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Sample records for medium-sized spiny neurons

  1. Distribution and compartmental organization of GABAergic medium-sized spiny neurons in the mouse nucleus accumbens

    PubMed Central

    Gangarossa, Giuseppe; Espallergues, Julie; de Kerchove d'Exaerde, Alban; El Mestikawy, Salah; Gerfen, Charles R.; Hervé, Denis; Girault, Jean-Antoine; Valjent, Emmanuel

    2012-01-01

    The nucleus accumbens (NAc) is a critical brain region involved in many reward-related behaviors. The NAc comprises major compartments the core and the shell, which encompass several subterritories. GABAergic medium-sized spiny neurons (MSNs) constitute the output neurons of the NAc core and shell. While the functional organization of the NAc core outputs resembles the one described for the dorsal striatum, a simple classification of the NAc shell neurons has been difficult to define due to the complexity of the compartmental segregation of cells. We used a variety of BAC transgenic mice expressing enhanced green fluorescence (EGFP) or the Cre-recombinase (Cre) under the control of the promoter of dopamine D1, D2, and D3 receptors and of adenosine A2a receptor to dissect the microanatomy of the NAc. Moreover, using various immunological markers we characterized in detail the distribution of MSNs in the mouse NAc. In addition, cell-type specific extracellular signal-regulated kinase (ERK) phosphorylation in the NAc subterritories was analyzed following acute administration of SKF81297 (a D1R-like agonist), quinpirole (a D2 receptors (D2R)-like agonist), apomorphine (a non-selective DA receptor agonist), raclopride (a D2R-like antagonist), and psychostimulant drugs, including cocaine and d-amphetamine. Each drug generated a unique topography and cell-type specific activation of ERK in the NAc. Our results show the existence of marked differences in the receptor expression pattern and functional activation of MSNs within the shell subterritories. This study emphasizes the anatomical and functional heterogeneity of the NAc, which will have to be considered in its further study. PMID:23423476

  2. Distribution and compartmental organization of GABAergic medium-sized spiny neurons in the mouse nucleus accumbens.

    PubMed

    Gangarossa, Giuseppe; Espallergues, Julie; de Kerchove d'Exaerde, Alban; El Mestikawy, Salah; Gerfen, Charles R; Hervé, Denis; Girault, Jean-Antoine; Valjent, Emmanuel

    2013-01-01

    The nucleus accumbens (NAc) is a critical brain region involved in many reward-related behaviors. The NAc comprises major compartments the core and the shell, which encompass several subterritories. GABAergic medium-sized spiny neurons (MSNs) constitute the output neurons of the NAc core and shell. While the functional organization of the NAc core outputs resembles the one described for the dorsal striatum, a simple classification of the NAc shell neurons has been difficult to define due to the complexity of the compartmental segregation of cells. We used a variety of BAC transgenic mice expressing enhanced green fluorescence (EGFP) or the Cre-recombinase (Cre) under the control of the promoter of dopamine D1, D2, and D3 receptors and of adenosine A2a receptor to dissect the microanatomy of the NAc. Moreover, using various immunological markers we characterized in detail the distribution of MSNs in the mouse NAc. In addition, cell-type specific extracellular signal-regulated kinase (ERK) phosphorylation in the NAc subterritories was analyzed following acute administration of SKF81297 (a D1R-like agonist), quinpirole (a D2 receptors (D2R)-like agonist), apomorphine (a non-selective DA receptor agonist), raclopride (a D2R-like antagonist), and psychostimulant drugs, including cocaine and d-amphetamine. Each drug generated a unique topography and cell-type specific activation of ERK in the NAc. Our results show the existence of marked differences in the receptor expression pattern and functional activation of MSNs within the shell subterritories. This study emphasizes the anatomical and functional heterogeneity of the NAc, which will have to be considered in its further study. PMID:23423476

  3. L-Phosphinothricin modulation of inwardly rectifying K(+) channels increased excitability in striatal medium-sized spiny neurons.

    PubMed

    Domingos, Laetitia; Desrus, Agnès; Même, Sandra; Même, William

    2016-07-01

    Phosphinotricin (L-PPT) is the active compound of a broad-spectrum herbicide. Acute poisoning with L-PPT has various clinical manifestations, including seizures and convulsions. However, the exact mechanism of L-PPT toxicity remains unclear. The present study addressed the role of L-PPT, in the excitability of striatal medium-sized spiny neurons (MSNs). In whole-cell current-clamp experiments, L-PPT increased the input resistance (Ri), decreased the rheobase and increased the firing frequency of action potentials. In voltage-clamp experiments, L-PPT inhibited the inward-rectifying potassium (Kir) currents. Finally, the effects of L-PPT mimicked the inhibition of Kir channels with Ba(2+) on neuronal excitability. Altogether, these results suggest that the herbicide L-PPT is a modulator of Kir channels in MSNs. Thereby, Kir channels are potent regulators of the excitability of MSNs and reduced open probability of these channels would generate a powerful upregulation of neuronal output. This effect may represent a possible mechanism for L-PPT dependent neuronal toxicity. PMID:27136897

  4. A Neurocomputational Method for Fully Automated 3D Dendritic Spine Detection and Segmentation of Medium-sized Spiny Neurons

    PubMed Central

    Zhang, Yong; Chen, Kun; Baron, Matthew; Teylan, Merilee A.; Kim, Yong; Song, Zhihuan; Greengard, Paul

    2010-01-01

    Acquisition and quantitative analysis of high resolution images of dendritic spines are challenging tasks but are necessary for the study of animal models of neurological and psychiatric diseases. Currently available methods for automated dendritic spine detection are for the most part customized for 2D image slices, not volumetric 3D images. In this work, a fully automated method is proposed to detect and segment dendritic spines from 3D confocal microscopy images of medium-sized spiny neurons (MSNs). MSNs constitute a major neuronal population in striatum, and abnormalities in their function are associated with several neurological and psychiatric diseases. Such automated detection is critical for the development of new 3D neuronal assays which can be used for the screening of drugs and the studies of their therapeutic effects. The proposed method utilizes a generalized gradient vector flow (GGVF) with a new smoothing constraint and then detects feature points near the central regions of dendrites and spines. Then, the central regions are refined and separated based on eigen-analysis and multiple shape measurements. Finally, the spines are segmented in 3D space using the fast marching algorithm, taking the detected central regions of spines as initial points. The proposed method is compared with three popular existing methods for centerline extraction and also with manual results for dendritic spine detection in 3D space. The experimental results and comparisons show that the proposed method is able to automatically and accurately detect, segment, and quantitate dendritic spines in 3D images of MSNs. PMID:20100579

  5. PHOSPHATIDYLINOSITIDE 3-KINASE AND PROTEIN KINASE C ZETA MEDIATE RETINOIC ACID INDUCTION OF DARPP-32 IN MEDIUM SIZE SPINY NEURONS IN VITRO

    PubMed Central

    Pedrini, Steve; Bogush, Alexey; Ehrlich, Michelle E

    2016-01-01

    Mature striatal medium size spiny neurons express the dopamine and cyclic AMP-regulated phosphoprotein, 32 kDa (DARPP-32), but little is known about the mechanisms regulating its levels, or the specification of fully differentiated neuronal subtypes. Cell extrinsic molecules that increase DARPP-32 mRNA and/or protein levels include retinoic acid (RA), brain-derived neurotrophic factor (BDNF), and estrogen (E2). We now demonstrate that RA regulates DARPP-32 mRNA and protein in primary striatal neuronal cultures. Furthermore, DARPP-32 induction by RA in vitro requires phosphatidylinositide 3-kinase (PI3K), but is independent of tropomyosin-related kinase b (TrkB), cyclin-dependent kinase 5 (cdk5), and protein kinase B (Akt). Using pharmacologic inhibitors of various isoforms of protein kinase C, we also demonstrate that DARPP-32 induction by RA in vitro is dependent on protein kinase C zeta (PKCζ). Thus, the signal transduction pathways mediated by RA are very different than those mediating DARPP-32 induction by brain derived neurotrophic factor (BDNF). These data support the presence of multiple signal transduction pathways mediating expression of DARPP-32 in vitro, including a novel, important pathway via which PI3K regulates the contribution of PKCζ. PMID:18485106

  6. PKA-dependent phosphorylation of ribosomal protein S6 does not correlate with translation efficiency in striatonigral and striatopallidal medium-sized spiny neurons.

    PubMed

    Biever, Anne; Puighermanal, Emma; Nishi, Akinori; David, Alexandre; Panciatici, Claire; Longueville, Sophie; Xirodimas, Dimitris; Gangarossa, Giuseppe; Meyuhas, Oded; Hervé, Denis; Girault, Jean-Antoine; Valjent, Emmanuel

    2015-03-11

    Ribosomal protein S6 (rpS6), a component of the 40S ribosomal subunit, is phosphorylated on several residues in response to numerous stimuli. Although commonly used as a marker for neuronal activity, its upstream mechanisms of regulation are poorly studied and its role in protein synthesis remains largely debated. Here, we demonstrate that the psychostimulant d-amphetamine (d-amph) markedly increases rpS6 phosphorylation at Ser235/236 sites in both crude and synaptoneurosomal preparations of the mouse striatum. This effect occurs selectively in D1R-expressing medium-sized spiny neurons (MSNs) and requires the cAMP/PKA/DARPP-32/PP-1 cascade, whereas it is independent of mTORC1/p70S6K, PKC, and ERK signaling. By developing a novel assay to label nascent peptidic chains, we show that the rpS6 phosphorylation induced in striatonigral MSNs by d-amph, as well as in striatopallidal MSNs by the antipsychotic haloperidol or in both subtypes by papaverine, is not correlated with the translation of global or 5' terminal oligopyrimidine tract mRNAs. Together, these results provide novel mechanistic insights into the in vivo regulation of the post-translational modification of rpS6 in the striatum and point out the lack of a relationship between PKA-dependent rpS6 phosphorylation and translation efficiency. PMID:25762659

  7. Drug-primed reinstatement of cocaine seeking in mice: increased excitability of medium-sized spiny neurons in the nucleus accumbens

    PubMed Central

    Ma, Yao-Ying; Henley, Sandy M.; Toll, Jeff; Jentsch, James D.; Evans, Christopher J.; Levine, Michael S.; Cepeda, Carlos

    2013-01-01

    To examine the mechanisms of drug relapse, we first established a model for cocaine IVSA (intravenous self-administration) in mice, and subsequently examined electrophysiological alterations of MSNs (medium-sized spiny neurons) in the NAc (nucleus accumbens) before and after acute application of cocaine in slices. Three groups were included: master mice trained by AL (active lever) pressings followed by IV (intravenous) cocaine delivery, yoked mice that received passive IV cocaine administration initiated by paired master mice, and saline controls. MSNs recorded in the NAc shell in master mice exhibited higher membrane input resistances but lower frequencies and smaller amplitudes of sEPSCs (spontaneous excitatory postsynaptic currents) compared with neurons recorded from saline control mice, whereas cells in the NAc core had higher sEPSCs frequencies and larger amplitudes. Furthermore, sEPSCs in MSNs of the shell compartment displayed longer decay times, suggesting that both pre- and postsynaptic mechanisms were involved. After acute re-exposure to a low-dose of cocaine in vitro, an AP (action potential)-dependent, persistent increase in sEPSC frequency was observed in both NAc shell and core MSNs from master, but not yoked or saline control mice. Furthermore, re-exposure to cocaine induced membrane hyperpolarization, but concomitantly increased excitability of MSNs from master mice, as evidenced by increased membrane input resistance, decreased depolarizing current to generate APs, and a more negative Thr (threshold) for firing. These data demonstrate functional differences in NAc MSNs after chronic contingent versus non-contingent IV cocaine administration in mice, as well as synaptic adaptations of MSNs before and after acute re-exposure to cocaine. Reversing these functional alterations in NAc could represent a rational target for the treatment of some reward-related behaviors, including drug addiction. PMID:24000958

  8. Spatial distribution of D1R- and D2R-expressing medium-sized spiny neurons differs along the rostro-caudal axis of the mouse dorsal striatum.

    PubMed

    Gangarossa, Giuseppe; Espallergues, Julie; Mailly, Philippe; De Bundel, Dimitri; de Kerchove d'Exaerde, Alban; Hervé, Denis; Girault, Jean-Antoine; Valjent, Emmanuel; Krieger, Patrik

    2013-01-01

    The striatum projection neurons are striatonigral and striatopallidal medium-sized spiny neurons (MSNs) that preferentially express D1 (D1R) and D2 (D2R) dopamine receptors, respectively. It is generally assumed that these neurons are physically intermingled, without cytoarchitectural organization although this has not been tested. To address this question we used BAC transgenic mice expressing enhanced green fluorescence (EGFP) under the control of Drd1a or Drd2 promoter and spatial point pattern statistics. We demonstrate that D1R- and D2R-expressing MSNs are randomly distributed in most of the dorsal striatum, whereas a specific region in the caudal striatum, adjacent to the GPe, lacks neurons expressing markers for indirect pathway neurons. This area comprises almost exclusively D1R-expressing MSNs. These neurons receive excitatory inputs from the primary auditory cortex and the medial geniculate thalamic nucleus and a rich dopamine innervation. This area contains cholinergic and GABAergic interneurons but apparently no D2R/A2aR modulation because no fluorescence was detected in the neuropil of Drd2-EGFP or Drd2-Cre, and Adora-Cre BAC transgenic mice crossed with reporter mice. This striatal area that expresses calbindin D28k, VGluT1 and 2, is poor in μ opiate receptors and preproenkephalin. Altogether, the differences observed in D1R-MSNs, D2R-MSNs, and interneurons densities, as well as the anatomical segregation of D1R- and D2R/A2aR-expressing MSNs suggest that there are regional differences in the organization of the striatum. PMID:23908605

  9. Spatial distribution of D1R- and D2R-expressing medium-sized spiny neurons differs along the rostro-caudal axis of the mouse dorsal striatum

    PubMed Central

    Gangarossa, Giuseppe; Espallergues, Julie; Mailly, Philippe; De Bundel, Dimitri; de Kerchove d'Exaerde, Alban; Hervé, Denis; Girault, Jean-Antoine; Valjent, Emmanuel; Krieger, Patrik

    2013-01-01

    The striatum projection neurons are striatonigral and striatopallidal medium-sized spiny neurons (MSNs) that preferentially express D1 (D1R) and D2 (D2R) dopamine receptors, respectively. It is generally assumed that these neurons are physically intermingled, without cytoarchitectural organization although this has not been tested. To address this question we used BAC transgenic mice expressing enhanced green fluorescence (EGFP) under the control of Drd1a or Drd2 promoter and spatial point pattern statistics. We demonstrate that D1R- and D2R-expressing MSNs are randomly distributed in most of the dorsal striatum, whereas a specific region in the caudal striatum, adjacent to the GPe, lacks neurons expressing markers for indirect pathway neurons. This area comprises almost exclusively D1R-expressing MSNs. These neurons receive excitatory inputs from the primary auditory cortex and the medial geniculate thalamic nucleus and a rich dopamine innervation. This area contains cholinergic and GABAergic interneurons but apparently no D2R/A2aR modulation because no fluorescence was detected in the neuropil of Drd2-EGFP or Drd2-Cre, and Adora-Cre BAC transgenic mice crossed with reporter mice. This striatal area that expresses calbindin D28k, VGluT1 and 2, is poor in μ opiate receptors and preproenkephalin. Altogether, the differences observed in D1R-MSNs, D2R-MSNs, and interneurons densities, as well as the anatomical segregation of D1R- and D2R/A2aR-expressing MSNs suggest that there are regional differences in the organization of the striatum. PMID:23908605

  10. Feedforward and Feedback inhibition in Neostriatal GABAergic Spiny Neurons

    PubMed Central

    Tepper, James M.; Wilson, Charles J.; Koós, Tibor

    2008-01-01

    There are two distinct inhibitory GABAergic circuits in the neostriatum. The feedforward circuit consists of a relatively small population of GABAergic interneurons that receives excitatory input from the neocortex and exerts monosynaptic inhibition onto striatal spiny projection neurons. The feedback circuit comprises the numerous spiny projection neurons and their interconnections via local axon collaterals. This network has long been assumed to provide the majority of striatal GABAergic inhibition and to sharpen and shape striatal output through lateral inhibition, producing increased activity in the most strongly excited spiny cells at the expense of their less strongly excited neighbors. Recent results, mostly from recording experiments of synaptically connected pairs of neurons, have revealed that the two GABAergic circuits differ markedly in terms of the total number of synapses made by each, the strength of the postsynaptic response detected at the soma, the extent of presynaptic convergence and divergence and the net effect of the activation of each circuit on the postsynaptic activity of the spiny neuron. These data have revealed that the feedforward inhibition is powerful and widespread, with spiking in a single interneuron being capable of significantly delaying or even blocking the generation of spikes in a large number of postsynaptic spiny neurons. In contrast, the postsynaptic effects of spiking in a single presynaptic spiny neuron on postsynaptic spiny neurons are weak when measured at the soma, and unable to significantly affect spike timing or generation. Further, reciprocity of synaptic connections between spiny neurons is only rarely observed. These results suggest that the bulk of the fast inhibition that has the strongest effects on spiny neuron spike timing comes from the feedforward interneuronal system whereas the axon collateral feedback system acts principally at the dendrites to control local excitability as well as the overall level of

  11. Learning intrinsic excitability in medium spiny neurons

    PubMed Central

    Scheler, Gabriele

    2014-01-01

    We present an unsupervised, local activation-dependent learning rule for intrinsic plasticity (IP) which affects the composition of ion channel conductances for single neurons in a use-dependent way. We use a single-compartment conductance-based model for medium spiny striatal neurons in order to show the effects of parameterization of individual ion channels on the neuronal membrane potential-curent relationship (activation function). We show that parameter changes within the physiological ranges are sufficient to create an ensemble of neurons with significantly different activation functions. We emphasize that the effects of intrinsic neuronal modulation on spiking behavior require a distributed mode of synaptic input and can be eliminated by strongly correlated input. We show how modulation and adaptivity in ion channel conductances can be utilized to store patterns without an additional contribution by synaptic plasticity (SP). The adaptation of the spike response may result in either "positive" or "negative" pattern learning. However, read-out of stored information depends on a distributed pattern of synaptic activity to let intrinsic modulation determine spike response. We briefly discuss the implications of this conditional memory on learning and addiction. PMID:25520776

  12. Membrane potential synchrony of simultaneously recorded striatal spiny neurons in vivo.

    PubMed

    Stern, E A; Jaeger, D; Wilson, C J

    1998-07-30

    The basal ganglia are an interconnected set of subcortical regions whose established role in cognition and motor control remains poorly understood. An important nucleus within the basal ganglia, the striatum, receives cortical afferents that convey sensorimotor, limbic and cognitive information. The activity of medium-sized spiny neurons in the striatum seems to depend on convergent input within these information channels. To determine the degree of correlated input, both below and at threshold for the generation of action potentials, we recorded intracellularly from pairs of spiny neurons in vivo. Here we report that the transitions between depolarized and hyperpolarized states were highly correlated among neurons. Within individual depolarized states, some significant synchronous fluctuations in membrane potential occurred, but action potentials were not synchronized. Therefore, although the mean afferent signal across fibres is highly correlated among striatal neurons, the moment-to-moment variations around the mean, which determine the timing of action potentials, are not. We propose that the precisely timed, synchronous component of the membrane potential signals activation of cell assemblies and enables firing to occur. The asynchronous component, with low redundancy, determines the fine temporal pattern of spikes. PMID:9697769

  13. Nitric oxide regulates synaptic transmission between spiny projection neurons

    PubMed Central

    Sagi, Yotam; Heiman, Myriam; Peterson, Jayms D.; Musatov, Sergei; Scarduzio, Mariangela; Logan, Stephen M.; Kaplitt, Michael G.; Surmeier, Dalton J.; Heintz, Nathaniel; Greengard, Paul

    2014-01-01

    Recurrent axon collaterals are a major means of communication between spiny projection neurons (SPNs) in the striatum and profoundly affect the function of the basal ganglia. However, little is known about the molecular and cellular mechanisms that underlie this communication. We show that intrastriatal nitric oxide (NO) signaling elevates the expression of the vesicular GABA transporter (VGAT) within recurrent collaterals of SPNs. Down-regulation of striatal NO signaling resulted in an attenuation of GABAergic signaling in SPN local collaterals, down-regulation of VGAT expression in local processes of SPNs, and impaired motor behavior. PKG1 and cAMP response element-binding protein are involved in the signal transduction that transcriptionally regulates VGAT by NO. These data suggest that transcriptional control of the vesicular GABA transporter by NO regulates GABA transmission and action selection. PMID:25413364

  14. 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

  15. Conditional targeting of medium spiny neurons in the striatal matrix.

    PubMed

    Reinius, Björn; Blunder, Martina; Brett, Frances M; Eriksson, Anders; Patra, Kalicharan; Jonsson, Jörgen; Jazin, Elena; Kullander, Klas

    2015-01-01

    The striatum serves as the main input to the basal ganglia, and is key for the regulation of motor behaviors, compulsion, addiction, and various cognitive and emotional states. Its deterioration is associated with degenerative disorders such as Huntington's disease. Despite its apparent anatomical uniformity, it consists of intermingled cell populations, which have precluded straightforward anatomical sub-classifications adhering to functional dissections. Approximately 95% of the striatal neurons are inhibitory projection neurons termed medium spiny neurons (MSNs). They are commonly classified according to their expression of either dopamine receptor D1 or D2, which also determines their axonal projection patterns constituting the direct and indirect pathway in the basal ganglia. Immunohistochemical patterns have further indicated compartmentalization of the striatum to the striosomes and the surrounding matrix, which integrate MSNs of both the D1 and D2 type. Here, we present a transgenic mouse line, Gpr101-Cre, with Cre recombinase activity localized to matrix D1 and D2 MSNs. Using two Gpr101-Cre founder lines with different degrees of expression in the striatum, we conditionally deleted the vesicular inhibitory amino acid transporter (VIAAT), responsible for storage of GABA and glycine in synaptic vesicles. Partial ablation of VIAAT (in ~36% of MSNs) resulted in elevated locomotor activity compared to control mice, when provoked with the monoamine reuptake inhibitor cocaine. Near complete targeting of matrix MSNs led to profoundly changed motor behaviors, which increased in severity as the mice aged. Moreover, these mice had exaggerated muscle rigidity, retarded growth, increased rate of spontaneous deaths, and defective memory. Therefore, our data provide a link between dysfunctional GABA signaling of matrix MSNs to specific behavioral alterations, which are similar to the symptoms of Huntington's disease. PMID:25870547

  16. Regulation of dendritic calcium release in striatal spiny projection neurons.

    PubMed

    Plotkin, Joshua L; Shen, Weixing; Rafalovich, Igor; Sebel, Luke E; Day, Michelle; Chan, C Savio; Surmeier, D James

    2013-11-01

    The induction of corticostriatal long-term depression (LTD) in striatal spiny projection neurons (SPNs) requires coactivation of group I metabotropic glutamate receptors (mGluRs) and L-type Ca(2+) channels. This combination leads to the postsynaptic production of endocannabinoids that act presynaptically to reduce glutamate release. Although the necessity of coactivation is agreed upon, why it is necessary in physiologically meaningful settings is not. The studies described here attempt to answer this question by using two-photon laser scanning microscopy and patch-clamp electrophysiology to interrogate the dendritic synapses of SPNs in ex vivo brain slices from transgenic mice. These experiments revealed that postsynaptic action potentials induce robust ryanodine receptor (RYR)-dependent Ca(2+)-induced-Ca(2+) release (CICR) in SPN dendritic spines. Depolarization-induced opening of voltage-gated Ca(2+) channels was necessary for CICR. CICR was more robust in indirect pathway SPNs than in direct pathway SPNs, particularly in distal dendrites. Although it did not increase intracellular Ca(2+) concentration alone, group I mGluR activation enhanced CICR and slowed Ca(2+) clearance, extending the activity-evoked intraspine transient. The mGluR modulation of CICR was sensitive to antagonism of inositol trisphosphate receptors, RYRs, src kinase, and Cav1.3 L-type Ca(2+) channels. Uncaging glutamate at individual spines effectively activated mGluRs and facilitated CICR induced by back-propagating action potentials. Disrupting CICR by antagonizing RYRs prevented the induction of corticostriatal LTD with spike-timing protocols. In contrast, mGluRs had no effect on the induction of long-term potentiation. Taken together, these results make clearer how coactivation of mGluRs and L-type Ca(2+) channels promotes the induction of activity-dependent LTD in SPNs. PMID:23966676

  17. 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…

  18. Spiny neurons of amygdala, striatum, and cortex use dendritic plateau potentials to detect network UP states

    PubMed Central

    Oikonomou, Katerina D.; Singh, Mandakini B.; Sterjanaj, Enas V.; Antic, Srdjan D.

    2014-01-01

    Spiny neurons of amygdala, striatum, and cerebral cortex share four interesting features: (1) they are the most abundant cell type within their respective brain area, (2) covered by thousands of thorny protrusions (dendritic spines), (3) possess high levels of dendritic NMDA conductances, and (4) experience sustained somatic depolarizations in vivo and in vitro (UP states). In all spiny neurons of the forebrain, adequate glutamatergic inputs generate dendritic plateau potentials (“dendritic UP states”) characterized by (i) fast rise, (ii) plateau phase lasting several hundred milliseconds, and (iii) abrupt decline at the end of the plateau phase. The dendritic plateau potential propagates toward the cell body decrementally to induce a long-lasting (longer than 100 ms, most often 200–800 ms) steady depolarization (∼20 mV amplitude), which resembles a neuronal UP state. Based on voltage-sensitive dye imaging, the plateau depolarization in the soma is precisely time-locked to the regenerative plateau potential taking place in the dendrite. The somatic plateau rises after the onset of the dendritic voltage transient and collapses with the breakdown of the dendritic plateau depolarization. We hypothesize that neuronal UP states in vivo reflect the occurrence of dendritic plateau potentials (dendritic UP states). We propose that the somatic voltage waveform during a neuronal UP state is determined by dendritic plateau potentials. A mammalian spiny neuron uses dendritic plateau potentials to detect and transform coherent network activity into a ubiquitous neuronal UP state. The biophysical properties of dendritic plateau potentials allow neurons to quickly attune to the ongoing network activity, as well as secure the stable amplitudes of successive UP states. PMID:25278841

  19. 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. PMID:19474176

  20. Numerical simulation of fractional Cable equation of spiny neuronal dendrites.

    PubMed

    Sweilam, N H; Khader, M M; Adel, M

    2014-03-01

    In this article, numerical study for the fractional Cable equation which is fundamental equations for modeling neuronal dynamics is introduced by using weighted average of finite difference methods. The stability analysis of the proposed methods is given by a recently proposed procedure similar to the standard John von Neumann stability analysis. A simple and an accurate stability criterion valid for different discretization schemes of the fractional derivative and arbitrary weight factor is introduced and checked numerically. Numerical results, figures, and comparisons have been presented to confirm the theoretical results and efficiency of the proposed method. PMID:25685492

  1. A model-based analysis of physiological properties of the striatal medium spiny neuron.

    PubMed

    Wang, Jing; Liu, Shenquan; Wang, Hongchu; Ju, Niansheng; Zeng, Yanjun

    2015-12-01

    As the principal cell of the striatum, medium spiny neurons (MSNs) are closely associated with various motor dysfunctional diseases. In this paper, we describe an electric compartment model constructed in NEURON with a realistic morphology. Based on a 554-compartment computational model, we researched the influence of external current stimuli, different ions conductance, and the removal of partial dendrites on the physiological properties of the MSN. The main results are the following: (1) in the case of external current stimuli, various firing patterns appear in the MSN and the model produces a clear period-adding bifurcation phenomenon; (2) the effect of distinct types of ion channels vary and significant differences in discharge rhythm exist even among ion channels of the same type; (3) the closer the removed dendrite was to the soma, the larger the impact this had on the discharge pattern of the MSN. PMID:26923577

  2. 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

  3. Inhibition of Hyperpolarization-Activated Cation Current in Medium-Sized DRG Neurons Contributed to the Antiallodynic Effect of Methylcobalamin in the Rat of a Chronic Compression of the DRG

    PubMed Central

    Zhang, Ming; Han, Wenjuan; Zheng, Jianyong; Meng, Fancheng; Jiao, Xiying; Hu, Sanjue; Xu, Hui

    2015-01-01

    Recently several lines of evidence demonstrated that methylcobalamin (MeCbl) might have potential analgesic effect in experimental and clinical studies. However, it was reported that MeCbl had no effect on treating lumbar spinal stenosis induced pain. Thus, the effects of short-term and long-term administration of MeCbl were examined in the chronic compression of dorsal root ganglion (CCD) model. We found that mechanical allodynia was significantly inhibited by a continuous application of high dose and a single treatment of a super high dose of MeCbl. Little is known about mechanisms underlying the analgesia of MeCbl. We examined the effect of MeCbl on the spontaneous activity (SA), the excitability, and hyperpolarization-activated nonselective cation ion current in compressed medium-sized dorsal root ganglion (DRG) neurons using extracellular single fiber recording in vivo and whole-cell patch clamp in vitro. We found that MeCbl significantly inhibited the SA of A-type sensory neurons in a dose-dependent manner and inhibited the excitability of medium-sized DRG neurons. In addition, MeCbl also decreased Ih current density in injured medium-sized DRG neurons. Our results proved that MeCbl might exert an analgesic effect through the inhibition Ih current and then might inhibit the hyperexcitability of primary sensory neurons under neuropathic pain state. PMID:26101670

  4. Subcolumnar dendritic and axonal organization of spiny stellate and star pyramid neurons within a barrel in rat somatosensory cortex.

    PubMed

    Egger, Veronica; Nevian, Thomas; Bruno, Randy M

    2008-04-01

    Excitatory neurons at the level of cortical layer 4 in the rodent somatosensory barrel field often display a strong eccentricity in comparison with layer 4 neurons in other cortical regions. In rat, dendritic symmetry of the 2 main excitatory neuronal classes, spiny stellate and star pyramid neurons (SSNs and SPNs), was quantified by an asymmetry index, the dendrite-free angle. We carefully measured shrinkage and analyzed its influence on morphological parameters. SSNs had mostly eccentric morphology, whereas SPNs were nearly radially symmetric. Most asymmetric neurons were located near the barrel border. The axonal projections, analyzed at the level of layer 4, were mostly restricted to a single barrel except for those of 3 interbarrel projection neurons. Comparing voxel representations of dendrites and axon collaterals of the same neuron revealed a close overlap of dendritic and axonal fields, more pronounced in SSNs versus SPNs and considerably stronger in spiny L4 neurons versus extragranular pyramidal cells. These observations suggest that within a barrel dendrites and axons of individual excitatory cells are organized in subcolumns that may confer receptive field properties such as directional selectivity to higher layers, whereas the interbarrel projections challenge our view of barrels as completely independent processors of thalamic input. PMID:17656622

  5. HIV-1 Transgenic Female Rat: Synaptodendritic Alterations of Medium Spiny Neurons in the Nucleus Accumbens

    PubMed Central

    Roscoe, Robert F.; Mactutus, Charles F.

    2015-01-01

    HIV-1 associated neurocognitive deficits are increasing in prevalence, although the neuronal basis for these deficits is unclear. HIV-1 Tg rats constitutively express 7 of 9 HIV-associated proteins, and may be useful for studying the neuropathological substrates of HIV-1 associated neurocognitive disorders (HAND). In this study, adult female HIV-1 Tg rats and F344 control rats had similar growth rates, estrous cyclicity and startle reflex inhibition to a visual prepulse stimulus. Medium spiny neurons (MSNs) in the nucleus accumbens (NAcc) were ballistically-labeled utilizing the indocarbocyanine dye DiI. The branching complexity of MSNs in the NAcc was significantly decreased in HIV-1 Tg rats, relative to controls; moreover, the shorter length and decreased volume of dendritic spines, but unchanged head diameter, in HIV-1 Tg rats suggested a reduction of longer spines and an increase in shorter, less projected spines, indicating a population shift to a more immature spine phenotype. Collectively, these results from HIV-1 Tg female rats indicated significant synaptodendritic alterations of MSNs in the NAcc occur as a consequence of chronic, low-level, exposure to HIV-1 associated proteins. PMID:25037595

  6. Levodopa-Induced Dyskinesia Is Related to Indirect Pathway Medium Spiny Neuron Excitotoxicity: A Hypothesis Based on an Unexpected Finding

    PubMed Central

    Ivanova, Svetlana A.

    2016-01-01

    A serendipitous pharmacogenetic finding links the vulnerability to developing levodopa-induced dyskinesia to the age of onset of Huntington's disease. Huntington's disease is caused by a polyglutamate expansion of the protein huntingtin. Aberrant huntingtin is less capable of binding to a member of membrane-associated guanylate kinase family (MAGUKs): postsynaptic density- (PSD-) 95. This leaves more PSD-95 available to stabilize NR2B subunit carrying NMDA receptors in the synaptic membrane. This results in increased excitotoxicity for which particularly striatal medium spiny neurons from the indirect extrapyramidal pathway are sensitive. In Parkinson's disease the sensitivity for excitotoxicity is related to increased oxidative stress due to genetically determined abnormal metabolism of dopamine or related products. This probably also increases the sensitivity of medium spiny neurons for exogenous levodopa. Particularly the combination of increased oxidative stress due to aberrant dopamine metabolism, increased vulnerability to NMDA induced excitotoxicity, and the particular sensitivity of indirect pathway medium spiny neurons for this excitotoxicity may explain the observed increased prevalence of levodopa-induced dyskinesia. PMID:27144051

  7. Form, function and intracortical projections of spiny neurones in the striate visual cortex of the cat.

    PubMed Central

    Martin, K A; Whitteridge, D

    1984-01-01

    We have studied the neuronal circuitry and structure-function relationships of single neurones in the striate visual cortex of the cat using a combination of electrophysiological and anatomical techniques. Glass micropipettes filled with horseradish peroxidase were used to record extracellularly from single neurones. After studying the receptive field properties, the afferent inputs of the neurones were studied by determining their latency of response to electrical stimulation at different positions along the optic pathway. Some cells were thus classified as receiving a mono- or polysynaptic input from afferents of the lateral geniculate nucleus (l.g.n.), via X- or Y-like retinal ganglion cells. Two striking correlations were found between dendritic morphology and receptive field type. All spiny stellate cells, and all star pyramidal cells in layer 4A, had receptive fields with spatially separate on and off subfields (S-type receptive fields). All the identified afferent input to these, the major cell types in layer 4, was monosynaptic from X- or Y-like afferents. Neurones receiving monosynaptic X- or Y-like input were not strictly segregated in layer 4 and the lower portion of layer 3. Nevertheless the X- and Y-like l.g.n. fibres did not converge on any of the single neurones so far studied. Monosynaptic input from the l.g.n. afferents was not restricted to cells lying within layers 4 and 6, the main termination zones of the l.g.n. afferents, but was also received by cells lying in layers 3 and 5. The projection pattern of cells receiving monosynaptic input differed widely, depending on the laminar location of the cell soma. This suggests the presence of a number of divergent paths within the striate cortex. Cells receiving indirect input from the l.g.n. afferents were located mainly within layers 2, 3 and 5. Most pyramidal cells in layer 3 had axons projecting out of the striate cortex, while many axons of the layer 5 pyramids did not. The layer 5 cells showed

  8. Timing and location of synaptic inputs determine modes of subthreshold integration in striatal medium spiny neurons.

    PubMed

    Carter, Adam G; Soler-Llavina, Gilberto J; Sabatini, Bernardo L

    2007-08-15

    Medium spiny neurons (MSNs) are the principal cells of the striatum and perform a central role in sensorimotor processing. MSNs must integrate many excitatory inputs located across their dendrites to fire action potentials and enable striatal function. However, the dependence of synaptic responses on the temporal and spatial distribution of these inputs remains unknown. Here, we use whole-cell recordings, two-photon microscopy, and two-photon glutamate uncaging to examine subthreshold synaptic integration in MSNs from acute rat brain slices. We find that synaptic responses can summate sublinearly, linearly, or supralinearly depending on the spatiotemporal pattern of activity. Repetitive activity at single inputs leads to sublinear summation, reflecting long-lived AMPA receptor desensitization. In contrast, asynchronous activity at multiple inputs generates linear summation, with synapses on neighboring spines functioning independently. Finally, synchronous activity at multiple inputs triggers supralinear summation at depolarized potentials, reflecting activation of NMDA receptors and L-type calcium channels. Thus, the properties of subthreshold integration in MSNs are determined by the distribution of synaptic inputs and the differential activation of multiple postsynaptic conductances. PMID:17699678

  9. Ethanol Disinhibits Dorsolateral Striatal Medium Spiny Neurons Through Activation of A Presynaptic Delta Opioid Receptor.

    PubMed

    Patton, Mary H; Roberts, Bradley M; Lovinger, David M; Mathur, Brian N

    2016-06-01

    The dorsolateral striatum mediates habit formation, which is expedited by exposure to alcohol. Across species, alcohol exposure disinhibits the DLS by dampening GABAergic transmission onto this structure's principal medium spiny projection neurons (MSNs), providing a potential mechanistic basis for habitual alcohol drinking. However, the molecular and circuit components underlying this disinhibition remain unknown. To examine this, we used a combination of whole-cell patch-clamp recordings and optogenetics to demonstrate that ethanol potently depresses both MSN- and fast-spiking interneuron (FSI)-MSN GABAergic synaptic transmission in the DLS. Concentrating on the powerfully inhibitory FSI-MSN synapse, we further show that acute exposure of ethanol (50 mM) to striatal slices activates delta opioid receptors that reside on FSI axon terminals and negatively couple to adenylyl cyclase to induce a long-term depression of GABA release onto both direct and indirect pathway MSNs. These findings elucidate a mechanism through which ethanol may globally disinhibit the DLS. PMID:26758662

  10. 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

  11. 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

  12. Consistent Injury to Medium Spiny Neurons and White Matter in the Mouse Striatum after Prolonged Transient Global Cerebral Ischemia

    PubMed Central

    Yoshioka, Hideyuki; Niizuma, Kuniyasu; Katsu, Masataka; Sakata, Hiroyuki; Okami, Nobuya

    2011-01-01

    Abstract A reproducible transient global cerebral ischemia (tGCI) mouse model has not been fully established. Although striatal neurons and white matter are recognized to be vulnerable to ischemia, their injury after tGCI in mice has not been elucidated. The purpose of this study was to evaluate injuries to striatal neurons and white matter after tGCI in C57BL/6 mice, and to develop a reproducible tGCI model. Male C57BL/6 mice were subjected to tGCI by bilateral common carotid artery occlusion (BCCAO). Mice whose cortical cerebral blood flow after BCCAO decreased to less than 13% of the pre-ischemic value were used. Histological analysis showed that at 3 days after 22 min of BCCAO, striatal neurons were injured more consistently than those in other brain regions. Quantitative analysis of cytochrome c release into the cytosol and DNA fragmentation in the striatum showed consistent injury to the striatum. Immunohistochemistry and Western blot analysis revealed that DARPP-32-positive medium spiny neurons, the majority of striatal neurons, were the most vulnerable among the striatal neuronal subpopulations. The striatum (especially medium spiny neurons) was susceptible to oxidative stress after tGCI, which is probably one of the mechanisms of vulnerability. SMI-32 immunostaining showed that white matter in the striatum was also consistently injured 3 days after 22 min of BCCAO. We thus suggest that this is a tGCI model using C57BL/6 mice that consistently produces neuronal and white matter injury in the striatum by a simple technique. This model can be highly applicable for elucidating molecular mechanisms in the brain after global ischemia. PMID:21309724

  13. Differential dopaminergic regulation of inwardly rectifying potassium channel mediated subthreshold dynamics in striatal medium spiny neurons.

    PubMed

    Zhao, Bo; Zhu, Junling; Dai, Dongqing; Xing, Junling; He, Jiahou; Fu, Zhanyan; Zhang, Lei; Li, Zhuyi; Wang, Wenting

    2016-08-01

    The dorsal striatum plays a key role in motor control and cognitive processes. Proper functioning of the striatum relies on the fine dynamic balance between the direct pathway projection medium spiny neurons (MSNs) that express D1 dopamine receptor (D1 MSNs) and indirect pathway projection MSNs that express D2 dopamine receptor (D2 MSNs). The inwardly rectifying K(+) channels (Kir), which express on both D1 and D2 MSNs, participate in the subthreshold dynamics including the membrane resonance and dendritic integration. However, it remains unclear whether dopamine differentially regulates Kir mediated subthreshold dynamics in two subtypes MSNs. Using transgenic mice that express either tdTomato in D1 MSNs or eGFP in D2 MSNs, we explored the Kir mediated subthreshold dynamics in D1 or D2 MSNs with whole cell patch clamp recording in acute brain slices. We found that D1 receptor agonist increased the Kir current while D2 receptor activation decreased the Kir conductance. The dopamine regulation of the Kir enhanced the resonant frequency and reduced the resonant impedance of D1 MSNs. The converse is ture for D2 MSNs. It also caused an opposing effect on dendritic integration between D1 and D2 MSNs, which can promote stability of the two pathways. The D1 receptor activation modulated Kir through cAMP-PKA signaling, whereas the D2 receptor modulated Kir through PLC-PKC signaling. Our findings demonstrated the differential dopaminergic regulation role of Kir, which mediates distinct subthreshold dynamics, and thus, contributes to the role of dopamine in fine tuning the balance of the striatal direct and indirect pathway activities. PMID:27018450

  14. Psychoactive drugs and regulation of the cAMP/PKA/DARPP-32 cascade in striatal medium spiny neurons.

    PubMed

    Borgkvist, Anders; Fisone, Gilberto

    2007-01-01

    Changes in activity of the medium spiny neurons (MSNs) of dorsal and ventral striatum result in alterations of motor performance, ranging from rapid increases or decreases in locomotor activity, to long-term modifications of motor behaviours. In the dorsal striatum, MSNs can be distinguished based on the organization of their connectivity to substantia nigra pars reticulata (SNpr) and internal segment of the globus pallidus (GPi), which, in turn, control thalamocortical neurons. Approximately half of the MSNs project directly to SNpr and GPi, their activation leading to disinhibition of thalamocortical neurons and increased motor activity. The other subpopulation of MSNs connects to SNpr and GPi indirectly and when activated promotes inhibition of thalamocortical neurons, thereby reducing motor activity. The dopamine- and cAMP-regulated phosphoprotein of 32 kDa (DARPP-32) is a modulator of the cAMP signalling pathway, highly expressed in MSNs. This review discusses the regulation of DARPP-32 exerted by psychoactive substances in specific populations of striatal projection neurons and its involvement in short- and long-term motor responses. PMID:16730373

  15. 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

  16. Mechanisms underlying odorant-induced and spontaneous calcium signals in olfactory receptor neurons of spiny lobsters, Panulirus argus.

    PubMed

    Tadesse, Tizeta; Derby, Charles D; Schmidt, Manfred

    2014-01-01

    We determined if a newly developed antennule slice preparation allows studying chemosensory properties of spiny lobster olfactory receptor neurons under in situ conditions with Ca(2+) imaging. We show that chemical stimuli reach the dendrites of olfactory receptor neurons but not their somata, and that odorant-induced Ca(2+) signals in the somata are sufficiently stable over time to allow stimulation with a substantial number of odorants. Pharmacological manipulations served to elucidate the source of odorant-induced Ca(2+) transients and spontaneous Ca(2+) oscillations in the somata of olfactory receptor neurons. Both Ca(2+) signals are primarily mediated by an influx of extracellular Ca(2+) through voltage-activated Ca(2+) channels that can be blocked by CoCl2 and the L-type Ca(2+) channel blocker verapamil. Intracellular Ca(2+) stores contribute little to odorant-induced Ca(2+) transients and spontaneous Ca(2+) oscillations. The odorant-induced Ca(2+) transients as well as the spontaneous Ca(2+) oscillations depend on action potentials mediated by Na(+) channels that are largely TTX-insensitive but blocked by the local anesthetics tetracaine and lidocaine. Collectively, these results corroborate the conclusion that odorant-induced Ca(2+) transients and spontaneous Ca(2+) oscillations in the somata of olfactory receptor neurons closely reflect action potential activity associated with odorant-induced phasic-tonic responses and spontaneous bursting, respectively. Therefore, both types of Ca(2+) signals represent experimentally accessible proxies of spiking. PMID:24178131

  17. 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. PMID:25752326

  18. The striatal balancing act in drug addiction: distinct roles of direct and indirect pathway medium spiny neurons.

    PubMed

    Lobo, Mary Kay; Nestler, Eric J

    2011-01-01

    The striatum plays a key role in mediating the acute and chronic effects of addictive drugs, with drugs of abuse causing long-lasting molecular and cellular alterations in both dorsal striatum and nucleus accumbens (ventral striatum). Despite the wealth of research on the biological actions of abused drugs in striatum, until recently, the distinct roles of the striatum's two major subtypes of medium spiny neurons (MSNs) in drug addiction remained elusive. Recent advances in cell-type-specific technologies, including fluorescent reporter mice, transgenic, or knockout mice, and viral-mediated gene transfer, have advanced the field toward a more comprehensive understanding of the two MSN subtypes in the long-term actions of drugs of abuse. Here we review progress in defining the distinct molecular and functional contributions of the two MSN subtypes in mediating addiction. PMID:21811439

  19. The Striatal Balancing Act in Drug Addiction: Distinct Roles of Direct and Indirect Pathway Medium Spiny Neurons

    PubMed Central

    Lobo, Mary Kay; Nestler, Eric J.

    2011-01-01

    The striatum plays a key role in mediating the acute and chronic effects of addictive drugs, with drugs of abuse causing long-lasting molecular and cellular alterations in both dorsal striatum and nucleus accumbens (ventral striatum). Despite the wealth of research on the biological actions of abused drugs in striatum, until recently, the distinct roles of the striatum’s two major subtypes of medium spiny neurons (MSNs) in drug addiction remained elusive. Recent advances in cell-type-specific technologies, including fluorescent reporter mice, transgenic, or knockout mice, and viral-mediated gene transfer, have advanced the field toward a more comprehensive understanding of the two MSN subtypes in the long-term actions of drugs of abuse. Here we review progress in defining the distinct molecular and functional contributions of the two MSN subtypes in mediating addiction. PMID:21811439

  20. 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

  1. The Dopamine D1–D2 Receptor Heteromer in Striatal Medium Spiny Neurons: Evidence for a Third Distinct Neuronal Pathway in Basal Ganglia

    PubMed Central

    Perreault, Melissa L.; Hasbi, Ahmed; O’Dowd, Brian F.; George, Susan R.

    2011-01-01

    Dopaminergic signaling within the basal ganglia has classically been thought to occur within two distinct neuronal pathways; the direct striatonigral pathway which contains the dopamine D1 receptor and the neuropeptides dynorphin (DYN) and substance P, and the indirect striatopallidal pathway which expresses the dopamine D2 receptor and enkephalin (ENK). A number of studies have also shown, however, that D1 and D2 receptors can co-exist within the same medium spiny neuron and emerging evidence indicates that these D1/D2-coexpressing neurons, which also express DYN and ENK, may comprise a third neuronal pathway, with representation in both the striatonigral and striatopallidal projections of the basal ganglia. Furthermore, within these coexpressing neurons it has been shown that the dopamine D1 and D2 receptor can form a novel and pharmacologically distinct receptor complex, the dopamine D1–D2 receptor heteromer, with unique signaling properties. This is indicative of a functionally unique role for these neurons in brain. The aim of this review is to discuss the evidence in support of a novel third pathway coexpressing the D1 and D2 receptor, to discuss the potential relevance of this pathway to basal ganglia signaling, and to address its potential value, and that of the dopamine D1–D2 receptor heteromer, in the search for new therapeutic strategies for disorders involving dopamine neurotransmission. PMID:21747759

  2. 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

  3. BDNF and Huntingtin protein modifications by manganese: implications for striatal medium spiny neuron pathology in manganese neurotoxicity.

    PubMed

    Stansfield, Kirstie H; Bichell, Terry Jo; Bowman, Aaron B; Guilarte, Tomás R

    2014-12-01

    High levels of manganese (Mn) exposure decrease striatal medium spiny neuron (MSN) dendritic length and spine density, but the mechanism(s) are not known. The Huntingtin (HTT) gene has been functionally linked to cortical brain-derived neurotrophic factor (BDNF) support of striatal MSNs via phosphorylation at serine 421. In Huntington's disease, pathogenic CAG repeat expansions of HTT decrease synthesis and disrupt transport of cortical-striatal BDNF, which may contribute to disease, and Mn is a putative environmental modifier of Huntington's disease pathology. Thus, we tested the hypothesis that changes in MSN dendritic morphology Mn due to exposure are associated with decreased BDNF levels and alterations in Htt protein. We report that BDNF levels are decreased in the striatum of Mn-exposed non-human primates and in the cerebral cortex and striatum of mice exposed to Mn. Furthermore, proBDNF and mature BDNF concentrations in primary cortical and hippocampal neuron cultures were decreased by exposure to Mn confirming the in vivo findings. Mn exposure decreased serine 421 phosphorylation of Htt in cortical and hippocampal neurons and increased total Htt levels. These data strongly support the hypothesis that Mn-exposure-related MSN pathology is associated with decreased BDNF trophic support via alterations in Htt. PMID:25099302

  4. BDNF and Huntingtin protein modifications by Manganese: Implications for striatal medium spiny neuron pathology in manganese neurotoxicity

    PubMed Central

    Stansfield, Kirstie H.; Bichell, Terry Jo; Bowman, Aaron B.; Guilarte, Tomás R.

    2014-01-01

    High levels of manganese (Mn) exposure decreases striatal medium spiny neuron (MSN) dendritic length and spine density, but the mechanism(s) are not known. The Huntingtin (HTT) gene has been functionally linked to cortical brain-derived neurotrophic factor (BDNF) support of striatal MSNs via phosphorylation at serine 421 (S421). In Huntington's disease, pathogenic CAG-repeat expansions of HTT decrease synthesis and disrupt transport of cortical-striatal BDNF contributing to disease, and Mn is a putative environmental modifier of Huntington's disease pathology. Thus, we tested the hypothesis that changes in MSN dendritic morphology due to Mn exposure are associated with decreased BDNF levels and alterations in Htt protein. We report that BDNF levels are decreased in the striatum of Mn-exposed non-human primates and in the cerebral cortex and striatum of mice exposed to Mn. Further, proBDNF and mature BDNF concentrations in primary cortical and hippocampal neuron cultures were decreased by exposure to Mn confirming the in vivo findings. Mn exposure decreased S421 phosphorylation of Htt in cortical and hippocampal neurons and increased total Htt levels. These data strongly support the hypothesis that Mn-exposure related MSN pathology is associated with decreased BDNF trophic support via alterations in Htt. PMID:25099302

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

    PubMed

    Willett, Jaime A; Will, Tyler; Hauser, Caitlin A; Dorris, David M; Cao, Jinyan; Meitzen, John

    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

  6. 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

  7. 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

  8. Optogenetics reveals a role for accumbal medium spiny neurons expressing dopamine D2 receptors in cocaine-induced behavioral sensitization

    PubMed Central

    Song, Shelly Sooyun; Kang, Byeong Jun; Wen, Lei; Lee, Hyo Jin; Sim, Hye-ri; Kim, Tae Hyong; Yoon, Sehyoun; Yoon, Bong-June; Augustine, George J.; Baik, Ja-Hyun

    2014-01-01

    Long-lasting, drug-induced adaptations within the nucleus accumbens (NAc) have been proposed to contribute to drug-mediated addictive behaviors. Here we have used an optogenetic approach to examine the role of NAc medium spiny neurons (MSNs) expressing dopamine D2 receptors (D2Rs) in cocaine-induced behavioral sensitization. Adeno-associated viral vectors encoding channelrhodopsin-2 (ChR2) were delivered into the NAc of D2R-Cre transgenic mice. This allowed us to selectively photostimulate D2R-MSNs in NAc. D2R-MSNs form local inhibitory circuits, because photostimulation of D2R-MSN evoked inhibitory postsynaptic currents (IPSCs) in neighboring MSNs. Photostimulation of NAc D2R-MSN in vivo affected neither the initiation nor the expression of cocaine-induced behavioral sensitization. However, photostimulation during the drug withdrawal period attenuated expression of cocaine-induced behavioral sensitization. These results show that D2R-MSNs of NAc play a key role in withdrawal-induced plasticity and may contribute to relapse after cessation of drug abuse. PMID:25352792

  9. FoxP1 marks medium spiny neurons from precursors to maturity and is required for their differentiation.

    PubMed

    Precious, S V; Kelly, C M; Reddington, A E; Vinh, N N; Stickland, R C; Pekarik, V; Scherf, C; Jeyasingham, R; Glasbey, J; Holeiter, M; Jones, L; Taylor, M V; Rosser, A E

    2016-08-01

    Identifying the steps involved in striatal development is important both for understanding the striatum in health and disease, and for generating protocols to differentiate striatal neurons for regenerative medicine. The most prominent neuronal subtype in the adult striatum is the medium spiny projection neuron (MSN), which constitutes more than 85% of all striatal neurons and classically expresses DARPP-32. Through a microarray study of genes expressed in the whole ganglionic eminence (WGE: the developing striatum) in the mouse, we identified the gene encoding the transcription factor Forkhead box protein P1 (FoxP1) as the most highly up-regulated gene, thus providing unbiased evidence for the association of FoxP1 with MSN development. We also describe the expression of FoxP1 in the human fetal brain over equivalent gestational stages. FoxP1 expression persisted through into adulthood in the mouse brain, where it co-localised with all striatal DARPP-32 positive projection neurons and a small population of DARPP-32 negative cells. There was no co-localisation of FoxP1 with any interneuron markers. FoxP1 was detectable in primary fetal striatal cells following dissection, culture, and transplantation into the adult lesioned striatum, demonstrating its utility as an MSN marker for transplantation studies. Furthermore, DARPP-32 expression was absent from FoxP1 knock-out mouse WGE differentiated in vitro, suggesting that FoxP1 is important for the development of DARPP-32-positive MSNs. In summary, we show that FoxP1 labels MSN precursors prior to the expression of DARPP-32 during normal development, and in addition suggest that FoxP1 labels a sub-population of MSNs that are not co-labelled by DARPP-32. We demonstrate the utility of FoxP1 to label MSNs in vitro and following neural transplantation, and show that FoxP1 is required for DARPP-32 positive MSN differentiation in vitro. PMID:27154297

  10. Medium-size-vessel vasculitis

    PubMed Central

    Eleftheriou, Despina; Brogan, Paul A.

    2009-01-01

    Medium-size-artery vasculitides do occur in childhood and manifest, in the main, as polyarteritis nodosa (PAN), cutaneous PAN and Kawasaki disease. Of these, PAN is the most serious, with high morbidity and not inconsequential mortality rates. New classification criteria for PAN have been validated that will have value in epidemiological studies and clinical trials. Renal involvement is common and recent therapeutic advances may result in improved treatment options. Cutaneous PAN is a milder disease characterised by periodic exacerbations and often associated with streptococcal infection. There is controversy as to whether this is a separate entity or part of the systemic PAN spectrum. Kawasaki disease is an acute self-limiting systemic vasculitis, the second commonest vasculitis in childhood and the commonest cause of childhood-acquired heart disease. Renal manifestations occur and include tubulointerstitial nephritis and renal failure. An infectious trigger and a genetic predisposition seem likely. Intravenous immunoglobulin (IV-Ig) and aspirin are effective therapeutically, but in resistant cases, either steroid or infliximab have a role. Greater understanding of the pathogenetic mechanisms involved in these three types of vasculitis and better long-term follow-up data will lead to improved therapy and prediction of prognosis. PMID:19946711

  11. Susceptibility of striatal neurons to excitotoxic injury correlates with basal levels of Bcl-2 and the induction of P53 and c-Myc immunoreactivity.

    PubMed

    Liang, Zhong-Qin; Wang, Xiao-Xia; Wang, Yumei; Chuang, De-Maw; DiFiglia, Marian; Chase, Thomas N; Qin, Zheng-Hong

    2005-11-01

    The present studies evaluated the potential contribution of Bcl-2, p53, and c-Myc to the differential vulnerability of striatal neurons to the excitotoxin quinolinic acid (QA). In normal rat striatum, Bcl-2 immunoreactivity (Bcl-2-i) was most intense in large aspiny interneurons including choline acetyltransferase positive (CAT+) and parvalbumin positive (PARV+) neurons, but low in a majority of medium-sized neurons. In human brain, intense Bcl-2-i was seen in large striatal neurons but not in medium-sized spiny projection neurons. QA produced degeneration of numerous medium-sized neurons, but not those enriched in Bcl-2-i. Many Bcl-2-i-enriched interneurons including those with CAT+ and PARV+ survived QA injection, while medium-sized neurons labeled for calbindin D-28K (CAL D-28+) did not. In addition, proapoptotic proteins p53-i and c-Myc-i were robustly induced in medium-sized neurons, but not in most large neurons. The selective vulnerability of striatal medium spiny neurons to degeneration in a rodent model of Huntington's disease appears to correlate with their low levels of Bcl-2-i and high levels of induced p53-i and c-Myc-i. PMID:15922606

  12. 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

    2014-09-01

    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. PMID:25037227

  13. Involvement of the Striatal Medium Spiny Neurons of the Direct Pathway in the Motor Stimulant Effects of Phencyclidine

    PubMed Central

    Bonito-Oliva, Alessandra; DuPont, Caitlin; Madjid, Nather; Ögren, Sven Ove

    2016-01-01

    Background: The psychotomimetic phencyclidine (PCP) produces behavioral symptoms similar to those observed in schizophrenia, accompanied by increased motor activity. The dopamine and adenosine 3’,5’-cyclic monophosphate-regulated phosphoprotein of 32kDa (DARPP-32) is enriched in the medium spiny neurons (MSNs) of the striatum and has been implicated in the actions of PCP. We examined the effects of deletion of DARPP-32 in distinct populations of striatal MSNs, on the ability of PCP to induce motor activation and memory deficit. Methods: The effects of PCP were examined in mice with conditional knockout of DARPP-32 in the MSNs of the direct, or indirect pathway. DARPP-32 phosphorylation was determined by Western blotting. The motor stimulant effects of PCP were determined by measuring locomotion following acute and chronic administration. Memory deficit was evaluated using the passive avoidance test. Results: Loss of DARPP-32 in direct MSNs prevents PCP-induced phosphorylation and abolishes the motor stimulation effects of PCP. In contrast, lack of DARPP-32 in indirect MSNs does not affect the ability of PCP to promote DARPP-32 phosphorylation and to increase motor activity. The impairment in passive avoidance induced by PCP is independent of the expression of DARPP-32 in direct or indirect MSNs. Conclusions: The increase in DARPP-32 phosphorylation induced by PCP occurs selectively in the MSNs of the direct pathway, which are also specifically involved in the motor stimulant effects of this drug. The memory deficit induced by PCP is not linked to the expression of DARPP-32 in striatal MSNs. PMID:26657176

  14. Partial mitochondrial inhibition causes striatal dopamine release suppression and medium spiny neuron depolarization via H2O2 elevation, not ATP depletion.

    PubMed

    Bao, Li; Avshalumov, Marat V; Rice, Margaret E

    2005-10-26

    Mitochondrial dysfunction is a potential causal factor in Parkinson's disease. We show here that acute exposure to the mitochondrial complex I inhibitor rotenone (30-100 nM; 30 min) causes concentration-dependent suppression of single-pulse evoked dopamine (DA) release monitored in real time with carbon-fiber microelectrodes in guinea pig striatal slices, with no effect on DA content. Suppression of DA release was prevented by the sulfonylurea glibenclamide, implicating ATP-sensitive K+ (KATP) channels; however, tissue ATP was unaltered. Because KATP channels can be activated by hydrogen peroxide (H2O2), as well as by low ATP, we examined the involvement of rotenone-enhanced H2O2 generation. Confirming an essential role for H2O2, the inhibition of DA release by rotenone was prevented by catalase, a peroxide-scavenging enzyme. Striatal H2O2 generation during rotenone exposure was examined in individual medium spiny neurons using fluorescence imaging with dichlorofluorescein (DCF). An increase in intracellular H2O2 levels followed a similar time course to that of DA release suppression and was accompanied by cell membrane depolarization, decreased input resistance, and increased excitability. Extracellular catalase markedly attenuated the increase in DCF fluorescence and prevented rotenone-induced effects on membrane properties; membrane changes were also largely prevented by flufenamic acid, a blocker of transient receptor potential (TRP) channels. Thus, partial mitochondrial inhibition can cause functional DA denervation via H2O2 and KATP channels, without DA or ATP depletion. Furthermore, amplified H2O2 levels and TRP channel activation in striatal spiny neurons indicate potential sources of damage in these cells. Overall, these novel factors could contribute to parkinsonian motor deficits and neuronal degeneration caused by mitochondrial dysfunction. PMID:16251452

  15. Impact of Dendritic Spine Preservation in Medium Spiny Neurons on Dopamine Graft Efficacy and the Expression of Dyskinesias in Parkinsonian Rats

    PubMed Central

    Soderstrom, Katherine E.; O’Malley, Jennifer A.; Levine, Nathan D.; Sortwell, Caryl E.; Collier, Timothy J.; Steece-Collier, Kathy

    2010-01-01

    Dopamine deficiency associated with Parkinson’s disease (PD) results in numerous changes in striatal transmitter function and neuron morphology. Specifically, there is marked atrophy of dendrites and dendritic spines on striatal medium spiny neurons (MSN), primary targets of inputs from nigral dopamine and cortical glutamate neurons, in advanced PD and rodent models of severe dopamine depletion. Dendritic spine loss occurs via dysregulation of intraspine Cav1.3 L-type Ca2+ channels and can be prevented, in animal models, by administration of the calcium channel antagonist, nimodipine. The impact of MSN dendritic spine loss in the parkinsonian striatum on dopamine neuron graft therapy remains unexamined. Using unilaterally parkinsonian Sprague Dawley rats, we tested the hypothesis that MSN dendritic spine preservation through administration of nimodipine would result in improved therapeutic benefit and diminished graft-induced behavioral abnormalities in rats grafted with embryonic ventral midbrain cells. Analysis of rotational asymmetry and spontaneous forelimb use in the cylinder task found no significant effect of dendritic spine preservation in grafted rats. However, analyses of vibrissae-induced forelimb use, levodopa-induced dyskinesias, and graft-induced dyskinesias showed significant improvement in rats with dopamine grafts associated with preserved striatal dendritic spine density. Nimodipine treatment in this model did not impact dopamine graft survival but allowed for increased graft reinnervation of striatum. Taken together, these results demonstrate that even with grafting suboptimal numbers of cells, maintaining normal spine density on target MSNs results in overall superior behavioral efficacy of dopamine grafts. PMID:20105237

  16. 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

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

    PubMed

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

    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

  18. 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

  19. Selective expression of a dominant-negative type Iα PKA regulatory subunit in striatal medium spiny neurons impairs gene expression and leads to reduced feeding and locomotor activity.

    PubMed

    Yang, Linghai; Gilbert, Merle L; Zheng, Ruimao; McKnight, G Stanley

    2014-04-01

    Striatal medium spiny neurons (MSNs) mediate many of the physiological effects of dopamine, including the regulation of feeding and motor behaviors. Dopaminergic inputs from the midbrain modulate MSN excitability through pathways that involve cAMP and protein kinase A (PKA), but the physiological role of specific PKA isoforms in MSN neurons remains poorly understood. One of the major PKA regulatory (R) subunit isoforms expressed in MSNs is RIIβ, which localizes the PKA holoenzyme primarily to dendrites by interaction with AKAP5 and other scaffolding proteins. However, RI (RIα and RIβ) subunits are also expressed in MSNs and the RI holoenzyme has a weaker affinity for most scaffolding proteins and tends to localize in the cell body. We generated mice with selective expression of a dominant-negative RI subunit (RIαB) in striatal MSNs and show that this dominant-negative RIαB localizes to the cytoplasm and specifically inhibits type I PKA activity in the striatum. These mice are normal at birth; however, soon after weaning they exhibit growth retardation and the adult mice are hypophagic, lean, and resistant to high-fat diet-induced hyperphagia and obesity. The RIαB-expressing mice also exhibit decreased locomotor activity and decreased dopamine-regulated CREB phosphorylation and c-fos gene expression in the striatum. Our results demonstrate a critical role for cytoplasmic RI-PKA holoenzyme in gene regulation and the overall physiological function of MSNs. PMID:24695708

  20. Action selection in a possible model of striatal medium spiny neuron dysfunction: behavioral and EEG data in a patient with benign hereditary chorea.

    PubMed

    Beste, Christian; Saft, Carsten

    2015-01-01

    Chaining or cascading of different actions and responses is necessary to accomplish a goal. Yet, little is known about the functional neuroanatomical-electrophysiological mechanisms mediating these processes. Computational models suggest that medium spiny neurons (MSNs) play an important role in action cascading, but this assumption has hardly been tested relating neuroanatomical and electrophysiological parameters in a human model of circumscribed MSN dysfunction. As a possible human model of circumscribed MSN dysfunction, we investigate benign hereditary chorea in a case-control study applying bootstrap statistics. To investigate these mechanisms, we used a stop-change paradigm, where we apply mathematical constraints to describe the degree of how task goals are activated with more or less overlap during action cascading. We record event-related potentials and analyze neural synchronization processes. The results show that MSN dysfunctions lead to deficits in action cascading processes only when two response options seek simultaneous access to response selection resources. Attentional selection processes are not affected, but processes reflecting the transition between stimulus evaluation and responding are affected. The results underline computational models of MSN functioning and show that dysfunction in these networks leads to a more parallel and hence inefficient response selection. PMID:24135770

  1. Differences in number and distribution of striatal calbindin medium spiny neurons between a vocal-learner (Melopsittacus undulatus) and a non-vocal learner bird (Colinus virginianus)

    PubMed Central

    Garcia-Calero, Elena; Bahamonde, Olga; Martinez, Salvador

    2013-01-01

    Striatal projecting neurons, known as medium spiny neurons (MSNs), segregate into two compartments called matrix and striosome in the mammalian striatum. The matrix domain is characterized by the presence of calbindin immunopositive (CB+) MSNs, not observed in the striosome subdivision. The existence of a similar CB+ MSN population has recently been described in two striatal structures in male zebra finch (a vocal learner bird): the striatal capsule and the Area X, a nucleus implicated in song learning. Female zebra finches show a similar pattern of CB+ MSNs than males in the developing striatum but loose these cells in juveniles and adult stages. In the present work we analyzed the existence and allocation of CB+ MSNs in the striatal domain of the vocal learner bird budgerigar (representative of psittaciformes order) and the non-vocal learner bird quail (representative of galliformes order). We studied the co-localization of CB protein with FoxP1, a transcription factor expressed in vertebrate striatal MSNs. We observed CB+ MSNs in the medial striatal domain of adult male and female budgerigars, although this cell type was missing in the potentially homologous nucleus for Area X in budgerigar. In quail, we observed CB+ cells in the striatal domain at developmental and adult stages but they did not co-localize with the MSN marker FoxP1. We also described the existence of the CB+ striatal capsule in budgerigar and quail and compared these results with the CB+ striatal capsule observed in juvenile zebra finches. Together, these results point out important differences in CB+ MSN distribution between two representative species of vocal learner and non-vocal learner avian orders (respectively the budgerigar and the quail), but also between close vocal learner bird families. PMID:24391552

  2. 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

  3. 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

  4. A Golgi study on the neuronal organization of the neostriatum in the mouse.

    PubMed

    Iwahori, N; Kiyota, E

    1987-08-01

    The neuronal organization of the neostriatum in mice was studied, using the rapid Golgi method. Based on the size of the somata, the neostriatal neurons were divided into groups of large, medium-sized and small cells, and the neurons of each group were further divided into 2-5 types, according to the shape of the somata and dendritic morphology. Three types of large neurons were recognized. Large type I neurons were triangular, piriform or fusiform cells with a few thick dendrites, whereas large type II and type III neurons were round or polygonal cells with numerous slender dendrites. The dendrites of the large type II neurons were far longer than those of large type III. Medium-sized neurons were grouped into 5 types. Medium type I neurons were round with spiny dendrites and were found mainly in the caudal portion of the neostriatum. Medium type II neurons had numerous thin dendrites and were predominant in the rostral portion of the neostriatum. Some medium type II neurons were arranged in cell chains extending perpendicular to Wilson's pencils. The cell bodies of medium type III neurons were triangular, and generated long spiny dendrites. Medium type IV neurons were polygonal, and dendrites with numerous short branchlets were evidenced. Medium type V neurons had poorly branched and sparsely spinous dendrites. The small neurons were of two types: small type I had piriform cell bodies, which gave rise to very thin dendrites, while small type II had dendrites with irregular contours and filiform appendages. Of these, the large type I and type II, the medium type I-V, and the small type I neurons seemed to be the projection neurons, whereas the large type III and small type II neurons were merely internuncials. Thus, the neostriatum in the mouse was shown to be composed of a wide variety of projection neurons and only two types of interneurons. PMID:2446216

  5. Segregation and crosstalk of D1 receptor-mediated activation of ERK in striatal medium spiny neurons upon acute administration of psychostimulants.

    PubMed

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

    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/Ca(2+)/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/Ca(2+)/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

  6. 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

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

    PubMed

    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

  8. 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…

  9. 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)

  10. 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…

  11. Using Bitmaps for Medium Sized Information Retrieval Systems.

    ERIC Educational Resources Information Center

    Bookstein, A.; Klein, S. T.

    1990-01-01

    Describes the theoretical framework of a retrieval system that uses data structures called bitmaps to improve search algorithms for medium-sized systems. Information retrieval systems that contain the full text of the documents are discussed, and the use of inverted files such as concordances for small texts is explained. (24 references) (LRW)

  12. Enantioselective Synthesis of Indole-Annulated Medium-Sized Rings.

    PubMed

    Huang, Lin; Dai, Li-Xin; You, Shu-Li

    2016-05-11

    Asymmetric synthesis of indole-annulated medium-sized-ring compounds is developed through an iridium-catalyzed allylic dearomatization/retro-Mannich/hydrolysis cascade reaction. The reaction features mild conditions and a broad substrate scope. Under the optimal conditions, various seven-, eight-, or nine-membered-ring compounds can be afforded in good to excellent yields and excellent enantioselectivity. The proposed mechanism is supported by capturing the dearomatized intermediate through in situ reduction. PMID:27093370

  13. Micadur: Compact insulation system for medium-sized turbo generators

    NASA Astrophysics Data System (ADS)

    Aare, V.; Schuler, R. H.

    1981-12-01

    A high voltage, Class F, vacuum pressure impregnated insulation system for wound stator cores of the medium size turbogenerators is described. With this total impregnation technique the insulation process has been revolutionized. The excellent characteristics of this synthetic resin insulation system have made it possible to redesign the end winding support system for decisive improvement in reliability. This has been confirmed by operating experience in recent years. Test procedures were modified to suit the new insulation process and new repair procedures have been developed.

  14. 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.

  15. Differential effects of cocaine on histone posttranslational modifications in identified populations of striatal neurons.

    PubMed

    Jordi, Emmanuelle; Heiman, Myriam; Marion-Poll, Lucile; Guermonprez, Pierre; Cheng, Shuk Kei; Nairn, Angus C; Greengard, Paul; Girault, Jean-Antoine

    2013-06-01

    Drugs of abuse, such as cocaine, induce changes in gene expression and epigenetic marks including alterations in histone posttranslational modifications in striatal neurons. These changes are thought to participate in physiological memory mechanisms and to be critical for long-term behavioral alterations. However, the striatum is composed of multiple cell types, including two distinct populations of medium-sized spiny neurons, and little is known concerning the cell-type specificity of epigenetic modifications. To address this question we used bacterial artificial chromosome transgenic mice, which express EGFP fused to the N-terminus of the large subunit ribosomal protein L10a driven by the D1 or D2 dopamine receptor (D1R, D2R) promoter, respectively. Fluorescence in nucleoli was used to sort nuclei from D1R- or D2R-expressing neurons and to quantify by flow cytometry the cocaine-induced changes in histone acetylation and methylation specifically in these two types of nuclei. The two populations of medium-sized spiny neurons displayed different patterns of histone modifications 15 min or 24 h after a single injection of cocaine or 24 h after seven daily injections. In particular, acetylation of histone 3 on Lys 14 and of histone 4 on Lys 5 and 12, and methylation of histone 3 on Lys 9 exhibited distinct and persistent changes in the two cell types. Our data provide insights into the differential epigenetic responses to cocaine in D1R- and D2R-positive neurons and their potential regulation, which may participate in the persistent effects of cocaine in these neurons. The method described should have general utility for studying nuclear modifications in different types of neuronal or nonneuronal cell types. PMID:23690581

  16. Electrophysiological and Morphological Characteristics and Synaptic Connectivity of Tyrosine Hydroxylase-Expressing Neurons in Adult Mouse Striatum

    PubMed Central

    Ibáñez-Sandoval, Osvaldo; Tecuapetla, Fatuel; Unal, Bengi; Shah, Fulva; Koós, Tibor; Tepper, James M.

    2015-01-01

    Whole-cell recordings were obtained from tyrosine hydroxylase-expressing (TH+) neurons in striatal slices from bacterial artificial chromosome transgenic mice that synthesize enhanced green fluorescent protein (EGFP) selectively in neurons expressing TH transcriptional regulatory sequences. Stereological cell counting indicated that there were ~2700 EGFP–TH+ neurons/striatum. Whole-cell recordings in striatal slices demonstrated that EGFP–TH+ neurons comprise four electrophysiologically distinct neuron types whose electrophysiological properties have not been reported previously in striatum. EGFP–TH+ neurons were identified in retrograde tracing studies as interneurons. Recordings from synaptically connected pairs of EGFP–TH+ interneurons and spiny neurons showed that the interneurons elicited GABAergic IPSPs/IPSCs in spiny neurons powerful enough to significantly delay evoked spiking. EGFP–TH+ interneurons responded to local or cortical stimulation with glutamatergic EPSPs. Local stimulation also elicited GABAA IPSPs, at least some of which arose from identified spiny neurons. Single-cell reverse transcription-PCR showed expression of VMAT1 in EGFP–TH+ interneurons, consistent with previous suggestions that these interneurons may be dopaminergic as well as GABAergic. All four classes of interneurons were medium sized with modestly branching, varicose dendrites, and dense, highly varicose axon collateral fields. These data show for the first time that there exists in the normal rodent striatum a substantial population of TH+/GABAergic interneurons comprising four electrophysiologically distinct subtypes whose electrophysiological properties differ significantly from those of previously described striatal GABAergic interneurons. These interneurons are likely to play an important role in striatal function through fast GABAergic synaptic transmission in addition to, and independent of, their potential role in compensation for dopamine loss in experimental

  17. BTX measurements in a medium-sized European city

    NASA Astrophysics Data System (ADS)

    Pilidis, Georgios A.; Karakitsios, Spyros P.; Kassomenos, Pavlos A.

    The BTX levels are significantly high compared to the EU directive for benzene in European cities with population around or higher one million. Since there are hundreds of towns in Europe with smaller population, it is important to know the levels of aromatics in these areas. This work presents the results of a benzene, toluene and xylene (BTX) measurement campaign that took place in Ioannina, a medium-sized Greek city. As a result of traffic situation and the local meteorological conditions, pollution levels in Ioannina are unusually high, at least for a city of that size. BTX levels were measured using passive samplers placed at several points around the city, as well as across a selected street canyon using both passive and active samplers, combined with simultaneous measurements of traffic flow and wind speed. The measurement procedure was repeated in an exact manner for all four seasons and the results suggest that benzene levels, at all sampling points, exceed the limit set by EU Directive 2000/69. Benzene levels appear correlated to traffic density, while benzene/toluene/xylene ratios present a seasonal variation linked to meteorological conditions.

  18. 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.

  19. Overview of the EUROfusion Medium Size Tokamak program

    NASA Astrophysics Data System (ADS)

    Martin, Piero; Beurskens, Marc; Coda, Stefano; Eich, Thomas; Meyer, Hendrik; the EUROfusion MST1 Team

    2015-11-01

    As a result of the new organization of the European fusion programme, now under the umbrella of the EUROfusion Consortium, the MST (Medium Size Tokamaks) task force is in charge of executing 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 2014 campaign-where only ASDEX upgrade was operating-and the preliminary achievements of the recently started 2015/16 campaign, where also TCV will contribute. The main subjects of the experimental campaigns are (i) the development of scenarios relevant for the ITER Q=10 goal, in an all metal wall device (ii) the understanding of ELM mitigation/suppression with pellets and resonant magnetic perturbations, and in particular the effect of density versus collisionality, (iii) the understanding and optimization of methods for disruption mitigation or avoidance and runaway electrons control and (iv) the exploration of ITER and DEMO relevant scenarios with high normalized separatrix power flux, Psep / R , (Psep is the power through the separatrix, R the major radius) and tolerable target heat loads. The overview of the future programs in MST will be given. http://www.euro-fusionscipub.org/mst1

  20. Accurate thermochemistry for medium-sized and large molecules

    SciTech Connect

    Raghavachari, K.; Stefanov, B.B.; Curtiss, L.A.

    1997-12-31

    Accurate techniques such as Gaussian-2 (G2) theory have been proposed in recent years to evaluate the thermochemistry of small molecules from first-principles. However, as the molecules get larger, the errors in G2 theory and similar approaches tend to accumulate. For example, the computed heats of formation of benzene and naphthalene with G2 and G2(MP2) theories, respectively, have errors of 3.9 and 7.2 kcal/mol. In this work, we explore strategies for computing accurate heats of formation for medium-sized and large molecules. In our first scheme, G2 theory is combined with isodesmic bond separation reaction energies to yield accurate thermochemistry for larger molecules. For a test set of 40 molecules composed of H, C, O, and N, our method yields enthalpies of formation, {Delta}H{sub f}{sup 0}(298 K), with a mean absolute deviation from experiment of only 0.5 kcal/mol. This is an improvement of a factor of three over the deviation of 1.5 kcal/mol seen in standard G2 theory.

  1. 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.

  2. Theory of flotation of small and medium-size particles

    NASA Astrophysics Data System (ADS)

    Derjaguin, B. V.; Dukhin, S. S.

    1993-08-01

    The paper describes a theory of flotation of small and medium-size particles less than 50μ in radius) when their precipitation on a bubble surface depends more on surface forces than on inertia forces, and deformation of the bubble due to collisions with the particles may be neglected. The approach of the mineral particle to the bubble surface is regarded as taking place in three stages corresponding to movement of the particles through zones 1, 2 and 3. Zone 3 is a liquid wetting layer of such thickness that a positive or negative disjoining pressure arises in this intervening layer between the particle and the bubble. By zone 2 is meant the diffusional boundary layer of the bubble. In zone 1, which comprises the entire liquid outside zone 2, there are no surface forces. Precipitation of the particles is calculated by considering the forces acting in zones 1, 2 and 3. The particles move through zone 1 under the action of gravity and inertia. Analysis of the movement of the particles under the action of these forces gives the critical particle size, below which contact with the bubble surface is impossible, if the surface forces acting in zones 2 and 3 be neglected. The forces acting in zone 2 are ‘diffusio-phoretic’ forces due to the concentration gradient in the diffusional boundary layer. The concentration and electric field intensity distribution in zone 2 is calculated, taking into account ion diffusion to the deformed bubble surface. An examination is made of the ‘equilibrium’ surface forces acting in zone 3 independent of whether the bubble is at rest or in motion. These forces, which determine the behaviour of the thin wetting intervening layer between the bubble and the mineral particle and the height of the force barrier against its rupture, may be represented as results of the disjoining pressure forces acting on various parts of the film. The main components of the disjoining pressure are van der Waals forces, forces of an iono

  3. 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.

  4. Management Education for Small and Medium-Sized Enterprises in the European Communities.

    ERIC Educational Resources Information Center

    Holzer, Rainer

    This report summarizes the activities of various bodies providing training impetus for small and medium-sized enterprises (SMEs) in Europe on the three levels of (1) basic management education for potential small and medium-sized business owners and/or managers; (2) programs for small firm start-ups; and (3) activities to improve the management of…

  5. 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…

  6. The development of internet based ship design support system for small and medium sized shipyards

    NASA Astrophysics Data System (ADS)

    Shin, Sung-Chul; Lee, Soon-Sup; Kang, Dong-Hoon; Lee, Kyung-Ho

    2012-03-01

    In this paper, a prototype of ship basic planning system is implemented for the small and medium sized shipyards based on the internet technology and concurrent engineering concept. The system is designed from the user requirements. Consequently, standardized development environment and tools are selected. These tools are used for the system development to define and evaluate core application technologies. The system will contribute to increasing competitiveness of small and medium sized shipyards in the 21st century industrial en-vironment.

  7. [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). PMID:2410488

  8. Activin A directs striatal projection neuron differentiation of human pluripotent stem cells

    PubMed Central

    Arber, Charles; Precious, Sophie V.; Cambray, Serafí; Risner-Janiczek, Jessica R.; Kelly, Claire; Noakes, Zoe; Fjodorova, Marija; Heuer, Andreas; Ungless, Mark A.; Rodríguez, Tristan A.; Rosser, Anne E.; Dunnett, Stephen B.; Li, Meng

    2015-01-01

    The efficient generation of striatal neurons from human embryonic stem cells (hESCs) and induced pluripotent stem cells (hiPSCs) is fundamental for realising their promise in disease modelling, pharmaceutical drug screening and cell therapy for Huntington's disease. GABAergic medium-sized spiny neurons (MSNs) are the principal projection neurons of the striatum and specifically degenerate in the early phase of Huntington's disease. Here we report that activin A induces lateral ganglionic eminence (LGE) characteristics in nascent neural progenitors derived from hESCs and hiPSCs in a sonic hedgehog-independent manner. Correct specification of striatal phenotype was further demonstrated by the induction of the striatal transcription factors CTIP2, GSX2 and FOXP2. Crucially, these human LGE progenitors readily differentiate into postmitotic neurons expressing the striatal projection neuron signature marker DARPP32, both in culture and following transplantation in the adult striatum in a rat model of Huntington's disease. Activin-induced neurons also exhibit appropriate striatal-like electrophysiology in vitro. Together, our findings demonstrate a novel route for efficient differentiation of GABAergic striatal MSNs from human pluripotent stem cells. PMID:25804741

  9. 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...

  10. 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...

  11. 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...

  12. 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...

  13. 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...

  14. 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...

  15. 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...

  16. 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...

  17. 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...

  18. 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...

  19. 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...

  20. 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...

  1. 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...

  2. Diseases of spiny lobsters: a review.

    PubMed

    Shields, J D

    2011-01-01

    Spiny lobsters have few reported pathogens, parasites and symbionts. However, they do have a diverse fauna comprised of a pathogenic virus, several bacteria, protozoans, helminths and even symbiotic crustaceans. A few idiopathic syndromes have also been reported, but these appear correlated with lobsters held in poor conditions. Fungal and bacterial pathogens present significant threats for rearing spiny lobsters in aquaculture settings, but only one pathogen, Panulirus argus virus 1, is thought to have damaged a fishery for a spiny lobster. No doubt others will emerge as lobsters are brought into aquaculture setting and as fishing pressure intensifies with stocks become more susceptible to anthropogenic stressors. PMID:21215357

  3. Continuing Education for Managers from Small and Medium Sized German Companies.

    ERIC Educational Resources Information Center

    Fub, Jorg

    1995-01-01

    An international trade school in southern Germany, which is a highly export-oriented environment, has established a vocational and professional continuing education program for personnel of small- and medium-size companies. Offerings include a graduate course in international marketing, seminars for export companies, distance education in…

  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. 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…

  6. 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.

  7. 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…

  8. An Examination of Library World Wide Web Sites at Medium-Sized Universities.

    ERIC Educational Resources Information Center

    Tolppanen, Bradley P.; Miller, Joan; Wooden, Martha H.

    2000-01-01

    Presents the results of a study of Web sites for 133 academic libraries serving medium-sized universities. Suggests that navigational and design aspects need improvement; information should not be included unless it will be accessed and used; and greater use should be made of online tutorials and virtual tours to supplement regular bibliographic…

  9. 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…

  10. 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…

  11. 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…

  12. 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…

  13. 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…

  14. 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.

  15. Services Supporting Knowledge Maturing in Small and Medium-Sized Enterprises

    NASA Astrophysics Data System (ADS)

    Maier, Ronald

    The hype around Web 2.0 has again sparked tremendous interest in IT-supported knowledge management and technology-enhanced learning in organizations. Although there has been abundant evidence of how to benefit from Web 2.0 technologies, information on how to go about deploying these in small and medium-sized enterprises in a coordinated manner are scarce. Based on the findings of an empirical study and an ethnographically informed study on knowledge maturing, this paper suggests a set of knowledge services to support a series of knowledge actions chained with the help of the knowledge maturing model. This set of services can be used by small and medium-sized enterprises for analyzing IT tools and systems which currently support their employees’ knowledge maturing activities, to foster knowledge cooperation with customers, suppliers and partners in their business environment and to find gaps which can be filled particularly by consuming services over the Web.

  16. 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.

  17. Financial and Tax Management in Small and Medium Sized Industrial Enterprises

    NASA Astrophysics Data System (ADS)

    Bestvinová, Viera; Homokyová, Mária; Horváthová, Martina

    2012-12-01

    Target of this paper was to evaluate the importance of small and medium sized enterprises (SMEs) in Slovakia and to determine the application of financial and tax management in this type of enterprises. The results of our findings confirm that SMEs have an important role in Slovakia, and also that especially small businesses have little or no experience with the application of financial and tax management. Therefore the paper contains recommendations for financial and tax management of SMEs.

  18. Assessing the effectiveness of safeguards at a medium-sized spent-fuel reprocessing facility

    SciTech Connect

    Higinbotham, W.; Fishbone, L.G.; Suda, S.

    1983-01-01

    In order to evaluate carefully and systematically the effectiveness of safeguards at nuclear-fuel-cycle facilities, the International Atomic Energy Agency has adopted a safeguards effectiveness assessment methodology. The methodology has been applied to a well-characterized, medium-sized, spent-fuel reprocessing plant to understand how explicit safeguards inspection procedures would serve to expose conceivable nuclear materials diversion schemes, should such diversion occur.

  19. 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

  20. 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. PMID:27154382

  1. 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.

  2. Open adrenalectomy for medium sized adrenocortical tumour: How I do it?

    PubMed Central

    Sameh, Wael M.; Kotb, Ahmed Fouad

    2015-01-01

    Introduction: The aim of our work was to report our experience in managing cases with medium-sized adrenocortical carcinoma by the high retroperitoneal extra pleural approach. Methods: During the past 2 years, 10 patients with suspected adrenocortical carcinoma were managed by our technique: the high supra 10th rib, retroperitoneal extra pleural approach. We included cases with 5 to 10 cm adrenal masses, suspected as adrenocortical carcinoma. Results: The mean patient age was 38 years (range: 26–44), the median tumour volume was 7 cm (range: 5–8). Of the 10 patients, 7 were female. Of the patients, 6 had right- and 4 had left-sided tumours. Intraoperatively, all cases had proper surgical removal, with no apparent residual tumour tissue. No single patient required a chest tube or developed respiratory problems. There were no major vascular injuries during surgery. We did not compare our findings to the standard lateral or subcostal approaches, as in our institution we adopt this high lateral approach for medium-sized tumours, while managing larger tumours with transperitoneal subcostal approach and smaller tumours laparoscopically. Conclusion: The high supra 10th lateral retroperitoneal, extra pleural approach is a safe, doable technique, allowing easy access to medium-sized suprarenal tumours and its vasculature, for cases suspected to be adrenocortical carcinoma. PMID:26029297

  3. Identification of medium-sized genomic deletions with low coverage, mate-paired restricted tags

    PubMed Central

    2013-01-01

    Background Genomic deletions are known to be widespread in many species. Variant sequencing-based approaches for identifying deletions have been developed, but their powers to detect those deletions that affect medium-sized regions are limited when the sequencing coverage is low. Results We present a cost-effective method for identifying medium-sized deletions in genomic regions with low genomic coverage. Two mate-paired libraries were separately constructed from human cancerous tissue to generate paired short reads (ditags) from restriction fragments digested with a 4-base restriction enzyme. A total of 3 Gb of paired reads (1.0× genome size) was collected, and 175 deletions were inferred by identifying the ditags with disorder alignments to the reference genome sequence. Sanger sequencing results confirmed an overall detection accuracy of 95%. Good reproducibility was verified by the deletions that were detected by both libraries. Conclusions We provide an approach to accurately identify medium-sized deletions in large genomes with low sequence coverage. It can be applied in studies of comparative genomics and in the identification of germline and somatic variants. PMID:23347462

  4. 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...

  5. 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...

  6. 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...

  7. 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...

  8. 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...

  9. 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...

  10. 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...

  11. 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...

  12. 75 FR 5804 - Small and Medium-Sized Enterprises: U.S. and EU Export Activities, and Barriers and Opportunities...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-02-04

    ... published in the Federal Registers of October 28, 2009 (74 FR 55581); December 1, 2009 (74 FR 62812); and... COMMISSION Small and Medium-Sized Enterprises: U.S. and EU Export Activities, and Barriers and Opportunities Experienced by U.S. Firms and Small and Medium-Sized Enterprises: Characteristics and Performance...

  13. 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... fabricated rubber plants subcategory. The following provisions of this subpart are applicable to...

  14. 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...

  15. 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.

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

    SciTech Connect

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

    2010-06-22

    In this study a feasibility 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 deg. 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 criticality was obtained for this reactor.

  17. Acitretin-induced spiny follicular hyperkeratosis.

    PubMed

    Yanik, Mehmet Emin; Erfan, Gamze; Albayrak, Hulya; Tasolar, Kaan; Albayrak, Sule; Gelincik, Ibrahim; Kulac, Mustafa

    2016-06-01

    Spiny follicular hyperkeratosis (SFH) is follicular flesh-colored hyperkeratotic spicules that are linked to different situations including drug reactions. Previously suspected drugs are BRAF inhibitors and cyclosporine. We described a 51-year-old psoriasis patient with SFH who had been using acitretin. PMID:26340416

  18. 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. PMID:11276261

  19. 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

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

    PubMed Central

    SHEN, YAN; SHEN, MINGGAO; XU, ZHONG; BAI, YING

    2014-01-01

    Summary 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. PMID:26052179

  1. 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 Spiny Dogfish Monitoring Committee shall recommend to the Joint Spiny Dogfish Committee, an ACL for...

  2. 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 Spiny Dogfish Monitoring Committee shall recommend to the Joint Spiny Dogfish Committee, an ACL for...

  3. Increase of chronic low back pain prevalence in a medium-sized city of southern Brazil

    PubMed Central

    2013-01-01

    Background Chronic low back pain (CLBP) is a highly disabling morbidity with high social, economic and individual effects. Demographic, occupational and behavioral changes that took place in Brazil over the last decade are related with an increasing burden of chronic conditions. Despite these changes, comparison studies on CLBP prevalence and associated factors, over time are scarce in the literature in general, and unknown in Brazil. The present study compared the CLBP prevalence in a medium sized city in Brazil between the years 2002 and 2010 and examined factors associated with prevalence in 2010. Methods Two cross-sectional studies with similar methodology were conducted in a medium-sized city in southern Brazil, in 2002 and 2010. 3182 individuals were interviewed in the first study and 2732 in the second one, all adults aged twenty years or more. Those who reported pain for seven weeks or more in the last three months in the lumbar region where considered cases of CLBP. Results The CLBP prevalence increased from 4.2% to 9.6% in 8 years. In most of the studied subgroups the CLBP prevalence has at least doubled and the increase was even larger among younger individuals with more years of education and higher economic status. Conclusions Increase in CLBP prevalence is worrisome because it is a condition responsible for substantial social impact, besides being an important source of demand for health services. PMID:23634830

  4. Detection of Clostridium difficile in small and medium-sized wild Mammals in Southern Ontario, Canada.

    PubMed

    Jardine, Claire M; Reid-Smith, Richard J; Rousseau, Joyce; Weese, J Scott

    2013-04-01

    We sampled 325 small and medium-sized wild mammals in Ontario, Canada in 2007 and 2010 to determine the prevalence and characteristics of Clostridium difficile in wild mammals living in proximity to captive wildlife and livestock. Clostridium difficile was isolated from five of 109 animals (4.6%) on four of 25 farms (16%), but was not isolated from any of the 216 samples from raccoons (Procyon lotor) living on the grounds of the Toronto Zoo. The positive animals included two raccoons from one beef farm, one raccoon from a different beef farm, one raccoon from a swine farm, and a shrew (Blarina brevicauda) from a dairy farm. None had evidence of gastrointestinal disease. Three of the five isolates were toxinotype variants (II, IV, and XIII) that are rarely identified in humans and domestic animals. The other two were toxinotype 0, a common toxinotype in humans and animals; however, all five isolates were of different ribotypes. None of the recovered ribotypes were recognized as ribotypes present in the authors' reference library of over 3,000 human and domestic animal C. difficile isolates. Neither the public health nor the animal health relevance of these findings is clear. It is not known whether C. difficile is a pathogen of small and medium-sized wild mammals, although the susceptibility of various laboratory species suggests it could cause disease. PMID:23568920

  5. Performance of a Medium-Size Area nGEM Detector for Neutron Beam Diagnostics

    NASA Astrophysics Data System (ADS)

    Croci, G.; Cazzaniga, C.; Albani, G.; Muraro, A.; Claps, G.; Cavenago, M.; Grosso, G.; Murtas, F.; Pasqualotto, R.; Cippo, E. Perelli; Rebai, M.; Tardocchi, M.; Gorini, G.

    Fast neutron detectors with a sub-centimetric space resolution are required in order to qualify neutron beams in applications related to magnetically-controlled nuclear fusion plasmas and to spallation sources. Based on the results obtained with small area prototypes, the first medium-size (20 x 35.2 cm2 active area) nGEM detector has been realized for both the CNESM diagnostic system of the SPIDER NBI prototype for ITER and as a beam monitor for fast neutrons beam lines at spallation sources, too. The nGEM is a Triple GEM gaseous detector equipped with polyethylene layers used to convert fast neutrons into recoil protons through the elastic scattering process. This paper describes the performance of the medium-size nGEM detector tested at the VESUVIO beam line of the ISIS spallation source. Being this detector the actual largest area fast neutron detector based on the GEM technology, particular attention was paid in the study of detector response in different points over the active area. Measurements of GEM counting rate (both as a function of VGEM and of time) and of the capability of the detector to reconstruct the beam in different positions are presented. This detector serves as a basis for the realization of an even larger area detector that will be used in the MITICA NBI prototype for ITER that represents the evolution of SPIDER.

  6. [Application of health questionnaires for health management in small- and medium-sized enterprises].

    PubMed

    Kishida, K; Saito, M; Hasegawa, T; Aoki, S; Suzuki, S

    1986-01-01

    Two kinds of health questionnaires, the Todai Health Index (THI) and Cumulative Fatigue Index (CFI), were applied as a screening device for health management of workers belonging to small-medium sized enterprises. A total of 495 workers composed of 452 male workers of a glass-bottle manufacturing factory and 43 male workers of a soft-drink bottling factory were the subjects of the present study. It was found that the two kinds of health questionnaires were different from each other and have their own characteristics. Twelve scales of THI were grouped into two, the first consisting of ten scales (SUSY, RESP, EYSK, MOUT, DIGE, IMPU, MENT, DEPR, NERV, and LIFE) and the second consisting of two scales (AGGR and LISC). Nine categories of CFI were grouped into one by using principal factor analysis. It was confirmed that the twelve scale scores of THI obtained at small-medium sized factories differed from those scale scores of a reference group investigated at a large-sized enterprise. It is on the basis of the scales of aggressiveness and lies and also of the scale of mental unstability which characterizes workers, locality, job (clerical or field work), and size of industry (large or small sized) that the difference could be evaluated. Urban life characterized by a life style of staying up late at night and waking up late in the morning has been reflected on the scale of life irregularity. Irregularity of life induced by transformation of working schedule, such as two or three shifts of work and overtime, was also reflected on this scale. Two scales of THI test, i.e., many subjective symptoms and digestive organ complaints, seemed to be the representative scales indicating a close relation between work load and health level. The discriminant score for diagnosis of psychosomatic diseases is considered to be one of the most useful assessments of the individual's health condition. As mentioned above, THI is recommended as a convenient assessment method for health

  7. 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.

  8. 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.

  9. 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.

  10. 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

    2016-05-01

    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. PMID:27155640

  11. 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.

  12. Benchmarking Density Functionals on Structural Parameters of Small-/Medium-Sized Organic Molecules.

    PubMed

    Brémond, Éric; Savarese, Marika; Su, Neil Qiang; Pérez-Jiménez, Ángel José; Xu, Xin; Sancho-García, Juan Carlos; Adamo, Carlo

    2016-02-01

    In this Letter we report the error analysis of 59 exchange-correlation functionals in evaluating the structural parameters of small- and medium-sized organic molecules. From this analysis, recently developed double hybrids, such as xDH-PBE0, emerge as the most reliable methods, while global hybrids confirm their robustness in reproducing molecular structures. Notably the M06-L density functional is the only semilocal method reaching an accuracy comparable to hybrids'. A comparison with errors obtained on energetic databases (including thermochemistry, reaction barriers, and interaction energies) indicate that most of the functionals have a coherent behavior, showing low (or high) deviations on both energy and structure data sets. Only a few of them are more prone toward one of these two properties. PMID:26730741

  13. 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.

  14. 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. PMID:24215708

  15. 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

  16. Signaling in striatal neurons: the phosphoproteins of reward, addiction, and dyskinesia.

    PubMed

    Girault, Jean-Antoine

    2012-01-01

    The striatum is a deep region of the forebrain involved in action selection, control of movement, and motivation. It receives a convergent excitatory glutamate input from the cerebral cortex and the thalamus, controlled by dopamine (DA) released in response to unexpected rewards and other salient stimuli. Striatal function and its dysfunction in drug addiction or Parkinson's disease depend on the interplay between these neurotransmitters. Signaling cascades in striatal medium-sized spiny neurons (MSNs) involve multiple kinases, phosphatases, and phosphoproteins, some of which are highly enriched in these neurons. They control the properties of ion channels and the plasticity of MSNs, in part through their effects on gene transcription. This chapter summarizes signaling in MSNs and focuses on the regulation of multiple protein phosphatases through DA and glutamate receptors and the role of ERK. It is hypothesized that these pathways are particularly adapted to the specific computing properties of MSNs and the function of the basal ganglia circuits in which they participate. PMID:22340713

  17. 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 Section 648.232 Wildlife and Fisheries FISHERY CONSERVATION AND MANAGEMENT, NATIONAL OCEANIC AND ATMOSPHERIC ADMINISTRATION, DEPARTMENT OF COMMERCE FISHERIES OF THE NORTHEASTERN UNITED STATES Management Measures for the Spiny Dogfish Fishery §...

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

    SciTech Connect

    Laner, David Rechberger, Helmut

    2009-02-15

    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.

  19. Volatile organic compounds in small- and medium-sized commercial buildings in California.

    PubMed

    Wu, Xiangmei May; Apte, Michael G; Maddalena, Randy; Bennett, Deborah H

    2011-10-15

    While small- and medium-sized commercial buildings (SMCBs) make up 96% of the commercial buildings in the U.S., serving a large variety of uses, little information is available on indoor air quality (IAQ) in SMCBs. This study investigated 37 SMCBs distributed across different sizes, ages, uses, and regions of California. We report indoor concentrations and whole building emission rates of a suite of 30 VOCs and aldehydes in these buildings. There was a considerable range in the concentrations for each of the contaminants, especially for formaldehyde, acetaldehyde, decamethylcyclopentasiloxane, d-limonene, 2-butoxyethanol, toluene, 2,2,4-trimethylpentanediol diisobutyrate, and diethylphthalate. The cause of higher concentrations in some building categories generally corresponded to expected sources, for example, chloroform was higher in restaurants and grocery stores, and formaldehyde was higher in retail stores and offices. Factor analysis suggests sources in SMCBs include automobile/traffic, cleaning products, occupant sources, wood products/coating, and plasticizers. The comparison to health guidelines showed that formaldehyde concentrations were above the chronic RELs required by the OEHHA (9 μg/m³) in 86% of the buildings. Data collected in this study begins to fill the knowledge gap for IAQ in SMCBs and helps us understand the indoor sources of VOCs to further improve indoor air quality in SMCBs. PMID:21888354

  20. 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.

  1. 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. PMID:21809475

  2. 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.

  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. PMID:21372441

  4. Medium-size power generation market now focus of Rolls-Royce

    SciTech Connect

    Mullins, P.

    1996-12-01

    John Rose, Rolls-Royce chief executive, explained that the focus in power generation would now be upon small- and medium-sized power applications up to 150MW using its ranges of aeroderivative gas turbines, small steam turbines and diesel engines. The company already has an established position in this area and expects to become more competitive as aeroderivative gas turbines like the marine WR21 and industrial Trent reach the market. A measure of Rolls-Royce`s broad capability in medium power generation can be seen in the company`s decision to build its own cogen power station to provide heat and power to its major aerospace manufacturing facilities at Derby in the U.K. Work has already started on preparing land adjoining the site and the 60 MW power station is scheduled to go on line in January 1998. The US$60 million project is being carried out by Derby Cogeneration, a joint venture between Rolls-Royce Power Ventures and National Power Cogen, a subsidiary of the U.K.`s largest electrical power generator. 5 figs.

  5. Continuous improvement of the quality reporting system of a medium-size company

    NASA Astrophysics Data System (ADS)

    Hawkins, Anthony; Onuh, Spencer

    2001-10-01

    Many companies are faced with quality improvement issues on a daily basis but their response to this problem varies. This paper discusses the improvement in the defect reporting system at a medium sized manufacturing company following the appointment of an experienced, motivated, design engineer to be dedicated to that task. It sets out the situation that the engineer inherited and details the changes that were incorporated; it assesses which were successful and which failed. Following a survey of current literature, it was seen that there is little written specifically on the subject of audited defect reporting. It is felt that this study goes some way to filling that void. A successful survey of engineering companies in Southern Hampshire reinforces the principle findings, that the emphasising of the Check part of Demming's Plan-Do-Check-Act cycle is a novel approach to the Quality Improvement Process, and that it has reduced the cost of rework by an audited 80% in a period of two years.

  6. Ticks (Acari: Ixodidae) collected from small and medium-sized Kansas mammals.

    PubMed

    Brillhart, D B; Fox, L B; Upton, S J

    1994-05-01

    Seven species of hard-bodied ticks were collected from 20 species of small and medium-sized mammals in Kansas; Amblyomma americanum L., Dermacentor variabilis (Say), Haemaphysalis leporispalustris (Packard), Ixodes cookei Packard, I. kingi Bishopp, I. sculptus Neumann, and I. texanus Banks. Dermacentor variabilis was found statewide, A. americanum only in the eastern one-third of the state, and the Ixodes spp. and H. leporispalustris were widely scattered. The most common tick found was D. variabilis, both by itself and in association with other ticks. Mammals that ticks were collected from included Canis latrans Say, Cynomys ludovicianus ludovicianus (Ord), Didelphis virginianus Kerr, Geomys bursarius (Shaw), Lynx rufus (Schreber), Marmota monax bunkeri Black, Mephitis mephitis (Schreber), Microtus ochrogaster (Wagner), Mus musculus L., Peromyscus leucopus (Rafinesque), P. maniculatus (Wagner), Procyon lotor hirtus Nelson and Goldman, Reithrodontomys megalotis (Baird), Sciurus niger rufiventer Geoffroy, Sigmodon hispidus texianus (Audubon and Bachman), Sylvilagus floridanus (J. A. Allen), Taxidea taxus taxus (Schreber), and Vulpes velox velox (Say). PMID:8057327

  7. Ixodes dammini (Acari: Ixodidae) infestation on medium-sized mammals and blue jays in northwestern Illinois.

    PubMed

    Mannelli, A; Kitron, U; Jones, C J; Slajchert, T L

    1993-09-01

    High prevalence of infestation of five species of medium-sized mammals and blue jays, Cyanocitta cristata (L.), by immature Ixodes dammini Spielman, Clifford, Piesman and Corwin was found in Castle Rock State Park in northwestern Illinois during May-August 1991. Raccoons, Procyon lotor L., and opossums, Didelphis virginiana Kerr, were infested with the highest larval densities and were trapped primarily in bottomland forest and ecotone habitats. All species had similar nymphal densities, except the eastern cottontails, Sylvilagus floridanus Allen, which were infested with fewer nymphs. Infestation by I. dammini is reported for the first time for fox squirrels, Sciurus niger E. G. St. Hilaire, and for the first time in the midwestern United States for blue jays, C. cristata. These two species were hosts for nymphs in upland forest habitat. Molting rates varied among ticks that fed on different host species and among larvae that fed on individuals of the same species. Molting rate is proposed as an important factor in determining the relative importance of a host species to I. dammini population dynamics. PMID:8254647

  8. 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. PMID:18676138

  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. Home treatment of patients with small to medium sized acute pulmonary embolism.

    PubMed

    Elf, J E; Jögi, J; Bajc, M

    2015-02-01

    Most patients with acute pulmonary embolism (PE) are still treated as inpatients. This is a retrospective cohort study of patients with acute PE, diagnosed using V/P SPECT between 2007 and 2011. Patients were treated at home if they were hemodynamically stable, did not require oxygen or parenteral analgetics, had no contraindications to anticoagulant treatment and V/P SPECT showed an extension of the PE of less than 40%. The aim of the study was to evaluate the efficacy and safety of home treatment with our algorithm. During the study period 416 outpatients were diagnosed with acute symptomatic PE of whom in total 260 (62.5%) were discharged home from the emergency unit and another 47 (11%) within 24 h from admission. During 3 months follow-up one (0.3%) patient had a recurrent thrombotic event. Eleven (3.6%) patients had a major or clinically relevant bleed and the overall mortality was 2% (n = 6). There were no PE-related mortality. Home treatment should be considered and is safe in the majority of hemodynamically stable outpatients with small to medium size PE, quantified using V/P SPECT. PMID:24942995

  11. Energy conserved and costs saved by small and medium-size manufacturers, 1988--1989

    SciTech Connect

    Kirsch, F.W.

    1991-05-01

    Energy Analysis and Diagnostic Centers (EADCs) provided energy-conserving and cost saving assistance in 339 small and medium-size manufacturing plants nationwide during 1988-89. This report presents the results of what was recommended to those manufacturers, the record of what was implemented by them, and an analysis of the financial rewards gained by them. It also includes an accounting of the financial returns to the federal government, derived from taxes upon the cost savings, or incremental income, of the manufacturers who implement the EADCs` recommendations. EADCs collect implementation data within a year of the energy audit, and for these results that time period extended through 1990. The EADCs are located at accredited engineering departments of universities and staffed by faculty and students. At present there are 18 EADCs serving manufacturers in 37 states; of these, two were established as a result of the 1989 competition, and five more were chosen competitively in 1990. Most of the results in this report were generated by 11 EADCs (named in the Appendix); two others withdrew voluntarily after completing only 10 energy audits during 1988-89. Primary responsibility for selecting, training, evaluating, and managing the EADCs belongs to the Industrial Technology and Energy Management (ITEM) division of University City Science Center (UCSC). The Department of Energy`s Office of Industrial Technologies sponsors the EADC program through an agreement with UCSC.

  12. 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. PMID:24364995

  13. 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. PMID:26654679

  14. 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.

  15. 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. PMID:23958284

  16. 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.

  17. 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.

  18. 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

  19. Methotrexate and etanercept-induced primary cutaneous CD4 positive small/medium-sized pleomorphic T-cell lymphoma*

    PubMed Central

    MA, Han; Qiu, Shu; Lu, Rongbiao; Feng, Peiying; Lu, Chun

    2016-01-01

    Immunosuppressive drugs and biological agents may represent a potential risk of lymphoma development in patients with rheumatoid arthritis. But most cases are diffuse, large B-cell lymphomas. Primary cutaneous CD4+ small/medium-sized pleomorphic T-cell lymphoma, a provisional entity in the 2005 WHO-EORTC classification of cutaneous lymphomas, is only described in a limited number of reports. To our knowledge, our case is a rare instance of primary cutaneous CD4+ small/medium-sized pleomorphic T-cell lymphoma, after associated treatment with methotrexate and etanercept, in a patient with moderate rheumatoid arthritis who had undergone an orchidectomy incorrectly.

  20. 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)...

  1. 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...

  2. 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

    ... quota for spiny dogfish for the 2010 fishing year is 15 million lb (6,803.89 mt) (74 FR 36012, June 24... 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...

  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 648.239 - 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...

  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 622.453 - Prohibition on harvest of egg-bearing spiny lobster.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... spiny lobster. 622.453 Section 622.453 Wildlife and Fisheries FISHERY CONSERVATION AND MANAGEMENT... MEXICO, AND SOUTH ATLANTIC Spiny Lobster Fishery of Puerto Rico and the U.S. Virgin Islands § 622.453 Prohibition on harvest of egg-bearing spiny lobster. (a) Egg-bearing spiny lobster in the Caribbean EEZ...

  7. 50 CFR 622.453 - Prohibition on harvest of egg-bearing spiny lobster.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... spiny lobster. 622.453 Section 622.453 Wildlife and Fisheries FISHERY CONSERVATION AND MANAGEMENT... MEXICO, AND SOUTH ATLANTIC Spiny Lobster Fishery of Puerto Rico and the U.S. Virgin Islands § 622.453 Prohibition on harvest of egg-bearing spiny lobster. (a) Egg-bearing spiny lobster in the Caribbean EEZ...

  8. Loss of the thyroid hormone-binding protein Crym renders striatal neurons more vulnerable to mutant huntingtin in Huntington's disease.

    PubMed

    Francelle, Laetitia; Galvan, Laurie; Gaillard, Marie-Claude; Guillermier, Martine; Houitte, Diane; Bonvento, Gilles; Petit, Fanny; Jan, Caroline; Dufour, Noëlle; Hantraye, Philippe; Elalouf, Jean-Marc; De Chaldée, Michel; Déglon, Nicole; Brouillet, Emmanuel

    2015-03-15

    The mechanisms underlying preferential atrophy of the striatum in Huntington's disease (HD) are unknown. One hypothesis is that a set of gene products preferentially expressed in the striatum could determine the particular vulnerability of this brain region to mutant huntingtin (mHtt). Here, we studied the striatal protein µ-crystallin (Crym). Crym is the NADPH-dependent p38 cytosolic T3-binding protein (p38CTBP), a key regulator of thyroid hormone (TH) T3 (3,5,3'-triiodo-l-thyronine) transportation. It has been also recently identified as the enzyme that reduces the sulfur-containing cyclic ketimines, which are potential neurotransmitters. Here, we confirm the preferential expression of the Crym protein in the rodent and macaque striatum. Crym expression was found to be higher in the macaque caudate than in the putamen. Expression of Crym was reduced in the BACHD and Knock-in 140CAG mouse models of HD before onset of striatal atrophy. We show that overexpression of Crym in striatal medium-size spiny neurons using a lentiviral-based strategy in mice is neuroprotective against the neurotoxicity of an N-terminal fragment of mHtt in vivo. Thus, reduction of Crym expression in HD could render striatal neurons more susceptible to mHtt suggesting that Crym may be a key determinant of the vulnerability of the striatum. In addition our work points to Crym as a potential molecular link between striatal degeneration and the THs deregulation reported in HD patients. PMID:25398949

  9. Comparison of microperc and mini-percutaneous nephrolithotomy for medium-sized lower calyx stones.

    PubMed

    Tok, Adem; Akbulut, Fatih; Buldu, Ibrahim; Karatag, Tuna; Kucuktopcu, Onur; Gurbuz, Gokhan; Istanbulluoglu, Okan; Armagan, Abdullah; Tepeler, Abdulkadir; Tasci, Ali Ihsan

    2016-04-01

    The objective of this study was to present the outcomes of comparative clinical study of microperc versus mini-percutaneous nephrolithotomy (mini-PNL) in the treatment of lower calyx stones of 10-20 mm. Patients with lower calyx stones treated with microperc (Group-1) or mini-PNL (Group-2) between 2011 and 2014 were retrospectively analyzed. Demographics of the patients were compared, including age, gender, BMI, stone size, laterality and procedural parameters (operation and fluoroscopy time), and outcomes (success and complication rates). A total of 98 patients were evaluated, assigned to Group-1 (n = 58) and to Group-2 (n = 40). Groups were statistically similar in terms of age, stone size, and BMI (p = 0.3, 0.07, 0.6, respectively). The mean procedure and fluoroscopy duration for Group-1 were 43.02 ± 27.98 min and 112.05 ± 72.5 s, and 52.25 ± 23.09 min and 138.53 ± 56.39 s in Group-2 (p = 0.006 and 0.006). The mean hematocrit drop was significantly higher in Group-2 compared to Group-1 (3.98 vs. 1.96%; p < 0.001); however, none of the cases required blood transfusion. Overall complication rates exhibited no statistically significant difference (p = 0.57). Stone-free status was similar (86.2 vs. 82.5%, p = 0.66). The tubeless procedure rate was significantly higher in Group-1 (p < 0.001). In Group-2, duration of hospitalization was significantly longer than in Group-1 (2.63 vs. 1.55 days; p < 0.01). Outcomes of the present retrospective study show that microperc is a treatment option for medium-sized lower calyx stone, being associated with lower blood loss, procedure, reduced fluoroscopy and hospitalization time, and a higher tubeless rate. PMID:26194110

  10. 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. PMID:24645441

  11. 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. PMID:27068422

  12. Are fragment-based quantum chemistry methods applicable to medium-sized water clusters?

    PubMed

    Yuan, Dandan; Shen, Xiaoling; Li, Wei; Li, Shuhua

    2016-06-28

    Fragment-based quantum chemistry methods are either based on the many-body expansion or the inclusion-exclusion principle. To compare the applicability of these two categories of methods, we have systematically evaluated the performance of the generalized energy based fragmentation (GEBF) method (J. Phys. Chem. A, 2007, 111, 2193) and the electrostatically embedded many-body (EE-MB) method (J. Chem. Theory Comput., 2007, 3, 46) for medium-sized water clusters (H2O)n (n = 10, 20, 30). Our calculations demonstrate that the GEBF method provides uniformly accurate ground-state energies for 10 low-energy isomers of three water clusters under study at a series of theory levels, while the EE-MB method (with one water molecule as a fragment and without using the cutoff distance) shows a poor convergence for (H2O)20 and (H2O)30 when the basis set contains diffuse functions. Our analysis shows that the neglect of the basis set superposition error for each subsystem has little effect on the accuracy of the GEBF method, but leads to much less accurate results for the EE-MB method. The accuracy of the EE-MB method can be dramatically improved by using an appropriate cutoff distance and using two water molecules as a fragment. For (H2O)30, the average deviation of the EE-MB method truncated up to the three-body level calculated using this strategy (relative to the conventional energies) is about 0.003 hartree at the M06-2X/6-311++G** level, while the deviation of the GEBF method with a similar computational cost is less than 0.001 hartree. The GEBF method is demonstrated to be applicable for electronic structure calculations of water clusters at any basis set. PMID:27263629

  13. Maximum urban heat island intensity in a medium-sized coastal Mediterranean city

    NASA Astrophysics Data System (ADS)

    Papanastasiou, Dimitris K.; Kittas, Constantinos

    2012-02-01

    This paper studies the maximum intensity of the urban heat island (UHI) that develops in Volos urban area, a medium-sized coastal city in central Greece. The maximum temperature difference between the city center and a suburb is 3.4°C and 3.1°C during winter and summer, respectively, while during both seasons the average maximum UHI intensity is 2.0°C. The UHI usually starts developing after sunset during both seasons. It could be attributed to the different nocturnal radiative cooling rate and to the different anthropogenic heat emission rate that are observed at the city center and at the suburb, as well as to meteorological conditions. The analysis reveals that during both seasons the daily maximum hourly (DMH) UHI intensity is positively correlated with solar radiation and with previous day's maximum hourly UHI intensity and negatively correlated with wind speed. It is also negatively correlated with relative humidity during winter but positively correlated with it during summer. This difference could be attributed to the different mechanisms that mainly drive humidity levels (i.e., evaporation in winter and sea breeze (SB) in summer). Moreover, it is found that SB development triggers a delay in UHI formation in summer. The impact of atmospheric pollution on maximum UHI intensity is also examined. An increase in PM10 concentration is associated with an increase in maximum UHI intensity during winter and with a decrease during summer. The impact of PM10 on UHI is caused by the attenuation of the incoming and the outgoing radiation. Additionally, this study shows that the weekly cycle of the city activities induces a weekly variation in maximum UHI intensity levels. The weekly range of DMH UHI intensity is not very large, being more pronounced during winter (0.4°C). Moreover, a first attempt is made to predict the DMH UHI intensity by applying regression models, whose success is rather promising.

  14. 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

  15. 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

  16. High-Resolution Spectroscopic Studies of Complexes Formed by Medium-Size Organic Molecules.

    PubMed

    Becucci, Maurizio; Melandri, Sonia

    2016-05-11

    A wealth of structural and dynamical information has been obtained in the last 30 years from the study of high-resolution spectra of molecular clusters generated in a cold supersonic expansion by means of highly resolved spectroscopic methods. The data obtained, generally lead to determination of the structures of stable conformations. In addition, in the case of weakly bound molecular complexes, it is usual to observe the effects of internal motions due to the shallowness of the potential energy surfaces involved and the flexibility of the systems. In the case of electronic excitation experiments, also the effect of electronic distribution changes on both equilibrium structures and internal motions becomes accessible. The structural and dynamical information that can be obtained by applying suitable theoretical models to the analysis of these unusually complex spectra allows the determination and understanding of the driving forces involved in formation of the molecular complex. In this way, many types of non-covalent interactions have been characterized, from pure van der Waals interactions in complexes of rare gases to moderate-strength and weak hydrogen bonds and to the most recent halogen bonds and n-π interactions. The aim of this review is to underline how the different experimental and theoretical methods converge in giving a detailed picture of weak interactions in small molecular adducts involving medium-size molecules. The conclusions regarding geometries and energies can contribute to understanding of the different driving forces involved in the dynamics of the processes and can be exploited in all fields of chemistry and biochemistry, from design of new materials with novel properties to rational design of drugs. PMID:26986455

  17. Fox baiting against Echinococcus multilocularis: contrasted achievements among two medium size cities.

    PubMed

    Comte, S; Raton, V; Raoul, F; Hegglin, D; Giraudoux, P; Deplazes, P; Favier, S; Gottschek, D; Umhang, G; Boué, F; Combes, B

    2013-08-01

    In Europe, most cities are currently colonized by red foxes (Vulpes vulpes), which are considered to be the main definitive host of the zoonotic cestode Echinococcus multilocularis. The risk of transmission to humans is of particular concern where high fox populations overlap with high human populations. The distribution of baits containing praziquantel has successfully reduced the infection pressure in rural areas and in small plots within large cities. The purpose of this study was to assess its efficiency in two medium size cities (less than 100,000 inhabitants) in areas of high human alveolar echinococcosis incidence. From August 2006 to March 2009, 14 baiting campaigns of praziquantel treatment were run in Annemasse and Pontarlier (Eastern France), each of which encompassed 33 km(2), with a density of 40 baits/km(2). The bait consumption appeared to be lower in strictly urban context compared to suburban areas (78.9% vs. 93.4%) and lower in Annemasse than in Pontarlier (82.2% vs. 89.5%). During our study, the prevalence of E. multilocularis, as assessed by EM-ELISA on fox faeces collected in the field in Annemasse, was lower within the treated area than in the rural control area. A "before/during" treatment comparison revealed a significant decrease of spring prevalence from 13.3% to 2.2%. No significant change in prevalence was detected in Pontarlier (stable prevalence: 9.1%) where the contamination of the treated area followed the temporal trend observed in the control area. There, a greater resilience of the parasite's life cycle, probably due to a strong pressure of recontamination from outside the treated area, may have counteracted the prophylaxis treatment. These contrasted outcomes suggest that the frequency of fox anthelmintic treatment should be adapted to the local situation. PMID:23642656

  18. Lateral plume spreading in a medium size river plume using surface Lagrangian drifters

    NASA Astrophysics Data System (ADS)

    Kakoulaki, Georgia; MacDonald, Daniel; Cole, Kelly

    2016-04-01

    Groups of 27 Lagrangian drifters deployed in the Merrimack River plume over twelve tides, with river discharges ranging between 150-800 m3/s, are used to understand the external forcing mechanisms responsible for the extent of spreading in river plumes. The transition of buoyant flow from a confined estuary to an unconfined coastal ocean introduces the complicated phenomenon of lateral spreading, which occurs preferentially near the surface and results in a flow that spreads laterally as plume water propagates forward in the direction of mean flow. In this work, the temporal and spatial scales of the active spreading region are estimated in the sampled plumes and related to environmental parameters at the river mouth such as inflow river discharge, initial drifter velocity at the point of release, initial reduced gravity and initial internal wave speed. The initial wave speed was found to be the environmental parameter that best predicts the magnitude of the spatial and temporal scales of the active spreading region. Previous studies have asserted the importance of initial plume parameters in near-field plume evolution and here we extrapolate this idea to the mid-field. Interestingly, we find that that lateral plume spreading is arrested at approximately one inertial radius from the river mouth. We therefore propose that the shutdown of spreading is controlled almost exclusively by Coriolis force and it is responsible for converting spreading motion to spinning motion after the mid field region. The outcomes of this research are widely applicable to other energetic, medium size river plume systems and to the author's knowledge this is the first study to estimate lateral plume expansion using observations beyond the immediate near field region of a river plume. This work will provide further development in understanding plume dynamics and the fundamental physical processes that influence coastal ecosystems.

  19. Temperature and relative humidity distributions in a medium-size administrative town in southwest Nigeria.

    PubMed

    Akinbode, O M; Eludoyin, A O; Fashae, O A

    2008-04-01

    This study was carried out in one of the medium-sized public administrative towns in the southwestern part of Nigeria. Its aim is to highlight the effect of spatial distribution of settlements, population, and socio-economic activities on urban air temperature and humidity in the town. Temperature and relative humidity data from 1992 to 2001 were obtained from three meteorological stations in Akure, the Administrative Capital of Ondo State, Nigeria. The stations are located within the Federal Ministry of Aviation, Akure Airport (FMA), Federal University of Technology, Akure (FUTA) and Federal School of Agriculture (SOA). Air temperature and relative humidity measurements were also obtained from 27 points, which were cited to include road junctions, markets, built up areas, etc., using sling psychrometer. The data were subsequently analysed for spatial and temporal variations using statistical packages (SPSS and Microsoft Excel) and isolines. Actual vapour pressure and dew point temperature were computed using Magnus conversion formulae. The results obtained showed that spatial variation was insignificant, in terms of the temperature and humidity variables. The annual mean temperature (Tmean) ranged between 21.9 and 30.4 degrees C while minimum (Tmin) and maximum (Tmax) temperatures varied from 13 to 26 and 21.5-39.6 degrees C, respectively. Relative humidity (RH), actual vapour pressure (Es) and dew point temperature (Td) values also varied from 39.1% to 98.2%, 19.7-20.8 gm(-3), and 17.3-17.8 degrees C, respectively. A significant relationship (p>0.6; r<0.05) between Tmin, Es and Td was observed while the daytime 'urban heat island' intensity (UHI) ranged between 0.5 and 2.5 degrees C within the study period. The study concluded that there is influence of urban canopy on the microclimate of Akure, and hypothesizes that the urban dwellers may be subjected to some levels of weather related physiological disorderliness. PMID:17482750

  20. 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…

  1. 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…

  2. 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 involved surveys of…

  3. 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 treatment steps to small, medium-size and large water systems. 141.81 Section 141.81 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) WATER PROGRAMS (CONTINUED) NATIONAL PRIMARY DRINKING WATER REGULATIONS Control of Lead and...

  4. 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 such a way…

  5. Is Small Finally Becoming Beautiful? Small and Medium-Size Enterprises in the New Economy. IES Report.

    ERIC Educational Resources Information Center

    Dejonckheere, J.; Ramioul, M.; Van Hootegem, G.

    This report addresses small and medium-sized enterprises' (SMEs') role in the changing international division of labor and trade in information service activities. Chapter 2 describes the EMERGENCE project to map and measure eWork. Chapter 3 reviews literature that shows SMEs account for the overwhelming majority of companies and make a crucial…

  6. 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 in Central…

  7. 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 treatment steps to small, medium-size and large water systems. 141.81 Section 141.81 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) WATER PROGRAMS (CONTINUED) NATIONAL PRIMARY DRINKING WATER REGULATIONS Control of Lead and...

  8. 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…

  9. 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. PMID:26906914

  10. 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 developed a…

  11. Concept of an Exchange Network for the Development of Vocational Training in Small and Medium-Sized Enterprises.

    ERIC Educational Resources Information Center

    Boudet, Rene

    An examination of the ways in which vocational training can be extended to small and medium-sized enterprises in the European Economic Community, this document consists of: an introduction; four parts containing multiple chapters; 10 case studies; and a bibliography. Following the introduction, which is an update of a report made in 1985, part one…

  12. 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.…

  13. 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

  14. Rupture process of four medium-sized earthquakes that occurred in the Gulf of California

    NASA Astrophysics Data System (ADS)

    RodríGuez-Lozoya, HéCtor E.; Quintanar, Luis; Ortega, Roberto; Rebollar, Cecilio J.; Yagi, Yuji

    2008-10-01

    Four medium-sized earthquakes (Mw Global CMT project 5.5, 5.6, 5.9, 6.3; hereinafter named Topolobampo, Angel de la Guarda, San Lorenzo, and Loreto earthquakes, respectively) located in the Gulf of California Extensional Province were studied to obtain their kinematic rupture processes. A network of broadband seismic stations located around the Gulf of California recorded the events (Network of Autonomously Recording Seismographs-Baja and Red Sísmica de Banda Ancha). Inversion of the seismic moment tensor and body waveform modeling were used to obtain the fault geometry and slip distribution on the fault plane, respectively. From these analyses, we obtained source depths of the order of 5.5 ± 0.5 km. We found also that the source rupture processes of the Topolobampo and Angel de la Guarda events have simple moment rate functions and source time durations of 5.0 ± 1.2 and 4.2 ± 1.2 s, respectively. The Topolobampo event was a right-lateral strike-slip event, and Angel de la Guarda was a normal event. The San Lorenzo and Loreto shocks show a rather complex rupture, with source time durations of 7.5 ± 1.2 and 9.0 ± 1.2 s, respectively. For these earthquakes, we tested the resolution of numerical results, performing an extra inversion with smoother waveforms. The new inversions do not show the separated patches of slip, as in the first analysis, but the slip distribution has an elongated shape not characteristic of simple events. We cannot therefore conclude rupture propagation for the San Lorenzo event, although the extent of the patch for the Loreto earthquake agrees with aftershock locations. Estimates of source time durations for these earthquakes are at the upper limit of the values found for earthquakes elsewhere. Directions of P axes are in the same order of magnitude as the maximum horizontal stress obtained for the so-called Gulf of California stress province from borehole elongations, focal plane solutions, and fault slip data.

  15. 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

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

    PubMed Central

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

    2013-01-01

    Abstract 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

  17. 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. PMID:24302431

  18. 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

  19. Assessment of metal exposure, ecological status and required water quality monitoring strategies in small- to medium-size temperate rivers.

    PubMed

    Marijić, Vlatka Filipović; Perić, Mirela Sertić; Kepčija, Renata Matoničkin; Dragun, Zrinka; Kovarik, Ivana; Gulin, Vesna; Erk, Marijana

    2016-01-01

    The present study was undertaken to obtain a better understanding of the seasonal variability of total dissolved metal/metalloid levels and physicochemical parameters within small- to medium-size freshwater ecosystems in temperate climate region. The research was conducted in four seasons in the Sutla River, medium-size polluted, and the Črnomerec Stream, small-size unpolluted watercourse in Croatia. In the Sutla River, characterized by the rural/industrial catchment, physicochemical parameters and total dissolved metal concentrations of 21 trace and 4 macro elements were analysed downstream of the point source of pollution, the glass production facility, indicating for the first time their variability across four seasons. Based on dissolved oxygen, total dissolved solids, nutrient concentrations, conductivity and total chemical oxygen demand, quality status of the Sutla River was good, but moderate to poor during summer, what was additionally confirmed by the highest levels of the most of 25 measured metals/metalloids in summer. Comparison with the reference small-size watercourse, the Črnomerec Stream, indicated significant anthropogenic impact on the Sutla River, most evident for Fe, Mn, Mo, Ni, Pb, Rb and Tl levels (3-70-fold higher in the Sutla River across all seasons). Generally, presented results indicated significant decrease of the water quality in the anthropogenically impacted small- to medium-size watercourses in summer, regarding physicochemical water parameters and total dissolved metal/metalloid concentrations, and pointed to significant seasonality of these parameters. Confirmed seasonality of river ecological status indicates that seasonal assessment represents a prerequisite for proper classification of the water quality in small- to medium-size temperate rivers. PMID:26745644

  20. Cocaine-induced dendritic remodeling occurs in both D1 and D2 dopamine receptor-expressing neurons in the nucleus accumbens.

    PubMed

    Li, Juan; Liu, Nuyun; Lu, Kangrong; Zhang, Lei; Gu, Jingjing; Guo, Fukun; An, Shengli; Zhang, Lin; Zhang, Lu

    2012-05-31

    Repeated exposure to cocaine can induce persistent alterations in the brain's reward system, including increases in the number of dendrites and spine density on medium-sized spiny neurons (MSNs) in the nucleus accumbens (NAc). The structural remodeling of dendrites and spines in the NAc is thought to play a critical role in cocaine addiction. MSNs in the NAc can be classified by expression of either D1 or D2 dopamine receptors, which are localized to the direct and indirect pathway, respectively. It is unknown whether the dendritic changes induced by repeated cocaine treatment occur in MSNs of the direct or indirect pathway. Because the traditional Golgi-Cox impregnation of neurons precludes identifying particular subpopulations of MSNs, we performed dendritic morphology analysis after biocytin-labeling and Golgi-Cox impregnation. We found that the biocytin staining MSNs showed higher dendritic spine density and higher number of dendrites than that in Golgi impregnation group. In addition, we found that the increasing spine density induced by repeated cocaine treatment in female mice was higher than that in male mice. Next we used biocytin staining and dynorphin/D2 receptor colocalization to determine which cell type(s) displayed dendritic changes after repeated cocaine treatment. We found that cocaine-induced changes in dendritic parameters occurred in MSNs of both the direct (D1-expressing) and indirect (D2-expressing) pathways. PMID:22561554

  1. Staged Surgery with Total Excision and Lamellar Reconstructive for Medium-sized Divided Nevus of the Eyelids

    PubMed Central

    Li, Qian; Quan, Yadan; Li, Kang; Liu, Jinling

    2015-01-01

    Background: To explore a prior treatment strategy for medium-sized (1.5–20 cm) divided nevus of the eyelids. Methods: Six patients who suffered from divided nevus of eyelids were recruited to this prospective, case series study between July 2008 and January 2014 (4 male and 2 female patients). The patients’ ages ranged from 14 to 29 years, with an average age of 24.5 years. All lesions were medium-sized (1.5–20 cm in diameter) and invaded eyelid margins and the posterior lamella of eyelids. Staged surgery involved total excision of lesions and then repair of the defects with advanced skin flaps and tarsoconjunctival flaps. Two staged surgeries were completed at intervals of at least 3 months. Results: All of the patients were followed up at least 3 months after the second surgery. Malignant transformation and recurrence were not observed. All of the flaps survived well, and all of the donor sites were healed with inconspicuous scarring. The only complication was eyelash sacrifices, and 5 of 6 patients suffered from this complication. Excellent cosmetic results were gained in all patients, with the exception of 1 patient who thought his postoperative appearance was only good because of the impalpable disparity in color and thickness between the skin flaps and recipient sites. Conclusions: A staged surgery approach with the total excision of lesions and lamellar reconstructive procedures to repair the defect is a reasonable treatment strategy and can achieve satisfactory cosmetic results for medium-sized (1.5–20 cm in diameter) divided nevus of eyelid. PMID:26180739

  2. 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

  3. Lowest-energy cage structures of medium-sized (ZnO){sub n} clusters with n = 15 − 24

    SciTech Connect

    Tang, Lingli; Sai, Linwei; Zhao, Jijun; Qiu, Ruifeng

    2015-01-22

    Fullerene-like cage structures of medium-sized (ZnO){sub n} clusters with n = 15 − 24 were generated by spiral algorithm and optimized using density functional theory calculations. Most of these lowest-energy cage structures contain only four-membered and six-membered rings, whereas eight-membered rings were found in the lowest-energy cages of (ZnO){sub n} (n = 19, 20, 23, 24). Our best cage configurations either reproduce or prevail the previously reported ones. The size-dependent electronic properties were also discussed.

  4. Synthesis, antimicrobial activity and molecular docking of novel tetracyclic scaffolds incorporating a flavonoid framework with medium sized oxygen heterocycles.

    PubMed

    Dongamanti, Ashok; Aamate, Vikas Kumar; Devulapally, Mohan Gandhi; Gundu, Srinivas; Kotni, Meena Kumari; Manga, Vijjulatha; Balasubramanian, Sridhar; Ernala, Prasad

    2015-02-15

    A convenient approach for the synthesis of novel tetracyclic scaffolds incorporating a flavonoid framework with medium sized heterocyclic rings (eight-, nine-, ten- and eleven-membered rings) containing two oxygen atoms from flavonols through alkylation using different dibromoalkanes was described. The synthesized compounds were established based on the spectral data and X-ray crystal structure for 6c. The synthesized compounds were evaluated for their in vitro antimicrobial activity. Docking studies were carried out for most active two compounds 6f and 6i. PMID:25592711

  5. 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

    ... (5,443.11 mt) (74 FR 20230, May 1, 2009). The commercial quota is allocated into two periods (May 1... 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...

  6. 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

    ... dogfish for the 2011 fishing year is 20 million lb (9,071.85 mt) (76 FR 32874, June 7, 2011). The... 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...

  7. 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

    ...) (75 FR 36012, June 24, 2010). The commercial quota is allocated into two periods (May 1 through... 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...

  8. 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

    ... dogfish for the 2011 fishing year is 20 million lb (9,071.85 mt) (76 FR 32874, June 7, 2011). The... 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...

  9. Understanding the behavioural phenotype of the precocial spiny mouse.

    PubMed

    Ratnayake, Udani; Quinn, Tracey; Daruwalla, Kerman; Dickinson, Hayley; Walker, David W

    2014-12-15

    The use of the spiny mouse (Acomys cahirinus) in experimental research is steadily increasing, due to the precocial nature of this species and the similarities in endocrinology to the human. The characterisation of normal behavioural traits throughout development has not been comprehensively measured in the spiny mouse. Therefore the aim of this study was to behaviourally phenotype the spiny mouse, with the use of behavioural paradigms commonly used to assess behaviour in rat and mouse models of human behavioural disorders such as autism, attention-deficit disorder, and schizophrenia. Male and female spiny mice were assessed at 1-5, 10-15, 20-25, 40-45 and 80-85 days of age using the open field test, novel object recognition test, rotarod, elevated plus maze, a social interaction test, and prepulse inhibition. Exploratory activity, motor coordination, fear, anxiety and social behaviours could be accurately measured from 1 day of age. Open field exploration and motor coordination on a modified rotarod were precociously developed by 10-15 and 20-25 days of age, respectively, when they were equivalent to the performance of conventional adult mice. Learning and memory (assessed by the novel object recognition test), and sensory gating (prepulse inhibition) could be reliably determined only after 20-25 days of age, and performance on these tests differed significantly between male and female spiny mice, particularly in adulthood. This study characterises the behavioural traits of spiny mice and provides important information about critical periods of behavioural development throughout postnatal life. PMID:25157432

  10. 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. PMID:22308579

  11. 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.

  12. 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

    ... Requirements Spiny Lobster Amendment 1 (July 15, 1987, 52 FR 22659) initially implemented the Federal spiny... 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)...

  13. 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

    ... Spiny Lobster Tail-Separation Permit Requirements Spiny Lobster Amendment 1 (July 15, 1987, 52 FR 22659... Caribbean, Gulf of Mexico, and South Atlantic; Spiny Lobster Fishery of the Gulf of Mexico and South... to implement Amendment 10 to the Fishery Management Plan for the Spiny Lobster Fishery of the Gulf...

  14. 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.

  15. 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. PMID:24533094

  16. ELECTRONIC SPECTROSCOPY OF MEDIUM-SIZED POLYCYCLIC AROMATIC HYDROCARBONS: IMPLICATIONS FOR THE CARRIERS OF THE 2175 A UV BUMP

    SciTech Connect

    Steglich, M.; Jaeger, C.; Rouille, G.; Huisken, F.; Mutschke, H.; Henning, Th. E-mail: Cornelia.Jaeger@uni-jena.de

    2010-03-20

    Mixtures of polycyclic aromatic hydrocarbons (PAHs) have been produced by means of laser pyrolysis. The main fraction of the extracted PAHs was primarily medium-sized, up to a maximum size of 38 carbon atoms per molecule. The use of different extraction solvents and subsequent chromatographic fractionation provided mixtures of different size distributions. UV-VIS absorption spectra have been measured at low temperature by matrix isolation spectroscopy and at room temperature with PAHs as film-like deposits on transparent substrates. In accordance with semi-empirical calculations, our findings suggest that large PAHs with sizes around 50-60 carbon atoms per molecule could be responsible for the interstellar UV bump at 217.5 nm.

  17. 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.

  18. Quantum chemical study of the electronic properties of an Iridium-based photosensitizer bound to medium-sized silver clusters

    NASA Astrophysics Data System (ADS)

    Bokareva, Olga S.; Kühn, Oliver

    2015-08-01

    The equilibrium structures and electronic excitation spectra of the Ir(III) photosensitizer [Ir(ppy)2(bpy)]+ bound to medium-sized silver clusters Agn (n = 19, 20) are investigated using time-dependent density functional theory. The long-range corrected LC-BLYP approach is used with a system-specific range separation parameter. The weak physisorption of the hybrid complexes yields only small changes in the broadened absorption spectra of the hybrid system as compared with its constituents. However, the density of states as well as the fine structure of the spectra is strongly modified upon complexation. It is shown that the standard range separation parameter (0.47 bohr-1) cannot predict these properties correctly and the optimized value of 0.16 bohr-1 should be used instead.

  19. 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

  20. [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. PMID:25204160

  1. Enhancing work motivation for Japanese female nurses in small to medium-sized private hospitals by analyzing job satisfaction.

    PubMed

    Kudo, Yasushi; Kido, Shigeri; Shahzad, Machiko Taruzuka; Shida, Kyoko; Satoh, Toshihiko; Aizawa, Yoshiharu

    2010-03-01

    Proper work environments are important for nurses to feel motivated. We examined the associations between work motivation and job satisfaction among Japanese nurses to improve their motivation. In Japan, relatively small and medium-sized private hospitals play a central role in the healthcare industry. In the present study, the subjects were nurses working in 23 small and medium-sized private hospitals that had 65 to 326 beds. We analyzed 1,116 registered and licensed practical female nurses (average age, 38.3 years; standard deviation, 11.3 years). Many nurses with their specialized nursing skills dedicate themselves to patient care. However, many of these nurses may not be interested in contributing to their hospitals. Nurses may have different opinions regarding dedication to patient care and contribution to their hospitals. Therefore, concerning work motivation, we produced these two different items, "Nurses' dedication to patients" and "Nurses' contribution to their hospitals." We also produced our own original new job satisfaction questionnaire. We found 7 facets of job satisfaction: "Work as specialists," "Workplace safety," "Relationships with superiors," "Work-life balance," "Relationships among nurses," "Communications with physicians," and "Salary." Multiple linear regression analyses show that both "Nurses' dedication to patients" and "Nurses' contribution to their hospitals" were significantly associated with "Work as specialists." Nurses feel their jobs of protecting people's lives and health are valuable. They do not feel motivated only by money. They value the intrinsic nature of their jobs. Creating proper work environments is important for nurses to be able to work as specialists. PMID:20208420

  2. 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.

  3. Development of potential ecological niches in impact-induced hydrothermal systems: The small-to-medium size impacts

    NASA Astrophysics Data System (ADS)

    Versh, Evelin; Kirsimäe, Kalle; Jõeleht, Argo

    2006-12-01

    Effect of meteorite impact on the biological evolution is usually considered by its catastrophic consequences. However, the impacts can create opportunity for other organisms and the structures themselves can serve as suitable ecological niches (oases) for life. In this contribution we present results of modeling of an impact-induced hydrothermal (IHT) system in a small-to-medium sized impact crater, where the development of zones habitable for primitive hydrothermal thermophilic and hypethermophilic microorganisms was studied. The impact and geothermal modeling was verified against the 4-km diameter Kärdla complex structure, Hiiumaa Island, Estonia. If there is an sufficient amount of water present in the target (e.g., sea cover, groundwater or permafrost resources) then the differential temperature fields created by the impact initiate a hydrothermal circulation system within the crater. The results of transient fluid flow and heat transfer simulations in Kärdla suggest that immediately after impact the temperatures in the central area, which contains the most hydrothermal alteration, were well above the boiling point. However, due to efficient heat loss at the groundwater vaporization front, the vapor-dominated area disappears within a few decades. In the central uplift area, the conditions favorable for thermophilic microorganisms (temperatures <100 °C) were reached in 500-1000 years after the impact. The overall cooling to ambient temperatures in the deeper parts of the central uplift lasted for thousands of years. In the crater depression and rim area the initial temperatures, suggested by the impact modeling, were much lower - from 150 °C to ambient temperatures, except locally in fracture zones and suevite pockets. Our data suggest that in small-to-medium size impact craters with insignificant melting, the suitable conditions for hydrothermal microbial communities are established shortly (tens to few hundreds of years as maximum) after the impact in

  4. Loss of the thyroid hormone-binding protein Crym renders striatal neurons more vulnerable to mutant huntingtin in Huntington's disease

    PubMed Central

    Francelle, Laetitia; Galvan, Laurie; Gaillard, Marie-Claude; Guillermier, Martine; Houitte, Diane; Bonvento, Gilles; Petit, Fanny; Jan, Caroline; Dufour, Noëlle; Hantraye, Philippe; Elalouf, Jean-Marc; De Chaldée, Michel; Déglon, Nicole; Brouillet, Emmanuel

    2015-01-01

    The mechanisms underlying preferential atrophy of the striatum in Huntington's disease (HD) are unknown. One hypothesis is that a set of gene products preferentially expressed in the striatum could determine the particular vulnerability of this brain region to mutant huntingtin (mHtt). Here, we studied the striatal protein µ-crystallin (Crym). Crym is the NADPH-dependent p38 cytosolic T3-binding protein (p38CTBP), a key regulator of thyroid hormone (TH) T3 (3,5,3′-triiodo-l-thyronine) transportation. It has been also recently identified as the enzyme that reduces the sulfur-containing cyclic ketimines, which are potential neurotransmitters. Here, we confirm the preferential expression of the Crym protein in the rodent and macaque striatum. Crym expression was found to be higher in the macaque caudate than in the putamen. Expression of Crym was reduced in the BACHD and Knock-in 140CAG mouse models of HD before onset of striatal atrophy. We show that overexpression of Crym in striatal medium-size spiny neurons using a lentiviral-based strategy in mice is neuroprotective against the neurotoxicity of an N-terminal fragment of mHtt in vivo. Thus, reduction of Crym expression in HD could render striatal neurons more susceptible to mHtt suggesting that Crym may be a key determinant of the vulnerability of the striatum. In addition our work points to Crym as a potential molecular link between striatal degeneration and the THs deregulation reported in HD patients. PMID:25398949

  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. PMID:21698534

  6. 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.

  7. 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.

  8. 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.

  9. Feeding a medium size PAFC generator with hydrogen obtained by the fermentation of biomasses: A preliminary analysis

    SciTech Connect

    Ascoli, A.; Palumbo, P.; Sorlini, C.; Fancellu, G.

    1997-07-01

    The largest (1.3 MW nominal power) fuel cell generator in Europe is now under test at the Bicocca plant of Aem, the Milan Municipality Energy Utility. It is a phosphoric acid fuel cell (PAFC) generator, fed by pipeline methane through a reformer, and grid connected through an inverter. PAFC generators in general can also be fed, through a reformer, by a methane-rich biogas, obtained by the anaerobic digestion of a biomass. The yields of the microbiological treatment of cheese whey utilizing lactose-fermenting bacteria, capable to produce molecular hydrogen, have been tested in different conditions. The effective operation parameter of the Bicocca generator, experimentally observed during its initial test, have been used as the input data to analyze the possibility to feed medium-size PAFC generators by molecular H{sub 2} directly produced by the anaerobic fermentation of cheese whey. On the basis of this data, the actual size of the fermentor that would produce enough H{sub 2} to feed the Bicocca generator has been calculated. It has been also checked, on the basis of the same experimental data, that the entire cheese whey production of Lombardy and Emily regions could be fermented to produce the amount of H{sub 2} necessary to feed the Bicocca generator, leaving low-COD, easily disposable grey waters. This would also solve the problem of conditioning cheese whey for disposal, allowing substantial economies.

  10. Urban farming and malaria risk factors in a medium-sized town in Cote d'Ivoire.

    PubMed

    Matthys, Barbara; Vounatsou, Penelope; Raso, Giovanna; Tschannen, Andres B; Becket, Emmanuel Gbede; Gosoniu, Laura; Cissé, Gueladio; Tanner, Marcel; N'goran, Eliézer K; Utzinger, Jürg

    2006-12-01

    Urbanization occurs at a rapid pace across Africa and Asia and affects people's health and well-being. A typical feature in urban settings of Africa is the maintenance of traditional livelihoods, including agriculture. The purpose of this study was to investigate malaria risk factors in urban farming communities in a medium-sized town in Côte d'Ivoire. Two cross-sectional surveys were carried out among 112 households from six agricultural zones. First, the heads of households were interviewed on agricultural land use, farming practices, water storage, sanitation facilities, and socioeconomic status. Second, a finger prick blood sample was taken from all household members and examined for the occurrence and density of Plasmodia. Geographic coordinates of houses, farming plots, and potential mosquito breeding sites were recorded and integrated into a geographic information system. Predictors of Plasmodium falciparum parasitemia were assessed using non-random and random effects Bayesian regression models. The overall prevalence of P. falciparum was 32.1%. In children < 15 years of age, risk factors for a P. falciparum infection included living in a specific agricultural zone, close proximity to permanent ponds and fish ponds, periodic stays overnight in temporary farm huts, and low socioeconomic status. Our findings indicate that specific crop systems and specific agricultural practices may increase the risk of malaria in urban settings of tropical Africa. PMID:17172397

  11. Results and developments from the 12m Davies-Cotton medium-sized telescope prototype for the Cherenkov Telescope Array

    NASA Astrophysics Data System (ADS)

    Oakes, Louise; Garczarcyk, Markus; Schlenstedt, Stefan; Sternberger, Ronny; Schwanke, Ullrich

    2015-09-01

    The Cherenkov Telescope Array (CTA) will be the next generation ground-based observatory for gamma-ray astronomy, covering an energy range from a few tens of GeV to a few hundred TeV. The CTA project is currently in the design and prototyping phase, the start of construction is planned for 2016. The planned sensitivity of CTA improves on current ground based Cherenkov telescope experiments by about an order of magnitude. In the core energy range this sensitivity will be dominated by up to 40 Medium-Sized Telescopes (MSTs). These telescopes, of a modified Davies-Cotton mount type with a reflector diameter of 12 m, are currently being prototyped. A full-size mechanical prototype has been operating in Berlin since 2012. Several types of prototype mirrors have been developed and tested, and are mounted on the telescope. CCD cameras with various lenses are mounted on the prototype for studying deformation of the structure, testing alignment techniques, and telescope pointing using astrometry methods. The report will focus on results of optical and structural measurements, commissioning and testing of the MST prototype in Berlin, as well as the final design.

  12. 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. PMID:25120949

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

    PubMed

    Mátyus, Edit; Simunek, Ján; Császár, Attila G

    2009-08-21

    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 (12)CH(4) and (12)CH(2)D(2) isotopologues of the methane molecule. The largest matrix handled on a personal computer during these computations is of the size of (4x10(8))x(4x10(8)). 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. PMID:19708731

  14. Uncertainties of Completeness Measures in Openstreetmap - a Case Study for Buildings in a Medium-Sized German City

    NASA Astrophysics Data System (ADS)

    Törnros, T.; Dorn, H.; Hahmann, S.; Zipf, A.

    2015-08-01

    The completeness of buildings in OpenStreetMap (OSM) is estimated for a medium-sized German city and its surroundings by comparing the OSM data with data from an official building cadastre. As completeness measures we apply two unit-based methods that are frequently applied in similar studies. It is found that the estimation of OSM building completeness strongly differ between the methods. A count ratio (number of OSM buildings / number of reference buildings) tends to underestimate the actual building completeness and an area ratio (total OSM building area / total reference building area) instead tends to overestimate the completeness within the study area. It is argued that a simple pre-processing of the building footprint polygons leads to a more accurate completeness estimation when applying the count ratio. It is also suggested to more carefully examine the areas that have been mapped in OSM but not in the reference data set (false positives). In the present study region, these values are mainly due to simplified OSM polygons and they contribute to an overestimation of the OSM building completeness when applying the area ratio.

  15. Small-scale capture, transport and tank adaptation of live, medium-sized Scombrids using "Tuna Tubes".

    PubMed

    Bar, Ido; Dutney, Luke; Lee, Peter; Yazawa, Ryosuke; Yoshizaki, Goro; Takeuchi, Yutaka; Cummins, Scott; Elizur, Abigail

    2015-01-01

    The transport of live fish is a crucial step to establish fish culture in captivity, and is especially challenging for species that have not been commonly cultured before, therefore transport and handling methods need to be optimized and tailored. This study describes the use of tuna tubes for small-scale transport of medium-sized pelagic fish from the Scombridae family. Tuna tubes are an array of vertical tubes that hold the fish, while fresh seawater is pumped up the tubes and through the fish mouth and gills, providing oxygen and removing wastes. In this study, 19 fish were captured using rod and line and 42 % of the captured fish were transported alive in the custom-designed tuna tubes to an on-shore holding tank: five mackerel tuna (Euthynnus affinis) and three leaping bonito (Cybiosarda elegans). Out of these, just three (15.8 % of total fish) acclimatized to the tank's condition. Based on these results, we discuss an improved design of the tuna tubes that has the potential to increase survival rates and enable a simple and low cost method of transporting of live pelagic fish. PMID:26543739

  16. 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

  17. 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

  18. 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. PMID:23393990

  19. 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). PMID:25463858

  20. The Role of Remote Sensing for Sustainable Elephant Management in South Africa. Four Medium Sized Game Reserves as Case Studies

    NASA Astrophysics Data System (ADS)

    Jordaan, M.

    2012-07-01

    Loxodonta africana (African Elephant) are running out of living space so the protection of what space they have is essential. Existing areas of suitable elephant habitat need to be protected not only from human development but from the elephants themselves. As most elephant populations in South Africa are enclosed and multiplying, there is some increasing cause for concern as the damage caused will escalate and could reach unsustainable proportions. This study examined the utilization of satellite images for the detection of elephant induced ecosystem modification. A pilot study was conducted on four medium sized Game Reserves (each ±30 000 ha) in South Africa. The aim was to ascertain the feasibility of using image analysis as instrument by which Game Reserve managers could assess biodiversity richness, habitat loss, and population-habitat viability. NDVI as indicator of primary production in vegetation is one of the instruments used to evaluate whether the carrying capacity for elephants of each Game Reserve has been reached and to compare the current biomass with those of previous years. The study also looked at the use of the woody canopy cover as target for change detection analysis. Spectral characteristics of specific trees species which are known for being preferred by elephants were used to conduct a temporal analysis on satellite images starting from the period when the elephants were re-introduced into each Game Reserve, thus attempting to identify possible impact on the biodiversity of the respective Game Reserves. Images from satellites such as Landsat, SPOT, Quickbird and SumbandilaSAT provided the needed data and maps.

  1. Risk factors for uterine diseases on small- and medium-sized dairy farms determined by clinical, bacteriological, and cytological examinations.

    PubMed

    Prunner, Isabella; Wagener, Karen; Pothmann, Harald; Ehling-Schulz, Monika; Drillich, Marc

    2014-10-01

    The involution process of the postpartum bovine uterus is usually accompanied by invasion of various bacteria. The objectives of this study were to identify the relationship between the postpartum findings as risk factors for clinical endometritis (CE) and subclinical endometritis (SE). Furthermore, the effects of CE or SE on reproductive performance in small- and medium-sized dairy herds were investigated. A total of 400 cows were examined by vaginoscopy for CE at 20 to 30 days postpartum, and samples were collected for cytological examinations for SE and for bacteriology by cytobrush technique. The vaginoscopic and cytological examinations showed that 27.3% and 21.0% of the cows were found with CE and SE, respectively. The bacterial community analyses revealed a large variety of bacteria. Overall, bacteria from the order Actinomycetales, Lactobacillales, Bacillales, Burkholderiales, Caulobacteriales Enterobacteriales, Pasteurellales, and Pseudomonadales were detected, whereas in 39.5% of the samples no bacterial growth was detectable. The uterine pathogens Escherichia coli and Trueperella pyogenes were found in 16.8% and 13.0% of the samples cultivated under aerobic conditions. Other frequently isolated bacteria were Streptococcus spp. (31.3%), Staphylococcus spp. (20.0%), Corynebacterium spp. (16.5%), and Bacillus spp. (10.5%). The infection with T. pyogenes was the most important bacteriological risk factor for the occurrence of CE (odds ratio (OR) = 5.72; 95% CI = 3.07-10.83) and had a detrimental effect on the hazard of nonpregnancy by 200 days postpartum (hazard ratio = 1.66; 95% CI = 1.12-2.46). Calving assistance (OR = 1.79; 95% CI = 1.16-2.98) and farm (OR = 1.11; 95% CI = 1.02-1.20) were indicated as further risk factors for CE and SE. Effects of CE and SE on reproductive performance parameters could not be demonstrated. PMID:25066047

  2. Spinal internuncial neurones in progressive encephalomyelitis with rigidity.

    PubMed Central

    Howell, D A; Lees, A J; Toghill, P J

    1979-01-01

    The clinical and pathological features of a fourth patient with progressive encephalomyelitis with rigidity are reported and compared with those previously described. It is suggested that the muscular rigidity, abnormal postures, painful muscular spasms, and myoclonus are a product of excessive and abnormal discharges of alpha motor neurones caused by their release from control by spinal internuncial neurones. A count of neuronal perikarya in the ventral horns confirmed that the disease selectively destroyed small and medium sized neurones, most of which were spinal internuncial neurones. Experimental, clinical, and pathological evidence concerning spinal internuncial neurones is reviewed and found to conform to this theory. The pathogenesis of opsoclonus may be similar. Images PMID:501376

  3. 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

    ... European Union; Scheduling of an Additional Public Hearing With Simplified Filing Procedures AGENCY: United... Barriers that U.S. Small and Medium-sized Enterprises Perceive as Affecting Exports to the European Union... and Investment Partnership (TTIP) negotiations with the European Union (EU), is seeking to...

  4. 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…

  5. Dossier on Completed and Ongoing Activities in the Field of "Small and Medium-Sized Enterprises." (First Review 1986-1990).

    ERIC Educational Resources Information Center

    Melis, A.

    1991-01-01

    The European Centre for the Development of Vocational Training's (CEDEFOP) activities and research relating to small and medium-sized enterprises (SMEs) have focused on three areas of action: (1) development of training for SMEs; (2) information on the training provision available in the member states; and (3) promotion of the exchange and…

  6. 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"…

  7. 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…

  8. 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…

  9. Analysis and Evaluation of Databases on Business and Management Training Schemes for Small and Medium-Sized Enterprises in the European Community.

    ERIC Educational Resources Information Center

    Allesch, Jurgen; Preiss-Allesch, Dagmar

    This report describes a study that identified major databases in operation in the 12 European Community countries that provide small- and medium-sized enterprises with information on opportunities for obtaining training and continuing education. Thirty-five databases were identified through information obtained from telephone interviews or…

  10. 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) "Russian Empire…

  11. Distribution and function of splash, an achaete-scute homolog in the adult olfactory organ of the Caribbean spiny lobster Panulirus argus.

    PubMed

    Tadesse, Tizeta; Schmidt, Manfred; Walthall, William W; Tai, Phang C; Derby, Charles D

    2011-04-01

    achaete-scute complex (ASC) genes, which encode basic helix-loop-helix transcription factors, regulate embryonic and adult neurogenesis in many animals. In adult arthropods, including crustaceans, ASC homologs have been identified but rarely functionally characterized. We took advantage of the recently identified crustacean homolog, splash (spiny lobster achaete scute homolog), in the olfactory organ of the Caribbean spiny lobster Panulirus argus to examine its role in adult neurogenesis. We tested the hypothesis that splash is associated with but not restricted to sensory neuron formation in the olfactory organ, the antennular lateral flagellum (LF), of adult spiny lobsters. We demonstrated splash labeling in epithelial cells across LF developmental zones (i.e., proliferation and mature zones), in auxiliary cells surrounding dendrites of olfactory receptor neurons (ORNs), and in immature and mature ORNs, but not in granulocytes or chromatophores. Since ORN proliferation varies with molt stage, we examined splash expression across molt stages and found that molt stage affected splash expression in the ORN mature zone but not in the proliferation zone. In vivo incorporation of bromodeoxyuridine (BrdU) showed no correlation in the cellular pattern of splash expression and BrdU labeling. The intensity of splash labeling was dramatically enhanced in the proliferation zones following LF damage, suggesting enhanced splash expression during repair and/or regeneration. We conclude that splash is not closely associated with the formation of sensory neurons under normal physiological conditions, and we propose that splash is involved in repair and regeneration. We also propose that splash has additional roles other than neurogenesis in adult crustaceans. PMID:21394934

  12. 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

    ... million lb (5,443.11 mt) (75 FR 36012, June 24, 2010). In the fall of 2010, the NMFS Northeast Fisheries... Northeastern United States; Proposed 2011 Specifications for the Spiny Dogfish Fishery AGENCY: National Marine... rule; request for comments. SUMMARY: NMFS proposes specifications for the spiny dogfish fishery for...

  13. 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

    ... requirements for the spiny dogfish fishery, and other general administrative requirements (65 FR 1557, January... action was published in the Federal Register on March 17, 2011 (76 FR 14644), with public comment... Northeastern United States; 2011 Specifications for the Spiny Dogfish Fishery AGENCY: National Marine...

  14. 50 CFR 648.239 - Spiny dogfish framework adjustments to management measures.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... management measures. 648.239 Section 648.239 Wildlife and Fisheries FISHERY CONSERVATION AND MANAGEMENT... UNITED STATES Management Measures for the Spiny Dogfish Fishery § 648.239 Spiny dogfish framework adjustments to management measures. (a) Within season management action. The Councils may, at any...

  15. 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

  16. 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

  17. 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

    ..., and South Atlantic; Spiny Lobster Fishery of Puerto Rico and the U.S. Virgin Islands; Exempted Fishing... contracted commercial fishermen to temporarily possess undersized and berried Caribbean spiny lobster for non... would include implanting a tag on each spiny lobster before releasing the lobster with minimal...

  18. Interspecific competition and torpor in golden spiny mice: two sides of the energy-acquisition coin.

    PubMed

    Levy, Ofir; Dayan, Tamar; Kronfeld-Schor, Noga

    2011-09-01

    We studied the occurrence of torpor in golden spiny mice in a hot rocky desert near the Dead Sea. In this rodent assemblage, a congener, the nocturnal common spiny mouse, competitively excluded the golden spiny mouse from the nocturnal part of the diel cycle and forced it into diurnal activity; this temporal partitioning allows the two species to partition their prey populations, particularly in summer when the diet of the two species is comprised mainly of arthropods, and largely overlap. We studied the effect of the presence of the common spiny mice at two resource levels (natural food availability and food added ad libitum) on populations of golden spiny mice in four large outdoor enclosures: two with common spiny mice removed and two enclosures with populations of both species. We hypothesized that with interspecific competition and/or reduced resources, golden spiny mice will increase their use of torpor. As we expected, supplemented food reduced the total time spent torpid. In summer, when the different activity periods of the two species results in prey species partitioning, removal of the congener did not affect torpor in the golden spiny mouse. However, in winter, when insect populations are low and the two species of mice overlap in a largely vegetarian diet, removal of the common spiny mouse reduced torpor in golden spiny mice, whether food was supplemented or not. This result suggests that torpor, a mechanism that allows small mammals to sustain periods of low availability of resources or high energetic requirements, may also help them to tolerate periods of enhanced interspecific competition. This may be a significant short-term mechanism that reduces competition and hence increases fitness, in particular of individuals of the subordinate species whose accessibility to resources may be limited. PMID:21719432

  19. Evaluation of the COSHH Essentials Model with a Mixture of Organic Chemicals at a Medium-Sized Paint Producer

    PubMed Central

    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

  20. 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

  1. Selective Effects of PDE10A Inhibitors on Striatopallidal Neurons Require Phosphatase Inhibition by DARPP-321,2,3

    PubMed Central

    Polito, Marina; Guiot, Elvire; Gangarossa, Giuseppe; Longueville, Sophie; Doulazmi, Mohamed; Valjent, Emmanuel; Hervé, Denis; Girault, Jean-Antoine; Paupardin-Tritsch, Danièle; Castro, Liliana R. V.

    2015-01-01

    Abstract Type 10A phosphodiesterase (PDE10A) is highly expressed in the striatum, in striatonigral and striatopallidal medium-sized spiny neurons (MSNs), which express D1 and D2 dopamine receptors, respectively. PDE10A inhibitors have pharmacological and behavioral effects suggesting an antipsychotic profile, but the cellular bases of these effects are unclear. We analyzed the effects of PDE10A inhibition in vivo by immunohistochemistry, and imaged cAMP, cAMP-dependent protein kinase A (PKA), and cGMP signals with biosensors in mouse brain slices. PDE10A inhibition in mouse striatal slices produced a steady-state increase in intracellular cAMP concentration in D1 and D2 MSNs, demonstrating that PDE10A regulates basal cAMP levels. Surprisingly, the PKA-dependent AKAR3 phosphorylation signal was strong in D2 MSNs, whereas D1 MSNs remained unresponsive. This effect was also observed in adult mice in vivo since PDE10A inhibition increased phospho-histone H3 immunoreactivity selectively in D2 MSNs in the dorsomedial striatum. The PKA-dependent effects in D2 MSNs were prevented in brain slices and in vivo by mutation of the PKA-regulated phosphorylation site of 32 kDa dopamine- and cAMP-regulated phosphoprotein (DARPP-32), which is required for protein phosphatase-1 inhibition. These data highlight differences in the integration of the cAMP signal in D1 and D2 MSNs, resulting from stronger inhibition of protein phosphatase-1 by DARPP-32 in D2 MSNs than in D1 MSNs. This study shows that PDE10A inhibitors share with antipsychotic medications the property of activating preferentially PKA-dependent signaling in D2 MSNs. PMID:26465004

  2. Selective Effects of PDE10A Inhibitors on Striatopallidal Neurons Require Phosphatase Inhibition by DARPP-32(1,2,3).

    PubMed

    Polito, Marina; Guiot, Elvire; Gangarossa, Giuseppe; Longueville, Sophie; Doulazmi, Mohamed; Valjent, Emmanuel; Hervé, Denis; Girault, Jean-Antoine; Paupardin-Tritsch, Danièle; Castro, Liliana R V; Vincent, Pierre

    2015-01-01

    Type 10A phosphodiesterase (PDE10A) is highly expressed in the striatum, in striatonigral and striatopallidal medium-sized spiny neurons (MSNs), which express D1 and D2 dopamine receptors, respectively. PDE10A inhibitors have pharmacological and behavioral effects suggesting an antipsychotic profile, but the cellular bases of these effects are unclear. We analyzed the effects of PDE10A inhibition in vivo by immunohistochemistry, and imaged cAMP, cAMP-dependent protein kinase A (PKA), and cGMP signals with biosensors in mouse brain slices. PDE10A inhibition in mouse striatal slices produced a steady-state increase in intracellular cAMP concentration in D1 and D2 MSNs, demonstrating that PDE10A regulates basal cAMP levels. Surprisingly, the PKA-dependent AKAR3 phosphorylation signal was strong in D2 MSNs, whereas D1 MSNs remained unresponsive. This effect was also observed in adult mice in vivo since PDE10A inhibition increased phospho-histone H3 immunoreactivity selectively in D2 MSNs in the dorsomedial striatum. The PKA-dependent effects in D2 MSNs were prevented in brain slices and in vivo by mutation of the PKA-regulated phosphorylation site of 32 kDa dopamine- and cAMP-regulated phosphoprotein (DARPP-32), which is required for protein phosphatase-1 inhibition. These data highlight differences in the integration of the cAMP signal in D1 and D2 MSNs, resulting from stronger inhibition of protein phosphatase-1 by DARPP-32 in D2 MSNs than in D1 MSNs. This study shows that PDE10A inhibitors share with antipsychotic medications the property of activating preferentially PKA-dependent signaling in D2 MSNs. PMID:26465004

  3. Coexistence of vasopressin, neurophysin and noradrenaline immunoreactivity in medium-sized cells of the locus coeruleus and subcoeruleus in the rat.

    PubMed

    Caffé, A R; van Leeuwen, F W; Buijs, R M; de Vries, G J; Geffard, M

    1985-07-01

    Vasopressin-and neurophysin-immunoreactive cells have recently been demonstrated in the rat locus coeruleus (A6) and subcoeruleus (A7). Using consecutive 5 microns thick frozen sections, medium-sized cells throughout the locus coeruleus area, but predominantly in the posterior parts of the A6 displayed coexistence for vasopressin and noradrenaline or neurophysin and noradrenaline immunoreactivity. The putative projection areas of putative fibers from vasopressin-containing cells in the locus coeruleus still remain to be elucidated. PMID:3896392

  4. Experience of Late–Middle-Aged Women who Reside in Small and Medium-Sized Cities in Becoming Psychologically Mature Women

    PubMed Central

    Park, Euna; Kim, Haeok

    2015-01-01

    Objectives The purpose of this study is to search the inner world of postmenopausal women in late-middle age who are facing senescence and live in small and medium-sized cities. Methods The methods of the study were the investigation and classification of answers to questions according to a declarative ethnography analysis. The questions asked to late–middle-aged women living in small and medium-sized cities were “How do you interpret and recognize the changes in the body after menopause?” and “Which methods do you choose and practice to maintain your health in relation to aging during middle age?”. Results Four positive topics and two negative topics were drawn from the study. The four positive themes were: ambition; completion of a great mission; life with a sense of affection; and gratitude for maintaining health. The negative themes were: undulating emotion; and filling the emptiness. Conclusion The recognition of changes in the body after menopause in late–middle-aged women in small and medium-sized cities can affect their preparation processes towards senescence. It is critical to find the means to manage emergency health cases from early adulthood to middle age, based on the outcomes of the study. The study also emphasizes the importance of the woman's family's alternative strategies and supportive systems, which can fit into the cultural context of the community. PMID:26430612

  5. Ultrasonographic fetometry formulas of inner chorionic cavity diameter and biparietal diameter for medium-sized dogs can be used in giant breeds.

    PubMed

    Socha, Piotr; Janowski, Tomasz; Bancerz-Kisiel, Agata

    2015-09-15

    The aim of this study was to evaluate the suitability of the ultrasonographic fetometry method, involving inner chorionic cavity diameter (ICC) and biparietal diameter (BP) measurements, to predict the parturition date in giant breed dogs. Overall, 30 ICC and 24 BP measurements were taken on 24 giant breed bitches. The measured values were substituted into Luvoni and Grioni (2000) formulas for medium-sized bitches because formulas with ICC and BP to dogs with a body mass greater than 40 kg have not been defined. The accuracy of the parturition date predictions proved the method to be highly useful in the observed group of dogs. Prediction accuracy in the giants ranged between 54.16% (± 1 day, using BP) and 90% (± 2 days, using ICC), depending on the parameter measured and precision levels used. Numerically, the results obtained using ICC were better; however, no statistically significant differences between ICC and BP accuracy were found when comparing the effectiveness of the parturition date predictions. Regression lines based on the own fetometric measurements were highly convergent with the lines defined by Luvoni and Grioni (2000) formulas for medium-sized bitches. This outcome suggests a similar gestational development of fetuses in giant dogs and the possible use of Luvoni and Grioni (2000) formulas for medium-sized dogs with breeds weighing greater than 40 kg. PMID:26092700

  6. 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…

  7. 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

  8. Behavioral Immunity Suppresses an Epizootic in Caribbean Spiny Lobsters.

    PubMed

    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

  9. 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

  10. 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. PMID:18506395

  11. Physiology and pharmacology of striatal neurons.

    PubMed

    Kreitzer, Anatol C

    2009-01-01

    The basal ganglia occupy the core of the forebrain and consist of evolutionarily conserved motor nuclei that form recurrent circuits critical for motivation and motor planning. The striatum is the main input nucleus of the basal ganglia and a key neural substrate for procedural learning and memory. The vast majority of striatal neurons are spiny GABAergic projection neurons, which exhibit slow but temporally precise spiking in vivo. Contributing to this precision are several different types of interneurons that constitute only a small fraction of total neuron number but play a critical role in regulating striatal output. This review examines the cellular physiology and modulation of striatal neurons that give rise to their unique properties and function. PMID:19400717

  12. Role of PKA signaling in D2 receptor-expressing neurons in the core of the nucleus accumbens in aversive learning

    PubMed Central

    Yamaguchi, Takashi; Goto, Akihiro; Nakahara, Ichiro; Yawata, Satoshi; Hikida, Takatoshi; Matsuda, Michiyuki; Funabiki, Kazuo; Nakanishi, Shigetada

    2015-01-01

    The nucleus accumbens (NAc) serves as a key neural substrate for aversive learning and consists of two distinct subpopulations of medium-sized spiny neurons (MSNs). The MSNs of the direct pathway (dMSNs) and the indirect pathway (iMSNs) predominantly express dopamine (DA) D1 and D2 receptors, respectively, and are positively and negatively modulated by DA transmitters via Gs- and Gi-coupled cAMP-dependent protein kinase A (PKA) signaling cascades, respectively. In this investigation, we addressed how intracellular PKA signaling is involved in aversive learning in a cell type-specific manner. When the transmission of either dMSNs or iMSNs was unilaterally blocked by pathway-specific expression of transmission-blocking tetanus toxin, infusion of PKA inhibitors into the intact side of the NAc core abolished passive avoidance learning toward an electric shock in the indirect pathway-blocked mice, but not in the direct pathway-blocked mice. We then examined temporal changes in PKA activity in dMSNs and iMSNs in behaving mice by monitoring Förster resonance energy transfer responses of the PKA biosensor with the aid of microendoscopy. PKA activity was increased in iMSNs and decreased in dMSNs in both aversive memory formation and retrieval. Importantly, the increased PKA activity in iMSNs disappeared when aversive memory was prevented by keeping mice in the conditioning apparatus. Furthermore, the increase in PKA activity in iMSNs by aversive stimuli reflected facilitation of aversive memory retention. These results indicate that PKA signaling in iMSNs plays a critical role in both aversive memory formation and retention. PMID:26305972

  13. Genetic deletion of Rhes or pharmacological blockade of mTORC1 prevent striato-nigral neurons activation in levodopa-induced dyskinesia.

    PubMed

    Brugnoli, Alberto; Napolitano, Francesco; Usiello, Alessandro; Morari, Michele

    2016-01-01

    Ras homolog enriched in striatum (Rhes) is a small GTP-binding protein that modulates signal transduction at dopamine receptors, and also activates mammalian target of rapamycin complex 1 (mTORC1). Rhes binding to mTORC1 is hypothesized to play a role in motor disorders such as levodopa-induced dyskinesia. Here, we investigate the behavioral and in vivo neurocircuitry changes associated with genetic deletion of Rhes or inhibition of mTORC1 signaling in the mouse model of levodopa-induced dyskinesia. 6-Hydroxydopamine-hemilesioned Rhes knockout mice and wild-type littermates were chronically treated with levodopa. In parallel, 6-hydroxydopamine-hemilesioned naïve mice were chronically treated with levodopa or levodopa plus rapamycin, to block mTORC1 pathway activation. Dyskinetic movements were monitored during levodopa treatment along with motor activity on the rotarod. Finally, dyskinetic mice underwent microdialysis probe implantation in the dopamine-depleted striatum and ipsilateral substantia nigra reticulata, and GABA and glutamate levels were monitored upon acute challenge with levodopa. Both Rhes knockouts and rapamycin-treated mice developed less dyskinesia than controls, although only rapamycin-treated mice fully preserved rotarod performance on levodopa. Levodopa elevated nigral GABA and glutamate in controls but not in Rhes knockouts or rapamycin-treated mice. Levodopa also stimulated striatal glutamate in controls and Rhes knockouts but not in rapamycin-treated mice. We conclude that both genetic deletion of Rhes and pharmacological blockade of mTORC1 significantly attenuate dyskinesia development by reducing the sensitization of striato-nigral medium-sized spiny neurons to levodopa. However, mTORC1 blockade seems to provide a more favorable behavioral outcome and a wider effect on neurochemical correlates of dyskinesia. PMID:26522958

  14. 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. PMID:25100560

  15. 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. PMID:26858373

  16. Integrated hydrological modelling of small- and medium-sized water storages with application to the upper Fengman Reservoir Basin of China

    NASA Astrophysics Data System (ADS)

    Zhang, C.; Peng, Y.; Chu, J.; Shoemaker, C. A.

    2012-03-01

    Hydrological simulation in regions with a large number of water storages is difficult due to the inaccurate water storage data, including both topologic parameters and operational rules. To address this issue, this paper presents an improved version of SWAT2005 (Soil and Water Assessment Tool, version 2005) using the satellite-based dataset Landsat, an empirical storage classification method, and some empirical relationships to estimate water storage and release from the various levels of flow regulation facilities. The improved SWAT2005 is characterised by three features: (1) a realistic representation of the relationships between the water surface area and volume of each type of water storage, ranging from small-sized ponds for water flow regulation to large-sized and medium-sized reservoirs for water supply and hydropower generation; (2) water balance and transport through a network combining both sequential and parallel streams and storage links; and (3) calibrations for the physical parameters and the human interference parameters. Both the original and improved SWAT2005 are applied to the upper Fengman Reservoir Basin, and the results of these applications are compared. The improved SWAT2005 accurately models small- and medium-sized storages, indicating a significantly improved performance from that of the original model in reproducing streamflows.

  17. Host associations of ticks (Acari: Ixodidae) parasitizing medium-sized mammals in a Lyme disease endemic area of southern New York.

    PubMed

    Fish, D; Dowler, R C

    1989-05-01

    Ticks of eight medium-sized mammal species were studied in an area of endemic Lyme disease in Westchester County, N.Y., from 1 April 1984 to 31 March 1985. Most (81%) of the 266 total mammal captures were raccoon, Procyon lotor (L.) (47%), opossum, Didelphis virginiana (Kerr) (19%), and striped skunk, Mephitis mephitis Schreber (15%); these host species accounted for 91% of the 1,519 ticks collected. Although the total number of ticks was rather evenly distributed among these mammals, species composition of ticks on each host species differed markedly. Ixodes dammini Spielman, Clifford, Piesman, and Corwin was the most abundant tick species and accounted for 45% (690) of the total ticks collected. Immatures were most prevalent (56%) on opossum, and nearly all (86%) adults were found on this host species. I. cookei Marx was second in abundance (34%) and was most prevalent (60%) on skunk. I. texanus Banks and Dermacentor variabilis (Say) were less abundant (less than 20% collectively) and were most prevalent on raccoon. I. dentatus Marx on eastern cottontail, Sylvilagus floridanus (Allen), and I. marxi Banks on gray squirrel, Sciurus carolinensis Gmelin, were least abundant (less than 2% collectively). The prevalence of I. dammini on medium-sized mammals in southern New York may influence the epizoötiology of Lyme disease. PMID:2724317

  18. 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

    Rappa, Nick S; Radasch, Robert M

    2016-08-01

    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

  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. Venezuelan Equine Encephalitis Virus Infection of Spiny Rats

    PubMed Central

    Carrara, Anne-Sophie; Gonzales, Marta; Ferro, Cristina; Tamayo, Margarita; Aronson, Judith; Paessler, Slobodan; Anishchenko, Michael; Boshell, Jorge

    2005-01-01

    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. PMID:15890116

  1. 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

  2. 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 . PMID:23931640

  3. 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

  4. Tracing Staphylococcus aureus in small and medium-sized food-processing factories on the basis of molecular sub-species typing.

    PubMed

    Koreňová, Janka; Rešková, Zuzana; Véghová, Adriana; Kuchta, Tomáš

    2015-01-01

    Contamination by Staphylococcus aureus of the production environment of three small or medium-sized food-processing factories in Slovakia was investigated on the basis of sub-species molecular identification by multiple locus variable number of tandem repeats analysis (MLVA). On the basis of MLVA profiling, bacterial isolates were assigned to 31 groups. Data from repeated samplings over a period of 3 years facilitated to draw spatial and temporal maps of the contamination routes for individual factories, as well as identification of potential persistent strains. Information obtained by MLVA typing allowed to identify sources and routes of contamination and, subsequently, will allow to optimize the technical and sanitation measures to ensure hygiene. PMID:25229709

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

    PubMed

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

    2016-01-21

    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. PMID:26676095

  6. Fixed-time Insemination in Pasture-based Medium-sized Dairy Operations of Northern Germany and an Attempt to Replace GnRH by hCG.

    PubMed

    Marthold, D; Detterer, J; Koenig von Borstel, U; Gauly, M; Holtz, W

    2016-02-01

    A field study was conducted aimed at (i) evaluating the practicability of a fixed-time insemination regime for medium-sized dairy operations of north-western Germany, representative for many regions of Central Europe and (ii) substituting hCG for GnRH as ovulation-inducing agent at the end of a presynch or ovsynch protocol in an attempt to reduce the incidence of premature luteal regression. Cows of two herds synchronized by presynch and two herds synchronized by ovsynch protocol were randomly allotted to three subgroups; in one group ovulation was induced by the GnRH analog buserelin, in another by hCG, whereas a third group remained untreated. The synchronized groups were fixed-time inseminated; the untreated group bred to observed oestrus. Relative to untreated herd mates, pregnancy rate in cows subjected to a presynch protocol with buserelin as ovulation-inducing agent was 74%; for hCG it was 60%. In cows subjected to an ovsynch protocol, the corresponding relative pregnancy rates reached 138% in the case of buserelin and 95% in the case of hCG. Average service interval was shortened by 1 week in the presynch and delayed by 2 weeks in the ovsynch group. It may be concluded that fixed-time insemination of cows synchronized via ovsynch protocol with buserelin as ovulation-inducing agent is practicable and may help improve efficiency and reduce the work load involved with herd management in medium-sized dairy operations. The substitution of hCG for buserelin was found to be not advisable. PMID:26661056

  7. 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. PMID:14530183

  8. 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

    ... March 12, 2013 (78 FR 15674), with a 15-day public comment period. NMFS received one comment, which is... 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...

  9. 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

    ...: Correction On July 27, 2012 (77 FR 44168, July 27, 2012), incorrect latitudinal coordinates for Lobster Trap... 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...

  10. 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.

  11. 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. PMID:25469229

  12. 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

  13. 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.

  14. The effect of an electronic medicine dispenser on diversion of buprenorphine-naloxone-experience from a medium-sized Finnish city.

    PubMed

    Uosukainen, Hanna; Pentikäinen, Hannu; Tacke, Ulrich

    2013-07-01

    Providing unobserved opioid substitution treatment (OST) safely is a major challenge. This study examined whether electronic medicine dispensers (EMDs) can reduce diversion of take-home buprenorphine-naloxone (BNX) in a medium-sized Finnish city. All BNX treated OST patients in Kuopio received their take-home BNX in EMDs for 4months. EMDs' effect on diversion was investigated using questionnaires completed by patients (n=37) and treatment staff (n=19), by survey at the local needle exchange service and by systematic review of drug screen data from the Kuopio University Hospital. The majority of patients (n=21, 68%) and treatment staff (n=11, 58%) preferred to use EMDs for the safe storage of tablets. Five patients (16%) declared that EMDs had prevented them from diverting BNX. However, EMDs had no detectable effect on the availability or origin of illegal BNX or on the hospital-treated buprenorphine-related health problems. EMDs may improve the safety of storage of take-home BNX, but their ability to prevent diversion needs further research. PMID:23433750

  15. Isolation and characterization of four medium-size disintegrins from the venoms of Central American viperid snakes of the genera Atropoides, Bothrops, Cerrophidion and Crotalus.

    PubMed

    Angulo, Yamileth; Castro, Adriana; Lomonte, Bruno; Rucavado, Alexandra; Fernández, Julián; Calvete, Juan J; Gutiérrez, José María

    2014-12-01

    Four disintegrins were isolated from the venoms of the Central American viperid snakes Atropoides mexicanus (atropoimin), Bothrops asper (bothrasperin), Cerrophidion sasai (sasaimin), and Crotalus simus (simusmin). Purifications were performed by reverse-phase HPLC. The four disintegrins have biochemical characteristics, i.e. molecular mass and location of Cys, which allow their classification within the group of medium-size disintegrins. All of them present the canonical RGD sequence, which determines their interaction with integrins in cell membranes. The disintegrins inhibited ADP and collagen-induced human platelet aggregation, with similar IC50s in the nM range. In addition, disintegrins inhibited the adhesion of an endothelial cell line and a melanoma cell line to the extracellular matrix proteins type I collagen, laminin, fibronectin, and vitronectin, albeit showing variable ability to exert this activity. This study expands the inventory of this family of viperid venom proteins, and reports, for the first time, disintegrins from the venoms of species of the genera Atropoides and Cerrophidion. PMID:25457103

  16. 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. PMID:26878434

  17. Results from an exploratory study to identify the factors that contribute to success for UK medical device small- and medium-sized enterprises.

    PubMed

    Hourd, P C; Williams, D J

    2008-07-01

    This paper reports the results from an exploratory study that sets out to identify and compare the strategic approaches and patterns of business practice employed by 14 UK small- and medium-sized enterprises to achieve success in the medical device sector of the health-care industry. An interview-based survey was used to construct individual case studies of the medical device technology (MDT) companies. A cross-case analysis was performed to search for patterns and themes that cut across these individual cases. Exploratory results revealed the heterogeneity of MDT companies and the distinctive features of the MDT innovation process that emphasize the importance of a strategic approach for achieving milestones in the product development and exploitation process and for creating value for the company and its stakeholders. Recognizing the heterogeneity of MDT companies, these exploratory findings call for further investigation to understand better the influence of components of the MDT innovation process on the commercialization life cycle and value trajectory. This is required to assist start-up or spin-out MDT companies in the UK and worldwide to navigate the critical transitions that determine access to financial and consumer markets and enhance the potential to build a successful business. This will be important not only for bioscience-based companies but also for engineering-based companies aiming to convert their activities into medical devices and the health- and social-care market. PMID:18756690

  18. Integrated hydrological modelling of small- and medium-sized water storages with application to the upper Fengman Reservoir Basin of China

    NASA Astrophysics Data System (ADS)

    Zhang, C.; Peng, Y.; Chu, J.; Shoemaker, C. A.; Zhang, A.

    2012-11-01

    Hydrological simulation in regions with a large number of water storages is difficult due to inaccurate water storage data. To address this issue, this paper presents an improved version of SWAT2005 (Soil and Water Assessment Tool, version 2005) using Landsat, a satellite-based dataset, an empirical storage classification method and some empirical relationships to estimate water storage and release from the various sizes of flow detention and regulation facilities. The SWAT2005 is enhanced by three features: (1) a realistic representation of the relationships between the surface area and volume of each type of water storages, ranging from small-sized flow detention ponds to medium- and large-sized reservoirs with the various flow regulation functions; (2) water balance and transport through a network combining both sequential and parallel streams and storage links; and (3) calibrations for both physical and human interference parameters. Through a real-world watershed case study, it is found that the improved SWAT2005 more accurately models small- and medium-sized storages than the original model in reproducing streamflows in the watershed. The improved SWAT2005 can be an effective tool to assess the impact of water storage on hydrologic processes, which has not been well addressed in the current modelling exercises.

  19. 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

  20. 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

  1. 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

  2. Primary cutaneous CD4+ small to medium-size pleomorphic T-cell lymphoma in a 12-year-old girl.

    PubMed

    Volks, Natalie; Oschlies, Ilske; Cario, Gunnar; Weichenthal, Michael; Fölster-Holst, Regina

    2013-01-01

    Primary cutaneous CD4+ small to medium-size pleomorphic T-cell lymphoma (PCSM-TCL) is a rare disease that has been added as a provisional entity to the World Health Organization European Organization for Research and Treatment of Cancer (WHO-EORTC) classification of lymphomas with primary cutaneous manifestations. Patients commonly present with a solitary nodule or plaque on the head or upper trunk, but are usually otherwise in good health. The prognosis is favorable, but the optimal treatment has not been defined. Recent publications have described the expression of programmed death-1 in PCSM-TCL and T-cell pseudolymphoma, suggesting a diagnostic value of this marker in the differential diagnosis of PCSM-TCL in contrast to other types of cutaneous T-cell lymphoma. We present the case of a 12-year-old girl with a tumor of the right supraorbital area. She was treated as an outpatient four times with intralesional triamcinolone acetonide at intervals of 3 to 4 weeks. In addition to the case history, this report includes the clinical and histologic findings and a review of the current literature. PMID:23756295

  3. Development of medium-size half-mask facepiece for male workers at a shipyard and its fit performance in Korea.

    PubMed

    Han, Don-Hee; Kim, David

    2014-01-01

    Ten years ago, three differently sized half-mask facepiece prototypes were constructed from silicon using computer graphics and statistical analysis to fit them according to Korean facial dimensions. The purpose of this study was to complete the medium-size half-mask respirator based on the prototype, which would provide an adequate fit performance for male workers at a shipyard, Hyundai Samho Heavy Industry Co., in Korea. The complete respirator--the hardness 55--was manufactured with existing accessories such as a filter, exhalation valve, and strap attached. The fit performance test was conducted by performing a quantitative fit-test on 48 male subjects: workers who usually wear half-mask respirators (Dobulife Tech Co., Model DM-911, Gwangju, Gyeonggi-do, Korea). The results showed that the hardness 55 provided male subject workers with much better fit performance than the existing mask constructed by the same company. Because softness of the material of the facepiece, in particular the inner part, influenced faceseal leakage, further research on developing better-fit respirator facepieces should consider carefully the fine control of material softness. PMID:24467771

  4. 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 management measures. 648.239 Section 648.239 Wildlife and Fisheries FISHERY CONSERVATION AND MANAGEMENT, NATIONAL OCEANIC AND ATMOSPHERIC ADMINISTRATION, DEPARTMENT OF COMMERCE FISHERIES OF THE NORTHEASTERN UNITED STATES Management Measures for...

  5. 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. PMID:25683612

  6. 50 CFR 648.230 - Spiny dogfish Annual Catch Limits (ACLs).

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... AND ATMOSPHERIC ADMINISTRATION, DEPARTMENT OF COMMERCE FISHERIES OF THE NORTHEASTERN UNITED STATES... commercial spiny dogfish fishery, which shall equal to the domestic ABC (i.e., the ABC minus Canadian catch... is exceeded with a frequency greater than 25 percent (i.e., more than once in 4 years or any...

  7. 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

    ... comment. NMFS proposed the specifications set here in the Federal Register on March 19, 2012 (77 FR 15991... to implement measures to end overfishing and rebuild the spiny dogfish stock. The Mid-Atlantic... corresponds to a 40-percent probability of overfishing) should be more precautionary given the...

  8. Differential sensitivity of medium- and large-sized striatal neurons to NMDA but not kainate receptor activation in the rat.

    PubMed

    Cepeda, C; Itri, J N; Flores-Hernández, J; Hurst, R S; Calvert, C R; Levine, M S

    2001-11-01

    Infrared videomicroscopy and differential interference contrast optics were used to identify medium- and large-sized neurons in striatal slices from young rats. Whole-cell patch-clamp recordings were obtained to compare membrane currents evoked by application of N-methyl-d-aspartate (NMDA) and kainate. Inward currents and current densities induced by NMDA were significantly smaller in large- than in medium-sized striatal neurons. The negative slope conductance for NMDA currents was greater in medium- than in large-sized neurons and more depolarization was required to remove the Mg2+ blockade. In contrast, currents induced by kainate were significantly greater in large-sized neurons whilst current densities were approximately equal in both cell types. Spontaneous excitatory postsynaptic currents occurred frequently in medium-sized neurons but were relatively infrequent in large-sized neurons. Excitatory postsynaptic currents evoked by electrical stimulation were smaller in large- than in medium-sized neurons. A final set of experiments assessed a functional consequence of the differential sensitivity of medium- and large-sized neurons to NMDA. Cell swelling was used to examine changes in somatic area in both neuronal types after prolonged application of NMDA or kainate. NMDA produced a time-dependent increase in somatic area in medium-sized neurons whilst it produced only minimal changes in large interneurons. In contrast, application of kainate produced significant swelling in both medium- and large-sized cells. We hypothesize that reduced sensitivity to NMDA may be due to variations in receptor subunit composition and/or the relative density of receptors in the two cell types. These findings help define the conditions that put neurons at risk for excitotoxic damage in neurological disorders. PMID:11860453

  9. Recruitment of FoxP2-expressing neurons to area X varies during song development.

    PubMed

    Rochefort, Christelle; He, Xiaolu; Scotto-Lomassese, Sophie; Scharff, Constance

    2007-05-01

    In adult songbirds, neural progenitors proliferate along the lateral ventricles. After migration, many of the subsequently formed neuroblasts integrate into the song nuclei HVC and Area X that participate in auditory-guided vocal motor learning and singing. Recruitment of postembryonically generated neurons into HVC, rodent hippocampus, and olfactory bulb has been linked to learning and memory. The cellular identity and the role of postembryonically generated neurons in Area X are unknown. Here we describe that the majority of new neurons in postembryonic Area X of male zebra finches expressed DARPP32 but not choline acetyltransferase or parvalbumin. This suggests that they are spiny neurons. Retrogradely labeled neurons projecting to thalamic nucleus DLM were not renewed. The spiny neurons in Area X were recently shown to express FoxP2, a transcription factor critical for normal speech and language development in humans. Since increased FoxP2 mRNA expression was previously observed during periods of vocal plasticity we investigated whether this increase might be associated with neuronal recruitment. Consistent with their spiny phenotype, new neurons in Area X did express FoxP2 and recruitment increased transiently during the juvenile song learning period. Moreover we found that FoxP2 was expressed in the ventricular zone of adult songbirds but was absent from the germinal zones in adult mouse brains, the hippocampus, and the subventricular zone. Together these results raise the possibility that neuronal recruitment and FoxP2 expression in Area X are associated with vocal learning. PMID:17443826

  10. Vestibular Neuronitis

    MedlinePlus

    ... Prevent Painful Swimmer's Ear Additional Content Medical News Vestibular Neuronitis By Lawrence R. Lustig, MD NOTE: This ... Drugs Herpes Zoster Oticus Meniere Disease Purulent Labyrinthitis Vestibular Neuronitis Vestibular neuronitis is a disorder characterized by ...

  11. 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. PMID:18496614

  12. eVerdEE: a web-based screening life-cycle assessment tool for European small and medium-sized enterprises

    NASA Astrophysics Data System (ADS)

    Naldesi, Luciano; Buttol, Patrizia; Masoni, Paolo; Misceo, Monica; Sára, Balázs

    2004-12-01

    "eLCA" is a European Commission financed project aimed at realising "On line green tools and services for Small and Medium-sized Enterprises (SMEs)". Knowledge and use of Life Cycle Assessment (LCA) by SMEs are strategic to introduce the Integrated Product Policy (IPP) in Europe, but methodology simplification is needed. LCA requires a large amount of validated general and sector specific data. Since their availability and cost can be insuperable barriers for SMEs, pre-elaborated data/meta-data, use of standards and low cost solutions are required. Within the framework of the eLCA project an LCA software - eVerdEE - based on a simplified methodology and specialised for SMEs has been developed. eVerdEE is a web-based tool with some innovative features. Its main feature is the adaptation of ISO 14040 requirements to offer easy-to-handle functions with solid scientific bases. Complex methodological problems, such as the system boundaries definition, the data quality estimation and documentation, the choice of impact categories, are simplified according to the SMEs" needs. Predefined "Goal and Scope definition" and "Inventory" forms, a user-friendly and well structured procedure are time and cost-effective. The tool is supported by a database containing pre-elaborated environmental indicators of substances and processes for different impact categories. The impact assessment is calculated automatically by using the user"s input and the database values. The results have different levels of interpretation in order to identify the life cycle critical points and the improvement options. The use of a target plot allows the direct comparison of different design alternatives.

  13. 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. PMID:27302725

  14. 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.

  15. Comparing capture-recapture methods for estimation of the size of small and medium-sized populations using empirical data on commercial turkey farms in Canada.

    PubMed

    El Allaki, Farouk; Christensen, Jette; Vallières, André

    2015-06-01

    The study objectives were (1) to conduct a systematic review of the performance of capture-recapture methods; (2) to use empirical data to estimate population size in a small-sized population (turkey breeder farms) and a medium-sized population (meat turkey farms) by applying two-source capture-recapture methods (the Lincoln-Petersen, the Chapman, and Chao's lower-bound estimators) and multi-source capture-recapture methods (the log-linear modeling and sample coverage approaches); and (3) to compare the performance of these methods in predicting the true population sizes (2007 data). Our set-up was unique in that we knew the population sizes for turkey breeder farms (99) and meat turkey farms (592) in Canada in 2007, which we applied as our true population sizes, and had surveillance data from the Canadian Notifiable Avian Influenza Surveillance System (2008-2012). We defined each calendar year of sampling as a data source. We confirmed that the two-source capture-recapture methods were sensitive to the violation of the local independence assumption. The log-linear modeling and sample coverage approaches yielded estimates that were closer to the true population sizes than were the estimates provided by the two-source methods for both populations. The performance of both multi-source capture-recapture methods depended on the number of data sources analyzed and the size of the population. Simulation studies are recommended to better understand the limits of each multi-source capture-recapture method. PMID:25542525

  16. Design and development of a prototypical software for semi-automatic generation of test methodologies and security checklists for IT vulnerability assessment in small- and medium-sized enterprises (SME)

    NASA Astrophysics Data System (ADS)

    Möller, Thomas; Bellin, Knut; Creutzburg, Reiner

    2015-03-01

    The aim of this paper is to show the recent progress in the design and prototypical development of a software suite Copra Breeder* for semi-automatic generation of test methodologies and security checklists for IT vulnerability assessment in small and medium-sized enterprises.

  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. 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

  19. 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...

  20. Dendritic Target Region-Specific Formation of Synapses Between Excitatory Layer 4 Neurons and Layer 6 Pyramidal Cells.

    PubMed

    Qi, Guanxiao; Feldmeyer, Dirk

    2016-04-01

    Excitatory connections between neocortical layer 4 (L4) and L6 are part of the corticothalamic feedback microcircuitry. Here we studied the intracortical element of this feedback loop, the L4 spiny neuron-to-L6 pyramidal cell connection. We found that the distribution of synapses onto both putative corticothalamic (CT) and corticocortical (CC) L6 pyramidal cells (PCs) depends on the presynaptic L4 neuron type but is independent of the postsynaptic L6 PC type. L4 spiny stellate cells establish synapses on distal apical tuft dendrites of L6 PCs and elicit slow unitary excitatory postsynaptic potentials (uEPSPs) in L6 somata. In contrast, the majority of L4 star pyramidal neurons target basal and proximal apical oblique dendrites of L6 PCs and show fast uEPSPs. Compartmental modeling suggests that the slow uEPSP time course is primarily the result of dendritic filtering. This suggests that the dendritic target specificity of the 2 L4 spiny neuron types is due to their different axonal projection patterns across cortical layers. The preferential dendritic targeting by different L4 neuron types may facilitate the generation of dendritic Ca(2+) or Na(+) action potentials in L6 PCs; this could play a role in synaptic gain modulation in the corticothalamic pathway. PMID:25595180

  1. 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. PMID:26104263

  2. [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

  3. 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

  4. 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

  5. Association between intention to stay on the job and job satisfaction among Japanese nurses in small and medium-sized private hospitals.

    PubMed

    Kudo, Yasushi; Satoh, Toshihiko; Hosoi, Kaori; Miki, Takeo; Watanabe, Mitsuyasu; Kido, Shigeri; Aizawa, Yoshiharu

    2006-11-01

    In order to examine the relationship between the intention to stay on the job and job satisfaction among Japanese nurses, and to obtain clues for preventing turnover, we conducted a questionnaire survey. The subjects involved in the survey included 625 female nurses (registered nurses, licensed practical nurses and assistant nurses) working in 4 small and medium-sized private hospitals, excluding directors of nursing. Of the 625 questionnaires distributed, 556 (89.0%) were returned. After excluding the questionnaires with missing values, 480 questionnaires were analyzed (effective response rate, 76.8%). The average age of the respondents was 32.8 yr (range: 20-65). The content of the questionnaire was nurse attributes, job satisfaction (30 items) and intention to stay on the job. For job satisfaction, factor analysis (principal factor method and promax rotation) was performed, and factors with an eigenvalue of > or =1 were extracted. Six factors were extracted by factor analysis. These factors were interpreted as "Work as specialists" (1st factor), "Relationship with superiors" (2nd factor), "Comfortable life" (3rd factor), "Relationship among nurses" (4th factor), "Communication with physicians" (5th factor) and "Working conditions" (6th factor). The factor scores were calculated and used as a scale for the evaluation of job satisfaction. To investigate the factors associated with intention to stay on the job among nurses, the standard partial regression coefficient was computed by multiple linear regression analysis, with intention to stay on the job as the dependent variable, and nurse attributes and job satisfaction (factor scores) as independent variables. Various factors including the organizational culture of each hospital may affect the relationship between job satisfaction and the intention to stay on the job. In order to adjust for these factors, differences among hospitals were included in the statistical model as independent variables. The result of the

  6. Reaction-subdiffusion front propagation in a comblike model of spiny dendrites.

    PubMed

    Iomin, A; Méndez, V

    2013-07-01

    Fractional reaction-diffusion equations are derived by exploiting the geometrical similarities between a comb structure and a spiny dendrite. In the framework of the obtained equations, two scenarios of reaction transport in spiny dendrites are explored, where both a linear reaction in spines and nonlinear Fisher-Kolmogorov-Petrovskii-Piskunov reactions along dendrites are considered. In the framework of fractional subdiffusive comb model, we develop a Hamilton-Jacobi approach to estimate the overall velocity of the reaction front propagation. One of the main effects observed is the failure of the front propagation for both scenarios due to either the reaction inside the spines or the interaction of the reaction with the spines. In the first case the spines are the source of reactions, while in the latter case, the spines are a source of a damping mechanism. PMID:23944491

  7. 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.

  8. Synchronous behavior of two coupled electronic neurons

    NASA Astrophysics Data System (ADS)

    Pinto, R. D.; Varona, P.; Volkovskii, A. R.; Szücs, 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.

  9. 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

  10. 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). PMID:22195038

  11. Conservation and variation in the feeding mechanism of the spiny dogfish squalus acanthias

    PubMed

    Wilga; Motta

    1998-05-01

    Changes in the feeding mechanism with feeding behavior were investigated using high-speed video and electromyography to examine the kinematics and motor pattern of prey capture, manipulation and transport in the spiny dogfish Squalus acanthias (Squalidae: Squaliformes). In this study, Squalus acanthias used both suction and ram behaviors to capture and manipulate prey, while only suction was used to transport prey. The basic kinematic feeding sequence observed in other aquatic-feeding lower vertebrates is conserved in the spiny dogfish. Prey capture, bite manipulation and suction transport events are characterized by a common pattern of head movements and motor activity, but are distinguishable by differences in duration and relative timing. In general, capture events are longer in duration than manipulation and transport events, as found in other aquatic-feeding lower vertebrates. Numerous individual effects were found, indicating that individual sharks are capable of varying head movements and motor activity among successful feeding events. Upper jaw protrusion in the spiny dogfish is not restricted by its orbitostylic jaw suspension; rather, the upper jaw is protruded by 30 % of its head length, considerably more than in the lemon shark Negaprion brevirostris (Carcharhinidae: Carcharhiniformes) (18 %) with its hyostylic jaw suspension. One function of upper jaw protrusion is to assist in jaw closure by protruding the upper jaw as well as elevating the lower jaw to close the gape, thus decreasing the time to jaw closure. The mechanism of upper jaw protrusion was found to differ between squaliform and carcharhiniform sharks. Whereas the levator palatoquadrati muscle assists in retracting the upper jaw in the spiny dogfish, it assists in protruding the upper jaw in the lemon shark. This study represents the first comprehensive electromyographic and kinematic analysis of the feeding mechanism in a squaliform shark. PMID:9547315

  12. 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

    2015-01-01

    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. PMID:26782557

  13. 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.

  14. 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

  15. Secretagogin-containing neurons in the mouse main olfactory bulb.

    PubMed

    Kosaka, Katsuko; Kosaka, Toshio

    2013-01-01

    Secretagogin (SCGN) is a recently discovered calcium binding protein of the EF hand family. We studied the structural features of SCGN-positive neurons in the mouse main olfactory bulb (MOB). SCGN-positive neurons were localized throughout layers but clustered in the glomerular layer (GL), mitral cell layer (MCL) and granule cell layer (GCL). They were heterogeneous, including numerous juxtaglomerular neurons, granule cells, small to medium-sized neurons in the external plexiform layer (EPL), and a few small cells in the ependymal/subependymal layer. Calretinin and/or tyrosine hydroxylase occasionally colocalized in SCGN-positive juxtaglomerular neurons. Calretinin also frequently colocalized in SCGN-positive EPL and GCL neurons. Morphologically some of juxtaglomerular SCGN-positive neurons were classical periglomerular cells, whereas others were apparently different from those periglomerular cells, although they were further heterogeneous. Some extended one slender process into a glomerulus which passed the glomerulus and further penetrated into another nearby glomeruli, and thus their dendritic processes spanned two or three or more glomeruli. We named this type of juxtaglomerular neurons "transglomerular cells." With the stereological analysis we estimated total number of juxtaglomerular SCGN-positive neurons at about 80,000/single MOB. The present study revealed the diversity of SCGN-positive neurons in the mouse MOB and their particular structural properties hitherto unknown. PMID:24008127

  16. Report on the meetings of the small and medium size reactor (SMR) expert group of the organization for economic cooperation and development (OECD), Paris, France, June 15-16, 1989: Foreign trip report

    SciTech Connect

    Rowan, W.J.

    1989-07-05

    The traveler attended the meeting of the Small and Medium Size Reactor (SMR) Expert Group of the OECD. The group agreed to identify the potential for SMRs in OECD countries and to document their views in a report. The group also developed and initiated a plan and schedule for this effort. This report describes significant activities that took place during the meeting and presents relevant information that has been collected in recent international studies.

  17. Cooperative Photo-/Lewis Acid Catalyzed Tandem Intramolecular [3 + 2] Cross-Cycloadditions of Cyclopropane 1,1-Diesters with α,β-Unsaturated Carbonyls for Medium-Sized Carbocycles.

    PubMed

    Wang, Zhenjun; Chen, Shuai; Ren, Jun; Wang, Zhongwen

    2015-09-01

    A tandem isomerization/intramolecular [3 + 2] cross-cycloaddition (IMCC) of cyclopropane 1,1-diesters with α,β-unsaturated ketones/aldehydes under a cooperative catalysis of photo and Lewis acids has been successfully developed. This supplied a general and efficient strategy for construction of medium-sized carbocyclic (8-, 9-, and 10-membered) skeletons as well as such carbocycle-based bridged oxa-bicyclo[n.2.1] (n = 4-6) skeletons. PMID:26313742

  18. A Golgi deimpregnation study of neurons in the rhesus monkey visual cortex (areas 17 and 18).

    PubMed

    Werner, L; Winkelmann, E; Koglin, A; Neser, J; Rodewohl, H

    1989-01-01

    The morphological features of 298 neurons impregnated according to Golgi-Kopsch in areas 17 and 18 of Macaca mulatta were analyzed, and the same neurons were deimpregnated to visualize structural details of the somata in different types of neurons. The following cell types were investigated: Pyramidal and pyramid-like cells, spiny stellate cells, double bouquet cells, bipolar cells, chandelier cells, neurogliaform cells, basket and related cells. This procedure allows the evaluation of the nuclear-cytoplasmic proportion and the position of the nucleus besides shape and size of the cell body. Pyramidal and pyramid-like cells (N = 43), spiny stellate cells (N = 26), basket and related cells (N = 126) are variable in these features. A positive correlation between soma size and width of the cytoplasm is found in pyramidal, pyramid-like cells and spiny stellate cells. With the exception of some large somata in both these types of neurons the nucleus is found in a central position. Double bouquet cells (N = 6), bipolar cells (N = 13) and chandelier cells (N = 11) exhibit small cytoplasmic rims and centrally located nuclei. The small somata of neurogliaform cells (N = 37), however, and the small to very large somata of basket and related cells show broad cytoplasmic portions surrounding the eccentrically located nuclei. These findings allow the identification of different neuronal types in Nissl-stained sections on the basis of these soma features. This is a prerequisite for further detailed quantitative studies on the laminar distribution of different neuronal types in the visual cortex of the monkey. PMID:2610391

  19. SPARCL1-containing neurons in the human brainstem and sensory ganglion.

    PubMed

    Hashimoto, Naoya; Sato, Tadasu; Yajima, Takehiro; Fujita, Masatoshi; Sato, Ayumi; Shimizu, Yoshinaka; Shimada, Yusuke; Shoji, Noriaki; Sasano, Takashi; Ichikawa, Hiroyuki

    2016-06-01

    Secreted protein, acidic and rich in cysteine-like 1 (SPARCL1) is a member of the osteonectin family of proteins. In this study, immunohistochemistry for SPARCL1 was performed to obtain its distribution in the human brainstem, cervical spinal cord, and sensory ganglion. SPARCL1-immunoreactivity was detected in neuronal cell bodies including perikarya and proximal dendrites, and the neuropil. The motor nuclei of the IIIrd, Vth, VIth, VIIth, IXth, Xth, XIth, and XIIth cranial nerves and spinal nerves contained many SPARCL1-immunoreactive (-IR) neurons with medium-sized to large cell bodies. Small and medium-sized SPARCL1-IR neurons were distributed in sensory nuclei of the Vth, VIIth, VIIIth, IXth, and Xth cranial nerves. In the medulla oblongata, the dorsal column nuclei also had small to medium-sized SPARCL1-IR neurons. In addition, SPARCL1-IR neurons were detected in the nucleus of the trapezoid body and pontine nucleus within the pons and the arcuate nucleus in the medulla oblongata. In the cervical spinal cord, the ventral horn contained some SPARCL1-IR neurons with large cell bodies. These findings suggest that SPARCL1-containing neurons function to relay and regulate motor and sensory signals in the human brainstem. In the dorsal root (DRG) and trigeminal ganglia (TG), primary sensory neurons contained SPARCL1-immunoreactivity. The proportion of SPARCL1-IR neurons in the TG (mean ± SD, 39.9 ± 2.4%) was higher than in the DRG (30.6 ± 2.1%). SPARCL1-IR neurons were mostly medium-sized to large (mean ± SD, 1494.5 ± 708.3 μm(2); range, 320.4-4353.4 μm(2)) in the DRG, whereas such neurons were of various cell body sizes in the TG (mean ± SD, 1291.2 ± 532.8 μm(2); range, 209.3-4326.4 μm(2)). There appears to be a SPARCL1-containing sensory pathway in the ganglion and brainstem of the spinal and trigeminal nervous systems. PMID:27357901

  20. 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.

  1. Effect of magnetic pulses on Caribbean spiny lobsters: implications for magnetoreception.

    PubMed

    Ernst, David A; Lohmann, Kenneth J

    2016-06-15

    The Caribbean spiny lobster, Panulirus argus, is a migratory crustacean that uses Earth's magnetic field as a navigational cue, but how these lobsters detect magnetic fields is not known. Magnetic material thought to be magnetite has previously been detected in spiny lobsters, but its role in magnetoreception, if any, remains unclear. As a first step toward investigating whether lobsters might have magnetite-based magnetoreceptors, we subjected lobsters to strong, pulsed magnetic fields capable of reversing the magnetic dipole moment of biogenic magnetite crystals. Lobsters were subjected to a single pulse directed from posterior to anterior and either: (1) parallel to the horizontal component of the geomagnetic field (i.e. toward magnetic north); or (2) antiparallel to the horizontal field (i.e. toward magnetic south). An additional control group was handled but not subjected to a magnetic pulse. After treatment, each lobster was tethered in a water-filled arena located within 200 m of the capture location and allowed to walk in any direction. Control lobsters walked in seemingly random directions and were not significantly oriented as a group. In contrast, the two groups exposed to pulsed fields were significantly oriented in approximately opposite directions. Lobsters subjected to a magnetic pulse applied parallel to the geomagnetic horizontal component walked westward; those subjected to a pulse directed antiparallel to the geomagnetic horizontal component oriented approximately northeast. The finding that a magnetic pulse alters subsequent orientation behavior is consistent with the hypothesis that magnetoreception in spiny lobsters is based at least partly on magnetite-based magnetoreceptors. PMID:27045095

  2. 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. PMID:21459195

  3. Dendritic morphology of neurons in medial prefrontal cortex, hippocampus, and nucleus accumbens in adult SH rats.

    PubMed

    Sánchez, Fremioth; Gómez-Villalobos, María de Jesús; Juarez, Ismael; Quevedo, Lucía; Flores, Gonzalo

    2011-03-01

    We have studied, in spontaneously hypertensive (SH) rats at different ages (2, 4, and 8 months old), the dendritic morphological changes of the pyramidal neurons of the medial prefrontal cortex (mPFC) and hippocampus and medium spiny neurons of the nucleus accumbens (NAcc) induced by the chronic effect of high-blood pressure. As control animals, we used Wistar-Kioto (WK) rats. Blood pressure was measured every 2 months to confirm the increase in arterial blood pressure. Spontaneous locomotor activity was assessed, and then brains were removed to study the dendritic morphology by the Golgi-Cox stain method followed by Sholl analysis. SH animals at 4 and 8 months of age showed decreased spine density in pyramidal neurons from the mPFC and in medium spiny cells from the NAcc. At 8 months of age as well the pyramidal neurons from the hippocampus exhibited a reduction in the number of dendritic spines. An increase in locomotion in a novel environment at all ages in the SH rats was observed. Our results indicate that high-blood pressure alters the neuronal dendrite morphology of the mPFC, hippocampus, and NAcc. The increased locomotion behavior supports the idea that dopaminergic transmission is altered in the SH rats. This could enhance our understanding of the consequences of chronic high-blood pressure on brain structure, which may implicate cognitive impairment in hypertensive patients. PMID:20665725

  4. 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

  5. Neuronal polarization.

    PubMed

    Takano, Tetsuya; Xu, Chundi; Funahashi, Yasuhiro; Namba, Takashi; Kaibuchi, Kozo

    2015-06-15

    Neurons are highly polarized cells with structurally and functionally distinct processes called axons and dendrites. This polarization underlies the directional flow of information in the central nervous system, so the establishment and maintenance of neuronal polarization is crucial for correct development and function. Great progress in our understanding of how neurons establish their polarity has been made through the use of cultured hippocampal neurons, while recent technological advances have enabled in vivo analysis of axon specification and elongation. This short review and accompanying poster highlight recent advances in this fascinating field, with an emphasis on the signaling mechanisms underlying axon and dendrite specification in vitro and in vivo. PMID:26081570

  6. 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

  7. Seasonal thermogenic acclimation of diurnally and nocturnally active desert spiny mice.

    PubMed

    Kronfeld-Schor, N; Haim, A; Dayan, T; Zisapel, N; Klingenspor, M; Heldmaier, G

    2000-01-01

    Diurnally active golden spiny mice (Acomys russatus) and nocturnal common spiny mice (Acomys cahirinus) coexist in hot rocky deserts of Israel. Diurnal and nocturnal activities expose these species to different climatic conditions. Nonshivering thermogenesis (NST) capacity of individuals of both species immediately upon removal from the field exhibited seasonal changes, with no significant interspecific difference. Colony-reared mice of either species transferred in the laboratory from long to short photoperiod increased NST capacity, though to a lesser extent than observed in the seasonal acclimatization. The underlying biochemical mechanisms of short photoperiod acclimation differed between the species. In both Cytochrome-c oxidase (Cox) activity was higher in short as compared to long photoperiod. In short-photoperiod-acclimated A. cahirinus uncoupling protein (UCP) content in brown adipose tissue (BAT) was significantly higher than in long photoperiod, while in A. russatus there was no significant change. In A. russatus there was a significant increase in lipoprotein lipase (LPL) activity in BAT in short-photoperiod-acclimated individuals, while in A. cahirinus LPL activity was high under both acclimations. The low LPL activity in brown adipose tissue of desert-adapted A. russatus may facilitate lipid uptake in white adipose tissue, an advantage in desert conditions where food is scarce and irregularly distributed in space and time. PMID:10685905

  8. 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]. PMID:26455299

  9. 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. PMID:25230484

  10. 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

    2015-01-01

    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

  11. Inducers of settlement and moulting in post-larval spiny lobster.

    PubMed

    Stanley, Jenni A; Hesse, Jan; Hinojosa, Iván A; Jeffs, Andrew G

    2015-07-01

    The rapid and often remote location of suitable habitats used by migrating organisms is often critical to their subsequent recruitment, fitness and survival, and this includes in the marine environment. However, for the non-feeding post-larval stage of spiny lobsters, effective settlement cues for habitat selection are critical to their success but are poorly described. Therefore, the current study examined whether acoustic and substrate cues have the potential to shorten the time to moulting and affect their subsequent nutritional condition in the pueruli of the southern spiny lobster, Jasus edwardsii. Individuals moulted to first instar juveniles up to 38% faster when exposed to the underwater sound from two types of typical settlement habitat (coastal kelp- and urchin-dominated reefs) compared to those with no underwater sound. The settlement delay in the post-larvae without underwater sound also resulted in juveniles in poorer survival and nutritional condition as measured by their protein and lipid contents. In a separate experiment, post-larvae presented with seaweed and rock substrates were found to complete settlement and moult to juvenile by as much as 20% faster compared to those on the sand and control treatments. Overall, the results are the first to demonstrate that the pueruli of J. edwardsii have the ability to detect and respond to underwater sound, as well as determining that both acoustic and substrate cues play a role in modulating physiological development during settlement. PMID:25682060

  12. 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

  13. Pathogenicity and infection cycle of Vibrio owensii in larviculture of the ornate spiny lobster (Panulirus ornatus).

    PubMed

    Goulden, Evan F; Hall, Michael R; Bourne, David G; Pereg, Lily L; Høj, Lone

    2012-04-01

    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

  14. Chronic reparative changes in medium-sized vessels in a case of primary cutaneous anaplastic large-cell lymphoma with angioinvasive features and cytotoxic phenotype: new histopathological findings in line with indolent clinical behavior.

    PubMed

    Macarenco, Ricardo S; de Oliveira, Deilson Elgui

    2015-05-01

    Angioinvasion/angiodestruction has been reported in a small subset of primary cutaneous anaplastic large-cell lymphomas (PCALCL). Recently, PCALCL with angioinvasive features and cytotoxic phenotype has been characterized as a variant associated with good clinical outcomes despite worrisome histopathologic features. We report a case of PCALCL with angioinvasive features and cytotoxic phenotype associated with reparative changes on the wall of medium-sized vessels involved by the neoplasm, including intimal fibroblastic proliferation and luminal obliteration. This vascular pattern, although previously unreported in PCALCL, is in accordance with the indolent behavior observed in this entity and provides a further link with lymphomatoid papulosis type E. PMID:25365499

  15. 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) and Total Allowable Level of Landings (TAL). 648.231 Section 648.231 Wildlife and Fisheries FISHERY CONSERVATION AND MANAGEMENT, NATIONAL OCEANIC AND ATMOSPHERIC ADMINISTRATION, DEPARTMENT OF COMMERCE FISHERIES OF THE NORTHEASTERN UNITED...

  16. 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

    ...) and Total Allowable Level of Landings (TAL). 648.231 Section 648.231 Wildlife and Fisheries FISHERY CONSERVATION AND MANAGEMENT, NATIONAL OCEANIC AND ATMOSPHERIC ADMINISTRATION, DEPARTMENT OF COMMERCE FISHERIES... dogfish Annual Catch Target (ACT) and Total Allowable Level of Landings (TAL). (a) The Spiny...

  17. 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

    ...) and Total Allowable Level of Landings (TAL). 648.231 Section 648.231 Wildlife and Fisheries FISHERY CONSERVATION AND MANAGEMENT, NATIONAL OCEANIC AND ATMOSPHERIC ADMINISTRATION, DEPARTMENT OF COMMERCE FISHERIES... dogfish Annual Catch Target (ACT) and Total Allowable Level of Landings (TAL). (a) The Spiny...

  18. 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... Associated Plants and Invertebrates for the U.S. Caribbean for review, approval, and implementation by NMFS... and coral and reef associated plants and invertebrates species. The 2011 Caribbean ACL Amendment...

  19. Baculovirus infection of the armyworm (Lepidoptera:Noctuidae) feeding on spiny- or smooth-edged grass (Festuca spp.) leaf blades

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Susceptibility of the armyworm, Mythimna unipuncta (Haworth), to infection by a baculovirus isolated from a Kentucky armyworm population was compared on two suspected progenitors of tall fescue, Festuca mairei and Festuca arundinacea subsp. fenas, with spiny leaf margins intact or removed to test wh...

  20. 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).

  1. 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

    ... Amendment 10 and requested public comment (76 FR 54227). On September 23, 2011, NMFS published a proposed rule for Amendment 10 and requested public comment (76 FR 59102). The proposed rule and Amendment 10... Caribbean, Gulf of Mexico, and South Atlantic; Spiny Lobster Fishery of the Gulf of Mexico and...

  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

    ... the best available scientific information and reflect recent increases in spiny dogfish biomass. The... most recent catch and biomass estimates from the 2012 spring trawl survey. Updated estimates indicate that the female spawning stock biomass (SSB) for 2012 was 475.634 million lb (215,744 mt), about...

  3. Cytoarchitecture and Ultrastructure of Neural Stem Cell Niches and Neurogenic Complexes Maintaining Adult Neurogenesis in the Olfactory Midbrain of Spiny Lobsters, Panulirus argus

    PubMed Central

    Schmidt, Manfred; Derby, Charles D.

    2013-01-01

    New interneurons are continuously generated in small proliferation zones within neuronal somata clusters in the olfactory deutocerebrum of adult decapod crustaceans. Each proliferation zone is connected to a clump of cells containing one neural stem cell (i.e., adult neuroblast), thus forming a “neurogenic complex.” Here we provide a detailed analysis of the cytoarchitecture of neurogenic complexes in adult spiny lobsters, Panulirus argus, based on transmission electron microscopy and labeling with cell-type-selective markers. The clump of cells is composed of unique bipolar clump-forming cells that collectively completely envelop the adult neuroblast and are themselves ensheathed by a layer of processes of multipolar cell body glia. An arteriole is attached to the clump of cells, but dye perfusion experiments show that hemolymph has no access to the interior of the clump of cells. Thus, the clump of cells fulfills morphological criteria of a protective stem cell niche, with clump-forming cells constituting the adult neuroblast’s microenvironment together with the cell body glia processes separating it from other tissue components. Bromodeoxyuridine pulse-chase experiments with short survival times suggest that adult neuroblasts are not quiescent but rather cycle actively during daytime. We propose a cell lineage model in which an asymmetrically dividing adult neuroblast repopulates the pool of neuronal progenitor cells in the associated proliferation zone. In conclusion, as in mammalian brains, adult neurogenesis in crustacean brains is fueled by neural stem cells that are maintained by stem cell niches that preserve elements of the embryonic microenvironment and contain glial and vascular elements. PMID:21523781

  4. Neuronal arithmetic

    PubMed Central

    Silver, R. Angus

    2016-01-01

    The vast computational power of the brain has traditionally been viewed as arising from the complex connectivity of neural networks, in which an individual neuron acts as a simple linear summation and thresholding device. However, recent studies show that individual neurons utilize a wealth of nonlinear mechanisms to transform synaptic input into output firing. These mechanisms can arise from synaptic plasticity, synaptic noise, and somatic and dendritic conductances. This tool kit of nonlinear mechanisms confers considerable computational power on both morphologically simple and more complex neurons, enabling them to perform a range of arithmetic operations on signals encoded in a variety of different ways. PMID:20531421

  5. Isolation and characterization of eight polymorphic microsatellites for the spotted spiny lobster, Panulirus guttatus.

    PubMed

    Truelove, Nathan; Behringer, Donald C; Butler Iv, Mark J; Preziosi, Richard F

    2016-01-01

    Microsatellite sequences were isolated from enriched genomic libraries of the spotted spiny lobster, Panulirus guttatus using 454 pyrosequencing. Twenty-nine previously developed polymerase chain reaction primer pairs of Panulirus argus microsatellite loci were also tested for cross-species amplification in Panulirus guttatus. In total, eight consistently amplifying, and polymorphic loci were characterized for 57 individuals collected in the Florida Keys and Bermuda. The number of alleles per locus ranged from 8 to 20 and observed heterozygosities ranged from 0.409 to 0.958. Significant deviations from Hardy-Weinberg equilibrium were found in one locus from Florida and three loci from Bermuda. Quality control testing indicated that all loci were easy to score, highly polymorphic and showed no evidence of linkage disequilibrium. Null alleles were detected in three loci with moderate frequencies ranging from (20% to 22%). These eight microsatellites provide novel molecular markers for future conservation genetics research of P. guttatus. PMID:26855853

  6. 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.

  7. 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

  8. Seasonal feeding ecology of ring-tailed lemurs: a comparison of spiny and gallery forest habitats.

    PubMed

    LaFleur, Marni; Sauther, Michelle L

    2015-01-01

    Although Lemur catta persists in many habitat types in southern Madagascar, its ecology has been primarily studied within gallery forests. We compare plant food selection and properties for ring-tailed lemurs in the spiny and gallery forests over the synchronized lactation period (September to March) that includes both the dry and wet seasons. We found no significant habitat-specific differences in the type of plant part consumed per month (i.e. flower, fruit, leaf) or between the intake of soluble carbohydrates. However, the presence and use of Tamarindus indica plants appear to elevate protein and fiber intake in the gallery forest lemurs' diets. Protein is especially important for reproductive females who incur the added metabolic costs associated with lactation; however, fiber can disrupt protein digestion. Future work should continue to investigate how variations of protein and fiber affect ring-tailed lemur dietary choice and nutrient acquisition. PMID:26022298

  9. Isolation and characterization of eight polymorphic microsatellites for the spotted spiny lobster, Panulirus guttatus

    PubMed Central

    Behringer, Donald C.; Butler IV, Mark J.; Preziosi, Richard F.

    2016-01-01

    Microsatellite sequences were isolated from enriched genomic libraries of the spotted spiny lobster, Panulirus guttatus using 454 pyrosequencing. Twenty-nine previously developed polymerase chain reaction primer pairs of Panulirus argus microsatellite loci were also tested for cross-species amplification in Panulirus guttatus. In total, eight consistently amplifying, and polymorphic loci were characterized for 57 individuals collected in the Florida Keys and Bermuda. The number of alleles per locus ranged from 8 to 20 and observed heterozygosities ranged from 0.409 to 0.958. Significant deviations from Hardy–Weinberg equilibrium were found in one locus from Florida and three loci from Bermuda. Quality control testing indicated that all loci were easy to score, highly polymorphic and showed no evidence of linkage disequilibrium. Null alleles were detected in three loci with moderate frequencies ranging from (20% to 22%). These eight microsatellites provide novel molecular markers for future conservation genetics research of P. guttatus. PMID:26855853

  10. 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

    2010-09-01

    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. PMID:21387989

  11. 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. PMID:25048683

  12. 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

  13. 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. PMID:23063001

  14. 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. PMID:22872494

  15. 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.

  16. Sublethal effect of copper toxicity against histopathological changes in the spiny lobster, Panulirus homarus (Linnaeus, 1758).

    PubMed

    Maharajan, A; Rajalakshmi, S; Vijayakumaran, M; Kumarasamy, P

    2012-02-01

    The tissue damage induced by various organic pollutants in aquatic animals is well documented, but there is a dearth of information relating to the histological alterations induced by copper in the spiny lobster. In the present study, intermoult juveniles of the spiny lobster Panulirus homarus (average weight 150-200 g) were exposed to two sublethal concentrations of the copper (9.55 and 19.1 μg/l) for a period of 28 days. The muscle, hepatopancreas, midgut, gills, thoracic ganglion and heart of the lobsters were then dissected out and processed for light microscopic studies. Exposure to copper was found to result in several alterations in the histoarchitecture of the muscle, hepatopancreas, midgut, gills, thoracic ganglion and heart of P. homarus. The alterations included disruption and congestion of muscle bundle in muscle tissue; blackened haemocytes; distended lumen and F cell; necrosis of the tubules of the hepatopancreas; disarrangement of circular muscle of the midgut; accumulation of haemocytes in the haemocoelic space; swelling and fusion of lamellae; abnormal gill tips; hyperplastic, necrotic, and blackened secondary gill lamellae of the gills; damaged neurosecretory cell and sensory and motor fibre; necrotic of the thoracic ganglion; dispersedly arranged muscle bands; clumped satellite cells and nucleus of the heart. The results obtained suggest that the muscle, hepatopancreas, midgut, gills, thoracic ganglion and heart of lobsters exposed to copper were structurally altered. Such alterations could affect vital physiological functions, such as absorption, storage and secretion of the hepatopancreas, digestion of gut and respiration, osmotic and ionic regulations of the gills, which in turn could ultimately affect the survival and growth of P. homarus. Thus, all possible remedial measures should be adopted to prevent the occurrence of copper contamination in the aquatic environment. PMID:21861131

  17. 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

  18. Phenotypical characterization of the rat striatal neurons expressing the D1 dopamine receptor gene.

    PubMed Central

    Le Moine, C; Normand, E; Bloch, B

    1991-01-01

    In situ hybridization experiments were performed in rat brain sections from normal and 6-hydroxydopamine-treated rats in order to map and identify the neurons expressing the D1 receptor gene in the striatum and the substantia nigra. Procedures of combined in situ hybridization, allowing the simultaneous detection of two mRNAs in the same section or in adjacent sections, were used to characterize the phenotypes of the neurons expressing the D1 receptor gene. D1 receptor mRNA was found in neurons all over the caudate-putamen, the accumbens nucleus, and the olfactory tubercle but not in the substantia nigra. In the caudate-putamen and accumbens nucleus, most of the neurons containing D1 receptor mRNA were characterized as medium-sized substance P neurons and distinct from those containing D2 receptor mRNA. Nevertheless, 15-20% of the substance P neurons did not contain D1 receptor mRNA. The neurons containing preproenkephalin A mRNA did not contain D1 receptor mRNA but contained D2 receptor mRNA. A small number of cholinergic and somatostatinergic neurons exhibited a weak reaction for D1 receptor mRNA. These results demonstrate that dopamine acts on efferent striatal neurons through expression of distinct receptors--namely, D1 and D2 in separate cell populations (substance P and preproenkephalin A neurons, respectively)--and can also act on nonprojecting neurons through D1 receptor expression. Images PMID:1827915

  19. Topographical distribution and morphology of NADPH-diaphorase-stained neurons in the human claustrum

    PubMed Central

    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. PMID:24904317

  20. Hippocampal neuronal subtypes develop abnormal dendritic arbors in the presence of Fragile X astrocytes.

    PubMed

    Jacobs, S; Cheng, C; Doering, L C

    2016-06-01

    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 21days. 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 21days in culture. The results further dictate the critical role astrocytes play in governing neuronal morphology including altered dendrite development in Fragile X. PMID:26968765

  1. Enhanced Excitability of Primary Sensory Neurons and Altered Gene Expression of Neuronal Ion Channels in Dorsal Root Ganglion in Paclitaxel-Induced Peripheral Neuropathy

    PubMed Central

    Zhang, Haijun; Dougherty, Patrick M.

    2014-01-01

    Background The mechanism of chemotherapy-induced peripheral neuropathy after paclitaxel treatment is not well understood. Given the poor penetration of paclitaxel into central nervous system, peripheral nervous system is most at risk. Methods Intrinsic membrane properties of dorsal root ganglion (DRG) neurons were studied by intracellular recordings. Multiple-gene real-time Polymerase Chain Reaction array was used to investigate gene expression of DRG neuronal ion channels. Results Paclitaxel increased the incidence of spontaneous activity from 4.8% to 27.1% in large and from 0% to 33.3% in medium-sized neurons. Paclitaxel decreased the rheobase (nA) from 1.6 ± 0.1 to 0.8 ± 0.1 in large, from 1.5 ± 0.2 to 0.6 ± 0.1 in medium-sized, and from 1.6 ± 0.2 to 1.0 ± 0.1 in small neurons. After paclitaxel, other characteristics of membrane properties in each group remained the same except that Aδ neurons showed shorter action potential fall time (ms) (1.0 ± 0.2, n = 10 vs. 1.8 ± 0.3, n = 9, paclitaxel vs. vehicle). Meanwhile, real-time polymerase chain reaction array revealed an alteration in expression of some neuronal ion channel genes including upregulation of HCN1 (fold change 1.76 ± 0.06) and Nav1.7 (1.26 ± 0.02) and downregulation of Kir channels (Kir1.1, 0.73 ± 0.05, Kir3.4, 0.66 ± 0.06) in paclitaxel-treated animals. Conclusions The increased neuronal excitability and the changes in gene expression of some neuronal ion channels in DRG may provide insight into the molecular and cellular basis of paclitaxel neuropathy, which may lead to novel therapeutic strategies. PMID:24534904

  2. 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

  3. Expression of programmed death-1 in primary cutaneous CD4-positive small/medium-sized pleomorphic T-cell lymphoma, cutaneous pseudo-T-cell lymphoma, and other types of cutaneous T-cell lymphoma.

    PubMed

    Cetinözman, Fatma; Jansen, Patty M; Willemze, Rein

    2012-01-01

    In this study we investigated whether programmed death-1 (PD-1) could serve as a useful diagnostic marker to differentiate between primary cutaneous CD4 small/medium-sized pleomorphic T-cell lymphoma (PCSM-TCL) and cutaneous pseudo-T-cell lymphomas on the one hand and other types of cutaneous T-cell lymphomas (CTCLs) on the other. Formalin-fixed, paraffin-embedded skin biopsies from 26 patients with PCSM-TCL or pseudo-T-cell lymphoma, including 1 patient with a lymphomatoid drug eruption, and 52 skin biopsies from other types of CTCLs were stained for PD-1. In addition, PD-1-positive cases were stained with antibodies against BCL6, CXCL13, and CD10 to determine a possible relationship with follicular helper T (TFH) cells. In all 26 cases of PCSM-TCL or pseudo-T-cell lymphoma, the medium-sized to large-sized atypical T cells consistently expressed PD-1, BCL6, and CXCL13 but not CD10. PD-1 expression was found in only 2 of 21 cases of mycosis fungoides and in only 2 of 16 cases of cutaneous peripheral T-cell lymphoma, unspecified. All 4 patients with an aggressive epidermotropic cytotoxic CD8 CTCL and all 11 cases with a primary cutaneous CD30 lymphoproliferative disorder were negative for PD-1. In conclusion, PD-1 is typically expressed by atypical cells in PCSM-TCL and pseudo-T-cell lymphoma but is not expressed or is rarely expressed in other types of CTCLs. Therefore, it may serve as a suitable adjunct in differential diagnosis. Our results demonstrate that the atypical cells in PCSM-TCL and pseudo-T-cell lymphomas share a common TFH phenotype and support the view that most cases classified nowadays as PCSM-TCL are identical to cutaneous pseudo-T-cell lymphomas described previously. PMID:21989349

  4. REST and CoREST Modulate Neuronal Subtype Specification, Maturation and Maintenance

    PubMed Central

    Gokhan, Solen; Zheng, Deyou; Bergman, Aviv; Mehler, Mark F.

    2009-01-01

    Background The repressor element-1 silencing transcription factor/neuron-restrictive silencer factor (REST/NRSF) is a master regulator of neuronal gene expression. REST functions as a modular scaffold for dynamic recruitment of epigenetic regulatory factors including its primary cofactor, the corepressor for element-1-silencing transcription factor (CoREST), to genomic loci that contain the repressor element-1 (RE1) binding motif. While REST was initially believed to silence RE1 containing neuronal genes in neural stem cells (NSCs) and non-neuronal cells, emerging evidence shows an increasingly complex cell type- and developmental stage-specific repertoire of REST target genes and functions that include regulation of neuronal lineage maturation and plasticity. Methodology/Principal Findings In this study, we utilized chromatin immunoprecipitation on chip (ChIP-chip) analysis to examine REST and CoREST functions during NSC-mediated specification of cholinergic neurons (CHOLNs), GABAergic neurons (GABANs), glutamatergic neurons (GLUTNs), and medium spiny projection neurons (MSNs). We identified largely distinct but overlapping profiles of REST and CoREST target genes during neuronal subtype specification including a disproportionately high percentage that are exclusive to each neuronal subtype. Conclusions/Significance Our findings demonstrate that the differential deployment of REST and CoREST is an important regulatory mechanism that mediates neuronal subtype specification by modulating specific gene networks responsible for inducing and maintaining neuronal subtype identity. Our observations also implicate a broad array of factors in the generation of neuronal diversity including but not limited to those that mediate homeostasis, cell cycle dynamics, cell viability, stress responses and epigenetic regulation. PMID:19997604

  5. Passive and active membrane properties contribute to the temporal filtering properties of midbrain neurons in vivo.

    PubMed

    Fortune, E S; Rose, G J

    1997-05-15

    This study examined the contributions of passive and active membrane properties to the temporal selectivities of electrosensory neurons in vivo. The intracellular responses to time-varying (2-30 Hz) electrosensory stimulation and current injection of 27 neurons in the midbrain of the weakly electric fish Eigenmannia were recorded. Each neuron was filled with biocytin to reveal its anatomy. Neurons were divided into two biophysically distinct groups based on their frequency-dependent responses to sinusoidal current injection over the range 2-30 Hz. Fourteen neurons showed low-pass filtering, with a maximum decline in the amplitude of voltage responses of >2.6 dB (X = 4.30 dB, s = 1.10 dB) to sinusoidal current injection. These neurons also showed low-pass filtering of electrosensory information but with larger maximum declines in postsynaptic potential amplitude (X = 9.53 dB, s = 3.34 dB; n = 10). These neurons had broad dendritic arbors and relatively spiny dendrites. Five neurons showed all-pass filtering, having maximum decline in the amplitude of voltage responses of <2.0 dB (X = 1.16 dB, s = 0.61 dB). For electrosensory stimuli, however, these neurons showed low-, band-, or high-pass filtering. These neurons had small dendritic arbors and few or no spines. Voltage-dependent "active" conductances were revealed in eight neurons by using several levels of current clamp. In four of these neurons, the duration of the voltage-dependent conductances decreased in concert with the period of the electrosensory stimulus, whereas in the other four neurons the duration of the voltage-dependent conductances was relatively short (<30 msec) and nearly constant across sensory stimulation frequencies. These conductances enhanced the temporal filtering properties of neurons. PMID:9133400

  6. 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.

  7. 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

  8. Characterising the fate of nitrogenous waste from the sea-cage aquaculture of spiny lobsters using numerical modelling.

    PubMed

    Lee, Soxi; Hartstein, Neil D; Jeffs, Andrew

    2015-06-01

    Although the aquaculture of spiny lobsters has been expanding since the 1970s, very little is known about the potential environmental impacts on water quality of this activity. This study quantified the production of dissolved inorganic nitrogen (DIN) from Australasian red spiny lobsters, Jasus edwardsii, in the laboratory, and these data were then used in a numerical model to predict the dispersal pattern of DIN from a hypothetical commercial spiny lobster farm for a coastal site where such a farm would typically be located. Modelling scenarios were set up with combinations of two different stocking densities (3 and 5 kg m(-3)), two different diets (mussels and moist artificial diet) and three different feed conversion ratios (FCR = 3, 5 and 28). DIN excretion rate from unfed lobsters in the laboratory on average was 1.10 ± 0.12 μg N g(-1) h(-1) while feeding lobsters on mussels and artificial diet increased DIN excretion significantly by around eightfold and twofold, respectively. Ammonia was consistently the dominant contributor to measured DIN output from lobsters. Modelling results indicated that the mean elevated DIN from a hypothetical farm where the lobsters were fed with mussels ranged from 7 up to 20 μg N L(-1) with increasing stocking density and FCR and was 30-150 % higher than the mean elevated DIN resulting from lobsters fed with artificial diet. Overall, the results indicated that DIN output from the hypothetical spiny lobster sea-cage farming is unlikely to be problematic using the FCR, stocking density, and the number of cages modelled at the coastal site in this study. Furthermore, feeding lobsters with artificial diet can help maintain a lower DIN output than seafood, such as mussels or trash fish. PMID:25601612

  9. Comparative kinematics of the forelimb during swimming in red-eared slider (Trachemys scripta) and spiny softshell (Apalone spinifera) turtles.

    PubMed

    Pace, C M; Blob, R W; Westneat, M W

    2001-10-01

    Softshell turtles (Family Trionychidae) possess extensive webbing between the digits of the manus, suggesting that the forelimb may serve as an effective thrust generator during aquatic locomotion. However, the hindlimb has previously been viewed as the dominant propulsive organ in swimming freshwater turtles. To evaluate the potential role of the forelimb in thrust production during swimming in freshwater turtles, we compared the forelimb morphology and three-dimensional forelimb kinematics of a highly aquatic trionychid turtle, the spiny softshell Apalone spinifera, and a morphologically generalized emydid turtle, the red-eared slider Trachemys scripta. Spiny softshells possess nearly twice as much forelimb surface area as sliders for generating drag-based thrust. In addition, although both species use drag-based propulsion, several aspects of forelimb kinematics differ significantly between these species. During the thrust phase of the forelimb cycle, spiny softshells hold the elbow and wrist joints significantly straighter than sliders, thereby further increasing the surface area of the limb that can move water posteriorly and increasing the velocity of the distal portion of the forelimb. These aspects of swimming kinematics in softshells should increase forelimb thrust production and suggest that the forelimbs make more substantial contributions to forward thrust in softshell turtles than in sliders. Spiny softshells also restrict forelimb movements to a much narrower dorsoventral and anteroposterior range than sliders throughout the stroke, thereby helping to minimize limb movements potentially extraneous to forward thrust production. These comparisons demonstrate considerable diversity in the forelimb kinematics of turtles that swim using rowing motions of the limbs and suggest that the evolution of turtle forelimb mechanics produced a variety of contrasting solutions for aquatic specialization. PMID:11606600

  10. 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

  11. Expression profile of vesicular nucleotide transporter (VNUT, SLC17A9) in subpopulations of rat dorsal root ganglion neurons.

    PubMed

    Nishida, Kentaro; Nomura, Yuka; Kawamori, Kanako; Moriyama, Yoshinori; Nagasawa, Kazuki

    2014-09-01

    ATP plays an important role in the signal transduction between sensory neurons and satellite cells in dorsal root ganglia (DRGs). In primary cultured DRG neurons, ATP is known to be stored in lysosomes via a vesicular nucleotide transporter (VNUT), and to be released into the intercellular space through exocytosis. DRGs consist of large-, medium- and small-sized neurons, which play different roles in sensory transmission, but there is no information on the expression profiles of VNUT in DRG subpopulations. Here, we obtained detailed expression profiles of VNUT in isolated rat DRG tissues. On immunohistochemical analysis, VNUT was found in DRG neurons, and was predominantly expressed by the small- and medium-sized DRG ones, as judged upon visual inspection, and this was compatible with the finding that the number of VNUT-positive DRG neurons in IB4-positive cells was greater than that in NF200-positive ones. These results suggest that VNUT play a role in ATP accumulation in DRG neurons, especially in small- and medium-sized ones, and might be involved in ATP-mediated nociceptive signaling in DRGs. PMID:25043192

  12. 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

  13. Motor Neuron Diseases

    MedlinePlus

    ... Enhancing Diversity Find People About NINDS NINDS Motor Neuron Diseases Information Page Condensed from Motor Neuron Diseases ... and Information Publicaciones en Español What are Motor Neuron Diseases? The motor neuron diseases (MNDs) are a ...

  14. Motor Neuron Diseases

    MedlinePlus

    ... called upper motor neurons ) are transmitted to nerve cells in the brain stem and spinal cord (called lower motor neurons ) and from them to particular muscles. Upper motor neurons direct the lower motor neurons ...

  15. PPAR-δ is repressed in Huntington's disease, is required for normal neuronal function and can be targeted therapeutically.

    PubMed

    Dickey, Audrey S; Pineda, Victor V; Tsunemi, Taiji; Liu, Patrick P; Miranda, Helen C; Gilmore-Hall, Stephen K; Lomas, Nicole; Sampat, Kunal R; Buttgereit, Anne; Torres, Mark-Joseph Manalang; Flores, April L; Arreola, Martin; Arbez, Nicolas; Akimov, Sergey S; Gaasterland, Terry; Lazarowski, Eduardo R; Ross, Christopher A; Yeo, Gene W; Sopher, Bryce L; Magnuson, Gavin K; Pinkerton, Anthony B; Masliah, Eliezer; La Spada, Albert R

    2016-01-01

    Huntington's disease (HD) is a progressive neurodegenerative disorder caused by a CAG trinucleotide repeat expansion in the huntingtin (HTT) gene, which encodes a polyglutamine tract in the HTT protein. We found that peroxisome proliferator-activated receptor delta (PPAR-δ) interacts with HTT and that mutant HTT represses PPAR-δ-mediated transactivation. Increased PPAR-δ transactivation ameliorated mitochondrial dysfunction and improved cell survival of neurons from mouse models of HD. Expression of dominant-negative PPAR-δ in the central nervous system of mice was sufficient to induce motor dysfunction, neurodegeneration, mitochondrial abnormalities and transcriptional alterations that recapitulated HD-like phenotypes. Expression of dominant-negative PPAR-δ specifically in the striatum of medium spiny neurons in mice yielded HD-like motor phenotypes, accompanied by striatal neuron loss. In mouse models of HD, pharmacologic activation of PPAR-δ using the agonist KD3010 improved motor function, reduced neurodegeneration and increased survival. PPAR-δ activation also reduced HTT-induced neurotoxicity in vitro and in medium spiny-like neurons generated from stem cells derived from individuals with HD, indicating that PPAR-δ activation may be beneficial in HD and related disorders. PMID:26642438

  16. 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. PMID:18843093

  17. Multiple copies of SRY on the large Y chromosome of the Okinawa spiny rat, Tokudaia muenninki.

    PubMed

    Murata, Chie; Yamada, Fumio; Kawauchi, Norihiro; Matsuda, Yoichi; Kuroiwa, Asato

    2010-09-01

    The Okinawa spiny rat, Tokudaia muenninki, is the only species with a Y chromosome in the genus Tokudaia. Its phylogenic relationship with two XO/XO species, Tokudaia osimensis and Tokudaia tokunoshimensis, lacking a Y chromosome and the mammalian sex-determining gene SRY, is unknown. Furthermore, there has been little cytogenetic analysis of the sex chromosomes in T. muenninki. Therefore, we constructed molecular phylogenetic trees with nucleotide sequences of cyt b, RAG1, and IRBP. All trees strongly supported that T. muenninki was the first to diverge from the Tokudaia ancestor, indicating that loss of the Y chromosome and SRY occurred in the common ancestor of the two XO/XO species after T. muenninki diverged. We found that the X and Y chromosomes of T. muenninki consisted of large euchromatic and heterochromatic regions by conducting G- and C-banding analyses. PCR, Southern blotting, and FISH revealed that T. muenninki males had multiple SRY copies on the long arm of the Y chromosome. At least three of 24 SRY sequences contained a complete open reading frame (ORF). A species-specific substitution from alanine to serine was found in all copies at the DNA-binding surface within the HMG-box, suggesting that it occurred in an original SRY. PMID:20574822

  18. Evolutionary divergence of geographic subspecies within the scalloped spiny lobster Panulirus homarus (Linnaeus 1758).

    PubMed

    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

  19. 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. PMID:25698893

  20. Seasonal dynamics of the cestode fauna in spiny dogfish, Squalus acanthias (Squaliformes: Squalidae).

    PubMed

    Pickering, Maria; Caira, Janine N

    2014-06-01

    This study furthers understanding of cestode infections in a marine environment through time and space by following seasonal fluctuations in infection parameters of three cestode species (Gilquinia squali, Trilocularia gracilis and Phyllobothrium squali) parasitizing spiny dogfish (Squalus acanthias) in the northwest Atlantic and comparing them to work previously published from the northeast Atlantic on T. gracilis. For each cestode species, host size, season and presence of the other cestode species were analysed using generalized linear models to determine if they were good predictors of prevalence and intensity. Infection parameters differed across season for the three cestode species. However, within T. gracilis seasonal trends were found to be remarkably similar on both sides of the Atlantic, differing only in a somewhat delayed decline in prevalence in the northwest Atlantic. The differences seen in infection measures across cestode species likely reflect the unique life history strategies of different parasite species. While general trends appear to be maintained across disparate localities, variation seen is likely due to differences in accessibility to intermediate hosts and host diet across sites. The knowledge gained from understanding cestode infections in the vast ocean environment allows us to speculate about the factors driving fluctuations in parasite infections in elasmobranchs. PMID:24569058

  1. 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. PMID:15123215

  2. 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. PMID:23858462

  3. 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. PMID:25877639

  4. A GABA-activated chloride-conductance not blocked by picrotoxin on spiny lobster neuromuscular preparations.

    PubMed Central

    Albert, J.; Lingle, C. J.; Marder, E.; O'Neil, M. B.

    1986-01-01

    Conductance increases to gamma-aminobutyric acid (GABA) were recorded in the gm6b and opener muscle of the spiny lobsters, Panulirus interruptus and P. argus. GABA-evoked responses were insensitive to picrotoxin at concentrations as high as 5 X 10(-5) M. Some blockade by picrotoxin was observed at higher concentrations. In normal physiological saline, the reversal potential of the Panulirus GABA-induced response was near the resting potential. The reversal potential was unaffected by reductions in sodium and calcium. Reduction of chloride by 50% resulted in a greater than 10 mV shift in the reversal potential of the GABA-induced response. Muscimol was able to mimic the action of GABA while baclofen was without effect. Bicuculline was a weak blocker. Avermectin B1a irreversibly increased the chloride permeability of the gm6b membrane. This conductance increase was blocked by picrotoxin over a range of concentrations similar to those required for blockade of the GABA-induced response. GABA-induced responses of the gm6b muscle of Homarus americanus were blocked almost completely by picrotoxin 10(-6) M. Sensitivity to picrotoxin is not invariably associated with GABA-activated chloride-mediated conductance increases. It is suggested that alteration in the binding-site for picrotoxin on the GABA-activated chloride-ion channel does not change other functional characteristics of the GABA-induced response. PMID:3708210

  5. 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. PMID:27226467

  6. 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

  7. 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

  8. Comparative analysis of methods for determining bite force in the spiny dogfish Squalus acanthias.

    PubMed

    Huber, Daniel Robert; Motta, Philip Jay

    2004-01-01

    Many studies have identified relationships between the forces generated by the cranial musculature during feeding and cranial design. Particularly important to understanding the diversity of cranial form amongst vertebrates is knowledge of the generated magnitudes of bite force because of its use as a measure of ecological performance. In order to determine an accurate morphological proxy for bite force in elasmobranchs, theoretical force generation by the quadratomandibularis muscle of the spiny dogfish Squalus acanthias was modeled using a variety of morphological techniques, and lever-ratio analyses were used to determine resultant bite forces. These measures were compared to in vivo bite force measurements obtained with a pressure transducer during tetanic stimulation experiments of the quadratomandibularis. Although no differences were found between the theoretical and in vivo bite forces measured, modeling analyses indicate that the quadratomandibularis muscle should be divided into its constituent divisions and digital images of the cross-sections of these divisions should be used to estimate cross-sectional area when calculating theoretical force production. From all analyses the maximum bite force measured was 19.57 N. This relatively low magnitude of bite force is discussed with respect to the ecomorphology of the feeding mechanism of S. acanthias to demonstrate the interdependence of morphology, ecology, and behavior in organismal design. PMID:14695686

  9. 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. PMID:26358988

  10. 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

  11. 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. PMID:21183442

  12. 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. PMID:23757129

  13. 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. PMID:24047891

  14. Reproductive and population parameters of spiny dogfish Squalus acanthias in the south-western Atlantic Ocean.

    PubMed

    Colonello, J H; Cortés, F; Belleggia, M; Massa, A M

    2016-05-01

    The objective of this study was to estimate reproductive and population parameters of the spiny dogfish Squalus acanthias for the south-western Atlantic Ocean. In total, 2714 specimens (1616 males and 1098 females) were collected from surveys carried out using research vessels. Males ranged from 225 to 861 mm total length (LT ) and females from 235 to 925 mm LT . The size at maturity of females (651 mm) was significantly greater than that of males (565 mm). The maximum proportion of mature individuals (Pmax ) of the gestation ogive was <1, which indicates that a proportion of mature females was not in gestation. This inactivity may be explained by the occurrence of resting periods between cycles or by the asynchrony of the reproductive cycle. The estimated Pmax for the maternity ogive suggested that about one third of mature females were in the maternity stage (i.e. with embryos >156 mm). The temporal and spatial co-occurrence of non-gravid adult females at different stages of ovarian development, as well as gravid females at all embryonic development stages would indicate that the female reproductive cycle in the south-western Atlantic Ocean is asynchronous. The results indicate that S. acanthias is susceptible to fishing pressure on account of its length at maturity, extended reproductive cycles and low fecundity. PMID:27020803

  15. Studies on the reproductive biology of spiny eel, Macrognathus aral from upper Assam.

    PubMed

    Abujam, Santoshkumar Singh; Biswas, S P

    2011-09-01

    The one-stripe spiny eel, Macrognathus aral (Bloch and Schneider), has been gaining importance not only as a food fish but also as an aquarium fish for its body shape and behaviour. The overall M:F ratio recorded 1:0.27, both the males and females were mostly mature in May-August. The peak values of gonado somatic ratio (GSR) attained during May for males (1.3) and August forfemales (12.4) indicating that the fish have only one breeding season during summer. The range of ova diameter was found to vary from 0.3 to 1.4 mm, the absolute fecundity ranged from 250 (21.6 cm/27.4 g) to 5220.1 (27.2 cm/66.3 g) while relative fecundity ranged from 9.1 to 128.9. The 50% maturity is attained in length group of 10.1-14 cm for males and 14.1-18 cm for females. The species is a moderately fecund, isochronal spawner and having a restricted breeding season. The relationship between fecundity and body weight and length has also been discussed. PMID:22319881

  16. 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

  17. 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. PMID:11800038

  18. 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

  19. 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

  20. Synaptic Conductance Estimates of the Connection Between Local Inhibitor Interneurons and Pyramidal Neurons in Layer 2/3 of a Cortical Column.

    PubMed

    Hoffmann, Jochen H O; Meyer, H S; Schmitt, Arno C; Straehle, Jakob; Weitbrecht, Trinh; Sakmann, Bert; Helmstaedter, Moritz

    2015-11-01

    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

  1. 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

    2014-10-01

    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. PMID:25130619

  2. 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. PMID:23271344

  3. 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. PMID:17855583

  4. Cannabinoid receptor 1-expressing neurons in the nucleus accumbens.

    PubMed

    Winters, Bradley D; Krüger, Juliane M; Huang, Xiaojie; Gallaher, Zachary R; Ishikawa, Masago; Czaja, Krzysztof; Krueger, James M; Huang, Yanhua H; Schlüter, Oliver M; Dong, Yan

    2012-10-01

    Endocannabinoid signaling critically regulates emotional and motivational states via activation of cannabinoid receptor 1 (CB1) in the brain. The nucleus accumbens (NAc) functions to gate emotional and motivational responses. Although expression of CB1 in the NAc is low, manipulation of CB1 signaling within the NAc triggers robust emotional/motivational alterations related to drug addiction and other psychiatric disorders, and these effects cannot be exclusively attributed to CB1 located at afferents to the NAc. Rather, CB1-expressing neurons in the NAc, although sparse, appear to be critical for emotional and motivational responses. However, the cellular properties of these neurons remain largely unknown. Here, we generated a knock-in mouse line in which CB1-expressing neurons expressed the fluorescent protein td-Tomato (tdT). Using these mice, we demonstrated that tdT-positive neurons within the NAc were exclusively fast-spiking interneurons (FSIs). These FSIs were electrically coupled with each other, and thus may help synchronize populations/ensembles of NAc neurons. CB1-expressing FSIs also form GABAergic synapses on adjacent medium spiny neurons (MSNs), providing feed-forward inhibition of NAc output. Furthermore, the membrane excitability of tdT-positive FSIs in the NAc was up-regulated after withdrawal from cocaine exposure, an effect that might increase FSI-to-MSN inhibition. Taken together with our previous findings that the membrane excitability of NAc MSNs is decreased during cocaine withdrawal, the present findings suggest that the basal functional output of the NAc is inhibited during cocaine withdrawal by multiple mechanisms. As such, CB1-expressing FSIs are targeted by cocaine exposure to influence the overall functional output of the NAc. PMID:23012412

  5. Prostaglandin D2 modulates calcium signals induced by prostaglandin E2 in neurons of rat dorsal root ganglia.

    PubMed

    Ott, Daniela; Simm, Björn; Pollatzek, Eric; Gerstberger, Rüdiger; Rummel, Christoph; Roth, Joachim

    2015-06-15

    Fever in response to a localized subcutaneous stimulation with a low dose of lipopolysaccharide (LPS) can be attenuated by co-administration of a local anesthetic or the non-selective cyclooxygenase (COX) inhibitor diclofenac at doses, which do not exert systemic effects when injected at sites remote from the area of inflammatory stimulation. These results suggest a participation of neuronal afferent signals mediated by COX-products in the manifestation of fever under these conditions. We therefore, measured intracellular Ca(2+)-concentrations in cultured neurons from rat dorsal root ganglia (DRG) stimulated with the pyrogenic mediator prostaglandin E2 (PGE2), the anti-inflammatory and antipyretic mediator PGD2, mixtures of both PGs, and menthol using the fura-2 ratio imaging technique. Neurons could be grouped according to their size with diameters of about 15μm (small), 35μm (medium sized), or 55μm (large). 96 out of 264 neurons responded to PGE2 with pronounced Ca(2+)-signals, 53 of them being also responsive to menthol, indicative of their function as cold-sensors. 80% of these neurons belonged to the medium sized group. In a next experiment, we tested whether Ca(2+)-signals of PGE2 responsive neurons were modulated by PGD2. In 60% of all neurons investigated (n=57), the strength of the PGE2-induced Ca(2+)-signals was reduced by co-administration of PGD2. This effect was also observed in those neurons that were responsive to PGE2 and menthol (n=23; p<0.001). This observation indicates antagonistic effects of PGE2 and PGD2 on a neuronal pathway that involves cold sensors and is activated during a localized subcutaneous inflammation. This finding might provide an explanation for the reported antipyretic and anti-inflammatory capacities of PGD2. PMID:25912777

  6. Two waves of anisotropic growth generate enlarged follicles in the spiny mouse

    PubMed Central

    2014-01-01

    Background Mammals exhibit a remarkable variety of phenotypes and comparative studies using novel model species are needed to uncover the evolutionary developmental mechanisms generating this diversity. Here, we undertake a developmental biology and numerical modeling approach to investigate the development of skin appendages in the spiny mouse, Acomys dimidiatus. Results We demonstrate that Acomys spines, possibly involved in display and protection, are enlarged awl hairs with a concave morphology. The Acomys spines originate from enlarged placodes that are characterized by a rapid downwards growth which results in voluminous follicles. The dermal condensation (dermal papilla) at the core of the follicle is very large and exhibits a curved geometry. Given its off-centered position, the dermal papilla generates two waves of anisotropic proliferation, first of the posterior matrix, then of the anterior inner root sheath (IRS). Higher in the follicle, the posterior and anterior cortex cross-section areas substantially decrease due to cortex cell elongation and accumulation of keratin intermediate filaments. Milder keratinization in the medulla gives rise to a foamy material that eventually collapses under the combined compression of the anterior IRS and elongation of the cortex cells. Simulations, using linear elasticity theory and the finite-element method, indicate that these processes are sufficient to replicate the time evolution of the Acomys spine layers and the final shape of the emerging spine shaft. Conclusions Our analyses reveal how hair follicle morphogenesis has been altered during the evolution of the Acomys lineage, resulting in a shift from ancestral awl follicles to enlarged asymmetrical spines. This study contributes to a better understanding of the evolutionary developmental mechanisms that generated the great diversity of skin appendage phenotypes observed in mammals. PMID:25705371

  7. Decadal variability in growth of the Caribbean spiny lobster Panulirus argus (Decapoda: Paniluridae) in Cuban waters.

    PubMed

    de León, Maria Estela; Martínez, Juana López; Cota, Daniel Lluch; Vázquez, Sergio Hernández; Rafael, Puga

    2005-01-01

    Annual von Bertalanffy growth parameters of the Caribbean spiny lobster (Panulirus argus) in Cuban waters were estimated from a long term study (40 years) by length-based methods ELEFAN and the new version of SLCA. Data of around 800 000 lobsters (with carapace length ranging 14 to 199mm) were randomly sampled in artificial shelters (a non selective fishing gear very common in the lobster fishery), through the field monitory program established for this species since 1963 in 14 localities of southwestern Cuban shelf. The software ELEFAN showed problems to converge in an optimal combination of the instantaneous growth coefficient (K) and the asymptotic length (Linfinity) of the von Bertalanffy equation, whereas the new SLCA software produced value estimates of K between 0.20 and 0.27 year(-1) and values of Linfinity between 177 and 190 mm carapace length, all within the range reported in the literature. The standardized anomalies of both parameters showed the presence of cycles along the analyzed time series. Decadal variability in growth parameters was revealed through the spectral analysis indicating cycles of 16 and 20 years for K and of 16 years for Linfinity. The incidence of some factors such as biomass and temperature that modulate growth in this crustacean was explored, using a nonlinear multiple regression model. These combined factors explained 33% and 69% of the variability of K and Linfinity respectively. The growth coefficient appeared to be maximum with annual mean sea surface temperature of 28. 1 degrees C and the largest Linfinity is reached at a annual men biomass level of 23,000 t. These results should be the basis to understand the Cuban lobster population dynamics. PMID:17354457

  8. 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. PMID:27370801

  9. Panulirus argus virus 1 detected in oceanic postlarvae of Caribbean spiny lobster: implications for disease dispersal.

    PubMed

    Lozano-Álvarez, Enrique; Briones-Fourzán, Patricia; Huchin-Mian, Juan Pablo; Segura-García, Iris; Ek-Huchim, Juan Pablo; Améndola-Pimenta, Mónica; Rodríguez-Canul, Rossanna

    2015-12-01

    Panulirus argus virus 1 (PaV1), a pathogenic virus that specifically attacks Caribbean spiny lobsters Panulirus argus, was recently detected in newly settled postlarvae of P. argus. As PaV1 appears not to be vertically transmitted, infected postlarvae likely acquire PaV1 from the water, but whether this can occur in oceanic waters where the planktonic larvae (phyllosomata) metamorphose into nektonic postlarvae remains unknown. Late-stage phyllosomata and postlarvae of P. argus were collected at distances of 2 to 100 km from the Caribbean coast of Mexico in 2 oceanographic cruises. Most postlarvae were caught in the upper meter of water, usually along with masses of floating Sargassum algae. A PaV1-PCR assay was used to test 169 phyllosomata (stages VI-X) and 239 postlarvae. All phyllosomata tested negative, but 2 postlarvae, 1 from each cruise, tested positive for PaV1. These postlarvae were collected at 55 and 48 km offshore over depths of 850 and 1800 m, respectively, suggesting that postlarvae can acquire PaV1 in offshore waters. We hypothesize that floating Sargassum may be an environmental reservoir for PaV1. The PaV1 allele (460 pb) found in an infected postlarva was more closely related to PaV1 alleles found in lobsters from Puerto Rico than in lobsters from any other location (including Mexico), suggesting high gene flow and long-distance dispersal of PaV1, consistent with previous studies of high genetic connectivity across the Caribbean. PMID:26648108

  10. Histology and ultrastructure of male reproductive system of the Indian Spiny lobster Panulirus homarus (Decapoda: Palinuridae).

    PubMed

    Pillai, S Lakshmi; Nasser, M; Sanil, N K

    2014-06-01

    The spiny lobster Panulirus homarus, distributed along the Southeast and Southwest coasts of India, is an important commercial species having mariculture potential. Despite its importance, the structural and ultrastructure features of male gonads from this species have received scarce attention. Hence this study was aimed to describe the male reproductive tract of the species, using standard histological and electron microscopy techniques. Gonads from 94 specimens of P. homarus ranging in carapace length 37mm-92mm from Vizhinjam (Southwest coast of India.) were obtained and processed for the study (Histology-70 numbers & ultrastructure-24 numbers). The male reproductive system consists of paired testis and vas deferens located in the cephalo-thoracic region. Macroscopically, the reproductive tract was observed in lobsters > 35mm carapace length. In immature testis, spermatogonia were seen which measured 6.9-13.8 microm in diameter and in the mature testis primary (5.4-5.9 microm) and secondary spermatocytes (2.8-3 microm) and spermatids (2.2-2.4 microm) were present. Each vas deferens consists of proximal and distal portions. The spermatophoric mass begins formation in the proximal vas deferens. In the distal vas deferens the spermatophoric mass containing the spermatozoa are arranged in packets towards the periphery by the gelatinous matrix produced by the typhlosole. Ultrastructurally, the spermatogonia have lamina, nucleus and mitochondria like bodies, the primary spermatocytes have nucleus, dense chromatin and vacuolated cytoplasm and the spermatids have mitochondria, endoplasmic reticulum and centrioles. The endoplasmic reticulum and the nuclear envelope in the spermatids form the acrosome. The radial arms with microtubules are formed in association with the dense endoplasmic reticulum, near the nucleus. The sperm has a spherical structure with the nucleus, lamellar region, spikes and acrosome. This is the first comprehensive report of the structure of the

  11. Propagation of CaMKII translocation waves in heterogeneous spiny dendrites.

    PubMed

    Bressloff, Paul C

    2013-06-01

    CaMKII (Ca²⁺-calmodulin-dependent protein kinase II) is a key regulator of glutamatergic synapses and plays an essential role in many forms of synaptic plasticity. It has recently been observed experimentally that stimulating a local region of dendrite not only induces the local translocation of CaMKII from the dendritic shaft to synaptic targets within spines, but also initiates a wave of CaMKII translocation that spreads distally through the dendrite with an average speed of order 1 μm/s. We have previously developed a simple reaction-diffusion model of CaMKII translocation waves that can account for the observed wavespeed and predicts wave propagation failure if the density of spines is too high. A major simplification of our previous model was to treat the distribution of spines as spatially uniform. However, there are at least two sources of heterogeneity in the spine distribution that occur on two different spatial scales. First, spines are discrete entities that are joined to a dendritic branch via a thin spine neck of submicron radius, resulting in spatial variations in spine density at the micron level. The second source of heterogeneity occurs on a much longer length scale and reflects the experimental observation that there is a slow proximal to distal variation in the density of spines. In this paper, we analyze how both sources of heterogeneity modulate the speed of CaMKII translocation waves along a spiny dendrite. We adapt methods from the study of the spread of biological invasions in heterogeneous environments, including homogenization theory of pulsating fronts and Hamilton-Jacobi dynamics of sharp interfaces. PMID:22588358

  12. Examining urea flux across the intestine of the spiny dogfish, Squalus acanthias.

    PubMed

    Gary Anderson, W; McCabe, Chris; Brandt, Catherine; Wood, Chris M

    2015-03-01

    Recent examination of urea flux in the intestine of the spiny dogfish shark, Squalus acanthias, has shown that feeding significantly enhances urea uptake across the intestine, and this was significantly inhibited following mucosal addition of phloretin. The present study examined potential mechanisms of urea uptake across the dogfish intestine in starved and fed dogfish. Unidirectional flux chambers were used to examine the kinetics of urea uptake, and to determine the influence of sodium, ouabain, competitive urea analogues, and phloretin on urea uptake across the gut of fed dogfish. Intestinal epithelial preparations from starved and fed dogfish were mounted in Ussing chambers to examine the effect of phloretin on bidirectional solute transport across the intestine. In the unidirectional studies, the maximum uptake rate of urea was found to be 35.3±6.9 μmol.cm(-2).h(-1) and Km was found to be 291.8±9.6 mM in fed fish, and there was a mild inhibition of urea uptake following mucosal addition of competitive agonists. Addition of phloretin, Na-free Ringers and ouabain to the mucosal side of intestinal epithelia also led to a significant reduction in urea uptake in fed fish. In the Ussing chamber studies there was a net influx of urea in fed fish and a small insignificant efflux in starved fish. Addition of phloretin blocked urea uptake in fed fish when added to the mucosal side. Furthermore, phloretin had no effect on ion transport across the intestinal epithelia with the exception of the divalent cations, magnesium and calcium. PMID:25479361

  13. Spiny Mice Modulate Eumelanin to Pheomelanin Ratio to Achieve Cryptic Coloration in “Evolution Canyon,” Israel

    PubMed Central

    Singaravelan, Natarajan; Pavlicek, Tomas; Beharav, Alex; Wakamatsu, Kazumasa; Ito, Shosuke; Nevo, Eviatar

    2010-01-01

    Background Coat coloration in mammals is an explicit adaptation through natural selection. Camouflaging with the environment is the foremost evolutionary drive in explaining overall coloration. Decades of enquiries on this topic have been limited to repetitive coat color measurements to correlate the morphs with background/habitat blending. This led to an overwhelming endorsement of concealing coloration as a local phenotypic adaptation in animals, primarily rodents to evade predators. However, most such studies overlooked how rodents actually achieve such cryptic coloration. Cryptic coloration could be attained only through optimization between the yellow- to brown-colored “pheomelanin” and gray to black-colored “eumelanin” in the hairs. However, no study has explored this conjecture yet. “Evolution Canyon” (EC) in Israel is a natural microscale laboratory where the relationship between organism and environment can be explored. EC is comprised of an “African” slope (AS), which exhibits a yellow-brownish background habitat, and a “European” slope (ES), exhibiting a dark grayish habitat; both slopes harbor spiny mice (Acomys cahirinus). Here, we examine how hair melanin content of spiny mice living in the opposing slopes of EC evolves toward blending with their respective background habitat. Methodology/Principal Findings We measured hair-melanin (both eumelanin and pheomelanin) contents of 30 spiny mice from the EC using high-performance liquid chromatography (HPLC) that detects specific degradation products of eumelanin and pheomelanin. The melanin pattern of A. cahirinus approximates the background color of the slope on which they dwell. Pheomelanin is slightly (insignificantly) higher in individuals found on the AS to match the brownish background, whereas individuals of the ES had significantly greater eumelanin content to mimic the dark grayish background. This is further substantiated by a significantly higher eumelanin and pheomelanin

  14. 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. PMID:26596534

  15. Immunohistochemical Localization of Guanylate Cyclase within Neurons of Rat Brain

    NASA Astrophysics Data System (ADS)

    Ariano, Marjorie A.; Lewicki, John A.; Brandwein, Harvey J.; Murad, Ferid

    1982-02-01

    The immunohistochemical localization of guanylate cyclase [GTP pyrophosphate-lyase (cyclizing), EC 4.6.1.2] has been examined in rat neocortex, caudate-putamen, and cerebellum by using specific monoclonal antibodies. Immunofluorescence could be seen within somata and proximal dendrites of neurons in these regions. A nuclear immunofluorescence reaction to guanylate cyclase was characteristically absent. The staining pattern for guanylate cyclase was coincident with previously described localizations of cyclic GMP immunofluorescence within medium spiny neurons of the caudate-putamen and pyramidal cells of the neocortex. Cerebellar guanylate cyclase immunoreactivity was primarily confined to Purkinje cells and their primary dendrites, similar to the pattern reported for cyclic GMP-dependent protein kinase localization. Guanylate cyclase immunofluorescence was abolished when the monoclonal antibodies were exposed to purified enzyme prior to incubation of the tissue slices or when control antibody was substituted for the primary antibody. Immunohistochemical localization of cyclic AMP in these same tissues was readily distinguished from that of guanylate cyclase or cyclic GMP, showing uniform fluorescence throughout the cell bodies of neurons and glial elements.

  16. Spontaneous Synaptic Activation of Muscarinic Receptors by Striatal Cholinergic Neuron Firing.

    PubMed

    Mamaligas, Aphroditi A; Ford, Christopher P

    2016-08-01

    Cholinergic interneurons (CHIs) play a major role in motor and learning functions of the striatum. As acetylcholine does not directly evoke postsynaptic events at most striatal synapses, it remains unclear how postsynaptic cholinergic receptors encode the firing patterns of CHIs in the striatum. To examine the dynamics of acetylcholine release, we used optogenetics and paired recordings from CHIs and medium spiny neurons (MSNs) virally overexpressing G-protein-activated inwardly rectifying potassium (GIRK) channels. Due to the efficient coupling between endogenous muscarinic receptors and GIRK channels, we found that firing of individual CHIs resulted in monosynaptic spontaneous inhibitory post-synaptic currents (IPSCs) in MSNs. Paired CHI-MSN recordings revealed that the high probability of acetylcholine release at these synapses allowed muscarinic receptors to faithfully encode physiological activity patterns from individual CHIs without failure. These results indicate that muscarinic receptors in striatal output neurons reliably decode CHI firing. PMID:27373830

  17. Number and Laminar Distribution of Neurons in a Thalamocortical Projection Column of Rat Vibrissal Cortex

    PubMed Central

    Wimmer, Verena C.; Oberlaender, M.; de Kock, Christiaan P.J.; Sakmann, Bert; Helmstaedter, Moritz

    2010-01-01

    This is the second article in a series of three studies that investigate the anatomical determinants of thalamocortical (TC) input to excitatory neurons in a cortical column of rat primary somatosensory cortex (S1). Here, we report the number and distribution of NeuN-positive neurons within the C2, D2, and D3 TC projection columns in P27 rat somatosensory barrel cortex based on an exhaustive identification of 89 834 somata in a 1.15 mm3 volume of cortex. A single column contained 19 109 ± 444 neurons (17 560 ± 399 when normalized to a standard-size projection column). Neuron density differences along the vertical column axis delineated “cytoarchitectonic” layers. The resulting neuron numbers per layer in the average column were 63 ± 10 (L1), 2039 ± 524 (L2), 3735 ± 905 (L3), 4447 ± 439 (L4), 1737 ± 251 (L5A), 2235 ± 99 (L5B), 3786 ± 168 (L6A), and 1066 ± 170 (L6B). These data were then used to derive the layer-specific action potential (AP) output of a projection column. The estimates confirmed previous reports suggesting that the ensembles of spiny L4 and thick-tufted pyramidal neurons emit the major fraction of APs of a column. The number of APs evoked in a column by a sensory stimulus (principal whisker deflection) was estimated as 4441 within 100 ms post-stimulus. PMID:20534784

  18. Explosive morphological diversification of spiny-finned teleost fishes in the aftermath of the end-Cretaceous extinction.

    PubMed

    Friedman, Matt

    2010-06-01

    The spiny-finned teleost fishes (Acanthomorpha) include nearly one-third of all living vertebrate species and assume a bewildering array of bodyplans, but the macroevolutionary assembly of modern acanthomorph biodiversity remains largely unexplored. Here, I reconstruct the trajectory of morphological diversification in this major radiation from its first appearance in the Late Cretaceous to the Miocene using a geometric morphometric database comprising more than 600 extinct species known from complete body fossils. The anatomical diversity (disparity) of acanthomorphs is low throughout the Cretaceous, increases sharply and significantly in the wake of the Cretaceous-Palaeogene (K-P) extinction, and shows little change throughout subsequent Cenozoic intervals. This pattern of morphological diversification appears robust to two potential biasing factors: the 'Lagerstätten effect', and the non-random segregation of rare and common taxa along phenotypic axes. Dissecting the trajectory of acanthomorph radiation along phylogenetic lines reveals that the abrupt post-extinction increase in disparity is driven largely by the proliferation of trophically diverse modern groups within Percomorpha, a spiny-fin subclade containing more than 15 000 living species and identified as showing a substantially elevated diversification rate relative to background vertebrate levels. A major component of the Palaeogene acanthomorph radiation reflects colonization of morphospace previously occupied by non-acanthomorph victims of the K-P. However, other aspects of morphological diversification cannot be explained by this simple ecological release model, suggesting that multiple factors contributed to the prolific anatomical radiation of acanthomorphs. PMID:20133356

  19. Molecular evidence for multiple phylogenetic groups within two species of invasive spiny whiteflies and their parasitoid wasp.

    PubMed

    Uesugi, R; Sato, Y; Han, B-Y; Huang, Z-D; Yara, K; Furuhashi, K

    2016-06-01

    The invasive orange spiny whitefly (OSW) Aleurocanthus spiniferus has extended its distribution to non-native areas since the early 20th century. In a similar manner, the invasive tea spiny whitefly (TSW) A. camelliae has been expanding over East Asia in recent decades. In this study, the genetic diversity of OSW and TSW and of their important parasitoid wasp Encarsia smithi was investigated in China and Japan to enable more efficient biological control policies. We detected two phylogenetic groups (haplogroups A1 and A2) in OSW and three phylogenetic groups (haplotypes B1 and B2, and haplogroup B3) in TSW in China; however, only a single haplotype was detected in each whitefly species in Japan. Based on historical records and molecular data, OSW was considered to be native to China whereas TSW has probably expanded to China from a more southern location in the last 50 years; China appears to be the source region for OSW and TSW invading Japan. In E. smithi, two phylogenetic groups were detected in Japan: haplotype I, associated with OSW, and haplogroup II mostly associated with TSW, except in two locations. These data support the hypothesis that E. smithi parasitizing TSW in Japan did not originate from the existent population parasitizing OSW but was newly imported into Japan following the invasion of its host. PMID:26782948

  20. Near-Infrared Spectroscopy as a Novel Non-Invasive Tool to Assess Spiny Lobster Nutritional Condition.

    PubMed

    Simon, Cedric J; Rodemann, Thomas; Carter, Chris G

    2016-01-01

    Rapid non-invasive monitoring of spiny lobster nutritional condition has considerable application in the established fishery, live market and prospective aquaculture. The aim of this research was to test the feasibility of near-infrared spectroscopy (NIRS) as a novel non-invasive tool to assess the nutritional condition of three lobster species. Lobster (n = 92) abdominal muscle dry matter (AMDM) and carbon content (AMC) correlated significantly with indices of nutritional condition including hepatopancreas dry matter (HPDM; rho = 0.83, 0.78), total lipid content (HPTL; rho = 0.85, 0.87) and haemolymph total protein (TP; rho = 0.89, 0.87 respectively). Abdominal muscle nitrogen content (AMN) was a poor correlate of nutritional condition. Models based on FT-NIR scanning of whole lobster tails successfully predicted AMDM, AMN and AMC (RMSECV = 1.41%, 0.35% and 0.91%; R2 = 0.75, 0.65, 0.77, respectively), and to a lower accuracy HPDM, HPTL and TP (RMSECV = 6.22%, 8.37%, 18.4 g l-1; R2 = 0.51, 0.70, 0.83, respectively). NIRS was applied successfully to assess the condition of spiny lobsters non-invasively. This pilot study paves the way for the development of crustacean condition models using portable non-invasive devices in the laboratory or in the field. PMID:27442242

  1. Near-Infrared Spectroscopy as a Novel Non-Invasive Tool to Assess Spiny Lobster Nutritional Condition

    PubMed Central

    Rodemann, Thomas; Carter, Chris G.

    2016-01-01

    Rapid non-invasive monitoring of spiny lobster nutritional condition has considerable application in the established fishery, live market and prospective aquaculture. The aim of this research was to test the feasibility of near-infrared spectroscopy (NIRS) as a novel non-invasive tool to assess the nutritional condition of three lobster species. Lobster (n = 92) abdominal muscle dry matter (AMDM) and carbon content (AMC) correlated significantly with indices of nutritional condition including hepatopancreas dry matter (HPDM; rho = 0.83, 0.78), total lipid content (HPTL; rho = 0.85, 0.87) and haemolymph total protein (TP; rho = 0.89, 0.87 respectively). Abdominal muscle nitrogen content (AMN) was a poor correlate of nutritional condition. Models based on FT-NIR scanning of whole lobster tails successfully predicted AMDM, AMN and AMC (RMSECV = 1.41%, 0.35% and 0.91%; R2 = 0.75, 0.65, 0.77, respectively), and to a lower accuracy HPDM, HPTL and TP (RMSECV = 6.22%, 8.37%, 18.4 g l-1; R2 = 0.51, 0.70, 0.83, respectively). NIRS was applied successfully to assess the condition of spiny lobsters non-invasively. This pilot study paves the way for the development of crustacean condition models using portable non-invasive devices in the laboratory or in the field. PMID:27442242

  2. Explosive morphological diversification of spiny-finned teleost fishes in the aftermath of the end-Cretaceous extinction

    PubMed Central

    Friedman, Matt

    2010-01-01

    The spiny-finned teleost fishes (Acanthomorpha) include nearly one-third of all living vertebrate species and assume a bewildering array of bodyplans, but the macroevolutionary assembly of modern acanthomorph biodiversity remains largely unexplored. Here, I reconstruct the trajectory of morphological diversification in this major radiation from its first appearance in the Late Cretaceous to the Miocene using a geometric morphometric database comprising more than 600 extinct species known from complete body fossils. The anatomical diversity (disparity) of acanthomorphs is low throughout the Cretaceous, increases sharply and significantly in the wake of the Cretaceous–Palaeogene (K–P) extinction, and shows little change throughout subsequent Cenozoic intervals. This pattern of morphological diversification appears robust to two potential biasing factors: the ‘Lagerstätten effect’, and the non-random segregation of rare and common taxa along phenotypic axes. Dissecting the trajectory of acanthomorph radiation along phylogenetic lines reveals that the abrupt post-extinction increase in disparity is driven largely by the proliferation of trophically diverse modern groups within Percomorpha, a spiny-fin subclade containing more than 15 000 living species and identified as showing a substantially elevated diversification rate relative to background vertebrate levels. A major component of the Palaeogene acanthomorph radiation reflects colonization of morphospace previously occupied by non-acanthomorph victims of the K–P. However, other aspects of morphological diversification cannot be explained by this simple ecological release model, suggesting that multiple factors contributed to the prolific anatomical radiation of acanthomorphs. PMID:20133356

  3. Cytoarchitecture of chicken Wulst: a Golgi study on cell types and their maturation after hatching.

    PubMed

    Tömböl, T; Maglóczky, Z

    1990-01-01

    In the Golgi preparation of visual Wulst of chicken four types of projection neurons were found: type 1a, 1b, 1c, and 1d neurons, which are distinguished on the basis of their dendritic ramification pattern and especially on the density of the dendritic spines. Type 1a has large dendritic tree with moderately dense spiny dendrites. Type 1b has very dense spiny dendrites. Type 1c is a small neuron with moderately dense spiny dendrites. Type 1d is a star-pyramid-like neuron with a short, bifurcating apical dendrite. The final dendritic pattern and spine density of projection neurons was found to develop at the end of the first month. In the Wulst short axon cells (interneurons-INs) of different types occur: large, medium-sized and small INs can be observed. Their axon-arborizations are significantly different from each other. Some of them are GABA-immuno-positive neurons, which are very probably inhibitory interneurons. Stellate-like neurons also occur in IHA and HIS. These neurons have sparsely spiny dendrites and locally arborizing axons. PMID:2089867

  4. Transitions between sleep and feeding states in rat ventral striatum neurons

    PubMed Central

    Tellez, Luis A.; Perez, Isaac O.; Simon, Sidney A.

    2012-01-01

    Neurons in the nucleus accumbens (NAc) have been shown to participate in several behavioral states, including feeding and sleep. However, it is not known if the same neuron participates in both states and, if so, how similar are the responses. In addition, since the NAc contains several cell types, it is not known if each type participates in the transitions associated with feeding and sleep. Such knowledge is important for understanding the interaction between two different neural networks. For these reasons we recorded ensembles of NAc neurons while individual rats volitionally transitioned between the following states: awake and goal directed, feeding, quiet-awake, and sleeping. We found that during both feeding and sleep states, the same neurons could increase their activity (be activated) or decrease their activity (be inactivated) by feeding and/or during sleep, thus indicating that the vast majority of NAc neurons integrate sleep and feeding signals arising from spatially distinct neural networks. In contrast, a smaller population was modulated by only one of the states. For the majority of neurons in either state, we found that when one population was excited, the other was inhibited, suggesting that they act as a local circuit. Classification of neurons into putative interneurons [fast-spiking interneurons (pFSI) and choline acetyltransferase interneurons (pChAT)] and projection medium spiny neurons (pMSN) showed that all three types are modulated by transitions to and from feeding and sleep states. These results show, for the first time, that in the NAc, those putative inhibitory interneurons respond similarly to pMSN projection neurons and demonstrate interactions between NAc networks involved in sleep and feeding. PMID:22745464

  5. Differential neuronal changes in medial prefrontal cortex, basolateral amygdala and nucleus accumbens after postweaning social isolation.

    PubMed

    Wang, Yu-Chun; Ho, Ue-Cheung; Ko, Meng-Ching; Liao, Chun-Chieh; Lee, Li-Jen

    2012-04-01

    The mesocorticolimbic system contains dopamine (DA)-producing neurons in the ventral tegmental area (VTA) and their projection targets, including the medial prefrontal cortex (mPFC), amygdala (AMY) and nucleus accumbens (NAc). Disruption of this system might attribute to mental illnesses. In the present study, we adopted the postweaning social isolation paradigm to model neuropsychiatric disorders and studied the functional and structural changes of the mesocorticolimbic system. After 8-9 weeks of isolation, rats exhibited hyperlocomotor activity and impaired sensorimotor gating compared to group-reared controls. However, the number of tyrosine hydroxylase-positive VTA neurons and the volume of VTA were not affected. Comparing with group-reared controls, the DA levels in the isolation-reared were not altered in the VTA, mPFC and NAc but decreased in the AMY. In the structural aspect, dendritic features of layer II/III pyramidal mPFC neurons; pyramidal neurons in the basolateral nucleus of amygdala (BLA) and medium spiny neurons in the core region of the NAc (NAcc) were examined. Interestingly, the neuronal changes were region-specific. The mPFC neurons had reduced dendritic complexity, spine density and elongated terminal branches. The BLA neurons had extensive dendritic arbors with short branches but unchanged spine density. The NAcc neurons had reduced total dendritic length but the segment length and spine density remained the same. Together, the results demonstrated the structural and functional changes in the mesocorticolimbic DA system of socially isolated rats. These changes may account for the behavioral impairments in these rats and attribute to the susceptibility to mental disorders related to schizophrenia and depression. PMID:22002740

  6. B cell receptor accessory molecule CD79α: characterisation and expression analysis in a cartilaginous fish, the spiny dogfish (Squalus acanthias).

    PubMed

    Li, Ronggai; Wang, Tiehui; Bird, Steve; Zou, Jun; Dooley, Helen; Secombes, Christopher J

    2013-06-01

    CD79α (also known as Igα) is a component of the B cell antigen receptor complex and plays an important role in B cell signalling. The CD79α protein is present on the surface of B cells throughout their life cycle, and is absent on all other healthy cells, making it a highly reliable marker for B cells in mammals. In this study the spiny dogfish (Squalus acanthias) CD79α (SaCD79α) is described and its expression studied under constitutive and stimulated conditions. The spiny dogfish CD79α cDNA contains an open reading frame of 618 bp, encoding a protein of 205 amino acids. Comparison of the SaCD79α gene with that of other species shows that the gross structure (number of exons, exon/intron boundaries, etc.) is highly conserved across phylogeny. Additionally, analysis of the 5' flanking region shows SaCD79α lacks a TATA box and possesses binding sites for multiple transcription factors implicated in its B cell-specific gene transcription in other species. Spiny dogfish CD79α is most highly expressed in immune tissues, such as spleen, epigonal and Leydig organ, and its transcript level significantly correlates with those of spiny dogfish immunoglobulin heavy chains. Additionally, CD79α transcription is up-regulated, to a small but significant degree, in peripheral blood cells following stimulation with pokeweed mitogen. These results strongly indicate that, as in mammals, spiny dogfish CD79α is expressed by shark B cells where it associates with surface-bound immunoglobulin to form a fully functional BCR, and thus may serve as a pan-B cell marker in future shark immunological studies. PMID:23454429

  7. An axosomatic and axodendritic multipolar neuron in the lizard cerebral cortex.

    PubMed Central

    Bernabeu, A; Martinez-Guijarro, F J; de la Iglesia, J A; Lopez-Garcia, C

    1994-01-01

    The morphology and synaptic organisation of a type of multipolar neuron of the lizard cerebral cortex were studied by Golgi impregnation, intracellular injection of horseradish peroxidase, electron microscopy, and immunocytochemistry. It is a GABA-immunoreactive interneuron and most likely parvalbumin-immunoreactive. Its conspicuous axonal arbor is characterised by an initial segment arising from the soma or from a juxtasomatic dendritic segment. The initial axon segment ramifies and gives rise to thick myelinated segments that terminate in short unmyelinated branches studded with thick boutons 'en passant' that (1) make axosomatic synapses on bipyramidal neuronal somata and (2) synapse on initial apical dendritic segments of bipyramidal neurons forming climbing-like cartridges. The dendrites extend throughout the thickness of the cortex, receiving synaptic input from a variety of sources of which the most prominent is that of zinc-positive boutons coming from granule cells of the medial cortex. According to its synaptology, this interneuron may play a role in regulating the activity of bipyramidal neurons by both feed-forward and feed-back inhibition mechanisms. From a comparative standpoint, it may be related to the sparsely spiny or nonspiny multipolar neurons of the stratum oriens of the mammalian hippocampus. Images Fig. 1 Fig. 4 Fig. 6 Fig. 7 Fig. 8 PMID:7928645

  8. Schedule-induced polydipsia is associated with increased spine density in dorsolateral striatum neurons.

    PubMed

    Íbias, J; Soria-Molinillo, E; Kastanauskaite, A; Orgaz, C; DeFelipe, J; Pellón, R; Miguéns, M

    2015-08-01

    Schedule-induced polydipsia (SIP) is an adjunctive behavior in which rats exhibit excessive drinking as a consequence of intermittent feeding, and it has been proposed as a candidate model to study the development of compulsive and repetitive behavior. Although several brain structures are involved in compulsive behavior, it has been suggested that alterations in fronto-striatal circuits may underlie compulsive spectrum disorders. In the present work, we examined whether SIP would induce modifications in dorsolateral striatum (DLS) and anterior prefrontal cortex (aPFC) neurons. Specifically, the effects of 20 sessions of SIP were determined in the dendrites of DLS medium spiny neurons and in the basal dendritic arbors of layer V pyramidal cells in the aPFC. The structure, size and branching complexity in aPFC neurons were also studied. Results showed that SIP resulted in an increase in dendritic spine density in DLS neurons. Moreover, dendritic spine density was highly correlated with the level of drinking in animals subjected to SIP. By contrast, we observed no differences either in dendritic spine density or in the morphological structure of the dendrites of the aPFC in SIP rats compared to their control counterparts. We hypothesize that SIP-induced structural plasticity in DLS neurons could be related to inflexible response in compulsive behavior. The findings of this study could provide new insights into the involvement of particular cell populations of the dorsolateral striatum and anterior prefrontal cortex regions in compulsive spectrum disorders. PMID:25988756

  9. Three-Dimensional Analysis of Spiny Dendrites Using Straightening and Unrolling Transforms

    PubMed Central

    Morales, Juan; Benavides-Piccione, Ruth; Pastor, Luis; Yuste, Rafael; DeFelipe, Javier

    2014-01-01

    Current understanding of the synaptic organization of the brain depends to a large extent on knowledge about the synaptic inputs to the neurons. Indeed, the dendritic surfaces of pyramidal cells (the most common neuron in the cerebral cortex) are covered by thin protrusions named dendritic spines. These represent the targets of most excitatory synapses in the cerebral cortex and therefore, dendritic spines prove critical in learning, memory and cognition. This paper presents a new method that facilitates the analysis of the 3D structure of spine insertions in dendrites, providing insight on spine distribution patterns. This method is based both on the implementation of straightening and unrolling transformations to move the analysis process to a planar, unfolded arrangement, and on the design of DISPINE, an interactive environment that supports the visual analysis of 3D patterns. PMID:22644869

  10. Effect of testosterone undecanoate hormone on sperm and its level in the hemolymph of male mud spiny lobster, Panulirus polyphagus.

    PubMed

    Fatihah, S N; Safiah, J; Abol-Munafi, A B; Ikhwanuddin, M

    2014-07-01

    The present study aimed to determine the effect of testosterone undecanoate hormone on sperm quality (sperm viability) and sperm quantity (sperm counts) and its levels in the hemolymph of male mud spiny lobster, Panulirus polyphagus. Male P. polyphagus was injected laterally in fifth abdominal segment of pure hormone, Testosterone Undecanoate (TU) and ethanol at days 1, 8, 15, 22 and 29. Hemolymph of P. polyphagus was taken every two weeks and checked with Enzyme-linked immunosorbent assay (ELISA) to measure hormone levels. The mean sperm quality and quantity were increased due to increase the TU dose and TU levels also increase. The sperm quality, quantity and hormone levels were relevance each others. These findings indicate that TU injection should be evaluated as a practical way of improving sperm quality and quantity in commercial operations. PMID:26035945

  11. Genetic Isolation among the Northwestern, Southwestern and Central-Eastern Indian Ocean Populations of the Pronghorn Spiny Lobster Panulirus penicillatus

    PubMed Central

    Abdullah, Muhamad Fadry; Alimuddin; Muththalib, Mohamed; Salama, Adnan Jameel; Imai, Hideyuki

    2014-01-01

    The pronghorn spiny lobster Panulirus penicillatus is a highly valuable species which is widely distributed in Indo-West Pacific and Eastern Pacific regions. Mitochondrial DNA control region sequences (566–571 bp) were determined to investigate the population genetic structure of this species in the Indian Ocean. In total, 236 adult individuals of Panulirus penicillatus were collected from five locations in the Indian Ocean region. Almost all individuals had a unique haplotype. Intrapopulation haplotype (h) and nucleotide (π) diversities were high for each locality, ranging from h = 0.9986–1.0000 and π = 0.031593–0.043441. We observed distinct genetic isolation of population located at the northwestern and southwestern edge of the species range. Gene flow was found within localities in the central and eastern region of the Indian Ocean, probably resulting from an extended planktonic larval stage and prevailing ocean currents. PMID:24865488

  12. Genetic isolation among the northwestern, southwestern and central-eastern Indian Ocean populations of the pronghorn spiny lobster Panulirus penicillatus.

    PubMed

    Abdullah, Muhamad Fadry; Alimuddin; Muththalib, Mohamed; Salama, Adnan Jameel; Imai, Hideyuki

    2014-01-01

    The pronghorn spiny lobster Panulirus penicillatus is a highly valuable species which is widely distributed in Indo-West Pacific and Eastern Pacific regions. Mitochondrial DNA control region sequences (566-571 bp) were determined to investigate the population genetic structure of this species in the Indian Ocean. In total, 236 adult individuals of Panulirus penicillatus were collected from five locations in the Indian Ocean region. Almost all individuals had a unique haplotype. Intrapopulation haplotype (h) and nucleotide (π) diversities were high for each locality, ranging from h = 0.9986-1.0000 and π = 0.031593-0.043441. We observed distinct genetic isolation of population located at the northwestern and southwestern edge of the species range. Gene flow was found within localities in the central and eastern region of the Indian Ocean, probably resulting from an extended planktonic larval stage and prevailing ocean currents. PMID:24865488

  13. The effects of lighting conditions and food restriction paradigms on locomotor activity of common spiny mice, Acomys cahirinus

    PubMed Central

    2012-01-01

    Background An endogenous circadian clock controls locomotor activity in common spiny mice (Acomys cahirinus). However, little is known about the effects of constant light (LL) on this activity or about the existence of an additional food entrainable clock. A series of experiments were performed to investigate the effects of LL and DD on tau and activity levels. Methods Spiny mice were housed individually and their running wheel activity monitored. One group of mice was exposed to LD, DD and several intensities of LL. Another group was exposed to a restricted feeding (RF) paradigm in light: dark (LD) during one hour before the L to D transition. Significance of rhythmicity was assessed using Lomb-Scargle periodograms. Results In LD all animals exhibited nocturnal activity rhythms that persisted in DD. When animals were exposed to RF (during L), all of these animals (n = 11) demonstrated significant food anticipatory activity as well as an increase in diurnal activity. This increase in diurnal activity persisted in 4/11 animals during subsequent ad libitum conditions. Under LL conditions, the locomotor rhythms of 2/11 animals appeared to entrain to RF. When animals were exposed to sequentially increasing LL intensities, rhythmicity persisted and, while activity decreased significantly, the free-running period was relatively unaffected. In addition, the period in LL was significantly longer than the period in DD. Exposure to LL also induced long-term changes (after-effects) on period and activity when animals were again exposed to DD. Conclusions Overall these studies demonstrate clear and robust circadian rhythms of wheel-running in A. cahirinus. In addition, LL clearly inhibited activity in this species and induced after-effects. The results also confirm the presence of a food entrainable oscillator in this species. PMID:22958374

  14. [Length of capture and reproduction of green spiny lobster panulirus gracilis (Decapoda: Palinuridae) from the coast of Manabi, Ecuador].

    PubMed

    Figueroa, Juan; Mero, David

    2013-09-01

    Green spiny lobster Panulirus gracilis is an economical resource of high importance for fishermen populations in the continental coast of Ecuador. Traditionally, this specie is captured using gillnets and semiautonomous diving system (hookah). With the objective to analyze some biological aspects about this fishery in Manabi, we examined lengths of capture (carapace length: CL and abdominal length: AL), sex ratio and reproductive aspects in females between June and September 2010. A total of 415 females and 288 males were captured with gillnets in El Mangle-Puerto Cayo (Central coast, depth: 3-6 m), and by diving in Puerto López-Salango (South coast, depth: 7-12 m). Sex ratio from males to females was 0.72:1 for gillnets, and 0.63:1 for diving. Lobsters captured by diving were larger (84.1 +/- 3.3 mm CL) than lobsters captured by gillnets (73.4 +/- 2.9 mm CL). Percentage of ovigerous females captured by diving was higher than females captured by gillnets. There was a pattern between lengths by sex (relation AL vs. CL); females were larger than males at same CL. Differences found between lengths and the occurrence of ovigerous females could be related with depth where capture methods are used. A total of 98% of landed lobsters were smaller than legal captured length and we recommend the establishment of a monitoring evaluation program during the fishing season, and a ban, in order to evaluate the natural fluctuation in length and reproductive stages of green spiny lobster in the coasts of Manabi. PMID:24027917

  15. Dopamine Receptor Blockade Modulates the Rewarding and Aversive Properties of Nicotine via Dissociable Neuronal Activity Patterns in the Nucleus Accumbens

    PubMed Central

    Sun, Ninglei; Laviolette, Steven R

    2014-01-01

    The mesolimbic pathway comprising the ventral tegmental area (VTA) and projection terminals in the nucleus accumbens (NAc) has been identified as a critical neural system involved in processing both the rewarding and aversive behavioral effects of nicotine. Transmission through dopamine (DA) receptors functionally modulates these effects directly within the NAc. Nevertheless, the neuronal mechanisms within the NAc responsible for these bivalent behavioral effects are presently not known. Using an unbiased conditioned place preference procedure combined with in vivo neuronal recordings, we examined the effects of nicotine reward and aversion conditioning on intra-NAc neuronal sub-population activity patterns. We report that intra-VTA doses of nicotine that differentially produce rewarding or aversive behavioral effects produce opposite effects on sub-populations of fast-spiking interneurons (FSIs) or medium spiny neurons (MSNs) within the shell region of the NAc (NAshell). Thus, while the rewarding effects of intra-VTA nicotine were associated with inhibition of FSI and activation of MSNs, the aversive effects of nicotine produced the opposite pattern of NAshell neuronal population activity. Blockade of DA transmission with a broad-spectrum DA receptor antagonist, α-flupenthixol, strongly inhibited the spontaneous activity of NAshell FSIs, and reversed the conditioning properties of intra-VTA nicotine, switching nicotine-conditioned responses from aversive to rewarding. Remarkably, DA receptor blockade switched intra-NAshell neuronal population activity from an aversion to a reward pattern, concomitant with the observed switch in behavioral conditioning effects. PMID:24896614

  16. Structure-function correlations of rat trigeminal primary neurons: Emphasis on club-like endings, a vibrissal mechanoreceptor

    PubMed Central

    TONOMURA, Sotatsu; EBARA, Satomi; BAGDASARIAN, Knarik; UTA, Daisuke; AHISSAR, Ehud; MEIR, Inbal; LAMPL, Ilan; KURODA, Daichi; FURUTA, Takahiro; FURUE, Hidemasa; KUMAMOTO, Kenzo

    2015-01-01

    This study focuses on the structure and function of the primary sensory neurons that innervate vibrissal follicles in the rat. Both the peripheral and central terminations, as well as their firing properties were identified using intracellular labelling and recording in trigeminal ganglia in vivo. Fifty-one labelled neurons terminating peripherally, as club-like, Merkel, lanceolate, reticular or spiny endings were identified by their morphology. All neurons responded robustly to air puff stimulation applied to the vibrissal skin. Neurons with club-like endings responded with the highest firing rates; their peripheral processes rarely branched between the cell body and their terminal tips. The central branches of these neurons displayed abundant collaterals terminating within all trigeminal nuclei. Analyses of three-dimensional reconstructions reveal a palisade arrangement of club-like endings bound to the ringwulst by collagen fibers. Our morphological findings suggest that neurons with club-like endings sense mechanical aspects related to the movement of the ringwulst and convey this information to all trigeminal nuclei in the brainstem. PMID:26666306

  17. Efficient generation of region-specific forebrain neurons from human pluripotent stem cells under highly defined condition

    PubMed Central

    Yuan, Fang; Fang, Kai-Heng; Cao, Shi-Ying; Qu, Zhuang-Yin; Li, Qi; Krencik, Robert; Xu, Min; Bhattacharyya, Anita; Su, Yu-Wen; Zhu, Dong-Ya; Liu, Yan

    2015-01-01

    Human pluripotent stem cells (hPSCs) have potential to differentiate to unlimited number of neural cells, which provide powerful tools for neural regeneration. To date, most reported protocols were established with an animal feeder system. However, cells derived on this system are inappropriate for the translation to clinical applications because of the introduction of xenogenetic factors. In this study, we provided an optimized paradigm to generate region-specific forebrain neurons from hPSCs under a defined system. We assessed five conditions and found that a vitronectin-coated substrate was the most efficient method to differentiate hPSCs to neurons and astrocytes. More importantly, by applying different doses of purmorphamine, a small-molecule agonist of sonic hedgehog signaling, hPSCs were differentiated to different region-specific forebrain neuron subtypes, including glutamatergic neurons, striatal medium spiny neurons, and GABA interneurons. Our study offers a highly defined system without exogenetic factors to produce human neurons and astrocytes for translational medical studies, including cell therapy and stem cell-based drug discovery. PMID:26670131

  18. Dopamine-induced oscillations of the pyloric pacemaker neuron rely on release of calcium from intracellular stores.

    PubMed

    Kadiri, Lolahon R; Kwan, Alex C; Webb, Watt W; Harris-Warrick, Ronald M

    2011-09-01

    Endogenously bursting neurons play central roles in many aspects of nervous system function, ranging from motor control to perception. The properties and bursting patterns generated by these neurons are subject to neuromodulation, which can alter cycle frequency and amplitude by modifying the properties of the neuron's ionic currents. In the stomatogastric ganglion (STG) of the spiny lobster, Panulirus interruptus, the anterior burster (AB) neuron is a conditional oscillator in the presence of dopamine (DA) and other neuromodulators and serves as the pacemaker to drive rhythmic output from the pyloric network. We analyzed the mechanisms by which DA evokes bursting in the AB neuron. Previous work showed that DA-evoked bursting is critically dependent on external calcium (Harris-Warrick RM, Flamm RE. J Neurosci 7: 2113-2128, 1987). Using two-photon microscopy and calcium imaging, we show that DA evokes the release of calcium from intracellular stores well before the emergence of voltage oscillations. When this release from intracellular stores is blocked by antagonists of ryanodine or inositol trisphosphate (IP(3)) receptor channels, DA fails to evoke AB bursting. We further demonstrate that DA enhances the calcium-activated inward current, I(CAN), despite the fact that it significantly reduces voltage-activated calcium currents. This suggests that DA-induced release of calcium from intracellular stores activates I(CAN), which provides a depolarizing ramp current that underlies endogenous bursting in the AB neuron. PMID:21676929

  19. Temporal filtering properties of ampullary electrosensory neurons in the torus semicircularis of Eigenmannia: evolutionary and computational implications.

    PubMed

    Fortune, E S; Rose, G J

    1997-01-01

    Weakly electric fish have parallel electrosensory systems, the phylogenetically older ampullary system and the novel tuberous system. The tuberous system is an adaptation related to the evolution of active electrolocation. To examine the evolutionary relationship of the ampullary and tuberous systems, the temporal filtering properties of ampullary neurons in the dorsal torus semicircularis of Eigenmannia were studied. 'Whole-cell' recordings were made in vivo using patch-type pipettes. The responses of 19 neurons to sinusoidal electric signals (< 40 Hz) were recorded and the anatomy of these neurons demonstrated by injection of biocytin. All eight low-pass ampullary neurons had broad, relatively smooth post-synaptic potentials (psps) that at low frequencies nicely reflected the sinusoidal stimuli. These neurons had somata of 10-14 microns diameter and thick, spiny dendrites. Eight high-pass neurons were recorded, representing three physiological classes. The first class (3 neurons) had psps that roughly followed the sinusoidal time course of the stimulus; the psp morphology was similar to low-pass neurons. The second class had many small, fast, individual psps; their rate of occurrence varied with the stimulus. Finally, four neurons showed psps that were of constant width across stimulus frequencies. All three classes of high-pass neurons had small somata (8-10 microns diameter) with thin dendrites and either few or no spines. Some of these neurons had large varicosities on the dendrites. Three neurons had band-pass filtering properties: neurons that showed strong band-pass properties were morphologically similar to low-pass neurons. Comparisons of the temporal filtering, shapes of post-synaptic potentials, and anatomy of ampullary and tuberous neurons in the torus suggest that the circuitry for tuberous processing in the torus may have evolved as an elaboration or duplication of the ampullary system. The mechanisms underlying the low-pass filtering characteristics

  20. Linear integration of spine Ca2+ signals in layer 4 cortical neurons in vivo

    PubMed Central

    Jia, Hongbo; Varga, Zsuzsanna; Sakmann, Bert; Konnerth, Arthur

    2014-01-01

    Sensory information reaches the cortex through synchronously active thalamic axons, which provide a strong drive to layer 4 (L4) cortical neurons. Because of technical limitations, the dendritic signaling processes underlying the rapid and efficient activation of L4 neurons in vivo remained unknown. Here we introduce an approach that allows the direct monitoring of single dendritic spine Ca2+ signals in L4 spiny stellate cells of the vibrissal mouse cortex in vivo. Our results demonstrate that activation of N-methyl-D-aspartate (NMDA) receptors is required for sensory-evoked action potential (AP) generation in these neurons. By analyzing NMDA receptor-mediated Ca2+ signaling, we identify whisker stimulation-evoked large responses in a subset of dendritic spines. These sensory-stimulation–activated spines, representing predominantly thalamo-cortical input sites, were denser at proximal dendritic regions. The amplitude of sensory-evoked spine Ca2+ signals was independent of the activity of neighboring spines, without evidence for cooperativity. Furthermore, we found that spine Ca2+ signals evoked by back-propagating APs sum linearly with sensory-evoked synaptic Ca2+ signals. Thus, our results identify in sensory information-receiving L4 cortical neurons a linear mode of dendritic integration that underlies the rapid and reliable transfer of peripheral signals to the cortical network. PMID:24927564

  1. Dietary creatine supplementation during pregnancy: a study on the effects of creatine supplementation on creatine homeostasis and renal excretory function in spiny mice.

    PubMed

    Ellery, Stacey J; LaRosa, Domenic A; Kett, Michelle M; Della Gatta, Paul A; Snow, Rod J; Walker, David W; Dickinson, Hayley

    2016-08-01

    Recent evidence obtained from a rodent model of birth asphyxia shows that supplementation of the maternal diet with creatine during pregnancy protects the neonate from multi-organ damage. However, the effect of increasing creatine intake on creatine homeostasis and biosynthesis in females, particularly during pregnancy, is unknown. This study assessed the impact of creatine supplementation on creatine homeostasis, body composition, capacity for de novo creatine synthesis and renal excretory function in non-pregnant and pregnant spiny mice. Mid-gestation pregnant and virgin spiny mice were fed normal chow or chow supplemented with 5 % w/w creatine for 18 days. Weight gain, urinary creatine and electrolyte excretion were assessed during supplementation. At post mortem, body composition was assessed by Dual-energy X-ray absorptiometry, or tissues were collected to assess creatine content and mRNA expression of the creatine synthesising enzymes arginine:glycine amidinotransferase (AGAT) and guanidinoacetate methyltransferase (GAMT) and the creatine transporter (CrT1). Protein expression of AGAT and GAMT was also assessed by Western blot. Key findings of this study include no changes in body weight or composition with creatine supplementation; increased urinary creatine excretion in supplemented spiny mice, with increased sodium (P < 0.001) and chloride (P < 0.05) excretion in pregnant dams after 3 days of supplementation; lowered renal AGAT mRNA (P < 0.001) and protein (P < 0.001) expressions, and lowered CrT1 mRNA expression in the kidney (P < 0.01) and brain (P < 0.001). Creatine supplementation had minimal impact on creatine homeostasis in either non-pregnant or pregnant spiny mice. Increasing maternal dietary creatine consumption could be a useful treatment for birth asphyxia. PMID:26695944

  2. MeCP2 phosphorylation limits psychostimulant-induced behavioral and neuronal plasticity.

    PubMed

    Deng, Jie V; Wan, Yehong; Wang, Xiaoting; Cohen, Sonia; Wetsel, William C; Greenberg, Michael E; Kenny, Paul J; Calakos, Nicole; West, Anne E

    2014-03-26

    The methyl-DNA binding protein MeCP2 is emerging as an important regulator of drug reinforcement processes. Psychostimulants induce phosphorylation of MeCP2 at Ser421; however, the functional significance of this posttranslational modification for addictive-like behaviors was unknown. Here we show that MeCP2 Ser421Ala knock-in mice display both a reduced threshold for the induction of locomotor sensitization by investigator-administered amphetamine and enhanced behavioral sensitivity to the reinforcing properties of self-administered cocaine. These behavioral differences were accompanied in the knock-in mice by changes in medium spiny neuron intrinsic excitability and nucleus accumbens gene expression typically observed in association with repeated exposure to these drugs. These data show that phosphorylation of MeCP2 at Ser421 functions to limit the circuit plasticities in the nucleus accumbens that underlie addictive-like behaviors. PMID:24671997

  3. MeCP2 Phosphorylation Limits Psychostimulant-Induced Behavioral and Neuronal Plasticity

    PubMed Central

    Deng, Jie V.; Wan, Yehong; Wang, Xiaoting; Cohen, Sonia; Wetsel, William C.; Greenberg, Michael E.; Kenny, Paul J.; Calakos, Nicole

    2014-01-01

    The methyl-DNA binding protein MeCP2 is emerging as an important regulator of drug reinforcement processes. Psychostimulants induce phosphorylation of MeCP2 at Ser421; however, the functional significance of this posttranslational modification for addictive-like behaviors was unknown. Here we show that MeCP2 Ser421Ala knock-in mice display both a reduced threshold for the induction of locomotor sensitization by investigator-administered amphetamine and enhanced behavioral sensitivity to the reinforcing properties of self-administered cocaine. These behavioral differences were accompanied in the knock-in mice by changes in medium spiny neuron intrinsic excitability and nucleus accumbens gene expression typically observed in association with repeated exposure to these drugs. These data show that phosphorylation of MeCP2 at Ser421 functions to limit the circuit plasticities in the nucleus accumbens that underlie addictive-like behaviors. PMID:24671997

  4. Reappraising striatal D1- and D2-neurons in reward and aversion.

    PubMed

    Soares-Cunha, Carina; Coimbra, Barbara; Sousa, Nuno; Rodrigues, Ana J

    2016-09-01

    The striatum has been involved in complex behaviors such as motor control, learning, decision-making, reward and aversion. The striatum is mainly composed of medium spiny neurons (MSNs), typically divided into those expressing dopamine receptor D1, forming the so-called direct pathway, and those expressing D2 receptor (indirect pathway). For decades it has been proposed that these two populations exhibit opposing control over motor output, and recently, the same dichotomy has been proposed for valenced behaviors. Whereas D1-MSNs mediate reinforcement and reward, D2-MSNs have been associated with punishment and aversion. In this review we will discuss pharmacological, genetic and optogenetic studies that indicate that there is still controversy to what concerns the role of striatal D1- and D2-MSNs in this type of behaviors, highlighting the need to reconsider the early view that they mediate solely opposing aspects of valenced behaviour. PMID:27235078

  5. The use of satellite tags to redefine movement patterns of spiny dogfish (Squalus acanthias) along the U.S. east coast: implications for fisheries management.

    PubMed

    Carlson, Amy E; Hoffmayer, Eric R; Tribuzio, Cindy A; Sulikowski, James A

    2014-01-01

    Spiny dogfish (Squalus acanthias) are assumed to be a highly migratory species, making habitual north-south migrations throughout their northwestern Atlantic United States (U.S.) range. Also assumed to be a benthic species, spiny dogfish stock structure is estimated through Northeast Fisheries Science Center (NEFSC) bottom-trawl surveys. Recent anomalies in population trends, including a recent four-fold increase in estimated spawning stock biomass, suggest alternative movement patterns could exist for this shark species. To obtain a better understanding of the horizontal and vertical movement dynamics of this species, Microwave Telemetry pop-up satellite archival X-Tags were attached to forty adult spiny dogfish at the northern (Gulf of Maine) and southern (North Carolina) extents of their core U.S. geographic range. Reconstructed geolocation tracks ranging in lengths from two to 12 months suggest that the seasonal migration patterns appear to be local in nature to each respective northern and southern deployment site, differing from previously published migration paradigms. Differences in distance and direction traveled between seasonal geolocations possibly indicate separate migratory patterns between groups. Kernel utilization distribution models also suggest strong separate core home ranges. Significant differences in seasonal temperature and depths between the two regions further substantiate the possibility of separate regional movement patterns between the two groups. Vertical utilization also suggests distinct diel patterns and that this species may not utilize the benthos as previously thought, potentially decreasing availability to benthic gear. PMID:25068584

  6. Mercury concentrations in Northwest Atlantic winter-caught, male spiny dogfish (Squalus acanthias): A geographic mercury comparison and risk-reward framework for human consumption.

    PubMed

    St Gelais, Adam T; Costa-Pierce, Barry A

    2016-01-15

    Mercury (Hg) contamination testing was conducted on winter-caught male spiny dogfish (Squalus acanthias) in southern New England and results compared to available data on Hg concentrations for this species. A limited risk-reward assessment for EPA (eicosapentanoic acid) and DHA (docosahexanoic acid) lipid concentrations of spiny dogfish was completed in comparison with other commonly consumed marine fish. Mean Hg concentrations were 0.19 ppm (±0.30) wet weight. In comparison, mean Hg concentrations in S. acanthias varied geographically ranging from 0.05 ppm (Celtic Sea) to 2.07 ppm (Crete, Mediterranean Sea). A risk-reward assessment for Hg and DHA+EPA placed S. acanthias in both "low-risk, high-reward" and "high-risk, high-reward" categories for consumption dependent on locations of the catch. Our results are limited and are not intended as consumption advisories but serve to illustrate the need for making more nuanced, geo-specific, consumption guidance for spiny dogfish that is inclusive of seafood traceability and nutritional benefits. PMID:26707980

  7. Seismic air gun exposure during early-stage embryonic development does not negatively affect spiny lobster Jasus edwardsii larvae (Decapoda: Palinuridae).

    PubMed

    Day, Ryan D; McCauley, Robert D; Fitzgibbon, Quinn P; Semmens, Jayson M

    2016-01-01

    Marine seismic surveys are used to explore for sub-seafloor oil and gas deposits. These surveys are conducted using air guns, which release compressed air to create intense sound impulses, which are repeated around every 8-12 seconds and can travel large distances in the water column. Considering the ubiquitous worldwide distribution of seismic surveys, the potential impact of exposure on marine invertebrates is poorly understood. In this study, egg-bearing female spiny lobsters (Jasus edwardsii) were exposed to signals from three air gun configurations, all of which exceeded sound exposure levels (SEL) of 185 dB re 1 μPa(2) · s. Lobsters were maintained until their eggs hatched and the larvae were then counted for fecundity, assessed for abnormal morphology using measurements of larval length and width, tested for larval competency using an established activity test and measured for energy content. Overall there were no differences in the quantity or quality of hatched larvae, indicating that the condition and development of spiny lobster embryos were not adversely affected by air gun exposure. These results suggest that embryonic spiny lobster are resilient to air gun signals and highlight the caution necessary in extrapolating results from the laboratory to real world scenarios or across life history stages. PMID:26947006

  8. The Use of Satellite Tags to Redefine Movement Patterns of Spiny Dogfish (Squalus acanthias) along the U.S. East Coast: Implications for Fisheries Management

    PubMed Central

    Carlson, Amy E.; Hoffmayer, Eric R.; Tribuzio, Cindy A.; Sulikowski, James A.

    2014-01-01

    Spiny dogfish (Squalus acanthias) are assumed to be a highly migratory species, making habitual north-south migrations throughout their northwestern Atlantic United States (U.S.) range. Also assumed to be a benthic species, spiny dogfish stock structure is estimated through Northeast Fisheries Science Center (NEFSC) bottom-trawl surveys. Recent anomalies in population trends, including a recent four-fold increase in estimated spawning stock biomass, suggest alternative movement patterns could exist for this shark species. To obtain a better understanding of the horizontal and vertical movement dynamics of this species, Microwave Telemetry pop-up satellite archival X-Tags were attached to forty adult spiny dogfish at the northern (Gulf of Maine) and southern (North Carolina) extents of their core U.S. geographic range. Reconstructed geolocation tracks ranging in lengths from two to 12 months suggest that the seasonal migration patterns appear to be local in nature to each respective northern and southern deployment site, differing from previously published migration paradigms. Differences in distance and direction traveled between seasonal geolocations possibly indicate separate migratory patterns between groups. Kernel utilization distribution models also suggest strong separate core home ranges. Significant differences in seasonal temperature and depths between the two regions further substantiate the possibility of separate regional movement patterns between the two groups. Vertical utilization also suggests distinct diel patterns and that this species may not utilize the benthos as previously thought, potentially decreasing availability to benthic gear. PMID:25068584

  9. Seismic air gun exposure during early-stage embryonic development does not negatively affect spiny lobster Jasus edwardsii larvae (Decapoda:Palinuridae)

    PubMed Central

    Day, Ryan D.; McCauley, Robert D.; Fitzgibbon, Quinn P.; Semmens, Jayson M.

    2016-01-01

    Marine seismic surveys are used to explore for sub-seafloor oil and gas deposits. These surveys are conducted using air guns, which release compressed air to create intense sound impulses, which are repeated around every 8–12 seconds and can travel large distances in the water column. Considering the ubiquitous worldwide distribution of seismic surveys, the potential impact of exposure on marine invertebrates is poorly understood. In this study, egg-bearing female spiny lobsters (Jasus edwardsii) were exposed to signals from three air gun configurations, all of which exceeded sound exposure levels (SEL) of 185 dB re 1 μPa2·s. Lobsters were maintained until their eggs hatched and the larvae were then counted for fecundity, assessed for abnormal morphology using measurements of larval length and width, tested for larval competency using an established activity test and measured for energy content. Overall there were no differences in the quantity or quality of hatched larvae, indicating that the condition and development of spiny lobster embryos were not adversely affected by air gun exposure. These results suggest that embryonic spiny lobster are resilient to air gun signals and highlight the caution necessary in extrapolating results from the laboratory to real world scenarios or across life history stages. PMID:26947006

  10. Electrophysiological characterization of neurons in the dorsolateral pontine REM sleep induction zone of the rat: intrinsic membrane properties and responses to carbachol and orexins

    PubMed Central

    Brown§, Ritchie E.; Winston, Stuart; Basheer, Radhika; Thakkar, Mahesh M; McCarley, Robert W.

    2006-01-01

    Pharmacological, lesion and single-unit recording techniques in several animal species have identified a region of the pontine reticular formation (Subcoeruleus, SubC) just ventral to the locus coeruleus as critically involved in the generation of rapid-eye-movement (REM) sleep. However, the intrinsic membrane properties and responses of SubC neurons to neurotransmitters important in REM sleep control, such as acetylcholine and orexins/hypocretins, have not previously been examined in any animal species and thus were targeted in this study. We obtained whole-cell patch-clamp recordings from visually identified SubC neurons in rat brain slices in vitro. Two groups of large neurons (mean diameter 30 and 27μm) were tentatively identified as cholinergic (rostral SubC) and noradrenergic (caudal SubC) neurons. SubC reticular neurons (non-cholinergic, non-noradrenergic) showed a medium-sized depolarizing sag during hyperpolarizing current pulses and often had a rebound depolarization (low-threshold spike, LTS). During depolarizing current pulses they exhibited little adaptation and fired maximally at 30–90 Hz. Those SubC reticular neurons excited by carbachol (n=27) fired spontaneously at 6 Hz, often exhibited a moderately sized LTS, and varied widely in size (17–42 μm). Carbachol-inhibited SubC reticular neurons were medium-sized (15–25 μm) and constituted two groups. The larger group (n=22) was silent at rest and possessed a prominent LTS and associated 1–4 action potentials. The second, smaller group (n=8) had a delayed return to baseline at the offset of hyperpolarizing pulses. Orexins excited both carbachol excited and carbachol inhibited SubC reticular neurons. SubC reticular neurons had intrinsic membrane properties and responses to carbachol similar to those described for other reticular neurons but a larger number of carbachol inhibited neurons were found (> 50 %), the majority of which demonstrated a prominent LTS and may correspond to PGO-on neurons

  11. Electrophysiology of the mammillary complex in vitro. I. Tuberomammillary and lateral mammillary neurons

    NASA Technical Reports Server (NTRS)

    Llinas, R. R.; Alonso, A.

    1992-01-01

    1. The electrophysiological properties of the tuberomammillary and lateral mammillary neurons in the guinea pig mammillary body were studied using an in vitro brain slice preparation. 2. Tuberomammillary (n = 79) neurons were recorded mainly ventral to the lateral mammillary body as well as ventromedially to the fornix within the rostral part of the medial mammillary nucleus. Intracellular staining with horseradish peroxidase (n = 9) and Lucifer yellow (n = 3) revealed that these cells have several thick, long, spiny dendrites emerging from large (20-35 microns) fusiform somata. 3. Most tuberomammillary neurons (66%) fired spontaneously at a relatively low frequency (0.5-10 Hz) at the resting membrane potential. The action potentials were broad (2.3 ms) with a prominent Ca(2+)-dependent shoulder on the falling phase. Deep (17.8 mV), long-lasting spike afterhyperpolarizations were largely Ca(2+)-independent. 4. All tuberomammillary neurons recorded displayed pronounced delayed firing when the cells were activated from a potential negative to the resting level. The cells also displayed a delayed return to the baseline at the break of hyperpolarizing pulses applied from a membrane potential level close to firing threshold. Analysis of the voltage- and time dependence of this delayed rectification suggested the presence of a transient outward current similar to the A current (IA). These were not completely blocked by high concentrations of 4-aminopyridine, whereas the delayed onset of firing was always abolished when voltage-dependent Ca2+ conductances were blocked by superfusion with Cd2+. 5. Tuberomammillary neurons also displayed inward rectification in the hyperpolarizing and, primarily, depolarizing range. Block of voltage-gated Na(+)-dependent conductances with tetrodotoxin (TTX) selectively abolished inward rectification in the depolarizing range, indicating the presence of a persistent low-threshold sodium-dependent conductance (gNap). In fact, persistent TTX

  12. Slow Bursting Neurons of Mouse Cortical Layer 6b Are Depolarized by Hypocretin/Orexin and Major Transmitters of Arousal

    PubMed Central

    Wenger Combremont, Anne-Laure; Bayer, Laurence; Dupré, Anouk; Mühlethaler, Michel; Serafin, Mauro

    2016-01-01

    Neurons firing spontaneously in bursts in the absence of synaptic transmission have been previously recorded in different layers of cortical brain slices. It has been suggested that such neurons could contribute to the generation of alternating UP and DOWN states, a pattern of activity seen during slow-wave sleep. Here, we show that in layer 6b (L6b), known from our previous studies to contain neurons highly responsive to the wake-promoting transmitter hypocretin/orexin (hcrt/orx), there is a set of neurons, endowed with distinct intrinsic properties, which displayed a strong propensity to fire spontaneously in rhythmic bursts. In response to small depolarizing steps, they responded with a delayed firing of action potentials which, upon higher depolarizing steps, invariably inactivated and were followed by a depolarized plateau potential and a depolarizing afterpotential. These cells also displayed a strong hyperpolarization-activated rectification compatible with the presence of an Ih current. Most L6b neurons with such properties were able to fire spontaneously in bursts. Their bursting activity was of intrinsic origin as it persisted not only in presence of blockers of ionotropic glutamatergic and GABAergic receptors but also in a condition of complete synaptic blockade. However, a small number of these neurons displayed a mix of intrinsic bursting and synaptically driven recurrent UP and DOWN states. Most of the bursting L6b neurons were depolarized and excited by hcrt/orx through a direct postsynaptic mechanism that led to tonic firing and eventually inactivation. Similarly, they were directly excited by noradrenaline, histamine, dopamine, and neurotensin. Finally, the intracellular injection of these cells with dye and their subsequent Neurolucida reconstruction indicated that they were spiny non-pyramidal neurons. These results lead us to suggest that the propensity for slow rhythmic bursting of this set of L6b neurons could be directly impeded by hcrt

  13. The feto-placental unit, and potential roles of dehydroepiandrosterone (DHEA) in prenatal and postnatal brain development: A re-examination using the spiny mouse.

    PubMed

    Quinn, Tracey A; Ratnayake, Udani; Dickinson, Hayley; Castillo-Melendez, Margie; Walker, David W

    2016-06-01

    Synthesis of dehydroepiandrosterone (DHEA) by the fetal adrenal gland is important for placental oestrogen production, and may also be important for modulating the effects of glucocorticoids on the developing brain. We have preciously shown that the enzymes and accessory proteins needed for DHEA synthesis-cytochrome P450 enzyme 17α-hydroxylase/17,20 lyase (P450c17), cytochrome-b5 (Cytb5), 3β-hydroxysteroid dehydrogenase (3βHSD)-are expressed in the adrenal gland from 30 days gestation, and DHEA, cortisol and aldosterone are present in fetal plasma from this time. Explant culture of fetal adrenal tissue showed that the spiny mouse adrenal gland, can synthesize and secrete DHEA from at least 0.75 of gestation, and suggest that DHEA may have an important role(s) in placental biosynthesis of oestrogens and in modulating the actions of glucocorticoids in the developing brain in this species. Post-natally, increased immuno-expression of P450c17 and Cytb5 expression in the zona reticularis of the adrenal gland and a significant increase in the synthesis and secretion of DHEA in plasma from 8 to 20 days of age in the spiny mouse, are representative of a period of high adrenal androgen production consistent with the human phenomenon of adrenarche. The studies summarised in this review also show that DHEA is produced de novo in the developing brain of the spiny mouse. These results showed that the spiny mouse brain can indeed produce DHEA from pregnenolone in a time-dependant manner, and coupled with the identification of P450c17 and Cytb5 protein in several regions of the brain, support the idea that DHEA is an endogenous neuro-active steroid in this species. Together, the studies outlined in this review indicate that the androgen DHEA is an important hormone of adrenal and Central Nervous System (CNS) origin in the fetal and postnatal spiny mouse. Disturbance of the development of these fetal tissues, and/or of the relationship between the fetal adrenal gland and

  14. Antagonism of Dopamine Receptor 2 Long Affects Cannabinoid Receptor 1 Signaling in a Cell Culture Model of Striatal Medium Spiny Projection Neurons.

    PubMed

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

    2016-06-01

    Activation of dopamine receptor 2 long (D2L) switches the signaling of type 1 cannabinoid receptor (CB1) from Gαi to Gαs, a process thought to be mediated through CB1-D2L heteromerization. Given the clinical importance of D2 antagonists, the goal of this study was to determine if D2 antagonists could modulate CB1 signaling. Interactions between CB1 and D2L, Gαi, Gαs, and β-arrestin1 were studied using bioluminescence resonance energy transfer 2 (BRET(2)) in STHdh(Q7/Q7) cells. CB1-dependent extracellular regulated kinase (ERK)1/2, CREB phosphorylation, and CB1 internalization following cotreatment of CB1 agonist and D2 antagonist were quantified. Preassembled CB1-Gαi complexes were detected by BRET(2) Arachidonyl-2'-chloroethylamide (ACEA), a selective CB1 agonist, caused a rapid and transient increase in BRET efficiency (BRETEff) between Gαi-Rluc and CB1-green fluorescent protein 2 (GFP(2)), and a Gαi-dependent increase in ERK phosphorylation. Physical interactions between CB1 and D2L were observed using BRET(2) Cotreatment of STHdh(Q7/Q7) cells with ACEA and haloperidol, a D2 antagonist, inhibited BRETEff signals between Gαi-Rluc and CB1-GFP(2) and reduced the EMax and pEC50 of ACEA-mediated Gαi-dependent ERK phosphorylation. ACEA and haloperidol cotreatments produced a delayed and sustained increase in BRETEff between Gαs-Rluc and CB1-GFP(2) and increased the EMax and pEC50 of ACEA-induced Gαs-dependent cAMP response element-binding protein phosphorylation. In cells expressing CB1 and D2L treated with ACEA, binding of haloperidol to D2 receptors switched CB1 coupling from Gαi to Gαs In addition, haloperidol treatment reduced ACEA-induced β-arrestin1 recruitment to CB1 and CB1 internalization. D2 antagonists allosterically modulate cannabinoid-induced CB1 coupling, signaling, and β-arrestin1 recruitment through binding to CB1-D2L heteromers. These findings indicate that D2 antagonism, like D2 agonists, change agonist-mediated CB1 coupling and signaling. PMID:27053685

  15. Influence of conspecific and heterospecific aggregation cues and alarm odors on shelter choice by syntopic spiny lobsters.

    PubMed

    Briones-Fourzán, Patricia; Ramírez-Zaldívar, Eunice; Lozano-Alvarez, Enrique

    2008-10-01

    In spiny lobsters, conspecific scents ("aggregation cues") may mediate gregarious diurnal sheltering, but scents from injured conspecifics ("alarm odors") may elicit avoidance behavior. In laboratory experiments, individuals of two coexisting species, Panulirus guttatus (a reef-obligate) and P. argus (a temporary reef-dweller), significantly chose shelters emanating conspecific aggregation cues and responded randomly to shelters emanating heterospecific aggregation cues. However, despite evidence that the two species perceived each other's alarm odors to a similar extent, P. guttatus responded randomly to shelters emanating either conspecific or heterospecific alarm odors, whereas P. argus significantly avoided both. This differential influence of alarm odors likely reflects interspecific differences in life history, sociality, and behavior. The less social, reef-obligate P. guttatus lobsters forage close to their reef dens, into which they retract deeply upon perception of risk. This cryptic behavior may offset the need to avoid conspecific (and heterospecific) alarm odors. In contrast, avoidance of conspecific alarm odors by P. argus is consistent with its ontogenetic habitat shifts and greater sociality. Furthermore, because reef-dwelling P. argus lobsters forage across open areas away from the reef, an ability to avoid alarm odors from P. guttatus upon returning to their reef dens may increase their fitness. PMID:18840779

  16. Towards a Supertree of Arthropoda: A Species-Level Supertree of the Spiny, Slipper and Coral Lobsters (Decapoda: Achelata)

    PubMed Central

    Davis, Katie E.; Hesketh, Thomas W.; Delmer, Cyrille; Wills, Matthew A.

    2015-01-01

    While supertrees have been built for many vertebrate groups (notably birds, mammals and dinosaurs), invertebrates have attracted relatively little attention. The paucity of supertrees of arthropods is particularly surprising given their economic and ecological importance, as well as their overwhelming contribution to biodiversity. The absence of comprehensive archives of machine-readable source trees, coupled with the need for software implementing repeatable protocols for managing them, has undoubtedly impeded progress. Here we present a supertree of Achelata (spiny, slipper and coral lobsters) as a proof of concept, constructed using new supertree specific software (the Supertree Toolkit; STK) and following a published protocol. We also introduce a new resource for archiving and managing published source trees. Our supertree of Achelata is synthesised from morphological and molecular source trees, and represents the most complete species-level tree of the group to date. Our findings are consistent with recent taxonomic treatments, confirming the validity of just two families: Palinuridae and Scyllaridae; Synaxidae were resolved within Palinuridae. Monophyletic Silentes and Stridentes lineages are recovered within Palinuridae, and all sub-families within Scyllaridae are found to be monophyletic with the exception of Ibacinae. We demonstrate the feasibility of building larger supertrees of arthropods, with the ultimate objective of building a complete species-level phylogeny for the entire phylum using a divide and conquer strategy. PMID:26461106

  17. Coexistence of congeneric spiny lobsters on coral reefs: differential use of shelter resources and vulnerability to predators

    NASA Astrophysics Data System (ADS)

    Lozano-Álvarez, E.; Briones-Fourzán, P.; Osorio-Arciniegas, A.; Negrete-Soto, F.; Barradas-Ortiz, C.

    2007-06-01

    The notion, previously generated from laboratory experiments, that the local coexistence of spiny lobsters Panulirus guttatus and Panulirus argus on Caribbean reefs may be promoted by a differential use of shelter resources and/or vulnerability to predators was explored in a coral reef in Mexico. Multiple regressions with data collected on 11 occasions on fixed back-reef and fore-reef sites suggested that the densities of the congener, other crevice-dwellers, and predators did not significantly affect the density of P. argus in either reef zone, or of P. guttatus on the back-reef, where coexistence of both lobster species was greatest. In contrast, there was a significant negative relationship between predators and the density of P. guttatus on the fore-reef, where this species was dominant. Congeneric cohabitation in dens was less than expected by chance, but this pattern may reflect a differential use of shelter resources rather than interspecific competition. P. guttatus was more prevalent in dens over the middle and upper third of the reef profile, and P. argus over the lower and middle third of the reef profile. Whether individuals cohabited with conspecifics, congeners, or resided solitarily, P. guttatus was more prevalent at the walls and/or ceiling and P. argus on the floor of dens. This differential use of shelter resources may be related to the differential vulnerability to predators, which may have promoted local coexistence of these congeners in reef habitats.

  18. Time course of the acute response of the North Pacific spiny dogfish shark (Squalus suckleyi) to low salinity.

    PubMed

    Guffey, Samuel C; Goss, Greg G

    2014-05-01

    Dogfish are considered stenohaline sharks but are known to briefly enter estuaries. The acute response of North Pacific spiny dogfish (Squalus suckleyi) to lowered salinity was tested by exposing sharks to 21‰ salinity for 48 h. Temporal trends in blood pH, plasma osmolality, CO2, HCO3(-), Na(+), Cl(-), K(+), and urea concentrations, and in the rates of urea efflux and O2 consumption, were quantified. The rate of O2 consumption exhibited cyclic variation and was significantly depressed by lowered salinity. After 9 h, plasma [Cl(-)] stabilized at 9% below initial levels, while plasma [Na(+)] decreased by more than 20% within the first 12 h. Plasma [urea] dropped by 15% between 4 and 6 h, and continued to decrease. The rate of urea efflux increased over time, peaking after 36 h at 72% above the initial rate. Free-swimming sharks subjected to the same salinity challenge survived over 96 h and differed from cannulated sharks with respect to patterns of Na(+) and urea homeostasis. This high-resolution study reveals that dogfish exposed to 21‰ salinity can maintain homeostasis of Cl(-) and pH, but Na(+) and urea continue to be lost, likely accounting for the inability of the dogfish to fully acclimate to reduced salinity. PMID:24518388

  19. Species profiles: Life histories and environmental requirements of coastal fishes and invertebrates (South Florida): Spiny lobster. [Panulirus argus

    SciTech Connect

    Marx, J.M.; Herrnkind, W.F.

    1986-08-01

    The Florida spiny lobster (Panulirus argus) supports major commercial fisheries in south Florida and the Caribbean Sea. Its life history includes several life stages that live in the open ocean, inshore bays, and coastal reefs. The Florida population spawns along deeper offshore reefs in spring and early summer. Fate of locally spawned larvae is uncertain, but significant postlarval recruitment may originate from larvae spawned in foreign waters. After settlement in inshore vegetated habitats, juveniles reach legal harvestable size in about 2 years. The onset of maturity is coincident with a marked emigration offshore. Subsequent seasonal movements cued by reproductive activity and weather disturbances are pronounced. Excessive fishing has caused a decline in the size of the south Florida population and a corresponding reduction in total spawn. The relevance of spawn reduction is uncertain because of questions regarding larval origins and stock-recruitment relations. Water temperatures probably regulate population distribution and the seasonal dynamics of growth and reproduction. Postlarval recruitment is limited to high salinity inshore environments. Hydrodynamic stimuli and water circulation patterns play critical roles throughout the life cycle.

  20. Chemical induction of feeding in California spiny lobster, Panulirus interruptus (randall): responses to molecular weight fractions of abalone

    SciTech Connect

    Zimmer-Faust, R.K.; Michel, W.C.; Tyre, J.E.; Case, J.F.

    1984-01-01

    Molecular weight fractions of abalone muscle were tested for the ability to induce appetitive feeding and locomotor behavior in the spiny lobster, Panulirus interruptus. Fractions of <1000, 1000-10,000 and >10,000 daltons were isolated by ultrafiltrations and gel chromatography from a seawater extract of abalone muscle. The two lower-molecular-weight fractions (<1000, 1000-10,000) were the least stimulatory of the three fractions tested, and both were ineffective as feeding stimulants. Solutions combining any two of the three isolated fractions produced behavioral activity equal to that caused by whole extract; thus, no single fraction was essential to the stimulatory capacity of abalone. The >1000-dalton fraction was also highly stimulatory, meaning that large and not small molecules were essential in initiating feeding. Finally, a 75% ethanol-insoluble component of the <10,000 fraction was effective, while the ethanol-soluble portion was not. Since the insoluble material consisted predominantly of peptides and polypeptides, it is probable that these molecules act as principal stimulants in abalone muscle. 37 references, 1 figure, 4 tables.