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Sample records for motor links nr1

  1. ALS-linked protein disulfide isomerase variants cause motor dysfunction.

    PubMed

    Woehlbier, Ute; Colombo, Alicia; Saaranen, Mirva J; Pérez, Viviana; Ojeda, Jorge; Bustos, Fernando J; Andreu, Catherine I; Torres, Mauricio; Valenzuela, Vicente; Medinas, Danilo B; Rozas, Pablo; Vidal, Rene L; Lopez-Gonzalez, Rodrigo; Salameh, Johnny; Fernandez-Collemann, Sara; Muñoz, Natalia; Matus, Soledad; Armisen, Ricardo; Sagredo, Alfredo; Palma, Karina; Irrazabal, Thergiory; Almeida, Sandra; Gonzalez-Perez, Paloma; Campero, Mario; Gao, Fen-Biao; Henny, Pablo; van Zundert, Brigitte; Ruddock, Lloyd W; Concha, Miguel L; Henriquez, Juan P; Brown, Robert H; Hetz, Claudio

    2016-04-15

    Disturbance of endoplasmic reticulum (ER) proteostasis is a common feature of amyotrophic lateral sclerosis (ALS). Protein disulfide isomerases (PDIs) areERfoldases identified as possibleALSbiomarkers, as well as neuroprotective factors. However, no functional studies have addressed their impact on the disease process. Here, we functionally characterized fourALS-linked mutations recently identified in two majorPDIgenes,PDIA1 andPDIA3/ERp57. Phenotypic screening in zebrafish revealed that the expression of thesePDIvariants induce motor defects associated with a disruption of motoneuron connectivity. Similarly, the expression of mutantPDIs impaired dendritic outgrowth in motoneuron cell culture models. Cellular and biochemical studies identified distinct molecular defects underlying the pathogenicity of thesePDImutants. Finally, targetingERp57 in the nervous system led to severe motor dysfunction in mice associated with a loss of neuromuscular synapses. This study identifiesERproteostasis imbalance as a risk factor forALS, driving initial stages of the disease. PMID:26869642

  2. Rhythmic processing in children with developmental dyslexia: auditory and motor rhythms link to reading and spelling.

    PubMed

    Thomson, Jennifer M; Goswami, Usha

    2008-01-01

    Potential links between the language and motor systems in the brain have long attracted the interest of developmental psychologists. In this paper, we investigate a link often observed (e.g., [Wolff, P.H., 2002. Timing precision and rhythm in developmental dyslexia. Reading and Writing, 15 (1), 179-206.] between motor tapping and written language skills. We measure rhythmic finger tapping (paced by a metronome beat versus unpaced) and motor dexterity, phonological and auditory processing in 10-year old children, some of whom had a diagnosis of developmental dyslexia. We report links between paced motor tapping, auditory rhythmic processing and written language development. Motor dexterity does not explain these relationships. In regression analyses, paced finger tapping explained unique variance in reading and spelling. An interpretation based on the importance of rhythmic timing for both motor skills and language development is proposed. PMID:18448317

  3. Formation of NR1/NR2 and NR1/NR3 heterodimers constitutes the initial step in N-methyl-D-aspartate receptor assembly.

    PubMed

    Schüler, Thomas; Mesic, Ivana; Madry, Christian; Bartholomäus, Ingo; Laube, Bodo

    2008-01-01

    N-Methyl-D-aspartate (NMDA) receptors are tetrameric protein complexes composed of the glycine-binding NR1 subunit with a glutamate-binding NR2 and/or glycine-binding NR3 subunit. Tri-heteromeric receptors containing NR1, NR2, and NR3 subunits reconstitute channels, which differ strikingly in many properties from the respective glycine- and glutamate-gated NR1/NR2 complexes and the NR1/NR3 receptors gated by glycine alone. Therefore, an accurate oligomerization process of the different subunits has to assure proper NMDA receptor assembly, which has been assumed to occur via the oligomerization of homodimers. Indeed, using fluorescence resonance energy transfer analysis of differentially fluorescence-tagged subunits and blue native polyacrylamide gel electrophoresis after metabolic labeling and affinity purification revealed that the NR1 subunit is capable of forming homo-oligomeric aggregates. In contrast, both the NR2 and the NR3 subunits formed homo- and hetero-oligomers only in the presence of the NR1 subunit indicating differential roles of the subunits in NMDA receptor assembly. However, co-expression of the NR3A subunit with an N-terminal domain-deleted NR1 subunit (NR1(DeltaNTD)) abrogating NR1 homo-oligomerization did not affect NR1/NR3A receptor stoichiometry or function. Hence, homo-oligomerization of the NR1 subunit is not essential for proper NR1/NR3 receptor assembly. Because identical results were obtained for NR1(DeltaNTD)/NR2 NMDA receptors (Madry, C., Mesic, I., Betz, H., and Laube, B. (2007) Mol. Pharmacol., 72, 1535-1544) and NR1-containing hetero-oligomers are readily formed, we assume that heterodimerization of the NR1 with an NR3 or NR2 subunit, which is followed by the subsequent association of two heterodimers, is the key step in determining proper NMDA receptor subunit assembly and stoichiometry. PMID:17959602

  4. Bicaudal D Family of Motor Adaptors: Linking Dynein Motility to Cargo Binding.

    PubMed

    Hoogenraad, Casper C; Akhmanova, Anna

    2016-05-01

    Transport of different intracellular cargoes along cytoskeleton filaments is essential for the morphogenesis and function of a broad variety of eukaryotic cells. Intracellular transport is mediated by cytoskeletal motors including myosin, kinesin, and dynein, which are typically linked to various cargoes by adaptor proteins. Recent studies suggest that adaptor proteins can also act as essential transport cofactors, which control motor activity and coordination. Characterization of the evolutionary conserved Bicaudal D (BICD) family of dynein adaptor proteins has provided important insights into the fundamental mechanisms governing cargo trafficking. This review highlights the advances in the current understanding of how BICD adaptors regulate microtubule-based transport and how they contribute to developmental processes and human disease. PMID:26822037

  5. Distribution of NMDA receptor subunit NR1 in Arctic ground squirrel central nervous system

    PubMed Central

    Zhao, Huiwen W.; Christian, Sherri L.; Castillo, Marina R.; Bult-Ito, Abel; Drew, Kelly L.

    2013-01-01

    Hibernation is a natural model of neuroprotection and adult synaptic plasticity. NMDA receptors (NMDAR), which play key roles in excitotoxicity and synaptic plasticity, have not been characterized in a hibernating species. Tolerance to excitotoxicity and cognitive enhancement in Arctic ground squirrels (AGS, Spermophilus parryii) suggests that NMDAR expression may decrease in hibernation and increase upon arousal. NMDAR consist of at least one NMDAR1 (NR1) subunit, which is required for receptor function. Localization of NR1 reflects localization of the majority, if not all, NMDAR complexes. The purpose of this study, therefore, was to characterize the distribution of NR1 subunits in AGS central nervous system using immunohistochemistry. In addition, we compare NR1 expression in hippocampus of hibernating AGS (hAGS) and inter-bout euthermic AGS (ibeAGS) and assess changes in cell somata size using NR1 stained sections in three hippocampal sub-regions (CA1, CA3, and dentate gyrus). For the first time, we report that immunoreactivity of anti-NR1 is widely distributed throughout the central nervous system in AGS and is similar to other species. No differences exist in the expression and distribution of NR1 in hAGS and ibeAGS. However, we report a significant decrease in size of hippocampal CA1 and dentate gyrus NR1-expressing neuronal somata during hibernation torpor. PMID:17097266

  6. Efficiency consideration of DC link soft-switching inverters for motor drive applications

    SciTech Connect

    Lai, J.S.; Young, R.W.; McKeever, J.W.

    1994-12-31

    This paper critically evaluates efficiency of soft switching inverters including an actively clamped resonant dc link inverter and a clamped-mode resonant pole inverter. An analytical approach to evaluating efficiency of the clamped-mode soft switching inverter has been developed. The evaluation results are compared with that of the standard pulse-width-modulation (PWM) inverter. A 50-kW induction motor is used as the variable load, and the inverter efficiency is evaluated under different speed and torque conditions. The clamped-mode soft-switching inverter, although eliminating the switching loss, shows poor efficiency over the entire load range. Under low load conditions, the efficiency profile is even worse. The actively clamped resonant dc link inverter shows highest efficiency over the entire speed and torque range. However, its energy saving over the standard PWM inverter is marginal under full load or high speed conditions.

  7. Motor and Linguistic Linking of Space and Time in the Cerebellum

    PubMed Central

    Oliveri, Massimiliano; Bonnì, Sonia; Turriziani, Patrizia; Koch, Giacomo; Lo Gerfo, Emanuele; Torriero, Sara; Vicario, Carmelo Mario; Petrosini, Laura; Caltagirone, Carlo

    2009-01-01

    Background Recent literature documented the presence of spatial-temporal interactions in the human brain. The aim of the present study was to verify whether representation of past and future is also mapped onto spatial representations and whether the cerebellum may be a neural substrate for linking space and time in the linguistic domain. We asked whether processing of the tense of a verb is influenced by the space where response takes place and by the semantics of the verb. Principal Findings Responses to past tense were facilitated in the left space while responses to future tense were facilitated in the right space. Repetitive transcranial magnetic stimulation (rTMS) of the right cerebellum selectively slowed down responses to future tense of action verbs; rTMS of both cerebellar hemispheres decreased accuracy of responses to past tense in the left space and to future tense in the right space for non-verbs, and to future tense in the right space for state verbs. Conclusions The results suggest that representation of past and future is mapped onto spatial formats and that motor action could represent the link between spatial and temporal dimensions. Right cerebellar, left motor brain networks could be part of the prospective brain, whose primary function is to use past experiences to anticipate future events. Both cerebellar hemispheres could play a role in establishing the grammatical rules for verb conjugation. PMID:19936216

  8. Aluminum adjuvant linked to Gulf War illness induces motor neuron death in mice.

    PubMed

    Petrik, Michael S; Wong, Margaret C; Tabata, Rena C; Garry, Robert F; Shaw, Christopher A

    2007-01-01

    Gulf War illness (GWI) affects a significant percentage of veterans of the 1991 conflict, but its origin remains unknown. Associated with some cases of GWI are increased incidences of amyotrophic lateral sclerosis and other neurological disorders. Whereas many environmental factors have been linked to GWI, the role of the anthrax vaccine has come under increasing scrutiny. Among the vaccine's potentially toxic components are the adjuvants aluminum hydroxide and squalene. To examine whether these compounds might contribute to neuronal deficits associated with GWI, an animal model for examining the potential neurological impact of aluminum hydroxide, squalene, or aluminum hydroxide combined with squalene was developed. Young, male colony CD-1 mice were injected with the adjuvants at doses equivalent to those given to US military service personnel. All mice were subjected to a battery of motor and cognitive-behavioral tests over a 6-mo period postinjections. Following sacrifice, central nervous system tissues were examined using immunohistochemistry for evidence of inflammation and cell death. Behavioral testing showed motor deficits in the aluminum treatment group that expressed as a progressive decrease in strength measured by the wire-mesh hang test (final deficit at 24 wk; about 50%). Significant cognitive deficits in water-maze learning were observed in the combined aluminum and squalene group (4.3 errors per trial) compared with the controls (0.2 errors per trial) after 20 wk. Apoptotic neurons were identified in aluminum-injected animals that showed significantly increased activated caspase-3 labeling in lumbar spinal cord (255%) and primary motor cortex (192%) compared with the controls. Aluminum-treated groups also showed significant motor neuron loss (35%) and increased numbers of astrocytes (350%) in the lumbar spinal cord. The findings suggest a possible role for the aluminum adjuvant in some neurological features associated with GWI and possibly an

  9. PPARA, RXRA, NR1I2 and NR1I3 gene polymorphisms and lipid and lipoprotein levels in a Southern Brazilian population.

    PubMed

    Lima, Luciana O; Almeida, Silvana; Hutz, Mara H; Fiegenbaum, Marilu

    2013-02-01

    Cardiovascular disease is the main cause of death worldwide, and dyslipidemia is an important multifactorial risk factor. Considering the involvement of nuclear receptors in metabolic pathways, and that some of the receptors act in lipid metabolism and homeostasis, the aim of the present study was to investigate the influence of genetic variations in RXRA, PPARA, NR1I2, and NR1I3 on lipid and lipoprotein levels. Five polymorphisms in the aforementioned genes were genotyped in 622 Brazilians of European descent by PCR-RFLP or TaqMan genotyping assays. In general, carriers of the A insertion of RXRA rs11381416 polymorphism showed higher levels of triglyceride (TG; 1.80 ± 1.20 vs. 1.52 ± 1.20 mmol/L; P = 0.020). Moreover, sexual dimorphic association was found (gender*NR1I3 rs2501873 genotype interaction P < 0.001), males with NR1I3 rs2501873 G/G genotype had lower TG levels (ANCOVA, P = 0.009). Our results suggest that polymorphisms in the RXRA and NR1I3 genes influence lipid profile in a Southern Brazilian population. However, these general and gender association require confirmation in subsequent studies. PMID:23079705

  10. Principal role of NR3 subunits in NR1/NR3 excitatory glycine receptor function.

    PubMed

    Madry, Christian; Mesic, Ivana; Bartholomäus, Ingo; Nicke, Annette; Betz, Heinrich; Laube, Bodo

    2007-03-01

    Calcium-permeable N-methyl-d-aspartate (NMDA) receptors are tetrameric cation channels composed of glycine-binding NR1 and glutamate-binding NR2 subunits, which require binding of both glutamate and glycine for efficient channel gating. In contrast, receptors assembled from NR1 and NR3 subunits function as calcium-impermeable excitatory glycine receptors that respond to agonist application only with low efficacy. Here, we show that antagonists of and substitutions within the glycine-binding site of NR1 potentiate NR1/NR3 receptor function up to 25-fold, but inhibition or mutation of the NR3 glycine binding site reduces or abolishes receptor activation. Thus, glycine bound to the NR1 subunit causes auto-inhibition of NR1/NR3 receptors whereas glycine binding to the NR3 subunits is required for opening of the ion channel. Our results establish differential roles of the high-affinity NR3 and low-affinity NR1 glycine-binding sites in excitatory glycine receptor function. PMID:17214961

  11. Deep-brain photoreception links luminance detection to motor output in Xenopus frog tadpoles.

    PubMed

    Currie, Stephen P; Doherty, Gayle H; Sillar, Keith T

    2016-05-24

    Nonvisual photoreceptors are widely distributed in the retina and brain, but their roles in animal behavior remain poorly understood. Here we document a previously unidentified form of deep-brain photoreception in Xenopus laevis frog tadpoles. The isolated nervous system retains sensitivity to light even when devoid of input from classical eye and pineal photoreceptors. These preparations produce regular bouts of rhythmic swimming activity in ambient light but fall silent in the dark. This sensitivity is tuned to short-wavelength UV light; illumination at 400 nm initiates motor activity over a broad range of intensities, whereas longer wavelengths do not cause a response. The photosensitive tissue is located in a small region of caudal diencephalon-this region is necessary to retain responses to illumination, whereas its focal illumination is sufficient to drive them. We present evidence for photoreception via the light-sensitive proteins opsin (OPN)5 and/or cryptochrome 1, because populations of OPN5-positive and cryptochrome-positive cells reside within the caudal diencephalon. This discovery represents a hitherto undescribed vertebrate pathway that links luminance detection to motor output. The pathway provides a simple mechanism for light avoidance and/or may reinforce classical circadian systems. PMID:27166423

  12. Comparison between NOx Evolution Mechanisms of Wild-Type and nr1 Mutant Soybean Leaves 1

    PubMed Central

    Klepper, Lowell

    1990-01-01

    The nr1 soybean (Glycine max [L.] Merr.) mutant does not contain the two constitutive nitrate reductases, one of which is responsible for enzymic conversion of nitrite to NOx (NO + NO2). It was tested for possible nonenzymic NOx formation and evolution because of known chemical reactions between NO2− and plant metabolites and the instability of nitrous acid. It did not evolve NOx during the in vivo NR assay, but intact leaves did evolve small amounts of NOx under dark, anaerobic conditions. Experiments were conducted to compare NO3− reduction, NO2− accumulation, and the NOx evolution processes of the wild type (cv Williams) and the nr1 mutant. In vivo NR assays showed that wild-type leaves had three times more NO3− reducing capacity than the nr1 mutant. NOx evolution from intact, anerobic nr1 leaves was approximately 10 to 20% that from wild-type leaves. Nitrite content of the nr1 mutant leaves was usually higher than wild type due to low NOx evolution. Lag times and threshold NO2− concentrations for NOx evolution were similar for the two genotypes. While only 1 to 2% of NOx from wild type is NO2, the nr1 mutant evolved 15 to 30% NO2. The kinetic patterns of NOx evolution with time weré completely different for the mutant and wild type. Comparisons of light and heat treatments also gave very different results. It is generally accepted that the NOx evolution by wild type is primarily an enzymic conversion of NO2− to NO. However, this report concludes that NOx evolution by the nr1 mutant was due to nonenzymic, chemical reactions between plant metabolites and accumulated NO2− and/or decomposition of nitrous acid. Nonenzymic NOx evolution probably also occurs in wild type to a degree but could be easily masked by high rates of the enzymic process. PMID:16667445

  13. EcoRI restriction endonuclease map of the composite R plasmid NR1.

    PubMed Central

    Tanak, N; Cramer, J H; Rownd, R H

    1976-01-01

    A physical map of the composite R plasmid NR1 has been constructed using specific cleavage of deoxyribonucleic acid (DNA) by the restriction endonuclease EcoR-. Digestion of composite NR1 DNA by EcoRI yields thirteen fragments. The six largest fragments (designated A to F) are from the resistance transfer factor component that harbors the tetracycline resistance genes (RTF-TC). The seven smallest fragments (designated G to M) are from the r-determinants component that harbors the chloramphenicol (CM), streptomycin-spectinomycin (SM/SP), and sulfonamide (SA) resistance genes. The largest fragment of several RTF-TC segregants of NR1 that have deleted the r-determinants component is 0.8 X 10(6) daltons larger than fragment A of composite NR1. Only a part of fragment H of the r-determinants component is amplified in transitioned NR1 DNA in Proteus mirabilis, which consists of multiple, tandem sequences of r-determinants attached to a single copy of the RTF-TC component. Both of these changes can be explained by the locations of the excision sites at the RTF-TC: r-determinants junctions that are involved in the dissociation and reassociation of the RTF-TC and r-determinants components. The thirteen fragments of composite NR1 DNA produced by EcoRI have been ordered using partial digestion techniques. The order of the fragments is: A-D-C-E-F-B-H-I-L-K-G-M-J. The approximate locations of the TC, CM, SM/SP, and SA resistance genes on the EcoRI map were determined by analyzing several deletion mutants of NR1. Images PMID:776943

  14. Phosphorylation of NMDA NR1 subunits in the myenteric plexus during TNBS induced colitis.

    PubMed

    Zhou, QiQi; Caudle, Robert M; Moshiree, Baharak; Price, Donald D; Verne, G Nicholas

    2006-10-01

    N-Methyl-d-aspartic acid (NMDA) receptors are known to function in the mediation of pain and have a significant role in the development of hyperalgesia following inflammation. Serine phosphorylation regulation of NMDA receptor function occurs in a variety of conditions. No studies have demonstrated a change in phosphorylation of enteric NMDA receptors following colonic inflammation. We examined the levels of NMDA NR1 phosphorylation in trinitrobenzene sulfonic acid (TNBS) induced colitis in rats and compared it to protein translation and the development of visceral hypersensitivity. We have previously, demonstrated an increase in the C1 cassette of NR1 mRNA expression at 14, 21, and 28 days following TNBS administration. In this study, we examined the NR1 serine phosphorylation at 14 days following TNBS injection. Male Sprague-Dawley rats (200-250 g) were treated with TNBS (20mg per rat) diluted in 50% ethanol (n=3) and vehicle controls of 50% ethanol (n=3). TNBS and vehicle controls were administered with a 24 gauge catheter inserted into the lumen of the rat colon. The animals were sacrificed at 14 days after induction of the colitis and their distal colon was retrieved for two-dimensional (2D) western blot analysis. Serine phosphorylation of the NR1 subunit with C1 cassette appears at 14 days after TNBS injection. In contrast, there was no NR1-C1 expression in the vehicle controls and untreated normal controls. These results suggest a role for colonic-NMDA receptor phosphorylation in the development of neuronal plasticity following colonic inflammation. Phosphorylation of NR1 may partially explain visceral hypersensitivity present during colonic inflammation. PMID:16942839

  15. Getting back on the beat: links between auditory-motor integration and precise auditory processing at fast time scales.

    PubMed

    Tierney, Adam; Kraus, Nina

    2016-03-01

    The auditory system is unique in its ability to precisely detect the timing of perceptual events and use this information to update motor plans, a skill that is crucial for language. However, the characteristics of the auditory system that enable this temporal precision are only beginning to be understood. Previous work has shown that participants who can tap consistently to a metronome have neural responses to sound with greater phase coherence from trial to trial. We hypothesized that this relationship is driven by a link between the updating of motor output by auditory feedback and neural precision. Moreover, we hypothesized that neural phase coherence at both fast time scales (reflecting subcortical processing) and slow time scales (reflecting cortical processing) would be linked to auditory-motor timing integration. To test these hypotheses, we asked participants to synchronize to a pacing stimulus, and then changed either the tempo or the timing of the stimulus to assess whether they could rapidly adapt. Participants who could rapidly and accurately resume synchronization had neural responses to sound with greater phase coherence. However, this precise timing was limited to the time scale of 10 ms (100 Hz) or faster; neural phase coherence at slower time scales was unrelated to performance on this task. Auditory-motor adaptation therefore specifically depends upon consistent auditory processing at fast, but not slow, time scales. PMID:26750313

  16. Motor Control and Aging: Links to Age-Related Brain Structural, Functional, and Biochemical Effects

    PubMed Central

    Seidler, Rachael D.; Bernard, Jessica A.; Burutolu, Taritonye B.; Fling, Brett W.; Gordon, Mark T.; Gwin, Joseph T.; Kwak, Youngbin; Lipps, David B.

    2009-01-01

    Although connections between cognitive deficits and age-associated brain differences have been elucidated, relationships with motor performance are less well understood. Here, we broadly review age-related brain differences and motor deficits in older adults in addition to cognition-action theories. Age-related atrophy of the motor cortical regions and corpus callosum may precipitate or coincide with motor declines such as balance and gait deficits, coordination deficits, and movement slowing. Correspondingly, degeneration of neurotransmitter systems—primarily the dopaminergic system—may contribute to age-related gross and fine motor declines, as well as to higher cognitive deficits. In general, older adults exhibit involvement of more widespread brain regions for motor control than young adults, particularly the prefrontal cortex and basal ganglia networks. Unfortunately these same regions are the most vulnerable to age-related effects, resulting in an imbalance of “supply and demand”. Existing exercise, pharmaceutical, and motor training interventions may ameliorate motor deficits in older adults. PMID:19850077

  17. Mental representation and mental practice: experimental investigation on the functional links between motor memory and motor imagery.

    PubMed

    Frank, Cornelia; Land, William M; Popp, Carmen; Schack, Thomas

    2014-01-01

    Recent research on mental representation of complex action has revealed distinct differences in the structure of representational frameworks between experts and novices. More recently, research on the development of mental representation structure has elicited functional changes in novices' representations as a result of practice. However, research investigating if and how mental practice adds to this adaptation process is lacking. In the present study, we examined the influence of mental practice (i.e., motor imagery rehearsal) on both putting performance and the development of one's representation of the golf putt during early skill acquisition. Novice golfers (N = 52) practiced the task of golf putting under one of four different practice conditions: mental, physical, mental-physical combined, and no practice. Participants were tested prior to and after a practice phase, as well as after a three day retention interval. Mental representation structures of the putt were measured, using the structural dimensional analysis of mental representation. This method provides psychometric data on the distances and groupings of basic action concepts in long-term memory. Additionally, putting accuracy and putting consistency were measured using two-dimensional error scores of each putt. Findings revealed significant performance improvements over the course of practice together with functional adaptations in mental representation structure. Interestingly, after three days of practice, the mental representations of participants who incorporated mental practice into their practice regime displayed representation structures that were more similar to a functional structure than did participants who did not incorporate mental practice. The findings of the present study suggest that mental practice promotes the cognitive adaptation process during motor learning, leading to more elaborate representations than physical practice only. PMID:24743576

  18. Mental Representation and Mental Practice: Experimental Investigation on the Functional Links between Motor Memory and Motor Imagery

    PubMed Central

    Frank, Cornelia; Land, William M.; Popp, Carmen; Schack, Thomas

    2014-01-01

    Recent research on mental representation of complex action has revealed distinct differences in the structure of representational frameworks between experts and novices. More recently, research on the development of mental representation structure has elicited functional changes in novices' representations as a result of practice. However, research investigating if and how mental practice adds to this adaptation process is lacking. In the present study, we examined the influence of mental practice (i.e., motor imagery rehearsal) on both putting performance and the development of one's representation of the golf putt during early skill acquisition. Novice golfers (N = 52) practiced the task of golf putting under one of four different practice conditions: mental, physical, mental-physical combined, and no practice. Participants were tested prior to and after a practice phase, as well as after a three day retention interval. Mental representation structures of the putt were measured, using the structural dimensional analysis of mental representation. This method provides psychometric data on the distances and groupings of basic action concepts in long-term memory. Additionally, putting accuracy and putting consistency were measured using two-dimensional error scores of each putt. Findings revealed significant performance improvements over the course of practice together with functional adaptations in mental representation structure. Interestingly, after three days of practice, the mental representations of participants who incorporated mental practice into their practice regime displayed representation structures that were more similar to a functional structure than did participants who did not incorporate mental practice. The findings of the present study suggest that mental practice promotes the cognitive adaptation process during motor learning, leading to more elaborate representations than physical practice only. PMID:24743576

  19. Aerospace induction motor actuators driven from a 20-kHz power link

    NASA Technical Reports Server (NTRS)

    Hansen, Irving G.

    1990-01-01

    Aerospace electromechanical actuators utilizing induction motors are under development in sizes up to 40 kW. While these actuators have immediate application to the Advanced Launch System (ALS) program, several potential applications are currently under study including the Advanced Aircraft Program. Several recent advances developed for the Space Station Freedom have allowed induction motors to be selected as a first choice for such applications. Among these technologies are bi-directional electronics and high frequency power distribution techniques. Each of these technologies are discussed with emphasis on their impact upon induction motor operation.

  20. Manipulation gesture effect in visual and auditory presentations: the link between tools in perceptual and motor tasks

    PubMed Central

    Rey, Amandine E.; Roche, Kévin; Versace, Rémy; Chainay, Hanna

    2015-01-01

    There is much behavioral and neurophysiological evidence in support of the idea that seeing a tool activates motor components of action related to the perceived object (e.g., grasping, use manipulation). However, the question remains as to whether the processing of the motor components associated with the tool is automatic or depends on the situation, including the task and the modality of tool presentation. The present study investigated whether the activation of motor components involved in tool use in response to the simple perception of a tool is influenced by the link between prime and target tools, as well as by the modality of presentation, in perceptual or motor tasks. To explore this issue, we manipulated the similarity of gesture involved in the use of the prime and target (identical, similar, different) with two tool presentation modalities of the presentation tool (visual or auditory) in perceptual and motor tasks. Across the experiments, we also manipulated the relevance of the prime (i.e., associated or not with the current task). The participants saw a first tool (or heard the sound it makes), which was immediately followed by a second tool on which they had to perform a perceptual task (i.e., indicate whether the second tool was identical to or different from the first tool) or a motor task (i.e., manipulate the second tool as if it were the first tool). In both tasks, the similarity between the gestures employed for the first and the second tool was manipulated (Identical, Similar or Different gestures). The results showed that responses were faster when the manipulation gestures for the two tools were identical or similar, but only in the motor task. This effect was observed irrespective of the modality of presentation of the first tool, i.e., visual or auditory. We suggest that the influence of manipulation gesture on response time depends on the relevance of the first tool in motor tasks. We discuss these motor activation results in terms of the

  1. Effective Connectivity Hierarchically Links Temporoparietal and Frontal Areas of the Auditory Dorsal Stream with the Motor Cortex Lip Area during Speech Perception

    ERIC Educational Resources Information Center

    Murakami, Takenobu; Restle, Julia; Ziemann, Ulf

    2012-01-01

    A left-hemispheric cortico-cortical network involving areas of the temporoparietal junction (Tpj) and the posterior inferior frontal gyrus (pIFG) is thought to support sensorimotor integration of speech perception into articulatory motor activation, but how this network links with the lip area of the primary motor cortex (M1) during speech…

  2. From action representation to action execution: exploring the links between cognitive and biomechanical levels of motor control

    PubMed Central

    Land, William M.; Volchenkov, Dima; Bläsing, Bettina E.; Schack, Thomas

    2013-01-01

    Along with superior performance, research indicates that expertise is associated with a number of mediating cognitive adaptations. To this extent, extensive practice is associated with the development of general and task-specific mental representations, which play an important role in the organization and control of action. Recently, new experimental methods have been developed, which allow for investigating the organization and structure of these representations, along with the functional structure of the movement kinematics. In the current article, we present a new approach for examining the overlap between skill representations and motor output. In doing so, we first present an architecture model, which addresses links between biomechanical and cognitive levels of motor control. Next, we review the state of the art in assessing memory structures underlying complex action. Following we present a new spatio-temporal decomposition method for illuminating the functional structure of movement kinematics, and finally, we apply these methods to investigate the overlap between the structure of motor representations in memory and their corresponding kinematic structures. Our aim is to understand the extent to which the output at a kinematic level is governed by representations at a cognitive level of motor control. PMID:24065915

  3. Tryptophan hydroxylase 2 aggregates through disulfide cross-linking upon oxidation: Possible link to serotonin deficits and non-motor symptoms in Parkinson's disease

    PubMed Central

    Kuhn, Donald M.; Sykes, Catherine E.; Geddes, Timothy J.; Jaunarajs, Karen L. Eskow; Bishop, Christopher

    2010-01-01

    Parkinson's disease (PD) is a progressive neurodegenerative disorder characterized by the loss of dopamine neurons of the nigrostriatal system, resulting in severe motor disturbances. Although much less appreciated, non-motor symptoms are also very common in PD and many can be traced to serotonin neuronal deficits. Tryptophan hydroxylase 2 (TPH2), the rate-limiting enzyme in the serotonin biosynthesis, is a phenotypic marker for serotonin neurons and is known to be extremely labile to oxidation. Therefore, the oxidative processes that prevail in PD could cause TPH2 misfolding and modify 5HT neuronal function much as is seen in dopamine neurons. Oxidation of TPH2 inhibits enzyme activity and leads to the formation of high molecular weight aggregates in a dithiothreitol-reversible manner. Cysteine-scanning mutagenesis shows that as long as a single cysteine residue (out of a total of 13 per monomer) remains in TPH2, it cross-links upon oxidation and only cysteine-less mutants are resistant to this effect. The effects of oxidants on TPH2 catalytic function and cross-linking are also observed in intact TPH2-expressing HEK293 cells. Oxidation shifts TPH2 from the soluble compartment into membrane fractions and large inclusion bodies. Sequential non-reducing/reducing two-dimensional SDS-PAGE and immunoblotting confirmed that TPH2 was one of a small number of cytosolic proteins that form disulfide-bonded aggregates. The propensity of TPH2 to misfold upon oxidation of its cysteine residues is responsible for its catalytic lability and may be related to loss of serotonin neuronal function in PD and the emergence of non-motor (psychiatric) symptoms. PMID:21105877

  4. Astrocytes expressing ALS-linked mutated SOD1 release factors selectively toxic to motor neurons.

    PubMed

    Nagai, Makiko; Re, Diane B; Nagata, Tetsuya; Chalazonitis, Alcmène; Jessell, Thomas M; Wichterle, Hynek; Przedborski, Serge

    2007-05-01

    Mutations in superoxide dismutase-1 (SOD1) cause a form of the fatal paralytic disorder amyotrophic lateral sclerosis (ALS), presumably by a combination of cell-autonomous and non-cell-autonomous processes. Here, we show that expression of mutated human SOD1 in primary mouse spinal motor neurons does not provoke motor neuron degeneration. Conversely, rodent astrocytes expressing mutated SOD1 kill spinal primary and embryonic mouse stem cell-derived motor neurons. This is triggered by soluble toxic factor(s) through a Bax-dependent mechanism. However, mutant astrocytes do not cause the death of spinal GABAergic or dorsal root ganglion neurons or of embryonic stem cell-derived interneurons. In contrast to astrocytes, fibroblasts, microglia, cortical neurons and myocytes expressing mutated SOD1 do not cause overt neurotoxicity. These findings indicate that astrocytes may play a role in the specific degeneration of spinal motor neurons in ALS. Identification of the astrocyte-derived soluble factor(s) may have far-reaching implications for ALS from both a pathogenic and therapeutic standpoint. PMID:17435755

  5. Astrocytes expressing ALS-linked mutated SOD1 release factors selectively toxic to motor neurons

    PubMed Central

    Nagai, Makiko; Re, Diane B; Nagata, Tetsuya; Chalazonitis, Alcmène; Jessell, Thomas M; Wichterle, Hynek; Przedborski, Serge

    2013-01-01

    Mutations in superoxide dismutase-1 (SOD1) cause a form of the fatal paralytic disorder amyotrophic lateral sclerosis (ALS), presumably by a combination of cell-autonomous and non–cell-autonomous processes. Here, we show that expression of mutated human SOD1 in primary mouse spinal motor neurons does not provoke motor neuron degeneration. Conversely, rodent astrocytes expressing mutated SOD1 kill spinal primary and embryonic mouse stem cell–derived motor neurons. This is triggered by soluble toxic factor(s) through a Bax-dependent mechanism. However, mutant astrocytes do not cause the death of spinal GABAergic or dorsal root ganglion neurons or of embryonic stem cell–derived interneurons. In contrast to astrocytes, fibroblasts, microglia, cortical neurons and myocytes expressing mutated SOD1 do not cause overt neurotoxicity. These findings indicate that astrocytes may play a role in the specific degeneration of spinal motor neurons in ALS. Identification of the astrocyte-derived soluble factor(s) may have far-reaching implications for ALS from both a pathogenic and therapeutic standpoint. PMID:17435755

  6. Motor Difficulties in Autism Spectrum Disorder: Linking Symptom Severity and Postural Stability

    ERIC Educational Resources Information Center

    Travers, Brittany G.; Powell, Patrick S.; Klinger, Laura G.; Klinger, Mark R.

    2013-01-01

    Postural stability is a fundamental aspect of motor ability that allows individuals to sustain and maintain the desired physical position of one's body. The present study examined postural stability in average-IQ adolescents and adults with Autism Spectrum Disorder (ASD). Twenty-six individuals with ASD and 26 age-and-IQ-matched individuals…

  7. The NMDA Receptor NR1 C1 Region Bound to Calmodulin: Structural Insights into Functional Differences between Homologous Domains

    SciTech Connect

    Ataman, Zeynep Akyol; Gakhar, Lokesh; Sorensen, Brenda R.; Hell, Johannes W.; Shea, Madeline A.

    2008-09-17

    Calmodulin (CaM) regulates tetrameric N-methyl-D-aspartate receptors (NMDARs) by binding tightly to the C0 and C1 regions of its NR1 subunit. A crystal structure (2HQW; 1.96 {angstrom}) of calcium-saturated CaM bound to NR1C1 (peptide spanning 875-898) showed that NR1 S890, whose phosphorylation regulates membrane localization, was solvent protected, whereas the endoplasmic reticulum retention motif was solvent exposed. NR1 F880 filled the CaM C-domain pocket, whereas T886 was closest to the N-domain pocket. This 1-7 pattern was most similar to that in the CaM-MARCKS complex. Comparison of CaM-ligand wrap-around conformations identified a core tetrad of CaM C-domain residues (FLMM{sub C}) that contacted all ligands consistently. An identical tetrad of N-domain residues (FLMM{sub N}) made variable sets of contacts with ligands. This CaM-NR1C1 structure provides a foundation for designing mutants to test the role of CaM in NR1 trafficking as well as insights into how the homologous CaM domains have different roles in molecular recognition.

  8. Trouble at Tsavo: The Tale of the Black Rhino. BrainLink: Motor Highways.

    ERIC Educational Resources Information Center

    Boyle, Grace

    The BrainLink project offers educational materials that focus on current neuroscience issues with the goal of promoting a deeper understanding of how the nervous system works and why the brain makes each individual special while conveying the excitement of "doing science" among upper elementary and middle school students. Project materials engage…

  9. Collapsin Response Mediator Protein-2 (Crmp2) Regulates Trafficking by Linking Endocytic Regulatory Proteins to Dynein Motors*

    PubMed Central

    Rahajeng, Juliati; Giridharan, Sai S. P.; Naslavsky, Naava; Caplan, Steve

    2010-01-01

    Endocytosis is a conserved cellular process in which nutrients, lipids, and receptors are internalized and transported to early endosomes, where they are sorted and either channeled to degradative pathways or recycled to the plasma membrane. MICAL-L1 and EHD1 are important regulatory proteins that control key endocytic transport steps. However, the precise mechanisms by which they mediate transport, and particularly the mode by which they connect to motor proteins, have remained enigmatic. Here we have identified the collapsin response mediator protein-2 (Crmp2) as an interaction partner of MICAL-L1 in non-neuronal cells. Crmp2 interacts with tubulin dimers and kinesin and negatively regulates dynein-based transport in neuronal cells, but its expression and function in non-neuronal cells have remained poorly characterized. Upon Crmp2 depletion, we observed dramatic relocalization of internalized transferrin (Tf) from peripheral vesicles to the endocytic recycling compartment (ERC), similar to the effect of depleting either MICAL-L1 or EHD1. Moreover, Tf relocalization to the ERC could be inhibited by interfering with microtubule polymerization, consistent with a role for uncoupled motor protein-based transport upon depletion of Crmp2, MICAL-L1, or EHD1. Finally, transfection of dynamitin, a component of the dynactin complex whose overexpression inhibits dynein activity, prevented the relocalization of internalized Tf to the ERC upon depletion of Crmp2, MICAL-L1, or EHD1. These data provide the first trafficking regulatory role for Crmp2 in non-neuronal cells and support a model in which Crmp2 is an important endocytic regulatory protein that links MICAL-L1·EHD1-based vesicular transport to dynein motors. PMID:20801876

  10. AmeriFlux US-NR1 Niwot Ridge Forest (LTER NWT1)

    SciTech Connect

    Blanken, Peter

    2016-01-01

    This is the AmeriFlux version of the carbon flux data for the site US-NR1 Niwot Ridge Forest (LTER NWT1). Site Description - The Niwot Ridge AmeriFlux site is located in a subalpine forest ecosystem just below the Continental Divide near Nederland, CO. The site is located at 3050 m elevation, within 600m of the NOAA C1 long-term monitoring station, approximately 8 km east of the Continental Divide. The surrounding subalpine forest is ~97 years old and in a state of aggradation, having recovered from early twentieth century logging (Monson, et al. Global Change Biology (2002), 8 459-478).

  11. Investigation of Associations between NR1D1, RORA and RORB Genes and Bipolar Disorder

    PubMed Central

    Lai, Yin-Chieh; Kao, Chung-Feng; Lu, Mong-Liang; Chen, Hsi-Chung; Chen, Po-Yu; Chen, Chien-Hsiun; Shen, Winston W.; Wu, Jer-Yuarn; Lu, Ru-Band; Kuo, Po-Hsiu

    2015-01-01

    Several genes that are involved in the regulation of circadian rhythms are implicated in the susceptibility to bipolar disorder (BD). The current study aimed to investigate the relationships between genetic variants in NR1D1 RORA, and RORB genes and BD in the Han Chinese population. We conducted a case-control genetic association study with two samples of BD patients and healthy controls. Sample I consisted of 280 BD patients and 200 controls. Sample II consisted of 448 BD patients and 1770 healthy controls. 27 single nucleotide polymorphisms in the NR1D1, RORA, and RORB genes were genotyped using GoldenGate VeraCode assays in sample I, and 492 markers in the three genes were genotyped using Affymetrix Genome-Wide CHB Array in sample II. Single marker and gene-based association analyses were performed using PLINK. A combined p-value for the joining effects of all markers within a gene was calculated using the rank truncated product method. Multifactor dimensionality reduction (MDR) method was also applied to test gene-gene interactions in sample I. All markers were in Hardy-Weinberg equilibrium (P>0.001). In sample I, the associations with BD were observed for rs4774388 in RORA (OR = 1.53, empirical p-value, P = 0.024), and rs1327836 in RORB (OR = 1.75, P = 0.003). In Sample II, there were 45 SNPs showed associations with BD, and the most significant marker in RORA was rs11639084 (OR = 0.69, P = 0.002), and in RORB was rs17611535 (OR = 3.15, P = 0.027). A combined p-value of 1.6×10−6, 0.7, and 1.0 was obtained for RORA, RORB and NR1D1, respectively, indicting a strong association for RORA with the risk of developing BD. A four way interaction was found among markers in NR1D1, RORA, and RORB with the testing accuracy 53.25% and a cross-validation consistency of 8 out of 10. In sample II, 45 markers had empirical p-values less than 0.05. The most significant markers in RORA and RORB genes were rs11639084 (OR = 0.69, P = 0.002), and rs17611535 (OR = 3.15, P = 0

  12. Retention of NMDA receptor NR2 subunits in the lumen of endoplasmic reticulum in targeted NR1 knockout mice

    PubMed Central

    Fukaya, Masahiro; Kato, Akira; Lovett, Chanel; Tonegawa, Susumu; Watanabe, Masahiko

    2003-01-01

    Glutamate is a major excitatory neurotransmitter in the mammalian central nervous system, and the N-methyl-d-aspartate-selective glutamate receptor (NR) consisting of the NR1 subunit and an NR2 or NR3 subunit plays crucial roles in synaptic transmission, plasticity, and learning and memory. By using a knockout mouse strain, in which the NR1 gene deletion is primarily targeted to the CA1 pyramidal cells of the hippocampus, we investigated the in vivo effect of the loss of the NR1 subunit on the cellular expression and intracellular distribution of the NR2 subunits. The NR1 gene deletion had no apparent effect on the levels of NR2A or NR2B mRNA but led to severe reductions of NR2A and NR2B protein in dendrites of CA1 pyramidal cells. This reduced dendritic distribution of the NR2 subunits accompanied their robust accumulation in perikarya, where they were condensed in the lumen of the endoplasmic reticulum as electron-dense granules. These granules were also observed in CA1 pyramidal cells of the control mice but they were much fewer and contained no detectable levels of the NR2 subunit. The effect of the NR1 knockout on intracellular localization of the NR2 subunits was specific in that no such effect was observed for the GluR1 and PSD-95, two other major postsynaptic proteins. These results suggest that the NR1 subunit plays a crucial role in the release of the NR2 subunit from the endoplasmic reticulum in hippocampal pyramidal cells in vivo, and when the NR1 subunit is unavailable, the NR2 subunits are retained and aggregate into intracisternal granules. PMID:12676993

  13. Calcium dysregulation links ALS defective proteins and motor neuron selective vulnerability

    PubMed Central

    Leal, Sónia S.; Gomes, Cláudio M.

    2015-01-01

    More than 20 distinct gene loci have so far been implicated in amyotrophic lateral sclerosis (ALS), a fatal neurodegenerative disorder characterized by progressive neurodegeneration of motor neurons (MN) and death. Most of this distinct set of ALS-related proteins undergoes toxic deposition specifically in MN for reasons which remain unclear. Here we overview a recent body of evidence indicative that mutations in ALS-related proteins can disrupt fundamental Ca2+ signalling pathways in MN, and that Ca2+ itself impacts both directly or indirectly in many ALS critical proteins and cellular processes that result in MN neurodegeneration. We argue that the inherent vulnerability of MN to dysregulation of intracellular Ca2+ is deeply associated with discriminating pathogenicity and aberrant crosstalk of most of the critical proteins involved in ALS. Overall, Ca2+ deregulation in MN is at the cornerstone of different ALS processes and is likely one of the factors contributing to the selective susceptibility of these cells to this particular neurodegenerative disease. PMID:26136661

  14. Linking motor-related brain potentials and velocity profiles in multi-joint arm reaching movements.

    PubMed

    Amengual, Julià L; Marco-Pallarés, Josep; Grau, Carles; Münte, Thomas F; Rodríguez-Fornells, Antoni

    2014-01-01

    The study of the movement related brain potentials (MRPBs) needs accurate technical approaches to disentangle the specific patterns of bran activity during the preparation and execution of movements. During the last forty years, synchronizing the electromyographic activation (EMG) of the muscle with electrophysiological recordings (EEG) has been commonly ussed for these purposes. However, new clinical approaches in the study of motor diseases and rehabilitation suggest the demand of new paradigms that might go further into the study of the brain activity associated with the kinematics of movements. As a response to this call, we have used a 3-D hand-tracking system with the aim to record continuously the position of an ultrasonic sender attached to the hand during the performance of multi-joint self-paced movements. We synchronized time-series of position and velocity of the sender with the EEG recordings, obtaining specific patterns of brain activity as a function of the fluctuations of the kinematics during natural movement performance. Additionally, the distribution of the brain activity during the preparation and execution phases of movements was similar that reported previously using the EMG, suggesting the validity of our technique. We claim that this paradigm could be usable in patients because of its simplicity and the potential knowledge that can be extracted from clinical protocols. PMID:24808853

  15. The link between texting and motor vehicle collision frequency in the orthopaedic trauma population

    PubMed Central

    Issar, Neil M.; Kadakia, Rishin J.; Tsahakis, James M.; Yoneda, Zachary T.; Sethi, Manish K.; Mir, Hassan R.; Archer, Kristin; Obremskey, William T.; Jahangir, Amir A.

    2013-01-01

    Abstract: Background: This study will evaluate whether or not texting frequency while driving and/or texting frequency in general are associated with an increased risk of incurring a motor vehicle collision (MVC) resulting in orthopaedic trauma injuries. Methods: All patients who presented to the Vanderbilt University Medical Center Orthopaedic Trauma Clinic were administered a questionnaire to determine background information, mean phone use, texting frequency, texting frequency while driving, and whether or not the injury was the result of an MVC in which the patient was driving. Results: 237 questionnaires were collected. 60 were excluded due to incomplete date, leaving 57 questionnaires in the MVC group and 120 from patients with non-MVC injuries. Patients who sent more than 30 texts per week (“heavy texters”) were 2.22 times more likely to be involved in an MVC than those who texted less frequently. 84% of respondents claimed to never text while driving. Dividing the sample into subsets on the basis of age (25 years of age or below considered “young adult,” and above 25 years of age considered “adult”),young, heavy texters were 6.76 times more likely to be involved in an MVC than adult non-heavy texters (p = 0.000). Similarly, young adult, non-heavy texters were 6.65 (p = 0.005) times more likely to be involved in an MVC, and adult, heavy texters were 1.72 (p = 0.186) times more likely to be involved in an MVC. Conclusions: Patients injured in an MVC sent more text messages per week than non-MVC patients. Additionally, controlling for age demonstrated that young age and heavy general texting frequency combined had the highest increase in MVC risk, with the former being the variable of greatest effect. PMID:23416747

  16. Experimental study of a bidirectional DC-DC converter for the DC link voltage control and the regenerative braking in PM motor drives devoted to electrical vehicles

    SciTech Connect

    Caricchi, F.; Crescimbini, F.; Noia, G.; Pirolo, D.

    1994-12-31

    The use of a bidirectional DC-DC converter operating in the DC link of CRPWM-inverter-fed motor drives devoted to electric vehicles (EVs) application allows a suitable control of both motoring and regenerative braking operations, and it can contribute to a significant increase of the motor drive overall efficiency. This paper deals with the experimental study of a bidirectional DC-DC converter prototype which has been designed for application in small-size EVs propelled by axial-flux PM motor drives. The paper discusses the converter modes of operation and reports the experimental results taken from a converter prototype which has been constructed using an IGBTs power module rated 600 V, 50 A. 2 refs.

  17. Expression of NR1I3 in mouse lung tumors induced by the tobacco-specific nitrosamine 4-(methylnitrosamino)-4-(3-pyridyl)-1-butanone

    PubMed Central

    Fukumasu, H.; Cordeiro, Y.G.; Rochetti, A.L.; Barra, C.N.; Sámora, T.S.; Strefezzi, R.F.; Dagli, M.L.Z.

    2015-01-01

    Nuclear receptor subfamily 1, group I, member 3 (NR1I3) is reported to be a possible novel therapeutic target for some cancers, including lung, brain and hematopoietic tumors. Here, we characterized expression of NR1I3 in a mouse model of lung carcinogenesis induced by 4-(methylnitrosamino)-4-(3-pyridyl)-1-butanone (NNK), the most potent tobacco carcinogen. Lung tumors were collected from mice treated with NNK (400 mg/kg) and euthanized after 52 weeks. Benign and malignant lesions were formalin-fixed and paraffin-embedded for histology and immunohistochemistry, with samples snap-frozen for mRNA analysis. Immunohistochemically, we found that most macrophages and type I and II pneumocytes expressed NR1I3, whereas fibroblasts and endothelial cells were NR1I3−. Compared with benign lesions, malignant lesions had less NR1I3+ tumor cells. Gene expression analysis also showed an inverse correlation between NR1I3 mRNA expression and tumor size (P=0.0061), suggesting that bigger tumors expressed less NR1I3 transcripts, in accordance with our immunohistochemical NR1I3 tests. Our results indicate that NR1I3 expression decreased during progression of malignant lung tumors induced by NNK in mice. PMID:25714878

  18. Aquatic studies at the 100-HR-3 and 100-NR-1 operable units

    SciTech Connect

    Cushing, C.E.

    1993-04-01

    Pacific Northwest Laboratory initiated a program to characterize selected aquatic biological populations to determine (1) existing levels of inorganic chemical and radionuclide contamination, and (2) the populations' suitability as indicators of chemical releases during cleanup activities at the US Department of Energy's Hanford Site. Following work plans for the ground-water operable units, lower trophic levels in the aquatic habitat (periphyton and caddisfly larvae) were evaluated for contaminants at the 100-HR-3 Operable Unit and 100-NR-1 Operable Unit. The results were evaluated to determine the need for further sampling. If the results showed no significant contamination compared to upriver levels, sampling would be discontinued. The periphyton community appears to be suitable for determining contamination levels. Baseline concentrations for stable chromium were established and will be useful for comparing samples collected when contaminant release is expected. Concentrations of [sup 60]Co, [sup 90]Sr, and [sup 137]Cs in periphyton were essentially below detectable limits, which will also make this community useful in detecting potential releases of radionuclides during cleanup activities. Levels for both stable chromium and radionuclides were essentially below detection limits for caddisfly larvae. Thus, these organisms may be used to monitor suspected contaminant releases from cleanup activities; if concentrations exceed detection limits, they may be related to these activities. Two candidate threatened and endangered species of molluscs occur in the Hanford Reach of the Columbia River. These are the shortface lanx (Fisherola nuttalli), which is a Washington State candidate species, and the Columbia pebblesnail (Fluminicola columbiana), which is both a state and federal candidate species. Specimens of the shortface lanx were observed in the vicinity of N Springs (100-NR-1 Operable Unit); they likely occur throughout this area.

  19. Aquatic studies at the 100-HR-3 and 100-NR-1 operable units

    SciTech Connect

    Cushing, C.E.

    1993-04-01

    Pacific Northwest Laboratory initiated a program to characterize selected aquatic biological populations to determine (1) existing levels of inorganic chemical and radionuclide contamination, and (2) the populations` suitability as indicators of chemical releases during cleanup activities at the US Department of Energy`s Hanford Site. Following work plans for the ground-water operable units, lower trophic levels in the aquatic habitat (periphyton and caddisfly larvae) were evaluated for contaminants at the 100-HR-3 Operable Unit and 100-NR-1 Operable Unit. The results were evaluated to determine the need for further sampling. If the results showed no significant contamination compared to upriver levels, sampling would be discontinued. The periphyton community appears to be suitable for determining contamination levels. Baseline concentrations for stable chromium were established and will be useful for comparing samples collected when contaminant release is expected. Concentrations of {sup 60}Co, {sup 90}Sr, and {sup 137}Cs in periphyton were essentially below detectable limits, which will also make this community useful in detecting potential releases of radionuclides during cleanup activities. Levels for both stable chromium and radionuclides were essentially below detection limits for caddisfly larvae. Thus, these organisms may be used to monitor suspected contaminant releases from cleanup activities; if concentrations exceed detection limits, they may be related to these activities. Two candidate threatened and endangered species of molluscs occur in the Hanford Reach of the Columbia River. These are the shortface lanx (Fisherola nuttalli), which is a Washington State candidate species, and the Columbia pebblesnail (Fluminicola columbiana), which is both a state and federal candidate species. Specimens of the shortface lanx were observed in the vicinity of N Springs (100-NR-1 Operable Unit); they likely occur throughout this area.

  20. A mollusk VDR/PXR/CAR-like (NR1J) nuclear receptor provides insight into ancient detoxification mechanisms.

    PubMed

    Cruzeiro, Catarina; Lopes-Marques, Mónica; Ruivo, Raquel; Rodrigues-Oliveira, Nádia; Santos, Miguel M; Rocha, Maria João; Rocha, Eduardo; Castro, L Filipe C

    2016-05-01

    The origin and diversification of the metazoan endocrine systems represents a fundamental research issue in biology. Nuclear receptors are critical components of these systems. A particular group named VDR/PXR/CAR (NR1I/J) is central in the mediation of detoxification responses. While orthologues have been thoroughly characterized in vertebrates, a sparse representation is currently available for invertebrates. Here, we provide the first isolation and characterization of a lophotrochozoan protostome VDR/PXR/CAR nuclear receptor (NR1J), in the estuarine bivalve the peppery furrow shell (Scrobicularia plana). Using a reporter gene assay, we evaluated the xenobiotic receptor plasticity comparing the human PXR with the S. plana NR1Jβ. Our results show that the molluscan receptor responds to a natural toxin (okadaic acid) in a similar fashion to that reported for other invertebrates. In contrast, the pesticide esfenvalerate displayed a unique response, since it down regulated transactivation at higher concentrations, while for triclosan no response was observed. Additionally, we uncovered lineage specific gene duplications and gene loss in the gene group encoding NRs in protostomes with likely impacts on the complexity of detoxification mechanisms across different phyla. Our findings pave the way for the development of multi-specific sensor tools to screen xenobiotic compounds acting via the NR1I/J group. PMID:26921727

  1. Shape-Conserved Dynamic Condensation in the Process of Aster Formation from a System of Microtubules and Cross-Linked Kinesin Motors

    NASA Astrophysics Data System (ADS)

    Kim, K.; Sikora, A.; Nakazawa, H.; Umetsu, M.; Hwang, W.; Teizer, W.

    2015-03-01

    We report fluorescence microscopy studies of a cellular element-based active system that is composed of rhodamine-labeled microtubules and functionalized kinesin motor proteins, cross-linked via streptavidin-coated quantum dots. The motor proteins organize microtubules into aster-like structures containing core aggregations of the quantum dot-motor protein complexes. The cores result from the dynamic condensation of sub-clusters that are connected to each other randomly. The inter-cluster distance decays exponentially with time during the condensation. Intriguingly, the shape defined by lines connecting the clusters is well conserved while the dynamic process reduces the size. This shape conservation is governed by a scaling behavior during the condensation, following a power law with respect to the distance between sub-clusters. We explain this isomorphic contraction during the aster formation process using a simple mechanistic model.

  2. The HR97 (NR1L) group of nuclear receptors: a new group of nuclear receptors discovered in Daphnia species.

    PubMed

    Li, Yangchun; Ginjupalli, Gautam K; Baldwin, William S

    2014-09-15

    The recently sequenced Daphnia pulex genome revealed the NR1L nuclear receptor group consisting of three novel receptors. Phylogenetic studies show that this group is related to the NR1I group (CAR/PXR/VDR) and the NR1J group (HR96), and were subsequently named HR97a/b/g. Each of the HR97 paralogs from Daphnia magna, a commonly used crustacean in toxicity testing, was cloned, sequenced, and partially characterized. Phylogenetic analysis indicates that the HR97 receptors are present in primitive arthropods such as the chelicerates but lost in insects. qPCR and immunohistochemistry demonstrate that each of the receptors is expressed near or at reproductive maturity, and that HR97g, the most ancient of the HR97 receptors, is primarily expressed in the gastrointestinal tract, mandibular region, and ovaries, consistent with a role in reproduction. Transactivation assays using an HR97a/b/g-GAL4 chimera indicate that unlike Daphnia HR96 that is promiscuous with respect to ligand recognition, the HR97 receptors do not respond to many of the ligands that activate CAR/PXR/HR96 nuclear receptors. Only three putative ligands of HR97 receptors were identified in this study: pyriproxyfen, methyl farnesoate, and arachidonic acid. Only arachidonic acid, which acts as an inverse agonist, alters HR97g activity at concentrations that would be considered within physiologically relevant ranges. Overall, this study demonstrates that, although closely related to the promiscuous receptors in the NR1I and NR1J groups, the HR97 receptors are mostly likely not multi-xenobiotic sensors, but rather may perform physiological functions, potentially in reproduction, unique to crustaceans and other non-insect arthropod groups. PMID:25092536

  3. The N-terminal domains of both NR1 and NR2 subunits determine allosteric Zn2+ inhibition and glycine affinity of N-methyl-D-aspartate receptors.

    PubMed

    Madry, Christian; Mesic, Ivana; Betz, Heinrich; Laube, Bodo

    2007-12-01

    The N-methyl-D-aspartate (NMDA) subtype of ionotropic glutamate receptors (iGluRs) is a tetrameric protein composed of homologous NR1 and NR2 subunits, which require the binding of glycine and glutamate, respectively, for efficient channel gating. The extracellular N-terminal domains (NTDs) of iGluR subunits show sequence homology to the bacterial periplasmic leucine/isoleucine/valine binding protein (LIVBP) and have been implicated in iGluR assembly, trafficking, and function. Here, we investigated how deletion of the NR1- and NR2-NTDs affects the expression and function of NMDA receptors. Both proteolytic cleavage of the NR1-NTD from assembled NR1/NR2 receptors and coexpression of the NTD-deleted NR1 subunit with wild-type or NTD-deleted NR2 subunits resulted in agonist-gated channels that closely resembled wild-type receptors. This indicates that the NTDs of both NMDA receptor subunits are not essential for receptor assembly and function. However, deletion of either the NR1 or the NR2 NTD eliminated high-affinity, allosteric inhibition of agonist-induced currents by Zn2+ and ifenprodil, consistent with the idea that interdomain interactions between these domains are important for allosteric receptor modulation. Furthermore, by replacing the NR2A-NTD with the NR2B NTD, and vice versa, the different glycine affinities of NR1/NR2A and NR1/NR2B receptors were found to be determined by their respective NR2-NTDs. Together, these data show that the NTDs of both the NR1 and NR2 subunits determine allosteric inhibition and glycine potency but are not required for NMDA receptor assembly. PMID:17878266

  4. ALS-linked TDP-43 mutations produce aberrant RNA splicing and adult-onset motor neuron disease without aggregation or loss of nuclear TDP-43.

    PubMed

    Arnold, Eveline S; Ling, Shuo-Chien; Huelga, Stephanie C; Lagier-Tourenne, Clotilde; Polymenidou, Magdalini; Ditsworth, Dara; Kordasiewicz, Holly B; McAlonis-Downes, Melissa; Platoshyn, Oleksandr; Parone, Philippe A; Da Cruz, Sandrine; Clutario, Kevin M; Swing, Debbie; Tessarollo, Lino; Marsala, Martin; Shaw, Christopher E; Yeo, Gene W; Cleveland, Don W

    2013-02-19

    Transactivating response region DNA binding protein (TDP-43) is the major protein component of ubiquitinated inclusions found in amyotrophic lateral sclerosis (ALS) and frontotemporal lobar degeneration (FTLD) with ubiquitinated inclusions. Two ALS-causing mutants (TDP-43(Q331K) and TDP-43(M337V)), but not wild-type human TDP-43, are shown here to provoke age-dependent, mutant-dependent, progressive motor axon degeneration and motor neuron death when expressed in mice at levels and in a cell type-selective pattern similar to endogenous TDP-43. Mutant TDP-43-dependent degeneration of lower motor neurons occurs without: (i) loss of TDP-43 from the corresponding nuclei, (ii) accumulation of TDP-43 aggregates, and (iii) accumulation of insoluble TDP-43. Computational analysis using splicing-sensitive microarrays demonstrates alterations of endogenous TDP-43-dependent alternative splicing events conferred by both human wild-type and mutant TDP-43(Q331K), but with high levels of mutant TDP-43 preferentially enhancing exon exclusion of some target pre-mRNAs affecting genes involved in neurological transmission and function. Comparison with splicing alterations following TDP-43 depletion demonstrates that TDP-43(Q331K) enhances normal TDP-43 splicing function for some RNA targets but loss-of-function for others. Thus, adult-onset motor neuron disease does not require aggregation or loss of nuclear TDP-43, with ALS-linked mutants producing loss and gain of splicing function of selected RNA targets at an early disease stage. PMID:23382207

  5. High resolution melting analysis of the NR1I3 genetic variants: Is there an association with neonatal hyperbilirubinemia?

    PubMed

    Cheung, Tian Pei; Van Rostenberghe, Hans; Ismail, Rosliza; Nawawi, Noor Namirah; Abdullah, Nurul Amierah; Ramli, Noraida; Ibrahim, Nor Rosidah; Hj Abd Majid, Noorizan; Mohd Yusoff, Narazah; Nishio, Hisahide; Yusoff, Surini

    2015-12-01

    Constitutive androstane receptor (CAR) encoded by the nuclear receptor subfamily 1, group I, member 3 (NR1I3) gene regulates the elimination of bilirubin through activating the components of the bilirubin clearance pathway. Hence, NR1I3 genetic variants may affect bilirubin metabolism and result in neonatal hyperbilirubinemia. Thus far, research which investigates the association between NR1I3 variants and neonatal hyperbilirubinemia has not been undertaken in any population. The present study aimed to evaluate the influence of MPJ6_1I3008 (rs10157822), IVS8+116T>G (rs4073054) and 540A>G (rs2307424) on neonatal hyperbilirubinemia development in the Malay population. Buccal swabs were collected from 232 hyperbilirubinemia and 277 control term newborns with gestational age ≥37weeks and birth weight ≥2500g. The NR1I3 variants were genotyped by using high resolution melting (HRM) assays and verified by DNA sequencing. Gender, mode of delivery and birth weight did not differ between hyperbilirubinemia and control groups. The genotypic and allelic frequencies of MPJ6_1I3008, IVS8+116T>G and 540A>G were not significantly different between the groups. However, stratification by gender revealed a significant inverse association between homozygous variant genotype of MPJ6_1I3008 and risk of neonatal hyperbilirubinemia in the females (OR, 0.44; 95% CI, 0.20-0.95; p=0.034). This study demonstrates that the homozygous variant genotype of MPJ6_1I3008 was associated with a significant reduced risk of neonatal hyperbilirubinemia in the females. PMID:26188155

  6. A reconsideration of the link between the energetics of water and of ATP hydrolysis energy in the power strokes of molecular motors in protein structures.

    PubMed

    Widdas, Wilfred F

    2008-09-01

    Mechanical energy from oxygen metabolism by mammalian tissues has been studied since 1837. The production of heat by mechanical work was studied by Fick in about 1860. Prior to Fick's work, energetics were revised by Joule's experiments which founded the First Law of Thermodynamics. Fenn in 1923/24 found that frog muscle contractions generated extra heat proportional to the amount of work done in shortening the muscle. This was fully consistent with the Joule, Helmholtz concept used for the First Law of Thermodynamics. The link between the energetics of water and ATP hydrolysis in molecular motors is recommended for reconsideration. PMID:19325829

  7. A Reconsideration of the Link between the Energetics of Water and of ATP Hydrolysis Energy in the Power Strokes of Molecular Motors in Protein Structures

    PubMed Central

    Widdas, Wilfred F.

    2008-01-01

    Mechanical energy from oxygen metabolism by mammalian tissues has been studied since 1837. The production of heat by mechanical work was studied by Fick in about 1860. Prior to Fick’s work, energetics were revised by Joule’s experiments which founded the First Law of Thermodynamics. Fenn in 1923/24 found that frog muscle contractions generated extra heat proportional to the amount of work done in shortening the muscle. This was fully consistent with the Joule, Helmholtz concept used for the First Law of Thermodynamics. The link between the energetics of water and ATP hydrolysis in molecular motors is recommended for reconsideration. PMID:19325829

  8. Metagenomics of Water Column Microbes Near Brine Pool NR1 and adjacent regions of the Northern Gulf of Mexico Collected in Fall 2009

    NASA Astrophysics Data System (ADS)

    Wood, A. M.; Goodwin, K. D.; Brami, D.; Schwartz, A.; Toledo, G.

    2012-12-01

    High-throughput sequencing was applied to eight water column samples collected from the Gulf of Mexico in 2009 in regions SW and west of the 2010 Macondo oil spill. Samples were collected by Niskin-equipped CTD (~200 and ~650 m depths) at two locations, including a site over a methane brine pool (Brine Pool NR1). In addition, seawater was collected ~3m lateral of the pool (649m depth) via Niskin bottle equipped on the Johnson-Sea-Link submersible. Unassembled reads were submitted to the Synthetic Genomics bioinformatics pipeline for taxonomic analysis. The distribution of Bacteria (56-73%), Archae (7-16%), Eukaryotes (12-23%), and unclassified sequences (6-10%) were similar for all samples. However, certain taxonomic classifications were relatively more abundant in deeper samples, and differences were noted for samples collected by submersible. For example, Methylophaga was classified as 38% of the order Thiotrichales for the Niskin/submersible sample compared to 0% in the 200m-depth samples and 3-11% in the 650m samples. Methylophaga is a genus of indigenous methylotrophs reported to respond during the Deepwater Horizon event of 2010. In contrast, sequence abundance for Oceanospirillales, also reported to respond during the event, was similar for all samples (6-9% of the gamma-proteobacteria).

  9. Role of NR1I2 (pregnane X receptor) polymorphisms in head and neck squamous cell carcinoma.

    PubMed

    Reuter, Tasmin; Warta, Rolf; Theile, Dirk; Meid, Andreas D; Rigalli, Juan Pablo; Mogler, Carolin; Herpel, Esther; Grabe, Niels; Lahrmann, Bernd; Plinkert, Peter K; Herold-Mende, Christel; Dyckhoff, Gerhard; Haefeli, Walter Emil; Weiss, Johanna

    2015-11-01

    The pregnane X receptor (PXR) is a transcription factor regulating genes involved not only in pharmacokinetics but also in chemotherapy resistance and cancer progression. The significance of PXR for survival of head and neck squamous cell carcinoma (HNSCC) patients is unknown so far. Single nucleotide polymorphisms (SNPs) in the PXR-encoding NR1I2 gene influence receptor functionality and inducibility by ligands and thus modulate expression and activity of its target genes. In this study, seven SNPs in the NR1I2 gene were investigated for an association with PXR protein expression and survival of HNSCC patients. Genotyping was conducted using hybridisation probe format methodology. PXR protein expression was quantified by immunohistochemistry of tissue microarray samples of HNSCC biopsies. Genotypes were correlated to PXR protein expression by a linear model regressing on the continuous gene expression value and a Cox model regressing on overall survival times. Haplotype analysis was performed by reconstruction of haplotypes from genotype information according to the expectation-maximisation algorithm. Of all tested SNPs, rs1054190 and rs1054191 allele variants tended to correlate with a reduced protein expression score of PXR (p = 0.088). Four haplotypes, each consisting of two SNPs, rs3814055/rs1054190 and rs3814055/rs1054191 as well as rs1523127/rs1054190 and rs1523127/rs1054191, showed a significant reduction of the PXR expression score (p = 0.049 and p = 0.032). However, neither allele variants nor haplotypes influenced overall survival of the respective patients. Certain NR1I2 SNPs showed an impact on PXR protein expression in HNSCC but did not influence overall survival times, questioning their value as prognostic biomarkers. PMID:26141049

  10. Postsynaptic density levels of the NMDA receptor NR1 subunit and PSD-95 protein in prefrontal cortex from people with schizophrenia

    PubMed Central

    Catts, Vibeke Sørensen; Derminio, Dominique Suzanne; Hahn, Chang-Gyu; Weickert, Cynthia Shannon

    2015-01-01

    Background: There is converging evidence of involvement of N-methyl-d-aspartate (NMDA) receptor hypofunction in the pathophysiology of schizophrenia. Our group recently identified a decrease in total NR1 mRNA and protein expression in the dorsolateral prefrontal cortex in a case-control study of individuals with schizophrenia (n=37/group). The NR1 subunit is critical to NMDA receptor function at the postsynaptic density, a cellular structure rich in the scaffolding protein, PSD-95. The extent to which the NMDA receptor NR1 subunit is altered at the site of action, in the postsynaptic density, is not clear. Aims: To extend our previous results by measuring levels of NR1 and PSD-95 protein in postsynaptic density-enriched fractions of prefrontal cortex from the same individuals in the case-control study noted above. Methods: Postsynaptic density-enriched fractions were isolated from fresh-frozen prefrontal cortex (BA10) and subjected to western blot analysis for NR1 and PSD-95. Results: We found a 20% decrease in NR1 protein (t(66)=−2.874, P=0.006) and a 30% decrease in PSD-95 protein (t(63)=−2.668, P=0.010) in postsynaptic density-enriched fractions from individuals with schizophrenia relative to unaffected controls. Conclusions: Individuals with schizophrenia have less NR1 protein, and therefore potentially fewer functional NMDA receptors, at the postsynaptic density. The associated decrease in PSD-95 protein at the postsynaptic density suggests that not only are glutamate receptors compromised in individuals with schizophrenia, but the overall spine architecture and downstream signaling supported by PSD-95 may also be deficient. PMID:27336043

  11. Breaking The Link Between Legal Access To Alcohol And Motor Vehicle Accidents: Evidence From New South Wales.

    PubMed

    Lindo, Jason M; Siminski, Peter; Yerokhin, Oleg

    2016-07-01

    A large literature has documented significant public health benefits associated with the minimum legal drinking age in the USA, particularly because of the resulting effects on motor vehicle accidents. These benefits form the primary basis for continued efforts to restrict youth access to alcohol. It is important to keep in mind that policymakers have a wide variety of alcohol-control options available to them, and understanding how these policies may complement or substitute for one another can improve policy making moving forward. Towards this end, we propose that investigating the causal effects of the minimum legal drinking age in New South Wales, Australia, provides a particularly informative case study, because Australian states are among the world leaders in their efforts against drunk driving. Using an age-based regression discontinuity design applied to restricted-use data from several sources, we find no evidence that legal access to alcohol has effects on motor vehicle accidents of any type in New South Wales, despite having large effects on drinking and on hospitalizations due to alcohol abuse. Copyright © 2015 John Wiley & Sons, Ltd. PMID:26095332

  12. Differential contribution of the NR1- and NR2A-subunits to the selectivity filter of recombinant NMDA receptor channels.

    PubMed Central

    Wollmuth, L P; Kuner, T; Seeburg, P H; Sakmann, B

    1996-01-01

    1. The molecular determinants for the narrow constriction of recombinant N-methyl-D-aspartate (NMDA) receptor channels composed of wild-type and mutant NR1- and NR2A-subunits were studied in Xenopus oocytes. 2. The relative permeability of differently sized organic cations was used as an indicator of the size of the narrow constriction. From measured reversal potentials under bi-ionic conditions with K+ as the reference solution, permeability ratios were calculated with the Lewis equation. 3. For wild-type NMDA receptor channels, five organic cations showed clear reversal potentials, with permeability ratios (PX/PK): ammonium, 1.28; methylammonium, 0.48; dimethylammonium (DMA), 0.20; diethylammonium, 0.07; and dimethylethanol-ammonium, 0.02. 4. Mutation of the N-site asparagine (N) to glutamine (Q) at homologous positions in either NR1 (position 598) or NR2A (position 595) increased the permeability of DMA relative to wild-type channels about equally. However, for larger sized organic cations, the NR1(N598Q) mutation had stronger effects on increasing their permeability whereas the NR2A(N595Q) mutation was without effect. These changes in organic cation permeability suggest that the NR1(N598Q) mutation increases the pore size while the NR2A(N595Q) mutation does not. 5. Channels in which the NR1 N-site asparagine was replaced by the smaller glycine (G), NR1(N598G)-NR2A, showed the largest increase in pore size of all sites examined in either subunit. In contrast, in the NR2A-subunit the same N-site substitution to glycine produced only small effects on pore size. 6. For the NR2A-subunit, an asparagine residue (position 596) on the C-terminal side of the N-site, when mutated to larger or smaller sized amino acids, produced large, volume-specific effects on pore size. The mutant channel NR1-NR2A(N596G) had the largest increase in pore size of all sites examined in the NR2A-subunit. In contrast, mutation of the homologous position in the NR1-subunit had no effect on

  13. Motor dysfunction in the tottering mouse is linked to cerebellar spontaneous low frequency oscillations revealed by flavoprotein autofluorescence optical imaging

    NASA Astrophysics Data System (ADS)

    Chen, Gang; Popa, Laurentiu S.; Wang, Xinming; Gao, Wangcai; Barnes, Justin; Hendrix, Claudia M.; Hess, Ellen J.; Ebner, Timothy J.

    2009-02-01

    Flavoprotein autofluorescence optical imaging is developing into a powerful research tool to study neural activity, particularly in vivo. In this study we used this imaging technique to investigate the neuronal mechanism underlying the episodic movement disorder that is characteristic of the tottering (tg) mouse, a model of episodic ataxia type 2. Both EA2 and the tg mouse are caused by mutations in the gene encoding Cav2.1 (P/Q-type) voltage-gated Ca2+ channels. These mutations result in a reduction in P/Q Ca2+ channel function. Both EA2 patients and tg mice have a characteristic phenotype consisting of transient motor attacks triggered by stress, caffeine or ethanol. The neural events underlying these episodes of dystonia are unknown. Flavoprotein autofluorescence optical imaging revealed spontaneous, transient, low frequency oscillations in the cerebellar cortex of the tg mouse. Lasting from 30 - 120 minutes, the oscillations originate in one area then spread to surrounding regions over 30 - 60 minutes. The oscillations are reduced by removing extracellular Ca2+ and blocking Cav 1.2/1.3 (L-type) Ca2+ channels. The oscillations are not affected by blocking AMPA receptors or by electrical stimulation of the parallel fiber - Purkinje cell circuit, suggesting the oscillations are generated intrinsically in the cerebellar cortex. Conversely, L-type Ca2+ agonists generate oscillations with similar properties. In the awake tg mouse, transcranial flavoprotein imaging revealed low frequency oscillations that are accentuated during caffeine induced attacks of dystonia. The oscillations increase during the attacks of dystonia and are coupled to oscillations in face and hindlimb EMG activity. These transient oscillations and the associated cerebellar dysfunction provide a novel mechanism by which an ion channel disorder results in episodic motor dysfunction.

  14. Study of the generator/motor operation of induction machines in a high frequency link space power system

    NASA Technical Reports Server (NTRS)

    Lipo, Thomas A.; Sood, Pradeep K.

    1987-01-01

    Static power conversion systems have traditionally utilized dc current or voltage source links for converting power from one ac or dc form to another since it readily achieves the temporary energy storage required to decouple the input from the output. Such links, however, result in bulky dc capacitors and/or inductors and lead to relatively high losses in the converters due to stresses on the semiconductor switches. The feasibility of utilizing a high frequency sinusoidal voltage link to accomplish the energy storage and decoupling function is examined. In particular, a type of resonant six pulse bridge interface converter is proposed which utilizes zero voltage switching principles to minimize switching losses and uses an easy to implement technique for pulse density modulation to control the amplitude, frequency, and the waveshape of the synthesized low frequency voltage or current. Adaptation of the proposed topology for power conversion to single-phase ac and dc voltage or current outputs is shown to be straight forward. The feasibility of the proposed power circuit and control technique for both active and passive loads are verified by means of simulation and experiment.

  15. Elasticity of a semiflexible filament with a discontinuous tension due to a cross-link or a molecular motor

    NASA Astrophysics Data System (ADS)

    Razbin, Mohammadhosein; Benetatos, Panayotis; Zippelius, Annette

    2016-05-01

    We analyze the stretching elasticity of a wormlike chain with a tension discontinuity resulting from a Hookean spring connecting its backbone to a fixed point. The elasticity of isolated semiflexible filaments has been the subject in a significant body of literature, primarily because of its relevance to the mechanics of biological matter. In real systems, however, these filaments are usually part of supramolecular structures involving cross-linkers or molecular motors, which cause tension discontinuities. Our model is intended as a minimal structural element incorporating such a discontinuity. We obtain analytical results in the weakly bending limit of the filament, concerning its force-extension relation and the response of the two parts in which the filament is divided by the spring. For a small tension discontinuity, the linear response of the filament extension to this discontinuity strongly depends on the external tension. For large external tension f , the spring force contributes a subdominant correction ˜1 /f3 /2 to the well-known ˜1 /√{f } -dependence of the end-to-end extension.

  16. The brain as immunoprecipitator of serum autoantibodies against N-Methyl-D-aspartate receptor subunit NR1.

    PubMed

    Castillo-Gomez, Esther; Kästner, Anne; Steiner, Johann; Schneider, Anja; Hettling, Bilke; Poggi, Giulia; Ostehr, Kristin; Uhr, Manfred; Asif, Abdul R; Matzke, Mike; Schmidt, Ulrike; Pfander, Viktoria; Hammer, Christian; Schulz, Thomas F; Binder, Lutz; Stöcker, Winfried; Weber, Frank; Ehrenreich, Hannelore

    2016-01-01

    Autoantibodies (AB) against N-methyl-D-aspartate receptor subunit NR1 (NMDAR1) are highly seroprevalent in health and disease. Symptomatic relevance may arise upon compromised blood-brain barrier (BBB). However, it remained unknown whether circulating NMDAR1 AB appear in the cerebrospinal fluid (CSF). Of n = 271 subjects with CSF-serum pairs, 26 were NMDAR1 AB seropositive, but only 1 was CSF positive. Contrariwise, tetanus AB (non-brain-binding) were present in serum and CSF of all subjects, with CSF levels higher upon BBB dysfunction. Translational mouse experiments proved the hypothesis that the brain acts as an 'immunoprecipitator'; simultaneous injection of NMDAR1 AB and the non-brain-binding green fluorescent protein AB resulted in high detectability of the former in brain and the latter in CSF. PMID:26505629

  17. Role of a novel dual flavin reductase (NR1) and an associated histidine triad protein (DCS-1) in menadione-induced cytotoxicity

    SciTech Connect

    Kwasnicka-Crawford, Dorota A.; Vincent, Steven R. . E-mail: svincent@interchg.ubc.ca

    2005-10-21

    Microsomal cytochrome P450 reductase catalyzes the one-electron transfer from NADPH via FAD and FMN to various electron acceptors, such as cytochrome P450s or to some anti-cancer quinone drugs. This results in generation of free radicals and toxic oxygen metabolites, which can contribute to the cytotoxicity of these compounds. Recently, a cytosolic NADPH-dependent flavin reductase, NR1, has been described which is highly homologous to the microsomal cytochrome P450 reductase. In this study, we show that over-expression of NR1 in human embryonic kidney cells enhances the cytotoxic action of the model quinone, menadione. Furthermore, we show that a novel human histidine triad protein DCS-1, which is expressed together with NR1 in many tissues, can significantly reduce menadione-induced cytotoxicity in these cells. We also show that DCS-1 binds NF1 and directly modulates its activity. These results suggest that NR1 may play a role in carcinogenicity and cell death associated with one-electron reductions.

  18. Acute hypoxia differentially affects the NMDA receptor NR1, NR2A and NR2B subunit mRNA levels in the developing chick optic tectum: stage-dependent plasticity in the 2B-2A ratio.

    PubMed

    Vacotto, Marina; Rapacioli, Melina; Flores, Vladimir; de Plazas, Sara Fiszer

    2010-10-01

    It is known that the NMDA-R NR1 subunit is needed for the receptor activity and that under hypoxia the evolution toward apoptosis or neuronal survival depends on the balance NR2A/NR2B subunits. This paper analyzes the effect of acute hypoxia on the above mentioned subunits mRNAs during development. The mean percentage of NR1+ neurons displayed the higher plasticity during development while the NR2A+ neurons the higher stability. Acute hypoxia increased the mean percentage of NR1+ and NR2B+ neurons at ED12 but only that of NR1+ neurons at ED18. Acute hypoxia increased the levels of expression of NR1 and NR2B mRNAs at ED12 without changes in the NR2A mRNA. During early stages there is a higher sensitivity to change the subunits mRNA levels under a hypoxic treatment. At ED12 acute hypoxia increased the probability of co-expression of the NR1-NR2A and NR1-NR2B subunits combinations, the level of NR1 and NR2B and the ratio NR2B/NR2A. These conditions facilitate the evolution towards apoptosis. PMID:20596770

  19. The HR97 (NR1L) Group of Nuclear Receptors: A New Group up of Nuclear Receptors Discovered in Daphnia species

    PubMed Central

    Li, Yangchun; Ginjupalli, Gautam K.; Baldwin, William S.

    2014-01-01

    The recently sequenced Daphnia pulex genome revealed the NR1L nuclear receptor group consisting of three novel receptors. Phylogenetic studies show that this group is related to the NR1I group (CAR/PXR/VDR) and the NR1J group (HR96), and were subsequently named HR97a/b/g. Each of the HR97 paralogs from Daphnia magna, a commonly used crustacean in toxicity testing, was cloned, sequenced, and partially characterized. Phylogenetic analysis indicates that the HR97 receptors are present in primitive arthropods such as the chelicerates but lost in insects. qPCR and immunohistochemistry demonstrate that each of the receptors is expressed near or at reproductive maturity, and that HR97g, the most ancient of the HR97 receptors, is primarily expressed in the gastrointestinal tract, mandibular region, and ovaries, consistent with a role in reproduction. Transactivation assays using an HR97a/b/g-GAL4 chimera indicate that unlike Daphnia HR96 that is promiscuous with respect to ligand recognition, the HR97 receptors do not respond to many of the ligands that activate CAR/PXR/HR96 nuclear receptors. Only three putative ligands of HR97 receptors were identified in this study: pyriproxyfen, methyl farnesoate, and arachidonic acid. Only arachidonic acid, which acts as an inverse agonist, alters HR97g activity at concentrations that would be considered within physiologically relevant ranges. Overall, this study demonstrates that, although closely related to the promiscuous receptors in the NR1I and NR1J groups, the HR97 receptors are mostly likely not multi-xenobiotic sensors, but rather may perform physiological functions, potentially in reproduction, unique to crustaceans and other non-insect arthropod groups. PMID:25092536

  20. Environmental contaminants activate human and polar bear (Ursus maritimus) pregnane X receptors (PXR, NR1I2) differently

    PubMed Central

    Roger, Lille-Langøy; V, Goldstone Jared; Marte, Rusten; R, Milnes Matthew; Rune, Male; J, Stegeman John; Bruce, Blumberg; Anders, Goksøyr

    2015-01-01

    BACKGROUND Many persistent organic pollutants (POPs) accumulate readily in polar bears because of their position as apex predators in Arctic food webs. The pregnane X receptor (PXR, formally NR1I2, here proposed to be named promiscuous xenobiotic receptor) is a xenobiotic sensor that is directly involved in metabolizing pathways of a wide range of environmental contaminants. OBJECTIVES In the present study, we comparably assess the ability of 51 selected pharmaceuticals, pesticides and emerging contaminants to activate PXRs from polar bears and humans using an in vitro luciferase reporter gene assay. RESULTS We found that polar bear PXR is activated by a wide range of our test compounds (68%) but has a slightly more narrow ligand specificity than human PXR that was activated by 86% of the 51 test compounds. The majority of the agonists identified (70%) produces a stronger induction of the reporter gene via human PXR than via polar bear PXR, however with some notable and environmentally relevant exceptions. CONCLUSIONS Due to the observed differences in activation of polar bear and human PXRs, exposure of each species to environmental agents is likely to induce biotransformation differently in the two species. Bioinformatics analyses and structural modelling studies suggests that amino acids that are not part of the ligand-binding domain and do not interact with the ligand can modulate receptor activation. PMID:25680588

  1. Instant and Lasting Down-Regulation of NR1 Expression in the Hippocampus is Associated Temporally with Antidepressant Activity After Acute Yueju.

    PubMed

    Xia, Baomei; Zhang, Hailou; Xue, Wenda; Tao, Weiwei; Chen, Chang; Wu, Ruyan; Ren, Li; Tang, Juanjuan; Wu, Haoxin; Cai, Baochang; Doronc, Ravid; Chen, Gang

    2016-10-01

    Accumulating evidence indicated that N-methyl-D-aspartate (NMDA) receptors are involved in the pathophysiology of depression and implicated in therapeutic targets. NMDA antagonists, such as ketamine, displayed fast-onset and long-lasting antidepressant activity in preclinical and clinical studies. Previous studies showed that Yueju pill exerts antidepressant effects similar to ketamine. Here, we focused on investigating the association of acute and lasting antidepressant responses of Yueju with time course changes of NMDA receptor subunits NR1, NR2A, and NR2B expressions in the hippocampus, a key region regulating depression response. As a result, Yueju reduced immobility time in the forced swimming test from 30 min to 5 days post a single administration. Yueju acutely decreased NR1 and NR2B protein expression in the hippocampus, with NR2A expression unaltered. NR1 expression remained down-regulated 5 days post Yueju administration, whereas NR2B returned to normal level in 24 h. Yueju and ketamine similarly ameliorated the depression-like symptoms at least for 72 h in learned helplessness test. They both reversed the up-regulated expression of NR1 in the learned helpless mice 1 or 3 days post administration. Different from ketamine, the antidepressant effects of Yueju were not influenced by blockade of amino-3-hydroxy-5-methyl-4-isoxazole propionate receptor. These findings served as preclinical evidence that Yueju may confer acute and long-lasting antidepressant effects by favorably modulating NMDA function in the hippocampus. PMID:26825573

  2. The orphan nuclear receptor DAX-1 functions as a potent corepressor of the constitutive androstane receptor (NR1I3).

    PubMed

    Laurenzana, Elizabeth M; Chen, Tao; Kannuswamy, Malavika; Sell, Brian E; Strom, Stephen C; Li, Yong; Omiecinski, Curtis J

    2012-11-01

    Regulation of gene transcription is controlled in part by nuclear receptors that function coordinately with coregulator proteins. The human constitutive androstane receptor (CAR; NR1I3) is expressed primarily in liver and regulates the expression of genes involved in xenobiotic metabolism as well as hormone, energy, and lipid homeostasis. In this report, DAX-1, a nuclear receptor family member with corepressor properties, was identified as a potent CAR regulator. Results of transaction and mutational studies demonstrated that both DAX-1's downstream LXXLL and its PCFQVLP motifs were critical contributors to DAX-1's corepression activities, although two other LXXM/LL motifs located nearer the N terminus had no impact on the CAR functional interaction. Deletion of DAX-1's C-terminal transcription silencing domain restored CAR1 transactivation activity in reporter assays to approximately 90% of control, demonstrating its critical function in mediating the CAR repression activities. Furthermore, results obtained from mammalian two-hybrid experiments assessing various domain configurations of the respective receptors showed that full-length DAX-1 inhibited the CAR-SRC1 interaction by approximately 50%, whereas the same interaction was restored to 90% of control when the DAX-1 transcription silencing domain was deleted. Direct interaction between CAR and DAX-1 was demonstrated with both alpha-screen and coimmunoprecipitation experiments, and this interaction was enhanced in the presence of the CAR activator 6-(4-chlorophenyl)imidazo[2,1-b]thiazole-5-carbaldehyde O-(3,4-dichlorobenzyl)oxime (CITCO). Results obtained in primary human hepatocytes further demonstrated DAX-1 inhibition of CAR-mediated CITCO induction of the CYP2B6 target gene. The results of this investigation identify DAX-1 as a novel and potent CAR corepressor and suggest that DAX-1 functions as a coordinate hepatic regulator of CAR's biological function. PMID:22896671

  3. Environmental contaminants activate human and polar bear (Ursus maritimus) pregnane X receptors (PXR, NR1I2) differently

    SciTech Connect

    Lille-Langøy, Roger; Goldstone, Jared V.; Rusten, Marte; Milnes, Matthew R.; Male, Rune; Stegeman, John J.; Blumberg, Bruce; Goksøyr, Anders

    2015-04-01

    Background: Many persistent organic pollutants (POPs) accumulate readily in polar bears because of their position as apex predators in Arctic food webs. The pregnane X receptor (PXR, formally NR1I2, here proposed to be named promiscuous xenobiotic receptor) is a xenobiotic sensor that is directly involved in metabolizing pathways of a wide range of environmental contaminants. Objectives: In the present study, we comparably assess the ability of 51 selected pharmaceuticals, pesticides and emerging contaminants to activate PXRs from polar bears and humans using an in vitro luciferase reporter gene assay. Results: We found that polar bear PXR is activated by a wide range of our test compounds (68%) but has a slightly more narrow ligand specificity than human PXR that was activated by 86% of the 51 test compounds. The majority of the agonists identified (70%) produces a stronger induction of the reporter gene via human PXR than via polar bear PXR, however with some notable and environmentally relevant exceptions. Conclusions: Due to the observed differences in activation of polar bear and human PXRs, exposure of each species to environmental agents is likely to induce biotransformation differently in the two species. Bioinformatics analyses and structural modeling studies suggest that amino acids that are not part of the ligand-binding domain and do not interact with the ligand can modulate receptor activation. - Highlights: • Comparative study of ligand activation of human and polar bear PXRs. • Polar bear PXR is a promiscuous ligand-activated nuclear receptor but less so than human PXR. • Environmental contaminants activate human and polar bear PXRs differently. • Expression and ligand promiscuity indicate that PXR is a xenosensor in polar bears.

  4. Modifier Genes as Therapeutics: The Nuclear Hormone Receptor Rev Erb Alpha (Nr1d1) Rescues Nr2e3 Associated Retinal Disease

    PubMed Central

    Cruz, Nelly M.; Yuan, Yang; Leehy, Barrett D.; Baid, Rinku; Kompella, Uday; DeAngelis, Margaret M.; Escher, Pascal; Haider, Neena B.

    2014-01-01

    Nuclear hormone receptors play a major role in many important biological processes. Most nuclear hormone receptors are ubiquitously expressed and regulate processes such as metabolism, circadian function, and development. They function in these processes to maintain homeostasis through modulation of transcriptional gene networks. In this study we evaluate the effectiveness of a nuclear hormone receptor gene to modulate retinal degeneration and restore the integrity of the retina. Currently, there are no effective treatment options for retinal degenerative diseases leading to progressive and irreversible blindness. In this study we demonstrate that the nuclear hormone receptor gene Nr1d1 (Rev-Erbα) rescues Nr2e3-associated retinal degeneration in the rd7 mouse, which lacks a functional Nr2e3 gene. Mutations in human NR2E3 are associated with several retinal degenerations including enhanced S cone syndrome and retinitis pigmentosa. The rd7 mouse, lacking Nr2e3, exhibits an increase in S cones and slow, progressive retinal degeneration. A traditional genetic mapping approach previously identified candidate modifier loci. Here, we demonstrate that in vivo delivery of the candidate modifier gene, Nr1d1 rescues Nr2e3 associated retinal degeneration. We observed clinical, histological, functional, and molecular restoration of the rd7 retina. Furthermore, we demonstrate that the mechanism of rescue at the molecular and functional level is through the re-regulation of key genes within the Nr2e3-directed transcriptional network. Together, these findings reveal the potency of nuclear receptors as modulators of disease and specifically of NR1D1 as a novel therapeutic for retinal degenerations. PMID:24498227

  5. Repairing the Brain by SCF+G-CSF Treatment at 6 Months Postexperimental Stroke: Mechanistic Determination of the Causal Link Between Neurovascular Regeneration and Motor Functional Recovery.

    PubMed

    Cui, Lili; Wang, Dandan; McGillis, Sandra; Kyle, Michele; Zhao, Li-Ru

    2016-06-01

    Stroke, a leading cause of adult disability in the world, is a severe medical condition with limited treatment. Physical therapy, the only treatment available for stroke rehabilitation, appears to be effective within 6 months post-stroke. Here, we have mechanistically determined the efficacy of combined two hematopoietic growth factors, stem cell factor (SCF) and granulocyte-colony stimulating factor (G-CSF; SCF + G-CSF), in brain repair 6 months after cortical infarct induction in the transgenic mice carrying yellow fluorescent protein in Layer V pyramidal neurons (Thy1-YFP-H). Using a combination of live brain imaging, whole brain imaging, molecular manipulation, synaptic and vascular assessments, and motor function examination, we found that SCF + G-CSF promoted mushroom spine formation, enlarged postsynaptic membrane size, and increased postsynaptic density-95 accumulation and blood vessel density in the peri-infarct cavity cortex; and that SCF + G-CSF treatment improved motor functional recovery. The SCF + G-CSF-enhanced motor functional recovery was dependent on the synaptic and vascular regeneration in the peri-infarct cavity cortex. These data suggest that a stroke-damaged brain is repairable by SCF + G-CSF even 6 months after the lesion occurs. This study provides novel insights into the development of new restorative strategies for stroke recovery. PMID:27511907

  6. Severity of infantile nystagmus syndrome-like ocular motor phenotype is linked to the extent of the underlying optic nerve projection defect in zebrafish belladonna mutant.

    PubMed

    Huber-Reggi, Sabina P; Chen, Chien-Cheng; Grimm, Lea; Straumann, Dominik; Neuhauss, Stephan C F; Huang, Melody Ying-Yu

    2012-12-12

    Infantile nystagmus syndrome (INS), formerly known as congenital nystagmus, is an ocular motor disorder in humans characterized by spontaneous eye oscillations (SOs) and, in several cases, reversed optokinetic response (OKR). Its etiology and pathomechanism is largely unknown, but misrouting of the optic nerve has been observed in some patients. Likewise, optic nerve misrouting, a reversed OKR and SOs with INS-like waveforms are observed in zebrafish belladonna (bel) mutants. We aimed to investigate whether and how misrouting of the optic nerve correlates with the ocular motor behaviors in bel larvae. OKR and SOs were quantified and subsequently the optic nerve fibers were stained with fluorescent lipophilic dyes. Eye velocity during OKR was reduced in larvae with few misprojecting optic nerve fibers and reversed in larvae with a substantial fraction of misprojecting fibers. All larvae with reversed OKR also displayed SOs. A stronger reversed OKR correlated with more frequent SOs. Since we did not find a correlation between additional retinal defects and ocular motor behavior, we suggest that axon misrouting is in fact origin of INS in the zebrafish animal model. Depending on the ratio between misprojecting ipsilateral and correctly projecting contralateral fibers, the negative feedback loop normally regulating OKR can turn into a positive loop, resulting in an increase in retinal slip. Our data not only give new insights into the etiology of INS but may also be of interest for studies on how the brain deals with and adapts to conflicting inputs. PMID:23238723

  7. Key Amino Acid Residues within the Third Membrane Domains of NR1 and NR2 Subunits Contribute to the Regulation of the Surface Delivery of N-methyl-d-aspartate Receptors*

    PubMed Central

    Kaniakova, Martina; Krausova, Barbora; Vyklicky, Vojtech; Korinek, Miloslav; Lichnerova, Katarina; Vyklicky, Ladislav; Horak, Martin

    2012-01-01

    N-methyl-d-aspartate (NMDA) receptors are glutamate ionotropic receptors that play critical roles in synaptic transmission, plasticity, and excitotoxicity. The functional NMDA receptors, heterotetramers composed mainly of two NR1 and two NR2 subunits, likely pass endoplasmic reticulum quality control before they are released from the endoplasmic reticulum and trafficked to the cell surface. However, the mechanism underlying this process is not clear. Using truncated and mutated NMDA receptor subunits expressed in heterologous cells, we found that the M3 domains of both NR1 and NR2 subunits contain key amino acid residues that contribute to the regulation of the number of surface functional NMDA receptors. These key residues are critical neither for the interaction between the NR1 and NR2 subunits nor for the formation of the functional receptors, but rather they regulate the early trafficking of the receptors. We also found that the identified key amino acid residues within both NR1 and NR2 M3 domains contribute to the regulation of the surface expression of unassembled NR1 and NR2 subunits. Thus, our data identify the unique role of the membrane domains in the regulation of the number of surface NMDA receptors. PMID:22711533

  8. Early musical training is linked to gray matter structure in the ventral premotor cortex and auditory-motor rhythm synchronization performance.

    PubMed

    Bailey, Jennifer Anne; Zatorre, Robert J; Penhune, Virginia B

    2014-04-01

    Evidence in animals and humans indicates that there are sensitive periods during development, times when experience or stimulation has a greater influence on behavior and brain structure. Sensitive periods are the result of an interaction between maturational processes and experience-dependent plasticity mechanisms. Previous work from our laboratory has shown that adult musicians who begin training before the age of 7 show enhancements in behavior and white matter structure compared with those who begin later. Plastic changes in white matter and gray matter are hypothesized to co-occur; therefore, the current study investigated possible differences in gray matter structure between early-trained (ET; <7) and late-trained (LT; >7) musicians, matched for years of experience. Gray matter structure was assessed using voxel-wise analysis techniques (optimized voxel-based morphometry, traditional voxel-based morphometry, and deformation-based morphometry) and surface-based measures (cortical thickness, surface area and mean curvature). Deformation-based morphometry analyses identified group differences between ET and LT musicians in right ventral premotor cortex (vPMC), which correlated with performance on an auditory motor synchronization task and with age of onset of musical training. In addition, cortical surface area in vPMC was greater for ET musicians. These results are consistent with evidence that premotor cortex shows greatest maturational change between the ages of 6-9 years and that this region is important for integrating auditory and motor information. We propose that the auditory and motor interactions required by musical practice drive plasticity in vPMC and that this plasticity is greatest when maturation is near its peak. PMID:24236696

  9. Steering by Hearing: A Bat’s Acoustic Gaze Is Linked to Its Flight Motor Output by a Delayed, Adaptive Linear Law

    PubMed Central

    Ghose, Kaushik; Moss, Cynthia F.

    2012-01-01

    Adaptive behaviors require sensorimotor computations that convert information represented initially in sensory coordinates to commands for action in motor coordinates. Fundamental to these computations is the relationship between the region of the environment sensed by the animal (gaze) and the animal’s locomotor plan. Studies of visually guided animals have revealed an anticipatory relationship between gaze direction and the locomotor plan during target-directed locomotion. Here, we study an acoustically guided animal, an echolocating bat, and relate acoustic gaze (direction of the sonar beam) to flight planning as the bat searches for and intercepts insect prey. We show differences in the relationship between gaze and locomotion as the bat progresses through different phases of insect pursuit. We define acoustic gaze angle, θgaze, to be the angle between the sonar beam axis and the bat’s flight path. We show that there is a strong linear linkage between acoustic gaze angle at time t [θgaze(t)] and flight turn rate at time t + τ into the future [θ̇flight (t + τ)], which can be expressed by the formula θ̇flight (t + τ) = kθgaze(t). The gain, k, of this linkage depends on the bat’s behavioral state, which is indexed by its sonar pulse rate. For high pulse rates, associated with insect attacking behavior, k is twice as high compared with low pulse rates, associated with searching behavior. We suggest that this adjustable linkage between acoustic gaze and motor output in a flying echolocating bat simplifies the transformation of auditory information to flight motor commands. PMID:16467518

  10. Linking Aβ42-Induced Hyperexcitability to Neurodegeneration, Learning and Motor Deficits, and a Shorter Lifespan in an Alzheimer’s Model

    PubMed Central

    Vo-Ba, Dai-An; Licursi, Ashley; Bao, Han; Ganoe, Logan; Finch, Kelly; Tsunoda, Susan

    2015-01-01

    Alzheimer’s disease (AD) is the most prevalent form of dementia in the elderly. β-amyloid (Aβ) accumulation in the brain is thought to be a primary event leading to eventual cognitive and motor dysfunction in AD. Aβ has been shown to promote neuronal hyperactivity, which is consistent with enhanced seizure activity in mouse models and AD patients. Little, however, is known about whether, and how, increased excitability contributes to downstream pathologies of AD. Here, we show that overexpression of human Aβ42 in a Drosophila model indeed induces increased neuronal activity. We found that the underlying mechanism involves the selective degradation of the A-type K+ channel, Kv4. An age-dependent loss of Kv4 leads to an increased probability of AP firing. Interestingly, we find that loss of Kv4 alone results in learning and locomotion defects, as well as a shortened lifespan. To test whether the Aβ42-induced increase in neuronal excitability contributes to, or exacerbates, downstream pathologies, we transgenically over-expressed Kv4 to near wild-type levels in Aβ42-expressing animals. We show that restoration of Kv4 attenuated age-dependent learning and locomotor deficits, slowed the onset of neurodegeneration, and partially rescued premature death seen in Aβ42-expressing animals. We conclude that Aβ42-induced hyperactivity plays a critical role in the age-dependent cognitive and motor decline of this Aβ42-Drosophila model, and possibly in AD. PMID:25774758

  11. Association between Community Ambulation Walking Patterns and Cognitive Function in Patients with Parkinson's Disease: Further Insights into Motor-Cognitive Links

    PubMed Central

    Weiss, Aner; Herman, Talia; Giladi, Nir; Hausdorff, Jeffrey M.

    2015-01-01

    Background. Cognitive function is generally evaluated based on testing in the clinic, but this may not always reflect real-life function. We tested whether parameters derived from long-term, continuous monitoring of gait are associated with cognitive function in patients with Parkinson's disease (PD). Methods. 107 patients with PD (age: 64.9 ± 9.3 yrs; UPDRS motor sum “off”: 40.4 ± 13.2; 25.23% women) wore a 3D accelerometer on their lower back for 3 days. Computerized measures of global cognitive function, executive function, attention, and nonverbal memory were assessed. Three-day acceleration derived measures included cadence, variability, bilateral coordination, and dynamic postural control. Associations between the acceleration derived measures and cognitive function were determined. Results. Linear regression showed associations between vertical gait variability and cadence and between global cognitive score, attention, and executive function (p ≤ 0.048). Dynamic postural control was associated with global cognitive score and attention (p ≤ 0.027). Nonverbal memory was not associated with the acceleration-derived measures. Conclusions. These findings suggest that metrics derived from a 3-day worn body-fixed sensor reflect cognitive function, further supporting the idea that the gait pattern may be altered as cognition declines and that gait provides a window into cognitive function in patients with PD. PMID:26605103

  12. Mechanisms responsible for the effect of median nerve electrical stimulation on traumatic brain injury-induced coma: orexin-A-mediated N-methyl-D-aspartate receptor subunit NR1 upregulation

    PubMed Central

    Feng, Zhen; Du, Qing

    2016-01-01

    Electrical stimulation of the median nerve is a noninvasive technique that facilitates awakening from coma. In rats with traumatic brain injury-induced coma, median nerve stimulation markedly enhances prefrontal cortex expression of orexin-A and its receptor, orexin receptor 1. To further understand the mechanism underlying wakefulness mediated by electrical stimulation of the median nerve, we evaluated its effects on the expression of the N-methyl-D-aspartate receptor subunit NR1 in the prefrontal cortex in rat models of traumatic brain injury-induced coma, using immunohistochemistry and western blot assays. In rats with traumatic brain injury, NR1 expression increased with time after injury. Rats that underwent electrical stimulation of the median nerve (30 Hz, 0.5 ms, 1.0 mA for 15 minutes) showed elevated NR1 expression and greater recovery of consciousness than those without stimulation. These effects were reduced by intracerebroventricular injection of the orexin receptor 1 antagonist SB334867. Our results indicate that electrical stimulation of the median nerve promotes recovery from traumatic brain injury-induced coma by increasing prefrontal cortex NR1 expression via an orexin-A-mediated pathway. PMID:27482224

  13. The circadian clock regulates autophagy directly through the nuclear hormone receptor Nr1d1/Rev-erbα and indirectly via Cebpb/(C/ebpβ) in zebrafish.

    PubMed

    Huang, Guodong; Zhang, Fanmiao; Ye, Qiang; Wang, Han

    2016-08-01

    Autophagy is a highly conserved intracellular degradation system, and recently was shown to display circadian rhythms in mice. The mechanisms underlying circadian regulation of autophagy, however, are still unclear. Here, we observed that numbers of autophagosomes and autolysosomes exhibit daily rhythms in the zebrafish liver, and cebpb/(c/ebpβ) and various autophagy genes are rhythmically expressed in zebrafish larvae but significantly upregulated in per1b and TALEN-generated nr1d1/rev-erbα mutant fish, indicating that both Per1b and Nr1d1 play critical roles in autophagy rhythms. Luciferase reporter and ChIP assays show that the circadian clock directly regulates autophagy genes through Nr1d1, and also regulates transcription of cebpb through Per1b. We also found that fasting leads to altered expression of both circadian clock genes and autophagy genes in zebrafish adult peripheral organs. Further, transcriptome analysis reveals multiple functions of Nr1d1 in zebrafish. Taken together, these findings provide evidence for how the circadian clock regulates autophagy, imply that nutritional signaling affects both circadian regulation and autophagy activities in peripheral organs, and shed light on how circadian gene mutations act through autophagy to contribute to common metabolic diseases such as obesity. PMID:27171500

  14. The circadian clock regulates autophagy directly through the nuclear hormone receptor Nr1d1/Rev-erbα and indirectly via Cebpb/(C/ebpβ) in zebrafish

    PubMed Central

    Huang, Guodong; Zhang, Fanmiao; Ye, Qiang; Wang, Han

    2016-01-01

    ABSTRACT Autophagy is a highly conserved intracellular degradation system, and recently was shown to display circadian rhythms in mice. The mechanisms underlying circadian regulation of autophagy, however, are still unclear. Here, we observed that numbers of autophagosomes and autolysosomes exhibit daily rhythms in the zebrafish liver, and cebpb/(c/ebpβ) and various autophagy genes are rhythmically expressed in zebrafish larvae but significantly upregulated in per1b and TALEN-generated nr1d1/rev-erbα mutant fish, indicating that both Per1b and Nr1d1 play critical roles in autophagy rhythms. Luciferase reporter and ChIP assays show that the circadian clock directly regulates autophagy genes through Nr1d1, and also regulates transcription of cebpb through Per1b. We also found that fasting leads to altered expression of both circadian clock genes and autophagy genes in zebrafish adult peripheral organs. Further, transcriptome analysis reveals multiple functions of Nr1d1 in zebrafish. Taken together, these findings provide evidence for how the circadian clock regulates autophagy, imply that nutritional signaling affects both circadian regulation and autophagy activities in peripheral organs, and shed light on how circadian gene mutations act through autophagy to contribute to common metabolic diseases such as obesity. PMID:27171500

  15. Mechanisms responsible for the effect of median nerve electrical stimulation on traumatic brain injury-induced coma: orexin-A-mediated N-methyl-D-aspartate receptor subunit NR1 upregulation.

    PubMed

    Feng, Zhen; Du, Qing

    2016-06-01

    Electrical stimulation of the median nerve is a noninvasive technique that facilitates awakening from coma. In rats with traumatic brain injury-induced coma, median nerve stimulation markedly enhances prefrontal cortex expression of orexin-A and its receptor, orexin receptor 1. To further understand the mechanism underlying wakefulness mediated by electrical stimulation of the median nerve, we evaluated its effects on the expression of the N-methyl-D-aspartate receptor subunit NR1 in the prefrontal cortex in rat models of traumatic brain injury-induced coma, using immunohistochemistry and western blot assays. In rats with traumatic brain injury, NR1 expression increased with time after injury. Rats that underwent electrical stimulation of the median nerve (30 Hz, 0.5 ms, 1.0 mA for 15 minutes) showed elevated NR1 expression and greater recovery of consciousness than those without stimulation. These effects were reduced by intracerebroventricular injection of the orexin receptor 1 antagonist SB334867. Our results indicate that electrical stimulation of the median nerve promotes recovery from traumatic brain injury-induced coma by increasing prefrontal cortex NR1 expression via an orexin-A-mediated pathway. PMID:27482224

  16. Cytogenetic evaluation and the association with polymorphisms of the CPY1A1 and NR1I3 genes in individuals exposed to BTEX.

    PubMed

    da Rosa, João Carlos Fraga; Fiegenbaum, Marilu; Soledar, Ane Lise; Claus, Matheus Souza; de Souza Nunes, Antonio Daniel; Cardoso, Valesca Veiga

    2013-07-01

    The gas station attendants are exposed daily to chemical agents that compose gasoline, such as BTEX (benzene, toluene, ethylbenzene, and xylene), and the exposure to these agents can cause a variety of effects on the human health. Among the various possible cell alterations associated with these exposures are the formation of micronuclei and of binucleated cells which are used as indicators of clastogenic action. Benzene, the main carcinogenic agent, is metabolized to more soluble forms and easily excreted by isoenzymes of cytochrome P450, such as CYP1A1. The CYP1A1 gene is highly polymorphic and one of its allele variations can be detected by the use of restriction endonucleasis MspI and is originated by the transition of a thymine by a cytosine (3798T>C), resulting in the polymorphic allele CYP1A1*2A. The objective of this study was to evaluate the cytogenetic damage induced by the exposure to BTEX and to associate it with the polymorphisms of the CYP1A1 and NR1I3 genes. Samples of exfoliated cells from the oral mucosa of 27 gas station attendants and from a control group were collected. The results found show that the group exposed to BTEX presents significantly higher alterations than those in the control group for micronuclei (MN; 6.85 ± 1.33 vs. 2.96 ± 1.91, P < 0.001) and for the total of nuclear alterations observed (MN + binucleated cells (BNC); 9.59 ± 4.73 vs. 5.07 ± 2.21, P < 0.001). When comparing the cytological alterations and the genotypes among the exposed individuals for the polymorphism 3798T>C of the CYP1A1 gene, homozygotes TT present MN + BNC significantly higher than carriers of the allele C (10.88 ± 5.36 vs. 5.33 ± 2.52, P = 0.028). No association was observed in the control group or for the NR1I3 gene. These results show that molecular and cytogenetic data can be used in the future as tools to monitor individuals exposed to such compounds. PMID:23138419

  17. Pharmacological characterization of recombinant NR1/NR2A NMDA receptors with truncated and deleted carboxy termini expressed in Xenopus laevis oocytes

    PubMed Central

    Puddifoot, CA; Chen, PE; Schoepfer, R; Wyllie, DJA

    2009-01-01

    Background and purpose: The carboxy terminal domain (CTD) of NR2 N-methyl-d-aspartate receptor (NMDAR) subunits interacts with numerous scaffolding and signal transduction proteins. Mutations of this region affect trafficking and downstream signalling of NMDARs. This study determines to what extent characteristic pharmacological properties of NR2A-containing NMDARs are influenced by this key functional domain. Experimental approach: Using recombinant receptor expression in Xenopus laevis oocytes and two electrode voltage clamp recordings we characterized pharmacological properties of rat NR1/NR2A NMDARs with altered CTDs. We assessed the effects of truncating [at residue Iso1098; NR2A(trunC)] and deleting [from residue Phe822; NR2A(delC)] the CTD of NR2A NMDAR subunits on agonist potencies, channel block by Mg2+ and memantine and potentiation of NMDAR-mediated responses by chelating contaminating divalent cations. Key results: Truncation or deletion of the CTD of NR2A NMDAR subunits did not affect glutamate potency [EC50 = 2.2 µmol·L−1, NR2A(trunC); 2.7 µmol·L−1, NR2A(delC) compared with 3.3 µmol·L−1, NR2A(WT)] but did significantly increase glycine potency [EC50 = 500 nmol·L−1, NR2A(trunC); 900 nmol·L−1, NR2A(delC) compared with 1.3 µmol·L−1, NR2A(WT)]. Voltage-dependent Mg2+ block of NR2A(WT)- and NR2A(trunC)-containing NMDARs was similar but low concentrations of Mg2+ (1 µmol·L−1) potentiated NR1/NR2A(delC) NMDARs. Memantine block was not affected by changes to the structure of the NR2A CTD. EDTA-induced potentiation was similar at each of the three NMDAR constructs. Conclusions and implications: Of the parameters studied only minor influences of the CTD were observed; these are unlikely to compromise interpretation of studies that make use of CTD-mutated recombinant receptors or transgenic mice in investigations of the role of the CTD in NMDAR signalling. PMID:19154422

  18. Motor Starters

    NASA Technical Reports Server (NTRS)

    1986-01-01

    The power factor controller (PFC) was invented by a NASA engineer. It matches voltage with a motor's actual need by sensing shifts in the relationship between voltage and current flow. With the device, power can be trimmed as much as 65%. Intellinet adopted this technology and designed "soft start" and "load-responsive" control modes to start engines gradually and recycle voltage without reducing motor speed. Other features are lower motor heat and faster fault identification.

  19. Motor syndromes.

    PubMed

    Corea, Francesco; Micheli, Sara

    2012-01-01

    Motor disturbances alone or associated with other focal deficits are the most common symptoms suggesting a neurovascular event. An appropriate clinical assessment of these signs and symptoms may help physicians to better diagnose and to both better treat and predict outcome. In this paper the main clinical features of motor deficit are described together with other motor-related events such as ataxia and movement disturbances. PMID:22377850

  20. Molecular motors

    NASA Astrophysics Data System (ADS)

    Allemand, Jean François Desbiolles, Pierre

    2015-10-01

    How do we move? More precisely, what are the molecular mechanisms that can explain that our muscles, made of very small components can move at a osopic scale? To answer these questions we must introduce molecular motors. Those motors are proteins, or small protein assemblies that, in our cells, transform chemical energy into mechanical work. Then, like we could do for a oscopic motor, used in a car or in a fan, we are going to study the basic behavior of these molecular machines, present what are their energy sources, calculate their power, their yield. If molecular motors are crucial for our oscopic movements, we are going to see that they are also essential to cellular transport and that considering the activity of some enzymes as molecular motors bring some interesting new insights on their activity.

  1. Fine-tuning motor torque

    SciTech Connect

    O`Connor, L.

    1996-01-01

    Direct-torque control, a new method of regulating the output of ac induction motors, provides a swift response to input commands. A new variable-speed ac motor drive system that responds to torque input commands 10 times faster than current state-of-the-art drives has been developed by ABB Industrial Systems Inc. in New Berlin, Wis. The new control system, called the ACS 600, provides an alternative to drive systems that use sophisticated flux vector control or more routine pulse width modulation--the primary methods of regulating the output of ac induction motors. The ACS 600 is suitable for use in single motor applications that require a standard level of performance, such as conveyors, fans, and pumps. But it will likely be more valuable in applications that require the linking of multiple motors, such as textile production, and in applications that require tight control over torque, such as cranes, elevators, and centrifuges.

  2. Interaction of ApoA-IV with NR4A1 and NR1D1 Represses G6Pase and PEPCK Transcription: Nuclear Receptor-Mediated Downregulation of Hepatic Gluconeogenesis in Mice and a Human Hepatocyte Cell Line

    PubMed Central

    Li, Xiaoming; Xu, Min; Wang, Fei; Ji, Yong; DavidsoN, W. Sean; Li, Zongfang; Tso, Patrick

    2015-01-01

    We have previously shown that the nuclear receptor, NR1D1, is a cofactor in ApoA-IV-mediated downregulation of gluconeogenesis. Nuclear receptor, NR4A1, is involved in the transcriptional regulation of various genes involved in inflammation, apoptosis, and glucose metabolism. We investigated whether NR4A1 influences the effect of ApoA-IV on hepatic glucose metabolism. Our in situ proximity ligation assays and coimmunoprecipitation experiments indicated that ApoA-IV colocalized with NR4A1 in human liver (HepG2) and kidney (HEK-293) cell lines. The chromatin immunoprecipitation experiments and luciferase reporter assays indicated that the ApoA-IV and NR4A1 colocalized at the RORα response element of the human G6Pase promoter, reducing its transcriptional activity. Our RNA interference experiments showed that knocking down the expression of NR4A1 in primary mouse hepatocytes treated with ApoA-IV increased the expression of NR1D1, G6Pase, and PEPCK, and that knocking down NR1D1 expression increased the level of NR4A1. We also found that ApoA-IV induced the expression of endogenous NR4A1 in both cultured primary mouse hepatocytes and in the mouse liver, and decreased glucose production in primary mouse hepatocytes. Our findings showed that ApoA-IV colocalizes with NR4A1, which suppresses G6Pase and PEPCK gene expression at the transcriptional level, reducing hepatic glucose output and lowering blood glucose. The ApoA-IV-induced increase in NR4A1 expression in hepatocytes mediates further repression of gluconeogenesis. Our findings suggest that NR1D1 and NR4A1 serve similar or complementary functions in the ApoA-IV-mediated regulation of gluconeogenesis. PMID:26556724

  3. Motor Controller

    NASA Technical Reports Server (NTRS)

    1988-01-01

    M.H. Marks Enterprises' Power Factor Controller (PFC) matches voltage with motor's actual need. Plugged into a motor, PFC continuously determines motor load by sensing shifts between voltage and current flow. When it senses a light load, it cuts voltage to the minimum needed. It offers potential energy savings ranging from eight percent up to 65 percent depending on the application. Myles Marks started out with the notion of writing an article for Popular Electronics magazine at the same time offering to furnish kits to readers interested in assembling PFC's. Within two weeks from publication he had orders for 500 kits and orders are still coming three years later.

  4. Stepper motor

    NASA Technical Reports Server (NTRS)

    Dekramer, Cornelis

    1994-01-01

    The purpose of this document is to describe the more commonly used permanent magnet stepper motors for spaceflight. It will discuss the mechanical and electrical aspects of the devices, their torque behavior, those parameters which need to be controlled and measured, and test methods to be employed. It will also discuss torque margins, compare these to the existing margin requirements, and determine the applicability of these requirements. Finally it will attempt to generate a set of requirements which will be used in any stepper motor procurement and will fully characterize the stepper motor behavior in a consistent and repeatable fashion.

  5. A neuroligin-1-derived peptide stimulates phosphorylation of the NMDA receptor NR1 subunit and rescues MK-801-induced decrease in long-term potentiation and memory impairment.

    PubMed

    Korshunova, Irina; Gjørlund, Michelle D; Owczarek, Sylwia; Petersen, Anders V; Perrier, Jean-François; Gøtzsche, Casper René; Berezin, Vladimir

    2015-03-01

    Neuroligins (NLs) are postsynaptic adhesion molecules, interacting with presynaptic neurexins (NXs), which determine the differential formation of excitatory (glutamatergic, NL1) and inhibitory (GABAergic, NL2) synapses. We have previously demonstrated that treatment with a NL2-derived peptide, neurolide-2, reduces sociability and increase animal aggression. We hypothesized that interfering with NL1 function at the excitatory synapses might regulate synaptic plasticity and learning, and counteract memory deficits induced by N-methyl-d-aspartate (NMDA) receptor inhibition. First, neuronal NMDA receptor phosphorylation after treatment with NL1 or a mimetic peptide, neurolide-1, was quantified by immunoblotting. Subsequently, we investigated effects of neurolide-1 on long-term potentiation (LTP) induction in hippocampal slices compromised by NMDA receptor inhibitor MK-801. Finally, we investigated neurolide-1 effects on short- and long-term social and spatial memory in social recognition, Morris water-maze, and Y-maze tests. We found that subcutaneous neurolide-1 administration, restored hippocampal LTP compromised by NMDA receptor inhibitor MK-801. It counteracted MK-801-induced memory deficit in the water-maze and Y-maze tests after long-term treatment (24 h and 1-2 h before the test), but not after short-term exposure (1-2 h). Long-term exposure to neurolide-1 also facilitated social recognition memory. In addition, neurolide-1-induced phosphorylation of the NMDA receptor NR1 subunit on a site important for synaptic trafficking, potentially favoring synaptic receptor retention. Our findings emphasize the role of NL1-NMDA receptor interaction in cognition, and identify neurolide-1, as a valuable pharmacological tool to examine the in vivo role of postsynaptic NL1 in cognitive behavior in physiological and pathological conditions. PMID:26038702

  6. Chaotic motors

    NASA Astrophysics Data System (ADS)

    Laroche, C.; Labbé, R.; Pétrélis, F.; Fauve, S.

    2012-02-01

    We show that electric motors and dynamos can be used to illustrate most elementary instabilities or bifurcations discussed in courses on nonlinear oscillators and dynamical systems. These examples are easier to understand and display a richer behavior than the ones commonly used from mechanics, electronics, hydrodynamics, lasers, chemical reactions, and population dynamics. In particular, an electric motor driven by a dynamo can display stationary, Hopf, and codimension-two bifurcations by tuning the driving speed of the dynamo and the electric current in the stator of the electric motor. When the dynamo is driven at constant torque instead of constant rotation rate, chaotic reversals of the generated current and of the angular rotation of the motor are observed. Simple deterministic models are presented which capture the observed dynamical regimes.

  7. Advanced Motors

    SciTech Connect

    Knoth, Edward A; Chelluri, Bhanumathi; Schumaker, Edward J

    2012-12-14

    vProject Summary Transportation energy usage is predicted to increase substantially by 2020. Hybrid vehicles and fuel cell powered vehicles are destined to become more prominent as fuel prices rise with the demand. Hybrid and fuel cell vehicle platforms are both dependent on high performance electric motors. Electric motors for transportation duty will require sizeable low-speed torque to accelerate the vehicle. As motor speed increases, the torque requirement decreases which results in a nearly constant power motor output. Interior permanent magnet synchronous motors (IPMSM) are well suited for this duty. , , These rotor geometries are configured in straight lines and semi circular arc shapes. These designs are of limited configurations because of the lack of availability of permanent magnets of any other shapes at present. We propose to fabricate rotors via a novel processing approach where we start with magnet powders and compact them into a net shape rotor in a single step. Using this approach, widely different rotor designs can be implemented for efficiency. The current limitation on magnet shape and thickness will be eliminated. This is accomplished by co-filling magnet and soft iron powders at specified locations in intricate shapes using specially designed dies and automatic powder filling station. The process fundamentals for accomplishing occurred under a previous Applied Technology Program titled, Motors and Generators for the 21st Century. New efficient motor designs that are not currently possible (or cost prohibitive) can be accomplished by this approach. Such an approach to motor fabrication opens up a new dimension in motor design. Feasibility Results We were able to optimize a IPMSM rotor to take advantage of the powder co-filling and DMC compaction processing methods. The minimum low speed torque requirement of 5 N-m can be met through an optimized design with magnet material having a Br capability of 0.2 T. This level of magnetic performance can

  8. Motor Planning.

    PubMed

    Wong, Aaron L; Haith, Adrian M; Krakauer, John W

    2015-08-01

    Motor planning colloquially refers to any process related to the preparation of a movement that occurs during the reaction time prior to movement onset. However, this broad definition encompasses processes that are not strictly motor-related, such as decision-making about the identity of task-relevant stimuli in the environment. Furthermore, the assumption that all motor-planning processes require processing time, and can therefore be studied behaviorally by measuring changes in the reaction time, needs to be reexamined. In this review, we take a critical look at the processes leading from perception to action and suggest a definition of motor planning that encompasses only those processes necessary for a movement to be executed-that is, processes that are strictly movement related. These processes resolve the ambiguity inherent in an abstract goal by defining a specific movement to achieve it. We propose that the majority of processes that meet this definition can be completed nearly instantaneously, which means that motor planning itself in fact consumes only a small fraction of the reaction time. PMID:24981338

  9. Multilevel DC link inverter

    DOEpatents

    Su, Gui-Jia

    2003-06-10

    A multilevel DC link inverter and method for improving torque response and current regulation in permanent magnet motors and switched reluctance motors having a low inductance includes a plurality of voltage controlled cells connected in series for applying a resulting dc voltage comprised of one or more incremental dc voltages. The cells are provided with switches for increasing the resulting applied dc voltage as speed and back EMF increase, while limiting the voltage that is applied to the commutation switches to perform PWM or dc voltage stepping functions, so as to limit current ripple in the stator windings below an acceptable level, typically 5%. Several embodiments are disclosed including inverters using IGBT's, inverters using thyristors. All of the inverters are operable in both motoring and regenerating modes.

  10. Motor Dynamics of Embodied Cognition

    ERIC Educational Resources Information Center

    Anderson, Sarah Elizabeth

    2011-01-01

    Predominant theories of cognition have previously emphasized the modularity of processing, in which individual isolated modules process information free from the influence of other types of information. However, more recent theories suggest that cognition is much more linked to motor and sensory processes than modular theories suggest. In this…

  11. Motor Controllers

    NASA Technical Reports Server (NTRS)

    1984-01-01

    Kollmorgen Corporation's Mermaid II two person submersible is propeller-driven by a system of five DC brushless motors with new electronic controllers that originated in work performed in a NASA/DOE project managed by Lewis Research Center. A key feature of the system is electric commutation rather than mechanical commutation for converting AC current to DC.

  12. Therma motor

    DOEpatents

    Kandarian, R.

    The disclosure is directed to a thermal motor utilizing two tapered prestressed parallel adjacent cylinders lengthwise disposed about one third in a coolant. Heat is applied to contacting portions of the cylinders outside the coolant to cause them to deform and turn. Heat sources such as industrial waste heat, geothermal hot water, solar radiation, etc. can be used.

  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. The Development of Oral Motor Control and Language

    ERIC Educational Resources Information Center

    Alcock, Katie

    2006-01-01

    Motor control has long been associated with language skill, in deficits, both acquired and developmental, and in typical development. Most evidence comes from limb praxis however; the link between oral motor control and speech and language has been neglected, despite the fact that most language users talk with their mouths. Oral motor control is…

  16. Motor Proficiency Predicts Cognitive Ability in Four-Year-Olds

    ERIC Educational Resources Information Center

    Hernandez, Amanda Martinez; Caçola, Priscila

    2015-01-01

    Research has shown links between motor proficiency and cognition in school-age children, however, few have explored earlier ages. We aimed to determine the association between motor proficiency and cognitive ability in four-year-olds. Motor and cognitive skills were examined in 32 (15 males, 17 females) four-year-olds (±5.59 months) using the…

  17. Associations of CYP3A4, NR1I2, CYP2C19 and P2RY12 polymorphisms with clopidogrel resistance in Chinese patients with ischemic stroke

    PubMed Central

    Liu, Rui; Zhou, Zi-yi; Chen, Yi-bei; Li, Jia-li; Yu, Wei-bang; Chen, Xin-meng; Zhao, Min; Zhao, Yuan-qi; Cai, Ye-feng; Jin, Jing; Huang, Min

    2016-01-01

    Aim: There is a high incidence of the antiplatelet drug clopidogrel resistance (CR) in Asian populations. Because clopidogrel is a prodrug, polymorphisms of genes encoding the enzymes involved in its biotransformation may be the primary influential factors. The goal of this study was to investigate the associations of polymorphisms of CYP3A4, NR1I2, CYP2C19 and P2RY12 genes with CR in Chinese patients with ischemic stroke. Methods: A total of 191 patients with ischemic stroke were enrolled. The patients were treated with clopidogrel for at least 5 days. Platelet function was measured by light transmission aggregometry. The SNPs NR1I2 (rs13059232), CYP3A4*1G (rs2242480), CYP2C19*2 (rs4244285) and P2RY12 (rs2046934) were genotyped. Results: The CR rate in this population was 36%. The CYP2C19*2 variant was a risk factor for CR (*2/*2+wt/*2 vs wt/wt, OR: 2.366, 95% CI: 1.180–4.741, P=0.014), whereas the CYP3A4*1G variant had a protective effect on CR (*1/*1 vs *1G/*1G+*1/*1G, OR: 2.360, 95% CI: 1.247–4.468, P=0.008). The NR1I2 (rs13059232) polymorphism was moderately associated with CR (CC vs TT+TC, OR: 0.533, 95% CI: 0.286–0.991, P=0.046). The C allele in P2RY12 (rs2046934) was predicted to be a protective factor for CR (CC+TC vs TT, OR: 0.407, 95% CI: 0.191–0.867, P=0.018). In addition, an association was found between hypertension and CR (P=0.022). Conclusion: The individuals with both the CYP2C19*2 allele and hypertension are at high risk of CR during anti-thrombosis therapy. The CYP3A4*1G allele, P2RY12 (rs2046934) C allele and NR1I2 (rs13059232) CC genotype may be protective factors for CR. The associated SNPs studied may be useful to predict clopidogrel resistance in Chinese patients with ischemic stroke. PMID:27133299

  18. Apraxia and Motor Dysfunction in Corticobasal Syndrome

    PubMed Central

    Burrell, James R.; Hornberger, Michael; Vucic, Steve; Kiernan, Matthew C.; Hodges, John R.

    2014-01-01

    Background Corticobasal syndrome (CBS) is characterized by multifaceted motor system dysfunction and cognitive disturbance; distinctive clinical features include limb apraxia and visuospatial dysfunction. Transcranial magnetic stimulation (TMS) has been used to study motor system dysfunction in CBS, but the relationship of TMS parameters to clinical features has not been studied. The present study explored several hypotheses; firstly, that limb apraxia may be partly due to visuospatial impairment in CBS. Secondly, that motor system dysfunction can be demonstrated in CBS, using threshold-tracking TMS, and is linked to limb apraxia. Finally, that atrophy of the primary motor cortex, studied using voxel-based morphometry analysis (VBM), is associated with motor system dysfunction and limb apraxia in CBS. Methods Imitation of meaningful and meaningless hand gestures was graded to assess limb apraxia, while cognitive performance was assessed using the Addenbrooke's Cognitive Examination – Revised (ACE-R), with particular emphasis placed on the visuospatial subtask. Patients underwent TMS, to assess cortical function, and VBM. Results In total, 17 patients with CBS (7 male, 10 female; mean age 64.4+/− 6.6 years) were studied and compared to 17 matched control subjects. Of the CBS patients, 23.5% had a relatively inexcitable motor cortex, with evidence of cortical dysfunction in the remaining 76.5% patients. Reduced resting motor threshold, and visuospatial performance, correlated with limb apraxia. Patients with a resting motor threshold <50% performed significantly worse on the visuospatial sub-task of the ACE-R than other CBS patients. Cortical function correlated with atrophy of the primary and pre-motor cortices, and the thalamus, while apraxia correlated with atrophy of the pre-motor and parietal cortices. Conclusions Cortical dysfunction appears to underlie the core clinical features of CBS, and is associated with atrophy of the primary motor and pre-motor

  19. Gross motor control

    MedlinePlus

    Gross motor control is the ability to make large, general movements (such as waving an arm or lifting a ... Gross motor control is a milestone in the development of an infant. Infants develop gross motor control before they ...

  20. Multifocal Motor Neuropathy

    MedlinePlus

    ... Diversity Find People About NINDS NINDS Multifocal Motor Neuropathy Information Page Table of Contents (click to jump ... done? Clinical Trials Organizations What is Multifocal Motor Neuropathy? Multifocal motor neuropathy is a progressive muscle disorder ...

  1. Motor control for a brushless DC motor

    NASA Technical Reports Server (NTRS)

    Peterson, William J. (Inventor); Faulkner, Dennis T. (Inventor)

    1985-01-01

    This invention relates to a motor control system for a brushless DC motor having an inverter responsively coupled to the motor control system and in power transmitting relationship to the motor. The motor control system includes a motor rotor speed detecting unit that provides a pulsed waveform signal proportional to rotor speed. This pulsed waveform signal is delivered to the inverter to thereby cause an inverter fundamental current waveform output to the motor to be switched at a rate proportional to said rotor speed. In addition, the fundamental current waveform is also pulse width modulated at a rate proportional to the rotor speed. A fundamental current waveform phase advance circuit is controllingly coupled to the inverter. The phase advance circuit is coupled to receive the pulsed waveform signal from the motor rotor speed detecting unit and phase advance the pulsed waveform signal as a predetermined function of motor speed to thereby cause the fundamental current waveform to be advanced and thereby compensate for fundamental current waveform lag due to motor winding reactance which allows the motor to operate at higher speeds than the motor is rated while providing optimal torque and therefore increased efficiency.

  2. Antibody-mediated targeted gene transfer to NMDA NR1-containing neurons in rat neocortex by helper virus-free HSV-1 vector particles containing a chimeric HSV-1 glycoprotein C--Staphylococcus A protein

    PubMed Central

    Cao, Haiyan; Zhang, Guo-rong; Geller, Alfred I.

    2010-01-01

    Because of the heterogeneous cellular composition of the brain, and especially the forebrain, cell type-specific expression will benefit many potential applications of direct gene transfer. The two prevalent approaches for achieving cell type-specific expression are using a cell type-specific promoter or targeting gene transfer to a specific cell type. Targeted gene transfer with Herpes Simplex Virus (HSV-1) vectors modifies glycoprotein C (gC) to replace the heparin binding domain, which binds to many cell types, with a binding activity for a specific cell surface protein. We previously reported targeted gene transfer to nigrostriatal neurons using chimeric gC--glial cell line-derived neurotrophic factor or gC--brain-derived neurotrophic factor protein. Unfortunately, this approach is limited to cells that express the cognate receptor for either neurotrophic factor. Thus, a general strategy for targeting gene transfer to many different types of neurons is desirable. Antibody-mediated targeted gene transfer has been developed for targeting specific virus vectors to specific peripheral cell types; a specific vector particle protein is modified to contain the Staphylococcus A protein ZZ domain, which binds immunoglobulin (Ig) G. Here, we report antibody-mediated targeted gene transfer of HSV-1 vectors to a specific type of forebrain neuron. We constructed a chimeric gC--ZZ protein, and showed this protein is incorporated into vector particles and binds Ig G. Complexes of these vector particles and an antibody to the NMDA receptor NR1 subunit supported targeted gene transfer to NR1-containing neocortical neurons in the rat brain, with long-term (2 months) expression. PMID:20599821

  3. Auditory plasticity and speech motor learning

    PubMed Central

    Nasir, Sazzad M.; Ostry, David J.

    2009-01-01

    Is plasticity in sensory and motor systems linked? Here, in the context of speech motor learning and perception, we test the idea sensory function is modified by motor learning and, in particular, that speech motor learning affects a speaker's auditory map. We assessed speech motor learning by using a robotic device that displaced the jaw and selectively altered somatosensory feedback during speech. We found that with practice speakers progressively corrected for the mechanical perturbation and after motor learning they also showed systematic changes in their perceptual classification of speech sounds. The perceptual shift was tied to motor learning. Individuals that displayed greater amounts of learning also showed greater perceptual change. Perceptual change was not observed in control subjects that produced the same movements, but in the absence of a force field, nor in subjects that experienced the force field but failed to adapt to the mechanical load. The perceptual effects observed here indicate the involvement of the somatosensory system in the neural processing of speech sounds and suggest that speech motor learning results in changes to auditory perceptual function. PMID:19884506

  4. Simple motor drive system operates heavy hinged door

    NASA Technical Reports Server (NTRS)

    Pitkin, R. G.

    1966-01-01

    Motor drive system remotely operates heavy steel radiation shielding doors. The drive consists of a standard motor reducer unit which is mounted on the door. This reducer drives a sprocket which is linked by chain to a fixed sprocket of the same size on the door jamb.

  5. Directed flux motor

    NASA Technical Reports Server (NTRS)

    Wilson, Andrew (Inventor); Punnoose, Andrew (Inventor); Strausser, Katherine (Inventor); Parikh, Neil (Inventor)

    2011-01-01

    A directed flux motor described utilizes the directed magnetic flux of at least one magnet through ferrous material to drive different planetary gear sets to achieve capabilities in six actuated shafts that are grouped three to a side of the motor. The flux motor also utilizes an interwoven magnet configuration which reduces the overall size of the motor. The motor allows for simple changes to modify the torque to speed ratio of the gearing contained within the motor as well as simple configurations for any number of output shafts up to six. The changes allow for improved manufacturability and reliability within the design.

  6. Optimization of a thermomagnetic motor

    NASA Astrophysics Data System (ADS)

    Trapanese, Marco; Cipriani, Giovanni; Di Dio, Vincenzo; Franzitta, Vincenzo; Viola, Alessia

    2015-05-01

    In this paper, an approach towards the optimization of the Curie motor is presented. The approach is based on a thermal-magnetic coupled dynamic model of the motor, which is obtained by assuming the use of a ferromagnetic material working at temperatures near the Curie point. An analytical expression of the generated torque, which links this quantity to the magnetic, thermal, and geometrical parameters of the generated torque, is given. The expressions of speed and torque are derived and related to the thermal properties of the machine and are used as optimization indexes in an optimization procedure. The aim of the optimization process is to obtain a machine able to rotate constantly at the maximum achievable power. A design of a machine, based on this theory, is proposed and the related performances are numerically simulated. A preliminary experimental verification of the performances is reported.

  7. Transcriptome profile analysis of young floral buds of fertile and sterile plants from the self-pollinated offspring of the hybrid between novel restorer line NR1 and Nsa CMS line in Brassica napus

    PubMed Central

    2013-01-01

    Background The fertile and sterile plants were derived from the self-pollinated offspring of the F1 hybrid between the novel restorer line NR1 and the Nsa CMS line in Brassica napus. To elucidate gene expression and regulation caused by the A and C subgenomes of B. napus, as well as the alien chromosome and cytoplasm from Sinapis arvensis during the development of young floral buds, we performed a genome-wide high-throughput transcriptomic sequencing for young floral buds of sterile and fertile plants. Results In this study, equal amounts of total RNAs taken from young floral buds of sterile and fertile plants were sequenced using the Illumina/Solexa platform. After filtered out low quality data, a total of 2,760,574 and 2,714,441 clean tags were remained in the two libraries, from which 242,163 (Ste) and 253,507 (Fer) distinct tags were obtained. All distinct sequencing tags were annotated using all possible CATG+17-nt sequences of the genome and transcriptome of Brassica rapa and those of Brassica oleracea as the reference sequences, respectively. In total, 3231 genes of B. rapa and 3371 genes of B. oleracea were detected with significant differential expression levels. GO and pathway-based analyses were performed to determine and further to understand the biological functions of those differentially expressed genes (DEGs). In addition, there were 1089 specially expressed unknown tags in Fer, which were neither mapped to B. oleracea nor to B. rapa, and these unique tags were presumed to arise basically from the added alien chromosome of S. arvensis. Fifteen genes were randomly selected and their expression levels were confirmed by quantitative RT-PCR, and fourteen of them showed consistent expression patterns with the digital gene expression (DGE) data. Conclusions A number of genes were differentially expressed between the young floral buds of sterile and fertile plants. Some of these genes may be candidates for future research on CMS in Nsa line, fertility

  8. Community Links

    ERIC Educational Resources Information Center

    Nelson, Mary

    1975-01-01

    At Moraine Valley Community College (Illinois), a chain of events, programs, activities, and services has linked the college and community in such areas as fine arts, ethnic groups, public services, community action, community service, and community education. (Author/NHM)

  9. Link Analysis

    NASA Astrophysics Data System (ADS)

    Donoho, Steve

    Link analysis is a collection of techniques that operate on data that can be represented as nodes and links. This chapter surveys a variety of techniques including subgraph matching, finding cliques and K-plexes, maximizing spread of influence, visualization, finding hubs and authorities, and combining with traditional techniques (classification, clustering, etc). It also surveys applications including social network analysis, viral marketing, Internet search, fraud detection, and crime prevention.

  10. Robot drive mechanism uses conventional electric motors

    NASA Astrophysics Data System (ADS)

    Demchenko, I.

    1986-02-01

    The development and use of three phase asynchronous electric motors in robot technology are presented. The mechanical arm of a robot has as many drives as it has joints. Manipulators in use in modern industry must have six to nine degrees of mobility, and experimental prototypes with 18 coordinates of movement are already developed. A simple, common, and inexpensive industrial electric motor is proposed for use in the robots. This motor was previously considered unsuitable for delicate work because of its low precision in executing commands and the difficulty in controlling it. Control methods were developed to overcome this difficulty. Integrated microcircuits and a power converter control the operation of the single motor. A cassette made up of six units controls the operation of the whole mechanical arm. This cassette is linked with the brain of the robot (a microprocessor system or microcomputer).

  11. Fine motor control

    MedlinePlus

    ... figure out the child's developmental age. Children develop fine motor skills over time, by practicing and being taught. To have fine motor control, children need: Awareness and planning Coordination ...

  12. Chronic motor tic disorder

    MedlinePlus

    Chronic vocal tic disorder; Tic - chronic motor tic disorder ... Chronic motor tic disorder is more common than Tourette syndrome . Chronic tics may be forms of Tourette syndrome. Tics usually start ...

  13. Motor patterns during active electrosensory acquisition

    PubMed Central

    Hofmann, Volker; Geurten, Bart R. H.; Sanguinetti-Scheck, Juan I.; Gómez-Sena, Leonel; Engelmann, Jacob

    2014-01-01

    Motor patterns displayed during active electrosensory acquisition of information seem to be an essential part of a sensory strategy by which weakly electric fish actively generate and shape sensory flow. These active sensing strategies are expected to adaptively optimize ongoing behavior with respect to either motor efficiency or sensory information gained. The tight link between the motor domain and sensory perception in active electrolocation make weakly electric fish like Gnathonemus petersii an ideal system for studying sensory-motor interactions in the form of active sensing strategies. Analyzing the movements and electric signals of solitary fish during unrestrained exploration of objects in the dark, we here present the first formal quantification of motor patterns used by fish during electrolocation. Based on a cluster analysis of the kinematic values we categorized the basic units of motion. These were then analyzed for their associative grouping to identify and extract short coherent chains of behavior. This enabled the description of sensory behavior on different levels of complexity: from single movements, over short behaviors to more complex behavioral sequences during which the kinematics alter between different behaviors. We present detailed data for three classified patterns and provide evidence that these can be considered as motor components of active sensing strategies. In accordance with the idea of active sensing strategies, we found categorical motor patterns to be modified by the sensory context. In addition these motor patterns were linked with changes in the temporal sampling in form of differing electric organ discharge frequencies and differing spatial distributions. The ability to detect such strategies quantitatively will allow future research to investigate the impact of such behaviors on sensing. PMID:24904337

  14. Smart motor technology

    NASA Technical Reports Server (NTRS)

    Packard, D.; Schmitt, D.

    1984-01-01

    Current spacecraft design relies upon microprocessor control; however, motors usually require extensive additional electronic circuitry to interface with these microprocessor controls. An improved control technique that allows a smart brushless motor to connect directly to a microprocessor control system is described. An actuator with smart motors receives a spacecraft command directly and responds in a closed loop control mode. In fact, two or more smart motors can be controlled for synchronous operation.

  15. The Effects of Motor Skill Acquisition on the Development of Intentional Communication.

    ERIC Educational Resources Information Center

    Jones, Hazel A.; Horn, Eva M.; Warren, Steven F.

    1999-01-01

    A study investigated the effects of a neurobehavioral motor intervention on intentional communication development of four children (ages 1 to 3) with neuromotor impairments. Related communication skills linked to motor targets were observed. All subjects increased the use of communication behaviors following implementation of the motor-skill…

  16. Differential expression of molecular motors in the motor cortex of sporadic ALS.

    PubMed

    Pantelidou, Maria; Zographos, Spyros E; Lederer, Carsten W; Kyriakides, Theodore; Pfaffl, Michael W; Santama, Niovi

    2007-06-01

    The molecular mechanisms underlying the selective neurodegeneration of motor neurons in amyotrophic lateral sclerosis (ALS) are inadequately understood. Recent breakthroughs have implicated impaired axonal transport, mediated by molecular motors, as a key element for disease onset and progression. The current work identifies the expression of 15 kinesin-like motors in healthy human motor cortex, including three novel isoforms. Our comprehensive quantitative mRNA analysis in control and sporadic ALS (SALS) motor cortex specimens detects SALS-specific down-regulation of KIF1Bbeta and novel KIF3Abeta, two isoforms we show to be enriched in the brain, and also of SOD1, a key enzyme linked to familial ALS. This is accompanied by a marked reduction of KIF3Abeta protein levels. In the motor cortex KIF3Abeta localizes in cholinergic neurons, including upper motor neurons. No mutations causing splicing defects or altering protein-coding sequences were identified in the genes of the three proteins. The present study implicates two motor proteins as possible candidates in SALS pathology. PMID:17418584

  17. Solid propellant motor

    NASA Technical Reports Server (NTRS)

    Shafer, J. I.; Marsh, H. E., Jr. (Inventor)

    1978-01-01

    A case bonded end burning solid propellant rocket motor is described. A propellant with sufficiently low modulus to avoid chamber buckling on cooling from cure and sufficiently high elongation to sustain the stresses induced without cracking is used. The propellant is zone cured within the motor case at high pressures equal to or approaching the pressure at which the motor will operate during combustion. A solid propellant motor with a burning time long enough that its spacecraft would be limited to a maximum acceleration of less than 1 g is provided by one version of the case bonded end burning solid propellant motor of the invention.

  18. Motor/generator

    DOEpatents

    Hickam, Christopher Dale

    2008-05-13

    A motor/generator is provided for connecting between a transmission input shaft and an output shaft of a prime mover. The motor/generator may include a motor/generator housing, a stator mounted to the motor/generator housing, a rotor mounted at least partially within the motor/generator housing and rotatable about a rotor rotation axis, and a transmission-shaft coupler drivingly coupled to the rotor. The transmission-shaft coupler may include a clamp, which may include a base attached to the rotor and a plurality of adjustable jaws.

  19. Motor degradation prediction methods

    SciTech Connect

    Arnold, J.R.; Kelly, J.F.; Delzingaro, M.J.

    1996-12-01

    Motor Operated Valve (MOV) squirrel cage AC motor rotors are susceptible to degradation under certain conditions. Premature failure can result due to high humidity/temperature environments, high running load conditions, extended periods at locked rotor conditions (i.e. > 15 seconds) or exceeding the motor`s duty cycle by frequent starts or multiple valve stroking. Exposure to high heat and moisture due to packing leaks, pressure seal ring leakage or other causes can significantly accelerate the degradation. ComEd and Liberty Technologies have worked together to provide and validate a non-intrusive method using motor power diagnostics to evaluate MOV rotor condition and predict failure. These techniques have provided a quick, low radiation dose method to evaluate inaccessible motors, identify degradation and allow scheduled replacement of motors prior to catastrophic failures.

  20. Motorized support jack

    DOEpatents

    Haney, Steven J.; Herron, Donald Joe

    2001-01-01

    A compact, vacuum compatible motorized jack for supporting heavy loads and adjusting their positions is provided. The motorized jack includes: (a) a housing having a base; (b) a first roller device that provides a first slidable surface and that is secured to the base; (c) a second roller device that provides a second slidable surface and that has an upper surface; (d) a wedge that is slidably positioned between the first roller device and the second roller device so that the wedge is in contact with the first slidable surface and the second slidable surface; (e) a motor; and (d) a drive mechanism that connects the motor and the wedge to cause the motor to controllably move the wedge forwards or backwards. Individual motorized jacks can support and lift of an object at an angle. Two or more motorized jacks can provide tip, tilt and vertical position adjustment capabilities.

  1. Motorized support jack

    DOEpatents

    Haney, Steven J.; Herron, Donald Joe

    2003-05-13

    A compact, vacuum compatible motorized jack for supporting heavy loads and adjusting their positions is provided. The motorized jack includes: (a) a housing having a base; (b) a first roller device that provides a first slidable surface and that is secured to the base; (c) a second roller device that provides a second slidable surface and that has an upper surface; (d) a wedge that is slidably positioned between the first roller device and the second roller device so that the wedge is in contact with the first slidable surface and the second slidable surface; (e) a motor; and (d) a drive mechanism that connects the motor and the wedge to cause the motor to controllably move the wedge forwards or backwards. Individual motorized jacks can support and lift of an object at an angle. Two or more motorized jacks can provide tip, tilt and vertical position adjustment capabilities.

  2. Linked Systems.

    ERIC Educational Resources Information Center

    Association of Research Libraries, Washington, DC.

    Three papers are compiled here for research library directors: (1) "Background: Open Systems Interconnection," in which David F. Bishop provides fundamental background information to explain the concept of the emerging technology of linked systems and open systems interconnection--i.e., an agreed upon standard set of conventions or rules that,…

  3. Measuring collective transport by defined numbers of processive and nonprocessive kinesin motors

    PubMed Central

    Furuta, Ken’ya; Furuta, Akane; Toyoshima, Yoko Y.; Amino, Misako; Oiwa, Kazuhiro; Kojima, Hiroaki

    2013-01-01

    Intracellular transport is thought to be achieved by teams of motor proteins bound to a cargo. However, the coordination within a team remains poorly understood as a result of the experimental difficulty in controlling the number and composition of motors. Here, we developed an experimental system that links together defined numbers of motors with defined spacing on a DNA scaffold. By using this system, we linked multiple molecules of two different types of kinesin motors, processive kinesin-1 or nonprocessive Ncd (kinesin-14), in vitro. Both types of kinesins markedly increased their processivities with motor number. Remarkably, despite the poor processivity of individual Ncd motors, the coupling of two Ncd motors enables processive movement for more than 1 μm along microtubules (MTs). This improvement was further enhanced with decreasing spacing between motors. Force measurements revealed that the force generated by groups of Ncd is additive when two to four Ncd motors work together, which is much larger than that generated by single motors. By contrast, the force of multiple kinesin-1s depends only weakly on motor number. Numerical simulations and single-molecule unbinding measurements suggest that this additive nature of the force exerted by Ncd relies on fast MT binding kinetics and the large drag force of individual Ncd motors. These features would enable small groups of Ncd motors to crosslink MTs while rapidly modulating their force by forming clusters. Thus, our experimental system may provide a platform to study the collective behavior of motor proteins from the bottom up. PMID:23267076

  4. Anosognosia for Motor Impairment Following Left Brain Damage

    PubMed Central

    Cocchini, Gianna; Beschin, Nicoletta; Cameron, Annette; Fotopoulou, Aikaterini; Sala, Sergio Della

    2009-01-01

    Anosognosia for motor impairment has been linked to lesions of the right hemisphere. However, left hemisphere damaged patients have often been excluded from investigation because of their associated language deficits. In this study we assessed anosognosia for motor disorders in a group of left hemisphere damaged patients using 2 tools that assess the presence of unawareness—a structured interview that is a common method of assessment of anosognosia in clinical settings, and a new tool, the Visual-Analogue Test for Anosognosia for Motor Impairment (VATAm; Della Sala, Cocchini, Beschin, & Cameron, in press). The structured interview relies heavily on language and enquires about general motor ability whereas the VATAm is less dependent on language abilities and enquires about specific motor tasks. Results suggest that the frequency of anosognosia in left brain damaged patients may have been underestimated due to methodological reasons, and that anosognosia for motor impairment can also be associated with lesions of the left hemisphere. PMID:19254095

  5. Apollo's curse: neurological causes of motor impairments in musicians.

    PubMed

    Altenmüller, Eckart; Ioannou, Christos I; Lee, Andre

    2015-01-01

    Performing music at a professional level is probably one of the most complex human accomplishments. Extremely fast and complex, temporo-spatially predefined movement patterns have to be learned, memorized, and retrieved with high reliability in order to meet the expectations of listeners. Performing music requires not only the integration of multimodal sensory and motor information, and its precise monitoring via auditory and kinesthetic feedback, but also emotional communicative skills, which provide a "speaking" rendition of a musical masterpiece. To acquire these specialized auditory-sensory-motor and emotional skills, musicians must undergo extensive training periods over many years, which start in early childhood and continue on through stages of increasing physical and strategic complexities. Performance anxiety, linked to high societal pressures such as the fear of failure and heightened self-demands, frequently accompanies these learning processes. Motor disturbances in musicians are common and include mild forms, such as temporary motor fatigue with short-term reduction of motor skills, painful overuse injuries following prolonged practice, anxiety-related motor failures during performances (choking under pressure), as well as more persistent losses of motor control, here termed "dynamic stereotypes" (DSs). Musician's dystonia (MD), which is characterized by the permanent loss of control of highly skilled movements when playing a musical instrument, is the gravest manifestation of dysfunctional motor programs, frequently linked to a genetic susceptibility to develop such motor disturbances. In this review chapter, we focus on different types of motor failures in musicians. We argue that motor failures in musicians develop along a continuum, starting with subtle transient degradations due to fatigue, overuse, or performance stress, which transform by and by into more permanent, still fluctuating motor degradations, the DSs, until a more irreversible

  6. Piezoelectric Motors and Transformers

    NASA Astrophysics Data System (ADS)

    Uchino, K.

    Piezoelectric ceramics forms a new field between electronic and structural ceramics [1-4]. Application fields are classified into three categories: positioners, motors, and vibration suppressors. From the market research result for 80 Japanese component industries in 1992, tiny motors in the range of 5-8 mm are required in large numbers for office and portable equipment; the conventional electromagnetic (EM) motors are rather difficult to produce in this size with sufficient energy efficiency, while Silicon MEMS actuators are too small to be used in practice. Piezoelectric ultrasonic motors whose efficiency is insensitive to size are superior in the millimeter motor area. The manufacturing precision of optical instruments such as lasers and cameras, and the positioning accuracy for fabricating semiconductor chips are of the order of 0.1μm which is much smaller than the backlash of the EM motors. Vibration suppression in space structures and military vehicles also require compact but mighty piezoelectric actuators.

  7. Multifocal motor neuropathy.

    PubMed

    Muley, Suraj Ashok; Parry, Gareth J

    2012-09-01

    Multifocal motor neuropathy (MMN) was first described in 1988 as a purely motor neuropathy affecting multiple motor nerves. The diagnosis was based entirely on demonstrating electrophysiological evidence of a conduction block (CB) that selectively affected motor axons, with sparing of sensory axons even through the site of motor CB. Subsequently, a similar disorder was reported but with absence of demonstrable CB on routine nerve conduction studies and there is still some debate as to whether MMN without CB is related to MMN. MMN is thought to be an inflammatory neuropathy related to an immune attack on motor nerves. The conventional hypothesis is that the primary pathology is segmental demyelination, but recent research raises the possibility of a primary axonopathy. Anti-GM1 antibodies can be found in some patients but it is unclear whether these antibodies are pathogenic. Intravenous immunoglobulin is the mainstay of treatment but other immunosuppressive treatments can also be effective. PMID:22743043

  8. Motor Rumblings: Characterization of Adaptation Motors in Saccular Hair Cells by Noise Analysis

    NASA Astrophysics Data System (ADS)

    Frank, Jonathan E.; Markin, Vladislav; Jaramillo, Fernán

    2003-05-01

    The mechanical sensitivity of hair cells, the sensory receptors of the vestibular and auditory systems, is maintained by adaptation, which resets the transducer to cancel the effects of static stimuli. One model of adaptation proposes that myosin motors coupled to transduction channels move along the long axis of the hair bundle's stereocilia, to regulate the tension in the tip links which are thought to gate transduction channels [1, 2]. These motors can be activated by applying a transduction channel blocker to the bundle, causing it to move [3, 4]. We studied the variance in the position of the bundle during these displacements, and found that it increases as the bundle moves to its new position. We can explain both displacement and variance with a simple model in which a single motor acting on the bundle takes ˜3.6 nm steps whose frequency declines with the motor's load.

  9. Auditory-Perceptual Learning Improves Speech Motor Adaptation in Children

    PubMed Central

    Shiller, Douglas M.; Rochon, Marie-Lyne

    2015-01-01

    Auditory feedback plays an important role in children’s speech development by providing the child with information about speech outcomes that is used to learn and fine-tune speech motor plans. The use of auditory feedback in speech motor learning has been extensively studied in adults by examining oral motor responses to manipulations of auditory feedback during speech production. Children are also capable of adapting speech motor patterns to perceived changes in auditory feedback, however it is not known whether their capacity for motor learning is limited by immature auditory-perceptual abilities. Here, the link between speech perceptual ability and the capacity for motor learning was explored in two groups of 5–7-year-old children who underwent a period of auditory perceptual training followed by tests of speech motor adaptation to altered auditory feedback. One group received perceptual training on a speech acoustic property relevant to the motor task while a control group received perceptual training on an irrelevant speech contrast. Learned perceptual improvements led to an enhancement in speech motor adaptation (proportional to the perceptual change) only for the experimental group. The results indicate that children’s ability to perceive relevant speech acoustic properties has a direct influence on their capacity for sensory-based speech motor adaptation. PMID:24842067

  10. Collective Dynamics of Elastically Coupled Myosin V Motors*

    PubMed Central

    Lu, Hailong; Efremov, Artem K.; Bookwalter, Carol S.; Krementsova, Elena B.; Driver, Jonathan W.; Trybus, Kathleen M.; Diehl, Michael R.

    2012-01-01

    Characterization of the collective behaviors of different classes of processive motor proteins has become increasingly important to understand various intracellular trafficking and transport processes. This work examines the dynamics of structurally-defined motor complexes containing two myosin Va (myoVa) motors that are linked together via a molecular scaffold formed from a single duplex of DNA. Dynamic changes in the filament-bound configuration of these complexes due to motor binding, stepping, and detachment were monitored by tracking the positions of different color quantum dots that report the position of one head of each myoVa motor on actin. As in studies of multiple kinesins, the run lengths produced by two myosins are only slightly larger than those of single motor molecules. This suggests that internal strain within the complexes, due to asynchronous motor stepping and the resultant stretching of motor linkages, yields net negative cooperative behaviors. In contrast to multiple kinesins, multiple myosin complexes move with appreciably lower velocities than a single-myosin molecule. Although similar trends are predicted by a discrete state stochastic model of collective motor dynamics, these analyses also suggest that multiple myosin velocities and run lengths depend on both the compliance and the effective size of their cargo. Moreover, it is proposed that this unique collective behavior occurs because the large step size and relatively small stalling force of myoVa leads to a high sensitivity of motor stepping rates to strain. PMID:22718762

  11. Maladaptive Plasticity for Motor Recovery after Stroke: Mechanisms and Approaches

    PubMed Central

    Takeuchi, Naoyuki; Izumi, Shin-Ichi

    2012-01-01

    Many studies in human and animal models have shown that neural plasticity compensates for the loss of motor function after stroke. However, neural plasticity concerning compensatory movement, activated ipsilateral motor projections and competitive interaction after stroke contributes to maladaptive plasticity, which negatively affects motor recovery. Compensatory movement on the less-affected side helps to perform self-sustaining activity but also creates an inappropriate movement pattern and ultimately limits the normal motor pattern. The activated ipsilateral motor projections after stroke are unable to sufficiently support the disruption of the corticospinal motor projections and induce the abnormal movement linked to poor motor ability. The competitive interaction between both hemispheres induces abnormal interhemispheric inhibition that weakens motor function in stroke patients. Moreover, widespread disinhibition increases the risk of competitive interaction between the hand and the proximal arm, which results in an incomplete motor recovery. To minimize this maladaptive plasticity, rehabilitation programs should be selected according to the motor impairment of stroke patients. Noninvasive brain stimulation might also be useful for correcting maladaptive plasticity after stroke. Here, we review the underlying mechanisms of maladaptive plasticity after stroke and propose rehabilitation approaches for appropriate cortical reorganization. PMID:22792492

  12. Parametric electric motor study

    SciTech Connect

    Adams, D.; Stahura, D.

    1995-04-30

    Technology for the axial gap motor was developed by DOE with an investment of approximately $15 million. This development effort is for motor technologies of high power density and high efficiency. Such motors that are also small and light-weight are not available on the commercial market because high-power motors have typically been used in large industrial applications where small size and light weight are not requirements. AC Delco has been developing motors since 1918 and is interested in leveraging its research and development dollars to produce an array of motor systems for vehicles and to develop a future line of propulsion products. The DOE focus of the study was applied to machining applications. The most attractive feature of this motor is the axial air gap, which may make possible the removal of the motor`s stationary component from a total enclosure of the remainder of the machine if the power characteristics are adequate. The objectives of this project were to evaluate alternative electric drive systems for machine tools and automotive electric drive systems and to select a best machine type for each of those applications. A major challenge of this project was to produce a small, light-weight, highly efficient motor at a cost-effective price. The project developed machine and machine drive systems and design criteria for the range of applications. The final results included the creation of a baseline for developing electric vehicle powertrain system designs, conventional vehicle engine support system designs, and advanced machine tool configurations. In addition, an axial gap permanent magnet motor was built and tested, and gave, said one engineer involved, a sterling performance. This effort will commercialize advanced motor technology and extend knowledge and design capability in the most efficient electric machine design known today.

  13. Hybrid vehicle motor alignment

    DOEpatents

    Levin, Michael Benjamin

    2001-07-03

    A rotor of an electric motor for a motor vehicle is aligned to an axis of rotation for a crankshaft of an internal combustion engine having an internal combustion engine and an electric motor. A locator is provided on the crankshaft, a piloting tool is located radially by the first locator to the crankshaft. A stator of the electric motor is aligned to a second locator provided on the piloting tool. The stator is secured to the engine block. The rotor is aligned to the crankshaft and secured thereto.

  14. Cryogenic Electric Motor Tested

    NASA Technical Reports Server (NTRS)

    Brown, Gerald V.

    2004-01-01

    Technology for pollution-free "electric flight" is being evaluated in a number of NASA Glenn Research Center programs. One approach is to drive propulsive fans or propellers with electric motors powered by fuel cells running on hydrogen. For large transport aircraft, conventional electric motors are far too heavy to be feasible. However, since hydrogen fuel would almost surely be carried as liquid, a propulsive electric motor could be cooled to near liquid hydrogen temperature (-423 F) by using the fuel for cooling before it goes to the fuel cells. Motor windings could be either superconducting or high purity normal copper or aluminum. The electrical resistance of pure metals can drop to 1/100th or less of their room-temperature resistance at liquid hydrogen temperature. In either case, super or normal, much higher current density is possible in motor windings. This leads to more compact motors that are projected to produce 20 hp/lb or more in large sizes, in comparison to on the order of 2 hp/lb for large conventional motors. High power density is the major goal. To support cryogenic motor development, we have designed and built in-house a small motor (7-in. outside diameter) for operation in liquid nitrogen.

  15. A catalytic oligomeric motor that walks along a filament track

    NASA Astrophysics Data System (ADS)

    Huang, Mu-Jie; Kapral, Raymond

    2015-06-01

    Most biological motors in the cell execute chemically powered conformational changes as they walk on biopolymer filaments in order to carry out directed transport functions. Synthetic motors that operate in a similar manner are being studied since they have the potential to perform similar tasks in a variety of applications. In this paper, a synthetic nanomotor that moves along a filament track, without invoking motor conformational changes, is constructed and its properties are studied in detail. The motor is an oligomer comprising three linked beads with specific binding properties. The filament track is a stiff polymer chain, also described by a linear chain of linked coarse-grained molecular groups modeled as beads. Reactions on the filament that are catalyzed by a motor bead and use fuel in the environment, in conjunction within the binding affinities of the motor beads to the filament beads, lead to directed motion. The system operates out of equilibrium due to the state of the filament and supply of fuel. The motor, filament, and surrounding medium are all described at microscopic level that permits a full analysis of the motor motion. A stochastic model that captures the main trends seen in the simulations is also presented. The results of this study point to some of the key features that could be used to construct nanomotors that undergo biased walks powered by chemical reactions on filaments.

  16. A catalytic oligomeric motor that walks along a filament track

    SciTech Connect

    Huang, Mu-Jie Kapral, Raymond

    2015-06-28

    Most biological motors in the cell execute chemically powered conformational changes as they walk on biopolymer filaments in order to carry out directed transport functions. Synthetic motors that operate in a similar manner are being studied since they have the potential to perform similar tasks in a variety of applications. In this paper, a synthetic nanomotor that moves along a filament track, without invoking motor conformational changes, is constructed and its properties are studied in detail. The motor is an oligomer comprising three linked beads with specific binding properties. The filament track is a stiff polymer chain, also described by a linear chain of linked coarse-grained molecular groups modeled as beads. Reactions on the filament that are catalyzed by a motor bead and use fuel in the environment, in conjunction within the binding affinities of the motor beads to the filament beads, lead to directed motion. The system operates out of equilibrium due to the state of the filament and supply of fuel. The motor, filament, and surrounding medium are all described at microscopic level that permits a full analysis of the motor motion. A stochastic model that captures the main trends seen in the simulations is also presented. The results of this study point to some of the key features that could be used to construct nanomotors that undergo biased walks powered by chemical reactions on filaments.

  17. A COMPUTATIONAL MODEL OF MOTOR NEURON DEGENERATION

    PubMed Central

    Le Masson, Gwendal; Przedborski, Serge; Abbott, L.F.

    2014-01-01

    SUMMARY To explore the link between bioenergetics and motor neuron degeneration, we used a computational model in which detailed morphology and ion conductance are paired with intracellular ATP production and consumption. We found that reduced ATP availability increases the metabolic cost of a single action potential and disrupts K+/Na+ homeostasis, resulting in a chronic depolarization. The magnitude of the ATP shortage at which this ionic instability occurs depends on the morphology and intrinsic conductance characteristic of the neuron. If ATP shortage is confined to the distal part of the axon, the ensuing local ionic instability eventually spreads to the whole neuron and involves fasciculation-like spiking events. A shortage of ATP also causes a rise in intracellular calcium. Our modeling work supports the notion that mitochondrial dysfunction can account for salient features of the paralytic disorder amyotrophic lateral sclerosis, including motor neuron hyperexcitability, fasciculation, and differential vulnerability of motor neuron subpopulations. PMID:25088365

  18. Heritability of motor control and motor learning

    PubMed Central

    Missitzi, Julia; Gentner, Reinhard; Misitzi, Angelica; Geladas, Nickos; Politis, Panagiotis; Klissouras, Vassilis; Classen, Joseph

    2013-01-01

    Abstract The aim of this study was to elucidate the relative contribution of genes and environment on individual differences in motor control and acquisition of a force control task, in view of recent association studies showing that several candidate polymorphisms may have an effect on them. Forty‐four healthy female twins performed brisk isometric abductions with their right thumb. Force was recorded by a transducer and fed back to the subject on a computer screen. The task was to place the tracing of the peak force in a force window defined between 30% and 40% of the subject's maximum force, as determined beforehand. The initial level of proficiency was defined as the number of attempts reaching the force window criterion within the first 100 trials. The difference between the number of successful trials within the last and the first 100 trials was taken as a measure of motor learning. For motor control, defined by the initial level of proficiency, the intrapair differences in monozygotic (MZ) and dizygotic (DZ) twins were 6.8 ± 7.8 and 13.8 ± 8.4, and the intrapair correlations 0.77 and 0.39, respectively. Heritability was estimated at 0.68. Likewise for motor learning intrapair differences in the increment of the number of successful trials in MZ and DZ twins were 5.4 ± 5.2 and 12.8 ± 7, and the intrapair correlations 0.58 and 0.19. Heritability reached 0.70. The present findings suggest that heredity accounts for a major part of existing differences in motor control and motor learning, but uncertainty remains which gene polymorphisms may be responsible. PMID:24744865

  19. Motor Vehicle Safety

    MedlinePlus

    ... from motor vehicle crashes. Trying to prevent these crashes is one part of motor vehicle safety. Here are some things you can do to be safer on the road: Make sure your vehicle is safe and in working order Use car seats for children Wear your seat belt Don' ...

  20. Stepping motor controller

    DOEpatents

    Bourret, S.C.; Swansen, J.E.

    1982-07-02

    A stepping motor is microprocessor controlled by digital circuitry which monitors the output of a shaft encoder adjustably secured to the stepping motor and generates a subsequent stepping pulse only after the preceding step has occurred and a fixed delay has expired. The fixed delay is variable on a real-time basis to provide for smooth and controlled deceleration.

  1. Stepping motor controller

    DOEpatents

    Bourret, Steven C.; Swansen, James E.

    1984-01-01

    A stepping motor is microprocessingly controlled by digital circuitry which monitors the output of a shaft encoder adjustably secured to the stepping motor and generates a subsequent stepping pulse only after the preceding step has occurred and a fixed delay has expired. The fixed delay is variable on a real-time basis to provide for smooth and controlled deceleration.

  2. Hybrid Rocket Motor Test

    NASA Technical Reports Server (NTRS)

    1994-01-01

    A 10,000-pound thrust hybrid rocket motor is tested at Stennis Space Center's E-1 test facility. A hybrid rocket motor is a cross between a solid rocket and a liquid-fueled engine. It uses environmentally safe solid fuel and liquid oxygen.

  3. Organizing motor imageries.

    PubMed

    Hanakawa, Takashi

    2016-03-01

    Over the last few decades, motor imagery has attracted the attention of researchers as a prototypical example of 'embodied cognition' and also as a basis for neuro-rehabilitation and brain-machine interfaces. The current definition of motor imagery is widely accepted, but it is important to note that various abilities rather than a single cognitive entity are dealt with under a single term. Here, motor imagery has been characterized based on four factors: (1) motor control, (2) explicitness, (3) sensory modalities, and (4) agency. Sorting out these factors characterizing motor imagery may explain some discrepancies and variability in the findings from previous studies and will help to optimize a study design in accordance with the purpose of each study in the future. PMID:26602980

  4. Induction motor control

    NASA Technical Reports Server (NTRS)

    Hansen, Irving G.

    1990-01-01

    Electromechanical actuators developed to date have commonly utilized permanent magnet (PM) synchronous motors. More recently switched reluctance (SR) motors have been advocated due to their robust characteristics. Implications of work which utilizes induction motors and advanced control techniques are discussed. When induction motors are operated from an energy source capable of controlling voltages and frequencies independently, drive characteristics are obtained which are superior to either PM or SR motors. By synthesizing the machine frequency from a high frequency carrier (nominally 20 kHz), high efficiencies, low distortion, and rapid torque response are available. At this time multiple horsepower machine drives were demonstrated, and work is on-going to develop a 20 hp average, 40 hp peak class of aerospace actuators. This effort is based upon high frequency power distribution and management techniques developed by NASA for Space Station Freedom.

  5. Induction motor control

    NASA Technical Reports Server (NTRS)

    Hansen, Irving G.

    1990-01-01

    Electromechanical actuators developed to date have commonly ultilized permanent magnet (PM) synchronous motors. More recently switched reluctance (SR) motors have been advocated due to their robust characteristics. Implications of work which utilized induction motors and advanced control techniques are discussed. When induction motors are operated from an energy source capable of controlling voltages and frequencies independently, drive characteristics are obtained which are superior to either PM or SR motors. By synthesizing the machine frequency from a high-frequency carrier (nominally 20 kHz), high efficiencies, low distortion, and rapid torque response are available. At this time multiple horsepower machine drives were demonstrated, and work is on-going to develop a 20 hp average, 40 hp peak class of aerospace actuators. This effort is based upon high-frequency power distribution and management techniques developed by NASA for Space Station Freedom.

  6. Induction motor control

    NASA Astrophysics Data System (ADS)

    Hansen, Irving G.

    Electromechanical actuators developed to date have commonly ultilized permanent magnet (PM) synchronous motors. More recently switched reluctance (SR) motors have been advocated due to their robust characteristics. Implications of work which utilized induction motors and advanced control techniques are discussed. When induction motors are operated from an energy source capable of controlling voltages and frequencies independently, drive characteristics are obtained which are superior to either PM or SR motors. By synthesizing the machine frequency from a high-frequency carrier (nominally 20 kHz), high efficiencies, low distortion, and rapid torque response are available. At this time multiple horsepower machine drives were demonstrated, and work is on-going to develop a 20 hp average, 40 hp peak class of aerospace actuators. This effort is based upon high-frequency power distribution and management techniques developed by NASA for Space Station Freedom.

  7. Transatlantic link

    NASA Astrophysics Data System (ADS)

    (left) European Geophysical Society (EGS) President Rolf Meissner at AGU Headquarters with (center) Executive Director Fred Spilhaus and (right) Foreign Secretary Juan Roederer. Meissner attended the meeting of AGU's Committee on International Participation (CIP) on February 26, 1988. At that meeting, specific ways of fostering close links between AGU and EGS were discussed.A few weeks later, Roederer and AGU staff, working with EGS Secretary-General Arne Richter at the EGS meeting in Bologna, Italy, March 21-25, planned details of the establishment of an AGU office in Europe. The Copernicus Gesellschaft, a new entity located on the premises of the Max Planck Institute for Aeronomy in Lindau, Federal Republic of Germany, will provide the administrative staff and handle logistics.

  8. ncd and kinesin motor domains interact with both alpha- and beta-tubulin.

    PubMed Central

    Walker, R A

    1995-01-01

    Motor domains of the Drosophila minus-end-directed microtubule (MT) motor protein ncd, were found to saturate microtubule binding sites at a stoichiometry of approximately one motor domain per tubulin dimer. To determine the tubulin subunit(s) involved in binding to ncd, mixtures of ncd motor domain and MTs were treated with the zero-length cross-linker 1-ethyl-3-(3-dimethylaminopropyl-carbodiimide) (EDC). EDC treatment generated covalently cross-linked products of ncd and alpha-tubulin and of ncd and beta-tubulin, indicating that the ncd motor domain interacts with both alpha- and beta-tubulin. When the Drosophila kinesin motor domain protein was substituted for the ncd motor domain, cross-linked products of kinesin and alpha-tubulin and of kinesin and beta-tubulin were produced. EDC treatment of mixtures of ncd motor domain and unassembled tubulin dimers or of kinesin motor domain and unassembled tubulin dimers produced the same motor-tubulin products generated in the presence of MTs. These results indicate that kinesin family motors of opposite polarity interact with both tubulin monomers and support a model in which some portion of each protein's motor domain overlaps adjacent alpha- and beta-tubulin subunits. Images Fig. 2 Fig. 3 Fig. 4 Fig. 5 PMID:7597061

  9. Motor Priming in Neurorehabilitation

    PubMed Central

    Stoykov, Mary Ellen; Madhavan, Sangeetha

    2014-01-01

    Priming is a type of implicit learning wherein a stimulus prompts a change in behavior. Priming has been long studied in the field of psychology. More recently, rehabilitation researchers have studied motor priming as a possible way to facilitate motor learning. For example, priming of the motor cortex is associated with changes in neuroplasticity that are associated with improvements in motor performance. Of the numerous motor priming paradigms under investigation, only a few are practical for the current clinical environment, and the optimal priming modalities for specific clinical presentations are not known. Accordingly, developing an understanding of the various types of motor priming paradigms and their underlying neural mechanisms is an important step for therapists in neurorehabilitation. Most importantly, an understanding of the methods and their underlying mechanisms is essential for optimizing rehabilitation outcomes. The future of neurorehabilitation is likely to include these priming methods, which are delivered prior to or in conjunction with primary neurorehabilitation therapies. In this Special Interest article we discuss those priming paradigms that are supported by the greatest amount of evidence including: (i) stimulation-based priming, (ii) motor imagery and action observation, (iii) sensory priming, (iv) movement-based priming, and (v) pharmacological priming. PMID:25415551

  10. The induction motor

    NASA Astrophysics Data System (ADS)

    Redinz, José Arnaldo

    2015-09-01

    We obtain analytical expressions for the torques and angular speed of an induction motor with a simple geometry, resembling the geometry of the first induction motor investigated by Arago in 1824. The rotor is a conducting disc rotating between the magnetic poles of two off-axis solenoids, displaced in space by 90^\\circ from each other. We apply our results to discuss a theory for the ubiquitous electromechanical watt-hour meter. For comparison of the theoretical result for the angular speed with measurements, we propose a simple experiment in which an induction motor with an aluminum disc rotor is constructed.

  11. Relations among motor, social, and cognitive skills in pre-kindergarten children with developmental disabilities.

    PubMed

    Kim, Helyn; Carlson, Abby G; Curby, Timothy W; Winsler, Adam

    2016-01-01

    Despite the comorbidity between motor difficulties and certain disabilities, limited research has examined links between early motor, cognitive, and social skills in preschool-aged children with developmental disabilities. The present study examined the relative contributions of gross motor and fine motor skills to the prediction of improvements in children's cognitive and social skills among 2,027 pre-kindergarten children with developmental disabilities, including specific learning disorder, speech/language impairment, intellectual disability, and autism spectrum disorder. Results indicated that for pre-kindergarten children with developmental disabilities, fine motor skills, but not gross motor skills, were predictive of improvements in cognitive and social skills, even after controlling for demographic information and initial skill levels. Moreover, depending on the type of developmental disability, the pattern of prediction of gross motor and fine motor skills to improvements in children's cognitive and social skills differed. Implications are discussed. PMID:26852279

  12. Role of the motor system in language knowledge.

    PubMed

    Berent, Iris; Brem, Anna-Katharine; Zhao, Xu; Seligson, Erica; Pan, Hong; Epstein, Jane; Stern, Emily; Galaburda, Albert M; Pascual-Leone, Alvaro

    2015-02-17

    All spoken languages express words by sound patterns, and certain patterns (e.g., blog) are systematically preferred to others (e.g., lbog). What principles account for such preferences: does the language system encode abstract rules banning syllables like lbog, or does their dislike reflect the increased motor demands associated with speech production? More generally, we ask whether linguistic knowledge is fully embodied or whether some linguistic principles could potentially be abstract. To address this question, here we gauge the sensitivity of English speakers to the putative universal syllable hierarchy (e.g., blif ≻ bnif ≻ bdif ≻ lbif) while undergoing transcranial magnetic stimulation (TMS) over the cortical motor representation of the left orbicularis oris muscle. If syllable preferences reflect motor simulation, then worse-formed syllables (e.g., lbif) should (i) elicit more errors; (ii) engage more strongly motor brain areas; and (iii) elicit stronger effects of TMS on these motor regions. In line with the motor account, we found that repetitive TMS pulses impaired participants' global sensitivity to the number of syllables, and functional MRI confirmed that the cortical stimulation site was sensitive to the syllable hierarchy. Contrary to the motor account, however, ill-formed syllables were least likely to engage the lip sensorimotor area and they were least impaired by TMS. Results suggest that speech perception automatically triggers motor action, but this effect is not causally linked to the computation of linguistic structure. We conclude that the language and motor systems are intimately linked, yet distinct. Language is designed to optimize motor action, but its knowledge includes principles that are disembodied and potentially abstract. PMID:25646465

  13. Role of the motor system in language knowledge

    PubMed Central

    Berent, Iris; Brem, Anna-Katharine; Zhao, Xu; Seligson, Erica; Pan, Hong; Epstein, Jane; Stern, Emily; Galaburda, Albert M.; Pascual-Leone, Alvaro

    2015-01-01

    All spoken languages express words by sound patterns, and certain patterns (e.g., blog) are systematically preferred to others (e.g., lbog). What principles account for such preferences: does the language system encode abstract rules banning syllables like lbog, or does their dislike reflect the increased motor demands associated with speech production? More generally, we ask whether linguistic knowledge is fully embodied or whether some linguistic principles could potentially be abstract. To address this question, here we gauge the sensitivity of English speakers to the putative universal syllable hierarchy (e.g., blif≻bnif≻bdif≻lbif) while undergoing transcranial magnetic stimulation (TMS) over the cortical motor representation of the left orbicularis oris muscle. If syllable preferences reflect motor simulation, then worse-formed syllables (e.g., lbif) should (i) elicit more errors; (ii) engage more strongly motor brain areas; and (iii) elicit stronger effects of TMS on these motor regions. In line with the motor account, we found that repetitive TMS pulses impaired participants’ global sensitivity to the number of syllables, and functional MRI confirmed that the cortical stimulation site was sensitive to the syllable hierarchy. Contrary to the motor account, however, ill-formed syllables were least likely to engage the lip sensorimotor area and they were least impaired by TMS. Results suggest that speech perception automatically triggers motor action, but this effect is not causally linked to the computation of linguistic structure. We conclude that the language and motor systems are intimately linked, yet distinct. Language is designed to optimize motor action, but its knowledge includes principles that are disembodied and potentially abstract. PMID:25646465

  14. Microtubule patterning in the presence of stationary motor distributions.

    PubMed

    White, Diana; de Vries, Gerda; Dawes, Adriana

    2014-08-01

    In this paper, we construct a novel nonlocal transport model that describes the evolution of microtubules (MTs) as they interact with stationary distributions of motor proteins. An advection term accounts for directed MT transport (sliding due to motor protein action), and an integral term accounts for reorientation of MTs due to their interactions with cross-linking motor proteins. Simulations of our model show how MT patterns depend on boundary constraints, as well as model parameters that represent motor speed, cross-linking capability (motor activity), and directionality. In large domains, and using motor parameter values consistent with experimentally-derived values, we find that patterns such as asters, vortices, and bundles are able to persist. In vivo, MTs take on aster patterns during interphase and they form bundles in neurons and polarized epithelial cells. Vortex patterns have not been observed in vivo, however, are found in in vitro experiments. In constrained domains, we find that similar patterns form (asters, bundles, and vortices). However, we also find that when two opposing motors are present, anti-parallel bundles are able to form, resembling the mitotic spindle during cell division. This model demonstrates how MT sliding and MT reorientation are sufficient to produce experimentally observed patterns. PMID:25033782

  15. System and method for motor parameter estimation

    SciTech Connect

    Luhrs, Bin; Yan, Ting

    2014-03-18

    A system and method for determining unknown values of certain motor parameters includes a motor input device connectable to an electric motor having associated therewith values for known motor parameters and an unknown value of at least one motor parameter. The motor input device includes a processing unit that receives a first input from the electric motor comprising values for the known motor parameters for the electric motor and receive a second input comprising motor data on a plurality of reference motors, including values for motor parameters corresponding to the known motor parameters of the electric motor and values for motor parameters corresponding to the at least one unknown motor parameter value of the electric motor. The processor determines the unknown value of the at least one motor parameter from the first input and the second input and determines a motor management strategy for the electric motor based thereon.

  16. Disentangling Fine Motor Skills' Relations to Academic Achievement: The Relative Contributions of Visual-Spatial Integration and Visual-Motor Coordination

    ERIC Educational Resources Information Center

    Carlson, Abby G.; Rowe, Ellen; Curby, Timothy W.

    2013-01-01

    Recent research has established a connection between children's fine motor skills and their academic performance. Previous research has focused on fine motor skills measured prior to elementary school, while the present sample included children ages 5-18 years old, making it possible to examine whether this link remains relevant throughout…

  17. Piezoelectric Rotary Tube Motor

    NASA Technical Reports Server (NTRS)

    Fisher, Charles D.; Badescu, Mircea; Braun, David F.; Culhane, Robert

    2011-01-01

    A custom rotary SQUIGGLE(Registered TradeMark) motor has been developed that sets new benchmarks for small motor size, high position resolution, and high torque without gear reduction. Its capabilities cannot be achieved with conventional electromagnetic motors. It consists of piezoelectric plates mounted on a square flexible tube. The plates are actuated via voltage waveforms 90 out of phase at the resonant frequency of the device to create rotary motion. The motors were incorporated into a two-axis postioner that was designed for fiber-fed spectroscopy for ground-based and space-based projects. The positioner enables large-scale celestial object surveys to take place in a practical amount of time.

  18. Hybrid Rocket Motor Test

    NASA Technical Reports Server (NTRS)

    1994-01-01

    Stennis Space Center conducts a test on a hybrid rocket motor fed by a liquid oxygen turbopump. The test occurred at the E-1 test facility. The test was believed to be the first of its kind in the world.

  19. Chronic motor tic disorder

    MedlinePlus

    Chronic motor tic disorder is more common than Tourette syndrome . Chronic tics may be forms of Tourette syndrome. Tics usually start at age 5 or 6 and get worse until age 12. They often improve during adulthood.

  20. Motor Vehicle Safety

    MedlinePlus

    ... these crashes is one part of motor vehicle safety. Here are some things you can do to ... speed or drive aggressively Don't drive impaired Safety also involves being aware of others. Share the ...

  1. MotorWeek

    ScienceCinema

    None

    2013-04-19

    In 2008, PBS's MotorWeek, television's original automotive magazine, visited Argonne's Transportation Technology R&D Center "to learn what it really takes to make clean power sources a viable reality."

  2. MotorWeek

    SciTech Connect

    2009-01-01

    In 2008, PBS's MotorWeek, television's original automotive magazine, visited Argonne's Transportation Technology R&D Center "to learn what it really takes to make clean power sources a viable reality."

  3. Booster separation motor

    NASA Technical Reports Server (NTRS)

    1981-01-01

    The design, development, fabrication, testing, evaluation and flight qualification of the space shuttle booster separation motor is discussed. Delivery of flight hardware to support the research and development flights of the space shuttle is discussed.

  4. High Power Density Motors

    NASA Technical Reports Server (NTRS)

    Kascak, Daniel J.

    2004-01-01

    With the growing concerns of global warming, the need for pollution-free vehicles is ever increasing. Pollution-free flight is one of NASA's goals for the 21" Century. , One method of approaching that goal is hydrogen-fueled aircraft that use fuel cells or turbo- generators to develop electric power that can drive electric motors that turn the aircraft's propulsive fans or propellers. Hydrogen fuel would likely be carried as a liquid, stored in tanks at its boiling point of 20.5 K (-422.5 F). Conventional electric motors, however, are far too heavy (for a given horsepower) to use on aircraft. Fortunately the liquid hydrogen fuel can provide essentially free refrigeration that can be used to cool the windings of motors before the hydrogen is used for fuel. Either High Temperature Superconductors (HTS) or high purity metals such as copper or aluminum may be used in the motor windings. Superconductors have essentially zero electrical resistance to steady current. The electrical resistance of high purity aluminum or copper near liquid hydrogen temperature can be l/lOO* or less of the room temperature resistance. These conductors could provide higher motor efficiency than normal room-temperature motors achieve. But much more importantly, these conductors can carry ten to a hundred times more current than copper conductors do in normal motors operating at room temperature. This is a consequence of the low electrical resistance and of good heat transfer coefficients in boiling LH2. Thus the conductors can produce higher magnetic field strengths and consequently higher motor torque and power. Designs, analysis and actual cryogenic motor tests show that such cryogenic motors could produce three or more times as much power per unit weight as turbine engines can, whereas conventional motors produce only 1/5 as much power per weight as turbine engines. This summer work has been done with Litz wire to maximize the current density. The current is limited by the amount of heat it

  5. Motor Energy Conservation Measures

    Energy Science and Technology Software Center (ESTSC)

    2010-12-31

    This software requires inputs of simple motor inventory information and calculates the energy and cost benefits of various retrofit opportunities. This tool includes energy conservation measures for: High Efficiency Motor retrofit and Cogged V-belts retrofit. This tool calculates energy savings, demand reduction, cost savings, and building life cycle costs including: simple payback, discounted payback, net-present value, and savings to investment ratio. In addition this tool also displays the environmental benefits of a project.

  6. Rocket Motor Microphone Investigation

    NASA Technical Reports Server (NTRS)

    Pilkey, Debbie; Herrera, Eric; Gee, Kent L.; Giraud, Jerom H.; Young, Devin J.

    2010-01-01

    At ATK's facility in Utah, large full-scale solid rocket motors are tested. The largest is a five-segment version of the reusable solid rocket motor, which is for use on the Ares I launch vehicle. As a continuous improvement project, ATK and BYU investigated the use of microphones on these static tests, the vibration and temperature to which the instruments are subjected, and in particular the use of vent tubes and the effects these vents have at low frequencies.

  7. Electric vehicle motors and controllers

    NASA Technical Reports Server (NTRS)

    Secunde, R. R.

    1981-01-01

    Improved and advanced components being developed include electronically commutated permanent magnet motors of both drum and disk configuration, an unconventional brush commutated motor, and ac induction motors and various controllers. Test results on developmental motors, controllers, and combinations thereof indicate that efficiencies of 90% and higher for individual components, and 80% to 90% for motor/controller combinations can be obtained at rated power. The simplicity of the developmental motors and the potential for ultimately low cost electronics indicate that one or more of these approaches to electric vehicle propulsion may eventually displace presently used controllers and brush commutated dc motors.

  8. Robust transport by multiple motors with nonlinear force-velocity relations and stochastic load sharing

    NASA Astrophysics Data System (ADS)

    Kunwar, Ambarish; Mogilner, Alexander

    2010-03-01

    Transport by processive molecular motors plays an important role in many cell biological phenomena. In many cases, motors work together to transport cargos in the cell, so it is important to understand the mechanics of the multiple motors. Based on earlier modeling efforts, here we study effects of nonlinear force-velocity relations and stochastic load sharing on multiple motor transport. We find that when two or three motors transport the cargo, then the nonlinear and stochastic effects compensate so that the mechanical properties of the transport are robust. Similarly, the transport is insensitive to compliance of the cargo-motor links. Furthermore, the rate of movement against moderate loads is not improved by increasing the small number of motors. When the motor number is greater than 4, correlations between the motors become negligible, and the earlier analytical mean-field theory of the multiple motor transport holds. We predict that the effective diffusion of the cargo driven by the multiple motors under load increases by an order of magnitude compared to that for the single motor. Finally, our simulations predict that the stochastic effects are responsible for a significant dispersion of velocities generated by the 'tug-of-war' of the multiple opposing motors.

  9. Robust transport by multiple motors with nonlinear force–velocity relations and stochastic load sharing

    PubMed Central

    Kunwar, Ambarish; Mogilner, Alexander

    2010-01-01

    Transport by processive molecular motors plays an important role in many cell biological phenomena. In many cases, motors work together to transport cargos in the cell, so it is important to understand the mechanics of the multiple motors. Based on earlier modeling efforts, here we study effects of nonlinear force–velocity relations and stochastic load sharing on multiple motor transport. We find that when two or three motors transport the cargo, then the nonlinear and stochastic effects compensate so that the mechanical properties of the transport are robust. Similarly, the transport is insensitive to compliance of the cargo-motor links. Furthermore, the rate of movement against moderate loads is not improved by increasing the small number of motors. When the motor number is greater than 4, correlations between the motors become negligible, and the earlier analytical mean-field theory of the multiple motor transport holds. We predict that the effective diffusion of the cargo driven by the multiple motors under load increases by an order of magnitude compared to that for the single motor. Finally, our simulations predict that the stochastic effects are responsible for a significant dispersion of velocities generated by the ‘tug-of-war’ of the multiple opposing motors. PMID:20147778

  10. Sex-linked dominant

    MedlinePlus

    Inheritance - sex-linked dominant; Genetics - sex-linked dominant; X-linked dominant; Y-linked dominant ... one of the sex chromosomes, which are the X and Y chromosomes. Dominant inheritance occurs when an ...

  11. Sex-linked recessive

    MedlinePlus

    Inheritance - sex-linked recessive; Genetics - sex-linked recessive; X-linked recessive ... X-linked recessive diseases usually occur in males. Males have only one X chromosome. A single recessive ...

  12. Sex-linked dominant

    MedlinePlus

    Inheritance - sex-linked dominant; Genetics - sex-linked dominant; X-linked dominant; Y-linked dominant ... type of chromosome that is affected (autosomal or sex chromosome). It also depends on whether the trait ...

  13. Rationales for improving motor function.

    PubMed

    Hummelsheim, H

    1999-12-01

    New findings in basic neuroscience, and the growing knowledge regarding neuroplasticity and motor learning have exerted influence and have provided stimuli for motor rehabilitation research. Repeated motor practice has been identified as crucial for motor recovery. Further novel and scientifically based therapeutic approaches have been developed: constraint-induced movement therapy, electromyogram-initiated neuromuscular stimulation, motor imagery and music therapy are all discussed in the present review. PMID:10676751

  14. Competing Neural Ensembles in Motor Cortex Gate Goal-Directed Motor Output.

    PubMed

    Zagha, Edward; Ge, Xinxin; McCormick, David A

    2015-11-01

    Unit recordings in behaving animals have revealed the transformation of sensory to motor representations in cortical neurons. However, we still lack basic insights into the mechanisms by which neurons interact to generate such transformations. Here, we study cortical circuits related to behavioral control in mice engaged in a sensory detection task. We recorded neural activity using extracellular and intracellular techniques and analyzed the task-related neural dynamics to reveal underlying circuit processes. Within motor cortex, we find two populations of neurons that have opposing spiking patterns in anticipation of movement. From correlation analyses and circuit modeling, we suggest that these dynamics reflect neural ensembles engaged in a competition. Furthermore, we demonstrate how this competitive circuit may convert a transient, sensory stimulus into a motor command. Together, these data reveal cellular and circuit processes underlying behavioral control and establish an essential framework for future studies linking cellular activity to behavior. PMID:26593093

  15. Obsessive-compulsive disorder: a "sensory-motor" problem?

    PubMed

    Russo, M; Naro, A; Mastroeni, C; Morgante, F; Terranova, C; Muscatello, M R; Zoccali, R; Calabrò, R S; Quartarone, A

    2014-05-01

    Obsessive-compulsive disorder (OCD) is a clinically heterogeneous condition. Although its pathophysiology is not completely understood, neurophysiologic and neuroimaging data have disclosed functional abnormalities in the networks linking frontal cortex, supplementary motor and premotor areas, striatum, globus pallidus, and thalamus (CSPT circuits). By means of transcranial magnetic stimulation (TMS) it is possible to test inhibitory and excitatory circuits within motor cortex. Previous studies on OCD patients under medication have demonstrated altered cortical inhibitory circuits as tested by TMS. On the other hand there is growing evidence suggesting an alteration of sensory-motor integration. Therefore, the aim of the present study was to evaluate sensory-motor integration (SAI and LAI), intracortical inhibition, and facilitation in drug-naïve OCD patients, using TMS. In our sample, we have demonstrated a significant SAI reduction in OCD patients when compared to a cohort of healthy individuals. SAI abnormalities may be related to a dysfunction of CSPT circuits which are involved in sensory-motor integration processes. Thus, it can be speculated that hypofunctioning of such system might impair the ability of OCD patients to suppress internally triggered intrusive and repetitive movements and thoughts. In conclusion, our data suggest that OCD may be considered as a sensory motor disorder where a dysfunction of sensory-motor integration may play an important role in the release of motor compulsions. PMID:24631627

  16. Seeing fearful body language rapidly freezes the observer's motor cortex.

    PubMed

    Borgomaneri, Sara; Vitale, Francesca; Gazzola, Valeria; Avenanti, Alessio

    2015-04-01

    Fearful body language is a salient signal alerting the observer to the presence of a potential threat in the surrounding environment. Although detecting potential threats may trigger an immediate reduction of motor output in animals (i.e., freezing behavior), it is unclear at what point in time similar reductions occur in the human motor cortex and whether they originate from excitatory or inhibitory processes. Using single-pulse and paired-pulse transcranial magnetic stimulation (TMS), here we tested the hypothesis that the observer's motor cortex implements extremely fast suppression of motor readiness when seeing emotional bodies - and fearful body expressions in particular. Participants observed pictures of body postures and categorized them as happy, fearful or neutral while receiving TMS over the right or left motor cortex at 100-125 msec after picture onset. In three different sessions, we assessed corticospinal excitability, short intracortical inhibition (SICI) and intracortical facilitation (ICF). Independently of the stimulated hemisphere and the time of the stimulation, watching fearful bodies suppressed ICF relative to happy and neutral body expressions. Moreover, happy expressions reduced ICF relative to neutral actions. No changes in corticospinal excitability or SICI were found during the task. These findings show extremely rapid bilateral modulation of the motor cortices when seeing emotional bodies, with stronger suppression of motor readiness when seeing fearful bodies. Our results provide neurophysiological support for the evolutionary notions that emotion perception is inherently linked to action systems and that fear-related cues induce an urgent mobilization of motor reactions. PMID:25835523

  17. A New Type of Motor: Pneumatic Step Motor

    PubMed Central

    Stoianovici, Dan; Patriciu, Alexandru; Petrisor, Doru; Mazilu, Dumitru; Kavoussi, Louis

    2011-01-01

    This paper presents a new type of pneumatic motor, a pneumatic step motor (PneuStep). Directional rotary motion of discrete displacement is achieved by sequentially pressurizing the three ports of the motor. Pulsed pressure waves are generated by a remote pneumatic distributor. The motor assembly includes a motor, gearhead, and incremental position encoder in a compact, central bore construction. A special electronic driver is used to control the new motor with electric stepper indexers and standard motion control cards. The motor accepts open-loop step operation as well as closed-loop control with position feedback from the enclosed sensor. A special control feature is implemented to adapt classic control algorithms to the new motor, and is experimentally validated. The speed performance of the motor degrades with the length of the pneumatic hoses between the distributor and motor. Experimental results are presented to reveal this behavior and set the expectation level. Nevertheless, the stepper achieves easily controllable precise motion unlike other pneumatic motors. The motor was designed to be compatible with magnetic resonance medical imaging equipment, for actuating an image-guided intervention robot, for medical applications. For this reason, the motors were entirely made of nonmagnetic and dielectric materials such as plastics, ceramics, and rubbers. Encoding was performed with fiber optics, so that the motors are electricity free, exclusively using pressure and light. PneuStep is readily applicable to other pneumatic or hydraulic precision-motion applications. PMID:21528106

  18. A New Type of Motor: Pneumatic Step Motor.

    PubMed

    Stoianovici, Dan; Patriciu, Alexandru; Petrisor, Doru; Mazilu, Dumitru; Kavoussi, Louis

    2007-02-01

    This paper presents a new type of pneumatic motor, a pneumatic step motor (PneuStep). Directional rotary motion of discrete displacement is achieved by sequentially pressurizing the three ports of the motor. Pulsed pressure waves are generated by a remote pneumatic distributor. The motor assembly includes a motor, gearhead, and incremental position encoder in a compact, central bore construction. A special electronic driver is used to control the new motor with electric stepper indexers and standard motion control cards. The motor accepts open-loop step operation as well as closed-loop control with position feedback from the enclosed sensor. A special control feature is implemented to adapt classic control algorithms to the new motor, and is experimentally validated. The speed performance of the motor degrades with the length of the pneumatic hoses between the distributor and motor. Experimental results are presented to reveal this behavior and set the expectation level. Nevertheless, the stepper achieves easily controllable precise motion unlike other pneumatic motors. The motor was designed to be compatible with magnetic resonance medical imaging equipment, for actuating an image-guided intervention robot, for medical applications. For this reason, the motors were entirely made of nonmagnetic and dielectric materials such as plastics, ceramics, and rubbers. Encoding was performed with fiber optics, so that the motors are electricity free, exclusively using pressure and light. PneuStep is readily applicable to other pneumatic or hydraulic precision-motion applications. PMID:21528106

  19. Contribution of hand motor circuits to counting.

    PubMed

    Andres, Michael; Seron, Xavier; Olivier, Etienne

    2007-04-01

    The finding that number processing activates a cortical network partly overlapping that recruited for hand movements has renewed interest in the relationship between number and finger representations. Further evidence about a possible link between fingers and numbers comes from developmental studies showing that finger movements play a crucial role in learning counting. However, increased activity in hand motor circuits during counting may unveil unspecific processes, such as shifting attention, reciting number names, or matching items with a number name. To address this issue, we used transcranial magnetic stimulation to measure changes in corticospinal (CS) excitability during a counting task performed silently and using either numbers or letters of the alphabet to enumerate items. We found an increased CS excitability of hand muscles during the counting task, irrespective of the use of numbers or letters, whereas it was unchanged in arm and foot muscles. Control tasks allowed us to rule out a possible influence of attention allocation or covert speech on CS excitability increase of hand muscles during counting. The present results support a specific involvement of hand motor circuits in counting because no CS changes were found in arm and foot muscles during the same task. However, the contribution of hand motor areas is not exclusively related to number processing because an increase in CS excitability was also found when letters were used to enumerate items. This finding suggests that hand motor circuits are involved whenever items have to be put in correspondence with the elements of any ordered series. PMID:17381248

  20. Sensory-motor integration in focal dystonia.

    PubMed

    Avanzino, Laura; Tinazzi, Michele; Ionta, Silvio; Fiorio, Mirta

    2015-12-01

    Traditional definitions of focal dystonia point to its motor component, mainly affecting planning and execution of voluntary movements. However, focal dystonia is tightly linked also to sensory dysfunction. Accurate motor control requires an optimal processing of afferent inputs from different sensory systems, in particular visual and somatosensory (e.g., touch and proprioception). Several experimental studies indicate that sensory-motor integration - the process through which sensory information is used to plan, execute, and monitor movements - is impaired in focal dystonia. The neural degenerations associated with these alterations affect not only the basal ganglia-thalamic-frontal cortex loop, but also the parietal cortex and cerebellum. The present review outlines the experimental studies describing impaired sensory-motor integration in focal dystonia, establishes their relationship with changes in specific neural mechanisms, and provides new insight towards the implementation of novel intervention protocols. Based on the reviewed state-of-the-art evidence, the theoretical framework summarized in the present article will not only result in a better understanding of the pathophysiology of dystonia, but it will also lead to the development of new rehabilitation strategies. PMID:26164472

  1. Genetic Deficiency of GABA Differentially Regulates Respiratory and Non-Respiratory Motor Neuron Development

    PubMed Central

    Yanagawa, Yuchio; Obata, Kunihiko; Bellingham, Mark C.; Noakes, Peter G.

    2013-01-01

    Central nervous system GABAergic and glycinergic synaptic activity switches from postsynaptic excitation to inhibition during the stage when motor neuron numbers are being reduced, and when synaptic connections are being established onto and by motor neurons. In mice this occurs between embryonic (E) day 13 and birth (postnatal day 0). Our previous work on mice lacking glycinergic transmission suggested that altered motor neuron activity levels correspondingly regulated motor neuron survival and muscle innervation for all respiratory and non respiratory motor neuron pools, during this period of development [1]. To determine if GABAergic transmission plays a similar role, we quantified motor neuron number and the extent of muscle innervation in four distinct regions of the brain stem and spinal cord; hypoglossal, phrenic, brachial and lumbar motor pools, in mice lacking the enzyme GAD67. These mice display a 90% drop in CNS GABA levels ( [2]; this study). For respiratory-based motor neurons (hypoglossal and phrenic motor pools), we have observed significant drops in motor neuron number (17% decline for hypoglossal and 23% decline for phrenic) and muscle innervations (55% decrease). By contrast for non-respiratory motor neurons of the brachial lateral motor column, we have observed an increase in motor neuron number (43% increase) and muscle innervations (99% increase); however for more caudally located motor neurons within the lumbar lateral motor column, we observed no change in either neuron number or muscle innervation. These results show in mice lacking physiological levels of GABA, there are distinct regional changes in motor neuron number and muscle innervation, which appear to be linked to their physiological function and to their rostral-caudal position within the developing spinal cord. Our results also suggest that for more caudal (lumbar) regions of the spinal cord, the effect of GABA is less influential on motor neuron development compared to that of

  2. Motor considerations for turbomachinery

    SciTech Connect

    Halfpap, R.F.; Brotherhood, R. )

    1995-02-01

    Customers who use large rotating equipment realize motors can be subjected to hostile environmental conditions, nonstandard voltage levels and a variety of load requirements. The motor specifications they write reflect this change and have become far more detailed. Too often in the past, when large projects were being organized and highly technical equipment purchased, induction motors were thought of as standard pieces of equipment not requiring much in the way of specialized design. High-speed compressor applications are good examples of the need for specific compressor torque characteristics and starting requirements to allow for proper motor design. Not only different compressor designs, but adjustments in compressor valves and changes in gas process conditions, can produce a diversity of speed-torque curves. Therefore, it is not practical for a motor designer to be told to assume a standard compressor load torque during acceleration. An example of compressor speed-torque curves illustrates this point. The paper also presents the example of centrifugal pumps to further illustrate the need for properly matching driver torque and power requirements.

  3. Magnetostrictive direct drive motor

    NASA Technical Reports Server (NTRS)

    Naik, Dipak; Dehoff, P. H.

    1991-01-01

    Highly magnetostrictive materials such as Tb.3Dy.7Fe2, commercially known as TERFENOL-D, have been used to date in a variety of devices such as high power actuators and linear motors. The larger magnetostriction available in twinned single crystal TERFENOL-D, approx. 2000 ppm at moderate magnetic field strengths, makes possible a new generation of magnetomechanical devices. NASA researchers are studying the potential of this material as the basis for a direct microstepping rotary motor with torque densities on the order of industrial hydraulics and five times greater than that of the most efficient, high power electric motors. Such a motor would be a micro-radian stepper, capable of precision movements and self-braking in the power-off state. Innovative mechanical engineering techniques are juxtaposed on proper magnetic circuit design to reduce losses in structural flexures, inertias, thermal expansions, eddy currents, and magneto-mechanical coupling, thus optimizing motor performance and efficiency. Mathematical models are presented, including magnetic, structural, and both linear and nonlinear dynamic calculations and simulations. In addition, test results on prototypes are presented.

  4. Damage to Fronto-Parietal Networks Impairs Motor Imagery Ability after Stroke: A Voxel-Based Lesion Symptom Mapping Study

    PubMed Central

    Oostra, Kristine M.; Van Bladel, Anke; Vanhoonacker, Ann C. L.; Vingerhoets, Guy

    2016-01-01

    Background: Mental practice with motor imagery has been shown to promote motor skill acquisition in healthy subjects and patients. Although lesions of the common motor imagery and motor execution neural network are expected to impair motor imagery ability, functional equivalence appears to be at least partially preserved in stroke patients. Aim: To identify brain regions that are mandatory for preserved motor imagery ability after stroke. Method: Thirty-seven patients with hemiplegia after a first time stroke participated. Motor imagery ability was measured using a Motor Imagery questionnaire and temporal congruence test. A voxelwise lesion symptom mapping approach was used to identify neural correlates of motor imagery in this cohort within the first year post-stroke. Results: Poor motor imagery vividness was associated with lesions in the left putamen, left ventral premotor cortex and long association fibers linking parieto-occipital regions with the dorsolateral premotor and prefrontal areas. Poor temporal congruence was otherwise linked to lesions in the more rostrally located white matter of the superior corona radiata. Conclusion: This voxel-based lesion symptom mapping study confirms the association between white matter tract lesions and impaired motor imagery ability, thus emphasizing the importance of an intact fronto-parietal network for motor imagery. Our results further highlight the crucial role of the basal ganglia and premotor cortex when performing motor imagery tasks. PMID:26869894

  5. Micromachine Wedge Stepping Motor

    SciTech Connect

    Allen, J.J.; Schriner, H.K.

    1998-11-04

    A wedge stepping motor, which will index a mechanism, has been designed and fabricated in the surface rnicromachine SUMMiT process. This device has demonstrated the ability to index one gear tooth at a time with speeds up to 205 teeth/see. The wedge stepper motor has the following features, whi:h will be useful in a number of applications. o The ability to precisely position mechanical components. . Simple pulse signals can be used for operation. o Only 2 drive signals are requixed for operation. o Torque and precision capabilities increase with device size . The device to be indexed is restrained at all times by the wedge shaped tooth that is used for actuation. This paper will discuss the theory of operation and desi=m of the wedge stepping motor. The fabrication and testing of I he device will also be presented.

  6. Rocket motor aeroacoustics

    NASA Astrophysics Data System (ADS)

    Hegde, U. G.; Strahle, W. C.

    1983-10-01

    Vibration problems in solid propellant rocket motors are investigated. A class of interior flows modelled to simulate flow conditions inside rocket motor cavities is considered. Turbulence generated pressure fluctuations are shown to consist of two components - acoustic and hydrodynamics. The Bernoulli enthalpy theory of aeroacoustics is employed to extract acoustic pressure spectra from experimentally obtained turbulence data and acoustic impedance values at flow boundaries. The effects of turbulence intensities, sidewall acoustic impedance, axial mass blowing distribution, length to diameter ratio of the cavity and different mass flux on the acoustic pressure level are investigated. Typical pressure levels, under rocket motor conditions, are calculated using the A/B model of propellant response. Estimates of the hydrodynamic component of the pressure fluctuation are provided for the case of fully developed turbulent pipe flow terminated by a choked nozzle.

  7. Bent shaft motor

    DOEpatents

    Benavides, G.L.

    1998-05-05

    A nonelectromagnetic motor comprising a base, a bent shaft which is rotatable relative to the base wherein the bent shaft comprises a straight portion aligned with a main axis and an offset portion that is offset with respect to the main axis; and a drive means for driving the offset portion of the bent shaft along a generally circular path in a plane perpendicular to the main axis to rotate the bent shaft. The bent shaft and drive means for driving the bent shaft can be selected from piezoelectric, magnetostrictive, rheological and shape memory alloys. The drive means of the nonelectromagnetic motor can additionally comprise a shell which shell surrounds and houses the bent shaft and precesses or gyrates which in turn causes the bent drive shaft to rotate. The nonelectromagnetic motor does not rely on friction for the application of torque upon a rotor. 11 figs.

  8. Magnetostrictive direct drive motors

    NASA Technical Reports Server (NTRS)

    Naik, Dipak; Dehoff, P. H.

    1990-01-01

    Developing magnetostrictive direct drive research motors to power robot joints is discussed. These type motors are expected to produce extraordinary torque density, to be able to perform microradian incremental steps and to be self-braking and safe with the power off. Several types of motor designs have been attempted using magnetostrictive materials. One of the candidate approaches (the magnetostrictive roller drive) is described. The method in which the design will function is described as is the reason why this approach is inherently superior to the other approaches. Following this, the design will be modelled and its expected performance predicted. This particular candidate design is currently undergoing detailed engineering with prototype construction and testing scheduled for mid 1991.

  9. Bent shaft motor

    DOEpatents

    Benavides, Gilbert L.

    1998-01-01

    A nonelectromagnetic motor comprising a base, a bent shaft which is rotable relative to the base wherein the bent shaft comprises a straight portion aligned with a main axis and an offset portion that is offset with respect to the main axis; and a drive means for driving the offset portion of the bent shaft along a generally circular path in a plane perpendicular to the main axis to rotate the bent shaft. The bent shaft and drive means for driving the bent shaft can be selected from piezoelectric, magnetostrictive, rheological and shape memory alloys. The drive means of the nonelectromagnetic motor can additionally comprise a shell which shell surrounds and houses the bent shaft and precesses or gyrates which in turn causes the bent drive shaft to rotate. The nonelectromagnetic motor does not rely on friction for the application of torque upon a rotor.

  10. Effects of Vestibular Stimulation on Motor Development and Stereotyped Behavior of Developmentally Delayed Children.

    ERIC Educational Resources Information Center

    MacLean, William E., Jr.; Baumeister, Alfred A.

    1982-01-01

    Four developmentally delayed babies were given semicircular canal stimulation in an effort to facilitate their motor and reflex development. All of the children showed motor and/or reflex changes that were attributable to the vestibular stimulation. In addition, some evidence was obtained linking changes in stereotypic responding to the vestibular…

  11. 48 CFR 970.5223-5 - DOE motor vehicle fleet fuel efficiency.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... and Contract Clauses for Management and Operating Contracts 970.5223-5 DOE motor vehicle fleet fuel efficiency. Link to an amendment published at 75 FR 57695, Sept. 22, 2010. As prescribed in 48 CFR 970.2307-2... 48 Federal Acquisition Regulations System 5 2010-10-01 2010-10-01 false DOE motor vehicle...

  12. Effects of Dispositional Mindfulness on the Self-Controlled Learning of a Novel Motor Task

    ERIC Educational Resources Information Center

    Kee, Ying Hwa; Liu, Yeou-Teh

    2011-01-01

    Current literature suggests that mindful learning is beneficial to learning but its links with motor learning is seldom examined. In the present study, we examine the effects of learners' mindfulness disposition on the self-controlled learning of a novel motor task. Thirty-two participants undertook five practice sessions, in addition to a pre-,…

  13. An Examination of the Relationship between Motor Coordination and Executive Functions in Adolescents

    ERIC Educational Resources Information Center

    Rigoli, Daniela; Piek, Jan P.; Kane, Robert; Oosterlaan, Jaap

    2012-01-01

    Aim: Research suggests important links between motor coordination and executive functions. The current study examined whether motor coordination predicts working memory, inhibition, and switching performance, extending previous research by accounting for attention-deficit-hyperactivity disorder (ADHD) symptomatology and other confounding factors,…

  14. The functional alterations associated with motor imagery training: a comparison between motor execution and motor imagery of sequential finger tapping

    NASA Astrophysics Data System (ADS)

    Zhang, Hang; Yao, Li; Long, Zhiying

    2011-03-01

    Motor imagery training, as an effective strategy, has been more and more applied to mental disorders rehabilitation and motor skill learning. Studies on the neural mechanism underlying motor imagery have suggested that such effectiveness may be related to the functional congruence between motor execution and motor imagery. However, as compared to the studies on motor imagery, the studies on motor imagery training are much fewer. The functional alterations associated with motor imagery training and the effectiveness of motor imagery training on motor performance improvement still needs further investigation. Using fMRI, we employed a sequential finger tapping paradigm to explore the functional alterations associated with motor imagery training in both motor execution and motor imagery task. We hypothesized through 14 consecutive days motor imagery training, the motor performance could be improved and the functional congruence between motor execution and motor imagery would be sustained form pre-training phase to post-training phase. Our results confirmed the effectiveness of motor imagery training in improving motor performance and demonstrated in both pre and post-training phases, motor imagery and motor execution consistently sustained the congruence in functional neuroanatomy, including SMA (supplementary motor cortex), PMA (premotor area); M1( primary motor cortex) and cerebellum. Moreover, for both execution and imagery tasks, a similar functional alteration was observed in fusiform through motor imagery training. These findings provided an insight into the effectiveness of motor imagery training and suggested its potential therapeutic value in motor rehabilitation.

  15. ac bidirectional motor controller

    NASA Technical Reports Server (NTRS)

    Schreiner, K.

    1988-01-01

    Test data are presented and the design of a high-efficiency motor/generator controller at NASA-Lewis for use with the Space Station power system testbed is described. The bidirectional motor driver is a 20 kHz to variable frequency three-phase ac converter that operates from the high-frequency ac bus being designed for the Space Station. A zero-voltage-switching pulse-density-modulation technique is used in the converter to shape the low-frequency output waveform.

  16. Motor current signature analysis method for diagnosing motor operated devices

    DOEpatents

    Haynes, Howard D.; Eissenberg, David M.

    1990-01-01

    A motor current noise signature analysis method and apparatus for remotely monitoring the operating characteristics of an electric motor-operated device such as a motor-operated valve. Frequency domain signal analysis techniques are applied to a conditioned motor current signal to distinctly identify various operating parameters of the motor driven device from the motor current signature. The signature may be recorded and compared with subsequent signatures to detect operating abnormalities and degradation of the device. This diagnostic method does not require special equipment to be installed on the motor-operated device, and the current sensing may be performed at remote control locations, e.g., where the motor-operated devices are used in accessible or hostile environments.

  17. Disentangling fine motor skills' relations to academic achievement: the relative contributions of visual-spatial integration and visual-motor coordination.

    PubMed

    Carlson, Abby G; Rowe, Ellen; Curby, Timothy W

    2013-01-01

    Recent research has established a connection between children's fine motor skills and their academic performance. Previous research has focused on fine motor skills measured prior to elementary school, while the present sample included children ages 5-18 years old, making it possible to examine whether this link remains relevant throughout childhood and adolescence. Furthermore, the majority of research linking fine motor skills and academic achievement has not determined which specific components of fine motor skill are driving this relation. The few studies that have looked at associations of separate fine motor tasks with achievement suggest that copying tasks that tap visual-spatial integration skills are most closely related to achievement. The present study examined two separate elements of fine motor skills--visual-motor coordination and visual-spatial integration--and their associations with various measures of academic achievement. Visual-motor coordination was measured using tracing tasks, while visual-spatial integration was measured using copy-a-figure tasks. After controlling for gender, socioeconomic status, IQ, and visual-motor coordination, and visual-spatial integration explained significant variance in children's math and written expression achievement. Knowing that visual-spatial integration skills are associated with these two achievement domains suggests potential avenues for targeted math and writing interventions for children of all ages. PMID:24303571

  18. 46 CFR 169.684 - Overcurrent protection for motors and motor branch circuits.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 46 Shipping 7 2012-10-01 2012-10-01 false Overcurrent protection for motors and motor branch... motors and motor branch circuits. (a) Except as provided in paragraph (d) of this section, each motor... motor that is responsive to motor current or to both motor current and temperature may be used. (b)...

  19. 46 CFR 169.684 - Overcurrent protection for motors and motor branch circuits.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 46 Shipping 7 2011-10-01 2011-10-01 false Overcurrent protection for motors and motor branch... motors and motor branch circuits. (a) Except as provided in paragraph (d) of this section, each motor... motor that is responsive to motor current or to both motor current and temperature may be used. (b)...

  20. 46 CFR 169.684 - Overcurrent protection for motors and motor branch circuits.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 46 Shipping 7 2010-10-01 2010-10-01 false Overcurrent protection for motors and motor branch... motors and motor branch circuits. (a) Except as provided in paragraph (d) of this section, each motor... motor that is responsive to motor current or to both motor current and temperature may be used. (b)...

  1. 46 CFR 169.684 - Overcurrent protection for motors and motor branch circuits.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 46 Shipping 7 2014-10-01 2014-10-01 false Overcurrent protection for motors and motor branch... motors and motor branch circuits. (a) Except as provided in paragraph (d) of this section, each motor... motor that is responsive to motor current or to both motor current and temperature may be used. (b)...

  2. 46 CFR 169.684 - Overcurrent protection for motors and motor branch circuits.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 46 Shipping 7 2013-10-01 2013-10-01 false Overcurrent protection for motors and motor branch... motors and motor branch circuits. (a) Except as provided in paragraph (d) of this section, each motor... motor that is responsive to motor current or to both motor current and temperature may be used. (b)...

  3. Multiscale Polar Theory of Microtubule and Motor-Protein Assemblies

    PubMed Central

    Gao, Tong; Blackwell, Robert; Glaser, Matthew A.; Betterton, M. D.; Shelley, Michael J.

    2015-01-01

    Microtubules and motor proteins are building blocks of self-organized subcellular biological structures such as the mitotic spindle and the centrosomal microtubule array. These same ingredients can form new “bioactive” liquid-crystalline fluids that are intrinsically out of equilibrium and which display complex flows and defect dynamics. It is not yet well understood how microscopic activity, which involves polarity-dependent interactions between motor proteins and microtubules, yields such larger-scale dynamical structures. In our multiscale theory, Brownian dynamics simulations of polar microtubule ensembles driven by cross-linking motors allow us to study microscopic organization and stresses. Polarity sorting and cross-link relaxation emerge as two polar-specific sources of active destabilizing stress. On larger length scales, our continuum Doi-Onsager theory captures the hydrodynamic flows generated by polarity-dependent active stresses. The results connect local polar structure to flow structures and defect dynamics. PMID:25679909

  4. Self-organization of dynein motors generates meiotic nuclear oscillations.

    PubMed

    Vogel, Sven K; Pavin, Nenad; Maghelli, Nicola; Jülicher, Frank; Tolić-Nørrelykke, Iva M

    2009-04-21

    Meiotic nuclear oscillations in the fission yeast Schizosaccharomyces pombe are crucial for proper chromosome pairing and recombination. We report a mechanism of these oscillations on the basis of collective behavior of dynein motors linking the cell cortex and dynamic microtubules that extend from the spindle pole body in opposite directions. By combining quantitative live cell imaging and laser ablation with a theoretical description, we show that dynein dynamically redistributes in the cell in response to load forces, resulting in more dynein attached to the leading than to the trailing microtubules. The redistribution of motors introduces an asymmetry of motor forces pulling in opposite directions, leading to the generation of oscillations. Our work provides the first direct in vivo observation of self-organized dynamic dynein distributions, which, owing to the intrinsic motor properties, generate regular large-scale movements in the cell. PMID:19385717

  5. Method for assessing motor insulation on operating motors

    DOEpatents

    Kueck, J.D.; Otaduy, P.J.

    1997-03-18

    A method for monitoring the condition of electrical-motor-driven devices is disclosed. The method is achieved by monitoring electrical variables associated with the functioning of an operating motor, applying these electrical variables to a three phase equivalent circuit and determining non-symmetrical faults in the operating motor based upon symmetrical components analysis techniques. 15 figs.

  6. Method for assessing motor insulation on operating motors

    DOEpatents

    Kueck, John D.; Otaduy, Pedro J.

    1997-01-01

    A method for monitoring the condition of electrical-motor-driven devices. The method is achieved by monitoring electrical variables associated with the functioning of an operating motor, applying these electrical variables to a three phase equivalent circuit and determining non-symmetrical faults in the operating motor based upon symmetrical components analysis techniques.

  7. Magnetically Coupled Adjustable Speed Motor Drives - Motor Tip Sheet #13

    SciTech Connect

    2008-07-01

    Alternating current electric motors rotate at a nearly constant speed that is determined by motor design and line frequency. Energy savings of 50% or more may be available when fixed speed systems are modified to allow the motor speed to match variable load requirements of a centrifugal fan or pump.

  8. A Sensorless Starting Method for Self-Controlled Synchronous Motors

    NASA Astrophysics Data System (ADS)

    Hasegawa, Chihiro; Nishikata, Shoji

    A self-controlled synchronous motor is being used as a variable speed motor in industries to date, and nowadays it is also used for propelling a ship. In this type of motor, the information of rotor position is needed to achieve stable operations. A simple sensorless starting method for this motor is studied in this paper. An initial rotor position detecting method without any position sensor is first discussed. It is shown that the position can be detected easily by observing the electromotive forces induced in the armature windings due to the change in the field current. Then, a new starting method for the motor is proposed on the basis of the DC link current chopping during the starting period. It is clarified that based on the proposed method the starting of the motor can be realized independently of the load conditions, supporting the usefulness of the proposed method. Finally, the effects of various parameters in the system on the responses of dc input current and motor speed during starting up are discussed.

  9. Electric motor model repair specifications

    SciTech Connect

    1995-08-01

    These model repair specifications list the minimum requirements for repair and overhaul of polyphase AC squireel cage induction motors. All power ranges, voltages, and speeds of squirrel cage motors are covered.

  10. The St. Louis Motor

    ERIC Educational Resources Information Center

    Greenslade, Thomas B., Jr.

    2011-01-01

    The St. Louis Motor, invented in 1909, is unique among physics apparatus for being named for a geographical place rather than a physicist. The sturdy little device (Fig. 1) has never been out of production. Any older school or physics department that has not done a catastrophic housecleaning in the last 20 years will certainly have a small flock…

  11. Human Spinal Motor Control.

    PubMed

    Nielsen, Jens Bo

    2016-07-01

    Human studies in the past three decades have provided us with an emerging understanding of how cortical and spinal networks collaborate to ensure the vast repertoire of human behaviors. Humans have direct cortical connections to spinal motoneurons, which bypass spinal interneurons and exert a direct (willful) muscle control with the aid of a context-dependent integration of somatosensory and visual information at cortical level. However, spinal networks also play an important role. Sensory feedback through spinal circuitries is integrated with central motor commands and contributes importantly to the muscle activity underlying voluntary movements. Regulation of spinal interneurons is used to switch between motor states such as locomotion (reciprocal innervation) and stance (coactivation pattern). Cortical regulation of presynaptic inhibition of sensory afferents may focus the central motor command by opening or closing sensory feedback pathways. In the future, human studies of spinal motor control, in close collaboration with animal studies on the molecular biology of the spinal cord, will continue to document the neural basis for human behavior. PMID:27023730

  12. Perceptual-Motor Dysfunction.

    ERIC Educational Resources Information Center

    Pyfer, Jean L.

    Discussed are theoretical and treatment aspects of perceptual motor dysfunction and rehabilitation in 4- to 12-year-old academically failing children involved in a 3-year investigation at the University of Kansas. The program is said to stress increasing the amount of stimulation received by sensory receptors of the vestibular, reflex, and haptic…

  13. Thiokol Solid Rocket Motors

    NASA Technical Reports Server (NTRS)

    Graves, S. R.

    2000-01-01

    This paper presents viewgraphs on thiokol solid rocket motors. The topics include: 1) Communications; 2) Military and government intelligence; 3) Positioning satellites; 4) Remote sensing; 5) Space burial; 6) Science; 7) Space manufacturing; 8) Advertising; 9) Space rescue space debris management; 10) Space tourism; 11) Space settlements; 12) Hazardous waste disposal; 13) Extraterrestrial resources; 14) Fast package delivery; and 15) Space utilities.

  14. Reciprocating Linear Electric Motor

    NASA Technical Reports Server (NTRS)

    Goldowsky, M. P.

    1984-01-01

    Features include structural simplicity and good force/displacement characteristics. Reciprocating motor has simple, rugged construction, relatively low reciprocating weight, improved power delivery, and improved force control. Wear reduced by use of magnetic bearings. Intended to provide drivers for long-lived Stirling-cycle cryogenic refrigerators, concept has less exotic applications, such as fuel pumps.

  15. Molecular motors: Dynein's gearbox.

    PubMed

    Cross, R A

    2004-05-01

    A new optical trapping study shows that the stepsize of cytoplasmic dynein varies according to the applied force, suggesting that this motor can change gear. Complementary biochemical kinetic work on yeast dynein mutants hints at the allosteric mechanisms involved. PMID:15120091

  16. Solid rocket motors

    NASA Technical Reports Server (NTRS)

    Carpenter, Ronn L.

    1993-01-01

    Structural requirements, materials and, especially, processing are critical issues that will pace the introduction of new types of solid rocket motors. Designers must recognize and understand the drivers associated with each of the following considerations: (1) cost; (2) energy density; (3) long term storage with use on demand; (4) reliability; (5) safety of processing and handling; (6) operability; and (7) environmental acceptance.

  17. Changes in visual and sensory-motor resting-state functional connectivity support motor learning by observing.

    PubMed

    McGregor, Heather R; Gribble, Paul L

    2015-07-01

    Motor learning occurs not only through direct first-hand experience but also through observation (Mattar AA, Gribble PL. Neuron 46: 153-160, 2005). When observing the actions of others, we activate many of the same brain regions involved in performing those actions ourselves (Malfait N, Valyear KF, Culham JC, Anton JL, Brown LE, Gribble PL. J Cogn Neurosci 22: 1493-1503, 2010). Links between neural systems for vision and action have been reported in neurophysiological (Strafella AP, Paus T. Neuroreport 11: 2289-2292, 2000; Watkins KE, Strafella AP, Paus T. Neuropsychologia 41: 989-994, 2003), brain imaging (Buccino G, Binkofski F, Fink GR, Fadiga L, Fogassi L, Gallese V, Seitz RJ, Zilles K, Rizzolatti G, Freund HJ. Eur J Neurosci 13: 400-404, 2001; Iacoboni M, Woods RP, Brass M, Bekkering H, Mazziotta JC, Rizzolatti G. Science 286: 2526-2528, 1999), and eye tracking (Flanagan JR, Johansson RS. Nature 424: 769-771, 2003) studies. Here we used a force field learning paradigm coupled with resting-state fMRI to investigate the brain areas involved in motor learning by observing. We examined changes in resting-state functional connectivity (FC) after an observational learning task and found a network consisting of V5/MT, cerebellum, and primary motor and somatosensory cortices in which changes in FC were correlated with the amount of motor learning achieved through observation, as assessed behaviorally after resting-state fMRI scans. The observed FC changes in this network are not due to visual attention to motion or observation of movement errors but rather are specifically linked to motor learning. These results support the idea that brain networks linking action observation and motor control also facilitate motor learning. PMID:25995349

  18. Motor Education: Educational Development Programs.

    ERIC Educational Resources Information Center

    Tansley, A. E.

    This booklet presents educational programs and activities focusing on motor skills for 5- to 9-year-old children and older children with learning problems. The premise of the activities is that the acquisition of motor skills is essential to basic learning. The role of language as a mediator and controller of motor development is emphasized. The…

  19. Experiments with a DC Motor

    ERIC Educational Resources Information Center

    Kraftmakher, Yaakov

    2010-01-01

    Experiments with an electric motor provide good opportunity to demonstrate some basic laws of electricity and magnetism. The aim of the experiments with a low-power dc motor is to show how the motor approaches its steady rotation and how its torque, mechanical power and efficiency depend on the rotation velocity. The tight relationship between the…

  20. Multiple stage miniature stepping motor

    DOEpatents

    Niven, William A.; Shikany, S. David; Shira, Michael L.

    1981-01-01

    A stepping motor comprising a plurality of stages which may be selectively activated to effect stepping movement of the motor, and which are mounted along a common rotor shaft to achieve considerable reduction in motor size and minimum diameter, whereby sequential activation of the stages results in successive rotor steps with direction being determined by the particular activating sequence followed.

  1. Motor Vehicle Theft. Special Report.

    ERIC Educational Resources Information Center

    Harlow, Caroline Wolf

    Thirteen years of data from the National Crime Survey were analyzed to examine the characteristics of motor vehicle theft, to identify trends during the past 13 years, and to determine who are most likely to be victims of motor vehicle theft. All motor vehicle thefts reported to the National Crime Survey from 1973 through 1985 were examined.…

  2. Speed control for synchronous motors

    NASA Technical Reports Server (NTRS)

    Packard, H.; Schott, J.

    1981-01-01

    Feedback circuit controls fluctuations in speed of synchronous ac motor. Voltage proportional to phase angle is developed by phase detector, rectified, amplified, compared to threshold, and reapplied positively or negatively to motor excitation circuit. Speed control reduces wow and flutter of audio turntables and tape recorders, and enhances hunting in gyroscope motors.

  3. Brief Report: Children with ADHD without Co-Morbid Autism Do Not Have Impaired Motor Proficiency on the Movement Assessment Battery for Children

    ERIC Educational Resources Information Center

    Papadopoulos, Nicole; Rinehart, Nicole; Bradshaw, John L.; McGinley, Jennifer L.

    2013-01-01

    Motor proficiency was investigated in a sample of children with Attention Deficit Hyperactivity Disorder-Combined type (ADHD-CT) without autism. Accounting for the influence of co-morbid autistic symptoms in ADHD motor studies is vital given that motor impairment has been linked to social-communication symptoms in children who have co-morbid ADHD…

  4. Motor sequence learning and motor adaptation in primary cervical dystonia.

    PubMed

    Katschnig-Winter, Petra; Schwingenschuh, Petra; Davare, Marco; Sadnicka, Anna; Schmidt, Reinhold; Rothwell, John C; Bhatia, Kailash P; Edwards, Mark J

    2014-06-01

    Motor sequence learning and motor adaptation rely on overlapping circuits predominantly involving the basal ganglia and cerebellum. Given the importance of these brain regions to the pathophysiology of primary dystonia, and the previous finding of abnormal motor sequence learning in DYT1 gene carriers, we explored motor sequence learning and motor adaptation in patients with primary cervical dystonia. We recruited 12 patients with cervical dystonia and 11 healthy controls matched for age. Subjects used a joystick to move a cursor from a central starting point to radial targets as fast and accurately as possible. Using this device, we recorded baseline motor performance, motor sequence learning and a visuomotor adaptation task. Patients with cervical dystonia had a significantly higher peak velocity than controls. Baseline performance with random target presentation was otherwise normal. Patients and controls had similar levels of motor sequence learning and motor adaptation. Our patients had significantly higher peak velocity compared to controls, with similar movement times, implying a different performance strategy. The preservation of motor sequence learning in cervical dystonia patients contrasts with the previously observed deficit seen in patients with DYT1 gene mutations, supporting the hypothesis of differing pathophysiology in different forms of primary dystonia. Normal motor adaptation is an interesting finding. With our paradigm we did not find evidence that the previously documented cerebellar abnormalities in cervical dystonia have a behavioral correlate, and thus could be compensatory or reflect "contamination" rather than being directly pathological. PMID:24411324

  5. Motor Controller System For Large Dynamic Range of Motor Operation

    NASA Technical Reports Server (NTRS)

    Howard, David E. (Inventor); Alhorn, Dean C. (Inventor); Smith, Dennis A. (Inventor); Dutton, Kenneth R. (Inventor); Paulson, Mitchell Scott (Inventor)

    2006-01-01

    A motor controller system uses a rotary sensor with a plurality of signal conditioning units, coupled to the rotary sensor. Each of these units, which is associated with a particular range of motor output shaft rotation rates, generate a feedback signal indicative of the position of the motor s output shaft. A controller (i) converts a selected motor output shaft rotation rate to a corresponding incremental amount of rotational movement for a selected fixed time period, (ii) selects, at periodic completions of the selected fixed time period, the feedback signal from one of the signal conditioning units for which the particular range of motor output shaft rotation rates associated therewith encompasses the selected motor output shaft rotation rate, and (iii) generates a motor drive signal based on a difference between the incremental amount of rotational movement and the feedback signal from the selected one of the signal conditioning Units.

  6. Variation in motor output and motor performance in a centrally generated motor pattern

    PubMed Central

    Norris, Brian J.; Doloc-Mihu, Anca; Calabrese, Ronald L.

    2014-01-01

    Central pattern generators (CPGs) produce motor patterns that ultimately drive motor outputs. We studied how functional motor performance is achieved, specifically, whether the variation seen in motor patterns is reflected in motor performance and whether fictive motor patterns differ from those in vivo. We used the leech heartbeat system in which a bilaterally symmetrical CPG coordinates segmental heart motor neurons and two segmented heart tubes into two mutually exclusive coordination modes: rear-to-front peristaltic on one side and nearly synchronous on the other, with regular side-to-side switches. We assessed individual variability of the motor pattern and the beat pattern in vivo. To quantify the beat pattern we imaged intact adults. To quantify the phase relations between motor neurons and heart constrictions we recorded extracellularly from two heart motor neurons and movement from the corresponding heart segments in minimally dissected leeches. Variation in the motor pattern was reflected in motor performance only in the peristaltic mode, where larger intersegmental phase differences in the motor neurons resulted in larger phase differences between heart constrictions. Fictive motor patterns differed from those in vivo only in the synchronous mode, where intersegmental phase differences in vivo had a larger front-to-rear bias and were more constrained. Additionally, load-influenced constriction timing might explain the amplification of the phase differences between heart segments in the peristaltic mode and the higher variability in motor output due to body shape assumed in this soft-bodied animal. The motor pattern determines the beat pattern, peristaltic or synchronous, but heart mechanics influence the phase relations achieved. PMID:24717348

  7. Motor technology for mining applications advances

    SciTech Connect

    Fiscor, S.

    2009-08-15

    AC motors are steadily replacing DC motors in mining and mineral processing equipment, requiring less maintenance. The permanent magnet rotor, or the synchronous motor, has enabled Blador to introduce a line of cooling tower motors. Synchronous motors are soon likely to take over from the induction motor. 1 photo.

  8. The relation between measures of cognitive and motor functioning in 5- to 6-year-old children.

    PubMed

    Stöckel, Tino; Hughes, Charmayne M L

    2016-07-01

    Specific relations between executive functions (working memory capacity, planning and problem-solving, inhibitory control) and motor skill performance (anticipatory motor planning, manual dexterity) were examined in 5- to 6-year-old children (N = 40). Results showed that the two motor skill components were not correlated. Additionally, it was found that response planning performance was a significant predictor of anticipatory motor planning performance, whereas inhibitory control and working memory capacity measures were significant predictors of manual dexterity scores. Taken together, these results suggest that cognitive and motor skills are linked, but that manual dexterity and anticipatory motor planning involve different specialized skills. The current study provides support for specific relations between cognitive and motor performance, which has implications for early childhood cognitive-motor training and intervention programs. PMID:25820330

  9. Dynamic Re-wiring of Neural Circuits in the Motor Cortex in Mouse Models of Parkinson's Disease

    PubMed Central

    Lalchandani, Rupa R.; Cui, Yuting; Shu, Yu; Xu, Tonghui; Ding, Jun B.

    2015-01-01

    SUMMARY Dynamic adaptations in synaptic plasticity are critical for learning new motor skills and maintaining memory throughout life, which rapidly decline with Parkinson's disease (PD). Plasticity in the motor cortex is important for acquisition and maintenance of novel motor skills, but how the loss of dopamine in PD leads to disrupted structural and functional plasticity in the motor cortex is not well understood. Here, we utilized mouse models of PD and 2-photon imaging to show that dopamine depletion resulted in structural changes in the motor cortex. We further discovered that dopamine D1 and D2 receptor signaling were linked to selectively and distinctly regulating these aberrant changes in structural and functional plasticity. Our findings suggest that both D1 and D2 receptor signaling regulate motor cortex plasticity, and loss of dopamine results in atypical synaptic adaptations that may contribute to the impairment of motor performance and motor memory observed in PD. PMID:26237365

  10. Dissociated functional connectivity profiles for motor and attention deficits in acute right-hemisphere stroke.

    PubMed

    Baldassarre, Antonello; Ramsey, Lenny; Rengachary, Jennifer; Zinn, Kristi; Siegel, Joshua S; Metcalf, Nicholas V; Strube, Michael J; Snyder, Abraham Z; Corbetta, Maurizio; Shulman, Gordon L

    2016-07-01

    Strokes often cause multiple behavioural deficits that are correlated at the population level. Here, we show that motor and attention deficits are selectively associated with abnormal patterns of resting state functional connectivity in the dorsal attention and motor networks. We measured attention and motor deficits in 44 right hemisphere-damaged patients with a first-time stroke at 1-2 weeks post-onset. The motor battery included tests that evaluated deficits in both upper and lower extremities. The attention battery assessed both spatial and non-spatial attention deficits. Summary measures for motor and attention deficits were identified through principal component analyses on the raw behavioural scores. Functional connectivity in structurally normal cortex was estimated based on the temporal correlation of blood oxygenation level-dependent signals measured at rest with functional magnetic resonance imaging. Any correlation between motor and attention deficits and between functional connectivity in the dorsal attention network and motor networks that might spuriously affect the relationship between each deficit and functional connectivity was statistically removed. We report a double dissociation between abnormal functional connectivity patterns and attention and motor deficits, respectively. Attention deficits were significantly more correlated with abnormal interhemispheric functional connectivity within the dorsal attention network than motor networks, while motor deficits were significantly more correlated with abnormal interhemispheric functional connectivity patterns within the motor networks than dorsal attention network. These findings indicate that functional connectivity patterns in structurally normal cortex following a stroke link abnormal physiology in brain networks to the corresponding behavioural deficits. PMID:27225794

  11. Mutant TDP-43 in motor neurons promotes the onset and progression of ALS in rats

    PubMed Central

    Huang, Cao; Tong, Jianbin; Bi, Fangfang; Zhou, Hongxia; Xia, Xu-Gang

    2011-01-01

    Amyotrophic lateral sclerosis (ALS) is characterized by progressive motor neuron degeneration, which ultimately leads to paralysis and death. Mutation of TAR DNA binding protein 43 (TDP-43) has been linked to the development of an inherited form of ALS. Existing TDP-43 transgenic animals develop a limited loss of motor neurons and therefore do not faithfully reproduce the core phenotype of ALS. Here, we report the creation of multiple lines of transgenic rats in which expression of ALS-associated mutant human TDP-43 is restricted to either motor neurons or other types of neurons and skeletal muscle and can be switched on and off. All of these rats developed progressive paralysis reminiscent of ALS when the transgene was switched on. Rats expressing mutant TDP-43 in motor neurons alone lost more spinal motor neurons than rats expressing the disease gene in varying neurons and muscle cells, although these rats all developed remarkable denervation atrophy of skeletal muscles. Intriguingly, progression of the disease was halted after transgene expression was switched off; in rats with limited loss of motor neurons, we observed a dramatic recovery of motor function, but in rats with profound loss of motor neurons, we only observed a moderate recovery of motor function. Our finding suggests that mutant TDP-43 in motor neurons is sufficient to promote the onset and progression of ALS and that motor neuron degeneration is partially reversible, at least in mutant TDP-43 transgenic rats. PMID:22156203

  12. Big Savings from Smart Motors

    NASA Technical Reports Server (NTRS)

    1984-01-01

    Chesebrough-Pond's operates 32 plants across the nation and in those plants are more than 10,000 electric motors. In an effort to cut down on waste of electrical power used by these motors, Chesebrough organized a Corporate Advanced Technology Group to devise ways of improving productivity and cut manufacturing costs. Chesebrough used NASA's Marshall Space Flight Center's Power Factor Controller technology as a departure point for development of their own computerized motor controller that enables motors to operate at maximum efficiency regardless of the motor's applications or operating condition.

  13. The neural correlates of speech motor sequence learning.

    PubMed

    Segawa, Jennifer A; Tourville, Jason A; Beal, Deryk S; Guenther, Frank H

    2015-04-01

    Speech is perhaps the most sophisticated example of a species-wide movement capability in the animal kingdom, requiring split-second sequencing of approximately 100 muscles in the respiratory, laryngeal, and oral movement systems. Despite the unique role speech plays in human interaction and the debilitating impact of its disruption, little is known about the neural mechanisms underlying speech motor learning. Here, we studied the behavioral and neural correlates of learning new speech motor sequences. Participants repeatedly produced novel, meaningless syllables comprising illegal consonant clusters (e.g., GVAZF) over 2 days of practice. Following practice, participants produced the sequences with fewer errors and shorter durations, indicative of motor learning. Using fMRI, we compared brain activity during production of the learned illegal sequences and novel illegal sequences. Greater activity was noted during production of novel sequences in brain regions linked to non-speech motor sequence learning, including the BG and pre-SMA. Activity during novel sequence production was also greater in brain regions associated with learning and maintaining speech motor programs, including lateral premotor cortex, frontal operculum, and posterior superior temporal cortex. Measures of learning success correlated positively with activity in left frontal operculum and white matter integrity under left posterior superior temporal sulcus. These findings indicate speech motor sequence learning relies not only on brain areas involved generally in motor sequencing learning but also those associated with feedback-based speech motor learning. Furthermore, learning success is modulated by the integrity of structural connectivity between these motor and sensory brain regions. PMID:25313656

  14. Genetic variation in the 3′-UTR of CYP1A2, CYP2B6, CYP2D6, CYP3A4, NR1I2, and UGT2B7: potential effects on regulation by microRNA and pharmacogenomics relevance

    PubMed Central

    Swart, Marelize; Dandara, Collet

    2014-01-01

    Introduction: Pharmacogenomics research has concentrated on variation in genes coding for drug metabolizing enzymes, transporters and nuclear receptors. However, variation affecting microRNA could also play a role in drug response. This project set out to investigate potential microRNA target sites in 11 genes and the extent of variation in the 3′-UTR of six selected genes; CYP1A2, CYP2B6, CYP2D6, CYP3A4, NR1I2, and UGT2B7. Methods: Fifteen microRNA target prediction algorithms were used to identify microRNAs predicted to regulate 11 genes. The 3′-UTR of the 6 genes which topped the list of potential microRNA targets was sequenced in 30 black South Africans. In addition, genetic variants within these genes were investigated for interference with mRNA-microRNA interactions. Potential effects of observed variants were determined using in silico prediction tools. Results: The 11 genes coding for DMEs, transporters and nuclear receptors were predicted to be targets of microRNAs with CYP2B6, NR1I2 (PXR), CYP3A4, and CYP1A2, interacting with the most microRNAs. The majority of identified genetic variants were predicted to interfere with microRNA regulation. For example, the variant, rs1054190C in NR1I2 was predicted to result in the presence of a binding site for the microRNA miR-1250-5p, while the variant rs1054191G was predicted to result in the absence of a recognition site for miR-371b-3p, miR-4258 and miR-4707-3p. Fifteen of the seventeen, novel variants occurred within microRNA target sequences. Conclusion: The 3′-UTR harbors variation that is likely to influence regulation of specific genes by microRNA. In silico prediction followed by functional validation could aid in decoding the contribution of variation in the 3′-UTR, to some unexplained heritability that affects drug response. Understanding the specific role of each microRNA may lead to identification of markers for targeted therapy and therefore improve personalized drug treatment. PMID:24926315

  15. The Relationship between Social and Motor Cognition in Primary School Age-Children

    PubMed Central

    Kenny, Lorcan; Hill, Elisabeth; Hamilton, Antonia F. de C.

    2016-01-01

    There is increased interest in the relationship between motor skills and social skills in child development, with evidence that the mechanisms underlying these behaviors may be linked. We took a cognitive approach to this problem, and examined the relationship between four specific cognitive domains: theory of mind, motor skill, action understanding, and imitation. Neuroimaging and adult research suggest that action understanding and imitation are closely linked, but are somewhat independent of theory of mind and low-level motor control. Here, we test if a similar pattern is shown in child development. A sample of 101 primary school aged children with a wide ability range completed tests of IQ (Raven’s matrices), theory of mind, motor skill, action understanding, and imitation. Parents reported on their children’s social, motor and attention performance as well as developmental concerns. The results showed that action understanding and imitation correlate, with the latter having a weak link to motor control. Theory of mind was independent of the other tasks. These results imply that independent cognitive processes for social interaction (theory of mind) and for motor control can be identified in primary school age children, and challenge approaches that link all these domains together. PMID:26941685

  16. Quantifying Motor Experience in the Infant Brain: EEG Power, Coherence, and Mu Desynchronization

    PubMed Central

    Gonzalez, Sandy L.; Reeb-Sutherland, Bethany C.; Nelson, Eliza L.

    2016-01-01

    The emergence of new motor skills, such as reaching and walking, dramatically changes how infants engage with the world socially and cognitively. Several examples of how motor experience can cascade into cognitive and social development have been documented, yet a significant knowledge gap remains in our understanding of whether these observed behavioral changes are accompanied by underlying neural changes. We propose that electroencephalography (EEG) measures such as power, coherence, and mu desynchronization are optimal tools to quantify motor experience in the infant brain. In this mini-review, we will summarize existing infant research that has separately assessed the relation between motor, cognitive, or social development with coherence, power, or mu desynchronization. We will discuss how the reviewed neural changes seen in seemingly separate developmental domains may be linked based on existing behavioral evidence. We will further propose that power, coherence, and mu desynchronization be used in research exploring the links between motor experience and cognitive and social development. PMID:26925022

  17. Sexual motivation is reflected by stimulus-dependent motor cortex excitability

    PubMed Central

    Schecklmann, Martin; Engelhardt, Kristina; Konzok, Julian; Rupprecht, Rainer; Greenlee, Mark W.; Mokros, Andreas; Langguth, Berthold

    2015-01-01

    Sexual behavior involves motivational processes. Findings from both animal models and neuroimaging in humans suggest that the recruitment of neural motor networks is an integral part of the sexual response. However, no study so far has directly linked sexual motivation to physiologically measurable changes in cerebral motor systems in humans. Using transcranial magnetic stimulation in hetero- and homosexual men, we here show that sexual motivation modulates cortical excitability. More specifically, our results demonstrate that visual sexual stimuli corresponding with one’s sexual orientation, compared with non-corresponding visual sexual stimuli, increase the excitability of the motor cortex. The reflection of sexual motivation in motor cortex excitability provides evidence for motor preparation processes in sexual behavior in humans. Moreover, such interrelationship links theoretical models and previous neuroimaging findings of sexual behavior. PMID:25556214

  18. Prospective errors determine motor learning.

    PubMed

    Takiyama, Ken; Hirashima, Masaya; Nozaki, Daichi

    2015-01-01

    Diverse features of motor learning have been reported by numerous studies, but no single theoretical framework concurrently accounts for these features. Here, we propose a model for motor learning to explain these features in a unified way by extending a motor primitive framework. The model assumes that the recruitment pattern of motor primitives is determined by the predicted movement error of an upcoming movement (prospective error). To validate this idea, we perform a behavioural experiment to examine the model's novel prediction: after experiencing an environment in which the movement error is more easily predictable, subsequent motor learning should become faster. The experimental results support our prediction, suggesting that the prospective error might be encoded in the motor primitives. Furthermore, we demonstrate that this model has a strong explanatory power to reproduce a wide variety of motor-learning-related phenomena that have been separately explained by different computational models. PMID:25635628

  19. Motor proficiency relationships among siblings.

    PubMed

    Wrotniak, Brian H; Salvy, Sarah J; Lazarus, Laura; Epstein, Leonard H

    2009-02-01

    The purpose of this study was to examine motor proficiency relations of siblings. 23 sibling pairs ages 5 to 13 years were studied. Motor proficiency was assessed by the Bruininks-Oseretsky Test of Motor Proficiency-Short Form of 14 items, adjusting for Body Mass Index percentile, age, and sex. The association among siblings' overall motor proficiency was not statistically significant. When each of the 14 items in the test was examined separately, significant associations were found. Items positively associated among siblings included walking on a balance beam, tapping feet and making circles, and sorting shape cards. Copying a picture of overlapping pencils and making dots in circles were inversely related. The results indicate that siblings may share certain motor-skill components of balance, bilateral coordination, and upper limb speed or dexterity, but do not necessarily have the same global motor competence. Additional research is needed to explain relations in motor skills among siblings. PMID:19425452

  20. Motor learning by observing.

    PubMed

    Mattar, Andrew A G; Gribble, Paul L

    2005-04-01

    Learning complex motor behaviors like riding a bicycle or swinging a golf club is based on acquiring neural representations of the mechanical requirements of movement (e.g., coordinating muscle forces to control the club). Here we provide evidence that mechanisms matching observation and action facilitate motor learning. Subjects who observed a video depicting another person learning to reach in a novel mechanical environment (imposed by a robot arm) performed better when later tested in the same environment than subjects who observed similar movements but no learning; moreover, subjects who observed learning of a different environment performed worse. We show that this effect is not based on conscious strategies but instead depends on the implicit engagement of neural systems for movement planning and control. PMID:15820701

  1. Dynamically Timed Electric Motor

    NASA Technical Reports Server (NTRS)

    Casper, Ann M. (Inventor)

    1997-01-01

    A brushless DC motor including a housing having an end cap secured thereto. The housing encloses a rotor. a stator and a rotationally displaceable commutation board having sensors secured thereon and spaced around the periphery of the rotor. An external rotational force is applied to the commutation board for displacement of the sensors to various positions whereby varying feedback signals are generated by the positioning of the sensors relative to the rotating rotor. The commutation board is secured in a fixed position in response to feedback signals indicative of optimum sensor position being determined. The rotation of the commutation board and the securing of the sensors in the desired fixed position is accomplished without requiring the removal of the end cap and with the DC motor operating.

  2. Magnetostrictive direct drive motors

    NASA Technical Reports Server (NTRS)

    Naik, Dipak; Dehoff, P. H.

    1992-01-01

    A new rare earth alloy, Terfenol-D, combines low frequency operation and extremely high energy density with high magnetostriction. Its material properties make it suitable as a drive element for actuators requiring high output torque. The high strains, the high forces and the high controllability of Terfenol alloys provide a powerful and challenging basis for new ways to generate motion in actuators. Two prototypes of motors using Terfenol-D rods were developed at NASA Goddard. The basic principles of operation are provided of the motor along with other relevant details. A conceptual design of a torque limiting safety clutch/brake under development is illustrated. Also, preliminary design drawings of a linear actuator using Terfenol-D is shown.

  3. Dynamically timed electric motor

    NASA Technical Reports Server (NTRS)

    Casper, Ann M. (Inventor)

    1994-01-01

    The invention disclosed in this document is a brushless DC motor including a housing having an end cap secured thereto. The housing encloses a rotor, a stator and a rotationally displaceable commutation board having 5 sensors secured thereon and spaced around the periphery of the rotor. An external rotational force is applied to the commutation board for displacement of the sensors to various positions whereby varying feedback signals are generated by the positioning of the sensors relative to the rotating rotor. The commutation board is secured in a fixed position in response to feedback signals indicative of optimum sensor position being determined. The rotation of the commutation board and the securing of the sensors in the desired fixed position is accomplished without requiring the removal of the 5 end cap and with the DC motor operating.

  4. Motor skill acquisition.

    PubMed

    Higgins, S

    1991-02-01

    The purpose of this article is to provide a framework for understanding motor skill and the process by which it is acquired. A selective historical overview is presented to demonstrate how the study of movement is a necessary preliminary to the study of motor skill learning. The phenomenon of skill is explored as an inherent feature of goal-directed organisms whose effective functioning depends on achieving a degree of competence in solving problems that are encountered in the everyday world. The relationship between problems and solutions is discussed. Movement is examined as a problem-solving tool and as the means by which the individual expresses skill. Factors that influence the individual's level of skill are fully explored, along with the implications for functional behavior. The creative use of resources in problem solving is thoroughly examined, and tasks are discussed in terms of the demands imposed on the individual. PMID:1989008

  5. Advanced Motor Drives Studies

    NASA Technical Reports Server (NTRS)

    Ehsani, M.; Tchamdjou, A.

    1997-01-01

    This report presents an evaluation of advanced motor drive systems as a replacement for the hydrazine fueled APU units. The replacement technology must meet several requirements which are particular to the space applications and the Orbiter in general. Some of these requirements are high efficiency, small size, high power density. In the first part of the study several motors are compared, based on their characteristics and in light of the Orbiter requirements. The best candidate, the brushless DC is chosen because of its particularly good performance with regards to efficiency. Several power electronics drive technologies including the conventional three-phase hard switched and several soft-switched inverters are then presented. In the last part of the study, a soft-switched inverter is analyzed and compared to its conventional hard-switched counterpart. Optimal efficiency is a basic requirement for space applications and the soft-switched technology represents an unavoidable trend for the future.

  6. Ironless armature torque motor

    NASA Technical Reports Server (NTRS)

    Fisher, R. L.

    1972-01-01

    Four iron-less armature torque motors, four Hall device position sensor assemblies, and two test fixtures were fabricated. The design approach utilized samarium cobalt permanent magnets, a large airgap, and a three-phase winding in a stationary ironless armature. Hall devices were employed to sense rotor position. An ironless armature torque motor having an outer diameter of 4.25 inches was developed to produce a torque constant of 65 ounce-inches per ampere with a resistance of 20.5 ohms. The total weight, including structural elements, was 1.58 pounds. Test results indicated that all specifications were met except for generated voltage waveform. It is recommended that investigations be made concerning the generated voltage waveform to determine if it may be improved.

  7. Libert-E Motor

    ERIC Educational Resources Information Center

    Sieloff, Susan F.; Kinnunen, Raymond; Chevarley, Joseph

    2011-01-01

    Kei Yun Wong has big dreams. She has been entrusted with the United States launch of Libert-E Motor, a new line of Chinese-manufactured electric scooters. With only $750,000 of her original budget of $3 million left, she needs to make sure that the launch succeeds, as it represents the initial step in her desire to create the first Chinese global…

  8. EPDM rocket motor insulation

    NASA Technical Reports Server (NTRS)

    Guillot, David G. (Inventor); Harvey, Albert R. (Inventor)

    2004-01-01

    A novel and improved EPDM formulation for a solid propellant rocket motor is described wherein hexadiene EPDM monomer components are replaced by alkylidene norbornene components, and, with appropriate adjustment of curing and other additives, functionally required rheological and physical characteristics are achieved with the desired compatibility with any one of a plurality of solid filler materials, e.g., powder silica, carbon fibers or aramid fibers, and with appropriate adhesion and extended storage or shelf-life characteristics.

  9. EPDM rocket motor insulation

    NASA Technical Reports Server (NTRS)

    Guillot, David G. (Inventor); Harvey, Albert R. (Inventor)

    2003-01-01

    A novel and improved EPDM formulation for a solid propellant rocket motor is described wherein hexadiene EPDM monomer components are replaced by alkylidene norbornene components and with appropriate adjustment of curing and other additives functionally-required rheological and physical characteristics are achieved with the desired compatibility with any one of a plurality of solid filler materials, e.g. powder silica, carbon fibers or aramid fibers, and with appropriate adhesion and extended storage or shelf life characteristics.

  10. EPDM rocket motor insulation

    NASA Technical Reports Server (NTRS)

    Guillot, David G. (Inventor); Harvey, Albert R. (Inventor)

    2008-01-01

    A novel and improved EPDM formulation for a solid propellant rocket motor is described wherein hexadiene EPDM monomer components are replaced by alkylidene norbornene components, and, with appropriate adjustment of curing and other additives, functionally required rheological and physical characteristics are achieved with the desired compatibility with any one of a plurality of solid filler materials, e.g., powder silica, carbon fibers or aramid fibers, and with appropriate adhesion and extended storage or shelf-life characteristics.

  11. Hydraulic motor for cars

    SciTech Connect

    Gagnon, D.C.

    1986-09-02

    A hydraulic motor for a car is described comprising, in combination, an automotive vehicle engine for travel self-propulsion, including a block, a plurality of cylinders in the block, a piston slidable in each cylinder, a crankshaft in the block, a piston rod connected between the crankshaft and each of the pistons, a power take-off gear on the crankshaft for the travel self-propulsion, and the engine including a hydraulic means for driving the pistons in the cylinders.

  12. The St. Louis Motor

    NASA Astrophysics Data System (ADS)

    Greenslade, Thomas B.

    2011-10-01

    The St. Louis Motor, invented in 1909, is unique among physics apparatus for being named for a geographical place rather than a physicist. The sturdy little device (Fig. 1) has never been out of production. Any older school or physics department that has not done a catastrophic housecleaning in the last 20 years will certainly have a small flock of them in the back room.

  13. Dyspraxia, motor function and visual-motor integration in autism.

    PubMed

    Miller, M; Chukoskie, L; Zinni, M; Townsend, J; Trauner, D

    2014-08-01

    This project assessed dyspraxia in high-functioning school aged children with autism with a focus on Ideational Praxis. We examined the association of specific underlying motor function including eye movement with ideational dyspraxia (sequences of skilled movements) as well as the possible role of visual-motor integration in dyspraxia. We found that compared to IQ-, sex- and age-matched typically developing children, the children with autism performed significantly worse on: Ideational and Buccofacial praxis; a broad range of motor tests, including measures of simple motor skill, timing and accuracy of saccadic eye movements and motor coordination; and tests of visual-motor integration. Impairments in individual children with autism were heterogeneous in nature, although when we examined the praxis data as a function of a qualitative measure representing motor timing, we found that children with poor motor timing performed worse on all praxis categories and had slower and less accurate eye movements while those with regular timing performed as well as typical children on those same tasks. Our data provide evidence that both motor function and visual-motor integration contribute to dyspraxia. We suggest that dyspraxia in autism involves cerebellar mechanisms of movement control and the integration of these mechanisms with cortical networks implicated in praxis. PMID:24742861

  14. Dyspraxia, Motor Function and Visual-Motor Integration in Autism

    PubMed Central

    Miller, M.; Chukoskie, L.; Zinni, M.; Townsend, J.; Trauner, D.

    2014-01-01

    This project assessed dyspraxia in high-functioning school aged children with autism with a focus on Ideational Praxis. We examined the association of specific underlying motor function including eye movement with ideational dyspraxia (sequences of skilled movements) as well as the possible role of visual-motor integration in dyspraxia. We found that compared to IQ-, sex- and age-matched typically developing children, the children with autism performed significantly worse on: Ideational and Buccofacial praxis; a broad range of motor tests, including measures of simple motor skill, timing and accuracy of saccadic eye movements and motor coordination; and tests of visual-motor integration. Impairments in individual children with autism were heterogeneous in nature, although when we examined the praxis data as a function of a qualitative measure representing motor timing, we found that children with poor motor timing performed worse on all praxis categories and had slower and less accurate eye movements while those with regular timing performed as well as typical children on those same tasks. Our data provide evidence that both motor function and visual-motor integration contribute to dyspraxia. We suggest that dyspraxia in autism involves cerebellar mechanisms of movement control and the integration of these mechanisms with cortical networks implicated in praxis. PMID:24742861

  15. Motor Fuel Excise Taxes

    SciTech Connect

    2015-09-01

    A new report from the National Renewable Energy Laboratory (NREL) explores the role of alternative fuels and energy efficient vehicles in motor fuel taxes. Throughout the United States, it is common practice for federal, state, and local governments to tax motor fuels on a per gallon basis to fund construction and maintenance of our transportation infrastructure. In recent years, however, expenses have outpaced revenues creating substantial funding shortfalls that have required supplemental funding sources. While rising infrastructure costs and the decreasing purchasing power of the gas tax are significant factors contributing to the shortfall, the increased use of alternative fuels and more stringent fuel economy standards are also exacerbating revenue shortfalls. The current dynamic places vehicle efficiency and petroleum use reduction polices at direct odds with policies promoting robust transportation infrastructure. Understanding the energy, transportation, and environmental tradeoffs of motor fuel tax policies can be complicated, but recent experiences at the state level are helping policymakers align their energy and environmental priorities with highway funding requirements.

  16. A universal computer control system for motors

    NASA Technical Reports Server (NTRS)

    Szakaly, Zoltan F. (Inventor)

    1991-01-01

    A control system for a multi-motor system such as a space telerobot, having a remote computational node and a local computational node interconnected with one another by a high speed data link is described. A Universal Computer Control System (UCCS) for the telerobot is located at each node. Each node is provided with a multibus computer system which is characterized by a plurality of processors with all processors being connected to a common bus, and including at least one command processor. The command processor communicates over the bus with a plurality of joint controller cards. A plurality of direct current torque motors, of the type used in telerobot joints and telerobot hand-held controllers, are connected to the controller cards and responds to digital control signals from the command processor. Essential motor operating parameters are sensed by analog sensing circuits and the sensed analog signals are converted to digital signals for storage at the controller cards where such signals can be read during an address read/write cycle of the command processing processor.

  17. Kinesin-12 motors cooperate to suppress microtubule catastrophes and drive the formation of parallel microtubule bundles.

    PubMed

    Drechsler, Hauke; McAinsh, Andrew D

    2016-03-22

    Human Kinesin-12 (hKif15) plays a crucial role in assembly and maintenance of the mitotic spindle. These functions of hKif15 are partially redundant with Kinesin-5 (Eg5), which can cross-link and drive the extensile sliding of antiparallel microtubules. Although both motors are known to be tetramers, the functional properties of hKif15 are less well understood. Here we reveal how single or multiple Kif15 motors can cross-link, transport, and focus the plus-ends of intersecting microtubules. During transport, Kif15 motors step simultaneously along both microtubules with relative microtubule transport driven by a velocity differential between motor domain pairs. Remarkably, this differential is affected by the underlying intersection geometry: the differential is low on parallel and extreme on antiparallel microtubules where one motor domain pair becomes immobile. As a result, when intersecting microtubules are antiparallel, canonical transport of one microtubule along the other is allowed because one motor is firmly attached to one microtubule while it is stepping on the other. When intersecting microtubules are parallel, however, Kif15 motors can drive (biased) parallel sliding because the motor simultaneously steps on both microtubules that it cross-links. These microtubule rearrangements will focus microtubule plus-ends and finally lead to the formation of parallel bundles. At the same time, Kif15 motors cooperate to suppress catastrophe events at polymerizing microtubule plus-ends, raising the possibility that Kif15 motors may synchronize the dynamics of bundles that they have assembled. Thus, Kif15 is adapted to operate on parallel microtubule substrates, a property that clearly distinguishes it from the other tetrameric spindle motor, Eg5. PMID:26969727

  18. Kinesin-12 motors cooperate to suppress microtubule catastrophes and drive the formation of parallel microtubule bundles

    PubMed Central

    Drechsler, Hauke; McAinsh, Andrew D.

    2016-01-01

    Human Kinesin-12 (hKif15) plays a crucial role in assembly and maintenance of the mitotic spindle. These functions of hKif15 are partially redundant with Kinesin-5 (Eg5), which can cross-link and drive the extensile sliding of antiparallel microtubules. Although both motors are known to be tetramers, the functional properties of hKif15 are less well understood. Here we reveal how single or multiple Kif15 motors can cross-link, transport, and focus the plus-ends of intersecting microtubules. During transport, Kif15 motors step simultaneously along both microtubules with relative microtubule transport driven by a velocity differential between motor domain pairs. Remarkably, this differential is affected by the underlying intersection geometry: the differential is low on parallel and extreme on antiparallel microtubules where one motor domain pair becomes immobile. As a result, when intersecting microtubules are antiparallel, canonical transport of one microtubule along the other is allowed because one motor is firmly attached to one microtubule while it is stepping on the other. When intersecting microtubules are parallel, however, Kif15 motors can drive (biased) parallel sliding because the motor simultaneously steps on both microtubules that it cross-links. These microtubule rearrangements will focus microtubule plus-ends and finally lead to the formation of parallel bundles. At the same time, Kif15 motors cooperate to suppress catastrophe events at polymerizing microtubule plus-ends, raising the possibility that Kif15 motors may synchronize the dynamics of bundles that they have assembled. Thus, Kif15 is adapted to operate on parallel microtubule substrates, a property that clearly distinguishes it from the other tetrameric spindle motor, Eg5. PMID:26969727

  19. Performance Comparison between a Permanent Magnet Synchronous Motor and an Induction Motor as a Traction Motor for High Speed Train

    NASA Astrophysics Data System (ADS)

    Kondo, Minoru; Kawamura, Junya; Terauchi, Nobuo

    Performance tests are carried out to demonstrate the superiority of a permanent magnet synchronous motor to an induction motor as a traction motor for high-speed train. A prototype motor was manufactured by replacing the rotor of a conventional induction motor. The test results show that the permanent magnet motor is lighter, efficient and more silent than the induction motor because of the different rotor structure.

  20. Coordinated Switching of Bacterial Flagellar Motors: Evidence for Direct Motor-Motor Coupling?

    NASA Astrophysics Data System (ADS)

    Hu, Bo; Tu, Yuhai

    2013-04-01

    The swimming of Escherichia coli is powered by its multiple flagellar motors. Each motor spins either clockwise or counterclockwise, under the control of an intracellular regulator, CheY-P. There can be two mechanisms (extrinsic and intrinsic) to coordinate the switching of bacterial motors. The extrinsic one arises from the fact that different motors in the same cell sense a common input (CheY-P) which fluctuates near the motors’ response threshold. An alternative, intrinsic mechanism is direct motor-motor coupling which makes synchronized switching energetically favorable. Here, we develop simple models for both mechanisms and uncover their different hallmarks. A quantitative comparison to the recent experiments suggests that the direct coupling mechanism may be accountable for the observed sharp correlation between motors in a single Escherichia coli. Possible origins of this coupling (e.g., hydrodynamic interaction) are discussed.

  1. Imparting Motion to a Test Object Such as a Motor Vehicle in a Controlled Fashion

    NASA Technical Reports Server (NTRS)

    Southward, Stephen C. (Inventor); Reubush, Chandler (Inventor); Pittman, Bryan (Inventor); Roehrig, Kurt (Inventor); Gerard, Doug (Inventor)

    2014-01-01

    An apparatus imparts motion to a test object such as a motor vehicle in a controlled fashion. A base has mounted on it a linear electromagnetic motor having a first end and a second end, the first end being connected to the base. A pneumatic cylinder and piston combination have a first end and a second end, the first end connected to the base so that the pneumatic cylinder and piston combination is generally parallel with the linear electromagnetic motor. The second ends of the linear electromagnetic motor and pneumatic cylinder and piston combination being commonly linked to a mount for the test object. A control system for the linear electromagnetic motor and pneumatic cylinder and piston combination drives the pneumatic cylinder and piston combination to support a substantial static load of the test object and the linear electromagnetic motor to impart controlled motion to the test object.

  2. An Inverter-Driven Induction Motor System with a Deadlock Breaking Capability

    NASA Astrophysics Data System (ADS)

    Ichikawa, Takuto; Yoshida, Toshiya; Miyashita, Osamu

    Induction motors are very widely used in various industrial applications. In semiconductor manufacturing processes, deadlock failure of pumps may occur by the adhering of glass material contained in the gas to the rotor. This can lead to the shutdown of the manufacturing plant. Therefore, a countermeasure to prevent deadlocking of a motor is required. This paper proposes a method for generating an impulse torque in an induction motor fed by an inverter. The proposed inverter circuit is composed of a conventional inverter and a few additional relays. The on-and-off control of the relays supplies an appropriate magnetizing current and a large torque current from the dc-link capacitor. In experiment, a 1.5-kW cage-type induction motor generated a torque that was approximately seven times larger than the rated torque of the motor. This large impulse torque is useful for breaking the motor deadlock.

  3. Wind motor applications for transportation

    SciTech Connect

    Lysenko, G.P.; Grigoriev, B.V.; Karpin, K.B.

    1996-12-31

    Motion equation for a vehicle equipped with a wind motor allows, taking into account the drag coefficients, to determine the optimal wind drag velocity in the wind motor`s plane, and hence, obtain all the necessary data for the wind wheel blades geometrical parameters definition. This optimal drag velocity significantly differs from the flow drag velocity which determines the maximum wind motor power. Solution of the motion equation with low drag coefficients indicates that the vehicle speed against the wind may be twice as the wind speed. One of possible transportation wind motor applications is its use on various ships. A ship with such a wind motor may be substantially easier to steer, and if certain devices are available, may proceed in autonomous control mode. Besides, it is capable of moving within narrow fairways. The cruise speed of a sailing boat and wind-motored ship were compared provided that the wind velocity direction changes along a harmonic law with regard to the motion direction. Mean dimensionless speed of the wind-motored ship appears to be by 20--25% higher than that of a sailing boat. There was analyzed a possibility of using the wind motors on planet rovers in Mars or Venus atmospheric conditions. A Mars rover power and motor system has been assessed for the power level of 3 kW.

  4. Potential interactions among linguistic, autonomic, and motor factors in speech.

    PubMed

    Kleinow, Jennifer; Smith, Anne

    2006-05-01

    Though anecdotal reports link certain speech disorders to increases in autonomic arousal, few studies have described the relationship between arousal and speech processes. Additionally, it is unclear how increases in arousal may interact with other cognitive-linguistic processes to affect speech motor control. In this experiment we examine potential interactions between autonomic arousal, linguistic processing, and speech motor coordination in adults and children. Autonomic responses (heart rate, finger pulse volume, tonic skin conductance, and phasic skin conductance) were recorded simultaneously with upper and lower lip movements during speech. The lip aperture variability (LA variability index) across multiple repetitions of sentences that varied in length and syntactic complexity was calculated under low- and high-arousal conditions. High arousal conditions were elicited by performance of the Stroop color word task. Children had significantly higher lip aperture variability index values across all speaking tasks, indicating more variable speech motor coordination. Increases in syntactic complexity and utterance length were associated with increases in speech motor coordination variability in both speaker groups. There was a significant effect of Stroop task, which produced increases in autonomic arousal and increased speech motor variability in both adults and children. These results provide novel evidence that high arousal levels can influence speech motor control in both adults and children. PMID:16617462

  5. Motor excitability during movement preparation in Tourette syndrome

    PubMed Central

    Draper, Amelia; Jude, Lucinda; Jackson, Georgina M; Jackson, Stephen R

    2015-01-01

    Tourette syndrome (TS) is a neurodevelopmental disorder characterized by the occurrence of motor and vocal tics. TS has been linked to the impaired operation of cortical-striatal-thalamic-cortical circuits that give rise to hyper-excitability of cortical motor areas, which may be exacerbated by dysfunctional intra-cortical inhibitory mechanisms. That said, many individuals gain control over their tics during adolescence and it has been suggested that this increased control arises as a result of the development of mechanisms that operate to suppress corticospinal excitability (CSE) ahead of volitional movements. Here we used single-pulse transcranial magnetic stimulation (TMS) in conjunction with a manual Go/NoGo task to investigate alterations in CSE ahead of volitional movements in a group of adolescents with TS (N = 10). Our study demonstrated that CSE, as measured by TMS-induced motor-evoked potentials (MEPs), was significantly reduced in the TS group in the period immediately preceding a finger movement. More specifically, we show that individuals with TS, unlike their age-matched controls, do not exhibit the predicted increase in mean MEP amplitude and decrease in MEP variability that immediately precede the execution of volitional movements in typically developing young adults. Finally, we report that the magnitude of the rise in MEP amplitude across the movement preparation period in TS is significantly negatively correlated with clinical measures of motor tic severity, suggesting that individuals with severe motor tics are least able to modulate motor cortical excitability. PMID:24283505

  6. Motor excitability during movement preparation in Tourette syndrome.

    PubMed

    Draper, Amelia; Jude, Lucinda; Jackson, Georgina M; Jackson, Stephen R

    2015-03-01

    Tourette syndrome (TS) is a neurodevelopmental disorder characterized by the occurrence of motor and vocal tics. TS has been linked to the impaired operation of cortical-striatal-thalamic-cortical circuits that give rise to hyper-excitability of cortical motor areas, which may be exacerbated by dysfunctional intra-cortical inhibitory mechanisms. That said, many individuals gain control over their tics during adolescence and it has been suggested that this increased control arises as a result of the development of mechanisms that operate to suppress corticospinal excitability (CSE) ahead of volitional movements. Here we used single-pulse transcranial magnetic stimulation (TMS) in conjunction with a manual Go/NoGo task to investigate alterations in CSE ahead of volitional movements in a group of adolescents with TS (N = 10). Our study demonstrated that CSE, as measured by TMS-induced motor-evoked potentials (MEPs), was significantly reduced in the TS group in the period immediately preceding a finger movement. More specifically, we show that individuals with TS, unlike their age-matched controls, do not exhibit the predicted increase in mean MEP amplitude and decrease in MEP variability that immediately precede the execution of volitional movements in typically developing young adults. Finally, we report that the magnitude of the rise in MEP amplitude across the movement preparation period in TS is significantly negatively correlated with clinical measures of motor tic severity, suggesting that individuals with severe motor tics are least able to modulate motor cortical excitability. PMID:24283505

  7. Sleep and Motor Learning: Implications for Physical Rehabilitation After Stroke

    PubMed Central

    Gudberg, Christel; Johansen-Berg, Heidi

    2015-01-01

    Sleep is essential for healthy brain function and plasticity underlying learning and memory. In the context of physical impairment such as following a stroke, sleep may be particularly important for supporting critical recovery of motor function through similar processes of reorganization in the brain. Despite a link between stroke and poor sleep, current approaches to rehabilitative care often neglect the importance of sleep in clinical assessment and treatment. This review assimilates current evidence on the role of sleep in motor learning, with a focus on the implications for physical rehabilitation after stroke. We further outline practical considerations for integrating sleep assessment as a vital part of clinical care. PMID:26635718

  8. Comparison of capabilities of reluctance synchronous motor and induction motor

    NASA Astrophysics Data System (ADS)

    Štumberger, Gorazd; Hadžiselimović, Miralem; Štumberger, Bojan; Miljavec, Damijan; Dolinar, Drago; Zagradišnik, Ivan

    2006-09-01

    This paper compares the capabilities of a reluctance synchronous motor (RSM) with those of an induction motor (IM). An RSM and IM were designed and made, with the same rated power and speed. They differ only in the rotor portion while their stators, housings and cooling systems are identical. The capabilities of both motors in a variable speed drive are evaluated by comparison of the results obtained by magnetically nonlinear models and by measurements.

  9. Spontaneous Formation of a Globally Connected Contractile Network in a Microtubule-Motor System.

    PubMed

    Torisawa, Takayuki; Taniguchi, Daisuke; Ishihara, Shuji; Oiwa, Kazuhiro

    2016-07-26

    Microtubule (MT) networks play key roles in cell division, intracellular transport, and cell motility. These functions of MT networks occur through interactions between MTs and various associated proteins, notably motor proteins that bundle and slide MTs. Our objective in this study was to address the question of how motors determine the nature of MT networks. We conducted in vitro assays using homotetrameric kinesin Eg5, a motor protein involved in the formation and maintenance of the mitotic spindle. The mixing of Eg5 and MTs produced a range of spatiotemporal dynamics depending on the motor/filament ratio. Low motor/filament ratios produced globally connected static MT networks with sparsely distributed contractile active nodes (motor-accumulating points with radially extending MTs). Increasing the motor/filament ratio facilitated the linking of contractile active nodes and led to a global contraction of the network. When the motor/filament ratio was further increased, densely distributed active nodes formed local clusters and segmented the network into pieces with their strong contractile forces. Altering the properties of the motor through the use of chimeric Eg5, which has kinesin-1 heads, resulted in the generation of many isolated asters. These results suggest that the spatial distribution of contractile active nodes determines the dynamics of MT-motor networks. We then developed a coarse-grained model of MT-motor networks and identified two essential features for reproducing the experimentally observed patterns: an accumulation of motors that form the active nodes necessary to generate contractile forces, and a nonlinear dependency of contractile force on motor densities. Our model also enabled us to characterize the mechanical properties of the contractile network. Our study provides insight into how local motor-MT interactions generate the spatiotemporal dynamics of macroscopic network structures. PMID:27463139

  10. Learning piano melodies in visuo-motor or audio-motor training conditions and the neural correlates of their cross-modal transfer.

    PubMed

    Engel, Annerose; Bangert, Marc; Horbank, David; Hijmans, Brenda S; Wilkens, Katharina; Keller, Peter E; Keysers, Christian

    2012-11-01

    To investigate the cross-modal transfer of movement patterns necessary to perform melodies on the piano, 22 non-musicians learned to play short sequences on a piano keyboard by (1) merely listening and replaying (vision of own fingers occluded) or (2) merely observing silent finger movements and replaying (on a silent keyboard). After training, participants recognized with above chance accuracy (1) audio-motor learned sequences upon visual presentation (89±17%), and (2) visuo-motor learned sequences upon auditory presentation (77±22%). The recognition rates for visual presentation significantly exceeded those for auditory presentation (p<.05). fMRI revealed that observing finger movements corresponding to audio-motor trained melodies is associated with stronger activation in the left rolandic operculum than observing untrained sequences. This region was also involved in silent execution of sequences, suggesting that a link to motor representations may play a role in cross-modal transfer from audio-motor training condition to visual recognition. No significant differences in brain activity were found during listening to visuo-motor trained compared to untrained melodies. Cross-modal transfer was stronger from the audio-motor training condition to visual recognition and this is discussed in relation to the fact that non-musicians are familiar with how their finger movements look (motor-to-vision transformation), but not with how they sound on a piano (motor-to-sound transformation). PMID:22484310

  11. Multimotor Driven Cargos: From Single Motor under Load to the Role of Motor-Motor Coupling.

    PubMed

    Peker, Itay; Granek, Rony

    2016-07-01

    Motor proteins constitute an essential part of the cellular machinery. They have been the subject of intensive studies in the past two decades. Yet, when several motors simultaneously carry a single cargo, the effect of motor-motor coupling, such as mutual stalling and jamming, remains unclear. We commence by constructing a general model for single motor motion, which is a product of a derived load-dependent expression and a phenomenological motor specific function. Forming the latter according to recent single molecule measurements for a given load, the model correctly predicts the motor full step-size distribution for all other measured loads. We then use our proposed model to predict transport properties of multimotor complexes, with particular attention to 1-dimensional constructs with variable flexibility, motor density, and number of motors: (i) a chain of motors connected by springs, a recently studied construction of a pair, and (ii) an array of motors all connected by identical springs to a stiff rod, which is essentially a mirror image of standard gliding motility assays. In both systems, and for any number of carrying motors, we find that, while low flexibility results in a strongly damped velocity, increased flexibility renders an almost single motor velocity. Comparing our model based simulations to recent gliding assays we find remarkable qualitative agreement. We also demonstrate consistency with other multimotor motility assays. In all cases, the characteristic spring constant, that controls the crossover behavior between high and low velocity regimes, is found to be the stalling force divided by the mean step size. We conjecture that this characteristic spring constant can serve as a tool for engineering multimotor complexes. PMID:27044876

  12. Bearingless switched reluctance motor

    NASA Technical Reports Server (NTRS)

    Morrison, Carlos R. (Inventor)

    2004-01-01

    A switched reluctance motor has a stator with a first set of poles directed toward levitating a rotor horizontally within the stator. A disc shaped portion of a hybrid rotor is affected by the change in flux relative to the current provided at these levitation poles. A processor senses the position of the rotor and changes the flux to move the rotor toward center of the stator. A second set of poles of the stator are utilized to impart torque upon a second portion of the rotor. These second set of poles are driven in a traditional switched reluctance manner by the processor.

  13. Redundant motor drive system

    NASA Technical Reports Server (NTRS)

    Calvert, J. A. (Inventor)

    1980-01-01

    A drive system characterized by a base supporting a pair of pillars arranged in spaced parallelism, a shaft extended between and supported by the pillars for rotation about the longitudinal axis thereof, a worm gear affixed to the shaft and supported in coaxial relation therewith is described. A bearing housing of a sleeve like configuration is concentrically related to the shaft and is supported thereby for free rotation. A first and a second quiescent drive train, alternatively activatable, is provided for imparting rotation into said bearing housing. Each of the drive trains is characterized by a selectively energizable motor connected to a spur gear.

  14. [Esophageal motor disturbances in sclerodermia].

    PubMed

    Stanciu, C; Cijevschi, C; Dobrescu, A; Petrescu, Z

    1981-01-01

    By the manometric method the esophageal motility in 14 patients with sclerodermia was studied. All patients presented an esophageal motor dysfunction characterized by the decrease in amplitude of the spohageal contractions, presence of aperistaltic contractions, decrease of basal pressure of the lower esophageal sphincter and its incomplete relaxation at deglutition. These esophageal motor disturbances may appear in association or separately in the same patient. The pathogenesis of the esophageal motor dysfunction in sclerodermia is not yet fully understood. Besides the theoretical interest, the knowledge of the esophageal motor dysfunction in sclerodermia has also a practical value in respect of the tretment which is to be set up. PMID:25528800

  15. Linking | Smokefree.gov

    Cancer.gov

    Links to individual pages within the Smokefree.gov Web site are permissible, provided attribution is made to Smokefree.gov and any descriptive notes accurately reflect the content of the linked page(s).

  16. 76 FR 12792 - Petition for Exemption From the Federal Motor Vehicle Motor Theft Prevention Standard; General...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-03-08

    ... TRANSPORTATION National Highway Traffic Safety Administration Petition for Exemption From the Federal Motor Vehicle Motor Theft Prevention Standard; General Motors Corporation AGENCY: National Highway Traffic.... SUMMARY: This document grants in full the petition of General Motors Corporation's (GM) petition for...

  17. 30 CFR 18.34 - Motors.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... PRODUCTS ELECTRIC MOTOR-DRIVEN MINE EQUIPMENT AND ACCESSORIES Construction and Design Requirements § 18.34 Motors. Explosion-proof electric motor assemblies intended for use in approved equipment in underground...) Small motors (alternating- and direct-current). Motors having internal free volume not exceeding...

  18. Infranuclear ocular motor disorders.

    PubMed

    Lueck, Christian J

    2011-01-01

    This chapter covers the very large number of possible disorders that can affect the three ocular motor nerves, the neuromuscular junction, or the extraocular muscles. Conditions affecting the nerves are discussed under two major headings: those in which the site of damage can be anatomically localized (e.g., fascicular lesions and lesions occurring in the subarachnoid space, the cavernous sinus, the superior orbital fissure, or the orbit) and those in which the site of the lesion is either nonspecific or variable (e.g., vascular lesions, tumors, "ophthalmoplegic migraine," and congenital disorders). Specific comments on the diagnosis and management of disorders of each of the three nerves follow. Ocular motor synkineses (including Duane's retraction syndrome and aberrant regeneration) and disorders resulting in paroxysms of excess activity (e.g., neuromyotonia) are then covered, followed by myasthenia gravis and other disorders that affect the neuromuscular junction. A final section discusses disorders of the extraocular muscles themselves, including thyroid disease, orbital myositis, mitochondrial disease, and the muscular dystrophies. PMID:21601071

  19. 27. View, looking north, of motor house; the electric motor ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    27. View, looking north, of motor house; the electric motor and electric-powered winch are housed in section of building to the left. Photo by Jet Lowe, HAER, 1989. - Puget Sound Power & Light Company, White River Hydroelectric Project, 600 North River Avenue, Dieringer, Pierce County, WA

  20. Motor vehicle drivers' injuries in train-motor vehicle crashes.

    PubMed

    Zhao, Shanshan; Khattak, Aemal

    2015-01-01

    The objectives of this research were to: (1) identify a more suitable model for modeling injury severity of motor vehicle drivers involved in train-motor vehicle crashes at highway-rail grade crossings from among three commonly used injury severity models and (2) to investigate factors associated with injury severity levels of motor vehicle drivers involved in train-motor vehicle crashes at such crossings. The 2009-2013 highway-rail grade crossing crash data and the national highway-rail crossing inventory data were combined to produce the analysis dataset. Four-year (2009-2012) data were used for model estimation while 2013 data were used for model validation. The three injury severity levels-fatal, injury and no injury-were based on the reported intensity of motor-vehicle drivers' injuries at highway-rail grade crossings. The three injury severity models evaluated were: ordered probit, multinomial logit and random parameter logit. A comparison of the three models based on different criteria showed that the random parameter logit model and multinomial logit model were more suitable for injury severity analysis of motor vehicle drivers involved in crashes at highway-rail grade crossings. Some of the factors that increased the likelihood of more severe crashes included higher train and vehicle speeds, freight trains, older drivers, and female drivers. Where feasible, reducing train and motor vehicle speeds and nighttime lighting may help reduce injury severities of motor vehicle drivers. PMID:25463957

  1. Motor power control circuit for ac induction motors

    NASA Technical Reports Server (NTRS)

    Nola, F. J. (Inventor)

    1983-01-01

    A motor power control of the type which functions by controlling the power factor wherein one of the parameters of power factor current on time is determined by the on time of a triac through which current is supplied to the motor. By means of a positive feedback circuit, a wider range of control is effected.

  2. Motor-operated valve (MOV) actuator motor and gearbox testing

    SciTech Connect

    DeWall, K.; Watkins, J.C.; Bramwell, D.

    1997-07-01

    Researchers at the Idaho National Engineering and Environmental Laboratory tested the performance of electric motors and actuator gearboxes typical of the equipment installed on motor-operated valves used in nuclear power plants. Using a test stand that simulates valve closure loads against flow and pressure, the authors tested five electric motors (four ac and one dc) and three gearboxes at conditions a motor might experience in a power plant, including such off-normal conditions as operation at high temperature and reduced voltage. They also monitored the efficiency of the actuator gearbox. All five motors operated at or above their rated starting torque during tests at normal voltages and temperatures. For all five motors, actual torque losses due to voltage degradation were greater than the losses calculated by methods typically used for predicting motor torque at degraded voltage conditions. For the dc motor the actual torque losses due to elevated operating temperatures were greater than the losses calculated by the typical predictive method. The actual efficiencies of the actuator gearboxes were generally lower than the running efficiencies published by the manufacturer and were generally nearer the published pull-out efficiencies. Operation of the gearbox at elevated temperature did not affect the operating efficiency.

  3. Commercial Web Site Links.

    ERIC Educational Resources Information Center

    Thelwall, Mike

    2001-01-01

    Discusses business use of the Web and related search engine design issues as well as research on general and academic links before reporting on a survey of the links published by a collection of business Web sites. Results indicate around 66% of Web sites do carry external links, most of which are targeted at a specific purpose, but about 17%…

  4. Sensory and motor neuropathy in a Border Collie.

    PubMed

    Harkin, Kenneth R; Cash, Walter C; Shelton, G Diane

    2005-10-15

    A 5-month-old female Border Collie was evaluated because of progressive hind limb ataxia. The predominant clinical findings suggested a sensory neuropathy. Sensory nerve conduction velocity was absent in the tibial, common peroneal, and radial nerves and was decreased in the ulnar nerve; motor nerve conduction velocity was decreased in the tibial, common peroneal, and ulnar nerves. Histologic examination of nerve biopsy specimens revealed considerable nerve fiber depletion; some tissue sections had myelin ovoids, foamy macrophages, and axonal degeneration in remaining fibers. Marked depletion of most myelinated fibers within the peroneal nerve (a mixed sensory and motor nerve) supported the electrodiagnostic findings indicative of sensorimotor neuropathy. Progressive deterioration in motor function occurred over the following 19 months until the dog was euthanatized. A hereditary link was not established, but a littermate was similarly affected. The hereditary characteristic of this disease requires further investigation. PMID:16266014

  5. The Motor System Contributes to Comprehension of Abstract Language

    PubMed Central

    Guan, Connie Qun; Meng, Wanjin; Yao, Ru; Glenberg, Arthur M.

    2013-01-01

    If language comprehension requires a sensorimotor simulation, how can abstract language be comprehended? We show that preparation to respond in an upward or downward direction affects comprehension of the abstract quantifiers “more and more” and “less and less” as indexed by an N400-like component. Conversely, the semantic content of the sentence affects the motor potential measured immediately before the upward or downward action is initiated. We propose that this bidirectional link between motor system and language arises because the motor system implements forward models that predict the sensory consequences of actions. Because the same movement (e.g., raising the arm) can have multiple forward models for different contexts, the models can make different predictions depending on whether the arm is raised, for example, to place an object or raised as a threat. Thus, different linguistic contexts invoke different forward models, and the predictions constitute different understandings of the language. PMID:24086463

  6. Stability of solid rocket motor with spray-liquid

    NASA Astrophysics Data System (ADS)

    Wang, Liang; Hu, Naihe

    1992-12-01

    Dynamic equations were developed for every link of the feedback control system of a solid rocket motor (SRM) with fuel injection. Using transfer functions and the parameter stability theory, equilibrium steady boundary equations and steady criteria were obtained and solved. It is shown that, the injection ratio, the pressure exponent, and tank pressure are the main design parameters affecting stability; therefore, the stability analysis of an SRM with fuel injection should concentrate on the initial phase of the motor operation. It was found that the motor stability of an SRM with fuel injection improves with the increase of the injection ratio, the free volume of the combustion chamber, and the value of the pressure exponent.

  7. Retention of Motor Skills: Review.

    ERIC Educational Resources Information Center

    Schendel, J. D.; And Others

    A summary of an extensive literature survey deals with the variables known or suspected to affect the retention of learned motor behaviors over lengthy no-practice intervals. Emphasis was given to research conducted by or for the military. The variables that may affect the retention of motor skills were dichotomized into task variables and…

  8. Conical Bearingless Motor/Generators

    NASA Technical Reports Server (NTRS)

    Kascak, P.; Jansen, R.; Dever, T.

    2008-01-01

    Motor/generators based on conical magnetic bearings have been invented as an improved alternative to prior such machines based, variously, on radial and/or axial magnetic bearings. Both the present and prior machines are members of the class of so-called bearingless or self bearing (in the sense of not containing mechanical bearings) rotary machines. Each motor/generator provides both a torque and force allowing it to either function as a motor and magnetic bearing or a generator and magnetic bearing concurrently. Because they are not subject to mechanical bearing wear, these machines have potentially long operational lives and can function without lubrication and over wide ranges of speed and temperature that include conditions under which lubricants would become depleted, degraded, or ineffective and mechanical bearings would fail. The figure shows three typical configurations of conical bearingless motor/generators. The main elements of each motor/generator are concentric rotor and stator portions having conically tapered surfaces facing each other across a gap. Because a conical motor/generator imposes both radial and axial magnetic forces, it acts, in effect, as a combination of an axial and a radial magnetic bearing. Therefore, only two conical motor/generators - one at each end of a rotor - are needed to effect complete magnetic leviation of the rotor, whereas previously, it was necessary to use a combination of an axial and a radial magnetic bearing at each end of the rotor to achieve complete magnetic levitation and a separate motor to provide torque.

  9. [Motor neuron disease: metabolic evaluation].

    PubMed

    Godoy, J M; Skacel, M; Balassiano, S L; Neves, J R

    1992-03-01

    The authors studied serum and urinary calcium and phosphorus levels, as well as abnormalities on the spine of 30 patients with motor neuron disease. The authors believe in multifactorial aspects in the pathogenesis of motor neuron disease, calling special attention to toxic and metabolic factors. PMID:1307483

  10. Power control for ac motor

    NASA Technical Reports Server (NTRS)

    Dabney, R. W. (Inventor)

    1984-01-01

    A motor controller employing a triac through which power is supplied to a motor is described. The open circuit voltage appearing across the triac controls the operation of a timing circuit. This timing circuit triggers on the triac at a time following turn off which varies inversely as a function of the amplitude of the open circuit voltage of the triac.

  11. Torque control for electric motors

    NASA Technical Reports Server (NTRS)

    Bernard, C. A.

    1980-01-01

    Method for adjusting electric-motor torque output to accomodate various loads utilizes phase-lock loop to control relay connected to starting circuit. As load is imposed, motor slows down, and phase lock is lost. Phase-lock signal triggers relay to power starting coil and generate additional torque. Once phase lock is recoverd, relay restores starting circuit to its normal operating mode.

  12. Alternative Motor Fuel Use Model

    Energy Science and Technology Software Center (ESTSC)

    1992-11-16

    AMFU is a tool for the analysis and prediction of motor fuel use by highway vehicles. The model advances the art of vehicle stock modeling by including a representation of the choice of motor fuel for flexible and dual fuel vehicles.

  13. Advanced solid propellant motor insulation

    NASA Technical Reports Server (NTRS)

    Smith, P. L.; Russ, R. F.

    1972-01-01

    An advanced lightweight insulation system suitable for use in long duration, low pressure planetary orbiter-type motor applications was developed. Experiments included the screening of various filler and binder materials with optimization studies combining the best of each. Small scale test motor data were used to judge the degree of success.

  14. Computational approaches to motor control

    PubMed Central

    Flash, Tamar; Sejnowski, Terrence J

    2010-01-01

    New concepts and computational models that integrate behavioral and neurophysiological observations have addressed several of the most fundamental long-standing problems in motor control. These problems include the selection of particular trajectories among the large number of possibilities, the solution of inverse kinematics and dynamics problems, motor adaptation and the learning of sequential behaviors. PMID:11741014

  15. Motor Coordination and Executive Functions

    ERIC Educational Resources Information Center

    Michel, Eva

    2012-01-01

    Since Piaget, the view that motor and cognitive development are interrelated has gained wide acceptance. However, empirical research on this issue is still rare. Few studies show a correlation of performance in cognitive and motor tasks in typically developing children. More specifically, Diamond A. (2000) hypothesizes an involvement of executive…

  16. Motors and Bulbs in Series

    ERIC Educational Resources Information Center

    Whitaker, Robert J.

    2009-01-01

    One of Paul Hewitt's "Figuring Physics" that appeared in this journal dealt with the heating of a motor. This phenomenon can be demonstrated with a miniature motor and a bulb as part of a series of activities with "batteries and bulbs." Students examine the effect on the brightness of a single bulb when a second, identical bulb is placed in series…

  17. Industrial motor repair in the United States

    SciTech Connect

    Schueler, V.; Leistner, P.; Douglass, J.

    1994-09-01

    This report characterizes the motor repair industry in the United States; summarizes current motor repair and testing practice; and identifies barriers to energy motor repair practice and recommends strategies for overcoming those barriers.

  18. Developmental exposure to polychlorinated biphenyls 52, 138 or 180 affects differentially learning or motor coordination in adult rats. Mechanisms involved.

    PubMed

    Boix, J; Cauli, O; Felipo, V

    2010-06-01

    Exposure to polychlorinated biphenyls (PCBs) during pregnancy and lactation leads to cognitive impairment and motor disorders in children by mechanisms which remain unknown. It also remains unclear whether different non-dioxin-like PCBs have similar or different mechanisms of neurotoxicity. The main aims of this work were: (1) to assess whether developmental exposure to non-dioxin-like-PCBs 52, 138 or 180 affect cognitive function or motor coordination in 3-4 months-old rats; (2) to shed light on the underlying mechanisms. Female rats were treated with PCBs (1 mg/kg day) in food from gestational-day 7 to postnatal-day 21. The ability to learn a Y maze conditional discrimination task was reduced in rats exposed to PCBs 138 or 180, but not in rats exposed to PCB52. The function of the glutamate-nitric oxide-cGMP pathway (NMDA-induced increase in extracellular cGMP) in cerebellum in vivo was reduced by 33-59% in rats exposed to PCBs 138 or 180, but not by PCB52. The amount of NR1 subunit of NMDA receptors was reduced by 41-49% in rats exposed to PCBs 138 or 180, but not by PCB 52. PCB52 but not 138 or 180 increases extracellular GABA in cerebellum and impairs motor coordination. The effects were similar in males and females. Developmental exposure to different non-dioxin-like PCBs induces different behavioural alterations by different mechanisms. PCB52 impairs motor coordination but not learning while PCB138 or 180 impair learning but not motor coordination. These data are consistent with the following possible mechanisms: (1) developmental exposure to PCBs 138 or 180 reduces the amount of NMDA receptors in cerebellum, which would contribute to reduced function of the glutamate-NO-cGMP pathway, which, in turn, would be a main contributor to the impairment of the ability to learn the Y maze task. (2) Developmental exposure to PCB52 increases extracellular GABA in cerebellum, which would contribute to motor coordination impairment. PMID:20223283

  19. Motor-operated gearbox efficiency

    SciTech Connect

    DeWall, K.G.; Watkins, J.C.; Bramwell, D.; Weidenhamer, G.H.

    1996-12-01

    Researchers at the Idaho National Engineering Laboratory recently conducted tests investigating the operating efficiency of the power train (gearbox) in motor-operators typically used in nuclear power plants to power motor-operated valves. Actual efficiency ratios were determined from in-line measurements of electric motor torque (input to the operator gearbox) and valve stem torque (output from the gearbox) while the operators were subjected to gradually increasing loads until the electric motor stalled. The testing included parametric studies under reduced voltage and elevated temperature conditions. As part of the analysis of the results, the authors compared efficiency values determined from testing to the values published by the operator manufacturer and typically used by the industry in calculations for estimating motor-operator capabilities. The operators they tested under load ran at efficiencies lower than the running efficiency (typically 50%) published by the operator manufacturer.

  20. Motor-operator gearbox efficiency

    SciTech Connect

    DeWall, K.G.; Watkins, J.C.; Bramwell, D.

    1996-06-01

    Researchers at the Idaho National Engineering Laboratory recently conducted tests investigating the operating efficiency of the power train (gearbox) in motor-operators typically used in nuclear power plants to power motor-operated valves. Actual efficiency ratios were determined from in-line measurements of electric motor torque (input to the operator gearbox) and valve stem torque (output from the gearbox) while the operators were subjected to gradually increasing loads until the electric motor stalled. The testing included parametric studies under reduced voltage and elevated temperature conditions. As part of the analysis of the results, we compared efficiency values determined from testing to the values published by the operator manufacturer and typically used by the industry in calculations for estimating motor-operator capabilities. The operators we tested under load ran at efficiencies lower than the running efficiency (typically 50%) published by the operator manufacturer.

  1. Reciprocating linear motor

    NASA Technical Reports Server (NTRS)

    Goldowsky, Michael P. (Inventor)

    1987-01-01

    A reciprocating linear motor is formed with a pair of ring-shaped permanent magnets having opposite radial polarizations, held axially apart by a nonmagnetic yoke, which serves as an axially displaceable armature assembly. A pair of annularly wound coils having axial lengths which differ from the axial lengths of the permanent magnets are serially coupled together in mutual opposition and positioned with an outer cylindrical core in axial symmetry about the armature assembly. One embodiment includes a second pair of annularly wound coils serially coupled together in mutual opposition and an inner cylindrical core positioned in axial symmetry inside the armature radially opposite to the first pair of coils. Application of a potential difference across a serial connection of the two pairs of coils creates a current flow perpendicular to the magnetic field created by the armature magnets, thereby causing limited linear displacement of the magnets relative to the coils.

  2. Magnetic bearing and motor

    NASA Technical Reports Server (NTRS)

    Studer, Philip A. (Inventor)

    1983-01-01

    A magnetic bearing assembly (10) has an intermediate rotatable section (33) having an outer cylindrical member (30) coaxially suspended by a torsion wire (72) around an axially polarized cylindrical magnet (32). Axial alignment between the pole faces (40-43) of the intermediate section (33) and end surfaces (50-53) of opposed end bells (20, 22) provides a path of least reluctance across intervening air gaps (60-63) for the magnetic flux emanating from magnet (32). Radial dislocation increases the reluctance and creates a radial restoring force. Substitution of radially polarized magnets 107 fixed to a magnetically permeable cylinder (32') and insertion of pairs of armature coil windings (109-112) between the cylinder pair (33') provides an integral magnetic bearing and torsion motor (100) able to provide arcuately limited rotational drive.

  3. Piezoelectric wave motor

    DOEpatents

    Yerganian, Simon Scott

    2001-07-17

    A piezoelectric motor having a stator in which piezoelectric elements are contained in slots formed in the stator transverse to the desired wave motion. When an electric field is imposed on the elements, deformation of the elements imposes a force perpendicular to the sides of the slot, deforming the stator. Appropriate frequency and phase shifting of the electric field will produce a wave in the stator and motion in a rotor. In a preferred aspect, the piezoelectric elements are configured so that deformation of the elements in direction of an imposed electric field, generally referred to as the d.sub.33 direction, is utilized to produce wave motion in the stator. In a further aspect, the elements are compressed into the slots so as to minimize tensile stresses on the elements in use.

  4. Piezoelectric wave motor

    DOEpatents

    Yerganian, Simon Scott

    2003-02-11

    A piezoelectric motor having a stator in which piezoelectric elements are contained in slots formed in the stator transverse to the desired wave motion. When an electric field is imposed on the elements, deformation of the elements imposes a force perpendicular to the sides of the slot, deforming the stator. Appropriate frequency and phase-shifting of the electric field will produce a wave in the stator and motion in a rotor. In a preferred aspect, the piezoelectric elements are configured so that deformation of the elements in the direction of an imposed electric field, generally referred to as the d.sub.33 direction, is utilized to produce wave motion in the stator. In a further aspect, the elements are compressed into the slots so as to minimize tensile stresses on the elements in use.

  5. Magnetostrictive roller drive motor

    NASA Astrophysics Data System (ADS)

    Vranish, John M.

    1992-01-01

    A magnetostrictive drive motor is disclosed which has a rotary drive shaft in the form of a drum which is encircled by a plurality of substantially equally spaced roller members in the form of two sets of cones which are in contact with the respective cam surfaces on the inside surface of an outer drive ring. The drive ring is attached to sets of opposing pairs of magnetostrictive rods. Each rod in a pair is mutually positioned end to end within respective energizing coils. When one of the coils in an opposing pair is energized, the energized rod expands while the other rod is caused to contract, causing the drive ring to rock, i.e., rotate slightly in either the clockwise or counterclockwise direction, depending upon which rod in a pair is energized. As the drive ring is activated in repetitive cycles in either direction, one set of drive cones attempts to roll up their respective cam surface but are pinned between the drive shaft drum and the drive ring. As the frictional force preventing sliding builds up, the cones become locked, setting up reaction forces including a tangential component which is imparted to the drive shaft drum to provide a source of motor torque. Simultaneously the other set of cones are disengaged from the drive shaft drum. Upon deactivation of the magnetostrictive rod coils, the force on the drive cones is released, causing the system to return to an initial rest position. By repetitively cycling the energization of the magnetostrictive rods, the drive shaft drum indexes in microradian rotational steps.

  6. Closed-Loop Motor-Speed Control

    NASA Technical Reports Server (NTRS)

    Smith, Matthew A.; Delcher, Ray C.; Huston, Steven W.

    1989-01-01

    Electronic motor-speed control circuit designed to operate in electrically noisy environment. Includes optoelectronic pick-up device, placed inside motor housing to provide speed feedback signal. Automatically maintains speed motor at commanded value. Measures speed of motor in terms of frequency of pulses of infrared light chopped by fan blades of motor. Difference between measured and commanded speeds serves as control signal for external amplifier driving motor. Major advantage of circuit is low cost.

  7. Molecular motors and the 2nd law of thermodynamics

    NASA Astrophysics Data System (ADS)

    Wang, Zhisong

    2014-03-01

    Molecular motors from biology and nanotechnology often operate on chemical energy of fuel molecules in an isothermal environment, unlike macroscopic heat engines that draw energy from a heat flow between two temperatures. Nevertheless, isothermal molecular motors are still subject to the 2nd law of thermodynamics in a fundamental way: their directional motion must cost a finite amount of energy other than the environmental heat even though no work is done; otherwise the 2nd law would be violated. Hence the 2nd law requires a finite energy price for pure direction of molecular motors. But what is the lowest price of direction allowed by the 2nd law? And how does the 2nd law-decreed price of direction limit performance of molecular motors? In the talk, I shall present our theoretical study of the 2nd law-molecular motor link on basis of the accumulated biomotor phenomenology, and also introduce our experimental effort to develop biomimetic DNA bipedal nanomotors following the mechanistic guidelines out of the theoretical study. [Main contents of this talk are from references:] This work is partially supported by FRC grants R-144-000-259-112, R-144-000-290-112 and R-144-000-320-112.

  8. Pattern Formations in Polymer-Molecular Motor Networks

    NASA Astrophysics Data System (ADS)

    Smith, David; Humphrey, David; Duggan, Cynthia; Käs, Josef

    2001-03-01

    In previous studies with the microtubule-kinesin system, organized patterns such as asters and rotating vortices have been seen (Nedelec et al, Nature 1997), which were of a dynamic nature and dependent on active motors. A similar system was constructed using actin and myosin, which displays similar patterns, however, with drastically different dynamics. These patterns arise independent of the initial amount of immediate use energy (in the form of ATP), assembling only upon the near exhaustion of available ATP. Further studies have clearly shown that in fact these patterns are not dependent upon the motor activity of the myosin but its propensity to serve as a cross-linking element in an actin network, with the motor activity serving to prevent the arising of order in the system. We believe the dynamic differences inherent between the two polymer-motor systems studied lies primarily in the structural nature of the motor complexes, with the kinesin complex ordering the system by pushing multiple filaments in a parallel direction, and the myosin complexes disordering the system by pushing filaments in an antiparallel manner.

  9. Thalamic noradrenaline in Parkinson's disease: deficits suggest role in motor and non-motor symptoms.

    PubMed

    Pifl, Christian; Kish, Stephen J; Hornykiewicz, Oleh

    2012-11-01

    The thalamus occupies a pivotal position within the corticobasal ganglia-cortical circuits. In Parkinson's disease (PD), the thalamus exhibits pathological neuronal discharge patterns, foremost increased bursting and oscillatory activity, which are thought to perturb the faithful transfer of basal ganglia impulse flow to the cortex. Analogous abnormal thalamic discharge patterns develop in animals with experimentally reduced thalamic noradrenaline; conversely, added to thalamic neuronal preparations, noradrenaline exhibits marked antioscillatory and antibursting activity. Our study is based on this experimentally established link between noradrenaline and the quality of thalamic neuronal discharges. We analyzed 14 thalamic nuclei from all functionally relevant territories of 9 patients with PD and 8 controls, and measured noradrenaline with high-performance liquid chromatography with electrochemical detection. In PD, noradrenaline was profoundly reduced in all nuclei of the motor (pallidonigral and cerebellar) thalamus (ventroanterior: -86%, P = .0011; ventrolateral oral: -87%, P = .0010; ventrolateral caudal: -89%, P = .0014): Also, marked noradrenaline losses, ranging from 68% to 91% of controls, were found in other thalamic territories, including associative, limbic and intralaminar regions; the primary sensory regions were only mildly affected. The marked noradrenergic deafferentiation of the thalamus discloses a strategically located noradrenergic component in the overall pathophysiology of PD, suggesting a role in the complex mechanisms involved with the genesis of the motor and non-motor symptoms. Our study thus significantly contributes to the knowledge of the extrastriatal nondopaminergic mechanisms of PD with direct relevance to treatment of this disorder. PMID:23038412

  10. Cognitive-motor interactions of the basal ganglia in development

    PubMed Central

    Leisman, Gerry; Braun-Benjamin, Orit; Melillo, Robert

    2014-01-01

    Neural circuits linking activity in anatomically segregated populations of neurons in subcortical structures and the neocortex throughout the human brain regulate complex behaviors such as walking, talking, language comprehension, and other cognitive functions associated with frontal lobes. The basal ganglia, which regulate motor control, are also crucial elements in the circuits that confer human reasoning and adaptive function. The basal ganglia are key elements in the control of reward-based learning, sequencing, discrete elements that constitute a complete motor act, and cognitive function. Imaging studies of intact human subjects and electrophysiologic and tracer studies of the brains and behavior of other species confirm these findings. We know that the relation between the basal ganglia and the cerebral cortical region allows for connections organized into discrete circuits. Rather than serving as a means for widespread cortical areas to gain access to the motor system, these loops reciprocally interconnect a large and diverse set of cerebral cortical areas with the basal ganglia. Neuronal activity within the basal ganglia associated with motor areas of the cerebral cortex is highly correlated with parameters of movement. Neuronal activity within the basal ganglia and cerebellar loops associated with the prefrontal cortex is related to the aspects of cognitive function. Thus, individual loops appear to be involved in distinct behavioral functions. Damage to the basal ganglia of circuits with motor areas of the cortex leads to motor symptoms, whereas damage to the subcortical components of circuits with non-motor areas of the cortex causes higher-order deficits. In this report, we review some of the anatomic, physiologic, and behavioral findings that have contributed to a reappraisal of function concerning the basal ganglia and cerebellar loops with the cerebral cortex and apply it in clinical applications to attention deficit/hyperactivity disorder (ADHD

  11. Recent Advances of Reluctance Torque Assisted Motors

    NASA Astrophysics Data System (ADS)

    Ohyama, Kazunobu

    The history of motor technology began with the discovery of electromagnetic induction by Faraday. Various kinds of motors were developed by the recent progress of the fundamental technology (magnetic structure, magnetic material, drive circuit, control method). Especially, motors using the reluctance torque have many advantages and some of them are used as high efficient motors. This paper overviews recent advances of reluctance torque assisted motors such as Switched Reluctance Motor (SRM), Synchronous Reluctance Motor (SynRM) and Interior Permanent Magnet Synchronous Motor (IPMSM).

  12. Submersible canned motor mixer pump

    DOEpatents

    Guardiani, R.F.; Pollick, R.D.

    1997-10-07

    A mixer pump is described used in a waste tank for mobilizing high-level radioactive liquid waste having a column assembly containing power cables, a motor housing with electric motor means which includes a stator can of a stator assembly and a rotor can of a rotor assembly, and an impeller assembly with an impeller connected to a shaft of the rotor assembly. The column assembly locates the motor housing with the electric motor means adjacent to the impeller which creates an hydraulic head, and which forces the liquid waste into the motor housing to cool the electric motor means and to lubricate radial and thrust bearing assemblies. Hard-on-hard bearing surfaces of the bearing assemblies and a ring assembly between the impeller and electric motor means act to grind down large particles in the liquid waste flow. These larger particles are received in slots in the static bearing members of the radial bearing assemblies. Only solid waste particles smaller than the clearances in the system can pass there through, thereby resisting damage to and the interruption of the operation of the mixer pump. 10 figs.

  13. Submersible canned motor mixer pump

    DOEpatents

    Guardiani, Richard F.; Pollick, Richard D.

    1997-01-01

    A mixer pump used in a waste tank for mobilizing high-level radioactive liquid waste having a column assembly containing power cables, a motor housing with electric motor means which includes a stator can of a stator assembly and a rotor can of a rotor assembly, and an impeller assembly with an impeller connected to a shaft of the rotor assembly. The column assembly locates the motor housing with the electric motor means adjacent to the impeller which creates an hydraulic head, and which forces the liquid waste into the motor housing to cool the electric motor means and to lubricate radial and thrust bearing assemblies. Hard-on-hard bearing surfaces of the bearing assemblies and a ring assembly between the impeller and electric motor means act to grind down large particles in the liquid waste flow. These larger particles are received in slots in the static bearing members of the radial bearing assemblies. Only solid waste particles smaller than the clearances in the system can pass therethrough, thereby resisting damage to and the interruption of the operation of the mixer pump.

  14. Submersible canned motor transfer pump

    DOEpatents

    Guardiani, Richard F.; Pollick, Richard D.; Nyilas, Charles P.; Denmeade, Timothy J.

    1997-01-01

    A transfer pump used in a waste tank for transferring high-level radioactive liquid waste from a waste tank and having a column assembly, a canned electric motor means, and an impeller assembly with an upper impeller and a lower impeller connected to a shaft of a rotor assembly. The column assembly locates a motor housing with the electric motor means adjacent to the impeller assembly which creates an hydraulic head, and which forces the liquid waste, into the motor housing to cool the electric motor means and to cool and/or lubricate the radial and thrust bearing assemblies. Hard-on-hard bearing surfaces of the bearing assemblies and a ring assembly between the upper impeller and electric motor means grind large particles in the liquid waste flow. Slots in the static bearing member of the radial bearing assemblies further grind down the solid waste particles so that only particles smaller than the clearances in the system can pass therethrough, thereby resisting damage to and the interruption of the operation of the transfer pump. The column assembly is modular so that sections can be easily assembled, disassembled and/or removed. A second embodiment employs a stator jacket which provides an alternate means for cooling the electric motor means and lubricating and/or cooling the bearing assemblies, and a third embodiment employs a variable level suction device which allows liquid waste to be drawn into the transfer pump from varying and discrete levels in the waste tank.

  15. Solid rocket motor witness test

    NASA Technical Reports Server (NTRS)

    Welch, Christopher S.

    1991-01-01

    The Solid Rocket Motor Witness Test was undertaken to examine the potential for using thermal infrared imagery as a tool for monitoring static tests of solid rocket motors. The project consisted of several parts: data acquisition, data analysis, and interpretation. For data acquisition, thermal infrared data were obtained of the DM-9 test of the Space Shuttle Solid Rocket Motor on December 23, 1987, at Thiokol, Inc. test facility near Brigham City, Utah. The data analysis portion consisted of processing the video tapes of the test to produce values of temperature at representative test points on the rocket motor surface as the motor cooled down following the test. Interpretation included formulation of a numerical model and evaluation of some of the conditions of the motor which could be extracted from the data. These parameters included estimates of the insulation remaining following the tests and the thickness of the charred layer of insulation at the end of the test. Also visible was a temperature signature of the star grain pattern in the forward motor segment.

  16. Haptics in teaching handwriting: the role of perceptual and visuo-motor skills.

    PubMed

    Bara, Florence; Gentaz, Edouard

    2011-08-01

    Two studies were carried out in order to better understand the role of perceptual and visuo-motor skills in handwriting. Two training programs, visual-haptic (VH) and visual (V), were compared which differed in the way children explored the letters. The results revealed that improvements of VH training on letter recognition and handwriting quality were higher than improvements after V training. We suppose that VH training was more efficient because it improved both perceptual and visuo-motor skills. In the second experiment, in order to investigate the part of each component, we assessed the link between visuo-motor skills, perceptual skills and handwriting. The results showed that only the visuo-motor tasks predict handwriting copying performance. These results are discussed in relation to the respective roles of the perceptual and visuo-motor skills on letter shape learning and handwriting movement execution. PMID:21272948

  17. Terminal decline in motor function.

    PubMed

    Wilson, Robert S; Segawa, Eisuke; Buchman, Aron S; Boyle, Patricia A; Hizel, Loren P; Bennett, David A

    2012-12-01

    The study aim was to test the hypothesis that motor function undergoes accelerated decline proximate to death. As part of a longitudinal clinical-pathologic study, 124 older Roman Catholic nuns, priests, and monks completed at least 7 annual clinical evaluations, died, and underwent brain autopsy and uniform neuropathologic examination. Each evaluation included administration of 11 motor tests and 19 cognitive tests from which global measures of motor and cognitive function were derived. The global motor measure (baseline M = 0.82, SD = 0.21) declined a mean 0.024 unit per year (95% confidence interval [CI]: -0.032, -0.016) until a mean of 2.46 years (95% CI: -2.870, -2.108) before death when rate of decline increased nearly fivefold to -0.117 unit per year (95% CI: -0.140, -0.097). The global cognitive measure (baseline M = 0.07, SD = 0.45) declined a mean of 0.027-unit per year (95% CI: -0.041, -0.014) until a mean of 2.76 years (95% CI: -3.157, -2.372) before death when rate of decline increased more than 13-fold to -0.371 unit per year (95% CI: -0.443, -0.306). Onset of terminal motor decline was highly correlated with onset of terminal cognitive decline (r = .94, 95% CI: 0.81, 0.99), but rates of motor and cognitive change were not strongly correlated (preterminal r = .20, 95% CI: -0.05, 0.38; terminal r = .34, 95% CI: 0.03, 0.62). Higher level of plaques and tangles was associated with earlier onset of terminal decline in motor function, but no pathologic measures were associated with rate of preterminal or terminal motor decline. The results demonstrate that motor and cognitive functions both undergo a period of accelerated decline in the last few years of life. PMID:22612603

  18. Motor and non-motor behaviour in experimental Huntington's disease.

    PubMed

    Zeef, Dagmar H; Vlamings, Rinske; Lim, Lee Wei; Tan, Sonny; Janssen, Marcus L F; Jahanshahi, Ali; Hoogland, Govert; Prickaerts, Jos; Steinbusch, Harry W M; Temel, Yasin

    2012-01-15

    In this study, we investigated motor and non-motor behaviour in the transgenic rat model of Huntington's disease (tgHD). In particular, we were interested in the development and changes of motor and non-motor features (anxiety, motivation and hedonia) of disease over time and their interactions. We found tgHD animals to be hyperkinetic in the open field test compared to their wild-type littermates at all ages tested, which was accompanied by reduced anxiety-like behaviour in the open field test and the elevated zero maze, but not in the home cage emergence test. No major changes were found in hedonia (sucrose intake test) and motivation for food (food intake test). Our data suggest that hyperkinetic features and reduced-anxiety in the tgHD rats are associated behaviours and are seen in the earlier stages of the disease. PMID:22001615

  19. State observer for synchronous motors

    DOEpatents

    Lang, Jeffrey H.

    1994-03-22

    A state observer driven by measurements of phase voltages and currents for estimating the angular orientation of a rotor of a synchronous motor such as a variable reluctance motor (VRM). Phase voltages and currents are detected and serve as inputs to a state observer. The state observer includes a mathematical model of the electromechanical operation of the synchronous motor. The characteristics of the state observer are selected so that the observer estimates converge to the actual rotor angular orientation and velocity, winding phase flux linkages or currents.

  20. Ultra-Compact Motor Controller

    NASA Technical Reports Server (NTRS)

    Townsend, William T.; Cromwell, Adam; Hauptman, Traveler; Pratt, Gill Andrews

    2012-01-01

    This invention is an electronically commutated brushless motor contro ller that incorporates Hall-array sensing in a small, 42-gram packag e that provides 4096 absolute counts per motor revolution position s ensing. The unit is the size of a miniature hockey puck, and is a 44 -pin male connector that provides many I/O channels, including CANbus , RS-232 communications, general-purpose analog and digital I/O (GPI O), analog and digital Hall inputs, DC power input (18-90 VDC, 0-l0 A), three-phase motor outputs, and a strain gauge amplifier.

  1. Hybrid deorbit motor design feasibility

    NASA Technical Reports Server (NTRS)

    Hastings, Joseph H.

    1993-01-01

    This paper addresses the feasibility of using a hybrid rocket motor to deorbit the large booster stage of the proposed NLS. A hybrid motor was of interest because it could utilize the residual low pressure Gox from the boosters main engine Lox tank. The resulting study determines that the concept would be feasible and should be given further consideration. Also, a preliminary design for a deorbit motor was proposed which would weigh much less than an equivalent hypergolic system. The hybrid deorbit concept and design has the potential of yielding a simpler cost effective system that could also be applicable to future launch systems with similar missions.

  2. Hybrid deorbit motor design feasibility

    NASA Astrophysics Data System (ADS)

    Hastings, Joseph H.

    1993-06-01

    This paper addresses the feasibility of using a hybrid rocket motor to deorbit the large booster stage of the proposed NLS. A hybrid motor was of interest because it could utilize the residual low pressure Gox from the boosters main engine Lox tank. The resulting study determines that the concept would be feasible and should be given further consideration. Also, a preliminary design for a deorbit motor was proposed which would weigh much less than an equivalent hypergolic system. The hybrid deorbit concept and design has the potential of yielding a simpler cost effective system that could also be applicable to future launch systems with similar missions.

  3. The Advanced Solid Rocket Motor

    NASA Technical Reports Server (NTRS)

    Mitchell, Royce E.

    1992-01-01

    The paper describes the Advanced Solid Rocket Motor (ASRM) that is being developed to replace, in 1997, the Redesigned Solid Rocket Motor which currently boosts the Space Shuttle. The ASRM will contain features to improve motor safety (fewer potential leak paths, improved seal materials, stronger case material, and fewer nozzle and case joints), an improved ignition system using through-bulkhead initiators, and highly reproducible manufacturing and inspection techniques with a large number of automated procedures. The ASRM will be able to deliver 12,000 lbs greater payloads to any given orbit of the Shuttle. There are also environmental improvements, realized by waste propellant recovery.

  4. 26. View, looking east, of motor house; the electric motor ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    26. View, looking east, of motor house; the electric motor and electric-powered winch are housed in section of building to the left. The U-bolt and concrete deadman which anchors the cable of the tramway is to the right. Photo by Jet Lowe, HAER, 1989. - Puget Sound Power & Light Company, White River Hydroelectric Project, 600 North River Avenue, Dieringer, Pierce County, WA

  5. Turn Motors Off When Not in Use - Motor Tip Sheet #10

    SciTech Connect

    2008-07-01

    Motors use no energy when turned off. Reducing motor operating time by just 10% usually saves more energy than replacing a standard efficiency motor with a NEMA Premium® efficiency motor. In fact, given that 97% of the life cycle cost of purchasing and operating a motor is energy-related, turning a motor off 10% of the time could reduce energy costs enough to purchase three new motors.

  6. 76 FR 12214 - Motor Carrier Safety Advisory Committee Public Meeting

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-03-04

    ... Federal Motor Carrier Safety Administration Motor Carrier Safety Advisory Committee Public Meeting AGENCY: Federal Motor Carrier Safety Administration, DOT. ACTION: Notice: Announcement of Motor Carrier Safety Advisory Committee meeting; request for comment. SUMMARY: The Federal Motor Carrier Safety...

  7. 75 FR 29384 - Motor Carrier Safety Advisory Committee Public Meeting

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-05-25

    ... Federal Motor Carrier Safety Administration Motor Carrier Safety Advisory Committee Public Meeting AGENCY: Federal Motor Carrier Safety Administration (FMCSA), DOT. ACTION: Notice of Motor Carrier Safety Advisory Committee meeting. SUMMARY: FMCSA announces that its Motor Carrier Safety Advisory Committee (MCSAC)...

  8. 75 FR 50797 - Motor Carrier Safety Advisory Committee Public Meeting

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-08-17

    ... Federal Motor Carrier Safety Administration Motor Carrier Safety Advisory Committee Public Meeting AGENCY: Federal Motor Carrier Safety Administration (FMCSA), DOT. ACTION: Notice of Motor Carrier Safety Advisory Committee Meeting. SUMMARY: FMCSA announces that its Motor Carrier Safety Advisory Committee (MCSAC)...

  9. 75 FR 72863 - Motor Carrier Safety Advisory Committee Public Meeting

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-11-26

    ... Federal Motor Carrier Safety Administration Motor Carrier Safety Advisory Committee Public Meeting AGENCY: Federal Motor Carrier Safety Administration, DOT. ACTION: Notice of Motor Carrier Safety Advisory Committee Meeting. SUMMARY: FMCSA announces that the Agency's Motor Carrier Safety Advisory Committee...

  10. Mechanical thermal motor

    NASA Technical Reports Server (NTRS)

    Hein, L. A.; Myers, W. N. (Inventor)

    1976-01-01

    An apparatus is described for converting thermal energy such as solar energy into mechanical motion for driving fluid pumps and similar equipment. The thermal motor comprises an inner concentric cylinder carried by a stationary core member. The core member has a cylindrical disc plate fixed adjacent to a lower portion and extending radially from it. An outer concentric cylinder rotatably carried on the disc plate defining a space between the inner and outer concentric cylinders. A spiral tubular member encircles the inner concentric cylinder and is contained within the space between the inner and outer cylinders. One portion is connected to the inner concentric cylinder and a second portion connected to the outer concentric cylinder. A heated fluid is conveyed through the tubular member and is periodically cooled causing the tubular member to expand and contract. This causes the outer concentric cylinder to reciprocally rotate on the base plate accordingly. The reciprocating motion of the outer concentric cylinder is then utilized to drive a pump member in a pump chamber.

  11. Magnetic bearing and motor

    NASA Technical Reports Server (NTRS)

    Studer, P. A. (Inventor)

    1983-01-01

    A magnetic bearing for passively suspending a rotatable element subjected to axial and radial thrust forces is disclosed. The magnetic bearing employs a taut wire stretched along the longitudinal axis of the bearing between opposed end pieces and an intermediate magnetic section. The intermediate section is segmented to provide oppositely directed magnetic flux paths between the end pieces and may include either an axially polarized magnets interposed between the segments. The end pieces, separated from the intermediate section by air gaps, control distribution of magnetic flux between the intermediate section segments. Coaxial alignment of the end pieces with the intermediate section minimizes magnetic reluctance in the flux paths endowing the bearing with self-centering characteristics when subjected to radial loads. In an alternative embodiment, pairs of oppositely wound armature coils are concentrically interposed between segments of the intermediate section in concentric arcs adjacent to radially polarized magnets to equip a magnetic bearing as a torsion drive motor. The magnetic suspension bearing disclosed provides long term reliability without maintenance with application to long term space missions such as the VISSR/VAS scanning mirror instrument in the GOES program.

  12. Plasma motor generator system

    NASA Technical Reports Server (NTRS)

    Hite, Gerald E.

    1987-01-01

    The significant potential advantages of a plasma motor generator system over conventional systems for the generation of electrical power and propulsion for spacecraft in low Earth orbits warrants its further investigation. The two main components of such a system are a long insulated wire and the plasma generating hollow cathodes needed to maintain electrical contact with the ionosphere. Results of preliminary theoretical and experimental investigations of this system are presented. The theoretical work involved the equilibrium configurations of the wire and the nature of small oscillation about these equilibrium positions. A particularly interesting result was that two different configurations are allowed when the current is above a critical value. Experimental investigations were made of the optimal starting and running conditions for the proposed, low current hollow cathodes. Although optimal ranges of temperature, argon pressure and discharge voltage were identified, start up became progressively more difficult. This supposed depletion or contamination of the emissive surface could be countered by the addition of new emissive material.

  13. Useful signals from motor cortex

    PubMed Central

    Schwartz, Andrew B

    2007-01-01

    Historically, the motor cortical function has been explained as a funnel to muscle activation. This invokes the idea that motor cortical neurons, or ‘upper motoneurons’, directly cause muscle contraction just like spinal motoneurons. Thus, the motor cortex and muscle activity are inextricably entwined like a puppet master and his marionette. Recently, this concept has been challenged by current experimentation showing that many behavioural aspects of action are represented in motor cortical activity. Although this activity may still be related to muscle activation, the relation between the two is likely to be indirect and complex, whereas the relation between cortical activity and kinematic parameters is simple and robust. These findings show how to extract useful signals that help explain the underlying process that generates behaviour and to harness these signals for potentially therapeutic applications. PMID:17255162

  14. Small Solid Rocket Motor Test

    NASA Video Gallery

    It was three-two-one to brilliant fire as NASA's Marshall Space Flight Center tested a small solid rocket motor designed to mimic NASA's Space Launch System booster. The Mar. 14 test provides a qui...

  15. Drill-motor holding fixture

    NASA Technical Reports Server (NTRS)

    Chartier, E. N.; Culp, L. N.

    1980-01-01

    Guide improves accuracy and reduces likelihood of bit breakage in drilling large work pieces. Drill motor is mounted on pipe that slides on furniture clamp. Drill is driven into work piece by turning furniture-clamp handle.

  16. Force generation by cellular motors.

    PubMed

    Wanka, Friedrich; Van Zoelen, Everardus J J

    2003-01-01

    Cell motility processes in non-muscle cells depend on the activity of motor proteins that bind to either microtubules or actin filaments. From presently available data it must be concluded that the driving force is generated by transient interaction of the respective motors with microtubules or actin filaments which then activates the binding and hydrolysis of ATP. This reaction results in an abrupt discharge of the motor molecule, the direction of which is determined by the spatial orientation of its binding to the helical and polar vehicle. The latter is thereby propelled in its length direction and simultaneously undergoes an axial rotation, while the expelled motor exerts an oppositely directed current in the surrounding fluid, comparable to jet propulsion. Force production, propulsion velocities and energy requirements known from in vitro studies comply with those derived from the theory. The theory opens new ways for the understanding of cellular activities such as particle transport, mitosis and morphodynamics. PMID:14668925

  17. Synthesising Topological Links

    PubMed Central

    Baas, Nils A.; Seeman, Nadrian C.; Stacey, Andrew

    2014-01-01

    We discuss the chemical synthesis of topological links, in particular higher order links which have the Brunnian property (namely that removal of any one component unlinks the entire system). Furthermore, we suggest how to obtain both two dimensional and three dimensional objects (surfaces and solids, respectively) which also have this Brunnian property. PMID:25678732

  18. Solid rocket motor internal insulation

    NASA Technical Reports Server (NTRS)

    Twichell, S. E. (Editor); Keller, R. B., Jr.

    1976-01-01

    Internal insulation in a solid rocket motor is defined as a layer of heat barrier material placed between the internal surface of the case propellant. The primary purpose is to prevent the case from reaching temperatures that endanger its structural integrity. Secondary functions of the insulation are listed and guidelines for avoiding critical problems in the development of internal insulation for rocket motors are presented.

  19. Direct drive field actuator motors

    DOEpatents

    Grahn, A.R.

    1998-03-10

    A positive-drive field actuator motor is described which includes a stator carrying at least one field actuator which changes in dimension responsive to application of an energy field, and at least one drive shoe movable by the dimensional changes of the field actuator to contact and move a rotor element with respect to the stator. Various embodiments of the motor are disclosed, and the rotor element may be moved linearly or arcuately. 62 figs.

  20. Segmented rail linear induction motor

    DOEpatents

    Cowan, Jr., Maynard; Marder, Barry M.

    1996-01-01

    A segmented rail linear induction motor has a segmented rail consisting of a plurality of nonferrous electrically conductive segments aligned along a guideway. The motor further includes a carriage including at least one pair of opposed coils fastened to the carriage for moving the carriage. A power source applies an electric current to the coils to induce currents in the conductive surfaces to repel the coils from adjacent edges of the conductive surfaces.

  1. Segmented rail linear induction motor

    DOEpatents

    Cowan, M. Jr.; Marder, B.M.

    1996-09-03

    A segmented rail linear induction motor has a segmented rail consisting of a plurality of nonferrous electrically conductive segments aligned along a guideway. The motor further includes a carriage including at least one pair of opposed coils fastened to the carriage for moving the carriage. A power source applies an electric current to the coils to induce currents in the conductive surfaces to repel the coils from adjacent edges of the conductive surfaces. 6 figs.

  2. Meissner-Effect Stepping Motor

    NASA Technical Reports Server (NTRS)

    Robertson, Glen A.

    1991-01-01

    Proposed stepping motor derives torque from diamagnetic repulsion produced by Meissner effect - exclusion of magnetic field from interior of superconductor. Design of motor takes advantage of silver-doped YB2Cu3O and other compounds superconductive at temperatures as high as that of liquid nitrogen. Skin of rotor cooled below its superconducting-transition temperature by liquid nitrogen. O-rings prevent leaks of liquid nitrogen from rotor. Weight, cost, and maintenance reduced.

  3. Motor Activity Improves Temporal Expectancy

    PubMed Central

    Fautrelle, Lilian; Mareschal, Denis; French, Robert; Addyman, Caspar; Thomas, Elizabeth

    2015-01-01

    Certain brain areas involved in interval timing are also important in motor activity. This raises the possibility that motor activity might influence interval timing. To test this hypothesis, we assessed interval timing in healthy adults following different types of training. The pre- and post-training tasks consisted of a button press in response to the presentation of a rhythmic visual stimulus. Alterations in temporal expectancy were evaluated by measuring response times. Training consisted of responding to the visual presentation of regularly appearing stimuli by either: (1) pointing with a whole-body movement, (2) pointing only with the arm, (3) imagining pointing with a whole-body movement, (4) simply watching the stimulus presentation, (5) pointing with a whole-body movement in response to a target that appeared at irregular intervals (6) reading a newspaper. Participants performing a motor activity in response to the regular target showed significant improvements in judgment times compared to individuals with no associated motor activity. Individuals who only imagined pointing with a whole-body movement also showed significant improvements. No improvements were observed in the group that trained with a motor response to an irregular stimulus, hence eliminating the explanation that the improved temporal expectations of the other motor training groups was purely due to an improved motor capacity to press the response button. All groups performed a secondary task equally well, hence indicating that our results could not simply be attributed to differences in attention between the groups. Our results show that motor activity, even when it does not play a causal or corrective role, can lead to improved interval timing judgments. PMID:25806813

  4. A soft and dexterous motor

    NASA Astrophysics Data System (ADS)

    Anderson, Iain A.; Tse, Tony Chun Hin; Inamura, Tokushu; O'Brien, Benjamin M.; McKay, Thomas; Gisby, Todd

    2011-03-01

    We present a soft, bearing-free artificial muscle motor that cannot only turn a shaft but also grip and reposition it through a flexible gear. The bearing-free operation provides a foundation for low complexity soft machines, with multiple degree-of-freedom actuation, that can act simultaneously as motors and manipulators. The mechanism also enables an artificial muscle controlled gear change. Future work will include self-sensing feedback for precision, multidegree-of-freedom operation.

  5. Direct drive field actuator motors

    DOEpatents

    Grahn, Allen R.

    1998-01-01

    A positive-drive field actuator motor including a stator carrying at least one field actuator which changes in dimension responsive to application of an energy field, and at least one drive shoe movable by the dimensional changes of the field actuator to contact and move a rotor element with respect to the stator. Various embodiments of the motor are disclosed, and the rotor element may be moved linearly or arcuately.

  6. 30 CFR 18.34 - Motors.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 30 Mineral Resources 1 2014-07-01 2014-07-01 false Motors. 18.34 Section 18.34 Mineral Resources... PRODUCTS ELECTRIC MOTOR-DRIVEN MINE EQUIPMENT AND ACCESSORIES Construction and Design Requirements § 18.34 Motors. Explosion-proof electric motor assemblies intended for use in approved equipment in...

  7. 30 CFR 18.34 - Motors.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 30 Mineral Resources 1 2013-07-01 2013-07-01 false Motors. 18.34 Section 18.34 Mineral Resources... PRODUCTS ELECTRIC MOTOR-DRIVEN MINE EQUIPMENT AND ACCESSORIES Construction and Design Requirements § 18.34 Motors. Explosion-proof electric motor assemblies intended for use in approved equipment in...

  8. 30 CFR 18.34 - Motors.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 30 Mineral Resources 1 2012-07-01 2012-07-01 false Motors. 18.34 Section 18.34 Mineral Resources... PRODUCTS ELECTRIC MOTOR-DRIVEN MINE EQUIPMENT AND ACCESSORIES Construction and Design Requirements § 18.34 Motors. Explosion-proof electric motor assemblies intended for use in approved equipment in...

  9. Electric motor for laser-mechanical drilling

    DOEpatents

    Grubb, Daryl L.; Faircloth, Brian O.; Zediker, Mark S.

    2015-07-07

    A high power laser drilling system utilizing an electric motor laser bottom hole assembly. A high power laser beam travels within the electric motor for advancing a borehole. High power laser drilling system includes a down hole electrical motor having a hollow rotor for conveying a high power laser beam through the electrical motor.

  10. The influence of Oxytocin on automatic motor simulation.

    PubMed

    De Coster, Lize; Mueller, Sven C; T'Sjoen, Guy; De Saedeleer, Lien; Brass, Marcel

    2014-12-01

    Motor simulation is important for imitation, action understanding, and a wide range of social cognitive skills. Furthermore, the neuropeptide hormone Oxytocin (OT) has also been related to social information processing in humans, improving perception of social stimuli and increasing altruism and trust. Surprisingly, however, a direct link between OT and motor simulation has never been systematically investigated. The current study examined this question using the imitation-inhibition task, a paradigm used to investigate automatic imitation behaviour and motor simulation. In this task, participants carry out simple finger movements while observing irrelevant movements that either match (congruent condition) or do not match (incongruent condition) the instructed movements. In a double-blind, placebo-controlled design, male participants were administered either OT (N=24) or placebo (N=24), and subsequently performed the imitation-inhibition task. To ensure specificity of OT effects to imitative behaviour, participants additionally performed a Stroop colour-word interference task (adapted to optimize similarities with the imitation inhibition task) to rule out general effects on cognitive control. As predicted, OT selectively influenced the congruency effect in the imitation-inhibition task but not the congruency effect in the Stroop task. This effect showed that OT led to a larger congruency effect by slowing down reaction times on incongruent trials when observed and own actions did not match. The findings suggest that OT leads to a decrease of control over automatic imitative behaviour mediated by increased self-other merging. Thus, for the first time, a link between OT and motor simulation is demonstrated, providing a window into the role of OT in motoric aspects of social cognition. PMID:25240207

  11. LTD, RP, and Motor Learning.

    PubMed

    Hirano, Tomoo; Yamazaki, Yoshito; Nakamura, Yoji

    2016-02-01

    Long-term depression (LTD) at excitatory synapses between parallel fibers and a Purkinje cell has been regarded as a critical cellular mechanism for motor learning. However, it was demonstrated that normal motor learning occurs under LTD suppression, suggesting that cerebellar plasticity mechanisms other than LTD also contribute to motor learning. One candidate for such plasticity is rebound potentiation (RP), which is long-term potentiation at inhibitory synapses between a stellate cell and a Purkinje cell. Both LTD and RP are induced by the increase in postsynaptic Ca(2+) concentration, and work to suppress the activity of a Purkinje cell. Thus, LTD and RP might work synergistically, and one might compensate defects of the other. RP induction is dependent on the interaction between GABAA receptor and GABAA receptor binding protein (GABARAP). Transgenic mice expressing a peptide which inhibits binding of GABARAP and GABAA receptor only in Purkinje cells show defects in both RP and adaptation of vestibulo-ocular reflex (VOR), a motor learning paradigm. However, another example of motor learning, adaptation of optokinetic response (OKR), is normal in the transgenic mice. Both VOR and OKR are reflex eye movements suppressing the slip of visual image on the retina during head movement. Previously, we reported that delphilin knockout mice show facilitated LTD induction and enhanced OKR adaptation, but we recently found that VOR adaptation was not enhanced in the knockout mice. These results together suggest that animals might use LTD and RP differently depending on motor learning tasks. PMID:26160222

  12. Precision stop control for motors

    NASA Technical Reports Server (NTRS)

    Howard, David E. (Inventor); Montenegro, Justino (Inventor)

    2000-01-01

    An improved stop control system and method are provided for a motor having a drive mechanism in which the motor is coupled to a motor controller that controls the speed and position of the drive mechanism using a first signal indicative of a commanded position of the drive mechanism, a second signal indicative of the actual speed of the drive mechanism and a third signal indicative of the actual position of the drive mechanism. The improved system/method uses a first circuit that receives the first and third signal and generates an error signal indicative of a difference therebetween. A second circuit receives the error signal and compares same with a threshold position error. The result of this comparison is used to selectively supply the second signal (i.e., speed) to the motor controller at least whenever the error signal is less than the threshold position error so that the motor controller can use the second signal in conjunction with the third signal to stop the motor.

  13. Motor mapping in cerebral palsy.

    PubMed

    Wittenberg, George F

    2009-10-01

    The measurement of motor deficits in individuals with cerebral palsy (CP) has been largely based on clinical criteria. Yet functional imaging and non-invasive stimulation methods provide a means to measure directly abnormalities of the motor system. The size and location of muscles and movement representations can be determined with transcranial magnetic stimulation (TMS) and functional magnetics resonance imaging. Thus the homunculus can be individually mapped in children with CP. Because size of representation within the homunculus relates to quality of motor control, measurement of the distance between body parts provides a metric that may be useful in classifying deficits. Bilateral motor control in one hemisphere, while normal in neonates, persists variably in CP, providing another physiological metric. In this study, we used TMS to measure hand and ankle representations in a convenience sample of children with spastic CP. Overlapping thumb and ankle maps were found in children with both hemiplegia and diplegia, and these maps may be from either side of the body. While more participants are required to make conclusions about disability and compression/bilaterality of the homunculus, it appears as if TMS-derived metrics relate to motor abnormalities. These abnormal motor maps also are a therapeutic target, as stimulation methods are being developed as adjuncts to physical means of rehabilitation. PMID:19740221

  14. Optical Communications Link to Airborne Transceiver

    NASA Technical Reports Server (NTRS)

    Regehr, Martin W.; Kovalik, Joseph M.; Biswas, Abhijit

    2011-01-01

    An optical link from Earth to an aircraft demonstrates the ability to establish a link from a ground platform to a transceiver moving overhead. An airplane has a challenging disturbance environment including airframe vibrations and occasional abrupt changes in attitude during flight. These disturbances make it difficult to maintain pointing lock in an optical transceiver in an airplane. Acquisition can also be challenging. In the case of the aircraft link, the ground station initially has no precise knowledge of the aircraft s location. An airborne pointing system has been designed, built, and demonstrated using direct-drive brushless DC motors for passive isolation of pointing disturbances and for high-bandwidth control feedback. The airborne transceiver uses a GPS-INS system to determine the aircraft s position and attitude, and to then illuminate the ground station initially for acquisition. The ground transceiver participates in link-pointing acquisition by first using a wide-field camera to detect initial illumination from the airborne beacon, and to perform coarse pointing. It then transfers control to a high-precision pointing detector. Using this scheme, live video was successfully streamed from the ground to the aircraft at 270 Mb/s while simultaneously downlinking a 50 kb/s data stream from the aircraft to the ground.

  15. Intraoperative monitoring of motor function by magnetic motor evoked potentials.

    PubMed

    Lee, W Y; Hou, W Y; Yang, L H; Lin, S M

    1995-03-01

    Under etomidate anesthesia, motor evoked potentials produced by magnetic stimulation were successfully recorded from 10 thenar muscles and 10 anterior tibial muscles of eight patients who had undergone surgery on the medulla oblongata and the cervical and thoracic spinal cords. Recordings taken before placing the neural tissue at risk were assessed for variability in amplitude and latency. The lower limit in amplitude was approximately one-third (25-43%) of the baseline. The latencies were more difficult to monitor than were the amplitudes. The latency variations were 2.56 +/- 0.50 milliseconds for the hand and 6.84 +/- 1.37 milliseconds for the leg. During surgery, the unilateral recordings of two patients were transiently lost but partially recovered after a pause in the operation. No obvious postoperative weaknesses in the corresponding limbs occurred. One patient, who showed a permanent loss of unilateral recording, had transient monoplegia with a complete recovery. None of the remaining five patients who had amplitudes larger than one-third of the baseline at the end of the operation had additional motor deficits. Our conclusions are that under etomidate anesthesia, the magnetic motor evoked potentials can be convenient and reliable monitors of motor function, that changes in the amplitude may be superior to those in the latency for intraoperative warning, that the criterion for potential neural damage under magnetic motor evoked potential monitoring might be an amplitude reduction of two-thirds of the control value, and that the magnetic stimulation seems to be more sensitive than the electrical stimulation in the monitoring of motor function and also allows more time and opportunities for the motor function to recover. PMID:7753349

  16. The Infant Motor Profile: A Standardized and Qualitative Method to Assess Motor Behaviour in Infancy

    ERIC Educational Resources Information Center

    Heineman, Kirsten R.; Bos, Arend F.; Hadders-Algra, Mijna

    2008-01-01

    A reliable and valid instrument to assess neuromotor condition in infancy is a prerequisite for early detection of developmental motor disorders. We developed a video-based assessment of motor behaviour, the Infant Motor Profile (IMP), to evaluate motor abilities, movement variability, ability to select motor strategies, movement symmetry, and…

  17. 41 CFR 102-34.85 - What motor vehicles require motor vehicle identification?

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 41 Public Contracts and Property Management 3 2014-01-01 2014-01-01 false What motor vehicles require motor vehicle identification? 102-34.85 Section 102-34.85 Public Contracts and Property Management... 34-MOTOR VEHICLE MANAGEMENT Identifying and Registering Motor Vehicles Motor Vehicle...

  18. 41 CFR 102-34.85 - What motor vehicles require motor vehicle identification?

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 41 Public Contracts and Property Management 3 2012-01-01 2012-01-01 false What motor vehicles require motor vehicle identification? 102-34.85 Section 102-34.85 Public Contracts and Property Management... 34-MOTOR VEHICLE MANAGEMENT Identifying and Registering Motor Vehicles Motor Vehicle...

  19. Motoric cognitive risk syndrome

    PubMed Central

    Annweiler, Cedric; Ayers, Emmeline; Barzilai, Nir; Beauchet, Olivier; Bennett, David A.; Bridenbaugh, Stephanie A.; Buchman, Aron S.; Callisaya, Michele L.; Camicioli, Richard; Capistrant, Benjamin; Chatterji, Somnath; De Cock, Anne-Marie; Ferrucci, Luigi; Giladi, Nir; Guralnik, Jack M.; Hausdorff, Jeffrey M.; Holtzer, Roee; Kim, Ki Woong; Kowal, Paul; Kressig, Reto W.; Lim, Jae-Young; Lord, Susan; Meguro, Kenichi; Montero-Odasso, Manuel; Muir-Hunter, Susan W.; Noone, Mohan L.; Rochester, Lynn; Srikanth, Velandai; Wang, Cuiling

    2014-01-01

    Objectives: Our objective is to report prevalence of motoric cognitive risk syndrome (MCR), a newly described predementia syndrome characterized by slow gait and cognitive complaints, in multiple countries, and its association with dementia risk. Methods: Pooled MCR prevalence analysis of individual data from 26,802 adults without dementia and disability aged 60 years and older from 22 cohorts from 17 countries. We also examined risk of incident cognitive impairment (Mini-Mental State Examination decline ≥4 points) and dementia associated with MCR in 4,812 individuals without dementia with baseline Mini-Mental State Examination scores ≥25 from 4 prospective cohort studies using Cox models adjusted for potential confounders. Results: At baseline, 2,808 of the 26,802 participants met MCR criteria. Pooled MCR prevalence was 9.7% (95% confidence interval [CI] 8.2%–11.2%). MCR prevalence was higher with older age but there were no sex differences. MCR predicted risk of developing incident cognitive impairment in the pooled sample (adjusted hazard ratio [aHR] 2.0, 95% CI 1.7–2.4); aHRs were 1.5 to 2.7 in the individual cohorts. MCR also predicted dementia in the pooled sample (aHR 1.9, 95% CI 1.5–2.3). The results persisted even after excluding participants with possible cognitive impairment, accounting for early dementia, and diagnostic overlap with other predementia syndromes. Conclusion: MCR is common in older adults, and is a strong and early risk factor for cognitive decline. This clinical approach can be easily applied to identify high-risk seniors in a wide variety of settings. PMID:25031288

  20. Space shuttle booster separation motor design

    NASA Technical Reports Server (NTRS)

    Smith, G. W.; Chase, C. A.

    1976-01-01

    The separation characteristics of the space shuttle solid rocket boosters (SRBs) are introduced along with the system level requirements for the booster separation motors (BSMs). These system requirements are then translated into specific motor requirements that control the design of the BSM. Each motor component is discussed including its geometry, material selection, and fabrication process. Also discussed is the propellant selection, grain design, and performance capabilities of the motor. The upcoming test program to develop and qualify the motor is outlined.

  1. At the interface of sensory and motor dysfunctions and Alzheimer’s Disease

    PubMed Central

    Albers, Mark W.; Gilmore, Grover C.; Kaye, Jeffrey; Murphy, Claire; Wingfield, Arthur; Bennett, David A.; Boxer, Adam L.; Buchman, Aron S.; Cruickshanks, Karen J.; Devanand, Davangere P.; Duffy, Charles J.; Gall, Christine M.; Gates, George A.; Granholm, Ann-Charlotte; Hensch, Takao; Holtzer, Roee; Hyman, Bradley T.; Lin, Frank R.; McKee, Ann C.; Morris, John C.; Petersen, Ronald C.; Silbert, Lisa C.; Struble, Robert G.; Trojanowski, John Q.; Verghese, Joe; Wilson, Donald A.; Xu, Shunbin; Zhang, Li I.

    2014-01-01

    Recent evidence indicates that sensory and motor changes may precede the cognitive symptoms of Alzheimer’s disease (AD) by several years and may signify increased risk of developing AD. Traditionally, sensory and motor dysfunctions in aging and AD have been studied separately. To ascertain the evidence supporting the relationship between age-related changes in sensory and motor systems and the development of AD and to facilitate communication between several disciplines, the National Institute on Aging held an exploratory workshop titled “Sensory and Motor Dysfunctions in Aging and Alzheimer’s Disease”. The scientific sessions of the workshop focused on age-related and neuropathological changes in the olfactory, visual, auditory, and motor systems, followed by extensive discussion and hypothesis generation related to the possible links among sensory, cognitive, and motor domains in aging and AD. Based on the data presented and discussed at this workshop, it is clear that sensory and motor regions of the CNS are affected by Alzheimer pathology and that interventions targeting amelioration of sensory-motor deficits in AD may enhance patient function as AD progresses. PMID:25022540

  2. A network for audio-motor coordination in skilled pianists and non-musicians.

    PubMed

    Baumann, Simon; Koeneke, Susan; Schmidt, Conny F; Meyer, Martin; Lutz, Kai; Jancke, Lutz

    2007-08-01

    Playing a musical instrument requires efficient auditory and motor processing. Fast feed forward and feedback connections that link the acoustic target to the corresponding motor programs need to be established during years of practice. The aim of our study is to provide a detailed description of cortical structures that participate in this audio-motor coordination network in professional pianists and non-musicians. In order to map these interacting areas using functional magnetic resonance imaging (fMRI), we considered cortical areas that are concurrently activated during silent piano performance and motionless listening to piano sound. Furthermore we investigated to what extent interactions between the auditory and the motor modality happen involuntarily. We observed a network of predominantly secondary and higher order areas belonging to the auditory and motor modality. The extent of activity was clearly increased by imagination of the absent modality. However, this network did neither comprise primary auditory nor primary motor areas in any condition. Activity in the lateral dorsal premotor cortex (PMd) and the pre-supplementary motor cortex (preSMA) was significantly increased for pianists. Our data imply an intermodal transformation network of auditory and motor areas which is subject to a certain degree of plasticity by means of intensive training. PMID:17603027

  3. An action-incongruent secondary task modulates prediction accuracy in experienced performers: evidence for motor simulation.

    PubMed

    Mulligan, Desmond; Lohse, Keith R; Hodges, Nicola J

    2016-07-01

    We provide behavioral evidence that the human motor system is involved in the perceptual decision processes of skilled performers, directly linking prediction accuracy to the (in)ability of the motor system to activate in a response-specific way. Experienced and non-experienced dart players were asked to predict, from temporally occluded video sequences, the landing position of a dart thrown previously by themselves (self) or another (other). This prediction task was performed while additionally performing (a) an action-incongruent secondary motor task (right arm force production), (b) a congruent secondary motor task (mimicking) or (c) an attention-matched task (tone-monitoring). Non-experienced dart players were not affected by any of the secondary task manipulations, relative to control conditions, yet prediction accuracy decreased for the experienced players when additionally performing the force-production, motor task. This interference effect was present for 'self' as well as 'other' decisions, reducing the accuracy of experienced participants to a novice level. The mimicking (congruent) secondary task condition did not interfere with (or facilitate) prediction accuracy for either group. We conclude that visual-motor experience moderates the process of decision making, such that a seemingly visual-cognitive prediction task relies on activation of the motor system for experienced performers. This fits with a motor simulation account of action prediction in sports and other tasks, and alerts to the specificity of these simulative processes. PMID:26021748

  4. At the interface of sensory and motor dysfunctions and Alzheimer's disease.

    PubMed

    Albers, Mark W; Gilmore, Grover C; Kaye, Jeffrey; Murphy, Claire; Wingfield, Arthur; Bennett, David A; Boxer, Adam L; Buchman, Aron S; Cruickshanks, Karen J; Devanand, Davangere P; Duffy, Charles J; Gall, Christine M; Gates, George A; Granholm, Ann-Charlotte; Hensch, Takao; Holtzer, Roee; Hyman, Bradley T; Lin, Frank R; McKee, Ann C; Morris, John C; Petersen, Ronald C; Silbert, Lisa C; Struble, Robert G; Trojanowski, John Q; Verghese, Joe; Wilson, Donald A; Xu, Shunbin; Zhang, Li I

    2015-01-01

    Recent evidence indicates that sensory and motor changes may precede the cognitive symptoms of Alzheimer's disease (AD) by several years and may signify increased risk of developing AD. Traditionally, sensory and motor dysfunctions in aging and AD have been studied separately. To ascertain the evidence supporting the relationship between age-related changes in sensory and motor systems and the development of AD and to facilitate communication between several disciplines, the National Institute on Aging held an exploratory workshop titled "Sensory and Motor Dysfunctions in Aging and AD." The scientific sessions of the workshop focused on age-related and neuropathologic changes in the olfactory, visual, auditory, and motor systems, followed by extensive discussion and hypothesis generation related to the possible links among sensory, cognitive, and motor domains in aging and AD. Based on the data presented and discussed at this workshop, it is clear that sensory and motor regions of the central nervous system are affected by AD pathology and that interventions targeting amelioration of sensory-motor deficits in AD may enhance patient function as AD progresses. PMID:25022540

  5. TRP's: links to schizophrenia?

    PubMed

    Chahl, Loris A

    2007-08-01

    Schizophrenia is a chronic psychiatric disorder the cause of which is unknown. It is considered to be a neurodevelopmental disorder that results from an interaction of genetic and environmental factors. Direct evidence for links between schizophrenia and TRP channels is lacking. However, several aspects of the pathophysiology of the disorder point to a possible involvement of TRP channels. In this review evidence for links between TRP channels and schizophrenia with respect to neurodevelopment, dopaminergic and cannabinoid systems, thermoregulation, and sensory processes, is discussed. Investigation of these links holds the prospect of a new understanding of schizophrenia with resultant therapeutic advances. PMID:17587552

  6. Fiber optic communication links

    SciTech Connect

    Meyer, R. H.

    1980-01-01

    Fiber optics is a new, emerging technology which offers relief from many of the problems which limited past communications links. Its inherent noise immunity and high bandwidth open the door for new designs with greater capabilities. Being a new technology, certain problems can be encountered in specifying and installing a fiber optic link. A general fiber optic system is discussed with emphasis on the advantages and disadvantages. It is not intended to be technical in nature, but a general discussion. Finally, a general purpose prototype Sandia communications link is presented.

  7. The moving phantom: motor execution or motor imagery?

    PubMed

    Raffin, Estelle; Giraux, Pascal; Reilly, Karen T

    2012-06-01

    Amputees who have a phantom limb often report the ability to move this phantom voluntarily. In the literature, phantom limb movements are generally considered to reflect motor imagery rather than motor execution. The aim of this study was to investigate whether amputees distinguish between executing a movement of the phantom limb and imagining moving the missing limb. We examined the capacity of 19 upper-limb amputees to execute and imagine movements of both their phantom and intact limbs. Their behaviour was compared with that of 18 age-matched normal controls. A global questionnaire-based assessment of imagery ability and timed tests showed that amputees can indeed distinguish between motor execution and motor imagery with the phantom limb, and that the former is associated with activity in stump muscles while the latter is not. Amputation reduced the speed of voluntary movements with the phantom limb but did not change the speed of imagined movements, suggesting that the absence of the limb specifically affects the ability to voluntarily move the phantom but does not change the ability to imagine moving the missing limb. These results suggest that under some conditions, for example amputation, the predicted sensory consequences of a motor command are sufficient to evoke the sensation of voluntary movement. They also suggest that the distinction between imagined and executed movements should be taken into consideration when designing research protocols to investigate the analgesic effects of sensorimotor feedback. PMID:21397901

  8. The Effect of Teachers Trained in a Fundamental Movement Skills Programme on Children's Self-Perceptions and Motor Competence

    ERIC Educational Resources Information Center

    Breslin, Gavin; Murphy, Marie; McKee, David; Delaney, Brian; Dempster, Martin

    2012-01-01

    Perceived and actual motor competence are hypothesized to have potential links to children and young people's physical activity (PA) levels with a potential consequential link to long-term health. In this cross-sectional study, Harter's (1985, "Manual for the Self-perception Profile for Children." Denver, CO: University of Denver) Competency…

  9. Lower Motor Neuron Findings after Upper Motor Neuron Injury: Insights from Postoperative Supplementary Motor Area Syndrome

    PubMed Central

    Florman, Jeffrey E.; Duffau, Hugues; Rughani, Anand I.

    2013-01-01

    Hypertonia and hyperreflexia are classically described responses to upper motor neuron injury. However, acute hypotonia and areflexia with motor deficit are hallmark findings after many central nervous system insults such as acute stroke and spinal shock. Historic theories to explain these contradictory findings have implicated a number of potential mechanisms mostly relying on the loss of descending corticospinal input as the underlying etiology. Unfortunately, these simple descriptions consistently fail to adequately explain the pathophysiology and connectivity leading to acute hyporeflexia and delayed hyperreflexia that result from such insult. This article highlights the common observation of acute hyporeflexia after central nervous system insults and explores the underlying anatomy and physiology. Further, evidence for the underlying connectivity is presented and implicates the dominant role of supraspinal inhibitory influence originating in the supplementary motor area descending through the corticospinal tracts. Unlike traditional explanations, this theory more adequately explains the findings of postoperative supplementary motor area syndrome in which hyporeflexia motor deficit is observed acutely in the face of intact primary motor cortex connections to the spinal cord. Further, the proposed connectivity can be generalized to help explain other insults including stroke, atonic seizures, and spinal shock. PMID:23508473

  10. Submersible canned motor transfer pump

    DOEpatents

    Guardiani, R.F.; Pollick, R.D.; Nyilas, C.P.; Denmeade, T.J.

    1997-08-19

    A transfer pump is described which is used in a waste tank for transferring high-level radioactive liquid waste from a waste tank and having a column assembly, a canned electric motor means, and an impeller assembly with an upper impeller and a lower impeller connected to a shaft of a rotor assembly. The column assembly locates a motor housing with the electric motor means adjacent to the impeller assembly which creates an hydraulic head, and which forces the liquid waste, into the motor housing to cool the electric motor means and to cool and/or lubricate the radial and thrust bearing assemblies. Hard-on-hard bearing surfaces of the bearing assemblies and a ring assembly between the upper impeller and electric motor means grind large particles in the liquid waste flow. Slots in the static bearing member of the radial bearing assemblies further grind down the solid waste particles so that only particles smaller than the clearances in the system can pass there through, thereby resisting damage to and the interruption of the operation of the transfer pump. The column assembly is modular so that sections can be easily assembled, disassembled and/or removed. A second embodiment employs a stator jacket which provides an alternate means for cooling the electric motor means and lubricating and/or cooling the bearing assemblies, and a third embodiment employs a variable level suction device which allows liquid waste to be drawn into the transfer pump from varying and discrete levels in the waste tank. 17 figs.

  11. Corneal cross-linking.

    PubMed

    Randleman, J Bradley; Khandelwal, Sumitra S; Hafezi, Farhad

    2015-01-01

    Since its inception in the late 1990s, corneal cross-linking has grown from an interesting concept to a primary treatment for corneal ectatic disease worldwide. Using a combination of ultraviolet-A light and a chromophore (vitamin B2, riboflavin), the cornea can be stiffened, usually with a single application, and progressive thinning diseases such as keratoconus arrested. Despite being in clinical use for many years, some of the underlying processes, such as the role of oxygen and the optimal treatment times, are still being worked out. More than a treatment technique, corneal cross-links represent a physiological principle of connective tissue, which may explain the enormous versatility of the method. We highlight the history of corneal cross-linking, the scientific underpinnings of current techniques, evolving clinical treatment parameters, and the use of cross-linking in combination with refractive surgery and for the treatment of infectious keratitis. PMID:25980780

  12. CERES Web Links

    Atmospheric Science Data Center

    2013-03-21

    ...   Web Links to Relevant CERES Information Relevant information about CERES, CERES references, ... Instrument Working Group Home Page Aerosol Retrieval Web Page  (Center for Satellite Applications and Research) ...

  13. Latest Research: Genetic Links

    MedlinePlus

    ... Current Issue Past Issues Feature: Vision Latest Research: Genetic Links Past Issues / Summer 2008 Table of Contents ... laboratories is one way the NEI is expanding genetic testing of eye diseases. Photo courtesy of National ...

  14. Updating the research domain criteria: the utility of a motor dimension.

    PubMed

    Bernard, J A; Mittal, V A

    2015-10-01

    Within the NIMH Research Domain Criteria (RDoC) framework, dimensions of behavior are investigated across diagnoses with the goal of developing a better understanding of their underlying neural substrates. Currently, this framework includes five domains: cognitive, social, arousal/regulatory, negative, and positive valence systems. We argue that the inclusion of a motor systems domain is sorely needed as well. Independent of medication, distinct areas of motor dysfunction (e.g. motor planning/inhibition/learning/coordination, involuntary movements) commonly appear across a number of mental disorders (e.g. schizophrenia, bipolar disorder, autism, attention deficit hyperactivity disorder, Alzheimer's disease, depression) as well as neurological disorders accompanied by significant psychological symptoms (e.g. Parkinson's disease). In addition, motor systems are amenable to study across multiple levels of analysis from the cellular molecular level focusing on cytoarchitechtonics and neurotransmitter systems, to networks and circuits measured using neuroimaging, and finally at the level of overt behavioral performance. Critically, the neural systems associated with motor performance have been relatively well defined, and different circuits have been linked to distinct aspects of motor behavior. As such, they may also be differentially associated with symptoms and motor dysfunction across diagnoses, and be uniquely informative about underlying etiology. Importantly, motor signs can change across stages of illness; they are also often present in the prodromal phases of disease and closely linked with course, suggesting that these behaviors represent a core feature reflective of pathogenic processes. The inclusion of a motor domain would allow researchers to better understand psychopathology more broadly, and may also reveal important contributions to disease processes across diagnoses. PMID:26005109

  15. Improve Motor Operation at Off-Design Voltages - Motor Tip Sheet #9

    SciTech Connect

    2008-07-01

    Motors are designed to operate within +/- 10% of their nameplate rated voltages. When motors operate at conditions of over- or under-voltage, motor efficiency and other performance parameters are degraded.

  16. Excitability of hand motor areas during articulation of syllables.

    PubMed

    Komeilipoor, Naeem; Tiainen, Mikko; Tiippana, Kaisa; Vainio, Martti; Vainio, Lari

    2016-05-01

    It is known that articulating different syllables is linked to different grasp actions, e.g. [ti] is linked to precision grip, and [kɑ] to power grip. The aim of the present study was to test whether articulating or hearing these syllables would result in an increased activity in the representation of hand muscles involved in these two actions in a muscle-specific manner. To this end, we used transcranial magnetic stimulation (TMS) to investigate changes in the excitability of the left primary motor cortex (M1) innervating hand muscles while participants articulated or listened to meaningless syllables, listened to a metronome, or observed a fixation cross. The motor-evoked potentials of two hand muscles associated with either a precision or power grip exhibited significantly greater amplitudes during articulation than in passive listening, metronome, and fixation cross conditions. Moreover, these muscles exhibited similar patterns of excitability during articulation regardless of which syllable was articulated. The increased excitability of the left M1 hand area during articulation, but not during perception of the syllables, might be due to the cortico-cortical interaction between the motor representations of oral organs with the hand area. PMID:27057730

  17. Subcortical evoked activity and motor enhancement in Parkinson's disease

    PubMed Central

    Anzak, Anam; Tan, Huiling; Pogosyan, Alek; Khan, Sadaquate; Javed, Shazia; Gill, Steven S.; Ashkan, Keyoumars; Akram, Harith; Foltynie, Thomas; Limousin, Patricia; Zrinzo, Ludvic; Green, Alexander L.; Aziz, Tipu; Brown, Peter

    2016-01-01

    Enhancements in motor performance have been demonstrated in response to intense stimuli both in healthy subjects and in the form of ‘paradoxical kinesis’ in patients with Parkinson's disease. Here we identify a mid-latency evoked potential in local field potential recordings from the region of the subthalamic nucleus, which scales in amplitude with both the intensity of the stimulus delivered and corresponding enhancements in biomechanical measures of maximal handgrips, independent of the dopaminergic state of our subjects with Parkinson's disease. Recordings of a similar evoked potential in the related pedunculopontine nucleus – a key component of the reticular activating system – provide support for this neural signature in the subthalmic nucleus being a novel correlate of ascending arousal, propagated from the reticular activating system to exert an ‘energizing’ influence on motor circuitry. Future manipulation of this system linking arousal and motor performance may provide a novel approach for the non-dopaminergic enhancement of motor performance in patients with hypokinetic disorders such as Parkinson's disease. PMID:26687971

  18. Subcortical evoked activity and motor enhancement in Parkinson's disease.

    PubMed

    Anzak, Anam; Tan, Huiling; Pogosyan, Alek; Khan, Sadaquate; Javed, Shazia; Gill, Steven S; Ashkan, Keyoumars; Akram, Harith; Foltynie, Thomas; Limousin, Patricia; Zrinzo, Ludvic; Green, Alexander L; Aziz, Tipu; Brown, Peter

    2016-03-01

    Enhancements in motor performance have been demonstrated in response to intense stimuli both in healthy subjects and in the form of 'paradoxical kinesis' in patients with Parkinson's disease. Here we identify a mid-latency evoked potential in local field potential recordings from the region of the subthalamic nucleus, which scales in amplitude with both the intensity of the stimulus delivered and corresponding enhancements in biomechanical measures of maximal handgrips, independent of the dopaminergic state of our subjects with Parkinson's disease. Recordings of a similar evoked potential in the related pedunculopontine nucleus - a key component of the reticular activating system - provide support for this neural signature in the subthalmic nucleus being a novel correlate of ascending arousal, propagated from the reticular activating system to exert an 'energizing' influence on motor circuitry. Future manipulation of this system linking arousal and motor performance may provide a novel approach for the non-dopaminergic enhancement of motor performance in patients with hypokinetic disorders such as Parkinson's disease. PMID:26687971

  19. Somatosensory feedback modulates the respiratory motor program of crystallized birdsong

    PubMed Central

    Suthers, Roderick A.; Goller, Franz; Wild, J. Martin

    2002-01-01

    Birdsong, like human speech, involves rapid, repetitive, or episodic motor patterns requiring precise coordination between respiratory, vocal organ, and vocal tract muscles. The song units or syllables of most adult songbirds exhibit a high degree of acoustic stereotypy that persists for days or months after the elimination of auditory feedback by deafening. Adult song is assumed to depend on central motor programs operating independently from immediate sensory feedback. Nothing is known, however, about the possible role of mechanoreceptive or other somatosensory feedback in the motor control of birdsong. Even in the case of human speech, the question of “how and when sensory information is used in normal speaking conditions… remains unanswered” and controversial [Smith, A. (1992) Crit. Rev. Oral Biol. Med. 3, 233–267]. We report here evidence for somatosensory modulation of ongoing song motor patterns. These patterns include the respiratory muscles that, in both birdsong and speech, provide the power for vocalization. Perturbing respiratory pressure by a brief, irregularly timed injection of air into the cranial thoracic air sac during song elicited a compensatory reduction in the electrical activity of the abdominal expiratory muscles, both in hearing and deafened adult northern cardinals (Cardinalis cardinalis). This muscle response was absent or reduced during quiet respiration, suggesting it is specifically linked to phonation. Our findings indicate that somatosensory feedback to expiratory muscles elicits compensatory adjustments that help stabilize, in real time, the subsyringeal pressure against fluctuations caused by changes in posture or physical activity. PMID:11943843

  20. Early identification of motor delay

    PubMed Central

    Harris, Susan R.

    2016-01-01

    Objective To describe the Harris Infant Neuromotor Test (HINT), an infant neuromotor test using Canadian norms published in 2010 that could be used to screen for motor delay during the first year of life. Quality of evidence Extensive research has been published on the intrarater, interrater, and test-retest reliability and the content, concurrent, predictive, and known-groups validity of the HINT, as well as on the sensitivity, specificity, and positive and negative predictive values of parental concerns, as assessed by the HINT. Most evidence is level II. Main message Diagnosing motor delays during the first year of life is important because these often indicate more generalized developmental delays or specific disabilities, such as cerebral palsy. Parental concerns about their children’s motor development are strongly predictive of subsequent diagnoses involving motor delay. Conclusion Only through early identification of developmental motor delays, initially with screening tools such as the HINT, is it possible to provide referrals for early intervention that could benefit both the infant and the family. PMID:27521388

  1. Filament overwrapped motor case technology

    NASA Astrophysics Data System (ADS)

    Compton, Joel P.

    1993-11-01

    Atlantic Research Corporation (ARC) joined with the French Societe Europeenne de Propulsion (SEP) to develop and deliver to the U.S. Navy a small quantity of composite filament wound rocket motors to demonstrate a manufacturing technique that was being applied at the two companies. It was perceived that the manufacturing technique could produce motors that would be light in weight, inexpensive to produce, and that had a good chance of meeting insensitive munitions (IM) requirements that were being formulated by the Navy in the early 1980s. Under subcontract to ARC, SEP designed, tested, and delivered 2.75-inch rocket motors to the U.S. Navy for IM tests that were conducted in 1989 at China Lake, California. The program was one of the first to be founded by Nunn Amendment money. The Government-to-Government program was sponsored by the Naval Air Systems Command and was monitored by the Naval Surface Warfare Center, Indian Head (NSWC-IH), Maryland. The motor propellant that was employed was a new, extruded composite formulation that was under development at the Naval Surface Warfare Center. The following paper describes the highlights of the program and gives the results of structural and ballistic static tests and insensitive munitions tests that were conducted on demonstration motors.

  2. Three phase AC motor controller

    DOEpatents

    Vuckovich, Michael; Wright, Maynard K.; Burkett, John P.

    1984-03-20

    A motor controller for a three phase AC motor (10) which is adapted to operate bidirectionally from signals received either from a computer (30) or a manual control (32). The controller is comprised of digital logic circuit means which implement a forward and reverse command signal channel (27, 29) for the application of power through the forward and reverse power switching relays (16, 18, 20, 22). The digital logic elements are cross coupled to prevent activation of both channels simultaneously and each includes a plugging circuit (65, 67) for stopping the motor upon the removal of control signal applied to one of the two channels (27, 29) for a direction of rotation desired. Each plugging circuit (65, 67) includes a one-shot pulse signal generator (88, 102) which outputs a single pulse signal of predetermined pulsewidth which is adapted to inhibit further operation of the application of power in the channel which is being activated and to apply a reversal command signal to the other channel which provides a reversed phase application of power to the motor for a period defined by the pulse-width output of the one-shot signal generator to plug the motor (10) which will then be inoperative until another rotational command signal is applied to either of the two channels.

  3. Minimum Principles in Motor Control.

    PubMed

    Engelbrecht, Sascha E.

    2001-06-01

    Minimum (or minimal) principles are mathematical laws that were first used in physics: Hamilton's principle and Fermat's principle of least time are two famous example. In the past decade, a number of motor control theories have been proposed that are formally of the same kind as the minimum principles of physics, and some of these have been quite successful at predicting motor performance in a variety of tasks. The present paper provides a comprehensive review of this work. Particular attention is given to the relation between minimum theories in motor control and those used in other disciplines. Other issues around which the review is organized include: (1) the relation between minimum principles and structural models of motor planning and motor control, (2) the empirically-driven development of minimum principles and the danger of circular theorizing, and (3) the design of critical tests for minimum theories. Some perspectives for future research are discussed in the concluding section of the paper. Copyright 2001 Academic Press. PMID:11401453

  4. A miniscale ballistic test motor for propellant burning rate characterization from one motor firing

    NASA Astrophysics Data System (ADS)

    Rast, Robert H.; Boyles, Sharon M.; Obney, Phyllis

    1992-07-01

    A mini ballistic test motor for burn rate characterization from one motor firing has been developed. The small charge weight required for this motor allows ballistic characterization of small scale lot set evaluation and R&D propellant mixes in a rocket motor environment. This paper presents results comparing the mini-motor to the standard Naval Surface Warfare Center, Indian Head (IHDIVNAVSURFWARCEN) ballistic test motor, (BTM). Burn rate data from the standard BTM and mini BTM show excellent agreement.

  5. Control Circuit For Two Stepping Motors

    NASA Technical Reports Server (NTRS)

    Ratliff, Roger; Rehmann, Kenneth; Backus, Charles

    1990-01-01

    Control circuit operates two independent stepping motors, one at a time. Provides following operating features: After selected motor stepped to chosen position, power turned off to reduce dissipation; Includes two up/down counters that remember at which one of eight steps each motor set. For selected motor, step indicated by illumination of one of eight light-emitting diodes (LED's) in ring; Selected motor advanced one step at time or repeatedly at rate controlled; Motor current - 30 mA at 90 degree positions, 60 mA at 45 degree positions - indicated by high or low intensity of LED that serves as motor-current monitor; Power-on reset feature provides trouble-free starts; To maintain synchronism between control circuit and motors, stepping of counters inhibited when motor power turned off.

  6. DC link stabilized field oriented control of electric propulsion systems

    SciTech Connect

    Sudhoff, S.D.; Corzine, K.A.; Glover, S.F.; Hegner, H.J.; Robey, H.N. Jr.

    1998-03-01

    Induction motor based electric propulsion systems can be used in a wide variety of applications including locomotives, hybrid electric vehicles, and ships. Field oriented control of these drives is attractive since it allows the torque to be tightly and nearly instantaneously controlled. However, such systems can be prone to negative impedance instability of the DC link. This paper examines this type of instability and sets forth a readily implemented albeit nonlinear control strategy to mitigate this potential problem.

  7. Linked Ocean Data

    NASA Astrophysics Data System (ADS)

    Leadbetter, Adam; Arko, Robert; Chandler, Cynthia; Shepherd, Adam

    2014-05-01

    "Linked Data" is a term used in Computer Science to encapsulate a methodology for publishing data and metadata in a structured format so that links may be created and exploited between objects. Berners-Lee (2006) outlines the following four design principles of a Linked Data system: Use Uniform Resource Identifiers (URIs) as names for things. Use HyperText Transfer Protocol (HTTP) URIs so that people can look up those names. When someone looks up a URI, provide useful information, using the standards (Resource Description Framework [RDF] and the RDF query language [SPARQL]). Include links to other URIs so that they can discover more things. In 2010, Berners-Lee revisited his original design plan for Linked Data to encourage data owners along a path to "good Linked Data". This revision involved the creation of a five star rating system for Linked Data outlined below. One star: Available on the web (in any format). Two stars: Available as machine-readable structured data (e.g. An Excel spreadsheet instead of an image scan of a table). Three stars: As two stars plus the use of a non-proprietary format (e.g. Comma Separated Values instead of Excel). Four stars: As three stars plus the use of open standards from the World Wide Web Commission (W3C) (i.e. RDF and SPARQL) to identify things, so that people can point to your data and metadata. Five stars: All the above plus link your data to other people's data to provide context Here we present work building on the SeaDataNet common vocabularies served by the NERC Vocabulary Server, connecting projects such as the Rolling Deck to Repository (R2R) and the Biological and Chemical Oceanography Data Management Office (BCO-DMO) and other vocabularies such as the Marine Metadata Interoperability Ontology Register and Repository and the NASA Global Change Master Directory to create a Linked Ocean Data cloud. Publishing the vocabularies and metadata in standard RDF XML and exposing SPARQL endpoints renders them five-star Linked

  8. Linear Synchronous Motor Repeatability Tests

    SciTech Connect

    Ward, C.R.

    2002-10-18

    A cart system using linear synchronous motors was being considered for the Plutonium Immobilization Plant (PIP). One of the applications in the PIP was the movement of a stack of furnace trays, filled with the waste form (pucks) from a stacking/unstacking station to several bottom loaded furnaces. A system was ordered to perform this function in the PIP Ceramic Prototype Test Facility (CPTF). This system was installed and started up in SRTC prior to being installed in the CPTF. The PIP was suspended and then canceled after the linear synchronous motor system was started up. This system was used to determine repeatability of a linear synchronous motor cart system for the Modern Pit Facility.

  9. Remote control for motor vehicle

    NASA Technical Reports Server (NTRS)

    Johnson, Dale R. (Inventor); Ciciora, John A. (Inventor)

    1984-01-01

    A remote controller is disclosed for controlling the throttle, brake and steering mechanism of a conventional motor vehicle, with the remote controller being particularly advantageous for use by severely handicapped individuals. The controller includes a remote manipulator which controls a plurality of actuators through interfacing electronics. The remote manipulator is a two-axis joystick which controls a pair of linear actuators and a rotary actuator, with the actuators being powered by electric motors to effect throttle, brake and steering control of a motor vehicle adapted to include the controller. The controller enables the driver to control the adapted vehicle from anywhere in the vehicle with one hand with minimal control force and range of motion. In addition, even though a conventional vehicle is adapted for use with the remote controller, the vehicle may still be operated in the normal manner.

  10. Sleep-Dependent Reactivation of Ensembles in Motor Cortex Promotes Skill Consolidation

    PubMed Central

    Ramanathan, Dhakshin S.; Gulati, Tanuj; Ganguly, Karunesh

    2015-01-01

    Despite many prior studies demonstrating offline behavioral gains in motor skills after sleep, the underlying neural mechanisms remain poorly understood. To investigate the neurophysiological basis for offline gains, we performed single-unit recordings in motor cortex as rats learned a skilled upper-limb task. We found that sleep improved movement speed with preservation of accuracy. These offline improvements were linked to both replay of task-related ensembles during non-rapid eye movement (NREM) sleep and temporal shifts that more tightly bound motor cortical ensembles to movements; such offline gains and temporal shifts were not evident with sleep restriction. Interestingly, replay was linked to the coincidence of slow-wave events and bursts of spindle activity. Neurons that experienced the most consistent replay also underwent the most significant temporal shift and binding to the motor task. Significantly, replay and the associated performance gains after sleep only occurred when animals first learned the skill; continued practice during later stages of learning (i.e., after motor kinematics had stabilized) did not show evidence of replay. Our results highlight how replay of synchronous neural activity during sleep mediates large-scale neural plasticity and stabilizes kinematics during early motor learning. PMID:26382320

  11. Miniaturization of Planar Horn Motors

    NASA Technical Reports Server (NTRS)

    Sherrit, Stewart; Ostlund, Patrick N.; Chang, Zensheu; Bao, Xiaoqi; Bar-Cohen, Yoseph; Widholm, Scott E.; Badescu, Mircea

    2012-01-01

    There is a great need for compact, efficient motors for driving various mechanisms including robots or mobility platforms. A study is currently underway to develop a new type of piezoelectric actuators with significantly more strength, low mass, small footprint, and efficiency. The actuators/motors utilize piezoelectric actuated horns which have a very high power density and high electromechanical conversion efficiency. The horns are fabricated using our recently developed novel pre-stress flexures that make them thermally stable and increases their coupling efficiency. The monolithic design and integrated flexures that pre-stresses the piezoelectric stack eliminates the use of stress bolt. This design allows embedding solid-state motors and actuators in any structure so that the only macroscopically moving parts are the rotor or the linear translator. The developed actuator uses a stack/horn actuation and has a Barth motor configuration, which potentially generates very large torque and speeds that do not require gearing. Finite element modeling and design tools were investigated to determine the requirements and operation parameters and the results were used to design and fabricate a motor. This new design offers a highly promising actuation mechanism that can potentially be miniaturized and integrated into systems and structures. It can be configured in many shapes to operate as multi-degrees of freedom and multi-dimensional motors/actuators including unidirectional, bidirectional, 2D and 3D. In this manuscript, we are reporting the experimental measurements from a bench top design and the results from the efforts to miniaturize the design using 2x2x2 mm piezoelectric stacks integrated into thin plates that are of the order of3 x 3x 0.2 cm.

  12. Homopolar motor with dual rotors

    DOEpatents

    Hsu, John S.

    1998-01-01

    A homopolar motor (10) has a field rotor (15) mounted on a frame (11) for rotation in a first rotational direction and for producing an electromagnetic field, and an armature rotor (17) mounted for rotation on said frame (11) within said electromagnetic field and in a second rotational direction counter to said first rotational direction of said field rotor (15). The two rotors (15, 17) are coupled through a 1:1 gearing mechanism (19), so as to travel at the same speed but in opposite directions. This doubles the output voltage and output power, as compared to a motor in which only the armature is rotated. Several embodiments are disclosed.

  13. Homopolar motor with dual rotors

    DOEpatents

    Hsu, J.S.

    1998-12-01

    A homopolar motor has a field rotor mounted on a frame for rotation in a first rotational direction and for producing an electromagnetic field, and an armature rotor mounted for rotation on said frame within said electromagnetic field and in a second rotational direction counter to said first rotational direction of said field rotor. The two rotors are coupled through a 1:1 gearing mechanism, so as to travel at the same speed but in opposite directions. This doubles the output voltage and output power, as compared to a motor in which only the armature is rotated. Several embodiments are disclosed. 7 figs.

  14. Thermoelectric generator for motor vehicle

    DOEpatents

    Bass, John C.

    1997-04-29

    A thermoelectric generator for producing electric power for a motor vehicle from the heat of the exhaust gasses produced by the engine of the motor vehicle. The exhaust gasses pass through a finned heat transfer support structure which has seat positions on its outside surface for the positioning of thermoelectric modules. A good contact cylinder provides a framework from which a spring force can be applied to the thermoelectric modules to hold them in good contact on their seats on the surface of the heat transfer support structure.

  15. The Advanced Solid Rocket Motor

    NASA Astrophysics Data System (ADS)

    Mitchell, Royce E.

    1992-08-01

    The Advanced Solid Rocket Motor will utilize improved design features and automated manufacturing methods to produce an inherently safer propulsive system for the Space Shuttle and future launch systems. This second-generation motor will also provide an additional 12,000 pounds of payload to orbit, enhancing the utility and efficiency of the Shuttle system. The new plant will feature strip-wound, asbestos-free insulation; propellant continuous mixing and casting; and extensive robotic systems. Following a series of static tests at the Stennis Space Center, MS flights are targeted to begin in early 1997.

  16. Acute lower motor neuron tetraparesis.

    PubMed

    Añor, Sònia

    2014-11-01

    Flaccid nonambulatory tetraparesis or tetraplegia is an infrequent neurologic presentation; it is characteristic of neuromuscular disease (lower motor neuron [LMN] disease) rather than spinal cord disease. Paresis beginning in the pelvic limbs and progressing to the thoracic limbs resulting in flaccid tetraparesis or tetraplegia within 24 to 72 hours is a common presentation of peripheral nerve or neuromuscular junction disease. Complete body flaccidity develops with severe decrease or complete loss of spinal reflexes in pelvic and thoracic limbs. Animals with acute generalized LMN tetraparesis commonly show severe motor dysfunction in all limbs and severe generalized weakness in all muscles. PMID:25441630

  17. The Advanced Solid Rocket Motor

    NASA Technical Reports Server (NTRS)

    Mitchell, Royce E.

    1992-01-01

    The Advanced Solid Rocket Motor will utilize improved design features and automated manufacturing methods to produce an inherently safer propulsive system for the Space Shuttle and future launch systems. This second-generation motor will also provide an additional 12,000 pounds of payload to orbit, enhancing the utility and efficiency of the Shuttle system. The new plant will feature strip-wound, asbestos-free insulation; propellant continuous mixing and casting; and extensive robotic systems. Following a series of static tests at the Stennis Space Center, MS flights are targeted to begin in early 1997.

  18. Cross-linked informofers.

    PubMed Central

    Prosvirnin, V V; Ruzidic, S; Samarina, O P

    1979-01-01

    The proteins of 30S RNP particles containing pre-mRNA (hnRNA) were cross-linked with bifunctional reagents (dimethyl-suberimidate and dimethyl-3,3'-dithiobispropionimidate). Further treatment with 1 or 2 M NaCl dissociates all RNA from protein. However, a significant part of protein particles--informofers being cross-linked survived high salt treatment. Their sedimentation coefficients were close to those of original particles. No RNA could be detected in the informofers even after labeling the cells with a precursor for a long period of time. Sodium dodecylsulfate or urea dissociated cross-linked informofers into oligomeric polypeptides. They could be dissociated by beta-mercaptoethanol treatment if a reversible cross-linked reagent had been used. The resulting polypeptides were represented by informatin. RNP particles (30S RNP or poly-particles) were reconstituted upon mixing of cross-linked informofers with pre-mRNA and removal of 2 M NaCl. PMID:503864

  19. Predictive motor control of sensory dynamics in auditory active sensing.

    PubMed

    Morillon, Benjamin; Hackett, Troy A; Kajikawa, Yoshinao; Schroeder, Charles E

    2015-04-01

    Neuronal oscillations present potential physiological substrates for brain operations that require temporal prediction. We review this idea in the context of auditory perception. Using speech as an exemplar, we illustrate how hierarchically organized oscillations can be used to parse and encode complex input streams. We then consider the motor system as a major source of rhythms (temporal priors) in auditory processing, that act in concert with attention to sharpen sensory representations and link them across areas. We discuss the circuits that could mediate this audio-motor interaction, notably the potential role of the somatosensory system. Finally, we reposition temporal predictions in the context of internal models, discussing how they interact with feature-based or spatial predictions. We argue that complementary predictions interact synergistically according to the organizational principles of each sensory system, forming multidimensional filters crucial to perception. PMID:25594376

  20. Cerebellar Influence on Motor Cortex Plasticity: Behavioral Implications for Parkinson’s Disease

    PubMed Central

    Kishore, Asha; Meunier, Sabine; Popa, Traian

    2014-01-01

    Normal motor behavior involves the creation of appropriate activity patterns across motor networks, enabling firing synchrony, synaptic integration, and normal functioning of these networks. Strong topography-specific connections among the basal ganglia, cerebellum, and their projections to overlapping areas in the motor cortices suggest that these networks could influence each other’s plastic responses and functions. The defective striatal signaling in Parkinson’s disease (PD) could therefore lead to abnormal oscillatory activity and aberrant plasticity at multiple levels within the interlinked motor networks. Normal striatal dopaminergic signaling and cerebellar sensory processing functions influence the scaling and topographic specificity of M1 plasticity. Both these functions are abnormal in PD and appear to contribute to the abnormal M1 plasticity. Defective motor map plasticity and topographic specificity within M1 could lead to incorrect muscle synergies, which could manifest as abnormal or undesired movements, and as abnormal motor learning in PD. We propose that the loss of M1 plasticity in PD reflects a loss of co-ordination among the basal ganglia, cerebellar, and cortical inputs which translates to an abnormal plasticity of motor maps within M1 and eventually to some of the motor signs of PD. The initial benefits of dopamine replacement therapy on M1 plasticity and motor signs are lost during the progressive course of disease. Levodopa-induced dyskinesias in patients with advanced PD is linked to a loss of M1 sensorimotor plasticity and the attenuation of dyskinesias by cerebellar inhibitory stimulation is associated with restoration of M1 plasticity. Complimentary interventions should target reestablishing physiological communication between the striatal and cerebellar circuits, and within striato-cerebellar loop. This may facilitate correct motor synergies and reduce abnormal movements in PD. PMID:24834063

  1. Motor imagery facilitates force field learning.

    PubMed

    Anwar, Muhammad Nabeel; Tomi, Naoki; Ito, Koji

    2011-06-13

    Humans have the ability to produce an internal reproduction of a specific motor action without any overt motor output. Recent findings show that the processes underlying motor imagery are similar to those active during motor execution and both share common neural substrates. This suggests that the imagery of motor movements might play an important role in acquiring new motor skills. In this study we used haptic robot in conjunction with motor imagery technique to improve learning in a robot-based adaptation task. Two groups of subjects performed reaching movements with or without motor imagery in a velocity-dependent and position-dependent mixed force field. The groups performed movements with motor imagery produced higher after effects and decreased muscle co-contraction with respect to no-motor imagery group. These results showed a positive influence of motor imagery on acquiring new motor skill and suggest that motor learning can be facilitated by mental practice and could be used to increase the rate of adaptation. PMID:21555118

  2. SDRE control strategy applied to a nonlinear robotic including drive motor

    NASA Astrophysics Data System (ADS)

    de Lima, Jeferson J.; Tusset, Angelo M.; Janzen, Frederic C.; Piccirillo, Vinicius; Nascimento, Claudinor B.; Balthazar, José M.; Brasil, Reyolando M. L. R. da Fonseca

    2014-12-01

    A robotic control design considering all the inherent nonlinearities of the robot-engine configuration is developed. The interactions between the robot and joint motor drive mechanism are considered. The proposed control combines two strategies, one feedforward control in order to maintain the system in the desired coordinate, and feedback control system to take the system into a desired coordinate. The feedback control is obtained using State-Dependent Riccati Equation (SDRE). For link positioning two cases are considered. Case I: For control positioning, it is only used motor voltage; Case II: For control positioning, it is used both motor voltage and torque between the links. Simulation results, including parametric uncertainties in control shows the feasibility of the proposed control for the considered system.

  3. SDRE control strategy applied to a nonlinear robotic including drive motor

    SciTech Connect

    Lima, Jeferson J. de E-mail: tusset@utfpr.edu.br E-mail: piccirillo@utfpr.edu.br Tusset, Angelo M. E-mail: tusset@utfpr.edu.br E-mail: piccirillo@utfpr.edu.br Janzen, Frederic C. E-mail: tusset@utfpr.edu.br E-mail: piccirillo@utfpr.edu.br Piccirillo, Vinicius E-mail: tusset@utfpr.edu.br E-mail: piccirillo@utfpr.edu.br Nascimento, Claudinor B. E-mail: tusset@utfpr.edu.br E-mail: piccirillo@utfpr.edu.br; Balthazar, José M.; Brasil, Reyolando M. L. R. da Fonseca

    2014-12-10

    A robotic control design considering all the inherent nonlinearities of the robot-engine configuration is developed. The interactions between the robot and joint motor drive mechanism are considered. The proposed control combines two strategies, one feedforward control in order to maintain the system in the desired coordinate, and feedback control system to take the system into a desired coordinate. The feedback control is obtained using State-Dependent Riccati Equation (SDRE). For link positioning two cases are considered. Case I: For control positioning, it is only used motor voltage; Case II: For control positioning, it is used both motor voltage and torque between the links. Simulation results, including parametric uncertainties in control shows the feasibility of the proposed control for the considered system.

  4. Syllable Repetition vs. Finger Tapping: Aspects of Motor Timing in 100 Healthy Adults.

    PubMed

    Sundqvist, Maria; Johnels, Jakob Åsberg; Lindh, Jonas; Laakso, Katja; Hartelius, Lena

    2016-07-01

    In this study we systematically compared syllable repetition and finger tapping in healthy adults, and explored possible impacts of tempi, metronome, musical experience, and age on motor timing ability. One hundred healthy adults used finger-tapping and syllable repetition to perform an isochronous pulse in three different tempi, with and without a metronome. Results showed that the motor timing was more accurate with finger tapping than with syllable repetition in the slowest tempo, and the motor timing ability was better with the metronome than without. Persons with musical experience showed better motor timing accuracy than persons without such experience, and the timing asynchrony increased with increasing age. The slowest tempo 90 bpm posed extra challenges to the participants. We speculate that this pattern reflects the fact that the slow tempo lies outside the 3-8 Hz syllable rate of natural speech, which in turn has been linked to theta-based oscillations in the brain. PMID:26011921

  5. X-linked Agammaglobulinemia.

    PubMed

    Suri, Deepti; Rawat, Amit; Singh, Surjit

    2016-04-01

    X-linked agammaglobulinemia (XLA) is one of the commonest primary immune deficiencies encountered in pediatric clinical practice. In adults, common variable immunodeficiency (CVID) is the most common primary immunodeficiency disease (PID). It is an X-linked disorder characterized by increased susceptibility to encapsulated bacteria, severe hypergammaglobulinemia and absent circulating B cells in the peripheral blood. Replacement immunoglobulin therapy is the main cornerstone of treatment. Aggressive management of intercurrent infections and prophylactic antimicrobials are needed. This review attempts to highlight varied clinical manifestations and management of XLA, especially in the context of developing country. PMID:26909497

  6. Kinesin molecular motors: Transport pathways, receptors, and human disease

    NASA Astrophysics Data System (ADS)

    Goldstein, Lawrence S. B.

    2001-06-01

    Kinesin molecular motor proteins are responsible for many of the major microtubule-dependent transport pathways in neuronal and non-neuronal cells. Elucidating the transport pathways mediated by kinesins, the identity of the cargoes moved, and the nature of the proteins that link kinesin motors to cargoes are areas of intense investigation. Kinesin-II recently was found to be required for transport in motile and nonmotile cilia and flagella where it is essential for proper left-right determination in mammalian development, sensory function in ciliated neurons, and opsin transport and viability in photoreceptors. Thus, these pathways and proteins may be prominent contributors to several human diseases including ciliary dyskinesias, situs inversus, and retinitis pigmentosa. Kinesin-I is needed to move many different types of cargoes in neuronal axons. Two candidates for receptor proteins that attach kinesin-I to vesicular cargoes were recently found. One candidate, sunday driver, is proposed to both link kinesin-I to an unknown vesicular cargo and to bind and organize the mitogen-activated protein kinase components of a c-Jun N-terminal kinase signaling module. A second candidate, amyloid precursor protein, is proposed to link kinesin-I to a different, also unknown, class of axonal vesicles. The finding of a possible functional interaction between kinesin-I and amyloid precursor protein may implicate kinesin-I based transport in the development of Alzheimer's disease.

  7. Resolving Interference between Body Movements: Retrieval-Induced Forgetting of Motor Sequences

    ERIC Educational Resources Information Center

    Tempel, Tobias; Frings, Christian

    2013-01-01

    When body movements are stored in memory in an organized manner, linked to a common retrieval cue like the effector with which to execute the movement, interference may arise as soon as one initiates the execution of a specific body movement in the presence of the retrieval cue because related motor programs also are activated. We investigated the…

  8. Brief Report: Is Perceived Motor Competence a Constraint in Children's Action Planning?

    ERIC Educational Resources Information Center

    Gabbard, Carl; Cacola, Priscila; Cordova, Alberto

    2009-01-01

    A form of action representation of developmental interest is "reach estimation"--the perceptual and cognitive judgment of whether an object is within or out of reach. A common observation among children is overestimation, which, speculatively, has been linked to perceived motor competence (PMC). The authors examined the PMC effect on reachability…

  9. Closed-loop motor control using high-speed fiber optics

    NASA Technical Reports Server (NTRS)

    Dawson, Reginald (Inventor); Rodriquiz, Dagobert (Inventor)

    1991-01-01

    A closed-loop control system for controlling the operation of one or more servo motors or other controllable devices is described. The system employs a fiber optics link immune to electromagnetic interference, for transmission of control signals from a controller or controllers at a remote station to the power electronics located in proximity to the motors or other devices at the local station. At the remote station the electrical control signals are time-multiplexed, converted to a formatted serial bit stream, and converted to light signals for transmission over a single fiber of the fiber optics link. At the local station, the received optical signals are reconstructed as electrical control signals for the controlled motors or other devices. At the local station, an encoder sensor linked to the driven device generates encoded feedback signals which provide information as to a condition of the controlled device. The encoded signals are placed in a formatted serial bit stream, multiplexed, and transmitted as optical signals over a second fiber of the fiber optic link which closes the control loop of the closed-loop motor controller. The encoded optical signals received at the remote station are demultiplexed, reconstructed and coupled to the controller(s) as electrical feedback signals.

  10. Do Nimble Hands Make for Nimble Lexicons? Fine Motor Skills Predict Knowledge of Embodied Vocabulary Items

    ERIC Educational Resources Information Center

    Suggate, Sebastian P.; Stoeger, Heidrun

    2014-01-01

    Theories and research in embodied cognition postulate that cognition grounded in action enjoys a processing advantage. Extending this theory to the study of how fine motor skills (FMS) link to vocabulary development in preschool children, the authors investigated FMS and vocabulary in 76 preschoolers. Building on previous research, they…

  11. Associations between gross motor and communicative development in at-risk infants.

    PubMed

    LeBarton, Eve Sauer; Iverson, Jana M

    2016-08-01

    Infants' advances in locomotion relate to advances in communicative development. However, little is known about these relations in infants at risk for delays in these domains and whether they may extend to earlier achievements in gross motor development in infancy. We examined whether advances in sitting and prone locomotion are related to communicative development in infants who have an older sibling with autism spectrum disorder (ASD) and are at risk for motor and communication delays (heightened-risk; HR). We conducted a longitudinal study with 37 HR infants who did not receive an ASD diagnosis at 36 months. Infants were observed monthly between the ages of 5 and 14 months. We assessed gross motor development using the Alberta Infant Motor Scales (AIMS) and recorded ages of onset of verbal and nonverbal communicative behaviors. Results indicated increased presence of early gross motor delay from 5 to 10 months. In addition, there were positive relations between sitting and gesture and babble onset and between prone development and gesture onset. Thus, links between gross motor development and communication extend to at-risk development and provide a starting point for future research on potential cascading consequences of motor advances on communication development. PMID:27314943

  12. Microtubule organization by the antagonistic mitotic motors kinesin-5 and kinesin-14

    PubMed Central

    Hentrich, Christian

    2010-01-01

    During cell division, different molecular motors act synergistically to rearrange microtubules. Minus end–directed motors are thought to have a dual role: focusing microtubule ends to poles and establishing together with plus end–directed motors a balance of force between antiparallel microtubules in the spindle. We study here the competing action of Xenopus laevis kinesin-14 and -5 in vitro in situations in which these motors with opposite directionality cross-link and slide microtubules. We find that full-length kinesin-14 can form microtubule asters without additional factors, whereas kinesin-5 does not, likely reflecting an adaptation to mitotic function. A stable balance of force is not established between two antiparallel microtubules with these motors. Instead, directional instability is generated, promoting efficient motor and microtubule sorting. A nonmotor microtubule cross-linker can suppress directional instability but also impedes microtubule sorting, illustrating a conflict between stability and dynamicity of organization. These results establish the basic organizational properties of these antagonistic mitotic motors and a microtubule bundler. PMID:20439998

  13. Temporal dynamics of motor cortex excitability during perception of natural emotional scenes

    PubMed Central

    Borgomaneri, Sara; Gazzola, Valeria

    2014-01-01

    Although it is widely assumed that emotions prime the body for action, the effects of visual perception of natural emotional scenes on the temporal dynamics of the human motor system have scarcely been investigated. Here, we used single-pulse transcranial magnetic stimulation (TMS) to assess motor excitability during observation and categorization of positive, neutral and negative pictures from the International Affective Picture System database. Motor-evoked potentials (MEPs) from TMS of the left motor cortex were recorded from hand muscles, at 150 and 300 ms after picture onset. In the early temporal condition we found an increase in hand motor excitability that was specific for the perception of negative pictures. This early negative bias was predicted by interindividual differences in the disposition to experience aversive feelings (personal distress) in interpersonal emotional contexts. In the later temporal condition, we found that MEPs were similarly increased for both positive and negative pictures, suggesting an increased reactivity to emotionally arousing scenes. By highlighting the temporal course of motor excitability during perception of emotional pictures, our study provides direct neurophysiological support for the evolutionary notions that emotion perception is closely linked to action systems and that emotionally negative events require motor reactions to be more urgently mobilized. PMID:23945998

  14. Self-organization of waves and pulse trains by molecular motors in cellular protrusions.

    PubMed

    Yochelis, A; Ebrahim, S; Millis, B; Cui, R; Kachar, B; Naoz, M; Gov, N S

    2015-01-01

    Actin-based cellular protrusions are an ubiquitous feature of cells, performing a variety of critical functions ranging from cell-cell communication to cell motility. The formation and maintenance of these protrusions relies on the transport of proteins via myosin motors, to the protrusion tip. While tip-directed motion leads to accumulation of motors (and their molecular cargo) at the protrusion tip, it is observed that motors also form rearward moving, periodic and isolated aggregates. The origins and mechanisms of these aggregates, and whether they are important for the recycling of motors, remain open puzzles. Motivated by novel myosin-XV experiments, a mass conserving reaction-diffusion-advection model is proposed. The model incorporates a non-linear cooperative interaction between motors, which converts them between an active and an inactive state. Specifically, the type of aggregate formed (traveling waves or pulse-trains) is linked to the kinetics of motors at the protrusion tip which is introduced by a boundary condition. These pattern selection mechanisms are found not only to qualitatively agree with empirical observations but open new vistas to the transport phenomena by molecular motors in general. PMID:26335545

  15. Self-organization of waves and pulse trains by molecular motors in cellular protrusions

    PubMed Central

    Yochelis, A.; Ebrahim, S.; Millis, B.; Cui, R.; Kachar, B.; Naoz, M.; Gov, N. S.

    2015-01-01

    Actin-based cellular protrusions are an ubiquitous feature of cells, performing a variety of critical functions ranging from cell-cell communication to cell motility. The formation and maintenance of these protrusions relies on the transport of proteins via myosin motors, to the protrusion tip. While tip-directed motion leads to accumulation of motors (and their molecular cargo) at the protrusion tip, it is observed that motors also form rearward moving, periodic and isolated aggregates. The origins and mechanisms of these aggregates, and whether they are important for the recycling of motors, remain open puzzles. Motivated by novel myosin-XV experiments, a mass conserving reaction-diffusion-advection model is proposed. The model incorporates a non-linear cooperative interaction between motors, which converts them between an active and an inactive state. Specifically, the type of aggregate formed (traveling waves or pulse-trains) is linked to the kinetics of motors at the protrusion tip which is introduced by a boundary condition. These pattern selection mechanisms are found not only to qualitatively agree with empirical observations but open new vistas to the transport phenomena by molecular motors in general. PMID:26335545

  16. Evolution of EEG Motor Rhythms after Spinal Cord Injury: A Longitudinal Study.

    PubMed

    López-Larraz, Eduardo; Montesano, Luis; Gil-Agudo, Ángel; Minguez, Javier; Oliviero, Antonio

    2015-01-01

    Spinal cord injury (SCI) does not only produce a lack of sensory and motor function caudal to the level of injury, but it also leads to a progressive brain reorganization. Chronic SCI patients attempting to move their affected limbs present a significant reduction of brain activation in the motor cortex, which has been linked to the deafferentation. The aim of this work is to study the evolution of the motor-related brain activity during the first months after SCI. Eighteen subacute SCI patients were recruited to participate in bi-weekly experimental sessions during at least two months. Their EEG was recorded to analyze the temporal evolution of the event-related desynchronization (ERD) over the motor cortex, both during motor attempt and motor imagery of their paralyzed hands. The results show that the α and β ERD evolution after SCI is negatively correlated with the clinical progression of the patients during the first months after the injury. This work provides the first longitudinal study of the event-related desynchronization during the subacute phase of spinal cord injury. Furthermore, our findings reveal a strong association between the ERD changes and the clinical evolution of the patients. These results help to better understand the brain transformation after SCI, which is important to characterize the neuroplasticity mechanisms involved after this lesion and may lead to new strategies for rehabilitation and motor restoration of these patients. PMID:26177457

  17. Evolution of EEG Motor Rhythms after Spinal Cord Injury: A Longitudinal Study

    PubMed Central

    López-Larraz, Eduardo; Montesano, Luis; Gil-Agudo, Ángel; Minguez, Javier; Oliviero, Antonio

    2015-01-01

    Spinal cord injury (SCI) does not only produce a lack of sensory and motor function caudal to the level of injury, but it also leads to a progressive brain reorganization. Chronic SCI patients attempting to move their affected limbs present a significant reduction of brain activation in the motor cortex, which has been linked to the deafferentation. The aim of this work is to study the evolution of the motor-related brain activity during the first months after SCI. Eighteen subacute SCI patients were recruited to participate in bi-weekly experimental sessions during at least two months. Their EEG was recorded to analyze the temporal evolution of the event-related desynchronization (ERD) over the motor cortex, both during motor attempt and motor imagery of their paralyzed hands. The results show that the α and β ERD evolution after SCI is negatively correlated with the clinical progression of the patients during the first months after the injury. This work provides the first longitudinal study of the event-related desynchronization during the subacute phase of spinal cord injury. Furthermore, our findings reveal a strong association between the ERD changes and the clinical evolution of the patients. These results help to better understand the brain transformation after SCI, which is important to characterize the neuroplasticity mechanisms involved after this lesion and may lead to new strategies for rehabilitation and motor restoration of these patients. PMID:26177457

  18. Transport of Beads by Several Kinesin Motors

    PubMed Central

    Beeg, Janina; Klumpp, Stefan; Dimova, Rumiana; Gracià, Rubèn Serral; Unger, Eberhard; Lipowsky, Reinhard

    2008-01-01

    The movements of beads pulled by several kinesin-1 (conventional kinesin) motors are studied both theoretically and experimentally. While the velocity is approximately independent of the number of motors pulling the beads, the walking distance or run-length is strongly increased when more motors are involved. Run-length distributions are measured for a wide range of motor concentrations and matched to theoretically calculated distributions using only two global fit parameters. In this way, the maximal number of motors pulling the beads is estimated to vary between two and seven motors for total kinesin concentrations between 0.1 and 2.5 μg/ml or between 0.27 and 6.7 nM. In the same concentration regime, the average number of pulling motors is found to lie between 1.1 and 3.2 motors. PMID:17872957

  19. Transport of beads by several kinesin motors.

    PubMed

    Beeg, Janina; Klumpp, Stefan; Dimova, Rumiana; Gracià, Rubèn Serral; Unger, Eberhard; Lipowsky, Reinhard

    2008-01-15

    The movements of beads pulled by several kinesin-1 (conventional kinesin) motors are studied both theoretically and experimentally. While the velocity is approximately independent of the number of motors pulling the beads, the walking distance or run-length is strongly increased when more motors are involved. Run-length distributions are measured for a wide range of motor concentrations and matched to theoretically calculated distributions using only two global fit parameters. In this way, the maximal number of motors pulling the beads is estimated to vary between two and seven motors for total kinesin concentrations between 0.1 and 2.5 microg/ml or between 0.27 and 6.7 nM. In the same concentration regime, the average number of pulling motors is found to lie between 1.1 and 3.2 motors. PMID:17872957

  20. Chemistry: No turning back for motorized molecules

    NASA Astrophysics Data System (ADS)

    Clayden, Jonathan

    2016-06-01

    Two molecular motors have been developed that use chemical energy to drive rotational motion in a single direction. The findings bring the prospect of devices powered by such motors a tantalizing step closer. See Letter p.235

  1. Trophic Factor Expression in Phrenic Motor Neurons

    PubMed Central

    Mantilla, Carlos B.; Sieck, Gary C.

    2008-01-01

    The function of a motor neuron and the muscle fibers it innervates (i.e., a motor unit) determines neuromotor output. Unlike other skeletal muscles, respiratory muscles (e.g., the diaphragm, DIAm) must function from birth onwards in sustaining ventilation. DIAm motor units are capable of both ventilatory and non-ventilatory behaviors, including expulsive behaviors important for airway clearance. There is significant diversity in motor unit properties across different types of motor units in the DIAm. The mechanisms underlying the development and maintenance of motor unit diversity in respiratory muscles (including the DIAm) are not well understood. Recent studies suggest that trophic factor influences contribute to this diversity. Remarkably little is known about the expression of trophic factors and their receptors in phrenic motor neurons. This review will focus on the contribution of trophic factors to the establishment and maintenance of motor unit diversity in the DIAm, during development and in response to injury or disease. PMID:18708170

  2. CDC Vital Signs: Motor Vehicle Crash Deaths

    MedlinePlus

    ... Press Kit Read the MMWR Science Clips Motor Vehicle Crash Deaths How is the US doing? Language: ... Sweden, Switzerland, and the United Kingdom. Problem Motor vehicle crash deaths in the US are still too ...

  3. Reducing Stepping-Motor Power Consumption

    NASA Technical Reports Server (NTRS)

    Williams, C. J.

    1985-01-01

    Direct-current stepping motors used in computer peripherals, process control, and precision remote-positioning equipment constantly dissipate power and create heat even when not moving. Circuit design energizes stepper motor only when pulses are present on control input.

  4. Experimental thermodynamics of single molecular motor

    PubMed Central

    Toyabe, Shoichi; Muneyuki, Eiro

    2013-01-01

    Molecular motor is a nano-sized chemical engine that converts chemical free energy to mechanical motions. Hence, the energetics is as important as kinetics in order to understand its operation principle. We review experiments to evaluate the thermodynamic properties of a rotational F1-ATPase motor (F1-motor) at a single-molecule level. We show that the F1-motor achieves 100% thermo dynamic efficiency at the stalled state. Furthermore, the motor reduces the internal irreversible heat inside the motor to almost zero and achieves a highly-efficient free energy transduction close to 100% during rotations far from quasistatic process. We discuss the mechanism of how the F1-motor achieves such a high efficiency, which highlights the remarkable property of the nano-sized engine F1-motor. PMID:27493546

  5. Failure analysis of solid rocket apogee motors

    NASA Technical Reports Server (NTRS)

    Martin, P. J.

    1972-01-01

    The analysis followed five selected motors through initial design, development, test, qualification, manufacture, and final flight reports. An audit was conducted at the manufacturing plants to complement the literature search with firsthand observations of the current philosophies and practices that affect reliability of the motors. A second literature search emphasized acquisition of spacecraft and satellite data bearing on solid motor reliability. It was concluded that present practices at the plants yield highly reliable flight hardware. Reliability can be further improved by new developments of aft-end bonding and initiator/igniter nondestructive test methods, a safe/arm device, and an insulation formulation. Minimum diagnostic instrumentation is recommended for all motor flights. Surplus motors should be used in margin testing. Criteria should be established for pressure and zone curing. The motor contractor should be represented at launch. New design analyses should be made of stretched motors and spacecraft/motor pairs.

  6. Small-Scale Rocket Motor Test

    NASA Video Gallery

    Engineers at NASA's Marshall Space Flight Center in Huntsville, Ala. successfully tested a sub-scale solid rocket motor on May 27. Testing a sub-scale version of a rocket motor is a cost-effective ...

  7. Improving Motor Skills through Listening

    ERIC Educational Resources Information Center

    Wang, Lin

    2004-01-01

    In this article, the author discusses how to improve a child's motor skills through listening by using three simple steps--recording the auditory model, determining when to use the auditory model, and considering where to use the auditory model. She points out the importance of using a demonstration technique that helps learners understand the…

  8. Motor control of fly feeding.

    PubMed

    McKellar, Claire E

    2016-06-01

    Following considerable progress on the molecular and cellular basis of taste perception in fly sensory neurons, the time is now ripe to explore how taste information, integrated with hunger and satiety, undergo a sensorimotor transformation to lead to the motor actions of feeding behavior. I examine what is known of feeding circuitry in adult flies from more than 250 years of work in larger flies and from newer work in Drosophila. I review the anatomy of the proboscis, its muscles and their functions (where known), its motor neurons, interneurons known to receive taste inputs, interneurons that diverge from taste circuitry to provide information to other circuits, interneurons from other circuits that converge on feeding circuits, proprioceptors that influence the motor control of feeding, and sites of integration of hunger and satiety on feeding circuits. In spite of the several neuron types now known, a connected pathway from taste inputs to feeding motor outputs has yet to be found. We are on the threshold of an era where these individual components will be assembled into circuits, revealing how nervous system architecture leads to the control of behavior. PMID:27309215

  9. Motor Action and Emotional Memory

    ERIC Educational Resources Information Center

    Casasanto, Daniel; Dijkstra, Katinka

    2010-01-01

    Can simple motor actions affect how efficiently people retrieve emotional memories, and influence what they choose to remember? In Experiment 1, participants were prompted to retell autobiographical memories with either positive or negative valence, while moving marbles either upward or downward. They retrieved memories faster when the direction…

  10. ELECTRIC MOTORS FOR FARM USE.

    ERIC Educational Resources Information Center

    Illinois Univ., Urbana. Coll. of Agriculture.

    BETWEEN 2 AND 8 HOURS ARE REQUIRED FOR USE OF THIS TEXTUAL OR REFERENCE MATERIAL ON ELECTRIC MOTORS. IT WAS DEVELOPED BY AN AGRICULTURAL EDUCATION-AGRICULTURAL ENGINEERING SPECIALIST ON THE BASIS OF CONFERENCES WITH SUBJECT MATTER SPECIALISTS, TEACHER EDUCATORS, SUPERVISORS, AND TEACHERS. THE OBJECTIVES AND SUBJECT MATTER CENTER AROUND THE…

  11. Technology and Motor Ability Development

    ERIC Educational Resources Information Center

    Wang, Lin; Lang, Yong; Luo, Zhongmin

    2014-01-01

    As a new member joining the technology family, active video games have been developed to promote physical exercise. This working-in-progress paper shares an ongoing project on examining the basic motor abilities that are enhanced through participating in commercially available active video games. [For the full proceedings see ED557181.

  12. Stages of motor skill learning.

    PubMed

    Luft, Andreas R; Buitrago, Manuel M

    2005-12-01

    Successful learning of a motor skill requires repetitive training. Once the skill is mastered, it can be remembered for a long period of time. The durable memory makes motor skill learning an interesting paradigm for the study of learning and memory mechanisms. To gain better understanding, one scientific approach is to dissect the process into stages and to study these as well as their interactions. This article covers the growing evidence that motor skill learning advances through stages, in which different storage mechanisms predominate. The acquisition phase is characterized by fast (within session) and slow learning (between sessions). For a short period following the initial training sessions, the skill is labile to interference by other skills and by protein synthesis inhibition, indicating that consolidation processes occur during rest periods between training sessions. During training as well as rest periods, activation in different brain regions changes dynamically. Evidence for stages in motor skill learning is provided by experiments using behavioral, electrophysiological, functional imaging, and cellular/molecular methods. PMID:16385137

  13. Motor vehicle safety during pregnancy

    PubMed Central

    Vladutiu, Catherine J.; Weiss, Harold B.

    2013-01-01

    Motor vehicle crashes during pregnancy are the leading cause of traumatic fetal mortality and serious maternal injury morbidity and mortality in the United States, injuring approximately 92,500 pregnant women each year. Little is known about the circumstances surrounding these crash events and the maternal characteristics that may increase women’s vulnerability to crash-related injuries during pregnancy. Even less is known about the effects of crashes on fetal outcomes. Crash simulation studies using female anthropomorphic test devices and computational models have been conducted to better understand the mechanisms of maternal and fetal injuries and death resulting from motor vehicle crashes. In addition, several case reports describing maternal and fetal outcomes following crashes have been published in the literature. Only a few population-based studies have explored the association between motor vehicle crashes and adverse maternal and/or fetal outcomes and even fewer have examined the effectiveness of seat belts and/or airbags in reducing the risk of these outcomes. This paper reviews what is presently known about motor vehicle crashes during pregnancy, their effects on maternal and fetal outcomes, and the role of vehicle safety devices and other safety approaches in mitigating the occurrence and severity of maternal crashes and subsequent injuries. In addition, this paper suggests interventions targeted towards the prevention of crashes during pregnancy. PMID:23710161

  14. Ironless-armature brushless motor

    NASA Technical Reports Server (NTRS)

    Fisher, R. L.

    1977-01-01

    Device uses 12-pole samarium cobalt permanent-magnet rotor and three Hall-effect sensors for commutation. In prototype motor, torque constant (3-phase delta) is 65 oz-in/amp; electrical time constant (L/R) is 0.2 x 0.001 sec, and armature resistance is 20 ohms.

  15. Molecular Motors and Synaptic Assembly

    PubMed Central

    Cai, Qian; Sheng, Zu-Hang

    2016-01-01

    Proper synaptic function requires the seamless integration of the transport, assembly, and regulation of synaptic components and structures. Inasmuch as the synapse is often distant from the neuronal cell body, newly synthesized synaptic proteins, the precursors of synaptic vesicles, active zone compartments, channels and receptors, and mitochondria, must be transported along lengthy neuronal processes to participate in synaptogenesis. Neuronal transport is mediated by motor proteins that associate with their cargoes via adaptors (or receptors) and that travel along the cytoskeleton network within the neuronal processes. Thus, the identity of membranous protein cargoes and the specificity of motor-cargo interactions are critical for correctly targeting cargoes and properly assembling synapses in developing neurons and in remodeling synapses of mature neurons in response to neuronal activity. In this article, the authors review recent progress in characterizing microtubule- and actin-based motor proteins that are involved in delivering synaptic components and discuss potential mechanisms underlying the formation of motor- receptor-cargo complexes that contribute to synaptogenesis and activity-induced synaptic plasticity. PMID:19218232

  16. Motor interference in interactive contexts.

    PubMed

    Chinellato, Eris; Castiello, Umberto; Sartori, Luisa

    2015-01-01

    Action observation and execution share overlapping neural substrates, so that simultaneous activation by observation and execution modulates motor performance. Previous literature on simple prehension tasks has revealed that motor influence can be two-sided: facilitation for observed and performed congruent actions and interference for incongruent actions. But little is known of the specific modulations of motor performance in complex forms of interaction. Is it possible that the very same observed movement can lead either to interference or facilitation effects on a temporally overlapping congruent executed action, depending on the context? To answer this question participants were asked to perform a reach-to-grasp movement adopting a precision grip (PG) while: (i) observing a fixation cross, (ii) observing an actor performing a PG with interactive purposes, (iii) observing an actor performing a PG without interactive purposes. In particular, in the interactive condition the actor was shown trying to pour some sugar on a large cup located out of her reach but close to the participant watching the video, thus eliciting in reaction a complementary whole-hand grasp. Notably, fine-grained kinematic analysis for this condition revealed a specific delay in the grasping and reaching components and an increased trajectory deviation despite the observed and executed movement's congruency. Moreover, early peaks of trajectory deviation seem to indicate that socially relevant stimuli are acknowledged by the motor system very early. These data suggest that interactive contexts can determine a prompt modulation of stimulus-response compatibility effects. PMID:26113835

  17. Multisensory integration during motor planning.

    PubMed

    Sober, Samuel J; Sabes, Philip N

    2003-08-01

    When planning goal-directed reaches, subjects must estimate the position of the arm by integrating visual and proprioceptive signals from the sensory periphery. These integrated position estimates are required at two stages of motor planning: first to determine the desired movement vector, and second to transform the movement vector into a joint-based motor command. We quantified the contributions of each sensory modality to the position estimate formed at each planning stage. Subjects made reaches in a virtual reality environment in which vision and proprioception were dissociated by shifting the location of visual feedback. The relative weighting of vision and proprioception at each stage was then determined using computational models of feedforward motor control. We found that the position estimate used for movement vector planning relies mostly on visual input, whereas the estimate used to compute the joint-based motor command relies more on proprioceptive signals. This suggests that when estimating the position of the arm, the brain selects different combinations of sensory input based on the computation in which the resulting estimate will be used. PMID:12904459

  18. NASA's Advanced solid rocket motor

    NASA Astrophysics Data System (ADS)

    Mitchell, Royce E.

    The Advanced Solid Rocket Motor (ASRM) will not only bring increased safety, reliability and performance for the Space Shuttle Booster, it will enhance overall Shuttle safety by effectively eliminating 174 failure points in the Space Shuttle Main Engine throttling system and by reducing the exposure time to aborts due to main engine loss or shutdown. In some missions, the vulnerability time to Return-to-Launch Site aborts is halved. The ASRM uses case joints which will close or remain static under the effects of motor ignition and pressurization. The case itself is constructed of the weldable steel alloy HP 9-4-0.30, having very high strength and with superior fracture toughness and stress corrosion resistance. The internal insulation is strip-wound and is free of asbestos. The nozzle employs light weight ablative parts and is some 5,000 pounds lighter than the Shuttle motor used to date. The payload performance of the ASRM-powered Shuttle is 12,000 pounds higher than that provided by the present motor. This is of particular benefit for payloads delivered to higher inclinations and/or altitudes. The ASRM facility uses state-of-the-art manufacturing techniques, including continuous propellant mixing and direct casting.

  19. NASA's Advanced solid rocket motor

    NASA Technical Reports Server (NTRS)

    Mitchell, Royce E.

    1993-01-01

    The Advanced Solid Rocket Motor (ASRM) will not only bring increased safety, reliability and performance for the Space Shuttle Booster, it will enhance overall Shuttle safety by effectively eliminating 174 failure points in the Space Shuttle Main Engine throttling system and by reducing the exposure time to aborts due to main engine loss or shutdown. In some missions, the vulnerability time to Return-to-Launch Site aborts is halved. The ASRM uses case joints which will close or remain static under the effects of motor ignition and pressurization. The case itself is constructed of the weldable steel alloy HP 9-4-0.30, having very high strength and with superior fracture toughness and stress corrosion resistance. The internal insulation is strip-wound and is free of asbestos. The nozzle employs light weight ablative parts and is some 5,000 pounds lighter than the Shuttle motor used to date. The payload performance of the ASRM-powered Shuttle is 12,000 pounds higher than that provided by the present motor. This is of particular benefit for payloads delivered to higher inclinations and/or altitudes. The ASRM facility uses state-of-the-art manufacturing techniques, including continuous propellant mixing and direct casting.

  20. Molecular motors and their functions in plants

    NASA Technical Reports Server (NTRS)

    Reddy, A. S.

    2001-01-01

    Molecular motors that hydrolyze ATP and use the derived energy to generate force are involved in a variety of diverse cellular functions. Genetic, biochemical, and cellular localization data have implicated motors in a variety of functions such as vesicle and organelle transport, cytoskeleton dynamics, morphogenesis, polarized growth, cell movements, spindle formation, chromosome movement, nuclear fusion, and signal transduction. In non-plant systems three families of molecular motors (kinesins, dyneins, and myosins) have been well characterized. These motors use microtubules (in the case of kinesines and dyneins) or actin filaments (in the case of myosins) as tracks to transport cargo materials intracellularly. During the last decade tremendous progress has been made in understanding the structure and function of various motors in animals. These studies are yielding interesting insights into the functions of molecular motors and the origin of different families of motors. Furthermore, the paradigm that motors bind cargo and move along cytoskeletal tracks does not explain the functions of some of the motors. Relatively little is known about the molecular motors and their roles in plants. In recent years, by using biochemical, cell biological, molecular, and genetic approaches a few molecular motors have been isolated and characterized from plants. These studies indicate that some of the motors in plants have novel features and regulatory mechanisms. The role of molecular motors in plant cell division, cell expansion, cytoplasmic streaming, cell-to-cell communication, membrane trafficking, and morphogenesis is beginning to be understood. Analyses of the Arabidopsis genome sequence database (51% of genome) with conserved motor domains of kinesin and myosin families indicates the presence of a large number (about 40) of molecular motors and the functions of many of these motors remain to be discovered. It is likely that many more motors with novel regulatory

  1. Motor skill learning is associated with diffusion characteristics of white matter in individuals with chronic stroke

    PubMed Central

    Borich, Michael R.; Brown, Katlyn E.; Boyd, Lara A.

    2013-01-01

    Background and Purpose Imaging advances allow investigation of white matter following stroke; a growing body of literature has shown links between diffusion-based measures of white matter microstructure and motor function. However, the relationship between these measures and motor skill learning has not been considered in individuals with stroke. The aim of this study was to investigate the relationships between post-training white matter microstructural status, as indexed by diffusion tensor imaging (DTI) within the ipsilesional posterior limb of the internal capsule (PLIC) and learning of a novel motor task in individuals with chronic stroke. Methods Thirteen participants with chronic stroke and nine healthy controls practiced a visuomotor pursuit task across five sessions. Change in motor behavior associated with learning was indexed by comparing baseline performance with a delayed retention test. Fractional anisotropy (FA) indexed at the retention test was the primary DTI-derived outcome measure. Results In individuals with chronic stroke, we discovered an association between post-training ipsilesional PLIC FA and the magnitude of change associated with motor learning; hierarchical multiple linear regression analyses revealed that the combination of age, time post stroke and ipsilesional PLIC FA post-training was associated with motor learning related change (R2=0.649, p=0.02). Baseline motor performance was not related to post-training ipsilesional PLIC FA. Discussion and Conclusions Diffusion characteristics of post-training ipsilesional PLIC were linked to magnitude of change in skilled motor behavior. These results imply that the microstructural properties of regional white matter indexed by diffusion behavior may be an important factor to consider when determining potential response to rehabilitation in persons with stroke. Video Abstract available (See Video, Supplemental Digital Content 1.) for more insights from the authors. PMID:23934017

  2. Force Generation by Molecular-Motor-Powered Microtubule Bundles; Implications for Neuronal Polarization and Growth

    PubMed Central

    Jakobs, Maximilian; Franze, Kristian; Zemel, Assaf

    2015-01-01

    The heavily cross-linked microtubule (MT) bundles found in neuronal processes play a central role in the initiation, growth and maturation of axons and dendrites; however, a quantitative understanding of their mechanical function is still lacking. We here developed computer simulations to investigate the dynamics of force generation in 1D bundles of MTs that are cross-linked and powered by molecular motors. The motion of filaments and the forces they exert are investigated as a function of the motor type (unipolar or bipolar), MT density and length, applied load, and motor connectivity. We demonstrate that only unipolar motors (e.g., kinesin-1) can provide the driving force for bundle expansion, while bipolar motors (e.g., kinesin-5) oppose it. The force generation capacity of the bundles is shown to depend sharply on the fraction of unipolar motors due to a percolation transition that must occur in the bundle. Scaling laws between bundle length, force, MT length and motor fraction are presented. In addition, we investigate the dynamics of growth in the presence of a constant influx of MTs. Beyond a short equilibration period, the bundles grow linearly in time. In this growth regime, the bundle extends as one mass forward with most filaments sliding with the growth velocity. The growth velocity is shown to be dictated by the inward flux of MTs, to inversely scale with the load and to be independent of the free velocity of the motors. These findings provide important molecular-level insights into the mechanical function of the MT cytoskeleton in normal axon growth and regeneration after injury. PMID:26617489

  3. Magnetic motor evoked potentials in ponies.

    PubMed

    Mayhew, I G; Washbourne, J R

    1996-01-01

    Magnetic stimulation of motor pathways was used to effect motor unit action potential recordings from forelimb and hindlimb muscles in unanesthetized ponies. Motor pathway conduction velocities to the forelimb and hindlimb were determined to be 53.8 +/- 9.6 m/s-1 and 63.4 +/- 8.3 m/s-1, respectively. This noninvasive technique will enable more precise evaluation of motor deficits in clinical patients than is possible with the neurological examination. PMID:8884720

  4. Motorized control for mirror mount apparatus

    DOEpatents

    Cutburth, Ronald W.

    1989-01-01

    A motorized control and automatic braking system for adjusting mirror mount apparatus is disclosed. The motor control includes a planetary gear arrangement to provide improved pitch adjustment capability while permitting a small packaged design. The motor control for mirror mount adjustment is suitable for laser beam propagation applications. The brake is a system of constant contact, floating detents which engage the planetary gear at selected between-teeth increments to stop rotation instantaneously when the drive motor stops.

  5. Frequency modulation drive for a piezoelectric motor

    DOEpatents

    Mittas, Anthony

    2001-01-01

    A piezoelectric motor has peak performance at a specific frequency f.sub.1 that may vary over a range of frequencies. A drive system is disclosed for operating such a motor at peak performance without feedback. The drive system consists of the motor and an ac source connected to power the motor, the ac source repeatedly generating a frequency over a range from f.sub.1 -.DELTA.x to f.sub.1 +.DELTA.y.

  6. Helically linked mirror arrangement

    SciTech Connect

    Ranjan, P.

    1986-08-01

    A scheme is described for helical linking of mirror sections, which endeavors to combine the better features of toroidal and mirror devices by eliminating the longitudinal loss of mirror machines, having moderately high average ..beta.. and steady state operation. This scheme is aimed at a device, with closed magnetic surfaces having rotational transform for equilibrium, one or more axisymmetric straight sections for reduced radial loss, a simple geometrical axis for the links and an overall positive magnetic well depth for stability. We start by describing several other attempts at linking of mirror sections, made both in the past and the present. Then a description of our helically linked mirror scheme is given. This example has three identical straight sections connected by three sections having helical geometric axes. A theoretical analysis of the magnetic field and single-particle orbits in them leads to the conclusion that most of the passing particles would be confined in the device and they would have orbits independent of pitch angle under certain conditions. Numerical results are presented, which agree well with the theoretical results as far as passing particle orbits are concerned.

  7. Australian Curriculum Linked Lessons

    ERIC Educational Resources Information Center

    Hurrell, Derek; O'Neil, Jennifer

    2011-01-01

    In providing a continued focus on tasks and activities that help to illustrate key ideas embedded in the new Australian Curriculum, this issue the authors focus, on Geometry in the Measurement and Geometry strand with strong links for an integrated focus on the Statistics and Probability strand. The small unit of work on the sorting and…

  8. Linking Literacy and Movement

    ERIC Educational Resources Information Center

    Pica, Rae

    2010-01-01

    There are many links between literacy and movement. Movement and language are both forms of communication and self-expression. Rhythm is an essential component of both language and movement. While people may think of rhythm primarily in musical terms, there is a rhythm to words and sentences as well. Individuals develop an internal rhythm when…

  9. 76 FR 12220 - Petition for Exemption From the Federal Motor Vehicle Motor Theft Prevention Standard; Jaguar...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-03-04

    ... National Highway Traffic Safety Administration Petition for Exemption From the Federal Motor Vehicle Motor... on the line as standard equipment is likely to be as effective in reducing and deterring motor... deterring motor vehicle theft as compliance with ] the parts-marking requirements of the Theft...

  10. 76 FR 12221 - Petition for Exemption From the Federal Motor Vehicle Motor Theft Prevention Standard; Toyota

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-03-04

    ... National Highway Traffic Safety Administration Petition for Exemption From the Federal Motor Vehicle Motor... of Toyota Motor North America, Inc's., (Toyota) petition for an exemption of the Corolla vehicle line... equipment is likely to be as effective in reducing and deterring motor vehicle theft as compliance with...

  11. 78 FR 3081 - Petition for Exemption From the Federal Motor Vehicle Motor Theft Prevention Standard; Toyota

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-01-15

    ... National Highway Traffic Safety Administration Petition for Exemption From the Federal Motor Vehicle Motor... Transportation (DOT). ACTION: Grant of petition for exemption. SUMMARY: This document grants in full Toyota Motor... to be as effective in reducing and deterring motor vehicle theft as compliance with the...

  12. Descending motor pathways and the spinal motor system - Limbic and non-limbic components

    NASA Technical Reports Server (NTRS)

    Holstege, Gert

    1991-01-01

    Research on descending motor pathways to caudal brainstem and spinal cord in the spinal motor system is reviewed. Particular attention is given to somatic and autonomic motoneurons in the spinal cord and brainstem, local projections to motoneurons, bulbospinal interneurons projecting to motoneurons, descending pathways of somatic motor control systems, and descending pathways involved in limbic motor control systems.

  13. Assessment of Preschoolers' Gross Motor Proficiency: Revisiting Bruininks-Oseretsky Test of Motor Proficiency

    ERIC Educational Resources Information Center

    Lam, Hazel Mei Yung

    2011-01-01

    Literature reveals that there are very few validated motor proficiency tests for young children. According to Gallahue and Ozmun, the Bruininks-Oseretsky Test of Motor Proficiency is a valid test. However, manipulative skills, which are classified as gross motor skills by most motor development specialists, are only tested in the Upper Limb…

  14. FUZZY LOGIC CONTROL OF ELECTRIC MOTORS AND MOTOR DRIVES: FEASIBILITY STUDY

    EPA Science Inventory

    The report gives results of a study (part 1) of fuzzy logic motor control (FLMC). The study included: 1) reviews of existing applications of fuzzy logic, of motor operation, and of motor control; 2) a description of motor control schemes that can utilize FLMC; 3) selection of a m...

  15. 78 FR 66801 - Motor Carrier Safety Advisory Committee; Charter Renewal

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-11-06

    ... Federal Motor Carrier Safety Administration Motor Carrier Safety Advisory Committee; Charter Renewal AGENCY: Federal Motor Carrier Safety Administration (FMCSA), DOT. ACTION: Announcement of advisory... Committee that provides the Agency with advice and recommendations on motor carrier safety programs...

  16. Glutamate receptor antibodies in neurological diseases: anti-AMPA-GluR3 antibodies, anti-NMDA-NR1 antibodies, anti-NMDA-NR2A/B antibodies, anti-mGluR1 antibodies or anti-mGluR5 antibodies are present in subpopulations of patients with either: epilepsy, encephalitis, cerebellar ataxia, systemic lupus erythematosus (SLE) and neuropsychiatric SLE, Sjogren's syndrome, schizophrenia, mania or stroke. These autoimmune anti-glutamate receptor antibodies can bind neurons in few brain regions, activate glutamate receptors, decrease glutamate receptor's expression, impair glutamate-induced signaling and function, activate blood brain barrier endothelial cells, kill neurons, damage the brain, induce behavioral/psychiatric/cognitive abnormalities and ataxia in animal models, and can be removed or silenced in some patients by immunotherapy.

    PubMed

    Levite, Mia

    2014-08-01

    pathological effects: they activate glutamate/AMPA receptors, kill neurons by 'Excitotoxicity', and/or by complement activation modulated by complement regulatory proteins, cause multiple brain damage, aggravate chemoconvulsant-induced seizures, and also induce behavioral/motor impairments. Some patients with 'Autoimmune Epilepsy' that have anti-AMPA-GluR3B antibodies respond well (although sometimes transiently) to immunotherapy, and thanks to that have reduced seizures and overall improved neurological functions. (2) Anti-NMDA-NR1 antibodies are present in patients with autoimmune 'Anti-NMDA-receptor Encephalitis'. In humans, in animal models and in vitro the anti-NMDA-NR1 antibodies can be very pathogenic since they can cause a pronounced decrease of surface NMDA receptors expressed in hippocampal neurons, and also decrease the cluster density and synaptic localization of the NMDA receptors. The anti-NMDA-NR1 antibodies induce these effects by crosslinking and internalization of the NMDA receptors. Such changes can impair glutamate signaling via the NMDA receptors and lead to various neuronal/behavior/cognitive/psychiatric abnormalities. Anti-NMDA-NR1 antibodies are frequently present in high levels in the CSF of the patients with 'Anti-NMDA-receptor encephalitis' due to their intrathecal production. Many patients with 'Anti-NMDA receptor Encephalitis' respond well to several modes of immunotherapy. (3) Anti-NMDA-NR2A/B antibodies are present in a substantial number of patients with Systemic Lupus Erythematosus (SLE) with or without neuropsychiatric problems. The exact percentage of SLE patients having anti-NMDA-NR2A/B antibodies varies in different studies from 14 to 35%, and in one study such antibodies were found in 81% of patients with diffuse 'Neuropshychiatric SLE', and in 44% of patients with focal 'Neuropshychiatric SLE'. Anti-NMDA-NR2A/B antibodies are also present in subpopulations of patients with Epilepsy of several types, Encephalitis of several types (e

  17. An Operational Model of Motor Skill Diagnosis.

    ERIC Educational Resources Information Center

    Pinheiro, Victor E. D.; Simon, Herbert A.

    1992-01-01

    The ability to diagnose motor skills is important for physical educators. The paper discusses processes critical in motor skill diagnosis, proposing an operational model of motor skill development diagnosis for teacher educators and practitioners. The model provides a foundation upon which to build instructional strategies for developing…

  18. FUZZY LOGIC CONTROL OF AC INDUCTION MOTORS

    EPA Science Inventory

    The paper discusses the fuzzy logic control (FLC) of electric motors, being investigated under the sponsorship of the U.S. EPA to reduce energy consumption when motors are operated at less than rated speeds and loads. lectric motors use 60% of the electrical energy generated in t...

  19. Motor Acquisition Rate in Brazilian Infants

    ERIC Educational Resources Information Center

    Lopes, Virlaine Bardella; de Lima, Carolina Daniel; Tudella, Eloisa

    2009-01-01

    This study used the Alberta Infant Motor Scale (AIMS) with the aim of characterizing motor acquisition rate in 70 healthy 0-6-month-old Brazilian infants, as well as comparing both emergence (initial age) and establishment (final age) of each skill between the study sample and the AIMS normative data. New motor skills were continuously acquired…

  20. 33 CFR 159.69 - Motor ratings.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 33 Navigation and Navigable Waters 2 2011-07-01 2011-07-01 false Motor ratings. 159.69 Section 159.69 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) POLLUTION MARINE SANITATION DEVICES Design, Construction, and Testing § 159.69 Motor ratings. Motors must be...

  1. 33 CFR 127.1311 - Motor vehicles.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 33 Navigation and Navigable Waters 2 2010-07-01 2010-07-01 false Motor vehicles. 127.1311 Section... Waterfront Facilities Handling Liquefied Hazardous Gas Operations § 127.1311 Motor vehicles. (a) When LHG is... operator shall ensure that no person— (1) Stops or parks a motor vehicle in a space other than a...

  2. 33 CFR 127.1311 - Motor vehicles.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 33 Navigation and Navigable Waters 2 2013-07-01 2013-07-01 false Motor vehicles. 127.1311 Section... Waterfront Facilities Handling Liquefied Hazardous Gas Operations § 127.1311 Motor vehicles. (a) When LHG is... operator shall ensure that no person— (1) Stops or parks a motor vehicle in a space other than a...

  3. 33 CFR 159.69 - Motor ratings.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 33 Navigation and Navigable Waters 2 2012-07-01 2012-07-01 false Motor ratings. 159.69 Section 159.69 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) POLLUTION MARINE SANITATION DEVICES Design, Construction, and Testing § 159.69 Motor ratings. Motors must be...

  4. 47 CFR 32.2112 - Motor vehicles.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 47 Telecommunication 2 2011-10-01 2011-10-01 false Motor vehicles. 32.2112 Section 32.2112... FOR TELECOMMUNICATIONS COMPANIES Instructions for Balance Sheet Accounts § 32.2112 Motor vehicles. This account shall include the original cost of motor vehicles of the type which are designed...

  5. 33 CFR 159.69 - Motor ratings.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 33 Navigation and Navigable Waters 2 2013-07-01 2013-07-01 false Motor ratings. 159.69 Section 159.69 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) POLLUTION MARINE SANITATION DEVICES Design, Construction, and Testing § 159.69 Motor ratings. Motors must be...

  6. 47 CFR 32.2112 - Motor vehicles.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 47 Telecommunication 2 2013-10-01 2013-10-01 false Motor vehicles. 32.2112 Section 32.2112... FOR TELECOMMUNICATIONS COMPANIES Instructions for Balance Sheet Accounts § 32.2112 Motor vehicles. This account shall include the original cost of motor vehicles of the type which are designed...

  7. 47 CFR 32.2112 - Motor vehicles.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 47 Telecommunication 2 2014-10-01 2014-10-01 false Motor vehicles. 32.2112 Section 32.2112... FOR TELECOMMUNICATIONS COMPANIES Instructions for Balance Sheet Accounts § 32.2112 Motor vehicles. This account shall include the original cost of motor vehicles of the type which are designed...

  8. 33 CFR 127.1311 - Motor vehicles.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 33 Navigation and Navigable Waters 2 2014-07-01 2014-07-01 false Motor vehicles. 127.1311 Section... Waterfront Facilities Handling Liquefied Hazardous Gas Operations § 127.1311 Motor vehicles. (a) When LHG is... operator shall ensure that no person— (1) Stops or parks a motor vehicle in a space other than a...

  9. 33 CFR 127.1311 - Motor vehicles.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 33 Navigation and Navigable Waters 2 2012-07-01 2012-07-01 false Motor vehicles. 127.1311 Section... Waterfront Facilities Handling Liquefied Hazardous Gas Operations § 127.1311 Motor vehicles. (a) When LHG is... operator shall ensure that no person— (1) Stops or parks a motor vehicle in a space other than a...

  10. 33 CFR 159.69 - Motor ratings.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 33 Navigation and Navigable Waters 2 2014-07-01 2014-07-01 false Motor ratings. 159.69 Section 159.69 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) POLLUTION MARINE SANITATION DEVICES Design, Construction, and Testing § 159.69 Motor ratings. Motors must be...

  11. 47 CFR 32.2112 - Motor vehicles.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 47 Telecommunication 2 2012-10-01 2012-10-01 false Motor vehicles. 32.2112 Section 32.2112... FOR TELECOMMUNICATIONS COMPANIES Instructions for Balance Sheet Accounts § 32.2112 Motor vehicles. This account shall include the original cost of motor vehicles of the type which are designed...

  12. 33 CFR 159.69 - Motor ratings.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 33 Navigation and Navigable Waters 2 2010-07-01 2010-07-01 false Motor ratings. 159.69 Section 159.69 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) POLLUTION MARINE SANITATION DEVICES Design, Construction, and Testing § 159.69 Motor ratings. Motors must be...

  13. 33 CFR 127.1311 - Motor vehicles.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 33 Navigation and Navigable Waters 2 2011-07-01 2011-07-01 false Motor vehicles. 127.1311 Section... Waterfront Facilities Handling Liquefied Hazardous Gas Operations § 127.1311 Motor vehicles. (a) When LHG is... operator shall ensure that no person— (1) Stops or parks a motor vehicle in a space other than a...

  14. 47 CFR 32.2112 - Motor vehicles.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 47 Telecommunication 2 2010-10-01 2010-10-01 false Motor vehicles. 32.2112 Section 32.2112... FOR TELECOMMUNICATIONS COMPANIES Instructions for Balance Sheet Accounts § 32.2112 Motor vehicles. This account shall include the original cost of motor vehicles of the type which are designed...

  15. 30 CFR 18.34 - Motors.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Motors. 18.34 Section 18.34 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR TESTING, EVALUATION, AND APPROVAL OF MINING PRODUCTS ELECTRIC MOTOR-DRIVEN MINE EQUIPMENT AND ACCESSORIES Construction and Design Requirements § 18.34 Motors. Explosion-proof electric...

  16. Proceedings Region East Perceptual Motor Conference.

    ERIC Educational Resources Information Center

    American Alliance for Health, Physical Education, and Recreation, Washington, DC.

    This book of conference proceeding presents speeches and panel discussions from the Region East Perceptual-Motor Conference. The purpose of the conference was to seek an understanding of children and their perceptual-motor development through (a) exchange of knowledge and practices in perceptual-motor development, (b) examination of program…

  17. Save power in AC induction motors

    NASA Technical Reports Server (NTRS)

    Nola, F. J.

    1977-01-01

    Relatively simple and inexpensive circuitry improves power factor and reduces power dissipation in induction motors operating below full load. Electronic control loop conserves energy by reducing voltage applied to lightly loaded motor. Circuit forces motor to run at constant predetermined optimum power factor, regardless of load or line voltage variations. Solid-state switch varies voltage.

  18. Motor Development Programming in Trisomic-21 Babies

    ERIC Educational Resources Information Center

    Sanz, Teresa; Menendez, Javier; Rosique, Teresa

    2011-01-01

    The present study contributes to the understanding of gross motor development in babies with Down's syndrome. Also, it facilitates the comprehension of the efficiency of the early motor stimulation as well as of beginning it as early as possible. We worked with two groups of babies with Down's syndrome, beginning the early motor training in each…

  19. Motor Control: The Heart of Kinesiology

    ERIC Educational Resources Information Center

    Latash, Mark L.

    2008-01-01

    This brief review presents the subjective view of the author on the history of motor control and its current state among the subdisciplines of kinesiology. It summarizes the current controversies and challenges in motor control and emphasizes the necessity for an adequate set of notions that would make motor control (and kinesiology) a science.…

  20. Neuropsychological Investigation of Motor Impairments in Autism

    PubMed Central

    Duffield, Tyler; Trontel, Haley; Bigler, Erin D.; Froehlich, Alyson; Prigge, Molly B.; Travers, Brittany; Green, Ryan R.; Cariello, Annahir N.; Cooperrider, Jason; Nielsen, Jared; Alexander, Andrew; Anderson, Jeffrey; Fletcher, P. Thomas; Lange, Nicholas; Zielinski, Brandon; Lainhart, Janet

    2013-01-01

    It is unclear how standardized neuropsychological measures of motor function relate to brain volumes of motor regions in autism spectrum disorder (ASD). An all male sample composed of 59 ASD and 30 controls (ages 5–33 years) completed three measures of motor function: strength of grip (SOG), finger tapping test (FTT), and grooved peg-board test (GPT). Likewise, all participants underwent magnetic resonance imaging with region of interest (ROI) volumes obtained to include the following regions: motor cortex (pre-central gyrus), somatosensory cortex (post-central gyrus), thalamus, basal ganglia, cerebellum and caudal middle frontal gyrus. These traditional neuropsychological measures of motor function are assumed to differ in motor complexity with GPT requiring the most followed by FTT and SOG. Performance by ASD participants on the GPT and FTT differed significantly from controls, with the largest effect size differences observed on the more complex GPT task. Differences on the SOG task between the two groups were non-significant. Since more complex motor tasks tap more complex networks, poorer GPT performance by those with ASD may reflect less efficient motor networks. There was no gross pathology observed in classic motor areas of the brain in ASD, as region of interest (ROI) volumes did not differ, but FTT was negatively related to motor cortex volume in ASD. The results suggest a hierarchical motor disruption in ASD, with difficulties evident only in more complex tasks as well as a potential anomalous size-function relation in motor cortex in ASD. PMID:23985036

  1. Agricultural Electricity. Electric Motors. Student Manual.

    ERIC Educational Resources Information Center

    Benson, Robert T.

    Addressed to the student, this manual, which includes supplementary diagrams, discusses the following topics and principles: Electromagnetic fields, electromagnets, parts of an electric motor, determining speed of an electric motor, types of electric motors in common use (split-phase, capacitor, repulsion-induction, three-phase), the electric…

  2. Transcranial direct current stimulation of the motor cortex in waking resting state induces motor imagery.

    PubMed

    Speth, Jana; Speth, Clemens; Harley, Trevor A

    2015-11-01

    This study investigates if anodal and cathodal transcranial direct current stimulation (tDCS) of areas above the motor cortex (C3) influences spontaneous motor imagery experienced in the waking resting state. A randomized triple-blinded design was used, combining neurophysiological techniques with tools of quantitative mentation report analysis from cognitive linguistics. The results indicate that while spontaneous motor imagery rarely occurs under sham stimulation, general and athletic motor imagery (classified as athletic disciplines), is induced by anodal tDCS. This insight may have implications beyond basic consciousness research. Motor imagery and corresponding motor cortical activation have been shown to benefit later motor performance. Electrophysiological manipulations of motor imagery could in the long run be used for rehabilitative tDCS protocols benefitting temporarily immobile clinical patients who cannot perform specific motor imagery tasks - such as dementia patients, infants with developmental and motor disorders, and coma patients. PMID:26204566

  3. Modeling and control of a hydraulically actuated flexible-prismatic link robot

    SciTech Connect

    Love, L.; Kress, R.; Jansen, J.

    1996-12-01

    Most of the research related to flexible link manipulators to date has focused on single link, fixed length, single plane of vibration test beds. In addition, actuation has been predominantly based upon electromagnetic motors. Ironically, these elements are rarely found in the existing industrial long reach systems. This manuscript describes a new hydraulically actuated, long reach manipulator with a flexible prismatic link at Oak Ridge National Laboratory (ORNL). Focus is directed towards both modeling and control of hydraulic actuators as well as flexible links that have variable natural frequencies.

  4. Stepper motor control that adjusts to motor loading

    NASA Technical Reports Server (NTRS)

    Howard, David E. (Inventor); Nola, Frank J. (Inventor)

    2000-01-01

    A system and method are provided for controlling a stepper motor having a rotor and a multi-phase stator. Sinusoidal command signals define a commanded position of the motor's rotor. An actual position of the rotor is sensed as a function of an electrical angle between the actual position and the commanded position. The actual position is defined by sinusoidal position signals. An adjustment signal is generated using the sinusoidal command signals and sinusoidal position signals. The adjustment signal is defined as a function of the cosine of the electrical angle. The adjustment signal is multiplied by each sinusoidal command signal to generate a corresponding set of excitation signals, each of which is applied to a corresponding phase of the multi-phase stator.

  5. Keeping an eye on the violinist: motor experts show superior timing consistency in a visual perception task

    PubMed Central

    Cañal-Bruland, Rouwen

    2010-01-01

    Common coding theory states that perception and action may reciprocally induce each other. Consequently, motor expertise should map onto perceptual consistency in specific tasks such as predicting the exact timing of a musical entry. To test this hypothesis, ten string musicians (motor experts), ten non-string musicians (visual experts), and ten non-musicians were asked to watch progressively occluded video recordings of a first violinist indicating entries to fellow members of a string quartet. Participants synchronised with the perceived timing of the musical entries. Results revealed significant effects of motor expertise on perception. Compared to visual experts and non-musicians, string players not only responded more accurately, but also with less timing variability. These findings provide evidence that motor experts’ consistency in movement execution—a key characteristic of expert motor performance—is mirrored in lower variability in perceptual judgements, indicating close links between action competence and perception. PMID:20300943

  6. Method and apparatus for monitoring motor operated valve motor output torque and power at valve seating

    SciTech Connect

    Casada, Donald A.

    1996-01-01

    A method and apparatus are provided for monitoring a motor operated valve during the brief period when the valve seats and the torque switch trips to deenergize the valve motor. The method uses voltage measurements on the load side of a deenergizing switch that opens to deenergize the motor to determine, among other things, final motor rotational speed and the decelerating torque at motor deenergization.

  7. Method and apparatus for monitoring motor operated valve motor output torque and power at valve seating

    SciTech Connect

    Casada, D.A.

    1996-01-16

    A method and apparatus are provided for monitoring a motor operated valve during the brief period when the valve seats and the torque switch trips to deenergize the valve motor. The method uses voltage measurements on the load side of a deenergizing switch that opens to deenergize the motor to determine, among other things, final motor rotational speed and the decelerating torque at motor deenergization. 14 figs.

  8. Motor deficits correlate with resting state motor network connectivity in patients with brain tumours

    PubMed Central

    Mikell, Charles B.; Youngerman, Brett E.; Liston, Conor; Sisti, Michael B.; Bruce, Jeffrey N.; Small, Scott A.; McKhann, Guy M.

    2012-01-01

    While a tumour in or abutting primary motor cortex leads to motor weakness, how tumours elsewhere in the frontal or parietal lobes affect functional connectivity in a weak patient is less clear. We hypothesized that diminished functional connectivity in a distributed network of motor centres would correlate with motor weakness in subjects with brain masses. Furthermore, we hypothesized that interhemispheric connections would be most vulnerable to subtle disruptions in functional connectivity. We used task-free functional magnetic resonance imaging connectivity to probe motor networks in control subjects and patients with brain tumours (n = 22). Using a control dataset, we developed a method for automated detection of key nodes in the motor network, including the primary motor cortex, supplementary motor area, premotor area and superior parietal lobule, based on the anatomic location of the hand-motor knob in the primary motor cortex. We then calculated functional connectivity between motor network nodes in control subjects, as well as patients with and without brain masses. We used this information to construct weighted, undirected graphs, which were then compared to variables of interest, including performance on a motor task, the grooved pegboard. Strong connectivity was observed within the identified motor networks between all nodes bilaterally, and especially between the primary motor cortex and supplementary motor area. Reduced connectivity was observed in subjects with motor weakness versus subjects with normal strength (P < 0.001). This difference was driven mostly by decreases in interhemispheric connectivity between the primary motor cortices (P < 0.05) and between the left primary motor cortex and the right premotor area (P < 0.05), as well as other premotor area connections. In the subjects without motor weakness, however, performance on the grooved pegboard did not relate to interhemispheric connectivity, but rather was inversely

  9. AUTOMOTIVE DIESEL MAINTENANCE 2. UNIT XIX, LEARNING ABOUT CRANKING MOTORS.

    ERIC Educational Resources Information Center

    Human Engineering Inst., Cleveland, OH.

    THIS MODULE OF A 25-MODULE COURSE IS DESIGNED TO DEVELOP AN UNDERSTANDING OF THE OPERATING PRINCIPLES OF CRANKING MOTORS USED ON DIESEL POWERED EQUIPMENT, TOPICS ARE (1) CRANKING MOTORS. (2) MOTOR PINCIPLES, (3) CRANKING MOTOR CIRCUITS, (4) TYPES OF CRANKING MOTOR DRIVES, AND (5) CRANKING MOTOR SOLENOID CIRCUITS. THE MODULE CONSISTS OF A…

  10. Surround inhibition in motor execution and motor imagery.

    PubMed

    Aoyama, Toshiyuki; Kaneko, Fuminari; Ohashi, Yukari; Nagata, Hiroshi

    2016-08-26

    Surround inhibition (SI) is a neural mechanism to focus neuronal activity and facilitate selective motor execution (ME). The aim of the present study was to investigate whether SI is also generated during motor imagery (MI). Furthermore, we investigated whether the extent of SI during MI depends on the strength of SI during ME and/or vividness of MI. The extent of SI was examined during MI and ME of index finger flexion. Transcranial magnetic stimulation was applied at rest, during initiation of the movement (phasic phase) and during tonic muscle contraction of the index finger flexors. Motor evoked potentials (MEPs) were recorded from a surround muscle, abductor digiti minimi (ADM) and a synergistic muscle, the first dorsal interosseous muscle. The amplitude of ADM MEP was reduced during the phasic phase, which indicates that SI occurred during ME. In seven of 14 subjects, SI was also observed during MI, although this effect was not significant. There was a moderate correlation between the extent of SI during ME and MI. Furthermore, good imagers who experienced vivid MI during the MI task showed stronger SI than poor imagers. These results indicate that common neural substrates involved in SI during ME are at least in part recruited during MI. In clinical situations, the therapeutic use of MI to generate vivid MI may be one of effective tool to develop the strength of SI, which facilitate selective execution of desired movements. PMID:27418120

  11. Non-motor symptoms in Parkinson's disease.

    PubMed

    Pfeiffer, Ronald F

    2016-01-01

    With the growing awareness of the presence of non-motor symptoms in Parkinson's disease (PD) has come the realization that these non-motor features play a tremendously important, and sometimes dominant, role in the management and even the diagnosis of the disorder. Despite this, a reluctance to formally address and treat the non-motor symptoms of PD remains and quality of life for PD patients suffers. This review provides an overview of the impact non-motor symptoms have on persons with PD, along with a brief description of some of the more common non-motor features of PD. PMID:26372623

  12. Functional improvement after motor training is correlated with synaptic plasticity in rat thalamus.

    PubMed

    Ding, Yuchuan; Li, Jie; Lai, Qin; Azam, Salman; Rafols, José A; Diaz, Fernando G

    2002-12-01

    The goals of this study were to determine whether functional outcome after motor training in rats was linked to synaptic plasticity in thalamus, and whether the Rota-rod apparatus, widely used to test motor function, could be used as an easy and quantitative motor skill training procedure. Adult female Sprague-Dawley rats (n = 39) were evaluated under three training conditions: 1. Movement requiring balance and coordination skills on Rota-rod; 2. simple exercise on treadmill; 3. nontrained controls. Motor function was evaluated by a series of motor tests (foot fault placing, parallel bar crossing, rope and ladder climbing) before and 14 or 28 days after training procedure. Synaptic strength in brain was assessed by synaptophysin immunocytochemistry. After 14 days of training, Rota-rod-trained animals significantly (p < 0.01) improved motor performance, compared to treadmill and nontrained animals. Animals with up to 28 days of simple exercises on the treadmill did not show a significantly improved performance on most motor tasks, except for an improvement in foot fault placing. Intensive synaptophysin immunoreactivity was present in the right but not the left mediodorsal and ventromedial nuclei of thalamus in Rota-rod-trained rats at 14 and 28 days, and in treadmill-trained rats at 28 days. The data suggested that functional outcome is effectively improved by motor skill training rather than by simple exercises, and this may be related, at least partially, to uniquely lateralized synaptogenesis in the thalamus. Both Rota-rod and treadmill could be quantitatively used in rats for motor training of different complexity. PMID:12500709

  13. Cerebellar contributions to visuomotor adaptation and motor sequence learning: an ALE meta-analysis

    PubMed Central

    Bernard, Jessica A.; Seidler, Rachael D.

    2013-01-01

    Cerebellar contributions to motor learning are well-documented. For example, under some conditions, patients with cerebellar damage are impaired at visuomotor adaptation and at acquiring new action sequences. Moreover, cerebellar activation has been observed in functional MRI (fMRI) investigations of various motor learning tasks. The early phases of motor learning are cognitively demanding, relying on processes such as working memory, which have been linked to the cerebellum as well. Here, we investigated cerebellar contributions to motor learning using activation likelihood estimation (ALE) meta-analysis. This allowed us to determine, across studies and tasks, whether or not the location of cerebellar activation is constant across differing motor learning tasks, and whether or not cerebellar activation in early learning overlaps with that observed for working memory. We found that different regions of the anterior cerebellum are engaged for implicit and explicit sequence learning and visuomotor adaptation, providing additional evidence for the modularity of cerebellar function. Furthermore, we found that lobule VI of the cerebellum, which has been implicated in working memory, is activated during the early stages of explicit motor sequence learning. This provides evidence for a potential role for the cerebellum in the cognitive processing associated with motor learning. However, though lobule VI was activated across both early explicit sequence learning and working memory studies, there was no spatial overlap between these two regions. Together, our results support the idea of modularity in the formation of internal representations of new motor tasks in the cerebellum, and highlight the cognitive processing relied upon during the early phases of motor skill learning. PMID:23403800

  14. High stability radio links

    NASA Technical Reports Server (NTRS)

    Kursinski, E. Robert

    1989-01-01

    Radio telecommunication links are used for communication with deep space probes. These links consist of sinusoidal carrier signals at radio frequencies (RF) modulated with information sent between the spacecraft and the earth. This carrier signal is a very pure and stable sinusoid, typically derived from an atomic frequency standard whose frequency and phase are used to measure the radial velocity of the probe and from this and other data types derive its trajectory. This same observable can be used to search for space-time distortions cased by low frequency (0.1 to 100 MHz) gravitation radiation. How such a system works, what its sensitivity limitations are, and what potential future improvements can be made are discussed.

  15. The missing link.

    PubMed

    Dracup, Kathleen

    2002-06-01

    The uniqueness of nursing research is derived from the philosophical view of the individual as a biopsychosocial being. Nurse scientists are prepared to illuminate the linkages among the biophysiological, psychological, and social domains, and this study is much enhanced by the increasing availability of valid and reliable biomarkers. Researchers need to develop expertise in the use of biomarkers and secure appropriate funding for their use. Missing links may be missing no longer. PMID:12122766

  16. Cerebellar Motor Function in Spina Bifida Meningomyelocele

    PubMed Central

    Dennis, Maureen; Salman, Michael S.; Juranek, Jenifer; Fletcher, Jack M.

    2010-01-01

    Spina bifida meningomyelocele (SBM), a congenital neurodevelopmental disorder, involves dysmorphology of the cerebellum, and its most obvious manifestations are motor deficits. This paper reviews cerebellar neuropathology and motor function across several motor systems well studied in SBM in relation to current models of cerebellar motor and timing function. Children and adults with SBM have widespread motor deficits in trunk, upper limbs, eyes, and speech articulators that are broadly congruent with those observed in adults with cerebellar lesions. The structure and function of the cerebellum are correlated with a range of motor functions. While motor learning is generally preserved in SBM, those motor functions requiring predictive signals and precise calibration of the temporal features of movement are impaired, resulting in deficits in smooth movement coordination as well as in the classical cerebellar triad of dysmetria, ataxia, and dysarthria. That motor function in individuals with SBM is disordered in a manner phenotypically similar to that in adult cerebellar lesions, and appears to involve similar deficits in predictive cerebellar motor control, suggests that age-based cerebellar motor plasticity is limited in individuals with this neurodevelopmental disorder. PMID:20652468

  17. Bearingless Segment Motor with Buried Magnets

    NASA Astrophysics Data System (ADS)

    Gruber, Wolfgang; Amrhein, Wolfgang; Stallinger, Thomas; Grabner, Herbert

    Bearingless motors combine contactless levitation and rotation in a preferably compact system design, because bearing as well as motor windings are located on the same lamination stack. The bearingless slice motor features comparatively low complexity for a fully magnetically levitated drive system, because it allows the passive stabilization of three degrees of freedom by reluctance forces. By the use of a proper control scheme and the superposition of different current components, bearing forces and motor torque can be generated simultaneously by applying concentrated windings. This leads to a further simplification of the mechanical configuration. The bearingless segment motor features such concentrated coils on separated stator elements, which reduce the stator iron and therefore weight and cost, especially for constructions with large diameter. However, so far all bearingless slice motors are designed with surface mounted permanent magnets on the rotor, neglecting the advantages of buried permanent magnets. In this paper a novel bearingless segment motor featuring a rotor with buried permanent magnets is investigated. The motor specific mathematical model of force and torque generation is presented, a proper control scheme is introduced and the optimization of the prototype motor is outlined. Motor specific considerations concerning the angular sensors are given. Finally, the performance of the bearingless segment motor with buried permanent magnets is shown by the comparison of simulation results with measurement data of the manufactured prototype.

  18. Analysis of HB Type Vernier Motor

    NASA Astrophysics Data System (ADS)

    Suda, Hiroshi; Matsushima, Yoshitaro; Xu, Li; Anazawa, Yoshihisa

    Direct drive motors are used as actuators in numerous applications in which they must rotate at low speeds with high torque and low torque ripple. Recently, various types of vernier motor have been developed. The HB type vernier motor is one of them. The structure of rotor is the same as HB type stepping motor. Our model of HB type vernier motor has a winding as field system in the rotor, but stator has three-phase windings. Relationship between S, R and P is S ± P/2=R/2, where S, R and P are the numbers of stator and rotor slots and the number of poles. The rotor of the vernier motor moves at a sub-multiple of the angular velocity of the stator mmf. The multiplying factor is P/R. As a result of analysis, the voltage equation on the γ-δ axis of HB type vernier motor is equal to general synchronous machine. The tests were performed on the trial motor. The calculated pull-out torque agreed well with the measured values. Our model of HB type vernier motor is equivalent with the PM type vernier motor which has permanent magnets in the rotor. The result of this analysis is useful for the design of both types of vernier motor.

  19. Molecular Motors: Power Strokes Outperform Brownian Ratchets.

    PubMed

    Wagoner, Jason A; Dill, Ken A

    2016-07-01

    Molecular motors convert chemical energy (typically from ATP hydrolysis) to directed motion and mechanical work. Their actions are often described in terms of "Power Stroke" (PS) and "Brownian Ratchet" (BR) mechanisms. Here, we use a transition-state model and stochastic thermodynamics to describe a range of mechanisms ranging from PS to BR. We incorporate this model into Hill's diagrammatic method to develop a comprehensive model of motor processivity that is simple but sufficiently general to capture the full range of behavior observed for molecular motors. We demonstrate that, under all conditions, PS motors are faster, more powerful, and more efficient at constant velocity than BR motors. We show that these differences are very large for simple motors but become inconsequential for complex motors with additional kinetic barrier steps. PMID:27136319

  20. Method and apparatus for controlling multiple motors

    DOEpatents

    Jones, Rollin G.; Kortegaard, Bert L.; Jones, David F.

    1987-01-01

    A method and apparatus are provided for simultaneously controlling a plurality of stepper motors. Addressing circuitry generates address data for each motor in a periodic address sequence. Memory circuits respond to the address data for each motor by accessing a corresponding memory location containing a first operational data set functionally related to a direction for moving the motor, speed data, and rate of speed change. First logic circuits respond to the first data set to generate a motor step command. Second logic circuits respond to the command from the first logic circuits to generate a third data set for replacing the first data set in memory with a current operational motor status, which becomes the first data set when the motor is next addressed.