitory postsynaptic potentials (IPSPs) mediated by GABAA and GABAB receptors. Key results Fenfluramine and sibutramine reduced, concentration-dependently, the GABAB IPSPs, without affecting the GABAA-mediated potentials. This effect is presynaptic, as postsynaptic membrane responses induced by application of a GABAB receptor agonist, baclofen, were not affected by the two drugs. Furthermore, the selective 5-hydroxytriptamine 1B (5-HT1B) receptor antagonist, SB216641, blocked the reduction of GABAB IPSPs caused by fenfluramine and sibutramine, indicating that the receptor mediating this effect is 5-HT1B. Conclusions and implications Two anorexic agents, fenfluramine and sibutramine, induced the activation of 5-HT1B receptors located on presynaptic GABAergic terminals, thus reducing the release of GABA. This action can alter the strength of synaptic afferents that modify the activity of dopaminergic neurons, inducing neuronal excitation. Our results reveal an additional mechanism of action for fenfluramine and sibutramine that might contribute to reducing food intake, by influencing the pleasurable and motor aspects of feeding behaviour. PMID:19298257

Perturbations in Effort-Related Decision-Making Driven by Acute Stress and Corticotropin-Releasing Factor.

Science.gov (United States)

Bryce, Courtney A; Floresco, Stan B

2016-07-01

Acute stress activates numerous systems in a coordinated effort to promote homeostasis, and can exert differential effects on mnemonic and cognitive functions depending on a myriad of factors. Stress can alter different forms of cost/benefit decision-making, yet the mechanisms that drive these effects, remain unclear. In the present study, we probed how corticotropin-releasing factor (CRF) may contribute to stress-induced alterations in cost/benefit decision-making, using an task where well-trained rats chose between a low effort/low reward lever (LR; two pellets) and a high effort/high reward lever (HR; four pellets), with the effort requirement increasing over a session (2, 5, 10, and 20 presses). One-hour restraint stress markedly reduced preference for the HR option, but this effect was attenuated by infusions of the CRF antagonist, alpha-helical CRF. Conversely, central CRF infusion mimicked the effect of stress on decision-making, as well as increased decision latencies and reduced response vigor. CRF infusions did not alter preference for larger vs smaller rewards, but did reduce responding for food delivered on a progressive ratio, suggesting that these treatments may amplify perceived effort costs that may be required to obtain rewards. CRF infusions into the ventral tegmental area recapitulated the effect of central CRF treatment and restraint on choice behavior, suggesting that these effects may be mediated by perturbations in dopamine transmission. These findings highlight the involvement of CRF in regulating effort-related decisions and suggest that increased CRF activity may contribute to motivational impairments and abnormal decision-making associated with stress-related psychiatric disorders such as depression.

Altered prefrontal correlates of monetary anticipation and outcome in chronic pain.

Science.gov (United States)

Martucci, Katherine T; Borg, Nicholas; MacNiven, Kelly H; Knutson, Brian; Mackey, Sean C

2018-04-04

Chronic pain may alter both affect- and value-related behaviors, which represents a potentially treatable aspect of chronic pain experience. Current understanding of how chronic pain influences the function of brain reward systems, however, is limited. Using a monetary incentive delay task and functional magnetic resonance imaging (fMRI), we measured neural correlates of reward anticipation and outcomes in female participants with the chronic pain condition of fibromyalgia (N = 17) and age-matched, pain-free, female controls (N = 15). We hypothesized that patients would demonstrate lower positive arousal, as well as altered reward anticipation and outcome activity within corticostriatal circuits implicated in reward processing. Patients demonstrated lower arousal ratings as compared with controls, but no group differences were observed for valence, positive arousal, or negative arousal ratings. Group fMRI analyses were conducted to determine predetermined region of interest, nucleus accumbens (NAcc) and medial prefrontal cortex (mPFC), responses to potential gains, potential losses, reward outcomes, and punishment outcomes. Compared with controls, patients demonstrated similar, although slightly reduced, NAcc activity during gain anticipation. Conversely, patients demonstrated dramatically reduced mPFC activity during gain anticipation-possibly related to lower estimated reward probabilities. Further, patients demonstrated normal mPFC activity to reward outcomes, but dramatically heightened mPFC activity to no-loss (nonpunishment) outcomes. In parallel to NAcc and mPFC responses, patients demonstrated slightly reduced activity during reward anticipation in other brain regions, which included the ventral tegmental area, anterior cingulate cortex, and anterior insular cortex. Together, these results implicate altered corticostriatal processing of monetary rewards in chronic pain.

Kiwifruit Non-Sugar Components Reduce Glycaemic Response to Co-Ingested Cereal in Humans

Directory of Open Access Journals (Sweden)

Suman Mishra

2017-10-01

Full Text Available Kiwifruit (KF effects on the human glycaemic response to co-ingested wheat cereal were determined. Participants (n = 20 consumed four meals in random order, all being made to 40 g of the same available carbohydrate, by adding kiwifruit sugars (KF sug; glucose, fructose, sucrose 2:2:1 to meals not containing KF. The meals were flaked wheat biscuit (WB+KFsug, WB+KF, WB+guar gum+KFsug, WB+guar gum+KF, that was ingested after fasting overnight. Blood glucose was monitored 3 h and hunger measured at 180 min post-meal using a visual analogue scale. KF and guar reduced postprandial blood glucose response amplitude, and prevented subsequent hypoglycaemia that occurred with WB+KFsug. The area between the blood glucose response curve and baseline from 0 to 180 min was not significantly different between meals, 0–120 min areas were significantly reduced by KF and/or guar. Area from 120 to 180 min was positive for KF, guar, and KF+guar, while the area for the WB meal was negative. Hunger at 180 min was significantly reduced by KF and/or guar when compared with WB. We conclude that KF components other than available carbohydrate may improve the glycaemic response profile to co-ingested cereal food.

Investigating the Potential of Ridesharing to Reduce Vehicle Emissions

Directory of Open Access Journals (Sweden)

Roozbeh Jalali

2017-06-01

Full Text Available As urban populations grow, cities need new strategies to maintain a good standard of living while enhancing services and infrastructure development. A key area for improving city operations and spatial layout is the transportation of people and goods. While conventional transportation systems (i.e., fossil fuel based are struggling to serve mobility needs for growing populations, they also represent serious environmental threats. Alternative-fuel vehicles can reduce emissions that contribute to local air pollution and greenhouse gases as mobility needs grow. However, even if alternative-powered vehicles were widely employed, road congestion would still increase. This paper investigates ridesharing as a mobility option to reduce emissions (carbon, particulates and ozone while accommodating growing transportation needs and reducing overall congestion. The potential of ridesharing to reduce carbon emissions from personal vehicles in Changsha, China, is examined by reviewing mobility patterns of approximately 8,900 privately-owned vehicles over two months. Big data analytics identify ridesharing potential among these drivers by grouping vehicles by their trajectory similarity. The approach includes five steps: data preprocessing, trip recognition, feature vector creation, similarity measurement and clustering. Potential reductions in vehicle emissions through ridesharing among a specific group of drivers are calculated and discussed. While the quantitative results of this analysis are specific to the population of Changsha, they provide useful insights for the potential of ridesharing to reduce vehicle emissions and the congestion expected to grow with mobility needs. Within the study area, ridesharing has the potential to reduce total kilometers driven by about 24% assuming a maximum distance between trips less than 10 kilometers, and schedule time less than 60 minutes. For a more conservative maximum trip distance of 2 kilometers and passenger

Effect of reducing cost sharing for outpatient care on children's inpatient services in Japan.

Science.gov (United States)

Kato, Hirotaka; Goto, Rei

2017-08-15

Assessing the impact of cost sharing on healthcare utilization is a critical issue in health economics and health policy. It may affect the utilization of different services, but is yet to be well understood. This paper investigates the effects of reducing cost sharing for outpatient services on hospital admissions by exploring a subsidy policy for children's outpatient services in Japan. Data were extracted from the Japanese Diagnosis Procedure Combination database for 2012 and 2013. A total of 366,566 inpatients from 1390 municipalities were identified. The impact of expanding outpatient care subsidy on the volume of inpatient care for 1390 Japanese municipalities was investigated using the generalized linear model with fixed effects. A decrease in cost sharing for outpatient care has no significant effect on overall hospital admissions, although this effect varies by region. The subsidy reduces the number of overall admissions in low-income areas, but increases it in high-income areas. In addition, the results for admissions by type show that admissions for diagnosis increase particularly in high-income areas, but emergency admissions and ambulatory-care-sensitive-condition admissions decrease in low-income areas. These results suggest that outpatient and inpatient services are substitutes in low-income areas but complements in high-income ones. Although the subsidy for children's healthcare would increase medical costs, it would not improve the health status in high-income areas. Nevertheless, it could lead to some health improvements in low-income areas and, to some extent, offset costs by reducing admissions in these regions.

Significant Association between Sulfate-Reducing Bacteria and Uranium-Reducing Microbial Communities as Revealed by a Combined Massively Parallel Sequencing-Indicator Species Approach▿ †

Science.gov (United States)

Cardenas, Erick; Wu, Wei-Min; Leigh, Mary Beth; Carley, Jack; Carroll, Sue; Gentry, Terry; Luo, Jian; Watson, David; Gu, Baohua; Ginder-Vogel, Matthew; Kitanidis, Peter K.; Jardine, Philip M.; Zhou, Jizhong; Criddle, Craig S.; Marsh, Terence L.; Tiedje, James M.

2010-01-01

Massively parallel sequencing has provided a more affordable and high-throughput method to study microbial communities, although it has mostly been used in an exploratory fashion. We combined pyrosequencing with a strict indicator species statistical analysis to test if bacteria specifically responded to ethanol injection that successfully promoted dissimilatory uranium(VI) reduction in the subsurface of a uranium contamination plume at the Oak Ridge Field Research Center in Tennessee. Remediation was achieved with a hydraulic flow control consisting of an inner loop, where ethanol was injected, and an outer loop for flow-field protection. This strategy reduced uranium concentrations in groundwater to levels below 0.126 μM and created geochemical gradients in electron donors from the inner-loop injection well toward the outer loop and downgradient flow path. Our analysis with 15 sediment samples from the entire test area found significant indicator species that showed a high degree of adaptation to the three different hydrochemical-created conditions. Castellaniella and Rhodanobacter characterized areas with low pH, heavy metals, and low bioactivity, while sulfate-, Fe(III)-, and U(VI)-reducing bacteria (Desulfovibrio, Anaeromyxobacter, and Desulfosporosinus) were indicators of areas where U(VI) reduction occurred. The abundance of these bacteria, as well as the Fe(III) and U(VI) reducer Geobacter, correlated with the hydraulic connectivity to the substrate injection site, suggesting that the selected populations were a direct response to electron donor addition by the groundwater flow path. A false-discovery-rate approach was implemented to discard false-positive results by chance, given the large amount of data compared. PMID:20729318

Intervention for reducing stigma: Assessing the influence of gender and knowledge.

Science.gov (United States)

Martínez-Zambrano, Francisco; García-Morales, Esther; García-Franco, Mar; Miguel, Jose; Villellas, Raul; Pascual, Gemma; Arenas, Otilia; Ochoa, Susana

2013-06-22

To evaluate the effectiveness in reducing social stigma of an intervention and to assess the influence of gender and knowledge. The program consisted in providing information and contact with users of mental health in order to reduce social stigma in the school environment. A total of 62 secondary school students (age 14-16 years) were evaluated with the Opinions on Mental Illness (OMI) questionnaire before and after the intervention. The subscales of the OMI were: authoritarianism, interpersonal etiology, benevolence, restrictiveness and negativism. The analysis was performed over the total sample, separating by gender and knowledge of someone with a mental disorder. t-test for repeated measures was used in the statistical analysis. All the OMI subscales showed a significant change after the intervention (P mental disorder presented significant changes in authoritarianism, interpersonal etiology, and negativism (P mental disorder improved in restrictiveness and authoritarianism (P mental disorders, reducing their levels of stigma. The intervention designed to reduce social stigma was effective, especially in the area of authoritarianism. The whole sample showed improved attitudes towards mental illness, although the areas were different depending on gender and knowledge.

Reduced prefrontal connectivity in psychopathy.

Science.gov (United States)

Motzkin, Julian C; Newman, Joseph P; Kiehl, Kent A; Koenigs, Michael

2011-11-30

Linking psychopathy to a specific brain abnormality could have significant clinical, legal, and scientific implications. Theories on the neurobiological basis of the disorder typically propose dysfunction in a circuit involving ventromedial prefrontal cortex (vmPFC). However, to date there is limited brain imaging data to directly test whether psychopathy may indeed be associated with any structural or functional abnormality within this brain area. In this study, we employ two complementary imaging techniques to assess the structural and functional connectivity of vmPFC in psychopathic and non-psychopathic criminals. Using diffusion tensor imaging, we show that psychopathy is associated with reduced structural integrity in the right uncinate fasciculus, the primary white matter connection between vmPFC and anterior temporal lobe. Using functional magnetic resonance imaging, we show that psychopathy is associated with reduced functional connectivity between vmPFC and amygdala as well as between vmPFC and medial parietal cortex. Together, these data converge to implicate diminished vmPFC connectivity as a characteristic neurobiological feature of psychopathy.

[Biological and neural bases of partner preferences in rodents: models to understand human pair bonds].

Science.gov (United States)

Coria-Avila, G A; Hernández-Aguilar, M E; Toledo-Cárdenas, R; García-Hernández, L I; Manzo, J; Pacheco, P; Miquel, M; Pfaus, J G

To analyse the biological and neural bases of partner preference formation in rodents as models to understand human pair bonding. Rodents are social individuals, capable of forming short- or long-lasting partner preferences that develop slowly by stimuli like cohabitation, or rapidly by stimuli like sex and stress. Dopamine, corticosteroids, oxytocin, vasopressin, and opioids form the neurochemical substrate for pair bonding in areas like the nucleus accumbens, the prefrontal cortex, the piriform cortex, the medial preoptic area, the ventral tegmental area and the medial amygdala, among others. Additional areas may participate depending on the nature of the conditioned stimuli by which and individual recognizes a preferred partner. Animal models help us understand that the capacity of an individual to display long-lasting and selective preferences depends on neural bases, selected throughout evolution. The challenge in neuroscience is to use this knowledge to create new solutions for mental problems associated with the incapacity of an individual to display a social bond, keep one, or cope with the disruption of a consolidated one.

Permeable Asphalt: A New Tool to Reduce Road Salt Contamination of Groundwater in Urban Areas.

Science.gov (United States)

Dietz, Michael E; Angel, Derek R; Robbins, Gary A; McNaboe, Lukas A

2017-03-01

Chloride contamination of groundwater in urban areas due to deicing is a well-documented phenomenon in northern climates. The objective of this study was to evaluate the effects of permeable pavement on degraded urban groundwater. Although low impact development practices have been shown to improve stormwater quality, no infiltration practice has been found to prevent road salt chlorides from entering groundwater. The few studies that have investigated chlorides in permeable asphalt have involved sampling directly beneath the asphalt; no research has looked more broadly at surrounding groundwater conditions. Monitoring wells were installed upgradient and downgradient of an 860 m 2 permeable asphalt parking lot at the University of Connecticut (Storrs, Connecticut). Water level and specific conductance were measured continuously, and biweekly samples were analyzed for chloride. Samples were also analyzed for sodium (Na), calcium (Ca), and magnesium (Mg). Analysis of variance analysis indicated a significantly (p monitoring revealed lower Cl concentrations downgradient than upgradient for the majority of the year. These results suggest that the use of permeable asphalt in impacted urban environments with high ambient chloride concentrations can be beneficial to shallow groundwater quality, although these results may not be generalizable to areas with low ambient chloride concentrations. © 2016, National Ground Water Association.

The effects of vibration-reducing gloves on finger vibration

Science.gov (United States)

Welcome, Daniel E.; Dong, Ren G.; Xu, Xueyan S.; Warren, Christopher; McDowell, Thomas W.

2015-01-01

Vibration-reducing (VR) gloves have been used to reduce the hand-transmitted vibration exposures from machines and powered hand tools but their effectiveness remains unclear, especially for finger protection. The objectives of this study are to determine whether VR gloves can attenuate the vibration transmitted to the fingers and to enhance the understanding of the mechanisms of how these gloves work. Seven adult male subjects participated in the experiment. The fixed factors evaluated include hand force (four levels), glove condition (gel-filled, air bladder, no gloves), and location of the finger vibration measurement. A 3-D laser vibrometer was used to measure the vibrations on the fingers with and without wearing a glove on a 3-D hand-arm vibration test system. This study finds that the effect of VR gloves on the finger vibration depends on not only the gloves but also their influence on the distribution of the finger contact stiffness and the grip effort. As a result, the gloves increase the vibration in the fingertip area but marginally reduce the vibration in the proximal area at some frequencies below 100 Hz. On average, the gloves reduce the vibration of the entire fingers by less than 3% at frequencies below 80 Hz but increase at frequencies from 80 to 400 Hz. At higher frequencies, the gel-filled glove is more effective at reducing the finger vibration than the air bladder-filled glove. The implications of these findings are discussed. Relevance to industry Prolonged, intensive exposure to hand-transmitted vibration can cause hand-arm vibration syndrome. Vibration-reducing gloves have been used as an alternative approach to reduce the vibration exposure. However, their effectiveness for reducing finger-transmitted vibrations remains unclear. This study enhanced the understanding of the glove effects on finger vibration and provided useful information on the effectiveness of typical VR gloves at reducing the vibration transmitted to the fingers. The new

Area law and vacuum reordering in harmonic networks

International Nuclear Information System (INIS)

Riera, A.; Latorre, J. I.

2006-01-01

We review a number of ideas related to area-law scaling of the geometric entropy from the point of view of condensed matter, quantum field theory, and quantum information. An explicit computation in arbitrary dimensions of the geometric entropy of the ground state of a discretized scalar free field theory shows the expected area law result. In this case, area-law scaling is a manifestation of a deeper reordering of the vacuum produced by majorization relations. Furthermore, the explicit control on all the eigenvalues of the reduced density matrix allows for a verification of entropy loss along the renormalization group trajectory driven by the mass term. A further result of our computation shows that single-copy entanglement also obeys area law scaling, majorization relations, and decreases along renormalization group flows

Respiratory gated lung CT using 320-row area detector CT

International Nuclear Information System (INIS)

Sakamoto, Ryo; Noma, Satoshi; Higashino, Takanori

2010-01-01

Three hundred and twenty-row Area Detector CT (ADCT) has made it possible to scan whole lung field with prospective respiratory gated wide volume scan. We evaluated whether the respiratory gated wide volume scan enables to reduce motion induced artifacts in the lung area. Helical scan and respiratory gated wide volume scan were performed in 5 patients and 10 healthy volunteers under spontaneous breathing. Significant reduction of motion artifact and superior image quality were obtained in respiratory gated scan in comparison with helical scan. Respiratory gated wide volume scan is an unique method using ADCT, and is able to reduce motion artifacts in lung CT scans of patients unable to suspend respiration in clinical scenes. (author)

The RED (reduce everyone's dose) initiative at Hinkley Point Power Station

International Nuclear Information System (INIS)

Weston, J.

1995-01-01

This paper does not offer a universal solution to reducing doses nor does it claim to introduce radically new ideas. It is a summarised account of the successes achieved in reducing the collective dose at a 30 year old power station. The key areas identified are the rewards of teamwork, the need to challenge established practices and the benefit of a dosimetry database. (author)

Reduced Language Connectivity in Pediatric Epilepsy

Science.gov (United States)

Leigh N., Sepeta; Louise J., Croft; Lauren A., Zimmaro; Elizabeth S., Duke; Virginia K., Terwilliger; Benjamin E., Yerys; Xiaozhen., You; Chandan J., Vaidya; William D., Gaillard; Madison M., Berl

2014-01-01

Objective Functional connectivity (FC) among language regions is decreased in adults with epilepsy compared to controls, but less is known about FC in children with epilepsy. We sought to determine if language FC is reduced in pediatric epilepsy, and examined clinical factors that associate with language FC in this population. Methods We assessed FC during an age-adjusted language task in children with left-hemisphere focal epilepsy (n=19) compared to controls (n=19). Time series data were extracted for three left ROIs and their right homologues: inferior frontal gyrus (IFG), middle frontal gyrus (MFG), and Wernicke's area (WA) using SPM8. Associations between FC and factors such as cognitive performance, language dominance, and epilepsy duration were assessed. Results Children with epilepsy showed decreased interhemispheric connectivity compared to controls, particularly between core left language regions (IFG, WA) and their right hemisphere homologues, as well as decreased intrahemispheric right frontal FC. Increased intrahemispheric FC between left IFG and left WA was a positive predictor of language skills overall, and naming ability in particular. FC of language areas was not affected by language dominance, as the effects remained when only examining study participants with left language dominance. Overall FC did not differ according to duration of epilepsy or age of onset. Significance FC during a language task is reduced in children, similar to findings in adults. In specific, children with left focal epilepsy demonstrated decreased interhemispheric FC in temporal and frontal language connections and decreased intrahemispheric right frontal FC. These differences were present near the onset of epilepsy. Greater FC between left language centers is related to better language ability. Our results highlight that connectivity of language areas has a developmental pattern and is related to cognitive ability. PMID:25516399

The impact of antecedent fire area on burned area in southern California coastal ecosystems

Science.gov (United States)

Price, Owen F.; Bradstock, Ross A.; Keeley, Jon E.; Syphard, Alexandra D.

2012-01-01

Frequent wildfire disasters in southern California highlight the need for risk reduction strategies for the region, of which fuel reduction via prescribed burning is one option. However, there is no consensus about the effectiveness of prescribed fire in reducing the area of wildfire. Here, we use 29 years of historical fire mapping to quantify the relationship between annual wildfire area and antecedent fire area in predominantly shrub and grassland fuels in seven southern California counties, controlling for annual variation in weather patterns. This method has been used elsewhere to measure leverage: the reduction in wildfire area resulting from one unit of prescribed fire treatment. We found little evidence for a leverage effect (leverage = zero). Specifically our results showed no evidence that wildfire area was negatively influenced by previous fires, and only weak relationships with weather variables rainfall and Santa Ana wind occurrences, which were variables included to control for inter-annual variation. We conclude that this is because only 2% of the vegetation burns each year and so wildfires rarely encounter burned patches and chaparral shrublands can carry a fire within 1 or 2 years after previous fire. Prescribed burning is unlikely to have much influence on fire regimes in this area, though targeted treatment at the urban interface may be effective at providing defensible space for protecting assets. These results fit an emerging global model of fire leverage which position California at the bottom end of a continuum, with tropical savannas at the top (leverage = 1: direct replacement of wildfire by prescribed fire) and Australian eucalypt forests in the middle (leverage ∼ 0.25).

Wildlife laws monitoring as an adaptive management tool in protected area management in Ghana: a case of Kakum Conservation Area.

Science.gov (United States)

Wiafe, Edward Debrah

2016-01-01

The wildlife laws of Ghana alienated the rural communities from forests and material well-being depended upon for their livelihood and this manifests itself in the progressive conflict between the park patrol staff and poachers from the fringes of the protected areas. The main aim of this study was to determine the impact of quantification of patrol efforts on indicators of illegal hunting activities that occur in rainforest protected areas, as a result of monitoring patrol operations and modifying the original plan. The specific objectives were to determine the optimal patrol efforts necessary to reduce illegal wildlife use to minimal; and the influence of the rainfall and seasonal activities on illegal wildlife use. The results indicated that as the patrol efforts increased the encounter with illegal wildlife use also increased until a certain point that the encounter rates started decreasing. Neither rainfall nor seasonal activities influenced the illegal activities and the patrol efforts. The protection staff of rainforest protected areas would work effectively to bring down illegal wildlife off-take to the barest minimum if monitored, quantified and provide feed-back. Illegal wildlife off-take can also be reduced by the protection staff if the original plans are made flexible to be adjusted. Recommendations for further studies have been made.

Preservation of wilderness areas in Europe

Directory of Open Access Journals (Sweden)

Zoltán Kun

2013-06-01

Full Text Available A unique momentum has been created over the past few years for strengthening the protection of wilderness in Europe. Policy makers started to pay attention to the importance of truly untouched and non-managed areas and the European Parliament adopted a special report on wilderness in February 2009. The report was followed by the EC Presidency Conference in Prague, May 2009, on Wilderness Areas. The most important outcome of this event was the approval of the ‘Agenda for Wilderness’, which eventually led to the inclusion of wilderness in the new EU Biodiversity Strategy. This paper argues that these political successes have yet to be put into practice. Threats to wilderness areas are still increasing and there have been no improvements in the management of these areas. There are emerging threats, especially from tree felling and mining, which is driven by increase in commodity prices. In order to save the last pieces of wilderness in Europe and utilize the current opportunities to restore wilderness areas, science and field conservation must develop a common Wilderness Research Agenda for Europe. The main questions are: (i What are the ecosystem services and benefits that humans obtain for wilderness areas? (ii What is the potential contribution of such wilderness areas for reducing biodiversity loss, halt species extinctions and support biodiversity restoration in Europe? (iii What is the social perception of wilderness in different countries and across different sectors of society? (iv What should be considered wilderness in a densely populated area such as Europe?

Reducing stress and fuel consumption providing road information

Directory of Open Access Journals (Sweden)

Víctor CORCOBA MAGAÑA

2014-12-01

Full Text Available In this paper, we propose a solution to reduce the stress level of the driver, minimize fuel consumption and improve safety. The system analyzes the driving style and the driver’s workload during the trip while driving. If it discovers an area where the stress increases and the driving style is not appropriate from the point of view of energy efficiency and safety for a particular driver, the location of this area is saved in a shared database. On the other hand, the implemented solution warns a particular user when approaching a region where the driving is difficult (high fuel consumption and stress using the shared database based on previous recorded knowledge of similar drivers in that area. In this case, the proposal provides an optimal deceleration profile if the vehicle speed is not adequate. Therefore, he or she may adjust the vehicle speed with both a positive impact on the driver workload and fuel consumption. The Data Envelopment Analysis algorithm is used to estimate the efficiency of driving and the driver’s workload in in each area. We employ this method because there is no preconceived form on the data in order to calculate the efficiency and stress level. A validation experiment has been conducted using both a driving simulator and a real environment with 12 participants who made 168 driving tests. The system reduced the slowdowns (38%, heart rate (4.70%, and fuel consumption (12.41% in the real environment. The proposed solution is implemented on Android mobile devices and does not require the installation of infrastructure on the road. It can be installed on any model of vehicle.

Pharmacodynamic Comparison of Rocuronium Bromide between Patients from the Plateau Area and from the Plain Area.

Science.gov (United States)

Xie, Min; Huang, Jianxin; Li, Peng; Ou, Zhiyan; Hou, Jing

2016-06-23

We aimed to conduct a pharmacodynamic comparison of rocuronium bromide between patients from the plateau area and from the plain area. A total of 104 patients who received laparoscopic cholecystectomy in Sichuan Provincial People's Hospital and Aba Autonomous Prefecture People's Hospital from October 2015 to December 2015 were included in this study. Among them, 46 patients were from the plateau area and 58 were from the plain area. Both groups received total intravenous anesthesia (TIVA) with a dose of 0.6mg/kg rocuronium bromide during induction. In the meantime, neuromuscular block was monitored using a train-of-four (TOF) stimulation mode. The onset time (time to achieve the lowest TOF value after the injection of rocuronium bromide), duration of maximal neuromuscular block (duration of lowest T1 value), time to 25% recovery, time to 75% recovery, recovery index (time from 25% recovery to 75% recovery), time to extubation, length of stay in Post Anesthesia Care Unit (PACU) and muscle strength upon PACU discharge were all recorded. The onset time, time to 25% recovery, time to 75% recovery and time to extubation were all significantly prolonged in patients from the plateau area after receiving one single dose of rocuronium bromide (P0.05). Compared to patients from the plain area, patients from the plateau area showed prolonged onset time of rocuronium bromide, reduced metabolic capabilities and longer duration of muscular relaxation. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.

Reducing consumption of electric current and energy carriers. [USSR

Energy Technology Data Exchange (ETDEWEB)

Ruppo, A.S.; Gruzdev, Yu.M.

1985-01-01

Evaluates the energy conservation program developed by the Giproshakht research institute is evaluated. The program was used in the Afanas'evo hydraulic mine in the Tulaugol association (with annual coal output of 2.1 Mt). Energy conservation program consisted of 2 groups of tasks: reducing energy consumption of the mine, and reducing energy consumption during the maximum demand hours in the morning and evening. The following methods were used: reducing idle running of chain and belt conveyors, separate draining of mine water free of dust and rock particles (reducing range of water cleaning), use of automatic control systems for mine blowers, automatic control of the system for coal drying, more efficient use of coal and materials transport in the mine. Energy demand of the mine during peak demand hours was reduced by adjusting fluctuations of energy consumption of the mine to fluctuations of energy demand in the power system of the area, e.g. by reducing mine draining in the morning and evening and operating at full capacity during the time of reduced energy demand. Using the energy conservation measures economized 4,324,300 kWh electric energy annually.

Developmental estrogen exposures and disruptions to maternal behavior and brain: Effects of ethinyl estradiol, a common positive control.

Science.gov (United States)

Catanese, Mary C; Vandenberg, Laura N

2017-11-07

Due of its structural similarity to the endogenous estrogen 17β-estradiol (E2), the synthetic estrogen 17α-ethinyl estradiol (EE2) is widely used to study the effects of estrogenic substances on sensitive organs at multiple stages of development. Here, we investigated the effects of EE2 on maternal behavior and the maternal brain in females exposed during gestation and the perinatal period. We assessed several components of maternal behavior including nesting behavior and pup retrieval; characterized the expression of estrogen receptor (ER)α in the medial preoptic area (MPOA), a brain region critical for the display of maternal behavior; and measured expression of tyrosine hydroxylase, a marker for dopaminergic cells, in the ventral tegmental area (VTA), a brain region important in maternal motivation. We found that developmental exposure to EE2 induces subtle effects on several aspects of maternal behavior including time building the nest and time spent engaged in self-care. Developmental exposure to EE2 also altered ERα expression in the central MPOA during both early and late lactation and led to significantly reduced tyrosine hydroxylase immunoreactivity in the VTA. Our results demonstrate both dose- and postpartum stage-related effects of developmental exposure to EE2 on behavior and brain that manifest later in adulthood, during the maternal period. These findings provide further evidence for effects of exposure to exogenous estrogenic compounds during the critical periods of fetal and perinatal development. Copyright © 2017 Elsevier Inc. All rights reserved.

Chronic nicotine-induced changes in gene expression of delta and kappa-opioid receptors and their endogenous ligands in the mesocorticolimbic system of the rat.

Science.gov (United States)

Ugur, Muzeyyen; Kaya, Egemen; Gozen, Oguz; Koylu, Ersin O; Kanit, Lutfiye; Keser, Aysegul; Balkan, Burcu

2017-09-01

Delta and kappa opioid receptors (DOR and KOR, respectively) and their endogenous ligands, proenkephalin (PENK) and prodynorphin (PDYN)-derived opioid peptides are proposed as important mediators of nicotine reward. This study investigated the regulatory effect of chronic nicotine treatment on the gene expression of DOR, KOR, PENK and PDYN in the mesocorticolimbic system. Three groups of rats were injected subcutaneously with nicotine at doses of 0.2, 0.4, or 0.6 mg/kg/day for 6 days. Rats were decapitated 1 hr after the last dose on day six, as this timing coincides with increased dopamine release in the mesocorticolimbic system. mRNA levels in the ventral tegmental area (VTA), lateral hypothalamic area (LHA), amygdala (AMG), dorsal striatum (DST), nucleus accumbens, and medial prefrontal cortex were measured by quantitative real-time PCR. Our results showed that nicotine upregulated DOR mRNA in the VTA at all of the doses employed, in the AMG at the 0.4 and 0.6 mg/kg doses, and in the DST at the 0.4 mg/kg dose. Conversely, PDYN mRNA was reduced in the LHA with 0.6 mg/kg nicotine and in the AMG with 0.4 mg/kg nicotine. KOR mRNA was also decreased in the DST with 0.6 mg/kg nicotine. Nicotine did not regulate PENK mRNA in any brain region studied. © 2017 Wiley Periodicals, Inc.

Concepts for reducing nuclear utility inventory carrying costs

International Nuclear Information System (INIS)

Graybill, R.E.; DiCola, F.E.; Solanas, C.H.

1985-01-01

Nuclear utilities are under pressure to reduce their operating and maintenance expenses such that the total cost of generating electricity through nuclear power remains an economically attractive option. One area in which expenses may be reduced is total inventory carrying cost. The total inventory carrying cost consists of financing an inventory, managing the inventory, assuring quality, engineering of acceptable parts specifications, and procuring initial and replenishment stock. Concepts and methodology must be developed to reduce the remaining expenses of a utility's total inventory carrying cost. Currently, two concepts exist: pooled inventory management system (PIMS), originally established by General Electric Company and a group of boiling water reactor owners, and Nuclear Parts Associates' (NUPA) shared inventory management program (SIMP). Both concepts share or pool parts and components among utilities. The SIMP program objectives and technical activities are summarized

Modulation of tyrosine hydroxylase gene expression in the central nervous system visualized by in situ hybridization

International Nuclear Information System (INIS)

Berod, A.; Biguet, N.F.; Dumas, S.; Bloch, B.; Mallet, J.

1987-01-01

cDNA probe was used for in situ hybridization studies on histological sections through the locus coeruleus, substantia nigra, and the ventral tegmental area of the rat brain. Experimental conditions were established that yielded no background and no signal when pBR322 was used as control probe. Using the tyrosine hydroxylase probe, the authors ascertained the specificity of the labeling over catecholaminergic cells by denervation experiments and comparison of the hybridization pattern with that of immunoreactivity. The use of 35 S-labeled probe enabled the hybridization signal to be resolved at the cellular level. A single injection of reserpine into the rat led to an increase of the intensity of the autoradiographic signal over the locus coeruleus area, confirming an RNA gel blot analysis. The potential of in situ hybridization to analyze patterns of modulation of gene activity as a result of nervous activity is discussed

Romantická láska z pohľadu sociálnej neurovedy (Romantic love from a social neuroscience perspective

Directory of Open Access Journals (Sweden)

Marián Špajdel

2013-12-01

Full Text Available Gregor A., Špajdel M.: Romantic love from a social neuroscience perspective In our work we describe romantic love in terms of cerebral activity and define its specific anatomic correlates. We also offer a sum of current knowledge coming out from the previous research in social neuroscience and provide a picture of how is brain activity connected with psychological processes. Analysis of gathered data shows Chat romantic love activates not only subcortical regions, which mediates a variety of emotions involved in motivation and reward-seeking, but also activates higher cerebral areas involved in social cognition, attention, memory, mental association, and self-representation. Romantic love has its strongest base in ventral tegmental area and caudate nucleus, which are the primar regions of infatuation respectively. Other regions such as cingular cortex, posterior hippocamus, and hypothalamus deal with attachment bond, sexual desire, and inclusion of other in the Self.

Pramipexole but not imipramine or fluoxetine reverses the "depressive-like" behaviour in a rat model of preclinical stages of Parkinson's disease.

Science.gov (United States)

Berghauzen-Maciejewska, Klemencja; Kuter, Katarzyna; Kolasiewicz, Wacław; Głowacka, Urszula; Dziubina, Anna; Ossowska, Krystyna; Wardas, Jadwiga

2014-09-01

Depression is a frequent comorbid disorder in Parkinson's disease and may antedate its motor symptoms. However, mechanisms underlying Parkinson's disease-associated depression are unknown and its current medication is insufficient. The aim of the present study was to compare antidepressant-like effects of imipramine, fluoxetine and pramipexole in a model of preclinical stages of Parkinson's disease in rats. 6-Hydroxydopamine was bilaterally injected into the ventrolateral region of the caudate-putamen in rats. This treatment induced moderate decreases in the levels of dopamine and its metabolites in the caudate-putamen, nucleus accumbens and frontal cortex and reduced the density of tyrosine hydroxylase-immunoreactive neurons in the substantia nigra pars compacta and ventral tegmental area. The lesion increased immobility measured in the forced swimming test without influencing locomotor activity. Chronic (13 days) administration of pramipexole (1mg/kg sc/twice a day) reversed prolongation of the immobility time in lesioned animals but did not stimulate their locomotion. Chronic pramipexole activated dopaminergic transmission in the brain structures which might contribute to its effectiveness in the forced swimming test. In contrast, the 13-day administration of imipramine (10mg/kg ip/day) and fluoxetine (10mg/kg ip/day) did not shorten the immobility time in lesioned rats but reduced their locomotion. The present study indicates that already a moderate lesion of dopaminergic neurons induces "depressive-like" behaviour in animals which is reversed by chronic administration of the antiparkinsonian drug, pramipexole. Copyright © 2014 Elsevier B.V. All rights reserved.

Integration of reward signalling and appetite regulating peptide systems in the control of food-cue responses.

Science.gov (United States)

Reichelt, A C; Westbrook, R F; Morris, M J

2015-11-01

Understanding the neurobiological substrates that encode learning about food-associated cues and how those signals are modulated is of great clinical importance especially in light of the worldwide obesity problem. Inappropriate or maladaptive responses to food-associated cues can promote over-consumption, leading to excessive energy intake and weight gain. Chronic exposure to foods rich in fat and sugar alters the reinforcing value of foods and weakens inhibitory neural control, triggering learned, but maladaptive, associations between environmental cues and food rewards. Thus, responses to food-associated cues can promote cravings and food-seeking by activating mesocorticolimbic dopamine neurocircuitry, and exert physiological effects including salivation. These responses may be analogous to the cravings experienced by abstaining drug addicts that can trigger relapse into drug self-administration. Preventing cue-triggered eating may therefore reduce the over-consumption seen in obesity and binge-eating disorder. In this review we discuss recent research examining how cues associated with palatable foods can promote reward-based feeding behaviours and the potential involvement of appetite-regulating peptides including leptin, ghrelin, orexin and melanin concentrating hormone. These peptide signals interface with mesolimbic dopaminergic regions including the ventral tegmental area to modulate reactivity to cues associated with palatable foods. Thus, a novel target for anti-obesity therapeutics is to reduce non-homeostatic, reward driven eating behaviour, which can be triggered by environmental cues associated with highly palatable, fat and sugar rich foods. © 2015 The British Pharmacological Society.

SCIENCE AND TECHNOLOGY ACTIVITIES FOR CHROMIUM IN THE 100 AREAS

Energy Technology Data Exchange (ETDEWEB)

PETERSEN SW

2009-07-02

{sm_bullet} Primary Objective: Protect the Columbia River - Focus is control and treatment of contamination at or near the shoreline, which is influenced by bank storage {sm_bullet} Secondary Objective: Reduce hexavalent chromium to <48 parts per billion (ppb) in aquifer (drinking water standard) - Large plumes with isolated areas of high chromium concentrations (> 40,000 ppb), - Unknown source location(s); probably originating in reactor operation areas

Natural disturbance reduces disease risk in endangered rainforest frog populations.

Science.gov (United States)

Roznik, Elizabeth A; Sapsford, Sarah J; Pike, David A; Schwarzkopf, Lin; Alford, Ross A

2015-08-21

Natural disturbances can drive disease dynamics in animal populations by altering the microclimates experienced by hosts and their pathogens. Many pathogens are highly sensitive to temperature and moisture, and therefore small changes in habitat structure can alter the microclimate in ways that increase or decrease infection prevalence and intensity in host populations. Here we show that a reduction of rainforest canopy cover caused by a severe tropical cyclone decreased the risk of endangered rainforest frogs (Litoria rheocola) becoming infected by a fungal pathogen (Batrachochytrium dendrobatidis). Reductions in canopy cover increased the temperatures and rates of evaporative water loss in frog microhabitats, which reduced B. dendrobatidis infection risk in frogs by an average of 11-28% in cyclone-damaged areas, relative to unaffected areas. Natural disturbances to the rainforest canopy can therefore provide an immediate benefit to frogs by altering the microclimate in ways that reduce infection risk. This could increase host survival and reduce the probability of epidemic disease outbreaks. For amphibian populations under immediate threat from this pathogen, targeted manipulation of canopy cover could increase the availability of warmer, drier microclimates and therefore tip the balance from host extinction to coexistence.

Reducing violence in poor urban areas of Honduras by building community resilience through community-based interventions.

Science.gov (United States)

Hansen-Nord, Nete Sloth; Kjaerulf, Finn; Almendarez, Juan; Rodas, Victor Morales; Castro, Julio

2016-11-01

To examine the impact of a 3 year community-based violence prevention intervention on risk of violence and social capital in two poor urban communities in Honduras in 2011-2014. A quasi-experimental design pre and post implementation of the intervention was conducted based on data from two randomly selected samples using the same structured questionnaire in 2011 and in 2014. Community members had a 42 % lower risk of violence in 2014 compared to 2011. There was a positive relation between participation in the intervention and structural social capital, and participants had more than twice the likelihood of engaging in citizenship activities compared to the general population. The intervention contributed to decreasing violence and increasing community resilience in two urban areas in Honduras. Citizenship activities and active community participation in the violence prevention agenda rather than social trust and cohesion characteristics was affected by the intervention. This research introduces important lessons learned to future researchers aiming to retrieve very sensitive data in a similarly violent setting, and provides strong research opportunities within areas, which to this date remain undiscovered.

Fault Identification Algorithm Based on Zone-Division Wide Area Protection System

OpenAIRE

Xiaojun Liu; Youcheng Wang; Hub Hu

2014-01-01

As the power grid becomes more magnified and complicated, wide-area protection system in the practical engineering application is more and more restricted by the communication level. Based on the concept of limitedness of wide-area protection system, the grid with complex structure is divided orderly in this paper, and fault identification and protection action are executed in each divided zone to reduce the pressure of the communication system. In protection zone, a new wide-area...

Report card on low level ozone in urban areas

Energy Technology Data Exchange (ETDEWEB)

Onischak, M.

1994-12-31

It has been four years since the Clean Air Act was amended in November of 1990. Much work has been done in this time, and the country is beginning to see real air quality benefits. Although these changes have not completely licked the urban ozone problem yet, they have made a lot of progress. All of the urban areas which have been required to reduce their ozone levels have done a good job of lowering their emissions. While the urban areas have not all been able to meet every federal deadline, the areas have all been able to achieve the control milestones before the mandatory Clean Air Act sanctions have taken effect. Some areas are even ready to declare their ozone problems solved.

Report card on low level ozone in urban areas

International Nuclear Information System (INIS)

Onischak, M.

1994-01-01

It has been four years since the Clean Air Act was amended in November of 1990. Much work has been done in this time, and the country is beginning to see real air quality benefits. Although these changes have not completely licked the urban ozone problem yet, they have made a lot of progress. All of the urban areas which have been required to reduce their ozone levels have done a good job of lowering their emissions. While the urban areas have not all been able to meet every federal deadline, the areas have all been able to achieve the control milestones before the mandatory Clean Air Act sanctions have taken effect. Some areas are even ready to declare their ozone problems solved

Reducing occupational radiation exposures at LWRs

International Nuclear Information System (INIS)

Lattanzi, D.; Neri, C.; Papa, C.; Paribelli, S.

1980-01-01

The occupational radiation doses received by nuclear power plant personnel during a period of several years of operation are briefly reviewed. Comparisons are made between the data for BWRs and PWRs in order to identify the more ''critical'' reactor type, from a radiological poin; of view. Attention is also devoted to GCRs. Furthermore the areas which contribute most to personnel doses are considered and briefly reviewed. The main steps to be taken in order to reduce occupational radiation exposures at LWRs are discussed. (H.K.)

Flow area optimization in point to area or area to point flows

International Nuclear Information System (INIS)

Ghodoossi, Lotfollah; Egrican, Niluefer

2003-01-01

This paper deals with the constructal theory of generation of shape and structure in flow systems connecting one point to a finite size area. The flow direction may be either from the point to the area or the area to the point. The formulation of the problem remains the same if the flow direction is reversed. Two models are used in optimization of the point to area or area to point flow problem: cost minimization and revenue maximization. The cost minimization model enables one to predict the shape of the optimized flow areas, but the geometric sizes of the flow areas are not predictable. That is, as an example, if the area of flow is a rectangle with a fixed area size, optimization of the point to area or area to point flow problem by using the cost minimization model will only predict the height/length ratio of the rectangle not the height and length itself. By using the revenue maximization model in optimization of the flow problems, all optimized geometric aspects of the interested flow areas will be derived as well. The aim of this paper is to optimize the point to area or area to point flow problems in various elemental flow area shapes and various structures of the flow system (various combinations of elemental flow areas) by using the revenue maximization model. The elemental flow area shapes used in this paper are either rectangular or triangular. The forms of the flow area structure, made up of an assembly of optimized elemental flow areas to obtain bigger flow areas, are rectangle-in-rectangle, rectangle-in-triangle, triangle-in-triangle and triangle-in-rectangle. The global maximum revenue, revenue collected per unit flow area and the shape and sizes of each flow area structure have been derived in optimized conditions. The results for each flow area structure have been compared with the results of the other structures to determine the structure that provides better performance. The conclusion is that the rectangle-in-triangle flow area structure

Gut peptide GLP-1 and its analogue, Exendin-4, decrease alcohol intake and reward.

Directory of Open Access Journals (Sweden)

Rozita H Shirazi

Full Text Available Glucagon-like-peptide-1 (GLP-1 is a gut- and neuro-peptide with an important role in the regulation of food intake and glucose metabolism. Interestingly, GLP-1 receptors (GLP-1R are expressed in key mesolimbic reward areas (including the ventral tegmental area, VTA, innervated by hindbrain GLP-1 neurons. Recently GLP-1 has emerged as a potential regulator of food reward behavior, an effect driven by the mesolimbic GLP-1Rs. Its role in other reward behaviors remains largely unexplored. Since a considerable overlap has been suggested for circuitry controlling reward behavior derived from food and alcohol we hypothesized that GLP-1 and GLP-1Rs could regulate alcohol intake and alcohol reward. We sought to determine whether GLP-1 or its clinically safe stable analogue, Exendin-4, reduce alcohol intake and reward. To determine the potential role of the endogenous GLP-1 in alcohol intake we evaluated whether GLP-1R antagonist, Exendin 9-39, can increase alcohol intake. Furthermore, we set out to evaluate whether VTA GLP-1R activation is sufficient to reduce alcohol intake. Male Wistar rats injected peripherally with GLP-1 or Exendin-4 reduced their alcohol intake in an intermittent access two bottle free choice drinking model. Importantly, a contribution of endogenously released GLP-1 is highlighted by our observation that blockade of GLP-1 receptors alone resulted in an increased alcohol intake. Furthermore, GLP-1 injection reduced alcohol reward in the alcohol conditioned place preference test in mice. To evaluate the neuroanatomical substrate linking GLP-1 with alcohol intake/reward, we selectively microinjected GLP-1 or Exendin 4 into the VTA. This direct stimulation of the VTA GLP-1 receptors potently reduced alcohol intake. Our findings implicate GLP-1R signaling as a novel modulator of alcohol intake and reward. We show for the first time that VTA GLP-1R stimulation leads to reduced alcohol intake. Considering that GLP-1 analogues are already

Automation of Commanding at NASA: Reducing Human Error in Space Flight

Science.gov (United States)

Dorn, Sarah J.

2010-01-01

Automation has been implemented in many different industries to improve efficiency and reduce human error. Reducing or eliminating the human interaction in tasks has been proven to increase productivity in manufacturing and lessen the risk of mistakes by humans in the airline industry. Human space flight requires the flight controllers to monitor multiple systems and react quickly when failures occur so NASA is interested in implementing techniques that can assist in these tasks. Using automation to control some of these responsibilities could reduce the number of errors the flight controllers encounter due to standard human error characteristics. This paper will investigate the possibility of reducing human error in the critical area of manned space flight at NASA.

Effect of Urban Green Spaces and Flooded Area Type on Flooding Probability

Directory of Open Access Journals (Sweden)

Hyomin Kim

2016-01-01

Full Text Available Countermeasures to urban flooding should consider long-term perspectives, because climate change impacts are unpredictable and complex. Urban green spaces have emerged as a potential option to reduce urban flood risks, and their effectiveness has been highlighted in notable urban water management studies. In this study, flooded areas in Seoul, Korea, were divided into four flooded area types by cluster analysis based on topographic and physical characteristics and verified using discriminant analysis. After division by flooded area type, logistic regression analysis was performed to determine how the flooding probability changes with variations in green space area. Type 1 included regions where flooding occurred in a drainage basin that had a flood risk management infrastructure (FRMI. In Type 2, the slope was steep; the TWI (Topographic Wetness Index was relatively low; and soil drainage was favorable. Type 3 represented the gentlest sloping areas, and these were associated with the highest TWI values. In addition, these areas had the worst soil drainage. Type 4 had moderate slopes, imperfect soil drainage and lower than average TWI values. We found that green spaces exerted a considerable influence on urban flooding probabilities in Seoul, and flooding probabilities could be reduced by over 50% depending on the green space area and the locations where green spaces were introduced. Increasing the area of green spaces was the most effective method of decreasing flooding probability in Type 3 areas. In Type 2 areas, the maximum hourly precipitation affected the flooding probability significantly, and the flooding probability in these areas was high despite the extensive green space area. These findings can contribute towards establishing guidelines for urban spatial planning to respond to urban flooding.

GABAergic actions on cholinergic laterodorsal tegmental neurons

DEFF Research Database (Denmark)

Kohlmeier, K A; Kristiansen, Uffe

2010-01-01

Cholinergic neurons of the pontine laterodorsal tegmentum (LDT) play a critical role in regulation of behavioral state. Therefore, elucidation of mechanisms that control their activity is vital for understanding of how switching between wakefulness, sleep and anesthetic states is effectuated....... In vivo studies suggest that GABAergic mechanisms within the pons play a critical role in behavioral state switching. However, the postsynaptic, electrophysiological actions of GABA on LDT neurons, as well as the identity of GABA receptors present in the LDT mediating these actions is virtually unexplored...... neurons. Post-synaptic location of GABA(A) receptors was demonstrated by persistence of muscimol-induced inward currents in TTX and low Ca(2+) solutions. THIP, a selective GABA(A) receptor agonist with a preference for d-subunit containing GABA(A) receptors, induced inward currents, suggesting...

Bi-directional effect of increasing doses of baclofen on reinforcement learning

Directory of Open Access Journals (Sweden)

Jean eTerrier

2011-07-01

Full Text Available In rodents as well as in humans, efficient reinforcement learning depends on dopamine (DA released from ventral tegmental area (VTA neurons. It has been shown that in brain slices of mice, GABAB-receptor agonists at low concentrations increase the firing frequency of VTA-DA neurons, while high concentrations reduce the firing frequency. It remains however elusive whether baclofen can modulate reinforcement learning. Here, in a double blind study in 34 healthy human volunteers, we tested the effects of a low and a high concentration of oral baclofen in a gambling task associated with monetary reward. A low (20 mg dose of baclofen increased the efficiency of reward-associated learning but had no effect on the avoidance of monetary loss. A high (50 mg dose of baclofen on the other hand did not affect the learning curve. At the end of the task, subjects who received 20 mg baclofen p.o. were more accurate in choosing the symbol linked to the highest probability of earning money compared to the control group (89.55±1.39% vs 81.07±1.55%, p=0.002. Our results support a model where baclofen, at low concentrations, causes a disinhibition of DA neurons, increases DA levels and thus facilitates reinforcement learning.

Glutamatergic transmission in drug reward: implications for drug addiction.

Science.gov (United States)

D'Souza, Manoranjan S

2015-01-01

Individuals addicted to drugs of abuse such as alcohol, nicotine, cocaine, and heroin are a significant burden on healthcare systems all over the world. The positive reinforcing (rewarding) effects of the above mentioned drugs play a major role in the initiation and maintenance of the drug-taking habit. Thus, understanding the neurochemical mechanisms underlying the reinforcing effects of drugs of abuse is critical to reducing the burden of drug addiction in society. Over the last two decades, there has been an increasing focus on the role of the excitatory neurotransmitter glutamate in drug addiction. In this review, pharmacological and genetic evidence supporting the role of glutamate in mediating the rewarding effects of the above described drugs of abuse will be discussed. Further, the review will discuss the role of glutamate transmission in two complex heterogeneous brain regions, namely the nucleus accumbens (NAcc) and the ventral tegmental area (VTA), which mediate the rewarding effects of drugs of abuse. In addition, several medications approved by the Food and Drug Administration that act by blocking glutamate transmission will be discussed in the context of drug reward. Finally, this review will discuss future studies needed to address currently unanswered gaps in knowledge, which will further elucidate the role of glutamate in the rewarding effects of drugs of abuse.

Synaptic potentiation onto habenula neurons in learned helplessness model of depression

Science.gov (United States)

Li, Bo; Piriz, Joaquin; Mirrione, Martine; Chung, ChiHye; Proulx, Christophe D.; Schulz, Daniela; Henn, Fritz; Malinow, Roberto

2010-01-01

The cellular basis of depressive disorders is poorly understood1. Recent studies in monkeys indicate that neurons in the lateral habenula (LHb), a nucleus that mediates communication between forebrain and midbrain structures, can increase their activity when an animal fails to receive an expected positive reward or receives a stimulus that predicts aversive conditions (i.e. disappointment or anticipation of a negative outcome)2, 3, 4. LHb neurons project to and modulate dopamine-rich regions such as the ventral-tegmental area (VTA)2, 5 that control reward-seeking behavior6 and participate in depressive disorders7. Here we show in two learned helplessness models of depression that excitatory synapses onto LHb neurons projecting to the VTA are potentiated. Synaptic potentiation correlates with an animal’s helplessness behavior and is due to an enhanced presynaptic release probability. Depleting transmitter release by repeated electrical stimulation of LHb afferents, using a protocol that can be effective on depressed patients8, 9, dramatically suppresses synaptic drive onto VTA-projecting LHb neurons in brain slices and can significantly reduce learned helplessness behavior in rats. Our results indicate that increased presynaptic action onto LHb neurons contributes to the rodent learned helplessness model of depression. PMID:21350486

Open areas and open access

International Nuclear Information System (INIS)

Thorndike, A.M.

1979-01-01

The main objective of the two open areas in the present ISABELLE design has been to provide flexibility with respect to the size and shape of experimental equipment that would eventually be installed there. No permanent building would be installed initially. One possibility would be to enclose each experiment in a temporary structure that would provide weatherproofing and shielding; another possibility would be to erect a permanent building at a later time, when experience has made the needs clearer than they are at present. The secondary objective of the design of open areas has been to keep initial costs as low as practicable. Another objective might be added, however, which we indicate by the term ''open access.'' This note will explore this idea and some design concepts based on it. In the ISABELLE 1977 summer workshop there was considerable discussion of the importance of techniques for inserting large pieces of experimental equipment quickly and removing them with equal ease and speed. Since enclosed halls have certain restrictions in this respect, open areas may be helpful in providing this feature. If the mechanical and electrical aspects could be handled quickly, one might even attempt to reduce the time spent on bureaucratic procedures in order to expedite the introduction of new experiments and new ideas in these areas

Effects of the increased radium content in soil on the soil fauna

International Nuclear Information System (INIS)

Krivolutskij, D.A.; Druk, A.Ya.; Semenova, L.M.; Semyashkina, T.M.; Mikhal'tsova, Z.A.

1978-01-01

The effect of elevated radioactive background due to the presence of natural radionuclide of radium-226 on soil animals has been studied. The areas being studied (1-2 hectares) had the elevated radioactivity ranging from 50 to 4000 μR/hour and were located on an over-flood-lands terrace with meadow vegetation in the mid-taiga subzone. Histological examination of tegmental epithelium and middle intestine (tissues in direct contact with radium-contaminated soil) was performed on Dendrobaena octaedra (Sav.) and Dendrodrillus rubidus (Sav.) collected from areas with 4000μR/hour radioactivity. A comparison of the results with data obtained earlier for surface animals inhabiting the same areas has corroborated that settled animals inhabiting contaminated areas for a long time suffer from retardation of development and disturbances in the functioning of body epithelium and of the intestine. The effect of radiation on soil animals can be observed in areas with far lower radioactivity (100-200μR/hour), probably due to their closer contact with radium-contaminated soil. The most convenient object for monitoring of the effects of elevated background radioactivity is the earthworm, which is irradiated not only from outside but also from the smallowed soil

Aliens in Antarctica: Assessing transfer of plant propagules by human visitors to reduce invasion risk

NARCIS (Netherlands)

Huiskes, A.H.L.; Gremmen, N.J.M.; Bergstrom, D.M.; Frenot, Y.; Hughes, K.A.; Imura, S.; Kiefer, K.; Lebouvier, M.; Lee, J.E.; Tsujimoto, M.; Ware, C.; Van de Vijver, B.; Chown, S.L.

2014-01-01

Despite considerable research on biological invasions, key areas remain poorly explored, especially ways to reduce unintentional propagule transfer. The Antarctic represents a microcosm of the situation, with the numbers of established non-native species growing. Information to help reduce potential

The economic benefits of vegetation in the upstream area of Ciliwung watershed

Science.gov (United States)

Saridewi, T. R.; Nazaruddin

2018-04-01

Ciliwung watershed has strategic values since its entire downstream area is located in the Special Administrative Region of Jakarta (DKI Jakarta), the capital of Indonesia. This causes forest and farmland areas are converted into open areas or built-up areas. The existence of these areas provides enormous environmental and economic benefits. Economic benefit values are very important to be considered in developing a policy development plan, but they have not been calculated yet. This study aims to determine the economic benefits provided by trees and other vegetation anddevelops a development policy that takes into account simultaneously ecological and economic aspects. The study is conducted in the upstream Ciliwung watershed, by using land cover patterns in 1989, 2000, 2010 and 2014, and employs GIS and CITY green analysis. The results show that conversion of forest and farmland areas reduces the ability of Ciliwung upstream watershed to store water. Therefore, its ability to reduce the flow of surface has been decreased. This creates a decrease in the cost savings of annual stormwater, from US 15,175,721 in 1989 to US 13,317,469 in 2014. The Environmental Services Payment Policy (PES) for upstream community groups managing the watershed has been considered as a fairly effective policy.

Methods for Engineering Sulfate Reducing Bacteria of the Genus Desulfovibrio

Energy Technology Data Exchange (ETDEWEB)

Chhabra, Swapnil R; Keller, Kimberly L.; Wall, Judy D.

2011-03-15

Sulfate reducing bacteria are physiologically important given their nearly ubiquitous presence and have important applications in the areas of bioremediation and bioenergy. This chapter provides details on the steps used for homologous-recombination mediated chromosomal manipulation of Desulfovibrio vulgaris Hildenborough, a well-studied sulfate reducer. More specifically, we focus on the implementation of a 'parts' based approach for suicide vector assembly, important aspects of anaerobic culturing, choices for antibiotic selection, electroporation-based DNA transformation, as well as tools for screening and verifying genetically modified constructs. These methods, which in principle may be extended to other sulfate-reducing bacteria, are applicable for functional genomics investigations, as well as metabolic engineering manipulations.

Analysis of justification for applying two gear sets within the universal gear reducers

OpenAIRE

Rackov Milan; Kuzmanović Siniša; Knežević Ivan; Čavić Maja; Penčić Marko

2017-01-01

In the area of universal gear reducers, standard does not prescribe relations between load capacity, gear ratios and axis heights. Therefore, larger load capacity of some gear reducers manufacturers has advantage for lower gear ratio and, vice versa, smaller load capacity of the gearbox achieves higher values of gear ratio. However, there are some manufacturers who produce gear reducers with smaller or larger load capacity for higher or lower gear ratio, within the same axis height. This pape...

Household methods to reduce 137Cs contents of mushrooms

International Nuclear Information System (INIS)

Kostiainen, E.

2005-01-01

High radiocaesium contents in different species of mushrooms have been observed in areas contaminated by radiocaesium deposition after the Chernobyl accident in 1986. There has been no significant reduction in the 137 Cs contents of mushrooms during the past ten years, besides via radioactive decay. The internal radiation dose received via mushrooms can be reduced by processing mushrooms before consumption. Various household methods were studied to find out their efficiency to reduce 137 Cs contents of mushrooms. The methods tested were the same as normally used in cooking. The tests were made for the species of edible mushrooms widely consumed. The retention factors for the treatments tested were in most cases 0.2-0.3. The efficiency of treatments in reducing the 137 Cs contents increased with larger water volumes and prolonged treatment times

The role of the lateral habenula in punishment.

Science.gov (United States)

Jean-Richard Dit Bressel, Philip; McNally, Gavan P

2014-01-01

The lateral habenula (LHb) is a small epithalamic structure that projects via the fasciculus retroflexus to the midbrain. The LHb is known to modulate midbrain dopamine (DA) neurons, including inhibition of ventral tegmental area (VTA) neurons via glutamatergic excitation of the GABAergic rostromedial tegmental nucleus (RMTg). A variety of lines of evidence show activity in LHb and the LHb-RMTg pathway is correlated with, and is sufficient to support, punishment learning. However, it is not immediately clear whether LHb is necessary for punishment. Here we used a within-subjects punishment task to assess the role of LHb in the acquisition and expression of punishment as well as in aversive choice. Rats that pressed two individually presented levers for pellet rewards rapidly suppressed responding to one lever if it also caused footshock deliveries (punished lever) but continued pressing a second lever that did not cause footshock (unpunished lever). Infusions of an AMPA receptor antagonist (NBQX) into LHb had no effect on the acquisition or expression of this punishment, or on aversive choice, but did increase locomotion. Infusion of the sodium channel blocker bupivacaine likewise had no effect on expression of punishment. However, infusion of the calcium channel blocker mibefradil did affect expression of punishment by significantly decreasing the latency with which rats responded on the punished lever and significantly increasing unpunished lever-pressing. Taken together, these findings indicate that the LHb plays a limited role in punishment, influencing only latency to respond. This role is linked to calcium channel permeability and not AMPA receptor or sodium channel permeability.

Nicotine aversion: Neurobiological mechanisms and relevance to tobacco dependence vulnerability

Science.gov (United States)

Fowler, Christie D.; Kenny, Paul J.

2013-01-01

Nicotine stimulates brain reward circuitries, most prominently the mesocorticolimbic dopamine system, and this action is considered critical in establishing and maintaining the tobacco smoking habit. Compounds that attenuate nicotine reward are considered promising therapeutic candidates for tobacco dependence, but many of these agents have other actions that limit their potential utility. Nicotine is also highly noxious, particularly at higher doses, and aversive reactions to nicotine after initial exposure can decrease the likelihood of developing a tobacco habit in many first time smokers. Nevertheless, relatively little is known about the mechanisms of nicotine aversion. The purpose of this review is to present recent new insights into the neurobiological mechanisms that regulate avoidance of nicotine. First, the role of the mesocorticolimbic system, so often associated with nicotine reward, in regulating nicotine aversion is highlighted. Second, genetic variation that modifies noxious responses to nicotine and thereby influences vulnerability to tobacco dependence, in particular variation in the CHRNA5-CHRNA3-CHRNB4 nicotinic acetylcholine receptor (nAChR) subunit gene cluster, will be discussed. Third, the role of the habenular complex in nicotine aversion, primarily medial habenular projections to the interpeduncular nucleus (IPN) but also lateral habenular projections to rostromedial tegmental nucleus (RMTg) and ventral tegmental area (VTA) are reviewed. Forth, brain circuits that are enriched in nAChRs, but whose role in nicotine avoidance has not yet been assessed, will be proposed. Finally, the feasibility of developing novel therapeutic agents for tobacco dependence that act not by blocking nicotine reward but by enhancing nicotine avoidance will be considered. PMID:24055497

Electrophysiological and morphological properties of neurons in the prepositus hypoglossi nucleus that express both ChAT and VGAT in a double-transgenic rat model.

Science.gov (United States)

Saito, Yasuhiko; Zhang, Yue; Yanagawa, Yuchio

2015-04-01

Although it has been proposed that neurons that contain both acetylcholine (ACh) and γ-aminobutyric acid (GABA) are present in the prepositus hypoglossi nucleus (PHN), these neurons have not been characterized because of the difficulty in identifying them. In the present study, PHN neurons that express both choline acetyltransferase and the vesicular GABA transporter (VGAT) were identified using double-transgenic rats, in which the cholinergic and inhibitory neurons express the fluorescent proteins tdTomato and Venus, respectively. To characterize the neurons that express both tdTomato and Venus (D+ neurons), the afterhyperpolarization (AHP) profiles and firing patterns of these neurons were investigated via whole-cell recordings of brainstem slice preparations. Regarding the three AHP profiles and four firing patterns that the D+ neurons exhibited, an AHP with an afterdepolarization and a firing pattern that exhibited a delay in the generation of the first spike were the preferential properties of these neurons. In the three morphological types classified, the multipolar type that exhibited radiating dendrites was predominant among the D+ neurons. Immunocytochemical analysis revealed that the VGAT-immunopositive axonal boutons that expressed tdTomato were primarily located in the dorsal cap of inferior olive (IO) and the PHN. Although the PHN receives cholinergic inputs from the pedunculopontine tegmental nucleus and laterodorsal tegmental nucleus, D+ neurons were absent from these brain areas. Together, these results suggest that PHN neurons that co-express ACh and GABA exhibit specific electrophysiological and morphological properties, and innervate the dorsal cap of the IO and the PHN. © 2015 Federation of European Neuroscience Societies and John Wiley & Sons Ltd.

77 FR 45290 - Proposed Modification of Class B Airspace Area; Philadelphia, PA

Science.gov (United States)

2012-07-31

... environment for all users of the ATC system. VFR aircraft wishing to transit the portion of Alert Area A-220... aircraft to operate at higher altitudes. PHL Airport Traffic Control Tower (ATCT) has made a commitment to... enroute airspace areas to reduce aircraft delays and improve system capacity. Costs of the Proposed Action...

Breast Cancer Detection with Reduced Feature Set

Directory of Open Access Journals (Sweden)

Ahmet Mert

2015-01-01

Full Text Available This paper explores feature reduction properties of independent component analysis (ICA on breast cancer decision support system. Wisconsin diagnostic breast cancer (WDBC dataset is reduced to one-dimensional feature vector computing an independent component (IC. The original data with 30 features and reduced one feature (IC are used to evaluate diagnostic accuracy of the classifiers such as k-nearest neighbor (k-NN, artificial neural network (ANN, radial basis function neural network (RBFNN, and support vector machine (SVM. The comparison of the proposed classification using the IC with original feature set is also tested on different validation (5/10-fold cross-validations and partitioning (20%–40% methods. These classifiers are evaluated how to effectively categorize tumors as benign and malignant in terms of specificity, sensitivity, accuracy, F-score, Youden’s index, discriminant power, and the receiver operating characteristic (ROC curve with its criterion values including area under curve (AUC and 95% confidential interval (CI. This represents an improvement in diagnostic decision support system, while reducing computational complexity.

Near-infrared deep brain stimulation via upconversion nanoparticle–mediated optogenetics

Science.gov (United States)

Chen, Shuo; Weitemier, Adam Z.; Zeng, Xiao; He, Linmeng; Wang, Xiyu; Tao, Yanqiu; Huang, Arthur J. Y.; Hashimotodani, Yuki; Kano, Masanobu; Iwasaki, Hirohide; Parajuli, Laxmi Kumar; Okabe, Shigeo; Teh, Daniel B. Loong; All, Angelo H.; Tsutsui-Kimura, Iku; Tanaka, Kenji F.; Liu, Xiaogang; McHugh, Thomas J.

2018-02-01

Optogenetics has revolutionized the experimental interrogation of neural circuits and holds promise for the treatment of neurological disorders. It is limited, however, because visible light cannot penetrate deep inside brain tissue. Upconversion nanoparticles (UCNPs) absorb tissue-penetrating near-infrared (NIR) light and emit wavelength-specific visible light. Here, we demonstrate that molecularly tailored UCNPs can serve as optogenetic actuators of transcranial NIR light to stimulate deep brain neurons. Transcranial NIR UCNP-mediated optogenetics evoked dopamine release from genetically tagged neurons in the ventral tegmental area, induced brain oscillations through activation of inhibitory neurons in the medial septum, silenced seizure by inhibition of hippocampal excitatory cells, and triggered memory recall. UCNP technology will enable less-invasive optical neuronal activity manipulation with the potential for remote therapy.

Reducing local traffic emissions at urban intersection using ITS countermeasures

NARCIS (Netherlands)

Mahmod, M.; Arem, B. van; Pueboobpaphan, R.; Lange, R. de

2013-01-01

In many countries traffic emissions have significantly increased during the last two decades because of the increased number of vehicles. As such, traffic emissions have become the main source of air pollution in urban areas, where breaches of the EU limit values frequently occur. To reduce these

The smoking ban next door: do hospitality businesses in border areas have reduced sales after a statewide smoke-free policy?

Science.gov (United States)

Klein, Elizabeth G; Hood, Nancy E

2015-01-01

Despite numerous studies demonstrating no significant economic effects on hospitality businesses following a statewide smoke-free (SF) policy, regional concerns suggest that areas near states without SF policies may experience a loss of hospitality sales across the border. The present study evaluated the impact of Ohio's statewide SF policy on taxable restaurant and bar sales in border and non-border areas. Spline regression analysis was used to assess changes in monthly taxable sales at the county level in full-service restaurants and bars in Ohio. Data were analyzed from four years prior to policy implementation to three years post-policy. Change in the differences in the slope of taxable sales for border (n = 21) and non-border (n = 67) counties were evaluated for changes following the statewide SF policy enforcement, adjusted for unemployment rates, general trends in the hospitality sector, and seasonality. After adjusting for covariates, there was no statistically significant change in the difference in slope for taxable sales for either restaurants (β = 0.9, p = 0.09) or bars (β = 0.2, p = 0.07) following the SF policy for border areas compared to non-border areas of Ohio. Border regions in Ohio did not experience a significant change in bar and restaurant sales compared to non-border areas following a statewide SF policy. Results support that Ohio's statewide SF policy did not impact these two areas differently, and provide additional evidence for the continued use of SF policies to provide protection from exposure to secondhand smoke for both workers and the general public. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

Ultimate Opening Combined with Area Stability Applied to Urban Scenes

OpenAIRE

Marcotegui , Beatriz; Serna , Andrés; Hernández , Jorge

2017-01-01

International audience; This paper explores the use of ultimate opening in urban analysis context. It demonstrates the efficiency of this approach for street level elevation images, derived from 3D point clouds acquired by terrestrial mobile mapping systems. An area-stability term is introduced in the residual definition, reducing the over-segmentation of the vegetation while preserving small significant regions. We compare two possible combinations of the Ultimate Opening and the Area Stabil...

Novel Area Optimization in FPGA Implementation Using Efficient VHDL Code

OpenAIRE

Zulfikar, Z

2012-01-01

A new novel method for area efficiency in FPGA implementation is presented. The method is realized through flexibility and wide capability of VHDL coding. This method exposes the arithmetic operations such as addition, subtraction and others. The design technique aim to reduce occupies area for multi stages circuits by selecting suitable range of all value involved in every step of calculations. Conventional and efficient VHDL coding methods are presented and the synthesis result is compared....

Age-related effects on leaf area/sapwood area relationships, canopy transpiration and carbon gain of Norway spruce stands (Picea abies) in the Fichtelgebirge, Germany.

Science.gov (United States)

Köstner, B; Falge, E; Tenhunen, J D

2002-06-01

Stand age is an important structural determinant of canopy transpiration (E(c)) and carbon gain. Another more functional parameter of forest structure is the leaf area/sapwood area relationship, A(L)/A(S), which changes with site conditions and has been used to estimate leaf area index of forest canopies. The interpretation of age-related changes in A(L)/A(S) and the question of how A(L)/A(S) is related to forest functions are of current interest because they may help to explain forest canopy fluxes and growth. We conducted studies in mature stands of Picea abies (L.) Karst. varying in age from 40 to 140 years, in tree density from 1680 to 320 trees ha(-1), and in tree height from 15 to 30 m. Structural parameters were measured by biomass harvests of individual trees and stand biometry. We estimated E(c) from scaled-up xylem sap flux of trees, and canopy-level fluxes were predicted by a three-dimensional microclimate and gas exchange model (STANDFLUX). In contrast to pine species, A(L)/A(S) of P. abies increased with stand age from 0.26 to 0.48 m(2) cm(-2). Agreement between E(c) derived from scaled-up sap flux and modeled canopy transpiration was obtained with the same parameterization of needle physiology independent of stand age. Reduced light interception per leaf area and, as a consequence, reductions in net canopy photosynthesis (A(c)), canopy conductance (g(c)) and E(c) were predicted by the model in the older stands. Seasonal water-use efficiency (WUE = A(c)/E(c)), derived from scaled-up sap flux and stem growth as well as from model simulation, declined with increasing A(L)/A(S) and stand age. Based on the different behavior of age-related A(L)/A(S) in Norway spruce stands compared with other tree species, we conclude that WUE rather than A(L)/A(S) could represent a common age-related property of all species. We also conclude that, in addition to hydraulic limitations reducing carbon gain in old stands, a functional change in A(L)/A(S) that is related to

LOCAL ACTION GROUPS - THE EUROPEAN INTEGRATION CATALYST FOR THE ROMANIAN RURAL AREA

Directory of Open Access Journals (Sweden)

Mosora Liviu - Cosmin

2011-07-01

Full Text Available Romania has the highest share of European Union rural areas (44.9% in 2009, which generates and maintains a long series of regional disparities. Because of these disparities, the economy faces a number of elements that undermine the quality of human and social capital and reduces the potential for growth: precarious social and economic infrastructure, reduced access to markets and thus to goods, a low level of both economic cohesion and living standards, and a difficult access to education and training (leading to the underutilization of labor in rural areas, while major shortages in the labor market and increased migration phenomenon manifests.\\r\

A Novel Method of Fabricating Flexible Transparent Conductive Large Area Graphene Film

International Nuclear Information System (INIS)

Fan Tian-Ju; Yuan Chun-Qiu; Tang Wei; Tong Song-Zhao; Huang Wei; Min Yong-Gang; Liu Yi-Dong; Epstein, Arthur J.

2015-01-01

We fabricate flexible conductive and transparent graphene films on position-emission-tomography substrates and prepare large area graphene films by graphite oxide sheets with the new technical process. The multi-layer graphene oxide sheets can be chemically reduced by HNO 3 and HI to form a highly conductive graphene film on a substrate at lower temperature. The reduced graphene oxide sheets show a high conductivity sheet with resistance of 476 Ω/sq and transmittance of 76% at 550 nm (6 layers). The technique used to produce the transparent conductive graphene thin film is facile, inexpensive, and can be tunable for a large area production applied for electronics or touch screens. (paper)

Wellbeing impacts of city policies for reducing greenhouse gas emissions

DEFF Research Database (Denmark)

Hiscock, Rosemary; Mudu, Pierpaolo; Braubach, Matthias

2014-01-01

To mitigate climate change, city authorities are developing policies in areas such as transportation, housing and energy use, to reduce greenhouse gas emissions. In addition to their effects on greenhouse gas emissions, these policies are likely to have consequences for the wellbeing...... and subjective aspects which can be measured quantitatively; our review of measures informs the development of a theoretical model linking wellbeing to policies which cities use to reduce greenhouse gas emissions. Finally, we discuss the extent to which the links proposed in the conceptual model are supported...

Deformations of temporary wooden supports used to reduce building deflections in mining areas

Science.gov (United States)

Gromysz, Krzysztof

2018-04-01

Temporary supports, consisting of a stack of wooden elements and a hydraulic jack, are used in the process of removing deflections in buildings with one to three aboveground floors in mining areas. During uneven raising, the supports are loaded monotonically, unloaded and loaded cyclically. Laboratory tests were designed for the supports. For the investigated range of loads of 0 to 400 kN, under a growing load, a linear relationship exists between a load and the change in the stack length, which signifies that the deformations of wooden elements and displacements related to their mutual interactions increase proportionally. A seemingly higher stack stiffness is seen at the beginning of the unloading process and for cyclical loads, meaning that in this phase of loading, the material deformation of the wooden elements and the jack is responsible for changing the jack length in this load phase, with a negligible presence of mutual displacements of wooden elements. The support, after being unloaded, returns to the initial position and its permanent deformations are not observed. The stiffness of a temporary support decreases as the height of the stack of wooden elements increases.

Deformations of temporary wooden supports used to reduce building deflections in mining areas

Directory of Open Access Journals (Sweden)

Gromysz Krzysztof

2018-01-01

Full Text Available Temporary supports, consisting of a stack of wooden elements and a hydraulic jack, are used in the process of removing deflections in buildings with one to three aboveground floors in mining areas. During uneven raising, the supports are loaded monotonically, unloaded and loaded cyclically. Laboratory tests were designed for the supports. For the investigated range of loads of 0 to 400 kN, under a growing load, a linear relationship exists between a load and the change in the stack length, which signifies that the deformations of wooden elements and displacements related to their mutual interactions increase proportionally. A seemingly higher stack stiffness is seen at the beginning of the unloading process and for cyclical loads, meaning that in this phase of loading, the material deformation of the wooden elements and the jack is responsible for changing the jack length in this load phase, with a negligible presence of mutual displacements of wooden elements. The support, after being unloaded, returns to the initial position and its permanent deformations are not observed. The stiffness of a temporary support decreases as the height of the stack of wooden elements increases.

Reduced graphite oxide in supercapacitor electrodes.

Science.gov (United States)

Lobato, Belén; Vretenár, Viliam; Kotrusz, Peter; Hulman, Martin; Centeno, Teresa A

2015-05-15

The current energy needs have put the focus on highly efficient energy storage systems such as supercapacitors. At present, much attention focuses on graphene-like materials as promising supercapacitor electrodes. Here we show that reduced graphite oxide offers a very interesting potential. Materials obtained by oxidation of natural graphite and subsequent sonication and reduction by hydrazine achieve specific capacitances as high as 170 F/g in H2SO4 and 84F/g in (C2H5)4NBF4/acetonitrile. Although the particle size of the raw graphite has no significant effect on the physico-chemical characteristics of the reduced materials, that exfoliated from smaller particles (materials may suffer from a drop in their specific surface area upon fabrication of electrodes with features of the existing commercial devices. This should be taken into account for a reliable interpretation of their performance in supercapacitors. Copyright © 2015 Elsevier Inc. All rights reserved.

Estimation of solar collector area for water heating in buildings of Malaysia

Science.gov (United States)

Manoj Kumar, Nallapaneni; Sudhakar, K.; Samykano, M.

2018-04-01

Solar thermal energy (STE) utilization for water heating at various sectorial levels became popular and still growing especially for buildings in the residential area. This paper aims to study and identify the solar collector area needed based on the user requirements in an efficient manner. A step by step mathematical approach is followed to estimate the area in Sq. m. Four different cases each having different hot water temperatures (45°, 50°C, 55°C, and 60°C) delivered by the solar water heating system (SWHS) for typical residential application at Kuala Lumpur City, Malaysia is analysed for the share of hot and cold water mix. As the hot water temperature levels increased the share of cold water mix is increased to satisfy the user requirement temperature, i.e. 40°C. It is also observed that as the share of hot water mix is reduced, the collector area can also be reduced. Following this methodology at the installation stage would help both the user and installers in the effective use of the solar resource.

Amphetamine Self-Administration Attenuates Dopamine D2 Autoreceptor Function

Science.gov (United States)

Calipari, Erin S; Sun, Haiguo; Eldeeb, Khalil; Luessen, Deborah J; Feng, Xin; Howlett, Allyn C; Jones, Sara R; Chen, Rong

2014-01-01

Dopamine D2 autoreceptors located on the midbrain dopaminergic neurons modulate dopamine (DA) neuron firing, DA release, and DA synthesis through a negative-feedback mechanism. Dysfunctional D2 autoreceptors following repeated drug exposure could lead to aberrant DA activity in the ventral tegmental area (VTA) and projection areas such as nucleus accumbens (NAcc), promoting drug-seeking and -taking behavior. Therefore, it is important to understand molecular mechanisms underlying drug-induced changes in D2 autoreceptors. Here, we reported that 5 days of amphetamine (AMPH) self-administration reduced the ability of D2 autoreceptors to inhibit DA release in the NAcc as determined by voltammetry. Using the antibody-capture [35S]GTPγS scintillation proximity assay, we demonstrated for the first time that midbrain D2/D3 receptors were preferentially coupled to Gαi2, whereas striatal D2/D3 receptors were coupled equally to Gαi2 and Gαo for signaling. Importantly, AMPH abolished the interaction between Gαi2 and D2/D3 receptors in the midbrain while leaving striatal D2/D3 receptors unchanged. The disruption of the coupling between D2/D3 receptors and Gαi2 by AMPH is at least partially explained by the enhanced RGS2 (regulator of G-protein signaling 2) activity resulting from an increased RGS2 trafficking to the membrane. AMPH had no effects on the midbrain expression and trafficking of other RGS proteins such as RGS4 and RGS8. Our data suggest that midbrain D2/D3 receptors are more susceptible to AMPH-induced alterations. Reduced D2 autoreceptor function could lead to enhanced DA signaling and ultimately addiction-related behavior. RGS2 may be a potential non-dopaminergic target for pharmacological intervention of dysfunctional DA transmission and drug addiction. PMID:24513972

Global Warming: The Instability of Desert Climate is Enhancing in the Northwest Area in China: A Case Study in the Desert Area in Northwestern China

OpenAIRE

Zhao-Feng Chang; Shu-Juan Zhu; Fu-Gui Han; Sheng-Nnian Zhong; Qiang-Qiang Wang; Jian-Hui Zhang

2013-01-01

To disclose the relation between the sandstorms change and the temperature changes, a case study in the desert area in northwestern china is investigated. The results showed that: the instability of climate in Minqin desert area is enhancing in the arid desert region in northwest China. Mainly as follows: Variation the annual extreme maximum temperature increasing. Variation of extreme minimum temperature also an increasing trend. Average visibility of sandstorms significantly reduced and the...

THE WIDESPREAD OF Fe(III)-REDUCING BACTERIA IN NATURAL ECOSYSTEMS OF ECUADOR.

Science.gov (United States)

Tashyrev, O B; Govorukha, V M

2015-01-01

The widespread of Fe(III)-reducing microorganisms in natural ecosystems of Ecuador of La Favorita, Tungurahua volcano and Papallacta areas was experimentally proved. High efficiency of microbial precipitation of soluble iron compounds was also demonstrated. Obtained results indicate the potential ability of Fe(III)-reducing microorganisms to influence the formation of carbon and iron vector fluxes in ecosystems, as well as development of effective biotechnologies of water purification from iron compounds.

Reducing the local environmental impacts of passenger transport

Energy Technology Data Exchange (ETDEWEB)

Maentynen, J.; Kalenoja, H.; Maekelae, S. [Tampere Univ. of Technology (Finland). Inst. of Transportation Engineering

1995-12-31

The local injurious effects of traffic appear mostly in densely populated areas, where the demand for transport is high. The local environmental effects of transportation can be reduced by measures of urban planning, traffic planning, vehicle technology and economical restrictions. Land use planning, concentration of urban structure and promoting distance working are examples of expedients of urban planning. The methods of urban planning usually affect very slowly on transport structure, but they also have a significant and continuous influence on travel demand. The methods of traffic planning generally tend to increase the fluency of traffic flow or reduce private car traffic with diverse restrictions by supporting environmentally more favourable vehicles or modes of travel. The improvements in vehicle technology can be significant in the short run. By economical regulations it is possible to guide the demand for traffic to a desirable direction. The local injurious effects of traffic vary by the size of urban areas. Local conditions, such as urban structure, population density, structure of employment, and composition of transport structure, influence on travel pattern and modal split. In Tampere University of Technology several measures to reduce environmental effects and energy consumption of transportation has been evaluated. This article presents three types of categories. As technological measures the introduction of electric vehicles and the alternative bus fuels have been studied. In addition, the effects of introducing midibuses, the car pool system and the increasing of vehicle occupancy have been evaluated as measures, which generally increase transportation system efficiency. (author)

Reducing the local environmental impacts of passenger transport

Energy Technology Data Exchange (ETDEWEB)

Maentynen, J; Kalenoja, H; Maekelae, S [Tampere Univ. of Technology (Finland). Inst. of Transportation Engineering

1996-12-31

The local injurious effects of traffic appear mostly in densely populated areas, where the demand for transport is high. The local environmental effects of transportation can be reduced by measures of urban planning, traffic planning, vehicle technology and economical restrictions. Land use planning, concentration of urban structure and promoting distance working are examples of expedients of urban planning. The methods of urban planning usually affect very slowly on transport structure, but they also have a significant and continuous influence on travel demand. The methods of traffic planning generally tend to increase the fluency of traffic flow or reduce private car traffic with diverse restrictions by supporting environmentally more favourable vehicles or modes of travel. The improvements in vehicle technology can be significant in the short run. By economical regulations it is possible to guide the demand for traffic to a desirable direction. The local injurious effects of traffic vary by the size of urban areas. Local conditions, such as urban structure, population density, structure of employment, and composition of transport structure, influence on travel pattern and modal split. In Tampere University of Technology several measures to reduce environmental effects and energy consumption of transportation has been evaluated. This article presents three types of categories. As technological measures the introduction of electric vehicles and the alternative bus fuels have been studied. In addition, the effects of introducing midibuses, the car pool system and the increasing of vehicle occupancy have been evaluated as measures, which generally increase transportation system efficiency. (author)

The Role of Quality Obstetric Care Services on Reducing Maternal ...

African Journals Online (AJOL)

The study recommends that, special initiative should be done to bring changes on reducing maternal mortality, such as ensure essential equipments and ... Enforcement in providing quality of obstetric care services in maternal health services especially in rural areas where majority of people in Tanzania reside is not an ...

Regional urban area extraction using DMSP-OLS data and MODIS data

International Nuclear Information System (INIS)

Zhang, X Y; Cai, C; Li, P J

2014-01-01

Stable night lights data from Defense Meteorological Satellite Program (DMSP) Operational Line-scan System (OLS) provide a unique proxy for anthropogenic development. This paper proposed two new methods of extracting regional urban extents using DMSP-OLS data, MODIS NDVI data and Land Surface Temperature (LST) data. MODIS NDVI data were used to reduce the over-glow effect, since urban areas generally have lower vegetation index values than the surrounding areas (e.g. agricultural and forest areas). On the other hand, urban areas generally show higher surface temperatures than the surrounding areas. Since urban area is the only class of interest, a one-class classifier, the One-Class Support Vector Machine (OCSVM), was selected as the classifier. The first method is classification of different data combinations for mapping: (1) OLS data and NDVI data, (2) OLS data and LST data, and (3) OLS data, NDVI data and LST data combined. The second one is a morphological reconstruction based method which combines classification results from OLS plus NDVI data and from OLS plus LST data. In the morphological reconstruction based method, the classification result using OLS and NDVI data was used as a mask image, while the classification result using OLS and LST data was used as a marker image. The north China area covering 14 provinces was selected as study area. Classification results from Landsat TM/ETM+ data from selected areas with different development levels were used as reference data to validate the proposed methods. The results show that the proposed methods effectively reduced the over-glow effect caused by DSMP-OLS data and achieved better results compared to the results from the traditional thresholding technique. The combination of all three datasets produces more accurate results than those of using any two datasets. The proposed morphological reconstruction based method achieves the best result in urban extent mapping

Rod-coating: towards large-area fabrication of uniform reduced graphene oxide films for flexible touch screens.

Science.gov (United States)

Wang, Jie; Liang, Minghui; Fang, Yan; Qiu, Tengfei; Zhang, Jin; Zhi, Linjie

2012-06-05

A novel strategy is developed for the large-scale fabrication of reduced graphene oxide films directly on flexible substrates in a controlled manner by the combination of a rod-coating technique and room-temperature reduction of graphene oxide. The as-prepared films display excellent uniformity, good transparency and conductivity, and great flexibility in a touch screen. Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

The tuberal lateral hypothalamus is a major target for GABAA--but not GABAB-mediated control of food intake.

Science.gov (United States)

Turenius, Christine I; Charles, Jonathan R; Tsai, Donna H; Ebersole, Priscilla L; Htut, Myat H; Ngo, Phuong T; Lara, Raul N; Stanley, B Glenn

2009-08-04

The lateral hypothalamus (LH) is a site of integration for control mechanisms of feeding behavior as it has extensive reciprocal connections with multiple intrahypothalamic and extrahypothalamic brain areas. Evidence suggests that blockade of ionotropric gamma-aminobutyric acid (GABA) receptors in the LH elicits eating in satiated rats. To determine whether this GABA(A) receptor antagonist effect is specific to the LH, the antagonist picrotoxin was injected into one of six nearby sites and food intake was measured. Picrotoxin at 133 pmol elicited eating in the LH, but not in surrounding sites (thalamus, lateral preoptic area, ventral tegmental area, dorsomedial hypothalamus, and entopeduncular nucleus). More specifically, picrotoxin injected into the tuberal LH (tLH) elicited eating, but was ineffective when injected into the anterior or posterior LH. We also investigated whether GABA(B) receptors in the LH participated in the control of food intake and found that neither blockade nor activation of these receptors under multiple conditions changed food intake. Collectively, our findings suggest that GABA(A) but not GABA(B) receptors in the tLH act to suppress feeding behavior.

An Efficient Vital Area Identification Method

International Nuclear Information System (INIS)

Jung, Woo Sik

2017-01-01

A new Vital Area Identification (VAI) method was developed in this study for minimizing the burden of VAI procedure. It was accomplished by performing simplification of sabotage event trees or Probabilistic Safety Assessment (PSA) event trees at the very first stage of VAI procedure. Target sets and prevention sets are calculated from the sabotage fault tree. The rooms in the shortest (most economical) prevention set are selected and protected as vital areas. All physical protection is emphasized to protect these vital areas. All rooms in the protected area, the sabotage of which could lead to core damage, should be incorporated into sabotage fault tree. So, sabotage fault tree development is a very difficult task that requires high engineering costs. IAEA published INFCIRC/225/Rev.5 in 2011 which includes principal international guidelines for the physical protection of nuclear material and nuclear installations. A new efficient VAI method was developed and demonstrated in this study. Since this method drastically reduces VAI problem size, it provides very quick and economical VAI procedure. A consistent and integrated VAI procedure had been developed by taking advantage of PSA results, and more efficient VAI method was further developed in this study by inserting PSA event tree simplification at the initial stage of VAI procedure.

Fiber to the serving area: telephone-like star architecture for CATV

Science.gov (United States)

Fellows, David M.

1992-02-01

CATV systems traditionally use a tree and branch architecture to bring up to 550 MHz of analog bandwidth to every home in a franchise area. This changed slightly with the advent of AM fiber optic equipment, as fiber optics were used in an overlay fashion to reduce coaxial amplifier cascades and improve subscriber quality and reliability. Within the last year, fiber has economically replaced coaxial trunking. The resulting fiber to the serving area architecture combines fiber and coaxial stars for a network that looks much like the carrier serving area architectures used by telephone companies.

Food hoarding, but not food intake, is attenuated by acute diazepam treatment in female Mongolian gerbils (Meriones unguiculatus).

Science.gov (United States)

Yang, Hui-Di; Wang, Qian; Wang, De-Hua

2014-06-01

This article is part of a Special Issue "Energy Balance". Effects of γ-aminobutyric acid (GABA) on food hoarding are unknown in rodents, and the effects of energy balance and GABA have not been evaluated in females. To evaluate the role of food deprivation and GABA on food hoarding, female Mongolian gerbils were given i.p. injection of diazepam (1mg/kg and 3mg/kg, respectively), a GABAA receptor agonist. Among food-deprived females, there was a bimodal pattern in the frequency of gerbils with different levels of food hoarding. High food hoarding (HFH) and low food hoarding (LFH) gerbils were analyzed. Diazepam blocked food deprivation-induced food hoarding in HFH gerbils, but not in LFH gerbils. This blockade was associated with increased cellular activation in selected brain areas, such as the nucleus accumbens (NAcc), caudate putamen (CP) and ventral tegmental area (VTA), which suggested that direct activation of GABA in the brain reward circuitry decreased food hoarding in HFH females. Moreover, diazepam increased Fos expression in field CA2 and CA3 of the hippocampus, but had no significant effect on Fos expression in field CA1 and dentate gyrus (DG) of the hippocampus, indicating that the hippocampus has area-specific effects on food hoarding in HFH gerbils. Diazepam did not alter food intake in both HFH and LFH gerbils. In addition, serum corticosterone concentrations were higher in the HFH than in the LFH ones. Together, these data indicated that food deprivation increased food hoarding in female gerbils, diazepam reduced food deprivation-induced food hoarding in HFH gerbils, and that GABA might influence food hoarding via classical reward circuitry via the mesolimbic dopamine system and specific hippocampal areas. Copyright © 2014 Elsevier Inc. All rights reserved.

A comparison on the heat load of HTS current leads with respect to uniform and non-uniform cross-sectional areas

Energy Technology Data Exchange (ETDEWEB)

Han, Seung Hak; Nam, Seok Ho; Lee, Je Yull; Song, Seung Hyun; Jeon, Hae Ryong; Baek, Geon Woo; Ko, Tae Kuk [Yonsei University, Seoul (Korea, Republic of); Kang, Hyoung Ku [Korea National University of Transportation, Chungju (Korea, Republic of)

2017-09-15

Current lead is a device that connects the power supply and superconducting magnets. High temperature superconductor (HTS) has lower thermal conductivity and higher current density than normal metal. For these reasons, the heat load can be reduced by replacing the normal metal of the current lead with the HTS. Conventional HTS current lead has same cross-sectional area in the axial direction. However, this is over-designed at the cold-end (4.2 K) in terms of current. The heat load can be reduced by reducing this part because the heat load is proportional to the cross-sectional area. Therefore, in this paper, heat load was calculated from the heat diffusion equation of HTS current leads with uniform and non-uniform cross-sectional areas. The cross-sectional area of the warm-end (65K) is designed considering burnout time when cooling system failure occurs. In cold-end, Joule heat and heat load due to current conduction occurs at the same time, so the cross-sectional area where the sum of the two heat is minimum is obtained. As a result of simulation, current leads for KSTAR TF coils with uniform and non-uniform cross-sectional areas were designed, and it was confirmed that the non-uniform cross-sectional areas could further reduce the heat load.

300 Area Disturbance Report

Energy Technology Data Exchange (ETDEWEB)

LL Hale; MK Wright; NA Cadoret

1999-01-07

The objective of this study was to define areas of previous disturbance in the 300 Area of the U.S. Department of Energy (DOE) Hanford Site to eliminate these areas from the cultural resource review process, reduce cultural resource monitoring costs, and allow cultural resource specialists to focus on areas where subsurface disturbance is minimal or nonexistent. Research into available sources suggests that impacts from excavations have been significant wherever the following construction activities have occurred: building basements and pits, waste ponds, burial grounds, trenches, installation of subsurface pipelines, power poles, water hydrants, and well construction. Beyond the areas just mentioned, substrates in the' 300 Area consist of a complex, multidimen- sional mosaic composed of undisturbed stratigraphy, backfill, and disturbed sediments; Four Geographic Information System (GIS) maps were created to display known areas of disturbance in the 300 Area. These maps contain information gleaned from a variety of sources, but the primary sources include the Hanford GIS database system, engineer drawings, and historic maps. In addition to these maps, several assumptions can be made about areas of disturbance in the 300 Area as a result of this study: o o Buried pipelines are not always located where they are mapped. As a result, cultural resource monitors or specialists should not depend on maps depicting subsurface pipelines for accurate locations of previous disturbance. Temporary roads built in the early 1940s were placed on layers of sand and gravel 8 to 12 in. thick. Given this information, it is likely that substrates beneath these early roads are only minimally disturbed. Building foundations ranged from concrete slabs no more than 6 to 8 in. thick to deeply excavated pits and basements. Buildings constructed with slab foundations are more numerous than may be expected, and minimally disturbed substrates may be expected in these locations. Historic

Semiconductor technology for reducing emissions and increasing efficiency

Energy Technology Data Exchange (ETDEWEB)

Duffin, B.; Frank, R. [Motorola Semiconductor Products Sector, Phoenix, AZ (United States)

1997-12-31

The cooperation and support of all industries are required to significantly impact a worldwide reduction in gaseous emissions that may contribute to climate change. Each industry also is striving to more efficiently utilize the resources that it consumes since this is both conservation for good citizenship and an intelligent approach to business. The semiconductor industry is also extremely concerned with these issues. However, semiconductor manufacturer`s products provide solutions for reduced emissions and increased efficiency in their industry, other industries and areas that can realize significant improvements through control technology. This paper will focus on semiconductor technologies of digital control, power switching and sensing to improve efficiency and reduce emissions in automotive, industrial, and office/home applications. 10 refs., 13 figs.

Small area estimation of child undernutrition in Ethiopian woredas

DEFF Research Database (Denmark)

Sohnesen, Thomas Pave; Ambel, Alemayehu Azeze; Fisker, Peter Kielberg

2017-01-01

Reducing child undernutrition is a key social policy objective of the Ethiopian government. Despite substantial reduction over the last decade and a half, child undernutrition is still high; with 48 percent of children either stunted, underweight or wasted, undernutrition remains an important child....... The estimates are small area estimations based on the 2014 Demographic and Health Survey and the latest population census. It is shown that small area estimations are powerful predictors of undernutrition, even compared to household characteristics, such as wealth and education, and hence a valuable targeting...

Lighting in the shackling area: conciliating broiler welfare with labor comfort

Directory of Open Access Journals (Sweden)

GO Adamczuk

2014-06-01

Full Text Available The objective of this study was to investigate if blue lighting could reduce broiler stress and comply with legal labor comfort requirements in a new shackling area of a middle-size processing plant. In this study, the old shackling area was compared with the new area, where a blue lighting system was designed and implemented according to the regulations. The old and new areas were video- and audio-recorded during the shackling of 33,850 broilers in each area. Data were statistically analyzed using the non-parametric test of Wilcoxon-Mann-Whitney (w test.The results indicated 56% reduction in wing-flapping and 3.2% noise reduction in the new area. These results were obtained by increasing 119% lighting at the work stations in the shackling area, allowing workers to handle the birds more carefully, which may improve processing plant productivity. The study demonstrated that it is possible to conciliate better animal welfare with visual comfort for workers in the shackling area.

Modelling mitigation options to reduce diffuse nitrogen water pollution from agriculture.

Science.gov (United States)

Bouraoui, Fayçal; Grizzetti, Bruna

2014-01-15

Agriculture is responsible for large scale water quality degradation and is estimated to contribute around 55% of the nitrogen entering the European Seas. The key policy instrument for protecting inland, transitional and coastal water resources is the Water Framework Directive (WFD). Reducing nutrient losses from agriculture is crucial to the successful implementation of the WFD. There are several mitigation measures that can be implemented to reduce nitrogen losses from agricultural areas to surface and ground waters. For the selection of appropriate measures, models are useful for quantifying the expected impacts and the associated costs. In this article we review some of the models used in Europe to assess the effectiveness of nitrogen mitigation measures, ranging from fertilizer management to the construction of riparian areas and wetlands. We highlight how the complexity of models is correlated with the type of scenarios that can be tested, with conceptual models mostly used to evaluate the impact of reduced fertilizer application, and the physically-based models used to evaluate the timing and location of mitigation options and the response times. We underline the importance of considering the lag time between the implementation of measures and effects on water quality. Models can be effective tools for targeting mitigation measures (identifying critical areas and timing), for evaluating their cost effectiveness, for taking into consideration pollution swapping and considering potential trade-offs in contrasting environmental objectives. Models are also useful for involving stakeholders during the development of catchments mitigation plans, increasing their acceptability. © 2013.

Novel Area Optimization in FPGA Implementation Using Efficient VHDL Code

Directory of Open Access Journals (Sweden)

. Zulfikar

2012-10-01

Full Text Available A new novel method for area efficiency in FPGA implementation is presented. The method is realized through flexibility and wide capability of VHDL coding. This method exposes the arithmetic operations such as addition, subtraction and others. The design technique aim to reduce occupies area for multi stages circuits by selecting suitable range of all value involved in every step of calculations. Conventional and efficient VHDL coding methods are presented and the synthesis result is compared. The VHDL code which limits range of integer values is occupies less area than the one which is not. This VHDL coding method is suitable for multi stage circuits.

Novel Area Optimization in FPGA Implementation Using Efficient VHDL Code

Directory of Open Access Journals (Sweden)

Zulfikar .

2015-05-01

Full Text Available A new novel method for area efficiency in FPGA implementation is presented. The method is realized through flexibility and wide capability of VHDL coding. This method exposes the arithmetic operations such as addition, subtraction and others. The design technique aim to reduce occupies area for multi stages circuits by selecting suitable range of all value involved in every step of calculations. Conventional and efficient VHDL coding methods are presented and the synthesis result is compared. The VHDL code which limits range of integer values is occupies less area than the one which is not. This VHDL coding method is suitable for multi stage circuits.

Settlement to Improve Water Quality in Delaware River, Philadelphia-Area Creeks

Science.gov (United States)

EPA and the U.S. Department of Justice have reached agreement with a major water utility in the greater Philadelphia area to significantly reduce sewage discharges to the Delaware River and local creeks.

Lipid reducing activity and toxicity profiles of a library of polyphenol derivatives.

Science.gov (United States)

Urbatzka, Ralph; Freitas, Sara; Palmeira, Andreia; Almeida, Tiago; Moreira, João; Azevedo, Carlos; Afonso, Carlos; Correia-da-Silva, Marta; Sousa, Emilia; Pinto, Madalena; Vasconcelos, Vitor

2018-05-10

Obesity is an increasing epidemic worldwide and novel treatments are urgently needed. Polyphenols are natural compounds derived from plants, which are known in particular for their antioxidant properties. However, some polyphenols were described to possess anti-obesity activities in vitro and in vivo. In this study, we aimed to screen a library of 85 polyphenol derivatives for their lipid reducing activity and toxicity. Compounds were analyzed at 5 μM with the zebrafish Nile red fluorescence fat metabolism assay and for general toxicity in vivo. To improve the safety profile, compounds were screened at 50 μM in murine preadipocytes in vitro for cytotoxicity. Obtained activity data were used to create a 2D-QSAR (quantitative structure activity relationship) model. 38 polyphenols showed strong lipid reducing activity. Toxicity analysis revealed that 18 of them did not show any toxicity in vitro or in vivo. QSAR analysis revealed the importance of the number of rings, fractional partial positively charged surface area, relative positive charge, relative number of oxygen atoms, and partial negative surface area for lipid-reducing activity. The five most potent compounds with EC 50 values in the nanomolar range for lipid reducing activity and without any toxic effects are strong candidates for future research and development into anti-obesity drugs. Molecular profiling for fasn, sirt1, mtp and ppary revealed one compound that reduced significantly fasn mRNA expression. Copyright © 2018 Elsevier Masson SAS. All rights reserved.

Increasing corn for biofuel production reduces biocontrol services in agricultural landscapes

NARCIS (Netherlands)

Landis, D.A.; Gardiner, M.M.; Werf, van der W.; Swinton, S.M.

2008-01-01

Increased demand for corn grain as an ethanol feedstock is altering U. S. agricultural landscapes and the ecosystem services they provide. From 2006 to 2007, corn acreage increased 19% nationally, resulting in reduced crop diversity in many areas. Biological control of insects is an ecosystem

Omah displacement and utilization from rural to urban areas, as green design lifestyle

Science.gov (United States)

Fajarwati, Ade Ariyani Sari

2017-11-01

Building a house in urban area is very costly and also leaving a bunch amount of construction waste. Many efforts were made to reduce the load of this waste. However, the high demand of residences in metropolitan makes the waste problem needs to be solved together. Based on this problem, author chooses Omah, - a Javanese traditional house, which is built, based on the traditional system of life of Javanese people - displacement from rural to urban area as the alternative solution, as it uses selected materials from nature by considering the sustainability and preservation for future generation. The wooden building is built based on traditional construction system that follows Javanese principles and traditional calculation, based on philosophy and cosmology in the community. This paper will covers utilization of Omah in urban area as an implementation of green design, which refers to the concepts of reuse, reduce, recycle and responsibility. Through expert interviews and field surveys in urban and rural areas, author collected data needed for this paper. Although the functionality of the building is different from rural to urban requirements, the phenomenon of Omah displacement from Javanese habitat to urban living area is well accepted and becomes an interesting trend.

Selected cost considerations for geothermal district heating in existing single-family residential areas

Energy Technology Data Exchange (ETDEWEB)

Rafferty, Kevin

1996-06-01

In the past, district heating (geothermal or conventionally fueled) has not been widely applied to the single-family residential sector. Low-heat load density is the commonly cited reason for this. Although it's true that load density in these areas is much lower than for downtown business districts, other frequently overlooked factors may compensate for load density. In particular, costs for distribution system installation can be substantially lower in some residential areas due to a variety of factors. This reduced development cost may partially compensate for the reduced revenue resulting from low-load density. This report examines cost associated with the overall design of the system (direct or indirect system design), distribution piping installation, and customer branch lines. It concludes with a comparison of the costs for system development and the revenue from an example residential area.

Will nuclear power plant standardization reduce the licensing impact on construction

International Nuclear Information System (INIS)

Allen, J.M.; Bingham, W.G.; Keith, D.G.

1976-01-01

The NRC and the nuclear industry have been pursuing standardization quite vigorously in an effort to reduce the cost and schedule for the design and construction of nuclear power plants. The NRC is currently reviewing standard plant applications submitted under each of four standardization options. In addition, the NRC has published Standard Review Plans and Standard Technical Specifications. Although problems exist in the implementation of standardization and in areas unaffected by standardization, each of these standardization methods has the potential to reduce the licensing impact on construction

Red maca (Lepidium meyenii reduced prostate size in rats

Directory of Open Access Journals (Sweden)

Rubio Julio

2005-01-01

Full Text Available Abstract Background Epidemiological studies have found that consumption of cruciferous vegetables is associated with a reduced risk of prostate cancer. This effect seems to be due to aromatic glucosinolate content. Glucosinolates are known for have both antiproliferative and proapoptotic actions. Maca is a cruciferous cultivated in the highlands of Peru. The absolute content of glucosinolates in Maca hypocotyls is relatively higher than that reported in other cruciferous crops. Therefore, Maca may have proapoptotic and anti-proliferative effects in the prostate. Methods Male rats treated with or without aqueous extracts of three ecotypes of Maca (Yellow, Black and Red were analyzed to determine the effect on ventral prostate weight, epithelial height and duct luminal area. Effects on serum testosterone (T and estradiol (E2 levels were also assessed. Besides, the effect of Red Maca on prostate was analyzed in rats treated with testosterone enanthate (TE. Results Red Maca but neither Yellow nor Black Maca reduced significantly ventral prostate size in rats. Serum T or E2 levels were not affected by any of the ecotypes of Maca assessed. Red Maca also prevented the prostate weight increase induced by TE treatment. Red Maca administered for 42 days reduced ventral prostatic epithelial height. TE increased ventral prostatic epithelial height and duct luminal area. These increases by TE were reduced after treatment with Red Maca for 42 days. Histology pictures in rats treated with Red Maca plus TE were similar to controls. Phytochemical screening showed that aqueous extract of Red Maca has alkaloids, steroids, tannins, saponins, and cardiotonic glycosides. The IR spectra of the three ecotypes of Maca in 3800-650 cm (-1 region had 7 peaks representing 7 functional chemical groups. Highest peak values were observed for Red Maca, intermediate values for Yellow Maca and low values for Black Maca. These functional groups correspond among others to benzyl

Large-area metallic photonic lattices for military applications.

Energy Technology Data Exchange (ETDEWEB)

Luk, Ting Shan

2007-11-01

In this project we developed photonic crystal modeling capability and fabrication technology that is scaleable to large area. An intelligent optimization code was developed to find the optimal structure for the desired spectral response. In terms of fabrication, an exhaustive survey of fabrication techniques that would meet the large area requirement was reduced to Deep X-ray Lithography (DXRL) and nano-imprint. Using DXRL, we fabricated a gold logpile photonic crystal in the <100> plane. For the nano-imprint technique, we fabricated a cubic array of gold squares. These two examples also represent two classes of metallic photonic crystal topologies, the connected network and cermet arrangement.

Can (ReCentralization Be a Modern Governance in Rural Areas?

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István BALÁZS

2017-02-01

Full Text Available Concentration and recentralization can be described as a European trend in the fi eld of local governance, especially in the fi eld of the administration of rural areas. An important tool of the concentration of the local administration is the intercommunal cooperation. The Hungarian rural areas have fragmented spatial structures. Because of the fragmentation and the small number of the voluntary associations these types of local cooperation were signifi cantly supported by the central budget in the 1990s and 2000s. The economic crisis resulted in a strong concentration trend in Hungary, as well. The new Hungarian Municipal Code introduced a Janus-faced model. The administration of the rural areas was strongly concentrated by the establishment of the mandatory common municipal offi ces of the small villages (under 2000 inhabitants while the forms of the intercommunal associations were simplifi ed. This reform reduced the number of local offi ces signifi cantly. This type of intercommunal cooperation became the main form of the j oined public service management as well, because the former signifi cant state aid of the voluntary associations has been reduced.

Can (ReCentralization Be a Modern Governance in Rural Areas?

Directory of Open Access Journals (Sweden)

István BALÁZS

2017-02-01

Full Text Available Concentration and recentralization can be described as a European trend in the fi eld of local governance, especially in the fi eld of the administration of rural areas. An important tool of the concentration of the local administration is the intercommunal cooperation. The Hungarian rural areas have fragmented spatial structures. Because of the fragmentation and the small number of the voluntary associations these types of local cooperation were signifi cantly supported by the central budget in the 1990s and 2000s. The economic crisis resulted a strong concentration trend in Hungary, as well. The new Hungarian Municipal Code introduced a Janus-faced model. The administration of the rural areas was strongly concentrated by the establishment of the mandatory common municipal offi ces of the small villages (under 2000 inhabitants while the forms of the intercommunal associations were simplifi ed. This reform reduced the number of local offi ces signifi cantly. This type of intercommunal cooperation became the main form of the j oined public service management as well, because the former signifi cant state aid of the voluntary associations have been reduced.

An appraisal of ground water for irrigation in the Wadena area, central Minnesota

Science.gov (United States)

Lindholm, F.G.

1970-01-01

The Wadena area is part of a large sandy plain in central Minnesota whose soils have low water-holding capacity. Drought conditions which adversely affect plant growth frequently occur in the summer when moisture is most needed. To reduce the risk of crop failure in the area supplemental irrigation is on the increase.

[Evaluation of strategies aimed at reducing the level of noise in different areas of neonatal care in a tertiary hospital].

Science.gov (United States)

Nieto-Sanjuanero, Adriana; Quero-Jiménez, José; Cantú-Moreno, Daniel; Rodríguez-Balderrama, Isaías; Montes-Tapia, Fernando; Rubio-Pérez, Nadina; Treviño-Garza, Consuelo; de la O-Cavazos, Manuel

2015-01-01

To determine the noise levels of different areas responsible for newborn care, develop intervention strategies to decrease the noise, and evaluate its effectiveness. Prospective, observational and longitudinal study carried out using a sonometer, measuring sound levels for three weeks in the neonatal intensive care unit (NICU), neonatal intermediate care unit (UCIREN), delivery (TOCO QX) and nursery (CUNERO) units. We implemented an intervention program and subsequent measurements were performed under the same initial conditions. When comparing the decibel levels in different areas during the three weeks, pre- and post-intervention, we found at the neonatal intensive care unit 59.9±4.8 vs. 56.4±4.7 dB (pTOCO QX, so the intervention program was effective in these areas; however, the decibel levels registered continue above those recommended by international standards.

Reductive Dissolution of Goethite and Hematite by Reduced Flavins

Energy Technology Data Exchange (ETDEWEB)

Shi, Zhi; Zachara, John M.; Wang, Zheming; Shi, Liang; Fredrickson, Jim K.

2013-10-02

The abiotic reductive dissolution of goethite and hematite by the reduced forms of flavin mononucleotide (FMNH2) and riboflavin (RBFH2), electron transfer mediators (ETM) secreted by the dissimilatory iron-reducing bacterium Shewanella, was investigated under stringent anaerobic conditions. In contrast to the rapid redox reaction rate observed for ferrihydrite and lepidocrocite (Shi et al., 2012), the reductive dissolution of crystalline goethite and hematite was slower, with the extent of reaction limited by the thermodynamic driving force at circumneutral pH. Both the initial reaction rate and reaction extent increased with decreasing pH. On a unit surface area basis, goethite was less reactive than hematite between pH 4.0 and 7.0. AH2DS, the reduced form of the well-studied synthetic ETM anthraquinone-2,6-disulfonate (AQDS), yielded higher rates than FMNH2 under most reaction conditions, despite the fact that FMNH2 was a more effective reductant than AH2DS for ferryhydrite and lepidocrocite. Two additional model compounds, methyl viologen and benzyl viologen, were investigated under similar reaction conditions to explore the relationship between reaction rate and thermodynamic properties. Relevant kinetic data from the literature were also included in the analysis to span a broad range of half-cell potentials. Other conditions being equal, the surface area normalized initial reaction rate (ra) increased as the redox potential of the reductant became more negative. A non-linear, parabolic relationship was observed between log ra and the redox potential for eight reducants at pH 7.0, as predicted by Marcus theory for electron transfer. When pH and reductant concentration were fixed, log ra was positively correlated to the redox potential of four Fe(III) oxides over a wide pH range, following a non-linear parabolic relationship as well.

Policies for reduced deforestation and their impact on agricultural production.

Science.gov (United States)

Angelsen, Arild

2010-11-16

Policies to effectively reduce deforestation are discussed within a land rent (von Thünen) framework. The first set of policies attempts to reduce the rent of extensive agriculture, either by neglecting extension, marketing, and infrastructure, generating alternative income opportunities, stimulating intensive agricultural production or by reforming land tenure. The second set aims to increase either extractive or protective forest rent and--more importantly--create institutions (community forest management) or markets (payment for environmental services) that enable land users to capture a larger share of the protective forest rent. The third set aims to limit forest conversion directly by establishing protected areas. Many of these policy options present local win-lose scenarios between forest conservation and agricultural production. Local yield increases tend to stimulate agricultural encroachment, contrary to the logic of the global food equation that suggests yield increases take pressure off forests. At national and global scales, however, policy makers are presented with a more pleasant scenario. Agricultural production in developing countries has increased by 3.3-3.4% annually over the last 2 decades, whereas gross deforestation has increased agricultural area by only 0.3%, suggesting a minor role of forest conversion in overall agricultural production. A spatial delinking of remaining forests and intensive production areas should also help reconcile conservation and production goals in the future.

Neuromodulation can reduce aggressive behavior elicited by violent video games.

Science.gov (United States)

Riva, Paolo; Gabbiadini, Alessandro; Romero Lauro, Leonor J; Andrighetto, Luca; Volpato, Chiara; Bushman, Brad J

2017-04-01

Research has shown that exposure to violent media increases aggression. However, the neural underpinnings of violent-media-related aggression are poorly understood. Additionally, few experiments have tested hypotheses concerning how to reduce violent-media-related aggression. In this experiment, we focused on a brain area involved in the regulation of aggressive impulses-the right ventrolateral prefrontal cortex (rVLPFC). We tested the hypothesis that brain polarization through anodal transcranial direct current stimulation (tDCS) over rVLPFC reduces aggression related to violent video games. Participants (N = 79) were randomly assigned to play a violent or a nonviolent video game while receiving anodal or sham stimulation. Afterward, participants aggressed against an ostensible partner using the Taylor aggression paradigm (Taylor Journal of Personality, 35, 297-310, 1967), which measures both unprovoked and provoked aggression. Among those who received sham stimulation, unprovoked aggression was significantly higher for violent-game players than for nonviolent-game players. Among those who received anodal stimulation, unprovoked aggression did not differ for violent- and nonviolent-game players. Thus, anodal stimulation reduced unprovoked aggression in violent-game players. No significant effects were found for provoked aggression, suggesting tit-for-tat responding. This experiment sheds light on one possible neural underpinning of violent-media-related aggression-the rVLPFC, a brain area involved in regulating negative feelings and aggressive impulses.

Bioremediation: Effectiveness in reducing the ecological impact

International Nuclear Information System (INIS)

Scholten, M.C.T.

1992-01-01

Bioremediation becomes an important technique in oil spill combat programmes. The purpose is to shorten the exposure time of biota to oil compounds, in order to reduce long term environmental effects. Although bioremediation products have the advantage of stimulating the natural capacity to degrade oil, there are some limitations to be considered. Application as a technique for first emergency actions following an oil spill is not effective, and can therefore be no alternative for dispersion or mechanical removal of floating or freshly stranded oil slicks. Acute toxic effects are related to the short term exposure to unweathered oils. An immediate removal of oil is necessary to reduce the extent of the environmental impact of an oil spill. Physical processes (transport, dilution and evaporation) are determining the initial fate of environmentally released oil. Biodegradation only becomes important as a process of removing oil in the next phase. It is the only effective way to further reduce the concentration of oil that is left in (intertidal) coastal areas. Bioremediation thus reduces the duration of the environmental impact of an oil spill. This is especially important in ecosystems with a low recovery potential (e.g., salt marshes, rocky shores). The experimental evaluation of bioremediation products is mainly based on the capacity to reduce fresh oil and the acute toxicity of the product itself, rather than on the capacity to enhance the further reduction of weathered oil and the toxicological consequences of higher release rates of intermediate metabolites produced during the biotransformation processes

Psychological contracts: a new strategy for retaining reduced-hour physicians.

Science.gov (United States)

Hartwell, Jennifer K

2010-01-01

As a retention strategy, healthcare organizations offer reduced-hour schedules to physicians seeking better work-family balance. However, this quantitative study of 94 full-time and reduced-hour female physicians in the Boston area found that working fewer hours helps physicians achieve better balance but does not improve their burnout or career satisfaction, or impact their intention to quit or leave the field of medicine. Instead, the findings demonstrate that psychological contract fulfillment, which reflects the subjective nature of the employment relationship, is more important than work hours, an objective job condition, in predicting intention to quit and these other outcomes. A fine-grained analysis is initiated uncovering the multidimensionality of the psychological contract construct. To integrate successful reduced-hour arrangements for physicians, medical managers are directed to the importance of understanding the composition of reduced-hour physicians' psychological contracts, specifically, their need to do challenging work, receive high levels of supervisor support, and promotion opportunities.

Analysis of area level and unit level models for small area estimation in forest inventories assisted with LiDAR auxiliary information.

Science.gov (United States)

Mauro, Francisco; Monleon, Vicente J; Temesgen, Hailemariam; Ford, Kevin R

2017-01-01

Forest inventories require estimates and measures of uncertainty for subpopulations such as management units. These units often times hold a small sample size, so they should be regarded as small areas. When auxiliary information is available, different small area estimation methods have been proposed to obtain reliable estimates for small areas. Unit level empirical best linear unbiased predictors (EBLUP) based on plot or grid unit level models have been studied more thoroughly than area level EBLUPs, where the modelling occurs at the management unit scale. Area level EBLUPs do not require a precise plot positioning and allow the use of variable radius plots, thus reducing fieldwork costs. However, their performance has not been examined thoroughly. We compared unit level and area level EBLUPs, using LiDAR auxiliary information collected for inventorying 98,104 ha coastal coniferous forest. Unit level models were consistently more accurate than area level EBLUPs, and area level EBLUPs were consistently more accurate than field estimates except for large management units that held a large sample. For stand density, volume, basal area, quadratic mean diameter, mean height and Lorey's height, root mean squared errors (rmses) of estimates obtained using area level EBLUPs were, on average, 1.43, 2.83, 2.09, 1.40, 1.32 and 1.64 times larger than those based on unit level estimates, respectively. Similarly, direct field estimates had rmses that were, on average, 1.37, 1.45, 1.17, 1.17, 1.26, and 1.38 times larger than rmses of area level EBLUPs. Therefore, area level models can lead to substantial gains in accuracy compared to direct estimates, and unit level models lead to very important gains in accuracy compared to area level models, potentially justifying the additional costs of obtaining accurate field plot coordinates.

Science summary in support of Manatee Protection Area (MPA) design in Puerto Rico

Science.gov (United States)

Drew, C. Ashton; Alexander-Vaughn, Louise B.; Collazo, Jaime A.

2012-01-01

The Antillean manatee (Trichechus manatus manatus), a subspecies of the West Indian manatee, is listed as endangered by the US Department of Interior. In accordance with its listing, the U.S. Fish and Wildlife Service’s Caribbean Field Office (USFWS) is mandated to create one or more Manatee Protection Areas (MPAs) for Puerto Rico. Designation of these areas must comply with the legal definition of an MPA’s purpose: to prevent or reduce take of manatees (CFR 50: 44 FR 60964, Oct. 22, 1979). To meet this goal, we pursued two objectives: 1) identify areas which include the specific ecological attributes necessary to support manatee populations, and 2) identify areas where take can be reduced through approved MPA regulatory frameworks. We achieved these objectives through literature review, expert elicitation, and geospatial modeling. This report delivers to USFWS a set of nine potential MPA regions. These regions represent the spatial realization of experts’ hypotheses regarding manatee requirements and threats, and the potential to implement MPA strategies (e.g. watercraft access, speed regulations, signage and boater education). The nine regions are compared based on a number of factors, including their potential to reduce take, quality of the habitat encompassed, and total area. These maps and statistics serve as suitable starting points to select one or more MPA sites, but we recommend that the mapped attributes and threats (i.e., boating activity) of MPAs be ground-truthed to visually confirm the local presence of resources, threats, and manatees before any area is selected. Once established, the effectiveness of MPAs can be monitored and updated through processes of adaptive monitoring and management. Aerial surveys, radio tracking studies, and public surveys are all valuable tools to assess the success of an MPA. Establishing MPAs is a management action that, integrated within the species Recovery Plan, should enhance the conservation of manatees.

Reducing flicker due to ambient illumination in camera captured images

Science.gov (United States)

Kim, Minwoong; Bengtson, Kurt; Li, Lisa; Allebach, Jan P.

2013-02-01

The flicker artifact dealt with in this paper is the scanning distortion arising when an image is captured by a digital camera using a CMOS imaging sensor with an electronic rolling shutter under strong ambient light sources powered by AC. This type of camera scans a target line-by-line in a frame. Therefore, time differences exist between the lines. This mechanism causes a captured image to be corrupted by the change of illumination. This phenomenon is called the flicker artifact. The non-content area of the captured image is used to estimate a flicker signal that is a key to being able to compensate the flicker artifact. The average signal of the non-content area taken along the scan direction has local extrema where the peaks of flicker exist. The locations of the extrema are very useful information to estimate the desired distribution of pixel intensities assuming that the flicker artifact does not exist. The flicker-reduced images compensated by our approach clearly demonstrate the reduced flicker artifact, based on visual observation.

Developing conservation governance strategies: holistic management of protected areas in Nepal

OpenAIRE

Budhathoki, Prabhu

2012-01-01

The Buffer Zone (BZ) concept has been introduced in Nepal as a key component of the national biodiversity conservation strategy to mitigate the impacts of protected areas on local communities, and thereby reduce adverse impacts of local people on protected areas. Unlike traditional Buffer Zone programmes which are mostly limited to creating a protective layer and/or distributing economic benefits to local people, the Buffer Zone management approach in Nepal integrates livelihoods and conserva...

OPERATIONAL RESTRICTIONS FOR REDUCING NOISE AND THE SAFETY OF AIR OPERATIONS

Directory of Open Access Journals (Sweden)

Anna KWASIBORSKA

2017-03-01

Full Text Available Many European airports are located in close proximity to residential or protected areas. Aircraft noise emissions caused by the landing and taking off of aircraft are a big problem in these areas. From an operational point of view, the method for reducing noise is to reduce traffic volume or change its organization, especially during the night. Some procedures and tools have been developed to support air traffic management in the implementation of operational constraints necessary to maintain noise at an acceptable level. The objective of this paper is to analyse the effectiveness of these tools. For this purpose, we have analysed existing methods of operational noise reduction, taking into account their influence on the structure, smoothness, punctuality and, especially, the safety of air traffic. As a result, existing risks have been identified, while methods have been proposed to combine two important air traffic service tasks: ensuring safety, while taking into account the environmental constraints, especially in relation to the acoustic climate.

Evaluation of four designs of short implants placed in atrophic areas with reduced bone height: a three-year, retrospective, clinical and radiographic study.

Science.gov (United States)

Lopez Torres, J A; Gehrke, S A; Calvo Guirado, J L; Aristazábal, L F R

2017-09-01

The aim of the present study was to evaluate retrospectively the clinical and radiographic behaviour of four commercially-available short implants with different macrodesigns and microdesigns in areas in which the height of the bone was reduced. We took into account the success and survival, peri-implant crestal bone loss, and the level of probing at which the gum bled. Patients were included if they had been given one or more short implants (≤8.5mm long) in the posterior jaws at least three years earlier. Three hundred and ninety-one short implants were placed in 170 subjects, and were divided in four groups based on the brand of implant. The implants were evaluated one, two, and three years after they had been inserted. Short implants had a three-year survival and success rate of 90% in all groups, and bone loss was acceptable after three years with no significant differences between them. These results support the use of short implants as an effective and safe treatment. However, within the limitations of this study, the design of the implant does seem to influence the behaviour of peri-implant bone at the crestal level. Copyright © 2017. Published by Elsevier Ltd.

Urbanization Reduces Transfer of Diverse Environmental Microbiota Indoors

Directory of Open Access Journals (Sweden)

Anirudra Parajuli

2018-02-01

Full Text Available Expanding urbanization is a major factor behind rapidly declining biodiversity. It has been proposed that in urbanized societies, the rarity of contact with diverse environmental microbiota negatively impacts immune function and ultimately increases the risk for allergies and other immune-mediated disorders. Surprisingly, the basic assumption that urbanization reduces exposure to environmental microbiota and its transfer indoors has rarely been examined. We investigated if the land use type around Finnish homes affects the diversity, richness, and abundance of bacterial communities indoors. Debris deposited on standardized doormats was collected in 30 rural and 26 urban households in and near the city of Lahti, Finland, in August 2015. Debris was weighed, bacterial community composition determined by high throughput sequencing of bacterial 16S ribosomal RNA (rRNA gene on the Illumina MiSeq platform, and the percentage of four different land use types (i.e., built area, forest, transitional, and open area within 200 m and 2000 m radiuses from each household was characterized. The quantity of doormat debris was inversely correlated with coverage of built area. The diversity of total bacterial, Proteobacterial, Actinobacterial, Bacteroidetes, and Firmicutes communities decreased as the percentage of built area increased. Their richness followed the same pattern except for Firmicutes for which no association was observed. The relative abundance of Proteobacteria and particularly Gammaproteobacteria increased, whereas that of Actinobacteria decreased with increasing built area. Neither Phylum Firmicutes nor Bacteroidetes varied with coverage of built area. Additionally, the relative abundance of potentially pathogenic bacterial families and genera increased as the percentage of built area increased. Interestingly, having domestic animals (including pets only altered the association between the richness of Gammaproteobacteria and diversity of

Reduced functional connectivity between V1 and inferior frontal cortex associated with visuomotor performance in autism.

Science.gov (United States)

Villalobos, Michele E; Mizuno, Akiko; Dahl, Branelle C; Kemmotsu, Nobuko; Müller, Ralph-Axel

2005-04-15

Some recent evidence has suggested abnormalities of the dorsal stream and possibly the mirror neuron system in autism, which may be responsible for impairments of joint attention, imitation, and secondarily for language delays. The current study investigates functional connectivity along the dorsal stream in autism, examining interregional blood oxygenation level dependent (BOLD) signal cross-correlation during visuomotor coordination. Eight high-functioning autistic men and eight handedness and age-matched controls were included. Visually prompted button presses were performed with the preferred hand. For each subject, functional connectivity was computed in terms of BOLD signal correlation with the mean time series in bilateral visual area 17. Our hypothesis of reduced dorsal stream connectivity in autism was only in part confirmed. Functional connectivity with superior parietal areas was not significantly reduced. However, the autism group showed significantly reduced connectivity with bilateral inferior frontal area 44, which is compatible with the hypothesis of mirror neuron defects in autism. More generally, our findings suggest that dorsal stream connectivity in autism may not be fully functional.

The agony of unemployment in the Euro Area

Directory of Open Access Journals (Sweden)

Ristanović Vladimir

2014-01-01

Full Text Available This paper looks at the evolution of the unemployment problem in the Euro Area. Our goal is to look at what are the roots of the unemployment problem and to devise reasons of the already chronic unemployment problem. We show the main factors that prolong the agony of unemployment and whether it is likely that in the near future, the problem of unemployment in the Euro Area will bi past. In the Euro Area we follow the analysis of basic macroeconomic indicators of balance in an economy - GDP, inflation and unemployment. We consider whether the monetary strategy of inflation targeting has contributed to the unemployment problem, by reducing the potential output, but also to confirm that within the current global crisis there are some deviations from the theoretical concepts of basic macroeconomic relationships - Okun's law and the Phillips curve. We show that only Germany, with a 'small' sacrifice, can save the real sector in the peripheral Mediterranean countries, as well as in the entire Euro Area.

Opioid receptors in midbrain dopaminergic regions of the rat. 1. Mu receptor autoradiography

International Nuclear Information System (INIS)

German, D.C.; Speciale, S.G.; Manaye, K.F.; Sadeq, M.

1993-01-01

Several lines of evidence indicate that an interaction exists between opioid peptides and midbrain dopaminergic neurons. The purpose of this study was to map and quantify the density of the mu opioid receptor subtype relative to the location of the dopaminergic (DA) neurons in the retrorubral field (nucleus A8), substantia nigra (nucleus A9), and ventral tegmental area and related nuclei (nucleus A10) in the rat. Sections through the rostral-caudal extent of the midbrain were stained with an antibody against tyrosine hydroxylase, as a DA cell marker, and comparable sections were processed for in vitro receptor autoradiography using the mu-selective ligand, 3 H-Tyr-D-Ala-N-MePhe-Gyl-ol enkephalin. In the nucleus A8 region, there were low levels of mu binding. In the rostral portion of nucleus A9, there was prominent mu binding both in the ventral pars compacta, which contains numerous DA neurons, and in regions that correspond to the location of the DA dendrites which project ventrally into the underlying substantia nigra pars reticulata. In the caudal portion of nucleus A9, mu binding was greatest in the substantia nigra pars reticulata, but also in the same region that contains DA neurons. In nucleus A10, mu receptor densities differed depending upon the nucleus A10 subdivision, and the rostral-caudal position in the nucleus. Low receptor densities were observed in rostral portions of the ventral tegmental area and interfascicular nucleus, and there was negligible binding in the parabrachial pigmented nucleus and paranigral nucleus at the level of the interpeduncular nucleus; all regions where there are high densities of DA somata. Mu binding was relatively high in the central linear nucleus, and in the dorsal and medial divisions of the medial terminal nucleus of the accessory optic system, which has been shown to contain DA dendrites. These data indicate that mu opioid receptors are located in certain regions occupied by all three midbrain DA nuclei, but in a

Beyond the Inventory: An Interagency Collaboration to Reduce Greenhouse Gas Emissions in the Greater Yellowstone Area

Energy Technology Data Exchange (ETDEWEB)

Kandt, A.; Hotchkiss, E.; Fiebig, M.

2010-10-01

As one of the largest, intact ecosystems in the continental United States, land managers within the Greater Yellowstone Area (GYA) have recognized the importance of compiling and understanding agency greenhouse gas (GHG) emissions. The 10 Federal units within the GYA have taken an active role in compiling GHG inventories on a unit- and ecosystem-wide level, setting goals for GHG mitigation, and identifying mitigation strategies for achieving those goals. This paper details the processes, methodologies, challenges, solutions, and lessons learned by the 10 Federal units within the GYA throughout this ongoing effort.

Initiatives towards Carbon Neutrality in the Helsinki Metropolitan Area

Directory of Open Access Journals (Sweden)

Karna Dahal

2016-07-01

Full Text Available Carbon neutrality represents one climate strategy adopted by many cities, including the city of Helsinki and the Helsinki metropolitan area in Finland. This study examines initiatives adopted by the Helsinki metropolitan area aimed at reducing energy-related carbon emissions and achieving carbon neutrality through future actions. Various sectorial energy consumption rates per year and carbon emissions from various sectors within the city of Helsinki and the metropolitan area were extracted from an online database and re-calculated (in GWh, MWh/inhabitant and MtCO2e, KtCO2e/inhabitant. We employed a backcasting scenario method to explore the various carbon reduction measures in the Helsinki metropolitan area. About 96% of the emissions produced in the Helsinki metropolitan area are energy-based. District heating represents the primary source of emissions, followed by transportation and electricity consumption, respectively. We also found that accomplishing the carbon reduction strategies of the Helsinki metropolitan area by 2050 remains challenging. Technological advancement for clean and renewable energy sources, smart policies and raising awareness resulting in behavioral changes greatly affect carbon reduction actions. Thus, strong political commitments are also required to formulate and implement stringent climate actions.

Effects of Cotyledon Area and Gibberellin A3 on Photoperiodic Flower Induction in Pharbitis nil Seedlings

OpenAIRE

Ogawa, Yukiyoshi; 小川, 幸持

1993-01-01

The relationship between the cotyledon area reduced before or after an inductive dark period and its photoperiodic response was examined with Pharbitis nil seedlings. Plants with 0.25- to 1-cm2 cotyledon area flowered, showing almost the same critical length of dark period, 11 or 12 h, as is the case with a single intact cotyledon (about 8.5 cm2), but the floral response of plants with reduced cotyledon area did not increase with dark periods longer than 14 h, but it was far greater per unit ...

REDUCING GONAD IRRADIATION IN PEDIATRIC DIAGNOSIS

Science.gov (United States)

Bishop, Harry A.; Webber, Milo; O'Loughlin, Bernard J.

1959-01-01

The greatest danger of carcinogenesis and of genetic damage through diagnostic radiologic procedures is in children, whose smaller bodies are more vulnerable and who have a longer life span in which this damage can be realized. Film badges placed on the gonad area during radiologic studies indicated widely varying degrees of gonad irradiation from similar procedures. These results emphasize the importance of technique in protecting children from unnecessary exposure. Such exposure can be reduced by greater beam filtration, use of higher tube potentials, careful beam collimation and centering, closer coning and shielding of the gonads. A new film tested reduced exposure time by 50 per cent. Further reduction was obtained by high-speed screens. A most important measure is avoidance of unnecessary, repetitious and undiagnostic studies. Fluoroscopy should be avoided if possible. If not, the operator must dark-adapt his eyes, use the smallest possible current, the narrowest beam, and the shortest exposure time. Image intensification promotes these aims. Modern equipment, properly shielded, assures against unsuspected exposure. PMID:13618739

40 CFR 1027.120 - Can I qualify for reduced fees?

Science.gov (United States)

2010-07-01

... United States. (2) The full fee for an application for certification for a model year exceeds 1.0% of the... sales area and model year as the requested certificate for the converted vehicle or engine. (3) For... information available at the time of the fee payment. (6) You may submit a reduced fee as described in this...

Increase globe artichoke cropping sustainability using sub-surface drip-irrigation systems in a Mediterranean coastal area for reducing groundwater withdrawal

Science.gov (United States)

Mantino, Alberto; Marchina, Chiara; Bonari, Enrico; Fabbrizzi, Alessandro; Rossetto, Rudy

2017-04-01

suitability of SDI for globe artichoke cultivation, reducing the water consumption, while maintaining (or even increasing) crop production and (ii) assess the crop water use efficiency respect to surface drip-irrigation. The field test is located in Venturina (Italy) and it covers a surface of 4 ha. The soil is characterized by sandy-loam texture, 1.72% of organic matter at 7.81 pH. Groundwater is the main source of supply for irrigation. By the chemical point of view, a monitoring campaign in spring 2016 showed a neutral pH of 7.2, electrical conductivity of 1363 μS/cm, 373 and 243 mg/l of total sulphate and carbonate, respectively, thus demonstrating the suitability of groundwater for SDI application. The SDI system was implemented at the beginning of September 2016. The sub-surface buried pipelines, were placed at 0.25 m depth, with emitters spaced 0.5 m. The distance between pipelines was 1.5 m, according to globe artichoke layout (1.5 m between rows, 1 m in-row spacing). Surface-buried tubes were placed in an area about 0.75 ha wide for the comparison with SDI. Artichoke var. Terom were transplanted after the SDI operation test. In the next 3 years, both crop productivity and water use will be assessed. Results will be presented and discussed with the whole farmer's community. Acknowledgement This paper is presented within the framework of the project LIFE REWAT, which has received funding from the LIFE Programme of the European Union Grant Agreement LIFE14 ENV/IT/001290.

Refinement of the list of constituents for groundwater monitoring at M-area

International Nuclear Information System (INIS)

Wells, D.G.

1997-11-01

For several years Westinghouse Savannah River Company (WSRC) has been examining ways of reducing monitoring costs. Most of these efforts have been aimed at reducing the number of wells sampled or reducing sample frequency. With regards to monitoring around the M-Area Settling Basin, we are now examining a possible reduction in the number of constituents analyzed. Constituents that can be dropped entirely are nonhazardous inorganics generally referred to as water quality indicators. Monitoring for these parameters is sensible when a facility is in detection monitoring, but it is much less useful at a facility like the M-Area Basin. The water quality indicators are helpful in detecting whether or not a facility has impacted the environment. But their concentrations are not important in themselves. At M-Area, it is well documented that the facility has impacted groundwater quite seriously with a known group of hazardous constituents. So the concentrations of the nonhazardous constituents are of little interest. At M-Area there are 41 Point of Compliance (POC) wells monitoring an area of about .25 square miles and about 236 plume definition wells monitoring the surround 4 square miles. The POC wells form a picket line around the facility and are intended to detect any constituents leaching from it. They are also intended to determine whether such constituents exceed action levels. Plume definition wells are added to define the plume created a particular set or subset of contaminants. The M-Area plume definition wells were installed in several phases over a ten year time span as SRS struggled to define the extent of a large plume of TCE and PCE. These wells were not located for the purpose of monitoring the numerous inorganics and radionuclides on the unit's monitoring list. Many of the inorganics and radionuclides are relatively immobile in groundwater and cannot be expected to appear in the widely scattered TCE/PCE plume definition wells

Large area x-ray detectors for cargo radiography

Science.gov (United States)

Bueno, C.; Albagli, D.; Bendahan, J.; Castleberry, D.; Gordon, C.; Hopkins, F.; Ross, W.

2007-04-01

Large area x-ray detectors based on phosphors coupled to flat panel amorphous silicon diode technology offer significant advances for cargo radiologic imaging. Flat panel area detectors provide large object coverage offering high throughput inspections to meet the high flow rate of container commerce. These detectors provide excellent spatial resolution when needed, and enhanced SNR through low noise electronics. If the resolution is reduced through pixel binning, further advances in SNR are achievable. Extended exposure imaging and frame averaging enables improved x-ray penetration of ultra-thick objects, or "select-your-own" contrast sensitivity at a rate many times faster than LDAs. The areal coverage of flat panel technology provides inherent volumetric imaging with the appropriate scanning methods. Flat panel area detectors have flexible designs in terms of electronic control, scintillator selection, pixel pitch, and frame rates. Their cost is becoming more competitive as production ramps up for the healthcare, nondestructive testing (NDT), and homeland protection industries. Typically used medical and industrial polycrystalline phosphor materials such as Gd2O2S:Tb (GOS) can be applied to megavolt applications if the phosphor layer is sufficiently thick to enhance x-ray absorption, and if a metal radiator is used to augment the quantum detection efficiency and reduce x-ray scatter. Phosphor layers ranging from 0.2-mm to 1-mm can be "sandwiched" between amorphous silicon flat panel diode arrays and metal radiators. Metal plates consisting of W, Pb or Cu, with thicknesses ranging from 0.25-mm to well over 1-mm can be used by covering the entire area of the phosphor plate. In some combinations of high density metal and phosphor layers, the metal plate provides an intensification of 25% in signal due to electron emission from the plate and subsequent excitation within the phosphor material. This further improves the SNR of the system.

Can Urban Trees Reduce the Impact of Climate Change on Storm Runoff?

Directory of Open Access Journals (Sweden)

Katarina ZABRET

2015-11-01

Full Text Available The process of urbanisation leads to significant changes in surface cover, which influence the hydrological properties of an area. The infiltration of precipitation into the soil is reduced, so that both surface water runoff and the velocity at which water travels have increased drastically. In recent decades climate change has also been observed to affect precipitation trends. Many studies have shown that the amount of rainfall is increasing and that heavy rainfall events are becoming more frequent. These changes are producing more runoff, which has to be drained. Urban trees can reduce the amount of precipitation reaching the ground due to rainfall interception, and are becoming increasingly recognized as an effective means for the regulation of storm water volumes and costs. The study measured rainfall interception in an urban area. It shows that Betula pendula can intercept 20.6% of annual rainfall, whereas Pinus nigra could intercept as much as 51.0% of annual rainfall. The advantage of rainfall interception was shown in the case of a parking lot where the planting of trees was able to reduce runoff by up to 17%.

How is ozone pollution reducing our food supply?

Science.gov (United States)

Wilkinson, Sally; Mills, Gina; Illidge, Rosemary; Davies, William J

2012-01-01

Ground-level ozone pollution is already decreasing global crop yields (from ∼2.2-5.5% for maize to 3.9-15% and 8.5-14% for wheat and soybean, respectively), to differing extents depending on genotype and environmental conditions, and this problem is predicted to escalate given climate change and increasing ozone precursor emissions in many areas. Here a summary is provided of how ozone pollution affects yield in a variety of crops, thus impacting global food security. Ozone causes visible injury symptoms to foliage; it induces early senescence and abscission of leaves; it can reduce stomatal aperture and thereby carbon uptake, and/or directly reduce photosynthetic carbon fixation; it can moderate biomass growth via carbon availability or more directly; it can decrease translocation of fixed carbon to edible plant parts (grains, fruits, pods, roots) due either to reduced availability at source, redirection to synthesis of chemical protectants, or reduced transport capabilities via phloem; decreased carbon transport to roots reduces nutrient and water uptake and affects anchorage; ozone can moderate or bring forward flowering and induce pollen sterility; it induces ovule and/or grain abortion; and finally it reduces the ability of some genotypes to withstand other stresses such as drought, high vapour pressure deficit, and high photon flux density via effects on stomatal control. This latter point is emphasized here, given predictions that atmospheric conditions conducive to drought formation that also give rise to intense precursor emission events will become more severe over the coming decades.

Area Completion Strategies at Savannah River Site: Characterization for Closure and Beyond

International Nuclear Information System (INIS)

Bagwell, Laura; O'Quinn, Sadika; Amidon, Mark

2008-01-01

During the first four decades of its 56 year existence, the Savannah River Site (SRS) was a key supplier of nuclear material for national defense. During the 1990's, the site's primary missions became waste site closure, environmental restoration, and deactivation and decommissioning (D and D) of remnant cold war apparatus. Since 1989, with the approval of State and Federal regulatory agencies and with the participation of interested stakeholders, SRS has implemented a final remedy for a majority of the more than 500 individual waste sites at the former nuclear materials complex. These waste sites range from small, inert rubble pits to large, heavy industrial areas and radioactive waste disposal grounds. The closure and final remediation of these waste sites mark significant progress toward achieving SRS's overarching goal of reducing or eliminating future environmental damage and human health threats. However, larger challenges remain. For example, what are appropriate and achievable end-states for decommissioned nuclear facilities? What environmental and human health risks are associated with these end-states? To answer these questions within the strictures of smaller budgets and accelerated schedules, SRS is implementing an 'area completion' strategy that: - unites several discrete waste units into one conceptual model, - integrates historically disparate environmental characterization and D and D activities - reduces the number of required regulatory documents, - and, in some cases, compresses schedules for achieving a stakeholder-approved end-state. The area completion approaches being implemented at SRS reflect an evolution of the traditional RCRA/ CERCLA remedial process. Area completion strategies: - group waste units and/or D and D facilities together for characterization, remediation, and possible reuse; - identify data needs and integrate data collection activities for D and D, characterization, and remediation; - identify problems that require action

Cabergoline decreases alcohol drinking and seeking behaviors via glial cell line-derived neurotrophic factor.

Science.gov (United States)

Carnicella, Sebastien; Ahmadiantehrani, Somayeh; He, Dao-Yao; Nielsen, Carsten K; Bartlett, Selena E; Janak, Patricia H; Ron, Dorit

2009-07-15

Cabergoline is an ergotamine derivative that increases the expression of glial cell line-derived neurotrophic factor (GDNF) in vitro. We recently showed that GDNF in the ventral tegmental area (VTA) reduces the motivation to consume alcohol. We therefore set out to determine whether cabergoline administration decreases alcohol-drinking and -seeking behaviors via GDNF. Reverse transcription polymerase chain reaction (RT-PCR) and Enzyme-Linked ImmunoSorbent Assay (ELISA) were used to measure GDNF levels. Western blot analysis was used for phosphorylation experiments. Operant self-administration in rats and a two-bottle choice procedure in mice were used to assess alcohol-drinking behaviors. Instrumental performance tested during extinction was used to measure alcohol-seeking behavior. The [35S]GTPgammaS binding assay was used to assess the expression and function of the dopamine D2 receptor (D2R). We found that treatment of the dopaminergic-like cell line SH-SY5Y with cabergoline and systemic administration of cabergoline in rats resulted in an increase in GDNF level and in the activation of the GDNF pathway. Cabergoline treatment decreased alcohol-drinking and -seeking behaviors including relapse, and its action to reduce alcohol consumption was localized to the VTA. Finally, the increase in GDNF expression and the decrease in alcohol consumption by cabergoline were abolished in GDNF heterozygous knockout mice. Together, these findings suggest that cabergoline-mediated upregulation of the GDNF pathway attenuates alcohol-drinking behaviors and relapse. Alcohol abuse and addiction are devastating and costly problems worldwide. This study puts forward the possibility that cabergoline might be an effective treatment for these disorders.

Reducing Community Vulnerability to Wildland Fires in Southern California

Science.gov (United States)

Keeley, J. E.

2010-12-01

underground lines, strategically employing arson patrols during Santa Ana wind events, enforcing regulations on power equipment use in wildland areas, k-rail barriers along roads to reduce fire spread into wildland areas etc. S, or the probability of fire reaching urban environments has historically been the primary focus of state and federal fire management activities. There is a need for greater focus on understanding the most strategic application of wildland fuel treatments. E, the probability of fire encroaching into the urban environment, has largely been addressed in the past by attention to wildland-urban interface (WUI) fuel treatments. The one factor that has perhaps the greatest potential for impacting E are patterns of urban growth, both in strategic placement and spatial patterning within communities, and this is an area where alternative future growth scenarios could have huge impacts on fire outcomes. G, the chance of fire propagating within the urban environment is a function of urban fuels, which include both home construction and landscaping. This area has the potential for effecting large changes in fire losses dependent upon future regulations on plantings in the urban environment.

Long-term toxicity assessment of soils in a recovered area affected by a mining spill

International Nuclear Information System (INIS)

Romero-Freire, A.; García Fernández, I.; Simón Torres, M.; Martínez Garzón, F.J.; Martín Peinado, F.J.

2016-01-01

Residual pollution in the Guadiamar Green Corridor still remains after Aználcollar mine spill in 1998. The polluted areas are identified by the absence of vegetation, soil acidic pH and high concentrations of As, Pb, Zn and Cu. Soil toxicity was assessed by lettuce root elongation and induced soil respiration bioassays. In bare soils, total As and Pb concentrations and water-extractable levels for As, Zn and Cu exceeded the toxicity guidelines. Pollutants responsible for toxicity were different depending on the tested organism, with arsenic being most toxic for lettuce and the metal mixture to soil respiration. Soil properties, such as pH or organic carbon content, are key factors to control metal availability and toxicity in the area. According to our results, there is a risk of pollution to living organisms and the soil quality criteria established in the area should be revised to reduce the risk of toxicity. - Highlights: • 15 years after the Aznalcóllar mine spill residual pollution remains in some areas. • Toxic levels were exceeded for total As and Pb and for soluble As, Zn and Cu. • Metals responsible for soil toxicity are different depending on the tested organism. • pH and organic carbon content reduce metal availability and therefore soil toxicity. • Regulatory guidelines in the area should be revised to reduce the risk of toxicity. - Residual pollution in the Guadiamar Green Corridor remains in some areas after long-term stabilization, with some risk of pollution according to toxicity bioassays.

Effects of Small Oscillations on the Effective Area

International Nuclear Information System (INIS)

Cotroneo, V.; Conconi, P.; Pareschi, G.; Spiga, D.; Tagliaferri, G.; Cusumano, G.

2009-01-01

We analyze the effective area of the Simbol-X mirrors as a function of the off-axis angle for small oscillations. A reduction is expected due to: 1) geometrical effects, because some of the photons miss the secondary mirror surface; 2) reflectivity effects, caused by the variation of the coating reflectivity with the incidence angle. The former are related to the length of the two mirror surfaces, and can be reduced by making the secondary mirror longer. The second ones are energy-dependent, and strongly related to the characteristics of the reflecting coating. These effects are analyzed by means of ray-tracing simulations in order to optimize the mirror and coating design, aiming to improve the effective area stability.

Effects of Small Oscillations on the Effective Area

Science.gov (United States)

Cotroneo, V.; Conconi, P.; Cusumano, G.; Pareschi, G.; Spiga, D.; Tagliaferri, G.

2009-05-01

We analyze the effective area of the Simbol-X mirrors as a function of the off-axis angle for small oscillations. A reduction is expected due to: 1) geometrical effects, because some of the photons miss the secondary mirror surface; 2) reflectivity effects, caused by the variation of the coating reflectivity with the incidence angle. The former are related to the length of the two mirror surfaces, and can be reduced by making the secondary mirror longer. The second ones are energy-dependent, and strongly related to the characteristics of the reflecting coating. These effects are analyzed by means of ray-tracing simulations in order to optimize the mirror and coating design, aiming to improve the effective area stability.

Treatability Test Plan for 300 Area Uranium Stabilization through Polyphosphate Injection

International Nuclear Information System (INIS)

Vermeul, Vince R.; Williams, M. D.; Fritz, Brad G.; Mackley, Rob D.; Mendoza, Donaldo P.; Newcomer, Darrell R.; Rockhold, Mark L.; Williams, Bruce A.; Wellman, Dawn M.

2007-01-01

The U.S. Department of Energy has initiated a study into possible options for stabilizing uranium at the 300 Area using polyphosphate injection. As part of this effort, PNNL will perform bench- and field-scale treatability testing designed to evaluate the efficacy of using polyphosphate injections to reduced uranium concentrations in the groundwater to meet drinking water standards (30 (micro)g/L) in situ. This technology works by forming phosphate minerals (autunite and apatite) in the aquifer that directly sequester the existing aqueous uranium in autunite minerals and precipitates apatite minerals for sorption and long term treatment of uranium migrating into the treatment zone, thus reducing current and future aqueous uranium concentrations. Polyphosphate injection was selected for testing based on technology screening as part of the 300-FF-5 Phase III Feasibility Study for treatment of uranium in the 300-Area

Treatability Test Plan for 300 Area Uranium Stabilization through Polyphosphate Injection

Energy Technology Data Exchange (ETDEWEB)

Vermeul, Vincent R.; Williams, Mark D.; Fritz, Brad G.; Mackley, Rob D.; Mendoza, Donaldo P.; Newcomer, Darrell R.; Rockhold, Mark L.; Williams, Bruce A.; Wellman, Dawn M.

2007-06-01

The U.S. Department of Energy has initiated a study into possible options for stabilizing uranium at the 300 Area using polyphosphate injection. As part of this effort, PNNL will perform bench- and field-scale treatability testing designed to evaluate the efficacy of using polyphosphate injections to reduced uranium concentrations in the groundwater to meet drinking water standards (30 ug/L) in situ. This technology works by forming phosphate minerals (autunite and apatite) in the aquifer that directly sequester the existing aqueous uranium in autunite minerals and precipitates apatite minerals for sorption and long term treatment of uranium migrating into the treatment zone, thus reducing current and future aqueous uranium concentrations. Polyphosphate injection was selected for testing based on technology screening as part of the 300-FF-5 Phase III Feasibility Study for treatment of uranium in the 300-Area.

Reversible brain damage following acute organic solvents' poisoning determined by magnetic resonance

Directory of Open Access Journals (Sweden)

Dujmović Irena

2005-01-01

Full Text Available Introduction. Acute exposure to the effects of volatile solvents is characterized by the abrupt onset of symptoms and signs of poisoning, and relatively fast recovery in the majority of cases. Case report. We report a 24-year-old patient with an acute, accidental poisoning with a mixture of volatile organic solvents (most probably toluene, styrene and xylene, which led to the development of upward gaze paresis, diplopia, hemiparesis, ataxic gate, and the late onset truncal ataxia episodes. After 6 weeks, he recovered completely, while his extensive brain MRI lesions in the caudate nuclei, laterobasal putaminal regions, bilateral anterior insular cortex, central midbrain tegmental area withdrew completely after 4 months. Conclusion. Acute toxic encephalopathy should be a part of the differential diagnosis in any patient with acute neurobehavioral and neurological deficit.

Wheels, skills and thrills: a social marketing trial to reduce aggressive driving from young men in deprived areas.

Science.gov (United States)

Tapp, Alan; Pressley, Ashley; Baugh, Mike; White, Paul

2013-09-01

Young men from poorer backgrounds are associated with high road traffic collision levels. However, solving this problem has proven very difficult. Hence this paper summarises the findings of a UK government funded two-year trial of a cross-discipline intervention to reduce aggressive driving amongst this group. The intervention reported on here departed from traditional approaches such as fear appeals, stand-alone educational approaches, or punitive measures. Instead, the discipline of social marketing was used to provide overarching direction and structure for the trial, with a key focus on motivation and engagement. The project rested on a strong education and training platform and included a bespoke coaching programme, incentives, and an in-vehicle measurement and feedback device. The project had three development phases leading to the final trial. First, a literature and case study review identified possible design strategies. Second, these strategies were explored using primary research in the form of a qualitative inquiry. Third, a pre-trial design phase sought to introduce key components of the intervention to the trial cohort, retaining some flexibility before committing to the final design. Young males with a history of challenging behaviour (e.g. criminal records, driving convictions) from an economically deprived area within a UK city were recruited. Of 42 recruits, 23 successfully completed the trial. Behaviour changes were measured pre-, during and post-trial through a combination of driver performance data measured by in-vehicle data recorders (IVDRs), assessments of driving undertaken by trained observers, and self-assessment surveys and interviews with trial participants. Results indicate a significant average improvement in driving skills amongst participants who completed the trial. Given the difficulty in engaging and changing behaviour of this specific group, this is regarded as a significant finding. In summary the study provides an indication

Household methods to reduce {sup 137}Cs contents of mushrooms

Energy Technology Data Exchange (ETDEWEB)

Kostiainen, E. [Radiation and Nuclear Safety Authority - STUK, Helsinki (Finland)

2005-09-15

High radiocaesium contents in different species of mushrooms have been observed in areas contaminated by radiocaesium deposition after the Chernobyl accident in 1986. There has been no significant reduction in the {sup 137}Cs contents of mushrooms during the past ten years, besides via radioactive decay. The internal radiation dose received via mushrooms can be reduced by processing mushrooms before consumption. Various household methods were studied to find out their efficiency to reduce {sup 137}Cs contents of mushrooms. The methods tested were the same as normally used in cooking. The tests were made for the species of edible mushrooms widely consumed. The retention factors for the treatments tested were in most cases 0.2-0.3. The efficiency of treatments in reducing the {sup 137}Cs contents increased with larger water volumes and prolonged treatment times.

Reduced Numbers of Somatostatin Receptors in the Cerebral Cortex in Alzheimer's Disease

Science.gov (United States)

Flint Beal, M.; Mazurek, Michael F.; Tran, Vinh T.; Chattha, Geetinder; Bird, Edward D.; Martin, Joseph B.

1985-07-01

Somatostatin receptor concentrations were measured in patients with Alzheimer's disease and controls. In the frontal cortex (Brodmann areas 6, 9, and 10) and temporal cortex (Brodmann area 21), the concentrations of somatostatin in receptors in the patients were reduced to approximately 50 percent of control values. A 40 percent reduction was seen in the hippocampus, while no significant changes were found in the cingulate cortex, postcentral gyrus, temporal pole, and superior temporal gyrus. Scatchard analysis showed a reduction in receptor number rather than a change in affinity. Somatostatin-like immunoreactivity was significantly reduced in both the frontal and temporal cortex. Somatostatin-like immunoreactivity was linearly related to somatostatin-receptor binding in the cortices of Alzheimer's patients. These findings may reflect degeneration of postsynaptic neurons or cortical afferents in the patients' cerebral cortices. Alternatively, decreased somatostatinlike immunoreactivity in Alzheimer's disease might indicate increased release of somatostatin and down regulation of postsynaptic receptors.

Urotensin II modulates rapid eye movement sleep through activation of brainstem cholinergic neurons

DEFF Research Database (Denmark)

Huitron-Resendiz, Salvador; Kristensen, Morten Pilgaard; Sánchez-Alavez, Manuel

2005-01-01

administration of UII into the PPT nucleus increases REM sleep without inducing changes in the cortical blood flow. Intracerebroventricular injection of UII enhances both REM sleep and wakefulness and reduces slow-wave sleep 2. Intracerebroventricular, but not local, administration of UII increases cortical...... dorsal tegmental nuclei. This distribution suggests that the UII system is involved in functions regulated by acetylcholine, such as the sleep-wake cycle. Here, we tested the hypothesis that UII influences cholinergic PPT neuron activity and alters rapid eye movement (REM) sleep patterns in rats. Local...... synaptic transmission because it persisted in the presence of TTX and antagonists of ionotropic glutamate, GABA, and glycine receptors. Collectively, these results suggest that UII plays a role in the regulation of REM sleep independently of its cerebrovascular actions by directly activating cholinergic...

Implications of Harvest on the Boundaries of Protected Areas for Large Carnivore Viewing Opportunities.

Directory of Open Access Journals (Sweden)

Bridget L Borg

Full Text Available The desire to see free ranging large carnivores in their natural habitat is a driver of tourism in protected areas around the globe. However, large carnivores are wide-ranging and subject to human-caused mortality outside protected area boundaries. The impact of harvest (trapping or hunting on wildlife viewing opportunities has been the subject of intense debate and speculation, but quantitative analyses have been lacking. We examined the effect of legal harvest of wolves (Canis lupus along the boundaries of two North American National Parks, Denali (DNPP and Yellowstone (YNP, on wolf viewing opportunities within the parks during peak tourist season. We used data on wolf sightings, pack sizes, den site locations, and harvest adjacent to DNPP from 1997-2013 and YNP from 2008-2013 to evaluate the relationship between harvest and wolf viewing opportunities. Although sightings were largely driven by wolf population size and proximity of den sites to roads, sightings in both parks were significantly reduced by harvest. Sightings in YNP increased by 45% following years with no harvest of a wolf from a pack, and sightings in DNPP were more than twice as likely during a period with a harvest buffer zone than in years without the buffer. These findings show that harvest of wolves adjacent to protected areas can reduce sightings within those areas despite minimal impacts on the size of protected wolf populations. Consumptive use of carnivores adjacent to protected areas may therefore reduce their potential for non-consumptive use, and these tradeoffs should be considered when developing regional wildlife management policies.

Implications of Harvest on the Boundaries of Protected Areas for Large Carnivore Viewing Opportunities.

Science.gov (United States)

Borg, Bridget L; Arthur, Stephen M; Bromen, Nicholas A; Cassidy, Kira A; McIntyre, Rick; Smith, Douglas W; Prugh, Laura R

2016-01-01

The desire to see free ranging large carnivores in their natural habitat is a driver of tourism in protected areas around the globe. However, large carnivores are wide-ranging and subject to human-caused mortality outside protected area boundaries. The impact of harvest (trapping or hunting) on wildlife viewing opportunities has been the subject of intense debate and speculation, but quantitative analyses have been lacking. We examined the effect of legal harvest of wolves (Canis lupus) along the boundaries of two North American National Parks, Denali (DNPP) and Yellowstone (YNP), on wolf viewing opportunities within the parks during peak tourist season. We used data on wolf sightings, pack sizes, den site locations, and harvest adjacent to DNPP from 1997-2013 and YNP from 2008-2013 to evaluate the relationship between harvest and wolf viewing opportunities. Although sightings were largely driven by wolf population size and proximity of den sites to roads, sightings in both parks were significantly reduced by harvest. Sightings in YNP increased by 45% following years with no harvest of a wolf from a pack, and sightings in DNPP were more than twice as likely during a period with a harvest buffer zone than in years without the buffer. These findings show that harvest of wolves adjacent to protected areas can reduce sightings within those areas despite minimal impacts on the size of protected wolf populations. Consumptive use of carnivores adjacent to protected areas may therefore reduce their potential for non-consumptive use, and these tradeoffs should be considered when developing regional wildlife management policies.

Role of ghrelin in drug abuse and reward-relevant behaviors: a burgeoning field and gaps in the literature.

Science.gov (United States)

Revitsky, A R; Klein, L C

2013-09-01

Ghrelin is a gut-brain hormone that regulates energy balance through food consumption. While ghrelin is well known for its role in hypothalamic activation and homeostatic feeding, more recent evidence suggests that ghrelin also is involved in hedonic feeding through the dopaminergic reward pathway. This paper investigated how ghrelin administration (intraperitoneal, intracerebroventricular, or directly into dopaminergic reward-relevant brain regions) activates the dopaminergic reward pathway and associated reward-relevant behavioral responses in rodents. A total of 19 empirical publications that examined one or more of these variables were included in this review. Overall, ghrelin administration increases dopamine levels in the nucleus accumbens, as well as reward-relevant behaviors such as food (both standard chow and palatable foods) and alcohol consumption. Ghrelin administration also increases operant responding for sucrose, and conditioned place preference. Following a review of the small body of literature examining the effects of ghrelin administration on the dopamine reward pathway, we present a model of the relationship between ghrelin and dopaminergic reward activation. Specifically, ghrelin acts on ghrelin receptors (GHS-R1A) in the ventral tegmental area (VTA) and lateral dorsal tegmental nucleus (LDTg) to stimulate the mesolimbic dopamine reward pathway, which results in increased rewarding behaviors in rodents. Results from this review suggest that selective antagonism of the ghrelin system may serve as potential treatment for addictive drug use. This review highlights gaps in the literature, including a lack of examination of sex- or age-related differences in the effects of ghrelin on dopamine reward processes. In light of vulnerability to drug abuse among female and adolescent populations, future studies should target these individual difference factors.

Organization of the sleep-related neural systems in the brain of the river hippopotamus (Hippopotamus amphibius): A most unusual cetartiodactyl species.

Science.gov (United States)

Dell, Leigh-Anne; Patzke, Nina; Spocter, Muhammad A; Bertelsen, Mads F; Siegel, Jerome M; Manger, Paul R

2016-07-01

This study provides the first systematic analysis of the nuclear organization of the neural systems related to sleep and wake in the basal forebrain, diencephalon, midbrain, and pons of the river hippopotamus, one of the closest extant terrestrial relatives of the cetaceans. All nuclei involved in sleep regulation and control found in other mammals, including cetaceans, were present in the river hippopotamus, with no specific nuclei being absent, but novel features of the cholinergic system, including novel nuclei, were present. This qualitative similarity relates to the cholinergic, noradrenergic, serotonergic, and orexinergic systems and is extended to the γ-aminobutyric acid (GABA)ergic elements of these nuclei. Quantitative analysis reveals that the numbers of pontine cholinergic (259,578) and noradrenergic (127,752) neurons, and hypothalamic orexinergic neurons (68,398) are markedly higher than in other large-brained mammals. These features, along with novel cholinergic nuclei in the intralaminar nuclei of the dorsal thalamus and the ventral tegmental area of the midbrain, as well as a major expansion of the hypothalamic cholinergic nuclei and a large laterodorsal tegmental nucleus of the pons that has both parvocellular and magnocellular cholinergic neurons, indicates an unusual sleep phenomenology for the hippopotamus. Our observations indicate that the hippopotamus is likely to be a bihemispheric sleeper that expresses REM sleep. The novel features of the cholinergic system suggest the presence of an undescribed sleep state in the hippopotamus, as well as the possibility that this animal could, more rapidly than other mammals, switch cortical electroencephalographic activity from one state to another. J. Comp. Neurol. 524:2036-2058, 2016. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

Effectiveness of Wildlife Underpasses and Fencing to Reduce Wildlife–Vehicle Collisions

Science.gov (United States)

,; McCollister, Matthew F.

2010-01-01

Transportation planners are increasingly incorporating roadway design features to mitigate impacts of highways on wildlife and to increase driver safety. We used camera and track surveys to evaluate wildlife use before and after construction of 3 wildlife underpasses and associated fencing on a new section of United States Highway 64 in Washington County, North Carolina, USA. We recorded 242 occasions of white-tailed deer (Odocoileus virginianus) use of underpass areas before highway construction began. Following completion of the highway, we collected 2,433 photographs of 9 species with deer representing 93% of all crossings. Adjusting for differences in number of monitoring days, white-tailed deer use of underpass areas averaged 6.7 times greater after the new highway and underpasses were completed. We recorded 3,614 wildlife crossings of ≥20 species based on track counts, representing most medium and large mammals known to occur in the area and several reptiles and birds. After completion of the highway, we documented wildlife mortality due to vehicle collisions during a 13-month period and recorded 128 incidences representing ≥24 species. Within fenced highway segments, mortalities were lowest near underpasses and increased with distance from the underpasses. However, we also documented more mortalities in fenced areas compared with unfenced areas. With greater distance from an underpass, animals with smaller home ranges seemed less likely to reach the underpass and instead attempted to climb over or crawl under fencing. Based on collision reports from adjacent highway sections, the new section of United States Highway 64 experienced approximately 58% fewer wildlife mortalities (primarily white-tailed deer), suggesting underpasses and fencing reduced the number of deer–vehicle collisions. Continuous fencing between underpasses may further reduce the number of vehicle collisions for deer but additional design features (e.g., buried fencing) should be

Urban trees reduce nutrient leaching to groundwater.

Science.gov (United States)

Nidzgorski, Daniel A; Hobbie, Sarah E

2016-07-01

Many urban waterways suffer from excess nitrogen (N) and phosphorus (P), feeding algal blooms, which cause lower water clarity and oxygen levels, bad odor and taste, and the loss of desirable species. Nutrient movement from land to water is likely to be influenced by urban vegetation, but there are few empirical studies addressing this. In this study, we examined whether or not urban trees can reduce nutrient leaching to groundwater, an important nutrient export pathway that has received less attention than stormwater. We characterized leaching beneath 33 trees of 14 species, and seven open turfgrass areas, across three city parks in Saint Paul, Minnesota, USA. We installed lysimeters at 60 cm depth to collect soil water approximately biweekly from July 2011 through October 2013, except during winter and drought periods, measured dissolved organic carbon (C), N, and P in soil water, and modeled water fluxes using the BROOK90 hydrologic model. We also measured soil nutrient pools (bulk C and N, KCl-extractable inorganic N, Brays-P), tree tissue nutrient concentrations (C, N, and P of green leaves, leaf litter, and roots), and canopy size parameters (leaf biomass, leaf area index) to explore correlations with nutrient leaching. Trees had similar or lower N leaching than turfgrass in 2012 but higher N leaching in 2013; trees reduced P leaching compared with turfgrass in both 2012 and 2013, with lower leaching under deciduous than evergreen trees. Scaling up our measurements to an urban subwatershed of the Mississippi River (~17 400 ha, containing ~1.5 million trees), we estimated that trees reduced P leaching to groundwater by 533 kg in 2012 (0.031 kg/ha or 3.1 kg/km 2 ) and 1201 kg in 2013 (0.069 kg/ha or 6.9 kg/km 2 ). Removing these same amounts of P using stormwater infrastructure would cost $2.2 million and $5.0 million per year (2012 and 2013 removal amounts, respectively). © 2016 by the Ecological Society of America.

100 Area electrical distribution fault and coordination report

International Nuclear Information System (INIS)

Webber, J.J.

1994-01-01