Whole Brain Mapping of Long-Range Direct Input to Glutamatergic and GABAergic Neurons in Motor Cortex

Long-range neuronal circuits play an important role in motor and sensory information processing. Determining direct synaptic inputs of excited and inhibited neurons is important for understanding the circuit mechanisms involved in regulating movement. Here, we used the monosynaptic rabies tracing technique, combined with fluorescent micro-optical sectional tomography, to characterize the brain-wide input to the motor cortex (MC). The whole brain dataset showed that the main excited and inhibited neurons in the MC received inputs from similar brain regions with a quantitative difference. With 3D reconstruction we found that the distribution of input neurons, that target the primary and secondary MC, had different patterns. In the cortex, the neurons projecting to the primary MC mainly distributed in the lateral and anterior portion, while those to the secondary MC distributed in the medial and posterior portion. The input neurons in the subcortical areas also showed the topographic shift model, as in the thalamus, the neurons distributed as outer and inner shells while the neurons in the claustrum and amygdala were in the ventral and dorsal part, respectively. These results lay the anatomical foundation to understanding the organized pattern of motor circuits and the functional differences between the primary and secondary MC

Experimental study on the milling process of microchannel

In order to improve the milling efficiency of microchannels, the micro milling cutter is proposed to fabricate the microchannel array structures on the aluminum alloy sheet. The processing parameters such as back engagement, feed speed and spindle speed are varied to study their influence on the geometry size of microchannels. The result shows that when using the milling cutter with diameter of 0.4 mm, the width of microchannels increases with the increasing of back engagement and feed speed, especially for the back engagement. When the cutting speed is in the range of 6 000~21 000 r/min, the width size of microchannels barely changes with the increasing of spindle speed. So microchannel array structures can be fabricated through selecting optimized processing parameters

Analysis of Dynamic Characteristics of Clutch-to-Clutch Shifting Control of an Automatic Transmission

The fact that requirements for shift quality in automatic transmissions have been increasing rapidly necessitates the establishment of a suitable shifting control strategy in order to facilitate smoothness of different processes. For this very purpose, this paper introduces a simulation model of an 8-speed automatic transmission for front-drive vehicles with respect to detailed shifting strategies and relative parameters. An impact function can be used to reduce the transmitted torque of the oncoming shift elements before synchronization point in order to damp the impact and thus make the gear shifting process more smooth. This paper makes a systematic introduction of the structure of 8AT, theoretical basis of control strategy, the establishment of the simulation model and the comparison between test results and simulation results. The conclusion shows that with parameters well calibrated, engine torque transferring and speed synchronizing process will be smoother, which helps realizing the ultimate goal of better shift quality with higher efficiency, lower shift loads and improved shifting comfort

Time-sharing control of multi-inverter-module parallel system for frequency multiplication

In order to fulfil the requirements in high-frequency and high-power applications, this paper presents a novel frequency multiplication method, in which N single-phase voltage-type inverter circuits are combined in parallel, being time-sharing controlled in rotation, and the output is through a transformer. The output frequency from the secondary side of the transformer will be increased to N times switching frequency. Using lower-frequency power switching devices for frequency multiplication, this scheme has several advantages. It overcome the limitation of dead-zone time of each inverter, possesses soft switching ability thus reducing the loss in switch tubes, and can be implemented at lower cost. This frequency multiplication method is analysed and simulated on a five-inverter-module system under ten different working conditions, with the associated parameters calculated. A five-module 800 kHz/20 kW prototype has been designed and the test results have shown the validity of the proposed method

Synthesis of hierarchical Sn/SnO nanosheets assembled by carbon-coated hollow nanospheres as anode materials for lithium/sodium ion batteries

This journal is The Royal Society of Chemistry. Tin-based anode materials have aroused interest due to their high capacities. Nevertheless, the volume expansion problem during lithium insertion/extraction processes has severely hindered their practical application. In particular, nano-micro hierarchical structure is attractive with the integrated advantages of nano-effect and high thermal stability of the microstructure. Herein, hierarchical Sn/SnO nanosheets assembled by carbon-coated hollow nanospheres were successfully synthesized by a facile glucose-assisted hydrothermal method, in which the glucose served as both morphology-control agent and carbon source. The hierarchical Sn/SnO nanosheets exhibit excellent electrochemical performances owing to the unique configuration and carbon coating. Specifically, a reversible high capacity of 2072.2 mA h g-1 was observed at 100 mA g-1. Further, 964.1 mA h g-1 after 100 cycles at 100 mA g-1 and 820.4 mA h g-1 at 1000 mA g-1 after 300 cycles could be obtained. Encouragingly, the Sn/SnO also presents certain sodium ion storage properties. This facile synthetic strategy may provide new insight into fabricating high-performance Sn-based anode materials combining the advantages of both structure and carbon coating

Optimal resource allocation for delay constrained users in self-coexistence WRAN

© 2015 IEEE. On Demand Frame Contention (ODFC) is designated as a solution to exclusive self-coexistence in wireless regional area networks. According to ODFC, contention winners are selected in a random manner regardless of the users\u27 delay constraints and frame demands. As a result, ODFC may freeze some users due to that their delay constraints are not satisfied. Moreover, it may lead to a unfair resource distribution in terms of frame demands. To fully consider various delay constraints and frame demands, in this paper we formulate the resource allocation optimization problem as an integer programming problem and present a new approach termed {On Demand Delay-constrained Fair Distribution} (ODDFD). ODDFD utilizes an iterative approach to solve the resource allocation problem considering delay constraints and frame demands. The distinguished feature of ODDFD is that it is able to deal with both delay sensitive networks and delay insensitive networks. Specifically, for a delay sensitive network, ODDFD minimizes jitter variance and average unexpected delay. For a delay insensitive network, the resource is allocated based on their frame demands and achieve a fair distribution in terms of their demands. Extensive simulations are conducted and verify that the jitter variance and average unexpected delay are decreased in a delay sensitive network, and the fairness of frame demands is increased in a delay insensitive network

Structure and electrochemical performance modulation of a LiNi0.8Co0.1Mn0.1O2 cathode material by anion and cation co-doping for lithium ion batteries

Ni-rich layered transition metal oxides show great energy density but suffer poor thermal stability and inferior cycling performance, which limit their practical application. In this work, a minor content of Co and B were co-doped into the crystal of a Ni-rich cathode (LiNi0.8Co0.1Mn0.1O2) using cobalt acetate and boric acid as dopants. The results analyzed by XRD, TEM, XPS and SEM reveal that the modified sample shows a reduced energy barrier for Li+ insertion/extraction and alleviated Li+/Ni2+ cation mixing. With the doping of B and Co, corresponding enhanced cycle stability was achieved with a high capacity retention of 86.1% at 1.0C after 300 cycles in the range of 2.7 and 4.3 V at 25 °C, which obviously outperformed the pristine cathode (52.9%). When cycled after 300 cycles at 5C, the material exhibits significantly enhanced cycle stability with a capacity retention of 81.9%. This strategy for the enhancement of the electrochemical performance may provide some guiding significance for the practical application of high nickel content cathodes