• Animal Bioscience
• /
• v.35 no.7
• /
• pp.1100-1108
• /
• 2022

Objective: The objective of this study was to evaluate the effect of waste cooking oil (WCO) addition on ammonia (NH₃) emissions during the composting of dairy cattle manure under two aeration conditions. Methods: The composting tests were conducted using the laboratory-scale composting apparatuses (14 L of inner volume). Three composting treatments (Control, WCO1.5, and WCO3, with WCO added at 0 wt%, 1.5 wt%, and 3 wt% of manure, respectively) were performed in two composting tests: aeration rate during composting was changed from 0.55 to 0.45 L/min in Test 1, and fixed at 0.3 L/min in Test 2, respectively. The NH₃ emitted and nitrogen losses during the composting were analyzed, and the effect of the addition of WCO on NH₃ emissions were evaluated. Results: Both tests indicated that the composting mixture temperature increased while the weight and water content decreased with increasing WCO content of the composting mixtures. On the other hand, the NH₃ emissions and nitrogen loss trends observed during composting in Tests 1 and 2 were different from each other. In Test 1, NH₃ emissions and nitrogen losses during composting increased with increasing WCO contents of the composting samples. Conversely, in Test 2, they decreased as the WCO contents of the samples increased. Conclusion: The WCO addition showed different effect on NH₃ emissions during composting under two aeration conditions: the increase in WCO addition ratio increased the emissions under the higher aeration rate in Test 1, and it decreased the emissions under the lower aeration rate in Test 2. To obtain reduction of NH₃ emissions by adding WCO with the addition ratio ≤3 wt% of the manure, aeration should be considered.

• Molecules and Cells
• /
• v.45 no.10
• /
• pp.695-701
• /
• 2022

Homeostatic regulation of meristematic stem cells accomplished by maintaining a balance between stem cell self-renewal and differentiation is critical for proper plant growth and development. The quiescent center (QC) regulates root apical meristem homeostasis by maintaining stem cell fate during plant root development. Cell cycle checkpoints, such as anaphase promoting complex/cyclosome/cell cycle switch 52 A2 (APC/C^CCS52A2), strictly control the low proliferation rate of QC cells. Although APC/C^CCS52A2 plays a critical role in maintaining QC cell division, the molecular mechanism that regulates its activity remains largely unknown. Here, we identified SCF^FBS1, a ubiquitin E3 ligase, as a key regulator of QC cell division through the direct proteolysis of CCS52A2. FBS1 activity is positively associated with QC cell division and CCS52A2 proteolysis. FBS1 overexpression or ccs52a2-1 knockout consistently resulted in abnormal root development, characterized by root growth inhibition and low mitotic activity in the meristematic zone. Loss-of-function mutation of FBS1, on the other hand, resulted in low QC cell division, extremely low WOX5 expression, and rapid root growth. The 26S proteasome-mediated degradation of CCS52A2 was facilitated by its direct interaction with FBS1. The FBS1 genetically interacted with APC/C^CCS52A2-ERF115-PSKR1 signaling module for QC division. Thus, our findings establish SCF^FBS1-mediated CCS52A2 proteolysis as the molecular mechanism for controlling QC cell division in plants.

• The Journal of the Acoustical Society of Korea
• /
• v.40 no.3
• /
• pp.183-191
• /
• 2021

A time-series variation of temperature, salinity, and underwater sound speed was analyzed using an Array for Real-time Geostrophic Oceanography (ARGO) float which autonomously collects temperature and salinity for about 10month with 2 days cycle among 12 floats in the center of the Yellow Sea. As a result, the underwater sound channel appeared below the thermocline as the surface sound channel, which is dominant in the winter season, reduced in April. Besides, for a certain time in the spring season, the sound ray reflected the sea surface frequently due to the short-term temperature inversion effect. Based on the case of successful observation of ARGO float in the shallow water, using prolonged monitoring unmanned platform may contribute to predicting sound transmission loss if the temperature inversion and sound channel including background environment focusing are investigated in the center of the Yellow Sea.

• Journal of the korean academy of Pediatric Dentistry
• /
• v.49 no.3
• /
• pp.340-347
• /
• 2022

Distal displacement of the tooth germ of the mandibular second premolar (MnP2) leads to its impaction and obturation of the eruption path of the mandibular first molar delaying its eruption. The present case report describes the treatment of 2 cases of eruption guidance for distally displaced developing MnP2 that caused delayed eruption of the mandibular first molar. Intentional extraction of primary predecessor results in the mesial shift of the displaced MnP2. However, unfavorable distal ectopic eruption of the mandibular first premolar after the premature loss of primary second molar has been previously reported. Hemisection and sequential extraction of the mandibular primary second molar were performed to mesially shift the distally displaced MnP2, while preventing unfavorable distal ectopic eruption of the mandibular first premolar.

• Development and Reproduction
• /
• v.26 no.1
• /
• pp.23-36
• /
• 2022

Pharyngeal pouches, a series of outgrowths of the pharyngeal endoderm, are a key epithelial structure governing facial skeleton development in vertebrates. Pouch formation is achieved through collective cell migration and rearrangement of pouch-forming cells controlled by actin cytoskeleton dynamics. While essential transcription factors and signaling molecules have been identified in pouch formation, regulators of actin cytoskeleton dynamics have not been reported yet in any vertebrates. Cofilin1-like (Cfl1l) is a fish-specific member of the Actin-depolymerizing factor (ADF)/Cofilin family, a critical regulator of actin cytoskeleton dynamics in eukaryotic cells. Here, we report the expression and function of cfl1l in pouch development in zebrafish. We first showed that fish cfl1l might be an ortholog of vertebrate adf, based on phylogenetic analysis of vertebrate adf and cfl genes. During pouch formation, cfl1l was expressed sequentially in the developing pouches but not in the posterior cell mass in which future pouch-forming cells are present. However, pouches, as well as facial cartilages whose development is dependent upon pouch formation, were unaffected by loss-of-function mutations in cfl1l. Although it could not be completely ruled out a possibility of a genetic redundancy of Cfl1l with other Cfls, our results suggest that the cfl1l expression in the developing pouches might be dispensable for regulating actin cytoskeleton dynamics in pouch-forming cells.

• Journal of the Korean Recycled Construction Resources Institute
• /
• v.10 no.1
• /
• pp.15-22
• /
• 2022

In this study, the hydration reaction and strength characteristic of cement mortar with spent coffee ground(SCG) was investigated. As a result of the study, it was found that as the firing temperature of the SCG increased, the mass loss due to the combustion of organic matter increased, but the density increased. In addition, when the SCG were mixed, SCG interfered with the hydration reaction and the compressive strength was significantly lowered. On the other hand, the coffee grounds ash(SCG_Ash) calcined at 800 ℃ showed a hydration reaction and a compressive strength equivalent to or higher than that of OPC mortar.

• Proceedings of the SCSK Conference
• /
• 2003.09a
• /
• pp.162-177
• /
• 2003

It has been known that the color of skin reflects the blood flow within. In lips, the capillaries close to the skin surface are numerous; hence lips are redder than the rest of face. However, dermatological research on lips is not as advanced as research on facial or body skin, and little was known about the relationship between relatively dull-colored lips and skin blood flow. The physiological differences between colorful and dull-colored lips were studied by a two-dimensional laser Doppler blood flow analyzer, a spectrometer for the measurement of the degree of oxygen saturation, and a confocal microscope for observing inside lips non-invasively. Dull-colored lips and the corner of lips (dull-colored compared to the center) showed relatively poor blood flow and lower oxygenated hemoglobin. It was found that colorful lips (generally the young) had a blood flow that tended to run straight in parallel with the skin surface. This unique blood-capillary structure can express clear red blood. Those with dull-colored lips had lost this unique structure. Their blood ran perpendicularly from the deep of the skin and down back again into the deep part as like the blood circulation patterns of facial skin. Therefore, the lips of the latter group had fewer blood capillaries near skin surface in the lips than that of the colorful-lips group. A lipstick containing a-glucosyl-hesperidin, which is derived from certain citrus fruits and can enhance blood circulation, was applied for evaluating its effects. Blood flow was increased 30 min after the application. After two weeks of daily application, the lips' condition became noticeably less dull. These findings suggest that the decrease of blood flow in dull-colored lips is caused by the loss of the unique capillary structure and the use of the lipstick to increase blood flow can give a vivid color to lips.

• Journal of Advanced Navigation Technology
• /
• v.27 no.4
• /
• pp.374-381
• /
• 2023

This study focuses on the implementation of C-band radio navigation in the 5.03 ~ 5.15 GHz terrestrial band to cooperate with GNSS navigation mainly used in existing UAMs. This is one of the navigation technologies that can fully satisfy the requirements of Title 14 of CFR-135.165. According to the FAA, the use of two or more independent navigation sources for aircraft is proposed for aircraft. This study proceeded with the link budget derivation through radio wave propagation path loss analysis, and antenna shape design for miniaturized Doppler VOR, and DME design with enhanced positional distance resolution compared to conventional aircraft. The ground navigation system which is the result of this study, consists of a VOR/DME ground station and a terminal that can be mounted on UAM. Significant performance was confirmed through the production and testing of each prototype.

• Research in Plant Disease
• /
• v.28 no.4
• /
• pp.195-203
• /
• 2022

Zea mays, known as maize or corn, is a major staple crop and an important source of energy for humans and animals, thus ensuring global food security. Approximately 9.4% of the loss of total annual corn production is caused by pathogens including fungi, bacteria, and viruses, resulting in economic losses. Although the use of fungicides is one of the most common strategies to control corn diseases, the frequent use of fungicides causes various health problems in humans and animals. In order to overcome this problem, an eco-friendly control strategy has recently emerged as an alternative way. One such eco-friendly control strategy is the use of beneficial microorganisms in the control of plant pathogens. The beneficial microorganisms can control the plant pathogens in various ways, such as spatial competition with plant pathogens, inhibition of fungal or bacterial growth via the production of secondary metabolites or antibiotics, and direct attack to plant pathogens via enzyme activity. Here, we reviewed microorganisms as biocontrol agents against corn diseases.

• Elastomers and Composites
• /
• v.58 no.1
• /
• pp.32-43
• /
• 2023

The worldwide use of polyurethane foam products generates large amounts of waste, which in turn has detrimental effects on the surroundings. Hence, finding an economical and environmentally friendly way to dispose of or recycle foam waste is an utmost priority for researchers to overcome this problem. In that sense, the glycolysis of waste flexible polyurethane foam (WFPF) from automotive seat cushions using different industrial-grade glycols and potassium hydroxide as a catalyst to produce recovered polyol was investigated. The effect of different molecular weight polyols, catalyst concentration, and material ratio (PU foam: Glycols) on the reaction conversion and viscosity of the recovered polyols was determined. The obtained recovered polyols are obtained as single or split-phase reaction products. Besides, the foaming characteristics and physical properties such as cell morphology, thermal stability, and compressive stress-strain nature of the regenerated flexible foams based on the recovered polyols were discussed. It was observed that the regenerated flexible foams displayed good seating comfort properties as a function of hardness, sag factor, and hysteresis loss compared to the reference virgin foam. With the growing demand for a sustainable and circular economy, a global valorization of glycolysis products from polyurethane scraps can be realized by transforming them into profitable substances.