In this study, the quality safety limit period of seven types of bakery bread was analyzed, and their use-by date was calculated. For evaluating product quality, storage conditions were set as 5, 15, 25, and 35oC for 50 days, and moisture, microorganisms, sensory characteristics, and dominant bacteria were examined. The quality and safety standards followed the Korea Food Code and Korean industrial standards (KS). The results showed that all products stored at 5oC satisfied the standard for bacterial count for day 50, but the sensory quality was below the standard level. Samples stored at 15oC showed high variability from 3–39 days. At 25oC, a quality safety limit period of 2–20 days was set, and one sample was found to have the same shelf life. Bread stored at 35 °C had the shortest quality safety limit period. Considering a safety factor of 0.87, a use-by date period of 1.7–13.1 days was calculated. Therefore, setting the use-by date according to the product type is necessary, even for the same product category. Among the bread products sold in bakeries, those managed as room temperature products (1–35oC) can be distributed and stored in a temperature range of up to 35oC. Overall, this study demonstrates the importance of setting a quality retention period based on the product characteristics and carefully considering the safety factor.

Porcine parvovirus (PPV), a member of the genus Parvovirus, family Parvoviridae, is a significant causative agent in porcine reproductive failure, causing serious economic losses in the swine industry. PPV is a non-enveloped virus and its capsid is assembled from three viral proteins (VP1, VP2, and VP3). The major capsid protein, VP2 is the main target for neutralizing antibodies in PPV. When VP2 was expressed in large amounts, it assembled into virus-like particles (VLPs) similar in size and morphology to the original virions. In this study, we generated the recombinant Bombyx mori nucleopolyhedrovirus (BmNPV) to express the VP2 protein. Expression of the VP2 protein was analyzed by SDS-PAGE and Western blot. The recombinant VP2 protein of approximately 64 kDa was detected by both analyses. The formation of VLP by recombinant VP2 was confirmed through transmission electron microscopy examination. The purified VP2 protein assembled into spherical particles with diameters ranging from 20 to 22 nm.

Historically the rise of contagious diseases and epidemics has been mainly caused by lack of food safety knowledge and negligence in personal hygiene. Food poisoning is an example that have been caused by lack of proper knowledge in food safety and personal hygiene. In order to prove this hypothesis, our team distributed a total of 225 survey sheets to middle school students. Survey questions mainly focused on the students' food safety knowledge, personal hygiene and regular dietary habits. We used 12 items to determine the stages of change in teenagers and divided into 3 stages of change: precontemplation stage (poor problem recognition), contemplation and preparation stage (some problem recognition), and action stage. Out of the 225 students surveyed, 105(47.1%) were male and 118 (52.9%) were female; 44.0% were in 7th grade, 33.0% in 8th grade, and 24.0% in 9th grade. In stages of change model, 3.8% were classified in pre-contemplation stage, 31.1% in preparation stage, and 65.1% in action stage. The awareness of the significance of food safety has a strong positive correlation with the stages of change food safety behavior (P<0.001), which suggesting our questionnaires regarding stages of change and food safety behavior were quite credential. Stages of change were also correlated with the consumption of unsanitary foods (P<0.01) and with the frequent hand washing (P<0.05). The stages of change showed a positive correlation with the food safety knowledge level (P<0.05). The four questions (out of 10) with the least percentage of correct answers were questions about the meaning of Norovirus (23.6%), the meaning of expiration date (43.6%), the meaning of food poisoning (36.4%), and proper food-handling (36.0%).

The bumblebee, Bombus ardens, is a valuable natural resource, and is most notably utilized for greenhouse pollination. In order to gain a greater understanding of the population genetic structure and the genetic diversity of this species, we sequenced a portion of the mitochondrial COI gene corresponding to the “DNA Barcode” region (658 bp) from 160 individuals collected over 15 Korean localities. Uncorrected pairwise distances among the eight haplotypes suggested low intraspecific genetic diversity, with a maximum sequence divergence of 0.3%. Such a low level of intraspecific genetic diversity was further reflected in local populations, particularly to islet populations, such as those of Youngheungdo, Jakyakdo, and Ulleugdo, which had zero genetic diversity. Geographically, one haplotype (BARBA01) was widespread and dominant, with a frequency of 90.6% (145 among 160 individuals). Other haplotypes were restricted to one to three localities and had low frequency. Overall, a very high rate of per generation female migration ratio (Nm= 4.6 to infinite) and a very low level of genetic fixation (FST= 0 to 0.099) were detected between pairs of localities, suggesting that the B. ardens population sonthe Korean peninsula are panmictic, which is consistent with our understanding of their dispersal capability.

To understand geographic genetic variation of the species and relationships among populations of the bumble bee, Bombus ardens, that is utilized as green house pollinator we expanded our investigation by sequencing somewhat longer mitochondrial DNA (mtDNA) fragment, covering some uninvestigated regions within the species distribution, and analyzing the sequence data in terms of population genetic structure. For the purpose of study, a portion of mitochondrial COI gene, corresponding to "DNA Barcode" region (658 bp) was sequenced from 160 individuals of B. ardens collected over 15 localities in Korea. The sequence data revealed overall relatively low genetic diversity within species, with a maximum sequence divergence of 0.3%. Geographically, one haplotype (BARBA01) was found in all localities surveyed, with the frequency of 91% (145 among 160 individuals), whereas other haplotypes were found in a locality mostly as a single individual, suggesting that haplotype distribution can be summarized as coexistence of widespread, one dominant haplotype and regionally restricted, other haplotypes. Overall, very high rate of per generation female migration (Nm = 4.6 ~ infinite) and very low level of geographic substitution (FST = 0 ~ 0.099) among localities were characteristic. Although some populations were genetically subdivided from the remaining localities in the hierarchical analysis, there was regional polarity on this subdivision. Taken together with gene flow estimates, the nature of genetic divergence of the bumble bee populations is characterized as one that possessing low genetic diversity, high gene flow, and wide spread of one dominant haplotype, consistent with the previous finding. To have further detailed information of this valuable genetic resource, further longer and variable molecular portion is under investigating.

To understand geographic genetic variation of the species and relationships among populations of the bumble bee, Bombus ardens, we sequenced a portion of mitochondrial COI gene, which corresponds to "DNA Barcode" region (658 bp) from 101 B. ardens individuals collected over 11 localities in Korea. The sequence data were used to investigate genetic diversity within populations and species, geographic variation within species, phylogeographic relationship among populations, and phylogenetic relationship among haplotypes. A total of nine haplortpes were found, but they very close to each other (a maximum sequence divergence of 0. 304%). Summarized, overall moderate to low genetic diversity within populations and species was characteristic, concordant with the high potential to disperse of B. ardens in Korea. There was no clear regional subdivision was observed and relatively high rate of gene flow among localities and low FST was characteristic.

이 연구는 동기화-지속 과제(synchronization-continuation task)를 수행할 때 발생하는 타이밍 제어 특성을 무용 숙련성과 템포의 측면에서 규명하는 데 목적이 있다. 방법: 연구참여자는 국내 직업무용단에서 활동하고 있 는 무용 숙련자 12명과 비숙련자 12명이다. 실험과제는 각기 다른 템포 조건(60, 120, 180bpm)에서 주기적으로 제공되는 청각자극에 맞춰 손가락 태핑(finger tapping)을 동기화하는 것과 청각자극 없이 기존 템포를 지속하며 태핑하는 것이다. 청각자극이 제시되는 동기화 과제에서 비동기성의 절대오차는 타이밍 정확성으로, 비동기성의 표준편차는 타이밍 가변성으로 산출하였다. 청각자극이 없는 지속 과제에서는 탭 간 간격(inter-tap interval, ITI)과 목표시간 간 차이를 타이밍 정확성으로, ITI의 표준편차는 타이밍 가변성으로 산출하였다. 결과: 동기화 과제에서 타이밍 정확성은 120bpm 조건에서 가장 높게 나타났고, 무용 숙련자의 타이밍 가변성은 비숙련자와 비교하여 60bpm, 120bpm 조건에서 유의하게 낮게 나타났다. 지속 과제에서 나타난 타이밍 가변성은 숙련자가 비숙련자보 다 낮게 나타났으며, 60bpm 조건에서 다른 템포 조건보다 높게 나타났다. 결론: 이러한 연구결과를 통해 무용 숙 련자는 주기적인 리듬에 맞춰 일관적으로 움직이는 것뿐만 아니라 청각자극 없이 규칙적인 움직임을 생성하고 유 지하는 데 특화되어 있으며, 오랜 무용훈련 경험이 이러한 능력을 촉진하는데 긍정적인 효과를 가져왔음을 짐작 할 수 있다.

목적: 본 연구는 아동의 운동발달 수준에 따른 손가락의 최대근력과 신경역학적 특성을 규명하기 위한 예비연구 이다. 방법: 아동의 운동발달 수준을 평가하기 위하여 경기도 S시 지역아동발달센터에서 모집한 초등학교 2-4학 년생 31명을 대상으로 Movement Assessment Battery for Children-2(MABC-2)를 실시하였다. 이 중 보호자와 아 동이 본 실험에 참여하는 것을 동의한 일반아동 8명과 운동발달 지연이 의심되는 아동 6명을 대상으로 힘 센서를 사용하여 각각 왼손, 오른손, 양손의 손가락 최대근력을 측정하였다. 측정된 최대근력을 통해 각 조건의 손가락 최대근력과 신경역학적 특성을 의미하는 수지독립성을 산출하였으며, 집단의 차이를 규명하기 위해 독립 t-검정 및 맨-휘트니 U 검정을 실시하였다. 결과: 운동발달에 지연이 의심되는 아동은 일반아동과 동일한 수준의 손가락 근력을 지녔다. 그러나 양손 간 수지독립성의 경우 운동발달 지연이 의심되는 아동의 비우세 손이 더 독립적으로 움직이는 특성을 보였다. 결론: 운동발달 지연이 의심되는 아동이 일반아동에 비해 소근운동기술이 부족 한 원인은 손가락 근력의 문제라기보다 손가락 힘을 발생시킬 때 나타나는 신경역학적 특성인 수지독립성의 차이에 따른 것으로 생각된다. 이러한 연구결과는 운동협응 능력이 부족한 아동들의 손가락 제어 기전을 이해하기 위 한 기초자료로 활용될 수 있을 것이다.

Purpose: We investigated changes of motor skills development in children with developmental coordination disorder (DCD) after participating 12-week intervention program to promote their fundamental motor skills. Methods: The movement assessment battery for children-2 (MABC-2) was used to screen DCD. Ten children with DCD participated voluntarily in an after-school program 3 times per week for 12 weeks and were examined using the MABC-2 before and after the intervention. The program was planned to facilitate fundamental gross motor skills based on physical education curriculum for public school and their daily life. Results: After the intervention program, DCD children showed a significant improvement in aiming and catching, and balance. The total percentile score of DCD children after the intervention was significantly improved and marked higher than 16%, thereby indicating an improvement in their motor development after the program. Conclusion: This current study supports possibility to improve motor coordination of children with DCD with respect to fundamental motor skills. 12-week intervention might be effective to increase their score of MABC-2 from motor delay level to typically developing level.

Purpose: The purpose of the present study was to investigate the effect of different types of practice on badminton skill in elementary school student during practice with observation learning, repeated reading and mixed practice combining observation learning and repeated reading. Methods: Thirty-six 5th grade male elementary students participated and were randomly assigned into four different groups; control, observation learning(OL), repeated reading(RR), and mixed model(MD). Before performing the striking skill, they observed the badminton expert’s performance three times in real time. They were asked to peform high clear striking as a badminton skill 20 times at pre-test, practice, retention(RT) and delayed retention(DR). During intervention, control group watched video clips not related badminton, OL was asked to watch the video containing the expert performance in saggital view, RR was required to read the customized reading material, and MD watched the expert’s video and read the reading material. Results: There was significant difference in performance score between pre-test, RT, DR in MD. Conclusion: The current results suggest that MD seems more effective practice to learn badminton skill for male elementary school student.

Purpose: Postural stability has an important role for developing locomotion skills, especially in childhood. The purpose of this study was to investigate the developmental change of postural stability with respect to locomotor skills. Methods: Thirty-five participants aged between five to seven year-old whom differentiated by pre examination were divided into Jumping, Hopping, Galloping and Skipping group, respectively. They were asked to perform quiet standing and leaning voluntarily forward, backward, left and right as far as possible on a force plate. A vector of center of pressure was measured to calculate postural stability and one-way ANOVA was performed. Results: Jumping group showed significant low postural stability than the others and there is no significant difference among Hopping, Galloping, and Skipping group who can perform advanced locomotor skills. Conclusion: Postural stability seems to increase when children acquire advance locomotor skills and this result might reflect nonlinear characteristic of human motor development.