Background: Logistics service workers (LSWs) face significant occupational challenges, with ankle sprains being the second most prevalent work-related musculoskeletal disorder. Foot posture, assessed through the navicular drop test, can significantly influence dynamic balance performance, which is crucial for injury prevention in physically demanding occupational settings. Objects: This study aimed to investigate differences in dynamic balance performance among LSWs with pronated, supinated, and normal foot types using the Y-Balance test (YBT), comparing reach distances across anterior, posteromedial, and posterolateral directions. Methods: A total of 205 LSWs were classified into three groups based on navicular drop measurements: supinated (n = 44), normal (n = 94), and pronated (n = 67) foot types. The YBT was performed on the dominant leg, measuring reach distances in three directions. Participants’ demographic characteristics were recorded, and statistical analyses were conducted using one-way analysis of variance (ANOVA) with Bonferroni correction. Results: Significant differences in YBT performance were observed across all three directions (anterior: p = 0.009, posterolateral: p = 0.015, posteromedial: p = 0.014). The supinated and normal foot groups showed significantly greater reach distances compared to the pronated group (p < 0.026 for anterior direction). In the posterolateral direction, the supinated group demonstrated significantly better performance compared to the pronated group (p = 0.014). Similarly, the posteromedial direction revealed significantly higher reach distances for the supinated group compared to the pronated group (p = 0.012). Conclusion: The study reveals that foot type significantly impacts dynamic balance performance among LSWs. Workers with pronated feet demonstrate reduced balance capabilities, while those with supinated feet show the most superior dynamic balance performance.
Climatic change affects agricultural, environmental and livestock production. Forage productivity is highly dependent on the weather change. The Pyeongchang region has more difficulty in cultivation of Sorghum-Sudangrass hybrids (SSH) than other warm regions because of the cold weather. This experiment was carried out to analysis the agronomic characteristics, productivity, and nutritive value of three cultivars of Sorghum-Sudangrass hybrids in the Pyeongchang region from 2021 to 2022. Two harvests were taken in each year, and the agronomic characteristics, dry matter yield, and nutrient content of the whole SSH crops were determined. The plant height ranged between 281-291 cm and 165-172 cm in the first and second harvest, respectively. Plant height of Superdan (291±49 cm) was the highest in the first cut and Dairy mens Dream (172±30 cm) was the highest in the second cut time. Stem diameter ranged from 9.5 to 8.8 mm with Superdan having a higher level than the other two cultivars. The Dairy mens Dream variety produced significantly higher dry matter yield (15,695 kg/ha) than those of Superdan (14,584 kg/ha) and Supergreen (14,300 kg/ha) over a two-year experimental period. In terms of nutritional quality, the crude protein content, neutral detergent fiber and acid detergent fiber of SSH cultivars were analysed. There were no significant changes in the content of CP, ADF and NDF ranges among the cultivars. In addition, the Superdan cultivar had slightly higher CP content (10.17%) and was followed by Dairy mens Dream (9.84%) and Supergreen (9.54%) in the second cut time of 2-year average. Dairy mens dream had lower ADF and NDF values than other cultivars; however, no significant differences amongst cultivars in fiber content were observed. Therefore, these three cultivars displayed the potential growth characteristics, DM yield and nutritive values in Pyeongchang region. Hence, the SSH cultivars have a potential to withstand the climatic change and improve SSH productivity in the study area.
This study investigates the factors influencing the seed longevity of Quercus myrsinifolia, a species with recalcitrant seeds highly sensitive to desiccation and freezing. The effects of moisture content, seed collection date, and storage methods on seed viability were analyzed using exponential decay modeling. Interactions between these factors were also explored to refine conservation strategies. Seeds with moisture content above 40% demonstrated a predicted seed longevity of 2.19 years, whereas those with moisture content below 30% had seed longevity of less than 1 year. Late-season seeds collected in November and December exhibited superior germination percentages and longer predicted seed longevity (1.32 years) compared to early-season seeds collected in September and October (<1 year). In seed weight, large seeds (2.0 g) showed longer predicted seed longevity about 1.5 times greater than that of small seeds (<1.2g). Storage methods significantly affected seed longevity, with refrigerator (4°C) with silica gel maintaining viability for 2–3 years, while seeds stored at room temperature (25°C) exhibited a seed longevity of less than 1 year. Silica gel was found to prevent seed deterioration due to over-desiccation, emphasizing the importance of balanced moisture regulation. Q. myrsinifolia seeds exhibited 𝑏 values ranging from 0.30 to 2.04, demonstrating a close relationship between decay constant, moisture content, storage conditions, and seed longevity. These findings provide critical insights into optimizing seed storage and propagation strategies for Q. myrsinifolia, contributing to its conservation and ecological restoration efforts.
The Pieris napi-complex in East Asia that comprises P. melete Ménétriés, 1857, P. dulcinea (Butler 1882), and P. nesis (Fruhstorfer 1909) has been taxonomically challenging to distinguish due to their similar appearances. In this study, P. nesis, typically found in central Japan, was discovered in the highlands on Jejudo Island, the southernmost part of the Korean Peninsula. We conducted a molecular phylogenetic analysis using mitochondrial COI gene to explore the relationship between P. dulcinea and P. nesis, and confirmed that P. nesis occurs in Korea. This paper provides the morphological characteristics of P. nesis compared to P. dulcinea, along with DNA data.
Forage crop cultivation and management are the greatest challenge under warm and dry climatic conditions. In this study, we estimated the productivity of three Sorghum-Sudangrass hybrids (SSH) cultivars in Cheonan, Korea, under different weather conditions during 2021-2023. The selected three cultivars performed well in the first and second cutting time during the experimental period and the plant growth characteristics were slightly different among cultivars. Particularly, the plant height was highest in Superdan cultivars (282 ± 24, 271 ± 30 cm), followed by Dairy mens dream (263 ± 39, 283 ± 29 cm) and Supergreen (270 ± 36, 264 ± 34 cm), for the first and second cuts respectively. The stem diameter slightly decreased in the second cut compared with the first cut of SSH cultivars. The highest stem diameter was found in Superdan cultivars (11.1 ± 1.7 mm), greater than Supergreen (10.2 ± 1.7 mm), and Dairy mens dream (9.5 ± 1.8 mm). Also, the total dry matter yield (DMY) was highest in Dairy mens dream (28,868 ± 6,653 kg/ha) followed by Supergreen and Superdan cultivars. In 2021 and 2023, the highest plant height, stem diameter and DMY were measured in the selected cultivars compared to 2022. The crude protein level was higher in the first cutting of all three cultivars at approximately 9-12%, in the order of Supergreen > Dairy mens dream > Superdan varieties. Moreover, the crude protein content was lowest in the second harvest of all cultivars, but the NDF and ADF levels did not alter in both harvest periods across different cultivars and years. In conclusion, the selected cultivars for SSH forage production could be efficient and recommended in the Cheonan region. However, the choice of cutting time and optimum precipitation should be considered to further increase SSH forage cultivation.
Background: South Korea has recently faced record-high temperatures, which have adversely affected dairy production. Holstein cows, the primary dairy breed globally, are particularly sensitive to heat stress. In contrast, Jersey cows have shown greater heat tolerance, as demonstrated by phenotypic studies. Methods: We investigated physiological and molecular responses to heat stress in Holstein and Jersey cows by measuring rectal temperature, milk yield, and average daily gain, confirming Holstein cows’ greater vulnerability. To explore molecular mechanisms, we analyzed circulating microRNA profiles from whole blood samples collected under heat stress and normal conditions using microRNA-sequencing. Differential expression patterns were compared between the two breeds to identify biological pathways associated with heat stress. Results: Four microRNAs (bta-miR-20b, bta-miR-1246, bta-miR-2284x, and bta-miR- 2284y) were significantly differentially expressed in both breeds under heat stress (|FC| ≥ 2, p < 0.05). Notably, bta-miR-20b and bta-miR-1246 were linked to corpus luteum function and progesterone biosynthesis, while bta-miR-2284x and bta-miR- 2284y were associated with immune responses. A comparison of 11 potential heat stress-related microRNAs identified in previous studies of Holstein cows revealed consistent expression trends in Jersey cows, albeit with lower fold changes, suggesting their superior heat resilience. Conclusions: Our study highlights the physiological and microRNA-based differences in heat stress responses between Holstein and Jersey cows. Jersey cows exhibited greater resilience, supported by more stable microRNA expression profiles and improved heat stress indicators, making them a promising breed for dairy production in increasingly hot climates.
This study investigated the morphological characteristics and regional variations of leaves, flowers, and seeds of Quercus myrsinifolia Blume to understand its ecological adaptation and the effects of environmental factors. Samples were collected from Jinju, Hapcheon, and Sancheong, and nine leaf traits, six flower traits, and five seed traits were analyzed. Significant regional variations were observed, with Hapcheon exhibiting the largest leaf and flower sizes, while Sancheong showed the largest and heaviest seeds. Jinju recorded the smallest values for most traits. Principal Component Analysis (PCA) revealed distinct regional groupings, with Hapcheon displaying intermediate traits, Sancheong larger traits, and Jinju smaller traits. Correlation analysis identified strong positive relationships between leaf length and width, seed length and weight, and the number of staminate flowers and catkin width, highlighting key indicators for growth. Climate factors such as temperature and precipitation significantly influenced morphological traits, with higher temperatures negatively affecting leaf and seed sizes, while precipitation showed a weak positive correlation with seed weight. Among soil factors, pH and magnesium content were closely related to morphological traits. pH exhibited a negative correlation with leaf length and petiole length, while magnesium showed a positive correlation with seed weight and leaf width. These findings underscore the significant role of environmental factors in morphological variation and provide valuable insights for developing regionally adaptive breeding strategies. These findings provide foundational data for developing region-specific breeding strategies and cultivars for Q. myrsinifolia, contributing to ecological management and climate change adaptation strategies.
Despite the widespread use of polyaniline as a pseudocapacitor material, the cycling stability and rate capability of polyaniline- based electrodes are of concern because of the structural instability caused by repeated volumetric swelling and shrinking during the charge/discharge process. Herein, nanofiber-structured polyaniline was synthesized onto activated carbon textiles to ensure the long-term stability and high-rate capability of pseudocapacitors. The nanoporous structures of polyaniline nanofibers and activated textile substrate enhanced the ion and electron transfer during charge/discharge cycles. The resulting pseudocapacitor electrodes showed high gravimetric, areal, and volumetric capacitance of 769 F g− 1, 2638 mF cm− 2, and 845.9 F cm− 3, respectively; fast charge/discharge capability of 92.6% capacitance retention at 55 mA cm− 2; and good longterm stability of 97.6% capacitance retention over 2000 cycles. Moreover, a symmetric supercapacitor based on polyaniline nanofibers exhibited a high energy of 21.45 Wh cm− 3 at a power density of 341.2 mW cm− 3 in an aqueous electrolyte.
본 연구는 제주도 모슬포 해역에서 채집된 대형 포식성 복족류인 붉은입두꺼비고둥(Tutufa bufo) 두 개체를 대상 으로 테트로도톡신(TTX) 존재 여부를 조사하였다. 일본에 서 채집된 붉은입두꺼비고둥의 내장에서 TTX가 검출된 사례가 보고된 바 있으며, 최근 제주도 남부 해역에서 해 당 종이 혼획되고 있으나, 한국 해역에 분포하는 붉은입 두꺼비고둥의 TTX 축적에 대한 정보는 부족하다. 이에 본 연구에서는 경쟁적 효소면역분석법(cELISA) 을 사용하여 붉은입두꺼비고둥의 주요 연조직(전타액선, 구강부, 소화 선, 생식소, 아가미, 신장, 근육, 후타액선)을 분석하였다. 분석 결과, 모든 조직에서 TTX 농도는 검출 한계 미만으 로 나타났다. 그러나 TTX 축적에는 개체 간, 지역적, 계 절적 변동 가능성이 존재할 수 있으므로, 한국 해역에서 붉은입두꺼비고둥의 TTX 축적 위험을 정확하게 평가하기 위해서는 추가적인 시료 확보와 계절별 연구가 요구된다.
The world is transitioning towards sustainable agriculture, which includes reducing chemical fertilizers and increasing the adoption of eco-friendly materials. Red clay, known for its colloidal properties, adsorption, and ion exchange capabilities, has become eco-friendly due to its non-toxic nature. However, when red clay is applied in its insoluble powdered form, its absorption by plants is limited. Processed red clay (PRC) was developed to overcome these limitations, and microbial formulations containing Lactobacillus fermentum (MFcL) were applied alongside it. Chlorophyll content and fluorescence values decreased over time after cucumber transplantation. However, co-application of PRC and MFcL resulted in higher chlorophyll content than PRC alone, suggesting that this combination could alleviate plant growth reduction caused by stress. Although the total yield of cucumbers was highest in the NF group, yield per plant increased by more than 10% in the PRC treatment compared to NF. Additionally, yield was higher when PRC was applied alongside MFcL than with MFcL alone. While the proportion of marketable fruits decreased over time in the NF treatment, it increased in the PRC treatment. Soil analysis revealed that PRC application increased soil pH by 3% and available silicon content by 7.6% compared to NF, while available phosphate levels decreased by 13%. Analysis of microbial density in the soil showed that bacteria levels significantly increased by 2-fold in PRC+MFcL compared to NF, while actinomycetes decreased by 1.5-fold. In conclusion, PRC treatment positively influenced cucumber growth, and co-application with microbial fertilizers demonstrated a synergistic effect.