Galaxy evolution studies require the measurement of the physical properties of galaxies at different redshifts. In this work, we build supervised machine learning models to predict the redshift and physical properties (gas-phase metallicity, stellar mass, and star formation rate) of star-forming galaxies from the broad-band and medium-band photometry covering optical to near-infrared wavelengths, and present an evaluation of the model performance. Using 55 magnitudes and colors as input features, the optimized model can predict the galaxy redshift with an accuracy of σ(Δz/1+z) = 0.008 for a redshift range of z < 0.4. The gas-phase metallicity [12 + log(O/H)], stellar mass [log(Mstar)], and star formation rate [log(SFR)] can be predicted with the accuracies of σNMAD = 0.081, 0.068, and 0.19 dex, respectively. When magnitude errors are included, the scatter in the predicted values increases, and the range of predicted values decreases, leading to biased predictions. Near-infrared magnitudes and colors (H, K, and H −K), along with optical colors in the blue wavelengths (m425–m450), are found to play important roles in the parameter prediction. Additionally, the number of input features is critical for ensuring good performance of the machine learning model. These results align with the underlying scaling relations between physical parameters for star-forming galaxies, demonstrating the potential of using medium-band surveys to study galaxy scaling relations with large sample of galaxies.
본 연구는 절화 국화의 수경재배와 토경관비재배 시 생육 특 성을 비교하기 위하여 실시하였다. 그 결과 초장, 절화의 생체중 과 건물중은 토경관비재배에서 증가하였다. 식물체 내 전질소, 칼륨 및 칼슘의 함량도 토경관비재배에서 더 높았다. 반면에 줄기 직경은 수경재배에서 3.7mm로 증가하였다. 또한 개화소 요일수도 토경관비재배보다 수경재배에서 3일 정도 단축되었 고, 줄기 1개당 꽃 수도 19.6개로 수경재배에서 더 많았다. 결과 적으로 토경관비재배에서 식물체 내 무기염류 함량이 높고, 초장이 길어지고 생체중, 건물중이 증가하였지만 수경재배보다 개화기는 지연되었다. 또한 토경관비재배보다 수경재배에서 줄 기 직경이나 꽃 수 등이 증가하였다. 따라서 재배자의 입장에서 국화 수경재배를 통해 양분과 수분 공급량의 조절에 의한 개화 기의 조절, 조기 개화 및 절화 품질 향상 등의 효과를 기대할 수 있을 것으로 판단된다.
Following the previous study, which investigated the pharmacological properties of the Technekitty injection (Tc-99m), the toxicity of a single intravenous administration of the Technekitty injection (Tc-99m) and the side effects that may occur at the diagnostic dose were confirmed. The Technekitty injection (Tc-99m) was administered intravenously once at a dose of 0, 0.67, 2.0, and 6.0 mCi/kg to 5 male and female rats per group. Mortality, general symptom observation, and weight measurement were performed for 2 weeks, followed by observation of autopsy findings. There were no deaths, and no statistically significant weight change was observed. No abnormal systemic signs related to the Technekitty injection (Tc-99m) were observed. These results confirmed that Technekitty injection (Tc-99m) can be safely administered intravenously at doses up to 6.0 mCi/kg. Additionally, technetium-99m at an average dose of 2 mCi (74 MBq) has been verified as a diagnostic dose without adverse effects, allowing the Technekitty injection (Tc-99m) to be used safely without side effects at this dosage. This study demonstrates that the Technekitty injection (Tc-99m) has a wide safety margin, supporting its potential for clinical application. Moreover, these findings align with the nonclinical safety standards for radiopharmaceuticals, reinforcing its utility in veterinary medicine. The Technekitty injection (Tc-99m) is expected to be applicable for clinical diagnosis as a veterinary drug in Korea.
Thyroid scanning using technetium-99m (99mTc) is the gold standard for diagnosing feline hyperthyroidism. In cats with an overactive thyroid, a thyroid scan is the most appropriate imaging technique to detect and localize any hyperfunctional adenomatous thyroid tissue. In this study, the pharmacological properties of the Technekitty injection (Tc-99m), developed as a diagnostic agent for feline hyperthyroidism using 99mTc as an active ingredient, were tested in FRTL-5 thyroid follicular cell line and ICR mice. The percentage of cell uptake of the Tc-99m in FRTL-5 thyroid cells was 0.182 ± 0.018%, which was about 6 times higher compared to Clone 9 hepatocytes. This uptake decreased by 38.2% due to competitive inhibition by iodine (sodium iodide). In tissue distribution tests by using ICR mice, the highest distribution was observed in the liver, kidneys, spleen, lungs, and femur at 0.083 hours after administration, and this distribution decreased as the compound was excreted through the kidneys, the primary excretory organ. Maximum distribution was confirmed at 1 hour in the small intestine, 6 hours in the large intestine, and 2 hours in the thyroid gland. Additionally, the total amount excreted through urine and feces over 48 hours (2 days) was 78.80% of the injected dose, with 37.70% (47.84% of the total excretion) excreted through urine and 41.10% (52.16% of the total excretion) through feces. In conclusion, the Tc-99m has the same mechanism of action, potency, absorption, distribution, metabolism, and excretion characteristics as 99mTc used for feline hyperthyroidism in the United States, Europe, and other countries, because the Technekitty injection (Tc-99m) contains 99mTc as its sole active ingredient. Based on these results, the Technekitty injection (Tc-99m) is expected to be safely used in the clinical diagnosis of feline hyperthyroidism.
본 연구의 목적은 밀레니얼 세대의 조직몰입을 증진시킬 수 있는 요인을 밝히고 해당 변인들 간의 관 계를 알아보는 것이다. 구체적으로 윤리적 리더십이 밀레니얼 세대의 조직몰입에 영향을 미치는 경로에 서 일 의미감 7가지 하위요인의 매개효과를 검증하였으며, 연구문제에 따라 소속감, 잠재력의 표현, 영감 요인 등 세 가지 하위요인을 중심으로 매개효과를 살펴보았다. 이를 위해 대한민국 MZ세대 직장인 212명을 대상으로 윤리적 리더십 척도, 일 의미감 척도, 조직몰입 척도를 활용하여 설문을 실시하였다. 연구결 과는 다음과 같다. 첫째, 윤리적 리더십, 일 의미감 7가지 하위요인, 조직몰입 간 상호 유의한 상관관계를 확인하였다. 둘째, 윤리적 리더십은 MZ세대 직장인의 조직몰입에 통계적으로 유의미한 영향을 미치는 것을 확인하였다. 마지막으로, 윤리적 리더십이 조직몰입에 영향을 미치는 경로에서 일 의미감의 매개효 과를 살펴본 결과, 소속감과 영감 요인이 두 변인의 관계를 매개하는 것으로 나타났다. 이러한 결과는 MZ 세대가 리더를 윤리적으로 인식할수록 조직에 대해 높은 소속감을 지각하는 동시에 리더로부터 영감과 같은 긍정적 영향력을 받아 조직에 더욱 몰입할 수 있음을 시사한다. 이와 같은 결과를 바탕으로 시사점, 한계점과 후속연구의 필요성에 관하여 논의하였다.