1,720,995 research outputs found
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Function of food-entrainable clock neurons in the dorsomedial hypothalamic nucleus
Full text link毎日固定した一定時間帯でのみ餌が得られる環境下では、動物は給餌前数時間にわたり食物探索行動を示し、給餌時間内に十分量摂食するように順応する。この食餌同期性概日行動リズムは、哺乳類の概日リズム制御中枢・視交叉上核(SCN)とは別の生物時計(食餌同期性クロック)によって制御されるが、その詳しいメカニズムは分かっていなかった。本研究で、食餌同期性クロックが機能するためには、脳内の視交叉上核以外の場所における時計遺伝子Bmal1の働きが必要であることが明らかになった。When food availability is temporally restricted to a fixed time of the day(restricted feeding), animals adapt to this condition within a few days by feeding during the period of food availability and increasing food-seeking activity in the preceding hours. These changes in biological rhythms have been postulated to be brought about by a food-entrainable oscillator(FEO) that is independent of the mammalian master clock in the suprachiasmatic nucleus(SCN), although little is known of the physical and molecular substrates of the FEO. In this study, we demonstrated that an SCN-independent FEO in the nervous system requires a clock gene, Bmal1, and plays a critical role in adaptation of circadian locomotor activity and food intake to restricted feeding.研究課題/領域番号:20390056, 研究期間(年度):2008–2011出典：研究課題「食餌同期性概日リズムを刻む視床下部背内側核ニューロンの機能解析」課題番号20390056
（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/report/KAKENHI-PROJECT-20390056/20390056seika/）を加工して作成金沢大学医薬保健研究域医学系research repor
Neural mechanisms underlying the circadian pacemakers
Full text link研究成果の概要（和文）：哺乳類の中枢概日ペースメーカー・視交叉上核（SCN）は多種・多数のニューロンから成る神経ネットワークである。しかし、SCNが強固で安定した概日振動を発振するために必要な神経ネットワークの動作原理は明らかでない。本研究では、ニューロンタイプ特異的遺伝子操作、概日行動リズム解析、SCNにおけるin vivo, ex vivoでの遺伝子発現解析などを行い、SCNのAVP産生ニューロンが安定した概日リズムの発振、周期の決定に極めて重要な役割を果たすことを明らかにした。The suprachiasmatic nucleus (SCN), the primary circadian pacemaker in mammals, is a network structure composed of multiple types of neurons. However, the neural mechanisms underlying the generation of robust and stable circadian oscillation by the SCN network remains unknown. We generated mice with neuron type-specific genetic manipulations and performed analyses of their behavior, gene expression in vivo and ex vivo, and so on. We found that AVP producing neurons in the SCN play a critical role in the generation of stable circadian behavioral rhythms and the determination of the circadian period.研究課題/領域番号:24390052, 研究期間(年度):2012-04-01 - 2016-03-31出典：研究課題「概日ペースメーカー神経ネットワークの動作原理」課題番号24390052
（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/report/KAKENHI-PROJECT-24390052/24390052seika/）を加工して作成金沢大学医薬保健研究域医学系research repor
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Full text linkWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Integrated understanding of the light entrainment mechanism encompassing the entire central circadian clock
Full text linkThe central circadian clock in the suprachiasmatic nucleus (SCN) of the hypothalamus is synchronized to the day-night cycle of the external world transmitted from the retina (light entrainment). Light information is first transmitted to the core cells, and then information is sent from the core to the shell, resulting in a phase shift of the entire SCN. The signal transduction mechanisms of core cells have been well studied. However, for light entrainment to be established, the shell, which has a large number of cells and large circadian oscillations, must also undergo a phase shift and become fixed, but this process is not known. We have obtained mice with dramatically altered light-entrainment ability by specific genetic manipulation of the SCN shell, and have analyzed it in detail.視床下部視交叉上核（SCN）の中枢体内時計は、網膜から伝わる外界の昼夜サイクルに同調する（光同調）。SCNは背内側部（shell）と腹外側部（core）の二領域に大別される。光情報はまずcore細胞に伝えられ、coreからshellに情報が送られ、SCN全体の位相がシフトする。入力部・core細胞の情報伝達については研究が進んでいる。しかし光同調の成立には、細胞数も多く概日振動も大きいshellでも位相がシフトして固定される必要があるが、この過程は不明である。我々はSCN shellの特異的遺伝子操作により光同調能が劇的に変化したマウスを得たので、その詳細な解析を行った。研究課題/領域番号:20K21498, 研究期間(年度):2020-07-30 – 2022-03-31出典：研究課題「中枢体内時計全体を包括した光同調メカニズムの統合的理解」課題番号20K21498
（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/report/KAKENHI-PROJECT-20K21498/20K21498seika/）を加工して作成金沢大学医薬保健研究域医学系research repor
Development of a novel gene therapy on narcolepsy using AAV vectors and artificial GPCRs
Full text linkナルコレプシーは強い眠気と情動性脱力発作（カタプレキシー）を主症状とする睡眠障害であり、その病態にオレキシン産生ニューロン（オレキシンニューロン）の変性・脱落が関わる。しかし、オレキシンニューロンがナルコレプシーを抑制するメカニズムは不明であった。 本研究ではマウスにおいて、青斑核・ノルアドレナリンニューロンと背側逢線核・セロトニンニューロンがオレキシンニューロンの下流で働き、前者は強い眠気、後者はカタプレキシーを抑制することを明らかにした。また、これらのニューロンを人為的に活性化してナルコレプシーを抑制する方法を開発した。The loss of orexin neurons in humans is associated with narcolepsy, a sleep disorder characterized by excessive daytime sleepiness and cataplexy. However, the precise neural mechanisms downstream of orexin neurons remain unknown.
We found that the locus coeruleus noradrenergic and dorsal raphe serotonergic neurons play differential roles in the regulation of sleep/wakefulness by orexin neurons: the former stabilizes wakefulness episodes (reduce sleepiness) and the latter suppresses cataplexy in mice. In addition, we developed a system to suppress narcolepsy in mice by artificially activating these neurons using recombinant AAV vectors and an artificial GPCR called DREADD.研究課題/領域番号:23659134, 研究期間(年度):2011–2013出典：研究課題「AAVベクターと人工GPCRを用いたナルコレプシーの遺伝子治療法の開発」課題番号23659134
（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/report/KAKENHI-PROJECT-23659134/23659134seika/)を加工して作成金沢大学医薬保健研究域医学系research repor
Dispelling the Myths Behind First-author Citation Counts
Full text linkWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
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