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Same Color (same + color)
Selected AbstractsResponse to novel food and the role of social influences in common marmosets (Callithrix jacchus) and Goeldi's monkeys (Callimico goeldii)AMERICAN JOURNAL OF PRIMATOLOGY, Issue 11 2007Elsa Addessi Abstract Neophobia, defined as showing caution toward novel features of the environment, is widespread in birds and mammals; it can be affected by ecology, early experience, and social context. In this study, we aimed to (i) investigate the response to novel food in adult common marmosets and Goeldi's monkeys and (ii) assess the role of social influences. We used an experimental paradigm employed previously with capuchin monkeys and children, in which a subject (observer) was presented with a novel food under three conditions: (i) Presence: group members did not have food; (ii) Different color: group members received familiar food whose color differed from that of the observer's novel food; (iii) Same color: group members received familiar food of the same color as the observer's novel food. Although most common marmosets tasted and/or ate the novel food, none of the Goeldi's monkeys ate it and only two sampled it. Differences in home range size and early social experience might explain the divergent behavior of the two species. Observers of both species similarly attended to group members and their visual attention increased with the number of group members eating, especially when the observer's and group members' foods were perceptually similar. However, we observed social influences on explorative behavior in Goeldi's monkeys but not on explorative or eating behavior in common marmosets. This result might be explained by the different pattern of response to novel food observed in the two species. Moreover, social influences on Goeldi's monkeys' behavior were nonspecific, i.e. they were not based on an appreciation that the food is safe because eaten by group members. Am. J. Primatol. 69:1210,1222, 2007. © 2007 Wiley-Liss, Inc. [source] Effect of 13 single and eight mixed host plant diets on survival, post-embryonic development and morphology of variegated grasshopper in laboratoryENTOMOLOGICAL RESEARCH, Issue 1 2010Sévilor KEKEUNOU Abstract Zonocerus variegatus (Orthoptera: Pyrgomorphidae) is known as an agricultural pest in West and Central Africa. In this study, the effects of 13 single and eight mixed host plant diets on the survival, post-embryonic development and morphology of Z. variegatus in the laboratory were investigated. In each cage, 20 one-day larvae were provided with these diets and their survival monitored every two days, from August 2000 to September 2002, until all individuals died. Results showed that the number of larval stages varied from six to eight according to the diet. Six larval stages were most frequent. Development to the adult stage (complete development) was only noted with 52% of diets. All the mixed host plant diets induced complete development of Z. variegatus except that of Cajanus cajan + Synedrella nodiflora + Chromolaena odorata. Complete development was observed with four single host plant diets: Lablab purpurea, C. cajan, Manihot esculenta and S. nodiflora. Compared to leguminous species and Asteraceae, M. esculenta (Euphorbiaceae) was the species that resulted in the highest level of survival and development of Z. variegatus. Chromolaena odorata and S. nodiflora (Asteraceae) induced late appearance of the different Z. variegatus nymphal instars and the appearance time was shorter on legumes. The supernumerary stage 7 has the same color as the larva in stages 1,6, but this larva was significantly larger than stage 6 and smaller than the adult stage. These results indicate that legumes for short fallows affected the survival and post-embryonic development of Z. variegatus in the laboratory. [source] On totally multicolored starsJOURNAL OF GRAPH THEORY, Issue 3 2006Juan José Montellano-Ballesteros Abstract Given an edge-coloring of a graph G, a subgraph M of G will be called totally multicolored if no two edges of M receive the same color. Let h(G, K1,q) be the minimum integer such that every edge-coloring of G using exactly h(G, K1,q) colors produces at least one totally multicolored copy of K1,q (the q -star) in G. In this article, an upper bound of h(G, K1,q) is presented, as well as some applications of this upper bound. © 2005 Wiley Periodicals, Inc. [source] Rainbow trees in graphs and generalized connectivityNETWORKS: AN INTERNATIONAL JOURNAL, Issue 4 2010Gary Chartrand Abstract An edge-colored tree T is a rainbow tree if no two edges of T are assigned the same color. Let G be a nontrivial connected graph of order n and let k be an integer with 2 , k , n. A k -rainbow coloring of G is an edge coloring of G having the property that for every set S of k vertices of G, there exists a rainbow tree T in G such that S , V(T). The minimum number of colors needed in a k -rainbow coloring of G is the k -rainbow index of G. For every two integers k and n , 3 with 3 , k , n, the k -rainbow index of a unicyclic graph of order n is determined. For a set S of vertices in a connected graph G of order n, a collection {T1,T2,,,T,} of trees in G is said to be internally disjoint connecting S if these trees are pairwise edge-disjoint and V(Ti) , V(Tj) = S for every pair i,j of distinct integers with 1 , i,j , ,. For an integer k with 2 , k , n, the k -connectivity ,k(G) of G is the greatest positive integer , for which G contains at least , internally disjoint trees connecting S for every set S of k vertices of G. It is shown that ,k(Kn)=n,,k/2, for every pair k,n of integers with 2 , k , n. For a nontrivial connected graph G of order n and for integers k and , with 2 , k , n and 1 , , , ,k(G), the (k,,)-rainbow index rxk,,(G) of G is the minimum number of colors needed in an edge coloring of G such that G contains at least , internally disjoint rainbow trees connecting S for every set S of k vertices of G. The numbers rxk,,(Kn) are determined for all possible values k and , when n , 6. It is also shown that for , , {1, 2}, rx3,,(Kn) = 3 for all n , 6. © 2009 Wiley Periodicals, Inc. NETWORKS, 2010 [source] Probabilistic strategies for the partition and plurality problemsRANDOM STRUCTURES AND ALGORITHMS, Issue 1-2 2007k Dvo We consider a game played by two players, Paul and Carol. Carol fixes a coloring of n balls with three colors. At each step, Paul chooses a pair of balls and asks Carol whether the balls have the same color. Carol truthfully answers yes or no. In the Plurality problem, Paul wants to find a ball with the most common color. In the Partition problem, Paul wants to partition the balls according to their colors. Paul's goal is to ask Carol the fewest number of questions to reach his goal. We find optimal probabilistic strategies for the Partition problem and the Plurality problem in the considered setting. © 2006 Wiley Periodicals, Inc. Random Struct. Alg., 2007 [source] Response to novel food and the role of social influences in common marmosets (Callithrix jacchus) and Goeldi's monkeys (Callimico goeldii)AMERICAN JOURNAL OF PRIMATOLOGY, Issue 11 2007Elsa Addessi Abstract Neophobia, defined as showing caution toward novel features of the environment, is widespread in birds and mammals; it can be affected by ecology, early experience, and social context. In this study, we aimed to (i) investigate the response to novel food in adult common marmosets and Goeldi's monkeys and (ii) assess the role of social influences. We used an experimental paradigm employed previously with capuchin monkeys and children, in which a subject (observer) was presented with a novel food under three conditions: (i) Presence: group members did not have food; (ii) Different color: group members received familiar food whose color differed from that of the observer's novel food; (iii) Same color: group members received familiar food of the same color as the observer's novel food. Although most common marmosets tasted and/or ate the novel food, none of the Goeldi's monkeys ate it and only two sampled it. Differences in home range size and early social experience might explain the divergent behavior of the two species. Observers of both species similarly attended to group members and their visual attention increased with the number of group members eating, especially when the observer's and group members' foods were perceptually similar. However, we observed social influences on explorative behavior in Goeldi's monkeys but not on explorative or eating behavior in common marmosets. This result might be explained by the different pattern of response to novel food observed in the two species. Moreover, social influences on Goeldi's monkeys' behavior were nonspecific, i.e. they were not based on an appreciation that the food is safe because eaten by group members. Am. J. Primatol. 69:1210,1222, 2007. © 2007 Wiley-Liss, Inc. [source] Scale and skew-invariant road sign recognitionINTERNATIONAL JOURNAL OF IMAGING SYSTEMS AND TECHNOLOGY, Issue 1 2007Yi-Sheng Liu Abstract A fast and robust method to detect and recognize scaled and skewed road signs is proposed in this paper. In the detection stage, the input color image is first quantized in HSV color model. Border tracing those regions with the same colors as road signs is adopted to find the regions of interest (ROI). The ROIs are then automatically adjusted to fit road sign shape models so as to facilitate detection verification even for scaled and skewed road signs in complicated scenes. Moreover, the ROI adjustment and verification are both performed only on border pixels; thus, the proposed road sign detector is fast. In the recognition stage, the detected road sign is normalized first. Histogram matching based on polar mesh is then adopted to measure the similarity between the scene and model road signs to accomplish recognition. Since histogram matching is fast and has high tolerance to distortion and deformation while contextual information can still be incorporated into it in a natural and elegant way, our method has high recognition accuracy and fast execution speed. Experiment results show that the detection rate and recognition accuracy of our method can achieve 94.2% and 91.7%, respectively. On an average, it takes only 4,50 and 10 ms for detection and recognition, respectively. Thus, the proposed method is effective, yet efficient. © 2007 Wiley Periodicals, Inc. Int J Imaging Syst Technol, 17, 28,39, 2007 [source] | |||||||||||||