Studies on Aggressive Behavior in Mice

It is important to elucidate aggressive behavior for effective domestic animal management. Aggressiveness in mice, our model domestic animal, is partly caused by genetic factors. It has not, however, been studied in detail. The present study was designed to produce high and low aggression, inbreeding coefficient changes, and reproductive performance by selection. In addition, we investigated the effects of different population sizes on aggression, and also intracerebral dynamic neurotransmitters. Genetically different, high(H) and low(L) aggression mice were produces by selection. Our estimated values of heritability and realized heritability of aggression indicated that aggresiveness is influenced mainly by the environment. Inbreeding coefficients in H and L mice showed an increase of about 2% per generation, and 68.2 and 67.1% in the 34th generation of selection. Reproductive performance decreased slightly during selection, induced by the increase in inbreading coefficients. Isolated H mice induced the highest aggressiveness, without inducing aggressive behavior in isolated L mice. This result indicates that there is a genetic difference in the aggression control system between H and L mice. The serotonin turnover rate is reduced further in H mice than in L mice before the aggression test, suggesting that the serotonergic system is related to aggressive behavior. There were significant differences in dopamine levels between H and L mice. Results obtained from autoreceptor agonists indicate that H mice exhibit a high dopamine biosynthesis and release rate, while H and L mice differ in their aggression auto-control system through autoreceptors in the presynapse. H and L mice exhibit different aggressive behavior changes due to concentrations of dopamine D1 receptors.家畜の管理にあたって、攻撃行動の解析は重要な課題である。家畜のモデル動物であるマウスでは、攻撃性を発現させる要因の1つに遺伝的要因が挙げられるが、十分な解析がなされていない。そこで、本研究は、マウスの攻撃性について選抜育種を行い、攻撃性の遺伝率を推定するとともに、選抜世代に伴う近交係数と生産能力の推移について検討し、つぎに攻撃性に及ぼす飼育密度の影響について検討した。さらに攻撃性に関与するとみられる脳内神経伝達物質の動態について検討した。攻撃性の選抜結果、遺伝的に攻撃性の異なる2つの系統（高・低攻撃性系統：H系・L系）の作出に成功した。また、攻撃性の遺伝率、実現遺伝率の値はともに低い値となり、攻撃性は環境の影響を強く受けることが示唆された。H系・L系での選抜に伴う近交係数は1世代当り約2％増加し、選抜34世代では、各々68.2、67.1%の値を示した。両系統ともに選抜を伴い、繁殖能力のわずかな低下が認められたが、これは近交係数の上昇に起因したものと考察した。攻撃行動に及ぼす飼育密度の影響についてみると、H系では個別飼育が最も高い攻撃行動を示し、これに対してL系では個別飼育でもほとんど攻撃性は認められなかった。このことから、H系とL系では闘争抑制機構に遺伝的差異が生じてきたことが示唆された。脳内神経伝達物質について検討した結果、攻撃試験を行わない場合にはH系ではL系に比べてセロトニンの代謝回転は有意に低い値を示した。このことは、H系ではセロトニン代謝が抑制され、一方L系では亢進しており、攻撃行動にはセロトニンの重要な関与が示唆された。また、H系とL系では、ドーパミン量にも明らかな差異がみられた。さらに、ドーパミンD2受容体のシナプス前にある自己受容体に対する特異的なアゴニスト（BHT920)を用いた実験の結果から、H系はL系に比較してドーパミン生合成と放出率が高く、H系とL系ではシナプス前にある自己受容体を介した自己抑制性の機構に差異があることが示唆された。攻撃性の異なるH系とL系ではドーパミンD1受容体量にも差がみられ、両系統でのドーパミン放出量と関係していることが示唆された

On Auslander's n-gorenstein rings

AbstractAccording to Auslander, a Noetherian ring R is called n-Gorenstein for n ≥ 1 if in a minimal injective resolution 0 → RR → E0 → E1 → … → En →, …, the flat dimension of each Ei is at most i for i = 0, 1, …, n − 1. We prove that for an n-Gorenstein ring R of self-injective dimension n, the last term En in a minimal injective resolution of RR has essential socle.We also prove that the 1-Gorenstein property is inherited by a maximal quotient ring, and as a related result, we characterize a Noetherian ring of dominant dimension at least 2

MOTION CHARACTERISTICS AFFECT EVALUATION BY JUDGES IN HIP-HOP DANCE: KINEMATIC ANALYSIS OF STEP MOVEMENT

The purpose of this study was to extract motion characteristics closely related to high evaluation by judges, through a comparison of “side-step” movement between eight expert and eight non-expert dancers. Their step motions were captured and the head trajectory relative to the centre of mass, face inclination, and time lags among neck, trunk, hip and knee angles were calculated. As a result, a quarter cycle of phase delay between the neck motion and other body parts were observed for the expert dancers. This delay resulted in a large displacement of the head relative to the centre of mass and a large range of motion of the face inclination. The face inclination was highly correlated with the judging score (r = 0.869). Thus, it is assumed these motion characteristics are the most important element of the side-step movement that induces a better impression of judges

MOTION CHARACTERISTICS IN HIP HOP DANCE UNDERLYING SUBJECTIVE EVALUATION OF THE PERFORMANCE

The purpose of this study was to extract the motion characteristics that are closely related to the subjective evaluation of hip hop dance performance. The subjects were 11 expert, six non-expert and nine novice hip hop dancers. Each dancer performed the “wave“ motion as the experimental task. Movements of upper extremities during the task were captured by a motion capture system and several kinematic parameters including the propagation velocity of the wave (PV) were calculated. We found that the coefficient of variance of the PV was highly correlated with the subjective evaluation by the judges (r=0.770,

Temperature and Voltage Estimation Using Ring-Oscillator-Based Monitor for Field Test

Field test is performed in diverse environments, in which temperature varies across a wide range. As temperature affects a circuit delay greatly, accurate temperature monitors are required. They should be placed at various locations on a chip including hot spots. This paper proposes a flexible ring-oscillator-based monitor that accurately measures voltage as well as temperature at the same time. The measurement accuracy was confirmed by circuit simulation for 180 nm, 90 nm and 45 nm technologies. An experiment using test chips with 180 nm technology shows its feasibility.2014 IEEE 23rd Asian Test Symposium (ATS), 16-19 Nov. 2014, Hangzhou, Chin