This study investigates the phenomenon of task specialization in subterranean termites, focusing on their tunneling behavior. Termites, known for their complex social structure, allocate specific individuals for tunnel construction, rarely switching tasks. To explore this behavior, we developed a simulation model comparing termite groups with and without task shifts. While tunnel orientation showed no significant difference between the two tunnel pattern groups, the absence of task shifts resulted in larger tunnels, indicating enhanced foraging efficiency. This suggests that maintaining a consistent division of labor without task rotation benefits termite foraging. This study sheds light on the ecological advantages of task specialization in social insects, highlighting its role in foraging success and colony survival.

From an evolutionary perspective, it is speculated that termites have evolved to construct tunnels in a manner that optimizes search and transport efficiency. While numerous studies have focused on search efficiency, there has been limited research on transport efficiency due to the challenges associated with direct field observations. To address this challenge, we developed an individual-based model to simulate the transport process. Using the model, we examine the effects of several key variables on transport efficiency, Based on our results, we discuss potential strategies that termites might employ to optimize transport efficiency. In addition, we briefly discuss ways to improve the realism of the model.

Measurement of the physical properties of high-temperature molten salts is important for the efficient design and operation of molten salt reactors (MSR) in which the reactor coolant and nuclear fuel are in a homogeneous liquid state. Although some crucial physical properties such as viscosity, thermal conductivity, density, etc., have been drawing much attention, relative data, especially for molten chloride salts, are scarce. Thus, it is urgent to prepare the viscosity data as one of the key transport properties in thermal hydraulics analysis. However, it is not an easy task to measure the molten salt viscosity with high accuracy due to end effect, a small gap between the chamber and spindle, thermal expansion of the chamber and spindle at high temperatures in a rotational viscometer. Additionally, molten salt temperatures inside furnace are not uniform due to the large temperature gradient inside the chamber, and therefore the assumption of laminar condition can be violated. In this study, geometric factors, which can be a major interference in the torque measurement, were considered for the accurate determination of the viscosity. We established a high-temperature molten salt viscosity measurement system with Brookfield rotational viscometer. KNO3 molten salt was used as a model substance at a temperature range of 650–773 K. In-house designed spindles and chambers were made of corrosion-resistant alumina. Thermal expansion has a significant influence on the size and shape of the chamber and spindle. The effect of thermal expansion on the conventional correction method was examined with temperature variation and distribution. Gap size variation was also investigated in order to improve the accuracy.

The purpose of this study was to create a theoretical structure for the concept of purchasing risks by identifying the structure of purchasing risks that lead to obstacles in the purchasing decisions of consumers in fashion consumption via online channels. This was a secondary research using books, articles, prior researches, and academic journals on the five topics of “characteristics of fashion consumption,” “the concept of purchasing risks,” “purchasing risks by product types,” “purchasing risks by channel types,” and “purchasing risks of fashion consumption on online shopping channels.” According to the arguments of prior researches, the study divided the purchasing risks of fashion consumption through online shopping into four categories : (1) fundamental purchasing risks including financial risk and time loss risk pertaining to any product or channel, (2) online channel purchase risks, which include risks in payment, Information leaks, and delivery and return/exchange risk, (3) fashion product risk related to product quality or experience of other people, which includes social risks and risks associated with quality, and (4) the online channel×fashion product risks, which include the aesthetic and psychological hazards especially amplified in online channels. The four risk factors were then described with a concept map to systemize the multidimensional and stereoscopic psychological structure of purchasing risks. Of the four risk factors, consumers placed the most emphasis on the online channel×fashion product risks, hence, reducing this risk factor is of utmost priority for marketing of online shopping channels.

In this study we present a new approach to estimating termite populations size. So far, termite researchers have been using the mark-capture-recapture method. This method has a disadvantage that measurement time is long and error range is large. To this end, we built an agent-based model to simulate termite tunneling behavior. Using this model, we made simulated tunnel patterns that are determined by three variables: the number of simulated termites (N), the passing probability of two encountering termites (P), and the distance that termites move soil parcels (D). To explore whether the N value can be estimated with a partial termite tunnel pattern, we generated four groups of tunnel patterns that are partially obscured in complete tunnel pattern image: (1) A pattern group in which the outer area of the tunnel pattern is obscured (I-pattern), (2) a pattern group in which half of the tunnel pattern is obscured (H-pattern), (3) a pattern group in which the inner region of the tunnel pattern is obscured (O-pattern), and (4) a pattern group combining I- and O-pattern (IO-pattern). For each group, 80% of the tunnel patterns were learned through a convolution neural network (CNN) and the remaining 20% of the patterns were used for estimating N value. The estimation results showed that the N estimates for the IO-pattern are the most accurate and are in the order I-, H-, and O-patterns. This means that the termite population size can be estimated based on tunnel information near the center of the colony.

본 연구는 수분함량 22, 25, 28%, 스크루 회전속도 200, 250 rpm, 용융물 온도 110, 120, 130℃의 조건범위로 조절하고 원료 사입량 100 g/min으로 고정하여 압출 성형한 밤과육의 물리적 특성(직경 팽화율, 비길이, 체적밀도), 수분용해지수 및 수분흡착지수, 환원당 함량과 항산화 활성에대해 분석하였다. 밤 압출성형물은 직경 팽화율이 증가할수록 비길이와 체적밀도는 감소하였고, 수분용해지수와 수분흡착지수는 수분함량이 낮아질수록 증가하였다. 압출성형을 통하여 환원당 함량, DPPH 라디칼 소거능, 총 페놀함량 및 플라보노이드 함량은 감소하였으며, 탄닌함량은 압출성형을 통해 2.94±0.10−4.23±0.12 mg/g 범위로 낮아지는 경향을 나타내었다. 결론적으로 압출성형 후 수분용해지수의 증가는 밤 음료의 용해도 개선의 효과를 나타낼 수 있으며, 또한 압출성형공정은 소비자 기호성에 영향을 미치는 탄닌의 쓴맛을 감소시키는 가능성을 제시하였다. 이를 통해 다양한 식품의 중간소재로써 압출성형 밤이 활용 될 수 있다고 판단된다. 밤의 식품중간소재 기초자료로서 응용될 것으로 생각되지만, 압출성형 최적조건을 보다 효과적으로 도출하기 위한 연구가 필요할 것으로 판단된다.

본 연구는 수분함량 22, 25, 28%, 스크루 회전속도 200, 250 rpm, 용융물 온도 110, 120, 130℃의 조건범위로 조절하고 원료 사입량 100 g/min으로 고정하여 압출 성형한 밤과육의 물리적 특성(직경 팽화율, 비길이, 체적밀도), 수분용해지수 및 수분흡착지수, 환원당 함량과 항산화 활성에 대해 분석하였다. 밤 압출성형물은 직경 팽화율이 증가할수록 비길이와 체적밀도는 감소하였고, 수분용해지수와 수분흡착지수는 수분함량이 낮아질수록 증가하였다. 압출성형을 통하여 환원당 함량, DPPH 라디칼 소거능, 총 페놀함량 및 플라보노이드 함량은 감소하였으며, 탄닌함량은 압출성형을 통해 2.94±0.10−4.23±0.12 mg/g 범위로 낮아지는 경향을 나타내었다. 결론적으로 압출성형 후 수분용해지수의 증가는 밤 음료의 용해도 개선의 효과를 나타낼 수 있으며, 또한 압출성형공정은 소비자 기호성에 영향을 미치는 탄닌의 쓴맛을 감소시키는 가능성을 제시하였다. 이를 통해 다양한 식품의 중간소재로써 압출성형 밤이 활용 될 수 있다고 판단된다. 밤의 식품중간소재 기초자료로서 응용될 것으로 생각되지만, 압출성형 최적조건을 보다 효과적으로 도출하기 위한 연구가 필요할 것으로 판단된다.

Artificial insemination technique has been contributed immensely for production of livestock worldwide as a critical assisted reproductive technique to preserve and propagate excellent genes in domestic animal industry. In the past decade, methods for semen preservation have been improved mostly in liquid preservation method for boar semen and freezing method for bull semen. Among many factors affecting semen quality during preservation, reactive oxy-gen species, produced by aerobic respiration in sperm for survival and motility, are unfavorable to sperm physiology. In mammalian cell as well as in the sperm, antioxidant system plays a role in degradation of reactive oxygen species. Magnetized water forms smaller stabilizing water clusters, resulting in high absorption and permeability of the cell for water, implicating its application for semen preservation. Therefore, this review focuses on preservation methods of boar and bull semen with respect to improvement of extender and reduction of reactive oxygen species by using magnetized water and supplementation of antioxidants.

Previously, we performed de novo RNA sequencing of Scolopendra subpinipes mutilans using high-throughput sequencing technology and identified several AMP candidates. Among them, a synthetic peptide (CP112) was designed based on the physicochemical properties of antimicrobial peptide such as length, charge, isoelectric point. Here, we have assessed the antimicrobial activities of CP112 against various microbes and the antioxidative effects. The results showed that CP112 had antimicrobial activities in radial diffusion assay and colony count assay. In addition, we found that CP112 bound to the surface of microorganisms via a specific interaction with lipoteichoic acid, lipopolysaccharide and peptidoglycan, which is one of bacteria cell wall components. Furthermore, CP112 has shown significant DPPH radical scavenging activity. Taken together, the results would be provided the basis for developing of peptide antibiotics and antioxidants.

Subterranean termites build extensive underground galleries consisting of elaborate tunnels and channels to forage food resources. Diverse soil conditions surrounding the tunnels, such as soil density, may cause irregularities in the size and shape of the tunnels, and termites are likely to encounter a number of tunnel irregularities while traveling. Considering the tunnel length, how termites respond to an irregularity is likely to affect their movement efficiency, and this in turn is directly correlated to their foraging efficiency. To understand the response of termites, we designed an artificial linear tunnel with rectangular irregularities in a 2-D arena. The tunnel widths, W, were 3 and 4 mm. The rectangular irregularities were 2 mm in width and of varying heights H (2, 1, 0, -1, and -2 mm). The positive and negative sign of H represents a convex and concave structure, respectively. We systematically observed the movement of termites, Coptotermes formosanus Shiraki, at the irregularity and quantified the time needed, τ, for a termite to pass the irregularity. The time τ was shorter for (W, H) = (3, 0) and (3, -1) than for (W, H) = (3, 1), (3, 2), and (3, -2). The time τ was longer for (W, H) = (4, -1), and (4, -2), than for (W, H) = (4, 0), (4, 1) and (4, 2). Four types of behaviors explained the response to the irregularity. The implications of these findings are briefly discussed in relation to termite foraging efficiency.

Understanding the predator-prey dynamics is essential to comprehend the ecosystem resilience and stability because ecosystems consist of dynamically interacting subsystems with predator-prey relationship. The relationship is likely to be of the predator and prey hunting-escaping strategy. Thus, to better understand the ecosystems, we should comprehend how the hunting and the escaping strategy affect the ecosystems. To do so, we constructed a spatially explicit lattice model to simulate the integrative predator-prey-plant relationships. When an individual simultaneously encounters its predator and/or prey, the individual should take priority between the two strategies. When the hunting (or escaping) strategy takes priority, we call it hunting preferred strategy, HPS, (or escaping preferred strategy, EPS). Each strategy was characterized by the willingness for each strategy. The degree of willingness was represented as H (for hunting) and E (for escaping). Higher value of H (or E) means stronger willingness for hunting (or escaping). We investigated the population density of each species for different values of H and E for HPS and EPS. The main conclusion that emerges from this study was that HPS plays a positive role in the ecosystem stability. In addition, we briefly discussed the development of the present model to be used to understand the predator-prey interaction in specific species.

The purpose of this study was to identify U.S. consumers' preferences for Bibimbap and to determine whether or not Bibimbap can be adopted into the American palate. A total of 214 people tasted a controlled amount of Bibimbap and Gochujang sauce (red chili pepper sauce) and then completed a preference test. Bibimbap was highly rated overall in the areas of appearance, color, smell, and taste. Gochujang sauce was also well-accepted in terms of taste and spiciness. Most of the participants disliked the seaweed and shiitake mushrooms, which means that Bibimbap can improve its garnish taste and aroma by removing them. Further, a more watery sauce was served as foreigners are not familiar with mixing food culture. Therefore, by offering diverse ingredient options, the acceptance of traditional Bibimbap can be increased in the U.S.

Subterranean termites construct underground tunnels, tens to hundreds of meters in length, in order to search for and transport resources. Diverse soil conditions surrounding the tunnels, such as soil pores and differing moisture concentrations, may cause different sized- and shaped-irregularities in the tunnels. To understand how individual termites respond to the irregularities, the present study monitored the movement of termites, Coptotermes formosanus Shiraki, in artificially excavated tunnels with rectangular irregularities of varying sizes in twodimensional sand substrates. Termites tunneled at some of the irregularities and not at the others. The tunneling or non-tunneling behavior resulted from four different responses. The non-tunneling response may result from a behavioral adaptation that allows termites to avoid wasting energy that may be used in foraging.

Partial mesophase (PM) pitch precursor was prepared from fluidized catalytic cracking-decant oils (FCC-DO) by chemical reaction in the presence of Br2. The PM pitch heated-treatment at 420℃ for 9 h exhibited the softening point of 297℃ with 23% yield, and 55% anisotropic content. The PM pitch precursor was melt-spun through circular nozzle by pressurized N2, stabilized at 310℃, carbonized at 700℃, 1000℃, and 1200℃. The enough stabilization introduced 16.4% of the oxygen approximately. The stacking height (Lc002) and interlayer spacing (d002) of the as-spun fibers were 4.58 nm and 3.45a and the value became minimum and maximum at 700℃ respectively in the carbonization procedure. The tensile strength increased with an increase in the heat treatment temperature exhibiting highest value of 750 MPa at 1200℃ carbonization.