• Animal cells and systems
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• v.3 no.2
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• pp.167-172
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• 1999

We report for the first time the life history of a 'social' spider, Philoponella prominens, living in a temperate region. Philoponella prominens hibernated as immatures or subadults for 7-8 months in 1995 and 1996 from September-October to April-May in central Korea. When they emerged from their winter hibernation, a majority began their lives as commensals in the webs of other species. As the mating season approached, however, commensal spiders switched to become colonial or solitary. The mating season began in early June and lasted until early August. Newly-hatched spiderlings began to appear in the field in late June. They formed a colony by building their webs connected to the mother's by using pan of the mother's web as supporting substrates. As the season progressed, however, some of the colonial spiderlings became commensal or solitary individuals. Our field observations suggest that Philoponella prominens form colonies or commensal associations to reduce the web-building cost.

• 제어로봇시스템학회:학술대회논문집
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• 1996.10b
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• pp.632-635
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• 1996

Flexible parts can be deformed by the contact forces during assembly on the con to rigid parts and thus their successful assembly requires informations about their deformation as well as a misalignment between mating parts. However, because of the nonlinear and complex relationship between parts deformation and assembly reaction forces, it is difficult to acquire all required informations from only the reaction forces during assembly. In this paper, we propose a sensing system consisting of a camera and multiple mirrors for flexible parts assembly. Simulation results show that the system can be effectively used for detecting parts deformation and a misalignment between mating parts.

• The Plant Pathology Journal
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• v.35 no.4
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• pp.301-312
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• 2019

Sorghum is the fifth most important cereal worldwide, spreading from Africa throughout the world. It is particularly important in the semi-arid tropics due to its drought tolerance, and when cultivated in Southeast Asia commonly occurs as a second crop during the dry season. We recovered Fusarium from sorghum in Thailand and found F. proliferatum, F. thapsinum and F. verticillioides most frequently, and intermittent isolates of F. sacchari and F. beomiforme. The relatively high frequencies of F. proliferatum and F. verticillioides, suggest mycotoxin contamination, particularly fumonisins and moniliformin, should be evaluated. Genetic variation within the three commonly recovered species was characterized with vegetative compatibility, mating type, Amplified Fragment Length Polymorphisms (AFLPs), and female fertility. Effective population number ($N_e$) was highest for F. verticillioides and lowest for F. thapsinum with values based on mating type allele frequencies higher than those based on female fertility. Based on AFLP genetic variation, the F. thapsinum populations were the most closely related, the F. verticillioides populations were the most distantly related, and the F. proliferatum populations were in an intermediate position. The genetic variation observed could result if F. thapsinum is introduced primarily with seed, while F. proliferatum and F. verticillioides could arrive with seed or be carried over from previous crops, e.g., rice or maize, which sorghum is following. Confirmation of species transmission patterns is needed to understand the agricultural systems in which sorghum is grown in Southeast Asia, which are quite different from the systems found in Africa, Australia, India and the Americas.

• 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.

• Asian-Australasian Journal of Animal Sciences
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• v.8 no.5
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• pp.419-425
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• 1995

Twenty growing female Damascus (Shami) goats and twenty growing Chios ewes of two mating ages (10 and 12 months) were used to study the effect of mating age (MA) on reproductive performance (RP). In addition to (RP), The growth, milk production and nutrient requirements were also evaluated. A complete random design in a $2{\times}2$ factorial was used, with (MA) and species as the main factors. (MA) had no effects on (RP), milk production and mortality. No significant difference (p > 0.05) were observed between (MA) or between species, for age at kidding/lambing (K/L). Sheep reached puberty earlier than goats. Average age (months) at conception and at (K/L) was 15.8; 20.8 and l7.0; 22.0 for sheep and goats respectively. Body weight (BW), rather than age was the most important factor determining puberty. Both goats and ewes conceived when they reached about 67% of their mature (BW) for goats and 85% for ewes. Sheep grew faster than goats, but the latter had higher twinning (67.8% versus 25%). Chios sheep were suitable for meat and Shami goats for dairying or dual purpose systems. Nutrient requirements for growth of goats and ewes were similar with an average DM-intake of about 4% (BW); 12-13% CP and 65-69% TDN (DM-basis) of the total ration. It is recommended to breed Chios ewes at a (BW) of at least 50 kg and Shami does at 38 kg, irrespective of their age.

• Korean Journal of Ecology and Environment
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• v.50 no.1
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• pp.116-125
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• 2017

Alpine plants with a scarcity of pollinators in harsh environments have been believed to undergo selfing for reproductive assurance; however, contradictory evidence is also available. Snowmelt regimes in alpine areas function to change life history characteristics of alpine plants such as flowering time and duration; yet the effects of snowmelt regimes have never been tested in alpine plants in Korea. This study was conducted to investigate the dichogamy, mating systems, and flowering characteristics of Megaleranthis saniculifolia populations [early and late snowmelt plots (ESP and LSP, respectively)] in a subalpine area of Sobaeksan Mountain in Korea. M. saniculifolia exhibited incomplete protogyny in that despite early maturation of pistils, maturation times of pistils and stamens within flowers were partly overlapped. Control and hand-outcrossing treatments produced significantly higher number of follicles and seeds per flower than autonomous and hand-selfing treatments. Based on the aggregate fruit set, the auto-fertility index (AI) and self-compatibility index (SI) were 0.33 and 0.50, respectively. Snowmelt occurred 10 days earlier in ESP than in LSP, thereby ESP and LSP showed distinct differences with regard to flower longevity and season, but showing no difference in peak flowering dates. We concluded that M. saniculifolia is an incomplete protogynous and largely outcrossing plant requiring pollinator service. Temporal variation in snowmelt time and subsequent changes in flowering characteristics under climate change may further threaten the population persistence of M. saniculifolia which has already been designated as endangered species in Korea.

• Mycobiology
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• v.49 no.6
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• pp.599-603
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• 2021

CRISPR/Cas9 genome editing systems have been established in a broad range of eukaryotic species. Herein, we report the first method for genetic engineering in pyogo (shiitake) mushrooms (Lentinula edodes) using CRISPR/Cas9. For in vivo expression of guide RNAs (gRNAs) targeting the mating-type gene HD1 (LeA1), we identified an endogenous LeU6 promoter in the L. edodes genome. We constructed a plasmid containing the LeU6 and glyceraldehyde-3-phosphate dehydrogenase (LeGPD) promoters to express the Cas9 protein. Among the eight gRNAs we tested, three successfully disrupted the LeA1 locus. Although the CRISPR-Cas9-induced alleles did not affect mating with compatible monokaryotic strains, disruption of the transcription levels of the downstream genes of LeHD1 and LeHD2 was detected. Based on this result, we present the first report of a simple and powerful genetic manipulation tool using the CRISPR/Cas9 toolbox for the scientifically and industrially important edible mushroom, L. edodes.

• 제어로봇시스템학회:학술대회논문집
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• 1992.10a
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• pp.703-707
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• 1992

In the field of assembly processes, non-rigid parts such as wires, tubes, gaskets and 0-rings cannot be assembled automatically. And although many researches have been made for rigid part mating, there are not substantial studies in flexible parts assembly field. In this paper, assembly stages of flexible parts are classified and some analysis are made. FEM was used to estimate the relationship between deformation and reactive forces. An assembly algorithm adopting reciprocal twisting motion was proposed and the assembly tool design methodology was discussed.

• Mycobiology
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• v.39 no.3
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• pp.143-150
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• 2011

The basidiomycete fungus Cryptococcus neoformans is an important pathogen of immunocompromised people. The ability of the fungus to sense its environment is critical for proliferation and the generation of infectious propagules, as well as for adaptation to the mammalian host during infection. The conserved cAMP/protein kinase A pathway makes an important contribution to sensing, as demonstrated by the phenotypes of mutants with pathway defects. These phenotypes include loss of the ability to mate and to elaborate the key virulence factors capsule and melanin. This review summarizes recent work that reveals new targets of the pathway, new phenotypic consequences of signaling defects, and a more detailed understanding of connections with other aspects of cryptococcal biology including iron regulation, pH sensing, and stress.

• Journal of Institute of Control, Robotics and Systems
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• v.11 no.7
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• pp.615-620
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• 2005

For successful deformable part assembly, information about its deformation as well as possible misalignment between the hole and its respective mating part are essential. Such information can be mainly acquired from visual sensors. In this paper, part deformation and misalignment in deformable cylindrical peg-in-hole tasks are measured by using a visual sensing system. First, a series of experiments to measure the position of an arbitrary point are performed. Next, an algorithm to measure misalignment and part shape as part deformation are presented, and a series of experiments on them are performed. Experimental results show that the proposed algorithms and the system are effective in measuring part deformation and misalignment.