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Sample records for medium-sized spiny neurons

  1. Developmentally coordinated extrinsic signals drive human pluripotent stem cell differentiation toward authentic DARPP-32+ medium-sized spiny neurons.

    PubMed

    Delli Carri, Alessia; Onorati, Marco; Lelos, Mariah J; Castiglioni, Valentina; Faedo, Andrea; Menon, Ramesh; Camnasio, Stefano; Vuono, Romina; Spaiardi, Paolo; Talpo, Francesca; Toselli, Mauro; Martino, Gianvito; Barker, Roger A; Dunnett, Stephen B; Biella, Gerardo; Cattaneo, Elena

    2013-01-15

    Medium-sized spiny neurons (MSNs) are the only neostriatum projection neurons, and their degeneration underlies some of the clinical features of Huntington's disease. Using knowledge of human developmental biology and exposure to key neurodevelopmental molecules, human pluripotent stem (hPS) cells were induced to differentiate into MSNs. In a feeder-free adherent culture, ventral telencephalic specification is induced by BMP/TGFβ inhibition and subsequent SHH/DKK1 treatment. The emerging FOXG1(+)/GSX2(+) telencephalic progenitors are then terminally differentiated, resulting in the systematic line-independent generation of FOXP1(+)/FOXP2(+)/CTIP2(+)/calbindin(+)/DARPP-32(+) MSNs. Similar to mature MSNs, these neurons carry dopamine and A2a receptors, elicit a typical firing pattern and show inhibitory postsynaptic currents, as well as dopamine neuromodulation and synaptic integration ability in vivo. When transplanted into the striatum of quinolinic acid-lesioned rats, hPS-derived neurons survive and differentiate into DARPP-32(+) neurons, leading to a restoration of apomorphine-induced rotation behavior. In summary, hPS cells can be efficiently driven to acquire a functional striatal fate using an ontogeny-recapitulating stepwise method that represents a platform for in vitro human developmental neurobiology studies and drug screening approaches.

  2. Three-dimensional organization of dendrites and local axon collaterals of shell and core medium-sized spiny projection neurons of the rat nucleus accumbens.

    PubMed

    van Dongen, Yvette C; Mailly, Philippe; Thierry, Anne-Marie; Groenewegen, Henk J; Deniau, Jean-Michel

    2008-09-01

    Medium-sized spiny projection neurons (MSN) in the head of the primate caudate nucleus are thought to have preferred dendritic orientations that tend to parallel the orientations of the striosomes. Moreover, recurrent axon collaterals of MSN in the rat dorsal striatum have been categorized into two types, i.e., restricted and widespread. The nucleus accumbens (Acb) has a highly complex compartmental organization, and the spatial organization of dendritic and axonal arbors of MSN has not yet been systematically studied. In this study, using single-cell juxtacellular labeling with neurobiotin as well as anterograde neuroanatomical tracing with biotinylated dextran amine, we investigated the three-dimensional (3D) organization of dendrites and axons of MSN of the rat Acb in relation to subregional (shell-core) and compartmental (patch-matrix) boundaries. Our results show that dendritic arbors of MSN in both the Acb shell and core subregions are preferentially oriented, i.e., they are flattened in at least one of the 3D-planes. The preferred orientations are influenced by shell-core and patch-matrix boundaries, suggesting parallel and independent processing of information. Dendritic orientations of MSN of the Acb core are more heterogeneous than those of the shell and the dorsal striatum, suggesting a more complex distribution of striatal inputs within the core. Although dendrites respect the shell-core and patch-matrix boundaries, recurrent axon collaterals may cross these boundaries. Finally, different degrees of overlap between dendritic and axonal arborizations of individual MSN were identified, suggesting various possibilities of lateral inhibitory interactions within and between, functionally distinct territories of the Acb.

  3. Fractional Cable Models for Spiny Neuronal Dendrites

    NASA Astrophysics Data System (ADS)

    Henry, B. I.; Langlands, T. A. M.; Wearne, S. L.

    2008-03-01

    Cable equations with fractional order temporal operators are introduced to model electrotonic properties of spiny neuronal dendrites. These equations are derived from Nernst-Planck equations with fractional order operators to model the anomalous subdiffusion that arises from trapping properties of dendritic spines. The fractional cable models predict that postsynaptic potentials propagating along dendrites with larger spine densities can arrive at the soma faster and be sustained at higher levels over longer times. Calibration and validation of the models should provide new insight into the functional implications of altered neuronal spine densities, a hallmark of normal aging and many neurodegenerative disorders.

  4. Striatal plasticity and medium spiny neuron dendritic remodeling in parkinsonism.

    PubMed

    Deutch, Ariel Y; Colbran, Roger J; Winder, Danny J

    2007-01-01

    Current approaches to Parkinson's Disease (PD) are largely based on our current understanding of the mechanisms that contribute to the death of nigrostriatal dopamine neurons. However, our understanding of the consequences of the loss of dopamine on the striatal target cells of nigrostriatal neurons is much less advanced. In particular, the compensatory changes that occur in striatal medium spiny neurons (MSNs) that have lost their normal dopamine input remains poorly understood. The compensatory changes may have either positive or negative effects. Among the alterations that occur in striatal cells of the dopamine-denervated striatum are dystrophic changes in the dendrites of MSNs, with a loss of dendritic length and dendritic spine number. Dendritic spines are the targets of convergent nigrostriatal dopamine and corticostriatal glutamate axons, and integrate these convergent signals to determine the nature of striatal output. The loss of these spines in the dopamine-denervated state may protect the MSN from overt excitotoxic death, but at the price of compromising MSN function. The loss of dendritic spines is thought be responsible for the gradual decrease in levodopa efficacy in late-stage PD, suggesting that therapeutic interventions need to be developed that target key downstream signaling complexes in medium spiny neurons.

  5. Glutamatergic Nonpyramidal Neurons From Neocortical Layer VI and Their Comparison With Pyramidal and Spiny Stellate Neurons

    PubMed Central

    Andjelic, Sofija; Gallopin, Thierry; Cauli, Bruno; Hill, Elisa L.; Roux, Lisa; Badr, Sammy; Hu, Emilie; Tamás, Gábor; Lambolez, Bertrand

    2009-01-01

    The deeper part of neocortical layer VI is dominated by nonpyramidal neurons, which lack a prominent vertically ascending dendrite and predominantly establish corticocortical connections. These neurons were studied in rat neocortical slices using patch-clamp, single-cell reverse transcription–polymerase chain reaction, and biocytin labeling. The majority of these neurons expressed the vesicular glutamate transporter but not glutamic acid decarboxylase, suggesting that a high proportion of layer VI nonpyramidal neurons are glutamatergic. Indeed, they exhibited numerous dendritic spines and established asymmetrical synapses. Our sample of glutamatergic nonpyramidal neurons displayed a wide variety of somatodendritic morphologies and a subset of these cells expressed the Nurr1 mRNA, a marker for ipsilateral, but not commissural corticocortical projection neurons in layer VI. Comparison with spiny stellate and pyramidal neurons from other layers showed that glutamatergic neurons consistently exhibited a low occurrence of GABAergic interneuron markers and regular spiking firing patterns. Analysis of electrophysiological diversity using unsupervised clustering disclosed three groups of cells. Layer V pyramidal neurons were segregated into a first group, whereas a second group consisted of a subpopulation of layer VI neurons exhibiting tonic firing. A third heterogeneous cluster comprised spiny stellate, layer II/III pyramidal, and layer VI neurons exhibiting adaptive firing. The segregation of layer VI neurons in two different clusters did not correlate either with their somatodendritic morphologies or with Nurr1 expression. Our results suggest that electrophysiological similarities between neocortical glutamatergic neurons extend beyond layer positioning, somatodendritic morphology, and projection specificity. PMID:19052106

  6. Glutamatergic nonpyramidal neurons from neocortical layer VI and their comparison with pyramidal and spiny stellate neurons.

    PubMed

    Andjelic, Sofija; Gallopin, Thierry; Cauli, Bruno; Hill, Elisa L; Roux, Lisa; Badr, Sammy; Hu, Emilie; Tamás, Gábor; Lambolez, Bertrand

    2009-02-01

    The deeper part of neocortical layer VI is dominated by nonpyramidal neurons, which lack a prominent vertically ascending dendrite and predominantly establish corticocortical connections. These neurons were studied in rat neocortical slices using patch-clamp, single-cell reverse transcription-polymerase chain reaction, and biocytin labeling. The majority of these neurons expressed the vesicular glutamate transporter but not glutamic acid decarboxylase, suggesting that a high proportion of layer VI nonpyramidal neurons are glutamatergic. Indeed, they exhibited numerous dendritic spines and established asymmetrical synapses. Our sample of glutamatergic nonpyramidal neurons displayed a wide variety of somatodendritic morphologies and a subset of these cells expressed the Nurr1 mRNA, a marker for ipsilateral, but not commissural corticocortical projection neurons in layer VI. Comparison with spiny stellate and pyramidal neurons from other layers showed that glutamatergic neurons consistently exhibited a low occurrence of GABAergic interneuron markers and regular spiking firing patterns. Analysis of electrophysiological diversity using unsupervised clustering disclosed three groups of cells. Layer V pyramidal neurons were segregated into a first group, whereas a second group consisted of a subpopulation of layer VI neurons exhibiting tonic firing. A third heterogeneous cluster comprised spiny stellate, layer II/III pyramidal, and layer VI neurons exhibiting adaptive firing. The segregation of layer VI neurons in two different clusters did not correlate either with their somatodendritic morphologies or with Nurr1 expression. Our results suggest that electrophysiological similarities between neocortical glutamatergic neurons extend beyond layer positioning, somatodendritic morphology, and projection specificity.

  7. The underside of the cerebral cortex: layer V/VI spiny inverted neurons

    PubMed Central

    Mendizabal-Zubiaga, Juan L; Reblet, Concepcion; Bueno-Lopez, Jose L

    2007-01-01

    This paper presents an account of past and current research on spiny inverted neurons – alternatively also known as ‘inverted pyramidal neurons’– in rats, rabbits and cats. In our laboratory, we have studied these cells with a battery of techniques suited for light and electron microscopy, including Nissl staining, Golgi impregnation, dye intracellular filling and axon retrograde track-tracing. Our results show that spiny inverted neurons make up less than 8.5 and 5.5% of all cortical neurons in the primary and secondary rabbit visual cortex, respectively. Infragranular spiny inverted neurons constitute 15 and 8.5% of infragranular neurons in the same animal and areas. Spiny inverted neurons congregate at layers V–VI in all studied species. Studies have also revealed that spiny inverted neurons are excitatory neurons which furnish axons for various cortico-cortical, cortico-claustral and cortico-striatal projections, but not for non-telencephalic centres such as the lateral and medial geniculate nuclei, the colliculi or the pons. As a group, each subset of inverted cells contributing to a given projection is located below the pyramidal neurons whose axons furnish the same centre. Spiny inverted neurons are particularly conspicuous as a source of the backward cortico-cortical projection to primary visual cortex and from this to the claustrum. Indeed, they constitute up to 82% of the infragranular cells that furnish these projections. Spiny inverted neurons may be classified into three subtypes according to the point of origin of the axon on the cell: the somatic basal pole which faces the cortical outer surface, the somatic flank and the reverse apical dendrite. As seen with electron microscopy, the axon initial segments of these subtypes are distinct from one another, not only in length and thickness, but also in the number of received synaptic boutons. All of these anatomical features together may support a synaptic-input integration which is peculiar to

  8. Optimal balance of the striatal medium spiny neuron network.

    PubMed

    Ponzi, Adam; Wickens, Jeffery R

    2013-04-01

    Slowly varying activity in the striatum, the main Basal Ganglia input structure, is important for the learning and execution of movement sequences. Striatal medium spiny neurons (MSNs) form cell assemblies whose population firing rates vary coherently on slow behaviourally relevant timescales. It has been shown that such activity emerges in a model of a local MSN network but only at realistic connectivities of 10 ~ 20% and only when MSN generated inhibitory post-synaptic potentials (IPSPs) are realistically sized. Here we suggest a reason for this. We investigate how MSN network generated population activity interacts with temporally varying cortical driving activity, as would occur in a behavioural task. We find that at unrealistically high connectivity a stable winners-take-all type regime is found where network activity separates into fixed stimulus dependent regularly firing and quiescent components. In this regime only a small number of population firing rate components interact with cortical stimulus variations. Around 15% connectivity a transition to a more dynamically active regime occurs where all cells constantly switch between activity and quiescence. In this low connectivity regime, MSN population components wander randomly and here too are independent of variations in cortical driving. Only in the transition regime do weak changes in cortical driving interact with many population components so that sequential cell assemblies are reproducibly activated for many hundreds of milliseconds after stimulus onset and peri-stimulus time histograms display strong stimulus and temporal specificity. We show that, remarkably, this activity is maximized at striatally realistic connectivities and IPSP sizes. Thus, we suggest the local MSN network has optimal characteristics - it is neither too stable to respond in a dynamically complex temporally extended way to cortical variations, nor is it too unstable to respond in a consistent repeatable way. Rather, it is

  9. Diversity in Long-Term Synaptic Plasticity at Inhibitory Synapses of Striatal Spiny Neurons

    ERIC Educational Resources Information Center

    Rueda-Orozco, Pavel E.; Mendoza, Ernesto; Hernandez, Ricardo; Aceves, Jose J.; Ibanez-Sandoval, Osvaldo; Galarraga, Elvira; Bargas, Jose

    2009-01-01

    Procedural memories and habits are posited to be stored in the basal ganglia, whose intrinsic circuitries possess important inhibitory connections arising from striatal spiny neurons. However, no information about long-term plasticity at these synapses is available. Therefore, this work describes a novel postsynaptically dependent long-term…

  10. Dopaminergic modulation of axon collaterals interconnecting spiny neurons of the rat striatum.

    PubMed

    Guzmán, Jaime N; Hernández, Adán; Galarraga, Elvira; Tapia, Dagoberto; Laville, Antonio; Vergara, Ramiro; Aceves, Jorge; Bargas, José

    2003-10-01

    Dopamine is a critical modulator of striatal function; its absence produces Parkinson's disease. Most cellular actions of dopamine are still unknown. This work describes the presynaptic actions of dopaminergic receptor agonists on GABAergic transmission between neostriatal projection neurons. Axon collaterals interconnect projection neurons, the main axons of which project to other basal ganglia nuclei. Most if not all of these projecting axons pass through the globus pallidus. Thus, we lesioned the intrinsic neurons of the globus pallidus and stimulated neostriatal efferent axons antidromically with a bipolar electrode located in this nucleus. This maneuver revealed a bicuculline-sensitive synaptic current while recording in spiny cells. D1 receptor agonists facilitated whereas D2 receptor agonists depressed this synaptic current. In contrast, a bicuculline-sensitive synaptic current evoked by field stimulation inside the neostriatum was not consistently modulated, in agreement with previous studies. The data are discussed in light of the most recent experimental and modeling results. The conclusion was that inhibition of spiny cells by axon collaterals of other spiny cells is quantitatively important; however, to be functionally important, this inhibition might be conditioned to the synchronized firing of spiny neurons. Finally, dopamine exerts a potentially important role regulating the extent of lateral inhibition.

  11. Somatostatinergic modulation of firing pattern and calcium-activated potassium currents in medium spiny neostriatal neurons.

    PubMed

    Galarraga, E; Vilchis, C; Tkatch, T; Salgado, H; Tecuapetla, F; Perez-Rosello, T; Perez-Garci, E; Hernandez-Echeagaray, E; Surmeier, D J; Bargas, J

    2007-05-11

    Somatostatin is synthesized and released by aspiny GABAergic interneurons of the neostriatum, some of them identified as low threshold spike generating neurons (LTS-interneurons). These neurons make synaptic contacts with spiny neostriatal projection neurons. However, very few somatostatin actions on projection neurons have been described. The present work reports that somatostatin modulates the Ca(2+) activated K(+) currents (K(Ca) currents) expressed by projection cells. These actions contribute in designing the firing pattern of the spiny projection neuron; which is the output of the neostriatum. Small conductance (SK) and large conductance (BK) K(Ca) currents represent between 30% and 50% of the sustained outward current in spiny cells. Somatostatin reduces SK-type K(+) currents and at the same time enhances BK-type K(+) currents. This dual effect enhances the fast component of the after hyperpolarizing potential while reducing the slow component. Somatostatin then modifies the firing pattern of spiny neurons which changed from a tonic regular pattern to an interrupted "stuttering"-like pattern. Semi-quantitative reverse transcriptase-polymerase chain reaction (RT-PCR) tissue expression analysis of dorsal striatal somatostatinergic receptors (SSTR) mRNA revealed that all five SSTR mRNAs are present. However, single cell RT-PCR profiling suggests that the most probable receptor in charge of this modulation is the SSTR2 receptor. Interestingly, aspiny interneurons may exhibit a "stuttering"-like firing pattern. Therefore, somatostatin actions appear to be the entrainment of projection neurons to the rhythms generated by some interneurons. Somatostatin is then capable of modifying the processing and output of the neostriatum.

  12. Populations of striatal medium spiny neurons encode vibrotactile frequency in rats: modulation by slow wave oscillations.

    PubMed

    Hawking, Thomas G; Gerdjikov, Todor V

    2013-01-01

    Dorsolateral striatum (DLS) is implicated in tactile perception and receives strong projections from somatosensory cortex. However, the sensory representations encoded by striatal projection neurons are not well understood. Here we characterized the contribution of DLS to the encoding of vibrotactile information in rats by assessing striatal responses to precise frequency stimuli delivered to a single vibrissa. We applied stimuli in a frequency range (45-90 Hz) that evokes discriminable percepts and carries most of the power of vibrissa vibration elicited by a range of complex fine textures. Both medium spiny neurons and evoked potentials showed tactile responses that were modulated by slow wave oscillations. Furthermore, medium spiny neuron population responses represented stimulus frequency on par with previously reported behavioral benchmarks. Our results suggest that striatum encodes frequency information of vibrotactile stimuli which is dynamically modulated by ongoing brain state.

  13. P2Y1 receptor modulation of Ca2+-activated K+ currents in medium-sized neurons from neonatal rat striatal slices

    PubMed Central

    Coppi, E.; Pedata, F.

    2012-01-01

    ATP signaling to neurons and glia in the nervous system occurs via activation of both P2Y and P2X receptors. Here, we investigated the effects of P2Y1 receptor stimulation in developing striatal medium-sized neurons using patch-clamp recordings from acute brain slices of 7- and 28-day-old rats. Application of the selective P2Y1 receptor agonist 2-(Methylthio) ADP trisodium salt (2-MeSADP; 250 nM) increased outward K+ currents evoked by a ramp depolarization protocol in voltage-clamp recordings. This effect was observed in 59 out of 82 cells (72%) and was blocked completely by the P2Y1 antagonist, 2′-deoxy-N6-methyl adenosine 3′,5′-diphosphate. The averaged 2-MeSADP-sensitive conductance was fitted by the sum of a linear conductance and a Boltzmann relation, giving one-half activation voltage of −14.2 mV and an equivalent charge of 2.91. The 2MeSADP-mediated effect was sensitive to submillimolar concentrations of tetraethylammonium (TEA; 200 μM), to 200 nM iberiotoxin and to 100 nM apamin, suggesting the involvement of both big and small potassium (BK and SK, respectively) calcium-activated channels. In current-clamp experiments, 2-MeSADP decreased depolarization-evoked action potential (AP) firing in all 26 cells investigated, and this effect was reversed by TEA and by apamin but not by iberiotoxin. We conclude that the stimulation of P2Y1 receptors in developing striatal neurons leads to activation of calcium-activated potassium channels [IK(Ca)] of both BK and SK subtypes, the latter responsible for decreasing the frequency of AP firing in response to current injection. Therefore, P2Y1 signaling leading to activation of IK(Ca) may be important in regulating the activity of medium-sized neurons in the striatum. PMID:22131374

  14. Behavioral and transcriptome alterations in male and female mice with postnatal deletion of TrkB in dorsal striatal medium spiny neurons

    PubMed Central

    2013-01-01

    Background The high affinity tyrosine kinase receptor, TrkB, is the primary receptor for brain derived neurotrophic factor (BDNF) and plays an important role in development, maintenance and plasticity of the striatal output medium size spiny neuron. The striatal BDNF/TrkB system is thereby implicated in many physiologic and pathophysiologic processes, the latter including mood disorders, addiction, and Huntington’s disease. We crossed a mouse harboring a transgene directing cre-recombinase expression primarily to postnatal, dorsal striatal medium spiny neurons, to a mouse containing a floxed TrkB allele (fB) mouse designed for deletion of TrkB to determine its role in the adult striatum. Results We found that there were sexually dimorphic alterations in behaviors in response to stressful situations and drugs of abuse. Significant sex and/or genotype differences were found in the forced swim test of depression-like behaviors, anxiety-like behaviors on the elevated plus maze, and cocaine conditioned reward. Microarray analysis of dorsal striatum revealed significant dysregulation in individual and groups of genes that may contribute to the observed behavioral responses and in some cases, represent previously unidentified downstream targets of TrkB. Conclusions The data point to a set of behaviors and changes in gene expression following postnatal deletion of TrkB in the dorsal striatum distinct from those in other brain regions. PMID:24369067

  15. Cytoarchitectural impairments in the medium spiny neurons of the Nucleus Accumbens core of hyperactive juvenile rats.

    PubMed

    González-Burgos, I; García-Martínez, S; Velázquez-Zamora, D A; Ponce-Rolón, R

    2010-10-01

    Dopaminergic activity in the Nucleus Accumbens has been strongly implicated in the motor hyperactivity associated with Attention deficit hyperactivity disorder. Dopaminergic and glutamatergic terminals converge on the dendritic spines of medium spiny neurons of the nucleus accumbens core, which modulate the excitatory glutamatergic activity. In this work, a Golgi study was carried out to investigate the effects of dopamine depletion on the cytoarchitecture of dendritic spines of nucleus accumbens core medium spiny neurons. The dopaminergic system of newborn male rats was lesioned intracisternally by using 6-hydroxydopamine, and subsequently, the motor activity, spine density, and the proportion of thin, stubby, mushroom, wide, branched, and double spines was compared to those in control and intact animals. Motor activity was significantly increased in the dopamine-depleted animals and while the spine density was reduced, there was no change in the proportion of the specific types of spines. Larger thin spines were observed in the dopamine-depleted animals. Indeed, dopamine depletion may lead to spine retraction due to the disregulation of spine development, and/or an increase in glutamatergic activity. The enlargement of thin spines may suggest a compensatory mechanism to increase the efficiency of synaptic inputs in response to a decrease in spines number. Together, the present findings suggest an alteration to the excitatory/inhibitory balance on dendritic spines of medium spiny neurons of the nucleus accumbens core in hyperactive juvenile rats following early dopamine depletion.

  16. Increased excitability of medium-sized dorsal root ganglion neurons by prolonged interleukin-1β exposure is K+ channel dependent and reversible

    PubMed Central

    Stemkowski, Patrick L; Noh, Myung-chul; Chen, Yishen; Smith, Peter A

    2015-01-01

    Chronic constriction injury of rat sciatic nerve promotes signs of neuropathic pain. This is associated with an increase in the level of interleukin 1β (IL-1β) in primary afferents that peaks at 7 days. This initial cytokine exposure has been proposed to trigger an enduring alteration in neuronal phenotype that underlies chronic hyper-excitability in sensory nerves, which initiates and maintains chronic neuropathic pain. We have shown previously that 5–6 days of exposure of rat dorsal root ganglia (DRGs) to 100 pm IL-1β increases the excitability of medium-sized neurons. We have now found using whole-cell recording that this increased excitability reverts to control levels within 3–4 days of cytokine removal. The effects of IL-1β were dominated by changes in K+ currents. Thus, the amplitudes of A-current, delayed rectifier and Ca2+-sensitive K+ currents were reduced by ∼68%, ∼64% and ∼36%, respectively. Effects of IL-1β on other cation currents were modest by comparison. There was thus a slight decrease in availability of high voltage-activated Ca2+ channel current, a small increase in rates of activation of hyperpolarization-activated cyclic nucleotide-gated channel current (IH), and a shift in the voltage dependence of activation of tetrodotoxin-sensitive sodium current (TTX-S INa) to more negative potentials. It is unlikely, therefore, that direct interaction of IL-1β with DRG neurons initiates an enduring phenotypic shift in their electrophysiological properties following sciatic nerve injury. Persistent increases in primary afferent excitability following nerve injury may instead depend on altered K+ channel function and on the continued presence of slightly elevated levels IL-1β and other cytokines. PMID:26110238

  17. Striatal plasticity in parkinsonism: dystrophic changes in medium spiny neurons and progression in Parkinson's disease.

    PubMed

    Deutch, A Y

    2006-01-01

    Striatal dopamine loss in Parkinson's Disease (PD) sets into play a variety of compensatory responses to help counter dopamine depletion. Most of these changes involve surviving dopamine neurons, but there are also changes in striatal medium spiny neurons (MSNs), which are the major target of dopamine axons. Among these changes are decreases in MSN dendritic length and spine density, which may dampen excessive corticostriatal glutamatergic drive onto MSNs that occurs secondary to dopamine loss. An increasing knowledge of dendritic changes in PD suggests strategies for tracking progressive worsening of symptoms and is opening new ideas on novel therapeutic strategies for PD.

  18. Muscarinic enhancement of persistent sodium current synchronizes striatal medium spiny neurons.

    PubMed

    Carrillo-Reid, Luis; Tecuapetla, Fatuel; Vautrelle, Nicolas; Hernández, Adán; Vergara, Ramiro; Galarraga, Elvira; Bargas, José

    2009-08-01

    Network dynamics denoted by synchronous firing of neuronal pools rely on synaptic interactions and intrinsic properties. In striatal medium spiny neurons, N-methyl-d-aspartate (NMDA) receptor activation endows neurons with nonlinear capabilities by inducing a negative-slope conductance region (NSCR) in the current-voltage relationship. Nonlinearities underlie associative learning, procedural memory, and the sequential organization of behavior in basal ganglia nuclei. The cholinergic system modulates the function of medium spiny projection neurons through the activation of muscarinic receptors, increasing the NMDA-induced NSCR. This enhancement is reflected as a change in the NMDA-induced network dynamics, making it more synchronous. Nevertheless, little is known about the contribution of intrinsic properties that promote this activity. To investigate the mechanisms underlying the cholinergic modulation of bistable behavior in the striatum, we used whole cell and calcium-imaging techniques. A persistent sodium current modulated by muscarinic receptor activation participated in the enhancement of the NSCR and the increased network synchrony. These experiments provide evidence that persistent sodium current generates bistable behavior in striatal neurons and contributes to the regulation of synchronous network activity. The neuromodulation of bistable properties could represent a cellular and network mechanism for cholinergic actions in the striatum.

  19. Intrinsic excitability varies by sex in prepubertal striatal medium spiny neurons

    PubMed Central

    Dorris, David M.; Cao, Jinyan; Willett, Jaime A.; Hauser, Caitlin A.

    2014-01-01

    Sex differences in neuron electrophysiological properties were traditionally associated with brain regions directly involved in reproduction in adult, postpubertal animals. There is growing acknowledgement that sex differences can exist in other developmental periods and brain regions as well. This includes the dorsal striatum (caudate/putamen), which shows robust sex differences in gene expression, neuromodulator action (including dopamine and 17β-estradiol), and relevant sensorimotor behaviors and pathologies such as the responsiveness to drugs of abuse. Here we examine whether these sex differences extend to striatal neuron electrophysiology. We test the hypothesis that passive and active medium spiny neuron (MSN) electrophysiological properties in prepubertal rat dorsal striatum differ by sex. We made whole cell recordings from male and females MSNs from acute brain slices. The slope of the evoked firing rate to current injection curve was increased in MSNs recorded from females compared with males. The initial action potential firing rate was increased in MSNs recorded from females compared with males. Action potential after-hyperpolarization peak was decreased, and threshold was hyperpolarized in MSNs recorded from females compared with males. No sex differences in passive electrophysiological properties or miniature excitatory synaptic currents were detected. These findings indicate that MSN excitability is increased in prepubertal females compared with males, providing a new mechanism that potentially contributes to generating sex differences in striatal-mediated processes. Broadly, these findings demonstrate that sex differences in neuron electrophysiological properties can exist prepuberty in brain regions not directly related to reproduction. PMID:25376786

  20. Helios expression coordinates the development of a subset of striatopallidal medium spiny neurons.

    PubMed

    Martín-Ibáñez, Raquel; Pardo, Mónica; Giralt, Albert; Miguez, Andrés; Guardia, Inés; Marion-Poll, Lucile; Herranz, Cristina; Esgleas, Miriam; Barriga, Gerardo Garcia-Díaz; Edel, Michael J; Vicario-Abejón, Carlos; Alberch, Jordi; Girault, Jean-Antoine; Chan, Susan; Kastner, Philippe; Canals, Josep M

    2017-03-13

    Here we unravel the mechanism of action of Helios (He) during the development of striatal medium spiny neurons (MSNs). He regulates the second wave of striatal neurogenesis involved in the generation of striatopallidal neurons that express dopamine 2 receptor (D2R) and enkephalin (ENK). To exert this effect He is expressed in neural progenitor cells (NPCs) retaining them into the G1/G0 phase of the cell cycle. Thus, the lack of He produces an increase of S-phase entry and S-phase length of NPCs which in turn impairs striatal neurogenesis and produces an accumulation of the number of cycling NPCs in the germinal zone (GZ) that end up dying at postnatal stages. Therefore, He(-/-) mice show a reduction in the number of Dorso-Medial Striatal MSNs in the adulthood that produces deficits in motor skills acquisition. In addition, overexpression of He in NPCs induce DARPP32 phenotype when transplanted in mouse striatum.Present findings demonstrate that He is involved in the correct development of a subset of striatopallidal MSNs and reveal new cellular mechanisms for neuronal development.

  1. Cortical regulation of dopamine depletion-induced dendritic spine loss in striatal medium spiny neurons.

    PubMed

    Neely, M D; Schmidt, D E; Deutch, A Y

    2007-10-26

    The proximate cause of Parkinson's disease is striatal dopamine depletion. Although no overt toxicity to striatal neurons has been reported in Parkinson's disease, one of the consequences of striatal dopamine loss is a decrease in the number of dendritic spines on striatal medium spiny neurons (MSNs). Dendrites of these neurons receive cortical glutamatergic inputs onto the dendritic spine head and dopaminergic inputs from the substantia nigra onto the spine neck. This synaptic arrangement suggests that dopamine gates corticostriatal glutamatergic drive onto spines. Using triple organotypic slice cultures composed of ventral mesencephalon, striatum, and cortex of the neonatal rat, we examined the role of the cortex in dopamine depletion-induced dendritic spine loss in MSNs. The striatal dopamine innervation was lesioned by treatment of the cultures with the dopaminergic neurotoxin 1-methyl-4-phenylpyridinium (MPP+) or by removing the mesencephalon. Both MPP+ and mesencephalic ablation decreased MSN dendritic spine density. Analysis of spine morphology revealed that thin spines were preferentially lost after dopamine depletion. Removal of the cortex completely prevented dopamine depletion-induced spine loss. These data indicate that the dendritic remodeling of MSNs seen in parkinsonism occurs secondary to increases in corticostriatal glutamatergic drive, and suggest that modulation of cortical activity may be a useful therapeutic strategy in Parkinson's disease.

  2. Effects of dopaminergic modulation on the integrative properties of the ventral striatal medium spiny neuron.

    PubMed

    Moyer, Jason T; Wolf, John A; Finkel, Leif H

    2007-12-01

    Dopaminergic modulation produces a variety of functional changes in the principal cell of the striatum, the medium spiny neuron (MSN). Using a 189-compartment computational model of a ventral striatal MSN, we simulated whole cell D1- and D2-receptor-mediated modulation of both intrinsic (sodium, calcium, and potassium) and synaptic currents (AMPA and NMDA). Dopamine (DA) modulations in the model were based on a review of published experiments in both ventral and dorsal striatum. To objectively assess the net effects of DA modulation, we combined reported individual channel modulations into either D1- or D2-receptor modulation conditions and studied them separately. Contrary to previous suggestions, we found that D1 modulation had no effect on MSN nonlinearity and could not induce bistability. In agreement with previous suggestions, we found that dopaminergic modulation leads to changes in input filtering and neuronal excitability. Importantly, the changes in neuronal excitability agree with the classical model of basal ganglia function. We also found that DA modulation can alter the integration time window of the MSN. Interestingly, the effects of DA modulation of synaptic properties opposed the effects of DA modulation of intrinsic properties, with the synaptic modulations generally dominating the net effect. We interpret this lack of synergy to suggest that the regulation of whole cell integrative properties is not the primary functional purpose of DA. We suggest that D1 modulation might instead primarily regulate calcium influx to dendritic spines through NMDA and L-type calcium channels, by both direct and indirect mechanisms.

  3. Dysfunction of ventrolateral striatal dopamine receptor type 2-expressing medium spiny neurons impairs instrumental motivation

    PubMed Central

    Tsutsui-Kimura, Iku; Takiue, Hiroyuki; Yoshida, Keitaro; Xu, Ming; Yano, Ryutaro; Ohta, Hiroyuki; Nishida, Hiroshi; Bouchekioua, Youcef; Okano, Hideyuki; Uchigashima, Motokazu; Watanabe, Masahiko; Takata, Norio; Drew, Michael R.; Sano, Hiromi; Mimura, Masaru; Tanaka, Kenji F.

    2017-01-01

    Impaired motivation is present in a variety of neurological disorders, suggesting that decreased motivation is caused by broad dysfunction of the nervous system across a variety of circuits. Based on evidence that impaired motivation is a major symptom in the early stages of Huntington's disease, when dopamine receptor type 2-expressing striatal medium spiny neurons (D2-MSNs) are particularly affected, we hypothesize that degeneration of these neurons would be a key node regulating motivational status. Using a progressive, time-controllable, diphtheria toxin-mediated cell ablation/dysfunction technique, we find that loss-of-function of D2-MSNs within ventrolateral striatum (VLS) is sufficient to reduce goal-directed behaviours without impairing reward preference or spontaneous behaviour. Moreover, optogenetic inhibition and ablation of VLS D2-MSNs causes, respectively, transient and chronic reductions of goal-directed behaviours. Our data demonstrate that the circuitry containing VLS D2-MSNs control motivated behaviours and that VLS D2-MSN loss-of-function is a possible cause of motivation deficits in neurodegenerative diseases. PMID:28145402

  4. Dopamine-deprived striatal GABAergic interneurons burst and generate repetitive gigantic IPSCs in medium spiny neurons.

    PubMed

    Dehorter, Nathalie; Guigoni, Celine; Lopez, Catherine; Hirsch, June; Eusebio, Alexandre; Ben-Ari, Yehezkel; Hammond, Constance

    2009-06-17

    Striatal GABAergic microcircuits modulate cortical responses and movement execution in part by controlling the activity of medium spiny neurons (MSNs). How this is altered by chronic dopamine depletion, such as in Parkinson's disease, is not presently understood. We now report that, in dopamine-depleted slices of the striatum, MSNs generate giant spontaneous postsynaptic GABAergic currents (single or in bursts at 60 Hz) interspersed with silent episodes, rather than the continuous, low-frequency GABAergic drive (5 Hz) observed in control MSNs. This shift was observed in one-half of the MSN population, including both "D(1)-negative" and "D(1)-positive" MSNs. Single GABA and NMDA channel recordings revealed that the resting membrane potential and reversal potential of GABA were similar in control and dopamine-depleted MSNs, and depolarizing, but not excitatory, actions of GABA were observed. Glutamatergic and cholinergic antagonists did not block the GABAergic oscillations, suggesting that they were generated by GABAergic neurons. In support of this, cell-attached recordings revealed that a subpopulation of intrastriatal GABAergic interneurons generated bursts of spikes in dopamine-deprived conditions. This subpopulation included low-threshold spike interneurons but not fast-spiking interneurons, cholinergic interneurons, or MSNs. Therefore, a population of local GABAergic interneurons shifts from tonic to oscillatory mode when dopamine deprived and gives rise to spontaneous repetitive giant GABAergic currents in one-half the MSNs. We suggest that this may in turn alter integration of cortical signals by MSNs.

  5. Developmental Alterations in Motor Coordination and Medium Spiny Neuron Markers in Mice Lacking PGC-1α

    PubMed Central

    Lucas, Elizabeth K.; Dougherty, Sarah E.; McMeekin, Laura J.; Trinh, Alisa T.; Reid, Courtney S.; Cowell, Rita M.

    2012-01-01

    Accumulating evidence implicates the transcriptional coactivator peroxisome proliferator activated receptor γ coactivator 1α (PGC-1α) in the pathophysiology of Huntington Disease (HD). Adult PGC-1α −/− mice exhibit striatal neurodegeneration, and reductions in the expression of PGC-1α have been observed in striatum and muscle of HD patients as well as in animal models of the disease. However, it is unknown whether decreased expression of PGC-1α alone is sufficient to lead to the motor phenotype and striatal pathology characteristic of HD. For the first time, we show that young PGC-1α −/− mice exhibit severe rotarod deficits, decreased rearing behavior, and increased occurrence of tremor in addition to the previously described hindlimb clasping. Motor impairment and striatal vacuolation are apparent in PGC-1α −/− mice by four weeks of age and do not improve or decline by twelve weeks of age. The behavioral and pathological phenotype of PGC-1α −/− mice can be completely recapitulated by conditional nervous system deletion of PGC-1α, indicating that peripheral effects are not responsible for the observed abnormalities. Evaluation of the transcriptional profile of PGC-1α −/− striatal neuron populations and comparison to striatal neuron profiles of R6/2 HD mice revealed that PGC-1α deficiency alone is not sufficient to cause the transcriptional changes observed in this HD mouse model. In contrast to R6/2 HD mice, PGC-1α −/− mice show increases in the expression of medium spiny neuron (MSN) markers with age, suggesting that the observed behavioral and structural abnormalities are not primarily due to MSN loss, the defining pathological feature of HD. These results indicate that PGC-1α is required for the proper development of motor circuitry and transcriptional homeostasis in MSNs and that developmental disruption of PGC-1α leads to long-term alterations in motor functioning. PMID:22916173

  6. Different Corticostriatal Integration in Spiny Projection Neurons from Direct and Indirect Pathways

    PubMed Central

    Flores-Barrera, Edén; Vizcarra-Chacón, Bianca J.; Tapia, Dagoberto; Bargas, José; Galarraga, Elvira

    2010-01-01

    The striatum is the principal input structure of the basal ganglia. Major glutamatergic afferents to the striatum come from the cerebral cortex and make monosynaptic contacts with medium spiny projection neurons (MSNs) and interneurons. Also: glutamatergic afferents to the striatum come from the thalamus. Despite differences in axonal projections, dopamine (DA) receptors expression and differences in excitability between MSNs from “direct” and “indirect” basal ganglia pathways, these neuronal classes have been thought as electrophysiologically very similar. Based on work with bacterial artificial chromosome (BAC) transgenic mice, here it is shown that corticostriatal responses in D1- and D2-receptor expressing MSNs (D1- and D2-MSNs) are radically different so as to establish an electrophysiological footprint that readily differentiates between them. Experiments in BAC mice allowed us to predict, with high probability (P > 0.9), in rats or non-BAC mice, whether a recorded neuron, from rat or mouse, was going to be substance P or enkephalin (ENK) immunoreactive. Responses are more prolonged and evoke more action potentials in D1-MSNs, while they are briefer and exhibit intrinsic autoregenerative responses in D2-MSNs. A main cause for these differences was the interaction of intrinsic properties with the inhibitory contribution in each response. Inhibition always depressed corticostriatal depolarization in D2-MSNs, while it helped in sustaining prolonged depolarizations in D1-MSNs, in spite of depressing early discharge. Corticostriatal responses changed dramatically after striatal DA depletion in 6-hydroxy-dopamine (6-OHDA) lesioned animals: a response reduction was seen in substance P (SP)+ MSNs whereas an enhanced response was seen in ENK+ MSNs. The end result was that differences in the responses were greatly diminished after DA depletion. PMID:20589098

  7. GABAA receptor activity shapes the formation of inhibitory synapses between developing medium spiny neurons

    PubMed Central

    Arama, Jessica; Abitbol, Karine; Goffin, Darren; Fuchs, Celine; Sihra, Talvinder S.; Thomson, Alex M.; Jovanovic, Jasmina N.

    2015-01-01

    Basal ganglia play an essential role in motor coordination and cognitive functions. The GABAergic medium spiny neurons (MSNs) account for ~95% of all the neurons in this brain region. Central to the normal functioning of MSNs is integration of synaptic activity arriving from the glutamatergic corticostriatal and thalamostriatal afferents, with synaptic inhibition mediated by local interneurons and MSN axon collaterals. In this study we have investigated how the specific types of GABAergic synapses between the MSNs develop over time, and how the activity of GABAA receptors (GABAARs) influences this development. Isolated embryonic (E17) MSNs form a homogenous population in vitro and display spontaneous synaptic activity and functional properties similar to their in vivo counterparts. In dual whole-cell recordings of synaptically connected pairs of MSNs, action potential (AP)-activated synaptic events were detected between 7 and 14 days in vitro (DIV), which coincided with the shift in GABAAR operation from depolarization to hyperpolarization, as detected indirectly by intracellular calcium imaging. In parallel, the predominant subtypes of inhibitory synapses, which innervate dendrites of MSNs and contain GABAAR α1 or α2 subunits, underwent distinct changes in the size of postsynaptic clusters, with α1 becoming smaller and α2 larger over time, while both the percentage and the size of mixed α1/α2-postsynaptic clusters were increased. When activity of GABAARs was under chronic blockade between 4–7 DIV, the structural properties of these synapses remained unchanged. In contrast, chronic inhibition of GABAARs between 7–14 DIV led to reduction in size of α1- and α1/α2-postsynaptic clusters and a concomitant increase in number and size of α2-postsynaptic clusters. Thus, the main subtypes of GABAergic synapses formed by MSNs are regulated by GABAAR activity, but in opposite directions, and thus appear to be driven by different molecular mechanisms. PMID

  8. New Rules Governing Synaptic Plasticity In Core Nucleus Accumbens Medium Spiny Neurons

    PubMed Central

    Ji, Xincai; Martin, Gilles E.

    2012-01-01

    The nucleus accumbens is a forebrain region responsible for drug reward and goal directed behaviors. It has long been believed that drugs of abuse exert their addictive properties on behavior by altering the strength of synaptic communication over long periods of time. To date, attempts at understanding the relationship between drugs of abuse and synaptic plasticity have relied on the high-frequency long-term potentiation model of Bliss and LØmo (1973). We examined synaptic plasticity using spike-timing-dependent plasticity, a stimulation paradigm that reflects more closely in vivo firing patterns of core NAcc medium spiny neurons and their afferents. In contrast to other brain regions, the same stimulation paradigm evoked bidirectional long-term plasticity. Long-term potentiation (tLTP) magnitude changed with delay between action potentials (APs) and excitatory post-synaptic potentials (EPSPs), and frequency, while that of long-term depression (tLTD) remained unchanged. We showed that tLTP depended on NMDA receptors, whereas tLTD relied on action potentials. Importantly, intracellular calcium signaling pathways mobilized during tLTP and tLTD were different. Thus, calcium-induced calcium release underlies tLTD but not tLTP. Finally, we found that the firing pattern of a subset of MSNs was strongly inhibited by dopamine receptor agonists. Surprisingly, these neurons were exclusively associated with tLTP but not with tLTD. Taken together, these data point to the existence of two subgroups of MSNs with distinct properties, each displaying unique abilities to undergo synaptic plasticity. PMID:23013293

  9. Genetic Inhibition of CaMKII in Dorsal Striatal Medium Spiny Neurons Reduces Functional Excitatory Synapses and Enhances Intrinsic Excitability

    PubMed Central

    Klug, Jason R.; Mathur, Brian N.; Kash, Thomas L.; Wang, Hui-Dong; Matthews, Robert T.; Robison, A. J.; Anderson, Mark E.; Deutch, Ariel Y.; Lovinger, David M.; Colbran, Roger J.; Winder, Danny G.

    2012-01-01

    Ca2+/calmodulin-dependent protein kinase II (CaMKII) is abundant in striatal medium spiny neurons (MSNs). CaMKII is dynamically regulated by changes in dopamine signaling, as occurs in Parkinson's disease as well as addiction. Although CaMKII has been extensively studied in the hippocampus where it regulates excitatory synaptic transmission, relatively little is known about how it modulates neuronal function in the striatum. Therefore, we examined the impact of selectively overexpressing an EGFP-fused CaMKII inhibitory peptide (EAC3I) in striatal medium spiny neurons (MSNs) using a novel transgenic mouse model. EAC3I-expressing cells exhibited markedly decreased excitatory transmission, indicated by a decrease in the frequency of spontaneous excitatory postsynaptic currents (sEPSCs). This decrease was not accompanied by changes in the probability of release, levels of glutamate at the synapse, or changes in dendritic spine density. CaMKII regulation of the AMPA receptor subunit GluA1 is a major means by which the kinase regulates neuronal function in the hippocampus. We found that the decrease in striatal excitatory transmission seen in the EAC3I mice is mimicked by deletion of GluA1. Further, while CaMKII inhibition decreased excitatory transmission onto MSNs, it increased their intrinsic excitability. These data suggest that CaMKII plays a critical role in setting the excitability rheostat of striatal MSNs by coordinating excitatory synaptic drive and the resulting depolarization response. PMID:23028932

  10. Genetic inhibition of CaMKII in dorsal striatal medium spiny neurons reduces functional excitatory synapses and enhances intrinsic excitability.

    PubMed

    Klug, Jason R; Mathur, Brian N; Kash, Thomas L; Wang, Hui-Dong; Matthews, Robert T; Robison, A J; Anderson, Mark E; Deutch, Ariel Y; Lovinger, David M; Colbran, Roger J; Winder, Danny G

    2012-01-01

    Ca(2+)/calmodulin-dependent protein kinase II (CaMKII) is abundant in striatal medium spiny neurons (MSNs). CaMKII is dynamically regulated by changes in dopamine signaling, as occurs in Parkinson's disease as well as addiction. Although CaMKII has been extensively studied in the hippocampus where it regulates excitatory synaptic transmission, relatively little is known about how it modulates neuronal function in the striatum. Therefore, we examined the impact of selectively overexpressing an EGFP-fused CaMKII inhibitory peptide (EAC3I) in striatal medium spiny neurons (MSNs) using a novel transgenic mouse model. EAC3I-expressing cells exhibited markedly decreased excitatory transmission, indicated by a decrease in the frequency of spontaneous excitatory postsynaptic currents (sEPSCs). This decrease was not accompanied by changes in the probability of release, levels of glutamate at the synapse, or changes in dendritic spine density. CaMKII regulation of the AMPA receptor subunit GluA1 is a major means by which the kinase regulates neuronal function in the hippocampus. We found that the decrease in striatal excitatory transmission seen in the EAC3I mice is mimicked by deletion of GluA1. Further, while CaMKII inhibition decreased excitatory transmission onto MSNs, it increased their intrinsic excitability. These data suggest that CaMKII plays a critical role in setting the excitability rheostat of striatal MSNs by coordinating excitatory synaptic drive and the resulting depolarization response.

  11. Marked differences in the number and type of synapses innervating the somata and primary dendrites of midbrain dopaminergic neurons, striatal cholinergic interneurons, and striatal spiny projection neurons in the rat.

    PubMed

    Sizemore, Rachel J; Zhang, Rong; Lin, Naili; Goddard, Liping; Wastney, Timothy; Parr-Brownlie, Louise C; Reynolds, John N J; Oorschot, Dorothy E

    2016-04-01

    Elucidating the link between cellular activity and goal-directed behavior requires a fuller understanding of the mechanisms underlying burst firing in midbrain dopaminergic neurons and those that suppress activity during aversive or non-rewarding events. We have characterized the afferent synaptic connections onto these neurons in the rat substantia nigra pars compacta (SNpc) and ventral tegmental area (VTA), and compared these findings with cholinergic interneurons and spiny projection neurons in the striatum. We found that the average absolute number of synapses was three to three and one-half times greater onto the somata of dorsal striatal spiny projection neurons than onto the somata of dopaminergic neurons in the SNpc or dorsal striatal cholinergic interneurons. A similar comparison between populations of dopamine neurons revealed a two times greater number of somatic synapses on VTA dopaminergic neurons than SNpc dopaminergic neurons. The percentage of symmetrical, presumably inhibitory, synaptic inputs on somata was significantly higher on spiny projection neurons and cholinergic interneurons compared with SNpc dopaminergic neurons. Synaptic data on the primary dendrites yielded similar significant differences for the percentage of symmetrical synapses for VTA dopaminergic vs. striatal neurons. No differences in the absolute number or type of somatic synapses were evident for dopaminergic neurons in the SNpc of Wistar vs. Sprague-Dawley rat strains. These data from identified neurons are pivotal for interpreting their electrophysiological responses to afferent activity and for generating realistic computer models of neuronal networks of striatal and midbrain dopaminergic function.

  12. Integration of Biochemical and Electrical Signaling-Multiscale Model of the Medium Spiny Neuron of the Striatum

    PubMed Central

    Mattioni, Michele; Le Novère, Nicolas

    2013-01-01

    Neuron behavior results from the interplay between networks of biochemical processes and electrical signaling. Synaptic plasticity is one of the neuronal properties emerging from such an interaction. One of the current approaches to study plasticity is to model either its electrical aspects or its biochemical components. Among the chief reasons are the different time scales involved, electrical events happening in milliseconds while biochemical cascades respond in minutes or hours. In order to create multiscale models taking in consideration both aspects simultaneously, one needs to synchronize the two models, and exchange relevant variable values. We present a new event-driven algorithm to synchronize different neuronal models, which decreases computational time and avoids superfluous synchronizations. The algorithm is implemented in the TimeScales framework. We demonstrate its use by simulating a new multiscale model of the Medium Spiny Neuron of the Neostriatum. The model comprises over a thousand dendritic spines, where the electrical model interacts with the respective instances of a biochemical model. Our results show that a multiscale model is able to exhibit changes of synaptic plasticity as a result of the interaction between electrical and biochemical signaling. Our synchronization strategy is general enough to be used in simulations of other models with similar synchronization issues, such as networks of neurons. Moreover, the integration between the electrical and the biochemical models opens up the possibility to investigate multiscale process, like synaptic plasticity, in a more global manner, while taking into account a more realistic description of the underlying mechanisms. PMID:23843966

  13. Lack of GPR88 enhances medium spiny neuron activity and alters motor- and cue-dependent behaviors.

    PubMed

    Quintana, Albert; Sanz, Elisenda; Wang, Wengang; Storey, Granville P; Güler, Ali D; Wanat, Matthew J; Roller, Bryan A; La Torre, Anna; Amieux, Paul S; McKnight, G Stanley; Bamford, Nigel S; Palmiter, Richard D

    2012-11-01

    The striatum regulates motor control, reward and learning. Abnormal function of striatal GABAergic medium spiny neurons (MSNs) is believed to contribute to the deficits in these processes that are observed in many neuropsychiatric diseases. The orphan G protein-coupled receptor GPR88 is robustly expressed in MSNs and is regulated by neuropharmacological drugs, but its contribution to MSN physiology and behavior is unclear. We found that, in the absence of GPR88, MSNs showed increased glutamatergic excitation and reduced GABAergic inhibition, which promoted enhanced firing rates in vivo, resulting in hyperactivity, poor motor coordination and impaired cue-based learning in mice. Targeted viral expression of GPR88 in MSNs rescued the molecular and electrophysiological properties and normalized behavior, suggesting that aberrant MSN activation in the absence of GPR88 underlies behavioral deficits and its dysfunction may contribute to behaviors observed in neuropsychiatric disease.

  14. Phenotype-dependent inhibition of glutamatergic transmission on nucleus accumbens medium spiny neurons by the abused inhalant toluene.

    PubMed

    Beckley, Jacob T; Randall, Patrick K; Smith, Rachel J; Hughes, Benjamin A; Kalivas, Peter W; Woodward, John J

    2016-05-01

    Abused inhalants are voluntarily inhaled at high concentrations to produce intoxicating effects. Results from animal studies show that the abused inhalant toluene triggers behaviors, such as self-administration and conditioned place preference, which are commonly associated with addictive drugs. However, little is known about how toluene affects neurons within the nucleus accumbens (NAc), a brain region within the basal ganglia that mediates goal-directed behaviors and is implicated in the development and maintenance of addictive behaviors. Here we report that toluene inhibits a component of the after-hyperpolarization potential, and dose-dependently inhibits N-methyl-D-aspartate (NMDA)-mediated currents in rat NAc medium spiny neurons (MSN). Moreover, using the multivariate statistical technique, partial least squares discriminative analysis to analyze electrophysiological measures from rat NAc MSNs, we show that toluene induces a persistent depression of α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA)-mediated currents in one subtype of NAc MSNs, and that the electrophysiological features of MSN neurons predicts their sensitivity to toluene. The CB1 receptor antagonist AM281 blocked the toluene-induced long-term depression of AMPA currents, indicating that this process is dependent on endocannabinoid signaling. The neuronal identity of recorded cells was examined using dual histochemistry and shows that toluene-sensitive NAc neurons are dopamine D2 MSNs that express preproenkephalin mRNA. Overall, the results from these studies indicate that physiological characteristics obtained from NAc MSNs during whole-cell patch-clamp recordings reliably predict neuronal phenotype, and that the abused inhalant toluene differentially depresses excitatory neurotransmission in NAc neuronal subtypes.

  15. BDNF contributes to both rapid and homeostatic alterations in AMPA receptor surface expression in nucleus accumbens medium spiny neurons

    PubMed Central

    Reimers, Jeremy M.; Loweth, Jessica A.; Wolf, Marina E.

    2015-01-01

    Brain-derived neurotrophic factor (BDNF) plays a critical role in plasticity at glutamate synapses and the effects of repeated cocaine exposure. We recently showed that intracranial injection of BDNF into the rat nucleus accumbens (NAc), a key region for cocaine addiction, rapidly increases AMPA receptor (AMPAR) surface expression. To further characterize BDNF’s role in both rapid AMPAR trafficking and slower, homeostatic changes in AMPAR surface expression, we investigated the effects of acute (30 min) and long-term (24 h) treatment with BDNF on AMPAR distribution in NAc medium spiny neurons from postnatal rats co-cultured with mouse prefrontal cortex (PFC) neurons to restore excitatory inputs. Immunocytochemical studies showed that acute BDNF treatment increased cell surface GluA1 and GluA2 levels, as well as their co-localization, on NAc neurons. This effect of BDNF, confirmed using a protein crosslinking assay, was dependent on ERK but not AKT signaling. In contrast, long-term BDNF treatment decreased AMPAR surface expression on NAc neurons. Based on this latter result, we tested the hypothesis that BDNF plays a role in AMPAR “scaling down” in response to a prolonged increase in neuronal activity produced by bicuculline (24 h). Supporting this hypothesis, decreasing BDNF signaling with the extracellular BDNF scavenger TrkB-Fc prevented the scaling down of GluA1 and GluA2 surface levels in NAc neurons normally produced by bicuculline. In conclusion, BDNF exerts bidirectional effects on NAc AMPAR surface expression, depending on duration of exposure. Furthermore, BDNF’s involvement in synaptic scaling in the NAc differs from its previously described role in the visual cortex. PMID:24712995

  16. Extracerebellar role for Cerebellin1: modulation of dendritic spine density and synapses in striatal medium spiny neurons.

    PubMed

    Kusnoor, S V; Parris, J; Muly, E C; Morgan, J I; Deutch, A Y

    2010-07-01

    Cerebellin1 (Cbln1) is a secreted glycoprotein that was originally isolated from the cerebellum and subsequently found to regulate synaptic development and stability. Cbln1 has a heterogeneous distribution in brain, but the only site in which it has been shown to have central effects is the cerebellar cortex, where loss of Cbln1 causes a reduction in granule cell-Purkinje cell synapses. Neurons of the thalamic parafascicular nucleus (PF), which provide glutamatergic projections to the striatum, also express high levels of Cbln1. We first examined Cbln1 in thalamostriatal neurons and then determined if cbln1 knockout mice exhibit structural deficits in striatal neurons. Virtually all PF neurons express Cbln1-immunoreactivity (-ir). In contrast, only rare Cbln1-ir neurons are present in the central medial complex, the other thalamic region that projects heavily to the dorsal striatum. In the striatum Cbln1-ir processes are apposed to medium spiny neuron (MSN) dendrites; ultrastructural studies revealed that Cbln1-ir axon terminals form axodendritic synapses with MSNs. Tract-tracing studies found that all PF cells retrogradely labeled from the striatum express Cbln1-ir. We then examined the dendritic structure of Golgi-impregnated MSNs in adult cbln1 knockout mice. MSN dendritic spine density was markedly increased in cbln1(-/-) mice relative to wildtype littermates, but total dendritic length was unchanged. Ultrastructural examination revealed an increase in the density of MSN axospinous synapses in cbln1(-/-) mice, with no change in postsynaptic density length. Thus, Cbln1 determines the dendritic structure of striatal MSNs, with effects distinct from those seen in the cerebellum.

  17. MPTP Neurotoxicity and Testosterone Induce Dendritic Remodeling of Striatal Medium Spiny Neurons in the C57Bl/6 Mouse

    PubMed Central

    Antzoulatos, Eleni; Jakowec, Michael W.; Petzinger, Giselle M.; Wood, Ruth I.

    2011-01-01

    Nigrostriatal damage is increased in males relative to females. While estrogen is neuroprotective in females, less is known about potential protective effects of testosterone in males. We determined if castration enhances neuronal injury to 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP). Castrates or sham-castrated mice were sacrificed 1 week following injection of MPTP (4 × 20 mg/kg) or saline (n = 11-12/group). The right striatum was immunostained for tyrosine hydroxylase (TH). The left hemisphere was stained by Golgi Cox to quantify neuronal morphology in medium spiny neurons (MSNs) of the dorsolateral striatum. MPTP reduced TH, but there was no effect of castration and no interaction. For MSN dendritic morphology, MPTP decreased the highest branch order and increased spine density on 2nd-order dendrites. Castrated males had shorter 5th-order dendrites. However, there was no interaction between gonadal status and MPTP. Thus, castration and MPTP exert nonoverlapping effects on MSN morphology with castration acting on distal dendrites and MPTP acting proximally. PMID:21765998

  18. Effects of morphine withdrawal on the membrane properties of medium spiny neurons in the nucleus accumbens shell.

    PubMed

    Wu, Xiaobo; Shi, Meimei; Ling, Hengli; Wei, Chunling; Liu, Yihui; Liu, Zhiqiang; Ren, Wei

    2013-01-01

    Medium spiny neurons (MSNs) in the nucleus accumbens (NAc) undergo persistent alterations in their biological and physiological characteristics upon exposure to drugs of abuse. Previous studies demonstrated that the biochemical, morphological, and intrinsic physiological properties of MSNs are heterogeneous and provided new insights into the physiological and molecular roles of individual MSNs in addictive behaviors. However, it remains unclear whether MSNs in the NAc shell (NAcSh), an important region for mediating behavioral sensitization, are electrophysiologically heterogeneous and how such heterogeneity is relevant to neuroadaptation associated with drug addiction. Here, the membrane properties, i.e., the intrinsic excitability and spike adaptation, of MSNs in the NAcSh from saline- or morphine-treated rats were investigated in vitro by whole-cell recording. In saline-treated rats, three distinct cell types were identified by their membrane properties: type I neurons showed high levels of intrinsic excitability and rapid spike adaptation; type II neurons showed moderate levels of intrinsic excitability and relatively slow spike frequency adaptation; type III neurons showed low levels of intrinsic excitability and putative strong spike adaptation. MSNs in rats undergoing withdrawal from chronic morphine treatment (10-14 days after the last injection) also exhibited the typical firing behaviors of these three types of neurons. However, the membrane properties of the MSNs were differentially altered after withdrawal. There was an enhancement in intrinsic excitability in type II MSNs and a promotion of spike adaptation in type I MSNs. The apamin-sensitive afterhyperpolarization current (I(AHP)) and the apamin-insensitive I(AHP) of the NAcSh MSNs were attenuated after chronic morphine withdrawal. These findings suggest that individual MSNs in the NAcSh manifest unique electrophysiological properties, which might contribute to psychostimulant-induced neuroadaptation.

  19. Mushroom spine dynamics in medium spiny neurons of dorsal striatum associated with memory of moderate and intense training.

    PubMed

    Bello-Medina, Paola C; Flores, Gonzalo; Quirarte, Gina L; McGaugh, James L; Prado Alcalá, Roberto A

    2016-10-18

    A growing body of evidence indicates that treatments that typically impair memory consolidation become ineffective when animals are given intense training. This effect has been obtained by treatments interfering with the neural activity of several brain structures, including the dorsal striatum. The mechanisms that mediate this phenomenon are unknown. One possibility is that intense training promotes the transfer of information derived from the enhanced training to a wider neuronal network. We now report that inhibitory avoidance (IA) induces mushroom spinogenesis in the medium spiny neurons (MSNs) of the dorsal striatum in rats, which is dependent upon the intensity of the foot-shock used for training; that is, the effect is seen only when high-intensity foot-shock is used in training. We also found that the relative density of thin spines was reduced. These changes were evident at 6 h after training and persisted for at least 24 h afterward. Importantly, foot-shock alone did not increase spinogenesis. Spine density in MSNs in the accumbens was also increased, but the increase did not correlate with the associative process involved in IA; rather, it resulted from the administration of the aversive stimulation alone. These findings suggest that mushroom spines of MSNs of the dorsal striatum receive afferent information that is involved in the integrative activity necessary for memory consolidation, and that intense training facilitates transfer of information from the dorsal striatum to other brain regions through augmented spinogenesis.

  20. Cocaine and Amphetamine Induce Overlapping but Distinct Patterns of AMPAR Plasticity in Nucleus Accumbens Medium Spiny Neurons

    PubMed Central

    Jedynak, Jakub; Hearing, Matthew; Ingebretson, Anna; Ebner, Stephanie R; Kelly, Matthew; Fischer, Rachel A; Kourrich, Saïd; Thomas, Mark J

    2016-01-01

    Repeated exposure to psychostimulant drugs such as cocaine or amphetamine can promote drug-seeking and -taking behavior. In rodent addiction models, persistent changes in excitatory glutamatergic neurotransmission in the nucleus accumbens (NAc) appear to drive this drug-induced behavioral plasticity. To study whether changes in glutamatergic signaling are shared between or exclusive to specific psychostimulant drugs, we examined synaptic transmission from mice following repeated amphetamine or cocaine administration. Synaptic transmission mediated by AMPA-type glutamate receptors was potentiated in the NAc shell 10–14 days following repeated amphetamine or cocaine treatment. This synaptic enhancement was depotentiated by re-exposure to amphetamine or cocaine. By contrast, in the NAc core only repeated cocaine exposure enhanced synaptic transmission, which was subsequently depotentiated by an additional cocaine but not amphetamine injection during drug abstinence. To better understand the drug-induced depotentiation, we replicated these in vivo findings using an ex vivo model termed ‘challenge in the bath,' and showed that drug-induced decreases in synaptic strength occur rapidly (within 30 min) and require activation of metabotropic glutamate receptor 5 (mGluR5) and protein synthesis in the NAc shell, but not NAc core. Overall, these data demonstrate the specificity of neuronal circuit changes induced by amphetamine, introduce a novel method for studying drug challenge-induced plasticity, and define NAc shell medium spiny neurons as a primary site of persistent AMPA-type glutamate receptor plasticity by two widely used psychostimulant drugs. PMID:26068728

  1. Cocaine and Amphetamine Induce Overlapping but Distinct Patterns of AMPAR Plasticity in Nucleus Accumbens Medium Spiny Neurons.

    PubMed

    Jedynak, Jakub; Hearing, Matthew; Ingebretson, Anna; Ebner, Stephanie R; Kelly, Matthew; Fischer, Rachel A; Kourrich, Saïd; Thomas, Mark J

    2016-01-01

    Repeated exposure to psychostimulant drugs such as cocaine or amphetamine can promote drug-seeking and -taking behavior. In rodent addiction models, persistent changes in excitatory glutamatergic neurotransmission in the nucleus accumbens (NAc) appear to drive this drug-induced behavioral plasticity. To study whether changes in glutamatergic signaling are shared between or exclusive to specific psychostimulant drugs, we examined synaptic transmission from mice following repeated amphetamine or cocaine administration. Synaptic transmission mediated by AMPA-type glutamate receptors was potentiated in the NAc shell 10-14 days following repeated amphetamine or cocaine treatment. This synaptic enhancement was depotentiated by re-exposure to amphetamine or cocaine. By contrast, in the NAc core only repeated cocaine exposure enhanced synaptic transmission, which was subsequently depotentiated by an additional cocaine but not amphetamine injection during drug abstinence. To better understand the drug-induced depotentiation, we replicated these in vivo findings using an ex vivo model termed 'challenge in the bath,' and showed that drug-induced decreases in synaptic strength occur rapidly (within 30 min) and require activation of metabotropic glutamate receptor 5 (mGluR5) and protein synthesis in the NAc shell, but not NAc core. Overall, these data demonstrate the specificity of neuronal circuit changes induced by amphetamine, introduce a novel method for studying drug challenge-induced plasticity, and define NAc shell medium spiny neurons as a primary site of persistent AMPA-type glutamate receptor plasticity by two widely used psychostimulant drugs.

  2. The Sodium Channel β4 Auxiliary Subunit Selectively Controls Long-Term Depression in Core Nucleus Accumbens Medium Spiny Neurons

    PubMed Central

    Ji, Xincai; Saha, Sucharita; Gao, Guangping; Lasek, Amy W.; Homanics, Gregg E.; Guildford, Melissa; Tapper, Andrew R.; Martin, Gilles E.

    2017-01-01

    Voltage-gated sodium channels are essential for generating the initial rapid depolarization of neuronal membrane potential during action potentials (APs) that enable cell-to-cell communication, the propagation of signals throughout the brain, and the induction of synaptic plasticity. Although all brain neurons express one or several variants coding for the core pore-forming sodium channel α subunit, the expression of the β (β1–4) auxiliary subunits varies greatly. Of particular interest is the β4 subunit, encoded by the Scn4b gene, that is highly expressed in dorsal and ventral (i.e., nucleus accumbens – NAc) striata compared to other brain regions, and that endows sodium channels with unique gating properties. However, its role on neuronal activity, synaptic plasticity, and behaviors related to drugs of abuse remains poorly understood. Combining whole-cell patch-clamp recordings with two-photon calcium imaging in Scn4b knockout (KO) and knockdown mice, we found that Scn4b altered the properties of APs in core accumbens medium spiny neurons (MSNs). These alterations are associated with a reduction of the probability of MSNs to evoke spike-timing-dependent long-term depression (tLTD) and a reduced ability of backpropagating APs to evoke dendritic calcium transients. In contrast, long-term potentiation (tLTP) remained unaffected. Interestingly, we also showed that amphetamine-induced locomotor activity was significantly reduced in male Scn4b KO mice compared to wild-type controls. Taken together, these data indicate that the Scn4b subunit selectively controls tLTD by modulating dendritic calcium transients evoked by backpropagating APs. PMID:28243192

  3. BK Channels Mediate Dopamine Inhibition of Firing in a Subpopulation of Core Nucleus Accumbens Medium Spiny Neurons

    PubMed Central

    Ji, Xincai; Martin, Gilles E.

    2014-01-01

    Dopamine, a key neurotransmitter mediating the rewarding properties of drugs of abuse, is widely believed to exert some of its effects by modulating neuronal activity of nucleus accumbens (NAcc) medium spiny neurons (MSNs). Although its effects on synaptic transmission have been well documented, its regulation of intrinsic neuronal excitability is less understood. In this study, we examined the cellular mechanisms of acute dopamine effects on core accumbens MSNs evoked firing. We found that 0.5 μM A-77636 and 10 μM quinpirole, dopamine D1 (DR1s) and D2 receptor (D2Rs) agonists, respectively, markedly inhibited MSN evoked action potentials. This effect, observed only in about 25% of all neurons, was associated with spike-timing-dependent (STDP) long-term potentiation (tLTP), but not long-term depression (tLTD). Dopamine inhibited evoked firing by compromising subthreshold depolarization, not by altering action potentials themselves. Recordings in voltage-clamp mode revealed that all MSNs expressed fast (IA), slowly inactivating delayed rectifier (Idr), and large conductance voltage- and calcium-activated potassium (BKs) channels . Although A-77636 and quinpirole enhanced IA, its selective blockade by 0.5 μM phrixotoxin-1 had no effect on evoked firing. In contrast, exposing tissue to low TEA concentrations and to 10 μM paxilline, a selective BK channel blocker, prevented D1R agonist from inhibiting MSN firing. This result indicates that dopamine inhibits MSN firing through BK channels in a subpopulation of core accumbens MSNs exclusively associated with spike-timing-dependent long-term potentiation. PMID:25219484

  4. Tonic Inhibition of Accumbal Spiny Neurons by Extrasynaptic α4βδ GABAA Receptors Modulates the Actions of Psychostimulants

    PubMed Central

    Maguire, Edward P.; Macpherson, Tom; Swinny, Jerome D.; Dixon, Claire I.; Herd, Murray B.; Belelli, Delia; Stephens, David N.

    2014-01-01

    Within the nucleus accumbens (NAc), synaptic GABAA receptors (GABAARs) mediate phasic inhibition of medium spiny neurons (MSNs) and influence behavioral responses to cocaine. We demonstrate that both dopamine D1- and D2-receptor-expressing MSNs (D-MSNs) additionally harbor extrasynaptic GABAARs incorporating α4, β, and δ subunits that mediate tonic inhibition, thereby influencing neuronal excitability. Both the selective δ-GABAAR agonist THIP and DS2, a selective positive allosteric modulator, greatly increased the tonic current of all MSNs from wild-type (WT), but not from δ−/− or α4−/− mice. Coupling dopamine and tonic inhibition, the acute activation of D1 receptors (by a selective agonist or indirectly by amphetamine) greatly enhanced tonic inhibition in D1-MSNs but not D2-MSNs. In contrast, prolonged D2 receptor activation modestly reduced the tonic conductance of D2-MSNs. Behaviorally, WT and constitutive α4−/− mice did not differ in their expression of cocaine-conditioned place preference (CPP). Importantly, however, mice with the α4 deletion specific to D1-expressing neurons (α4D1−/−) showed increased CPP. Furthermore, THIP administered systemically or directly into the NAc of WT, but not α4−/− or α4D1−/− mice, blocked cocaine enhancement of CPP. In comparison, α4D2−/− mice exhibited normal CPP, but no cocaine enhancement. In conclusion, dopamine modulation of GABAergic tonic inhibition of D1- and D2-MSNs provides an intrinsic mechanism to differentially affect their excitability in response to psychostimulants and thereby influence their ability to potentiate conditioned reward. Therefore, α4βδ GABAARs may represent a viable target for the development of novel therapeutics to better understand and influence addictive behaviors. PMID:24431441

  5. Inhibitory Synapse Formation in a Co-culture Model Incorporating GABAergic Medium Spiny Neurons and HEK293 Cells Stably Expressing GABAA Receptors

    PubMed Central

    Brown, Laura E.; Fuchs, Celine; Nicholson, Martin W.; Stephenson, F. Anne; Thomson, Alex M.; Jovanovic, Jasmina N.

    2014-01-01

    Inhibitory neurons act in the central nervous system to regulate the dynamics and spatio-temporal co-ordination of neuronal networks. GABA (γ-aminobutyric acid) is the predominant inhibitory neurotransmitter in the brain. It is released from the presynaptic terminals of inhibitory neurons within highly specialized intercellular junctions known as synapses, where it binds to GABAA receptors (GABAARs) present at the plasma membrane of the synapse-receiving, postsynaptic neurons. Activation of these GABA-gated ion channels leads to influx of chloride resulting in postsynaptic potential changes that decrease the probability that these neurons will generate action potentials. During development, diverse types of inhibitory neurons with distinct morphological, electrophysiological and neurochemical characteristics have the ability to recognize their target neurons and form synapses which incorporate specific GABAARs subtypes. This principle of selective innervation of neuronal targets raises the question as to how the appropriate synaptic partners identify each other. To elucidate the underlying molecular mechanisms, a novel in vitro co-culture model system was established, in which medium spiny GABAergic neurons, a highly homogenous population of neurons isolated from the embryonic striatum, were cultured with stably transfected HEK293 cell lines that express different GABAAR subtypes. Synapses form rapidly, efficiently and selectively in this system, and are easily accessible for quantification. Our results indicate that various GABAAR subtypes differ in their ability to promote synapse formation, suggesting that this reduced in vitro model system can be used to reproduce, at least in part, the in vivo conditions required for the recognition of the appropriate synaptic partners and formation of specific synapses. Here the protocols for culturing the medium spiny neurons and generating HEK293 cells lines expressing GABAARs are first described, followed by detailed

  6. Ultrastructural localization of 5'AMP odorant receptor sites on the dendrites of olfactory receptor neurons of the spiny lobster.

    PubMed

    Blaustein, D N; Simmons, R B; Burgess, M F; Derby, C D; Nishikawa, M; Olson, K S

    1993-07-01

    A unique probe--biotinylated adenosine-5'-monophosphate (5'AMP-biotin)--was used in transmission electron microscopic (TEM) studies to localize 5'AMP odorant binding sites on the dendrites of olfactory receptor neurons in the aesthetasc sensilla of the spiny lobster, Panulirus argus. This probe is capable of both binding to and exciting 5'AMP-sensitive olfactory receptor neurons, as revealed through biochemical and electrophysiological assays. TEM studies showed that 5'AMP-biotin binding sites are distributed along the entire dendritic region that is exposed to odorants, including the transitional zone (between the inner and outer dendritic segments, including the ciliary segment) and all of the outer dendritic segment. The density of 5'AMP binding sites per micron2 of membrane is similar along the length of the olfactory dendrite. However, the relative number of 5'AMP-biotin binding sites per micron2 of sensillar area diminishes in the distal 30% of the aesthetasc due to a decrease in the amount of dendritic membrane in that region. The distribution of these 5'AMP binding sites is therefore much more extensive than that of enzymes that inactivate 5'AMP--5'ectonucleotidase/phosphatase--which are restricted to the transitional zone (Gleeson et al., 1991). Taken together, these results suggest that 5'AMP-biotin is labeling 5'AMP-specific olfactory receptor sites that are located along the entire outer dendritic segment and that can be coupled to olfactory transduction. This study represents the first in situ localization of specific olfactory receptor sites using a specific, functionally defined ligand.

  7. Inositol 1,4,5-triphosphate drives glutamatergic and cholinergic inhibition selectively in spiny projection neurons in the striatum.

    PubMed

    Clements, Michael A; Swapna, Immani; Morikawa, Hitoshi

    2013-02-06

    The striatum is critically involved in the selection of appropriate actions in a constantly changing environment. The spiking activity of striatal spiny projection neurons (SPNs), driven by extrinsic glutamatergic inputs, is shaped by local GABAergic and cholinergic networks. For example, it is well established that different types of GABAergic interneurons, activated by extrinsic glutamatergic and local cholinergic inputs, mediate powerful feedforward inhibition of SPN activity. In this study, using mouse striatal slices, we show that glutamatergic and cholinergic inputs exert direct inhibitory regulation of SPN activity via activation of metabotropic glutamate receptors (mGluRs) and muscarinic acetylcholine receptors. While pressure ejection of the group I mGluR (mGluR1/5) agonist DHPG [(S)-3,5-dihydroxyphenylglycine] equally engages both mGluR1 and mGluR5 subtypes, the mGluR-dependent component of IPSCs elicited by intrastriatal electrical stimulation is almost exclusively mediated by the mGluR1 subtype. Ca(2+) release from intracellular stores specifically through inositol 1,4,5-triphospahte receptors (IP(3)Rs) and not ryanodine receptors (RyRs) mediates this form of inhibition by gating two types of Ca(2+)-activated K(+) channels (i.e., small-conductance SK channels and large-conductance BK channels). Conversely, spike-evoked Ca(2+) influx triggers Ca(2+) release solely through RyRs to generate SK-dependent slow afterhyperpolarizations, demonstrating functional segregation of IP(3)Rs and RyRs. Finally, IP(3)-induced Ca(2+) release is uniquely observed in SPNs and not in different types of interneurons in the striatum. These results demonstrate that IP(3)-mediated activation of SK and BK channels provides a robust mechanism for glutamatergic and cholinergic inputs to selectively suppress striatal output neuron activity.

  8. Inositol 1,4,5-Triphosphate Drives Glutamatergic and Cholinergic Inhibition Selectively in Spiny Projection Neurons in the Striatum

    PubMed Central

    Clements, Michael A.; Swapna, Immani; Morikawa, Hitoshi

    2013-01-01

    The striatum is critically involved in the selection of appropriate actions in a constantly changing environment. The spiking activity of striatal spiny projection neurons (SPNs), driven by extrinsic glutamatergic inputs, is shaped by local GABAergic and cholinergic networks. For example, it is well established that different types of GABAergic interneurons, activated by extrinsic glutamatergic and local cholinergic inputs, mediate powerful feedforward inhibition of SPN activity. In this study, using mouse striatal slices, we show that glutamatergic and cholinergic inputs exert direct inhibitory regulation of SPN activity via activation of metabotropic glutamate receptors (mGluRs) and muscarinic acetylcholine receptors. While pressure ejection of the group I mGluR (mGluR1/5) agonist DHPG [(S)-3,5-dihydroxyphenylglycine] equally engages both mGluR1 and mGluR5 subtypes, the mGluR-dependent component of IPSCs elicited by intrastriatal electrical stimulation is almost exclusively mediated by the mGluR1 subtype. Ca2+ release from intracellular stores specifically through inositol 1,4,5-triphospahte receptors (IP3Rs) and not ryanodine receptors (RyRs) mediates this form of inhibition by gating two types of Ca2+ -activated K+ channels (i.e., small-conductance SK channels and large-conductance BK channels). Conversely, spike-evoked Ca2+ influx triggers Ca2+ release solely through RyRs to generate SK-dependent slow afterhyperpolarizations, demonstrating functional segregation of IP3Rs and RyRs. Finally, IP3-induced Ca2+ release is uniquely observed in SPNs and not in different types of interneurons in the striatum. These results demonstrate that IP3-mediated activation of SK and BK channels provides a robust mechanism for glutamatergic and cholinergic inputs to selectively suppress striatal output neuron activity. PMID:23392696

  9. Neuronal Dysfunction in iPSC-Derived Medium Spiny Neurons from Chorea-Acanthocytosis Patients Is Reversed by Src Kinase Inhibition and F-Actin Stabilization.

    PubMed

    Stanslowsky, Nancy; Reinhardt, Peter; Glass, Hannes; Kalmbach, Norman; Naujock, Maximilian; Hensel, Niko; Lübben, Verena; Pal, Arun; Venneri, Anna; Lupo, Francesca; De Franceschi, Lucia; Claus, Peter; Sterneckert, Jared; Storch, Alexander; Hermann, Andreas; Wegner, Florian

    2016-11-23

    Chorea-acanthocytosis (ChAc) is a fatal neurological disorder characterized by red blood cell acanthocytes and striatal neurodegeneration. Recently, severe cell membrane disturbances based on depolymerized cortical actin and an elevated Lyn kinase activity in erythrocytes from ChAc patients were identified. How this contributes to the mechanism of neurodegeneration is still unknown. To gain insight into the pathophysiology, we established a ChAc patient-derived induced pluripotent stem cell model and an efficient differentiation protocol providing a large population of human striatal medium spiny neurons (MSNs), the main target of neurodegeneration in ChAc. Patient-derived MSNs displayed enhanced neurite outgrowth and ramification, whereas synaptic density was similar to controls. Electrophysiological analysis revealed a pathologically elevated synaptic activity in ChAc MSNs. Treatment with the F-actin stabilizer phallacidin or the Src kinase inhibitor PP2 resulted in the significant reduction of disinhibited synaptic currents to healthy control levels, suggesting a Src kinase- and actin-dependent mechanism. This was underlined by increased G/F-actin ratios and elevated Lyn kinase activity in patient-derived MSNs. These data indicate that F-actin stabilization and Src kinase inhibition represent potential therapeutic targets in ChAc that may restore neuronal function.

  10. Ischemic-LTP in striatal spiny neurons of both direct and indirect pathway requires the activation of D1-like receptors and NO/soluble guanylate cyclase/cGMP transmission.

    PubMed

    Arcangeli, Sara; Tozzi, Alessandro; Tantucci, Michela; Spaccatini, Cristiano; de Iure, Antonio; Costa, Cinzia; Di Filippo, Massimiliano; Picconi, Barbara; Giampà, Carmen; Fusco, Francesca Romana; Amoroso, Salvatore; Calabresi, Paolo

    2013-02-01

    Striatal medium-sized spiny neurons (MSNs) are highly vulnerable to ischemia. A brief ischemic insult, produced by oxygen and glucose deprivation (OGD), can induce ischemic long-term potentiation (i-LTP) of corticostriatal excitatory postsynaptic response. Since nitric oxide (NO) is involved in the pathophysiology of brain ischemia and the dopamine D1/D5-receptors (D1-like-R) are expressed in striatal NOS-positive interneurons, we hypothesized a relation between NOS-positive interneurons and striatal i-LTP, involving D1R activation and NO production. We investigated the mechanisms involved in i-LTP induced by OGD in corticostriatal slices and found that the D1-like-R antagonist SCH-23390 prevented i-LTP in all recorded MSNs. Immunofluorescence analysis confirmed the induction of i-LTP in both substance P-positive, (putative D1R-expressing) and adenosine A2A-receptor-positive (putative D2R-expressing) MSNs. Furthermore, i-LTP was dependent on a NOS/cGMP pathway since pharmacological blockade of NOS, guanylate-cyclase, or PKG prevented i-LTP. However, these compounds failed to prevent i-LTP in the presence of a NO donor or cGMP analog, respectively. Interestingly, the D1-like-R antagonism failed to prevent i-LTP when intracellular cGMP was pharmacologically increased. We propose that NO, produced by striatal NOS-positive interneurons via the stimulation of D1-like-R located on these cells, is critical for i-LTP induction in the entire population of MSNs involving a cGMP-dependent pathway.

  11. Ischemic-LTP in striatal spiny neurons of both direct and indirect pathway requires the activation of D1-like receptors and NO/soluble guanylate cyclase/cGMP transmission

    PubMed Central

    Arcangeli, Sara; Tozzi, Alessandro; Tantucci, Michela; Spaccatini, Cristiano; de Iure, Antonio; Costa, Cinzia; Di Filippo, Massimiliano; Picconi, Barbara; Giampà, Carmen; Fusco, Francesca Romana; Amoroso, Salvatore; Calabresi, Paolo

    2013-01-01

    Striatal medium-sized spiny neurons (MSNs) are highly vulnerable to ischemia. A brief ischemic insult, produced by oxygen and glucose deprivation (OGD), can induce ischemic long-term potentiation (i-LTP) of corticostriatal excitatory postsynaptic response. Since nitric oxide (NO) is involved in the pathophysiology of brain ischemia and the dopamine D1/D5-receptors (D1-like-R) are expressed in striatal NOS-positive interneurons, we hypothesized a relation between NOS-positive interneurons and striatal i-LTP, involving D1R activation and NO production. We investigated the mechanisms involved in i-LTP induced by OGD in corticostriatal slices and found that the D1-like-R antagonist SCH-23390 prevented i-LTP in all recorded MSNs. Immunofluorescence analysis confirmed the induction of i-LTP in both substance P-positive, (putative D1R-expressing) and adenosine A2A-receptor-positive (putative D2R-expressing) MSNs. Furthermore, i-LTP was dependent on a NOS/cGMP pathway since pharmacological blockade of NOS, guanylate-cyclase, or PKG prevented i-LTP. However, these compounds failed to prevent i-LTP in the presence of a NO donor or cGMP analog, respectively. Interestingly, the D1-like-R antagonism failed to prevent i-LTP when intracellular cGMP was pharmacologically increased. We propose that NO, produced by striatal NOS-positive interneurons via the stimulation of D1-like-R located on these cells, is critical for i-LTP induction in the entire population of MSNs involving a cGMP-dependent pathway. PMID:23149555

  12. In vivo imaging identifies temporal signature of D1 and D2 medium spiny neurons in cocaine reward.

    PubMed

    Calipari, Erin S; Bagot, Rosemary C; Purushothaman, Immanuel; Davidson, Thomas J; Yorgason, Jordan T; Peña, Catherine J; Walker, Deena M; Pirpinias, Stephen T; Guise, Kevin G; Ramakrishnan, Charu; Deisseroth, Karl; Nestler, Eric J

    2016-03-08

    The reinforcing and rewarding properties of cocaine are attributed to its ability to increase dopaminergic transmission in nucleus accumbens (NAc). This action reinforces drug taking and seeking and leads to potent and long-lasting associations between the rewarding effects of the drug and the cues associated with its availability. The inability to extinguish these associations is a key factor contributing to relapse. Dopamine produces these effects by controlling the activity of two subpopulations of NAc medium spiny neurons (MSNs) that are defined by their predominant expression of either dopamine D1 or D2 receptors. Previous work has demonstrated that optogenetically stimulating D1 MSNs promotes reward, whereas stimulating D2 MSNs produces aversion. However, we still lack a clear understanding of how the endogenous activity of these cell types is affected by cocaine and encodes information that drives drug-associated behaviors. Using fiber photometry calcium imaging we define D1 MSNs as the specific population of cells in NAc that encodes information about drug associations and elucidate the temporal profile with which D1 activity is increased to drive drug seeking in response to contextual cues. Chronic cocaine exposure dysregulates these D1 signals to both prevent extinction and facilitate reinstatement of drug seeking to drive relapse. Directly manipulating these D1 signals using designer receptors exclusively activated by designer drugs prevents contextual associations. Together, these data elucidate the responses of D1- and D2-type MSNs in NAc to acute cocaine and during the formation of context-reward associations and define how prior cocaine exposure selectively dysregulates D1 signaling to drive relapse.

  13. Differential changes in thalamic and cortical excitatory synapses onto striatal spiny projection neurons in a Huntington disease mouse model.

    PubMed

    Kolodziejczyk, Karolina; Raymond, Lynn A

    2016-02-01

    Huntington disease (HD), a neurodegenerative disorder caused by CAG repeat expansion in the gene encoding huntingtin, predominantly affects the striatum, especially the spiny projection neurons (SPN). The striatum receives excitatory input from cortex and thalamus, and the role of the former has been well-studied in HD. Here, we report that mutated huntingtin alters function of thalamostriatal connections. We used a novel thalamostriatal (T-S) coculture and an established corticostriatal (C-S) coculture, generated from YAC128 HD and WT (FVB/NJ background strain) mice, to investigate excitatory neurotransmission onto striatal SPN. SPN in T-S coculture from WT mice showed similar mini-excitatory postsynaptic current (mEPSC) frequency and amplitude as in C-S coculture; however, both the frequency and amplitude were significantly reduced in YAC128 T-S coculture. Further investigation in T-S coculture showed similar excitatory synapse density in WT and YAC128 SPN dendrites by immunostaining, suggesting changes in total dendritic length or probability of release as possible explanations for mEPSC frequency changes. Synaptic N-methyl-D-aspartate receptor (NMDAR) current was similar, but extrasynaptic current, associated with cell death signaling, was enhanced in YAC128 SPN in T-S coculture. Employing optical stimulation of cortical versus thalamic afferents and recording from striatal SPN in brain slice, we found increased glutamate release probability and reduced AMPAR/NMDAR current ratios in thalamostriatal synapses, most prominently in YAC128. Enhanced extrasynaptic NMDAR current in YAC128 SPN was apparent with both cortical and thalamic stimulation. We conclude that thalamic afferents to the striatum are affected early, prior to an overt HD phenotype; however, changes in NMDAR localization in SPN are independent of the source of glutamatergic input.

  14. Type 1 cannabinoid receptor ligands display functional selectivity in a cell culture model of striatal medium spiny projection neurons.

    PubMed

    Laprairie, Robert B; Bagher, Amina M; Kelly, Melanie E M; Dupré, Denis J; Denovan-Wright, Eileen M

    2014-09-05

    Modulation of type 1 cannabinoid receptor (CB1) activity has been touted as a potential means of treating addiction, anxiety, depression, and neurodegeneration. Different agonists of CB1 are known to evoke varied responses in vivo. Functional selectivity is the ligand-specific activation of certain signal transduction pathways at a receptor that can signal through multiple pathways. To understand cannabinoid-specific functional selectivity, different groups have examined the effect of individual cannabinoids on various signaling pathways in heterologous expression systems. In the current study, we compared the functional selectivity of six cannabinoids, including two endocannabinoids (2-arachidonyl glycerol (2-AG) and anandamide (AEA)), two synthetic cannabinoids (WIN55,212-2 and CP55,940), and two phytocannabinoids (cannabidiol (CBD) and Δ(9)-tetrahydrocannabinol (THC)) on arrestin2-, Gα(i/o)-, Gβγ-, Gα(s)-, and Gα(q)-mediated intracellular signaling in the mouse STHdh(Q7/Q7) cell culture model of striatal medium spiny projection neurons that endogenously express CB1. In this system, 2-AG, THC, and CP55,940 were more potent mediators of arrestin2 recruitment than other cannabinoids tested. 2-AG, AEA, and WIN55,212-2, enhanced Gα(i/o) and Gβγ signaling, with 2-AG and AEA treatment leading to increased total CB1 levels. 2-AG, AEA, THC, and WIN55,212-2 also activated Gα(q)-dependent pathways. CP55,940 and CBD both signaled through Gα(s). CP55,940, but not CBD, activated downstream Gα(s) pathways via CB1 targets. THC and CP55,940 promoted CB1 internalization and decreased CB1 protein levels over an 18-h period. These data demonstrate that individual cannabinoids display functional selectivity at CB1 leading to activation of distinct signaling pathways. To effectively match cannabinoids with therapeutic goals, these compounds must be screened for their signaling bias.

  15. In vivo imaging identifies temporal signature of D1 and D2 medium spiny neurons in cocaine reward

    PubMed Central

    Calipari, Erin S.; Bagot, Rosemary C.; Purushothaman, Immanuel; Davidson, Thomas J.; Yorgason, Jordan T.; Peña, Catherine J.; Walker, Deena M.; Pirpinias, Stephen T.; Guise, Kevin G.; Ramakrishnan, Charu; Deisseroth, Karl; Nestler, Eric J.

    2016-01-01

    The reinforcing and rewarding properties of cocaine are attributed to its ability to increase dopaminergic transmission in nucleus accumbens (NAc). This action reinforces drug taking and seeking and leads to potent and long-lasting associations between the rewarding effects of the drug and the cues associated with its availability. The inability to extinguish these associations is a key factor contributing to relapse. Dopamine produces these effects by controlling the activity of two subpopulations of NAc medium spiny neurons (MSNs) that are defined by their predominant expression of either dopamine D1 or D2 receptors. Previous work has demonstrated that optogenetically stimulating D1 MSNs promotes reward, whereas stimulating D2 MSNs produces aversion. However, we still lack a clear understanding of how the endogenous activity of these cell types is affected by cocaine and encodes information that drives drug-associated behaviors. Using fiber photometry calcium imaging we define D1 MSNs as the specific population of cells in NAc that encodes information about drug associations and elucidate the temporal profile with which D1 activity is increased to drive drug seeking in response to contextual cues. Chronic cocaine exposure dysregulates these D1 signals to both prevent extinction and facilitate reinstatement of drug seeking to drive relapse. Directly manipulating these D1 signals using designer receptors exclusively activated by designer drugs prevents contextual associations. Together, these data elucidate the responses of D1- and D2-type MSNs in NAc to acute cocaine and during the formation of context–reward associations and define how prior cocaine exposure selectively dysregulates D1 signaling to drive relapse. PMID:26831103

  16. ΔFosB induction in striatal medium spiny neuron subtypes in response to chronic pharmacological, emotional, and optogenetic stimuli.

    PubMed

    Lobo, Mary Kay; Zaman, Samir; Damez-Werno, Diane M; Koo, Ja Wook; Bagot, Rosemary C; DiNieri, Jennifer A; Nugent, Alexandria; Finkel, Eric; Chaudhury, Dipesh; Chandra, Ramesh; Riberio, Efrain; Rabkin, Jacqui; Mouzon, Ezekiell; Cachope, Roger; Cheer, Joseph F; Han, Ming-Hu; Dietz, David M; Self, David W; Hurd, Yasmin L; Vialou, Vincent; Nestler, Eric J

    2013-11-20

    The transcription factor, ΔFosB, is robustly and persistently induced in striatum by several chronic stimuli, such as drugs of abuse, antipsychotic drugs, natural rewards, and stress. However, very few studies have examined the degree of ΔFosB induction in the two striatal medium spiny neuron (MSN) subtypes. We make use of fluorescent reporter BAC transgenic mice to evaluate induction of ΔFosB in dopamine receptor 1 (D1) enriched and dopamine receptor 2 (D2) enriched MSNs in ventral striatum, nucleus accumbens (NAc) shell and core, and in dorsal striatum (dStr) after chronic exposure to several drugs of abuse including cocaine, ethanol, Δ(9)-tetrahydrocannabinol, and opiates; the antipsychotic drug, haloperidol; juvenile enrichment; sucrose drinking; calorie restriction; the serotonin selective reuptake inhibitor antidepressant, fluoxetine; and social defeat stress. Our findings demonstrate that chronic exposure to many stimuli induces ΔFosB in an MSN-subtype selective pattern across all three striatal regions. To explore the circuit-mediated induction of ΔFosB in striatum, we use optogenetics to enhance activity in limbic brain regions that send synaptic inputs to NAc; these regions include the ventral tegmental area and several glutamatergic afferent regions: medial prefrontal cortex, amygdala, and ventral hippocampus. These optogenetic conditions lead to highly distinct patterns of ΔFosB induction in MSN subtypes in NAc core and shell. Together, these findings establish selective patterns of ΔFosB induction in striatal MSN subtypes in response to chronic stimuli and provide novel insight into the circuit-level mechanisms of ΔFosB induction in striatum.

  17. The presence of cortical neurons in striatal-cortical co-cultures alters the effects of dopamine and BDNF on medium spiny neuron dendritic development

    PubMed Central

    Penrod, Rachel D.; Campagna, Justin; Panneck, Travis; Preese, Laura; Lanier, Lorene M.

    2015-01-01

    Medium spiny neurons (MSNs) are the major striatal neuron and receive synaptic input from both glutamatergic and dopaminergic afferents. These synapses are made on MSN dendritic spines, which undergo density and morphology changes in association with numerous disease and experience-dependent states. Despite wide interest in the structure and function of mature MSNs, relatively little is known about MSN development. Furthermore, most in vitro studies of MSN development have been done in simple striatal cultures that lack any type of non-autologous synaptic input, leaving open the question of how MSN development is affected by a complex environment that includes other types of neurons, glia, and accompanying secreted and cell-associated cues. Here we characterize the development of MSNs in striatal-cortical co-culture, including quantitative morphological analysis of dendritic arborization and spine development, describing progressive changes in density and morphology of developing spines. Overall, MSN growth is much more robust in the striatal-cortical co-culture compared to striatal mono-culture. Inclusion of dopamine (DA) in the co-culture further enhances MSN dendritic arborization and spine density, but the effects of DA on dendritic branching are only significant at later times in development. In contrast, exogenous Brain Derived Neurotrophic Factor (BDNF) has only a minimal effect on MSN development in the co-culture, but significantly enhances MSN dendritic arborization in striatal mono-culture. Importantly, inhibition of NMDA receptors in the co-culture significantly enhances the effect of exogenous BDNF, suggesting that the efficacy of BDNF depends on the cellular environment. Combined, these studies identify specific periods of MSN development that may be particularly sensitive to perturbation by external factors and demonstrate the importance of studying MSN development in a complex signaling environment. PMID:26257605

  18. Prolonged Consumption of Sucrose in a Binge-Like Manner, Alters the Morphology of Medium Spiny Neurons in the Nucleus Accumbens Shell

    PubMed Central

    Klenowski, Paul M.; Shariff, Masroor R.; Belmer, Arnauld; Fogarty, Matthew J.; Mu, Erica W. H.; Bellingham, Mark C.; Bartlett, Selena E.

    2016-01-01

    The modern diet has become highly sweetened, resulting in unprecedented levels of sugar consumption, particularly among adolescents. While chronic long-term sugar intake is known to contribute to the development of metabolic disorders including obesity and type II diabetes, little is known regarding the direct consequences of long-term, binge-like sugar consumption on the brain. Because sugar can cause the release of dopamine in the nucleus accumbens (NAc) similarly to drugs of abuse, we investigated changes in the morphology of neurons in this brain region following short- (4 weeks) and long-term (12 weeks) binge-like sucrose consumption using an intermittent two-bottle choice paradigm. We used Golgi-Cox staining to impregnate medium spiny neurons (MSNs) from the NAc core and shell of short- and long-term sucrose consuming rats and compared these to age-matched water controls. We show that prolonged binge-like sucrose consumption significantly decreased the total dendritic length of NAc shell MSNs compared to age-matched control rats. We also found that the restructuring of these neurons resulted primarily from reduced distal dendritic complexity. Conversely, we observed increased spine densities at the distal branch orders of NAc shell MSNs from long-term sucrose consuming rats. Combined, these results highlight the neuronal effects of prolonged binge-like intake of sucrose on NAc shell MSN morphology. PMID:27047355

  19. Dopamine-dependent long-term depression is expressed in striatal spiny neurons of both direct and indirect pathways: implications for Parkinson's disease.

    PubMed

    Bagetta, Vincenza; Picconi, Barbara; Marinucci, Silvia; Sgobio, Carmelo; Pendolino, Valentina; Ghiglieri, Veronica; Fusco, Francesca R; Giampà, Carmen; Calabresi, Paolo

    2011-08-31

    Striatal medium spiny neurons (MSNs) are divided into two subpopulations exerting distinct effects on motor behavior. Transgenic mice carrying bacterial artificial chromosome (BAC) able to confer cell type-specific expression of enhanced green fluorescent protein (eGFP) for dopamine (DA) receptors have been developed to characterize differences between these subpopulations. Analysis of these mice, in contrast with original pioneering studies, showed that striatal long-term depression (LTD) was expressed in indirect but not in the direct pathway MSNs. To address this mismatch, we applied a new approach using combined BAC technology and receptor immunohistochemistry. We demonstrate that, in physiological conditions, DA-dependent LTD is expressed in both pathways showing that the lack of synaptic plasticity found in D(1) eGFP mice is associated to behavioral deficits. Our findings suggest caution in the use of this tool and indicate that the "striatal segregation" hypothesis might not explain all synaptic dysfunctions in Parkinson's disease.

  20. Delayed post-treatment with bone marrow-derived mesenchymal stem cells is neurorestorative of striatal medium-spiny projection neurons and improves motor function after neonatal rat hypoxia-ischemia.

    PubMed

    Cameron, Stella H; Alwakeel, Amr J; Goddard, Liping; Hobbs, Catherine E; Gowing, Emma K; Barnett, Elizabeth R; Kohe, Sarah E; Sizemore, Rachel J; Oorschot, Dorothy E

    2015-09-01

    Perinatal hypoxia-ischemia is a major cause of striatal injury and may lead to cerebral palsy. This study investigated whether delayed administration of bone marrow-derived mesenchymal stem cells (MSCs), at one week after neonatal rat hypoxia-ischemia, was neurorestorative of striatal medium-spiny projection neurons and improved motor function. The effect of a subcutaneous injection of a high-dose, or a low-dose, of MSCs was investigated in stereological studies. Postnatal day (PN) 7 pups were subjected to hypoxia-ischemia. At PN14, pups received treatment with either MSCs or diluent. A subset of high-dose pups, and their diluent control pups, were also injected intraperitoneally with bromodeoxyuridine (BrdU), every 24h, on PN15, PN16 and PN17. This permitted tracking of the migration and survival of neuroblasts originating from the subventricular zone into the adjacent injured striatum. Pups were euthanized on PN21 and the absolute number of striatal medium-spiny projection neurons was measured after immunostaining for DARPP-32 (dopamine- and cAMP-regulated phosphoprotein-32), double immunostaining for BrdU and DARPP-32, and after cresyl violet staining alone. The absolute number of striatal immunostained calretinin interneurons was also measured. There was a statistically significant increase in the absolute number of DARPP-32-positive, BrdU/DARPP-32-positive, and cresyl violet-stained striatal medium-spiny projection neurons, and fewer striatal calretinin interneurons, in the high-dose mesenchymal stem cell (MSC) group compared to their diluent counterparts. A high-dose of MSCs restored the absolute number of these neurons to normal uninjured levels, when compared with previous stereological data on the absolute number of cresyl violet-stained striatal medium-spiny projection neurons in the normal uninjured brain. For the low-dose experiment, in which cresyl violet-stained striatal medium-spiny neurons alone were measured, there was a lower statistically

  1. Opposite Effects of mGluR1a and mGluR5 Activation on Nucleus Accumbens Medium Spiny Neuron Dendritic Spine Density

    PubMed Central

    Gross, Kellie S.; Brandner, Dieter D.; Martinez, Luis A.; Olive, M. Foster; Meisel, Robert L.

    2016-01-01

    The group I metabotropic glutamate receptors (mGluR1a and mGluR5) are important modulators of neuronal structure and function. Although these receptors share common signaling pathways, they are capable of having distinct effects on cellular plasticity. We investigated the individual effects of mGluR1a or mGluR5 activation on dendritic spine density in medium spiny neurons in the nucleus accumbens (NAc), which has become relevant with the potential use of group I mGluR based therapeutics in the treatment of drug addiction. We found that systemic administration of mGluR subtype-specific positive allosteric modulators had opposite effects on dendritic spine densities. Specifically, mGluR5 positive modulation decreased dendritic spine densities in the NAc shell and core, but was without effect in the dorsal striatum, whereas increased spine densities in the NAc were observed with mGluR1a positive modulation. Additionally, direct activation of mGluR5 via CHPG administration into the NAc also decreased the density of dendritic spines. These data provide insight on the ability of group I mGluRs to induce structural plasticity in the NAc and demonstrate that the group I mGluRs are capable of producing not just distinct, but opposing, effects on dendritic spine density. PMID:27618534

  2. No Evidence for Sex Differences in the Electrophysiological Properties and Excitatory Synaptic Input onto Nucleus Accumbens Shell Medium Spiny Neurons123

    PubMed Central

    Will, Tyler; Hauser, Caitlin A.; Cao, Jinyan

    2016-01-01

    Sex differences exist in how the brain regulates motivated behavior and reward, both in normal and pathological contexts. Investigations into the underlying neural mechanisms have targeted the striatal brain regions, including the dorsal striatum and nucleus accumbens core and shell. These investigations yield accumulating evidence of sexually different electrophysiological properties, excitatory synaptic input, and sensitivity to neuromodulator/hormone action in select striatal regions both before and after puberty. It is unknown whether the electrical properties of neurons in the nucleus accumbens shell differ by sex, and whether sex differences in excitatory synaptic input are present before puberty. To test the hypothesis that these properties differ by sex, we performed whole-cell patch-clamp recordings on male and female medium spiny neurons (MSNs) in acute brain slices obtained from prepubertal rat nucleus accumbens shell. We analyzed passive and active electrophysiological properties, and miniature EPSCs (mEPSCs). No sex differences were detected; this includes those properties, such as intrinsic excitability, action potential afterhyperpolarization, threshold, and mEPSC frequency, that have been found to differ by sex in other striatal regions and/or developmental periods. These findings indicate that, unlike other striatal brain regions, the electrophysiological properties of nucleus accumbens shell MSNs do not differ by sex. Overall, it appears that sex differences in striatal function, including motivated behavior and reward, are likely mediated by other factors and striatal regions. PMID:27022621

  3. gamma-Hydroxybutyrate (GHB) induces GABA(B) receptor independent intracellular Ca2+ transients in astrocytes, but has no effect on GHB or GABA(B) receptors of medium spiny neurons in the nucleus accumbens.

    PubMed

    Molnár, T; Antal, K; Nyitrai, G; Emri, Z

    2009-08-18

    We report on cellular actions of the illicit recreational drug gamma-hydroxybutyrate (GHB) in the brain reward area nucleus accumbens. First, we compared the effects of GHB and the GABA(B) receptor agonist baclofen. Neither of them affected the membrane currents of medium spiny neurons in rat nucleus accumbens slices. GABAergic and glutamatergic synaptic potentials of medium spiny neurons, however, were reduced by baclofen but not GHB. These results indicate the lack of GHB as well as postsynaptic GABA(B) receptors, and the presence of GHB insensitive presynaptic GABA(B) receptors in medium spiny neurons. In astrocytes GHB induced intracellular Ca(2+) transients, preserved in slices from GABA(B) receptor type 1 subunit knockout mice. The effects of tetrodotoxin, zero added Ca(2+) with/without intracellular Ca(2+) store depletor cyclopiazonic acid or vacuolar H-ATPase inhibitor bafilomycin A1 indicate that GHB-evoked Ca(2+) transients depend on external Ca(2+) and intracellular Ca(2+) stores, but not on vesicular transmitter release. GHB-induced astrocytic Ca(2+) transients were not affected by the GHB receptor-specific antagonist NCS-382, suggesting the presence of a novel NCS-382-insensitive target for GHB in astrocytes. The activation of astrocytes by GHB implies their involvement in physiological actions of GHB. Our findings disclose a novel profile of GHB action in the nucleus accumbens. Here, unlike in other brain areas, GHB does not act on GABA(B) receptors, but activates an NCS-382 insensitive GHB-specific target in a subpopulation of astrocytes. The lack of either post- or presynaptic effects on medium spiny neurons in the nucleus accumbens distinguishes GHB from many drugs and natural rewards with addictive properties and might explain why GHB has only a weak reinforcing capacity.

  4. Synaptic connections between layer 4 spiny neurone-layer 2/3 pyramidal cell pairs in juvenile rat barrel cortex: physiology and anatomy of interlaminar signalling within a cortical column.

    PubMed

    Feldmeyer, Dirk; Lübke, Joachim; Silver, R Angus; Sakmann, Bert

    2002-02-01

    Whole-cell voltage recordings were obtained from 64 synaptically coupled excitatory layer 4 (L4) spiny neurones and L2/3 pyramidal cells in acute slices of the somatosensory cortex ('barrel' cortex) of 17- to 23-days-old rats. Single action potentials (APs) in the L4 spiny neurone evoked single unitary EPSPs in the L2/3 pyramidal cell with a peak amplitude of 0.7 +/- 0.6 mV. The average latency was 2.1 +/- 0.6 ms, the rise time was 0.8 +/- 0.3 ms and the decay time constant was 12.7 +/- 3.5 ms. The percentage of failures of an AP in a L4 spiny neurone to evoke a unitary EPSP in the L2/3 pyramidal cell was 4.9 +/- 8.8 % and the coefficient of variation (c.v.) of the unitary EPSP amplitude was 0.27 +/- 0.13. Both c.v. and percentage of failures decreased with increased average EPSP amplitude. Postsynaptic glutamate receptors (GluRs) in L2/3 pyramidal cells were of the N-methyl-D-aspartate (NMDA) receptor (NMDAR) and the non-NMDAR type. At -60 mV in the presence of extracellular Mg2+ (1 mM), 29 +/- 15 % of the EPSP voltage-time integral was blocked by NMDAR antagonists. In 0 Mg2+, the NMDAR/AMPAR ratio of the EPSC was 0.50 +/- 0.29, about half the value obtained for L4 spiny neurone connections. Burst stimulation of L4 spiny neurones showed that EPSPs in L2/3 pyramidal cells depressed over a wide range of frequencies (1-100 s(-1) ). However, at higher frequencies (30 s(-1)) EPSP summation overcame synaptic depression so that the summed EPSP was larger than the first EPSP amplitude in the train. The number of putative synaptic contacts established by the axonal collaterals of the L4 projection neurone with the target neurone in layer 2/3 varied between 4 and 5, with an average of 4.5 +/- 0.5 (n = 13 pairs). Synapses were established on basal dendrites of the pyramidal cell. Their mean geometric distance from the pyramidal cell soma was 67 +/- 34 microm (range, 16-196 microm). The results suggest that each connected L4 spiny neurone produces a weak but reliable EPSP in

  5. Cortical regulation of striatal medium spiny neuron dendritic remodeling in parkinsonism: modulation of glutamate release reverses dopamine depletion-induced dendritic spine loss.

    PubMed

    Garcia, Bonnie G; Neely, M Diana; Deutch, Ariel Y

    2010-10-01

    Striatal medium spiny neurons (MSNs) receive glutamatergic afferents from the cerebral cortex and dopaminergic inputs from the substantia nigra (SN). Striatal dopamine loss decreases the number of MSN dendritic spines. This loss of spines has been suggested to reflect the removal of tonic dopamine inhibitory control over corticostriatal glutamatergic drive, with increased glutamate release culminating in MSN spine loss. We tested this hypothesis in two ways. We first determined in vivo if decortication reverses or prevents dopamine depletion-induced spine loss by placing motor cortex lesions 4 weeks after, or at the time of, 6-hydroxydopamine lesions of the SN. Animals were sacrificed 4 weeks after cortical lesions. Motor cortex lesions significantly reversed the loss of MSN spines elicited by dopamine denervation; a similar effect was observed in the prevention experiment. We then determined if modulating glutamate release in organotypic cocultures prevented spine loss. Treatment of the cultures with the mGluR2/3 agonist LY379268 to suppress corticostriatal glutamate release completely blocked spine loss in dopamine-denervated cultures. These studies provide the first evidence to show that MSN spine loss associated with parkinsonism can be reversed and point to suppression of corticostriatal glutamate release as a means of slowing progression in Parkinson's disease.

  6. The distinct role of medium spiny neurons and cholinergic interneurons in the D₂/A₂A receptor interaction in the striatum: implications for Parkinson's disease.

    PubMed

    Tozzi, Alessandro; de Iure, Antonio; Di Filippo, Massimiliano; Tantucci, Michela; Costa, Cinzia; Borsini, Franco; Ghiglieri, Veronica; Giampà, Carmen; Fusco, Francesca Romana; Picconi, Barbara; Calabresi, Paolo

    2011-02-02

    A(2A) adenosine receptor antagonists are currently under investigation as potential therapeutic agents for Parkinson's disease (PD). However, the molecular mechanisms underlying this therapeutic effect is still unclear. A functional antagonism exists between A(2A) adenosine and D(2) dopamine (DA) receptors that are coexpressed in striatal medium spiny neurons (MSNs) of the indirect pathway. Since this interaction could also occur in other neuronal subtypes, we have analyzed the pharmacological modulation of this relationship in murine MSNs of the direct and indirect pathways as well in striatal cholinergic interneurons. Under physiological conditions, endogenous cannabinoids (eCBs) play a major role in the inhibitory effect on striatal glutamatergic transmission exerted by the concomitant activation of D(2) DA receptors and blockade of A(2A) receptors in both D(2)- and D(1)-expressing striatal MSNs. In experimental models of PD, the inhibition of striatal glutamatergic activity exerted by D(2) receptor activation did not require the concomitant inhibition of A(2A) receptors, while it was still dependent on the activation of CB(1) receptors in both D(2)- and D(1)-expressing MSNs. Interestingly, the antagonism of M1 muscarinic receptors blocked the effects of D(2)/A(2A) receptor modulation on MSNs. Moreover, in cholinergic interneurons we found coexpression of D(2) and A(2A) receptors and a reduction of the firing frequency exerted by the same pharmacological agents that reduced excitatory transmission in MSNs. This evidence supports the hypothesis that striatal cholinergic interneurons, projecting to virtually all MSN subtypes, are involved in the D(2)/A(2A) and endocannabinoid-mediated effects observed on both subpopulations of MSNs in physiological conditions and in experimental PD.

  7. Enhanced cocaine-induced locomotor sensitization and intrinsic excitability of NAc medium spiny neurons in adult but not adolescent rats susceptible to diet-induced obesity

    PubMed Central

    Oginsky, Max F.; Maust, Joel D.; Corthell, John T.; Ferrario, Carrie R.

    2015-01-01

    Rationale Basal and diet-induced differences in mesolimbic function, particularly within the nucleus accumbens (NAc), may contribute to human obesity; these differences may be more pronounced in susceptible populations. Objectives We determined whether there are differences in cocaine-induced behavioral plasticity in rats that are susceptible vs. resistant to diet-induced obesity, and basal differences in the striatal neuron function in adult and adolescent obesity-prone and obesity-resistant rats. Methods Susceptible and resistant outbred rats were identified based on “junk-food” diet-induced obesity. Then, the induction and expression of cocaine-induced locomotor sensitization, which is mediated by enhanced striatal function and is associated with increased motivation for rewards and reward-paired cues, were evaluated. Basal differences in mesolimbic function were examined in selectively bred obesity-prone and obesity-resistant rats (P70-80 and P30-40) using both cocaine induced locomotion and whole-cell patch clamping approaches in NAc core medium spiny neurons (MSNs). Results In rats that became obese after eating “junk-food”, the expression of locomotor sensitization was enhanced compared to non-obese rats, with similarly strong responses to 7.5 and 15 mg/kg cocaine. Without diet manipulation, obesity-prone rats were hyper-responsive to the acute locomotor-activating effects of cocaine, and the intrinsic excitability of NAc core MSNs was enhanced by ~60% at positive and negative potentials. These differences were present in adult, but not adolescent rats. Post-synaptic glutamatergic transmission was similar between groups. Conclusions Mesolimbic systems, particularly NAc MSNs, are hyper-responsive in obesity-prone individuals; and interactions between predisposition and experience influence neurobehavioral plasticity in ways that may promote weight gain and hamper weight loss in susceptible rats. PMID:26612617

  8. Novel fast adapting interneurons mediate cholinergic-induced fast GABAA inhibitory postsynaptic currents in striatal spiny neurons.

    PubMed

    Faust, Thomas W; Assous, Maxime; Shah, Fulva; Tepper, James M; Koós, Tibor

    2015-07-01

    Previous work suggests that neostriatal cholinergic interneurons control the activity of several classes of GABAergic interneurons through fast nicotinic receptor-mediated synaptic inputs. Although indirect evidence has suggested the existence of several classes of interneurons controlled by this mechanism, only one such cell type, the neuropeptide-Y-expressing neurogliaform neuron, has been identified to date. Here we tested the hypothesis that in addition to the neurogliaform neurons that elicit slow GABAergic inhibitory responses, another interneuron type exists in the striatum that receives strong nicotinic cholinergic input and elicits conventional fast GABAergic synaptic responses in projection neurons. We obtained in vitro slice recordings from double transgenic mice in which Channelrhodopsin-2 was natively expressed in cholinergic neurons and a population of serotonin receptor-3a-Cre-expressing GABAergic interneurons were visualized with tdTomato. We show that among the targeted GABAergic interneurons a novel type of interneuron, termed the fast-adapting interneuron, can be identified that is distinct from previously known interneurons based on immunocytochemical and electrophysiological criteria. We show using optogenetic activation of cholinergic inputs that fast-adapting interneurons receive a powerful supra-threshold nicotinic cholinergic input in vitro. Moreover, fast adapting neurons are densely connected to projection neurons and elicit fast, GABAA receptor-mediated inhibitory postsynaptic current responses. The nicotinic receptor-mediated activation of fast-adapting interneurons may constitute an important mechanism through which cholinergic interneurons control the activity of projection neurons and perhaps the plasticity of their synaptic inputs when animals encounter reinforcing or otherwise salient stimuli.

  9. Aneurysms of medium-sized arteries in Marfan syndrome.

    PubMed

    Awais, Mazen; Williams, David M; Deeb, G Michael; Shea, Michael J

    2013-11-01

    Marfan syndrome is a relatively common connective tissue disorder that causes skin, ocular, skeletal, and cardiovascular abnormalities. High morbidity and mortality occur with aortic aneurysm and dissection. Other large-artery aneurysms, including carotid, subclavian, and iliac artery aneurysms, have also been associated with Marfan syndrome. It is not clear whether small- to medium-sized artery aneurysms are associated with Marfan syndrome. This report describes 4 patients with Marfan syndrome who have associated small- to medium-sized artery aneurysms with several complications. Additional investigations are needed to determine whether Marfan syndrome can cause small- to medium-sized artery aneurysms and how patients with these aneurysms should be treated.

  10. Sensing Positive versus Negative Reward Signals through Adenylyl Cyclase-Coupled GPCRs in Direct and Indirect Pathway Striatal Medium Spiny Neurons

    PubMed Central

    Nair, Anu G.; Eriksson, Olivia; Vincent, Pierre

    2015-01-01

    Transient changes in striatal dopamine (DA) concentration are considered to encode a reward prediction error (RPE) in reinforcement learning tasks. Often, a phasic DA change occurs concomitantly with a dip in striatal acetylcholine (ACh), whereas other neuromodulators, such as adenosine (Adn), change slowly. There are abundant adenylyl cyclase (AC) coupled GPCRs for these neuromodulators in striatal medium spiny neurons (MSNs), which play important roles in plasticity. However, little is known about the interaction between these neuromodulators via GPCRs. The interaction between these transient neuromodulator changes and the effect on cAMP/PKA signaling via Golf- and Gi/o-coupled GPCR are studied here using quantitative kinetic modeling. The simulations suggest that, under basal conditions, cAMP/PKA signaling could be significantly inhibited in D1R+ MSNs via ACh/M4R/Gi/o and an ACh dip is required to gate a subset of D1R/Golf-dependent PKA activation. Furthermore, the interaction between ACh dip and DA peak, via D1R and M4R, is synergistic. In a similar fashion, PKA signaling in D2+ MSNs is under basal inhibition via D2R/Gi/o and a DA dip leads to a PKA increase by disinhibiting A2aR/Golf, but D2+ MSNs could also respond to the DA peak via other intracellular pathways. This study highlights the similarity between the two types of MSNs in terms of high basal AC inhibition by Gi/o and the importance of interactions between Gi/o and Golf signaling, but at the same time predicts differences between them with regard to the sign of RPE responsible for PKA activation. SIGNIFICANCE STATEMENT Dopamine transients are considered to carry reward-related signal in reinforcement learning. An increase in dopamine concentration is associated with an unexpected reward or salient stimuli, whereas a decrease is produced by omission of an expected reward. Often dopamine transients are accompanied by other neuromodulatory signals, such as acetylcholine and adenosine. We highlight the

  11. Reacquisition of cocaine conditioned place preference and its inhibition by previous social interaction preferentially affect D1-medium spiny neurons in the accumbens corridor

    PubMed Central

    Prast, Janine M.; Schardl, Aurelia; Schwarzer, Christoph; Dechant, Georg; Saria, Alois; Zernig, Gerald

    2014-01-01

    We investigated if counterconditioning with dyadic (i.e., one-to-one) social interaction, a strong inhibitor of the subsequent reacquisition of cocaine conditioned place preference (CPP), differentially modulates the activity of the diverse brain regions oriented along a mediolateral corridor reaching from the interhemispheric sulcus to the anterior commissure, i.e., the nucleus of the vertical limb of the diagonal band, the medial septal nucleus, the major island of Calleja, the intermediate part of the lateral septal nucleus, and the medial accumbens shell and core. We also investigated the involvement of the lateral accumbens core and the dorsal caudate putamen. The anterior cingulate 1 (Cg1) region served as a negative control. Contrary to our expectations, we found that all regions of the accumbens corridor showed increased expression of the early growth response protein 1 (EGR1, Zif268) in rats 2 h after reacquisition of CPP for cocaine after a history of cocaine CPP acquisition and extinction. Previous counterconditioning with dyadic social interaction inhibited both the reacquisition of cocaine CPP and the activation of the whole accumbens corridor. EGR1 activation was predominantly found in dynorphin-labeled cells, i.e., presumably D1 receptor-expressing medium spiny neurons (D1-MSNs), with D2-MSNs (immunolabeled with an anti-DRD2 antibody) being less affected. Cholinergic interneurons or GABAergic interneurons positive for parvalbumin, neuropeptide Y or calretinin were not involved in these CPP-related EGR1 changes. Glial cells did not show any EGR1 expression either. The present findings could be of relevance for the therapy of impaired social interaction in substance use disorders, depression, psychosis, and autism spectrum disorders. PMID:25309368

  12. Functional and structural specific roles of activity-driven BDNF within circuits formed by single spiny stellate neurons of the barrel cortex.

    PubMed

    Sun, Qian-Quan; Zhang, Zhi; Sun, June; Nair, Anand S; Petrus, Dan P; Zhang, Chunzhao

    2014-01-01

    Brain derived neurotrophic factor (BDNF) plays key roles in several neurodevelopmental disorders and actions of pharmacological treatments. However, it is unclear how specific BDNF's effects are on different circuit components. Current studies have largely focused on the role of BDNF in modification of synaptic development. The precise roles of BDNF in the refinement of a functional circuit in vivo remain unclear. Val66Met polymorphism of BDNF may be associated with increased risk for cognitive impairments and is mediated at least in part by activity-dependent trafficking and/or secretion of BDNF. Using mutant mice that lacked activity-driven BDNF expression (bdnf-KIV), we previously reported that experience regulation of the cortical GABAergic network is mediated by activity-driven BDNF expression. Here, we demonstrate that activity-driven BDNF's effects on circuits formed by the layer IV spiny stellate cells are highly specific. Structurally, dendritic but not axonal morphology was altered in the mutant. Physiologically, GABAergic but not glutamatergic synapses were severely affected. The effects on GABA transmission occurs via presynaptic alteration of calcium-dependent release probability. These results suggest that neuronal activity through activity-driven BDNF expression, can selectively regulate specific features of layer IV circuits in vivo. We postulate that the role of activity-dependent BDNF is to modulate the computational ability of circuits that relate to the gain control (i.e., feed-forward inhibition); whereas the basic wiring of circuits relevant to the sensory pathway is spared. Gain control modulation within cortical circuits has broad impact on cognitive processing and brain state-transitions. Cognitive behavior and mode is determined by brain states, thus the studying of circuit alteration by endogenous BDNF provides insights into the cellular and molecular mechanisms of diseases mediated by BDNF.

  13. Activation of mGluR5 induces spike afterdepolarization and enhanced excitability in medium spiny neurons of the nucleus accumbens by modulating persistent Na+ currents

    PubMed Central

    D’Ascenzo, Marcello; Podda, Maria Vittoria; Fellin, Tommaso; Azzena, Gian Battista; Haydon, Philip; Grassi, Claudio

    2009-01-01

    The involvement of metabotropic glutamate receptors type 5 (mGluR5) in drug-induced behaviours is well-established but limited information is available on their functional roles in addiction-relevant brain areas like the nucleus accumbens (NAc). This study demonstrates that pharmacological and synaptic activation of mGluR5 increases the spike discharge of medium spiny neurons (MSNs) in the NAc. This effect was associated with the appearance of a slow afterdepolarization (ADP) which, in voltage-clamp experiments, was recorded as a slowly inactivating inward current. Pharmacological studies showed that ADP was elicited by mGluR5 stimulation via G-protein-dependent activation of phospholipase C and elevation of intracellular Ca2+ levels. Both ADP and spike aftercurrents were significantly inhibited by the Na+ channel-blocker, tetrodotoxin (TTX). Moreover, the selective blockade of persistent Na+ currents (INaP), achieved by NAc slice pre-incubation with 20 nm TTX or 10 μm riluzole, significantly reduced the ADP amplitude, indicating that this type of Na+ current is responsible for the mGluR5-dependent ADP. mGluR5 activation also produced significant increases in INaP, and the pharmacological blockade of this current prevented the mGluR5-induced enhancement of spike discharge. Collectively, these data suggest that mGluR5 activation upregulates INaP in MSNs of the NAc, thereby inducing an ADP that results in enhanced MSN excitability. Activation of mGluR5 will significantly alter spike firing in MSNs in vivo, and this effect could be an important mechanism by which these receptors mediate certain aspects of drug-induced behaviours. PMID:19433572

  14. Functional and structural specific roles of activity-driven BDNF within circuits formed by single spiny stellate neurons of the barrel cortex

    PubMed Central

    Sun, Qian-Quan; Zhang, Zhi; Sun, June; Nair, Anand S.; Petrus, Dan P.; Zhang, Chunzhao

    2014-01-01

    Brain derived neurotrophic factor (BDNF) plays key roles in several neurodevelopmental disorders and actions of pharmacological treatments. However, it is unclear how specific BDNF’s effects are on different circuit components. Current studies have largely focused on the role of BDNF in modification of synaptic development. The precise roles of BDNF in the refinement of a functional circuit in vivo remain unclear. Val66Met polymorphism of BDNF may be associated with increased risk for cognitive impairments and is mediated at least in part by activity-dependent trafficking and/or secretion of BDNF. Using mutant mice that lacked activity-driven BDNF expression (bdnf-KIV), we previously reported that experience regulation of the cortical GABAergic network is mediated by activity-driven BDNF expression. Here, we demonstrate that activity-driven BDNF’s effects on circuits formed by the layer IV spiny stellate cells are highly specific. Structurally, dendritic but not axonal morphology was altered in the mutant. Physiologically, GABAergic but not glutamatergic synapses were severely affected. The effects on GABA transmission occurs via presynaptic alteration of calcium-dependent release probability. These results suggest that neuronal activity through activity-driven BDNF expression, can selectively regulate specific features of layer IV circuits in vivo. We postulate that the role of activity-dependent BDNF is to modulate the computational ability of circuits that relate to the gain control (i.e., feed-forward inhibition); whereas the basic wiring of circuits relevant to the sensory pathway is spared. Gain control modulation within cortical circuits has broad impact on cognitive processing and brain state-transitions. Cognitive behavior and mode is determined by brain states, thus the studying of circuit alteration by endogenous BDNF provides insights into the cellular and molecular mechanisms of diseases mediated by BDNF. PMID:25414642

  15. Segregation and Crosstalk of D1 Receptor-Mediated Activation of ERK in Striatal Medium Spiny Neurons upon Acute Administration of Psychostimulants

    PubMed Central

    Gutierrez-Arenas, Omar; Eriksson, Olivia; Hellgren Kotaleski, Jeanette

    2014-01-01

    The convergence of corticostriatal glutamate and dopamine from the midbrain in the striatal medium spiny neurons (MSN) triggers synaptic plasticity that underlies reinforcement learning and pathological conditions such as psychostimulant addiction. The increase in striatal dopamine produced by the acute administration of psychostimulants has been found to activate not only effectors of the AC5/cAMP/PKA signaling cascade such as GluR1, but also effectors of the NMDAR/Ca2+/RAS cascade such as ERK. The dopamine-triggered effects on both these cascades are mediated by D1R coupled to Golf but while the phosphorylation of GluR1 is affected by reductions in the available amount of Golf but not of D1R, the activation of ERK follows the opposite pattern. This segregation is puzzling considering that D1R-induced Golf activation monotonically increases with DA and that there is crosstalk from the AC5/cAMP/PKA cascade to the NMDAR/Ca2+/RAS cascade via a STEP (a tyrosine phosphatase). In this work, we developed a signaling model which accounts for this segregation based on the assumption that a common pool of D1R and Golf is distributed in two D1R/Golf signaling compartments. This model integrates a relatively large amount of experimental data for neurons in vivo and in vitro. We used it to explore the crosstalk topologies under which the sensitivities of the AC5/cAMP/PKA signaling cascade to reductions in D1R or Golf are transferred or not to the activation of ERK. We found that the sequestration of STEP by its substrate ERK together with the insensitivity of STEP activity on targets upstream of ERK (i.e. Fyn and NR2B) to PKA phosphorylation are able to explain the experimentally observed segregation. This model provides a quantitative framework for simulation based experiments to study signaling required for long term potentiation in MSNs. PMID:24499932

  16. Effects of alcohol on the membrane excitability and synaptic transmission of medium spiny neurons in the nucleus accumbens

    PubMed Central

    Marty, Vincent N.; Spigelman, Igor

    2013-01-01

    Chronic and excessive alcohol drinking lead to alcohol dependence and loss of control over alcohol consumption, with serious detrimental health consequences. Chronic alcohol exposure followed by protracted withdrawal causes profound alterations in the brain reward system that leads to marked changes in reinforcement mechanisms and motivational state. These long-lasting neuroadaptations are thought to contribute to the development of cravings and relapse. The nucleus accumbens (NAcc), a central component of the brain reward system, plays a critical role in alcohol-induced neuroadaptive changes underlying alcohol-seeking behaviors. Here we review the findings that chronic alcohol exposure produces long-lasting neuroadaptive changes in various ion channels that govern intrinsic membrane properties and neuronal excitability, as well as excitatory and inhibitory synaptic transmission in the NAcc that underlie alcohol-seeking behavior during protracted withdrawal. PMID:22445807

  17. Quantitative high-throughput gene expression profiling of human striatal development to screen stem cell–derived medium spiny neurons

    PubMed Central

    Straccia, Marco; Garcia-Diaz Barriga, Gerardo; Sanders, Phil; Bombau, Georgina; Carrere, Jordi; Mairal, Pedro Belio; Vinh, Ngoc-Nga; Yung, Sun; Kelly, Claire M; Svendsen, Clive N; Kemp, Paul J; Arjomand, Jamshid; Schoenfeld, Ryan C; Alberch, Jordi; Allen, Nicholas D; Rosser, Anne E; Canals, Josep M

    2015-01-01

    A systematic characterization of the spatio-temporal gene expression during human neurodevelopment is essential to understand brain function in both physiological and pathological conditions. In recent years, stem cell technology has provided an in vitro tool to recapitulate human development, permitting also the generation of human models for many diseases. The correct differentiation of human pluripotent stem cell (hPSC) into specific cell types should be evaluated by comparison with specific cells/tissue profiles from the equivalent adult in vivo organ. Here, we define by a quantitative high-throughput gene expression analysis the subset of specific genes of the whole ganglionic eminence (WGE) and adult human striatum. Our results demonstrate that not only the number of specific genes is crucial but also their relative expression levels between brain areas. We next used these gene profiles to characterize the differentiation of hPSCs. Our findings demonstrate a temporal progression of gene expression during striatal differentiation of hPSCs from a WGE toward an adult striatum identity. Present results establish a gene expression profile to qualitatively and quantitatively evaluate the telencephalic hPSC-derived progenitors eventually used for transplantation and mature striatal neurons for disease modeling and drug-screening. PMID:26417608

  18. Workplace Health Promotion within Small and Medium-Sized Enterprises

    ERIC Educational Resources Information Center

    Moore, Ann; Parahoo, Kader; Fleming, Paul

    2010-01-01

    Purpose: The purpose of this study is to explore managers' understanding of workplace health promotion (WHP) and experiences of WHP activity within small and medium-sized enterprises (SMEs) in a Health and Social Care Trust area of Northern Ireland. The paper aims to focus on engagement with activities within the context of prevention of…

  19. Historical Research and Medium-Sized Public Libraries: The Potential.

    ERIC Educational Resources Information Center

    Piehl, Charles K.

    1982-01-01

    Discusses the special collections and archival materials often found in medium-sized public libraries which should be fully used by historical researchers. It is suggested that public libraries need to advertise their collections which are of historical interest and to be more aware of the needs of the historical researcher. (Author/JL)

  20. Promoting Learning in Small and Medium-Sized Enterprises.

    ERIC Educational Resources Information Center

    Hughes, Maria; Gray, Sue

    1998-01-01

    In 1996, small and medium-sized enterprises constituted 99% of all businesses in the United Kingdom in all but the electricity, gas, and water supply sector, providing 46% of nongovernment employment. SMEs' concern with day-to-day demands leaves them with limited time and resources to consider their training needs. Although providing support and…

  1. Systematic Classifier OF Manufacturing Processes For Medium Size Shafts

    NASA Astrophysics Data System (ADS)

    Lychagin, D. V.; Lasukov, A. A.; Walter, A. V.; Arkhipova, D. A.

    2016-04-01

    The article considers some issues of increasing efficiency of manufacturing preparation as a part of manufacturing processes design at a machine building enterprise. A tree of routing manufacturing processes for machining shafts of medium size is described as an example of clustering parts according to their structural and technological characteristics. Processing route for a certain part included into a certain group is developed through choosing machining operations for elementary surfaces of a part from the process route developed for a template representative of the group.

  2. Medium-size high-temperature gas-cooled reactor

    SciTech Connect

    Peinado, C.O.; Koutz, S.L.

    1980-08-01

    This report summarizes high-temperature gas-cooled reactor (HTGR) experience for the 40-MW(e) Peach Bottom Nuclear Generating Station of Philadelphia Electric Company and the 330-MW(e) Fort St. Vrain Nuclear Generating Station of the Public Service Company of Colorado. Both reactors are graphite moderated and helium cooled, operating at approx. 760/sup 0/C (1400/sup 0/F) and using the uranium/thorium fuel cycle. The plants have demonstrated the inherent safety characteristics, the low activation of components, and the high efficiency associated with the HTGR concept. This experience has been translated into the conceptual design of a medium-sized 1170-MW(t) HTGR for generation of 450 MW of electric power. The concept incorporates inherent HTGR safety characteristics (a multiply redundant prestressed concrete reactor vessel (PCRV), a graphite core, and an inert single-phase coolant) and engineered safety features (core auxiliary cooling, relief valve, and steam generator dump systems).

  3. Overview of the EUROfusion Medium Size Tokamak scientific program

    NASA Astrophysics Data System (ADS)

    Martin, Piero; Coda, Stefano; Eich, Thomas; Hakola, Antti; Meyer, Hendrik; EUROfusion MST1 Team; AUG Team; MAST-U Team; TCV Team

    2016-10-01

    The EUROfusion MST (Medium Size Tokamaks) task force is in charge of the European science programme in the ASDEX Upgrade, TCV and MAST-U tokamaks. This paper will present an overview of the main results obtained in the 2015/16 campaign in AUG and TCV and the future plans. We will discuss, among others, successful disruption and runaway electron control experiments with MGI and 3D fields, the achievement of full ELM suppression with RMP accompanied by the understanding of plasma response and the heat load pattern study, the exploration of regimes with impurity seeding at high P/R with 85% radiation fraction and good confinement, the study of tungsten fuzz, where W samples with pre-formed nanostructures were exposed to H-mode Helium plasmas and the investigation on advanced divertor concepts. A survey of MHD limits and of MHD control in standard and high-beta regimes will be presented. The results from the AUG campaign dedicated to He plasmas in support of ITER initial operation will also be presented, as well as analysis of old MAST data that reveal interesting features in the filamentary transport. See http://www.euro-fusionscipub.org/mst1.

  4. Salary Management System for Small and Medium-sized Enterprises

    NASA Astrophysics Data System (ADS)

    Hao, Zhang; Guangli, Xu; Yuhuan, Zhang; Yilong, Lei

    Small and Medium-sized Enterprises (SMEs) in the process of wage entry, calculation, the total number are needed to be done manually in the past, the data volume is quite large, processing speed is low, and it is easy to make error, which is resulting in low efficiency. The main purpose of writing this paper is to present the basis of salary management system, establish a scientific database, the computer payroll system, using the computer instead of a lot of past manual work in order to reduce duplication of staff labor, it will improve working efficiency.This system combines the actual needs of SMEs, through in-depth study and practice of the C/S mode, PowerBuilder10.0 development tools, databases and SQL language, Completed a payroll system needs analysis, database design, application design and development work. Wages, departments, units and personnel database file are included in this system, and have data management, department management, personnel management and other functions, through the control and management of the database query, add, delete, modify, and other functions can be realized. This system is reasonable design, a more complete function, stable operation has been tested to meet the basic needs of the work.

  5. Climatic Effects of Medium-Sized Asteroid Impacts on Land

    NASA Astrophysics Data System (ADS)

    Bardeen, C.; Garcia, R. R.; Toon, O. B.; Otto-Bliesner, B. L.; Wolf, E. T.

    2015-12-01

    Using the Community Earth System Model (CESM), a three-dimensional coupled climate model with interactive chemistry, we have simulated the climate response to a medium-sized (1 km) asteroid impact on the land. An impact of this size would cause local fires and may also generate submicron dust particles. Dust aerosols are injected into the upper atmosphere where they persist for ~3 years. Soot aerosols from fires are injected into the troposphere and absorb solar radiation heating the air which helps loft the soot into the stratosphere where it persists for ~10 years. Initially, these aerosols cause a heating of over 240 K in the stratosphere and up to a 70% reduction in downwelling solar radiation at the surface. Global average surface temperature cools by as much as -8.5 K, ocean temperature cools by -4.5 K, precipitation is reduced by 50%, and the ozone column is reduced by 55%. The surface UV Index exceeds 20 in the tropics for several years. These changes represent a significant hazard to life on a global scale. These results extend the work of Pierazzo et al. (2010), also using CESM, which found a significant impact on stratospheric ozone, but little change in surface temperature or precipitation, from a 1 km asteroid impact in the ocean.

  6. Time-efficient flexible superposition of medium-sized molecules

    NASA Astrophysics Data System (ADS)

    Lemmen, Christian; Lengauer, Thomas

    1997-07-01

    We present an efficient algorithm for the structural alignment of medium-sized organic molecules. The algorithm has been developed for applications in 3D QSAR and in receptor modeling. The method assumes one of the molecules, the reference ligand, to be presented in the conformation that it adopts inside the receptor pocket. The second molecule, the test ligand, is considered to be flexible, and is assumed to be given in an arbitrary low-energy conformation. Ligand flexibility is modeled by decomposing the test ligand into molecular fragments, such that ring systems are completely contained in a single fragment. Conformations of fragments and torsional angles of single bonds are taken from a small finite set, which depends on the fragment and bond, respectively. The algorithm superimposes a distinguished base fragment of the test ligand onto a suitable region of the reference ligand and then attaches the remaining fragments of the test ligand in a step-by-step fashion. During this process, a scoring function is optimized that encompasses bonding terms and terms accounting for steric overlap as well as for similarity of chemical properties of both ligands. The algorithm has been implemented in the FLEXS system. To validate the quality of the produced results, we have selected a number of examples for which the mutual superposition of two ligands is experimentally given by the comparison of the binding geometries known from the crystal structures of their corresponding protein-ligand complexes. On more than two-thirds of the test examples the algorithm produces rms deviations of the predicted versus the observed conformation of the test ligand below 1.5 Å. The run time of the algorithm on a single problem instance is a few minutes on a common-day workstation. The overall goal of this research is to drastically reduce run times, while limiting the inaccuracies of the model and the computation to a tolerable level.

  7. Managers' Understanding of Workplace Health Promotion within Small and Medium-Sized Enterprises: A Phenomenological Study

    ERIC Educational Resources Information Center

    Moore, Ann; Parahoo, Kader; Fleming, Paul

    2011-01-01

    Objective: This study aimed at exploring managers' understanding of workplace health promotion and experiences of workplace health promotion activity within small and medium-sized enterprises. Design: A Heideggerian interpretive phenomenological methodology was adopted. Setting: This study was undertaken with small and medium-sized enterprise…

  8. Design and implementation of web server soft load balancing in small and medium-sized enterprise

    NASA Astrophysics Data System (ADS)

    Yan, Liu

    2011-12-01

    With the expansion of business scale, small and medium-sized enterprises began to use information platform to improve their management and competition ability, the server becomes the core factor which restricts the enterprise's infomationization construction. This paper puts forward a suitable design scheme for small and medium-sized enterprise web server soft load balancing, and proved it effective through experiment.

  9. Dopamine-Induced Changes in Gαolf Protein Levels in Striatonigral and Striatopallidal Medium Spiny Neurons Underlie the Genesis of l-DOPA-Induced Dyskinesia in Parkinsonian Mice

    PubMed Central

    Morigaki, Ryoma; Okita, Shinya; Goto, Satoshi

    2017-01-01

    The dopamine precursor, l-3,4-dihydroxyphenylalanine (l-DOPA), exerts powerful therapeutic effects but eventually generates l-DOPA-induced dyskinesia (LID) in patients with Parkinson’s disease (PD). LID has a close link with deregulation of striatal dopamine/cAMP signaling, which is integrated by medium spiny neurons (MSNs). Olfactory type G-protein α subunit (Gαolf), a stimulatory GTP-binding protein encoded by the GNAL gene, is highly concentrated in the striatum, where it positively couples with dopamine D1 (D1R) receptor and adenosine A2A receptor (A2AR) to increase intracellular cAMP levels in MSNs. In the striatum, D1Rs are mainly expressed in the MSNs that form the striatonigral pathway, while D2Rs and A2ARs are expressed in the MSNs that form the striatopallidal pathway. Here, we examined the association between striatal Gαolf protein levels and the development of LID. We used a hemi-parkinsonian mouse model with nigrostriatal lesions induced by 6-hydroxydopamine (6-OHDA). Using quantitative immunohistochemistry (IHC) and a dual-antigen recognition in situ proximity ligation assay (PLA), we here found that in the dopamine-depleted striatum, there appeared increased and decreased levels of Gαolf protein in striatonigral and striatopallidal MSNs, respectively, after a daily pulsatile administration of l-DOPA. This leads to increased responsiveness to dopamine stimulation in both striatonigral and striatopallidal MSNs. Because Gαolf protein levels serve as a determinant of cAMP signal-dependent activity in striatal MSNs, we suggest that l-DOPA-induced changes in striatal Gαolf levels in the dopamine-depleted striatum could be a key event in generating LID. PMID:28239340

  10. Spiny plants, mammal browsers, and the origin of African savannas

    PubMed Central

    Charles-Dominique, Tristan; Davies, T. Jonathan; Hempson, Gareth P.; Bezeng, Bezeng S.; Kabongo, Ronny M.; Maurin, Olivier; Muasya, A. Muthama; van der Bank, Michelle; Bond, William J.

    2016-01-01

    Savannas first began to spread across Africa during the Miocene. A major hypothesis for explaining this vegetation change is the increase in C4 grasses, promoting fire. We investigated whether mammals could also have contributed to savanna expansion by using spinescence as a marker of mammal herbivory. Looking at the present distribution of 1,852 tree species, we established that spinescence is mainly associated with two functional types of mammals: large browsers and medium-sized mixed feeders. Using a dated phylogeny for the same tree species, we found that spinescence evolved at least 55 times. The diversification of spiny plants occurred long after the evolution of Afrotherian proboscideans and hyracoids. However, it is remarkably congruent with diversification of bovids, the lineage including the antelope that predominantly browse these plants today. Our findings suggest that herbivore-adapted savannas evolved several million years before fire-maintained savannas and probably, in different environmental conditions. Spiny savannas with abundant mammal herbivores occur in drier climates and on nutrient-rich soils, whereas fire-maintained savannas occur in wetter climates on nutrient-poor soils. PMID:27601649

  11. Spiny plants, mammal browsers, and the origin of African savannas.

    PubMed

    Charles-Dominique, Tristan; Davies, T Jonathan; Hempson, Gareth P; Bezeng, Bezeng S; Daru, Barnabas H; Kabongo, Ronny M; Maurin, Olivier; Muasya, A Muthama; van der Bank, Michelle; Bond, William J

    2016-09-20

    Savannas first began to spread across Africa during the Miocene. A major hypothesis for explaining this vegetation change is the increase in C4 grasses, promoting fire. We investigated whether mammals could also have contributed to savanna expansion by using spinescence as a marker of mammal herbivory. Looking at the present distribution of 1,852 tree species, we established that spinescence is mainly associated with two functional types of mammals: large browsers and medium-sized mixed feeders. Using a dated phylogeny for the same tree species, we found that spinescence evolved at least 55 times. The diversification of spiny plants occurred long after the evolution of Afrotherian proboscideans and hyracoids. However, it is remarkably congruent with diversification of bovids, the lineage including the antelope that predominantly browse these plants today. Our findings suggest that herbivore-adapted savannas evolved several million years before fire-maintained savannas and probably, in different environmental conditions. Spiny savannas with abundant mammal herbivores occur in drier climates and on nutrient-rich soils, whereas fire-maintained savannas occur in wetter climates on nutrient-poor soils.

  12. 40 CFR 428.60 - Applicability; description of the medium-sized general molded, extruded, and fabricated rubber...

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... medium-sized general molded, extruded, and fabricated rubber plants subcategory. 428.60 Section 428.60... RUBBER MANUFACTURING POINT SOURCE CATEGORY Medium-Sized General Molded, Extruded, and Fabricated Rubber Plants Subcategory § 428.60 Applicability; description of the medium-sized general molded, extruded,...

  13. 40 CFR 428.60 - Applicability; description of the medium-sized general molded, extruded, and fabricated rubber...

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... medium-sized general molded, extruded, and fabricated rubber plants subcategory. 428.60 Section 428.60... (CONTINUED) RUBBER MANUFACTURING POINT SOURCE CATEGORY Medium-Sized General Molded, Extruded, and Fabricated Rubber Plants Subcategory § 428.60 Applicability; description of the medium-sized general...

  14. 40 CFR 428.60 - Applicability; description of the medium-sized general molded, extruded, and fabricated rubber...

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... medium-sized general molded, extruded, and fabricated rubber plants subcategory. 428.60 Section 428.60... (CONTINUED) RUBBER MANUFACTURING POINT SOURCE CATEGORY Medium-Sized General Molded, Extruded, and Fabricated Rubber Plants Subcategory § 428.60 Applicability; description of the medium-sized general...

  15. 40 CFR 428.60 - Applicability; description of the medium-sized general molded, extruded, and fabricated rubber...

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... medium-sized general molded, extruded, and fabricated rubber plants subcategory. 428.60 Section 428.60... (CONTINUED) RUBBER MANUFACTURING POINT SOURCE CATEGORY Medium-Sized General Molded, Extruded, and Fabricated Rubber Plants Subcategory § 428.60 Applicability; description of the medium-sized general...

  16. The cytoarchitectonic and neuronal structure of the red nucleus in guinea pig: Nissl and Golgi studies.

    PubMed

    Robak, A; Szteyn, S; Bogus-Nowakowska, K; Doboszyńska, T; Równiak, M

    2000-01-01

    The present studies were carried out on the brains of adult guinea pigs, Dunkin-Hartley strain. On the basis of preparations, they were stained according to the Nissl and the Klüver-Barrera method's; a short description of the cytoarchitectonics and the characteristics of the rubral cells were written. The red nucleus (RN) of the guinea pig is 1.2 mm in length. Three cellular parts in RN, and three classes (A, B, C) of the rubral cells were distinguished. Taking into consideration the predominant cell size, RN was divided into magnocellular part (RNm), parvocellular part (RNp) and intermediate part (RNi). On the basis of Golgi impregnated preparations four neuronal types (I, II, III, IV) were distinguished. To sum up, in the guinea pig were observed: the large, mainly multipolar (type I) and bipolar (type II) spiny being coarse (class A) in Nissl material; the medium-sized, triangular, aspiny (type III) corresponding to the fine cells (class B); and the small, both spiny and aspiny neurons (type IV), which are the fine or achromatic cells (classes B or C) in Nissl stained slices. The highest degree of dendritic branching was observed in type I, whereas the lowest in cells of types III and IV.

  17. Planning an Authority Control Project at a Medium-Sized University Library.

    ERIC Educational Resources Information Center

    Zhang, Sha Li

    2001-01-01

    Authority control is a vital part of providing students and faculty with adequate access to collections in university libraries. Small and medium-sized libraries find it challenging to meet rising user expectations and provide adequate access in an online environment through appropriate authority work. A planning process is offered on an authority…

  18. Key Influencing Factors behind Moodle Adoption in Irish Small to Medium Sized Higher Education Colleges

    ERIC Educational Resources Information Center

    Walker, David; Livadas, Lelia; Miles, Gail

    2011-01-01

    This research investigated Irish Small to Medium Sized Educational Institutions (SMSEs) involved in Higher Education (HE) that adopted Moodle, the OSS (Open Source Software) course management system (CMS). As Moodle has only been adopted in the Irish HE sector in the last 5-7 years, this research crucially studied the attitudes of the SMSEs that…

  19. Supporting the E-Business Readiness of Small and Medium-Sized Enterprises: Approaches and Metrics.

    ERIC Educational Resources Information Center

    Jutla, Dawn; Bodorik, Peter; Dhaliwal, Jasbir

    2002-01-01

    Presents a conceptual model for governments in creating a climate that facilitates the national adoption of e-business. Focuses on the needs of small and medium-sized enterprises, suggests measures to assess how a country is performing in providing a positive e-business climate, and provides examples from Canada, The Netherlands, Norway, and…

  20. Toward a Singleton Undergraduate Computer Graphics Course in Small and Medium-Sized Colleges

    ERIC Educational Resources Information Center

    Shesh, Amit

    2013-01-01

    This article discusses the evolution of a single undergraduate computer graphics course over five semesters, driven by a primary question: if one could offer only one undergraduate course in graphics, what would it include? This constraint is relevant to many small and medium-sized colleges that lack resources, adequate expertise, and enrollment…

  1. Small and Medium-Sized Information Technology Firms: Assessment of Non-Local Partnership Facilitators

    ERIC Educational Resources Information Center

    Findikoglu, Melike Nur

    2012-01-01

    A two-phased qualitative study was conducted to explore the facilitators of non-local (i.e. domestic or international) partnerships formed by small- and medium-sized firms (SME). Rooted in trust, proximity and dynamic capabilities lenses, the study focused on behaviors of SMEs performing in dynamic, competitive and highly interlinked industry, the…

  2. A Bare Bones Reference Collection for Small and Medium-Sized Public Libraries in Maine.

    ERIC Educational Resources Information Center

    Southern Maine Library District, Portland.

    This reference list was compiled to offer Maine librarians who serve communities with the resources of small- or medium-sized libraries a starting point to assess their reference collections for breadth and depth. Initially based on a list distributed by the Vermont Department of Libraries in 1987, this guide evaluates reference materials on the…

  3. Business Continuity Planning Resources for Small- and Medium-Sized Businesses

    SciTech Connect

    Judd, Kathleen S.; Lesperance, Ann M.

    2010-05-14

    This document/memo summarizes existing resources and guidance on business continuity planning for small- to medium-sized businesses. DTRA will share this information with large commercial businesses who identified the need to help their suppliers and other key collaborators prepare business continuity plans in order to speed recovery from a wide-area bioterrorism incident.

  4. An Agile Methodology for Implementing Service-Oriented Architecture in Small and Medium Sized Organizations

    ERIC Educational Resources Information Center

    Laidlaw, Gregory

    2013-01-01

    The purpose of this study is to evaluate the use of Lean/Agile principles, using action research to develop and deploy new technology for Small and Medium sized enterprises. The research case was conducted at the Lapeer County Sheriff's Department and involves the initial deployment of a Service Oriented Architecture to alleviate the data…

  5. Successful E-Learning in Small and Medium-Sized Enterprises

    ERIC Educational Resources Information Center

    Paulsen, Morten Flate

    2009-01-01

    So far, e-learning has primarily been used when there are many learners involved. The up-front investments related to e-learning are relatively high, and may be perceived as prohibitive for small and medium-sized enterprises (SMEs). Some e-learning is, however, getting less expensive, and some e-learning models are more suited for small-scale…

  6. Current information technology needs of small to medium sized apparel manufacturers and contractors

    SciTech Connect

    Wipple, C.; Vosti, E.

    1997-11-01

    This report documents recent efforts of the American Textile Partnership (AMTEX) Demand Activated Manufacturing Architecture (DAMA) Project to address needs that are characterized of small to medium sized apparel manufactures and contractors. Background on the AMTEX/DAMA project and objectives for this specific efforts are discussed.

  7. Barriers to Employee Training in Small and Medium Sized Enterprises: Insights and Evidences from Mauritius

    ERIC Educational Resources Information Center

    Padachi, Kesseven; Bhiwajee, Soolakshna Lukea

    2016-01-01

    Purpose: Training is an important component of successful business concerns. However, although there is growing acceptance amongst scholars that small- and medium-sized enterprises (SMEs) are engines that drive economies across nations, through their contribution in terms of job creation and poverty reduction; extant research portray that these…

  8. Sustainability and Small to Medium Sized Enterprises--How to Engage Them

    ERIC Educational Resources Information Center

    Condon, Linda

    2004-01-01

    Small and medium sized enterprises (SMEs) have a major advantage over larger organisations in regard to addressing sustainability issues--their size means they are able to react very quickly to changes in the business environment. They are disadvantaged, however, by lack of information on marketplace changes that make sustainability an opportunity…

  9. [Types of neurons in the visual cortex of the rat, identified in Nissl- and deimpregnated Golgi preparations].

    PubMed

    Werner, L; Hedlich, A; Winkelmann, E

    1985-01-01

    Neuronal types of the rat's visual cortex were identified in Nissl stained and deimpregnated Golgi sections (rapid Golgi method modified by Fairén et al. 1977, Golgi-Bubenaite, Golgi-Kopsch and modified by Braitenberg; deimpregnation after FAIREN et al. 1977 and Braak and Braak 1982, respectively). Cytoplasm and nucleus become visible in deimpregnated neurons and can then be counter-stained with methylene blue or toluidin blue. Somal and nuclear features of Nissl stained and deimpregnated neurons were compared. Provided that these features as well as the specific localization, the relative size and the shape of the soma agree the neurons are identical. We could find that the following neuronal types are identical in Golgi and Nissl stained sections: pyramidal cells of layers II-VI, pyramid-like neurons of layers VI and VII (VIa, b, c) (type C, Werner et al. 1982), multiangular neurons of layer I (type A, Werner et al. 1982), spiny stellate cells of layer IV, sparsely spined neurons with ascending axons (Martinotti cells) (type H, Werner et al. 1982), large and medium-sized spine-free, multipolar neurons (basket cells) (type B, Werner et al. 1982). Bipolar neurons and chandelier cells are identical with neurons poor in cytoplasm (types E, F, G, Werner et al. 1982). Until today two neuronal types could not be identified: type D of L I (Werner et al. 1982) and small, sparsely-spined neurons of layer IV with variable axons (Hedlich and Winkelmann 1982; Hedlich et al. 1984). Characteristics of somata, dendrites and axons of neurons identified in this paper are summarized in table 1. In most cases, these findings confirm earlier suppositions concerning the identity of neuronal types of the rat's visual cortex in Golgi and Nissl stained sections (Werner et al. 1979) and verify the values of their frequency and distribution pattern (Werner et al. 1982).

  10. Teaching Medium-Sized ERP Systems - A Problem-Based Learning Approach

    NASA Astrophysics Data System (ADS)

    Winkelmann, Axel; Matzner, Martin

    In order to increase the diversity in IS education, we discuss an approach for teaching medium-sized ERP systems in master courses. Many of today's IS curricula are biased toward large ERP packages. Nevertheless, these ERP systems are only a part of the ERP market. Hence, this chapter describes a course outline for a course on medium-sized ERP systems. Students had to study, analyze, and compare five different ERP systems during a semester. The chapter introduces a procedure model and scenario for setting up similar courses at other universities. Furthermore, it describes some of the students' outcomes and evaluates the contribution of the course with regard to a practical but also academic IS education.

  11. Analysis of energy-efficiency investment decisions by small and medium-sized manufacturers

    SciTech Connect

    Woodruff, M.G.; Roop, J.M.; Seely, H.E.; Muller, M.R.; Jones, T.W.; Dowd, J.

    1996-05-01

    This report highlights the results of a comprehensive analysis of investment decisions regarding energy-efficiency measures at small and medium-sized manufacturing plants. The analysis is based on the experiences of companies participating in the DOE Industrial Assessment Center (IAC) program. The IAC program is a network of university-based centers that provides energy and waste assessments to small and medium-sized manufacturing plants. The purposes of this report are to do the following: (1) Examine what the data collected reveal about patterns of implementation of recommended energy- efficiency measures, (2) Evaluate how various factors, such as the type of industry, the characteristics of the manufacturing plants, or the cost of the measures, appear to effect implementation rates, (3) Examine reasons why recommended energy-saving measures are accepted or rejected.

  12. Asymmetric Synthesis of Medium-Sized Rings by Intramolecular Au(I)-Catalyzed Cyclopropanation

    PubMed Central

    Watson, Iain D. G.; Ritter, Stefanie; Toste, F. Dean

    2009-01-01

    An efficient method for the asymmetric gold(I)-catalyzed preparation of medium sized rings has been developed. The method provides 7- to 9-membered rings in excellent yield. High enantioselectivities can be achieved for 7- and 8-membered ring products employing chiral gold(I) complexes. The results provide insight into the mechanism, showing the fluxional nature of gold(I)-stabilized vinyl carbenoid intermediates. PMID:19161306

  13. Small- and Medium-Sized Commercial Building Monitoring and Controls Needs: A Scoping Study

    SciTech Connect

    Katipamula, Srinivas; Underhill, Ronald M.; Goddard, James K.; Taasevigen, Danny J.; Piette, M. A.; Granderson, J.; Brown, Rich E.; Lanzisera, Steven M.; Kuruganti, T.

    2012-10-31

    Buildings consume over 40% of the total energy consumption in the U.S. A significant portion of the energy consumed in buildings is wasted because of the lack of controls or the inability to use existing building automation systems (BASs) properly. Much of the waste occurs because of our inability to manage and controls buildings efficiently. Over 90% of the buildings are either small-size (<5,000 sf) or medium-size (between 5,000 sf and 50,000 sf); these buildings currently do not use BASs to monitor and control their building systems from a central location. According to Commercial Building Energy Consumption Survey (CBECS), about 10% of the buildings in the U.S. use BASs or central controls to manage their building system operations. Buildings that use BASs are typically large (>100,000 sf). Lawrence Berkeley National Laboratory (LBNL), Oak Ridge National Laboratory (ORNL) and Pacific Northwest National Laboratory (PNNL) were asked by the U.S. Department of Energy’s (DOE’s) Building Technologies Program (BTP) to identify monitoring and control needs for small- and medium-sized commercial buildings and recommend possible solutions. This study documents the needs and solutions for small- and medium-sized buildings.

  14. Consultant-Client Relationship and Knowledge Transfer in Small- and Medium-Sized Enterprises Change Processes.

    PubMed

    Martinez, Luis F; Ferreira, Aristides I; Can, Amina B

    2016-04-01

    Based on Szulanski's knowledge transfer model, this study examined how the communicational, motivational, and sharing of understanding variables influenced knowledge transfer and change processes in small- and medium-sized enterprises, particularly under projects developed by funded programs. The sample comprised 144 entrepreneurs, mostly male (65.3%) and mostly ages 35 to 45 years (40.3%), who filled an online questionnaire measuring the variables of "sharing of understanding," "motivation," "communication encoding competencies," "source credibility," "knowledge transfer," and "organizational change." Data were collected between 2011 and 2012 and measured the relationship between clients and consultants working in a Portuguese small- and medium-sized enterprise-oriented action learning program. To test the hypotheses, structural equation modeling was conducted to identify the antecedents of sharing of understanding, motivational, and communicational variables, which were positively correlated with the knowledge transfer between consultants and clients. This transfer was also positively correlated with organizational change. Overall, the study provides important considerations for practitioners and academicians and establishes new avenues for future studies concerning the issues of consultant-client relationship and the efficacy of Government-funded programs designed to improve performance of small- and medium-sized enterprises.

  15. 50 CFR 648.232 - Spiny dogfish specifications.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 50 Wildlife and Fisheries 12 2012-10-01 2012-10-01 false Spiny dogfish specifications. 648.232... Measures for the Spiny Dogfish Fishery § 648.232 Spiny dogfish specifications. (a) Commercial quota and other specification measures. The Spiny Dogfish Monitoring Committee shall recommend to the Joint...

  16. 50 CFR 648.232 - Spiny dogfish specifications.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 50 Wildlife and Fisheries 10 2011-10-01 2011-10-01 false Spiny dogfish specifications. 648.232... Measures for the Spiny Dogfish Fishery § 648.232 Spiny dogfish specifications. (a) Commercial quota and other specification measures. The Spiny Dogfish Monitoring Committee shall recommend to the Joint...

  17. 50 CFR 648.233 - Spiny dogfish Accountability Measures (AMs).

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 50 Wildlife and Fisheries 12 2014-10-01 2014-10-01 false Spiny dogfish Accountability Measures... Management Measures for the Spiny Dogfish Fishery § 648.233 Spiny dogfish Accountability Measures (AMs). (a... quota described in § 648.232 will be harvested and shall close the EEZ to fishing for spiny dogfish...

  18. 50 CFR 648.232 - Spiny dogfish specifications.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 50 Wildlife and Fisheries 12 2013-10-01 2013-10-01 false Spiny dogfish specifications. 648.232... Measures for the Spiny Dogfish Fishery § 648.232 Spiny dogfish specifications. (a) Commercial quota and other specification measures. The Spiny Dogfish Monitoring Committee shall recommend to the Joint...

  19. 50 CFR 648.232 - Spiny dogfish specifications.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 50 Wildlife and Fisheries 12 2014-10-01 2014-10-01 false Spiny dogfish specifications. 648.232... Measures for the Spiny Dogfish Fishery § 648.232 Spiny dogfish specifications. (a) Commercial quota and other specification measures. The Spiny Dogfish Monitoring Committee shall recommend to the Joint...

  20. 50 CFR 622.458 - Caribbean spiny lobster import prohibitions.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 50 Wildlife and Fisheries 12 2013-10-01 2013-10-01 false Caribbean spiny lobster import..., AND SOUTH ATLANTIC Spiny Lobster Fishery of Puerto Rico and the U.S. Virgin Islands § 622.458 Caribbean spiny lobster import prohibitions. (a) Minimum size limits for imported spiny lobster. There...

  1. 50 CFR 622.409 - Spiny lobster import prohibitions.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 50 Wildlife and Fisheries 12 2014-10-01 2014-10-01 false Spiny lobster import prohibitions. 622... ATLANTIC Spiny Lobster Fishery of the Gulf of Mexico and South Atlantic § 622.409 Spiny lobster import prohibitions. (a) Minimum size limits for imported spiny lobster. There are two minimum size limits that...

  2. 50 CFR 622.455 - Landing spiny lobster intact.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 50 Wildlife and Fisheries 12 2014-10-01 2014-10-01 false Landing spiny lobster intact. 622.455... ATLANTIC Spiny Lobster Fishery of Puerto Rico and the U.S. Virgin Islands § 622.455 Landing spiny lobster intact. (a) A Caribbean spiny lobster in or from the Caribbean EEZ must be maintained with head...

  3. 50 CFR 622.455 - Landing spiny lobster intact.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 50 Wildlife and Fisheries 12 2013-10-01 2013-10-01 false Landing spiny lobster intact. 622.455... ATLANTIC Spiny Lobster Fishery of Puerto Rico and the U.S. Virgin Islands § 622.455 Landing spiny lobster intact. (a) A Caribbean spiny lobster in or from the Caribbean EEZ must be maintained with head...

  4. 50 CFR 622.409 - Spiny lobster import prohibitions.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 50 Wildlife and Fisheries 12 2013-10-01 2013-10-01 false Spiny lobster import prohibitions. 622... ATLANTIC Spiny Lobster Fishery of the Gulf of Mexico and South Atlantic § 622.409 Spiny lobster import prohibitions. (a) Minimum size limits for imported spiny lobster. There are two minimum size limits that...

  5. 50 CFR 622.458 - Caribbean spiny lobster import prohibitions.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 50 Wildlife and Fisheries 12 2014-10-01 2014-10-01 false Caribbean spiny lobster import..., AND SOUTH ATLANTIC Spiny Lobster Fishery of Puerto Rico and the U.S. Virgin Islands § 622.458 Caribbean spiny lobster import prohibitions. (a) Minimum size limits for imported spiny lobster. There...

  6. 75 FR 9431 - Small and Medium-Sized Enterprises: U.S. and EU Export Activities, and Barriers and Opportunities...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-03-02

    ... From the Federal Register Online via the Government Publishing Office INTERNATIONAL TRADE COMMISSION Small and Medium-Sized Enterprises: U.S. and EU Export Activities, and Barriers and Opportunities... investigations, investigation No. 332-509, Small and Medium-Sized Enterprises: U.S. and EU Export Activities,...

  7. 40 CFR 428.60 - Applicability; description of the medium-sized general molded, extruded, and fabricated rubber...

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... medium-sized general molded, extruded, and fabricated rubber plants subcategory. 428.60 Section 428.60... RUBBER MANUFACTURING POINT SOURCE CATEGORY Medium-Sized General Molded, Extruded, and Fabricated Rubber... fabricated rubber plants subcategory. The following provisions of this subpart are applicable to...

  8. Preliminary Design Study of Medium Sized Gas Cooled Fast Reactor with Natural Uranium as Fuel Cycle Input

    NASA Astrophysics Data System (ADS)

    Meriyanti, Su'ud, Zaki; Rijal, K.; Zuhair, Ferhat, A.; Sekimoto, H.

    2010-06-01

    In this study a fesibility design study of medium sized (1000 MWt) gas cooled fast reactors which can utilize natural uranium as fuel cycle input has been conducted. Gas Cooled Fast Reactor (GFR) is among six types of Generation IV Nuclear Power Plants. GFR with its hard neuron spectrum is superior for closed fuel cycle, and its ability to be operated in high temperature (850° C) makes various options of utilizations become possible. To obtain the capability of consuming natural uranium as fuel cycle input, modified CANDLE burn-up scheme[1-6] is adopted this GFR system by dividing the core into 10 parts of equal volume axially. Due to the limitation of thermal hydraulic aspects, the average power density of the proposed design is selected about 70 W/cc. As an optimization results, a design of 1000 MWt reactors which can be operated 10 years without refueling and fuel shuffling and just need natural uranium as fuel cycle input is discussed. The average discharge burn-up is about 280 GWd/ton HM. Enough margin for criticallity was obtained for this reactor.

  9. A 10-step safety management framework for construction small and medium-sized enterprises.

    PubMed

    Gunduz, Murat; Laitinen, Heikki

    2016-07-20

    It is of great importance to develop an occupational health and safety management system (OHS MS) to form a systemized approach to improve health and safety. It is a known fact that thousands of accidents and injuries occur in the construction industry. Most of these accidents occur in small and medium-sized enterprises (SMEs). This article provides a 10-step user-friendly OHS MS for the construction industry. A quantitative OHS MS indexing method is also introduced in the article. The practical application of the system to real SMEs and its promising results are also presented.

  10. Detection of Medium-Sized Polycyclic Aromatic Hydrocarbons via Fluorescence Energy Transfer

    PubMed Central

    Serio, Nicole; Prignano, Lindsey; Peters, Sean; Levine, Mindy

    2015-01-01

    Reported herein is the use of proximity-induced non-covalent energy transfer for the detection of medium-sized polycyclic aromatic hydrocarbons (PAHs). This energy transfer occurs within the cavity of γ-cyclodextrin in various aqueous environments, including human plasma and coconut water. Highly efficient energy transfer was observed, and the efficiency of the energy transfer is independent of the concentration of γ-cyclodextrin used, demonstrating the importance of hydrophobic binding in facilitating such energy transfer. Low limits of detection were also observed for many of the PAHs investigated, which is promising for the development of fluorescence-based detection schemes. PMID:25821390

  11. Occupational safety and health in small and medium-sized enterprises during social and economic transformation.

    PubMed

    Koradecka, D

    2001-01-01

    Small and medium-sized enterprises (SMEs) in Central and Eastern Europe at the turn of the 1980s and 1990s were characterised by many people exposed to hazardous working conditions. Statistics recorded a considerable increase in the number of occupational diseases. They also showed that it was more dangerous to work for a small company. The transition from planned to market economy has brought about an increase in the number of SMEs in Poland. Data on them are provided. The role of the Central Institute for Labour Protection in studying SMEs is presented. A pilot study of employers and employees is discussed.

  12. Bank Size and Small- and Medium-sized Enterprise (SME) Lending: Evidence from China.

    PubMed

    Shen, Yan; Shen, Minggao; Xu, Zhong; Bai, Ying

    2009-04-01

    Using panel data collected in 2005, we evaluate how bank size, discretion over credit, incentive schemes, competition, and the institutional environment affect lending to small- and medium-sized enterprises in China. We deal with the endogeneity problem using instrumental variables, and a reduced-form approach is also applied to allow for weak instruments in estimation. We find that total bank asset is an insignificant factor for banks' decision on small- and medium-enterprise (SME) lending, but more local lending authority, more competition, carefully designed incentive schemes, and stronger law enforcement encourage commercial banks to lend to SMEs.

  13. Identification of Medium-Sized Copy Number Alterations in Whole-Genome Sequencing

    PubMed Central

    Ozer, Hatice Gulcin; Usubalieva, Aisulu; Dorrance, Adrienne; Yilmaz, Ayse Selen; Caligiuri, Michael; Marcucci, Guido; Huang, Kun

    2014-01-01

    The genome-wide discoveries such as detection of copy number alterations (CNA) from high-throughput whole-genome sequencing data enabled new developments in personalized medicine. The CNAs have been reported to be associated with various diseases and cancers including acute myeloid leukemia. However, there are multiple challenges to the use of current CNA detection tools that lead to high false-positive rates and thus impede widespread use of such tools in cancer research. In this paper, we discuss these issues and propose possible solutions. First, since the entire genome cannot be mapped due to some regions lacking sequence uniqueness, current methods cannot be appropriately adjusted to handle these regions in the analyses. Thus, detection of medium-sized CNAs is also being directly affected by these mappability problems. The requirement for matching control samples is also an important limitation because acquiring matching controls might not be possible or might not be cost efficient. Here we present an approach that addresses these issues and detects medium-sized CNAs in cancer genomes by (1) masking unmappable regions during the initial CNA detection phase, (2) using pool of a few normal samples as control, and (3) employing median filtering to adjust CNA ratios to its surrounding coverage and eliminate false positives. PMID:25788829

  14. Biotransformation in Egyptian spiny mouse Acomys cahirinus.

    PubMed

    Watkins, J B; LaFollette, J W; Sanders, R A

    1995-01-01

    The activities of several representative biotransformation enzymes were determined in male and female spiny mouse tissues. Cytochrome P450 monooxygenase activity toward benzo(a)pyrene was significantly greater in female spiny mouse intestine than in males. Activity toward benzphetamine in both sexes was high in the liver, with little activity in the kidney and intestine. Sulfotransferase activity was high in kidney and intestine of female spiny mice but undetectable in the same tissues in males. Hepatic glutathione S-transferase activity towards 1-chloro-2,4-dinitrobenzene in females was significantly higher than in males. UDP-Glucuronosyltransferase activity toward 1-naphthol in both sexes in the kidney was significantly higher than hepatic and intestinal activity. Intestinal N-acetyltransferase activity towards 2-aminofluorene and beta-naphthylamine was significantly greater in females than males. No consistent relation appeared to exist between biotransformation activities in spiny mouse and those in other related rodent species.

  15. Innovation Gateways for SMEs: Finding the Formula for Successful Interaction between Universities and Small and Medium-Size Firms.

    ERIC Educational Resources Information Center

    Davies, Peter T.

    1995-01-01

    The University of Warwick's Breakthrough Technologies program links with small and medium-sized businesses to stimulate awareness of innovations. The Manufacturing Excellence Initiative provides postgraduate training for company staff that focuses on best practices and change management. (SK)

  16. Selecting Sustainability Indicators for Small to Medium Sized Urban Water Systems Using Fuzzy-ELECTRE.

    PubMed

    Chhipi-Shrestha, Gyan; Hewage, Kasun; Sadiq, Rehan

    2017-03-01

      Urban water systems (UWSs) are challenged by the sustainability perspective. Certain limitations of the sustainability of centralized UWSs and decentralized household level wastewater treatments can be overcome by managing UWSs at an intermediate scale, referred to as small to medium sized UWSs (SMUWSs). SMUWSs are different from large UWSs, mainly in terms of smaller infrastructure, data limitation, smaller service area, and institutional limitations. Moreover, sustainability assessment systems to evaluate the sustainability of an entire UWS are very limited and confined only to large UWSs. This research addressed the gap and has developed a set of 38 applied sustainability performance indicators (SPIs) by using fuzzy-Elimination and Choice Translating Reality (ELECTRE) I outranking method to assess the sustainability of SMUWSs. The developed set of SPIs can be applied to existing and new SMUWSs and also provides a flexibility to include additional SPIs in the future based on the same selection criteria.

  17. In-beam evaluation of a medium-size Resistive-Plate WELL gaseous particle detector

    NASA Astrophysics Data System (ADS)

    Moleri, L.; Amaro, F. D.; Arazi, L.; Azevedo, C. D. R.; Breskin, A.; Coimbra, A. E. C.; Oliveri, E.; Pereira, F. A.; Shaked Renous, D.; Schaarschmidt, J.; dos Santos, J. M. F.; Veloso, J. F. C. A.; Bressler, S.

    2016-09-01

    In-beam evaluation of a fully-equipped medium-size 30 × 30 cm2 Resistive Plate WELL (RPWELL) detector is presented. It consists here of a single element gas-avalanche multiplier with Semitron ESD225 resistive plate, 1 cm2 readout pads and APV25/SRS electronics. Similarly to previous results with small detector prototypes, stable operation at high detection efficiency (> 98%) and low average pad multiplicity (~ 1.2) were recorded with 150 GeV muon and high-rate pion beams, in Ne/(5%CH4), Ar/(5%CH4) and Ar/(7%CO2). This is an important step towards the realization of robust detectors suitable for applications requiring large-area coverage; among them Digital Hadron Calorimetry.

  18. Energy performance of medium-sized healthcare buildings in Victoria, Australia- a case study.

    PubMed

    Rajagopalan, Priyadarsini; Elkadi, Hisham

    2014-01-01

    This paper investigates the energy performance of three medium-sized healthcare buildings in Victoria, Australia, that operate only during the daytime. The aim is to provide preliminary understanding of energy consumption in this particular typology in Australia in relation to the available benchmarks. This paper also identifies the differences of energy consumption between different functional areas within medium health facilities. Building features and operational characteristics contributing to the variations in healthcare energy performance are discussed. The total annual energy consumption data ranging from 167-306 kWh/m(2) or 42-72 kWh/m(3) were compared against international data from various climatic zones. Some of the drivers of energy consumption were determined and potentials for energy and water conservation were identified. Comparison with international standards shows a possibility to achieve lower energy consumption in Victorian healthcare buildings.

  19. Current information technology needs of small to medium sized apparel manufacturers and contractors

    SciTech Connect

    Wimple, C., LLNL

    1998-04-01

    This report documents recent efforts of the American Textile Partnership (AMTEX{sup TM}) Demand Activated Manufacturing Architecture (DAMA) Project to identify opportunities for cost effective enhanced information technology use by small to medium sized apparel manufacturers and contractors. Background on the AMTEX/DAMA project and objectives for the specific DAMA Small and Medium Enterprise (SME) effort are discussed in this section. The approach used to gather information about current opportunities or needs is outlined in Section 2 Approach, and relevant findings are identified and a brief analysis of the information gathered is presented in Section 3 Findings. Recommendations based on the analysis, are offered in Section 4 Recommendations, and plans are suggested for DAMA follow-on in Section 5 Future Plans. Trip reports for each of the companies visited are contained in Appendix E - Company Trip Reports. These individual reports contain the data upon which the analysis presented in Section 3 Findings is based.

  20. Melting Properties of Medium-Sized Silicon Nanoclusters: A Molecular Dynamics Study

    NASA Astrophysics Data System (ADS)

    Li, Haipeng; Xu, Runfeng; Bi, Zetong; Shen, Xiaopeng; Han, Kui

    2016-11-01

    The structures and melting properties of the medium-sized silicon nanoclusters have been comparatively studied using the molecular dynamics method. Structural and thermodynamic parameters are used to characterize the melting properties of the clusters. The size dependence of the melting temperature of silicon nanoclusters is determined using the computation results. Different from the homogeneous melting of bulk silicon, melting of silicon nanoparticles proceeds over a finite temperature range due to surface effects, which shows the heterogeneous melting of nanoclusters. We found that the melting starts at the cluster surface and progressively shifts into the core region. This study provides a fundamental perspective on the melting behaviors of semiconductor silicon nanoclusters at the atomistic level.

  1. IT Governance Practices in Small and Medium-Sized Enterprises: Recommendations from an Empirical Study

    NASA Astrophysics Data System (ADS)

    Huang, Rui; Zmud, Robert W.; Price, R. Leon

    Much has been learned through IT governance research about the nature of IT-related decisions, the location of decision rights for these decisions, and governance mechanisms applied to facilitate associated decision processes in large organisations. Our knowledge about IT governance structures in small and medium-sized enterprises (SME), on the other hand, is quite limited. Adopting a qualitative and inductive approach, this study examines the nature and influence of IT governance in SMEs through interviews with executives from three SMEs. Our results demonstrate that IT decision authority was centralized in all three SMEs but that senior management involvement in governance procedures and communication practices about governance policies were observed to explain differences in these organisations’ IT use. We propose recommendations based on the findings of this study.

  2. Glass formability in medium-sized molecular systems/pharmaceuticals. I. Thermodynamics vs. kinetics

    NASA Astrophysics Data System (ADS)

    Tu, Wenkang; Li, Xiangqian; Chen, Zeming; Liu, Ying Dan; Labardi, Massimiliano; Capaccioli, Simone; Paluch, M.; Wang, Li-Min

    2016-05-01

    Scrutinizing critical thermodynamic and kinetic factors for glass formation and the glass stability of materials would benefit the screening of the glass formers for the industry of glassy materials. The present work aims at elucidating the factors that contribute to the glass formation by investigating medium-sized molecules of pharmaceuticals. Glass transition related thermodynamics and kinetics are performed on the pharmaceuticals using calorimetric, dielectric, and viscosity measurements. The characteristic thermodynamic and kinetic parameters of glass transition are found to reproduce the relations established for small-molecule glass formers. The systematic comparison of the thermodynamic and kinetic contributions to glass formation reveals that the melting-point viscosity is the crucial quantity for the glass formation. Of more interest is the finding of a rough correlation between the melting-point viscosity and the entropy of fusion normalized by the number of beads of the pharmaceuticals, suggesting the thermodynamics can partly manifest its contribution to glass formation via kinetics.

  3. Glass formability in medium-sized molecular systems/pharmaceuticals. I. Thermodynamics vs. kinetics.

    PubMed

    Tu, Wenkang; Li, Xiangqian; Chen, Zeming; Liu, Ying Dan; Labardi, Massimiliano; Capaccioli, Simone; Paluch, M; Wang, Li-Min

    2016-05-07

    Scrutinizing critical thermodynamic and kinetic factors for glass formation and the glass stability of materials would benefit the screening of the glass formers for the industry of glassy materials. The present work aims at elucidating the factors that contribute to the glass formation by investigating medium-sized molecules of pharmaceuticals. Glass transition related thermodynamics and kinetics are performed on the pharmaceuticals using calorimetric, dielectric, and viscosity measurements. The characteristic thermodynamic and kinetic parameters of glass transition are found to reproduce the relations established for small-molecule glass formers. The systematic comparison of the thermodynamic and kinetic contributions to glass formation reveals that the melting-point viscosity is the crucial quantity for the glass formation. Of more interest is the finding of a rough correlation between the melting-point viscosity and the entropy of fusion normalized by the number of beads of the pharmaceuticals, suggesting the thermodynamics can partly manifest its contribution to glass formation via kinetics.

  4. Software-Defined Solutions for Managing Energy Use in Small to Medium Sized Commercial Buildings

    SciTech Connect

    Peffer, Therese; Blumstein, Carl; Culler, David; Modera, Mark; Meier, Alan

    2015-09-10

    The Project uses state-of-the-art computer science to extend the benefits of Building Automation Systems (BAS) typically found in large buildings (>100,000 square foot) to medium-sized commercial buildings (<50,000 sq ft). The BAS developed in this project, termed OpenBAS, uses an open-source and open software architecture platform, user interface, and plug-and-play control devices to facilitate adoption of energy efficiency strategies in the commercial building sector throughout the United States. At the heart of this “turn key” BAS is the platform with three types of controllers—thermostat, lighting controller, and general controller—that are easily “discovered” by the platform in a plug-and-play fashion. The user interface showcases the platform and provides the control system set-up, system status display and means of automatically mapping the control points in the system.

  5. Toward the construction of a medium size prototype Schwarzschild-Couder telescope for CTA

    NASA Astrophysics Data System (ADS)

    Rousselle, J.; Byrum, K.; Cameron, R.; Connaughton, V.; Errando, M.; Griffiths, S.; Guarino, V.; Humensky, T. B.; Jenke, P.; Kaaret, P.; Kieda, D.; Limon, M.; Mognet, I.; Mukherjee, R.; Nieto, D.; Okumura, A.; Peck, A.; Petrashyk, A.; Ribeiro, D.; Stevenson, B.; Vassiliev, V.; Yu, P.

    2015-09-01

    The construction of a prototype Schwarzschild-Couder telescope (pSCT) started in early June 2015 at the Fred Lawrence Whipple Observatory in Southern Arizona, as a candidate medium-sized telescope for the Cherenkov Telescope Array (CTA). Compared to current Davies-Cotton telescopes, this novel instrument with an aplanatic two-mirror optical system will offer a wider field-of-view and improved angular resolution. In addition, the reduced plate scale of the camera allows the use of highly-integrated photon detectors such as silicon photo multipliers. As part of CTA, this design has the potential to greatly improve the performance of the next generation ground-based observatory for very high-energy (E>60 GeV) gamma-ray astronomy. In this contribution we present the design and performance of both optical and alignment systems of the pSCT.

  6. Networked Virtual Organizations: A Chance for Small and Medium Sized Enterprises on Global Markets

    NASA Astrophysics Data System (ADS)

    Cellary, Wojciech

    Networked Virtual Organizations (NVOs) are a right answer to challenges of globalized, diversified, and dynamic contemporary economy. NVOs need more than e-trade and outsourcing, namely, they need out-tasking and e-collaboration. To out-task, but retain control on the way a task is performed by an external partner, two integrations are required: (1) integration of computer management systems of enterprises cooperating within an NVO; and (2) integration of cooperating representatives of NVO member enterprises into a virtual team. NVOs provide a particular chance to Small and Medium size Enterprises (SMEs) to find their place on global markets and to play a significant role on them. Requirements for SMEs to be able to successfully join an NVO are analyzed in the paper.

  7. Larval assemblages of large and medium-sized pelagic species in the Straits of Florida

    NASA Astrophysics Data System (ADS)

    Richardson, David E.; Llopiz, Joel K.; Guigand, Cedric M.; Cowen, Robert K.

    2010-07-01

    Critical gaps in our understanding of the distributions, interactions, life histories and preferred habitats of large and medium-size pelagic fishes severely constrain the implementation of ecosystem-based, spatially structured fisheries management approaches. In particular, spawning distributions and the environmental characteristics associated with the early life stages are poorly documented. In this study, we consider the diversity, assemblages, and associated habitat of the larvae of large and medium-sized pelagic species collected during 2 years of monthly surveys across the Straits of Florida. In total, 36 taxa and 14,295 individuals were collected, with the highest diversity occurring during the summer and in the western, frontal region of the Florida Current. Only a few species (e.g. Thunnus obesus, T. alalunga, Tetrapturus pfluegeri) considered for this study were absent. Small scombrids (e.g. T. atlanticus, Katsuwonus pelamis, Auxis spp.) and gempylids dominated the catch and were orders of magnitude more abundant than many of the rare species (e.g. Thunnus thynnus,Kajikia albida). Both constrained (CCA) and unconstrained (NMDS) multivariate analyses revealed a number of species groupings including: (1) a summer Florida edge assemblage (e.g. Auxis spp., Euthynnus alleterattus, Istiophorus platypterus); (2) a summer offshore assemblage (e.g. Makaira nigricans, T. atlanticus, Ruvettus pretiosus, Lampris guttatus); (3) an ubiquitous assemblage (e.g. K. pelamis, Coryphaena hippurus, Xiphias gladius); and (4) a spring/winter assemblage that was widely dispersed in space (e.g. trachipterids). The primary environmental factors associated with these assemblages were sea-surface temperature (highest in summer-early fall), day length (highest in early summer), thermocline depth (shallowest on the Florida side) and fluorescence (highest on the Florida side). Overall, the results of this study provide insights into how a remarkable diversity of pelagic species

  8. Survey of food safety practices on small to medium-sized farms and in farmers markets.

    PubMed

    Harrison, Judy A; Gaskin, Julia W; Harrison, Mark A; Cannon, Jennifer L; Boyer, Renee R; Zehnder, Geoffrey W

    2013-11-01

    As produce consumption has increased, so have foodborne disease outbreaks associated with fresh produce. Little research has addressed food safety practices used on small to medium-sized farms selling locally or in farmers markets. This study evaluated current food safety practices used by farmers on small to medium-sized farms and managers of farmers markets in Georgia, Virginia, and South Carolina based on responses to surveys. Surveys were developed, pretested, and revised before implementation with target audiences and were implemented via mail and the Web to maximize participation, with reminders sent to nonrespondents. Data were collected from 226 farmers and 45 market managers. Frequencies and percentages were calculated for all response variables. Responses from farmers indicated that more than 56% of them use manures. Of those who use manures, 34% use raw or mixtures of raw and composted manure, and over 26% wait fewer than 90 days between application of raw manure and harvest. Over 27% use water sources that have not been tested for safety for irrigation, and 16% use such water sources for washing produce. Over 43% do not sanitize surfaces that touch produce at the farm. Only 33% of farmers always clean transport containers between uses. Responses from market managers indicated that over 42% have no food safety standards in place for the market. Only 2 to 11% ask farmers specific questions about conditions on the farm that could affect product safety. Less than 25% of managers sanitize market surfaces. Only 11% always clean market containers between uses. Over 75% of markets offer no sanitation training to workers or vendors. While farmers and market managers are using many good practices, the results indicate that some practices being used may put consumers at risk of foodborne illness. Consequently, there is a need for training for both farmers and market managers.

  9. Striatopallidal Neuron NMDA Receptors Control Synaptic Connectivity, Locomotor, and Goal-Directed Behaviors

    PubMed Central

    Lambot, Laurie; Chaves Rodriguez, Elena; Houtteman, Delphine; Li, Yuquing; Schiffmann, Serge N.; Gall, David

    2016-01-01

    The basal ganglia (BG) control action selection, motor programs, habits, and goal-directed learning. The striatum, the principal input structure of BG, is predominantly composed of medium-sized spiny neurons (MSNs). Arising from these spatially intermixed MSNs, two inhibitory outputs form two main efferent pathways, the direct and indirect pathways. Striatonigral MSNs give rise to the activating, direct pathway MSNs and striatopallidal MSNs to the inhibitory, indirect pathway (iMSNs). BG output nuclei integrate information from both pathways to fine-tune motor procedures and to acquire complex habits and skills. Therefore, balanced activity between both pathways is crucial for harmonious functions of the BG. Despite the increase in knowledge concerning the role of glutamate NMDA receptors (NMDA-Rs) in the striatum, understanding of the specific functions of NMDA-R iMSNs is still lacking. For this purpose, we generated a conditional knock-out mouse to address the functions of the NMDA-R in the indirect pathway. At the cellular level, deletion of GluN1 in iMSNs leads to a reduction in the number and strength of the excitatory corticostriatopallidal synapses. The subsequent scaling down in input integration leads to dysfunctional changes in BG output, which is seen as reduced habituation, delay in goal-directed learning, lack of associative behavior, and impairment in action selection or skill learning. The NMDA-R deletion in iMSNs causes a decrease in the synaptic strength of striatopallidal neurons, which in turn might lead to a imbalanced integration between direct and indirect MSN pathways, making mice less sensitive to environmental change. Therefore, their ability to learn and adapt to the environment-based experience was significantly affected. SIGNIFICANCE STATEMENT The striatum controls habits, locomotion, and goal-directed behaviors by coordinated activation of two antagonistic pathways. Insofar as NMDA receptors (NMDA-Rs) play a key role in synaptic

  10. 50 CFR 648.233 - Spiny dogfish Accountability Measures (AMs).

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 50 Wildlife and Fisheries 10 2011-10-01 2011-10-01 false Spiny dogfish Accountability Measures... Management Measures for the Spiny Dogfish Fishery § 648.233 Spiny dogfish Accountability Measures (AMs). (a... dogfish on that date for the remainder of that semi-annual period by publishing notification in...

  11. 50 CFR 648.233 - Spiny dogfish Accountability Measures (AMs).

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 50 Wildlife and Fisheries 12 2012-10-01 2012-10-01 false Spiny dogfish Accountability Measures... Management Measures for the Spiny Dogfish Fishery § 648.233 Spiny dogfish Accountability Measures (AMs). (a... dogfish on that date for the remainder of that semi-annual period by publishing notification in...

  12. 50 CFR 648.233 - Spiny dogfish Accountability Measures (AMs).

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 50 Wildlife and Fisheries 12 2013-10-01 2013-10-01 false Spiny dogfish Accountability Measures... Management Measures for the Spiny Dogfish Fishery § 648.233 Spiny dogfish Accountability Measures (AMs). (a... dogfish on that date for the remainder of that semi-annual period by publishing notification in...

  13. 50 CFR 640.27 - Spiny lobster import prohibitions.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 50 Wildlife and Fisheries 8 2010-10-01 2010-10-01 false Spiny lobster import prohibitions. 640.27... ATMOSPHERIC ADMINISTRATION, DEPARTMENT OF COMMERCE SPINY LOBSTER FISHERY OF THE GULF OF MEXICO AND SOUTH ATLANTIC Management Measures § 640.27 Spiny lobster import prohibitions. (a) Minimum size limits...

  14. 50 CFR 622.50 - Caribbean spiny lobster import prohibitions.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 50 Wildlife and Fisheries 10 2011-10-01 2011-10-01 false Caribbean spiny lobster import... ATLANTIC Management Measures § 622.50 Caribbean spiny lobster import prohibitions. (a) Minimum size limits for imported spiny lobster. There are two minimum size limits that apply to importation of...

  15. 50 CFR 622.50 - Caribbean spiny lobster import prohibitions.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 50 Wildlife and Fisheries 8 2010-10-01 2010-10-01 false Caribbean spiny lobster import... ATLANTIC Management Measures § 622.50 Caribbean spiny lobster import prohibitions. (a) Minimum size limits for imported spiny lobster. There are two minimum size limits that apply to importation of...

  16. 50 CFR 640.27 - Spiny lobster import prohibitions.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 50 Wildlife and Fisheries 12 2012-10-01 2012-10-01 false Spiny lobster import prohibitions. 640.27... ATMOSPHERIC ADMINISTRATION, DEPARTMENT OF COMMERCE SPINY LOBSTER FISHERY OF THE GULF OF MEXICO AND SOUTH ATLANTIC Management Measures § 640.27 Spiny lobster import prohibitions. (a) Minimum size limits...

  17. 50 CFR 622.50 - Caribbean spiny lobster import prohibitions.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 50 Wildlife and Fisheries 12 2012-10-01 2012-10-01 false Caribbean spiny lobster import... ATLANTIC Management Measures § 622.50 Caribbean spiny lobster import prohibitions. (a) Minimum size limits for imported spiny lobster. There are two minimum size limits that apply to importation of...

  18. 50 CFR 640.27 - Spiny lobster import prohibitions.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 50 Wildlife and Fisheries 10 2011-10-01 2011-10-01 false Spiny lobster import prohibitions. 640.27... ATMOSPHERIC ADMINISTRATION, DEPARTMENT OF COMMERCE SPINY LOBSTER FISHERY OF THE GULF OF MEXICO AND SOUTH ATLANTIC Management Measures § 640.27 Spiny lobster import prohibitions. (a) Minimum size limits...

  19. Morphology, topography and cytoarchitectonics of the pterygopalatine ganglion in Egyptian spiny mouse (Acomys cahirinus, Desmarest).

    PubMed

    Szczurkowski, Aleksander; Kuder, Tadeusz; Nowak, Elzbieta; Kuchinka, Jacek

    2002-01-01

    Using the thiocholine method of Koelle and Friedenwald and histological techniques the pterygopalatine ganglion in Egyptian spiny mouse (Acomys cahirinus, Desmarest) was studied. The ganglion was found to be a single irregular cluster of neurocytes, situated on the medial surface of the maxillary nerve. The ganglion is composed of oval, elliptical and sometimes fusiform ganglionic neurones in compact arrangement without a thick connective-tissue capsule.

  20. Morphology, topography and cytoarchitectonics of the otic ganglion in Egyptian spiny mouse (Acomys cahirinus, Desmarest).

    PubMed

    Szczurkowski, A; Kuder, T; Nowak, E; Kuchinka, J

    2001-01-01

    Using the thiocholine method of Koelle and Friedenwald and histological techniques, the otic ganglion in Egyptian spiny mouse (Acomys cahirinus, Desmarest) was studied. The ganglion was found to be a single oval cluster of neurocytes, situated at the medial and posterior surface of the mandibular nerve just above the maxillary artery. The ganglion is composed of typical ganglionic neurons in compact arrangement without a thick connective-tissue capsule.

  1. Gastrointestinal nematodes in grazing dairy cattle from small and medium-sized farms in southern Poland.

    PubMed

    Piekarska, J; Płoneczka-Janeczko, K; Kantyka, M; Kuczaj, M; Gorczykowski, M; Janeczko, K

    2013-11-15

    This study aimed to estimate the prevalence of gastrointestinal nematodes and the intensity of infection in grazing dairy cattle from small and medium-sized farms in southern Poland. The level of antibodies against Ostertagia ostertagi in the bulk tank milk (BTM) from the animals was also assessed. Rectal fecal samples collected from 361 cows on 20 farms were examined using Willis-Schlaaf flotation and the McMaster method. BTM samples were tested for the presence of O. ostertagi antibodies using ELISA. Multiplex PCR was used to identify the third-stage larvae (L3) of gastrointestinal nematodes derived from the culture of pooled fecal samples from sampled farms. Gastrointestinal nematode eggs were found in the samples from 18 of the 20 herds with a prevalence range from 20.4 to 94.5%. The average number of eggs excreted in the feces of the herds was 200 eggs per gram (EPG). Antibodies to O. ostertagi were found in 20 of the examined herds (100%), of which 6 had optical density ratios (ODR) greater than 0.5. PCR results showed the presence of three nematode species: Ostertagia ostertagi, Cooperia oncophora and Oesophagostomum radiatum.

  2. Hybrid neural intelligent system to predict business failure in small-to-medium-size enterprises.

    PubMed

    Borrajo, M Lourdes; Baruque, Bruno; Corchado, Emilio; Bajo, Javier; Corchado, Juan M

    2011-08-01

    During the last years there has been a growing need of developing innovative tools that can help small to medium sized enterprises to predict business failure as well as financial crisis. In this study we present a novel hybrid intelligent system aimed at monitoring the modus operandi of the companies and predicting possible failures. This system is implemented by means of a neural-based multi-agent system that models the different actors of the companies as agents. The core of the multi-agent system is a type of agent that incorporates a case-based reasoning system and automates the business control process and failure prediction. The stages of the case-based reasoning system are implemented by means of web services: the retrieval stage uses an innovative weighted voting summarization of self-organizing maps ensembles-based method and the reuse stage is implemented by means of a radial basis function neural network. An initial prototype was developed and the results obtained related to small and medium enterprises in a real scenario are presented.

  3. An effective physical fitness program for small and medium-sized enterprises.

    PubMed

    Tsai, Han Hui; Peng, Shu Mei; Yeh, Ching Ying; Chen, Chiou Jong; Chen, Ruey Yu

    2011-01-01

    The aim of this study is to develop a practicable worksite physical fitness program for small and medium-sized enterprises (SMEs). Community-based intervention consisting of a three-month exercise course was conducted, and its benefits evaluated. A self-administrated structured questionnaire and physical fitness examination were designed to compare the difference between pre and post intervention. A total of 133 SME workers completed the lifestyle/exercise course and filled out the questionnaire, but 16 were excluded from the exercise group due to health reasons. After the intervention, health indicators such as weight, blood pressure, resting heart rate, waistline, BMI, front and back trunk flexibility, abdominal muscle durability and back muscle strength were significantly improved, and improvements in musculoskeletal disorders were seen in reduced neck pain (18.8%), wrist pain (17.4%), and upper/lower back pain (8.7% and 21.7%, respectively). Cardiovascular risk factors (BMI and resting heart rate) showed a significant improvement related to frequent participation in the program (p=0.02), and the exercise group reported a significant difference in overall health (p=0.02). This study has demonstrated an effective approach to community-based fitness intervention through SMEs.

  4. Quantitative evaluation of waste prevention on the level of small and medium sized enterprises (SMEs).

    PubMed

    Laner, David; Rechberger, Helmut

    2009-02-01

    Waste prevention is a principle means of achieving the goals of waste management and a key element for developing sustainable economies. Small and medium sized enterprises (SMEs) contribute substantially to environmental degradation, often not even being aware of their environmental effects. Therefore, several initiatives have been launched in Austria aimed at supporting waste prevention measures on the level of SMEs. To promote the most efficient projects, they have to be evaluated with respect to their contribution to the goals of waste management. It is the aim of this paper to develop a methodology for evaluating waste prevention measures in SMEs based on their goal orientation. At first, conceptual problems of defining and delineating waste prevention activities are briefly discussed. Then an approach to evaluate waste prevention activities with respect to their environmental performance is presented and benchmarks which allow for an efficient use of the available funds are developed. Finally the evaluation method is applied to a number of former projects and the calculated results are analysed with respect to shortcomings and limitations of the model. It is found that the developed methodology can provide a tool for a more objective and comprehensible evaluation of waste prevention measures.

  5. Resource efficiency and culture--workplace training for small and medium-sized enterprises.

    PubMed

    Bliesner, Anna; Liedtke, Christa; Rohn, Holger

    2014-05-15

    Although there are already some qualification offers available for enterprises to support resource efficiency innovations, the high potentials that can be identified especially for small and medium sized enterprises (SMEs) have not been activated until now. As successful change lies in the hands of humans, the main aim of vocational education has to be the promotion of organisational and cultural changes in the enterprises. As there is already a small but increasing number of enterprises that perform very well in resource efficiency innovations one question arises: What are typical characteristics of those enterprises? Leaning on a good-practice approach, the project "ResourceCulture" is going to prove or falsify the hypothesis that enterprises being successful with resource efficiency innovations have a specific culture of trust, which substantially contributes to innovation processes, or even initially enables them. Detailed empirical field research will light up which correlations between resource efficiency, innovation and cultures of trust can be found and will offer important aspects for the improvement of management instruments and qualification concepts for workplace training. The project seizes qualification needs that were likewise mentioned by enterprises and consultants, regarding the implementation of resource efficiency. This article - based on first empirical field research results - derives preliminary indications for the design of the qualification module for the target groups resource efficiency consultants and managers. On this basis and in order to implement "ResourceCulture" conceptual and methodological starting points for workplace training are outlined.

  6. Sustainability indices as a tool for urban managers, evidence from four medium-sized Chinese cities

    SciTech Connect

    Dijk, Meine Pieter van . E-mail: mpvandijk@few.eur.nl; Zhang Mingshun . E-mail: z.mingshun@ihs.nl

    2005-08-15

    This research in four medium-sized Chinese cities aims at measuring urban sustainability in China and focuses on three issues. First, the situation in these four cities with regard to urban sustainability is evaluated. Secondly, a number of relations between different aspects of urban sustainability is explored. Finally, it is indicated how urban managers can improve with sustainability indices as tools currently ineffective urban management practices. Although all four cities are moving towards sustainable development, the current situation shows still weak sustainability in three, and even non-sustainability in one city. The social and, in particular, the economic dimensions of urban sustainability make significant positive contributions to overall urban sustainability. However, the decline of natural resources and environmental degradation are influencing it negatively. It is therefore suggested that more priority should be assigned to urban environmental protection and management in China. The fundamental reason for environmental degradation is believed to be inefficient urban management. To implement effective urban management in China, there is an urgent need to redefine the role of local government, reform local organizational structure, enhance local participatory institutional capacity, properly distribute the urban welfare, and thus integrate economic, social and environmental objectives local strategic and action plans.

  7. Diode laser anastemoses of medium-size arteries with indocyanine green dye-enhanced albumine

    NASA Astrophysics Data System (ADS)

    Weng, Guo-Xing; Williamson, Warren; Aretz, H. Thomas

    1998-11-01

    In order to achieve a better long-term patency result and solve the problem of tensile strength in laser artery anastomoses, diode laser and Indocyanine Green (ICG) enhanced albumin were applied to medium-size artery anastomoses with three different methods, that is, direct laser vascular anastomoses, direct method enforced with ICG albumin, and laser welding with ICG albumin as 'solder'. Internal mammary artery (IMA) harvested from patients undergoing coronary bypass procedures, in vivo rat abdominal artery, and in vitro swine heart and IMA were chosen as the experimental materials. The results revealed that only 3.15 +/- 0.36 minutes were required for each anastomosis; the bursting pressure and tensile strength were greater in the groups enforced with ICG albumin and laser welding than that with direct laser anastomoses. In the laser soldering group, the thermal damage was limited in the adventitial layer, only at a depth of 200 micrometers . There was also a satisfied result in the in vivo laser welding rat's abdominal adventitial layer, only at a depth of 200 micrometers . There was also a satisfied result in the in vivo laser welding rat's abdominal arteries. However, end-to-side laser welding of IMA soronary artery with ICG albumin needs further investigation about its tensile strength in an in vivo model.

  8. A radiophotoluminescent glass plate system for medium-sized field dosimetry

    SciTech Connect

    Nakagawa, Keiichi; Koyanagi, Hiroki; Shiraki, Takashi; Saegusa, Shigeki; Sasaki, Katsutake; Oritate, Takashi; Mima, Kazuo; Miyazawa, Masanori; Ishidoya, Tatsuyo; Ohtomo, Kuni; Yoda, Kiyoshi

    2005-10-15

    A two-dimensional radiophotoluminescent system for medium-sized field dosimetry has been developed using a silver-activated phosphate glass plate with a dimension of 120 mmx120 mmx1 mm and a readout unit comprising a UV excitation lamp and a CCD imager. A dose ranging from 0 to 400 cGy, provided by a 6 MV x-ray beam, was delivered to the glass plate oriented perpendicularly to the beam and positioned in a water phantom at a depth of 10 cm, where the center of the glass plate coincided with the linac isocenter. After the dose delivery, the glass plate was placed in the readout system. The CCD output intensity increased linearly with the applied dose. The angular dependence of response on the direction of radiation incidence was measured by rotating the glass plate in the water phantom, indicating that the output remained constant up to 75 deg. from perpendicular incident direction, followed by a steep reduction down to 85% at an angle of 90 deg. A lateral dose distribution resulting from a 60 mmx60 mm irradiation was compared between the glass plate and an x-ray film having had the same exposure, showing that the glass plate and the x-ray film led to identical dose distributions. The dose reproducibility for a glass plate and the sensitivity variation among different glass plates were also evaluated.

  9. Understanding the structural transformation, stability of medium-sized neutral and charged silicon clusters

    PubMed Central

    Ding, Li Ping; Zhang, Fang Hui; Zhu, Yong Sheng; Lu, Cheng; Kuang, Xiao Yu; Lv, Jian; Shao, Peng

    2015-01-01

    The structural and electronic properties for the global minimum structures of medium-sized neutral, anionic and cationic Sinμ (n = 20–30, μ = 0, −1 and +1) clusters have been studied using an unbiased CALYPSO structure searching method in conjunction with first-principles calculations. A large number of low-lying isomers are optimized at the B3PW91/6-311 + G* level of theory. Harmonic vibrational analysis has been performed to assure that the optimized geometries are stable. The growth behaviors clearly indicate that a structural transition from the prolate to spherical-like geometries occurs at n = 26 for neutral silicon clusters, n = 27 for anions and n = 25 for cations. These results are in good agreement with the available experimental and theoretical predicted findings. In addition, no significant structural differences are observed between the neutral and cation charged silicon clusters with n = 20–24, both of them favor prolate structures. The HOMO-LUMO gaps and vertical ionization potential patterns indicate that Si22 is the most chemical stable cluster, and its dynamical stability is deeply discussed by the vibrational spectra calculations. PMID:26526519

  10. Understanding the structural transformation, stability of medium-sized neutral and charged silicon clusters.

    PubMed

    Ding, Li Ping; Zhang, Fang Hui; Zhu, Yong Sheng; Lu, Cheng; Kuang, Xiao Yu; Lv, Jian; Shao, Peng

    2015-11-03

    The structural and electronic properties for the global minimum structures of medium-sized neutral, anionic and cationic Sin(μ) (n = 20-30, μ = 0, -1 and +1) clusters have been studied using an unbiased CALYPSO structure searching method in conjunction with first-principles calculations. A large number of low-lying isomers are optimized at the B3PW91/6-311 + G* level of theory. Harmonic vibrational analysis has been performed to assure that the optimized geometries are stable. The growth behaviors clearly indicate that a structural transition from the prolate to spherical-like geometries occurs at n = 26 for neutral silicon clusters, n = 27 for anions and n = 25 for cations. These results are in good agreement with the available experimental and theoretical predicted findings. In addition, no significant structural differences are observed between the neutral and cation charged silicon clusters with n = 20-24, both of them favor prolate structures. The HOMO-LUMO gaps and vertical ionization potential patterns indicate that Si22 is the most chemical stable cluster, and its dynamical stability is deeply discussed by the vibrational spectra calculations.

  11. Modeling, simulation, and concept design for hybrid-electric medium-size military trucks

    NASA Astrophysics Data System (ADS)

    Rizzoni, Giorgio; Josephson, John R.; Soliman, Ahmed; Hubert, Christopher; Cantemir, Codrin-Gruie; Dembski, Nicholas; Pisu, Pierluigi; Mikesell, David; Serrao, Lorenzo; Russell, James; Carroll, Mark

    2005-05-01

    A large scale design space exploration can provide valuable insight into vehicle design tradeoffs being considered for the U.S. Army"s FMTV (Family of Medium Tactical Vehicles). Through a grant from TACOM (Tank-automotive and Armaments Command), researchers have generated detailed road, surface, and grade conditions representative of the performance criteria of this medium-sized truck and constructed a virtual powertrain simulator for both conventional and hybrid variants. The simulator incorporates the latest technology among vehicle design options, including scalable ultracapacitor and NiMH battery packs as well as a variety of generator and traction motor configurations. An energy management control strategy has also been developed to provide efficiency and performance. A design space exploration for the family of vehicles involves running a large number of simulations with systematically varied vehicle design parameters, where each variant is paced through several different mission profiles and multiple attributes of performance are measured. The resulting designs are filtered to remove dominated designs, exposing the multi-criterial surface of optimality (Pareto optimal designs), and revealing the design tradeoffs as they impact vehicle performance and economy. The results are not yet definitive because ride and drivability measures were not included, and work is not finished on fine-tuning the modeled dynamics of some powertrain components. However, the work so far completed demonstrates the effectiveness of the approach to design space exploration, and the results to date suggest the powertrain configuration best suited to the FMTV mission.

  12. Generation of antitumor active neutral medium-sized alpha-glycan in apple vinegar fermentation.

    PubMed

    Abe, Kaoru; Kushibiki, Toshisada; Matsue, Hajime; Furukawa, Ken-Ichi; Motomura, Shigeru

    2007-09-01

    The physiologically active substances in apple vinegar have not yet been chemically characterized. We studied the biological functions of apple vinegar produced from crushed apples, and found that the constituent neutral medium-sized alpha-glycan (NMalphaG) acts as an antitumor agent against experimental mouse tumors. NMalphaG is a homoglycan composed of glucose having a molecular weight of about 10,000 and a branched structure bearing alpha (1-4,6) linkages. In this study, we clarified the origin of NMalphaG in apple vinegar by examination of its content in alcohol and acetic acid fermentation products sequentially. We found that NMalphaG appeared in acetic acid fermentation, but not in alcohol fermentation. Furthermore we investigated NMalphaG origin using acetic acid fermentation from alcohol fortifiied apple without alcohol fermentation and from raw material with varying amounts of pomace. The results indicate that NMalphaG originated in the apple fruit body and that its production requires both fermentation processes.

  13. Evaluating the control software for CTA in a medium size telescope prototype

    NASA Astrophysics Data System (ADS)

    Oya, I.; Behera, B.; Birsin, E.; Koeppel, H.; Melkumyan, D.; Schmidt, T.; Schwanke, U.; Wegner, P.; Wiesand, S.; Winde, M.; Consortium, CTA

    2012-12-01

    CTA (Cherenkov Telescope Array) is one of the largest ground-based astronomy projects being pursued and will be the largest facility for ground-based γ-ray observations ever built. CTA will consist of two arrays (one in the Northern hemisphere and one in the Southern hemisphere) composed of telescopes of several sizes. A prototype for the Medium Size Telescope (MST) of a diameter of 12 m will be installed in Berlin by the end of 2012. This MST prototype will be composed of the mechanical structure, drive system and mirror facets mounted with powered actuators to enable active control. Five Charge-Coupled Device (CCD) cameras and a weather station will allow the measurement of the performance of the instrument. The Atacama Large Millimeter/submillimeter Array (ALMA) Common Software (ACS) distributed control framework is currently being considered by the CTA consortium to serve as the array control middleware. In order to evaluate the ACS software, it has been decided to implement an ACS-based readout and control system for the MST prototype. The design of the control software is following the concepts and tools under evaluation within the CTA consortium, like the use of a Unified Modeling Language (UML) based code generation framework for ACS component modeling, and the use of OPen Connectivity-Unified Architecture (OPC UA) for hardware access. In this contribution, the progress in the implementation of the control system for this CTA prototype telescope is described.

  14. Computational fluid dynamic modeling of a medium-sized surface mine blasthole drill shroud

    PubMed Central

    Zheng, Y.; Reed, W.R.; Zhou, L.; Rider, J.P.

    2016-01-01

    The Pittsburgh Mining Research Division of the U.S. National Institute for Occupational Safety and Health (NIOSH) recently developed a series of models using computational fluid dynamics (CFD) to study airflows and respirable dust distribution associated with a medium-sized surface blasthole drill shroud with a dry dust collector system. Previously run experiments conducted in NIOSH’s full-scale drill shroud laboratory were used to validate the models. The setup values in the CFD models were calculated from experimental data obtained from the drill shroud laboratory and measurements of test material particle size. Subsequent simulation results were compared with the experimental data for several test scenarios, including 0.14 m3/s (300 cfm) and 0.24 m3/s (500 cfm) bailing airflow with 2:1, 3:1 and 4:1 dust collector-to-bailing airflow ratios. For the 2:1 and 3:1 ratios, the calculated dust concentrations from the CFD models were within the 95 percent confidence intervals of the experimental data. This paper describes the methodology used to develop the CFD models, to calculate the model input and to validate the models based on the experimental data. Problem regions were identified and revealed by the study. The simulation results could be used for future development of dust control methods for a surface mine blasthole drill shroud. PMID:27932851

  15. Mousso structure: A deeply eroded, medium-sized, complex impact crater in northern Chad?

    NASA Astrophysics Data System (ADS)

    Buchner, Elmar; Schmieder, Martin

    2007-10-01

    The Mousso structure, a complex, ˜3.8 km circular structure centred on 17°58' N/19°53' E and located near the Mousso oasis, Borkou-Ennedi-Tibesti, northern Chad, displays structural features typical for complex impact structures: a circular rim with concentric faults, an annular basin, and a central peak. Remote sensing investigations based on Landsat-7 Enhanced Thematic Mapper Plus (ETM+) and Shuttle Radar Topographic Mission (SRTM) data reveal a specific morphological-structural resemblance of the complex central peak of the Mousso structure to the central uplift of the Spider impact structure, Western Australia, and, to some degree, to the central uplifts of the Upheaval Dome, Sierra Madera, and Gosses Bluff impact structures. This is consistent with the layered sedimentary rocks associated with all of these structures. No endogenic geological processes such as magmatism, diapirism, karst dissolution, and glacial or fluvial erosion can conclusively explain the formation of the Mousso structure within a large area of flat-lying early Paleozoic sandstones. Thus, this paper proposes that the Mousso structure might represent a deeply eroded, medium-sized, complex impact structure. As field investigations are currently impossible due to the civil war in Chad, the search for shock-metamorphic effects in rocks of the Mousso structure remains outstanding.

  16. Experimental testing of centrifugal pump: small and medium sized enterprise product

    NASA Astrophysics Data System (ADS)

    Ismail, R.; Paddiyatu, F.; Khafidh, M.; Nugroho, S.; Sugiyanto, S.; Jamari, J.

    2014-06-01

    This paper reports the experimental testing for centrifugal pump for fisherman ship, manufactured by small and medium sized enterprises in Central Java Province, Indonesia. The research covers material analysis, component observation, endurance and vibration test. Six centrifugal pumps are tested and three main pump components are discussed: shaft, bearings and seals. The results show that the material of the shaft is predicted to support and transmit the load from the engine to impeller. The problem found in the tolerance and geometry accuracy of the shaft which causes difficulties during assembling process, excessive wear and leakage during testing. From the endurance and vibration test, the ball bearings fail and lock the shaft due to the fatigue on the rolling elements and raceways. The oil seal and water seal also fail in maintaining the oil and water in the chamber and induce the unlubricated system for the ball bearings. Some suggestions are delivered to improve the product quality of the centrifugal pump. A good quality of the centrifugal pump for fishermen ship and long life span is expected to be produced by local SMEs to win the free trade competition in the Indonesian market.

  17. Fully Flexible Docking of Medium Sized Ligand Libraries with RosettaLigand

    PubMed Central

    DeLuca, Samuel; Khar, Karen; Meiler, Jens

    2015-01-01

    RosettaLigand has been successfully used to predict binding poses in protein-small molecule complexes. However, the RosettaLigand docking protocol is comparatively slow in identifying an initial starting pose for the small molecule (ligand) making it unfeasible for use in virtual High Throughput Screening (vHTS). To overcome this limitation, we developed a new sampling approach for placing the ligand in the protein binding site during the initial ‘low-resolution’ docking step. It combines the translational and rotational adjustments to the ligand pose in a single transformation step. The new algorithm is both more accurate and more time-efficient. The docking success rate is improved by 10–15% in a benchmark set of 43 protein/ligand complexes, reducing the number of models that typically need to be generated from 1000 to 150. The average time to generate a model is reduced from 50 seconds to 10 seconds. As a result we observe an effective 30-fold speed increase, making RosettaLigand appropriate for docking medium sized ligand libraries. We demonstrate that this improved initial placement of the ligand is critical for successful prediction of an accurate binding position in the ‘high-resolution’ full atom refinement step. PMID:26207742

  18. Feasibility of a medium-size central cogenerated energy facility, energy management memorandum

    NASA Astrophysics Data System (ADS)

    Porter, R. W.

    1982-09-01

    The thermal-economic feasibility was studied of a medium-size central cogenerated energy facility designed to serve five varied industries. Generation options included one dual-fuel diesel and one gas turbine, both with waste heat boilers, and five fired boilers. Fuels included natural gas, and for the fired-boiler cases, also low-sulphur coal and municipal refuse. The fired-boiler cogeneration systems employed back-pressure steam turbines. For coal and refuse, the option of steam only without cogeneration was also assessed. The refuse-fired cases utilized modular incinerators. The options provided for a wide range of steam and electrical capacities. Deficient steam was assumed generated independently in existing equipment. Excess electrical power over that which could be displaced was assumed sold to Commonwealth Edison Company under PURPA (Public Utility Regulator Policies Act). The facility was assumed operated by a mutually owned corporation formed by the cogenerated power users. The economic analysis was predicted on currently applicable energy-investment tax credits and accelerated depreciation for a January 1985 startup date. Based on 100% equity financing, the results indicated that the best alternative was the modular-incinerator cogeneration system.

  19. Drivers for OSH interventions in small and medium-sized enterprises.

    PubMed

    Cagno, Enrico; Masi, Donato; Leão, Celina Pinto

    2016-01-01

    The debate concerning occupational safety and health (OSH) interventions has recently focused on the need of improving the evaluation of interventions, and in particular on the need for providing information about why the intervention worked or not, under what circumstances and in which context. Key concepts in the analysis of the context are the drivers, i.e., those factors enabling, fostering or facilitating OSH interventions. However, the concept of driver for an OSH intervention is both confused and contested. Although the term is widely used, there is little consensus on how drivers should be understood, how important they are in different contexts and how they can facilitate interventions. This exploratory study based on interviews with the owner-managers and the safety officers of small and medium-sized enterprises (SMEs) gives an overview of the most characteristic drivers for OSH interventions. The results will be used to make an initial evaluation of SMEs' needs, and will help orient interventions and future research.

  20. TELICS—A Telescope Instrument Control System for Small/Medium Sized Astronomical Observatories

    NASA Astrophysics Data System (ADS)

    Srivastava, Mudit K.; Ramaprakash, A. N.; Burse, Mahesh P.; Chordia, Pravin A.; Chillal, Kalpesh S.; Mestry, Vilas B.; Das, Hillol K.; Kohok, Abhay A.

    2009-10-01

    For any modern astronomical observatory, it is essential to have an efficient interface between the telescope and its back-end instruments. However, for small and medium-sized observatories, this requirement is often limited by tight financial constraints. Therefore a simple yet versatile and low-cost control system is required for such observatories to minimize cost and effort. Here we report the development of a modern, multipurpose instrument control system TELICS (Telescope Instrument Control System) to integrate the controls of various instruments and devices mounted on the telescope. TELICS consists of an embedded hardware unit known as a common control unit (CCU) in combination with Linux-based data acquisition and user interface. The hardware of the CCU is built around the ATmega 128 microcontroller (Atmel Corp.) and is designed with a backplane, master-slave architecture. A Qt-based graphical user interface (GUI) has been developed and the back-end application software is based on C/C++. TELICS provides feedback mechanisms that give the operator good visibility and a quick-look display of the status and modes of instruments as well as data. TELICS has been used for regular science observations since 2008 March on the 2 m, f/10 IUCAA Telescope located at Girawali in Pune, India.

  1. Place and type of meals consumed by adults in medium sized cities

    PubMed Central

    Carús, Juliana Pires; França, Giovanny V A; Barros, Aluísio J D

    2014-01-01

    OBJECTIVE To describe the meals consumed by adults living in a midsize city in the South of Brazil, according to the place and preparation. METHODS A population-based cross-sectional study was conducted in Pelotas, Southern Brazil, in 2012. The two-stage sampling design used the 2010 census tracts as primary sampling units. Data were collected on the place of meals (at home or out) and on the kind of preparations consumed at home (homemade, snacks, take away food) covering the two days prior to the interview, using a standardized questionnaire. RESULTS The study included 2,927 adults, of which 59.0% were female, 60.0% were below 50 years of age and 58.0% were in work. Data were collected on 11,581 meals consumed on the two days preceding the interview, 25.0% were consumed outside of the home at lunchtime, and 10.0% at dinnertime. Considering home meals, most participants reported eating food prepared at home at both lunch and dinner. The majority of out-of-home meals (64.0% for lunch and 61.0% for dinner) were consumed in the work place, mostly based on food prepared at home. Individuals eating out of home were mostly male, young and highly educated. The occupational categories that ate at restaurants more often were trade workers, businessmen, teachers and graduate professionals. CONCLUSIONS Despite the changes in eating patterns described in Brazil in recent years, residents of medium-sized towns still mostly eat at home, consuming homemade food. PMID:24789639

  2. Clinical audit of multidisciplinary care at a medium-sized hospital in Spain

    PubMed Central

    2014-01-01

    Background Multidisciplinary care is a key enabler in the provision of high quality care for cancer patients. Despite compelling evidence supporting their benefit to patients and for providers, multidisciplinary cancer conferences (MCC) are not universally occurring. Team composition of MCC reflects the multidisciplinary nature of the body. Lack of nursing input can have a negative impact on team decision making. The objective of this study was to evaluate multidisciplinary care and adherence to national recommendations at a medium-sized hospital through a clinical audit of cancer conferences and clinical records. Methods A total of 77 multidisciplinary cancer conferences were visited and 496 electronic health records were reviewed. The regularity of meetings and multidisciplinary attendance were evaluated. Each electronic health record was checked to verify documented prospective discussion before any treatment was started. Results Nine multidisciplinary teams meet on a weekly or biweekly basis at the hospital with an average number of ten people and six different specialties represented. Average duration of meetings was 46.8 min. Though most patients (64.5%) were discussed at some point at the relevant cancer conference, only 40% had a documented multidisciplinary team discussion prior to the first treatment. Pathological stage (pTNM) was documented in 53.6% of clinical records. Conclusions Nursing representatives should be included as usual attendees at cancer conferences. Prospective discussion of all cancer cases should be encouraged. Use of checklists and systematic collection of key information, specifically cancer staging, could improve clinical documentation in the electronic clinical record. PMID:24597686

  3. Microbiological tap water profile of a medium-sized building and effect of water stagnation.

    PubMed

    Lipphaus, Patrick; Hammes, Frederik; Kötzsch, Stefan; Green, James; Gillespie, Simon; Nocker, Andreas

    2014-01-01

    Whereas microbiological quality of drinking water in water distribution systems is routinely monitored for reasons of legal compliance, microbial numbers in tap water are grossly understudied. Motivated by gross differences in water from private households, we applied in this study flow cytometry as a rapid analytical method to quantify microbial concentrations in water sampled at diverse taps in a medium size research building receiving chlorinated water. Taps differed considerably in frequency of usage and were located in laboratories, bathrooms, and a coffee kitchen. Substantial differences were observed between taps with concentrations (per mL) in the range from 6.29 x 10(3) to 7.74 x 10(5) for total cells and from 1.66 x 10(3) to 4.31 x 10(5) for intact cells. The percentage of intact cells varied between 7% and 96%. Water from taps with very infrequent use showed the highest bacterial numbers and the highest proportions of intact cells. Stagnation tended to increase microbial numbers in water from those taps which were otherwise frequently used. Microbial numbers in other taps that were rarely opened were not affected by stagnation as their water is probably mostly stagnant. For cold water taps, microbial numbers and the percentage of intact cells tended to decline with flushing with the greatest decline for taps used least frequently whereas microbial concentrations in water from hot water taps tended to be somewhat more stable. We conclude that microbiological water quality is mainly determined by building-specific parameters. Tap water profiling can provide valuable insight into plumbing system hygiene and maintenance.

  4. Morbidity of asylum seekers in a medium-sized German city.

    PubMed

    Führer, Amand; Eichner, Friederike; Stang, Andreas

    2016-07-01

    Asylum seekers constitute a particularly vulnerable group. Not only is their physical and mental health exposed to multiple stresses, but also their access to health care in Germany is legally restricted. Up to now, there is very limited scientific literature investigating the health-outcomes of asylum seekers in Germany. The aim of this study was to provide prevalence data on the morbidity and vaccination status of asylum seekers in a medium-sized German city. We used a structured questionnaire in a cross-sectional study on 214 adult asylum seekers (182 males, 24 females, 8 unknown) in Halle, Germany, 2015. The questionnaire inquired about the respondent's self-reported physical health and vaccination status and assessed their mental health using the Hopkins-Symptom-Checklist-25 and the Harvard Trauma Questionnaire. Pain (37.9 %) and psychological illness (depression: 54.7 %, anxiety disorder: 40.2 %; post-traumatic stress disorder: 18.2 %) were the most prevalent complaints. Among asylum seekers with psychological complaints, co-morbidity was high (64.2 % had more than one psychological disease). 5.6 % of the respondents mentioned suicidal thoughts. The prevalence of chronic diseases was low. We suggest interventions to improve asylum seekers' health on two levels: first, the obligatory initial medical examination after the refugees' arrival at the reception centre should be complemented with questions related to the vaccination status and the most common complaints including pain and psychological diseases. Second, medical infrastructure should be expanded to better serve the needs of culturally and linguistically diverse patient populations, so that those screened positive can be referred for early diagnosis and treatment.

  5. 40 CFR 141.81 - Applicability of corrosion control treatment steps to small, medium-size and large water systems.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... treatment steps to small, medium-size and large water systems. 141.81 Section 141.81 Protection of... WATER REGULATIONS Control of Lead and Copper § 141.81 Applicability of corrosion control treatment steps... review and approve the addition of a new source or long-term change in water treatment before it...

  6. 40 CFR 141.81 - Applicability of corrosion control treatment steps to small, medium-size and large water systems.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... treatment steps to small, medium-size and large water systems. 141.81 Section 141.81 Protection of... WATER REGULATIONS Control of Lead and Copper § 141.81 Applicability of corrosion control treatment steps... review and approve the addition of a new source or long-term change in water treatment before it...

  7. 40 CFR 141.81 - Applicability of corrosion control treatment steps to small, medium-size and large water systems.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... treatment steps to small, medium-size and large water systems. 141.81 Section 141.81 Protection of... WATER REGULATIONS Control of Lead and Copper § 141.81 Applicability of corrosion control treatment steps... review and approve the addition of a new source or long-term change in water treatment before it...

  8. Entrepreneurial Training for the Growth of Small and Medium-Sized Enterprises: Lessons from Central and Eastern Europe. Report.

    ERIC Educational Resources Information Center

    European Training Foundation, Turin (Italy).

    This report brings together a number of principles as to best practice in supporting, through training, growth of small and medium-sized enterprises (SMEs) in Central and Eastern Europe. Chapter 2 identifies key principles to be drawn from the West through a literature review. Chapter 3 reviews the "practice" of entrepreneurial training…

  9. The Anonymity of Catalan and the Authenticity of Estonian: Two Paths for the Development of Medium-Sized Languages

    ERIC Educational Resources Information Center

    Soler, Josep

    2013-01-01

    Catalan and Estonian can be considered "medium-sized" languages with some key common features that allow us to analyze the evolution of the two cases comparatively. Firstly, other formerly hegemonic languages (Spanish and Russian, respectively) have historically minoritized them. Secondly, the political equilibrium has now changed in…

  10. Revenue-Based Financial Modeling: A Sustainable Model for Medium-Size, Private, Mission-Based Schools of Education

    ERIC Educational Resources Information Center

    Harbouk, Joseph

    2011-01-01

    This study examined the implementation and assessment of revenue-based budgeting at a medium-size, private, mission-based graduate school of education (SOE), under the pseudonym Peter Claver University (PCU). Additionally, two other similar schools were included in the study because they used revenue-based budgeting for a period of 10 years or…

  11. Using Computer-Based Continuing Professional Education of Training Staff to Develop Small- and Medium-Sized Enterprises in Thailand

    ERIC Educational Resources Information Center

    Sooraksa, Nanta

    2012-01-01

    This paper describes a career development program for staff involved in providing training for small- and medium-sized enterprises (SMEs) in Thailand. Most of these staff were professional vocational teachers in schools. The program uses information communication technology (ICT), and its main objective is to teach Moodle software as a tool for…

  12. Using the Critical Incident Technique to Research Decision Making regarding Access to Training and Development in Medium-Sized Enterprises

    ERIC Educational Resources Information Center

    Coetzer, Alan; Redmond, Janice; Sharafizad, Jalleh

    2012-01-01

    Employees in small and medium-sized enterprises (SMEs) form part of a "disadvantaged" group within the workforce that receives less access to training and development (T&D) than employees in large firms. Prior research into reasons for the relatively low levels of employee participation in training and development has typically…

  13. 40 CFR 141.81 - Applicability of corrosion control treatment steps to small, medium-size and large water systems.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 23 2011-07-01 2011-07-01 false Applicability of corrosion control... WATER REGULATIONS Control of Lead and Copper § 141.81 Applicability of corrosion control treatment steps to small, medium-size and large water systems. (a) Systems shall complete the applicable...

  14. 40 CFR 141.81 - Applicability of corrosion control treatment steps to small, medium-size and large water systems.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 22 2010-07-01 2010-07-01 false Applicability of corrosion control... WATER REGULATIONS Control of Lead and Copper § 141.81 Applicability of corrosion control treatment steps to small, medium-size and large water systems. (a) Systems shall complete the applicable...

  15. Virtual Class: Distance Learning for Small and Medium Sized Enterprises in the Spanish Region of Castilla y Leon.

    ERIC Educational Resources Information Center

    Rodriguez, Blanca; Perez, Maria Angeles; Verdu, Maria Jesus; Navazo, Maria Agustina; Lopez, Ricardo; Mompo, Rafael; Garcia, Joaquin

    Lifelong learning is becoming a necessity in the new Information Society where everyone, particularly small and medium sized enterprises (SMEs), must keep up with new technologies. Education and training are of the most importance in this updating. An interdisciplinary and inter-university work group called "Canalejas" (Spain) has…

  16. A Bayesian Approach to International Distributor Selection for Small and Medium-Sized Enterprises in the Software Industry

    ERIC Educational Resources Information Center

    Lui, Joseph P.

    2013-01-01

    Identifying appropriate international distributors for small and medium-sized enterprises (SMEs) in the software industry for overseas markets can determine a firm's future endeavors in international expansion. SMEs lack the complex skills in market research and decision analysis to identify suitable partners to engage in global market entry.…

  17. Graduate Transition into Work: The Bridging Role of Graduate Placement Programmes in the Small- and Medium-Sized Enterprise Workplace

    ERIC Educational Resources Information Center

    Gallagher, Pádraig

    2015-01-01

    This research looks at the role of graduate placement programmes in bridging the gap between higher education and the small- and medium-sized enterprise (SME) sector. The research design and methodology used in this study was exploratory, in-depth and qualitative in nature. The research took the form of a multiple case study and focused on seven…

  18. Workplace Education Programs in Small and Medium-Sized Michigan Firms. Staff Working Paper 92-13.

    ERIC Educational Resources Information Center

    Hollenbeck, Kevin; Anderson, William

    A project collected data from small and medium-sized firms (employing fewer than 500) in Michigan concerning workplace education programs. It addressed why firms were or were not offering programs, program characteristics, and program impacts on firms and employees. Case studies of 28 businesses were undertaken from May 1991-July 1992 and a…

  19. Organoselenium and DMAP co-catalysis: regioselective synthesis of medium-sized halolactones and bromooxepanes from unactivated alkenes.

    PubMed

    Verma, Ajay; Jana, Sadhan; Prasad, Ch Durga; Yadav, Abhimanyu; Kumar, Sangit

    2016-03-18

    A catalytic system consisting of bis(4-methoxyphenyl)selenide and 4-(dimethylamino)pyridine (DMAP) has been developed for the regioselective synthesis of medium-sized bromo/iodo lactones and bromooxepanes possessing high transannular strain. (77)Se NMR, mass spectrometry and theoretical studies reveal that the reaction proceeds via a quaternary selenium intermediate.

  20. Attitudes about OCLC in Small and Medium-Sized Libraries. Illinois Valley Library System OCLC Experimental Project. Report No. 4.

    ERIC Educational Resources Information Center

    Bills, Linda G.; Wilford, Valerie

    A project was conducted from 1980 to 1982 to determine the costs and benefits of OCLC use in 29 small and medium-sized member libraries of the Illinois Valley Library System (IVLS). Academic, school, public, and special libraries participated in the project. Based on written attitude surveys of and interviews with library directors, staff,…

  1. 76 FR 52286 - Fisheries of the Northeastern United States; Spiny Dogfish Fishery; Commercial Period 1 Quota...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-08-22

    ... Northeastern United States; Spiny Dogfish Fishery; Commercial Period 1 Quota Harvested AGENCY: National Marine...: Temporary rule; closure of spiny dogfish fishery. SUMMARY: NMFS announces that the spiny dogfish commercial..., federally permitted spiny dogfish vessels may not fish for, possess, transfer, or land spiny dogfish...

  2. 77 FR 2022 - Fisheries of the Northeastern United States; Spiny Dogfish Fishery; Commercial Period 2 Quota...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-01-13

    ... Northeastern United States; Spiny Dogfish Fishery; Commercial Period 2 Quota Harvested AGENCY: National Marine...: Temporary rule; closure of spiny dogfish fishery. SUMMARY: NMFS announces that the spiny dogfish commercial..., federally permitted spiny dogfish vessels may not fish for, possess, transfer, or land spiny dogfish...

  3. 76 FR 17788 - Fisheries of the Northeastern United States; Spiny Dogfish Fishery; Annual Quota Harvested

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-03-31

    ... Northeastern United States; Spiny Dogfish Fishery; Annual Quota Harvested AGENCY: National Marine Fisheries...; closure of spiny dogfish fishery. SUMMARY: NMFS announces that the spiny dogfish commercial quota... spiny dogfish vessels may not fish for, possess, transfer, or land spiny dogfish until May 1, 2011,...

  4. 75 FR 4004 - Fisheries of the Northeastern United States; Spiny Dogfish Fishery; Commercial Period 2 Quota...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-01-26

    ... United States; Spiny Dogfish Fishery; Commercial Period 2 Quota Harvested AGENCY: National Marine...: Temporary rule; Closure of spiny dogfish fishery. SUMMARY: NMFS announces that the spiny dogfish commercial..., federally permitted spiny dogfish vessels may not fish for, possess, transfer, or land spiny dogfish...

  5. 75 FR 52650 - Fisheries of the Northeastern United States; Spiny Dogfish Fishery; Commercial Period 1 Quota...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-08-27

    ... United States; Spiny Dogfish Fishery; Commercial Period 1 Quota Harvested AGENCY: National Marine...: Temporary rule; closure of spiny dogfish fishery. SUMMARY: NMFS announces that the spiny dogfish commercial..., federally permitted spiny dogfish vessels may not fish for, possess, transfer, or land spiny dogfish...

  6. Think locally, act locally: Detection of small, medium-sized, and large communities in large networks

    NASA Astrophysics Data System (ADS)

    Jeub, Lucas G. S.; Balachandran, Prakash; Porter, Mason A.; Mucha, Peter J.; Mahoney, Michael W.

    2015-01-01

    It is common in the study of networks to investigate intermediate-sized (or "meso-scale") features to try to gain an understanding of network structure and function. For example, numerous algorithms have been developed to try to identify "communities," which are typically construed as sets of nodes with denser connections internally than with the remainder of a network. In this paper, we adopt a complementary perspective that communities are associated with bottlenecks of locally biased dynamical processes that begin at seed sets of nodes, and we employ several different community-identification procedures (using diffusion-based and geodesic-based dynamics) to investigate community quality as a function of community size. Using several empirical and synthetic networks, we identify several distinct scenarios for "size-resolved community structure" that can arise in real (and realistic) networks: (1) the best small groups of nodes can be better than the best large groups (for a given formulation of the idea of a good community); (2) the best small groups can have a quality that is comparable to the best medium-sized and large groups; and (3) the best small groups of nodes can be worse than the best large groups. As we discuss in detail, which of these three cases holds for a given network can make an enormous difference when investigating and making claims about network community structure, and it is important to take this into account to obtain reliable downstream conclusions. Depending on which scenario holds, one may or may not be able to successfully identify "good" communities in a given network (and good communities might not even exist for a given community quality measure), the manner in which different small communities fit together to form meso-scale network structures can be very different, and processes such as viral propagation and information diffusion can exhibit very different dynamics. In addition, our results suggest that, for many large realistic

  7. Development and Evaluation of Algorithms to Improve Small- and Medium-Size Commercial Building Operations

    SciTech Connect

    Kim, Woohyun; Katipamula, Srinivas; Lutes, Robert G.; Underhill, Ronald M.

    2016-10-31

    Small- and medium-sized (<100,000 sf) commercial buildings (SMBs) represent over 95% of the U.S. commercial building stock and consume over 60% of total site energy consumption. Many of these buildings use rudimentary controls that are mostly manual, with limited scheduling capability, no monitoring or failure management. Therefore, many of these buildings are operated inefficiently and consume excess energy. SMBs typically utilize packaged rooftop units (RTUs) that are controlled by an individual thermostat. There is increased urgency to improve the operating efficiency of existing commercial building stock in the U.S. for many reasons, chief among them is to mitigate the climate change impacts. Studies have shown that managing set points and schedules of the RTUs will result in up to 20% energy and cost savings. Another problem associated with RTUs is short-cycling, where an RTU goes through ON and OFF cycles too frequently. Excessive cycling can lead to excessive wear and lead to premature failure of the compressor or its components. The short cycling can result in a significantly decreased average efficiency (up to 10%), even if there are no physical failures in the equipment. Also, SMBs use a time-of-day scheduling is to start the RTUs before the building will be occupied and shut it off when unoccupied. Ensuring correct use of the zone set points and eliminating frequent cycling of RTUs thereby leading to persistent building operations can significantly increase the operational efficiency of the SMBs. A growing trend is to use low-cost control infrastructure that can enable scalable and cost-effective intelligent building operations. The work reported in this report describes three algorithms for detecting the zone set point temperature, RTU cycling rate and occupancy schedule detection that can be deployed on the low-cost infrastructure. These algorithms only require the zone temperature data for detection. The algorithms have been tested and validated using

  8. Karyotypes of some medium-sized Dytiscidae (Agabinae and Colymbetinae) (Coleoptera).

    PubMed

    Angus, Robert B; Clery, Molly J; Carter, Jodie C; Wenczek, Daniel E

    2013-01-01

    An account is given of the karyotypes of 29 species of medium sized Dytiscidae (Coleoptera). Of the 20 species of Agabus Leach, 1817, 18 have karyotypes comprising 21 pairs of autosomes and sex chromosomes which are either X0(♂) or XX (♀). These species are Agabus serricornis (Paykull, 1799), Agabus labiatus (Brahm, 1791), Agabus congener (Thunberg, 1794), Agabus lapponicus (Thomson, 1867), Agabus thomsoni (J. Sahlberg, 1871), Agabus confinis (Gyllenhal, 1808), Agabus sturmii (Gyllenhal, 1808), Agabus bipustulatus (Linnaeus, 1767), Agabus nevadensis Håkan Lindberg, 1939, Agabus wollastoni Sharp, 1882, Agabus melanarius Aubé, 1837, Agabus biguttatus (Olivier, 1795), Agabus binotatus Aubé, 1837, Agabus affinis (Paykull, 1798), Agabus unguicularis (Thomson, 1867), Agabus ramblae Millan & Ribera, 2001, Agabus conspersus (Marsham, 1802) and Agabus nebulosus (Forster, 1771). However two species, Agabus infuscatus Aubé, 1838 and Agabus adpressus Aubé, 1837, have developed a neo-XY system, with karyotypes comprising 21 pairs of autosomes and XY sex chromosomes (♂). No chromosomal differences have been detected between typical Agabus bipustulatus and Agabus bipustulatus var. solieri Aubé, 1837, nor have any been found between the three species of the Agabus bipustulatus complex (Agabus bipustulatus, Agabus nevadensis and Agabus wollastoni). The four species of Colymbetes Clairville, 1806, Colymbetes fuscus (Linnaeus, 1758), Colymbetes paykulli Erichson, 1837, Colymbetes piceus Klug, 1834 and Colymbetes striatus (Linnaeus, 1758) have karyotypes comprising 20 pairs of autosomes and sex chromosomes which are X0 (♂), XX (♀). Two of the species of Rhantus Dejean, 1833, Rhantus exsoletus (Forster, 1771) and Rhantus suturellus (Harris, 1828) have karyotypes comprising 20 pairs of autosomes and X0/XX sex chromosomes, but the other three species, Rhantus grapii (Gyllenhal, 1808), Rhantus frontalis (Marsham, 1802) and Rhantus suturalis (Macleay, 1825) have 22 pairs of

  9. The Small- and Medium-sized Enterprises Office (SME Office) at the European Medicines Agency.

    PubMed

    Carr, M

    2010-01-01

    On 15 December 2005, the European Medicines Agency (EMEA) launched an "SME Office" to provide financial and administrative assistance to micro-, small- and medium-sized enterprises (SMEs), with the aim of promoting innovation and the development of new human and veterinary medicinal products by SMEs. According to current EU definition of an SME, companies with fewer than 250 employees, and an annual turnover of not more than 50 million euro or an annual balance sheet total of not more than 43 million euro, are eligible for assistance from the SME Office. Incentives available from the EMEA for SMEs, include: Administrative and procedural assistance from SME Office within the Agency; Fee reductions (90%) for scientific advice and inspections; Fee exemptions for certain administrative services (excluding parallel distribution); Deferral of the fee payable for an application for marketing authorisation or related inspection until after the grant of the marketing authorisation; Conditional fee exemption where scientific advice followed and marketing application is unsuccessful; Assistance with translations of the product information documents. At the end of May 2009, more than 380 companies from 21 countries across the European Economic Area (EEA) had SME status assigned by the EMEA. The large majority of companies are developing medicinal products for human use, 16 are veterinary companies, 15 companies are developing products for both human and veterinary use and 38 are regulatory consultants. Since the SME initiative started the Agency has processed more than 130 requests for scientific advice with fee reductions totalling of 6.9 million euro. Regulatory assistance has been provided to more than 170 companies and 12 companies have benefited from the SME translation service. Stakeholders have acknowledged the significant role the SME Office now plays as a service provider. In the period between January 2006 and June 2009, 34 applications for marketing authorization

  10. Job Stress in the United Kingdom: Are Small and Medium-Sized Enterprises and Large Enterprises Different?

    PubMed

    Lai, Yanqing; Saridakis, George; Blackburn, Robert

    2015-08-01

    This paper examines the relationships between firm size and employees' experience of work stress. We used a matched employer-employee dataset (Workplace Employment Relations Survey 2011) that comprises of 7182 employees from 1210 private organizations in the United Kingdom. Initially, we find that employees in small and medium-sized enterprises experience lower level of overall job stress than those in large enterprises, although the effect disappears when we control for individual and organizational characteristics in the model. We also find that quantitative work overload, job insecurity and poor promotion opportunities, good work relationships and poor communication are strongly associated with job stress in the small and medium-sized enterprises, whereas qualitative work overload, poor job autonomy and employee engagements are more related with larger enterprises. Hence, our estimates show that the association and magnitude of estimated effects differ significantly by enterprise size.

  11. [Uncertainty in estimating short-term health effects of air pollution in small- and medium-size cities].

    PubMed

    Giannini, Simone; Zauli Sajani, Stefano; De Girolamo, Gianfranco; Goldoni, Carlo Alberto; Lauriola, Paolo

    2016-01-01

    Over the years, a growing number of small- and medium-size cities have been included in meta-analytic studies on short-term health effects of air pollution in order to increase the statistical power of these studies. This has produced an increase in the precision of meta-analytic estimates, but also a growing interest in city-specific results. As a consequence, relevant differences in the estimates have been frequently found, even for nearby cities with similar environmental and sociodemographic characteristics. This article aims at showing the variability of effect estimates for small- to medium-size cities in relation to the extent of the considered time frame, highlighting quantitatively the caution that must be taken in interpreting and communicating the results derived from short time series of data. The study was based on the analysis of the data from two cities in Emilia-Romagna Region (Northern Italy): Ravenna and Reggio Emilia.

  12. VOLTTRON™: Tech-to-Market Best-Practices Guide for Small- and Medium-Sized Commercial Buildings

    SciTech Connect

    Cort, Katherine A.; Haack, Jereme N.; Katipamula, Srinivas; Nicholls, Andrew K.

    2016-07-11

    VOLTTRON™ is an open-source distributed control and sensing platform developed by Pacific Northwest National Laboratory for the U.S. Department of Energy. It was developed to be used by the Office of Energy Efficiency and Renewable Energy to support transactive controls research and deployment activities. VOLTTRON is designed to be an overarching integration platform that could be used to bring together vendors, users, and developers and enable rapid application development and testing. The platform is designed to support modern control strategies, including the use of agent- and transaction-based controls. It also is designed to support the management of a wide range of applications, including heating, ventilation, and air-conditioning systems; electric vehicles; and distributed-energy and whole-building loads. This report was completed as part of the Building Technologies Office’s Technology-to-Market Initiative for VOLTTRON’s Market Validation and Business Case Development efforts. The report provides technology-to-market guidance and best practices related to VOLTTRON platform deployments and commercialization activities for use by entities serving small- and medium-sized commercial buildings. The report characterizes the platform ecosystem within the small- and medium-sized commercial building market and articulates the value proposition of VOLTTRON for three core participants in this ecosystem: 1) platform owners/adopters, 2) app developers, and 3) end-users. The report also identifies key market drivers and opportunities for open platform deployments in the small- and medium-sized commercial building market. Possible pathways to the market are described—laboratory testing to market adoption to commercialization. We also identify and address various technical and market barriers that could hinder deployment of VOLTTRON. Finally, we provide “best practice” tech-to-market guidance for building energy-related deployment efforts serving small- and

  13. Distinguishing between the bone fragments of medium-sized mammals and children. A histological identification method for archaeology.

    PubMed

    Cuijpers, Saddha A G F M

    2009-06-01

    In archaeology, it is not always possible to identify bone fragments. A novel approach was chosen to assess the potential of histology as an identification tool. Instead of studying a few bones of different categories from many species, this study concentrated on the diaphyses of long bones in four species of comparable size which are relevant to archaeology; young humans, pigs, sheep and goats, to broaden the insight into variations in diaphyseal bone structure within and between these species. A general difference in the primary bone structure was found between children older than one year and the three medium-sized mammals, namely lamellar vs. fibro-lamellar primary bone. Although, the diaphyseal bone structure of children below the age of one year also showed (developing) fibro-lamellar bone, its composition was distinctive from the medium-sized mammals. A difference in the secondary bone structure was also observed. Connecting (Volkmann's) canals, giving the secondary bone a reticular aspect, were seen in the medium-sized mammals but not in the young human long bones. To confirm the validity and applicability of these observed histological differences, a blind test was conducted on 14 diaphyseal fragments of identified long bones from archaeological sites. The results were very promising. All the bone fragments were correctly attributed using the difference in primary bone structure, even when the bone was severely degraded.

  14. Differential foraging preferences on seed size by rodents result in higher dispersal success of medium-sized seeds.

    PubMed

    Cao, Lin; Wang, Zhenyu; Yan, Chuan; Chen, Jin; Guo, Cong; Zhang, Zhibin

    2016-11-01

    Rodent preference for scatter-hoarding large seeds has been widely considered to favor the evolution of large seeds. Previous studies supporting this conclusion were primarily based on observations at earlier stages of seed dispersal, or on a limited sample of successfully established seedlings. Because seed dispersal comprises multiple dispersal stages, we hypothesized that differential foraging preference on seed size by animal dispersers at different dispersal stages would ultimately result in medium-sized seeds having the highest dispersal success rates. In this study, by tracking a large number of seeds for 5 yr, we investigated the effects of seed size on seed fates from seed removal to seedling establishment of a dominant plant Pittosporopsis kerrii (Icacinaceae) dispersed by scatter-hoarding rodents in tropical forest in southwest China. We found that small seeds had a lower survival rate at the early dispersal stage where more small seeds were predated at seed stations and after removal; large seeds had a lower survival rate at the late dispersal stage, more large seeds were recovered, predated after being cached, or larder-hoarded. Medium-sized seeds experienced the highest dispersal success. Our study suggests that differential foraging preferences by scatter-hoarding rodents at different stages of seed dispersal could result in conflicting selective pressures on seed size and higher dispersal success of medium-sized seeds.

  15. The spiny mouse (Acomys cahirinus) completes nephrogenesis before birth.

    PubMed

    Dickinson, Hayley; Walker, David W; Cullen-McEwen, Luise; Wintour, E Marelyn; Moritz, Karen

    2005-08-01

    The spiny mouse is relatively mature at birth. We hypothesized that like other organs, the kidney may be more developed in the spiny mouse at birth, than in other rodents. If nephrogenesis is complete before birth, the spiny mouse may provide an excellent model with which to study the effects of an altered intrauterine environment on renal development. Due to its desert adaptation, the spiny mouse may have a reduced cortex-to-medulla ratio but an equivalent total nephron number to the C57/BL mouse. Kidneys were collected from fetal and neonatal spiny mice and sectioned for gross examination of metanephric development. Kidneys were collected from adult spiny mice (10 wk of age), and glomerular number, volume, and cortex-to-medulla ratios were determined using unbiased stereology. Nephrogenesis is complete in spiny mouse kidneys before birth. Metanephrogenesis begins at approximately day 18, and by day 38 of a 40-day gestation, the nephrogenic zone is no longer present. Spiny mice have a significantly (P < 0.001) lower total nephron number compared with C57/BL mice, although the total glomerular volume is similar. The cortex-to-medulla ratio of the spiny mouse is significantly (P < 0.01) smaller. The spiny mouse is the first rodent species shown to complete nephrogenesis before birth. This makes it an attractive candidate for the study of fetal and neonatal kidney development and function. The reduced total nephron number and cortex-to-medulla ratio in the spiny mouse may contribute to its ability to highly concentrate its urine under stressful conditions (i.e., dehydration).

  16. 78 FR 51746 - Trade Barriers That U.S. Small and Medium-sized Enterprises Perceive as Affecting Exports to the...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-08-21

    ... COMMISSION Trade Barriers That U.S. Small and Medium-sized Enterprises Perceive as Affecting Exports to the... Barriers that U.S. Small and Medium-sized Enterprises Perceive as Affecting Exports to the European Union... ). Persons with mobility impairments who will need special assistance in gaining access to the...

  17. 78 FR 45969 - Trade Barriers That U.S. Small and Medium-Sized Enterprises Perceive as Affecting Exports to the...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-07-30

    ... COMMISSION Trade Barriers That U.S. Small and Medium-Sized Enterprises Perceive as Affecting Exports to the... and Medium- sized Enterprises Perceive as Affecting Exports to the European Union. DATES: September 13... ). Persons with mobility impairments who will need special assistance in gaining access to the...

  18. 78 FR 66950 - Trade Barriers That U.S. Small and Medium-Sized Enterprises Perceive as Affecting Exports to the...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-11-07

    ... COMMISSION Trade Barriers That U.S. Small and Medium-Sized Enterprises Perceive as Affecting Exports to the... ). Persons with mobility impairments who will need special assistance in gaining access to the Commission... prepare a report that catalogs trade barriers that U.S. small and medium-sized enterprises (SMEs)...

  19. Discriminating between Medium-Sized Tridactyl Trackmakers: Tracking Ornithopod Tracks in the Base of the Cretaceous (Berriasian, Spain)

    PubMed Central

    Castanera, Diego; Pascual, Carlos; Razzolini, Novella L.; Vila, Bernat; Barco, José L.; Canudo, José I.

    2013-01-01

    Background Recent work on the Jurassic-Cretaceous transition of the Iberian Range (Spain) has opened a new window onto the interpretation of the trackmakers of some medium-sized tridactyl tracks. The ichnotaxon Therangospodus oncalensis has been described in the Huérteles Formation (Berriasian) and is one of the classical tracks from the area assigned to medium-sized theropods. Methodology/Principal Findings A review of the type locality of Therangospodus oncalensis (Fuentesalvo tracksite) and other tracksites from the Huérteles Formation (Berriasian) has yielded new information on the morphology, gait and trackmaker identity of the aforementioned ichnospecies. The new data suggest that the trackmaker is an ornithopod rather than a theropod on the basis of the length/width ratio, the anterior triangle length-width ratio, the short steps, the round to quadrangular heel pad impression and the probable manus impressions. Conclusions/Significance T. oncalensis shows similarities with various tracks from the Berriasian of Europe assigned to Iguanodontipus. The ichnotaxonomical status of this ichnospecies is here considered as Iguanodontipus? oncalensis due to the current state of knowledge of the ichnotaxonomy of medium-sized ornithopod tracks. This reassessment of I? oncalensis also has two significant implications for the palaeoecology of the faunas during the deposition of the Huérteles Formation: 1- the high number and percentage of theropod tracks would be lower than previous papers have suggested. 2- the gregarious behaviour described in the type locality (Fuentesalvo) would be among ornithopods instead of theropods. PMID:24303075

  20. Intra-Arterial Angiolymphoid Hyperplasia with Eosinophilia: A Rare Case Report of Peripheral Medium Sized Muscular Artery Involvement.

    PubMed

    Amin, Ashima; Umashankar, T; Dsouza, Chryselle Olive

    2015-08-01

    Angiolymphoid hyperplasia with eosinophilia (ALHE) is an uncommon benign vasoproliferative disease with distinct clinical and histopathological features. The most common clinical presentation is dermal and subcutaneous painless nodules in the head and neck region. The involvement of medium sized peripheral muscular artery is uncommon. It predominantly affects Caucasian adults during the third and fourth decades, but is also known to occur in Asians and it very rarely occurs in children. We here by present a case of intravascular ALHE in a 46-year-old female presenting with subcutaneous forearm nodule clinically diagnosed as ulnar artery thrombosis.

  1. 50 CFR 648.235 - Spiny dogfish possession and landing restrictions.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 50 Wildlife and Fisheries 12 2014-10-01 2014-10-01 false Spiny dogfish possession and landing... Management Measures for the Spiny Dogfish Fishery § 648.235 Spiny dogfish possession and landing restrictions. (a) Possession limit. Vessels issued a valid Federal spiny dogfish permit under § 648.4(a)(11)...

  2. 50 CFR 648.239 - Spiny dogfish framework adjustments to management measures.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 50 Wildlife and Fisheries 12 2013-10-01 2013-10-01 false Spiny dogfish framework adjustments to... UNITED STATES Management Measures for the Spiny Dogfish Fishery § 648.239 Spiny dogfish framework... consistent with the goals and objectives of the Spiny Dogfish FMP. (1) Adjustment process. After the...

  3. 50 CFR 648.239 - Spiny dogfish framework adjustments to management measures.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 50 Wildlife and Fisheries 12 2014-10-01 2014-10-01 false Spiny dogfish framework adjustments to... UNITED STATES Management Measures for the Spiny Dogfish Fishery § 648.239 Spiny dogfish framework... consistent with the goals and objectives of the Spiny Dogfish FMP. (1) Adjustment process. After the...

  4. 50 CFR 648.235 - Spiny dogfish possession and landing restrictions.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 50 Wildlife and Fisheries 12 2012-10-01 2012-10-01 false Spiny dogfish possession and landing... Management Measures for the Spiny Dogfish Fishery § 648.235 Spiny dogfish possession and landing restrictions. (a) Quota Period 1. From May 1 through October 31, vessels issued a valid Federal spiny...

  5. 50 CFR 648.235 - Spiny dogfish possession and landing restrictions.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 50 Wildlife and Fisheries 12 2013-10-01 2013-10-01 false Spiny dogfish possession and landing... Management Measures for the Spiny Dogfish Fishery § 648.235 Spiny dogfish possession and landing restrictions. (a) Quota period 1. From May 1 through October 31, vessels issued a valid Federal spiny...

  6. 50 CFR 648.239 - Spiny dogfish framework adjustments to management measures.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 50 Wildlife and Fisheries 12 2012-10-01 2012-10-01 false Spiny dogfish framework adjustments to... UNITED STATES Management Measures for the Spiny Dogfish Fishery § 648.239 Spiny dogfish framework... consistent with the goals and objectives of the Spiny Dogfish FMP. (1) Adjustment process. After the...

  7. 50 CFR 648.239 - Spiny dogfish framework adjustments to management measures.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 50 Wildlife and Fisheries 10 2011-10-01 2011-10-01 false Spiny dogfish framework adjustments to... UNITED STATES Management Measures for the Spiny Dogfish Fishery § 648.239 Spiny dogfish framework... consistent with the goals and objectives of the Spiny Dogfish FMP. (1) Adjustment process. After the...

  8. A biological and chemical characterization strategy for small and medium-sized industries connected to municipal sewage treatment plants

    SciTech Connect

    Tarkpea, M.; Eklund, B.; Andren, C.; Gravenfors, E.; Kukulska, Z.

    1998-02-01

    A cost-effective strategy for the characterization of wastewater from small and medium-sized industries is described. A mobile laboratory, equipped for performing on-site biological tests, was established near wastewater treatment facilities in two cities in Sweden for 1 week each in November 1992 and November 1993. The biological and chemical characterization was done on 24-h samples from 29 industries representing 12 types of activity with a bias toward the surface treatment and graphics industries. The biological testing program included a modified nitrification test, the Microtox test, and a modified growth inhibition test using Selenastrum capricornutum (an alga test). A Ceriodaphnia dubia (crustacean) test was also used for some industries. Different chemical assessments, aimed at indicating toxic, persistent, and bioaccumulating substances, were chosen for each industry on the basis of information they provided. Results show that sampling period and time are important factors to consider when designing a characterization strategy. Twenty-four-hour sampling is preferred to weekly sampling because highly toxic emissions of short duration that are detrimental to the biological treatment plant may occur. Variability in emissions was shown in this study but would not have been detected by a study based on weekly sampling. The strategy developed in this study was shown to be both a cost-effective and efficient tool for characterizing effluents from small and medium-sized industries.

  9. A qualitative study of pandemic influenza preparedness among small and medium-sized businesses in New York City.

    PubMed

    Burton, Deron C; Confield, Evan; Gasner, Mary Rose; Weisfuse, Isaac

    2011-10-01

    Small businesses need to engage in continuity planning to assure delivery of goods and services and to sustain the economy during an influenza pandemic. This is especially true in New York City, where 98 per cent of businesses have fewer than 100 employees. It was an objective therefore, to determine pandemic influenza business continuity practices and strategies suitable for small and medium-sized NYC businesses. The study design used focus groups, and the participants were owners and managers of businesses with fewer than 500 employees in New York City. The main outcome measures looked for were the degree of pandemic preparedness, and the feasibility of currently proposed business continuity strategies. Most participants reported that their businesses had no pandemic influenza plan. Agreement with feasibility of specific business continuity strategies was influenced by the type of business represented, cost of the strategy, and business size. It was concluded that recommendations for pandemic-related business continuity plans for small and medium-sized businesses should be tailored to the type and size of business and should highlight the broad utility of the proposed strategies to address a range of business stressors.

  10. The role of fcc tetrahedral subunits in the phase behavior of medium sized Lennard-Jones clusters.

    PubMed

    Saika-Voivod, Ivan; Poon, Louis; Bowles, Richard K

    2010-08-21

    The free energy of a 600-atom Lennard-Jones cluster is calculated as a function of surface and bulk crystallinity in order to study the structural transformations that occur in the core of medium sized clusters. Within the order parameter range studied, we find the existence of two free energy minima at temperatures near freezing. One minimum, at low values of both bulk and surface order, belongs to the liquid phase. The second minimum exhibits a highly ordered core with a disordered surface and is related to structures containing a single fcc-tetrahedral subunit, with an edge length of seven atoms (l=7), located in the particle core. At lower temperatures, a third minimum appears at intermediate values of the bulk order parameter which is shown to be related to the formation of multiple l=6 tetrahedra in the core of the cluster. We also use molecular dynamics simulations to follow a series of nucleation events and find that the clusters freeze to structures containing l=5, 6, 7, and 8 sized tetrahedra as well as those containing no tetrahedral units. The structural correlations between bulk and surface order with the size of the tetrahedral units in the cluster core are examined. Finally, the relationships between the formation of fcc tetrahedral subunits in the core, the phase behavior of medium sized clusters and the nucleation of noncrystalline global structures such as icosahedra and decahedra are discussed.

  11. Estimated performance of an adaptive trailing-edge device aimed at reducing fuel consumption on a medium-size aircraft

    NASA Astrophysics Data System (ADS)

    Diodati, Gianluca; Concilio, Antonio; Ricci, Sergio; De Gaspari, Alessandro; Huvelin, Fabien; Dumont, Antoine; Godard, Jean-Luc

    2013-03-01

    This paper deals with the estimation of the performance of a medium-size aircraft (3-hour flight range) equipped with an adaptive trailing edge device (ATED) that runs span-wise from the wing root in the flap zone and extends chord-wise for a limited percentage of the MAC. Computations are calculated referring to the full wing and do not refer to the complete aircraft configuration. Aerodynamic computations, taking into account ideal shapes, have been performed by using both Euler and Navier- Stokes method in order to extract the wing polars for the reference and the optimal wing, implementing an ATED, deflected upwards and downwards. A comparison of the achieved results is discussed. Considering the shape domain, a suitable interpolation procedure has been set up to obtain the wing polar envelop of the adaptive wing, intended as the set of "best" values, picked by each different polar. At the end, the performances of the complete reference and adaptive wing are computed and compared for a symmetric, centered, leveled and steady cruise flight for a medium size aircraft. A significant fuel burn reduction estimate or, alternatively, an increased range capability is demonstrated, with margins of further improvements. The research leading to these results has gratefully received funding from the European Union Seventh Framework Programme (FP7/2007- 2013) under Grant Agreement n° 284562.

  12. [Cultivation strategy and path analysis on big brand Chinese medicine for small and medium-sized enterprises].

    PubMed

    Wang, Yong-Yan; Yang, Hong-Jun

    2014-03-01

    Small and medium-sized enterprises (SMEs) are important components in Chinese medicine industry. However, the lack of big brand is becoming an urgent problem which is critical to the survival of SMEs. This article discusses the concept and traits of Chinese medicine of big brand, from clinical, scientific and market value three aspects. Guided by market value, highlighting clinical value, aiming at the scientific value improvement of big brand cultivation, we put forward the key points in cultivation, aiming at obtaining branded Chinese medicine with widely recognized efficacy, good quality control system and mechanism well explained and meanwhile which can bring innovation improvement to theory of Chinese medicine. According to the characters of SMEs, we hold a view that to build multidisciplinary research union could be considered as basic path, and then, from top-level design, skill upgrading and application three stages to probe the implementation strategy.

  13. Development of Proof-of-Concept Units for the Advanced Medium-Sized Mobile Power Sources (AMMPS) Program

    SciTech Connect

    Andriulli, JB

    2002-04-03

    The purpose of this report is to document the development of the proof-of-concept units within the Advanced Medium-sized Mobile Power Sources (AMMPS) program. The design used a small, lightweight diesel engine, a permanent magnet alternator, power electronics and digital controls as outlined in the philosophy detailed previously. One small proof-of-concept unit was completed and delivered to the military. The unit functioned well but was not optimized at the time of delivery to the military. A tremendous amount of experience was gained during this phase that can be used in the development of any follow-on AMMPS production systems. Lessons learned and recommendations for follow-on specifications are provided. The unit demonstrated that significant benefits are possible with the new design philosophy. Trade-offs will have to be made but many of the advantages appear to be within the technical grasp of the market.

  14. Occupational Safety and Health Conditions Aboard Small- and Medium-Size Fishing Vessels: Differences among Age Groups.

    PubMed

    Zytoon, Mohamed A; Basahel, Abdulrahman M

    2017-02-24

    Although marine fishing is one of the most hazardous occupations, research on the occupational safety and health (OSH) conditions aboard marine fishing vessels is scarce. For instance, little is known about the working conditions of vulnerable groups such as young and aging fishermen. The objective of the current paper is to study the OSH conditions of young and aging fishermen compared to middle-aged fishermen in the small- and medium-size (SM) marine fishing sector. A cross-sectional study was designed, and 686 fishermen working aboard SM fishing vessels were interviewed to collect information about their safety and health. The associations of physical and psychosocial work conditions with safety and health outcomes, e.g., injuries, illnesses and job satisfaction, are presented. The results of the current study can be utilized in the design of effective accident prevention and OSH training programs for the three age groups and in the regulation of working conditions aboard fishing vessels.

  15. Occupational Safety and Health Conditions Aboard Small- and Medium-Size Fishing Vessels: Differences among Age Groups

    PubMed Central

    Zytoon, Mohamed A.; Basahel, Abdulrahman M.

    2017-01-01

    Although marine fishing is one of the most hazardous occupations, research on the occupational safety and health (OSH) conditions aboard marine fishing vessels is scarce. For instance, little is known about the working conditions of vulnerable groups such as young and aging fishermen. The objective of the current paper is to study the OSH conditions of young and aging fishermen compared to middle-aged fishermen in the small- and medium-size (SM) marine fishing sector. A cross-sectional study was designed, and 686 fishermen working aboard SM fishing vessels were interviewed to collect information about their safety and health. The associations of physical and psychosocial work conditions with safety and health outcomes, e.g., injuries, illnesses and job satisfaction, are presented. The results of the current study can be utilized in the design of effective accident prevention and OSH training programs for the three age groups and in the regulation of working conditions aboard fishing vessels. PMID:28245578

  16. Environmental Management in Small and Medium-Sized Companies: An Analysis from the Perspective of the Theory of Planned Behavior

    PubMed Central

    Sánchez-Medina, Agustín J.; Romero-Quintero, Leonardo; Sosa-Cabrera, Silvia

    2014-01-01

    In the business context, concern for the environment began to develop when pressure from the public administration and environmental awareness groups raised the specific requirements for companies. The Theory of Planned Behavior considers that people's conduct is determined by the intention of carrying out a certain behavior. Thus, the individual's intent is determined by three factors related to the desired outcome of the behavior: the Personal Attitude toward the Results, the Perceived Social Norms, and the Perceived Behavioral Control over the action. Therefore, the objectives of this paper are to clarify the attitudes of the managers of Canarian small and medium-sized companies about taking environmental measures, and try to demonstrate whether there is a relationship between the proposed factors and the intention to take these measures. PMID:24533094

  17. Environmental management in small and medium-sized companies: an analysis from the perspective of the theory of planned behavior.

    PubMed

    Sánchez-Medina, Agustín J; Romero-Quintero, Leonardo; Sosa-Cabrera, Silvia

    2014-01-01

    In the business context, concern for the environment began to develop when pressure from the public administration and environmental awareness groups raised the specific requirements for companies. The Theory of Planned Behavior considers that people's conduct is determined by the intention of carrying out a certain behavior. Thus, the individual's intent is determined by three factors related to the desired outcome of the behavior: the Personal Attitude toward the Results, the Perceived Social Norms, and the Perceived Behavioral Control over the action. Therefore, the objectives of this paper are to clarify the attitudes of the managers of Canarian small and medium-sized companies about taking environmental measures, and try to demonstrate whether there is a relationship between the proposed factors and the intention to take these measures.

  18. Molecular (global) and atom-in-cluster (local) polarizabilities of medium-size gold nanoclusters: isomer structure effects

    NASA Astrophysics Data System (ADS)

    Rodríguez, Juan I.; Baltazar-Méndez, Maria I.; Autschbach, Jochen; Castillo-Alvarado, F. L.

    2013-06-01

    In this work, we extend our recent study [J.I. Rodríguez, J. Autschbach, F.L. Castillo-Alvarado, M.I. Baltazar-Méndez, J. Chem. Phys. 135, 034109 (2011)] to quantify the isomer structure effects on the atom-in-cluster polarizabilities of medium size gold clusters Au ( n = 6, 12, 20, 34, 54). For three isomers for each cluster size, a density functional perturbation theory calculation was performed to compute the cluster polarizability and the polarizability of each atom in the cluster using Bader's "quantum theory of atoms in molecules" formalism. The cluster polarizability tensor is expressed as a sum of the atom-in-cluster atomic tensors. We found that the strong quadratic correlation ( R 2 = 0.98) in the isotropic polarizability of atoms in the cluster and their distance to the cluster center of mass reported before holds independently of the cluster structure.

  19. Patterns and Pathways of Evolving Catchment Response in a Medium-Sized Mediterranean Catchment on a Millennium Scale

    NASA Astrophysics Data System (ADS)

    van Beek, L. P. H.; Bierkens, M. F. P.

    2012-04-01

    The meso-scale landscape dynamics model, CALEROS, has been developed to simulate the interactions between climate, soil production and erosion, vegetation and land use on geomorphological to human time scales in Mediterranean environments. Starting from an initial landscape consisting of a DTM, soil distribution and underlying lithology, the landscape is free to develop in response to the imposed climate variability and seismicity. In addition to changes in soil distribution and bedrock lowering, this includes the establishment of vegetation as conditioned by a selection of plant functional types and, optionally, population and land use dynamics as conditioned by land use scenarios specifying technological and dietary constraints for different periods. As such CALEROS is well-suited to investigate the relative impacts of climate, land cover and human activities on the hydrological catchment response and the associated sediment fluxes due to soil erosion and mass movements. Here we use CALEROS to i) investigate the redistribution of water and sediment across the landscape in a medium-sized Mediterranean catchment (Contrada Maddalena; ~14km2, Calabria, Italy) and ii) to establish patterns of co-evolution in soil properties and vegetation under pristine and anthropogenically impacted conditions on a millennium-scale. Using summary statistics to describe the emergent properties and to verify them against observations, we then delineate areas of uniform morphology and describe the various pathways of development. This information allows us to identify elements of consistent hydrological response and the associated transfer of material across different scales. It also provides essential information on essential feedbacks and the resulting convergence or divergence in landscape development under the impact of climatic or seismic events or human intervention. Although the results are evidently conditioned by the physiographic setting of the study area and by the

  20. The Alignment System for a Medium-Sized Schwarzschild-Couder Telescope Prototype for the Cherenkov Telescope Array

    NASA Astrophysics Data System (ADS)

    Ribeiro, Deivid; Humensky, Brian; Nieto, Daniel; V Vassiliev Group in UCLA division of Astronomy and Astrophysics, P Kaaret Group at Iowa University Department of Physics and Astronomy, CTA Consortium

    2016-01-01

    The Cherenkov Telescope Array (CTA) is an international project for a next-generation ground-based gamma-ray observatory. CTA, conceived as an array of tens of imaging atmospheric Cherenkov telescopes, comprising small, medium and large-size telescopes, is aiming to improve on the sensitivity of current-generation experiments by an order of magnitude and provide energy coverage from 20 GeV to more than 300 TeV. The Schwarzschild-Couder design is a candidate 9-m diameter medium-sized telescope featuring a novel aplanatic two-mirror optical design capable of a wide field of view with significantly improved imaging resolution as compared to the traditional Davies-Cotton optical design. Achieving this imaging resolution imposes strict mirror alignment requirements that necessitate a sophisticated alignment system. This system uses a collection of position sensors between panels to determine the relative position of adjacent panels; each panel is mounted on a Stewart platform to allow motion control with six degrees of freedom, facilitating the alignment of the optical surface for the segmented primary and secondary mirrors. Alignments of the primary and secondary mirrors and the camera focal plane with respect to each other are performed utilizing a set of CCD cameras which image LEDs placed on the mirror panels to measure relative translation, and custom-built auto-collimators to measure relative tilt between the primary and secondary mirrors along the optical axis of the telescope. In this contribution we present the status of the development of the SC optical alignment system, soon to be materialized in a full-scale prototype SC medium-size telescope (pSCT) at the Fred Lawrence Whipple Observatory in southern Arizona.

  1. Coordination of planar cell polarity pathways through Spiny-legs

    PubMed Central

    Ambegaonkar, Abhijit A; Irvine, Kenneth D

    2015-01-01

    Morphogenesis and physiology of tissues and organs requires planar cell polarity (PCP) systems that orient and coordinate cells and their behaviors, but the relationship between PCP systems has been controversial. We have characterized how the Frizzled and Dachsous-Fat PCP systems are connected through the Spiny-legs isoform of the Prickle-Spiny-legs locus. Two different components of the Dachsous-Fat system, Dachsous and Dachs, can each independently interact with Spiny-legs and direct its localization in vivo. Through characterization of the contributions of Prickle, Spiny-legs, Dachsous, Fat, and Dachs to PCP in the Drosophila wing, eye, and abdomen, we define where Dachs-Spiny-legs and Dachsous-Spiny-legs interactions contribute to PCP, and provide a new understanding of the orientation of polarity and the basis of PCP phenotypes. Our results support the direct linkage of PCP systems through Sple in specific locales, while emphasizing that cells can be subject to and must ultimately resolve distinct, competing PCP signals. DOI: http://dx.doi.org/10.7554/eLife.09946.001 PMID:26505959

  2. Impact of Platelet-Rich Plasma on Arthroscopic Repair of Small- to Medium-Sized Rotator Cuff Tears

    PubMed Central

    Holtby, Richard; Christakis, Monique; Maman, Eran; MacDermid, Joy C.; Dwyer, Tim; Athwal, George S.; Faber, Kenneth; Theodoropoulos, John; Woodhouse, Linda J.; Razmjou, Helen

    2016-01-01

    Background: Increased interest in using platelet-rich plasma (PRP) as an augment to rotator cuff repair warrants further investigation, particularly in smaller rotator cuff tears. Purpose: To examine the effectiveness of PRP application in improving perioperative pain and function and promoting healing at 6 months after arthroscopic repair of small- or medium-sized rotator cuff tears. Study Design: Randomized controlled trial; Level of evidence, 1. Methods: This was a double-blinded randomized controlled trial of patients undergoing arthroscopic repair of partial- or full-thickness rotator cuff tears of up to 3 cm who were observed for 6 months. Patients were randomized to either repair and PRP application (study group) or repair only (control group) groups. The patient-oriented outcome measures utilized were the visual analog scale (VAS), the Short Western Ontario Rotator Cuff Index (ShortWORC), the American Shoulder and Elbow Surgeons (ASES) form, and the Constant-Murley Score (CMS). Range of motion (ROM) and inflammatory and coagulation markers were measured before and after surgery. Magnetic resonance imaging was used at 6 months to assess retear and fatty infiltration rate. Results: Eighty-two patients (41 males) with a mean age of 59 ± 8 years were enrolled; 41 patients were included in each group. Both the PRP and control groups showed a significant improvement in their pain level based on the VAS within the first 30 days (P < .0001), with the PRP group reporting less pain than the control group (P = .012), which was clinically significantly different from days 8 through 11. The PRP group reported taking less painkillers (P = .026) than the control group within the first 30 days. All outcome measure scores and ROM improved significantly after surgery (P < .0001), with no between-group differences. No differences were observed between groups in inflammatory or coagulation marker test results (P > .05), retear (14% vs 18% full retear; P = .44), or fatty

  3. Development of the ACS+OPC UA based control system for a CTA medium size telescope prototype

    NASA Astrophysics Data System (ADS)

    Behera, Bagmeet; Oya, Igor; Birsin, Emrah; Köppel, Hendryk; Melkumyan, David; Schlenstedt, Stefan; Schmidt, Torsten; Schwanke, Ullrich; Wegner, Peter; Wiesand, Stephan; Winde, Michael

    2012-09-01

    The Cherenkov Telescope Array (CTA) is the next generation Very High Energy (VHE, defined as > 50GeV to several 100TeV) telescope facility, currently in the design and prototyping phase, and expected to come on-line around 2016. The array would have both a Northern and Southern hemisphere site, together delivering nearly complete sky coverage. The CTA array is planned to have ~100 telescopes of several different sizes to fulfill the sensitivity and energy coverage needs. Each telescope has a number of subsystems with varied hardware and control mechanisms; a drive system that gets commands and inputs via OPC UA (OPC Unified Architecture), mirror alignment systems based on XBee/ZigBee protocol and/or CAN bus, weather monitor accessed via serial/Ethernet ports, CCD cameras for calibration, Cherenkov camera, and the data read out electronics, etc. Integrating the control and data-acquisitions of such a distributed heterogeneous system calls for a framework that can handle such a multi-platform, multi-protocol scenario. The CORBA based ALMA Common software satisfies these needs very well and is currently being evaluated as the base software for developing the control system for CTA. A prototype for a Medium Size Telescope (MST, ~12m) is being developed and will be deployed in Berlin, by end of 2012. We present the development being carried out to integrate and control the various hardware subsystems of this MST prototype using ACS.

  4. Analyzing the efficiency of small and medium-sized enterprises of a national technology innovation research and development program.

    PubMed

    Park, Sungmin

    2014-01-01

    This study analyzes the efficiency of small and medium-sized enterprises (SMEs) of a national technology innovation research and development (R&D) program. In particular, an empirical analysis is presented that aims to answer the following question: "Is there a difference in the efficiency between R&D collaboration types and between government R&D subsidy sizes?" Methodologically, the efficiency of a government-sponsored R&D project (i.e., GSP) is measured by Data Envelopment Analysis (DEA), and a nonparametric analysis of variance method, the Kruskal-Wallis (KW) test is adopted to see if the efficiency differences between R&D collaboration types and between government R&D subsidy sizes are statistically significant. This study's major findings are as follows. First, contrary to our hypothesis, when we controlled the influence of government R&D subsidy size, there was no statistically significant difference in the efficiency between R&D collaboration types. However, the R&D collaboration type, "SME-University-Laboratory" Joint-Venture was superior to the others, achieving the largest median and the smallest interquartile range of DEA efficiency scores. Second, the differences in the efficiency were statistically significant between government R&D subsidy sizes, and the phenomenon of diseconomies of scale was identified on the whole. As the government R&D subsidy size increases, the central measures of DEA efficiency scores were reduced, but the dispersion measures rather tended to get larger.

  5. [The certification of advanced therapy medicinal products. A quality label for product development in small and medium-sized enterprises].

    PubMed

    Berger, A; Schüle, S; Flory, E

    2011-07-01

    Advanced therapy medicinal products (ATMPs) are gene therapy, cell therapy, and tissue engineered products. To gain access to the market within the European Union, ATMPs must be authorized by the European Commission (EC). Especially for small and medium-sized enterprises (SMEs), the European centralized procedure of marketing authorization that is conducted by the European Medicines Agency (EMA) constitutes a major challenge, because SMEs often have little experience with regulatory procedures and many have limited financial possibilities. To tackle these challenges, a certification procedure exclusively for SMEs and their ATMP development was introduced by the EC. Independently from a marketing authorization application, development and/or production processes can be certified. An issued certificate demonstrates that the respective process meets the current regulatory and scientific requirements of the EMA, representing a valuable milestone for putative investors and licensees. This article highlights the background, the detailed procedure, the minimum requirements, as well as the costs of certification, while giving further noteworthy guidance for interested parties.

  6. Risk determinants of small and medium-sized manufacturing enterprises (SMEs) - an exploratory study in New Zealand

    NASA Astrophysics Data System (ADS)

    Islam, Ariful; Tedford, Des

    2012-08-01

    The smooth running of small and medium-sized manufacturing enterprises (SMEs) presents a significant challenge irrespective of the technological and human resources they may have at their disposal. SMEs continuously encounter daily internal and external undesirable events and unwanted setbacks to their operations that detract from their business performance. These are referred to as `disturbances' in our research study. Among the disturbances, some are likely to create risks to the enterprises in terms of loss of production, manufacturing capability, human resource, market share, and, of course, economic losses. These are finally referred to as `risk determinant' on the basis of their correlation with some risk indicators, which are linked to operational, occupational, and economic risks. To deal with these risk determinants effectively, SMEs need a systematic method of approach to identify and treat their potential effects along with an appropriate set of tools. However, initially, a strategic approach is required to identify typical risk determinants and their linkage with potential business risks. In this connection, we conducted this study to explore the answer to the research question: what are the typical risk determinants encountered by SMEs? We carried out an empirical investigation with a multi-method research approach (a combination of a questionnaire-based mail survey involving 212 SMEs and five in-depth case studies) in New Zealand. This paper presents a set of typical internal and external risk determinants, which need special attention to be dealt with to minimize operational risks of an SME.

  7. Pediatric Oncology Clinic Care Model: Achieving Better Continuity of Care for Patients in a Medium-sized Program.

    PubMed

    Johnston, Donna L; Halton, Jacqueline; Bassal, Mylène; Klaassen, Robert J; Mandel, Karen; Ramphal, Raveena; Simpson, Ewurabena; Peckan, Li

    2016-10-25

    Providing the best care in both the inpatient and outpatient settings to pediatric oncology patients is all programs goal. Using continuous improvement methodologies, we changed from a solely team-based physician care model to a hybrid model. All patients were assigned a dedicated oncologist. There would then be 2 types of weeks of outpatient clinical service. A "Doc of the Day" week where each oncologist would have a specific day in clinic when their assigned patients would be scheduled, and then a "Doc of the Week" week where one physician would cover clinic for the week. Patient satisfaction surveys done before and 14 months after changing the model of care showed that patients were very satisfied with the care they received in both models. A questionnaire to staff 14 months after changing showed that the biggest effect was increased continuity of care, followed by more efficient clinic workflow and increased consistency of care. Staff felt it provided better planning and delivery of care. A hybrid model of care with a primary physician for each patient and assigned clinic days, alternating with weeks of single physician coverage is a feasible model of care for a medium-sized pediatric oncology program.

  8. Boys who pee the farthest have a large hollow head, a thin skin, and medium-size manhood

    NASA Astrophysics Data System (ADS)

    Attinger, Daniel; Lee, Vincent

    2016-11-01

    Following a recent trend of scientific studies on artwork, we study here the thermodynamics of a jetting thermometer made of ceramic, related to the Chinese tea culture. The thermometer represents a boy who "urinates" shortly after hot water is poured onto his head. Long jetting distance indicates if the water temperature is hot enough to brew tea. Here, a thermofluid model describes the jetting phenomenon of that pee-pee boy. The study demonstrates how thermal expansion of an interior air pocket causes jetting. The validity of assumptions underlying the Hagen-Poiseuille flow is discussed for urethra of finite length. A thermodynamic potential is shown to define maximum jetting velocity. Seven optimization criteria to maximize jetting distance are provided, including two dimensionless numbers. The dimensionless numbers are obtained by comparing the time scales of the internal pressure buildup due to heating, with that of pressure relief due to jetting. Optimization results show that longer jets are produced by large individuals, with low body mass index, with a boyhood of medium size inclined at an angle π/4. Analogies are drawn with pissing contests among humans and lobsters. The study ends by noting similitudes of working principle between that politically incorrect thermometer and Galileo Galilei's thermoscope.

  9. Study on recent execution of overall evaluation bidding method in small and medium-sized regional local governments

    NASA Astrophysics Data System (ADS)

    Fujishima, Hirohide; Yanase, Norihiko

    About 70% of local governments in Japan, endeavored to introduce overall evaluation bidding method for their public works in 2011 and each authority ordered one or some projects in according to the new bidding process. That is, their enforcement was an only trial level and they say that the reason why is long-term procedure and heavily administrative load of the system. The author think that such burden has relationship of human affairs of local govern ments, practical problems on kinds and price of constructions and the officers' experience on the new bidding method. The aim of this study is to analyze such problems among the officers' profession, posts and experience of administrative matter by statistical data, questionnaire and hearing to the officers. The result could indicate that a group of small local governments uses the method appropriately and that another group of medium-sized rejects to increase more contracts in according to the new bidding system because of unbalance between the stuffs' ability and order quantity of public works.

  10. Impact of local urban design and traffic restrictions on air quality in a medium-sized town.

    PubMed

    Acero, J A; Simon, A; Padro, A; Santa Coloma, O

    2012-01-01

    Traffic is the major air pollution source in most urban areas. Nowadays, most of the strategies carried out to improve urban air quality are focused on reducing traffic emissions. Nevertheless, acting locally on urban design can also reduce levels of air pollutants. In this paper, both strategies are studied in several scenarios for a medium-sized town of the Basque Country (Spain). Two main actions are analysed in order to reduce traffic emissions: (1) minor extension ofa pre-existing low emission zone (LEZ); (2) substitution of 10% of passenger cars that are older than 5 years by hybrid and electric vehicles. Regarding local urban design, three alternatives for the development of one side of a street canyon are considered: (1) a park with trees; (2) an open space without obstacles; (3) a building. Two different urban traffic dispersion models are used to calculate the air quality scenarios: PROKAS (Gaussian&box) to analyse the reduction of traffic emissions in the whole urban area and WinMISKAM (CFD) to evaluate specific urban designs. The results show the effectiveness of the analysed actions. On one hand, the definition of a small LEZ, as well as the introduction in 2015 of vehicles with new technology (hybrid and electric), results in minor impacts on PM10 and NO2 ambient concentrations. On the other hand, local urban design can cause significant variation in spatial distribution ofpollutant concentrations emitted inside street canyons. Consequently, urban planners should consider all these aspects when dealing with urban air pollution control.

  11. On the variational computation of a large number of vibrational energy levels and wave functions for medium-sized molecules

    NASA Astrophysics Data System (ADS)

    Mátyus, Edit; Šimunek, Ján; Császár, Attila G.

    2009-08-01

    In a recent publication [J. Chem. Phys. 127, 084102 (2007)], the nearly variational DEWE approach (DEWE denotes Discrete variable representation of the Watson Hamiltonian using the Eckart frame and an Exact inclusion of a potential energy surface expressed in arbitrarily chosen coordinates) was developed to compute a large number of (ro)vibrational eigenpairs for medium-sized semirigid molecules having a single well-defined minimum. In this publication, memory, CPU, and hard disk usage requirements of DEWE, and thus of any DEWE-type approach, are carefully considered, analyzed, and optimized. Particular attention is paid to the sparse matrix-vector multiplication, the most expensive part of the computation, and to rate-determining steps in the iterative Lanczos eigensolver, including spectral transformation, reorthogonalization, and restart of the iteration. Algorithmic improvements are discussed in considerable detail. Numerical results are presented for the vibrational band origins of the C12H4 and C12H2D2 isotopologues of the methane molecule. The largest matrix handled on a personal computer during these computations is of the size of (4•108)×(4•108). The best strategy for determining vibrational eigenpairs depends largely on the actual details of the required computation. Nevertheless, for a usual scenario requiring a large number of the lowest eigenpairs of the Hamiltonian matrix the combination of the thick-restart Lanczos method, shift-fold filtering, and periodic reorthogonalization appears to result in the computationally most feasible approach.

  12. Conducting Creativity Brainstorming Sessions in Small and Medium-Sized Enterprises Using Computer-Mediated Communication Tools

    NASA Astrophysics Data System (ADS)

    Murthy, Uday S.

    A variety of Web-based low cost computer-mediated communication (CMC) tools are now available for use by small and medium-sized enterprises (SME). These tools invariably incorporate chat systems that facilitate simultaneous input in synchronous electronic meeting environments, allowing what is referred to as “electronic brainstorming.” Although prior research in information systems (IS) has established that electronic brainstorming can be superior to face-to-face brainstorming, there is a lack of detailed guidance regarding how CMC tools should be optimally configured to foster creativity in SMEs. This paper discusses factors to be considered in using CMC tools for creativity brainstorming and proposes recommendations for optimally configuring CMC tools to enhance creativity in SMEs. The recommendations are based on lessons learned from several recent experimental studies on the use of CMC tools for rich brainstorming tasks that require participants to invoke domain-specific knowledge. Based on a consideration of the advantages and disadvantages of the various configuration options, the recommendations provided can form the basis for selecting a CMC tool for creativity brainstorming or for creating an in-house CMC tool for the purpose.

  13. FIRST-based survey of Compact Steep Spectrum sources. II. MERLIN and VLA observations of medium-sized symmetric objects

    NASA Astrophysics Data System (ADS)

    Kunert-Bajraszewska, M.; Marecki, A.; Thomasson, P.; Spencer, R. E.

    2005-09-01

    A new sample of candidate Compact Steep Spectrum (CSS) sources that are much weaker than the CSS source prototypes has been selected from the VLA FIRST catalogue. MERLIN "snapshot" observations of the sources at 5 GHz indicate that six of them have an FR II-like morphology, but are not edge-brightened as is normal for Medium-sized Symmetric Objects (MSOs) and FR IIs. Further observations of these six sources with the VLA at 4.9 GHz and MERLIN at 1.7 GHz, as well as subsequent full-track observations with MERLIN at 5 GHz of what appeared to be the two sources of greatest interest are presented. The results are discussed with reference to the established evolutionary model of CSS sources being young but in which not all of them evolve to become old objects with extended radio structures. A lack of stable fuelling in some of them may result in an early transition to a so-called coasting phase so that they fade away instead of growing to become large-scale objects. It is possible that one of the six sources (1542+323) could be labelled as a prematurely "dying" MSO or a "fader".

  14. The use of bipolar cautery, laparosonic coagulating shears, and vascular clips for hemostasis of small and medium-sized vessels.

    PubMed

    Spivak, H; Richardson, W S; Hunter, J G

    1998-02-01

    Advanced laparoscopic surgery requires a reliable method of hemostasis. In order to determine the efficacy of common hemostatic devices, we tested bipolar electrosurgery (BPES), laparosonic coagulating shears (LCS), and vascular clips (VC) on arteries of various sizes to compare the strength of hemostasis against elevated intraarterial pressure. The procedures were performed on a porcine model through a laparotomy. Segments of visceral arteries were isolated and cannulated with an angiocatheter that was linked to a pressure monitor. After hemostasis with the tested instrument and division of the vessel, the intraarterial pressure was elevated by infusion of saline solution through the angiocatheter. The pressure was recorded when bleeding occurred through the cut end of the vessel or when the pressure reached 300 mm Hg. All three devices were effective in maintaining hemostasis on small (diameter, 0.25-0.5 mm) and medium-sized arteries (diameter, 2-3.5 mm) with a success rate ranging between 75% and 100% (p = n.s.). Practice and technical finesse were required with the use of the LCS and BPES before excellent results could be obtained. The LCS has an advantage over BPES because it allows the surgeon to perform hemostasis and division simultaneously, thus keeping the operating field clean and avoiding instrument adhesion to the tissue.

  15. African swine fever outbreak on a medium-sized farm in Uganda: biosecurity breaches and within-farm virus contamination.

    PubMed

    Chenais, Erika; Sternberg-Lewerin, Susanna; Boqvist, Sofia; Liu, Lihong; LeBlanc, Neil; Aliro, Tonny; Masembe, Charles; Ståhl, Karl

    2017-02-01

    In Uganda, a low-income country in east Africa, African swine fever (ASF) is endemic with yearly outbreaks. In the prevailing smallholder subsistence farming systems, farm biosecurity is largely non-existent. Outbreaks of ASF, particularly in smallholder farms, often go unreported, creating significant epidemiological knowledge gaps. The continuous circulation of ASF in smallholder settings also creates biosecurity challenges for larger farms. In this study, an on-going outbreak of ASF in an endemic area was investigated on farm level, including analyses of on-farm environmental virus contamination. The study was carried out on a medium-sized pig farm with 35 adult pigs and 103 piglets or growers at the onset of the outbreak. Within 3 months, all pigs had died or were slaughtered. The study included interviews with farm representatives as well as biological and environmental sampling. ASF was confirmed by the presence of ASF virus (ASFV) genomic material in biological (blood, serum) and environmental (soil, water, feed, manure) samples by real-time PCR. The ASFV-positive biological samples confirmed the clinical assessment and were consistent with known virus characteristics. Most environmental samples were found to be positive. Assessment of farm biosecurity, interviews, and the results from the biological and environmental samples revealed that breaches and non-compliance with biosecurity protocols most likely led to the introduction and within-farm spread of the virus. The information derived from this study provides valuable insight regarding the implementation of biosecurity measures, particularly in endemic areas.

  16. 75 FR 36012 - Fisheries of the Northeastern United States; 2010 Specifications for the Spiny Dogfish Fishery

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-06-24

    ... United States; 2010 Specifications for the Spiny Dogfish Fishery AGENCY: National Marine Fisheries.... SUMMARY: NMFS announces specifications and management measures for the spiny dogfish fishery for the 2010 fishing year (FY) (May 1, 2010, through April 30, 2011). NMFS is implementing a spiny dogfish quota of...

  17. 77 FR 30224 - Fisheries of the Northeastern United States; Final 2012 Spiny Dogfish Fishery Specifications

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-05-22

    ... Northeastern United States; Final 2012 Spiny Dogfish Fishery Specifications AGENCY: National Marine Fisheries.... SUMMARY: This rule implements a catch limit, commercial quota, and possession limit for the spiny dogfish... Management Councils pursuant to the fishery specification requirements of the Spiny Dogfish...

  18. 77 FR 15991 - Fisheries of the Northeastern United States; Proposed 2012 Spiny Dogfish Fishery Specifications

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-03-19

    ... Northeastern United States; Proposed 2012 Spiny Dogfish Fishery Specifications AGENCY: National Marine... for the spiny dogfish fishery for the 2012 fishing year. The proposed action was developed by the Mid... the Spiny Dogfish Fishery Management Plan. The proposed management measures are supported by the...

  19. 76 FR 32873 - Fisheries of the Northeastern United States; 2011 Specifications for the Spiny Dogfish Fishery

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-06-07

    ... Northeastern United States; 2011 Specifications for the Spiny Dogfish Fishery AGENCY: National Marine Fisheries.... ] SUMMARY: NMFS announces specifications and management measures for the spiny dogfish fishery for the 2011 fishing year (FY) (May 1, 2011, through April 30, 2012). NMFS is implementing a spiny dogfish quota of...

  20. 75 FR 26920 - Mid-Atlantic Fishery Management Council; Spiny Dogfish Amendment 3 Scoping Process

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-05-13

    ...; Spiny Dogfish Amendment 3 Scoping Process AGENCY: National Marine Fisheries Service (NMFS), National... not noted in the initial Notice of Intent (NOI) for Amendment 3 to the Spiny Dogfish Fishery.... The scoping comment period for issues previously announced for Amendment 3 to the Spiny...

  1. 50 CFR 622.453 - Prohibition on harvest of egg-bearing spiny lobster.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 50 Wildlife and Fisheries 12 2013-10-01 2013-10-01 false Prohibition on harvest of egg-bearing... Prohibition on harvest of egg-bearing spiny lobster. (a) Egg-bearing spiny lobster in the Caribbean EEZ must be returned to the water unharmed. An egg-bearing spiny lobster may be retained in a trap,...

  2. 50 CFR 622.453 - Prohibition on harvest of egg-bearing spiny lobster.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 50 Wildlife and Fisheries 12 2014-10-01 2014-10-01 false Prohibition on harvest of egg-bearing... Prohibition on harvest of egg-bearing spiny lobster. (a) Egg-bearing spiny lobster in the Caribbean EEZ must be returned to the water unharmed. An egg-bearing spiny lobster may be retained in a trap,...

  3. 50 CFR 648.230 - Spiny dogfish Annual Catch Limits (ACLs).

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 50 Wildlife and Fisheries 12 2012-10-01 2012-10-01 false Spiny dogfish Annual Catch Limits (ACLs... Management Measures for the Spiny Dogfish Fishery § 648.230 Spiny dogfish Annual Catch Limits (ACLs). (a) The... make recommendations to the Councils for changes in measures intended to ensure ACLs are not...

  4. 50 CFR 648.230 - Spiny dogfish Annual Catch Limits (ACLs).

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 50 Wildlife and Fisheries 12 2013-10-01 2013-10-01 false Spiny dogfish Annual Catch Limits (ACLs... Management Measures for the Spiny Dogfish Fishery § 648.230 Spiny dogfish Annual Catch Limits (ACLs). (a) The... make recommendations to the Councils for changes in measures intended to ensure ACLs are not...

  5. 50 CFR 648.230 - Spiny dogfish Annual Catch Limits (ACLs).

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 50 Wildlife and Fisheries 12 2014-10-01 2014-10-01 false Spiny dogfish Annual Catch Limits (ACLs... Management Measures for the Spiny Dogfish Fishery § 648.230 Spiny dogfish Annual Catch Limits (ACLs). (a) The... make recommendations to the Councils for changes in measures intended to ensure ACLs are not...

  6. Inferred Variable FeO Content in Medium-sized Lunar Pyroclastic Deposits from LRO Diviner Data

    NASA Technical Reports Server (NTRS)

    Bennett, K. A.; Horgan, B.; Greenhagen, B.; Allen, C.; Bell, J. F., III

    2014-01-01

    Lunar pyroclastic deposits (LPDs) are low albedo features that mantle underlying terrain (Gaddis et al. 1985). They are high priority targets for science and exploration as they are believed to originate from and therefore reflect the composition of the deep lunar interior (NRC, 2011). They are also the best potential resource of oxygen out of any Apollo samples (Allen et al. 1996). Historically, LPDs have been divided into regional versus local categories (Gaddis et al. 2003). The large (>1000 km2 area) regional deposits are deeply sourced (>400 km deep) and result from fire fountaining. Small (<1000 km2) local deposits are thought to result from Vulcanian eruptions in which magma is slowly emplaced beneath the surface until enough volatiles exsolve and the high pressure causes an explosion. Bennett et al. (2013) identified a local deposit (674 km2 area) that may have resulted from both Vulcanian activity and fire fountaining. This deposit potentially represents a new intermediate class of LPDs that straddles the interface between the two formation mechanisms. The deposit also exhibits the highest inferred FeO wt.% of any known lunar glass. In this work we investigate the inferred FeO abundances of other medium-sized deposits to characterize this potential new class of deposits and understand the magnitude of variations in inferred FeO among pyroclastic deposits. We use the method of Greenhagen et al. (2010) to calculate the wavelength of the Christiansen Feature (CF) from Lunar Reconnaissance Orbiter Diviner Lunar Radiometer instrument thermal-infrared observations for four medium-sized deposits. From the CF values, we estimate each deposit's FeO abundance using the method of Allen et al. (2012). The four LPDs that we examined (Oppenheimer South, Beer, Cleomedes, and J. Herschel) all have average CF values from 8.22-8.28 microns, corresponding to FeO abundances of approx. 10-15 wt.%. All of these values are within the range and uncertainties of FeO abundances

  7. Examinations on the Meteorologic Factors of Urban Heat Island Development in Small and Medium-sized Towns of Hungary

    NASA Astrophysics Data System (ADS)

    Szegedi, S.; Gyarmati, R.; Kapocska, L.; Toth, T.

    2010-09-01

    EXAMINATIONS ON THE METEOROLOGICAL FACTORS OF URBAN HEAT ISLAND DEVELOPMENT IN SMALL AND MEDIUM-SIZED TOWNS OF HUNGARY Sandor Szegedi, Renata Gyarmati, Laszlo Kapocska and Tamas Toth University of Debrecen Department of Meteorology, 4032 Debrecen Egyetem tér 1. The thermal difference between the settlements and their environment is called urban heat island (UHI). Potential UHI intensities are mainly determined by the size, population and built-up structure of settlements. Meteorological conditions have a determinant impact on the development of the heat island at a certain moment. International and Hungarian studies usually deal with metropolises and big cities; much less attention is paid to medium-sized and small towns. Consequently this study has been focused on the development of UHI in such Hungarian urbanized areas as mentioned above. Settlements, located near the city of Debrecen (ca. 220,000 inhabitants) in East Hungary, with population of about 30000, 20000 10000 and 1000 were chosen for the research. Car-mounted digital thermometers with data loggers were used. Twenty four measurements were carried out during a one-year-long campaign in 2003-2004. Synoptic conditions, especially cloudiness, wind direction and wind speed were taken to consideration as determinant factors. Spatial characteristics of UHI have been described. Results have proved the existence of UHI even in the smallest settlement under suitable weather conditions. The non-heating season proved to be more advantageous for the development of UHI due to stronger irradiance and frequent anticyclonic synoptic conditions. Effects of cloudiness and wind speed have been revealed as well. St type clouds have proved to be most effective in preventing the formation of UHI. A 90-100% St cover could completely eliminate the thermal differences between natural and artificial surfaces. Ci type clouds had the weakest impact, they could prevent the formation of the heat island only in the smallest

  8. A passive DOAS instrument for trace gas measurements on medium sized UAS: Instrumental design and first measurements.

    NASA Astrophysics Data System (ADS)

    Horbanski, Martin; Pöhler, Denis; Mahr, Tobias; Wagner, Thomas; Keleshis, Christos; Ioannou, Stelios; Lange, Manfred A.; Lelieveld, Jos; Platt, Ulrich

    2013-04-01

    Unmanned Aerial Systems (UAS) are a new powerful tool for observations in the atmospheric boundary layer. Recent developments in measuring technology allow the construction of compact and sensitive active and passive DOAS instruments which can fit the space and weight constraints on UAS. This opens new possibilities for trace gas measurements in the lower troposphere, especially in areas which are not accessible to manned aviation e.g. volcanic plumes or which should be monitored regularly (e.g. industrial emissions of a stack). We present a new developed passive DOAS instrument for the APAESO Platform of the Cyprus Institute, a medium size UAS. It is equipped with two telescopes for observations in downward (nadir) and horizontal (limb) viewing direction, respectively. Thus it allows determining height profiles and the horizontal distribution of trace gases. This is accomplished by analyzing the radiation collected by the telescopes with compact spectrometers, which cover the UV-blue spectral range allowing to measure a broad variety of atmospheric trace gases (e.g. NO2, SO2, BrO, IO, H2O ...) as well as aerosol properties via O4 absorption. Additionally, the nadir direction is equipped with a VIS-NIR spectrometer. It is used to measure reflection spectra of different types of vegetation. These will serve as references for satellite measurements to create global maps. First measurements on the APAESO platform were performed in October 2012 on Cyprus in a rural area south of Nicosia. The instrument is shown to work reliably and was able to detect NO2, H2O and O4 at atmospheric column densities. The instrumental design and first measurements will be presented and discussed.

  9. Concentration, sources and light absorption characteristics of dissolved organic carbon on a medium-sized valley glacier, northern Tibetan Plateau

    NASA Astrophysics Data System (ADS)

    Yan, Fangping; Kang, Shichang; Li, Chaoliu; Zhang, Yulan; Qin, Xiang; Li, Yang; Zhang, Xiaopeng; Hu, Zhaofu; Chen, Pengfei; Li, Xiaofei; Qu, Bin; Sillanpää, Mika

    2016-11-01

    Light-absorbing dissolved organic carbon (DOC) constitutes a major part of the organic carbon in glacierized regions, and has important influences on the carbon cycle and radiative forcing of glaciers. However, few DOC data are currently available from the glacierized regions of the Tibetan Plateau (TP). In this study, DOC characteristics of a medium-sized valley glacier (Laohugou Glacier No. 12, LHG) on the northern TP were investigated. Generally, DOC concentrations on LHG were comparable to those in other regions around the world. DOC concentrations in snow pits, surface snow and surface ice (superimposed ice) were 332 ± 132, 229 ± 104 and 426 ± 270 µg L-1, respectively. The average discharge-weighted DOC of proglacial stream water was 238 ± 96 µg L-1, and the annual DOC flux released from this glacier was estimated to be 6949 kg C yr-1, of which 46.2 % of DOC was bioavailable and could be decomposed into CO2 within 1 month of its release. The mass absorption cross section (MAC) of DOC at 365 nm was 1.4 ± 0.4 m2 g-1 in snow and 1.3 ± 0.7 m2 g-1 in ice, similar to the values for dust transported from adjacent deserts. Moreover, there was a significant relationship between DOC and Ca2+; therefore, mineral dust transported from adjacent arid regions likely made important contributions to DOC of the glacierized regions, although contributions from autochthonous carbon and autochthonous/heterotrophic microbial activity cannot be ruled out. The radiative forcing of snow pit DOC was calculated to be 0.43 W m-2, demonstrating that DOC in snow needs to be taken into consideration in accelerating melt of glaciers on the TP.

  10. Contamination and risk assessment of metals in road-deposited sediments in a medium-sized city of China.

    PubMed

    Bian, Bo; Lin, Cheng; Wu, Hai suo

    2015-02-01

    Road-deposited sediment (RDS) is a valuable environmental medium for characterizing contamination of metals in urban areas and the associated risks to human health. A total of 62 RDS samples were collected for metal test in four urban areas in a medium size city in eastern China. The areas that represented different land uses consisted of intense traffic area (ITA), commercial area (CA), residential area (RA), and riverside park area (RPA). The effects of particle size and different land uses on metal contamination and health risk were the major focus in this study. The test results showed that RDS in ITA appeared to have higher metal content, enrichment factor (EF), ecological risk index (RI), and the non-cancer and cancer risks than in the other areas. The metal contamination and health risk increased inversely with particle size. The particles less than 63 μm were found to be most critical in development of metal contamination and health risk. The EF was measured to be greater than 2.0 in the four areas, indicating a moderate enrichment. The measured RI ranged between 50 and 200, indicating considerable to moderate risks. The non-cancer risk for children was high in the four areas but was low for adults in all test areas except in ITA. The cancer risk of Cr for children was high in all test areas. Based on the test results, the contamination control and management for metals in RDS shall focus on the effects from such factors as particles (<63 μm) and the land use for intense traffic (ITA).

  11. Synthesis of enantiomerically pure, highly functionalized, medium-sized carbocycles from carbohydrates: formal total synthesis of (+)-calystegine b(2).

    PubMed

    Marco-Contelles, José; de Opazo, Elsa

    2002-05-31

    The free radical cyclization (FR) and the ring-closing metathesis (RCM) reaction have been analyzed in order to develop new and original synthetic protocols for the synthesis of enantiomerically pure, highly functionalized, medium-sized carbocycles from carbohydrates. As a result, we report here for the first time examples of the 7-exo FR cyclization of acyclic radical precursors derived from sugars. This process appears to be extremely sensitive to the conformational mobility of the radical species in the transition state. The use of two isopropylidene groups blocking four of the total present hydroxyl groups and a good radical acceptor (as an alpha,beta-unsaturated ester) are mandatory conditions for a successful ring closure protocol. The RCM reaction by using Grubbs' catalyst on selected carbohydrate-derived precursors has afforded variable yields of the expected unsaturated cycloheptane or cycloctane derivatives. The synthesis of the cycloheptitols has been carried out in good yields, regardless of the absolute configuration at the different stereocenters and the nature of the O-functional groups bound in allylic positions to one of the double bonds implicated in the metathesis reaction. Conversely, in the cyclooctane synthesis, we have observed that the success of the reaction depends not only on the absolute configuration at the different stereocenters close to the double bonds but also on the nature of the O-protecting groups on these stereocenters. Finally, the RCM strategy has been used in an attempt to prepare natural (+)-calystegine B(2) from D-glucose. The synthesis of compound 92 from D-glucose constitutes a formal total synthesis of (+)-calystegine B(2), showing the importance of the steric hindrance in allylic positions for a successful RCM reaction.

  12. The Soviet Union and Eastern Europe: A Bibliographic Guide to Recommended Books for Small and Medium-Sized Libraries and School Media Centers.

    ERIC Educational Resources Information Center

    Horak, Stephan M.

    Intended to aid librarians in small- and medium-sized libraries and media centers, this annotated bibliography lists 1,555 books focusing on the Soviet Union and Eastern Europe. The book is divided into four parts: (1) "General and Interrelated Themes--Union of the Soviet Socialist Republics and Eastern European Countries"; (2)…

  13. Impact of Top Management Team on Firm Performance in Small and Medium-Sized Enterprises Adopting Commercial Open-Source Enterprise Resource Planning

    ERIC Educational Resources Information Center

    Cereola, Sandra J.; Wier, Benson; Norman, Carolyn Strand

    2012-01-01

    Based on the large number of small and medium-sized enterprises (SMEs) in the United States, their increasing interest in enterprise-wide software systems and their impact on the US economy, it is important to understand the determinants that can facilitate the successful implementation and assimilation of such technology into these firms' daily…

  14. Towards a Service-Oriented Enterprise: The Design of a Cloud Business Integration Platform in a Medium-Sized Manufacturing Enterprise

    ERIC Educational Resources Information Center

    Stamas, Paul J.

    2013-01-01

    This case study research followed the two-year transition of a medium-sized manufacturing firm towards a service-oriented enterprise. A service-oriented enterprise is an emerging architecture of the firm that leverages the paradigm of services computing to integrate the capabilities of the firm with the complementary competencies of business…

  15. Knowledge Management as a Service: Co-operation between Small and Medium-Sized Enterprises (SMEs) and Training, Consulting and Research Institutions.

    ERIC Educational Resources Information Center

    Scheff, Josef; Kailer, Norbert

    1999-01-01

    A study of 372 companies examined the cooperation between small-to-medium-sized businesses and external providers of training in Austria. New forms of cooperation such as integrated training and consulting programs, process consultation of in-house projects, and support of cooperation are needed. (JOW)

  16. Funding Continuing Training in Small and Medium-Sized Enterprises: Discussion and Case Studies from across the EU. CEDEFOP Panorama Series.

    ERIC Educational Resources Information Center

    Pukkinen, Tommi; Romijn, Clemens; Elson-Rogers, Sarah

    There are three main parts to this report of a study that used case studies to showcase the different approaches used to encourage more continuing training within small and medium-sized enterprises (SMEs) across the European Union (EU). Section 1 discusses the importance of funding training in SMEs and highlights the various types of funding…

  17. A Cost-Benefit Analysis of a Collections Inventory Project: A Statistical Analysis of Inventory Data from a Medium-Sized Academic Library

    ERIC Educational Resources Information Center

    Sung, Jan S.; Whisler, John A.; Sung, Nackil

    2009-01-01

    Using an electronic shelf-reading system a cost-benefit analysis was conducted of an inventory/shelf-reading project in a medium-sized academic library. Analyses include time spent, cataloging discrepancies, books found with active statuses, mis-shelving rate and distance, and subsequent use of found books. Correctly re-shelving "missing"…

  18. Energy efficiency in the US economy technical report four: Analysis of energy-efficiency investment decisions by small and medium-sized manufacturers

    SciTech Connect

    1996-03-01

    This report highlights the results of a comprehensive analysis of investment decisions regarding energy-efficiency measures at small and medium-sized manufacturing plants. The analysis is based primarily on the experiences of companies participating in the US Department of Energy`s Industrial Assessment Center (IAC) program.

  19. Paternal behavior in the spiny mouse (Acomys cahirinus).

    PubMed

    Makin, J W; Porter, R H

    1984-07-01

    The responsiveness of adult male spiny mice (Acomys cahirinus) to both their own and alien precocial young was investigated. Paternal behavior was manifested primarily by the males huddling with their offspring and the coordination of pup attendance between adult males and females. With less than 2 days exposure to their own neonates, males were found to discriminate between their own and alien young. Experience plays an important role in the development of paternal behavior in spiny mice. Males who have never had pups of their own sniff and attack unfamiliar neonates more than males who have fathered pups. The adaptive significance of paternal investment in this uniquely precocial murid rodent was discussed.

  20. Circadian activity rhythms in the spiny mouse, Acomys cahirinus.

    PubMed

    Weber, E T; Hohn, V M

    2005-11-15

    Circadian locomotor rhythms were examined in adult common spiny mice, Acomys cahirinus. Spiny mice demonstrated nocturnal activity, with onset of activity coinciding promptly with onset of darkness. Re-entrainment to 6-h delays of the light-dark cycle was accomplished faster than to 6-h advances. Access to running wheels yielded significant changes in period and duration of daily activity. Novelty-induced wheel running had no effect on phase of activity rhythms. Circadian responses to light at various times of the circadian cycle were temporally similar to those observed in other nocturnal rodent species. No gender differences were observed in any of the parameters measured.

  1. 50 CFR 648.231 - Spiny dogfish Annual Catch Target (ACT) and Total Allowable Level of Landings (TAL).

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 50 Wildlife and Fisheries 12 2012-10-01 2012-10-01 false Spiny dogfish Annual Catch Target (ACT... OF THE NORTHEASTERN UNITED STATES Management Measures for the Spiny Dogfish Fishery § 648.231 Spiny dogfish Annual Catch Target (ACT) and Total Allowable Level of Landings (TAL). (a) The Spiny...

  2. 78 FR 25862 - Fisheries of the Northeastern United States; Final 2013-2015 Spiny Dogfish Fishery Specifications

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-05-03

    ... United States; Final 2013-2015 Spiny Dogfish Fishery Specifications AGENCY: National Marine Fisheries.... SUMMARY: This rule implements specifications and management measures for the spiny dogfish fishery for the... spiny dogfish fishery while maintaining the conservation objectives of the Spiny Dogfish...

  3. 50 CFR 648.231 - Spiny dogfish Annual Catch Target (ACT) and Total Allowable Level of Landings (TAL).

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 50 Wildlife and Fisheries 12 2014-10-01 2014-10-01 false Spiny dogfish Annual Catch Target (ACT... OF THE NORTHEASTERN UNITED STATES Management Measures for the Spiny Dogfish Fishery § 648.231 Spiny dogfish Annual Catch Target (ACT) and Total Allowable Level of Landings (TAL). (a) The Spiny...

  4. 50 CFR 648.231 - Spiny dogfish Annual Catch Target (ACT) and Total Allowable Level of Landings (TAL).

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 50 Wildlife and Fisheries 12 2013-10-01 2013-10-01 false Spiny dogfish Annual Catch Target (ACT... OF THE NORTHEASTERN UNITED STATES Management Measures for the Spiny Dogfish Fishery § 648.231 Spiny dogfish Annual Catch Target (ACT) and Total Allowable Level of Landings (TAL). (a) The Spiny...

  5. Evaluation of the COSHH Essentials model with a mixture of organic chemicals at a medium-sized paint producer.

    PubMed

    Lee, Eun Gyung; Slaven, James; Bowen, Russell B; Harper, Martin

    2011-01-01

    The Control of Substances Hazardous to Health (COSHH) Essentials model was evaluated using full-shift exposure measurements of five chemical components in a mixture [acetone, ethylbenzene, methyl ethyl ketone, toluene, and xylenes] at a medium-sized plant producing paint materials. Two tasks, batch-making and bucket-washing, were examined. Varying levels of control were already established in both tasks and the average exposures of individual chemicals were considerably lower than the regulatory and advisory 8-h standards. The average exposure fractions using the additive mixture formula were also less than unity (batch-making: 0.25, bucket-washing: 0.56) indicating the mixture of chemicals did not exceed the combined occupational exposure limit (OEL). The paper version of the COSHH Essentials model was used to calculate a predicted exposure range (PER) for each chemical according to different levels of control. The estimated PERs of the tested chemicals for both tasks did not show consistent agreement with exposure measurements when the comparison was made for each control method and this is believed to be because of the considerably different volatilities of the chemicals. Given the combination of health hazard and exposure potential components, the COSHH Essentials model recommended a control approach 'special advice' for both tasks, based on the potential reproductive hazard ascribed to toluene. This would not have been the same conclusion if some other chemical had been substituted (for example styrene, which has the same threshold limit value as toluene). Nevertheless, it was special advice, which had led to the combination of hygienic procedures in place at this plant. The probability of the combined exposure fractions exceeding unity was 0.0002 for the batch-making task indicating that the employees performing this task were most likely well protected below the OELs. Although the employees involved in the bucket-washing task had greater potential to exceed

  6. Use of High Spatial Resolution Remote Sensing for Hydro-Geomorphologic Analysis of Medium-sized Arid Basins

    NASA Astrophysics Data System (ADS)

    Sadeh, Yuval; Blumberg, Dan G.; Cohen, Hai; Morin, Efrat; Maman, Shimrit

    2016-04-01

    Arid environments are often remote, expansive, difficult to access and especially vulnerable to flash flood hazards due to the poor understanding of the phenomenon and the lack of meteorological, geomorphological, and hydrological data. For many years, catchment characteristics have been observed using point-based measurements such as rain gauges and soil sample analysis; on the other hand, use of remote sensing technologies can provide spatially continuous hydrological parameters and variables. The advances in remote sensing technologies can provide new geo-spatial data using high spatial and temporal resolution for basin-scale geomorphological analysis and hydrological models. This study used high spatial resolution remote sensing for hydro-geomorphologic analysis of the arid medium size Rahaf watershed (76 km2), located in the Judean Desert, Israel. During the research a high resolution geomorphological map of Rahaf basin was created using WorldView-2 multispectral satellite imageries; surface roughness was estimated using SIR-C and COSMO-SkyMed Synthetic Aperture Radar (SAR) spaceborne sensors; and rainstorm characteristics were extracted using ground-based meteorological radar. The geomorphological mapping of Rahaf into 17 classes with good accuracy. The surface roughness extraction using SAR over the basin showed that the correlation between the COSMO-SkyMed backscatter coefficient and the surface roughness was very strong with an R2 of 0.97. This study showed that using x-band spaceborne sensors with high spatial resolution, such as COSMO-SkyMed, are more suitable for surface roughness evaluation in flat arid environments and should be in favor with longer wavelength operating sensors such as the SIR-C. The current study presents an innovative method to evaluate Manning's hydraulic roughness coefficient (n) in arid environments using radar backscattering. The weather radar rainfall data was calibrated using rain gauges located in the watershed. The

  7. Think Locally, Act Locally: The Detection of Small, Medium-Sized, and Large Communities in Large Networks

    PubMed Central

    Jeub, Lucas G. S.; Balachandran, Prakash; Porter, Mason A.; Mucha, Peter J.; Mahoney, Michael W.

    2016-01-01

    It is common in the study of networks to investigate intermediate-sized (or “meso-scale”) features to try to gain an understanding of network structure and function. For example, numerous algorithms have been developed to try to identify “communities,” which are typically construed as sets of nodes with denser connections internally than with the remainder of a network. In this paper, we adopt a complementary perspective that “communities” are associated with bottlenecks of locally-biased dynamical processes that begin at seed sets of nodes, and we employ several different community-identification procedures (using diffusion-based and geodesic-based dynamics) to investigate community quality as a function of community size. Using several empirical and synthetic networks, we identify several distinct scenarios for “size-resolved community structure” that can arise in real (and realistic) networks: (i) the best small groups of nodes can be better than the best large groups (for a given formulation of the idea of a good community); (ii) the best small groups can have a quality that is comparable to the best medium-sized and large groups; and (iii) the best small groups of nodes can be worse than the best large groups. As we discuss in detail, which of these three cases holds for a given network can make an enormous difference when investigating and making claims about network community structure, and it is important to take this into account to obtain reliable downstream conclusions. Depending on which scenario holds, one may or may not be able to successfully identify “good” communities in a given network (and good communities might not even exist for a given community quality measure), the manner in which different small communities fit together to form meso-scale network structures can be very different, and processes such as viral propagation and information diffusion can exhibit very different dynamics. In addition, our results suggest that

  8. Development of a Low NOx Medium sized Industrial Gas Turbine Operating on Hydrogen-Rich Renewable and Opportunity Fuels

    SciTech Connect

    Srinivasan, Ram

    2013-07-31

    This report presents the accomplishments at the completion of the DOE sponsored project (Contract # DE-FC26-09NT05873) undertaken by Solar Turbines Incorporated. The objective of this 54-month project was to develop a low NOx combustion system for a medium sized industrial gas turbine engine operating on Hydrogen-rich renewable and opportunity Fuels. The work in this project was focused on development of a combustion system sized for 15MW Titan 130 gas turbine engine based on design analysis and rig test results. Although detailed engine evaluation of the complete system is required prior to commercial application, those tasks were beyond the scope of this DOE sponsored project. The project tasks were organized in three stages, Stages 2 through 4. In Stage 2 of this project, Solar Turbines Incorporated characterized the low emission capability of current Titan 130 SoLoNOx fuel injector while operating on a matrix of fuel blends with varying Hydrogen concentration. The mapping in this phase was performed on a fuel injector designed for natural gas operation. Favorable test results were obtained in this phase on emissions and operability. However, the resulting fuel supply pressure needed to operate the engine with the lower Wobbe Index opportunity fuels would require additional gas compression, resulting in parasitic load and reduced thermal efficiency. In Stage 3, Solar characterized the pressure loss in the fuel injector and developed modifications to the fuel injection system through detailed network analysis. In this modification, only the fuel delivery flowpath was modified and the air-side of the injector and the premixing passages were not altered. The modified injector was fabricated and tested and verified to produce similar operability and emissions as the Stage 2 results. In parallel, Solar also fabricated a dual fuel capable injector with the same air-side flowpath to improve commercialization potential. This injector was also test verified to produce 15

  9. A superovulation protocol for the spiny mouse (Acomys cahirinus).

    PubMed

    Pasco, Rachael; Gardner, David K; Walker, David W; Dickinson, Hayley

    2012-01-01

    This study aimed to develop a superovulation protocol for the spiny mouse (Acomys cahirinus). The spiny mouse is a desert-adapted rodent species, with a long oestrus cycle (11 days) compared with rat and mouse, and gives birth to few (mean litter size is 3) precocial offspring after a relatively long gestation (39 days). We successfully optimised a superovulation protocol that elicited a 5-fold increase in the normal ovulation rate of this species. To induce superovulation in the spiny mouse 2 injections of equine chorionic gonadotrophin (eCG, 10 IU each), 9h apart, were required, followed by 20 IU of human chorionic gonadotrophin (hCG). This protocol was successful in 100% of females trialed and at 33 h post-hCG an average of 14.7 ± 1.5, 1-2 cell embryos were recovered. Histological analysis of ovaries following superovulation revealed large corpus lutea and post-ovulatory follicles occupying a large part of the ovary. Ovulation commenced 6-12 h after the hCG injection and continued until 24-33 h post-hCG as indicated by both histological analysis of ovaries and the presence of oocytes/embryos in the oviduct. This superovulation protocol will facilitate the development of an in vitro culture system for spiny mouse embryos.

  10. Co-localization of the D1 dopamine receptor in a subset of DARPP-32-containing neurons in rat caudate-putamen.

    PubMed

    Langley, K C; Bergson, C; Greengard, P; Ouimet, C C

    1997-06-01

    DARPP-32 (dopamine- and cyclic AMP-regulated phosphoprotein, apparent molecular weight of 32,000) is part of the D1 dopamine receptor signal transduction cascade. Both the D1 receptor and DARPP-32 are found in the caudate putamen, but it is not known if they co-localize in the medium-sized spiny neurons. In the present study, double-labelling immunocytochemistry was used to simultaneously localize the D1 receptor and DARPP-32 in the rat caudate-putamen. The neuropil was heavily and uniformly immunoreactive for both the D1 receptor and DARPP-32. All cell bodies immunopositive for the D1 receptor were immunopositive for DARPP-32. The D1 receptor was not detectable, however, in nearly half of the DARPP-32-containing cell bodies. DARPP-32 is present in striatopallidal and striatonigral projections. The D1 receptor co-localized with DARPP-32 in fibres of the entopeduncular nucleus and the pars reticulata of the substantia nigra. In the globus pallidus, however, D1 receptor immunoreactivity was barely detectable, while DARPP-32 immunolabelling of axons and axon terminals was intense. These data suggest that the striatal somata containing both the D1 receptor and DARPP-32 project to the entopeduncular nucleus and substantia nigra, whereas somata containing only DARPP-32 immunoreactivity project to the globus pallidus. Thus, the differences in expression of the D1 receptor and of DARPP-32 within striatal cell bodies are likely reflected in their projections. The co-localization of the D1 receptor and DARPP-32 is consistent with the known regulation of DARPP-32 phosphorylation by D1 receptor activation. The demonstration of a large population of striatal neurons that contain DARPP-32 but apparently do not contain D1 receptors substantiates the premise that these cells have an alternative signal transduction pathway. Subsequent studies are needed to search for a signal transduction pathway for these neurons analogous to the dopamine D1 receptor pathway.

  11. Morphology of VIP/nNOS-immunoreactive myenteric neurons in the human gut.

    PubMed

    Brehmer, A; Schrödl, F; Neuhuber, W

    2006-05-01

    In this study, we characterized human myenteric neurons co-immunoreactive for neuronal nitric oxide synthase (nNOS) and vasoactive intestinal peptide (VIP) by their morphology and their proportion as related to the putative entire myenteric neuronal population. Nine wholemounts (small and large intestinal samples) from nine patients were triple-stained for VIP, neurofilaments (NF) and nNOS. Most neurons immunoreactive for all three markers displayed radially emanating, partly branching dendrites with spiny endings. These neurons were called spiny neurons. The spiny character of their dendrites was more pronounced in the small intestinal specimens and differed markedly from enkephalinergic stubby neurons described earlier. Exclusively in the duodenum, some neurons displayed prominent main dendrites with spiny side branches. Of the axons which could be followed from the ganglion of origin within primary strands of the myenteric plexus beyond the next ganglion (70 out of 140 traced neurons), 94.3% run anally and 5.7% orally. Very few neurons reactive for both VIP and nNOS could not be morphologically classified due to weak or absent NF-immunoreactivity. Another six wholemounts were triple-stained for VIP, nNOS and Hu proteins (HU). The proportion of VIP/nNOS-coreactive neurons in relation to the number of HU-reactive neurons was between 5.8 and 11.5% in the small and between 10.6 and 17.5% in the large intestinal specimens. We conclude that human myenteric spiny neurons co-immunoreactive for VIP and nNOS represent either inhibitory motor or descending interneurons.

  12. Axial levodopa-induced dyskinesias and neuronal activity in the dorsal striatum.

    PubMed

    Alberico, Stephanie L; Kim, Young-Cho; Lence, Tomas; Narayanan, Nandakumar S

    2017-02-20

    Levodopa-induced dyskinesias are abnormal involuntary movements that limit the effectiveness of treatments for Parkinson's disease. Although dyskinesias involve the striatum, it is unclear how striatal neurons are involved in dyskinetic movements. Here we record from striatal neurons in mice during levodopa-induced axial dyskinesias. We developed an automated 3-dimensional motion tracking system to capture the development of axial dyskinesias at ∼10ms resolution, and correlated these movements with neuronal activity of striatal medium spiny neurons and fast-spiking interneurons. The average firing rate of medium spiny neurons increased as axial dyskinesias developed, and both medium spiny neurons and fast-spiking interneurons were modulated around axial dyskinesias. We also found that delta field potential power increased in the striatum with dyskinesia, and that this increased delta power coupled with striatal neurons. Our findings provide insight into how striatal networks change as levodopa-induced dyskinesias develop, and suggest that increased medium spiny neuron firing, increased delta field potential power, and abnormal delta-coupling may be neurophysiological signatures of dyskinesias. These data could be helpful in understanding the role of the striatum in the pathogenesis of dyskinesias in Parkinson's disease.

  13. Relative impact of on-road vehicular and point-source industrial emissions of air pollutants in a medium-sized Andean city

    NASA Astrophysics Data System (ADS)

    González, C. M.; Gómez, C. D.; Rojas, N. Y.; Acevedo, H.; Aristizábal, B. H.

    2017-03-01

    Cities in emerging countries are facing a fast growth and urbanization; however, the study of air pollutant emissions and its dynamics is scarce, making their populations vulnerable to potential effects of air pollution. This situation is critical in medium-sized urban areas built along the tropical Andean mountains. This work assesses the contribution of on-road vehicular and point-source industrial activities in the medium-sized Andean city of Manizales, Colombia. Annual fluxes of criteria pollutants, NMVOC, and greenhouse gases were estimated. Emissions were dominated by vehicular activity, with more than 90% of total estimated releases for the majority of air pollutants. On-road vehicular emissions for CO (43.4 Gg/yr) and NMVOC (9.6 Gg/yr) were mainly associated with the use of motorcycles (50% and 81% of total CO and NMVOC emissions respectively). Public transit buses were the main source of PM10 (47%) and NOx (48%). The per-capita emission index was significantly higher in Manizales than in other medium-sized cities, especially for NMVOC, CO, NOx and CO2. The unique mountainous terrain of Andean cities suggest that a methodology based on VSP model could give more realistic emission estimates, with additional model components that include slope and acceleration. Food and beverage facilities were the main contributors of point-source industrial emissions for PM10 (63%), SOx (55%) and NOx (45%), whereas scrap metal recycling had high emissions of CO (73%) and NMVOC (47%). Results provide the baseline for ongoing research in atmospheric modeling and urban air quality, in order to improve the understanding of air pollutant fluxes, transport and transformation in the atmosphere. In addition, this emission inventory could be used as a tool to identify areas of public health exposure and provide information for future decision makers.

  14. Eruptive activity of enigmatic medium-sized volcanoes in the Michoacán-Guanajuato Volcanic Field (MGVF), Central Mexico: The case of El Metate

    NASA Astrophysics Data System (ADS)

    Chevrel, M.; Siebe, C.; Guilbaud, M. N.

    2014-12-01

    The MGVF has a total area of ca. 40,000 km2 and is well known for being the host of the only two monogenetic volcanoes in Mexico that were born in historical times: Jorullo (1759-1774) and Paricutin (1943-1952). Another particularity of the MGVF is its high number of eruptive vents with over 1000 small monogenetic cones and associated lava flows (average vol. of 0.021 km3) and ca. 400 medium-sized volcanoes (average vol. from 0.5 to 50 km3). Most of these medium-sized volcanoes may be characterized as shields that were produced dominantly by effusive activity as opposed to the small cones formed also by explosive phases of activity. The products of the small cones range from olivine basalts to andesites whereas the medium-sized volcanoes are restricted to a smaller compositional range in the andesitic domain. Although the medium-sized volcanoes are more sparsely distributed in time and space and less abundant than the small cones, the risks associated with renewal of this type of activity should not be neglected. This study focuses on El Metate which is probably the youngest shield of the MGVF (< 3,700 y. BP). Unlike a typical shield volcano composed of a succession of thin fluid basaltic flows, El Metate consists of well-preserved >60 m thick andesite flows distributed radially around a summit dome. Detailed mapping and sampling allowed us to reconstruct its eruptive activity and the time sequence of lava flow emplacement. We have identified 13 individual lava flows with lengths ranging between 3 and 15 km covering 103 km2 and average thicknesses between 60 and 150 m. Individual volumes range between 0.5 and 3.5 km3 for a total of 11 to 15 km3. Estimates of flow emplacement parameters indicate maximum average effusion rates ranging between 15 and 100 m3.s-1 and a cumulative duration from 15 to 30 years. Such a short emplacement time is comparable to the historical monogenetic eruption of nearby Paricutin volcano (9 years) but the erupted volume of lava is

  15. What affects the innovation performance of small and medium-sized enterprises (SMEs) in the biotechnology industry? An empirical study on Korean biotech SMEs.

    PubMed

    Kang, Kyung-Nam; Lee, Yoon-Sik

    2008-10-01

    Research-intensive small and medium-sized enterprises (SMEs) play a crucial role in the advancement of the biotechnology industry. This paper explored the impacts of internal and contextual variables on innovative activity in Korea and compared the results of this analysis with previous studies of other countries. Our analysis of 149 Korean biotech SMEs showed that the ratio of R&D expenditure to sales, the ratio of R&D employees to total employees, CEO characteristics, governmental support and international networking are positively correlated with a firm's innovation performance. The results may help decision makers to better foster SMEs in the Korean biotechnology industry.

  16. Post-operative complications associated with the Arthrex Canine Cranial Cruciate Ligament Repair Anchor System in small- to medium-sized dogs: A retrospective analysis (2009–2012)

    PubMed Central

    Rappa, Nick S.; Radasch, Robert M.

    2016-01-01

    This study classified and determined the post-operative complication rate associated with stabilization of cranial (CCL) ligament deficient stifles in small- to medium-sized dogs with the Arthrex Canine Cranial Cruciate Ligament Repair Anchor System (CCLRAS). Eighty-five medical records from 2009 to 2012 from 1 institution were evaluated. Complications were classified according to previously proposed definitions for orthopedic studies in veterinary medicine. Fifty-two owners were contacted by telephone at least 6 months after surgery and given a questionnaire to classify complications related to the implant. A visual analog scale was used to assess functionality and degree of pain. The overall complication rate was 30.3% with an inflammation-infection rate of 5.4% and a documented infection rate requiring implant removal of 1.8%. Owners reported full or acceptable function in 96% of cases with an average functional score of 86.5. Stabilization of CCL-deficient stifles in small- to medium-sized dogs with the Arthrex Canine CCLRAS is reliable with acceptable complication rates. PMID:27493284

  17. Chemical management and control strategies: experiences from the GTZ pilot project on chemical safety in Indonesian small and medium-sized enterprises.

    PubMed

    Tischer, M; Scholaen, S

    2003-10-01

    In 1998 the Deutsche Gesellschaft für Technische Zusammenarbeit (GTZ) launched the Convention Project on Chemical Safety in developing countries. The project aims to support developing countries in the implementation of the Rotterdam and Stockholm Conventions, create human resources and institutional capacities and to demonstrate via pilot measures how chemical safety in the partner countries can be improved and sustainably implemented in line with international standards. With this objective the development of a Chemical Management Guide (CM Guide) for small and medium-sized enterprises in developing countries has been initiated. The guide describes a step-by-step approach which is based on identifying 'hot-spots' as a first step, and making a chemical inventory as a second step. The third step is the continuous improvement of chemical management. In total, there are six tools that aim to support the chemical management process: basic concepts for risk assessment; description of control approaches; using material safety data sheets (MSDSs); risk phrases for hazardous substances; safety phrases for hazardous substances; symbols used for labelling hazardous substances. In the course of the test-implementation of the CM Guide in Indonesia, it was found that MSDSs were not available in most of the smaller companies. In contrast, medium-sized and larger companies do have more MSDSs available. It was also found that the way to engage the minds of company owners and managers is with economic arguments related to the loss, waste and expiry of materials, and quality standards expected from importing countries.

  18. Injection barrel with a tapered structure for a low speed and small size cryogenic hydrogen pellet in medium-sized plasma fusion devices

    NASA Astrophysics Data System (ADS)

    Motojima, G.; Sakamoto, R.; Okada, H.; Nagasaki, K.; Yamada, H.; Nakamura, Y.; Kado, S.; Kobayashi, S.; Konoshima, S.; Minami, T.; Ohshima, S.; Yamamoto, S.; Mizuuchi, T.; Mutoh, T.

    2016-10-01

    An injection barrel was designed and fabricated for a small size 0.8 mm cryogenic pellet with a low speed of 200-300 m/s in medium-sized plasma fusion devices. Pellet injection with pneumatic acceleration was examined using a conventional in situ technique. A tapered structure was applied in the downstream side of the injection barrel to satisfy the requirement of pellet speed reduction by expansion of the propellant gas. Shadowgraph and light gate measurements show that the intact pellets have speeds of 260 ± 30 m/s and a typical size of 1.1-1.2 mm. The pellet ablation code based on a neutral gas shielding model shows that the penetration depth of the measured pellet parameters does not cross the plasma center, even in medium-sized plasma devices such as the Heliotron J helical device. The injection barrel with a tapered structure developed in this study is feasible for low speed pellet injection.

  19. Development of a large-scale isolation chamber system for the safe and humane care of medium-sized laboratory animals harboring infectious diseases*

    PubMed Central

    Pan, Xin; Qi, Jian-cheng; Long, Ming; Liang, Hao; Chen, Xiao; Li, Han; Li, Guang-bo; Zheng, Hao

    2010-01-01

    The close phylogenetic relationship between humans and non-human primates makes non-human primates an irreplaceable model for the study of human infectious diseases. In this study, we describe the development of a large-scale automatic multi-functional isolation chamber for use with medium-sized laboratory animals carrying infectious diseases. The isolation chamber, including the transfer chain, disinfection chain, negative air pressure isolation system, animal welfare system, and the automated system, is designed to meet all biological safety standards. To create an internal chamber environment that is completely isolated from the exterior, variable frequency drive blowers are used in the air-intake and air-exhaust system, precisely controlling the filtered air flow and providing an air-barrier protection. A double door transfer port is used to transfer material between the interior of the isolation chamber and the outside. A peracetic acid sterilizer and its associated pipeline allow for complete disinfection of the isolation chamber. All of the isolation chamber parameters can be automatically controlled by a programmable computerized menu, allowing for work with different animals in different-sized cages depending on the research project. The large-scale multi-functional isolation chamber provides a useful and safe system for working with infectious medium-sized laboratory animals in high-level bio-safety laboratories. PMID:20872984

  20. Vaccine Pipeline Has Grown During The Past Two Decades With More Early-Stage Trials From Small And Medium-Size Companies.

    PubMed

    Hwang, Thomas J; Kesselheim, Aaron S

    2016-02-01

    Many serious diseases lack safe and effective vaccines. Using a large commercial database, we examined trends in global vaccine research and development and found that the proportion of new vaccine candidates entering all stages of clinical development increased by 3-5 percentage points over the past two decades. Small and medium-size companies accounted for nearly twice as many new Phase I vaccine trials compared to large companies, but late-stage (Phase III) vaccine trials were dominated by large companies. There were no significant differences between vaccines and drugs in the probability of success in clinical trials or in profitability. Small and medium-size companies, including spin-outs from academic research centers, play an important role in innovative research and discovery. Our findings suggest that policy making targeted at smaller companies, such as prizes or opportunities for public-private partnerships, could support the development of new vaccines, particularly those targeting unmet medical needs and emerging public health threats.

  1. A signet-ring cell melanoma arising from a medium-sized congenital melanocytic nevus in an adult: A case report and literature review.

    PubMed

    Tajima, Shogo; Koda, Kenji

    2015-07-01

    Patients with congenital nevus, especially giant congenital melanocytic nevus (CMN) measuring >20 cm, are known to be at elevated risk of developing melanomas, especially during the first and second decades of life. Melanomas rarely develop in patients with small and medium-sized CMNs, but if they do, they occur during the fourth and fifth decades of life. We present a case of a rapidly enlarging signet-ring cell melanoma (over 3 months) that arose from a medium-sized CMN in a 57-year-old Japanese man. Only 11 other cases of signet-ring cell melanomas at the primary site have been reported. On the basis of morphology alone, it is difficult to diagnose a nodule appearing in a CMN as a signet-ring cell melanoma, because even a benign melanocytic nevus can appear as signet-ring cell morphology. Moreover, a rapidly growing proliferative nodule (PN) more often develops in a CMN than melanoma; PNs may at times exhibit enough atypia to be comparable to melanomas. In our case, loss of p16 expression in the melanoma distinguished it from the nevus cells and was helpful in making the correct diagnosis. Clinical information, such as the patient's age, was also useful in establishing the diagnosis.

  2. 78 FR 15674 - Fisheries of the Northeastern United States; Proposed 2013-2015 Spiny Dogfish Fishery Specifications

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-03-12

    ... United States; Proposed 2013-2015 Spiny Dogfish Fishery Specifications AGENCY: National Marine Fisheries... for the spiny dogfish fishery for the 2013-2015 fishing years. The proposed action was developed by... requirements of the Spiny Dogfish Fishery Management Plan. The proposed management measures are supported...

  3. The Cairo spiny mouse Acomys cahirinus shows a strong affinity to the Mongolian gerbil Meriones unguiculatus.

    PubMed

    Agulnik, S I; Silver, L M

    1996-01-01

    The classification of the African spiny mice (genus Acomys) within the Muridae family of rodents has been fraught with controversy. Morphological data suggest a close affinity between this group and true old world mice of the genus Mus. However, the combined results of immunological, biochemical, and DNA melting studies suggest that spiny mice should not even be considered as members of the Murinae subfamily. To further elucidate the position of the spiny mice within the rodent phylogenetic tree, we performed a direct sequence comparison of a 583-nucleotide homologous region from the spiny mouse type species Acomys cahirinus and five other representative rodent species. Our results provide incontrovertible evidence to support the contention that the spiny mouse is more closely related to the Mongolian gerbil Meriones unguiculatus than it is to Mus musculus.

  4. [Analysis of workplace health promotion and its effect on work ability and health-related quality of life in a medium-sized business].

    PubMed

    Biallas, B; Froböse, I; Zöller, M; Wilke, C

    2015-05-01

    This study analyses the effect of workplace health promotion on work ability and health-related quality of life in white-collar and blue-collar workers in a medium-sized business. The intervention group contains 75 subjects with a mean age of 36.6±10.63 years (55 men, 20 women). The participation rate is 47%. White-collar workers show improvement in their health-related quality of life regarding physical and psychological aspects and work ability. Physically inactive employees show improvement in their health-related quality of life regarding physical and psychological aspects as well as context. Active employees only show significant improvement in terms of work ability. In conclusion, the promotion of exercise in the context of occupational health promotion has a positive effect on quality of life and work ability of employees and, thus, is a benefit for both the individual as well as the business itself.

  5. Report: Maximizing recycling participation to reduce waste to landfill: a study of small to medium-sized enterprises in Hobart, Tasmania, Australia.

    PubMed

    Parsons, Sam; Kriwoken, Lorne K

    2010-05-01

    Small to medium-sized enterprises (SMEs) in Hobart, Tasmania, Australia face many barriers to recycling participation. This study first investigated the volumes and types of waste produced by SMEs. Significant barriers were then identified and key motivators to recycle examined. Using the Australia New Zealand Standard of Industrial Classification, stratified sampling of SMEs (n = 436) was undertaken. Inadequate storage space, paucity of readily available information on recycling services and the lack of staff allocated to sort and recycle were identified as major barriers. Cardboard, paper and plastic waste were produced in large volumes with only a small percentage being recycled and these were identified as target areas for local government. Recommendations include the appointment of a dedicated recycling officer to maximize recycling participation for the reduction of waste to landfill and to undertake further research on minimizing recycling costs.

  6. Medium-sized Au40(SR)24 and Au52(SR)32 nanoclusters with distinct gold-kernel structures and spectroscopic features

    NASA Astrophysics Data System (ADS)

    Xu, Wen Wu; Li, Yadong; Gao, Yi; Zeng, Xiao Cheng

    2016-01-01

    We have analyzed the structures of two medium-sized thiolate-protected gold nanoparticles (RS-AuNPs) Au40(SR)24 and Au52(SR)32 and identified the distinct structural features in their Au kernels [Sci. Adv., 2015, 1, e1500425]. We find that both Au kernels of the Au40(SR)24 and Au52(SR)32 nanoclusters can be classified as interpenetrating cuboctahedra. Simulated X-ray diffraction patterns of the RS-AuNPs with the cuboctahedral kernel are collected and then compared with the X-ray diffraction patterns of the RS-AuNPs of two other prevailing Au-kernels identified from previous experiments, namely the Ino-decahedral kernel and icosahedral kernel. The distinct X-ray diffraction patterns of RS-AuNPs with the three different types of Au-kernels can be utilized as signature features for future studies of structures of RS-AuNPs. Moreover, the simulated UV/Vis absorption spectra and Kohn-Sham orbital energy-level diagrams are obtained for the Au40(SR)24 and Au52(SR)32, on the basis of time-dependent density functional theory computation. The extrapolated optical band-edges of Au40(SR)24 and Au52(SR)32 are 1.1 eV and 1.25 eV, respectively. The feature peaks in the UV/Vis absorption spectra of the two clusters can be attributed to the d --> sp electronic transition. Lastly, the catalytic activities of the Au40(SR)24 and Au52(SR)32 are examined using CO oxidation as a probe. Both medium-sized thiolate-protected gold clusters can serve as effective stand-alone nanocatalysts.We have analyzed the structures of two medium-sized thiolate-protected gold nanoparticles (RS-AuNPs) Au40(SR)24 and Au52(SR)32 and identified the distinct structural features in their Au kernels [Sci. Adv., 2015, 1, e1500425]. We find that both Au kernels of the Au40(SR)24 and Au52(SR)32 nanoclusters can be classified as interpenetrating cuboctahedra. Simulated X-ray diffraction patterns of the RS-AuNPs with the cuboctahedral kernel are collected and then compared with the X-ray diffraction patterns of the RS

  7. Automated payload and instruments for astrobiology research developed and studied by German medium-sized space industry in cooperation with European academia

    NASA Astrophysics Data System (ADS)

    Schulte, Wolfgang; Hofer, Stefan; Hofmann, Peter; Thiele, Hans; von Heise-Rotenburg, Ralf; Toporski, Jan; Rettberg, Petra

    2007-06-01

    For more than a decade Kayser-Threde, a medium-sized enterprise of the German space industry, has been involved in astrobiology research in partnership with a variety of scientific institutes from all over Europe. Previous projects include exobiology research platforms in low Earth orbit on retrievable carriers and onboard the Space Station. More recently, exobiology payloads for in situ experimentation on Mars have been studied by Kayser-Threde under ESA contracts, specifically the ExoMars Pasteur Payload. These studies included work on a sample preparation and distribution systems for Martian rock/regolith samples, instrument concepts such as Raman spectroscopy and a Life Marker Chip, advanced microscope systems as well as robotic tools for astrobiology missions. The status of the funded technical studies and major results are presented. The reported industrial work was funded by ESA and the German Aerospace Center (DLR).

  8. Retrospective Comparison of Intermediate-term Efficacy of 350 mm2 Glaucoma Drainage Implants and Medium-sized 230-250 mm2 Implants

    PubMed Central

    Meyer, Alissa M; Rodgers, Cooper D; Zou, Baiming; Rosenberg, Nicole C; Webel, Aaron D

    2017-01-01

    ABSTRACT Aim To compare the intermediate-term efficacy of a large surface area Baerveldt 350 mm2 glaucoma drainage device (GDD) with medium surface area implants (Baerveldt 250 mm2 and Molteno 3, 230, or 245 mm2). Design This is a retrospective, nonrandomized comparative trial. Materials and methods A total of 94 eyes of 94 patients of mixed glaucoma diagnoses without any prior glaucoma surgical procedures and who had undergone a glaucoma drainage implant surgery with either a large Baerveldt 350 mm2 GDD or a medium-sized GDD (Baerveldt 250 mm2 or Molteno 230 or 245 mm2) were reviewed for intraocular pressure (IOP), number of glaucoma medications, and visual acuity (VA) preoperatively, and at 1, 2, and 3 years postprocedure. Results No significant differences were found in mean IOP, number of glaucoma medications used, and VA at 1, 2, and 3 years postoperatively. The rate of additional glaucoma procedures was similar between the two groups. Conclusion There is no clear evidence that a larger implant surface area beyond 230 to 250 mm2 is advantageous in providing intermediate-term IOP control. Clinical significance It may be technically easier to surgically place a GDD that does not need to have its wings placed underneath the recti muscles, and the IOP results are similar. How to cite this article Meyer AM, Rodgers CD, Zou B, Rosenberg NC, Webel AD, Sherwood MB. Retrospective Comparison of Intermediate-term Efficacy of 350 mm2 Glaucoma Drainage Implants and Medium-sized 230-250 mm2 Implants. J Curr Glaucoma Pract 2017;11(1):8-15. PMID:28138212

  9. Monitoring the aeration efficiency and carbon footprint of a medium-sized WWTP: experimental results on oxidation tank and aerobic digester.

    PubMed

    Caivano, Marianna; Bellandi, Giacomo; Mancini, Ignazio M; Masi, Salvatore; Brienza, Rosanna; Panariello, Simona; Gori, Riccardo; Caniani, Donatella

    2017-03-01

    The efficiency of aeration systems should be monitored to guarantee suitable biological processes. Among the available tools for evaluating the aeration efficiency, the off-gas method is one of the most useful. Increasing interest towards reducing greenhouse gas (GHG) emissions from biological processes has resulted in researchers using this method to quantify N2O and CO2 concentrations in the off-gas. Experimental measurements of direct GHG emissions from aerobic digesters (AeDs) are not available in literature yet. In this study, the floating hood technique was used for the first time to monitor AeDs. The floating hood technique was used to evaluate oxygen transfer rates in an activated sludge (AS) tank of a medium-sized municipal wastewater treatment plant located in Italy. Very low values of oxygen transfer efficiency were found, confirming that small-to-medium-sized plants are often scarcely monitored and wrongly managed. Average CO2 and N2O emissions from the AS tank were 0.14 kgCO2/kgbCOD and 0.007 kgCO2,eq/kgbCOD, respectively. For an AeD, 3 × 10(-10) kgCO2/kgbCOD direct CO2 emissions were measured, while CO2,eq emissions from N2O were 4 × 10(-9) kgCO2,eq/kgbCOD. The results for the AS tank and the AeD were used to estimate the net carbon and energy footprint of the entire plant.

  10. Demise of spiny hopsage shrubs following summer wildfire: an authentic record

    SciTech Connect

    Rickard, W.H.; McShane, M.C.

    1984-01-01

    Spiny hopsage, Grayia spinosa, shrubs growing in a plant community dominated by greasewood, Sarcobatus vermiculatus, shrubs were destroyed by a summer wildfire. In the first season after the burn, greasewood shrubs sprouted, and by April of the second spring season, greasewood had restored about one-half of its preburn canopy cover. Spiny hopsage shrubs did not sprout and their demise is attributed to stressed growing conditions imposed by an alkaline-sodic rooting substrate. The demise of spiny hopsage would likely have gone unnoticed were it not for the existence of a permanently marked study plot. 11 references, 1 table.

  11. Nucleus Accumbens Dopamine D2-Receptor Expressing Neurons Control Behavioral Flexibility in a Place Discrimination Task in the IntelliCage

    ERIC Educational Resources Information Center

    Macpherson, Tom; Morita, Makiko; Wang, Yanyan; Sasaoka, Toshikuni; Sawa, Akira; Hikida, Takatoshi

    2016-01-01

    Considerable evidence has demonstrated a critical role for the nucleus accumbens (NAc) in the acquisition and flexibility of behavioral strategies. These processes are guided by the activity of two discrete neuron types, dopamine D1- or D2-receptor expressing medium spiny neurons (D1-/D2-MSNs). Here we used the IntelliCage, an automated…

  12. High- and medium-molecular-weight neurofilament proteins define specific neuron types in the guinea-pig enteric nervous system.

    PubMed

    Rivera, Leni R; Thacker, Michelle; Furness, John B

    2009-03-01

    Previous studies have demonstrated that neurofilament proteins are expressed by type II neurons in the enteric plexuses of a range of species from mouse to human. However, two previous studies have failed to reveal this association in the guinea-pig. Furthermore, immunohistochemistry for neurofilaments has revealed neurons with a single axon and spiny dendrites in human and pig but this morphology has not been described in the guinea-pig or other species. We have used antibodies against high- and medium-weight neurofilament proteins (NF-H and NF-M) to re-examine enteric neurons in the guinea-pig. NF-H immunoreactivity occurred in all type II neurons (identified by their IB4 binding) but these neurons were never NF-M-immunoreactive. On the other hand, 17% of myenteric neurons expressed NF-M. Many of these were uni-axonal neurons with spiny dendrites and nitric oxide synthase (NOS) immunoreactivity. NOS immunoreactivity occurred in surface expansions of the cytoplasm that did not contain neurofilament immunoreactivity. Thus, because of their NOS immunoreactivity, spiny neurons had the appearance of type I neurons. This indicates that the apparent morphologies and the morphological classifications of these neurons are dependent on the methods used to reveal them. We conclude that spiny type I NOS-immunoreactive neurons have similar morphologies in human and guinea-pig and that many of these are inhibitory motor neurons. Both type II and neuropeptide-Y-immunoreactive neurons in the submucosal ganglia exhibit NF-H immunoreactivity. NF-M has been observed in nerve fibres, but not in nerve cell bodies, in the submucosa.

  13. Follicular atresia in the prepubertal spiny mouse (Acomys cahirinus) ovary.

    PubMed

    Hułas-Stasiak, Monika; Gawron, Antoni

    2011-10-01

    This study was designed to determine follicular atresia in the newborn and the prepubertal spiny mouse. We analyzed the processes of follicle loss using classical markers of apoptosis (TUNEL reaction, active caspase-3) and autophagy (Lamp1). Numerous small clear vacuoles and autophagosomes as well as strong Lamp1 staining were observed in dying oocytes of all follicle types, especially of the primordial and primary ones. Active caspase 3 and the TUNEL reaction were detected only in the granulosa cells of large secondary and antral follicles. The expression of apoptosis and autophagy markers was also changing during the prepubertal period. Western blot analysis indicated that at the moment of birth, females undergo an increased rate of follicular atresia mediated by autophagy, while apoptosis is the dominant form of ovarian atresia in consecutive postnatal days. On the basis of these observations, we concluded that apoptosis and autophagy are involved in follicular atresia and these processes are cell and developmental stage-specific.

  14. Behavioral Immunity Suppresses an Epizootic in Caribbean Spiny Lobsters

    PubMed Central

    Butler, Mark J.; Behringer, Donald C.; Dolan, Thomas W.; Moss, Jessica; Shields, Jeffrey D.

    2015-01-01

    Sociality has evolved in a wide range of animal taxa but infectious diseases spread rapidly in populations of aggregated individuals, potentially negating the advantages of their social interactions. To disengage from the coevolutionary struggle with pathogens, some hosts have evolved various forms of “behavioral immunity”; yet, the effectiveness of such behaviors in controlling epizootics in the wild is untested. Here we show how one form of behavioral immunity (i.e., the aversion of diseased conspecifics) practiced by Caribbean spiny lobsters (Panulirus argus) when subject to the socially transmitted PaV1 virus, appears to have prevented an epizootic over a large seascape. We capitalized on a "natural experiment" in which a die-off of sponges in the Florida Keys (USA) resulted in a loss of shelters for juvenile lobsters over a ~2500km2 region. Lobsters were thus concentrated in the few remaining shelters, presumably increasing their exposure to the contagious virus. Despite this spatial reorganization of the population, viral prevalence in lobsters remained unchanged after the sponge die-off and for years thereafter. A field experiment in which we introduced either a healthy or PaV1-infected lobster into lobster aggregations in natural dens confirmed that spiny lobsters practice behavioral immunity. Healthy lobsters vacated dens occupied by PaV1-infected lobsters despite the scarcity of alternative shelters and the higher risk of predation they faced when searching for a new den. Simulations from a spatially-explicit, individual-based model confirmed our empirical results, demonstrating the efficacy of behavioral immunity in preventing epizootics in this system. PMID:26061629

  15. Parvalbumin-immunoreactive neurons in the human claustrum.

    PubMed

    Hinova-Palova, D V; Edelstein, L; Landzhov, B V; Braak, E; Malinova, L G; Minkov, M; Paloff, A; Ovtscharoff, W

    2014-09-01

    The morphology and distribution of parvalbumin-immunoreactive neurons (PV-ir) were studied in the human claustrum. PV-ir neurons were observed throughout the claustrum, with the highest numbers noted in the central (broadest) portion as compared with the dorsal and ventral aspects. Reaction product was evident in the neuronal perikarya, dendritic processes, and spines. In the majority of these labeled neurons, the cytoplasm was devoid of lipofuscin pigment. Cell bodies varied widely in both shape and size, ranging from oval and small, to multipolar and large. PV-ir neurons were classified into two groups, primarily based on dendritic morphology: spiny neurons with long and straight dendrites, and aspiny neurons with thin and curving dendritic processes. PV-ir fibers were seen throughout the neuropil, with many immuno-positive puncta noted.

  16. Search for global-minimum geometries of medium-sized germanium clusters. II. Motif-based low-lying clusters Ge21-Ge29

    NASA Astrophysics Data System (ADS)

    Yoo, S.; Zeng, X. C.

    2006-05-01

    We performed a constrained search for the geometries of low-lying neutral germanium clusters GeN in the size range of 21⩽N⩽29. The basin-hopping global optimization method is employed for the search. The potential-energy surface is computed based on the plane-wave pseudopotential density functional theory. A new series of low-lying clusters is found on the basis of several generic structural motifs identified previously for silicon clusters [S. Yoo and X. C. Zeng, J. Chem. Phys. 124, 054304 (2006)] as well as for smaller-sized germanium clusters [S. Bulusu et al., J. Chem. Phys. 122, 164305 (2005)]. Among the generic motifs examined, we found that two motifs stand out in producing most low-lying clusters, namely, the six/nine motif, a puckered-hexagonal-ring Ge6 unit attached to a tricapped trigonal prism Ge9, and the six/ten motif, a puckered-hexagonal-ring Ge6 unit attached to a bicapped antiprism Ge10. The low-lying clusters obtained are all prolate in shape and their energies are appreciably lower than the near-spherical low-energy clusters. This result is consistent with the ion-mobility measurement in that medium-sized germanium clusters detected are all prolate in shape until the size N ˜65.

  17. Organic–inorganic binary mixture matrix for comprehensive laser-desorption ionization mass spectrometric analysis and imaging of medium-size molecules including phospholipids, glycerolipids, and oligosaccharides

    DOE PAGES

    Feenstra, Adam D.; O'Neill, Kelly C.; Yagnik, Gargey B.; ...

    2016-10-13

    Matrix-assisted laser desorption/ionization mass spectrometry (MALDI-MS) is a widely adopted, versatile technique, especially in high-throughput analysis and imaging. However, matrix-dependent selectivity of analytes is often a severe limitation. In this work, a mixture of organic 2,5-dihydroxybenzoic acid and inorganic Fe3O4 nanoparticles is developed as a binary MALDI matrix to alleviate the well-known issue of triacylglycerol (TG) ion suppression by phosphatidylcholine (PC). In application to lipid standards and maize seed cross-sections, the binary matrix not only dramatically reduced the ion suppression of TG, but also efficiently desorbed and ionized a wide variety of lipids such as cationic PC, anionic phosphatidylethanolamine (PE)more » and phosphatidylinositol (PI), and neutral digalactosyldiacylglycerol (DGDG). The binary matrix was also very efficient for large polysaccharides, which were not detected by either of the individual matrices. As a result, the usefulness of the binary matrix is demonstrated in MS imaging of maize seed sections, successfully visualizing diverse medium-size molecules and acquiring high-quality MS/MS spectra for these compounds.« less

  18. Organic–inorganic binary mixture matrix for comprehensive laser-desorption ionization mass spectrometric analysis and imaging of medium-size molecules including phospholipids, glycerolipids, and oligosaccharides

    SciTech Connect

    Feenstra, Adam D.; O'Neill, Kelly C.; Yagnik, Gargey B.; Lee, Young Jin

    2016-10-13

    Matrix-assisted laser desorption/ionization mass spectrometry (MALDI-MS) is a widely adopted, versatile technique, especially in high-throughput analysis and imaging. However, matrix-dependent selectivity of analytes is often a severe limitation. In this work, a mixture of organic 2,5-dihydroxybenzoic acid and inorganic Fe3O4 nanoparticles is developed as a binary MALDI matrix to alleviate the well-known issue of triacylglycerol (TG) ion suppression by phosphatidylcholine (PC). In application to lipid standards and maize seed cross-sections, the binary matrix not only dramatically reduced the ion suppression of TG, but also efficiently desorbed and ionized a wide variety of lipids such as cationic PC, anionic phosphatidylethanolamine (PE) and phosphatidylinositol (PI), and neutral digalactosyldiacylglycerol (DGDG). The binary matrix was also very efficient for large polysaccharides, which were not detected by either of the individual matrices. As a result, the usefulness of the binary matrix is demonstrated in MS imaging of maize seed sections, successfully visualizing diverse medium-size molecules and acquiring high-quality MS/MS spectra for these compounds.

  19. Health-Related Quality of Life and Its Correlates among Chinese Migrants in Small- and Medium-Sized Enterprises in Two Cities of Guangdong

    PubMed Central

    Lu, Liming; Zou, Guanyang; Zeng, Zhi; Han, Lu; Guo, Yan; Ling, Li

    2014-01-01

    Objectives To explore the relationship between health-related quality of life (HRQOL) status and associated factors among rural-to-urban migrants in China. Methods A cross-sectional survey was conducted with 856 rural-to-urban migrants working at small- and medium-size enterprises (SMEs) in Shenzhen and Zhongshan City in 2012. Andersen's behavioral model was used as a theoretical framework to exam the relationships among factors affecting HRQOL. Analysis was performed using structural equation modeling (SEM). Results Workers with statutory working hours, higher wages and less migrant experience had higher HRQOL scores. Need (contracting a disease in the past two weeks and perception of needing health service) had the greatest total effect on HRQOL (β = −0.78), followed by enabling (labor contract, insurance purchase, income, physical examination during work and training) (β = 0.40), predisposing (age, family separation, education) (β = 0.22) and health practices and use of health service (physical exercise weekly, health check-up and use of protective equipments) (β = −0.20). Conclusions Priority should be given to satisfy the needs of migrant workers, and improve the enabling resources. PMID:24392084

  20. Medium-sized icy satellites in the outer solar system - differentiation due to radiogenic heating in Charon or the moons of Uranus?

    NASA Astrophysics Data System (ADS)

    Multhaup, K.; Spohn, T.

    2007-08-01

    A thermal history model developed for medium-sized icy satellites containing silicate rock at low volume fractions is applied to Charon and five satellites of Uranus. The model assumes stagnant lid convection in homogeneously accreted bodies either confined to a spherical shell or encompassing the whole interior below the immobile surface layer. We employ a simple model for accretion assuming that infalling planetesimals deposit a fraction of their kinetic energy as heat at the instantaneous surface of the growing moon. Rheology parameters are chosen to match those of ice I, although the satellites under consideration likely contain admixtures of lighter constituents. Consequences thereof are discussed. Thermal evolution calculations considering radiogenic heating by long-lived isotopes suggest that Ariel, Umbriel, Titania, Oberon and Charon may have started to differentiate after a few hundred million years of evolution. Results for Miranda - the smallest satellite of Uranus - however, indicate that it never convected or differentiated. Miranda's interior temperature was found to be not even close to the melting temperatures of reasonable mixtures of water and ammonia. This finding is in contrast to its heavily modified surface and supports theories that propose alternative heating mechanisms such as early tidal heating. Except for Miranda, our results lend support to differentiated icy satellite models. We also point out parallels to previously published results obtained for several of Saturn's icy satellites (Multhaup and Spohn, 2007). The predicted early histories of Ariel, Umbriel and Charon are evocative of Dione's and Rhea's, while Miranda's resembles that of Mimas.

  1. Locomotion in some small to medium-sized mammals: a geometric morphometric analysis of the penultimate lumbar vertebra, pelvis and hindlimbs.

    PubMed

    Álvarez, Alicia; Ercoli, Marcos D; Prevosti, Francisco J

    2013-12-01

    We assessed the influence of a variety of aspects of locomotion and ecology including gait and locomotor types, maximal running speed, home range, and body size on postcranial shape variation in small to medium-sized mammals, employing geometric morphometric analysis and phylogenetic comparative methods. The four views analyzed, i.e., dorsal view of the penultimate lumbar vertebra, lateral view of the pelvis, posterior view of the proximal femur and proximal view of the tibia, showed clear phylogenetic signal and interesting patterns of association with movement. Variation in home range size was related to some tibia shape changes, while speed was associated with lumbar vertebra, pelvis and tibia shape changes. Femur shape was not related to any locomotor variables. In both locomotor type and high-speed gait analyses, locomotor groups were distinguished in both pelvis and tibia shape analyses. These results suggest that adaptations to both typical and high-speed gaits could explain a considerable portion of the shape of those elements. In addition, lumbar vertebra and tibia showed non-significant relationships with body mass, which suggests that they might be used in morpho-functional analyses and locomotor inferences on fossil taxa, with little or no bias for body size. Lastly, we observed morpho-functional convergences among several mammalian taxa and detected some taxa that achieve similar locomotor features following different morphological paths.

  2. Analysis of Socio-demographics, Self-rated Health, Social Capital, and Happiness in a Medium-Sized Healthy City, Republic of Korea

    PubMed Central

    Jo, Heui Sug; Moon, Ji Young; Kim, Bong Gi; Nam, Eun Woo

    2015-01-01

    Background This study explores the relationships between social capital, self-rated health, and happiness and suggests ways to improve the happiness level of a community. Methods The survey was conducted with 445 people using stratified random sampling in a medium-sized city in Korea. Collected information included socio-demographic characteristics, social capital, self-rated health, and happiness. Results Among the demographic characteristics, age had a statistically significant association with happiness level. People in their 40s (OR = 0.33, 95% CI = 0.13–0.88) and 50s (OR = 0.19, 95% CI = 0.06–0.57) were less happy than people of other ages. Married people (OR = 4.58, CI = 1.99–10.53) were more likely to have a high happiness level compared to unmarried people. Cognitive social capital (OR = 1.34, CI = 1.19–1.51) and self-rated health (OR = 2.22, CI = 1.59–3.09) were positively associated with happiness. Conclusion The results suggest that social capital and level of health are determinants of subjective happiness. Public policies and programs for improving social capital are needed to support happiness among community residents. PMID:26770893

  3. A simulation study of the energy-efficient options for upgrading and retrofitting a medium-size municipal wastewater treatment plant.

    PubMed

    Mucha, Zbigniew; Mikosz, Jerzy

    2016-10-01

    Many municipal wastewater treatment plants are retrofitted with membrane filtration that replaces secondary clarification. Such a solution saves space and improves overall treatment efficiency but at the cost of increased energy consumption and reduced potential for energy recovery from sewage sludge. Thus, the plant takes a step back from reaching energy self-sufficiency. In the presented case study, two alternative upgrade options were simulated for a medium-size municipal wastewater treatment plant in Poland: the first one assumed optimization of the existing bioreactor, and the other - installation of microfiltration membrane units inside the bioreactor. In both cases, anaerobic digestion of waste sludge with biogas utilization is planned. The results have shown that while under both upgrade options, the plant's capacity can be effectively increased by approximately 50%, their effects on the plant's energy balance will be very different. Although the installation of membrane modules accompanied by the construction of anaerobic digestion tanks improves the plant's energy balance, it will remain negative. The option of optimizing the existing biological treatment system produces a positive energy balance with more energy produced from biogas than consumed. Thus, the plant is able to approach energy self-sufficiency. It has been concluded that retrofitting the plants with membrane filtration is not always the best option from the energy balance point of view and it should be preceded with a detailed analysis on a case-by-case basis.

  4. Ambient air levels of volatile organic compounds (VOC) and nitrogen dioxide (NO2) in a medium size city in Northern Spain.

    PubMed

    Parra, M A; Elustondo, D; Bermejo, R; Santamaría, J M

    2009-01-15

    Ambient concentrations of volatile organic compounds (VOC) and nitrogen dioxide (NO2) were measured by means of passive sampling at 40 sampling points in a medium-size city in Northern Spain, from June 2006 to June 2007. VOC and NO2 samplers were analysed by thermal desorption followed by gas chromatography/mass-selective detector and by visible spectrophotometry, respectively. Mean concentrations of benzene, toluene, ethylbenzene, xylenes, propylbenzene, trimethylbenzenes, and NO(2) were 2.84, 13.26, 2.15, 6.01, 0.59, 1.32 and 23.17 microg m(-3) respectively, and found to be highly correlated. Their spatial distribution showed high differences in small distances and pointed to traffic as the main emission source of these compounds. The lowest levels of VOC and NO2 occurred during summer, owing to the increase in solar radiation and to lower traffic densities. Mean concentrations of benzene and NO2 exceeded the European limits at some of the monitored points.

  5. The effect of air pollutants on birth weight in medium-sized towns in the state of São Paulo☆

    PubMed Central

    Santos, Veridiana de Paula; de Medeiros, Andréa Paula Peneluppi; de Lima, Thaiza Agostini Córdoba; Nascimento, Luiz Fernando Costa

    2014-01-01

    OBJECTIVE: To investigate the effect of air pollution on birth weight in a medium-sized town in the State of São Paulo, Southeast Brazil. METHODS: Cross-sectional study using data from live births of mothers residing in São José dos Campos from 2005 to 2009. Data was obtained from the Department of Information and Computing of the Brazilian Unified Health System. Air pollutant data (PM10, SO2, and O3) and daily averages of their concentrations were obtained from the Environmental Sanitation & Technology Company. Statistical analysis was performed by linear and logistic regressions using the Excel and STATA v.7 software programs. RESULTS: Maternal exposure to air pollutants was not associated with low birth weight, with the exception of exposure to SO2 within the last month of pregnancy (OR=1.25; 95% CI=1.00-1.56). Maternal exposure to PM10 and SO2 during the last month of pregnancy led to lower weight at birth (0.28g and 3.15g, respectively) for each 1mg/m3 increase in the concentration of these pollutants, but without statistical significance. CONCLUSIONS: This study failed to identify a statistically significant association between the levels of air pollutants and birth weight, with the exception of exposure to SO2 within the last month of pregnancy. PMID:25510993

  6. Global population structure of the spiny dogfish Squalus acanthias, a temperate shark with an antitropical distribution.

    PubMed

    Veríssimo, A; McDowell, J R; Graves, J E

    2010-04-01

    The spiny dogfish (Squalus acanthias) is a temperate, coastal squaloid shark with an antitropical distribution in the Atlantic and Pacific oceans. The global population structure of this species is poorly understood, although individuals are known to undergo extensive migrations within coastal waters and across ocean basins. In this study, an analysis of the global population structure of the spiny dogfish was conducted using eight polymorphic nuclear microsatellite markers and a 566-bp fragment of the mitochondrial ND2 gene region. A low level of genetic divergence was found among collections from the Atlantic and South Pacific basins, whereas a high level of genetic divergence was found among Pacific Ocean collections. Two genetically distinct groups were recovered by both marker classes: one exclusive to North Pacific collections, and one including collections from the South Pacific and Atlantic locations. The strong genetic break across the equatorial Pacific coincides with major regional differences in the life-history characters of spiny dogfish, suggesting that spiny dogfish in areas on either side of the Pacific equator have been evolving independently for a considerable time. Phylogeographic analyses indicate that spiny dogfish populations had a Pacific origin, and that the North Atlantic was colonized as a result of a recent range expansion from the South American coast. Finally, the available data strongly argue for the taxonomic separation of the North Pacific spiny dogfish from S. acanthias and a re-evaluation of the specific status of S. acanthias is warranted.

  7. The reproductive tract of the male spiny mouse (Acomys cahirinus) and coagulation studies with other species.

    PubMed

    Peitz, B; Foreman, D; Schmitt, M

    1979-09-01

    The testes of the spiny mice showed asymmetry, the left being significantly heavier than the right (P = 0.025). Histological studies indicated that spermatozoa were first present in the testes of animals 35--45 days of age but the maturation of the accessory glands, especially the lateral prostates and coagulating glands, occurred later. The highest fructose concentration in the adult was in the lateral prostates (126.97 +/- 22.23 mg fructose/100 g, n = 5) and coagulating glands (99.38 +/- 17.65 mg fructose/100 g gland weight, n = 5). Coagulation tests of mixtures of extracts of seminal vesicles and coagulating glands from spiny mice and rats indicated that the vesiculase of the spiny mouse was active on rat substrates and vice versa. Cross-reactions of extracts of house mouse (Mus musculus), hamster (Mesocricetus auratus), gerbil (Meriones unguiculatus), and guinea-pig (Cavia porcellus) seminal vesicles (substrate) and coagulating glands (vesiculase) with those of rats and spiny mice showed that although the substrates of rat and spiny mouse were readily coagulated by vesiculase from all the other species, rat and spiny mouse vesiculase were not equally active on substrates of the other species.

  8. The neocortex of cetartiodactyls: I. A comparative Golgi analysis of neuronal morphology in the bottlenose dolphin (Tursiops truncatus), the minke whale (Balaenoptera acutorostrata), and the humpback whale (Megaptera novaeangliae).

    PubMed

    Butti, Camilla; Janeway, Caroline M; Townshend, Courtney; Wicinski, Bridget A; Reidenberg, Joy S; Ridgway, Sam H; Sherwood, Chet C; Hof, Patrick R; Jacobs, Bob

    2015-11-01

    The present study documents the morphology of neurons in several regions of the neocortex from the bottlenose dolphin (Tursiops truncatus), the North Atlantic minke whale (Balaenoptera acutorostrata), and the humpback whale (Megaptera novaeangliae). Golgi-stained neurons (n = 210) were analyzed in the frontal and temporal neocortex as well as in the primary visual and primary motor areas. Qualitatively, all three species exhibited a diversity of neuronal morphologies, with spiny neurons including typical pyramidal types, similar to those observed in primates and rodents, as well as other spiny neuron types that had more variable morphology and/or orientation. Five neuron types, with a vertical apical dendrite, approximated the general pyramidal neuron morphology (i.e., typical pyramidal, extraverted, magnopyramidal, multiapical, and bitufted neurons), with a predominance of typical and extraverted pyramidal neurons. In what may represent a cetacean morphological apomorphy, both typical pyramidal and magnopyramidal neurons frequently exhibited a tri-tufted variant. In the humpback whale, there were also large, star-like neurons with no discernable apical dendrite. Aspiny bipolar and multipolar interneurons were morphologically consistent with those reported previously in other mammals. Quantitative analyses showed that neuronal size and dendritic extent increased in association with body size and brain mass (bottlenose dolphin < minke whale < humpback whale). The present data thus suggest that certain spiny neuron morphologies may be apomorphies in the neocortex of cetaceans as compared to other mammals and that neuronal dendritic extent covaries with brain and body size.

  9. Tyrosine hydroxylase immunoreactive neurons in the forebrain of the trout: organization, cellular features and innervation.

    PubMed

    Anadón, Ramón; Rodríguez-Moldes, Isabel; González, Agustín

    We studied the segmental distribution and cellular features of tyrosine hydroxylase-immunoreactive (TH-ir) neurons in the forebrain of trout. Large differences in cell size, general morphology, and complexity of cell processes were observed between TH-ir nuclei of different regions, and a new type of complex spiny TH-ir neurons in the ventral telencephalon is described for the first time. The distribution of TH-ir fibers was also analyzed and discussed.

  10. Predictors of a Desire to be Helpful to Professional Nurses Among Japanese Nursing Assistants in Small- to Medium-Sized Hospitals.

    PubMed

    Kudo, Yasushi; Kono, Keiko; Toyoshima, Yasuko; Sugisaki, Hitomi; Matsuhashi, Ayako; Tsutsumi, Akizumi

    2016-06-01

    Registered nurses and licensed practical nurses have been educated as professional nurses. Professional nurses can concentrate on their jobs requiring a high degree of expertise with help they get from nursing assistants.If professional nurses have improper attitudes toward nursing assistants, it is most likely that the nursing assistants will not help them to the best of their ability. We investigated nursing assistants' impressions regarding professional nurses' attitudes, and what effects nursing assistants' impressions have on their "desire to be helpful to professional nurses." The study design was a cross sectional study. Twenty-five small- to medium-sized hospitals with 55 to 458 beds were included in this study. The analyzed subjects were 642 nursing assistants (96 males, 546 females). Factor analyses were conducted to extract the factors of nursing assistants' impressions regarding professional nurses' attitudes. Multiple linear regression analysis was conducted to investigate the predictors of "desire to be helpful to professional nurses." We discovered 5 factors: 1. professional nurses' model behavior, 2. manner dealing with nursing assistants, 3. respect for nursing assistants' passion for their work, 4. respect for nursing assistants' work, and 5. enhancing the ability of nursing assistants to do their work. The "desire to be helpful to professional nurses" was significantly associated with "professional nurses' model behavior," "manner dealing with nursing assistants" and "respect for nursing assistants' passion for their work." Factors 1 to 3 are fundamental principles when people establish appropriate relationships. Professional nurses must consider these fundamentals in their daily work in order to get complete cooperation from nursing assistants.

  11. Decontamination efficacy of three commercial-off-the-shelf (COTS) sporicidal disinfectants on medium-sized panels contaminated with surrogate spores of Bacillus anthracis.

    PubMed

    Edmonds, Jason M; Sabol, Jonathan P; Rastogi, Vipin K

    2014-01-01

    In the event of a wide area release and contamination of a biological agent in an outdoor environment and to building exteriors, decontamination is likely to consume the Nation's remediation capacity, requiring years to cleanup, and leading to incalculable economic losses. This is in part due to scant body of efficacy data on surface areas larger than those studied in a typical laboratory (5×10-cm), resulting in low confidence for operational considerations in sampling and quantitative measurements of prospective technologies recruited in effective cleanup and restoration response. In addition to well-documented fumigation-based cleanup efforts, agencies responsible for mitigation of contaminated sites are exploring alternative methods for decontamination including combinations of disposal of contaminated items, source reduction by vacuuming, mechanical scrubbing, and low-technology alternatives such as pH-adjusted bleach pressure wash. If proven effective, a pressure wash-based removal of Bacillus anthracis spores from building surfaces with readily available equipment will significantly increase the readiness of Federal agencies to meet the daunting challenge of restoration and cleanup effort following a wide-area biological release. In this inter-agency study, the efficacy of commercial-of-the-shelf sporicidal disinfectants applied using backpack sprayers was evaluated in decontamination of spores on the surfaces of medium-sized (∼1.2 m2) panels of steel, pressure-treated (PT) lumber, and brick veneer. Of the three disinfectants, pH-amended bleach, Peridox, and CASCAD evaluated; CASCAD was found to be the most effective in decontamination of spores from all three panel surface types.

  12. The role of HIV/AIDS committees in effective workplace governance of HIV/AIDS in South African small and medium-sized enterprises (SMEs).

    PubMed

    Vaas, Jocelyn R

    2008-04-01

    The primary purpose of this study was to assess the role, status and scope of workplace HIV/AIDS committees as a means of effective workplace governance of the HIV/AIDS impact, and their role in extending social protective HIV/AIDS-related rights to employees. In-depth qualitative case studies were conducted in five South African small and medium-sized enterprises (SMEs) that were actively implementing HIV/AIDS policies and programmes. Companies commonly implemented HIV/AIDS policies and programmes through a workplace committee dedicated to HIV/AIDS or a generic committee dealing with issues other than HIV/ AIDS. Management, through the human resources department and the occupational health practitioner often drove initial policy formulation, and had virtually sole control of the HIV/AIDS budget. Employee members of committees were mostly volunteers, and were often production or blue collar employees, while there was a notable lack of participation by white-collar employees, line management and trade unions. While the powers of workplace committees were largely consultative, employee committee members often managed in an indirect manner to secure and extend social protective rights on HIV/AIDS to employees, and monitor their effective implementation in practice. In the interim, workplace committees represented one of the best means to facilitate more effective workplace HIV/AIDS governance. However, the increased demands on collective bargaining as a result of an anticipated rises in AIDS-related morbidity and mortality might prove to be beyond the scope of such voluntary committees in the longer term.

  13. The control system of the 12-m medium-size telescope prototype: a test-ground for the CTA array control

    NASA Astrophysics Data System (ADS)

    Oya, I.; Anguner, E. A.; Behera, B.; Birsin, E.; Fuessling, M.; Lindemann, R.; Melkumyan, D.; Schlenstedt, S.; Schmidt, T.; Schwanke, U.; Sternberger, R.; Wegner, P.; Wiesand, S.

    2014-07-01

    The Cherenkov Telescope Array (CTA) will be the next generation ground-based very-high energy -ray observatory. CTA will consist of two arrays: one in the Northern hemisphere composed of about 20 telescopes, and the other one in the Southern hemisphere composed of about 100 telescopes, both arrays containing telescopes of different sizes and types and in addition numerous auxiliary devices. In order to provide a test-ground for the CTA array control, the steering software of the 12-m medium size telescope (MST) prototype deployed in Berlin has been implemented using the tools and design concepts under consideration to be used for the control of the CTA array. The prototype control system is implemented based on the Atacama Large Millimeter/submillimeter Array (ALMA) Common Software (ACS) control middleware, with components implemented in Java, C++ and Python. The interfacing to the hardware is standardized via the Object Linking and Embedding for Process Control Unified Architecture (OPC UA). In order to access the OPC UA servers from the ACS framework in a common way, a library has been developed that allows to tie the OPC UA server nodes, methods and events to the equivalents in ACS components. The front-end of the archive system is able to identify the deployed components and to perform the sampling of the monitoring points of each component following time and value change triggers according to the selected configurations. The back-end of the archive system of the prototype is composed by two different databases: MySQL and MongoDB. MySQL has been selected as storage of the system configurations, while MongoDB is used to have an efficient storage of device monitoring data, CCD images, logging and alarm information. In this contribution, the details and conclusions on the implementation of the control software of the MST prototype are presented.

  14. Decontamination Efficacy of Three Commercial-Off-The-Shelf (COTS) Sporicidal Disinfectants on Medium-Sized Panels Contaminated with Surrogate Spores of Bacillus anthracis

    PubMed Central

    Sabol, Jonathan P.

    2014-01-01

    In the event of a wide area release and contamination of a biological agent in an outdoor environment and to building exteriors, decontamination is likely to consume the Nation’s remediation capacity, requiring years to cleanup, and leading to incalculable economic losses. This is in part due to scant body of efficacy data on surface areas larger than those studied in a typical laboratory (5×10-cm), resulting in low confidence for operational considerations in sampling and quantitative measurements of prospective technologies recruited in effective cleanup and restoration response. In addition to well-documented fumigation-based cleanup efforts, agencies responsible for mitigation of contaminated sites are exploring alternative methods for decontamination including combinations of disposal of contaminated items, source reduction by vacuuming, mechanical scrubbing, and low-technology alternatives such as pH-adjusted bleach pressure wash. If proven effective, a pressure wash-based removal of Bacillus anthracis spores from building surfaces with readily available equipment will significantly increase the readiness of Federal agencies to meet the daunting challenge of restoration and cleanup effort following a wide-area biological release. In this inter-agency study, the efficacy of commercial-of-the-shelf sporicidal disinfectants applied using backpack sprayers was evaluated in decontamination of spores on the surfaces of medium-sized (∼1.2 m2) panels of steel, pressure-treated (PT) lumber, and brick veneer. Of the three disinfectants, pH-amended bleach, Peridox, and CASCAD evaluated; CASCAD was found to be the most effective in decontamination of spores from all three panel surface types. PMID:24940605

  15. Detection of intermolecular transferred-NOE interactions in small and medium size protein complexes: RANTES complexed with a CCR5 N-terminal peptide.

    PubMed

    Abayev, Meital; Srivastava, Gautam; Arshava, Boris; Naider, Fred; Anglister, Jacob

    2017-02-01

    NMR is a powerful tool for studying structural details of protein/peptide complexes exhibiting weak to medium binding (KD > 10 μm). However, it has been assumed that intermolecular nuclear Overhauser effect (NOE) interactions are difficult to observe in such complexes. We demonstrate that intermolecular NOEs can be revealed by combining the (13) C-edited/(13) C-filtered experiment with the transferred NOE effect (TRNOE). Due to the TRNOE phenomenon, intermolecular NOE cross peaks are characterized by both the chemical shifts (CSs) of the protein protons and the average CSs of the peptide protons, which are dominated by the CSs of the protons of the free peptide. Previously, the TRNOE phenomenon was used almost exclusively to investigate the conformation of small ligands bound to large biomolecules. Here, we demonstrate that TRNOE can be extended to enable the study of intermolecular interactions in small- and medium-sized protein complexes. We used the (13) C-edited/(13) C-filtered TRNOE experiment to study the interactions of the chemokine regulated upon activation, normal T cell, expressed and secreted (RANTES) with a 27-residue peptide, containing two sulfotyrosine residues, representing the N-terminal segment of the CCR5 receptor ((Nt-CCR5(1-27). The TRNOE phenomenon led to more than doubling of the signal-to-noise ratios (SNRs) for the intermolecular NOEs observed in the (13) C-edited/(13) C-filtered experiment for the 11.5-kDa monomeric RANTES/Nt-CCR5(1-27) complex. An even better improvement in the SNR was achieved with dimeric Nt-CCR5(1-27)/RANTES (23 kDa), especially in comparison with the spectra measured with a 1 : 1 protein to peptide ratio. In principle, the isotope-edited/isotope-filtered TRNOE spectrum can discern all intermolecular interactions involving nonexchangeable protons in the complex.

  16. Adrenal steroidogenesis following prenatal dexamethasone exposure in the spiny mouse.

    PubMed

    Quinn, Tracey A; Ratnayake, Udani; Castillo-Melendez, Margie; Moritz, Karen M; Dickinson, Hayley; Walker, David W

    2014-05-01

    Antenatal stress disturbs the development of the fetal hypothalamic-pituitary-adrenal axis and adrenal steroidogenesis. We investigated the effect of brief maternal exposure to high glucocorticoids (dexamethasone (DEX)) at mid- and late-pregnancy on adrenal structure and production of steroids in spiny mouse. Pregnant spiny mice were treated for 60 h with 125 μg/kg DEX or saline s.c. by osmotic minipump at day 20 (0.5) or 30 (0.75) of gestation. Immunohistochemical expression of steroidogenic acute regulatory-protein (StAR), 3β-hydroxysteroid dehydrogenase (3βHSD), 17-hydroxylase,17-20lyase (P450C17), and cytochromeb5 (CYTB5) was determined in adrenals on postnatal (P) day 170±20. DHEA, testosterone, and cortisol were measured by RIA. Maternal DEX at 20 days significantly reduced the expression of STAR, P450C17 (CYP17A1), and CYTB5 in the adrenal zona reticularis (ZR) of adult offspring, with greater change in male vs female offspring (P<0.05). Plasma DHEA was decreased in male offspring from DEX-treated (6.84±1.24 ng/ml) vs saline-treated (13±0.06 ng/ml; P=0.01) dams, and the DHEA:cortisol ratio was lower in males (P<0.05). Testosterone levels increased in male offspring from DEX (266.03±50.75 pg/ml) vs saline (83.47±32.3 pg/ml, P<0.05)-treated dams. DEX treatment at 0.75 gestation had no significant effect on any parameters measured. This study shows that brief exposure to excess glucocorticoid has long-term impacts on the ZR and adrenal steroidogenesis, affecting the secretion of DHEA and testosterone in male offspring, an effect produced at 0.5 but not at 0.75 gestation. DHEA is important for brain development, and its suppression in adult life might contribute to the neurobehavioral pathologies that can arise after illness and stress during pregnancy.

  17. The Potential of Distance Education and Training for Small and Medium-Sized Enterprises in the Mediterranean Countries of the European Community. A Report for the Commission of the European Communities--Task Force Human Resources, Education, Training, and Youth.

    ERIC Educational Resources Information Center

    Quintino, Luisa

    An evaluation was made of the training needs of the small and medium-sized enterprises (SMEs) in Portugal, Spain, Greece, and Italy and the potential of open, distance, flexible, and multimedia learning to meet those needs. The methodology included contacts with training providers, governmental institutions, and SMEs and circulation of…

  18. Skin shedding and tissue regeneration in African spiny mice (Acomys)

    PubMed Central

    Seifert, Ashley W.; Kiama, Stephen G.; Seifert, Megan G.; Goheen, Jacob R.; Palmer, Todd M.; Maden, Malcolm

    2012-01-01

    SUMMARY Evolutionary modification has produced a spectrum of animal defense traits to escape predation, including the ability to autotomize body parts to elude capture1,2. Following autotomy, the missing part is either replaced through regeneration (e.g. urodeles, lizards, arthropods, crustaceans) or is permanently lost (mammals). While most autotomy involves the loss of appendages (e.g. leg, cheliped, antennae, tail), skin autotomy can occur in certain taxa of scincid and gekkonid lizards3. Here we report the first demonstration of skin autotomy in Mammalia (African spiny mice, Acomys). Mechanical testing revealed a propensity for skin to tear under very low tension and the absence of a fracture plane. Following skin loss, rapid wound contraction was followed by hair follicle regeneration in dorsal skin wounds. Surprisingly, we found regenerative capacity in Acomys extended to ear holes where they exhibited complete regeneration of hair follicles, sebaceous glands, dermis, and cartilage. Salamanders capable of limb regeneration form a blastema (a mass of lineage-restricted progenitor cells4) following limb loss, and our findings suggest that ear tissue regeneration in Acomys may proceed through assembly of a similar structure. This study underscores the importance of investigating regenerative phenomena outside of traditional model organisms and suggests that mammals may retain a higher capacity for regeneration than previously believed. As re-emergent interest in regenerative medicine seeks to isolate molecular pathways controlling tissue regeneration in mammals, Acomys may prove useful in identifying mechanisms to promote regeneration in lieu of fibrosis and scarring. PMID:23018966

  19. Endoparasites of the spiny mouse (Acomys spinosissimus) from South Africa.

    PubMed

    Lutermann, Heike; Medger, Katarina; Junker, Kerstin

    2014-02-01

    The endoparasite fauna of the spiny mouse (Acomys spinosissimus) was studied for the first time from April 2007 until April 2009 in a population from the Limpopo Province of South Africa. In a total of 129 mice examined, only 6 endoparasite taxa were found, 2 nematode species (Syphacia minuta, Monanema joopi), 1 genus of cestodes ( Rodentolepis spp.), and unidentified hymenolepidid fragments. In addition, 1 pentastomid species (Armillifer grandis) as well as unidentified porocephalid specimens were recovered. The overall prevalence was low, at 15.5%, and only 1 individual harbored more than 1 parasite species. With 12.4% prevalence, S. minuta was the most prevalent parasite. Its prevalence and abundance were significantly higher during the dry and cooler season than during the wet and warm season, while a female-biased burden was observed during the wet season only. For the remaining parasite species, low prevalence prevented meaningful statistical analyses. The observed parasite species richness, prevalence, and abundance for A. spinosissimus were low compared to values reported for other Acomys spp. This may be linked to the lack of anthropogenic influences in the study population as well as the small size of A. spinosissimus .

  20. Skin shedding and tissue regeneration in African spiny mice (Acomys).

    PubMed

    Seifert, Ashley W; Kiama, Stephen G; Seifert, Megan G; Goheen, Jacob R; Palmer, Todd M; Maden, Malcolm

    2012-09-27

    Evolutionary modification has produced a spectrum of animal defence traits to escape predation, including the ability to autotomize body parts to elude capture. After autotomy, the missing part is either replaced through regeneration (for example, in urodeles, lizards, arthropods and crustaceans) or permanently lost (such as in mammals). Although most autotomy involves the loss of appendages (legs, chelipeds, antennae or tails, for example), skin autotomy can occur in certain taxa of scincid and gekkonid lizards. Here we report the first demonstration of skin autotomy in Mammalia (African spiny mice, Acomys). Mechanical testing showed a propensity for skin to tear under very low tension and the absence of a fracture plane. After skin loss, rapid wound contraction was followed by hair follicle regeneration in dorsal skin wounds. Notably, we found that regenerative capacity in Acomys was extended to ear holes, where the mice exhibited complete regeneration of hair follicles, sebaceous glands, dermis and cartilage. Salamanders capable of limb regeneration form a blastema (a mass of lineage-restricted progenitor cells) after limb loss, and our findings suggest that ear tissue regeneration in Acomys may proceed through the assembly of a similar structure. This study underscores the importance of investigating regenerative phenomena outside of conventional model organisms, and suggests that mammals may retain a higher capacity for regeneration than was previously believed. As re-emergent interest in regenerative medicine seeks to isolate molecular pathways controlling tissue regeneration in mammals, Acomys may prove useful in identifying mechanisms to promote regeneration in lieu of fibrosis and scarring.

  1. Venezuelan equine encephalitis virus infection of spiny rats.

    PubMed

    Carrara, Anne-Sophie; Gonzales, Gonzales; Ferro, Cristina; Tamayo, Margarita; Aronson, Judith; Paessler, Slobodan; Anishchenko, Michael; Boshell, Jorge; Weaver, Scott C

    2005-05-01

    Enzootic strains of Venezuelan equine encephalitis virus (VEEV) circulate in forested habitats of Mexico, Central, and South America, and spiny rats (Proechimys spp.) are believed to be the principal reservoir hosts in several foci. To better understand the host-pathogen interactions and resistance to disease characteristic of many reservoir hosts, we performed experimental infections of F1 progeny from Proechimys chrysaeolus collected at a Colombian enzootic VEEV focus using sympatric and allopatric virus strains. All animals became viremic with a mean peak titer of 3.3 log10 PFU/mL, and all seroconverted with antibody titers from 1:20 to 1:640, which persisted up to 15 months. No signs of disease were observed, including after intracerebral injections. The lack of detectable disease and limited histopathologic lesions in these animals contrast dramatically with the severe disease and histopathologic findings observed in other laboratory rodents and humans, and support their role as reservoir hosts with a long-term coevolutionary relationship to VEEV.

  2. Mitogenomic Phylogeny, Diversification, and Biogeography of South American Spiny Rats.

    PubMed

    Fabre, Pierre-Henri; Upham, Nathan S; Emmons, Louise H; Justy, Fabienne; Leite, Yuri L R; Carolina Loss, Ana; Orlando, Ludovic; Tilak, Marie-Ka; Patterson, Bruce D; Douzery, Emmanuel J P

    2017-03-01

    Echimyidae is one of the most speciose and ecologically diverse rodent families in the world, occupying a wide range of habitats in the Neotropics. However, a resolved phylogeny at the genus-level is still lacking for these 22 genera of South American spiny rats, including the coypu (Myocastorinae), and 5 genera of West Indian hutias (Capromyidae) relatives. Here, we used Illumina shotgun sequencing to assemble 38 new complete mitogenomes, establishing Echimyidae, and Capromyidae as the first major rodent families to be completely sequenced at the genus-level for their mitochondrial DNA. Combining mitogenomes and nuclear exons, we inferred a robust phylogenetic framework that reveals several newly supported nodes as well as the tempo of the higher level diversification of these rodents. Incorporating the full generic diversity of extant echimyids leads us to propose a new higher level classification of two subfamilies: Euryzygomatomyinae and Echimyinae. Of note, the enigmatic Carterodon displays fast-evolving mitochondrial and nuclear sequences, with a long branch that destabilizes the deepest divergences of the echimyid tree, thereby challenging the sister-group relationship between Capromyidae and Euryzygomatomyinae. Biogeographical analyses involving higher level taxa show that several vicariant and dispersal events impacted the evolutionary history of echimyids. The diversification history of Echimyidae seems to have been influenced by two major historical factors, namely (1) recurrent connections between Atlantic and Amazonian Forests and (2) the Northern uplift of the Andes.

  3. Effects of noise on models of spiny dendrites.

    PubMed

    Coutts, Emma J; Lord, Gabriel J

    2013-04-01

    We study the effects of noise in two models of spiny dendrites. Through the introduction of different types of noise to both the Spike-diffuse-spike (SDS) and Baer-Rinzel (BR) models we investigate the change in behaviour of the travelling wave solution present in both deterministic systems, as noise intensity increases. We show that the speed of wave propagation in both the SDS and BR models respectively differs as the noise intensity in the spine heads increases. In contrast the cable is very robust to noise and as such the speed shows very little variation from the deterministic system. We introduce a space-dependent spine density, ρ(x), to the original Baer-Rinzel model and show how this modified model can mimic behaviour (under influence of noise) of both original systems, through variation of one parameter. We also show that the correlation time and length scales of the noise can enhance propagation of travelling wave solutions where the white noise dominates the underlying signal and produces noise induced phenomena.

  4. Excitatory inputs to spiny cells in layers 4 and 6 of cat striate cortex.

    PubMed Central

    Bannister, N J; Nelson, J C; Jack, J J B

    2002-01-01

    The principal target of lateral geniculate nucleus in the cat visual cortex is the stellate neurons of layer 4. In previously reported work with intracellular recording and extracellular stimulation in slices of visual cortex, three general classes of fast excitatory synaptic potentials (EPSPs) in layer 4a spiny stellate neurons were identified. One of these classes, characterized by large and relatively invariant amplitudes (mean 1.7 mV, average coefficient of variation (CV) 0.083) were attributed to the action of geniculate axons because, unlike the other two classes, they could not be matched by intracortical inputs, using paired recording. We have examined in detail the properties of this synaptic input in twelve examples, selecting for study those EPSPs where there was secure extracellular stimulation of the single fibre input to a pair of stimuli 50 ms apart. In our analysis, we conclude that the depression that these inputs show to the second stimulus is entirely postsynaptic, since the evidence strongly suggests that the probability of transmitter release at the synaptic site(s) remains 1.0 for both stimuli. We argue that the most plausible explanation for this postsynaptic depression is a reduction in the average probability of opening the synaptic channels. Using a simple biochemical analysis (c.f. Sigworth plot), it is then possible to calculate the number of synaptic channels and their probability of opening, for each of the 12 connections. The EPSPs had a mean amplitude of 1.91 mV (+/- 1.3 mV SD) and a mean CV of 0.067 (+/- 0.022). The calculated number of channels ranged from 20 to 158 (59.4 +/- 48.7) and their probability of opening to the first EPSP had an average of 0.83 (+/- 0.09), with an average depression of the probability to 0.60 for the second EPSP. Geniculate afferents also terminate in layer 6. Intracellular recordings were also made in the upper part of this layer and a total of 51 EPSPs were recorded from pyramidal cells of three

  5. Two strategies for coping with food shortage in desert golden spiny mice.

    PubMed

    Gutman, Roee; Yosha, Dotan; Choshniak, Itzhak; Kronfeld-Schor, Noga

    2007-01-30

    Desert rodents face periods of food shortage and use different strategies for coping with it, including changes in activity level. Golden spiny mice (Acomys russatus) inhabit rock crevasses and do not dig burrows nor store food. When kept under 50% food restriction most, but not all, golden spiny mice defend their body mass by physiological means. We tested the hypothesis that these rodents use two different behavioral strategies, i.e., increasing activity level and searching for food or decreasing activity level and conserving energy to cope with food shortage. Twelve golden spiny mice were fed ad libitum for 14 days, followed by 40 days of 50% food restriction, and 14 days of refeeding. Body mass, food consumption and general activity were monitored. Seven mice significantly reduced activity level, concentrating their activity around feeding time, lowering energy expenditure and thus keeping their body mass constant ("resistant"), while five ("non-resistant") significantly increased activity level (possibly searching for food) and thus energy expenditure, thereby losing mass rapidly (more than 25% of body mass). The non-resistant golden spiny mice were active throughout many hours of the day, with high variability both between and among individuals. The use of two strategies to cope with food shortage as found in the golden spiny mice may be of evolutionary advantage, since it allows a more flexible reaction to food restriction at the population level.

  6. Targeting single neuronal networks for gene expression and cell labeling in vivo.

    PubMed

    Marshel, James H; Mori, Takuma; Nielsen, Kristina J; Callaway, Edward M

    2010-08-26

    To understand fine-scale structure and function of single mammalian neuronal networks, we developed and validated a strategy to genetically target and trace monosynaptic inputs to a single neuron in vitro and in vivo. The strategy independently targets a neuron and its presynaptic network for specific gene expression and fine-scale labeling, using single-cell electroporation of DNA to target infection and monosynaptic retrograde spread of a genetically modifiable rabies virus. The technique is highly reliable, with transsynaptic labeling occurring in every electroporated neuron infected by the virus. Targeting single neocortical neuronal networks in vivo, we found clusters of both spiny and aspiny neurons surrounding the electroporated neuron in each case, in addition to intricately labeled distal cortical and subcortical inputs. This technique, broadly applicable for probing and manipulating single neuronal networks with single-cell resolution in vivo, may help shed new light on fundamental mechanisms underlying circuit development and information processing by neuronal networks throughout the brain.

  7. Medium-Sized Mammals around a Radioactive Liquid Waste Lagoon at Los Alamos National Laboratory: Uptake of Contaminants and Evaluation of Radio-Frequency Identification Technology

    SciTech Connect

    Leslie A. Hansen; Phil R. Fresquez; Rhonda J. Robinson; John D. Huchton; Teralene S. Foxx

    1999-11-01

    Use of a radioactive liquid waste lagoon by medium-sized mammals and levels of tritium, other selected radionuclides, and metals in biological tissues of the animals were documented at Technical Area 53 (TA-53) of Los Alamos National Laboratory during 1997 and 1998. Rock squirrel (Spermophilus variegates), raccoon (Procyon lotor), striped skunk (Mephitis mephitis), and bobcat (Lynx rufus) were captured at TA-53 and at a control site on the Santa Fe National Forest. Captured animals were anesthetized and marked with radio-frequency identification (RFD) tags and/or ear tags. We collected urine and hair samples for tritium and metals (aluminum, antimony, arsenic, barium, beryllium, cadmium, chromium, copper, lead, mercury, nickel, selenium, silver, and thallium) analyses, respectively. In addition, muscle and bone samples from two rock squirrels collected from each of TA-53, perimeter, and regional background sites were tested for tritium, {sup 137}Cs, {sup 90}Sr, {sup 238}Pu, {sup 239,240}Pu, {sup 241}Am, and total uranium. Animals at TA-53 were monitored entering and leaving the lagoon area using a RFID monitor to read identification numbers from the RFID tags of marked animals and a separate camera system to photograph all animals passing through the monitor. Cottontail rabbit (Sylvilagus spp.), rock squirrel, and raccoon were the species most frequently photographed going through the RFID monitor. Less than half of all marked animals in the lagoon area were detected using the lagoon. Male and female rock squirrels from the lagoon area had significantly higher tritium concentrations compared to rock squirrels from the control area. Metals tested were not significantly higher in rock squirrels from TA-53, although there was a trend toward increased levels of lead in some individuals at TA-53. Muscle and bone samples from squirrels in the lagoon area appeared to have higher levels of tritium, total uranium, and {sup 137}Cs than samples collected from perimeter and

  8. Effect of grid size in RCMs on the representation of floods in small and medium sized catchments in Austria: added value of convection-permitting simulations

    NASA Astrophysics Data System (ADS)

    Reszler, Christian; Truhetz, Heimo; Switanek, Matthew

    2016-04-01

    This paper presents a small multi-model ensemble study of coupling two different ERA-Interim driven RCMs (WRF and COSMO-CLM) using different grid sizes (0.44°, 0.11°, 0.03°) with a hydrological model for representing floods in small to medium sized catchments in South-eastern Austria. The aim is to evaluate the benefit of grid size reduction and in particular, the added value of convection-permitting simulations with 0.03° (~ 3 km) resolution. The hydrological model is a spatially distributed model (1 km² grid), which was previously developed for operational flood forecasting and calibrated against data of more than 20 stream gauges with corresponding catchment sizes between 30 and 1000 km². The hindcast simulations (1989-2010) are evaluated in terms of accurately representing flood frequency, seasonality, as well as other flood event characteristics, such as weather type, antecedent soil moisture, etc. The results show, that for small catchments (< 200 km²) a resolution of 3 km is essential to accurately simulate the magnitude of flood events. Flood frequency and seasonality is represented well in all catchments. In the larger catchments a resolution of 0.11° (~ 12.5 km) already yields statistically satisfying results. Also, due to the short response times in the small sub-catchments a time step of 1 hour is required. However, in all setups a bias still exists in precipitation and temperature, which sometimes leads to unrealistic hydrological conditions. Ongoing work comprises the test a of novel statistical error correction method, which is expected to improve results particularly for higher quantiles. Also, a future run ("time-slice" experiment) is planned with the coupled model setup using the RCP8.5 emission scenario, the GCM of the Max-Planck-Institute Hamburg (MPI-ESM-LR), dynamically downscaled to 3 km by COSMO-CLM, and the novel error correction method. The study is funded by the Austrian Klima- und Energiefonds through the Austrian Climate

  9. 76 FR 54727 - Fisheries of the Caribbean, Gulf of Mexico, and South Atlantic; Spiny Lobster Fishery of the Gulf...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-09-02

    ... Caribbean, Gulf of Mexico, and South Atlantic; Spiny Lobster Fishery of the Gulf of Mexico and South... Fishery Management Plan for the Spiny Lobster Fishery of the Gulf of Mexico and South Atlantic (FMP) for review, approval, and implementation by NMFS. Amendment 10 proposes actions to revise the lobster...

  10. 77 FR 50642 - Spiny Lobster Fishery of the Gulf of Mexico and South Atlantic; Amendment 11; Correction

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-08-22

    ... National Oceanic and Atmospheric Administration 50 CFR Part 640 RIN 0648-BB44 Spiny Lobster Fishery of the... Management Plan for the Spiny Lobster Fishery in the Gulf of Mexico and South Atlantic Regions that published...: Correction On July 27, 2012 (77 FR 44168, July 27, 2012), incorrect latitudinal coordinates for Lobster...

  11. 76 FR 82413 - Amendments to the Reef Fish, Spiny Lobster, Queen Conch and Coral and Reef Associated Plants and...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-12-30

    ... Part 622 Amendments to the Reef Fish, Spiny Lobster, Queen Conch and Coral and Reef Associated Plants... Amendments to the Reef Fish, Spiny Lobster, Queen Conch and Coral and Reef Associated Plants and... FMP), and Amendment 3 to the FMP for Corals and Reef Associated Plants and Invertebrates of...

  12. 76 FR 59377 - Amendments to the Reef Fish, Spiny Lobster, Queen Conch and Coral and Reef Associated Plants and...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-09-26

    ..., Spiny Lobster, Queen Conch and Coral and Reef Associated Plants and Invertebrates Fishery Management... Fishery Management Plans (FMPs) for Reef Fish Resources, Spiny Lobster, Queen Conch, and Coral and Reef... and coral and reef associated plants and invertebrates species. The 2011 Caribbean ACL Amendment...

  13. Observations on spiny dogfish ( Squalus acanthias) captured in late spring in a North Carolina estuary.

    PubMed

    Bangley, Charles; Rulifson, Roger

    2014-01-01

    Five spiny dogfish were captured in early-mid May during gillnet and longline sampling targeting juvenile coastal sharks in inshore North Carolina waters.  Dogfish captures were made within Back Sound and Core Sound, North Carolina. All dogfish were females measuring 849-905 mm total length, well over the size at 50% maturity. Dogfish were caught at stations 1.8-2.7 m in depth, with temperatures 22.9-24.2 °C, 32.8-33.4 ppt salinity, and 6.9-8.0 mg/L dissolved oxygen. These observations are among the latest in the spring for spiny dogfish in the southeastern U.S. and occurred at higher temperatures than previously recorded for this species.  It is unclear whether late-occurring spiny dogfish in this area represent a cryptic late-migrating or resident segment of the Northwest Atlantic population.

  14. Nutritional value of spiny lobsters (Panulirus sp.) from Southern Coast of Java

    NASA Astrophysics Data System (ADS)

    Haryono, F. Eko Dwi; Hutabarat, Sahala; Hutabarat, Johannes; Ambariyanto

    2015-12-01

    Five species of spiny lobsters are known to live in southern coast of Java. These lobsters are very popular seafood which was believed to have high nutritional value. However, nutrition content of these species from the area has not been investigated. This research was conducted to study nutrition content in these crustaceans. Five spiny lobsters i.e. Panulirus homarus, P. versicolor, P. ornatus, P. penicullatus, and P. longipes, were collected randomly from different locations at the southern coast of Java. Morphometric measurements were conducted prior to proximate analysis of these lobsters. All species of spiny lobsters investigated have similar carapace length. However, P. homarus and P. versicolor have the highest muscle weight. Proximate analysis shows that P. homarus also has high protein (24.18%) and carbohydrate content (55.68%) and lowest lipid content (6.18%) compare with other species. These results suggest that this lobster has best nutritional value for consumption.

  15. Observations on spiny dogfish ( Squalus acanthias) captured in late spring in a North Carolina estuary

    PubMed Central

    Bangley, Charles; Rulifson, Roger

    2014-01-01

    Five spiny dogfish were captured in early-mid May during gillnet and longline sampling targeting juvenile coastal sharks in inshore North Carolina waters.  Dogfish captures were made within Back Sound and Core Sound, North Carolina. All dogfish were females measuring 849-905 mm total length, well over the size at 50% maturity. Dogfish were caught at stations 1.8-2.7 m in depth, with temperatures 22.9-24.2 °C, 32.8-33.4 ppt salinity, and 6.9-8.0 mg/L dissolved oxygen. These observations are among the latest in the spring for spiny dogfish in the southeastern U.S. and occurred at higher temperatures than previously recorded for this species.  It is unclear whether late-occurring spiny dogfish in this area represent a cryptic late-migrating or resident segment of the Northwest Atlantic population. PMID:25469229

  16. Cell-type-specific resonances shape the responses of striatal neurons to synaptic input

    PubMed Central

    Beatty, Joseph A.; Song, Soomin C.

    2014-01-01

    Neurons respond to synaptic inputs in cell-type-specific ways. Each neuron type may thus respond uniquely to shared patterns of synaptic input. We applied statistically identical barrages of artificial synaptic inputs to four striatal cell types to assess differences in their responses to a realistic input pattern. Each interneuron type fired in phase with a specific input-frequency component. The fast-spiking interneuron fired in relation to the gamma-band (and higher) frequencies, the low-threshold spike interneuron to the beta-band frequencies, and the cholinergic neurons to the delta-band frequencies. Low-threshold spiking and cholinergic interneurons showed input impedance resonances at frequencies matching their spiking resonances. Fast-spiking interneurons showed resonance of input impedance but at lower than gamma frequencies. The spiny projection neuron's frequency preference did not have a fixed frequency but instead tracked its own firing rate. Spiny cells showed no input impedance resonance. Striatal interneurons are each tuned to a specific frequency band corresponding to the major frequency components of local field potentials. Their influence in the circuit may fluctuate along with the contribution of that frequency band to the input. In contrast, spiny neurons may tune to any of the frequency bands by a change in firing rate. PMID:25411465

  17. Disposition of phenanthrene and octachlorostyrene in spiny lobsters, Panulirus argus, after intragastric administration

    SciTech Connect

    Solbakken, J.E.; Knap, A.H.

    1986-11-01

    Spiny lobster (Panulirus argus) is a commercial crustacean in Bermuda. It was therefore of interest to study the fate of xenobiotics in the species as very little attention has been paid to toxicological studies with spiny lobsters. Earlier it was found that the temperate crustacean, Nephrops norveqicus (Norway lobster) had the ability to accumulate and eliminate phenanthrene. The aim of this investigation was to gain a better understanding of the fate of xenobiotics in crustaceans under different environmental conditions, and to compare the polycyclic aromatic hydrocarbon, phenenthrene, with the more environmentally persistent chlorinated compound octachlorostyrene, a by-product of magnesium metal production.

  18. A matched cohort comparison of clinical outcomes following microsurgical resection or stereotactic radiosurgery for patients with small- and medium-sized vestibular schwannomas.

    PubMed

    Golfinos, John G; Hill, Travis C; Rokosh, Rae; Choudhry, Osamah; Shinseki, Matthew; Mansouri, Alireza; Friedmann, David R; Thomas Roland, J; Kondziolka, Douglas

    2016-12-01

    OBJECTIVE A randomized trial that compares clinical outcomes following microsurgery (MS) or stereotactic radiosurgery (SRS) for patients with small- and medium-sized vestibular schwannomas (VSs) is impractical, but would have important implications for clinical decision making. A matched cohort analysis was conducted to evaluate clinical outcomes in patients treated with MS or SRS. METHODS The records of 399 VS patients who were cared for by 2 neurosurgeons and 1 neurotologist between 2001 and 2014 were evaluated. From this data set, 3 retrospective matched cohorts were created to compare hearing preservation (21 matched pairs), facial nerve preservation (83 matched pairs), intervention-free survival, and complication rates (85 matched pairs) between cases managed with SRS and patients managed with MS. Cases were matched for age at surgery (± 10 years) and lesion size (± 0.1 cm). To compare hearing outcomes, cases were additionally matched for preoperative Class A hearing according to the American Academy of Otolaryngology-Head and Neck Surgery guidelines. To compare facial nerve (i.e., cranial nerve [CN] VII) outcomes, cases were additionally matched for preoperative House-Brackmann (HB) score. Investigators who were not involved with patient care reviewed the clinical and imaging records. The reported outcomes were as assessed at the time of the last follow-up, unless otherwise stated. RESULTS The preservation of preoperative Class A hearing status was achieved in 14.3% of MS cases compared with 42.9% of SRS cases (OR 4.5; p < 0.05) after an average follow-up interval of 43.7 months and 30.3 months, respectively. Serviceable hearing was preserved in 42.8% of MS cases compared with 85.7% of SRS cases (OR 8.0; p < 0.01). The rates of postoperative CN VII dysfunction were low for both groups, although significantly higher in the MS group (HB III-IV 11% vs 0% for SRS; OR 21.3; p < 0.01) at a median follow-up interval of 35.7 and 19.0 months for MS and SRS

  19. Distributed simulation of long-term hydrological processes in a medium-sized periurban catchment under changing land use and rainwater management.

    NASA Astrophysics Data System (ADS)

    Labbas, Mériem; Braud, Isabelle; Branger, Flora; Kralisch, Sven

    2013-04-01

    Growing urbanization and related anthropogenic processes have a high potential to influence hydrological process dynamics. Typical consequences are an increase of surface imperviousness and modifications of water flow paths due to artificial channels and barriers (combined and separated system, sewer overflow device, roads, ditches, etc.). Periurban catchments, at the edge of large cities, are especially affected by fast anthropogenic modifications. They usually consist of a combination of natural areas, rural areas with dispersed settlements and urban areas mostly covered by built zones and spots of natural surfaces. In the context of the European Water Framework Directive (2000) and the Floods Directive (2007), integrated and sustainable solutions are needed to reduce flooding risks and river pollution at the scale of urban conglomerations or whole catchments. Their thorough management requires models able to assess the vulnerability of the territory and to compare the impact of different rainwater management options and planning issues. To address this question, we propose a methodology based on a multi-scale distributed hydrological modelling approach. It aims at quantifying the impact of ongoing urbanization and stormwater management on the long-term hydrological cycle in medium-sized periurban watershed. This method focuses on the understanding and formalization of dominant periurban hydrological processes from small scales (few ha to few km2) to larger scales (few hundred km2). The main objectives are to 1) simulate both urban and rural hydrological processes and 2) test the effects of different long-term land use and water management scenarios. The method relies on several tools and data: a distributed hydrological model adapted to the characteristics of periurban areas, land use and land cover maps from different dates (past, present, future) and information about rainwater management collected from local authorities. For the application of the method, the

  20. ChAT and NOS in human myenteric neurons: co-existence and co-absence.

    PubMed

    Beck, Martin; Schlabrakowski, Anne; Schrödl, Falk; Neuhuber, Winfried; Brehmer, Axel

    2009-10-01

    Most myenteric neurons contain one of the two generating enzymes for major excitatory and inhibitory neurotransmitters: choline acetyltransferase (ChAT) or neuronal nitric oxide synthase (NOS). Two minor groups of myenteric neurons contain either both enzymes or neither. Our study had two aims: (1) to compare the proportions of neurons stained for ChAT and/or NOS in human small and large intestinal whole-mounts by co-staining with an antibody against the human neuronal protein Hu C/D (HU); (2) to characterize these neurons morphologically by co-staining with a neurofilament (NF) antibody. In small intestinal whole-mounts co-stained with HU, we counted more ChAT-positive (ChAT+) than NOS+ neurons (52% vs. 38%), whereas the large intestine exhibited fewer ChAT+ than NOS+ neurons (38% vs. 50%). Neurons co-reactive for both ChAT and NOS accounted for about 3% in both regions, whereas neurons negative for both enzymes accounted for 7% in the small intestine and 8% in the large intestine. Co-staining with NF revealed that, in both small and large intestine, ChAT+/NOS+ neurons were either spiny (type I) neurons or displayed smaller perikarya that were weakly or not NF-stained. Of all spiny neurons, almost one third was co-reactive for ChAT and NOS, whereas nearly two thirds were positive only for NOS. Neurons negative for both ChAT and NOS were heterogeneous in size and NF reactivity. Thus, neither the co-existence nor the co-absence of ChAT and NOS in human myenteric neurons is indicative for particular neuron types, with several qualitative and quantitative parameters showing a wide range of interindividual variability.

  1. Cardiorespiratory ontogeny and response to environmental hypoxia of larval spiny lobster, Sagmariasus verreauxi.

    PubMed

    Fitzgibbon, Quinn P; Ruff, Nicole; Battaglene, Stephen C

    2015-06-01

    Cardiorespiratory function is vital to an organism's ability to respond to environmental stress and analysis of cardiorespiratory capacity of species or life stages can elucidate vulnerability to climate change. Spiny lobsters have one of the most complex pelagic larval life cycles of any invertebrate and recently there has been an unexplained decline in post-larval recruitment for a number of species. We conducted the first analysis of the larval ontogeny of oxygen consumption, heart rate, maxilla 2 ventilation rate and oxyregulatory capacity of the spiny lobster, Sagmariasus verreauxi, to gain insight into their vulnerability to ocean change and to investigate life stage specific sensitivity to temperature-dependent oxygen limitation. In normoxia, heart and maxilla 2 ventilation rates increased in early larval development before declining, which we hypothesise is related to the transition from myogenic to neurogenic cardiac control. Maxilla 2 ventilation rate was sensitive to hypoxia at all larval stages, while heart rate was only sensitive to hypoxia in the late phyllosoma stages. Oxygen consumption conformed to environmental hypoxia at all larval stages. Spiny lobster larvae have limited respiratory control due to immature gas exchange physiology, compounded by their exceptionally large size. The lack of oxyregulatory ability suggests that all development stages are vulnerable to changes in sea temperature and oxygen availability. The synergetic stressors of increased temperature and reduced dissolved oxygen in the marine environment will diminish spiny lobster larval performance, increasing the challenge to achieve their extended larval life cycle, which may contribute to declines in post-larval recruitment.

  2. Genetic isolation between the Western and Eastern Pacific populations of pronghorn spiny lobster Panulirus penicillatus.

    PubMed

    Chow, Seinen; Jeffs, Andrew; Miyake, Yoichi; Konishi, Kooichi; Okazaki, Makoto; Suzuki, Nobuaki; Abdullah, Muhamad F; Imai, Hideyuki; Wakabayasi, Toshie; Sakai, Mitsuo

    2011-01-01

    The pronghorn spiny lobster, Panulirus penicillatus, is a circumtropical species which has the widest global distribution among all the species of spiny lobster, ranging throughout the entire Indo-Pacific region. Partial nucleotide sequences of mitochondrial DNA COI (1,142-1,207 bp) and 16S rDNA (535-546 bp) regions were determined for adult and phyllosoma larval samples collected from the Eastern Pacific (EP)(Galápagos Islands and its adjacent water), Central Pacific (CP)(Hawaii and Tuamotu) and the Western Pacific (WP)(Japan, Indonesia, Fiji, New Caledonia and Australia). Phylogenetic analyses revealed two distinct large clades corresponding to the geographic origin of samples (EP and CP+WP). No haplotype was shared between the two regional samples, and average nucleotide sequence divergence (Kimura's two parameter distance) between EP and CP+WP samples was 3.8±0.5% for COI and 1.0±0.4% for 16S rDNA, both of which were much larger than those within samples. The present results indicate that the Pacific population of the pronghorn spiny lobster is subdivided into two distinct populations (Eastern Pacific and Central to Western Pacific), with no gene flow between them. Although the pronghorn spiny lobster have long-lived teleplanic larvae, the vast expanse of Pacific Ocean with no islands and no shallow substrate which is known as the East Pacific Barrier appears to have isolated these two populations for a long time (c.a. 1MY).

  3. 75 FR 16716 - Fisheries of the Northeastern United States; Proposed 2010 Specifications for the Spiny Dogfish...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-04-02

    ... Assessment (EA) and Regulatory Impact Review (RIR)/Initial Regulatory Flexibility Analysis (IRFA), are... (NEFSC) updated the spiny dogfish stock status using the population modeling approach from the 43rd Stock.... In addition, the current survival rate of pups may be lower than historic levels due to...

  4. 76 FR 14644 - Fisheries of the Northeastern United States; Proposed 2011 Specifications for the Spiny Dogfish...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-03-17

    ... over the long term. Authority: 16 U.S.C. 1801 et seq. Dated: March 11, 2011. Samuel D. Rauch III... overfished by NMFS on April 3, 1998, and added to the list of overfished stocks in the Report on the Status... required NMFS to prepare measures to end overfishing and rebuild the spiny dogfish stock. During 1998...

  5. Neocortical neuronal morphology in the Siberian Tiger (Panthera tigris altaica) and the clouded leopard (Neofelis nebulosa).

    PubMed

    Johnson, Cameron B; Schall, Matthew; Tennison, Mackenzie E; Garcia, Madeleine E; Shea-Shumsky, Noah B; Raghanti, Mary Ann; Lewandowski, Albert H; Bertelsen, Mads F; Waller, Leona C; Walsh, Timothy; Roberts, John F; Hof, Patrick R; Sherwood, Chet C; Manger, Paul R; Jacobs, Bob

    2016-12-01

    Despite extensive investigations of the neocortex in the domestic cat, little is known about neuronal morphology in larger felids. To this end, the present study characterized and quantified the somatodendritic morphology of neocortical neurons in prefrontal, motor, and visual cortices of the Siberian tiger (Panthera tigris altaica) and clouded leopard (Neofelis nebulosa). After neurons were stained with a modified Golgi technique (N = 194), dendritic branching and spine distributions were analyzed using computer-assisted morphometry. Qualitatively, aspiny and spiny neurons in both species appeared morphologically similar to those observed in the domestic cat. Although the morphology of spiny neurons was diverse, with the presence of extraverted, inverted, horizontal, and multiapical pyramidal neurons, the most common variant was the typical pyramidal neuron. Gigantopyramidal neurons in the motor cortex were extremely large, confirming the observation of Brodmann ([1909] Vergleichende Lokalisationlehre der Grosshirnrinde in ihren Prinzipien dargestellt auf Grund des Zellenbaues. Leipzig, Germany: J.A. Barth), who found large somata for these neurons in carnivores in general, and felids in particular. Quantitatively, a MARSplines analysis of dendritic measures differentiated typical pyramidal neurons between the Siberian tiger and the clouded leopard with 93% accuracy. In general, the dendrites of typical pyramidal neurons were more complex in the tiger than in the leopards. Moreover, dendritic measures in tiger pyramidal neurons were disproportionally large relative to body/brain size insofar as they were nearly as extensive as those observed in much larger mammals (e.g., African elephant). Comparison of neuronal morphology in a more diverse collection of larger felids may elucidate the comparative context for the relatively large size of the pyramidal neurons observed in the present study. J. Comp. Neurol. 524:3641-3665, 2016. © 2016 Wiley Periodicals, Inc.

  6. The Biology and Husbandry of the African Spiny Mouse (Acomys cahirinus) and the Research Uses of a Laboratory Colony.

    PubMed

    Haughton, Cheryl L; Gawriluk, Thomas R; Seifert, Ashley W

    2016-01-01

    African spiny mice (Acomys spp.) are unique precocial rodents that are found in Africa, the Middle East, and southern Asia. They exhibit several interesting life-history characteristics, including precocial development, communal breeding, and a suite of physiologic adaptations to desert life. In addition to these characteristics, African spiny mice are emerging as an important animal model for tissue regeneration research. Furthermore, their important phylogenetic position among murid rodents makes them an interesting model for evolution and development studies. Here we outline the necessary components for maintaining a successful captive breeding colony, including laboratory housing, husbandry, and health monitoring aspects. We also review past and present studies focused on spiny mouse behavior, reproduction, and disease. Last, we briefly summarize various current biomedical research directions using captive-bred spiny mice.

  7. The Biology and Husbandry of the African Spiny Mouse (Acomys cahirinus)and the Research Uses of a Laboratory Colony

    PubMed Central

    Haughton, Cheryl L; Gawriluk, Thomas R; Seifert, Ashley W

    2016-01-01

    African spiny mice (Acomysspp.) are unique precocial rodents that are found in Africa, the Middle East, and southern Asia. They exhibit several interesting life-history characteristics, including precocial development, communal breeding, and a suite of physiologic adaptations to desert life. In addition to these characteristics, African spiny mice are emerging as an important animal model for tissue regeneration research. Furthermore, their important phylogenetic position among murid rodents makes them an interesting model for evolution and development studies. Here we outline the necessary components for maintaining a successful captive breeding colony, including laboratory housing, husbandry, and health monitoring aspects. We also review past and present studies focused on spiny mouse behavior, reproduction, and disease. Last, we briefly summarize various current biomedical research directions using captive-bred spiny mice. PMID:26817973

  8. 77 FR 76458 - Fisheries of the Caribbean, Gulf of Mexico, and South Atlantic; Spiny Lobster Fishery of Puerto...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-12-28

    ... spiny lobster before releasing the lobster with minimal harm. Data will be collected and analyzed to... returned to the water with a minimum of harm. This EFP, if granted, would also authorize the collection...

  9. Behavioral plasticity of a grass-feeding caterpillar in response to spiny- or smooth-edged leaf blades

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Ontogenetic changes in feeding behavior of armyworms, Pseudaletia unipucta (Haworth), were compared on tall fescue [Schedonorus arundinaceus (Schreb.) Dumort] cultivars with spiny-, intermediate-, or smoothedged leaf blades to clarify whether the edge spines deter caterpillars, in which case release...

  10. [Classification of neurons in the visual cortex of the guinea pig (Cavia porcellus). A combined Golgi-Nissl study using deimpregnation technics].

    PubMed

    Werner, L; Hedlich, A; Koglin, A

    1986-01-01

    The aim of the investigation is the identification of neuronal types in the visual cortex of the guinea pig (Cavia porcellus) in Nissl preparations. In two rapid Golgi series (modified by Fairén et al. 1977) and nine Golgi-Kopsch series eleven neuronal types could be classified: 1. Neurons with long axonal main stems: Pyramidal cells (layers II-VI), pyramid-like cells (layers I, VI), spiny stellate cells (layer IV). 2. Neurons with locally distributed axons: large and small aspiny cells (layers II-VI), neuroglioform cells (layers I-VI), large sparsely spiny cells with ascending axons (Martinotti cells) (layers III-VI), small sparsely spiny cells with variable axons (layer IV), bipolar cells (layers II-VI), chandelier cells (layers II, III), double bouquet cells (layers II, III), and 3. a horizontal cell in layer I without an impregnated axon. To identify Nissl stained somata, Golgi impregnated neurons were deimpregnated. Now cytoplasmic and nuclear features can be compared. In order to get a survey about the variability of the somal features, we have deimpregnated 245 neurons on the whole using either gold chloride (Fairén et al. 1977) combined with the rapid Golgi method, modified by Fairén et al. (1977), or a diluted solution of ammonia (Braak and Braak 1982) combined with the Golgi-Kopsch method, nonembedded, in glycerol stored material and in celloidin embedded sections, resp. After deimpregnation several neuronal classes could be distinguished considering at first the width of the cytoplasm and the localization of the nucleus. There are Nissl stained somata with corresponding features: 1. Pyramidal cells, pyramid-like cells, and spiny stellate cells of the layer IV with relatively broad cytoplasm and bright, centrally localized nuclei. 2. Large aspiny cells which vary in somal sizes and shapes with very broad cytoplasm and bright, centrally or excentrally localized nuclei. 3. Small aspiny cells, some of the neuroglioform cells, and small sparsely spiny

  11. Neocortical neuronal morphology in the newborn giraffe (Giraffa camelopardalis tippelskirchi) and African elephant (Loxodonta africana).

    PubMed

    Jacobs, Bob; Lee, Laura; Schall, Matthew; Raghanti, Mary Ann; Lewandowski, Albert H; Kottwitz, Jack J; Roberts, John F; Hof, Patrick R; Sherwood, Chet C

    2016-02-01

    Although neocortical neuronal morphology has been documented in the adult giraffe (Giraffa camelopardalis tippelskirchi) and African elephant (Loxodonta africana), no research has explored the cortical architecture in newborns of these species. To this end, the current study examined the morphology of neurons from several cortical areas in the newborn giraffe and elephant. After cortical neurons were stained with a modified Golgi technique (N = 153), dendritic branching and spine distributions were analyzed by using computer-assisted morphometry. The results showed that newborn elephant neurons were considerably larger in terms of all dendritic and spine measures than newborn giraffe neurons. Qualitatively, neurons in the newborns appeared morphologically comparable to those in their adult counterparts. Neurons in the newborn elephant differed considerably from those observed in other placental mammals, including the giraffe, particularly with regard to the morphology of spiny projection neurons. Projection neurons were observed in both species, with a much larger variety in the elephant (e.g., flattened pyramidal, nonpyramidal multipolar, and inverted pyramidal neurons). Although local circuit neurons (i.e., interneurons, neurogliaform, Cajal-Retzius neurons) resembled those observed in other eutherian mammals, these were usually spiny, which contrasts with their adult, aspiny equivalents. Newborn projection neurons were smaller than the adult equivalents in both species, but newborn interneurons were approximately the same size as their adult counterparts. Cortical neuromorphology in the newborn giraffe is thus generally consistent with what has been observed in other cetartiodactyls, whereas newborn and adult elephant morphology appears to deviate substantially from what is commonly observed in other placental mammals.

  12. An Intact Retroviral Gene Conserved in Spiny-Rayed Fishes for over 100 My.

    PubMed

    Henzy, Jamie E; Gifford, Robert J; Kenaley, Christopher P; Johnson, Welkin E

    2016-12-30

    We have identified a retroviral envelope gene with a complete, intact open reading frame (ORF) in 20 species of spiny-rayed fishes (Acanthomorpha). The taxonomic distribution of the gene, "percomORF", indicates insertion into the ancestral lineage >110 Ma, making it the oldest known conserved gene of viral origin in a vertebrate genome. Underscoring its ancient provenence, percomORF exists as an isolated ORF within the intron of a widely conserved host gene, with no discernible proviral sequence nearby. Despite its remarkable age, percomORF retains canonical features of a retroviral glycoprotein, and tests for selection strongly suggest cooption for a host function. Retroviral envelope genes have been coopted for a role in placentogenesis by numerous lineages of mammals, including eutherians and marsupials, representing a variety of placental structures. Therefore percomORF's presence within the group Percomorpha-unique among spiny-finned fishes in having evolved placentation and live birth-is especially intriguing.

  13. Locomotor activity in common spiny mice (Acomys cahirinuse): The effect of light and environmental complexity

    PubMed Central

    Eilam, David

    2004-01-01

    Background Rodents typically avoid illuminated and open areas, favoring dark or sheltered environments for activity. While previous studies focused on the effect of these environmental attributes on the level of activity, the present study tested whether the spatio-temporal structure of activity was also modified in illuminated compared with dark and complex compared with open arenas. For this, we tested common spiny mice (Acomys cahirinus) in empty or stone-containing arenas with lights on or lights off. Results In an illuminated or open arena, spiny mice moved in less frequent but longer trips with relatively long distances between consecutive stops. In contrast, in either a dark arena or an arena with stones, the animals took shorter and more frequent trips, with more stops per trip and shorter inter-stop distances. In illuminated arenas spiny mice remained mainly along the walls, whereas locomotion in the center was more prevalent in dark empty arenas, and was carried out along convoluted paths. Increasing environmental complexity by adding stones to either illuminated or dark arenas increased locomotion along straight trajectories and away from walls. Conclusions Earlier findings of reduced activity in illuminated or open areas have been extended in the present study by demonstrating changes in the spatio-temporal structure of locomotor behavior. In the more complex arenas (with stones) spiny mice traveled along short straight segments whereas in the open their trips were longer and took the shape of a zigzag path which is more effective against fast or nearby predators. Alternatively, the zigzag path may reflect a difficulty in navigation. PMID:15537426

  14. Copper toxicity in the spiny dogfish (Squalus acanthias): urea loss contributes to the osmoregulatory disturbance.

    PubMed

    De Boeck, G; Hattink, J; Franklin, N M; Bucking, C P; Wood, S; Walsh, P J; Wood, C M

    2007-08-30

    Previous research showed that the spiny dogfish, Squalus acanthias, is much more sensitive to silver exposure than typical marine teleosts. The aim of the present study was to investigate if spiny dogfish were equally sensitive to copper exposure and whether the toxic mechanisms were the same. We exposed cannulated and non-cannulated spiny dogfish to measured concentrations of Cu (nominally 0, 500, 1000 and 1500 microg L(-1) Cu) for 72-96 h. All Cu exposures induced acidosis and lactate accumulation of either a temporary (500 microg L(-1)) or more persistent nature (1000 and 1500 microg L(-1)). At the two highest Cu concentrations, gill Na(+)/K(+)-ATPase activities were reduced by 45% (1000 microg L(-1)) and 62% (1500 microg L(-1)), and plasma Na(+) and Cl(-) concentrations increased by approximately 50 mM each. At the same time urea excretion doubled and plasma urea dropped by approximately 100 mM. Together with plasma urea, plasma TMAO levels dropped proportionally, indicating that the general impermeability of the gills was compromised. Overall plasma osmolarity did not change. Cu accumulation was limited with significant increases in plasma Cu and elevated gill and kidney Cu burdens at 1000 and 1500 microg L(-1). We conclude that Cu, like Ag, exerts toxic effect on Na(+)/K(+)-ATPase activities in the shark similar to those of teleosts, but there is an additional toxic action on elasmobranch urea retention capacities. With a 96 h LC(50) in the 800-1000 microg L(-1) range, overall sensitivity of spiny dogfish for Cu is, in contrast with its sensitivity to Ag, only slightly lower than in typical marine teleosts.

  15. Genetic Isolation between the Western and Eastern Pacific Populations of Pronghorn Spiny Lobster Panulirus penicillatus

    PubMed Central

    Chow, Seinen; Jeffs, Andrew; Miyake, Yoichi; Konishi, Kooichi; Okazaki, Makoto; Suzuki, Nobuaki; Abdullah, Muhamad F.; Imai, Hideyuki; Wakabayasi, Toshie; Sakai, Mitsuo

    2011-01-01

    The pronghorn spiny lobster, Panulirus penicillatus, is a circumtropical species which has the widest global distribution among all the species of spiny lobster, ranging throughout the entire Indo-Pacific region. Partial nucleotide sequences of mitochondrial DNA COI (1,142–1,207 bp) and 16S rDNA (535–546 bp) regions were determined for adult and phyllosoma larval samples collected from the Eastern Pacific (EP)(Galápagos Islands and its adjacent water), Central Pacific (CP)(Hawaii and Tuamotu) and the Western Pacific (WP)(Japan, Indonesia, Fiji, New Caledonia and Australia). Phylogenetic analyses revealed two distinct large clades corresponding to the geographic origin of samples (EP and CP+WP). No haplotype was shared between the two regional samples, and average nucleotide sequence divergence (Kimura's two parameter distance) between EP and CP+WP samples was 3.8±0.5% for COI and 1.0±0.4% for 16S rDNA, both of which were much larger than those within samples. The present results indicate that the Pacific population of the pronghorn spiny lobster is subdivided into two distinct populations (Eastern Pacific and Central to Western Pacific), with no gene flow between them. Although the pronghorn spiny lobster have long-lived teleplanic larvae, the vast expanse of Pacific Ocean with no islands and no shallow substrate which is known as the East Pacific Barrier appears to have isolated these two populations for a long time (c.a. 1MY). PMID:22195038

  16. Channel noise is essential for perithreshold oscillations in entorhinal stellate neurons.

    PubMed

    Dorval, Alan D; White, John A

    2005-10-26

    Previous experimental and computational work (for review, see White et al., 2000) has suggested that channel noise, generated by the stochastic flicker of voltage-gated ion channels, can be a major contributor to electrical membrane noise in neurons. In spiny stellate neurons of the entorhinal cortex, we remove the primary source of channel noise by pharmacologically blocking the native persistent Na+ conductance. Via the dynamic-clamp technique (Robinson and Kawai, 1993; Sharp et al., 1993), we then introduce virtual persistent Na+ channels into the membranes of the stellate neurons. By altering the mathematical properties of these virtual "knock-ins," we demonstrate that stochastic flicker of persistent Na+ channels is necessary for the existence of slow perithreshold oscillations that characterize stellate neurons. Channel noise also alters the ability of stellate neurons to phase lock to weak sinusoidal stimuli. These results provide the first direct demonstration that physiological levels of channel noise can produce qualitative changes in the integrative properties of neurons.

  17. High-content screening data management for drug discovery in a small- to medium-size laboratory: results of a collaborative pilot study focused on user expectations as indicators of effectiveness.

    PubMed

    Berlinicke, Cynthia A; Ackermann, Christopher F; Chen, Steve H; Schulze, Christoph; Shafranovich, Yakov; Myneni, Sahiti; Patel, Vimla L; Wang, Jian; Zack, Donald J; Lindvall, Mikael; Bova, G Steven

    2012-08-01

    High-content screening (HCS) technology provides a powerful vantage point to approach biological problems; it allows analysis of cell parameters, including changes in cell or protein movement, shape, or texture. As part of a collaborative pilot research project to improve bioscience research data integration, we identified HCS data management as an area ripe for advancement. A primary goal was to develop an integrated data management and analysis system suitable for small- to medium-size HCS programs that would improve research productivity and increase work satisfaction. A system was developed that uses Labmatrix, a Web-based research data management platform, to integrate and query data derived from a Cellomics STORE database. Focusing on user expectations, several barriers to HCS productivity were identified and reduced or eliminated. The impact of the project on HCS research productivity was tested through a series of 18 lab-requested integrated data queries, 7 of which were fully enabled, 7 partially enabled, and 4 enabled through data export to standalone data analysis tools. The results are limited to one laboratory, but this pilot suggests that through an "implementation research" approach, a network of small- to medium-size laboratories involved in HCS projects could achieve greater productivity and satisfaction in drug discovery research.

  18. Intense Pulsed Light Alone and in Combination with Erbium Yttrium-Aluminum-Garnet Laser on Small-to-Medium Sized Congenital Melanocytic Nevi: Single Center Experience Based on Retrospective Chart Review

    PubMed Central

    Lee, Mi So; Jun, Hee Jin; Cho, Sang Hyun; Lee, Jeong Deuk

    2017-01-01

    Background Treatment of congenital melanocytic nevi (CMN) with intense pulsed light (IPL) has recently produced promising results. Objective To evaluate the clinical and histological outcomes of small-to-medium sized CMN treated with IPL alone and in combination with erbium: yttrium-aluminum-garnet (Er: YAG) laser. Methods We performed a retrospective chart review of 26 small-to-medium sized CMN treated as described above. The reduction in visible pigmentation, signs of recurrence and any adverse skin changes were evaluated by two independent clinicians. Results Seventeen patients completed treatment and were followed-up. Nine were not able to complete treatment due to work, change in residence, and treatment related stress. Ten patients received IPL alone (mean: 10.5 sessions) and 7 underwent treatment with IPL (mean: 7.7 sessions) and Er: YAG/IPL combination therapy (mean: 4.7 sessions). The initial treatment outcome was cleared in 5 patients and excellent in 12. Fourteen patients (82.4%) showed CMN recurrence one year after treatment completion. The histological results from a patient with an excellent clinical outcome showed remnant nevus cells nests in the deep dermis. Conclusion IPL treatment alone and in combination with Er: YAG laser are not definitive treatments for CMN and should not be considered as first-line treatment. PMID:28223745

  19. Synchronous behavior of two coupled electronic neurons

    SciTech Connect

    Pinto, R. D.; Varona, P.; Volkovskii, A. R.; Szuecs, A.; Abarbanel, Henry D. I.; Rabinovich, M. I.

    2000-08-01

    We report on experimental studies of synchronization phenomena in a pair of analog electronic neurons (ENs). The ENs were designed to reproduce the observed membrane voltage oscillations of isolated biological neurons from the stomatogastric ganglion of the California spiny lobster Panulirus interruptus. The ENs are simple analog circuits which integrate four-dimensional differential equations representing fast and slow subcellular mechanisms that produce the characteristic regular/chaotic spiking-bursting behavior of these cells. In this paper we study their dynamical behavior as we couple them in the same configurations as we have done for their counterpart biological neurons. The interconnections we use for these neural oscillators are both direct electrical connections and excitatory and inhibitory chemical connections: each realized by analog circuitry and suggested by biological examples. We provide here quantitative evidence that the ENs and the biological neurons behave similarly when coupled in the same manner. They each display well defined bifurcations in their mutual synchronization and regularization. We report briefly on an experiment on coupled biological neurons and four-dimensional ENs, which provides further ground for testing the validity of our numerical and electronic models of individual neural behavior. Our experiments as a whole present interesting new examples of regularization and synchronization in coupled nonlinear oscillators. (c) 2000 The American Physical Society.

  20. Neuronal morphology in the African elephant (Loxodonta africana) neocortex.

    PubMed

    Jacobs, Bob; Lubs, Jessica; Hannan, Markus; Anderson, Kaeley; Butti, Camilla; Sherwood, Chet C; Hof, Patrick R; Manger, Paul R

    2011-01-01

    Virtually nothing is known about the morphology of cortical neurons in the elephant. To this end, the current study provides the first documentation of neuronal morphology in frontal and occipital regions of the African elephant (Loxodonta africana). Cortical tissue from the perfusion-fixed brains of two free-ranging African elephants was stained with a modified Golgi technique. Neurons of different types (N=75), with a focus on superficial (i.e., layers II-III) pyramidal neurons, were quantified on a computer-assisted microscopy system using Neurolucida software. Qualitatively, elephant neocortex exhibited large, complex spiny neurons, many of which differed in morphology/orientation from typical primate and rodent pyramidal neurons. Elephant cortex exhibited a V-shaped arrangement of bifurcating apical dendritic bundles. Quantitatively, the dendrites of superficial pyramidal neurons in elephant frontal cortex were more complex than in occipital cortex. In comparison to human supragranular pyramidal neurons, elephant superficial pyramidal neurons exhibited similar overall basilar dendritic length, but the dendritic segments tended to be longer in the elephant with less intricate branching. Finally, elephant aspiny interneurons appeared to be morphologically consistent with other eutherian mammals. The current results thus elaborate on the evolutionary roots of Afrotherian brain organization and highlight unique aspects of neural architecture in elephants.

  1. Morphology and ontogeny of rat perirhinal cortical neurons.

    PubMed

    Furtak, Sharon Christine; Moyer, James Russell; Brown, Thomas Huntington

    2007-12-10

    Golgi-impregnated neurons from rat perirhinal cortex (PR) were classified into one of 15 distinct morphological categories (N = 6,891). The frequency of neurons in each cell class was determined as a function of the layer of PR and the age of the animal, which ranged from postnatal day 0 (P0) to young adulthood (P45). The developmental appearance of Golgi-impregnated neurons conformed to the expected "inside-out" pattern of development, meaning that cells populated in deep before superficial layers of PR. The relative frequencies of different cell types changed during the first 2 weeks of postnatal development. The largest cells, which were pyramidal and spiny multipolar neurons, appeared earliest. Aspiny stellate neurons were the last to appear. The total number of Golgi-impregnated neurons peaked at P10-12, corresponding to the time of eye-opening. This early increase in the number of impregnated neurons parallels observations in other cortical areas. The relative frequency of the 15 cell types remained constant between P14 to P45. The proportion of pyramidal neurons in PR ( approximately 50%) was much smaller than is typical of neocortex ( approximately 70%). A correspondingly larger proportion of PR neurons were nonpyramidal cells that are less common in neocortex. The relative frequency distribution of cell types creates an overall impression of considerable morphological diversity, which is arguably related to the particular manner in which this periallocortical brain region processes and stores information.

  2. The types of neurons in the claustrum of bison bonasus: Nissl and Golgi study.

    PubMed

    Równiak, M; Szteyn, S; Robak, A; Klawon, M

    1994-01-01

    The Nissl staining and Golgi impregnation methods has been used to characterize the types of neurons in the claustrum of bison bonasus. Two fairly divergent subpopulations of cells can be distinguished by means of Golgi preparation technique. The first group--comprising the bulk of claustral neurons--is composed of only one type of large, efferent nerve cells with long axons and dendrites covered with spines. The somata and initial portion of dendritic processes are devoid of spines. The second group consists of large and medium-size interneurons with smooth infrequently branching dendrites. Amongst them two sub-populations can be observed: with dendritic swellings and with dendrites deveoid of them. In Nissl stained sections the claustral neuronal population consists of large multipolar cells among which fewer large or medium-size, spindle-shaped cells are dispersed. The multipolar cells and also spindle-shaped neurons contain widely distributed, deeply-stained, medium-sized pigment granules. No orderly alignment of cells can be seen.

  3. The influence of dexamethasone administered prenatally on cartilage of newborn spiny mouse (Acomys cahirinus) offspring.

    PubMed

    Iwaniak, P; Dobrowolski, P; Tomaszewska, E; Hułas-Stasiak, M; Tomczyk, A; Gawron, A

    2015-11-17

    Considering the negative effects of glucocorticoid treatment, especially during fetal development it is important to investigate effectors decreasing such disadvantages. The aim of this study was to investigate the effect of prenatally administered dexamethasone (Dex), a synthetic glucocorticoid, on the histomorphometry of the femur in the offspring of spiny mice. The study was performed on 24 pregnant spiny mice. The time of the experiment included the prenatal period between the 20th day of gestation until birth (pregnancy lasts on average of 36-38 days). The mice from the experimental group received dexamethasone per os in a dose of 125 mg/kg birth weight daily. At the end, the newborns from the experimental and control group were weighted and euthanized. Maternal Dex treatment resulted in a 17% decrease in birth weight in newborns. Dex administration significantly reduced the thickness of the hypertrophy zone of the growth plate by 34% and total thickness by 8,7%. In addition, Dex decreased the number of cells in the articular cartilage by 27% and significantly decreased their diameter by 5%. Dex also affected the structure and spatial distribution of thick and thin collagen fibers, lowering the proportion of thin fibers compared with the control group. Moreover, Dex treatment considerably lowered the amount of proteoglycans in articular and growth cartilages. Exposure to glucocorticoids in pregnant spiny mice affects cartilage development by accelerating maturity of collagen fibers and growth plate, presumably along with further disruption of longitudinal growth of long bones.

  4. Caribbean Spiny Lobster Fishery Is Underpinned by Trophic Subsidies from Chemosynthetic Primary Production.

    PubMed

    Higgs, Nicholas D; Newton, Jason; Attrill, Martin J

    2016-12-19

    The Caribbean spiny lobster, Panulirus argus, is one of the most valuable fisheries commodities in the Central American region, directly employing 50,000 people and generating >US$450 million per year [1]. This industry is particularly important to small island states such as The Bahamas, which exports more lobster than any other country in the region [1]. Several factors contribute to this disproportionally high productivity, principally the extensive shallow-water banks covered in seagrass meadows [2], where fishermen deploy artificial shelters for the lobsters to supplement scarce reef habitat [3]. The surrounding seabed communities are dominated by lucinid bivalve mollusks that live among the seagrass root system [4, 5]. These clams host chemoautotrophic bacterial symbionts in their gills that synthesize organic matter using reduced sulfur compounds, providing nutrition to their hosts [6]. Recent studies have highlighted the important role of the lucinid clam symbiosis in maintaining the health and productivity of seagrass ecosystems [7, 8], but their biomass also represents a potentially abundant, but as yet unquantified, food source to benthic predators [9]. Here we undertake the first analysis of Caribbean spiny lobster diet using a stable isotope approach (carbon, nitrogen, and sulfur) and show that a significant portion of their food (∼20% on average) is obtained from chemosynthetic primary production in the form of lucinid clams. This nutritional pathway was previously unrecognized in the spiny lobster's diet, and these results are the first empirical evidence that chemosynthetic primary production contributes to the productivity of commercial fisheries stocks.

  5. Isolation, characterization, and multiplexing of novel microsatellite markers for the tropical scalloped spiny lobster (Panulirus homarus).

    PubMed

    Delghandi, M; Goddard, S; Jerry, D R; Dao, H T; Afzal, H; Al-Jardani, S S

    2015-12-29

    Of the various spiny lobster species in the tropical and subtropical Indo-West Pacific region, the tropical scalloped spiny lobster (Panulirus homarus) supports one of the most commercially valuable fishery resources in many coastal African and Asian countries. The last decade has witnessed a serious decline in the wild populations of this species. Knowledge of the genetic basis of spiny lobster population structure is a prerequisite to achieve a sustainable fisheries management for this species. Here, we describe 13 novel polymorphic microsatellite markers developed for P. homarus, using a cross-species primer design strategy based on P. ornatus Roche 454 shot-gun generated sequencing. Microsatellite polymorphisms were assessed in 96 unrelated P. homarus individuals of a natural population, with the number of alleles per locus varying from 2 to 14, the observed and expected heterozygosity from 0.00 to 0.78 and from 0.03 to 0.79, respectively, and with only four loci (Pho-G27, Pho-G32, Pho-G36, and Pho-G58) deviating from Hardy- Weinberg equilibrium. Genetic linkage disequilibrium analysis between all pairs of the loci showed significant departure from the null hypothesis between loci Pho-G22 - Pho-G30, and Pho-G30 - Pho-G35. The successful cross amplification of these microsatellites highlights the potential of the developed microsatellites for future population genetic research within the different Panulirus species.

  6. Maternal-fetal communication of circadian phase in a precocious rodent, the spiny mouse

    SciTech Connect

    Weaver, D.R.; Reppert, S.M. )

    1987-10-01

    The development of circadian rhythms was examined in a precocious rodent species, the spiny mouse. Spiny mouse pups born and reared in constant darkness expressed robust circadian rhythms in locomotor activity as early as day 5 of live. Free-running activity rhythms of pups born and reared in constant darkness were coordinated with the dam on the day of birth. Postnatal maternal influences on pup rhythmicity are minimal in this species, as pups fostered on the day of birth to dams whose circadian phases were opposite to the pups' original dams were coordinated with their original dams on the day of birth. Studies using 2-deoxy-D-(1-{sup 14}C)-glucose authoradiography showed that there were synchronous (coordinated) rhythms in metabolic activity in the maternal and fetal suprachiasmatic nuclei, directly demonstrating prenatal coordination of maternal and fetal rhythmicity. Maternal-fetal coordination of circadian phase was not the result of direct entrainment of the fetuses to the environmental light-dark cycle. These results demonstrate that there is prenatal communication of circadian phase in this precocious species, without demonstrable postnatal maternal influences on pup circadian rhythmicity. Spiny mice therefore represent an important animal model in which circadian rhythms in the postnatal period can be used to precisely assess prenatal influences on circadian phase.

  7. The neuronal structure of paramamillary nuclei in Bison bonasus: Nissl and Golgi pictures.

    PubMed

    Robak, A; Szteyn, S; Równiak, M

    1998-01-01

    The studies were carried out on the hypothalamus of bison bonasus aged 2 and 3 months. Sections were made by means of Bagiński's technique and Nissl and Klüver-Barrera methods. Four types of neurons were distinguished in the paramamillary nuclei: nucleus supramamillaris (Sm) and nucleus tuberomammillaris pars posterior (Tmp). Type I, small and medium-size, triangular or fusiform cells, which have 2-3 slender, poorly ramified dendrites; typical leptodendritic neurons. Type II, medium size neurons with quadrangular or spindle-shaped perikaryons. Most of them have 3-4 thick dendritic trunks with ramifying relatively long dendrites. These cells show stalked-appearance and possess different appendages sparsely distributed. Type III is similar to type II, but is made of medium-size to large multipolar cells having quadrangular, triangular or fusiform perikaryons and relatively short dendrites. Type IV, small and medium-size, globular cells with 2 or 3 dendritic trunks, which dichotomously subdivide into quaternary dendrites. In all types of neurons, axons emerge from the perikaryon or initial portion of a dendritic trunk. Type I was found in both studied nuclei. Types II and III constitute mainly the nucleus tuberomamillaris pars posterior. Type IV preponderate in the nucleus supramamillaris. The characteristic feature of Tmp cells, in Nissl picture was irregular contour of their somas and clumps of rough Nisls granules, which appear to lie outside the perikaryons. In Sm there were also lightly stained small rounded cells having both small amount of the cytoplasm and tigroid matter.

  8. Medium- to long-term results of a randomized controlled trial to assess the efficacy of arthoscopic-subacromial decompression versus mini-open repair for the treatment of medium-sized rotator cuff tears

    PubMed Central

    Birch, Ann; Temperley, David; Odak, Saurabh; Walton, Michael J; Haines, John F; Trail, Ian

    2015-01-01

    Background We report on the medium- to long-term results of a randomized controlled trial (RCT) aiming to determine whether rotator cuff repair confers any advantage over arthroscopic sub-acromial decompression (ASAD) alone in the management of medium-sized rotator cuff tears. Methods Ethical approval was sought to follow-up patients previously enrolled in a completed and previously published RCT comparing the outcome of ASAD with mini-open cuff repair for the treatment of rotator cuff tear. Forty-two patients were enrolled in the original study, with a mean of 64 years (range 54 years to 77 years). Results Fifteen of the original 17 patients randomized to ASAD alone and 18 of the original 25 patients randomized to cuff repair were available for follow-up. Each patient underwent American Shoulder and Elbow Surgeons (ASES), Disabilities of the Arm, Shoulder and Hand (DASH) and Constant scoring, and clinical and ultrasound examination. Mean duration of follow-up was 7 years (range 5 years to 11 years). There was no statistically significant difference in terms of ASES, DASH and Constant scores at follow-up between the two groups. Some 33% of patients in the cuff-repair group had a proven re-rupture on ultrasound. This patient subgroup had significantly worse Constant scores compared to patients where the repair remained intact. None of the patients from either group developed cuff-tear arthropathy requiring arthroplasty surgery. Conclusions In this medium- to longer-term study, there is no demonstrable significant benefit of cuff repair over decompression alone for the treatment of medium-sized rotator cuff tears, in terms of ASES, DASH and Constant scores for pain, function and strength modules. The presence of cuff tear does not necessitate surgical repair. This conclusion should drive surgical strategies and shared decision-making between patients and surgeons. PMID:27583006

  9. Electrophysiological property and chemical sensitivity of primary afferent neurons that innervate rat whisker hair follicles

    PubMed Central

    Ikeda, Ryo

    2016-01-01

    Whisker hair follicles are sensory organs that sense touch and perform tactile discrimination in animals, and they are sites where sensory impulses are initiated when whisker hairs touch an object. The sensory signals are then conveyed by whisker afferent fibers to the brain for sensory perception. Electrophysiological property and chemical sensitivity of whisker afferent fibers, important factors affecting whisker sensory processing, are largely not known. In the present study, we performed patch-clamp recordings from pre-identified whisker afferent neurons in whole-mount trigeminal ganglion preparations and characterized their electrophysiological property and sensitivity to ATP, serotonin and glutamate. Of 97 whisker afferent neurons examined, 67% of them are found to be large-sized (diameter ≥45 µm) cells and 33% of them are medium- to small-sized (diameter <45 µm) cells. Almost every large-sized whisker afferent neuron fires a single action potential but many (40%) small/medium-sized whisker afferent neurons fire multiple action potentials in response to prolonged stepwise depolarization. Other electrophysiological properties including resting membrane potential, action potential threshold, and membrane input resistance are also significantly different between large-sized and small/medium-sized whisker afferent neurons. Most large-sized and many small/medium-sized whisker afferent neurons are sensitive to ATP and/or serotonin, and ATP and/or serotonin could evoke strong inward currents in these cells. In contrast, few whisker afferent neurons are sensitive to glutamate. Our results raise a possibility that ATP and/or serotonin may be chemical messengers involving sensory signaling for different types of rat whisker afferent fibers. PMID:27927797

  10. Species profiles: life histories and environmental requirements of coastal fishes and invertebrates (Pacific Southwest). Spiny lobster. [Panulirus interruptus

    SciTech Connect

    Shaw, W.N.

    1986-04-01

    The spiny lobster (Panulirus interruptus) supports a valuable commercial and sport fishery along the southern California coast. Mating takes place from March to August in water 50 to 100 ft deep. The larvae pass through 11 pelagic stages in 7 to 9 months. the puerulus stage lasts another 2.5 months before the lobster transforms into the benthic form. Age at sexual maturity is 3 to 6 years for males and 5 to 9 years for females. Spiny lobsters are caught incommercial traps from October through March. Sport fishing for lobsters is mainly done by skin divers and scuba divers. Juveniles live in shallow coastal waters under the protection of plant cover; adults live in crevices or dens. Larvae are plankton feeders and adults are omnivorous, primarily scavengers. Because of a scarcity of information on larval food requirements and the slow larval growth rate, profitable mariculture of the spiny lobster currently is not feasible.

  11. Active cortical innervation protects striatal neurons from slow degeneration in culture.

    PubMed

    Fishbein, Ianai; Segal, Menahem

    2011-03-01

    Spiny striatal GABAergic neurons receive most of their excitatory input from the neocortex. In culture, striatal neurons form inhibitory connections, but the lack of intrinsic excitatory afferents prevents the development of spontaneous network activity. Addition of cortical neurons to the striatal culture provides the necessary excitatory input to the striatal neurons, and in the presence of these neurons, striatal cultures do express spontaneous network activity. We have confirmed that cortical neurons provide excitatory drive to striatal neurons in culture using paired recording from cortical and striatal neurons. In the presence of tetrodotoxin (TTX), which blocks action potential discharges, the connections between cortical and striatal neurons are still formed, and in fact synaptic currents generated between them when TTX is removed are far larger than in control, undrugged cultures. Interestingly, the continuous presence of TTX in the co-culture caused striatal cell death. These observations indicate that the mere presence of cortical neurons is not sufficient to preserve striatal neurons in culture, but their synchronous activity, triggered by cortical excitatory synapses, is critical for the maintenance of viability of striatal neurons. These results have important implications for understanding the role of activity in neurodegenerative diseases of the striatum.

  12. From medium-sized to megawatt turbines...

    SciTech Connect

    Dongen, W. van

    1996-12-31

    One of the world`s first 500 kW turbines was installed in 1989 in the Netherlands. This forerunner of the current NedWind 500 kW range also represents the earliest predesign of the NedWind megawatt turbine. After the first 500 kW turbines with steel rotor blades and rotor diameter of 34 m, several design modifications followed, e.g. the rotor diameter was increased to 35 m and a tip brake was added. Later polyester blades were introduced and the rotor diameter was increased with 5 in. The drive train was also redesigned. Improvements on the 500 kW turbine concept has resulted in decreased cost, whereas annual energy output has increased to approx. 1.3 million kWh. Wind energy can substantially contribute to electricity supply. Maximum output in kiloWatthours is the target. Further improvement of the existing technology and implementation of flexible components may well prove to be a way to increase energy output, not only in medium or large sized wind turbines. 7 figs.

  13. Biological Warfare of the Spiny Plant Introducing Pathogenic Microorganisms into Herbivore's Tissues.

    PubMed

    Halpern, Malka; Waissler, Avivit; Dror, Adi; Lev-Yadun, Simcha

    2011-01-01

    Recently, it has been proposed that plants which have spines, thorns, and prickles use pathogenic aerobic and anaerobic bacteria, as well as pathogenic fungi, for defense against herbivores, especially vertebrates. Their sharp defensive appendages may inject various pathogenic agents into the body of the herbivores by piercing the outer defensive layer of the skin in a type of biological warfare. Here, we review data regarding the various bacterial taxa found on spines, as well as the medical literature regarding infections by bacteria and fungi related to spine injuries. We also present new evidence that, concerning the microbial flora, spines belonging to the palm tree Washingtonia filifera are probably a different habitat than the nondefensive green photosynthetic leaf surfaces. In addition, many plant species have microscopic internal and external spines (raphids and silica needles) which can also wound large herbivores as well as insects and other small invertebrate herbivores that usually attack in between large spines, prickles, and thorns. The large spines and sharp microscopic structures may inject not only the microorganisms that inhabit them into the herbivore's tissues, but also those preexisting on the skin surface or inside the digestive system of the herbivores and on the surface of nonspiny plant parts. A majority of the spiny plants visually advertise their spiny nature, a characteristic known as aposematism (warning coloration). The pathogenic microorganisms may sometimes be much more dangerous than the physical wounds inflicted by the spines. In accordance, we suggest that the possible cooperation or even just the random association of spines with pathogenic microorganisms contributed to the evolution of aposematism in spiny plants and animals. The role of these sharp defensive structures in inserting pathogenic viruses into the tissues of herbivores was never studied systematically and deserves special attention.

  14. The acoustic mechanics of stick slip friction in the California spiny lobster (Panulirus interruptus).

    PubMed

    Patek, S N; Baio, J E

    2007-10-01

    The dynamic interplay between static and sliding friction is fundamental to many animal movements. One interesting example of stick-slip friction is found in the sound-producing apparatus of many spiny lobster species (Palinuridae). The acoustic movements of the spiny lobster's plectrum over the file are generated by stick-slip friction between the two surfaces. We examined the microscopic anatomy, kinematics, acoustics and frictional properties of the California spiny lobster (Panulirus interruptus) toward the goal of quantitatively characterizing the frictional and acoustic mechanics of this system. Using synchronous high-speed video and sound recordings, we tested whether plectrum kinematics are correlated with acoustic signal features and found that plectrum velocity is positively correlated with acoustic amplitude. To characterize the frictional mechanics of the system, we measured frictional forces during sound production using excised plectrums and files. Similar to rubber materials sliding against hard surfaces, the static coefficient of friction in this system was on average 1.7. The change in the coefficient of friction across each stick-slip cycle varied substantially with an average change of 1.1. Although driven at a constant speed, the plectrum slipped at velocities that were positively correlated with the normal force between the two surfaces. Studies of friction in biological systems have focused primarily on adhesion and movement, while studies of stick-slip acoustics have remained under the purview of musical acoustics and engineering design. The present study offers an integrative analysis of an unusual bioacoustic mechanism and contrasts its physical parameters with other biological and engineered systems.

  15. Behavior patterns of cold-resistant golden spiny mouse Acomys russatus.

    PubMed

    Haim, A

    1991-09-01

    Nesting behavior and food storage were studied in a cold-resistant (CR) population of the golden spiny mouse, Acomys russatus, in Southern Sinai at an altitude of 1600 m. CR-mice, in contrast to cold-sensitive (CS) ones, built nests in which they stored food. Such mice were found to be winter-solitary. These results show that food supply is an essential parameter for the survival of CR-mice during winter. Therefore, it is suggested that food supply rather than energy conservation was the main driving force in the selection of a solitary behavior pattern of CR-mice.

  16. Ultrastructure of Kolmer's crystalloid in the pinealocytes of the common spiny mouse (Acomys cahirinus dimidiatus).

    PubMed

    Kappe, C

    1993-11-01

    Light- and electron-microscopical observations revealed a rod-like inclusion body in the pinealocytes of the common spiny mouse (Acomys cahirinus dimidiatus). Ultrastructurally, the body is composed of a varying number of tubes whose wall consists of thin filaments aligned in helical arrangement. The inner and outer surface of the wall is covered with ribosome-like granules. Based on a morphological analysis it is concluded that the body described in the present investigation is identical with Kolmer's crystalloid of horizontal cells in the human and primate retina.

  17. Large Intercalated Neurons of Amygdala Relay Noxious Sensory Information

    PubMed Central

    Bienvenu, Thomas C.M.; Busti, Daniela; Micklem, Benjamin R.; Mansouri, Mahnaz; Magill, Peter J.

    2015-01-01

    Various GABAergic neuron types of the amygdala cooperate to control principal cell firing during fear-related and other behaviors, and understanding their specialized roles is important. Among GABAergic neurons, the so-called intercalated cells (ITCcs) are critically involved in the expression and extinction of fear memory. Tightly clustered small-sized spiny neurons constitute the majority of ITCcs, but they are surrounded by sparse, larger neurons (L-ITCcs) for which very little information is known. We report here a detailed neurochemical, structural and physiological characterization of rat L-ITCcs, as identified with juxtacellular recording/labeling in vivo. We supplement these data with anatomical and neurochemical analyses of nonrecorded L-ITCcs. We demonstrate that L-ITCcs are GABAergic, and strongly express metabotropic glutamate receptor 1α and GABAA receptor α1 subunit, together with moderate levels of parvalbumin. Furthermore, L-ITCcs are innervated by fibers enriched with metabotropic glutamate receptors 7a and/or 8a. In contrast to small-sized spiny ITCcs, L-ITCcs possess thick, aspiny dendrites, have highly branched, long-range axonal projections, and innervate interneurons in the basolateral amygdaloid complex. The axons of L-ITCcs also project to distant brain areas, such as the perirhinal, entorhinal, and endopiriform cortices. In vivo recorded L-ITCcs are strongly activated by noxious stimuli, such as hindpaw pinches or electrical footshocks. Consistent with this, we observed synaptic contacts on L-ITCc dendrites from nociceptive intralaminar thalamic nuclei. We propose that, during salient sensory stimulation, L-ITCcs disinhibit local and distant principal neurons, acting as “hub cells,” to orchestrate the activity of a distributed network. PMID:25653362

  18. Diminished hippocalcin expression in Huntington's disease brain does not account for increased striatal neuron vulnerability as assessed in primary neurons.

    PubMed

    Rudinskiy, Nikita; Kaneko, Yoshio A; Beesen, Ayshe Ana; Gokce, Ozgun; Régulier, Etienne; Déglon, Nicole; Luthi-Carter, Ruth

    2009-10-01

    Hippocalcin is a neuronal calcium sensor protein previously implicated in regulating neuronal viability and plasticity. Hippocalcin is the most highly expressed neuronal calcium sensor in the medium spiny striatal output neurons that degenerate selectively in Huntington's disease (HD). We have previously shown that decreased hippocalcin expression occurs in parallel with the onset of disease phenotype in mouse models of HD. Here we show by in situ hybridization histochemistry that hippocalcin RNA is also diminished by 63% in human HD brain. These findings lead us to hypothesize that diminished hippocalcin expression might contribute to striatal neurodegeneration in HD. We tested this hypothesis by assessing whether restoration of hippocalcin expression would decrease striatal neurodegeneration in cellular models of HD comprising primary striatal neurons exposed to mutant huntingtin, the mitochondrial toxin 3-nitropropionic acid or an excitotoxic concentration of glutamate. Counter to our hypothesis, hippocalcin expression did not improve the survival of striatal neurons under these conditions. Likewise, expression of hippocalcin together with interactor proteins including the neuronal apoptosis inhibitory protein did not increase the survival of striatal cells in cellular models of HD. These results indicate that diminished hippocalcin expression does not contribute to HD-related neurodegeneration.

  19. Anatomical and histological data on the ciliary ganglion in the Egyptian spiny mouse (Acomys cahirinus Desmarest).

    PubMed

    Nowak, Elzbieta; Kuder, Tadeusz; Szczurkowski, Aleksander; Kuchinka, Jacek

    2004-08-01

    The morphology and topography of the ciliary ganglion in the Egyptian spiny mouse were studied with use of histochemical and histological techniques. The ciliary ganglion of the Egyptian spiny mouse consisted of between 3 and 4 agglomerations of nerve cells. The largest was situated at the point where the ventral branch of the oculomotor nerve divides into two branches. The next two smaller aggregations were located on the superior and lateral surfaces of the optic nerve where it crossed the oculomotor nerve. From the main agglomerations of neurocytes arose between 3 and 4 intensively stained postganglionic cholinergic fibres. These followed the optic nerve to the eyeball. On the cross-sections of these bundles small agglomerations of neurocytes were observed. These decreased in size to only 2 or 3 cells towards the sclera. The ganglionic neurocytes in the largest ganglion varied from 15 to 30 microm in diameter. They were distributed uniformly over the whole surface of the sections. All the ganglia had connective capsules.

  20. Reproductive and metabolic responses of desert adapted common spiny male mice (Acomys cahirinus) to vasopressin treatment.

    PubMed

    Bukovetzky, Elena; Fares, Fuad; Schwimmer, Hagit; Haim, Abraham

    2012-08-01

    Sufficient amounts of water and food are important cues for reproduction in an unpredictable environment. We previously demonstrated that increased osmolarity levels, or exogenous vasopressin (VP) treatment halt reproduction of desert adapted golden spiny mice Acomys russatus. In this research we studied gonad regulation by VP and food restriction (FR) in desert adapted common spiny mouse (A. cahirinus) males, kept under two different photoperiod regimes-short (SD-8L:16D) and long (LD-16L:8D) days. Mice were treated with VP, FR, and VP+FR for three weeks. Response was assessed from changes in relative testis mass, serum testosterone levels and mRNA receptor gene expression of VP, aldosterone and leptin in treated groups, compared with their controls. SD-acclimation increased testosterone levels, VP treatment decreased expression of aldosterone mRNA receptor in the testes of SD-acclimated males. FR under SD-conditions resulted in testosterone decrease and elevation of VP- receptor gene expression in testes. Aldosterone receptor mRNA expression was also detected in WAT. These results support the idea that water and food availability in the habitat may be used as signals for activating the reproductive system through direct effects of VP, aldosterone and leptin on the testes or through WAT by indirect effects.

  1. Sympatric incipient speciation of spiny mice Acomys at "Evolution Canyon," Israel.

    PubMed

    Hadid, Yarin; Pavlícek, Tomás; Beiles, Avigdor; Ianovici, Ron; Raz, Shmuel; Nevo, Eviatar

    2014-01-21

    Does the paucity of empirical evidence of sympatric speciation in nature reflect reality, despite theoretical support? Or is it due to inappropriate searches in nature with overly restrictive assumptions and an incorrect null hypothesis? Spiny mice, Acomys, described here at Evolution Canyon (EC) incipiently and sympatrically speciate owing to microclimatic interslope divergence. The opposite slopes at EC vary dramatically, physically and biotically, representing the dry and hot south-facing slope savannoid-African continent ["African" slope (AS)], abutting with the north-facing slope forested south-European continent ["European" slope (ES)]. African-originated spiny mice, of the Acomys cahirinus complex, colonized Israel 30,000 y ago based on fossils. Genotypically, we showed significantly higher genetic diversity of mtDNA and amplified fragment length polymorphism of Acomys on the AS compared with the ES. This is also true regionally across Israel. In complete mtDNA, 25% of the haplotypes at EC were slope-biased. Phenotypically, the opposite slope's populations also showed adaptive morphology, physiology, and behavior divergence paralleling regional populations across Israel. Preliminary tests indicate slope-specific mate choices. Colonization of Acomys at the EC first occurred on the AS and then moved to the ES. Strong slope-specific natural selection (both positive and negative) overrules low interslope gene flow. Both habitat slope selection and mate choices suggest ongoing incipient sympatric speciation. We conclude that Acomys at the EC is ecologically and genetically adaptively, incipiently, sympatrically speciating on the ES owing to adaptive microclimatic natural selection.

  2. Distribution of androgen and progesterone receptors in the spiny mouse (Acomys cahirinus) ovary during postnatal life.

    PubMed

    Hułas-Stasiak, Monika; Gawron, Antoni

    2010-03-01

    This study describes the localization of androgen (AR) and progesterone (PR) receptors in the developing ovary in the spiny mouse. The immunohistochemical analysis showed for the first time the expression of AR and PR proteins in the ovary as early as in one day-old females. Both AR and PR were present in germinal epithelium cells, stromal cells as well as in the granulosa and theca layer of ovarian follicles. On days 7, 14, 21, 30, 60 and 90, the distribution of AR and PR depended on the stage of follicular development rather than on the animal's age. A novel observation was that PR protein was detected not only in granulosa cells of preovulatory follicles, but also in the growing and early antral follicles. It was demonstrated that there is a different pattern of AR and PR immunoexpression throughout folliculogenesis. In contrast to AR, whose expression decreased during follicular development, the PR immunostaining increased during this time. It is concluded that androgens and progesterone may play an important role in the early stage of follicular development in the spiny mouse.

  3. Redefining metamorphosis in spiny lobsters: molecular analysis of the phyllosoma to puerulus transition in Sagmariasus verreauxi.

    PubMed

    Ventura, Tomer; Fitzgibbon, Quinn P; Battaglene, Stephen C; Elizur, Abigail

    2015-08-27

    The molecular understanding of crustacean metamorphosis is hindered by small sized individuals and inability to accurately define molt stages. We used the spiny lobster Sagmariasus verreauxi where the large, transparent larvae enable accurate tracing of the transition from a leaf-shaped phyllosoma to an intermediate larval-juvenile phase (puerulus). Transcriptomic analysis of larvae at well-defined stages prior to, during, and following this transition show that the phyllosoma-puerulus metamorphic transition is accompanied by vast transcriptomic changes exceeding 25% of the transcriptome. Notably, genes previously identified as regulating metamorphosis in other crustaceans do not fluctuate during this transition but in the later, morphologically-subtle puerulus-juvenile transition, indicating that the dramatic phyllosoma-puerulus morphological shift relies on a different, yet to be identified metamorphic mechanism. We examined the change in expression of domains and gene families, with focus on several key genes. Our research implies that the separation in molecular triggering systems between the phyllosoma-puerulus and puerulus-juvenile transitions might have enabled the extension of the oceanic phase in spiny lobsters. Study of similar transitions, where metamorphosis is uncoupled from the transition into the benthic juvenile form, in other commercially important crustacean groups might show common features to point on the evolutionary advantage of this two staged regulation.

  4. Redefining metamorphosis in spiny lobsters: molecular analysis of the phyllosoma to puerulus transition in Sagmariasus verreauxi

    PubMed Central

    Ventura, Tomer; Fitzgibbon, Quinn P.; Battaglene, Stephen C.; Elizur, Abigail

    2015-01-01

    The molecular understanding of crustacean metamorphosis is hindered by small sized individuals and inability to accurately define molt stages. We used the spiny lobster Sagmariasus verreauxi where the large, transparent larvae enable accurate tracing of the transition from a leaf-shaped phyllosoma to an intermediate larval-juvenile phase (puerulus). Transcriptomic analysis of larvae at well-defined stages prior to, during, and following this transition show that the phyllosoma-puerulus metamorphic transition is accompanied by vast transcriptomic changes exceeding 25% of the transcriptome. Notably, genes previously identified as regulating metamorphosis in other crustaceans do not fluctuate during this transition but in the later, morphologically-subtle puerulus-juvenile transition, indicating that the dramatic phyllosoma-puerulus morphological shift relies on a different, yet to be identified metamorphic mechanism. We examined the change in expression of domains and gene families, with focus on several key genes. Our research implies that the separation in molecular triggering systems between the phyllosoma-puerulus and puerulus-juvenile transitions might have enabled the extension of the oceanic phase in spiny lobsters. Study of similar transitions, where metamorphosis is uncoupled from the transition into the benthic juvenile form, in other commercially important crustacean groups might show common features to point on the evolutionary advantage of this two staged regulation. PMID:26311524

  5. Competition with stone crabs drives juvenile spiny lobster abundance and distribution.

    PubMed

    Behringer, Donald C; Hart, John E

    2017-02-28

    Interspecific competition is assumed to have a strong influence on the population dynamics of competing species, but is not easily demonstrated for mobile species in the wild. In the Florida Keys (USA), anecdotal observations have long pointed to an inverse relationship in abundance of two large decapod crustaceans found co-occurring in hard-bottom habitat, the stone crab Menippe mercenaria and the Caribbean spiny lobster Panulirus argus. We used them to explicitly test whether competition for a renewable resource (shelter) can drive the abundance and distribution of the inferior competitor. We first explored this relationship in shelter competition mesocosm experiments to determine the competitively dominant species. Results showed that stone crabs are clearly the dominant competitors regardless of the number of lobsters present, the presence of co-sheltering species such as the spider crab, Damithrax spinosissimus, or the order of introduction of competitors into the mesocosm. We also found that lobsters use chemical cues from stone crabs to detect and avoid them. We then tested the ramifications of this competitive dominance in the field by manipulating stone crab abundance and then tracking the abundance and distribution of spiny lobsters through time. Increased stone crab abundance immediately resulted in decreased lobster abundance and increased aggregation. The opposite occurred on sites where stone crabs were removed. When we stopped removing stone crabs from these sites, they soon returned and lobster abundance decreased. This study explicitly demonstrated that interspecific competition can drive population dynamics between these species, and ultimately, community composition in these shallow water habitats.

  6. Host behavior alters spiny lobster-viral disease dynamics: a simulation study.

    PubMed

    Dolan, Thomas W; Butler, Mark J; Shields, Jeffrey D

    2014-08-01

    Social behavior confers numerous benefits to animals but also risks, among them an increase in the spread of pathogenic diseases. We examined the trade-off between risk of predation and disease transmission under different scenarios of host spatial structure and disease avoidance behavior using a spatially explicit, individual-based model of the host pathogen interaction between juvenile Caribbean spiny lobster (Panulirus argus) and Panulirus argus Virus 1 (PaV1). Spiny lobsters are normally social but modify their behavior to avoid diseased conspecifics, a potentially effective means of reducing transmission but one rarely observed in the wild. We found that without lobster avoidance of diseased conspecifics, viral outbreaks grew in intensity and duration in simulations until the virus was maintained continuously at unrealistically high levels. However, when we invoked disease avoidance at empirically observed levels, the intensity and duration of outbreaks was reduced and the disease extirpated within five years. Increased lobster (host) spatial aggregation mimicking that which occurs when sponge shelters for lobsters are diminished by harmful algal blooms, did not significantly increase PaV1 transmission or persistence in lobster populations. On the contrary, behavioral aversion of diseased conspecifics effectively reduced viral prevalence, even when shelters were limited, which reduced shelter availability for all lobsters but increased predation, especially of infected lobsters. Therefore, avoidance of diseased conspecifics selects against transmission by contact, promotes alternative modes of transmission, and results in a more resilient host-pathogen system.

  7. Pollution biomarkers in the spiny lizard (Sceloporus spp.) from two suburban populations of Monterrey, Mexico.

    PubMed

    Aguilera, Carlos; del Pliego, Pamela González; Alfaro, Roberto Mendoza; Lazcano, David; Cruz, Julio

    2012-11-01

    Environmental pollution may severely impact reptile species in urbanized areas. The magnitude of the impact is analyzed in the present study using lizard tail tips for the quantitative evaluation of enzymatic biomarkers of pollution. Spiny lizards (Sceloporus serrifer and S. torquatus) were collected from two suburban localities in the Monterrey metropolitan area, Mexico: Chipinque Ecological Park, a natural protected area, and El Carmen Industrial Park (IP), a highly polluted site. Different enzymes were used as biomarkers including: acetylcholinesterase (AChE), butyrylcholinesterase (BChE), carboxylesterase (CaE), alkaline phosphatase (ALP), acid phosphatase (ACP), superoxide dismutase (SOD) and glutathione S-transferase (GST). The levels of AChE, BChE and ACP activity were not significantly different between localities. AChE and BChE, commonly used as biomarkers of neurotoxic polluting agents (e.g. organophosphate pesticides) do not appear to be affecting the populations from the study locations. In contrast, the levels of CaE, GST, ALP and SOD were significantly different between the localities. These biomarkers are regularly associated with oxidative stress and processes of detoxification, and generally indicate pollution caused by heavy metals or hydrocarbons, which are common in industrial sites. The data resulting from the analysis of these biomarkers indicate that these polluting agents are affecting the populations of Sceloporus in IP. The present work validates the possibility of conducting additional ecotoxicological studies using biomarkers in combination with a nondestructive sampling technique in species of spiny lizards that are abundant in many North America areas.

  8. Inheritance of flower color and spininess in safflower (Carthamus tinctorius L.).

    PubMed

    Pahlavani, M H; Mirlohi, A F; Saeidi, G

    2004-01-01

    Safflower (Carthamus tinctorius L.) flowers are used for coloring and flavoring food and also as fresh-cut and dried flowers. The most important characteristics which contribute to the ornamental value of safflower are flower color and spinelessness. The objective of this study was to determine the inheritance mode and the number of genes controlling spininess and flower color in some Iranian genotypes of safflower. The results indicated that the existence of spines on the leaves and bracts of safflower is controlled by a single dominant gene in which the spiny phenotype was completely dominant to spineless. In some crosses, flower color was controlled by two epistatic loci each with two alleles, resulting in a ratio of 13:3 in the segregating F2 population for plants with orange and yellow flowers. Also, other mechanisms of genetic control, such as duplicate dominance and duplicate recessive types of epistasis, were observed for flower color in other crosses that led to ratios of 7:9 and 15:1 for plants with orange and yellow flowers, respectively. The results suggest that for ornamental use or in the food dying industry, genotypes with orange or yellow flowers and without spines on the leaves and bracts can be produced.

  9. Pathogenicity and Infection Cycle of Vibrio owensii in Larviculture of the Ornate Spiny Lobster (Panulirus ornatus)

    PubMed Central

    Goulden, Evan F.; Hall, Michael R.; Bourne, David G.; Pereg, Lily L.

    2012-01-01

    The type strain of Vibrio owensii (DY05) was isolated during an epizootic of aquaculture-reared larvae (phyllosomas) of the ornate spiny lobster (Panulirus ornatus). V. owensii DY05 was formally demonstrated to be the etiological agent of a disease causing rapid and reproducible larval mortality with pathologies similar to those seen during disease epizootics. Vectored challenge via the aquaculture live feed organism Artemia (brine shrimp) caused consistent cumulative mortality rates of 84 to 89% after 72 h, in contrast to variable mortality rates seen after immersion challenge. Histopathological examination of vector-challenged phyllosomas revealed bacterial proliferation in the midgut gland (hepatopancreas) concomitant with epithelial cell necrosis. A fluorescent-protein-labeled V. owensii DY05 transconjugant showed dispersal of single cells in the foregut and hepatopancreas 6 h postexposure, leading to colonization of the entire hepatopancreas within 18 h and eventually systemic infection. V. owensii DY05 is a marine enteropathogen highly virulent to P. ornatus phyllosoma that uses vector-mediated transmission and release from host association to a planktonic existence to perpetuate transfer. This understanding of the infection process will improve targeted biocontrol strategies and enhance the prospects of commercially viable larviculture for this valuable spiny lobster species. PMID:22307306

  10. The Rise of Jaw Protrusion in Spiny-Rayed Fishes Closes the Gap on Elusive Prey.

    PubMed

    Bellwood, David R; Goatley, Christopher H R; Bellwood, Orpha; Delbarre, Daniel J; Friedman, Matt

    2015-10-19

    Jaw protrusion is one of the most important innovations in vertebrate feeding over the last 400 million years [1, 2]. Protrusion enables a fish to rapidly decrease the distance between itself and its prey [2, 3]. We assessed the evolution and functional implications of jaw protrusion in teleost fish assemblages from shallow coastal seas since the Cretaceous. By examining extant teleost fishes, we identified a robust morphological predictor of jaw protrusion that enabled us to predict the extent of jaw protrusion in fossil fishes. Our analyses revealed increases in both average and maximum jaw protrusion over the last 100 million years, with a progressive increase in the potential impact of fish predation on elusive prey. Over this period, the increase in jaw protrusion was initially driven by a taxonomic restructuring of fish assemblages, with an increase in the proportion of spiny-rayed fishes (Acanthomorpha), followed by an increase in the extent of protrusion within this clade. By increasing the ability of fishes to catch elusive prey [2, 4], jaw protrusion is likely to have fundamentally changed the nature of predator-prey interactions and may have contributed to the success of the spiny-rayed fishes, the dominant fish clade in modern oceans [5].

  11. Molecular evidence that the spiny mouse (Acomys) is more closely related to gerbils (Gerbillinae) than to true mice (Murinae).

    PubMed

    Chevret, P; Denys, C; Jaeger, J J; Michaux, J; Catzeflis, F M

    1993-04-15

    Spiny mice of the genus Acomys traditionally have been classified as members of the Murinae, a subfamily of rodents that also includes rats and mice with which spiny mice share a complex set of morphological characters, including a unique molar pattern. The origin and evolution of this molar pattern, documented by many fossils from Southern Asia, support the hypothesis of the monophyly of Acomys and all other Murinae. This view has been challenged by immunological studies that have suggested that Acomys is as distantly related to mice (Mus) as are other subfamilies (e.g., hamsters: Cricetinae) of the muroid rodents. We present molecular evidence derived from DNA.DNA hybridization data that indicate that the spiny mouse Acomys and two African genera of Murinae, Uranomys and Lophuromys, constitute a monophyletic clade, a view that was recently suggested on the basis of dental characters. However, our DNA.DNA hybridization data also indicate that the spiny mice (Acomys) are more closely related to gerbils (Gerbillinae) than to the true mice and rats (Murinae) with which they have been classified. Because Acomys and the brush-furred mice Uranomys and Lophuromys share no derived morphological characters with the Gerbillinae, their murine morphology must have evolved by convergence, including the molar pattern previously considered to support the monophyly of the Murinae.

  12. Molecular evidence that the spiny mouse (Acomys) is more closely related to gerbils (Gerbillinae) than to true mice (Murinae).

    PubMed Central

    Chevret, P; Denys, C; Jaeger, J J; Michaux, J; Catzeflis, F M

    1993-01-01

    Spiny mice of the genus Acomys traditionally have been classified as members of the Murinae, a subfamily of rodents that also includes rats and mice with which spiny mice share a complex set of morphological characters, including a unique molar pattern. The origin and evolution of this molar pattern, documented by many fossils from Southern Asia, support the hypothesis of the monophyly of Acomys and all other Murinae. This view has been challenged by immunological studies that have suggested that Acomys is as distantly related to mice (Mus) as are other subfamilies (e.g., hamsters: Cricetinae) of the muroid rodents. We present molecular evidence derived from DNA.DNA hybridization data that indicate that the spiny mouse Acomys and two African genera of Murinae, Uranomys and Lophuromys, constitute a monophyletic clade, a view that was recently suggested on the basis of dental characters. However, our DNA.DNA hybridization data also indicate that the spiny mice (Acomys) are more closely related to gerbils (Gerbillinae) than to the true mice and rats (Murinae) with which they have been classified. Because Acomys and the brush-furred mice Uranomys and Lophuromys share no derived morphological characters with the Gerbillinae, their murine morphology must have evolved by convergence, including the molar pattern previously considered to support the monophyly of the Murinae. PMID:8475093

  13. 1-/sup 14/C-n-hexadecane disposition in the spiny lobster, Panulirus argus and the American lobster, Homarus americanus

    SciTech Connect

    Little, P.J.; James, M.O.; Foureman, G.L.; Weatherby, R.P.; Bend, J.R.

    1986-05-01

    1-/sup 14/C-n-hexadecane, a model compound for the non-volatile aliphatic hydrocarbon components of crude oil, was administered by intrapericardial injection to the spiny lobster, Panulirus argus, and the clawed or American lobster, Homarus americanus. Experiments were conducted in Florida (spiny lobster) and Maine (American lobster). The animals were sacrificed at various times from 0.5 hr to 8 wks after administration of the dose. The tissues and fluids were analyzed for /sup 14/C content by digestion or catalytic oxidation and liquid scintillation counting. Selected tissues (hepatopancreas, tail muscle and hemolymph) were extracted with ethyl acetate to allow quantitation of the unmetabolized n-hexadecane by thin layer chromatography. n-Hexadecane-derived radioactivity was very persistent in both the spiny lobster (t1/2 = 4.6 wk) and the American lobster (t1/2 = 11.2 wk). In both lobsters, the hepatopancreas (HP) acquired the highest specific activity and the tail muscle had the longest half life for elimination from an individual tissue. Although hexadecane was metabolized more rapidly in the HP of the spiny lobster than in the HP of the American lobster, unmetabolized hexadecane persisted in the HPs of both species for at least 8 weeks after the dose (the longest time studied).

  14. 76 FR 68711 - Amendments to the Reef Fish, Spiny Lobster, Queen Conch and Coral and Reef Associated Plants and...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-11-07

    ..., Queen Conch and Coral and Reef Associated Plants and Invertebrates Fishery Management Plans of Puerto... Puerto Rico and the U.S. Virgin Islands, and Amendment 3 to the FMP for Corals and Reef Associated Plants... framework procedures for the spiny lobster and Caribbean corals and reef associated plants and...

  15. 76 FR 59102 - Fisheries of the Caribbean, Gulf of Mexico, and South Atlantic; Spiny Lobster Fishery of the Gulf...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-09-23

    ... difficulties for law enforcement personnel in determining if the lobster were originally of legal size. This... Act, and other applicable law, subject to further consideration after public comment. This proposed..., 800 North Capitol Street, NW., Suite 700, Washington, DC. A spiny lobster trap, buoy, or rope in...

  16. 76 FR 75488 - Fisheries of the Caribbean, Gulf of Mexico, and South Atlantic; Spiny Lobster Fishery of the Gulf...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-12-02

    ... provisions of the Magnuson-Stevens Act, and other applicable law. This final rule has been determined to be... Florida. A spiny lobster trap, buoy, or rope in the EEZ off Florida, during periods not authorized in this..., see Sec. 640.29). An owner of such trap, buoy, or rope remains subject to appropriate civil...

  17. 1-14C-n-hexadecane disposition in the spiny lobster, Panulirus argus and the American lobster, Homarus americanus.

    PubMed

    Little, P J; James, M O; Foureman, G L; Weatherby, R P; Bend, J R

    1986-01-01

    1-14C-n-hexadecane, a model compound for the non-volatile aliphatic hydrocarbon components of crude oil, was administered by intrapericardial injection to the spiny lobster, Panulirus argus, and the clawed or American lobster, Homarus americanus. Experiments were conducted in Florida (spiny lobster) and Maine (American lobster). The animals were sacrificed at various times from 0.5 hr to 8 wks after administration of the dose. The tissues and fluids were analyzed for 14C content by digestion or catalytic oxidation and liquid scintillation counting. Selected tissues (hepatopancreas, tail muscle and hemolymph) were extracted with ethyl acetate to allow quantitation of the unmetabolized n-hexadecane by thin layer chromatography. n-Hexadecane-derived radioactivity was very persistent in both the spiny lobster (t1/2 = 4.6 wk) and the American lobster (t1/2 = 11.2 wk). In both lobsters, the hepatopancreas (HP) acquired the highest specific activity and the tail muscle had the longest half life for elimination from an individual tissue. Although hexadecane was metabolized more rapidly in the HP of the spiny lobster than in the HP of the American lobster, unmetabolized hexadecane persisted in the HPs of both species for at least 8 weeks after the dose (the longest time studied).

  18. Phylogenetic and molecular analysis of HTLV-1 isolates from a medium sized town in northern of Brazil: tracing a common origin of the virus from the most endemic city in the country.

    PubMed

    Magalhães, Themístocles; Mota-Miranda, Aline Cristina; Alcantara, Luiz Carlos Junior; Olavarria, Viviana; Galvão-Castro, Bernardo; Rios-Grassi, Maria Fernanda

    2008-11-01

    Salvador-Bahia has the highest prevalence of HTLV-1 infection in Brazil; about 2% of the population is infected. In this city, the prevalence of HTLV in pregnant women is 1%. There is no data of the HTLV-1 prevalence in others cities of the Bahia's Recôncavo, where the population has similar social and demography characteristics to those from Salvador. Our aim was to evaluate the seroprevalence of HTLV in pregnant women in Cruz das Almas-Bahia, a medium-sized city from the Bahia's Recôncavo. All individuals were tested for HTLV (ELISA) and the positive samples were confirmed by Western Blot. Phylogenetic analyses of the total LTR region were performed in all positive samples. We tested 408 samples (45.4% of the estimate pregnant women population) between June 1st and October 31, 2005. The prevalence of HTLV-1 infection was 0.98%. In addition, all isolated virus were grouped in the subtype HTLV-1a, in the Latin American group. Our results suggest that the introduction of HTLV-1 occurred after the slave trade into Salvador. In addition, HTLV-1-infection should be screened during the pregnancy in women originating from HTLV-1 endemic areas.

  19. Development and process evaluation of the participatory and action-oriented empowerment model facilitated by occupational health nurses for workplace health promotion in small and medium-sized enterprises.

    PubMed

    Nishikido, Noriko; Matsuda, Kazumi; Fukuda, Eiko; Motoki, Chiharu; Tsutaki, Miho; Kawakami, Yuko; Yuasa, Akiko; Iijima, Miyoko; Tanaka, Mika; Hirata, Mamoru; Hojoh, Minoru; Ikeda, Tomoko; Maeda, Kazutoshi; Miyoshi, Yukari; Arai, Sumiko; Mitsuhashi, Hiroyuki

    2007-01-01

    The objective of this study is to develop an available empowerment model for workplace health promotion (WHP) in small and medium-sized enterprises (SMEs) and to evaluate its applicability and feasibility. Semi-structured interviews with employers and workers in SMEs were conducted to assess their actual requirements for support. The structure of our new empowerment model was discussed and established through several rounds of focus group meetings with occupational safety and health researchers and practitioners on the basis of results of our interviews. We developed a new participatory and action-oriented empowerment model based on needs for support of employers and workers in SMEs. This new model consists of three originally developed tools: an action checklist, an information guidebook, and a book of good practices. As the facilitators, occupational health nurses (OHNs) from health insurance associations were trained to empower employers and workers using these tools. Approximately 80 SMEs (with less than 300 employees) were invited to participate in the model project. With these tools and continued empowerment by OHNs, employers and workers were able to smoothly work on WHP. This newly developed participatory and action-oriented empowerment model that was facilitated by trained OHNs appears to be both applicable and feasible for WHP in SMEs in Japan.

  20. An efficient, convenient synthesis of novel medium-sized 13H-dibenzo[d,h][1,3,7]oxadiazecine-8,14-dione macrolides as anticipated antineoplastic agents.

    PubMed

    Abdel-Hafez, Atef Abdel-Monem

    2002-07-01

    A series of novel medium-sized 13H-dibenzo[d,h][1,3,7]oxadiazecine-8,14-dione macrolides (18-27, 30, 32) were synthesized in an ongoing effort to develop new antineoplastic agents. The synthon 2-(2-aminobenzoylamino)-benzoic acid (7), for preparation of the target compounds, was prepared via the reaction of isatoic anhydride 5 and anthranilic acid 6. Nine compounds (18-20, 24-27, 30, 32) were subjected to National Cancer Institute (NCI) in vitro disease-oriented human cells screening panel assay. Among the compounds tested, 6-benzyl-13H-dibenzo[d,h][1,3,7]oxadiazecine-8,14-dione (26, NSC 721327), bearing the benzyl group at position 6, showed cytotoxic activity and subpanel selectivity against leukemia (CCRF-CEM), colon (HCC-2998), CNS (SNB-75) and melanoma (UACC-257) panels at log(10) GI(50) (M), compound concentration that inhibits 50% of cell growth, ranging from -4.08 to -4.59.

  1. Crystallographic X-ray analyses of Yb@C(2v)(3)-C80 reveal a feasible rule that governs the location of a rare earth metal inside a medium-sized fullerene.

    PubMed

    Lu, Xing; Lian, Yongfu; Beavers, Christine M; Mizorogi, Naomi; Slanina, Zdenek; Nagase, Shigeru; Akasaka, Takeshi

    2011-07-20

    Single crystal X-ray diffraction studies of Yb@C(2v)(3)-C(80)·Ni(II)(OEP)·CS(2)·1.5C(6)H(6) (OEP = octaethylporphinate) reveal that a relatively flat region of the fullerene interacts with the Ni(II)(OEP) molecule, featuring shape-matching interactions. Surprisingly, it is found that the internal metal is located under a hexagonal carbon ring apart from the 2-fold axis of the C(2v)(3)-C(80) cage, presenting the first example of metallofullerenes with an asymmetrically positioned metal. Such an anomalous location of Yb(2+) is associated with its strong ability to pursue a large coordination number and the lack of hexagon along the C(2) axis of C(2v)(3)-C(80). It is accordingly assumed that a suitable cage hexagon is most likely to be preferred by the single rare earth metal to stay behind inside a medium-sized fullerene, such as C(80) and C(82).

  2. Calculating core-level excitations and X-ray absorption spectra of medium-sized closed-shell molecules with the algebraic-diagrammatic construction scheme for the polarization propagator.

    PubMed

    Wenzel, Jan; Wormit, Michael; Dreuw, Andreas

    2014-10-05

    Core-level excitations are generated by absorption of high-energy radiation such as X-rays. To describe these energetically high-lying excited states theoretically, we have implemented a variant of the algebraic-diagrammatic construction scheme of second-order ADC(2) by applying the core-valence separation (CVS) approximation to the ADC(2) working equations. Besides excitation energies, the CVS-ADC(2) method also provides access to properties of core-excited states, thereby allowing for the calculation of X-ray absorption spectra. To demonstrate the potential of our implementation of CVS-ADC(2), we have chosen medium-sized molecules as examples that have either biological importance or find application in organic electronics. The calculated results of CVS-ADC(2) are compared with standard TD-DFT/B3LYP values and experimental data. In particular, the extended variant, CVS-ADC(2)-x, provides the most accurate results, and the agreement between the calculated values and experiment is remarkable.

  3. Comparison between surgery and physiotherapy in the treatment of small and medium-sized tears of the rotator cuff: A randomised controlled study of 103 patients with one-year follow-up.

    PubMed

    Moosmayer, S; Lund, G; Seljom, U; Svege, I; Hennig, T; Tariq, R; Smith, H-J

    2010-01-01

    In order to compare the outcome from surgical repair and physiotherapy, 103 patients with symptomatic small and medium-sized tears of the rotator cuff were randomly allocated to one of the two approaches. The primary outcome measure was the Constant score, and secondary outcome measures included the self-report section of the American Shoulder and Elbow Surgeons score, the Short Form 36 Health Survey and subscores for shoulder movement, pain, strength and patient satisfaction. Scores were taken at baseline and after six and 12 months by a blinded assessor. Nine patients (18%) with insufficient benefit from physiotherapy after at least 15 treatment sessions underwent secondary surgical treatment. Analysis of between-group differences showed better results for the surgery group on the Constant scale (difference 13.0 points, p - 0.002), on the American Shoulder and Elbow surgeons scale (difference 16.1 points, p < 0.0005), for pain-free abduction (difference 28.8 degrees , p = 0.003) and for reduction in pain (difference on a visual analogue scale -1.7 cm, p < 0.0005).

  4. Selective elimination of glutamatergic synapses on striatopallidal neurons in Parkinson disease models.

    PubMed

    Day, Michelle; Wang, Zhongfeng; Ding, Jun; An, Xinhai; Ingham, Cali A; Shering, Andrew F; Wokosin, David; Ilijic, Ema; Sun, Zhuoxin; Sampson, Allan R; Mugnaini, Enrico; Deutch, Ariel Y; Sesack, Susan R; Arbuthnott, Gordon W; Surmeier, D James

    2006-02-01

    Parkinson disease is a common neurodegenerative disorder that leads to difficulty in effectively translating thought into action. Although it is known that dopaminergic neurons that innervate the striatum die in Parkinson disease, it is not clear how this loss leads to symptoms. Recent work has implicated striatopallidal medium spiny neurons (MSNs) in this process, but how and precisely why these neurons change is not clear. Using multiphoton imaging, we show that dopamine depletion leads to a rapid and profound loss of spines and glutamatergic synapses on striatopallidal MSNs but not on neighboring striatonigral MSNs. This loss of connectivity is triggered by a new mechanism-dysregulation of intraspine Cav1.3 L-type Ca(2+) channels. The disconnection of striatopallidal neurons from motor command structures is likely to be a key step in the emergence of pathological activity that is responsible for symptoms in Parkinson disease.

  5. Genetically-directed Sparse Neuronal Labeling in BAC Transgenic Mice through Mononucleotide Repeat Frameshift

    PubMed Central

    Lu, Xiao-Hong; Yang, X. William

    2017-01-01

    Mosaicism with Repeat Frameshift (MORF) allows a single Bacterial Artificial Chromosome (BAC) transgene to direct sparse labeling of genetically-defined neuronal populations in mice. The BAC transgene drives cell-type-specific transcription of an out-of-frame mononucleotide repeat that is placed between a translational start codon and a membrane-bound fluorescent protein lacking its start codon. The stochastic frameshift of the unstable repeat DNA in a subset of BAC-expressing neurons results in the in-frame translation of the reporter protein hence the sparse neuronal labeling. As a proof-of-concept, we generated D1-dopamine receptor (D1) BAC MORF mice that label about 1% striatal D1-expressing medium spiny neurons and allow visualization of their dendrites. These mice enable the study of D1-MSN dendrite development in wildtype mice, and its degeneration in a mouse model of Huntington’s disease. PMID:28272512

  6. Ontogenetic Change in the Regional Distribution of Dehydroepiandrosterone-Synthesizing Enzyme and the Glucocorticoid Receptor in the Brain of the Spiny Mouse (Acomys cahirinus).

    PubMed

    Quinn, Tracey A; Ratnayake, Udani; Dickinson, Hayley; Castillo-Melendez, Margie; Walker, David W

    2016-01-01

    The androgen dehydroepiandrosterone (DHEA) has trophic and anti-glucocorticoid actions on brain growth. The adrenal gland of the spiny mouse (Acomys cahirinus) synthesizes DHEA. The aim of this study was to determine whether the brain of this precocial species is also able to produce DHEA de novo during fetal, neonatal and adult life. The expression of P450c17 and cytochrome b5 (Cytb5), the enzyme and accessory protein responsible for the synthesis of DHEA, was determined in fetal, neonatal and adult brains by immunocytochemistry, and P450c17 bioactivity was determined by the conversion of pregnenolone to DHEA. Homogenates of fetal brain produced significantly more DHEA after 48 h in culture (22.46 ± 2.0 ng/mg tissue) than adult brain homogenates (5.04 ± 2.0 ng/mg tissue; p < 0.0001). P450c17 and Cytb5 were co-expressed in fetal neurons but predominantly in oligodendrocytes and white matter tracts in the adult brain. Because DHEA modulates glucocorticoids actions, the expression of the glucocorticoid receptor (GR) was also determined. In the brainstem, medulla, midbrain, and cerebellum, the predominant GR localization changed from neurons in the fetal brain to oligodendrocytes and white matter tracts in the adult brain. The change of expression of P450c17, Cytb5 and GR proteins with cell type, brain region and developmental age indicates that DHEA is an endogenous neurosteroid in this species that may have important trophic and stress-modifying actions during both prenatal and postnatal life.

  7. What neurons hide behind calretinin immunoreactivity in the human gut?

    PubMed

    Beuscher, Nicholas; Jabari, Samir; Strehl, Johanna; Neuhuber, Winfried; Brehmer, Axel

    2014-04-01

    Calretinin (CALR) is often used as an immunohistochemical marker for the histopathological diagnosis of human intestinal neuropathies. However, little is known about its distribution pattern with respect to specific human enteric neuron types. Prior studies revealed CALR in both myenteric and submucosal neurons, most of which colabel with choline acetyl transferase (ChAT). Here, we specified the chemical code of CALR-positive neurons in small and large intestinal wholemounts in a series of 28 patients. Besides other markers, we evaluated the labeling pattern of CALR in combination with vasoactive intestinal peptide (VIP). In colonic submucosa, CALR and VIP were almost completely colocalized in about three-quarters of all submucosal neurons. In the small intestinal submucosa, both the colocalization rate of CALR and VIP as well as the proportion of these neurons were lower (about one-third). In the myenteric plexus of both small intestine and colon, CALR amounted to 11 and 10 %, respectively, whereas VIP to 5 and 4 % of the whole neuron population, respectively. Colocalization of both markers was found in only 2 and 3 % of myenteric neurons, respectively. In section specimens, nerve fibers coreactive for CALR and VIP were found in the mucosa but not in the muscle coat. Summarizing the present and earlier results, CALR was found in at least one submucosal and two myenteric neuron populations. Submucosal CALR+/VIP+/ChAT± neurons innervate mucosal structures. Furthermore, CALR immunoreactivity in the myenteric plexus was observed in morphological type II (supposed primary afferent) and spiny type I (supposed inter- or motor-) neurons.

  8. Morphology and physiology of excitatory neurons in layer 6b of the somatosensory rat barrel cortex.

    PubMed

    Marx, Manuel; Feldmeyer, Dirk

    2013-12-01

    Neocortical lamina 6B (L6B) is a largely unexplored layer with a very heterogeneous cellular composition. To date, only little is known about L6B neurons on a systematic and quantitative basis. We investigated the morphological and electrophysiological properties of excitatory L6B neurons in the rat somatosensory barrel cortex using whole-cell patch-clamp recordings and simultaneous biocytin fillings. Subsequent histological processing and computer-assisted 3D reconstructions provided the basis for a classification of excitatory L6B neurons according to their structural and functional characteristics. Three distinct clusters of excitatory L6B neurons were identified: (C1) pyramidal neurons with an apical dendrite pointing towards the pial surface, (C2) neurons with a prominent, "apical"-like dendrite not oriented towards the pia, and (C3) multipolar spiny neurons without any preferential dendritic orientation. The second group could be further subdivided into three categories termed inverted, "tangentially" oriented and "horizontally" oriented neurons. Furthermore, based on the axonal domain two subcategories of L6B pyramidal cells were identified that had either a more barrel-column confined or an extended axonal field. The classification of excitatory L6B neurons provided here may serve as a basis for future studies on the structure, function, and synaptic connectivity of L6B neurons.

  9. Genetic evidence for p75NTR-dependent tetraploidy in cortical projection neurons from adult mice.

    PubMed

    López-Sánchez, Noelia; Frade, José M

    2013-04-24

    A subpopulation of chick retinal projection neurons becomes tetraploid during development, an event prevented by blocking antibodies against p75 neurotrophin receptor (p75(NTR)). We have used an optimized flow cytometric assay, based on the analysis of unfixed brain cell nuclei, to study whether p75(NTR)-dependent neuronal tetraploidization takes place in the cerebral cortex, giving rise to projection neurons as well. We show that 3% of neurons in both murine neocortex and chick telencephalic derivatives are tetraploid, and that in the mouse ~85% of these neurons express the immediate early genes Erg-1 and c-Fos, indicating that they are functionally active. Tetraploid cortical neurons (65-80%) express CTIP2, a transcription factor specific for subcortical projection neurons in the mouse neocortex. During the period in which these neurons are born, p75(NTR) is detected in differentiating neurons undergoing DNA replication. Accordingly, p75(NTR)-deficient mice contain a reduced proportion of both NeuN and CTIP2-positive neocortical tetraploid neurons, thus providing genetic evidence for the participation of p75(NTR) in the induction of neuronal tetraploidy in the mouse neocortex. In the striatum tetraploidy is mainly associated with long-range projection neurons as well since ~80% of tetraploid neurons in this structure express calbindin, a marker of neostriatal-matrix spiny neurons, known to establish long-range projections to the substantia nigra and globus pallidus. In contrast, only 20% of tetraploid cortical neurons express calbindin, which is mainly expressed in layers II-III, where CTIP2 is absent. We conclude that tetraploidy mainly affects long-range projection neurons, being facilitated by p75(NTR) in the neocortex.

  10. [Neuronal ageing].

    PubMed

    Piechota, Małgorzata; Sunderland, Piotr

    2014-01-01

    Ageing leads to irreversible alterations in the nervous system, which to various extent impair its functions such as capacity to learn and memory. In old neurons and brain, similarly to what may take place in other cells, there is increased oxidative stress, disturbed energetic homeostasis and metabolism, accumulation of damage in proteins and nucleic acids. Characteristic of old neurons are alterations in plasticity, synaptic transmission, sensitivity to neurotrophic factors and cytoskeletal changes. Some markers of senescence, whose one of them is SA-beta-galactosidase were used to show the process of neuronal ageing both in vitro, and in vivo. Some research suggest that, despite the fact that neurons are postmitotic cells, it is cell cycle proteins which play a certain role in their biology, e.g. differentiation. However, their role in neuronal ageing is not known or explained. Ageing is the serious factor of development of neurodegenerative diseases among others Alzheimer disease.

  11. DIFFERENTIATION OF NEURONAL TYPES AND SYNAPSES IN MYELINATING CULTURES OF MOUSE CEREBELLUM

    PubMed Central

    Wolf, Merrill K.

    1964-01-01

    The Holmes silver impregnation method has made possible the recognition of multiple neuronal types and synapses in myelinating cultures of mouse cerebellum. Well stained large and medium-sized neurons are always found in small numbers near ependymal formations and are considered to be roof nuclear neurons. Neurons with poorly stained somas, abruptly demarked from intensely stained axons, are numerous and often are arranged in palisades. With prolonged maintenance in vitro these neurons develop some but not all of the features of mature Purkinje cells. A few small, densely stained, bipolar neurons, often with one process bifurcated, are found in dense regions of some cultures of newborn cerebellum. These neurons are commoner in cultures from cerebella of older mice. They closely resemble the immature granule cell in vivo. All the neuron types recognized in cultures are present in the initial explants; neurons differentiate further in vitro, but new neurons probably do not form. Synaptic boutons are found on somas and dendrites of many Purkinje cells. Two cultures contained structures resembling the basket endings which surround Purkinje cell somas in vivo. The complexity of neuronal relationships in cultures of central nervous tissue is emphasized. PMID:14195614

  12. Enhanced dendritic spine number of neurons of the prefrontal cortex, hippocampus and nucleus accumbens in old rats after chronic donepezil administration

    PubMed Central

    Alcantara-Gonzalez, Faviola; Juarez, Ismael; Solis, Oscar; Martinez-Tellez, Isaura; Camacho-Abrego, Israel; Masliah, Eliezer; Mena, Raul; Flores, Gonzalo

    2010-01-01

    In Alzheimer's disease brains morphological changes in the dendrites of pyramidal neurons of the prefrontal cortex (PFC) and hippocampus have been observed. These changes are particularly reflected in the decrement of both the dendritic tree and spine number. Donepezil is a potent and selective acetylcholinesterase inhibitor used in the treatment of Alzheimer's disease. We have studied the effect of oral administration of this drug on the morphology of neuronal cells from the brain of aged rats. We examined dendrites of pyramidal neurons of the PFC, dorsal or ventral hippocampus and medium spiny neurons of the nucleus accumbens (NAcc). Donepezil (1 mg/Kg, vo) was administrated every day for 60 days to rats aged 10 and 18 months. Dendritic morphology was studied by the Golgi-Cox stain procedure followed by Sholl analysis at 12 and 20 months ages, respectively. In all Donepezil treated-rats a significant increment of the dendritic spines number in pyramidal neurons of the PFC, dorsal hippocampus was observed. However, pyramidal neurons of the ventral hippocampus and medium spiny cells of the NAcc only showed an increase in the number of their spines in 12 months old-rats. Our results suggest that Donepezil prevents the alterations of the neuronal dendrite morphology caused by aging. PMID:20336627

  13. The neocortex of cetartiodactyls. II. Neuronal morphology of the visual and motor cortices in the giraffe (Giraffa camelopardalis).

    PubMed

    Jacobs, Bob; Harland, Tessa; Kennedy, Deborah; Schall, Matthew; Wicinski, Bridget; Butti, Camilla; Hof, Patrick R; Sherwood, Chet C; Manger, Paul R

    2015-09-01

    The present quantitative study extends our investigation of cetartiodactyls by exploring the neuronal morphology in the giraffe (Giraffa camelopardalis) neocortex. Here, we investigate giraffe primary visual and motor cortices from perfusion-fixed brains of three subadults stained with a modified rapid Golgi technique. Neurons (n = 244) were quantified on a computer-assisted microscopy system. Qualitatively, the giraffe neocortex contained an array of complex spiny neurons that included both "typical" pyramidal neuron morphology and "atypical" spiny neurons in terms of morphology and/or orientation. In general, the neocortex exhibited a vertical columnar organization of apical dendrites. Although there was no significant quantitative difference in dendritic complexity for pyramidal neurons between primary visual (n = 78) and motor cortices (n = 65), there was a significant difference in dendritic spine density (motor cortex > visual cortex). The morphology of aspiny neurons in giraffes appeared to be similar to that of other eutherian mammals. For cross-species comparison of neuron morphology, giraffe pyramidal neurons were compared to those quantified with the same methodology in African elephants and some cetaceans (e.g., bottlenose dolphin, minke whale, humpback whale). Across species, the giraffe (and cetaceans) exhibited less widely bifurcating apical dendrites compared to elephants. Quantitative dendritic measures revealed that the elephant and humpback whale had more extensive dendrites than giraffes, whereas the minke whale and bottlenose dolphin had less extensive dendritic arbors. Spine measures were highest in the giraffe, perhaps due to the high quality, perfusion fixation. The neuronal morphology in giraffe neocortex is thus generally consistent with what is known about other cetartiodactyls.

  14. Characterization of GABAergic neurons in rapid-eye-movement sleep controlling regions of the brainstem reticular formation in GAD67-green fluorescent protein knock-in mice.

    PubMed

    Brown, Ritchie E; McKenna, James T; Winston, Stuart; Basheer, Radhika; Yanagawa, Yuchio; Thakkar, Mahesh M; McCarley, Robert W

    2008-01-01

    Recent experiments suggest that brainstem GABAergic neurons may control rapid-eye-movement (REM) sleep. However, understanding their pharmacology/physiology has been hindered by difficulty in identification. Here we report that mice expressing green fluorescent protein (GFP) under the control of the GAD67 promoter (GAD67-GFP knock-in mice) exhibit numerous GFP-positive neurons in the central gray and reticular formation, allowing on-line identification in vitro. Small (10-15 microm) or medium-sized (15-25 microm) GFP-positive perikarya surrounded larger serotonergic, noradrenergic, cholinergic and reticular neurons, and > 96% of neurons were double-labeled for GFP and GABA, confirming that GFP-positive neurons are GABAergic. Whole-cell recordings in brainstem regions important for promoting REM sleep [subcoeruleus (SubC) or pontine nucleus oralis (PnO) regions] revealed that GFP-positive neurons were spontaneously active at 3-12 Hz, fired tonically, and possessed a medium-sized depolarizing sag during hyperpolarizing steps. Many neurons also exhibited a small, low-threshold calcium spike. GFP-positive neurons were tested with pharmacological agents known to promote (carbachol) or inhibit (orexin A) REM sleep. SubC GFP-positive neurons were excited by the cholinergic agonist carbachol, whereas those in the PnO were either inhibited or excited. GFP-positive neurons in both areas were excited by orexins/hypocretins. These data are congruent with the hypothesis that carbachol-inhibited GABAergic PnO neurons project to, and inhibit, REM-on SubC reticular neurons during waking, whereas carbachol-excited SubC and PnO GABAergic neurons are involved in silencing locus coeruleus and dorsal raphe aminergic neurons during REM sleep. Orexinergic suppression of REM during waking is probably mediated in part via excitation of acetylcholine-inhibited GABAergic neurons.

  15. Are hemipenial spines related to limb reduction? A spiny discussion focused on gymnophthalmid lizards (Squamata: Gymnophthalmidae).

    PubMed

    Sales Nunes, Pedro M; Curcio, Felipe F; Roscito, Juliana G; Rodrigues, Miguel T

    2014-03-01

    Calcified spines in the hemipenial surface occur convergently in several gymnophthalmid lizard species and in advanced snakes. Based on the pronounced degrees of limb reduction in these distantly related lineages, such hemipenial structures were suggested to play a functional role in couple-anchoring during copulation, partly assuming the function of the limbs during mating. Herein, we assessed the hemipenial morphology of virtually all the valid genera of the family Gymnophthalmidae to test for a phylogenetic correlation between limb reduction and the presence of calcified hemipenial spines. The occurrence of calcified structures was mapped on the two most comprehensive phylogenies of the family. We concluded that spiny hemipenes are by no means necessarily associated with reduction of limbs. Conversely, the presence of well-developed hemipenial spines in specific limb-reduced taxa does not allow one to disregard the possibility that in some instances such structures might indeed be functionally associated with couple-anchoring, improving the success of mating.

  16. Spiny mice (Acomys cahirinus) do not respond to thymus-independent type 2 antigens.

    PubMed

    Pennello, Anthony; Taylor, Justin; Matlack, Robin; Karp, Jonathan; Riggs, James

    2006-01-01

    Analysis of the immune system of spiny mice (Acomys cahirinus) has been limited. Originally grouped with Mus, Acomys has recently been placed closer to Meriones (gerbils). This study compared immunity in Acomys, Mus, and Meriones. Lymphocytes from all rodents examined proliferated in response to mitogen and superantigen stimulation. Only Mus T cells responded to anti-CD3 stimulation. Acomys, like Meriones, and Mus that express xid, did not respond to thymus-independent type 2 antigens. Flow cytometric analyses revealed that T cell-specific MAbs did not bind Acomys or Meriones lymphocytes. The B cell-specific anti-CD45R (B220) MAb detected all rodent B cells and revealed the absence of a CD45R(lo) subset in the peritoneal cavity of Acomys and Meriones. Bone marrow from Acomys and Meriones failed to reconstitute B cell function in SCID mice. Thus, in terms of immunity, Acomys appears to be more similar to Meriones than Mus.

  17. Spiny mouse's (Acomys Cahirinus) use of its distance senses in prey localization.

    PubMed

    Langley, W M

    1988-03-01

    This study examined the relative importance that olfaction, audition and vision played in the spiny mouse's localization of insect prey. These three senses were blocked singly or in various combinations so that a mouse was tested under 8 different situations with a tethered live cricket and four with a dead cricket. The mice did not rely on one particular sense more than the others, but in certain situations olfaction and audition proved more important than vision in the localization of a live cricket. In the case of a stationary cricket, the mice relied more on olfaction than vision. This pattern of use is what would be expected of a nonspecialized omnivore and may represent what ought to be found in many other rodent species.

  18. Neuroprotective properties of melatonin in a model of birth asphyxia in the spiny mouse (Acomys cahirinus).

    PubMed

    Hutton, Lisa C; Abbass, Mahila; Dickinson, Hayley; Ireland, Zoe; Walker, David W

    2009-01-01

    Birth asphyxia is associated with disturbed development of the neonatal brain. In this study, we determined if low-dose melatonin (0.1 mg/kg/day), administered to the mother over 7 days at the end of pregnancy, could protect against the effects of birth asphyxia in a precocial species - the spiny mouse (Acomys cahirinus). At 37 days of gestation (term is 38-39 days), pups were subjected to birth asphyxia (7.5 min uterine ischemia) and compared to Cesarean section-delivered controls. At 24 h of age, birth asphyxia had increased markers of CNS inflammation (microglia, macrophage infiltration) and apoptosis (activated caspase-3, fractin) in cortical gray matter, which were reduced to control levels by prior maternal melatonin treatment. Melatonin may be an effective prophylactic agent for use in late pregnancy to protect against hypoxic-ischemic brain injury at birth.

  19. The structure of the spiny mouse (Acomys cahirinus) ovary during development.

    PubMed

    Hułas, M; Gawron, A

    2002-01-01

    The study presents the structure of the ovaries of the spiny mouse (Acomys cahirinus) during the first months of life. The ovaries in neonate females exhibit a large number of primordial and primary follicles, sometimes clustered in nests. The growing follicles were also observed within the ovary at that period. The first, early antral follicles appeared in the ovary during the second week of life. In the group of 60-day old females, the structure of the ovaries was characterized by a significant increase in the connective tissue elements. Moreover, ovarian follicles at various stages of development were observed, except for the antral ones with cumulus oophorus. The first mature follicles were identified in 3-month old females. In the ovarian follicles, apoptosis occurs at all stages of follicle development, especially in the early antral follicles. In the atretic follicles, apoptotic cells were identified in the layer of granulosa cells.

  20. Milky hemolymph syndrome (MHS) in spiny lobsters, penaeid shrimp and crabs.

    PubMed

    Nunan, Linda M; Poulos, Bonnie T; Navarro, Solangel; Redman, Rita M; Lightner, Donald V

    2010-09-02

    Black tiger shrimp Penaeus monodon, European shore crab Carcinus maenas and spiny lobster Panulirus spp. can be affected by milky hemolymph syndrome (MHS). Four rickettsia-like bacteria (RLB) isolates of MHS originating from 5 geographical areas have been identified to date. The histopathology of the disease was characterized and a multiplex PCR assay was developed for detection of the 4 bacterial isolates. The 16S rRNA gene and 16-23S rRNA intergenic spacer region (ISR) were used to examine the phylogeny of the MHS isolates. Although the pathology of this disease appears similar in the various different hosts, sequencing and examination of the phylogenetic relationships reveal 4 distinct RLB involved in the infection process.

  1. Species identification of spiny lobster phyllosome larvae via ribosomal DNA analysis.

    PubMed

    Silberman, J D; Walsh, P J

    1992-06-01

    Within the tropical northwestern Atlantic, Panulirus argus, P. guttatus, and P. laevicauda (Palinuridae family), are sympatric. Numerous studies have examined the distribution and abundance of planktonic phyllosome larvae with respect to recruitment of spiny lobsters to the benthic population, but the data are of limited use because larvae of these species cannot yet be distinguished from one another by morphological characteristics. A simple molecular method that unambiguously differentiates adults or larvae of P. argus, P. guttatus, and P. laevicauda is described: a 5' region of 28s ribosomal DNA is amplified in vitro and then cut with a diagnostic restriction enzyme to identify each species. Data are also presented from the application of this method to representative plankton tows.

  2. A new species of spiny Solanum (Solanaceae) from Peru

    PubMed Central

    Stern, Stephen R.

    2014-01-01

    Abstract A new species of Solanum is described from Peru. Solanum junctum S. Stern & M. Nee, sp nov. is a member of the Torva clade of the spiny solanums (Leptostemonum clade). The narrow corolla lobes and recurved prickles of Solanum junctum are similar to species in the Micracantha clade, but Solanum junctum differs in its branched inflorescences and upright green fruits. These characteristics are shared with other members the Torva clade; within this section Solanum junctum is morphologically most similar to Solanum subinerme and Solanum poinsettiifolium. Solanum subinerme has larger flowers, longer cauline prickles, and often has long straight prickles on the adaxial leaf surface that are lacking in Solanum junctum. Solanum poinsettiifolium has fewer spines, dense white tomentum on the abaxial leaf surfaces, stout unbranched inflorescences, and more extensive interpetalar corolla tissue than Solanum junctum. PMID:25197223

  3. Some preliminary findings on the nutritional status of the Hawaiian spiny lobster (Panulirus marginatus)

    USGS Publications Warehouse

    Parrish, F.A.; Martinelli-Liedtke, T. L.

    1999-01-01

    Data on the nutritional status of spiny lobster (Panulirus marginatus) were collected on the commercial trapping grounds of Necker Bank, Northwestern Hawaiian Islands, in the summers of 1991, 1994, and 1995. Glycogen levels measured in abdominal tissue of intermolt males were used as an index of nutritional health of the field population. The range of glycogen sampled from wild lobster was less than half the level measured in captive lobster fed to satiation in a previous study. An analysis of covariance identified significant interannual and spatial effects explaining 46% of the variance in the sample of wild lobsters. Most significant was a decline in lobster glycogen levels between samples collected in 1991 and 1994-1995. Seasonal influences on lobster nutrition are unknown and were identified as an obvious direction for future ecological research.

  4. Cloning of sarco-endoplasmic reticulum Ca2+-ATPase (SERCA) from Caribbean spiny lobster Panulirus argus

    PubMed Central

    Arunachalam, S. C.; Meleshkevitch, E. A.; Mandal, P. K.; Boudko, D. Y.; Ahearn, G. A.

    2012-01-01

    We have previously reported on calcium transport mechanisms in American lobster, Homarus americanus, using 45Ca2+ coupled with vesicle preparations of hepatopancreatic endoplasmic reticulum. The active transport of calcium across membranes bordering calcium-sequestering stores such as sarcoplasmic or endoplasmic reticulum is catalyzed by membrane-spanning proteins, the sarco-endoplasmic Ca2+-ATPases (SERCAs). In the study described here we used advanced bioinformatics and molecular techniques to clone SERCA from the economically important Caribbean spiny lobster, Panulirus argus. We report the complete cloning of a full-length SERCA from P. argus antenna cDNA (GenBank accession number AY702617). This cDNA has a 1020-amino acid residue open reading frame which is 90% identical to published sequences of other crustacean SERCA proteins. Our data support the hypothesis that one crustacean and three vertebrate genes controlling calcium transport were derived from a common ancestral gene. PMID:18825387

  5. Intestinal helminths of spiny mice (Acomys cahirinus dimidiatus) from St Katherine's Protectorate in the Sinai, Egypt.

    PubMed

    Behnke, J M; Barnard, C J; Mason, N; Harris, P D; Sherif, N E; Zalat, S; Gilbert, F S

    2000-03-01

    Spiny mice, Acomys cahirinus dimidiatus, inhabiting the wadis close to St Katherine in the mountains of the Sinai peninsula, were trapped and their helminth parasites were studied. Sixty one mice provided faeces for analysis and 27 were killed and autopsied. Six species of helminths were recorded (the spirurid nematodes, Protospirura muricola (74.1%) and Mastophorus muris (11.1%), the oxyuroid nematodes, Dentostomella kuntzi (59.3%), Aspiculuris africana (3.7%), and Syphacia minuta (3.7%) and the hymenolepidid cestode Rodentolepis negevi (18.5%)). The spirurids were the dominant species present, accounting for up to 0.87% of total host body weight. Analysis of worm weights and lengths suggested that transmission had been taking place in the months preceding our study. No sex difference in the prevalence or abundance of spirurids was detected. Significant differences were identified in the abundance of total nematode burdens and the mean helminth species richness between the three wadis which provided multiple captures of mice. There was also a marked effect of host age on both parameters. A highly significant positive correlation between spirurid egg counts and total worm biomass indicated that non-invasive techniques based on egg counts could be used to quantify worm burdens and when this technique was applied to a larger sample size (n = 61), a significant difference between sites but no host sex or age effects were detected for spirurid faecal egg counts. The data suggest that there are differences between helminth component communities infecting spiny mice in different neighbouring wadis, a hypothesis which will be explored further through our continuing studies in the Sinai.

  6. Sympatric incipient speciation of spiny mice Acomys at “Evolution Canyon,” Israel

    PubMed Central

    Hadid, Yarin; Pavlíček, Tomáš; Beiles, Avigdor; Ianovici, Ron; Raz, Shmuel; Nevo, Eviatar

    2014-01-01

    Does the paucity of empirical evidence of sympatric speciation in nature reflect reality, despite theoretical support? Or is it due to inappropriate searches in nature with overly restrictive assumptions and an incorrect null hypothesis? Spiny mice, Acomys, described here at Evolution Canyon (EC) incipiently and sympatrically speciate owing to microclimatic interslope divergence. The opposite slopes at EC vary dramatically, physically and biotically, representing the dry and hot south-facing slope savannoid-African continent [“African” slope (AS)], abutting with the north-facing slope forested south-European continent [“European” slope (ES)]. African-originated spiny mice, of the Acomys cahirinus complex, colonized Israel 30,000 y ago based on fossils. Genotypically, we showed significantly higher genetic diversity of mtDNA and amplified fragment length polymorphism of Acomys on the AS compared with the ES. This is also true regionally across Israel. In complete mtDNA, 25% of the haplotypes at EC were slope-biased. Phenotypically, the opposite slope’s populations also showed adaptive morphology, physiology, and behavior divergence paralleling regional populations across Israel. Preliminary tests indicate slope-specific mate choices. Colonization of Acomys at the EC first occurred on the AS and then moved to the ES. Strong slope-specific natural selection (both positive and negative) overrules low interslope gene flow. Both habitat slope selection and mate choices suggest ongoing incipient sympatric speciation. We conclude that Acomys at the EC is ecologically and genetically adaptively, incipiently, sympatrically speciating on the ES owing to adaptive microclimatic natural selection. PMID:24402169

  7. Cell and molecular biology of SAE, a cell line from the spiny dogfish shark, Squalus acanthias.

    PubMed

    Parton, Angela; Forest, David; Kobayashi, Hiroshi; Dowell, Lori; Bayne, Christopher; Barnes, David

    2007-02-01

    Cartilaginous fish, primarily sharks, rays and skates (elasmobranchs), appeared 450 million years ago. They are the most primitive vertebrates, exhibiting jaws and teeth, adaptive immunity, a pressurized circulatory system, thymus, spleen, and a liver comparable to that of humans. The most used elasmobranch in biomedical research is the spiny dogfish shark, Squalus acanthias. Comparative genomic analysis of the dogfish shark, the little skate (Leucoraja erincea), and other elasmobranchs have yielded insights into conserved functional domains of genes associated with human liver function, multidrug resistance, cystic fibrosis, and other biomedically relevant processes. While genomic information from these animals is informative in an evolutionary framework, experimental verification of functions of genomic sequences depends heavily on cell culture approaches. We have derived the first multipassage, continuously proliferating cell line of a cartilaginous fish. The line was initiated from embryos of the spiny dogfish shark. The cells were maintained in a medium modified for fish species and supplemented with cell type-specific hormones, other proteins and sera, and plated on a collagen substrate. SAE cells have been cultured continuously for three years. These cells can be transfected by plasmids and have been cryopreserved. Expressed Sequence Tags generated from a normalized SAE cDNA library included a number of markers for cartilage and muscle, as well as proteins influencing tissue differentiation and development, suggesting that SAE cells may be of mesenchymal stem cell origin. Examination of SAE EST sequences also revealed a cartilaginous fish-specific repetitive sequence that may be evidence of an ancient mobile genetic element that most likely was introduced into the cartilaginous fish lineage after divergence from the lineage leading to teleosts.

  8. Flow through the nasal cavity of the spiny dogfish, Squalus acanthias

    NASA Astrophysics Data System (ADS)

    Timm-Davis, L. L.; Fish, F. E.

    2015-12-01

    The nasal cavity of spiny dogfish is a blind capsule with no internal connection to the oral cavity. Water is envisioned to flow through the cavity in a smooth, continuous flow pattern; however, this assumption is based on previous descriptions of the morphology of the olfactory cavity. No experimentation on the flow through the internal nasal cavity has been reported. Morphology of the head of the spiny dogfish ( Squalus acanthias) does not suggest a close external connection between the oral and nasal systems. However, dye visualization showed that there was flow through the nasal apparatus and from the excurrent nostril to the mouth when respiratory flows were simulated. The hydrodynamic flow through the nasal cavity was observed from flow tank experiments. The dorsum of the nasal cavity of shark heads from dead animals was exposed by dissection and a glass plate was glued over of the exposed cavity. When the head was placed in a flow, dye was observed to be drawn passively into the cavity showing a complex, three-dimensional hydrodynamic flow. Dye entered the incurrent nostril, flowed through the nasal lamellae, crossed over and under the nasal valve, and circulated around the nasal valve before exiting the excurrent nostril. When the nasal valve was removed, the dye became stagnant and back flowed out through the incurrent nostril. The single nasal valve has a hydrodynamic function that organizes a coherent flow of water through the cavity without disruption. The results suggest that the morphology of the nasal apparatus in concert with respiratory flow and ambient flows from active swimming can be used to draw water through the olfactory cavity of the shark.

  9. Physiological effects of waterborne lead exposure in spiny dogfish (Squalus acanthias).

    PubMed

    Eyckmans, Marleen; Lardon, Isabelle; Wood, Chris M; De Boeck, Gudrun

    2013-01-15

    To broaden our knowledge about the toxicity of metals in marine elasmobranchs, cannulated spiny dogfish (Squalus acanthias) were exposed to 20 μM and 100 μM lead (Pb). Since we wanted to focus on sub lethal ion-osmoregulatory and respiratory disturbances, arterial blood samples were analysed for pH(a), PaO(2), haematocrit and total CO(2) values at several time points. Plasma was used to determine urea, TMAO, lactate and ion concentrations. After 96 h, Pb concentrations were determined in a number of tissues, such as gill, rectal gland, skin and liver. To further investigate ion and osmoregulation, Na(+)/K(+)-ATPase activities in gill and rectal gland were analysed as well as rates of ammonia and urea excretion. Additionally, we studied the energy reserves in muscle and liver. Pb strongly accumulated in gills and especially in skin. Lower accumulation rates occurred in gut, kidney and rectal gland. A clear disturbance in acid-base status was observed after one day of exposure indicating a transient period of hyperventilation. The increase in pH(a) was temporary at 20 μM, but persisted at 100 μM. After 2 days, plasma Na and Cl concentrations were reduced compared to controls at 100 μM Pb and urea excretion rates were elevated. Pb caused impaired Na(+)/K(+)-ATPase activity in gills, but not in rectal gland. We conclude that spiny dogfish experienced relatively low ion-osmoregulatory and respiratory distress when exposed to lead, particularly when compared to effects of other metals such as silver. These elasmobranchs appear to be able to minimize the disturbance and maintain physiological homeostasis during an acute Pb exposure.

  10. Temperature dependent growth, feeding, nutritional condition and aerobic metabolism of juvenile spiny lobster, Sagmariasus verreauxi.

    PubMed

    Fitzgibbon, Quinn P; Simon, Cedric J; Smith, Gregory G; Carter, Chris G; Battaglene, Stephen C

    2017-05-01

    We examined the effects of temperature on the growth, feeding, nutritional condition and aerobic metabolism of juvenile spiny lobster, Sagmariasus verreauxi, in order to determine if temperature acclimated aerobic scope correlates with optimum for growth and to establish the thermal tolerance window for this emerging aquaculture species. Juvenile lobsters (initial weight=10.95±0.47g) were reared (n=7) at temperatures from 11.0 to 28.5°C for 145days. All lobsters survived from 14.5 to 25.0°C while survival was reduced at 11.0°C (86%) and all lobsters died at 28.5°C. Lobster specific growth rate and specific feed consumption displayed a unimodal response with temperature, peaking at 21.5°C. Lobster standard, routine and maximum metabolic rates, and aerobic scope all increased exponentially up to maximum non-lethal temperature. Optimum temperature for growth did not correspond to that for maximum aerobic scope suggesting that aerobic scope is not an effective predictor of the thermal optimum of spiny lobsters. Plateauing of specific feed consumption beyond 21.5°C suggests that temperature dependent growth of lobsters is limited by capacity to ingest or digest sufficient food to meet increasing maintenance metabolic demands at high temperatures. The nutritional condition of lobsters was not influenced by temperature and feed conversion ratio was improved at lower temperatures. These findings add to a growing body of evidence questioning the generality of aerobic scope to describe the physiological thermal boundaries of aquatic ectotherms and suggest that feed intake plays a crucial role in regulating performance at thermal extremes.

  11. Prenatal cerebral ischemia triggers dysmaturation of caudate projection neurons

    PubMed Central

    McClendon, Evelyn; Chen, Kevin; Gong, Xi; Sharifnia, Elica; Hagen, Matthew; Cai, Victor; Shaver, Daniel C.; Riddle, Art; Dean, Justin M.; Gunn, Alistair J.; Mohr, Claudia; Kaplan, Joshua S.; Rossi, David J.; Kroenke, Christopher D.; Hohimer, A. Roger; Back, Stephen A.

    2014-01-01

    Objective Recently we reported that the neocortex displays impaired growth after transient cerebral hypoxia-ischemia (HI) at preterm gestation that is unrelated to neuronal death but is associated with decreased dendritic arbor complexity of cortical projection neurons. We hypothesized that these morphological changes constituted part of a more widespread neuronal dysmaturation response to HI in the caudate nucleus (CN), which contributes to motor and cognitive disability in preterm survivors. Methods Ex vivo magnetic resonance imaging (MRI), immunohistochemistry and Golgi staining defined CN growth, cell death, proliferation and dendritic maturation in preterm fetal sheep four weeks after HI. Patch-clamping recording was used to analyze glutamatergic synaptic currents in CN neurons. Results MRI-defined growth of the CN was reduced after ischemia compared to controls. However, no significant acute or delayed neuronal death was seen in the CN or white matter. Neither was there significant loss of calbindin-positive medium spiny projection neurons (MSNs) or CN interneurons expressing somatostatin, calretinin, parvalbumin, or tyrosine hydroxylase. Morphologically, ischemic MSNs showed a markedly immature dendritic arbor, with fewer dendritic branches, nodes, endings and spines. The magnitude and kinetics of synaptic currents, and the relative contribution of glutamate receptor subtypes in the CN were significantly altered. Interpretation The marked MSN dendritic and functional abnormalities after preterm cerebral HI, despite the marked resistance of immature CN neurons to cell death, are consistent with widespread susceptibility of projection neurons to HI-induced dysmaturation. These global disturbances in dendritic maturation and glutamatergic synaptic transmission suggest a new mechanism for long-term motor and behavioral disabilities in preterm survivors via widespread disruption of neuronal connectivity. PMID:24395459

  12. Topographical distribution and morphology of NADPH-diaphorase-stained neurons in the human claustrum.

    PubMed

    Hinova-Palova, Dimka V; Edelstein, Lawrence; Landzhov, Boycho; Minkov, Minko; Malinova, Lina; Hristov, Stanislav; Denaro, Frank J; Alexandrov, Alexandar; Kiriakova, Teodora; Brainova, Ilina; Paloff, Adrian; Ovtscharoff, Wladimir

    2014-01-01

    We studied the topographical distribution and morphological characteristics of NADPH-diaphorase-positive neurons and fibers in the human claustrum. These neurons were seen to be heterogeneously distributed throughout the claustrum. Taking into account the size and shape of stained perikarya as well as dendritic and axonal characteristics, Nicotinamide adenine dinucleotide phosphate-diaphorase (NADPHd)-positive neurons were categorized by diameter into three types: large, medium and small. Large neurons ranged from 25 to 35 μm in diameter and typically displayed elliptical or multipolar cell bodies. Medium neurons ranged from 20 to 25 μm in diameter and displayed multipolar, bipolar and irregular cell bodies. Small neurons ranged from 14 to 20 μm in diameter and most often displayed oval or elliptical cell bodies. Based on dendritic characteristics, these neurons were divided into spiny and aspiny subtypes. Our findings reveal two populations of NADPHd-positive neurons in the human claustrum-one comprised of large and medium cells consistent with a projection neuron phenotype, the other represented by small cells resembling the interneuron phenotype as defined by previous Golgi impregnation studies.

  13. Hippocampal neuronal subtypes develop abnormal dendritic arbors in the presence of Fragile X astrocytes.

    PubMed

    Jacobs, S; Cheng, C; Doering, L C

    2016-06-02

    Astrocytes are now recognized as key players in the neurobiology of neurodevelopmental disorders such as Fragile X syndrome. However, the nature of Fragile X astrocyte-mediated control of dendrite development in subtypes of hippocampal neurons is not yet known. We used a co-culture procedure in which wildtype primary hippocampal neurons were cultured with astrocytes from either a wildtype or Fragile X mouse, for either 7, 14 or 21 days. The neurons were processed for immunocytochemistry with the dendritic marker MAP2, classified by morphological criteria into one of five neuronal subtypes, and subjected to Sholl analyses. Both linear and semi-log methods of Sholl analyses were applied to the neurons in order to provide an in depth analysis of the dendritic arborizations. We found that Fragile X astrocytes affect the development of dendritic arborization of all subtypes of wildtype hippocampal neurons. Furthermore, we show that hippocampal neurons with spiny stellate neuron morphology exhibit the most pervasive developmental delays, with significant dendritic arbor alterations persisting at 21 days in culture. The results further dictate the critical role astrocytes play in governing neuronal morphology including altered dendrite development in Fragile X.

  14. mGluR5 Exerts Cell-Autonomous Influences on the Functional and Anatomical Development of Layer IV Cortical Neurons in the Mouse Primary Somatosensory Cortex

    PubMed Central

    Ballester-Rosado, Carlos J.; Sun, Hao; Huang, Jui-Yen

    2016-01-01

    Glutamate neurotransmission refines synaptic connections to establish the precise neural circuits underlying sensory processing. Deleting metabotropic glutamate receptor 5 (mGluR5) in mice perturbs cortical somatosensory map formation in the primary somatosensory (S1) cortex at both functional and anatomical levels. To examine the cell-autonomous influences of mGluR5 signaling in the morphological and functional development of layer IV spiny stellate glutamatergic neurons receiving sensory input, mGluR5 genetic mosaic mice were generated through in utero electroporation. In the S1 cortex of these mosaic brains, we found that most wild-type neurons were located in barrel rings encircling thalamocortical axon (TCA) clusters while mGluR5 knock-out (KO) neurons were placed in the septal area, the cell-sparse region separating barrels. These KO neurons often displayed a symmetrical dendritic morphology with increased dendritic complexity, in contrast to the polarized pattern of wild-type neurons. The dendritic spine density of mGluR5 KO spiny stellate neurons was significantly higher than in wild-type neurons. Whole-cell electrophysiological recordings detected a significant increase in the frequencies of spontaneous and miniature excitatory postsynaptic events in mGluR5 KO neurons compared with neighboring wild-type neurons. Our mosaic analysis provides strong evidence supporting the cell-autonomous influence of mGluR5 signaling on the functional and anatomical development of cortical glutamatergic neurons. Specifically, mGluR5 is required in cortical glutamatergic neurons for the following processes: (1) the placement of cortical glutamatergic neurons close to TCA clusters; (2) the regulation of dendritic complexity and outgrowth toward TCA clusters; (3) spinogenesis; and (4) tuning of excitatory inputs. SIGNIFICANCE STATEMENT Glutamatergic transmission plays a critical role in cortical circuit formation. Its dysfunction has been proposed as a core factor in the

  15. Reproductive Female Feeding Strategies in Spiny Forest-Dwelling Lemur catta in Southern and Southwestern Madagascar: How Do Females Meet the Challenges of Reproduction in this Harsh Habitat?

    PubMed

    Gould, Lisa; Kelley, Elizabeth A; LaFleur, Marni

    2015-01-01

    The spiny forest ecoregion of southern and southwestern Madagascar is characterized by low annual rainfall, high temperatures, short-stature xeric vegetation and lack of canopy. Lemur catta is often the only diurnal primate persisting in this habitat. For reproductive females living in spiny forests, gestation and early-to-mid lactation periods occur during the dry season when food resources are limited. We conducted a between-site comparison of variables important to the feeding ecology of reproductive female L. catta inhabiting spiny forest at 3 sites: Berenty spiny forest (BSF), Cap Sainte-Marie (CSM) and Tsimanampesotse National Park (TNP). We hypothesize that the ability for pregnant and lactating females to adequately obtain plant foods high in protein, low in fiber and with a high water content is crucial to their survival and successful reproduction in spiny habitat. We found favorable or relatively equal protein-to-fiber ratios in plant foods most frequently consumed by reproductive females, and preferred foods contained high water content. Some overlap in preferred plant species at the 3 sites suggests important plant foods for reproductive females inhabiting spiny forests. We suggest that choosing foods high in protein, relatively low in fiber and with high water content are behavioral adaptations allowing female L. catta to reproduce and survive in this habitat.

  16. Mitochondrial fragmentation in neuronal degeneration: Toward an understanding of HD striatal susceptibility.

    PubMed

    Cherubini, Marta; Ginés, Silvia

    2017-02-19

    Huntington's disease (HD) is an autosomal-dominant progressive neurodegenerative disorder that primarily affects medium spiny neurons within the striatum. HD is caused by inheritance of an expanded CAG repeat in the HTT gene, resulting in a mutant huntingtin (mHtt) protein containing extra glutamine residues. Despite the advances in understanding the molecular mechanisms involved in HD the preferential vulnerability of the striatum remains an intriguing question. This review discusses current knowledge that links altered mitochondrial dynamics with striatal susceptibility in HD. We also highlight how the modulation of mitochondrial function may constitute an attractive therapeutic approach to reduce mHtt-induced toxicity and therefore prevent the selective striatal neurodegeneration.

  17. The neuronal structure of globus pallidus in bison bonasus: Nissl and Golgi study.

    PubMed

    Rowniak, M; Szteyn, S; Robak, A

    1995-01-01

    The two subnuclei of globus pallidus have been investigated in the telencephalon of bison bonasus. The Nissl and Golgi procedures have been used to reveal their cellular organization. The Golgi preparation suggests the existence of two fairly divergent cellular subpopulations. The first class comprising the bulk of pallidal neurons consists of large efferent cells with long thick infrequently branching dendrites. The morphology of their dendritic processes is very complex and variable even in the one neuron (complex terminal endings, thin dendritic appendages, spiny segments, aspiny segments). Some of these structures (i.e. terminal endings, thin appendages) seem to be of presynaptic nature and allow one efferent neuron to influence on the functions of other large pallidal cells (interneuronal functions). The second one is composed of small interneurons with short highly arborized axons and thin varicose dendritic processes. Their distribution is very sparse and irregular in both segments of investigated nucleus.

  18. Spiny lobsters use urine-borne olfactory signaling and physical aggressive behaviors to influence social status of conspecifics.

    PubMed

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

    2009-08-01

    Decapod crustaceans, like many other animals, engage in agonistic behaviors that enhance their ability to compete for resources with conspecifics. These agonistic behaviors include the release of chemical signals as well as physical aggressive and submissive behaviors. In this study, we report that Caribbean spiny lobsters, Panulirus argus, use both urine-borne chemical signaling and physical aggressive behaviors during interactions with conspecifics, and that these agonistic behaviors can influence the behavior and eventual social status of the interactants. Spiny lobsters that engaged primarily in physical aggressive behaviors became dominant, whereas spiny lobsters that received these physical aggressive behaviors responded with avoidance behaviors and became subordinates. Dominant animals frequently released urine during social interactions, more than when they were not in contact with subordinates and more than when they were not paired with another animal. Subordinates released urine significantly less often than dominants, and no more than when not paired. Preventing release of urine by catheterizing the animals resulted in an increase in the number and duration of physical interactions, and this increase was primarily driven by dominants initiating interactions through physical aggressive behaviors. Introducing urine from one of the catheterized animals into an aquarium reduced physical aggressive behavior by dominant animals to normal levels. Urine-borne signals alone were capable of inducing avoidance behaviors from solitary spiny lobsters in both laboratory and field conditions. We conclude that urine serves as a chemical signal that communicates social status to the interactants. Ablation experiments showed that that these urine signals are detected primarily by aesthetasc sensilla of the olfactory pathway.

  19. Anatomy and muscle activity of the dorsal fins in bamboo sharks and spiny dogfish during turning maneuvers.

    PubMed

    Maia, Anabela; Wilga, Cheryl D

    2013-11-01

    Stability and procured instability characterize two opposing types of swimming, steady and maneuvering, respectively. Fins can be used to manipulate flow to adjust stability during swimming maneuvers either actively using muscle control or passively by structural control. The function of the dorsal fins during turning maneuvering in two shark species with different swimming modes is investigated here using musculoskeletal anatomy and muscle function. White-spotted bamboo sharks are a benthic species that inhabits complex reef habitats and thus have high requirements for maneuverability. Spiny dogfish occupy a variety of coastal and continental shelf habitats and spend relatively more time cruising in open water. These species differ in dorsal fin morphology and fin position along the body. Bamboo sharks have a larger second dorsal fin area and proportionally more muscle insertion into both dorsal fins. The basal and radial pterygiophores are plate-like structures in spiny dogfish and are nearly indistinguishable from one another. In contrast, bamboo sharks lack basal pterygiophores, while the radial pterygiophores form two rows of elongated rectangular elements that articulate with one another. The dorsal fin muscles are composed of a large muscle mass that extends over the ceratotrichia overlying the radials in spiny dogfish. However, in bamboo sharks, the muscle mass is divided into multiple distinct muscles that insert onto the ceratotrichia. During turning maneuvers, the dorsal fin muscles are active in both species with no differences in onset between fin sides. Spiny dogfish have longer burst durations on the outer fin side, which is consistent with opposing resistance to the medium. In bamboo sharks, bilateral activation of the dorsal in muscles could also be stiffening the fin throughout the turn. Thus, dogfish sharks passively stiffen the dorsal fin structurally and functionally, while bamboo sharks have more flexible dorsal fins, which result from a

  20. Globus Pallidus Externus Neurons Expressing parvalbumin Interconnect the Subthalamic Nucleus and Striatal Interneurons

    PubMed Central

    Saunders, Arpiar; Huang, Kee Wui; Sabatini, Bernardo Luis

    2016-01-01

    The globus pallidus externus (GP) is a nucleus of the basal ganglia (BG), containing GABAergic projection neurons that arborize widely throughout the BG, thalamus and cortex. Ongoing work seeks to map axonal projection patterns from GP cell types, as defined by their electrophysiological and molecular properties. Here we use transgenic mice and recombinant viruses to characterize parvalbumin expressing (PV+) GP neurons within the BG circuit. We confirm that PV+ neurons 1) make up ~40% of the GP neurons 2) exhibit fast-firing spontaneous activity and 3) provide the major axonal arborization to the STN and substantia nigra reticulata/compacta (SNr/c). PV+ neurons also innervate the striatum. Retrograde labeling identifies ~17% of pallidostriatal neurons as PV+, at least a subset of which also innervate the STN and SNr. Optogenetic experiments in acute brain slices demonstrate that the PV+ pallidostriatal axons make potent inhibitory synapses on low threshold spiking (LTS) and fast-spiking interneurons (FS) in the striatum, but rarely on spiny projection neurons (SPNs). Thus PV+ GP neurons are synaptically positioned to directly coordinate activity between BG input nuclei, the striatum and STN, and thalamic-output from the SNr. PMID:26905595

  1. Basic ecology of the Oaxacan Spiny-tailed Iguana Ctenosaura oaxacana (Squamata: Iguanidae), in Oaxaca, Mexico.

    PubMed

    Rioja, Tamara; Carrillo-Reyes, Arturo; Espinoza-Medinilla, Eduardo; López-Mendoza, Sergio

    2012-12-01

    The Oaxacan Spiny-tailed Iguana Ctenosaura oaxacana is a restricted species to the Isthmus of Tehuantepec in Southern Oaxaca, Mexico. This reptile is one of the less known iguanid species. We census-tracked a population in the South ofNiltepec, Oaxaca, Mexico from May 2010 to April 2011. Throughout one year, a total of 10 line transects were situated and recorded in the study area to determine relative abundance and density, and habitat type use (dry forest, Nanchal, grassland, riparian vegetation, and mangrove) by the species. This study reports a new C. oaxacana population on the Southeastern limit of species range. Although this species has a very restricted distribution and is in danger of extinction, C. oaxacana has a high population density when compared to other Ctenosaura species. A total of 108 individuals were recorded throughout the study. Dry forest (33.75ind/ha) and Nanchal (18.75ind/ha) were the habitats with higher densities. Comparisons between habitat types showed no significant differences between dry forest and Nanchal (W=15, p=0.0808). Results between seasons were similar. The Oaxacan Spiny tailed Iguana preferred first the dry forest, and then Nanchal, while avoided grassland, riparian vegetation, and mangroves. There was no difference in habitat use between males and females. Mean perch heights were 1.23 +/- 0.32 (n=30) in Nanchal, 2.11 +/- 0.30 (n=9) in grassland, 1.90 +/- 0.56 (n=54) in dry forest, 1.91 +/- 0.28 (n=9) in mangrove and 2.30 +/- 0.37 (n=6) in riparian vegetation. Species observed as refuge and perch were B. crassifolia (Nanchal); C. alata (grassland); Tabebuia sp., Genipa americana, G. sepium, Acacia sp., Ficus sp. and Haematoxylon sp. (dry forest); G. sepium, Acacia sp. and Guazuma ulmifolia (riparian vegetation); and C. erecta (mangrove). Live trees hollows and branches were used by species. Main threats to the species are excessive hunting and habitat loss. Furthermore, grassland fires are still common in the study area

  2. Effect of food availability and leptin on the physiology and hypothalamic gene expression of the golden spiny mouse: a desert rodent that does not hoard food.

    PubMed

    Gutman, Roee; Hacmon-Keren, Ronit; Choshniak, Itzhak; Kronfeld-Schor, Noga

    2008-12-01

    Food availability and quality in desert habitats are spatially and temporally unpredictable, and animals face periods of food shortage. The golden spiny mouse (Acomys russatus) is an omnivorous desert rodent that does not hoard food, requiring it to withstand such periods by physiological means alone. In response to food restriction, plasma leptin concentrations, core body temperature, and energy expenditure of the spiny mouse decrease significantly after 24 h, and most spiny mice are able to maintain their body mass to approximately 85% of ad libitum for a prolonged period of time. Both 1-day food deprivation and long-term food restriction had a significant effect on body mass and plasma leptin concentrations, which decreased significantly with a high correlation, as well as on the orexigenic agouti-related protein, which increased significantly as a result of the 24-h food deprivation; and on neuropeptide Y (NPY), in which the increase was more pronounced under long-term food restriction. Food restriction and food deprivation had no effect, however, on the anorexigenic pro-opiomelanocortin and cocaine and amphetamine-related transcript. Leptin administration to food-restricted spiny mice did not affect food intake or the rate of decrease in body mass, indicating that it cannot overcome the drive to eat when food is scarce. However, it did result in a significant decrease in NPY levels, and the spiny mice spent less time at low body temperatures compared with PBS-treated golden spiny mice. These results show that in food-restricted golden spiny mice, leptin affects thermogenesis, but not food consumption, and suggest that the thermoregulatory effects of leptin are mediated by NPY.

  3. Distribution and Intrinsic Membrane Properties of Basal Forebrain GABAergic and Parvalbumin Neurons in the Mouse

    PubMed Central

    McKenna, James T.; Yang, Chun; Franciosi, Serena; Winston, Stuart; Abarr, Kathleen K.; Rigby, Matthew S.; Yanagawa, Yuchio; McCarley, Robert W.; Brown, Ritchie E.

    2013-01-01

    The basal forebrain (BF) strongly regulates cortical activation, sleep homeostasis, and attention. Many BF neurons involved in these processes are GABAergic, including a subpopulation of projection neurons containing the calcium-binding protein, parvalbumin (PV). However, technical difficulties in identification have prevented a precise mapping of the distribution of GABAergic and GABA/PV+ neurons in the mouse or a determination of their intrinsic membrane properties. Here we used mice expressing fluorescent proteins in GABAergic (GAD67-GFP knock-in mice) or PV+ neurons (PV-Tomato mice) to study these neurons. Immunohistochemical staining for GABA in GAD67-GFP mice confirmed that GFP selectively labeled BF GABAergic neurons. GFP+ neurons and fibers were distributed throughout the BF, with the highest density in the magnocellular preoptic area (MCPO). Immunohistochemistry for PV indicated that the majority of PV+ neurons in the BF were large (>20 μm) or medium-sized (15–20 μm) GFP+ neurons. Most medium and large-sized BF GFP+ neurons, including those retrogradely labeled from the neocortex, were fast-firing and spontaneously active in vitro. They exhibited prominent hyperpolarization-activated inward currents and subthreshold “spikelets,” suggestive of electrical coupling. PV+ neurons recorded in PV-Tomato mice had similar properties but had significantly narrower action potentials and a higher maximal firing frequency. Another population of smaller GFP+ neurons had properties similar to striatal projection neurons. The fast firing and electrical coupling of BF GABA/PV+ neurons, together with their projections to cortical interneurons and the thalamic reticular nucleus, suggest a strong and synchronous control of the neocortical fast rhythms typical of wakefulness and REM sleep. PMID:23254904

  4. Phylogeny and tempo of diversification in the superradiation of spiny-rayed fishes

    PubMed Central

    Near, Thomas J.; Dornburg, Alex; Eytan, Ron I.; Keck, Benjamin P.; Smith, W. Leo; Kuhn, Kristen L.; Moore, Jon A.; Price, Samantha A.; Burbrink, Frank T.; Friedman, Matt; Wainwright, Peter C.

    2013-01-01

    Spiny-rayed fishes, or acanthomorphs, comprise nearly one-third of all living vertebrates. Despite their dominant role in aquatic ecosystems, the evolutionary history and tempo of acanthomorph diversification is poorly understood. We investigate the pattern of lineage diversification in acanthomorphs by using a well-resolved time-calibrated phylogeny inferred from a nuclear gene supermatrix that includes 520 acanthomorph species and 37 fossil age constraints. This phylogeny provides resolution for what has been classically referred to as the “bush at the top” of the teleost tree, and indicates acanthomorphs originated in the Early Cretaceous. Paleontological evidence suggests acanthomorphs exhibit a pulse of morphological diversification following the end Cretaceous mass extinction; however, the role of this event on the accumulation of living acanthomorph diversity remains unclear. Lineage diversification rates through time exhibit no shifts associated with the end Cretaceous mass extinction, but there is a global decrease in lineage diversification rates 50 Ma that occurs during a period when morphological disparity among fossil acanthomorphs increases sharply. Analysis of clade-specific shifts in diversification rates reveal that the hyperdiversity of living acanthomorphs is highlighted by several rapidly radiating lineages including tunas, gobies, blennies, snailfishes, and Afro-American cichlids. These lineages with high diversification rates are not associated with a single habitat type, such as coral reefs, indicating there is no single explanation for the success of acanthomorphs, as exceptional bouts of diversification have occurred across a wide array of marine and freshwater habitats. PMID:23858462

  5. Temporal segregation in coexisting spiny mice (genus Acomys): role of photoperiod and heterospecific odor.

    PubMed

    Friedman, D; Haim, A; Zisapel, N

    1997-08-01

    Daily rhythms of activity and body temperature were measured in golden spiny mice Acomys russatus, acclimated for 2 weeks, at least, to 2 different photoperiod regimes (16L:8D; 8L:16D) at a constant ambient temperature of 28 degrees C. For recording body temperature, VM-FM (Mini-Mitter Co. Inc., Sunriver, OR) transmitters were implanted. For activity measurements, an infrared sensor (Hengstar BL 68 907F, Japan, using a Lodestar PS-303 power supply, Taiwan) mounted on each cage. Both rhythms were also measured in the same individuals exposed to chemical signals released in the urine of A. cahirinus. The results of this study show that both rhythms of A. russatus correlate and respond to changes in photoperiod regimens, as well as to the chemical signals. However, the correlation changes under the 2 photoperiod regimens. Under LD acclimation, a decrease in the correlation is noted, as a response to the addition of chemical signals. Our results suggest that the different responses due to the different light regimens represent 2 seasons in nature, where presumably each season demands a different physiological response.

  6. Gastrointestinal nematode community of spiny mice (Acomys dimidiatus) from St. Katherine, South Sinai, Egypt.

    PubMed

    Soliman, Maha F M; Ibrahim, Mohamed M; Zalat, Samy M

    2015-12-01

    The objective of this work was to study gastrointestinal nematode community infecting Acomys dimidiatus in different wadis of St. Katherine, South Sinai, Egypt. Fieldwork was conducted in three Wadis over a 4 weeks period during April-May, 2003 in St. Katherine, South Sinai, Egypt. Faecal samples from 47 spiny mice were analysed for gastrointestinal nematode community. The nematodes community consisted of four genera Dentostomella spp., Syphacia spp., Aspicularis spp. and Spirurids species. The overall prevalence of infection was 55.3 %. A significant difference in prevalence was found per wadis. Wadi Toffaha showed the highest diversity when compared to other Wadis. Mean species richness was higher in Wadi Tlah (0.87) when compared to other Wadis. Syphacia spp. was frequently found coexisting with other nematodes. A significant interaction was found between both site and co-infection for Aspicularis spp. The spatial stability of nematode community was discussed compared to other related studies. In terms of similarity, the nematode community from Wadi Toffaha was closest to Wadi Tlah. In conclusion, this study showed that there is spatial variation in the distribution of nematode community. Possible factors affecting the stability of parasite community were discussed and further studies are needed.

  7. Differential energy costs of winter acclimatized common spiny mice Acomys cahirinus from two adjacent habitats.

    PubMed

    Scantlebury, Michael; Shanas, Uri; Kupshtein, Hagai; Speakman, John R; Haim, Abraham

    2004-02-01

    The common spiny mouse Acomys cahirinus, of Ethiopian origin, has a widespread distribution across arid, semi-arid and Mediterranean parts of the Arabian sub-region. We compared the daily energy expenditure (DEE), water turnover (WTO) and sustained metabolic scope (SusMS=DEE/resting metabolic rate) of two adjacent populations during the winter. Mice were captured from North- and South- facing slopes (NFS and SFS) of the same valley, comprising mesic and xeric habitats, respectively. Both DEE and SusMS winter values were greater in NFS than SFS mice and were significantly greater than values previously measured in the summer for these two populations in the same environments. However, WTO values were consistent with previously established values and were not significantly different from allometric predictions for desert eutherians. We suggest that physiological plasticity in energy expenditure, which exists both temporally and spatially, combined with stable WTO, perhaps reflecting a xeric ancestry, has enabled A. cahirinus to invade a wide range of habitats.

  8. Evolutionary Divergence of Geographic Subspecies within the Scalloped Spiny Lobster Panulirus homarus (Linnaeus 1758)

    PubMed Central

    Lavery, Shane D.; Farhadi, Ahmad; Farahmand, Hamid; Chan, Tin-Yam; Azhdehakoshpour, Ashkan; Thakur, Vibhavari; Jeffs, Andrew G.

    2014-01-01

    Panulirus homarus is an economically important spiny lobster that is widespread through the Indo-West Pacific Region, but has an uncertain taxonomic status, with three or four geographic subspecies having been described. This study used mitochondrial (16S, COI and control region) and nuclear (18S, ITS-1) DNA sequences to examine specimens of all putative subspecies and forms from throughout their range, in order to determine their genetic validity, and understand the evolutionary history of this species. Despite the range of diversity present in the loci examined, the results were consistent across genes. P. h. rubellus from the SW Indian Ocean comprised the most divergent lineage that was reciprocally monophyletic with respect to all other P. homarus (approx. 9% divergence in COI), and has likely evolved reproductive barriers. The putative P. h. “Brown” subspecies from the Marquesas Is in the central Pacific also comprised a somewhat divergent monophyletic lineage (approx. 3% in COI), but may simply be an allopatric population. The widespread P. h. homarus was not diverged at all from the described P. h. megasculpta from the NW Indian Ocean. The degree of evolutionary divergence of populations at the extremes distribution of the species is somewhat surprising, given the long pelagic larval stage, but suggests that allopatric speciation has been an important driver in the evolution of the genus. PMID:24892781

  9. Polymorphism and partial characterization of digestive enzymes in the spiny lobster Panulirus argus.

    PubMed

    Perera, Erick; Moyano, F J; Díaz, M; Perdomo-Morales, R; Montero-Alejo, V; Alonso, E; Carrillo, O; Galich, G S

    2008-07-01

    We characterized major digestive enzymes in Panulirus argus using a combination of biochemical assays and substrate-(SDS or native)-PAGE. Protease and amylase activities were found in the gastric juice while esterase and lipase activities were higher in the digestive gland. Trypsin-like activity was higher than chymotrypsin-like activity in the gastric juice and digestive gland. Stability and optimal conditions for digestive enzyme activities were examined under different pHs, temperature and ionic strength. The use of protease inhibitors showed the prevalence of serine proteases and metalloproteases. Results for serine proteases were corroborated by zymograms where several isotrypsins-like (17-21 kDa) and isochymotrypsin-like enzymes (23-38 kDa) were identified. Amylases (38-47 kDa) were detected in zymograms and a complex array of non-specific esterases isoenzymes was found in the digestive gland. Isoenzyme polymorphism was found for trypsin, amylase, and esterase. This study is the first to evidence the biochemical bases of the plasticity in feeding habits of P. argus. Distribution and properties of enzymes provided some indication on how the digestion takes place and constitute baseline data for further studies on the digestion physiology of spiny lobsters.

  10. Exceptional minute sex-specific region in the X0 mammal, Ryukyu spiny rat.

    PubMed

    Kobayashi, Tsuyoshi; Yamada, Fumio; Hashimoto, Takuma; Abe, Shintaro; Matsuda, Yoichi; Kuroiwa, Asato

    2007-01-01

    The Ryukyu spiny rats (genus Tokudaia) inhabit only three islands in the Nansei Shoto archipelago in Japan, and have the variations of karyotype among the islands. The chromosome number of T. osimensis in Amami-Oshima Island is 2n = 25, and T. tokunoshimensis in Tokunoshima Island is 2n = 45, and the two species have X0 sex chromosome constitution with no cytogenetically visible Y chromosome in both sexes. We constructed the standard ideograms for these species at the 100 and 200 band levels. Comparing the banding patterns between these species, it was suggested that at least 10 times the number of Robertsonian fusions occurred in T. osimensis chromosomes. However, no karyotypic differences were observed between sexes in each species. To detect the sex-specific chromosomal region of these X0 species we applied the comparative genomic hybridization (CGH) method. Although the male- and female-derived gains and losses were detected in several chromosome regions, all of them were located in the heterochromatic and/or telomeric regions. This result suggested that the differences detected by CGH might be caused by the polymorphism on the copy numbers of repeated sequences in the heterochromatic and telomeric regions. Our result indicated that the sex-specific region, where the key to sex determination lies, is very minute in X0 species of Tokudaia.

  11. Characterization of the immunoglobulin repertoire of the spiny dogfish (Squalus acanthias).

    PubMed

    Smith, Lauren E; Crouch, Kathryn; Cao, Wei; Müller, Mischa R; Wu, Leeying; Steven, John; Lee, Michael; Liang, Musen; Flajnik, Martin F; Shih, Heather H; Barelle, Caroline J; Paulsen, Janet; Gill, Davinder S; Dooley, Helen

    2012-04-01

    The cartilaginous fish (chimeras, sharks, skates and rays) are the oldest group relative to mammals in which an adaptive immune system founded upon immunoglobulins has been found. In this manuscript we characterize the immunoglobulins of the spiny dogfish (Squalus acanthias) at both the molecular and expressed protein levels. Despite the presence of hundreds of IgM clusters in this species the serum levels of this isotype are comparatively low. However, analysis of cDNA sequences and serum protein suggests microheterogeneity in the IgM heavy chains and supports the proposal that different clusters are preferentially used in the two forms (monomer or pentamer) of this isotype. We also found that the IgNAR isotype in this species exists in a previously unknown multimeric format in serum. Finally, we identified a new form of the IgW isotype (the shark IgD orthologue), in which the leader is spliced directly to the first constant domain, resulting in a molecule lacking an antigen-binding domain.

  12. Four new non-spiny Solanum (Solanaceae) species from South America.

    PubMed

    Särkinen, Tiina; Gonzáles, Paúl; Knapp, Sandra

    2015-01-01

    Four new species of "non-spiny" Solanum from South America are described. Solanumlongifilamentum Särkinen & P.Gonzáles, sp. nov. (Morelloid clade) is widespread from Ecuador to Bolivia and is most similar to Solanummacrotonum Dunal from Central and northern South America. Solanumantisuyo Särkinen & S.Knapp, sp. nov. (Morelloid clade) is found on the eastern Andean slopes in Ecuador, Peru and Bolivia and is most similar to the widespread lower elevation species Solanumpolytrichostylum Bitter. Solanumarenicola Särkinen & P.Gonzáles, sp. nov. (Morelloid clade) is found in low elevation habitats on the eastern Andean slopes and in Amazonia of Peru and Bolivia and is most similar to the higher elevation species Solanumaloysiifolium Dunal of Bolivia and Argentina. Solanummariae Särkinen & S.Knapp, sp. nov. (Potato clade) is endemic to Cajamarca Department in Peru, and is most similar to the widespread Solanumcaripense Dunal. Complete descriptions, distributions and preliminary conservation assessments of all new species are given.

  13. Spontaneous and repetitive cardiac slowdown in the freely moving spiny lobster, Panulirus japonicus.

    PubMed

    Yazawa, T; Katsuyama, T

    2001-12-01

    The fluctuation of heartbeat interval was investigated to assess cardio-regulatory nervous function in freely moving spiny lobsters. This was performed by time series analysis of the heartbeat interval recorded from restrained animals, freely moving animals, and isolated hearts. The heart rate of freely moving animals exhibited on/off switching: i.e., an elevated and maintained rate was repetitively interrupted by periods of decreased rate. Each period was initiated by a sudden decrease in rate and was terminated by an exponential return to normal activity. In order to explain this characteristic change in heart rate, we have constructed a neurotransmitter release-reuptake model for such bi-stable activity of cardio-regulatory nerves. The model was successful in reproducing the characteristic observed fluctuation. In freely moving animals, the brain seems to regulate the heart through the inhibitory nerve in an "on/off" manner. In the hearts of restrained animals and isolated hearts, the heart rate exhibited white-noise like fluctuation. This implies that stress impairs the normal bi-stable regulatory mode.

  14. The trypsin inhibitor panulirin regulates the prophenoloxidase-activating system in the spiny lobster Panulirus argus.

    PubMed

    Perdomo-Morales, Rolando; Montero-Alejo, Vivian; Corzo, Gerardo; Besada, Vladimir; Vega-Hurtado, Yamile; González-González, Yamile; Perera, Erick; Porto-Verdecia, Marlene

    2013-11-01

    The melanization reaction promoted by the prophenoloxidase-activating system is an essential defense response in invertebrates subjected to regulatory mechanisms that are still not fully understood. We report here the finding and characterization of a novel trypsin inhibitor, named panulirin, isolated from the hemocytes of the spiny lobster Panulirus argus with regulatory functions on the melanization cascade. Panulirin is a cationic peptide (pI 9.5) composed of 48 amino acid residues (5.3 kDa), with six cysteine residues forming disulfide bridges. Its primary sequence was determined by combining Edman degradation/N-terminal sequencing and electrospray ionization-MS/MS spectrometry. The low amino acid sequence similarity with known proteins indicates that it represents a new family of peptidase inhibitors. Panulirin is a competitive and reversible tight-binding inhibitor of trypsin (Ki = 8.6 nm) with a notable specificity because it does not inhibit serine peptidases such as subtilisin, elastase, chymotrypsin, thrombin, and plasmin. The removal of panulirin from the lobster hemocyte lysate leads to an increase in phenoloxidase response to LPS. Likewise, the addition of increasing concentrations of panulirin to a lobster hemocyte lysate, previously depleted of trypsin-inhibitory activity, decreased the phenoloxidase response to LPS in a concentration-dependent fashion. These results indicate that panulirin is implicated in the regulation of the melanization cascade in P. argus by inhibiting peptidase(s) in the pathway toward the activation of the prophenoloxidase enzyme.

  15. A chymotrypsin from the Digestive Tract of California Spiny Lobster, Panulirus interruptus: Purification and Biochemical Characterization.

    PubMed

    Bibo-Verdugo, Betsaida; Rojo-Arreola, Liliana; Navarrete-del-Toro, Maria A; García-Carreño, Fernando

    2015-08-01

    A chymotrypsin was purified from the gastric juice of California spiny lobster (Panulirus interrutpus), using preparative electrophoresis and affinity chromatography on agarose-p-aminobenzamidine. The molecular mass was estimated by polyacrylamide gel electrophoresis (SDS-PAGE) under denaturing conditions to be 28 kDa. Chymotrypsin activity was totally inhibited by phenylmethylsulfonyl fluoride (PMSF) and chymostatin. Lobster chymotrypsin had optimal pH 7.0-8.0 and temperature of 55 °C. The enzyme is highly stable under a wide range of pH (retaining up to 80 % of activity after 1 h of incubation at pH 3.0, 5.0, and 12.0), showing higher stability at pH 8.0, and was inactivated after 20 min at 55 °C. Lobster chymotrypsin was able to hydrolyze protein substrates at as low as pH 3.0. These results are consistent with the findings of enzyme stability. Activity was assessed after incubation of enzyme with different organic solvents (in the range of 10-50 %); when tested in the presence of acetone, ethanol, propanol, and butanol, lobster chymotrypsin residual activity was >80 %; whereas in the presence of dimethyl sulfoxide (DMSO) and toluene, lobster chymotrypsin residual activity was <80 %. Deduced amino acid sequence, corroborated by mass spectrometry, was determined.

  16. Plasticity in fecundity highlights the females' importance in the spiny-cheek crayfish invasion mechanism.

    PubMed

    Pârvulescu, Lucian; Pîrvu, Mălina; Moroşan, Loredana-Giorgiana; Zaharia, Claudia

    2015-12-01

    Invasion is one of the most consequential phenomena affecting the distribution of native species. Few in number of species, European crayfish are losing the competition with introduced North American crayfish. The spiny-cheek crayfish, Orconectes limosus, is an outstanding example, successfully competing against the native narrow-clawed crayfish, Astacus leptodactylus. For four years, we collected data regarding crayfish occurrences, their relative abundance, and the structure of populations in the ongoing colonisation process of O. limosus in the lower Danube. The mature females of both invasive and indigenous crayfish species were analysed with respect to biometry and production of oocytes in relation to the dynamics of invasion. The interspecific comparisons showed no significant differences regarding body size, with an average of approximately 102 mm total length and 31 g wet weight for both species. However, the fecundity of the indigenous species was found to be constant throughout the investigated area, whereas the number of eggs produced by the invasive females was significantly increased at the active front of the invasion. The maximum number of ovarian eggs found was 887 and 1156 in the indigenous species and the invasive species, respectively. We propose the scenario that the invasive species, which carries the deadly crayfish plague, creates an ecological advantage by reducing the populations of indigenous crayfish. Subsequently, the invasive females opportunistically use the available resources to enhance their fecundity, resulting in the acute growth of populations. However, the long-term competitiveness and colonisation success of O. limosus still remain in question.

  17. Assessment of predation risk through conspecific alarm odors by spiny lobsters

    PubMed Central

    2009-01-01

    Strong “alarm odors” emanating from lethally injured conspecifics may indicate an imminent risk of predation to spiny lobsters. In laboratory trials,1 strong conspecific alarm odors elicited avoidance in Panulirus argus, a highly gregarious species that displays collective defense behavior, but not in Panulirus guttatus, a species that tends to aggregate when reproductive activity is high (spring) but not when it is low (late summer) and does not display collective defensive behavior. To reduce predation risk, however, lobsters may autotomize limbs, thus sustaining nonlethal injuries. I tested the response of these lobsters to scents emanating from intact, lethally-injured and non-lethally injured conspecifics. In P. argus, these scents elicited, respectively, attraction, avoidance and a random response, suggesting that, in P. argus, avoidance of conspecific alarm odors depends on their strength. In contrast, P. guttatus lobsters responded at random to scents of lethally injured conspecifics and showed a similar response to scents of intact and non-lethally injured conspecifics in the spring (attraction) and in the summer (random), reflecting the more cryptic defensive behavior of this species. Therefore, both species use conspecific alarm odors for risk-assessment, but each responds to these cues in the most effective way to reduce its risk of predation. PMID:19721871

  18. Antennule morphology and flicking kinematics facilitate odor sampling by the spiny lobster, Panulirus argus.

    PubMed

    Reidenbach, Matthew A; George, Nicole; Koehl, M A R

    2008-09-01

    Many arthropod olfactory appendages bear arrays of hair-like chemosensory sensillae. Odor molecules in the fluid around the animal must reach the surfaces of those hairs to be sensed. We used the lateral flagellum of the olfactory antennule of the spiny lobster, Panulirus argus, as a system to study how the morphology, orientation, and motion of sensilla-bearing appendages affects the small-scale water flow within the hair array. We tested whether antennule flicking enables lobsters to take discrete odor samples by measuring flow fields through an aesthetasc array on a dynamically scaled physical model of a P. argus antennule. Particle image velocimetry revealed that the magnitude and duration of velocity through the aesthetasc array during the rapid flick downstroke is just enough to allow complete replacement of the fluid entrained within the hair array. The complex zig-zag arrangement of aesthetascs hairs, combined with their offset orientation along the antennule, generates flow velocities that are uniform along the length of the hairs. This increases fluid exchange during the flick and reduces the boundary layer thickness surrounding the hairs. The return stroke occurs at about a quarter the speed of the flick, but the velocity of the fluid between the aesthetascs is approximately 25 times slower. The retained fluid during the return stroke remains virtually unstirred and sufficient time occurs for odor molecules to diffuse to aesthetasc surfaces.

  19. The Trypsin Inhibitor Panulirin Regulates the Prophenoloxidase-activating System in the Spiny Lobster Panulirus argus

    PubMed Central

    Perdomo-Morales, Rolando; Montero-Alejo, Vivian; Corzo, Gerardo; Besada, Vladimir; Vega-Hurtado, Yamile; González-González, Yamile; Perera, Erick; Porto-Verdecia, Marlene

    2013-01-01

    The melanization reaction promoted by the prophenoloxidase-activating system is an essential defense response in invertebrates subjected to regulatory mechanisms that are still not fully understood. We report here the finding and characterization of a novel trypsin inhibitor, named panulirin, isolated from the hemocytes of the spiny lobster Panulirus argus with regulatory functions on the melanization cascade. Panulirin is a cationic peptide (pI 9.5) composed of 48 amino acid residues (5.3 kDa), with six cysteine residues forming disulfide bridges. Its primary sequence was determined by combining Edman degradation/N-terminal sequencing and electrospray ionization-MS/MS spectrometry. The low amino acid sequence similarity with known proteins indicates that it represents a new family of peptidase inhibitors. Panulirin is a competitive and reversible tight-binding inhibitor of trypsin (Ki = 8.6 nm) with a notable specificity because it does not inhibit serine peptidases such as subtilisin, elastase, chymotrypsin, thrombin, and plasmin. The removal of panulirin from the lobster hemocyte lysate leads to an increase in phenoloxidase response to LPS. Likewise, the addition of increasing concentrations of panulirin to a lobster hemocyte lysate, previously depleted of trypsin-inhibitory activity, decreased the phenoloxidase response to LPS in a concentration-dependent fashion. These results indicate that panulirin is implicated in the regulation of the melanization cascade in P. argus by inhibiting peptidase(s) in the pathway toward the activation of the prophenoloxidase enzyme. PMID:24047891

  20. Phenoloxidase activity in the hemolymph of the spiny lobster Panulirus argus.

    PubMed

    Perdomo-Morales, R; Montero-Alejo, V; Perera, E; Pardo-Ruiz, Z; Alonso-Jiménez, E

    2007-12-01

    The prophenoloxidase activating system plays a major role in the defense mechanism of arthropods. In the present study, the phenoloxidase activity and its location in the hemolymph of the spiny lobster Panulirus argus is presented. Phenoloxidase activity was observed in the hemocyte lysate supernatant (HLS) and plasma after their incubation with trypsin. Higher amounts of trypsin were required to activate the HLS prophenoloxidase, due to the presence of a trypsin inhibitor in this fraction. Activation of prophenoloxidase was found when HLS was incubated with calcium, with an optimal pH between 7.5 and 8. This spontaneous activity is due to the prophenoloxidase activating enzyme, a serine proteinase that activates the prophenoloxidase once calcium ions were available. SDS was able to induce phenoloxidase activity in plasma and hemocyte fractions. Prophenoloxidase from HLS occurs as an aggregate of 300kDa. Electrophoretic studies combining SDS-PAGE and native PAGE indicate that different proteins produced the phenoloxidase activity found in HLS and plasma. Thus, as in most crustaceans, Panulirus argus contains a prophenoloxidase activating system in its hemocyte, comprising at least the prophenoloxidase activating enzyme and the prophenoloxidase. Finally, it is suggested that phenoloxidase activity found in plasma is produced by hemocyanin.

  1. Phylogeny and tempo of diversification in the superradiation of spiny-rayed fishes.

    PubMed

    Near, Thomas J; Dornburg, Alex; Eytan, Ron I; Keck, Benjamin P; Smith, W Leo; Kuhn, Kristen L; Moore, Jon A; Price, Samantha A; Burbrink, Frank T; Friedman, Matt; Wainwright, Peter C

    2013-07-30

    Spiny-rayed fishes, or acanthomorphs, comprise nearly one-third of all living vertebrates. Despite their dominant role in aquatic ecosystems, the evolutionary history and tempo of acanthomorph diversification is poorly understood. We investigate the pattern of lineage diversification in acanthomorphs by using a well-resolved time-calibrated phylogeny inferred from a nuclear gene supermatrix that includes 520 acanthomorph species and 37 fossil age constraints. This phylogeny provides resolution for what has been classically referred to as the "bush at the top" of the teleost tree, and indicates acanthomorphs originated in the Early Cretaceous. Paleontological evidence suggests acanthomorphs exhibit a pulse of morphological diversification following the end Cretaceous mass extinction; however, the role of this event on the accumulation of living acanthomorph diversity remains unclear. Lineage diversification rates through time exhibit no shifts associated with the end Cretaceous mass extinction, but there is a global decrease in lineage diversification rates 50 Ma that occurs during a period when morphological disparity among fossil acanthomorphs increases sharply. Analysis of clade-specific shifts in diversification rates reveal that the hyperdiversity of living acanthomorphs is highlighted by several rapidly radiating lineages including tunas, gobies, blennies, snailfishes, and Afro-American cichlids. These lineages with high diversification rates are not associated with a single habitat type, such as coral reefs, indicating there is no single explanation for the success of acanthomorphs, as exceptional bouts of diversification have occurred across a wide array of marine and freshwater habitats.

  2. Australian spiny mountain crayfish and their temnocephalan ectosymbionts: an ancient association on the edge of coextinction?

    PubMed

    Hoyal Cuthill, Jennifer F; Sewell, Kim B; Cannon, Lester R G; Charleston, Michael A; Lawler, Susan; Littlewood, D Timothy J; Olson, Peter D; Blair, David

    2016-05-25

    Australian spiny mountain crayfish (Euastacus, Parastacidae) and their ecotosymbiotic temnocephalan flatworms (Temnocephalida, Platyhelminthes) may have co-occurred and interacted through deep time, during a period of major environmental change. Therefore, reconstructing the history of their association is of evolutionary, ecological, and conservation significance. Here, time-calibrated Bayesian phylogenies of Euastacus species and their temnocephalans (Temnohaswellia and Temnosewellia) indicate near-synchronous diversifications from the Cretaceous. Statistically significant cophylogeny correlations between associated clades suggest linked evolutionary histories. However, there is a stronger signal of codivergence and greater host specificity in Temnosewellia, which co-occurs with Euastacus across its range. Phylogeography and analyses of evolutionary distinctiveness (ED) suggest that regional differences in the impact of climate warming and drying had major effects both on crayfish and associated temnocephalans. In particular, Euastacus and Temnosewellia show strong latitudinal gradients in ED and, conversely, in geographical range size, with the most distinctive, northern lineages facing the greatest risk of extinction. Therefore, environmental change has, in some cases, strengthened ecological and evolutionary associations, leaving host-specific temnocephalans vulnerable to coextinction with endangered hosts. Consequently, the extinction of all Euastacus species currently endangered (75%) predicts coextinction of approximately 60% of the studied temnocephalans, with greatest loss of the most evolutionarily distinctive lineages.

  3. Ontogenetic Variation in the Thermal Biology of Yarrow's Spiny Lizard, Sceloporus jarrovii

    PubMed Central

    Gilbert, Anthony L.; Lattanzio, Matthew S.

    2016-01-01

    Climate change is rapidly altering the way current species interact with their environment to satisfy life-history demands. In areas anticipated to experience extreme warming, rising temperatures are expected to diminish population growth, due either to environmental degradation, or the inability to tolerate novel temperature regimes. Determining how at risk ectotherms, and lizards in particular, are to changes in climate traditionally emphasizes the thermal ecology and thermal sensitivity of physiology of adult members of a population. In this study, we reveal ontogenetic differences in thermal physiological and ecological traits that have been used to anticipate how ectotherms will respond to climate change. We show that the thermal biological traits of juvenile Yarrow’s Spiny Lizards (Sceloporus jarrovii) differ from the published estimates of the same traits for adult lizards. Juvenile S. jarrovii differ in their optimal performance temperature, field field-active body temperature, and critical thermal temperatures compared to adult S. jarrovii. Within juvenile S. jarrovii, males and females exhibit differences in field-active body temperature and desiccation tolerance. Given the observed age- and sex-related variation in thermal physiology, we argue that not including physiological differences in thermal biology throughout ontogeny may lead to misinterpretation of patterns of ecological or evolutionary change due to climate warming. Further characterizing the potential for ontogenetic changes in thermal biology would be useful for a more precise and accurate estimation of the role of thermal physiology in mediating population persistence in warmer environments. PMID:26840620

  4. Reassessment of spiny dogfish Squalus acanthias age and growth using vertebrae and dorsal-fin spines.

    PubMed

    Bubley, W J; Kneebone, J; Sulikowski, J A; Tsang, P C W

    2012-04-01

    Male and female spiny dogfish Squalus acanthias were collected in the western North Atlantic Ocean in the Gulf of Maine between July 2006 and June 2009. Squalus acanthias ranged from 25 to 102 cm stretch total length and were caught during all months of the year except January. Age estimates derived from banding patterns visible in both the vertebrae and second dorsal-fin spines were compared. Vertebral growth increments were visualized using a modified histological staining technique, which was verified as appropriate for obtaining age estimates. Marginal increment analysis of vertebrae verified the increment periodicity, suggesting annual band deposition. Based on increased precision and accuracy of age estimates, as well as more biologically realistic parameters generated in growth models, the current study found that vertebrae provided a more reliable and accurate means of estimating age in S. acanthias than the second dorsal-fin spine. Age estimates obtained from vertebrae ranged from <1 year-old to 17 years for male and 24 years for female S. acanthias. The two-parameter von Bertalanffy growth model fit to vertebrae-derived age estimates produced parameters of L∞ = 94·23 cm and k = 0·11 for males and L∞ = 100·76 cm and k = 0·12 for females. While these growth parameters differed from those previously reported for S. acanthias in the western North Atlantic Ocean, the causes of such differences were beyond the scope of the current study and remain to be determined.

  5. Ontogenetic Variation in the Thermal Biology of Yarrow's Spiny Lizard, Sceloporus jarrovii.

    PubMed

    Gilbert, Anthony L; Lattanzio, Matthew S

    2016-01-01

    Climate change is rapidly altering the way current species interact with their environment to satisfy life-history demands. In areas anticipated to experience extreme warming, rising temperatures are expected to diminish population growth, due either to environmental degradation, or the inability to tolerate novel temperature regimes. Determining how at risk ectotherms, and lizards in particular, are to changes in climate traditionally emphasizes the thermal ecology and thermal sensitivity of physiology of adult members of a population. In this study, we reveal ontogenetic differences in thermal physiological and ecological traits that have been used to anticipate how ectotherms will respond to climate change. We show that the thermal biological traits of juvenile Yarrow's Spiny Lizards (Sceloporus jarrovii) differ from the published estimates of the same traits for adult lizards. Juvenile S. jarrovii differ in their optimal performance temperature, field field-active body temperature, and critical thermal temperatures compared to adult S. jarrovii. Within juvenile S. jarrovii, males and females exhibit differences in field-active body temperature and desiccation tolerance. Given the observed age- and sex-related variation in thermal physiology, we argue that not including physiological differences in thermal biology throughout ontogeny may lead to misinterpretation of patterns of ecological or evolutionary change due to climate warming. Further characterizing the potential for ontogenetic changes in thermal biology would be useful for a more precise and accurate estimation of the role of thermal physiology in mediating population persistence in warmer environments.

  6. The oxygen-binding modulation of hemocyanin from the Southern spiny lobster Palinurus gilchristi.

    PubMed

    Olianas, Alessandra; Manconi, Barbara; Masia, Daniela; Sanna, Maria T; Castagnola, Massimo; Salvadori, Susanna; Messana, Irene; Giardina, Bruno; Pellegrini, Mariagiuseppina

    2009-02-01

    Arthropod hemocyanins transport and store oxygen and are composed of six subunits, or multiples thereof depending on the species. Palinurus gilchristi hemocyanin is found only as 1 x 6-mers, as normally occurs in spiny lobsters. An alkaline pH and removal of calcium ions induce a wholly reversible dissociation into monomers. The oxygen-binding properties of 1 x 6-meric hemocyanin from P. gilchristi were investigated with respect to pH and modulating effect exerted by calcium, lactate and urate. The oxygen affinity was highly affected by pH in the presence of calcium ions, while in its absence the Bohr coefficient became 60% lower. The protein is insensitive to lactate, but affected by urate which markedly increased hemocyanin-oxygen affinity, acting as the physiological major positive effector. Calcium ions decrease oxygen affinity at low concentration range (0-1 mM), while as concentration becomes higher than 100 mM, the oxygen affinity increases, indicating the presence of two independent types of calcium-binding sites with high and low affinity, respectively. The previous hypothesis, that the presence of high-affinity binding sites in addition to low affinity ones could be a characteristic feature of Palinuran hemocyanins, has been tested by analyzing, with respect to calcium-hemocyanin interaction, three other species belonging to Palinura.

  7. Proximate control of diel vertical migration in Phyllosoma larvae of the Caribbean spiny lobster Panulirus argus.

    PubMed

    Ziegler, Tracy A; Cohen, Jonathan H; Forward, Richard B

    2010-12-01

    Phyllosoma larvae of the spiny lobster Panulirus argus undergo diel vertical migration (DVM), in which they are at depth during the day and nearer the surface at night. This study determined the visual spectral sensitivity of Stage I larvae and investigated whether light plays a proximate role in DVM as an exogenous cue and as an entrainment cue for an endogenous rhythm in vertical migration. Under constant conditions, larvae have a circadian rhythm (24.5-h period) in vertical swimming that resulted in a twilight DVM pattern. The behavioral response spectrum and electroretinogram recording indicated two photoreceptor spectral classes with maxima at 360 and 486 nm. When stimulated in an apparatus that simulated the underwater angular light distribution, dark-adapted larvae showed only positive phototaxis, with a threshold intensity of 1.8 × 10(13) photons m(-2) s(-1) (3.0 × 10(-5) μmoles photons m(-2) s(-1)). They have an avoidance response to predator shadows in which they descend upon sudden decreases in light intensity of more than 69%. When stimulated with relative rates of decrease in light intensity as occur at sunset they ascended, whereas they descended upon relative rates of light intensity increase as occur at sunrise. Thus, the DVM pattern is controlled by both an endogenous circadian rhythm in swimming and behavioral responses to light at sunrise and sunset.

  8. Probiont niche specialization contributes to additive protection against Vibrio owensii in spiny lobster larvae.

    PubMed

    Goulden, Evan F; Hall, Michael R; Pereg, Lily L; Baillie, Brett K; Høj, Lone

    2013-02-01

    The development of efficient probiotic application protocols for use in marine larviculture relies on comprehensive understanding of pathogen-probiont-host interactions. The probiont combination of Pseudoalteromonas sp. PP107 and Vibrio sp. PP05 provides additive protection against vectored Vibrio owensii DY05 infection in larvae (phyllosomas) of ornate spiny lobster, Panulirus ornatus. Here, fluorescently tagged strains were used to demonstrate niche specialization of these probionts in both the live feed vector organism Artemia and in phyllosomas. The pathogen was vulnerable to direct interaction with PP05 in the bacterioplankton as well as in the Artemia gut and the phyllosoma foregut and midgut gland. In contrast, PP107 was localized on external surfaces of Artemia and phyllosomas, and direct interaction with the pathogen was limited to the bacterioplankton. While PP107 was the overall dominant ectobiont on the phyllosoma cephalothorax and inner leg segments, PP05 was the primary colonizer of outer leg segments, nutrient-rich locales that may promote ingestion during feeding. This study shows that niche specialization can contribute to the additive probiotic effect of a probiotic mixture and highlights that probiotic enrichment of Artemia cultures can intercept the infection cycle of V. owensii DY05 in early-stage P. ornatus phyllosomas.

  9. Synaptic Conductance Estimates of the Connection Between Local Inhibitor Interneurons and Pyramidal Neurons in Layer 2/3 of a Cortical Column

    PubMed Central

    Hoffmann, Jochen H.O.; Meyer, H. S.; Schmitt, Arno C.; Straehle, Jakob; Weitbrecht, Trinh; Sakmann, Bert; Helmstaedter, Moritz

    2015-01-01

    Stimulation of a principal whisker yields sparse action potential (AP) spiking in layer 2/3 (L2/3) pyramidal neurons in a cortical column of rat barrel cortex. The low AP rates in pyramidal neurons could be explained by activation of interneurons in L2/3 providing inhibition onto L2/3 pyramidal neurons. L2/3 interneurons classified as local inhibitors based on their axonal projection in the same column were reported to receive strong excitatory input from spiny neurons in L4, which are also the main source of the excitatory input to L2/3 pyramidal neurons. Here, we investigated the remaining synaptic connection in this intracolumnar microcircuit. We found strong and reliable inhibitory synaptic transmission between intracolumnar L2/3 local-inhibitor-to-L2/3 pyramidal neuron pairs [inhibitory postsynaptic potential (IPSP) amplitude −0.88 ± 0.67 mV]. On average, 6.2 ± 2 synaptic contacts were made by L2/3 local inhibitors onto L2/3 pyramidal neurons at 107 ± 64 µm path distance from the pyramidal neuron soma, thus overlapping with the distribution of synaptic contacts from L4 spiny neurons onto L2/3 pyramidal neurons (67 ± 34 µm). Finally, using compartmental simulations, we determined the synaptic conductance per synaptic contact to be 0.77 ± 0.4 nS. We conclude that the synaptic circuit from L4 to L2/3 can provide efficient shunting inhibition that is temporally and spatially aligned with the excitatory input from L4 to L2/3. PMID:25761638

  10. Cholinergic control of firing pattern and neurotransmission in rat neostriatal projection neurons: role of CaV2.1 and CaV2.2 Ca2+ channels.

    PubMed

    Perez-Rosello, Tamara; Figueroa, Alejandra; Salgado, Humberto; Vilchis, Carmen; Tecuapetla, Fatuel; Guzman, Jaime N; Galarraga, Elvira; Bargas, Jose

    2005-05-01

    Besides a reduction of L-type Ca2+-currents (Ca(V)1), muscarine and the peptidic M1-selective agonist, MT-1, reduced currents through Ca(V)2.1 (P/Q) and Ca(V)2.2 (N) Ca2+ channel types. This modulation was strongly blocked by the peptide MT-7, a specific muscarinic M1-type receptor antagonist but not significantly reduced by the peptide MT-3, a specific muscarinic M4-type receptor antagonist. Accordingly, MT-7, but not MT-3, blocked a muscarinic reduction of the afterhyperpolarizing potential (AHP) and decreased the GABAergic inhibitory postsynaptic currents (IPSCs) produced by axon collaterals that interconnect spiny neurons. Both these functions are known to be dependent on P/Q and N types Ca2+ channels. The action on the AHP had an important effect in increasing firing frequency. The action on the IPSCs was shown to be caused presynaptically as it coursed with an increase in the paired-pulse ratio. These results show: first, that muscarinic M1-type receptor activation is the main cholinergic mechanism that modulates Ca2+ entry through voltage-dependent Ca2+ channels in spiny neurons. Second, this muscarinic modulation produces a postsynaptic facilitation of discharge together with a presynaptic inhibition of the GABAergic control mediated by axon collaterals. Together, both effects would tend to recruit more spiny neurons for the same task.

  11. Levels of mercury in muscle and liver of star-spotted dogfish (Mustelus manazo) from the northern region of Japan: a comparison with spiny dogfish (Squalus acanthias).

    PubMed

    Endo, Tetsuya; Hisamichi, Yohsuke; Kimura, Osamu; Ogasawara, Hideki; Ohta, Chiho; Koga, Nobuyuki; Kato, Yoshihisa; Haraguchi, Koichi

    2013-04-01

    We analyzed mercury (Hg) concentrations in muscle and liver samples of star-spotted dogfish (Mustelus manazo) caught off the northern region of Japan and compared them with those of spiny dogfish (Squalus acanthias) caught in the same region. The average body length of male star-spotted dogfish specimens was significantly smaller than that of female specimens, reflecting the slower growth rate of male fish. Hg concentrations in liver and muscle increased with increases in body length and estimated age of both male and female star-spotted dogfish specimens. However, the relationships between Hg concentration in liver or muscle and body length or estimated age of male specimens differed markedly from those of female specimens, reflecting differences in growth rate and cessation of growth on reaching maturity. Marked increases in Hg concentration in liver of male and female star-spotted dogfish specimens were observed slightly later than increases in Hg concentration in muscle of those specimens due to growth cessation. These marked increases in Hg in liver may reflect increases in Hg due to the formation of mercury selenide. Similar results were previously reported in spiny dogfish specimens, except spiny dogfish showed only trace levels of Hg in liver (Endo et al., Chemosphere 77:1333-1337, 2009). The greater lipid content in liver and the larger liver size in spiny dogfish may explain the much lower levels of Hg observed in liver of spiny dogfish compared with those in the star-spotted dogfish.

  12. The Limited Utility of Multiunit Data in Differentiating Neuronal Population Activity

    PubMed Central

    Keller, Corey J.; Khodakhah, Kamran

    2016-01-01

    To date, single neuron recordings remain the gold standard for monitoring the activity of neuronal populations. Since obtaining single neuron recordings is not always possible, high frequency or ‘multiunit activity’ (MUA) is often used as a surrogate. Although MUA recordings allow one to monitor the activity of a large number of neurons, they do not allow identification of specific neuronal subtypes, the knowledge of which is often critical for understanding electrophysiological processes. Here, we explored whether prior knowledge of the single unit waveform of specific neuron types is sufficient to permit the use of MUA to monitor and distinguish differential activity of individual neuron types. We used an experimental and modeling approach to determine if components of the MUA can monitor medium spiny neurons (MSNs) and fast-spiking interneurons (FSIs) in the mouse dorsal striatum. We demonstrate that when well-isolated spikes are recorded, the MUA at frequencies greater than 100Hz is correlated with single unit spiking, highly dependent on the waveform of each neuron type, and accurately reflects the timing and spectral signature of each neuron. However, in the absence of well-isolated spikes (the norm in most MUA recordings), the MUA did not typically contain sufficient information to permit accurate prediction of the respective population activity of MSNs and FSIs. Thus, even under ideal conditions for the MUA to reliably predict the moment-to-moment activity of specific local neuronal ensembles, knowledge of the spike waveform of the underlying neuronal populations is necessary, but not sufficient. PMID:27111446

  13. Bifurcation diagram globally underpinning neuronal firing behaviors modified by SK conductance

    NASA Astrophysics Data System (ADS)

    Chen, Meng-Jiao; Ling, Heng-Li; Liu, Yi-Hui; Qu, Shi-Xian; Ren, Wei

    2014-02-01

    Neurons in the brain utilize various firing trains to encode the input signals they have received. Firing behavior of one single neuron is thoroughly explained by using a bifurcation diagram from polarized resting to firing, and then to depolarized resting. This explanation provides an important theoretical principle for understanding neuronal biophysical behaviors. This paper reports the novel experimental and modeling results of the modification of such a bifurcation diagram by adjusting small conductance potassium (SK) channel. In experiments, changes in excitability and depolarization block in nucleus accumbens shell and medium-spiny projection neurons are explored by increasing the intensity of injected current and blocking the SK channels by apamin. A shift of bifurcation points is observed. Then, a Hodgkin—Huxley type model including the main electrophysiological processes of such neurons is developed to reproduce the experimental results. The reduction of SK channel conductance also shifts the bifurcations, which is in consistence with experiment. A global bifurcation paradigm of this shift is obtained by adjusting two parameters, intensity of injected current and SK channel conductance. This work reveals the dynamics underpinning modulation of neuronal firing behaviors by biologically important ionic conductance. The results indicate that small ionic conductance other than that responsible for spike generation can modify bifurcation points and shift the bifurcation diagram and, thus, change neuronal excitability and adaptation.

  14. Up-regulation of A-type potassium currents protects neurons against cerebral ischemia

    PubMed Central

    Deng, Ping; Pang, Zhi-Ping; Lei, Zhigang; Shikano, Sojin; Xiong, Qiaojie; Harvey, Brandon K; London, Barry; Wang, Yun; Li, Min; Xu, Zao C

    2011-01-01

    Excitotoxicity is the major cause of many neurologic disorders including stroke. Potassium currents modulate neuronal excitability and therefore influence the pathological process. A-type potassium current (IA) is one of the major voltage-dependent potassium currents, yet its roles in excitotoxic cell death are not well understood. We report that, following ischemic insults, the IA increases significantly in large aspiny (LA) neurons but not medium spiny (MS) neurons in the striatum, which correlates with the higher resistance of LA neurons to ischemia. Activation of protein kinase Cα increases IA in LA neurons after ischemia. Cultured neurons from transgenic mice lacking both Kv1.4 and Kv4.2 subunits exhibit an increased vulnerability to ischemic insults. Increase of IA by recombinant expression of Kv1.4 or Kv4.2 is sufficient in improving the survival of MS neurons against ischemic insults both in vitro and in vivo. These results, taken together, provide compelling evidence for a protective role of IA against ischemia. PMID:21673715

  15. Diversity of neural signals mediated by multiple, burst-firing mechanisms in rat olfactory tubercle neurons.

    PubMed

    Chiang, Elizabeth; Strowbridge, Ben W

    2007-11-01

    Olfactory information is processed by a diverse group of interconnected forebrain regions. Most efforts to define the cellular mechanisms involved in processing olfactory information have been focused on understanding the function of the olfactory bulb, the primary second-order olfactory region, and its principal target, the piriform cortex. However, the olfactory bulb also projects to other targets, including the rarely studied olfactory tubercle, a ventral brain region recently implicated in regulating cocaine-related reward behavior. We used whole cell patch-clamp recordings from rat tubercle slices to define the intrinsic properties of neurons in the dense and multiform cell layers. We find three common firing modes of tubercle neurons: regular-spiking, intermittent-discharging, and bursting. Regular-spiking neurons are typically spiny-dense-cell-layer cells with pyramidal-shaped, dendritic arborizations. Intermittently discharging and bursting neurons comprise the majority of the deeper multiform layer and share a common morphology: multipolar, sparsely spiny cells. Rather than generating all-or-none stereotyped discharges, as observed in many brain areas, bursting cells in the tubercle generate depolarizing plateau potentials that trigger graded but time-limited discharges. We find two distinct subclasses of bursting cells that respond similarly to step stimuli but differ in the role transmembrane Ca currents play in their intrinsic behavior. Calcium currents amplify depolarizing inputs and enhance excitability in regenerative bursting cells, whereas the primary action of Ca in nonregenerative bursting tubercle neurons appears to be to decrease excitability by triggering Ca-activated K currents. Nonregenerative bursting cells exhibit a prolonged refractory period after even short discharges suggesting that they may function to detect transient events.

  16. Body ram, not suction, is the primary axis of suction-feeding diversity in spiny-rayed fishes.

    PubMed

    Longo, Sarah J; McGee, Matthew D; Oufiero, Christopher E; Waltzek, Thomas B; Wainwright, Peter C

    2016-01-01

    Suction-feeding fishes exhibit diverse prey-capture strategies that vary in their relative use of suction and predator approach (ram), which is often referred to as the ram-suction continuum. Previous research has found that ram varies more than suction distance among species, such that ram accounts for most differences in prey-capture behaviors. To determine whether these findings hold at broad evolutionary scales, we collected high-speed videos of 40 species of spiny-rayed fishes (Acanthomorpha) feeding on live prey. For each strike, we calculated the contributions of suction, body ram (swimming) and jaw ram (mouth movement relative to the body) to closing the distance between predator and prey. We confirm that the contribution of suction distance is limited even in this phylogenetically and ecologically broad sample of species, with the extreme suction area of prey-capture space conspicuously unoccupied. Instead of a continuum from suction to ram, we find that variation in body ram is the major factor underlying the diversity of prey-capture strategies among suction-feeding fishes. Independent measurement of the contribution of jaw ram revealed that it is an important component of diversity among spiny-rayed fishes, with a number of ecomorphologies relying heavily on jaw ram, including pivot feeding in syngnathiforms, extreme jaw protruders and benthic sit-and-wait ambush predators. A combination of morphological and behavioral innovations has allowed fish to invade the extreme jaw ram area of prey-capture space. We caution that while two-species comparisons may support a ram-suction trade-off, these patterns do not speak to broader patterns across spiny-rayed fishes.

  17. Resistance to starvation of first-stage juveniles of the Caribbean spiny lobster

    PubMed Central

    Lozano-Álvarez, Enrique; Briones-Fourzán, Patricia

    2017-01-01

    The non-feeding postlarva (puerulus) of spiny lobsters actively swims from the open ocean to the coastal habitats where it settles and molts to the first-stage juvenile (JI). Because pueruli use much of their energy reserves swimming and preparing for the post-settlement molt, the survival of JIs presumably depends on resuming feeding as soon as possible. To test this hypothesis, the resistance to starvation of JIs of the Caribbean spiny lobster, Panulirus argus, was evaluated by measuring their point-of-no-return (PNR, minimum time of initial starvation preventing recovery after later feeding) and point-of-reserve-saturation (PRS, minimum time of initial feeding allowing for food-independent development through the rest of the molting cycle) in a warm and a cold season. Each experiment consisted of eight groups: a continuously fed control (FC) group, a continuously starved control (SC) group, and six groups subjected to differential periods of either initial starvation and subsequent feeding (PNR experiments) or initial feeding and subsequent starvation (PSR experiments). No JIs molted under continuous absence of food (SC). In both PNR experiments (temperature in warm season: 29.79 ± 0.07°C, mean ± 95% CI; in cold season: 25.63 ± 0.12°C) mortality increased sharply after 9 d of initial starvation and intermolt periods increased with period of initial starvation, but were longer in the cold season. The PNR50 was longer in the warm season (12.1 ± 1.2 d, mean ± 95% CI) than in the cold season (9.5 ± 2.1 d). In PRS experiments (temperature in warm season: 29.54 ± 0.07 °C; in cold season: 26.20 ± 0.12 °C), JIs that molted did so near the end of the feeding period; all JIs initially fed for up to 6 d succumbed, and no JIs molted after 13 d of starvation despite having fed previously. The PRS50 did not differ between the cold (13.1 ± 0.7 d) and warm seasons (12.1 ± 1.1 d). JIs of P. argus exhibit a remarkable resistance to starvation

  18. Resistance to starvation of first-stage juveniles of the Caribbean spiny lobster.

    PubMed

    Espinosa-Magaña, Alí; Lozano-Álvarez, Enrique; Briones-Fourzán, Patricia

    2017-01-01

    The non-feeding postlarva (puerulus) of spiny lobsters actively swims from the open ocean to the coastal habitats where it settles and molts to the first-stage juvenile (JI). Because pueruli use much of their energy reserves swimming and preparing for the post-settlement molt, the survival of JIs presumably depends on resuming feeding as soon as possible. To test this hypothesis, the resistance to starvation of JIs of the Caribbean spiny lobster, Panulirus argus, was evaluated by measuring their point-of-no-return (PNR, minimum time of initial starvation preventing recovery after later feeding) and point-of-reserve-saturation (PRS, minimum time of initial feeding allowing for food-independent development through the rest of the molting cycle) in a warm and a cold season. Each experiment consisted of eight groups: a continuously fed control (FC) group, a continuously starved control (SC) group, and six groups subjected to differential periods of either initial starvation and subsequent feeding (PNR experiments) or initial feeding and subsequent starvation (PSR experiments). No JIs molted under continuous absence of food (SC). In both PNR experiments (temperature in warm season: 29.79 ± 0.07°C, mean ± 95% CI; in cold season: 25.63 ± 0.12°C) mortality increased sharply after 9 d of initial starvation and intermolt periods increased with period of initial starvation, but were longer in the cold season. The PNR50 was longer in the warm season (12.1 ± 1.2 d, mean ± 95% CI) than in the cold season (9.5 ± 2.1 d). In PRS experiments (temperature in warm season: 29.54 ± 0.07 °C; in cold season: 26.20 ± 0.12 °C), JIs that molted did so near the end of the feeding period; all JIs initially fed for up to 6 d succumbed, and no JIs molted after 13 d of starvation despite having fed previously. The PRS50 did not differ between the cold (13.1 ± 0.7 d) and warm seasons (12.1 ± 1.1 d). JIs of P. argus exhibit a remarkable resistance to starvation

  19. Effects of odor familiarity on the development of systematic exploration in the spiny mouse, Acomys cahirinus.

    PubMed

    Birke, L I; Sadler, D

    1987-11-01

    Developmental changes in patterns of exploration by infant spiny mice, Acomys cahirinus are described. These were investigated using an unbaited radial maze and under three odor conditions; that is, animals were tested in the presence of either familiar (own) odors, unfamiliar conspecific odors, or no odors (washed floor). Two hypotheses were tested. The first was based on the results of a pilot study, and was that adult animals would explore the radial maze in a systematic and predictable fashion tending to move from one arm to the next sequentially. It was hypothesized that infants would adopt this sequential strategy only gradually, as they matured. The second hypothesis was that such patterns of exploration would depend upon the olfactory environment; the presence of familiar odors might facilitate systematic patterns of exploration in very young Acomys. The results showed that both adults and juveniles were less likely to move sequentially when tested with no conspecific odor present; sequential patterns of movement were most likely in the presence of unfamiliar odor, however. The only significant change with age in infants was found for animals tested with unfamiliar odors; these animals showed a dramatic increase in sequential behavior between 3 and 7 days of age. Two additional experiments are reported, which investigated the preferences of infant Acomys for unfamiliar conspecific odors, and it was found that very young (about 3 days) animals exhibit a preference for odors derived from unfamiliar conspecific litters, even when tested in the physical presence of their own parents. The results are discussed with reference to the use of olfactory information as directional cues for animals exploring the radial maze.

  20. Sympatric speciation of spiny mice, Acomys, unfolded transcriptomically at Evolution Canyon, Israel.

    PubMed

    Li, Kexin; Wang, Huihua; Cai, Zhenyuan; Wang, Liuyang; Xu, Qinqin; Lövy, Matěj; Wang, Zhenlong; Nevo, Eviatar

    2016-07-19

    Spiny mice, Acomys cahirinus, colonized Israel 30,000 y ago from dry tropical Africa and inhabited rocky habitats across Israel. Earlier, we had shown by mtDNA that A. cahirinus incipiently sympatrically speciates at Evolution Canyon I (EC I) in Mount Carmel, Israel because of microclimatic interslope divergence. The EC I microsite consists of a dry and hot savannoid "African" slope (AS) and an abutting humid and cool-forested "European" slope (ES). Here, we substantiate incipient SS in A. cahirinus at EC I based on the entire transcriptome, showing that multiple slope-specific adaptive complexes across the transcriptome result in two divergent clusters. Tajima's D distribution of the abutting Acomys interslope populations shows that the ES population is under stronger positive selection, whereas the AS population is under balancing selection, harboring higher genetic polymorphisms. Considerable sites of the two populations were differentiated with a coefficient of FST = 0.25-0.75. Remarkably, 24 and 37 putatively adaptively selected genes were detected in the AS and ES populations, respectively. The AS genes involved DNA repair, growth arrest, neural cell differentiation, and heat-shock proteins adapting to the local AS stresses of high solar radiation, drought, and high temperature. In contrast, the ES genes involved high ATP associated with energetics stress. The sharp ecological interslope divergence led to strong slope-specific selection overruling the interslope gene flow. Earlier tests suggested slope-specific mate choice. Habitat interslope-adaptive selection across the transcriptome and mate choice substantiate sympatric speciation (SS), suggesting its prevalence at EC I and commonality in nature.