• Title/Summary/Keyword: sexual selection

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Battle of the sexes over paternity

  • Kim, Young-Joon;Lee, Kang-Min;Isaac, R. Elwyn
    • BMB Reports
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    • v.48 no.5
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    • pp.241-242
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    • 2015
  • Reproductive behaviors have evolved through severe inter-sexual competition. We have recently described a behavior in post-mated female Drosophila melanogaster that controls ejaculate retention and sperm storage, and is a possible mechanism by which females who have mated with several partners can choose which sperm that is stored and used for fertilization. This behavior can also regulate exposure of the female to harmful effects of male SFP that are present in the ejaculate. Our study identified the neural pathway functioning in the female brain that regulates this behavior. [BMB Reports 2015; 48(5): 241-242]

Genetic Algorithm Based Economic Dispatch with Valve Point Effect (Valve Point 효과가 고려된 경제급전에서의 유전알고리즘 응용)

  • Park, Jong-Nam;Park, Kyung-Won;Kim, Ji-Hong;Kim, Jin-O
    • The Transactions of the Korean Institute of Electrical Engineers A
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    • v.48 no.3
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    • pp.203-211
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    • 1999
  • This paper presents a new approach on genetic on genetic algorithm to economic dispatch problem for valve point discontinuities. Proposed approach in this paper on genetic algorithms improves the performance to solve economic dispatch problem for valve point discontivuities through improved death penalty method, generation-apart elitism, atavism and sexual selection with sexual distinction. Numerical results on a test system consisting of 13 thermal units show that the proposed approach is faster, more robust and powerful than conventional genetic algorithms.

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Multi-Objective Optimization Technique Using Genetic Algorithm and Its Application to Design of Linear Induction Motor (유전알고리즘을 이용한 선형유도전동기의 다중목적 최적설계)

  • Ryu, K.B.;Choi, Y.J.;Kim, C.E.;Kim, S.W.;Park, Y.C.;Kim, J.H.;Im, D.H.
    • Proceedings of the KIEE Conference
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    • 1994.07a
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    • pp.165-167
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    • 1994
  • This paper presents a new method for multiobjective optimization using Genetic Algorithm-Sexual Reproduction Model(SR model). In SR model, each individual consists of chromosome pairs. Sex cells(gametes) are produced through artificial meiosis in which crossover and mutation occur, The proposed method has two selection operators, one, individual selection which selects the individual to fertilize, and the other, gamete selection which makes zygote for offspring production, The two selection schemes are repectively conducted according to different fitness(or objective) function and consequently give a solution which is unbiased to any objectives. We apply the proposed method to optimization of the design parameters of Linear Induction Motor(LIM) and show its effectiveness.

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Further Evidence for the Role of Cantharidin in the Mating Behaviour of Blister Beetles (Coleoptera: Meloidae)

  • Nikbakhtzadeh, Mahmood Reza;Hemp, Claudia;Ebrahimi, Babak
    • Animal cells and systems
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    • v.11 no.2
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    • pp.141-146
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    • 2007
  • Cantharidin is produced by blister beetles (Coleoptera: Meloidae) and smaller oedemerid beetles (Coleopetra: Oedemeridae) and is found in hemolymph and various tissues. The function of cantharidin in the courtship behaviour of meloids had never been fully established. Our studies show a correlation between density of cuticular pores and cantharidin titre of the scape and pedicel segments of male specimens of the East African species of Epicauta nyassensis (Haag-Rutenberg, 1880) (Coleoptera: Meloidae). Light microscopy of semi-thin cross sections of the male scape and pedicel indicates that there are many canal shaped structures that stretch from the antennal hemolymph to the antennomere surface. These structures may be tubules, which transport cantharidin circulating in the hemolymph to the surface, where the compound can be released via cuticular pore openings. Analyses of the head capsule and antennal segments of E. nyassensis females which had been copulated with males revealed low titre of cantharidin in the first two antennal segments. The density of the scape and pedicel pores of females was to some extent higher than the density of these pores on flagellum; however it was considerably lower than that of the males. Interestingly, no tubular cell or other transport structures were found in the cross sectioning of the female antennomeres or on the integument surface. During mating, male antennomeres, as well as cantharidin containing pores which are located on the $1^{st}\;and\;2^{nd}$ antennomeres, come into direct contact with the female antennae and may release cantharidin to their surface. Female E. nyassensis may be able to discriminate the opposite sex with abundant reserves of cantharidin prior to mating. This is another evidence that cantharidin function in close range sexual selection.

Asymmetries in Chickens from Lines Selected and Relaxed for High or Low Antibody Titers to Sheep Red Blood Cells

  • Tu, Yunjie;Siegel, P.B.
    • Asian-Australasian Journal of Animal Sciences
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    • v.28 no.3
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    • pp.323-327
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    • 2015
  • Wattle length, width, and area were measured to classify bilateral asymmetries in four lines of chickens. The lines were the S26 generation of White Leghorns selected for high (HAS) or low (LAS) response to sheep red blood cells and sublines in which selection had been relaxed for three generations (high antibody relaxed [HAR] and low antibody relaxed [LAR]). Antibody titers (AB) were greater for HAS than for HAR with both greater than for LAS and LAR which while different for males did not differ for females. The low antibody lines were heavier and reached sexual maturity at younger age than the high antibody lines. In general, wattle length, width, and area were greater in the low than high antibody lines. In 24 comparisons for bilaterality 18 exhibited fluctuating asymmetry and 6 exhibited directional asymmetry with 5 of the 6 being for wattle length. There was not a clear pattern for changes in degree of asymmetry when selection was relaxed for 3 generations. For females, the relative asymmetry (RA) of wattle area was larger ($p{\leq}0.05$) for HAR than for LAR and not different from the selected lines and relaxed lines. There were no differences among lines for RA of wattle length and width of females and wattle length, width, and area of males.

Effects of Selection by Serum IGF-I Concentration in Korean Native Ogol Chicken

  • Kim, D. H.;Kim, M. H.;W. J. Kang;D. S. Seo;Y. Ko
    • Proceedings of the KSAR Conference
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    • 2003.06a
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    • pp.20-20
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    • 2003
  • Phenotypic characteristics and genetic markers in livestock have been utilized for improvement of the economic traits including egg productivity. Korean Native Ogol Chicken (KNOC) has low egg productivity compared to White Leghorn. Therefore, in this study, serum IGF-I concentration and number of egg production were used as selection markers to improve egg productivity. KNOCs were divided into three groups showing high IGF-I concentration (IGF-I high), high egg production (EP high), and IGF-I/EP high groups. Blood was collected every 10 weeks, and serum concentrations of IGF-I, estradiol (E2), and progesterone (P4) were measured by radioimmunoassay. In comparison of three groups in each generation, the highest increment of egg production was detected in the IGF-I/EP high group from 20 weeks till 40 weeks, and the IGF-I high group also showed the significant increment of egg production after 50 weeks. Interestingly, there were the increase of egg production and decrease of periods in sexual maturity in the second and third generation selected by serum IGF-I concentration, while egg weight and body weight decreased during experimental period. In conclusion, the present study suggest the possibility of IGF-I as a selection marker to improve the egg productivity of KNOC.

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Development of PCR-based markers for discriminating Solanum berthaultii using its complete chloroplast genome sequence

  • Kim, Soojung;Cho, Kwang-Soo;Park, Tae-Ho
    • Journal of Plant Biotechnology
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    • v.45 no.3
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    • pp.207-216
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    • 2018
  • Solanum berthaultii is one of the wild diploid Solanum species, which is an excellent resource in potato breeding owing to its resistance to several important pathogens. On the other hand, sexual hybridization between S. berthaultii and S. tuberosum (potato) is limited because of their sexual incompatibility. Therefore, cell fusion can be used to introgress various novel traits from this wild species into the cultivated potatoes. After cell fusion, it is crucial to identify fusion products with the aid of molecular markers. In this study, the chloroplast genome sequence of S. berthaultii obtained by next-generation sequencing technology was described and compared with those of five other Solanum species to develop S. berthaultii specific markers. A total sequence length of the chloroplast genome is 155,533 bp. The structural organization of the chloroplast genome is similar to those of the five other Solanum species. Phylogenic analysis with 25 other Solanaceae species revealed that S. berthaultii is most closely located with S. tuberosum. Additional comparison of the chloroplast genome sequence with those of the five Solanum species revealed 25 SNPs specific to S. berthaultii. Based on these SNPs, six PCR-based markers for differentiating S. berthaultii from other Solanum species were developed. These markers will facilitate the selection of fusion products and accelerate potato breeding using S. berthaultii.

Psychology of Young Adulthood (청년기심리 (靑年期心理))

  • Cho, Doo-Young
    • Korean Journal of Psychosomatic Medicine
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    • v.5 no.2
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    • pp.223-236
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    • 1997
  • One faces four major developmental tasks to achieve in young adulthood, ages between 20 and 40 : intimacy, vocation, marriage and child-rearing. Intimacy is the capacity to commit oneself to concrete affiliations and partnerships and to develop the ethical strength to abide by such commitments, even though they call for significant sacrifices and compromises. Through vocation and marriage young adults become united to networks of persons, find tasks that demand involvement, and gain roles into which they fit and are fitted and which help define their identities. An occupation represents much more than a set of skills and functions : it means a way of life. The extent of vocational choice increases with educational level, and the unconscious factors are frequency the decisive element. The vocational choice stare with fantasy choices in childhood, passes through tentative choices in adolescence, realistic choices in college days, and crystallized choices in post-college days, and finally ends up to the choice of specification. Along with the hazards and the need for realignment of personality functioning, the marriage brings with it new opportunities for self-fulfillment and completion. Motives other than a romantic love gain more importance in the decision to marry and in the choice of a partner. The impulsions to marry are sexual gratification, the desire to propagate, narcissistic gratification, and a need of interdependence. Many factors such as oedipal wishes, sexuality and sexual attractions, socio-economic classes, and geography involve in selection of marriage partner. There are also various motivations to marry a romantic love, the desire for a home of one's own, sexual attractions, the wish for security and a shelter, and the wish for children. The hostile marriage, the marriage on the rebound, the marriage rooted in rescue fantasies, and sado-masochistic marriage are the examples of pathological marriages. A successful marriage will usually both Lead to and require a marked reorganization of the personality structure of each partner that will influence the lurker personality development of each. Many marital problems are largely dependent upon the personality characteristics of one partner which might well create difficulties no manor who was the spouse.

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Monitoring Differences in Vaginal Hemodynamic and Temperature Response for Sexual Arousal by Different Anesthetic Agents Using an O ptical Probe

  • Jeong, Hyeryun;Seong, Myeongsu;Park, Kwangsung;Kim, Jae Gwan
    • Current Optics and Photonics
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    • v.4 no.1
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    • pp.57-62
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    • 2020
  • The selection of anesthetic agent is important in preclinical studies, since each agent affects the systemic hemodynamics in different ways. For that reason, we hypothesized that different anesthetic agents will result in different vaginal hemodynamic response and temperature during sexual arousal, in an animal model. To validate the hypothesis, animal experiments were performed using female rats with two anesthetic agents widely used in preclinical studies: ketamine and isoflurane. Our previously developed near-infrared-spectroscopy-based probe was used to measure the changes of oxyhemoglobin (OHb), deoxyhemoglobin (RHb), and total hemoglobin (THb) concentrations along with temperature from the animal vaginal wall. As a control, saline was administered to both isoflurane- and ketamine-anesthetized animals, and did not show any significant changes in OHb, RHb, THb, or temperature. However, an administration of apomorphine (APO, 80 ㎍/kg) induced increases of OHb (63 ± 28 μM/DPF), RHb (35 ± 20 μM/DPF), and THb (98 ± 49 μM/DPF) in ketamine-anesthetized animals, while decreases of OHb (52 ± 76 μM/DPF) and THb (38 ± 30 μM/DPF) and an increase of RHb (28 ± 51 μM/DPF) were found in isoflurane-anesthetized animals. The vaginal temperature decreased from the baseline in both ketamine-(0.42℃) and isoflurane-(1.22℃)anesthetized animals. These results confirmed our hypothesis, and suggest that a preclinical study monitoring hemodynamic responses under anesthesia should employ an appropriate anesthetic agent for the study.

Assessing the association of single nucleotide polymorphisms in thyroglobulin gene with age of puberty in bulls

  • Fernandez, Maria Elena;Goszczynski, Daniel Estanislao;Prando, Alberto Jose;Peral-Garcia, Pilar;Baldo, Andres;Giovambattista, Guillermo;Liron, Juan Pedro
    • Journal of Animal Science and Technology
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    • v.56 no.5
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    • pp.17.1-17.4
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    • 2014
  • Puberty is a stage of sexual development determined by the interaction of many loci and environmental factors. Identification of genes contributing to genetic variation in this character can assist with selection for early pubertal bulls, improving genetic progress in livestock breeding. Thyroid hormones play an important role in sexual development and spermatogenic function. The objective of this study was to evaluate the association between single nucleotide polymorphisms (SNPs) located in thyroglobulin(TG) gene with age of puberty in Angus bulls. Four SNPs were genotyped in 273 animals using SEQUENOM technology and the association between markers and puberty age was analyzed. Results showed a significant association (P < 0.05) between these markers and puberty age estimated at a sperm concentration of 50 million and a progressive motility of 10%. This is the first report of an association of TG polymorphisms with age of puberty in bulls, and results suggest the importance of thyroidal regulation in bovine sexual development and arrival to puberty.