배추는 한국에서 연중 소비되는 김치의 주 원료이며, 노지에서 주로 재배되고 있다. 온실 재배 수경재배 시 스템은 기후 변화에 영향을 받지 않고 토양을 대신한 배지를 사용함으로써 토양 병원균으로부터 작물을 보호할 수 있어 재배 안정성을 확보할 수 있다. 수경재배용 배지 중 일부는 재사용이 가능하고, 이러한 배지의 조성은 작물 생 장과 품질에 영향을 줄 수 있다. 본 연구는 재사용 코이어 배지 또는 인공배지를 첨가한 배지 조성에 칼슘 공급원을 처리하여 배추(Brassica rapa ‘Bulam Plus’)를 수경재배 했을 때 배액과 생육에 미치는 영향을 알아보고자 10주동 안 수행하였다. 배지 조성은 재사용 코이어: 피트모스: 펄라이트 비율(v/v/v)을 각각10:0:0, 7:2:1, 5:3:2의 세 처리 와 각 처리에 칼슘 공급원인 CaSO4(G)와 CaO(Q)를 200g/m2 혼합한 총6가지 처리(G10:0:0, G7:2:1, G5:3:2, Q10:0:0, Q7:2:1, Q5:3:2)하였다. 배액량, 배액의 pH와 EC, 생육, 잎끝마름(Tipburn)발생을 조사하였다. 배추 생육이 증가함에 따라 모든 처리에서 배액률은 감소하였고, 처리 9주째는 20% 미만으로 감소하였다. 배액의 EC는 G 처리가 Q 처리 보다 높았으나 배액의 pH는 Q 처리가 높았다. 처리 10주째 배추의 초장, 엽수, 엽폭은 처리 간 유의성이 없었다. 엽 록소함량값(SPAD)은 G7:2:1과 G5:3:2처리에서 높게 나타났다. 잎의 당도와 건물중은 Q5:3:2처리에서 높았으며, 건물 중이 관찰되었다. 배추의 잎끝마름 발생은 처리 25일째 관찰되었으며, G7:2:1처리에서 가장 높았다. 이상의 결과를 종합할 때 CaO가 첨가되고 재사용 코이어 50% 함유된 Q5:3:2처리에서 수경 재배된 배추 생육이 양호하였다. 본 연 구는 간이 시설을 적용된 수경재배 시스템에서의 안정적 배추 재배를 위해 재사용 코이어 배지와 칼슘 공급원에 관 한 기본 정보를 제공하고자 하였다.

This study investigated whether calcium (Ca) addition improved the recovery of neodymium (Nd) and dysprosium (Dy) from Nd-Fe-B magnet scrap using magnesium (Mg)-based liquid metal extraction (LME). Traditional LME processes are limited to temperatures up to 850 °C due to oxidation issues, reducing the efficiency of rare earth element (REE) recovery, especially for Dy. By adding 10 wt.% Ca to Mg and increasing the processing temperature to 1,000 °C, we achieved nearly 100% Nd and approximately 38% Dy recovery, compared to 91% and 28%, respectively, with pure Mg at 850 °C. However, excessive Ca addition (20 wt.%) decreased the recovery efficiency due to the formation of stable intermetallic compounds. These results highlight the critical role of Ca in optimizing REE recycling from Nd-Fe-B magnet scrap.

Hyperoxaluria is a disorder associated with an increased risk of renal stones, one of the most common conditions. For people with hyperoxaluria, there are a limited number of effective therapeutic options. The aim of this study was to examine whether an oxalate-degrading enzyme, oxalate decarboxylase (OxdC), can inhibit crystallization of calcium oxalate (CaOx) in vitro, and whether it can prevent nephrolithiasis caused by CaOx induced by ethylene glycol (EG) in rats. When OxdC was applied at various concentrations to CaOx in vitro, there was a significant reduction in the crystallization of CaOx. The OxdC was found to inhibit crystal formation as well as the formation of crystals that had sharp edges. In animal experiments, rats that had been treated with EG showed impaired renal filtration functions, as well as increased deposition of CaOx crystals and the creation of kidney stones. It has been found that oral administration of OxdC to rats with chronic EG-induced nephrolithiasis that is characterized by CaOx intratubular crystal deposits with hyperoxaluria dramatically reduces the severity of the disease. The results of this study point to a potential therapeutic approach for treating human hyperoxaluria as well as CaOx nephrolithiasis that could be achieved by the oral administration of OxdC.

In this study, the expression of genes related to fruit ripening was investigated using realtime PCR. The study aimed to determine the effective conditions of calcium compounds (Calcium citrate, calcium chloride, calcium nitrate, GH-Ca, OS-Ca) and chitosan treatment to extend the shelf-life in the ‘Kumhong’ nectarine and ‘Madoka’ peach fruits. In this study, in the ‘Kumhong’ and ‘Madoka’ fruits, the expression of genes related to cell wall degradation, pectin lyase (PL), polygalacturonase (PG), and pectin methylesterase (PME), was inhibited by calcium, chitosan, or a mixture (Chitosan+CaCl2) treatment. In ‘Madoka’ peach, although the expression of the PG gene was suppressed at pre-harvest Ca and chitosan treatment, the expression of the PL gene was induced at pre- and post-harvest Ca and chitosan treatment compared to the control. The spray of calcium, chitosan itself, or a mixture (Chitosan+ CaCl2) on the trees at the ripening stage and harvested fruits can extend the shelf-life by suppressing the expression of cell wall degrading enzymes genes (PL, PG, PME) in ‘Kumhong’ nectarine and ‘Madoka’ peach tree. These results provide valuable information for the development of technology for the extension of the shelf-life of peach and nectarine fruits.

본 연구는 생육시기별 한지형 잔디인 왕포아풀에 생장조정 제 trinexapac-ethyl(TE)과 prohexadione-calcium(PC) 을 처리 시 잔디의 품질 변화와 생장 억제 효과를 조사하였다. 처리구는 대조구와 생장조정제 처리구인 TE 처리구와 PC처리 구로 설정하였다. 1차 시험(여름철, 8월)과 2차 시험(가을철, 10월) 조사에서 대조구와 비교하였을 때, 왕포아풀의 가시적 품질 및 엽록소 함량은 통계적으로 유의적인 차이는 없었고, 약해는 발생하지 않았다. TE와 PC처리 후 28일 경과 시 잔디 초장은 1차 시험에서 대조구보다 각각 34.9%와 32.2% 정도, 2차 시험에서는 35.5%와 33.8% 정도 감소하였다. 대조구와 비교 시 TE와 PC처리구의 잔디 예지물은 1차 시험에서 각각 47.2%와 45.0%씩, 2차 시험에서 35.6%와 31.0%씩 감소되 었다. 생육시기별 비교에서 TE는 약제처리 후 28일 경과 시, PC는 7일 경과 시 각각 1차 시험에서 생장 억제 효과를 나타 냈다. 상기 결과들의 종합한 결과는 TE와 PC 처리 시 왕포아 풀에서 약해가 발생하지 않았고, 잔디의 경엽신장과 예지물을 감소시키는 것을 확인하였다. 또한, 생장조정제는 잔디 관리 에서 여름철과 가을철 모두 이용할 수 있으나 여름철에 생육 억제 효과가 높게 나타났다.

Volcanic seawater has been naturally filtered and purified by volcanic rock layers. It contains abundant minerals such as calcium, magnesium, and iron. This study investigated the genotoxicity of calcium from Jeju lava seawater (CJLS). We performed bacterial reverse mutation assay, chromosomal aberration assay, and mammalian micronucleus test at up to 5,000 g/plate concentrations with or without metabolic activation to determine the CJLS genetic toxicity. None of these tests showed any mutagenic potential. The bacterial reverse mutation assay showed that the CJLS did not induce mutagenicity in Salmonella typhimurium TA98, TA100, TA1535, TA1537, and Escherichia coli WP2uvrA with or without metabolic activation of the S9 mixture. The oral administration of CJLS also did not significantly increase the number of micronucleated polychromatic erythrocytes or the mean ratio of polychromatic to total erythrocytes. Additionally, CJLS did not cause a significant chromosomal aberration in CHL cells in the presence or absence of S9 activation. Therefore, CJLS could be considered as a reliable and safe functional food ingredient.

This study aimed to predict the shelf life of black soybean Sunsik to develop a functional labeling system for the product. The Arrhenius equation was used to calculate the shelf life by examining alterations in the dietary fiber and calcium levels of black soybean Sunsik stored at 25, 35, and 50°C for 0, 6, and 12 months. Dietary fiber and calcium analyses were performed according to the experimental methods specified in the Food Code of the Ministry of Food and Drug Safety. Both black soybean Sunsik (BS) and black soybean Sunsik containing nondigestible maltodextrin and calcium lactate (BSN) exhibited an upward trend in dietary fiber content after 12 months of storage, compared to their initial levels. During storage, the phytate in Sunsik degraded, releasing cations that facilitated the formation of new cross-links between pectic acid and middle lamella, which ultimately increased dietary fiber content. Conversely, the calcium contents of both BS and BSN decreased with prolonged storage. Based on these findings, the expected shelf life of BS and BSN was calculated as 15.65 and 28.34 months, respectively.

Bentonite is a promising buffer material for high-level radioactive waste (HLW) disposal due to the high nuclides sorption capacity and swelling property. However, bentonite has the potential to generate colloid particles, with small particle sizes less than 1,000 nm when in contact with groundwater. The bentonite colloids easily form pseudo-colloid with the released nuclides and migrate through the water-conducting rock to the biosphere. Therefore, understanding the generation and migration of bentonite colloids is crucial in assessing the safety of the HLW repository. In this study, an artificial fracture system was prepared to investigate colloid release from compacted bentonite. A 250 mm diameter acrylic artificial fracture system was used, with 30 mm of compacted calcium bentonite installed. Artificial groundwater flow was injected into the system at a flow rate of 250 μL/h, and every 6 mL of leachate was collected by a fraction collector. A film-type pressure sensor was equipped to monitor the swelling pressure, and the swelling was observed using a digital microscope. The results indicate that the compacted bentonite formed a mineral ring originating from the swelling of the bentonite, and the end of the ring generated colloid particles due to chemical erosion. Although the release rate of colloids increased with increasing flow rate, the colloid ratio depended on the low ionic strength of the injected artificial groundwater. This work contributes to the understanding of the chemical erosion and colloid release mechanism of compacted bentonite.

The objective of this study is to assess the impact of spray drying conditions on medium-chain triglyceride (MCT) loading, solubility, and release of an MCT-loaded solid self-emulsifying system in a water-insoluble oily substance. MCT-loaded solid self-emulsifying systems are prepared by spray drying with SDS and calcium silicate. The effects of inlet temperature (60, 80, or 100oC) and feed solution composition (0, 10, 50, 90, or 100% ethanol) on physicochemical properties of MCT-loaded solid self-emulsifying systems are studied. The inlet temperature significantly affects the water solubility of MCT. Moreover, the feed solution composition significantly affects water solubility, release rate, and MCT loading. The MCT-loaded solid self-emulsifying system obtained at 60oC using 90% ethanol feed solution shows the best physicochemical properties among the synthesized products and exhibits better water solubility (4.43 ± 0.44 vs. 0 μg/mL) and release (94.4 ± 1.6 vs. 32.8 ± 7.4%, 60 min) than a commercial product. Furthermore, the MCT-loaded solid self-emulsifying system shows an excellent emulsion droplet size (approximately 230 nm).

본 연구는 ‘암기조생’ 감귤 과실의 표면온도와 일사량 간의 상관관계를 분석하여 일소가 유발되는 과실 표면온도를 예측 하고 일소 발생을 경감시키고자 수행하였다. 이를 위해 기온 이 31℃일 때 30분 간격으로 5분 미세살수와 1% 탄산칼슘, 4% 카올린 용액을 10일 간격으로 3회 엽면살포하여 일소과 발생과 과실 품질을 조사하였다. 과실 표면온도는 일사량과 R = 0.788(p < 0.01)로 유의한 정의 상관관계를 나타냈으며 한 낮에는 기온보다 최고 16℃가 높았다. 과실 표면온도를 추정 하는 회귀식 y = 0.099 × (대기온도) + 0.018 × (일사량) + 20.779(R = 0.687, p < 0.01)을 도출하였다. 30분 간격으로 5 분 미세살수시 수관 내부 온도가 무처리보다 5.1℃ 낮았다. 일 소과 발생률은 미세살수구가 2.1%로 무처리구보다 2배 이상 낮았고 통계적으로 유의성을 나타냈으나, 과실 품질은 처리 간에 비슷하였다. 햇빛을 반사하거나 미세살수를 실시하여 과실 표면온도를 낮추면 일소 발생을 줄일 수 있을 것으로 보 인다.

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.

Unhealthy dietary behavior such as insufficient calcium intake can be one of risk factors of osteoporosis and chronic diseases in older people. This study evaluated the recent trends in dietary calcium intake and the food source in Korean adults aged 50 years or older using the Korea National Health and Nutrition Examination Survey (KNHANES, 2015-2019) data. This study used 24-hour recall survey data to investigate the calcium intake, the major food groups and main dishes contributing to the calcium intake. The mean calcium intake was 479.55-506.81 mg/day. The major food groups that contribute to calcium intake were vegetables, milks and fishes. Dairy and frozen desserts and kimchi were the major dish groups that contributed to the calcium intake. Calcium intake from milk in dairy and frozen dessert group has been high in last 5 years (50-64 years old: 34.71-47.68 mg, 65-74 years old: 29.72-43.65 mg, over 75 years old: 22.91-42.93 mg). In addition, baechu-kimchi is the most contributed to the calcium intake in kimchi group (50-64 years old: 35.10-41.47 mg, 65-74 years old: 29.62-34.96 mg, over 75 years old: 23.79-29.13 mg). In conclusion, various source of calcium needs to be recommended to increase intake calcium in over 50 years, which may reduce chronic diseases and improve quality of life.

본 연구는 헤이워드 다래나무의 비정상 생장 관련 문제점을 파악하고자, 건전 개체와 비건전 개체 간의 물리·해부학적 특성 및 Calcium Oxalate 형성 특성을 비교분석 하였다. 두 집단 간 밀도와 함수율 등의 물리적 요인과 연륜폭, 도관직경, 도관비율, 방사조직 높이와 너비 등의 해부학적 특성 요인을 비교분석해 본 결과 모든 요인에서 유의적인 차이가 나타났다. 특히 Calcium oxalate 결정은 주로 수피 부분에 여러 개가 다발형태로 다수가 존재하였으나, 도관 주위에서는 출현율이 낮았고, Pith와 목질부에서는 거의 나타나지 않았다. 이러한 Calcium oxalate 결정체는 건전개체(9.0 ×106/g개) 보다 고사가 진행 중인 비건전개체(10.4×106/g)에서 유의적으로 출현빈도가 높게 나타났음을 알 수 있었다.

Near infrared reflectance spectroscopy (NIRS) is routinely used for the determination of nutrient components of forages. However, little is known about the impact of sample preparation and wavelength on the accuracy of the calibration to predict minerals. This study was conducted to assess the effect of sample preparation and wavelength of near infrared spectrum for the improvement of calibration and prediction accuracy of Calcium (Ca) and Phosphorus (P) in imported hay using NIRS. The samples were scanned in reflectance in a monochromator instrument (680–2,500 nm). Calibration models (n = 126) were developed using partial least squares regression (PLS) based on cross-validation. The optimum calibrations were selected based on the highest coefficients of determination in cross validation (R2) and the lowest standard error of cross-validation (SECV). The highest R2 and the lowest SECV were obtained using oven-dry grinded sample preparation and 1,100-2,500 nm wavelength. The calibration (R2) and SECV were 0.99 (SECV: 468.6) for Ca and 0.91 (SECV: 224.7) for P in mg/kg DM on a dry weight, respectively. Results of this experiment showed the possibility of NIRS method to predict mineral (Ca and P) concentration of imported hay in Korea for routine analysis method to evaluate the feed value.