• Journal of the Korean Ceramic Society
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• v.20 no.4
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• pp.315-323
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• 1983

Effect of NiO and $MnO_2$ addtivies on the dielectric piezoelectrics and polarization-reversal properties of $(Pb_{0.936} La_{0.064})$$(Zr_{0.60}Ti_{0.40})O_3$ ceramics have been investigated. The specimens were prepared by the mixed oxide techni-que and atmosphere sintering method. The room temperature X-ray diffraction studies show that perfect perovskite solution with tetragonal structure was obtained from PLZT and its additives. The dielectric constant and dissipation factor decreased with the addition of both NiO and $MnO_2$ The Curie of Curie temperature was not observed but they displayed broadened maxima. The planar coupling factor was improved by addition of NiO and also increased with increasing sintering time carried out at 105$0^{\circ}C$ Addition of $MnO_2$ yielded a markedly high mechanical quality factor. The space-charge field decreased with the addition of NiO but increased with the addition of $MnO_2$ The planar coupling factor and space-charge field showed same dependence on the additivies. The tetragonality Curie temperature and planar coupling factor of $(Pb_{0.936} La_{0.064})$$(Zr_{0.60}Ti_{0.40})O_3$ were higher than those of $(Pb_{0.936} La_{0.064})$$(Zr_{0.568}NU_{0.032}Ti_{0.40})_{0.984}O_3$ but the grain size lattic parameter dielectric constant dissipation factor mechanical quality factor and space-charge field of the former were lower than those of the latter.

• Preventive Nutrition and Food Science
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• v.9 no.3
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• pp.253-258
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• 2004

Stress is a global menace exacerbated by the advancement of industrialization. Failure of stress management is to a breakdown of the psychological and physiological protection mechanisms against stress. The aim of present study was to investigate the anti-stress potential of ginseng against immobilization stress. Male Sprague-Dawley rats (n=24) were divided into three groups; (i) control, (ii) immobilization stress (2hr daily, for 2 weeks), and (iii) immobilization stress (2 hr daily, for 2 weeks) plus oral administration of ginseng (200 mg/kg BW Id). Immobilization stress resulted in a significant inhibition of body weight gain by 45 % and a significant decrease in the tissue weights of thymus and spleen (p < 0.05). The concentrations of blood GOT and GPT were significantly increased in the immobilization-stressed group compared to the control group (p < 0.05). There were no differences in the blood cholesterol levels among groups. Ginseng administration in the immobilization-stressed group tended to reverse the lack of body weight gain and food intake, though not significantly. The ginseng-administered group showed a significant reversal in the stress-induced effect on spleen and thymus weight, increasing the tissue weights by 16% and 20%, respectively, compared to immobilization-stressed group (p<0.05). The plasma corticosterone level was significantly increased in the stressed group by 39 % compared to the control group (p<0.05), but ginseng administration significantly reversed the stress-induced increase in plasma corticosterone by 15 % compared to the immobilization-stressed group. The present study suggests that the anti-stress effect of ginseng is mediated by normalization of stress-induced changes in the circulating hormones and a reversal of tissue weight loss, thereby returning the body to normal homeostasis.

• Science of Emotion and Sensibility
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• v.24 no.3
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• pp.27-40
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• 2021

Because of self-enhancement motives, when involved in social comparison, many people generally value things that are related to themselves, with the representative example being possessions, which is known as the endowment (ownership) effect. However, there are times when someone else's possessions appear to be better than our own, even if they are the same things, which is known as the endowment effect reversal. The purpose of this study was to explore the moderating variable that regulates the endowment effect and the endowment effect reversal by confirming whether the value estimation of others' belongings differed through a regulatory focus as it was surmised that the regulatory focus would moderate the endowment effect of the self versus the others' ownership. Foreign participants were shown the currency of a country they were unfamiliar with and asked to estimate the value in their home country currency. It was found that when people thought the money was their own, people with a promotion focus estimated the value to be higher than people with a prevention focus. However, when they thought it was someone else's money, the regulatory focus moderating effect was not found to be significant, which suggested that the endowment effect may be strengthened or eliminated depending on the individual's regulatory focus. Based on these study results, the implications, limitations, and suggestions for follow-up studies are discussed.

• Biomolecules & Therapeutics
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• v.1 no.1
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• pp.84-92
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• 1993

This study was performed to elucidate the mechanism of antidiuretic action of diltiazem by infusion into the vein and carotid artery, of diuretic action into a renal artery in dog. Renal denervation caused a reversal of the effect of diltiazem from the antidiuretic to the diuretic when infused into vein or carotid artery, and potentiated the diuretic effect when infused into a renal artery. The changes of renal function in diuretic circumstances as described above included the increase in renal plasma flow, osmolar clearance, the amounts of sodium and potassium excreted in urine and the decrease in reabosrption rate of sodium and potassium in renal tubules. Above results suggest that antidiuretic action of diltiazem may be mediated by central nervous system, not by endogenous substance, diuretic action by direct renal action.

• Transactions of Materials Processing
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• v.19 no.5
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• pp.296-304
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• 2010

It is still needed to study the effect of process conditions on the final properties of injection-molded parts for producing precision optical products. Especially, the optical anisotropy, i.e., birefringence, is a significant factor to affect the function of many optical components. In the present study we have focused on the effect of holding and compression processes on the birefringence remaining in the transparent disc by examining the gap-wise distribution of birefringence and extinction angle. As a result, two extra birefringence and extinction peaks near the center in thickness direction showed the effect of holding pressure, which came from the flow in packing stage. However, more uniform birefringence distribution than injection-only cases could be found in injection/compression cases. Depends on the process condition even the flow reversal could be found from the distribution of extinction angle. Finally, graphical representation of optical indicatrix was added for better understanding the final structure of injection-only and injection/compression cases.

• The Journal of Asian Finance, Economics and Business
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• v.8 no.10
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• pp.219-228
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• 2021

The study examines the behavior of stock prices after large price changes. It further examines the effect of firm size on stock returns, and the presence of the disposition effect. The study employs the event study methodology using daily price data from Pakistan Stock Exchange (PSX) for the period January 2001 to July 2012. Furthermore, to examine the factors that explain stock price behavior after large price movements, the study employs a two-way fixed-effect model that allows for the analysis of unobservable company and time fixed effects that explain market reversals or continuation. The findings suggest that winners perform better than losers after experiencing large price shocks thus showing a momentum behavior. In addition, the winners remain the winner, while the losers continue to lose more. This suggests that most of the investors in PSX behave rationally. Further, the study finds no evidence of disposition effect in PSX. The investors underreact to new information and the prices continue to move in the direction of initial change. The pooled regression estimates show that firm size is positively related to post-event abnormal returns while the fixed-effect model reveals the presence of unobservable firm-specific and time-specific effects that account for price continuation.

• Journal of the Korean Society for Heat Treatment
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• v.6 no.1
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• pp.26-36
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• 1993

In this study, the ausformed martensite and marformed martensite obtained from austenite with various deformation degrees in Fe-31% Ni-0.2%C alloy were transformed to revesed austenite at $510^{\circ}C$ by cyclic reverse martensite transformation. The effect of prior deformation, the rapid heating rate of reversion and number of cyclic transformation on the microstructure, mechanical properties of reversed austenite were investigated. The reverse austenite transformation is accomplised by the mechanism of shear type transformation. The structure of reversed austenite formed from ausformed martensite and marformed martensite with high deformation degrees is a fine structure of nearly equiaed grain containg a high density of dislocation tangles and was largely affected by the prior deformation applied before reversal transformation. The strength of reversed austenite is more increased with of cyclic transformation especially it is strength at the first cyclic transformation. The yield stress of revesed austenite of ausformed martensite is lower than that of marformed martensite.

• Earthquakes and Structures
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• v.19 no.4
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• pp.227-241
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• 2020

An experimental study has been carried out to investigate the effect of beam to column connection rigidity on the behavior of infilled steel frames. Five half scale, single-story and single-bay specimens, including four infilled frames, as well as, one bare frame, were tested under in-plane lateral cyclic reversal loading. The connections of beam to column for bare frame as well as two infill specimens were rigid, whereas those of others were pinned. For each frame type, two different infill panels were considered: (1) masonry infill, (2) masonry infill strengthened with shotcrete. The experimental results show that the infilled frames with pinned connections have less stiffness, strength and potential of energy dissipation compared to those with rigid connections. Furthermore, the validity of analytical methods proposed in the literature was examined by comparing the experimental data with analytical ones. It is shown that the analytical methods overestimate the stiffness of infilled frame with pinned connections; however, the strength estimation of both infilled frames with rigid and pinned connections is acceptable.

• Journal of Microbiology and Biotechnology
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• v.5 no.1
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• pp.31-35
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• 1995

An antitumor antibiotic named YS-1649 was isolated from the culture filtrate of a newly isolated fungus identified as Penicillium sp.. The fermentation yield reached about 40 mg per liter of the broth. YS-1649, a $\gamma$-Iactone - structured antibiotic, has the molecular fomular of $C_7H_6O_4$, Its structure was determined to be patulin by spectral analysis. It is active against some bacteria and showed cytotoxic effect on the proliferation of human breast cancer cell line, MCF-7, at concentrations of more than 0.048 $mu g/ml$. This compound also showed strong cytotoxic effect on the proliferation of human cancer cell lines, A549 and ACHN.

• 전기의세계
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• v.21 no.4
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• pp.15-21
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• 1972

For the conventional DC machine, the armature MMF is negligible compared with field MMF except when the machine is under heavy load or transient conditions. During the motor starting or reversal, the transient armature current and corresponding MMF effect the flux density of each pole in the machine magnetic circuit. However, the circuit flux density is restored to normal values by the field winding MMF after the transient armature current dies in an electromagnetic DC motor. Permanent magnet servomotor have no field windings about the circuit poles to restore circuit flux density through the demagnetized part of each pole after the transient armature MMF dies, and portions of the magnetic circuit stay permanently demagnetized. Thus the problem of stabilizing a magnet pole piece under the influence of the transient armature current need attentions. This work present the recoil operation of the servomotor with PM poles in conjunctions with the influence of the armature reaction effect. The development of an analytical and quantatative study is presented for predicting the regime of the recoil operation under this condition.