• Title/Summary/Keyword: avoidance response

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High-light avoidance response of chloroplasts and reorganization of actin filaments are induced only in the exposed area to blue light in the epidermal cell of Vallisneria gigantea

  • Sakurai, Nami;Domoto, Kikuko;Takagi, Shingo
    • Journal of Photoscience
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    • v.9 no.2
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    • pp.326-328
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    • 2002
  • In many plant cells, the positions of chloroplasts change in response to changes in light conditions. In the epidermal cells of the aquatic angiosperm Vallisneria gigantea, the avoidance response of chloroplasts is induced specifically by irradiation with blue light of high intensity. Possible roles of actin cytoskeleton in the blue-light-induced avoidance response of chloroplasts were investigated by partial irradiation and phalloidin staining. We showed that the blue-light-dependent redistribution of chloroplasts was induced only in the limited area, where exposed to blue light, even in individual cells. In addition. in the exposed area, the configuration of actin filaments strikingly changed compared with that before the irradiation. Short and thick bundles of actin filaments surrounding the chloroplasts changed to much longer and thinner bundles with a more stretched array. In contrast, in the unexposed area, neither the distribution of chloroplasts nor the configuration of actin filaments exhibited any changes. Cytochalasin D and latrunculin B inhibited the avoidance response of chloroplasts concomitantly with the fragmentation of actin filaments. These results indicate that the reorganization of actin filaments plays a crucial role in the induction of avoidance response of chloroplasts.

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Shade Avoidance and the Regulation of Leaf Inclination in Rice

  • Shin, Juhee;Park, Phun Bum
    • Rapid Communication in Photoscience
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    • v.3 no.3
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    • pp.53-55
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    • 2014
  • The shade avoidance syndrome is a morphological and physiological response when plants are exposed to shade. Recent work in Arabidopsis had begun to define the molecular components of the shade avoidance syndrome in dicotyledonous model plant. However, little is known about the shade avoidance response networks in agriculturally important monocotyledon crops such as rice. Here, we found that the degree of bending at the lamina joint is inversely proportional to the R:FR ratio. To elucidate which phytochrome is involved in this response, we did lamina joint inclination assay with the rice phytochrome-deficient mutants (osphyA, osphyB, and osphyC) and the wild type plants. Whereas the osphyA and osphyC knockout mutants bent at the lamina joint in the far-red rich condition as the wild type plants, the osphyB knockout mutants no longer bent at the lamina joint in the far-red rich condition. These results suggest that PHYB acts as a sole photoreceptor in the lamina joint inclination response in rice.

Modeling Jamming Avoidance Response of Pulse-type Weakly Electric Fish (전기물고기의 방해 회피 반응 모델링과 응용)

  • Soh, JaeHyun;Kim, DaeEun
    • Journal of Institute of Control, Robotics and Systems
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    • v.21 no.10
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    • pp.924-929
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    • 2015
  • In this paper, we suggest a phase difference algorithm inspired by weakly electric fish. Weakly electric fish is a fish which generates electric field though its electric organ in the tail. The weakly electric fish search for prey and detect an object by using electrolocation. The weakly electric fish have Jamming Avoidance Response (JAR) to avoid jamming signal. One of pulse-type weakly electric fish Gymnotus carapo also have JAR to reduce the probability of coincidence of pulses. We analyze this response signal and design the phase difference algorithm. We expect that simple algorithm inspired by weakly electric fish can be used in many engineering fields.

Predictors of anxiety and depression in Korean adults during COVID-19 pandemic (COVID-19 팬데믹 시대 성인의 불안과 우울의 예측 요인)

  • Sohn, Jung Nam
    • The Journal of Korean Academic Society of Nursing Education
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    • v.28 no.3
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    • pp.328-339
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    • 2022
  • Purpose: This study was conducted to identify the mental health status of Korean adults during the COVID-19 pandemic and to verify the predictors and mediating effects of avoidance coping on the relationship between the intolerance of uncertainty and anxiety and the intolerance of uncertainty and depression. Methods: An online survey was completed by 191 Korean adults from 19 to 64 years old. Using the IBM SPSS Win 19.0 program, the data were analyzed through the frequency, mean, t-test or analysis of variance, Pearson's correlation coefficient, linear regression analysis and Sobel test. Results: Of the survey respondents 21.5%, and 33.5% respectively were classified into anxiety and depression risk groups. The predictors of anxiety were intolerance of uncertainty (β=.52), avoidance coping (β=.21), and response efficacy (β=-.15). Those variables explained 47.7% of the respondents' anxiety. The predictors of depression were intolerance of uncertainty (β=.40), avoidance coping (β=.20), and response-efficacy (β=-.12). These variables explained 34.9% of the participants' depression. Among the predictors of anxiety and depression, avoidance coping was the significant mediating variable. Conclusion: The predictors of anxiety and depression during the COVID-19 pandemic were revealed to be intolerance of uncertainty, avoidance coping, and response-efficacy. These results indicate the necessity of providing the cognitive interventions and reducing the use of avoidance coping strategies on a personal level. Community-level efforts, including early detection and health communication strategies, should prioritize risk groups for example young adults. The study suggests it will be necessary to provide sufficient information, psychological support and economic policy alternatives related to the COVID-19 pandemic on the national level.

Competition Responses of Populus alba Clone ‘Bolleana’ to red:far-red light

  • Bae, Han-hong;Kang, Ho-duck;Richard B. Hall
    • Plant Resources
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    • v.7 no.1
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    • pp.77-86
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    • 2004
  • The reduced ratio of red:far-red (R:FR) light acts as a measure of the proximity of competitors and plants can detect the potentially competing neighbor plants by perceiving reflected R:FR signals and initiate the response of “shade avoidance” before actual shading occurs. The phytochrome system is responsible for monitoring the changes in the R:FR and initiating the shade avoidance response. The response to low R:FR ratio was studied in a white aspen Populus alba clone ‘Bolleana’ using two filter systems: a clear plastic filter system that allows a R:FR ratio less than 1.0 to pass from adjacent border plant reflection; and a special commercial plastic that blocks FR light and creates a R:FR ratio above 3.0. The reduced R:FR signals enhanced the stem elongation in response to competition at the expense of relative stem diameter growth. Trees grown inside clear chambers were 27 % taller than trees grown inside the FR-blocking filter chambers. Stem taper of clear chamber trees was 16% less than the FR-blocking filter trees. Low R:FR also induced 22% more stem dry weight and 13% greater petiole length per leaf compared to the FR-blocking filter trees. There were no statistically significant differences in leaf area, leaf number increment, and total dry weight between the two light filter treatments.

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Towards a Redundant Response Avoidance for Intelligent Chatbot

  • Gwon, Hyuck-Moo;Seo, Yeong-Seok
    • Journal of Information Processing Systems
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    • v.17 no.2
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    • pp.318-333
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    • 2021
  • Smartphones are one of the most widely used mobile devices allowing users to communicate with each other. With the development of mobile apps, many companies now provide various services for their customers by studying interactive systems in the form of mobile messengers for business marketing and commercial promotion. Such interactive systems are called "chatbots." In this paper, we propose a method of avoiding the redundant responses of chatbots, according to the utterances entered by the user. In addition, the redundant patterns of chatbot responses are classified into three categories for the first time. In order to verify the proposed method, a chatbot is implemented using Telegram, an open source messenger. By comparing the proposed method with an existent method for each pattern, it is confirmed that the proposed method significantly improves the redundancy avoidance rate. Furthermore, response performance and variation analysis of the proposed method are investigated in our experiment.

An Economic Analysis of the Enforcement of illegal Fishing in Traditional Fisheries Management (전통적 어업관리의 불법어업 감시·감독에 대한 경제학적 분석)

  • LEE, Sang-Go
    • Journal of Fisheries and Marine Sciences Education
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    • v.14 no.1
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    • pp.57-73
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    • 2002
  • Illegal fishing is often cited as a principal cause of the failure of fisheries management, expecially fishing efforts regulations in traditional fisheries management. Usually, illegal fishing problems are perceived to be equivalent to inadequate enforcement, and policy prescription then follow to strengthen enforcement programs. The purpose of this paper is to analyze the illegal fishing behavior relatively recent emphasis on fishing efforts regulations in traditional fisheries management. The analysis focuses on measuring, explaining and developing the effectiveness way of enforcement strategies responding to imperfectly managed fishing efforts regulations through illegal fishing behavior and avoid enforcement fishing efforts measures. A model of fishermen fishing behavior and profit-maximizing decision making is analyzed to determine optimal fishing at individual fisherman level in response to fishing efforts regulation. The results of economic analysis of the enforcement of illegal fishing in traditional fisheries management results are as follows: First, illegal fishing will occur only if enforcement effort is not so high as to remove the incentive to do so, and if the effectiveness of avoidance is not too great, nor its cost too low. Second, avoidance effort will occur at a level jointly proportional to the extent of illegal activity and of enforcement; for given levels of the latter, the desired avoidance effort increase with its effectiveness and decrease with its cost Third, to improve the effectiveness of enforcement, understanding avoidance behavior appears to be crucial to any efforts. Forth, enforcement and fishermen behavior interact depends strongly on characteristics of avoidance, specifically its cost and effectiveness. When avoidance is neither too cheap nor too effective, the interaction is regular. Fifth, in this case, at low levels of enforcement, fishers respond to increases in enforcement by increasing avoidance, but at higher enforcement levels, it becomes uneconomical to continue to do so, and avoidance decreases with enforcement. Sixth, illegal fishing activity decreases steadily with enforcement, so the fishery manager is able, in theory, to reduce illegal fishing toward zero by increasing enforcement. If, however, avoidance is very inexpensive and/or very efficient/ then the optimal level of avoidance will increase indefinitely with increasing enforcement. Finally, less fishery enforcement is required if fishermen have less incentive to overfish, and fishermen have less incentive to avoid fishery enforcement measures.

Impairments of Learning and Memory Following Intracerebroventricular Administration of AF64A in Rats

  • Lim, Dong-Koo;Oh, Youm-Hee;Kim, Han-Soo
    • Archives of Pharmacal Research
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    • v.24 no.3
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    • pp.234-239
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    • 2001
  • Three types of learning and memory tests (Morris water maze, active and passive avoidance) were performed in rats following intracerebroventricular infusion of ethylcholine aziridium (AF64A). In Morris water maze, AF64A-treated rats showed the delayed latencies to find the platform iron 6th day after the infusion. In pretrained rats, AF64A caused the significant delay of latency at 7th days but not 8th day. In the active avoidance for the pretrained rats, the escape latency was significantly delayed in AF64A-treatment. The percentages of avoidance in AF64A-treated rats were less increased than those in the control. Especially, the percentage of no response in the AF64A-treated rats was markedly increased in the first half trials. In the passive avoidance, AF64A-treated rats shortened the latency 1.5 h after the electronic shock, but not 24 h. AF64A also caused the pretrained rats to shorten the latency 7th day after the infusion, but not 8th day. These results indicate that AF64A might impair the learning and memory. However, these results indicate that the disturbed memory by AF64A might rapidly recover after the first retrain. Furthermore, these results suggest that AF64A may be a useful agent for the animal model of learning for Spatial cognition .

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A Study on Fuzzy Controller for Autonomous Mobile Robot (자율 이동 로보트의 퍼지 제어기에 관한 연구)

  • 주영훈;황희수;고재원;김성권;황금찬;우광방
    • The Transactions of the Korean Institute of Electrical Engineers
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    • v.41 no.9
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    • pp.1071-1084
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    • 1992
  • In this paper, the method for navigation and obstacle avoidance of the autonomous mobile robot is proposed. The proposed algorithms are based on the fuzzy inference system which is able to deal with imprecise and uncertain information. The self-tuning algorithm, which adopts the simplex method, modifies the parameters of membership functions of the input-output linguistic variables by changing the support of these fuzzy sets according to the integral of absolute error(IAE) of the system response. The wall-follwing navigation and obstacle avoidance of the mobile robot are based on range data measured from the internal sensors(encoder) and the outer sensors(sonar sensor). In addition, the algorithm for the obstacle detection proposed in this paper is based on the expert's experience. Finally, the effectiveness of navigation and obstacle avoidance algorithm is demonstrated through simulation and experiment.

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The Economic Analysis of the Determination of Optimal Management Measures and Level of Control in Fisheries Management (불완전 어업관리의 합리적 관리수단 및 규제수준의 결정에 관한 경제학적 분석)

  • 이상고;김도훈
    • The Journal of Fisheries Business Administration
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    • v.33 no.2
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    • pp.31-48
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    • 2002
  • This paper is aimed to analyze how to evaluate the choice of optimal management measures and level of control in fisheries management under the costly and imperfect management system by comparing with costless and perfect management system that is commonly assumed in the analysis of fisheries regulations. Fishermen would set the level of fishing efforts at the point where the marginal fishing profit for fishing effort is equal to the marginal level of fine under costly and imperfect management system. Therefore, under the case where the marginal fishing profit is higher than the marginal level of fine, the level of fishing efforts would be made at the point which is higher than the level of fishing efforts made under costless and perfect management system and is not a point where the economic profit is maximized in regulated fisheries. From this conclusion, the fishermens avoidance activities against regulations as well as the level of control in fisheries management substantially have an influence on the choice of fisheries management instruments. According to the analysis of optimal fisheries management policy, the economic profits in regulated fisheries are determined by the level of fisheries enforcement costs and total fishing profits, in which as enforcement costs increase the economic profits decrease. In addition, the economic profits vary in response to the level of control in avoidance activities. That is, as avoidance costs decrease, the economic profits increase. The determination of optimal level of control in fisheries management should be made at the point where the marginal regulation costs are equal to the marginal profits from regulated fisheries, in which marginal regulation costs are different according to the type of management measures. And the level of profits changes in response to different levels of avoidance activities. The management measure that can maximize the difference between the marginal regulation costs and marginal profits from regulated fisheries should be chosen as an optimal fisheries management instrument.

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