• 한국버섯학회지
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• 제9권1호
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• pp.3-16
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• 2011

In the bipolar basidiomycete Pholiota nameko, a pair of homeodomain protein genes located at the A mating-type locus regulates mating compatibility. In the present study, we used a DNA-mediated transformation system in P. nameko to investigate the homeodomain proteins that control the clamp formation. When a single homeodomain protein gene (A3-hox1 or A3-hox2) from the A3 monokaryon strain was introduced into the A4 monokaryon strain, the transformants produced many pseudo-clamps but very few clamps. When two homeodomain protein genes (A3-hox1 and A3-hox2) were transformed either separately or together into the A4 monokaryon, the ratio of clamps to the clamp-like cells in the transformants was significantly increased to approximately 50%. We, therefore, concluded that the gene dosage of homeodomain protein genes is important for clamp formation. When the sip promoter was connected to the coding region of A3-hox1 and A3-hox2 and the fused fragments were introduced into NGW19-6 (A4), the transformants achieved more than 85% clamp formation and exhibited two nuclei per cell, similar to the dikaryon (NGW12-163 ${\times}$ NGW19-6). The results of real-time RT-PCR confirmed that sip promoter activity is greater than that of the native promoter of homeodomain protein genes in P. nameko. So, we concluded that nearly 100% clamp formation requires high expression levels of homeodomain protein genes and that altered expression of the A mating-type genes alone is sufficient to drive true clamp formation.

• 한국패류학회지
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• 제31권2호
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• pp.113-121
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• 2015

Gametogenesis, mating behaviour and spawning of Octopus ocellatus were investigated by histological study. This species is dioecious, and showed a protandry phenomenon. Ooogenesis (in females) and spermatogenesis (in males) can be classified into 3 stages, respectively. O. ocellatus copulates in one of two ways: a male may leap upon a female, mounting her mantle, or a male may sit near the female and extend the hectocotylized third right arm toward her. Spawning occurred between April and June in females, and between March and May in males of O. ocellatus. The spawning period was once a year and the peak took place between May and June. A number of flatened follicle cells, which were attached to an oocyte, were involved in vitellogenesis in the cytoplasm of the vitellogenic oocyte (maturing oocyte), and formation of chorion membrane (secondary egg membrane) of the ovarian eggs. Fecundity per female closely related to GSI was 294-660 eggs (average, 429 eggs). The diameters of the ovarian eggs surrounded by chorion membrane were approximately in the range of 10.10-2.50 mm. Each ovarian egg laid by a female was connected to an egg string. Each egg string was 1-5.5 cm (average 3.6 cm). The total number of eggs laid by a female of this species ranged 218-314, the egg sizes were independent to the size of female adult. this species has a life mode showing some special reproductive characteristics of an annual semelparity as shown in Octopodidae species because we have never seen a female spawning a second time.

• 한국양봉학회지
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• 제33권4호
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• pp.251-260
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• 2018

Instrumental insemination of honey bee is an attractive alternative to natural mating in breeding program as it allows mating crosses between desirable queen and specific drone. However, nursery condition that the queen is kept before and after insemination is major factor affected to the performance of instrumentally inseminated queen. In this study, we evaluated the influences of three different nursery-conditions of push-in cages, mini nuclei and normal colonies on number of spermatozoa stored in the spermatheca, body weight, onset of ovipositon and performance of instrumentally inseminated Apis cerana queen. Our results demonstrated that instrumentally inseminated queens kept in mini nuclei and in normal hives showed no significant difference in queen's weight (159.8 and 166.2mg, respectively), number of spermatozoa in spermatheca ($2.02{\times}10^6$ and $2.76{\times}10^6$, respectively), proportion of queen supersedure (33.3 and 66.7% queen survival at 11 months after oviposition, respectively) and brood production, compared to naturally mated queens. In contrast, instrumentally inseminated queens kept in push-in cages showed significant difference of those above data in comparison to queens mated naturally. Our results suggested that instrumentally inseminated queens could be kept in mini nuclei containing about 1.000 attendant bees to have desirable performance of queen whereas the push-in method should be practiced for the purpose of using queen in the length of time less than 7 months.

• The Korean Journal of Ecology
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• 제17권3호
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• pp.299-310
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• 1994

종 내의 클론 상호작용은 개체군 구조에 중요한 영향을 미친다. 본 연구는 클론간의 경쟁에 의해 개체군 내에서 진화적 변화가 일어날 수 있는 가를 조사하고, 균일한 실험실 배양 조건에서 어떻게 다양한 클론이 진화하는지를 밝히고자 하였다. 자원소비율과 교배형이 다른 Polysphondylium pallidum의 클론들이 선택되었다. 실험은 T0에서 T4까지 4번의 시간 간격을 두고 시행되었다. 접종 후 자실체를 수확할 때까지의 한 번의 실험기간은 10~14일 정도 소요되었다. T0의 50개의 클론으로부터 일련의 실험기간 T1, T2, T3, T4에서 50 클론이 두 세트씩 만들어졌다. 개체군들의 자원소비율 변동은 T0와 두세트의 T4 클론들간에 비교되었다. 각 클론은 실험 시작 후 48~56세대가 지난 후에도 균일하고 제한된 Cerophyl 배지 환경에서 다양한 자원 소비율 즉, 다양한 생장율을 보였다. 생장율이 다른 다양한 클론은 서식처가 이질적인 토양 미세 환경 뿐만 아니라 한 장소의 균질한 배양 접시 속에서도 공존 할 수 있었다. 높은 클론 다양성은 한 개체군내의 클론에서 다른 클론을 만날 기회를 제공해 주었고 개체군내의 클론 경쟁이 활발히 일어났다. T0에서 T4까지의 총 실험 기간동안 교배형 I이었던 37개의 클론중에서 한 개체군의 31개가 교배형 II로 바뀌어 클론간에 일어난 경쟁배타율은 0.838이었다. 각 교배형의 출현 빈도는 연속적인 다음 세대마다 0.93~1.29% 만큼 바뀌었다. 2.6X108밀도의 박테리아를 먹이로 제공해 준 실험실 환경에서 한 세대가 지날 때 마다 한 클론에서 다른 클론으로 변화하는 진화적 변화확률이 1.26~1.75%라는 것을 의미한다.

• Asian-Australasian Journal of Animal Sciences
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• 제14권5호
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• pp.697-700
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• 2001

A prolonged farrowing interval is common on small farms in Nepal and may be attributable to the absence of boar contact at the time of weaning. To examine whether synthetic boar pheromone spray might be of value to aid the stimulation and detection of estrus, 30 village farms, each with a single sow, were recruited into a field study. All sows entered the study on final weaning from their first lactation at 56 days post partum. For 13 treatment sows, a boar pheromone spray (SOA, Intervet, Boxmeer, The Netherlands) was applied each day after weaning whilst 17 other sows did not receive any stimulus (negative control). When estrous was detected by the farmer, sows were taken to the nearest boar for service. There was a significantly shorter weaning to re-mating interval for treatment sows (42.9 V 82.2 day, p<0.05), with a significantly higher proportion of treatment sows rebred by day 60 after weaning (p=0.024, Fishers Test). It is concluded that use of boar pheromones can improve reproductive efficiency of sows kept under Nepalese village conditions.

• 한국안전학회지
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• 제21권3호
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• pp.1-7
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• 2006

Nowadays, out of other transmission parts, the sleeve is getting more and more important part for exact and smooth shifting from gear ratio change whenever drivers are needed. To exact and smooth shifting when drivers are needed, all the parts connected with gear shifting should be machined exactly and having dimensions designers are intended. Especially, in case of the sleeve that the most important functional part to shift from gear ratio change that drivers are intended, it needs high precision grade and quality in both sides runout and outer dia runout as well as inner spline small dia & large dia. Because it's assembled with the synchro hub spline and shifted directly with the mating cone. So, it should be applied the hear treatment(hereinafter referred to H.T.M.T) to prevent the friction and percussion loss from shifting with mating cone. At this time, the deformation problems are raised from almost H.T.M.T. process and it makes the inferior part.

• Tribology and Lubricants
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• 제36권5호
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• pp.290-296
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• 2020

When two layers of carbon nanotube (CNT) arrays are loaded to mate, the free ends of individual CNTs come into contact at the interface of the two layers. This leads to a higher contact resistance due to a smaller contact region. However, when the free CNT ends of one array penetrate into the mating array, the contact region increases, effectively lowering the contact resistance. To explore the penetration of mating CNTs, we perform molecular dynamic simulations of a simple unit cell model, incorporating four CNTs in the lower array layer coupled with a single moving CNT on the upper layer. The interaction with neighboring CNTs is modelled by long-range carbon bond order potential (LCBOP I). The model structure is optimized by energy minimization through the conjugate gradient method. A NVT ensemble is used for maintain a room temperature during simulation. The time integration is performed through the velocity-Verlet algorithm. A significant vibrational motion of CNTs is captured when penetration is not available, resulting in a specific vibration mode with a high frequency. Due to this vibrational behavior, the random behaviors of CNT motion for predicting the penetration are confirmed under the specific gap distances between CNTs. Thus, the probability of penetration is examined according to the gap distance between CNTs in the lower array and the aspect ratio of CNTs. The penetration is significantly affected by the vibration mode due to the van der Waals forces between CNTs.

• Interdisciplinary Bio Central
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• 제3권4호
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• pp.13.1-13.8
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• 2011

Previous research has established the existence of individual differences with regards to individuals' optimum time of well-functioning; specifically in terms of being either morning or evening oriented. An association has also emerged between being more evening, as opposed to morning, oriented and having a greater number of sexual partners. The aim of the present study was to investigate whether "eveningness" in males is an evolved sexually dimorphic trait consistent across different cultures. A sample of 179 male Sri Lankan men residing in two different cultural and economic settings, Italy and Sri Lanka, were administered the Morningness-Eveningness Questionnaire (MEQ) followed by assessing their sexual behavior history. The results robustly portrayed a highly significant main effect of MEQ types highlighting the twofold sexual success enjoyed by the evening individuals in both regional locations. Morning oriented individuals, showed a stronger preference for going out and partying than evening-types, suggesting that the higher mating success of evening types is not due to their different lifestyles allowing more opportunities to encounter females. However, evening types exhibited a preference for flirtatious behaviors in the later part of the day. Shoulder-to-hip and handgrip strength, as measures of testosterone levels, were not significantly associated with eveningness. The results are discussed in terms of sexual selection and its interplay with human cultural variation.

• The Korean Journal of Physiology
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• 제8권1호
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• pp.15-22
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• 1974

The influence, upon male rat's mating behavior, of Korean Panax Ginseng administered for 3 and 5 days was investigated by direct behavioral observation and also by counting the number of copulation plugs the animals deposited. Four쇼-four male albino rats were used. Part of the animals received ginseng for 3 days (ginseng-3 day group, N= 12) or for 5 days(ginseng-5 day group, H=10), while the remaining animals received saline for 3 days (saline-3 day group, N=12) or for 5 days (saline-S day group, N=10). Each animal belonging to the 2 ginseng groups received subcutaneously 0.5 ml/100 g body weight of ginseng alcohol extract solution (4 mg of the ethyl alcohol extract in 1 ml of physiological saline), and each rat belonging to the 2 saline groups received the same amount of saline per day. During the dark period of the light-dark cycle on the next day following the last drug administration, a female rat in the artificial estrus was introduced to each male and the mating behavior was observed for 45 minutes. The observation session was divided into two parts and, in the early part which terminated with the first ejaculation and succeeding intromission, following behavioral measures were taken: mounting latency, intromission latency, inter-intromission period, ejaculatory latency(time from the first intromission until the first ejaculation), occurrence of mounting with intromission, occurrence of mounting without intromission, and postejaculatory interval. Behavioral measures taken in the later part of the session after the first ejaculation were: occurrence of mounting with intromission, occurrence of mounting without intromission, and occurrence of ejaculation. Immediately after the behavioral observation session the experiment turned to measure, for 10 days, the number of copulation plug which each pair of rats deposited. Following results were obtained: 1. After several mountings mounting with intromission, males of the 2 ginseng groups finished the first ejaculation significantly earlier than the corresponding 2 saline groups did. 2. The postejaculatory latency was significantly reduced in the ginseng-5 day group compare with the value of the saline-5 day group and also compared with the value of the ginseng-3 day group. 3. The 2 ginseng groups ejaculated significantly more often in 45 minutes' observation session than the corresponding 2 saline groups did. 4. The number of copulation plug deposited in 10 days by the animals of the 2 ginseng groups. significantly exceeded the number deposited by the corresponding 2 saline group animals. The animals of the ginseng-5 day group deposited copulation plugs significantly more than the animals of the ginseng-3 day group did. It is inferred from the above results that the ginseng facilitates mating behavior of male rats, and that the degree of facilitation may be influenced by the duration of drug administration.

• 생태와환경
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• 제50권1호
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• pp.116-125
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• 2017

극한 기후에서 수분매개자가 부족한 고산식물은 번식보장을 위해 자가수정을 겪는 것으로 믿어졌다; 그러나 반대되는 증거도 있다. 고산지역에서 융설체제는 고산식물의 개화시기와 개화기간 같은 생활사 특성을 변화시키는 기능을 한다; 그러나 국내의 고산식물에 대한 융설체제 효과는 검정된 바 없다. 본 연구에서는 소백산 정상부의 아고산식물인 모데미풀의 자웅이숙성, 교배체제, 두 개체군[이른 융설 구역과 늦은 융설 구역(각기 ESP와 LSP)]의 개화특성을 조사하였다. 모데미풀은 암술과 수술의 성숙시기가 부분적으로 겹치는 불완전 자예선숙성을 나타냈다. 교배실험의 결과 대조구와 인공타가수분 처리구가 자율 및 인공자가수분 처리구보다 꽃당 골돌 및 종자를 유의하게 더 많이 생산하였다. 취과성숙률에 근거한 자율자가 수정지수(AI)와 자가화합성지수(SI)는 각기 0.33, 0.50이었다. ESP의 융설이 LSP보다 10일 빨랐고 이에 따라 ESP와 LSP의 개화수명과 계화계절이 현저한 차이를 보였으나 두 개체군의 개화절정일은 거의 차이가 없었다. 결론적으로, 소백산 아고산지역 모데미풀은 수분매개자 서비스를 통해 거의 타가수정으로 번식하는 조건부타가수정 식물이다. 또한 기후변화로 인한 융설 시점(이른 vs. 늦은)과 후속적인 개화특성의 변동은 이미 희귀식물인 모데미풀을 더욱 위협할 가능성이 있다.