Ulva compressa Linnaeus (UCL) is a green algae seaweed that performs photosynthesis and is used as a food material in some Asian regions including Korea. It is known to be the dominant species in copper ion-contaminated seas, and many studies on copper ion resistant mechanisms have been reported. UCL is known to have an excellent antioxidant effect, but limited information is available regarding its other physiological activities. In this study, we investigated the anticancer activity of 30% prethanol extracts of Ulva compressa Linnaeus (30% PeUCL) and the underlying mechanisms of its activity on human FaDu hypopharyngeal squamous carcinoma cells. The 30% PeUCL extracts suppressed FaDu cell viability without affecting normal cells (L929), as determined by MTT and viability assays. Furthermore, the 30% PeUCL extracts induced apoptosis, as determined by DAPI staining. The 30% PeUCL extracts inhibited colony formation effectively as well as wound-healing of FaDu cells, even at noncytotoxic concentrations. In addition, 30% PeUCL extracts induced apoptosis significantly through proteolytic cleavage of caspase-3, -7, and -9, and poly (ADP-ribose) polymerase, and by downregulation of Bcl-2 and upregulation of Bax in FaDu cells, as determined by Western blot analysis. Collectively, these results suggest that the inhibitory effect of 30% PeUCL extracts on the growth of oral cancer cells, colony formation and wound-healing may be mediated by caspase- and mitochondrial-dependent apoptotic pathways in human FaDu hypopharyngeal squamous carcinoma cells. Therefore, 30% PeUCL extracts can be administered as a natural chemotherapeutic drug for the treatment of human oral cancers.

고치벌과의 송충살이고치벌아과에 속하는 Aleiodes conina Quicke and Butcher, 2012를 국내 최초로 보고한다. 본 종에 대한 진단, 분포 및 삽화를 제공한다.

Various types of karst topographies are found worldwide. Owing to their global distribution, karst areas have been extensively studied by scientists who investigate new discoveries by linking the characteristics of karst topographies with their own research fields. However, there have been only a few studies on karsts in the Republic of Korea, and little research exists on their hydrogeology. Fragmentary studies have been conducted on the hydrochemical characteristics of groundwater in limestone areas, the causes of high arsenic concentrations in groundwater, and the hydraulic conductivity of limestone areas. Research on hydrogeological characterization and flow mechanisms in these areas has only began recently. Identification and the proper management of available groundwater resources in karst (limestone) areas is essential as their unique geological characteristics render it difficult to construct reservoirs or dams at appropriate scales. We have reviewed prior work on karsts in the Republic of Korea to provide information that supports water resource security in the karst areas, to improve the understanding of the equitable use of water resources, and to identify the best management practices for groundwater resource resilience improvement.

This study assessed the changes in the fiber properties of virgin and recovered fibers from lab-scale and pilot-scale depolymerization reactors based on the thermal air oxidation-resistance characteristics. Lab-scale and pilot-scale depolymerization reactors had different depolymerization volumes. Results showed that the lab-scale and pilot-scale peak solvent temperatures were 185 °C and 151 °C, respectively. The lab-scale had highest solvent temperature rate increase because of the small depolymerization volume and the dominant role of the cavitation volume. The structural properties of the recovered and virgin fibers were intact even after the depolymerization and after the pretreatment and oxidation-resistance test. We observed 1.213%, 1.027% and 0.842% weight loss for the recovered (lab-scale), the recovered (pilot-scale) and virgin fibers because of the removal of impurities from the surface and chemisorbed gases. Further, we observed 0.8% mass loss of the recovered fibers (lab-scale) after the oxidative-onset temperature because of the “cavitation erosion effect” from the dominant of the cavitation bubbles. The “cavitation erosion effect” was subdued because of the increased depolymerization volume in the pilot-scale reactor. Therefore, negligible impact of the pilot-scale mechanochemical recycling process on the structure and surface characteristics of the fibers and the possibility of reusing the recovered fibers recycling process were characteristic. Representative functional groups were affected by the thermal oxidation process. We conducted HPLC, HT-XRD, TGA– DSC, XPS, SEM, and AFM analysis and provided an extensive discussion of the test thereof. This study highlighted how misleading and insufficient small-lab-scale results could be in developing viable CFRP depolymerization process.

The effect of oxidation time on the characteristics and mechanical properties of spent nuclear fuel cladding was investigated using Raman spectroscopy, tube rupture test, and tensile test. As oxidation time increased, the Raman peak associated with the tetragonal zirconium oxide phase diminished and merged with the Raman peak associated with the monoclinic zirconium oxide phase near 333 cm−1. Additionally, the other tetragonal zirconium oxide phase peak at 380 cm−1 decreased after 100 d of oxidation, whereas the zirconium monoclinic oxide peak became the dominant peak. The oxidation time had no effect on the tube rupture pressure of the oxidized zirconium alloy tube. However, the yield and tensile stresses of the oxidized nuclear fuel cladding tube decreased after 100 d of oxidation. The results of the scanning electron microscopy and transmission electron microscopy were represented with the in-situ Raman analysis result for the oxide characteristics generated on the cladding of spent nuclear fuel.

Imperforate hymen is a rare congenital disorder that may predispose to retention of fluid in the vagina and uterus, thereby resulting in conditions such as hematocolpos, pyocolpos, and pyocolpometra in female dogs. A 7-year-old intact female shih tzu exhibiting abdominal distension, depression, anorexia, dysuria, dyschezia, and tenesmus was diagnosed with pyocolpos; a 9-year-old intact female Yorkshire terrier with abdominal mass, dysuria, and tenesmus was diagnosed with hematocolpos; and a 7-year-old intact female shih tzu with dysuria, dyschezia, anorexia, and vomiting was diagnosed with pyocolpometra. Ovariohysterectomy and partial vaginectomy were performed, and the blind end of the vaginal stump was omentalized. This clinical report provide diagnostic process and surgical treatment option for congenital vaginal obstruction cases.

Heterogeneous nuclear ribonucleoprotein A2/B1 (hnRNPA2/B1) is an N6-methyladenosine (m6A) RNA modification regulator and a key determinant of premRNA processing, mRNA metabolism and transportation in cells. Currently, m6A reader proteins such as hnRNPA2/B1 and YTHDF2 has functional roles in mice embryo. However, the role of hnRNPA2/B1 in porcine embryogenic development are unclear. Here, we investigated the developmental competence and mRNA expression levels in porcine parthenogenetic embryos after hnRNPA2/B1 knock-down. HhnRNPA2/B1 was localized in the nucleus during subsequent embryonic development since zygote stage. After hnRNPA2/B1 knock-down using double stranded RNA injection, blastocyst formation rate decreased than that in the control group. Moreover, hnRNPA2/B1 knock-down embryos show developmental delay after compaction. In blastocyste stage, total cell number was decreased. Interestingly, gene expression patterns revealed that transcription of Pou5f1, Sox2, TRFP2C, Cdx2 and PARD6B decreased without changing the junction protein, ZO1, OCLN, and CDH1. Thus, hnRNPA2/B1 is necessary for porcine early embryo development by regulating gene expression through epigenetic RNA modification.

The purpose of this study is to analyze interactions between learners and the instructor (ILI) and interactions among the learners (IAL) themselves in a single university reading class with a focus on scaffolding. Thirty-three learners majoring in computer engineering and public administration participated in the class. Twenty-six out of 33 learners took a non-face-to-face online class (NFTFOC) for a 15-week semester, and the remaining seven learners chose to take a face-to-face class (FTFC) for the five weeks after the mid-term exam. Data from both the NFTFOC and FTFC were collected for 15 weeks from September to December 2021 including an automatic video recording system, quizzes, assignments, etc. through chatting boxes, bulletin boards, and emails. The obtained data were analyzed into both qualitative descriptions and quantitative statistical measures. The results showed that interactions in the low and mid-level of higher-order thinking from both the linguistic and cognitive perspectives occurred similarly, and both amplifying and simplifying of scaffolding functions in NFTFOC were more frequently observed than those in FTFC. In addition, both NFTFOC and FTFC got better scores on the post-test. As development occurs in language learning, a longitudinal and in-depth analysis of the language learning processes is required in future studies.

Purpose: Since the COVID-19 pandemic, virtual simulation practice has been increasingly activated as an alternative to clinical practice in nursing colleges. This study aimed to provide basic data by confirming changes in self-efficacy and nursing knowledge in the virtual simulations of nursing students, and identifying virtual presence, virtual patient learning system evaluation (VPLSE), and practical satisfaction. Methods: This was a single-group pre-post quasi-experimental study. The subjects were 28 third-grade nursing students. Results: Self-efficacy and nursing knowledge increased significantly (p<.001). Virtual presence had a significant positive correlation with VPLSE) (p=.002) and practice satisfaction (p=.011). There was also a significant positive correlation between virtual simulation learning evaluation and practice satisfaction (p<.001). Conclusion: Based on these results, virtual simulation practice can be used with clinical practice as an educational method to improve nursing students' self-efficacy and nursing knowledge in nursing education. Virtual presence was confirmed as a significant variable to improve practice satisfaction and VPLSE. It is necessary to develop a virtual simulation program that can improve virtual presence through collaboration with virtual reality technology experts.

We investigated the effect of habitat environment and colony characteristics on floral bud development in Rhododendron brachycarpum native to Ulleung Island of Korea. Two habitats were considered. Habitat B had a remarkably higher altitude and steeper slope than habitat A. Therefore, fewer types of trees existed on the upper layers, and the density was low. Hence, the degree of light transmission within the community was higher in habitat B. Additionally, flowering ratio of shoots was higher in habitat B, and the amount of light was also relatively higher. The lower the amount of light, lesser the floral development, the higher the leaf area and the specific leaf area, lower the dry weight and chlorophyll content. The total carbohydrate (T-C) and nitrogen (T-N) in shoots are more important than the relative T-C and T-N ratios per leaf. Finally, this study revealed that the floral bud development and flowering of native rhododendrons are strongly associated with the degree of assimilate accumulation in shoots, and that sufficient assimilate accumulation in shoots is essential for stable flowering.

Vitamin K1 (VK1) has been widely used as a coumarin antagonist and for the treatment of hemorrhagic disease in veterinary practice. However, the potential mechanism of adverse reaction after VK1 injection has been not fully elucidated. In this study, two cases of anaphylactic reactions after subcutaneous VK1 injection were presented, and then an experimental study was performed to further characterize the anaphylactic reactions. Two dogs developed anaphylactic reactions after subcutaneous VK1 injections and were promptly treated with antihistamines and glucocorticoids, after which abnormal signs related to anaphylaxis disappeared. Subsequently, a study was undertaken to ascertain the nature of the adverse reactions to subcutaneous VK1 injection. Six healthy laboratory beagle dogs received subcutaneous VK1 administrations once daily for eight days. They were monitored for clinical signs after each injection, and blood samples were collected for the measurement of plasma histamine and immunoglobulin E concentrations using enzyme-linked immunosorbent assay. All six dogs showed mild angioedema after the VK1 injections. The dogs also displayed clinical signs including sneezing, coughing, skin reddening, excess salivation, pawing the ground, and somnolence on days 4, 6, and 8. Plasma histamine and immunoglobulin E concentrations were significantly increased by the repeated injections. In summary, this study describes anaphylactic reactions resulting from subcutaneous VK1 administration in dogs. Clinicians should be aware that the repeated subcutaneous injection of VK1 can trigger an anaphylactic reaction in dogs.

This paper explores a college EFL course designed to practice reading for pleasure during the pandemic. Sixty EFL college learners in a required English course read Mark Haddon’s (2004) [The Curious Incident of the Dog in the Night-time] within the structure of a regular reading and writing focused academic English course. Reading for pleasure is often considered unfit for inclusion in regular curriculum. Nevertheless, for digital natives, the act of pleasurable reading especially in L2, should be actively implemented into classroom activities. This study follows a case study which practices reading for pleasure by utilizing weekly quizzes, discussion questions and response paper. Students’ feedback was collected and analyzed in order to share students’ experiences in completing the tasks. The feedback shows how weekly quizzes and class discussions have encouraged them to continue reading the text, influenced their attitude on reading English books and how they were able to empathize with the characters. This paper invokes the need to include reading young adult literature into general English courses for college learners to make them lifelong readers of L2.

고치벌과의 송충살이고치벌아과에 속하는 Aleiodes thirakupti (Butcher et al., 2012)을 국내 최초로 보고한다. 본 종에 대한 진단, 분포 및 삽 화를 제공한다.

Designing and producing a low-cost, high-current-density electrode with good electrocatalytic activity for the oxygen evolution reaction (OER) is still a major challenge for the industrial hydrogen energy economy. In this study, nanostructured Fe-doped CuCo(OH)2 was discovered to be a precedent electrocatalyst for OER with low overpotential, low Tafel slope, good durability, and high electrochemically active surface sites at reduced mass loadings. Fe-doped CuCo(OH)2 nanosheets are made using a hydrothermal synthesis process. These nanosheets are clumped together to form a highly open hierarchical structure. When used as an electrocatalyst, the Fe-doped CuCo(OH)2 nanosheets required an overpotential of 260 mV to reach a current density of 50 mA cm−2. Also, it showed a small Tafel slope of 72.9 mV dec−1, and superior stability while catalyzing the generation of O2 continuously for 20 hours. The Fe-doped CuCo(OH)2 was found to have a large number of active sites which provide hierarchical and stable transfer routes for both electrolyte ions and electrons, resulting in exceptional OER performance.

Korea Institute of Radiological and Medical Sciences provides proton irradiation service of up to 40 MeV using cyclotron. The use of such a cyclotron was approved in advance to satisfy the Nuclear Safety Act, and radiation safety was evaluated in this process. The Monte Carlo method is generally used to evaluate the shielding safety of high-energy accelerators, and MCNP 6.2 was used in the previous evaluation. In this study, in order to verify the results of previous evaluation, the calculation results of MCNP 6.2 and Particle and Heavy Ion Transport code System (PHITS) 3.24 are compared. PHITS is a general-purpose Monte Carlo particle transport simulation code that is used in many studies in the fields of accelerator technology, radiotherapy, space radiation, etc. In the previous evaluation, the effective dose by neutrons and photons generated by the collision of 40 MeV 20 μA of protons with a 10.5 mm thick beryllium target was evaluated, and in this study, this was reproduced with PHITS. As the radiation exposure evaluation for the user or pubic is evaluated based on the radiation dose and energy distribution generated around the target, the effective dose and energy distribution received by the water phantom with a radius of 1 cm on the front, side, and back of the target were calculated. T-Track, a tally of PHITS, was used to calculate effective dose, which is similar to F4 tally of MCNP 6.2 using a dose conversion factor. For the dose conversion factor, the value suggested as AP irradiation in Publication 103 was used. As a result of the calculation, the effective dose by neutrons at the front, side and back of the target was 1.42×105, 2.09×104, and 1.39×104 mSv·h−1, respectively, which was similar to 2.00×105, 1.84×104, and 2.59×104 calculated using F4 tally in MCNP. Moreover, the results of calculating the effective dose by photons using PHITS were 4.81×10, 3.10×10, and 2.66×10, respectively, and the results of calculating MCNP were 4.49×102, 6.45×10, and 9.64×10. The average energies of neutrons were 11.2, 0.69, and 0.31 MeV when calculated by PHITS, respectively, and 13.8, 7.8, and 4.6 when calculated by MCNP. Moreover, the average energies of photons were 1.98, 0.98, and 0.86 when calculated by PHITS, respectively, and 3.9, 3.2, and 2.6 when calculated by MCNP.

The permanent shutdown of NPPs (nuclear power plants) has been growing steadily around the world. Also, permanent shutdown of old NPPs has been determined following to Kori-1 and Wolsong-1 in the Korea. Among issues of decommissioning of NPPs, especially, the management of radioactive waste is the most sensitive issue. According to IAEA, a large volume of radioactive concrete waste would be generated from decommissioning of nuclear facilities. Also, EC (European commission) expected that about 500 million tons of concrete will be produced in Europe by 2060 due to decommissioning of NPPs. It is known that the radioactive concrete consists of surface contaminated concrete and activated concrete. So, if contaminants from radioactive concretes can be removed using specific technologies, volume reduction of concrete can be achieved. Since there is no experience of decommissioning of NPPs in Korea, it is important to analyze previous cases. In this study, decontamination of radioactive concrete is analyzed through previous studies. Decontamination technologies of concrete are composed of mechanical methods, chemical methods, and thermal methods. Mechanical methods are physical technologies separating contaminants from concrete using scabbling, milling, and vacuum cleaning. In chemical methods, contaminants were removed from concrete using an oxidizing agent/reducing agent, acid/base. Thermal methods are removal technologies using lasers, microwaves, and pulsed power discharge. Some methods still have practical use cases, and further research is needed on the issue of generation of secondary waste. Review on the experience of decontamination of concrete show that waste of concrete generated during decommissioning of NPPs are expected to have effect of large volume reduction. However, many studies are needed because secondary waste and decontamination cost is sensitive issue of concrete generated during decommissioning of NPPs. In order to successful decommissioning of NPPs in Korea, various research of decontamination of concrete are need

The establishment of processes for the decommissioning a Nuclear Power Plant (NPP) is one of the objects that must be prepared in carrying out the decommissioning project. In particular, in the domestic situation, where there is no experience of decommissioning commercial NPPs, it is necessary to organize the tasks and contents well in advance for the successful initiation of the project. Therefore, this study intends to present a guide-level approach to develop management for domestic decommissioning projects. As a documented template for recognizing a process, there may be a process map and description, and information such as the work structure and the relations between the activities should be indicated. In reality, activities will be managed through a set of computer system, so it would be better if the work content, activity flow, relation, management target information, computerization contents, etc. were materialized in the process. What is important here is to define the management areas and activities and draw the activity flow. Domestically, it has rich experience in construction of NPPs and has a track record of exporting NPPs to the UAE. From these experiences, we have established a framework for standardized work in construction management and construction processes, and are performing them through a computerized system. Since the work of decommissioning has a similar nature to that of construction, we will be able to benchmark the procedure for the decommissioning from the construction management procedures. Typically, in the case of schedule management, the concept and structure of the construction process will be applicable to the decommissioning. Meanwhile, the licensee of domestic decommissioning is the same as the licensee that performs the operation, and the members who will perform the decommissioning also have experience working in the operation period. Therefore, the decommissioning works are an extension of the task during operation. Representatively, there are some processes that can be applied as it is even when decommissioning, such as dismantling work and the safety management process of the radiation zone. Therefore, in carrying out the decommissioning of NPPs in Korea, processes and activities of the management area should be established from the construction processes with abundant experience and the processes during operation. Rather than making a completely new work process, this approach that properly reflects the existing work flow is expected to be an appropriate way to avoid the repulsion of employees and maladjustment to the new environment.

The structural stability of the recycled concrete disposal container was evaluated and compared the applicability of the current design standards for recycled concrete of nuclear power plant. The structural stability requirement for concrete disposal containers is 37.7 MPa or more. As a result of the compressive strength test on recycled concrete, 50% of coarse aggregates of recycled concrete was 42.1 MPa. In addition, it was found that the bending strength and shear strength of recycled reinforced concrete beam exceeded the current design standard. Therefore, it is judged that recycled concrete containing coarse aggregates can be sufficiently utilized. It was possible to ensure the structural stability of the concrete container without changing the design specifications and reinforcing bars when recycled concrete is applied.

Currently, in domestic nuclear power plants (NPP), the spent filters (SFs) used for the purpose of reducing and purifying the radiation of the primary cooling water system are temporarily stored in an untreated state. In order to dispose of SFs, radioactive nuclide analysis (RNA) of SFs is required to be conducted. As segmented gamma scanner (SGS) is already being used in Kori NPP, utilizing SGS for RNA of SFs would be practical and economical. In this paper, factors required to be considered to improve accuracy of SGSs for RNA of SFs are studied. The analysis of the nuclide inventory of the packaging drum for radioactive waste should be performed by the indirect drum nuclide analysis method. The material of the SFs is iron (SS304) on the outside, and paper on the inside. In addition, to meet disposal acceptance criteria, radioactive waste drums are packaged in thick grouting or shielding drums. Therefore, it is necessary to derive an appropriate correction method for high inhomogeneity and thick media. Considering these factors, evaluating radionuclides inventory plans to measure gamma rays in SGS mode. Correct the gamma ray measurement by examining the medium attenuation factor and error factors. In this way, the inventory of gamma nuclides is calculated, and the specific radioactivity of beta ray and alpha particle emitting nuclides other than gamma rays is planned to be calculated by applying scaling factors.

As the number of aging nuclear power plants increases, the market for dismantling nuclear power plants is growing rapidly. About 40% of the cost of dismantling nuclear power plants is the waste treatment cost incurred during the dismantling process, of which concrete waste accounts for a significant portion of the total waste. Securing technology for reducing and recycling concrete waste is very important not only in terms of economy but also in terms of environment. The objective is to synthesize geopolymer using inorganic materials from cement fine powder in concrete waste. Cement fine powder in concrete waste has a large amount of inorganic elements necessary for filing materials for radioactive waste treatment such as CaO and SiO2. In particular, Ca(OH)2 is synthesized by extracting Ca2+ from concrete waste. It can be used as an alkali activator to synthesize geopolymer. The mortar from crushed concrete was used as a source of calcium. The first step is to react with concrete waste and hydrochloric acid to extract ions. The second step is to react with NaOH and synthesize Ca(OH)2. The product was divided into two stages according to the reaction method and order. The first and second products were washed and dried, and then XRD and XRF were performed. The second product was matched only Ca(OH)2 and CaCO3 at the XRD peak. In the case of XRF, it was analyzed to have a purity of 67.80–78.73%. Synthesis of geopolymer by recycling materials extracted from concrete waste can reduce disposal costs and improve the utilization rate of disposal sites.