Development of a Stator-Magnetless Linear Synchronous Motor for Sensorless Control

Sensorless control techniques that do not use a linear scale are desired for applications that require a long-stroke linear synchronous motor (LSM). This paper discusses the development of a stator-magnetless LSM (i.e., no magnet is mounted on the stator of the LSM) for sensorless control that includes a high-speed position estimation algorithm based on the magnetic saturation phenomenon. This paper presents a new structure of a flux-switching LSM that achieves a high saliency ratio using a cutout that results in magnetic saturation in the armature core. The effect of the sub-tooth on reducing the cogging thrust is also discussed. Furthermore, the analytical and experimental characteristics of inductance, thrust, cogging thrust, and sensorless drive control are discussed based on a prototype

AUTS2 Governs Cerebellar Development, Purkinje Cell Maturation, Motor Function and Social Communication

Autism susceptibility candidate 2 (AUTS2), a risk gene for autism spectrum disorders (ASDs), is implicated in telencephalon development. Because AUTS2 is also expressed in the cerebellum where defects have been linked to ASDs, we investigated AUTS2 functions in the cerebellum. AUTS2 is specifically localized in Purkinje cells (PCs) and Golgi cells during postnatal development. Auts2 conditional knockout (cKO) mice exhibited smaller and deformed cerebella containing immature-shaped PCs with reduced expression of Cacna1a. Auts2 cKO and knock-down experiments implicated AUTS2 participation in elimination and translocation of climbing fiber synapses and restriction of parallel fiber synapse numbers. Auts2 cKO mice exhibited behavioral impairments in motor learning and vocal communications. Because Cacna1a is known to regulate synapse development in PCs, it suggests that AUTS2 is required for PC maturation to elicit normal development of PC synapses and thus the impairment of AUTS2 may cause cerebellar dysfunction related to psychiatric illnesses such as ASDs

Type-1 metabotropic glutamate receptor signaling in cerebellar Purkinje cells in health and disease [version 1; referees: 3 approved]

The cerebellum is a brain structure involved in coordination, control, and learning of movements, as well as certain aspects of cognitive function. Purkinje cells are the sole output neurons from the cerebellar cortex and therefore play crucial roles in the overall function of the cerebellum. The type-1 metabotropic glutamate receptor (mGluR1) is a key “hub” molecule that is critically involved in the regulation of synaptic wiring, excitability, synaptic response, and synaptic plasticity of Purkinje cells. In this review, we aim to highlight how mGluR1 controls these events in Purkinje cells. We also describe emerging evidence that altered mGluR1 signaling in Purkinje cells underlies cerebellar dysfunctions in several clinically relevant mouse models of human ataxias

Combining electrophysiology and optogenetics for functional screening of pyramidal neurons in the mouse prefrontal cortex

Summary: Here, we present a comprehensive protocol to analyze the roles of disease-related genes in synaptic transmission. We have developed a pipeline of electrophysiological techniques and combined these with optogenetics in the medial prefrontal cortex of mice. This methodology provides a cost-effective, faster, and easier screening approach to elucidate functional aspects of single genes in several regions in the mouse brain such as a specific layer of the mPFC.For complete details on the use and execution of this protocol, please refer to Nagahama et al. (2020) and Sacai et al. (2020)

Effect of fat emulsion administration on blood coagulation in terminal lung cancer patients

Objectives: Patients with cancer, especially those with lung cancer, are at high risk of developing thrombosis. Intralipos® infusion 20% is contraindicated for thrombosis, and there is no consensus on whether it can be safely used in cases of advanced cancer. We conducted a retrospective observational study to elucidate the impact of fat emulsion administration on blood coagulation in patients with terminal lung cancer. Methods: The subjects were patients with terminal lung cancer in the Department of Surgery and Palliative Medicine, Fujita Health University Nanakuri Memorial Hospital between January 2016 and December 2019. We compared changes in their blood coagulation profile before hospitalization and one month later. Results: There were a total of 213 patients with lung cancer—139 who were administered fat emulsion and 74 who were not—with no significant differences in baseline characteristics. In the fat emulsion administration group (n=27), the prothrombin time-international normalized ratio (PT-INR) and activated partial thromboplastin time (APTT), respectively, were 1.17±0.26 (mean±standard deviation) and 30.5±5.0 s at hospitalization and 1.16±0.12 and 31.2±4.2 s one month later with no significant differences. In the non-administration group (n=6), the PT-INR and APTT, respectively, were 1.44±0.43 and 30.6±5.2 s before hospitalization and 1.28±0.18 and 33.0±7.5 s one month later with no significant differences. Conclusions: We did not identify any changes in PT-INR and APTT after fat emulsion administration in patients with terminal lung cancer. There were also no new cases of thrombosis, suggesting that fat emulsions were administered safely in patients with terminal lung cancer

mGluR5 Is Substitutable for mGluR1 in Cerebellar Purkinje Cells for Motor Coordination, Developmental Synapse Elimination, and Motor Learning

Group I metabotropic glutamate receptors (mGluRs) include mGluR1 and mGluR5, which are coupled to the Gq family of heterotrimeric G-proteins and readily activated by their selective agonist 3,5-dihydroxyphenilglycine (DHPG). mGluR1 and mGluR5 exhibit nearly complementary distributions spatially or temporally in the central nervous system (CNS). In adult cerebellar Purkinje cells (PCs), mGluR1 is a dominant group I mGluR and mGluR5 is undetectable. mGluR1 expression increases substantially during the first three weeks of postnatal development and remains high throughout adulthood. On the other hand, mGluR5 expression is observed during the first two postnatal weeks and then decreases. However, functional differences between mGluR1 and mGluR5 in the CNS remains to be elucidated. To address this issue, we generated “mGluR5-rescue” mice in which mGluR5 is specifically expressed in PCs in global mGluR1-knockout (KO) mice. mGluR5-rescue mice exhibited apparently normal motor coordination, developmental elimination of redundant climbing fiber (CF)-PC synapses, and delay eyeblink conditioning, which were severely impaired in mGluR1-KO mice. We concluded that mGluR5 is functionally comparable with mGluR1 in cerebellar PCs

Autism spectrum disorder-like behavior caused by reduced excitatory synaptic transmission in pyramidal neurons of mouse prefrontal cortex

CNTNAP2 or AHI1 are autism-associated genes. Here the authors show using knockdown of the genes that this results in reduced excitatory synaptic transmission in layer 2/3 pyramidal neurons in the prefrontal cortex and is associated with impaired social interaction in mice