Novel Ni- and Fe-based alloys are developed to impart improved mechanical properties and corrosion resistance. The designed alloys are manufactured as a powder and deposited on a steel substrate using a high-velocity oxygen-fuel process. The coating layer demonstrates good corrosion resistance, and the thus-formed passive film is beneficial because of the Cr contained in the alloy system. Furthermore, during low-temperature heat treatment, factors that deteriorate the properties and which may arise during high-temperature heat treatment, are avoided. For the heattreated coating layers, the hardness increases by up to 32% and the corrosion resistance improves. The influence of the heat treatment is investigated through various methods and is considered to enhance the mechanical properties and corrosion resistance of the coating layer.

Aluminum alloys are extensively employed in several industries, such as automobile, aerospace, and architecture, owing to their high specific strength and electrical and thermal conductivities. However, to meet the rising industrial demands, aluminum alloys must be designed with both excellent mechanical and thermal properties. Computer-aided alloy design is emerging as a technique for developing novel alloys to overcome these trade-off properties. Thus, the development of a new experimental method for designing alloys with high-throughput confirmation is gaining focus. A new approach that rapidly manufactures aluminum alloys with different compositions is required in the alloy design process. This study proposes a combined approach to rapidly investigate the relationship between the microstructure and properties of aluminum alloys using a direct energy deposition system with a dual-nozzle metal 3D printing process. Two types of aluminum alloy powders (Al-4.99Si-1.05Cu-0.47Mg and Al-7Mg) are employed for the 3D printing-based combined method. Nine types of Al-Si-Cu-Mg alloys are manufactured using the combined method, and the relationship between their microstructures and properties is examined.

This study investigates the interfacial reaction between powder-metallurgy high-entropy alloys (HEAs) and cast aluminum. HEA pellets are produced by the spark plasma sintering of Al0.5CoCrCu0.5FeNi HEA powder. These sintered pellets are then placed in molten Al, and the phases formed at the interface between the HEA pellets and cast Al are analyzed. First, Kirkendall voids are observed due to the difference in the diffusion rates between the liquid Al and solid HEA phases. In addition, although Co, Fe, and Ni atoms, which have low mixing enthalpies with Al, diffuse toward Al, Cu atoms, which have a high mixing enthalpy with Al, tend to form Al–Cu intermetallic compounds. These results provide guidelines for designing Al matrix composites containing high-entropy phases.

Hepatic diseases are divided into two types: alcoholic and non-alcoholic. Non-alcoholic liver injury finally induces fatty liver and damages liver function. Many studies have demonstrated that Ecklonia stolonifera has antioxidative, antiinflammatory, and hepatoprotective activities. We conducted a 12-week double-blind, placebo-controlled, randomized trial to examine the efficacy of E. stolonifera extracts (ESE) on biochemical markers of hepatic function. Sixty-five subjects with mild or moderate liver injuries were randomly allocated to receive either 420 mg/d of ESE or a placebo for 12 weeks. Fifty-five participants completed the trial. No significant adverse events were observed among the subjects during the study. The primary end points were changes in plasma levels of aspartate transaminase (AST), alanine transaminase (ALT), and γ-glutamyltransferase (γ-GT). The secondary end points were changes in lipid profile levels, including total cholesterol (TC), triglyceride (TG), highdensity lipoprotein cholesterol (HDL), and low-density lipoprotein cholesterol (LDL). Compared with the baseline, AST and ALT levels decreased significantly in the ESE group compared to those in the placebo group (P<0.001). In addition, γ-GT levels in the ESE group were significantly lower than those in the placebo group (P=0.016). There were no differences in the TC, TG, HDL, and LDL levels between groups. In conclusion, ESE consumption for 12 weeks improved liver parameters in subjects with liver injury. Regular consumption of ESE could maintain liver health in individuals at risk of hepatic damage.

This study aimed to provide directions and implications for a future program by analyzing studies on diabetes programs from 2000 to 2020. Among the studies with control and experimental groups, the selected studies included ones that provided intervention to patients with diabetes and ones that contained descriptive statistics. Sixteen studies were selected to verify the effectiveness and homogeneity of the data coding meta-analysis. The overall effect size in the diabetes program combined estimate was 0.398 (95% CI: 0.268, 0.425, p=0.000). Among the dependent variables, fasting blood glucose (－0.616) and glycated hemoglobin (－0.442) showed median effect sizes, but the effect of fasting blood glucose was not statistically significant. In terms of the study design, non-randomized control trials (NRCTs) (－0.543) was more effective than randomized control trials (RCTs) (0.719). Among, the counseling and self-management program (－3.241) showed a very large effect size. Furthermore, the cognitive-behavioral (－0.828) and self-management (－0.482) programs were also found to have a positive effect on lowering fasting blood glucose. As the importance of diabetes management increases, further studies based on RCT should be actively performed, and differentiated and specialized diabetes intervention plans need to be established.

In this study, Telenomus remus Nixon (Hymenoptera: Scelionidae) was first reported as a natural enemy of the fall armyworm Spodoptera frugiperda (J.E. Smith) (Lepidoptera: Noctuidae) egg collected from corn fields in Korea, and its biological characteristics was studied. Based on morphological and molecular analysis, the parasitoid emerged from S. frugiperda eggs was identified as T. remus. We found that T. remus can attack the eggs of S. frugiperda, Spodoptera litra and Spodoptera exigua under a laboratory condition. The longevity of T. remus female adult was longer than that of male adult. The egg-to-adult period of T. remus was not affected by the host age and sex. T. remus female adult laid at least 1-3 eggs a day to a maximum of 37 or more eggs, and the most oviposited on the 3rd to 4th day after emergence. The host preference for oviposition of T. remus adult was high in the order of S. litura>S. exigua>S. frugiperda. T. remus preferred to parasitize 1- and 2-day-old host egg rather than 3-day-old host egg. When compared to the sex ratio of T. remus progeny, the rate of female progeny was higher at the initiation time of oviposition, while the proportion of male progeny increased significantly with female adult age, especially after 8-day-old adult. This information may be useful for improving T. remus mass rearing system and developing a biological control program to control S. frugiperda.

In this study, heavy metals (lead, cadmium, and mercury) and shellfish poisoning toxins (diarrhetic shellfish poisoning toxins, amnesic shellfish poisoning toxins) were investigated in a total of 104 shellfishes. According to the analysis of heavy metals, lead (Pb) was detected in the range of 0.0177-0.5709 mg/kg, cadmium (Cd) was detected in the range of 0.0226-1.4602 mg/kg, and mercury (Hg) was detected in the range of 0.0015-0.0327 mg/kg. Levels of Pb, Cd, and Hg were acceptable by Korean standards. Okadaic acid (OA) and dinophysistoxin-1 (DTX-1) were investigated for monitoring of diarrhetic shellfish poisoning toxins and OA and DTX-1 were not detected. As a result of monitoring of amnesic shellfish poisoning toxins, domoic acid was detected in 5 of 104 samples and detection ratio was 4.8%. The detection period was found as follows; 1 case in January, 1 case in February, 1 case in May, 2 cases in September. These showed that continuous monitoring for the management of shellfish poisoning toxins and heavy metals is required. In addition, this study can be used as reference data to strengthen managing heavy metals in fishery products.

This study was conducted to establish an appropriate period of use of sawdust spawn at low temperatures and a nutrient supplement medium for cultivation of Lentinula edodes ‘Hwadam’. Of the nutrient supplements, the total yield of rice bran (5%) + corn flour (5%) treatments were 673.3 g, which was higher than rice bran (551.6 g) and wheat bran (546.7 g) treatments, respectively. As shown by the growth of Lentinula edodes ‘hwadam' during to the sawdust spawn storage period (at 4oC), the period of spawn running, browning, fruiting body formation, and development was 27 d, 81 d, 5 d, and 11-13 d, respectively, regardless of the length of the storage period at 4 oC. After 3 months of storage of sawdust spawn, the number of fruiting bodies and yield decreased as the storage period increased. Therefore, the period of use of sawdust spawn (at 4 oC) for the stable production of fruiting bodies of Lentinula edodes ‘Hwadam’ was a maximum of 3 months.

This study was conducted to reduce the phenomenon of the biased cultivation of certain mushroom varieties and to develop a competitive variety of Grifola frondosa. We developed the first Korean white commercial mushroom strain, ‘Bakyeon’, by crossing monokaryons derived from brown strains. We have collected and tested the characteristics of mushrooms from domestic and international genetic resources since 2018. We bred the unique domestic variety, ‘Bakyeon’, which has the following characteristics. The optimal temperature for mycelial growth was 25~28oC and the optimal temperature for fruit body growth was 16~18oC. The new variety was similar to the control variety (Daebak) in terms of the pileus, which formed a pine cone shape, and the number of days of cultivation. The yield was 94.1 g/bottle, which was 23% lower than the 108.5 g/bottle yield of the control variety. When incubating the parent and control varieties, the replacement line was clear. Moreover, polymerase chain reaction analysis of mycelial DNA resulted in different band patterns between the parent and control varieties, confirming the hybrid species.

This study aimed to examine cucumber (Cucumis sativus) varieties adaptive to the desert climate by comparing and analyzing the growth, yield, and water consumption. Two long-sized cucumber varieties, ‘Gulfstream’ and ‘Imea’ and two medium-sized cucumbers, ‘Nagene’ and ‘Sausan’ were cultivated in coir substrate hydroponics under hot and humid greenhouse conditions from March 2 to June 20, 2020. On the 113 DAT, ‘Nagene’ had the longest plant height and the highest internode number. The marketable fruit number per plant was higher in the medium-sized varieties, which had more internode number. The marketable fruit number was 31.3 for ‘Gulfstream’, 30.7 for ‘Imea’, 57.8 for ‘Nagene’, or 56.0 for ‘Sausan’ with no significant difference in total fruit weights per plant. The water consumption required to produce 200 g of fruit was lower in the ‘Nagene’ (2.39 L) with the highest water use efficiency (WUE). Therefore, ‘Nagene’ variety may have higher adaptability to desert high temperature compared to the long-sized varieties, and it is going to be necessary to verify more medium-sized cucumber varieties.