Allelopathic effort of penguin excrements and guanos on the growth of Antarctic soil algae

An experiment was carried out to ascertain the effect of substances in the soil of Adelie penguin rookery on the growth of algae isolated from the Antarctic soil. In the paper disc test, both of acetone and water extracts of guano soil gave an inhibitive effect on the algal growth. It was recognized that acrylic and oxalic acids were the algal growth inhibitors. The function of the oxalic acid as a new growth inhibitor of algae was examined by comparing it with that of acrylic acid

カエル聴覚器の神経活動

金沢大学医学部研究課題/領域番号:X00080----848073, 研究期間(年度):1973 – 1974出典：「カエル聴覚器の神経活動」研究成果報告書　課題番号：X00080----848073（KAKEN：科学研究費助成事業データベース（国立情報学研究所）） （https://kaken.nii.ac.jp/ja/grant/KAKENHI-PROJECT-X00080----848073/）を加工して作

Design and performance of a F/#-conversion microlens for Prime Focus Spectrograph at Subaru Telescope

The PFS is a multi-object spectrograph fed by 2394 fibers at the prime focus of Subaru telescope. Since the F/# at the prime focus is too fast for the spectrograph, we designed a small concave-plano negative lens to be attached to the tip of each fiber that converts the telescope beam (F/2.2) to F/2.8. We optimized the lens to maximize the number of rays that can be confined inside F/2.8 while maintaining a 1.28 magnification. The microlenses are manufactured by glass molding, and an ultra-broadband AR coating (<1.5% for lambda=0.38-1.26 um) will be applied to the front surface.Comment: 7 pages, 8 figures, SPIE201

Identification of inhibitory premotor interneurons activated at a late phase in a motor cycle during Drosophila larval locomotion

This work was supported by a MEXT/JSPS KAKENHI Grant Numbers, 22115002 (to A.N.) and 221S0003 (to A.N. and Y.I.), and 15H04255 (to A.N.). The work was also supported by Janelia Research Campus (Howard Hughes Medical Institute).Rhythmic motor patterns underlying many types of locomotion are thought to be produced by central pattern generators (CPGs). Our knowledge of how CPG networks generate motor patterns in complex nervous systems remains incomplete, despite decades of work in a variety of model organisms. Substrate borne locomotion in Drosophila larvae is driven by waves of muscular contraction that propagate through multiple body segments. We use the motor circuitry underlying crawling in larval Drosophila as a model to try to understand how segmentally coordinated rhythmic motor patterns are generated. Whereas muscles, motoneurons and sensory neurons have been well investigated in this system, far less is known about the identities and function of interneurons. Our recent study identified a class of glutamatergic premotor interneurons, PMSIs (period-positive median segmental interneurons), that regulate the speed of locomotion. Here, we report on the identification of a distinct class of glutamatergic premotor interneurons called Glutamatergic Ventro-Lateral Interneurons (GVLIs). We used calcium imaging to search for interneurons that show rhythmic activity and identified GVLIs as interneurons showing wave-like activity during peristalsis. Paired GVLIs were present in each abdominal segment A1-A7 and locally extended an axon towards a dorsal neuropile region, where they formed GRASP-positive putative synaptic contacts with motoneurons. The interneurons expressed vesicular glutamate transporter (vGluT) and thus likely secrete glutamate, a neurotransmitter known to inhibit motoneurons. These anatomical results suggest that GVLIs are premotor interneurons that locally inhibit motoneurons in the same segment. Consistent with this, optogenetic activation of GVLIs with the red-shifted channelrhodopsin, CsChrimson ceased ongoing peristalsis in crawling larvae. Simultaneous calcium imaging of the activity of GVLIs and motoneurons showed that GVLIs' wave-like activity lagged behind that of motoneurons by several segments. Thus, GVLIs are activated when the front of a forward motor wave reaches the second or third anterior segment. We propose that GVLIs are part of the feedback inhibition system that terminates motor activity once the front of the motor wave proceeds to anterior segments.Publisher PDFPeer reviewe