The Experts below are selected from a list of 216 Experts worldwide ranked by ideXlab platform
Silvia Arber - One of the best experts on this subject based on the ideXlab platform.
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Brainstem nucleus MdV mediates skilled forelimb motor tasks
Nature, 2014Co-Authors: Maria Soledad Esposito, Paolo Capelli, Silvia ArberAbstract:Brainstem circuits controlling precision movementTwo papers published in this issue of Nature address a long-standing puzzle in mammalian motor control — the organization and function of circuits between the brain and spinal cord that control motor movements such as reaching. Thomas Jessell and colleagues investigate a class of mouse spinal interneurons known in other species to be involved in fine forelimb movements. They show that in mouse, these neurons have appropriate anatomical innervation to carry both motor commands and an internal copy signal, and ablation of these neurons impairs reaching movements. Furthermore, optogenetic activation of the ascending branch recruits a cerebellar circuit, and also disrupts reaching movements. These findings implicate these neurons as part of an internal copy pathway for rapid updating of motor output during reaching. Silvia Arber and colleagues use a combination of viral tracing and genetics to characterize the diversity of neurons projecting from mouse brainstem to motor neurons that control limb movements. They discover that one region in particular, the ventral medullary reticular formation or MdV, is functionally specialized for forelimb motor control. Neurons here specifically target forelimb neurons and are recruited during motor tasks, and inactivation of these neurons impairs fine movements.AbstractTranslating the behavioural output of the nervous System into movement involves interaction between brain and spinal cord. The brainstem provides an essential bridge between the two structures, but circuit-level organization and function of this Intermediary System remain poorly understood. Here we use intersectional virus tracing and genetic strategies in mice to reveal a selective synaptic connectivity matrix between brainstem substructures and functionally distinct spinal motor neurons that regulate limb movement. The brainstem nucleus medullary reticular formation ventral part (MdV) stands out as specifically targeting subpopulations of forelimb-innervating motor neurons. Its glutamatergic premotor neurons receive synaptic input from key upper motor centres and are recruited during motor tasks. Selective neuronal ablation or silencing experiments reveal that MdV is critically important specifically for skilled motor behaviour, including accelerating rotarod and single-food-pellet reaching tasks. Our results indicate that distinct premotor brainstem nuclei access spinal subcircuits to mediate task-specific aspects of motor programs.The authors use a combination of viral tracing and genetics to characterize the diversity of neurons projecting from mouse brainstem to motor neurons that control limb movements; in particular they discover that the medullary reticular formation ventral part (MdV) is functionally specialized for skilled forelimb motor control.
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Brainstem nucleus MdV mediates skilled forelimb motor tasks
Nature, 2014Co-Authors: Maria Soledad Esposito, Paolo Capelli, Silvia ArberAbstract:Two papers published in this issue of Nature address a long-standing puzzle in mammalian motor control — the organization and function of circuits between the brain and spinal cord that control motor movements such as reaching. Thomas Jessell and colleagues investigate a class of mouse spinal interneurons known in other species to be involved in fine forelimb movements. They show that in mouse, these neurons have appropriate anatomical innervation to carry both motor commands and an internal copy signal, and ablation of these neurons impairs reaching movements. Furthermore, optogenetic activation of the ascending branch recruits a cerebellar circuit, and also disrupts reaching movements. These findings implicate these neurons as part of an internal copy pathway for rapid updating of motor output during reaching. Silvia Arber and colleagues use a combination of viral tracing and genetics to characterize the diversity of neurons projecting from mouse brainstem to motor neurons that control limb movements. They discover that one region in particular, the ventral medullary reticular formation or MdV, is functionally specialized for forelimb motor control. Neurons here specifically target forelimb neurons and are recruited during motor tasks, and inactivation of these neurons impairs fine movements. Translating the behavioural output of the nervous System into movement involves interaction between brain and spinal cord. The brainstem provides an essential bridge between the two structures, but circuit-level organization and function of this Intermediary System remain poorly understood. Here we use intersectional virus tracing and genetic strategies in mice to reveal a selective synaptic connectivity matrix between brainstem substructures and functionally distinct spinal motor neurons that regulate limb movement. The brainstem nucleus medullary reticular formation ventral part (MdV) stands out as specifically targeting subpopulations of forelimb-innervating motor neurons. Its glutamatergic premotor neurons receive synaptic input from key upper motor centres and are recruited during motor tasks. Selective neuronal ablation or silencing experiments reveal that MdV is critically important specifically for skilled motor behaviour, including accelerating rotarod and single-food-pellet reaching tasks. Our results indicate that distinct premotor brainstem nuclei access spinal subcircuits to mediate task-specific aspects of motor programs. The authors use a combination of viral tracing and genetics to characterize the diversity of neurons projecting from mouse brainstem to motor neurons that control limb movements; in particular they discover that the medullary reticular formation ventral part (MdV) is functionally specialized for skilled forelimb motor control.
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Brainstem nucleus MdV mediates skilled forelimb motor tasks
Nature, 2014Co-Authors: Maria Soledad Esposito, Paolo Capelli, Silvia ArberAbstract:Translating the behavioural output of the nervous System into movement involves interaction between brain and spinal cord. The brainstem provides an essential bridge between the two structures, but circuit-level organization and function of this Intermediary System remain poorly understood. Here we use intersectional virus tracing and genetic strategies in mice to reveal a selective synaptic connectivity matrix between brainstem substructures and functionally distinct spinal motor neurons that regulate limb movement. The brainstem nucleus medullary reticular formation ventral part (MdV) stands out as specifically targeting subpopulations of forelimb-innervating motor neurons. Its glutamatergic premotor neurons receive synaptic input from key upper motor centres and are recruited during motor tasks. Selective neuronal ablation or silencing experiments reveal that MdV is critically important specifically for skilled motor behaviour, including accelerating rotarod and single-food-pellet reaching tasks. Our results indicate that distinct premotor brainstem nuclei access spinal subcircuits to mediate task-specific aspects of motor programs.
Maria Soledad Esposito - One of the best experts on this subject based on the ideXlab platform.
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Brainstem nucleus MdV mediates skilled forelimb motor tasks
Nature, 2014Co-Authors: Maria Soledad Esposito, Paolo Capelli, Silvia ArberAbstract:Brainstem circuits controlling precision movementTwo papers published in this issue of Nature address a long-standing puzzle in mammalian motor control — the organization and function of circuits between the brain and spinal cord that control motor movements such as reaching. Thomas Jessell and colleagues investigate a class of mouse spinal interneurons known in other species to be involved in fine forelimb movements. They show that in mouse, these neurons have appropriate anatomical innervation to carry both motor commands and an internal copy signal, and ablation of these neurons impairs reaching movements. Furthermore, optogenetic activation of the ascending branch recruits a cerebellar circuit, and also disrupts reaching movements. These findings implicate these neurons as part of an internal copy pathway for rapid updating of motor output during reaching. Silvia Arber and colleagues use a combination of viral tracing and genetics to characterize the diversity of neurons projecting from mouse brainstem to motor neurons that control limb movements. They discover that one region in particular, the ventral medullary reticular formation or MdV, is functionally specialized for forelimb motor control. Neurons here specifically target forelimb neurons and are recruited during motor tasks, and inactivation of these neurons impairs fine movements.AbstractTranslating the behavioural output of the nervous System into movement involves interaction between brain and spinal cord. The brainstem provides an essential bridge between the two structures, but circuit-level organization and function of this Intermediary System remain poorly understood. Here we use intersectional virus tracing and genetic strategies in mice to reveal a selective synaptic connectivity matrix between brainstem substructures and functionally distinct spinal motor neurons that regulate limb movement. The brainstem nucleus medullary reticular formation ventral part (MdV) stands out as specifically targeting subpopulations of forelimb-innervating motor neurons. Its glutamatergic premotor neurons receive synaptic input from key upper motor centres and are recruited during motor tasks. Selective neuronal ablation or silencing experiments reveal that MdV is critically important specifically for skilled motor behaviour, including accelerating rotarod and single-food-pellet reaching tasks. Our results indicate that distinct premotor brainstem nuclei access spinal subcircuits to mediate task-specific aspects of motor programs.The authors use a combination of viral tracing and genetics to characterize the diversity of neurons projecting from mouse brainstem to motor neurons that control limb movements; in particular they discover that the medullary reticular formation ventral part (MdV) is functionally specialized for skilled forelimb motor control.
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Brainstem nucleus MdV mediates skilled forelimb motor tasks
Nature, 2014Co-Authors: Maria Soledad Esposito, Paolo Capelli, Silvia ArberAbstract:Two papers published in this issue of Nature address a long-standing puzzle in mammalian motor control — the organization and function of circuits between the brain and spinal cord that control motor movements such as reaching. Thomas Jessell and colleagues investigate a class of mouse spinal interneurons known in other species to be involved in fine forelimb movements. They show that in mouse, these neurons have appropriate anatomical innervation to carry both motor commands and an internal copy signal, and ablation of these neurons impairs reaching movements. Furthermore, optogenetic activation of the ascending branch recruits a cerebellar circuit, and also disrupts reaching movements. These findings implicate these neurons as part of an internal copy pathway for rapid updating of motor output during reaching. Silvia Arber and colleagues use a combination of viral tracing and genetics to characterize the diversity of neurons projecting from mouse brainstem to motor neurons that control limb movements. They discover that one region in particular, the ventral medullary reticular formation or MdV, is functionally specialized for forelimb motor control. Neurons here specifically target forelimb neurons and are recruited during motor tasks, and inactivation of these neurons impairs fine movements. Translating the behavioural output of the nervous System into movement involves interaction between brain and spinal cord. The brainstem provides an essential bridge between the two structures, but circuit-level organization and function of this Intermediary System remain poorly understood. Here we use intersectional virus tracing and genetic strategies in mice to reveal a selective synaptic connectivity matrix between brainstem substructures and functionally distinct spinal motor neurons that regulate limb movement. The brainstem nucleus medullary reticular formation ventral part (MdV) stands out as specifically targeting subpopulations of forelimb-innervating motor neurons. Its glutamatergic premotor neurons receive synaptic input from key upper motor centres and are recruited during motor tasks. Selective neuronal ablation or silencing experiments reveal that MdV is critically important specifically for skilled motor behaviour, including accelerating rotarod and single-food-pellet reaching tasks. Our results indicate that distinct premotor brainstem nuclei access spinal subcircuits to mediate task-specific aspects of motor programs. The authors use a combination of viral tracing and genetics to characterize the diversity of neurons projecting from mouse brainstem to motor neurons that control limb movements; in particular they discover that the medullary reticular formation ventral part (MdV) is functionally specialized for skilled forelimb motor control.
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Brainstem nucleus MdV mediates skilled forelimb motor tasks
Nature, 2014Co-Authors: Maria Soledad Esposito, Paolo Capelli, Silvia ArberAbstract:Translating the behavioural output of the nervous System into movement involves interaction between brain and spinal cord. The brainstem provides an essential bridge between the two structures, but circuit-level organization and function of this Intermediary System remain poorly understood. Here we use intersectional virus tracing and genetic strategies in mice to reveal a selective synaptic connectivity matrix between brainstem substructures and functionally distinct spinal motor neurons that regulate limb movement. The brainstem nucleus medullary reticular formation ventral part (MdV) stands out as specifically targeting subpopulations of forelimb-innervating motor neurons. Its glutamatergic premotor neurons receive synaptic input from key upper motor centres and are recruited during motor tasks. Selective neuronal ablation or silencing experiments reveal that MdV is critically important specifically for skilled motor behaviour, including accelerating rotarod and single-food-pellet reaching tasks. Our results indicate that distinct premotor brainstem nuclei access spinal subcircuits to mediate task-specific aspects of motor programs.
Lieven M. K. Vandersypen - One of the best experts on this subject based on the ideXlab platform.
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Coherent spin-exchange via a quantum mediator
Nature Nanotechnology, 2017Co-Authors: T. A. Baart, Takafumi Fujita, Christian Reichl, Werner Wegscheider, Lieven M. K. VandersypenAbstract:Two electron spins occupying the outer dots in a linear array of three quantum dots experience a coherent superexchange interaction through the empty middle dot that acts as a quantum mediator. Coherent interactions at a distance provide a powerful tool for quantum simulation and computation. The most common approach to realize an effective long-distance coupling ‘on-chip’ is to use a quantum mediator, as has been demonstrated for superconducting qubits^ 1 , 2 and trapped ions^ 3 . For quantum dot arrays, which combine a high degree of tunability^ 4 with extremely long coherence times^ 5 , the experimental demonstration of the time evolution of coherent spin–spin coupling via an Intermediary System remains an important outstanding goal^ 6 , 7 , 8 , 9 , 10 , 11 , 12 , 13 , 14 , 15 , 16 , 17 , 18 , 19 , 20 , 21 , 22 , 23 , 24 , 25 . Here, we use a linear triple-quantum-dot array to demonstrate a coherent time evolution of two interacting distant spins via a quantum mediator. The two outer dots are occupied with a single electron spin each, and the spins experience a superexchange interaction through the empty middle dot, which acts as mediator. Using single-shot spin readout^ 26 , we measure the coherent time evolution of the spin states on the outer dots and observe a characteristic dependence of the exchange frequency as a function of the detuning between the middle and outer dots. This approach may provide a new route for scaling up spin qubit circuits using quantum dots, and aid in the simulation of materials and molecules with non-nearest-neighbour couplings such as MnO (ref. 27 ), high-temperature superconductors^ 28 and DNA^ 29 . The same superexchange concept can also be applied in cold atom experiments^ 30 .
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Coherent spin-exchange via a quantum mediator
Nature nanotechnology, 2016Co-Authors: T. A. Baart, Takafumi Fujita, Christian Reichl, Werner Wegscheider, Lieven M. K. VandersypenAbstract:Coherent interactions at a distance provide a powerful tool for quantum simulation and computation. The most common approach to realize an effective long-distance coupling 'on-chip' is to use a quantum mediator, as has been demonstrated for superconducting qubits and trapped ions. For quantum dot arrays, which combine a high degree of tunability with extremely long coherence times, the experimental demonstration of the time evolution of coherent spin-spin coupling via an Intermediary System remains an important outstanding goal. Here, we use a linear triple-quantum-dot array to demonstrate a coherent time evolution of two interacting distant spins via a quantum mediator. The two outer dots are occupied with a single electron spin each, and the spins experience a superexchange interaction through the empty middle dot, which acts as mediator. Using single-shot spin readout, we measure the coherent time evolution of the spin states on the outer dots and observe a characteristic dependence of the exchange frequency as a function of the detuning between the middle and outer dots. This approach may provide a new route for scaling up spin qubit circuits using quantum dots, and aid in the simulation of materials and molecules with non-nearest-neighbour couplings such as MnO (ref. 27), high-temperature superconductors and DNA. The same superexchange concept can also be applied in cold atom experiments.
Chihiro Watanabe - One of the best experts on this subject based on the ideXlab platform.
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TOWARDS AN INSTITUTIONS-THEORETIC FRAMEWORK COMPARING SOLAR PHOTOVOLTAIC DIFFUSION PATTERNS IN JAPAN AND THE UNITED STATES
International Journal of Innovation Management, 2007Co-Authors: Kwok L. Shum, Chihiro WatanabeAbstract:This paper studies and compares the actual historic solar photovoltaic (PV) installation data in Japan and the United States and proposes two deployment models to account for the differences. Deployment, along with research, development and demonstration, constitutes what is known as the RD3 (PCAST — President's Council of Advances in Science and Technology, United States) innovative chain of a new technology. Japan deploys PV focusing on the niche of utility grid-tied small-scale System (90 per cent of which is standardised roof-top residential PV System) using highly integrated value chain; this seems to draw upon her strong manufacturing culture and associated social technology and institutions for suppliers-dominated innovations. The United States deploys PV as a broadly defined innovation emphasising user-oriented customisation in both on and off grid, residential and industrial applications using small independent and Intermediary System integrators. Empirical analysis of the diffusion patterns in t...
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TOWARDS AN INSTITUTIONS-THEORETIC FRAMEWORK COMPARING SOLAR PHOTOVOLTAIC DIFFUSION PATTERNS IN JAPAN AND THE UNITED STATES
International Journal of Innovation Management, 2007Co-Authors: Kwok L. Shum, Chihiro WatanabeAbstract:This paper studies and compares the actual historic solar photovoltaic (PV) installation data in Japan and the United States and proposes two deployment models to account for the differences. Deployment, along with research, development and demonstration, constitutes what is known as the RD3 (PCAST — President's Council of Advances in Science and Technology, United States) innovative chain of a new technology. Japan deploys PV focusing on the niche of utility grid-tied small-scale System (90 per cent of which is standardised roof-top residential PV System) using highly integrated value chain; this seems to draw upon her strong manufacturing culture and associated social technology and institutions for suppliers-dominated innovations. The United States deploys PV as a broadly defined innovation emphasising user-oriented customisation in both on and off grid, residential and industrial applications using small independent and Intermediary System integrators. Empirical analysis of the diffusion patterns in the grid-tied small System category in respective contexts suggests that Japan's institutions seem to match her mass deployment strategy while the United States' combination of fragmented industry structure and diversity deployment gives rise to a complex diffusion pattern calling for continual institutional innovation or co-evolution. Our research, therefore, highlights that commercialisation of new technology or technical change, in general, is not an autonomous process and has strong institutional underpinnings. We formalise and generalise this "match" (Perez, 1983) argument in accordance with Nelson and Sampat's (2001) framework of physical technology vs social technology and their interactions. Some potential future extensions regarding utilities for this model are then highlighted.
Paolo Capelli - One of the best experts on this subject based on the ideXlab platform.
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Brainstem nucleus MdV mediates skilled forelimb motor tasks
Nature, 2014Co-Authors: Maria Soledad Esposito, Paolo Capelli, Silvia ArberAbstract:Brainstem circuits controlling precision movementTwo papers published in this issue of Nature address a long-standing puzzle in mammalian motor control — the organization and function of circuits between the brain and spinal cord that control motor movements such as reaching. Thomas Jessell and colleagues investigate a class of mouse spinal interneurons known in other species to be involved in fine forelimb movements. They show that in mouse, these neurons have appropriate anatomical innervation to carry both motor commands and an internal copy signal, and ablation of these neurons impairs reaching movements. Furthermore, optogenetic activation of the ascending branch recruits a cerebellar circuit, and also disrupts reaching movements. These findings implicate these neurons as part of an internal copy pathway for rapid updating of motor output during reaching. Silvia Arber and colleagues use a combination of viral tracing and genetics to characterize the diversity of neurons projecting from mouse brainstem to motor neurons that control limb movements. They discover that one region in particular, the ventral medullary reticular formation or MdV, is functionally specialized for forelimb motor control. Neurons here specifically target forelimb neurons and are recruited during motor tasks, and inactivation of these neurons impairs fine movements.AbstractTranslating the behavioural output of the nervous System into movement involves interaction between brain and spinal cord. The brainstem provides an essential bridge between the two structures, but circuit-level organization and function of this Intermediary System remain poorly understood. Here we use intersectional virus tracing and genetic strategies in mice to reveal a selective synaptic connectivity matrix between brainstem substructures and functionally distinct spinal motor neurons that regulate limb movement. The brainstem nucleus medullary reticular formation ventral part (MdV) stands out as specifically targeting subpopulations of forelimb-innervating motor neurons. Its glutamatergic premotor neurons receive synaptic input from key upper motor centres and are recruited during motor tasks. Selective neuronal ablation or silencing experiments reveal that MdV is critically important specifically for skilled motor behaviour, including accelerating rotarod and single-food-pellet reaching tasks. Our results indicate that distinct premotor brainstem nuclei access spinal subcircuits to mediate task-specific aspects of motor programs.The authors use a combination of viral tracing and genetics to characterize the diversity of neurons projecting from mouse brainstem to motor neurons that control limb movements; in particular they discover that the medullary reticular formation ventral part (MdV) is functionally specialized for skilled forelimb motor control.
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Brainstem nucleus MdV mediates skilled forelimb motor tasks
Nature, 2014Co-Authors: Maria Soledad Esposito, Paolo Capelli, Silvia ArberAbstract:Two papers published in this issue of Nature address a long-standing puzzle in mammalian motor control — the organization and function of circuits between the brain and spinal cord that control motor movements such as reaching. Thomas Jessell and colleagues investigate a class of mouse spinal interneurons known in other species to be involved in fine forelimb movements. They show that in mouse, these neurons have appropriate anatomical innervation to carry both motor commands and an internal copy signal, and ablation of these neurons impairs reaching movements. Furthermore, optogenetic activation of the ascending branch recruits a cerebellar circuit, and also disrupts reaching movements. These findings implicate these neurons as part of an internal copy pathway for rapid updating of motor output during reaching. Silvia Arber and colleagues use a combination of viral tracing and genetics to characterize the diversity of neurons projecting from mouse brainstem to motor neurons that control limb movements. They discover that one region in particular, the ventral medullary reticular formation or MdV, is functionally specialized for forelimb motor control. Neurons here specifically target forelimb neurons and are recruited during motor tasks, and inactivation of these neurons impairs fine movements. Translating the behavioural output of the nervous System into movement involves interaction between brain and spinal cord. The brainstem provides an essential bridge between the two structures, but circuit-level organization and function of this Intermediary System remain poorly understood. Here we use intersectional virus tracing and genetic strategies in mice to reveal a selective synaptic connectivity matrix between brainstem substructures and functionally distinct spinal motor neurons that regulate limb movement. The brainstem nucleus medullary reticular formation ventral part (MdV) stands out as specifically targeting subpopulations of forelimb-innervating motor neurons. Its glutamatergic premotor neurons receive synaptic input from key upper motor centres and are recruited during motor tasks. Selective neuronal ablation or silencing experiments reveal that MdV is critically important specifically for skilled motor behaviour, including accelerating rotarod and single-food-pellet reaching tasks. Our results indicate that distinct premotor brainstem nuclei access spinal subcircuits to mediate task-specific aspects of motor programs. The authors use a combination of viral tracing and genetics to characterize the diversity of neurons projecting from mouse brainstem to motor neurons that control limb movements; in particular they discover that the medullary reticular formation ventral part (MdV) is functionally specialized for skilled forelimb motor control.
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Brainstem nucleus MdV mediates skilled forelimb motor tasks
Nature, 2014Co-Authors: Maria Soledad Esposito, Paolo Capelli, Silvia ArberAbstract:Translating the behavioural output of the nervous System into movement involves interaction between brain and spinal cord. The brainstem provides an essential bridge between the two structures, but circuit-level organization and function of this Intermediary System remain poorly understood. Here we use intersectional virus tracing and genetic strategies in mice to reveal a selective synaptic connectivity matrix between brainstem substructures and functionally distinct spinal motor neurons that regulate limb movement. The brainstem nucleus medullary reticular formation ventral part (MdV) stands out as specifically targeting subpopulations of forelimb-innervating motor neurons. Its glutamatergic premotor neurons receive synaptic input from key upper motor centres and are recruited during motor tasks. Selective neuronal ablation or silencing experiments reveal that MdV is critically important specifically for skilled motor behaviour, including accelerating rotarod and single-food-pellet reaching tasks. Our results indicate that distinct premotor brainstem nuclei access spinal subcircuits to mediate task-specific aspects of motor programs.