In Hymenoptera, thanks to its haplodiploid sex determination, arrhenotokous parasitoid females are able to control offspring sex ratio by determining whether to use sperm or not at the time of oviposition. However, the offspring sex ratio may also be influenced by the mating behavior of a male. When a male searches females, he will have more chances to encounter with other males in a high male density population than low male density population. If the male is competitive, the male can find females faster and may have longer copulation time, and eventually transfer more sperm than other males. In this study, we investigated mate searching time, copulation duration and offspring sex ratio as a function of the male density. Although the results show difference between searching time and copulation duration, they are not statistically significant. We will discuss the statistical consequence, male density dependent offspring sex ratio and its evolutionary implications.

In Korea, twelve species in genus Myrmica have been described. Some of them are morphologically similar and this makes their identification difficult. For this reason, we collected several Myrmica species in question and inferred their phylogenetic relationship using the 418bp partial COI (cytochrome C oxidase 1) region from a total of 33 individuals. We found that the CO1 haplotypes are effectively grouped into three clusters that match well to their external morphological characters. Although this three species could be distinguished by the only small part of the COI region, the two individual sample of the M. kotokuii and one sample of the M. carinata are included in the M. kurokii group. The results indicate that the morphological identification could be obscure in the three species and it requires a close examination for this phenomenon.

The brown marmorated stink bug Halyomorpha halys Stål (Hemiptera: Pentatomidae), is native to Korea, Japan, and China. H. halys is one of the major polyphagous pentatomids with a wide host range encompassing ornamental shrubs, trees, and cultivated crops such as millet, sesame, soybean, apple, yuzu, pear, cherry, and peach and inflicting losses of several crops in Korea. However, study on dietary importance of these hosts on the development rate of H. halys is sparse. We evaluated fruits of apple and orange with or without soybean plus peanuts as food sources to investigate development rate, mortality and fecundity of the stink bug. Not apple but orange only diet could support development up to adult stage but with higher mortality. First instars were found to molt into second instars without feeding. The longest time H. halys took to develop was in its fifth instar. Overall shortest developmental period (39.82) days was recorded on those fed on orange+soybean and peanut whereas those fed on orange only diet had longest development period (78.92 days). Generational mortality of those fed on diets consisting of soybean and peanuts ranged from 43 to 53%. Those only fed on water could not develop into third instars. H. halys could not develop into fourth instar in apple only diet. However, on orange only diet 20% H. halys could emerge as adults. Fecundity was measured for the first day of oviposition per female. Fecundity was recorded highest (28 eggs) on orange+soybean and peanut diets. The results suggest that H. halys require leguminous seeds in order to develop fully and lay fertile eggs.

2010년부터 2012년까지 밀양, 괴산, 원주의 잡곡포장에 성페로몬트랩을 설치하 여 5월부터 10월까지 조명나방, 담배거세미나방 등 나방류 6종의 유인량을 조사하 였다. 지역간 나방류의 발생량은 밀양에서 총 5,520마리로 원주 및 괴산보다 각각 11.7배 및 8.2배 많았다. 밀양에서 담배거세미나방의 발생비율은 72.1%로 다른 나 방류 및 지역보다 월등히 높았으며, 그 다음은 파밤나방(12.9%) 이었으나, 멸강나 방은 0.4%로 매우 낮았다. 괴산에서 담배거세미나방의 발생비율(39.5%)이 가장 높았고, 그 다음은 담배나방(28.9%) 및 파밤나방(11.9%)의 순서 이었으며, 멸강나 방은 1.7%로 매우 낮았다. 원주에서 담배거세미나방의 발생비율(33.2%)이 가장 높았고, 그 다음은 담배나방(25.4%) 및 왕담배나방(15.9%)의 순서 이었고, 멸강나 방 발생비율은 0.7%로 매우 낮았다. 담배거세미나방의 발생최성기는 지역에 따라 차이가 있었으나, 대체로 9월 상순∼9월 하순까지로 나타났고, 밀양에서 담배거세 미나방은 10월 하순까지도 발생량이 매우 많았다. 파밤나방의 발생최성기는 지역 에 따른 차이가 심하였는데, 밀양은 8월 하순∼9월 중순, 괴산은 9월 중순∼10월 상 순, 원주는 9월 상순∼9월 중순까지로 나타났다. 조명나방의 발생최성기는 지역에 따른 큰 차이 없이 6월 상순∼6월 중순까지로 나타났다. 멸강나방의 발생최성기도 지역간 차이 없이 5월 중·하순 이었으나, 다른 나방류에 비해 발생량은 매우 적었 다. 왕담배나방의 발생최성기는 지역별 차이가 매우 심하였는데, 밀양은 9월 상순 ∼9월 중순, 괴산은 8월 상순∼8월 하순, 원주는 6월 상순∼6월 중순까지로 나타났 다. 담배나방의 발생최성기는 밀양에서 8월 상순∼8월 하순, 괴산에서 7월 하순∼8 월 중순, 원주에서 8월 하순∼9월 상순으로 지역에 따른 차이가 있었다. 이처럼 지 역별 나방류 발생량과 발생최성기의 차이는 나방류의 생물적 특성, 지역별 기상, 재배작물의 면적, 작부양식 및 체계와 관련이 있는 것으로 여겨진다.

Wolbachia is one of the most common endosymbionts best known to induce several reproductive alterations in its insect hosts. In some cases, the insect hosts harbor more than two strains of the bacterium. The Vollenhovia emeryi ant lives in dead trees and is morphologically subdivided into the long-winged and the short-winged. Interestingly the short-winged morph is free of Wolbachia, but only the long-winged morph is multiple- infected with the Wolbachia bacterium. We sampled four populations of the long-winged morph in Korea and performed pyrosequencing in Multilocus Sequence Typing (MLST), to determine the bacterial strain diversity. Six different gene regions (coxA, fbpA, ftsZ, gatB, hcpA and wsp gene) were targeted and amplified. However, the result shows that diversity of haplotypes is very high. The pyrosequencing approach in MLST, a new method of discriminating Wolbachia strains, is promising to effectively detect multiple infections and rare haplotypes.

The hologenome theory of evolution proposes that an organism is simply not an individual but the totality of numerous microbial symbionts to the host. In fact, the evidence of biochemical and physiological associations between the symbionts and the host has been growing fast in all major taxa. The Vollenhovia emeryi ant is tiny and found nationwide in Korea. The ant can be further categorized by its wing morphology, eg. long-winged and short-winged. Our initial screening process showed that the microbial reproductive manipulator, the Wolbachia bacterium, only infected the long-winged morph. This gave us a good opportunity to investigate the effect of the Wolbachia infection on the bacterial community diversity using the next generation sequencing technique. We find that there are about 180 bacterial symbionts in the short-winged morph. On the other hand, the long-winged morph has only about 20 bacterial symbionts. This implies that the bacterial community diversity may be subject to the existence of Wolbachia. Furthermore, the Wolbachia strain diversity is unexpectedly high. In addition, the bacterial structure difference among castes indicates that there may be labour division even between queens. The results and future research direction will be discussed from the hologenome theory perspective.

Riptortus pedestris (F.) inflict losses on a wide range of crop plants. Biological control is an alternative approach to reduce the bean bug population. Scelionid Gryon japonicum (Ashmead) and Encyrtid Ooencyrtus nezarae Ishii are the major egg parasitoids of R. pedestris. The aggregation pheromone of R. pedestris serves as a kairomone to its egg parasitoids. A new tool was developed using aggregation pheromone in a trap which attracts both con-specific bugs and the parasitoids. Non viable host eggs were added with the trap so as to provide resource for the attracted parastioids to multiply. Several studies were conducted to develop this new tool for trapping of the bugs and enhancing parasitism simultaneously. Aggregation pheromone trap added with host eggs was found to increase temporal parasitism in field by 44% compared to the parasitism without host eggs. Higher parasitism (up to 91%) was found in the sites where aggregation pheromone trap added with host eggs was installed compared to control sites. In order to improve this tool, a new device with twelve sections to hold eggs and to be attached to the pheromone trap was designed to provide maximum exposure of the eggs to the parasitoids and to minimize the competition among the parasitoids. Parasitism and number of female R. pedestris trapped in new device attached trap were higher compared to the conventional. With better performance in trapping R. pedestris and enhancing parasitism, the tool would serve as an IPM technique that targets killing the pest and enhancing activity of the pest’s natural enemy simultaneously.

We investigate the dependence of the extended X-ray emission from the halos of optically luminous early-type galaxies on the small-scale (the nearest neighbor distance) and large-scale (the average density inside the 20 nearest galaxies) environments. We cross-match the 3rd Data Release of the Second XMMNewton Serendipitous Source Catalog (2XMMi-DR3) to a volume-limited sample of the Sloan Digital Sky Survey (SDSS) Data Release 7 with Mr < −19.5 and 0.020 < z < 0.085, and find 20 early-type galaxies that have extended X-ray detections. The X-ray luminosity of the galaxies is found to have a tighter correlation with the optical and near infrared luminosities when the galaxy is situated in the low large-scale density region than in the high large-scale density region. Furthermore, the X-ray to optical (r-band) luminosity ratio, LX/Lr, shows a clear correlation with the distance to the nearest neighbor and with large-scale density environment only where the galaxies in pair interact hydrodynamically with seperations of rp < rvir. These findings indicate that the galaxies in the high local density region have other mechanisms that are responsible for their halo X-ray luminosities than the current presence of a close encounter, or alternatively, in the high local density region the cooling time of the heated gas halo is longer than the typical time between the subsequent encounters.

In this study, a theoretical investigation of optimized sleeper spacing which can suppress resonances of a railway track is attempted. To achieve this, we introduced a minimization problem in which the objective function is given by the wave transmittance and the design variable is defined by sleeper distribution. In the analysis the rail is modeled by a Timoshenko beam and the sleeper is represented by a mass. The infinite track analysis is realized by attaching the transmitting boundaries at both ends of the finite optimization region. Through numerical analyses the sleeper spacing effective in reduction of the transmittance is discussed. Furthermore, the feasibility of the proposed method is validated in the aspect of vibration reduction through response analyses for a harmonic load.

In this study, the in vitro fermentation parameters of whole crop barley (WCBS-TMR) and Italian ryegrass (IRGS-TMR) silage total mixed rations were compared. A rice straw based diet (RSBD), which was a mixture of rice straw and concentrate (60:40), was used as the control. The feeds were incubated in buffered rumen fluid for 3, 6, 9, 12, 24, 48 and 72 hours at 39°C. At the end of each incubation period the following parameters were determined, total gas, pH, ammonia nitrogen (NH3-N), volatile fatty acids (VFA) and then the acetate to propionate ratio (A/P) was calculated. The dietary treatments did not affect (p>0.05) the overall production of NH3-N, gas, total VFA and all the individual VFA, with the exception of n-butyrate (p<0.001). The treatment diets significantly affected the A/P ratio (p<0.01). The control diet resulted in the lowest A/P ratios, followed by WCBS-TMR and lastly IRGS-TMR had the highest ratios. Gas production was not different between treatments, suggesting a probable similar level of digestibility when treatments are fed to animals. It can therefore be concluded from the present study that WCBS and IRGS are of almost an equivalent nutritional value when incubated in a TMR form. WCBS-TMR however resulted in lower A/P ratios than IRGS-TMR, which is indicative of a more energy efficient diet.

Lactic acid bacteria (LAB) are known to promote activation of macrophages, selectively eliminate harmful intestinal bacteria that enter the body, and increase secretion of cytokines, chemokines, and inflammatory mediators that boost the immune system. In the current study, the immune-enhancing effects of five Leuconostoc stains (Leu. kimchii WK18, Leu. citreum DH33, Leu. mesenteroides DH34, SE34, and GY17) isolated from traditional Korean fermented food, Kimchi, were evaluated. Lactobacillus rhamnosus GG (LGG), which is known for its extraordinary immunopotentiating activity, was used as a reference strain. According to the results, several heat-killed Leuconostoc strains induced a higher level of NO, IL-1β, or TNF-α production than the LGG strain. Collectively, results of the current study suggest that Leuconostoc strains could enhance immune response through activation of macrophages, and could be significant references when verifying the possibility for use of Leuconostoc strains as probiotics, starter, dietary supplement, or immune-enhancing medicine.

화학합성 농약을 대체하기 위한 친환경 방제법 개발을 위해 1, 2, 4%의 도꼬마리 열매 수용성 추출물을 이용하여 팥바구미 살충력을 실험하였다. 실험한 추출 농도에서 곤충 치사율, 기피성, 산란율과 성충 우화 및 팥의 피해 억제에 효과를 보여 주었다. 4%의 추출물은 처리 후 2일 후에26%의 치사율과 처리 후 3시간에 53.3%의 기피율을 각각 보였다. 또한 4%의 추출물을 팥과 섞었을 때 가장 낮은 산란율(113.7/암컷)과, 성충 우화율이 가장 많이 억제(37.0%)되었고 종자 손상을 가장 적게(42.3%) 받았다. 이러한 결과는 도꼬마리 추출물이 저장곡물을 팥바구미로부터 보호하는 종합적 방제수단으로 사용될 수 있다.

Since the Free Trade Agreements (FTAs) with Chile, the EU, and the U.S., Korean agricultural produce markets have turned into a fierce competition landscape. Under these competitive circumstances, marketing is critical. The objective of the research presented herein is to understand the characteristics of customer preferences after locating trends of purchased items. So This research establishes sustainable strategies for Korean agricultural produce. This investigation used market-basket analysis techniques and panel data for its research. Market-basket analysis is a technique which attempts to find groups of items that are commonly found together. The results show that, for one year, processed food using wheat, processed marine products, and pork are commonly bought together and that yogurt and milk also are bought together. The characteristics of customers buying these items are 44 years old and live in a four-person household with two children. These customers do not live with their parents.

The purpose of this study was to identify the effects of tensor fasciae latae-iliotibial band (TFL-ITB) self-stretching exercise on the lumbopelvic movement patterns during active prone hip lateral rotation (HLR) in subjects with lumbar extension rotation syndrome accompanying TFL-ITB shortness. Eleven subjects (9 male and 2 female) were recruited for the two-week study. A three dimensional ultrasonic motion analysis system was used to measure the lumbopelvic movement patterns. The TFL-ITB length was measured using the modified Ober's test and was expressed as the hip horizontal adduction angle. The subjects were instructed how to perform TFL-ITB self-stretching exercise program at home. A paired t-test was performed to determine the significant difference in the angle of lumbopelvic rotation, movement onset time of lumbopelvic rotation, TFL-ITB length, and LBP intensity before and after the two-week period of performing the TFL-ITB self-stretching exercise. The results showed that after the intervention, the lumbopelvic rotation angle decreased significantly (p<.05), the movement onset time reduced significantly (p<.05), and LBP intensity decreased slightly but not significantly (p=.07). The hip horizontal adduction angle increased significantly (p<.05) after the intervention. These findings indicate that TFL-ITB stretching exercise increased TFL-ITB length, decreased lumbopelvic rotation angle, and delayed the movement onset time of lumbopelvic rotation after two-weeks. In conclusion, the TFL-ITB self-stretching exercise performed over a period of two weeks may be an effective approach for patients with lumbar extension rotation syndrome accompanying TFL-ITB shortness.

The aim of this study is to compare the effect of abdominal drawing-in maneuver (ADIM) on lower trapezius (LT), serratus anterior (SA), and erector spinae (ES) muscle activity during arm lifts in prone and standing positions. Twenty healthy subjects were recruited, and NoraxonTeleMyo 2400T was used to collect electromyographic signals from the LT, SA, and ES muscles. A two-way repeated analysis of variance (ANOVA) used a significance level of .05. If a significant interaction was found, pairwise comparisons were performed with a Bonferroni adjustment (.05/4=.013). The results of the study were as follows: 1) In LT, no significant ADIM by position interaction was found (=.356, p=.558). There was a significant main effect for ADIM. LT muscle activity with ADIM was significantly greater compared with muscle activity without ADIM (=82.863, p<.001). There was also a significant main effect for position. LT muscle activity in the prone position was greater compared with muscle activity in the standing position (=116.401, p<.001). 2) In SA, significant ADIM by position interaction was found (=8.687, p=.008). There were significant differences in all pairwise comparisons. The greatest SA muscle activity was observed in the standing position with ADIM. 3) In ES, significant ADIM by position interaction was found (=122.473, p<.001). The lowest ES muscle activity was elicited in the standing position with ADIM. Based on these results, ADIM is advocated in the prone position to increase LT muscle activity. In addition, it is concluded that arm lifts in the standing position with ADIM offer the most favorable combination for reducing ES muscle activity and increasing SA muscle activity.

The present study purposed to examine the effects of transcutaneous electrical nerve stimulation, self-stretching and functional massage on the recovery of muscle contraction force for muscle fatigue caused by sustained isotonic contraction. The subjects of this study were 45 healthy students. They were divided into transcutaneous electrical nerve stimulation group(n=15), self-stretching group(n=15) and functional massage group(n=15), and using Primus RS. We observed the pattern of changes in maximal voluntary isometric contraction force(MVIC) after causing muscle fatigue in quadriceps femoris muscle through sustained isotonic contraction. Maximal voluntary isometric contraction force(MVIC) were greatly increased after transcutaneous electrical nerve stimulation, self-stretching and functional massage. In the comparison of recovery rate of muscle contraction force for muscle fatigue caused by sustained isotonic contraction among the treatment groups, it did not show any significant differences. However, it showed that each treatment may be effective in recovery of muscle fatigue caused by sustained isotonic contraction.