We present a new fiber assignment algorithm for a robotic fiber positioner system in multi-object spectroscopy. Modern fiber positioner systems typically have overlapping patrol regions, resulting in the number of observable targets being highly dependent on the fiber assignment scheme. To maximize observable targets without fiber collisions, the algorithm proceeds in three steps. First, it assigns the maximum number of targets for a given field of view without considering any collisions between fiber positioners. Then, the fibers in collision are grouped, and the algorithm finds the optimal solution resolving the collision problem within each group. We compare the results from this new algorithm with those from a simple algorithm that assigns targets in descending order of their rank by considering collisions. As a result, we could increase the overall completeness of target assignments by 10% with this new algorithm in comparison with the case using the simple algorithm in a field with 150 fibers. Our new algorithm is designed for the All-sky SPECtroscopic survey of nearby galaxies (A-SPEC) based on the K-SPEC spectrograph system, but can also be applied to similar fiber-based systems with heavily overlapping fiber positioners.

This study developed a calibration model using near-infrared spectroscopy (NIR) for the rapid and non-destructive prediction of functional components—total polyphenols, total flavonoids, and antioxidant activities—in sweetpotato. Analysis of 473 sweetpotato genetic resources revealed significant variation and diversity in total polyphenols (4.67 to 2,419 mg/100g, CV 74.26%), total flavonoids (7.71 to 1,057.67 mg/100g, CV 122.88%), DPPH radical scavenging activity (7.83 to 532.56 mg/100g, CV 111%), and ABTS radical scavenging activity (11.84 to 615.87 mg/100g, CV 70.02%). The NIR spectra (400 to 2,500 nm), following pretreatment and modified partial least squares (MPLS) regression, were utilized to create the calibration model. Cross-validation indicated high predictive performance for total polyphenols (R2 cv 0.895), total flavonoids (0.940), DPPH (0.955), and ABTS (0.940). External validation yielded R2 ev values ranging from 0.623 to 0.726 and RPD values between 1.58 and 2.13, confirming the model's practical applicability for large-scale screening and classification. However, further enhancements are needed to improve the accuracy of quantitative analysis. Future studies should focus on refining the predictive model by incorporating samples from diverse genetic resources and cultivation environments. This research demonstrates that NIR spectroscopy can be effectively employed for the rapid, non-destructive evaluation of sweetpotato functional quality, facilitating the efficient selection of high-value cultivars.

Airborne microplastics (AMPs), known to be persistent pollutants, have recently been detected in the atmosphere and even in human lung tissue, raising concerns about potential human respiratory exposure. In light of these concerns, this study aimed to investigate the distribution and composition of AMPs in Seoul. μ-Raman spectroscopy was employed to identify fine particles (≥5 μm) and to contribute to the development of standardized monitoring protocols. Monthly air sampling was conducted from September 2023 to March 2024 at an urban rooftop site using a PM10 air sampler. Samples were pretreated with hydrogen peroxide to remove organic matter, then filtered through a silicon filter. μ-Raman spectroscopy was applied for qualitative and quantitative analysis of microplastics. The mean concentration of AMPs was 74.0 ± 29.9 particles/m3, with polyethylene (46.7%) and polystyrene (21.8%) being the most prevalent polymer types. Most particles (64.5%) were in the size range of 5–10 μm, and fragment type particles accounted for 98.9% of the total. These results indicate that respirable microplastics are commonly present in urban air and that polymer composition may reflect both material properties and usage patterns. This research provides baseline data for future exposure and risk assessments and supports the need for international standardization of airborne microplastic analysis protocols.

목적 : 본 연구는 기능적 근적외선 분광법(functional Near-Infrared Spectroscopy; fNIRS) 기반 하이퍼스캐 닝 기술을 활용하여 측정된 상호 신경 동기화(Interpersonal Neural Synchronization; INS)가 사회적 상호작용의 신경생리학적 지표로 활용될 수 있는지를 탐구하고자 하였다. 또한 INS가 사회적 상호작용 기술 의 임상적 도구로서 활용될 수 있는 근거를 탐색하고자 한다. 연구방법 : 본 연구는 2020년 1월부터 2025년 1월까지의 기간동안 Embase, EBSCO, PubMed, Scopus, Web of Science 데이터베이스에 검색어 “fNIRS”, “hyperscanning”, “interpersonal neural synchronization”, “interpersonal brain synchronization”, “brain-to-brain coupling”, “interactive brain activity”를 사용하여 선정기준 및 배제기준에 따라 최종적으로 49편의 문헌이 선정되었다. 결과 : 선정된 문헌을 분석한 결과, 대부분이 HbO 신호를 기반으로 WTC 분석을 수행하였다. 비뚤림 위험 평가에서는 노출 측정 등 항목에서 낮은 비뚤림 위험이 지배적이었으나, 대상자군 비교 가능성과 교란변수 통제 항목에서는 높은 비뚤림 위험이 다수 확인되었다. INS 반응은 과제 유형에 따라 다르게 나타났으며, 협력, 감정 교류, 경쟁적 상호작용 조건에서 DLPFC, rTPJ, mPFC 등에서의 INS 증가가 관찰되었다. 결론 : 본 연구는 INS가 사회적 상호작용에서 유의미한 신경 지표임을 확인하였으며, 이를 통해 인간의 사회적 뇌를 이해하는 데 있어 유의미한 증거를 제공한다. 또한, 인간의 사회적 인지 과정을 정량화하고 해석할 수 있는 새로운 가능성을 열어주며, 이는 향후 상호작용 중심의 신경과학 연구뿐 아니라, 작업치료 임상 현장에서의 중재 평가 및 설계에 있어 INS의 실용적 활용 가능성을 제시한다.

Near infrared reflectance spectroscopy (NIRS) is widely used to assess the nutrient composition of forages. In forage, the leaf to stem ratio of alfalfa greatly affects its forage quality, with a high ratio of leaf indicated as high quality. This study aimed to evaluate the predictability of the alfalfa leaf-to-stem ratio and feed value using NIRS. Alfalfa hay was manually separated into leaves and stems by hand and the analysis samples were then made in the controlled range between 0 and 100%. Calibration models (n=320) were developed using modified partial least squares regression (MPLS) based on cross-validation. The optimal calibrations were selected based on the highest coefficients of determination in cross-validation (R2) and the lowest standard error of cross-validation (SECV). The prediction accuracy for the leaf-to-stem ratio (SECV, 5.95 vs. 5.71%; R2, 0.91 vs. 0.91) in alfalfa hay was comparable. For leaves, the standard error of calibration (SEC) was 4.94% (R2=0.94), and for stems, it was 4.81% (R2=0.94). The leaves and stems of the SEC were 4.94% (R2=0.94) and 4.81% (R2=0.94), respectively. The prediction accuracy for feed value, based on the leaf-to-stem ratio, predicted SECV values of 0.92% (R2=0.88) for crude protein (CP) content, 1.92% (R2=0.91) for neutral detergent fiber (NDF) content, 1.36% (R2=0.91) for total digestibility nutrient (TDN) content, and 9.86 (R2=0.81) for relative feed value (RFV). The results of this study demonstrate the potential of the NIRS method as a reliable tool for predicting the leaf-to-stem ratio of alfalfa hay, and show available techniques for routine feed value evaluation.

경동맥의 치료 초음파 자극이 뇌의 생리적인 작용에 미치는 영향은 여전히 연구가 필요한 상황이다. 이에 본 연구 에서는 치료용 초음파를 이용한 비침습적이고, 정량적인 열자극 기법을 이용하여 경동맥의 자극을 통해 뇌의 생리적 인 기능을 개선하고 건강한 뇌 기능을 유지할 수 있는 방법을 제안하고자 하였다. 건강한 20대 성인 남녀 27명을 대상으로 연구를 진행하였다. 바로 누운 자세에서 진단용 초음파를 이용하여 우측 총경동맥(right common carotid artery, CCA)의 자극 위치를 확인하고, 우측 목빗근(sternocleidomastoid muscle)에 치료 초음파 자극을 적용하였다. 치료 초음파 자극은 치료용 초음파를 이용하여 3MHz의 주파수에서 총 2가지 강도 (5W/cm2 and 10W/cm2)에서 각각 2분 동안 중재하였다. 근적외선분광법(near-infrared spectroscopy, NIRS)을 이용하 여 대뇌산소포화도(regional cerebral oxygen saturation, rSO2) 및 헤모글로빈(hemoglobin, Hb) 농도의 변화를 측정 하여 비교하였으며, 추가적으로 강도에 따른 중재 구간별 변화를 비교 분석하였다. 두피와 대뇌피질 사이(Shallow) 영역에서 rSO2는 강도에 따라서 서로 증감이 다르게 나타났다. 즉, 5W/cm2에서는 중재전과 비교하여 중재중과 중재후에 모두 감소하는 경향을 보였고, 10W/cm2에서는 모두 증가하는 경향을 보였지 만, 모두 통계적으로 유의한 차이를 보이지는 않았다. 반면, 대뇌피질(Deep) 영역에서는 중재중에서 강도와 상관없이 통계적으로 유의한 감소를 보였고(p = .001 for 5W/cm2; p < .001 for 10W/cm2), 중재중과 비교하여 중재후에는 다시 중재전의 상태로 회복되는 경향을 보였다(p = .016 for 5W/cm2; p = .012 for 1 0W/cm2). 옥시헤모글로빈 (oxyhemoglobin, HbO)의 변화는 5W/cm2 자극에서 중재중에서만 유의한 증가를 보였고(p = .036), 디옥시헤모글로 빈(deoxyhemoglobin, HbR)은 감소하는 경향을 나타냈지만, 유의한 차이를 보이지는 않았다. 10W/cm2 자극에서 HbO와 HbR이 모두 감소하는 경향을 보였지만, 유의한 차이를 보이지 않았다. 강도에 따른 변화는 Shallow 영역에 서 rSO2가 유의한 차이를 보였다(중재중, p = .023; 중재후, p = .022). 결론적으로 3MHz의 주파수와 5W/cm2와 10W/cm2 강도로 중재를 수행하게 된다면, 중재중에 Deep 영역의 rSO2 의 감소를 야기한다는 것을 볼 수 있었다. 10W/cm2의 강한 강도의 자극에서는 Shallow 영역에서 rSO2가 증가하고, Deep 영역에서는 감소하는 것을 보여주었다. 이는 강한 강도의 자극에 의해 내경동맥의 혈류 증가로 인한 대뇌피질 에서의 효과적인 자극이 아니라 외경동맥의 혈류 증가로 인하여 Shallow 영역에서의 혈류 공급의 과다로 인한 현상 이 나타난 것으로 보여 진다. 반면, 대뇌에서 HbO는 5W/cm2의 강도에서 증가하였고, 이는 전반적인 산소 공급량이 높아졌음을 의미한다. 이에 적절한 강도의 치료용 초음파 자극을 사용한다면 기존에 알려져 있던 뇌혈류의 개선을 통하여 뇌혈관 건강을 개선하는 기능과 더불어 대뇌의 생리적인 기능을 조절하여 뇌기능의 개선에 기여할 수 있을 것으로 보인다.

La modified lead zirconate titanate ceramics (Pb0.92La0.08)(Zr0.95Ti0.05)O3 = PLZT-8/95/5 were prepared using the conventional solid state reaction method in order to investigate the complex impedance characteristics of the PLZT-8/95/5 ceramic according to temperature. The complex impedance in the PLZT-8/95/5 ceramic was measured over a temperature range of 30~550 °C at several frequencies. The complex dielectric constant anomaly of the phase transition was observed near TU1 = 179 °C and TU2 = 230 °C. A remarkable diffuse dielectric constant anomalous behaviour of the complex dielectric constant was found between 100 °C and 550 °C. The complex impedance spectra below and above TU1 and TU2 were fitted by the superposition of two Cole-Cole types of impedance relaxations. The fast component in the higher frequency region may be due to ion migration in the bulk, and the slow component in the lower frequency region is interpreted to be the formation and migration of ions at the grain boundary or electrode/crystal interfacial polarization.

Fulvic acid, a humic substance with unique properties, has sparked interest due to its potential applications in the treatment of allergic diseases, Alzheimer's disease, and as a microplastic adsorbent. However, conventional extraction methods produce insufficient quantities for commercial use, which has prompted research to enhance fulvic acid production. In this study, we investigated the impact of Saccharomyces cerevisiae fermentation on the yield and spectral characteristics of fulvic acid extracted from white peat. Fulvic acid was extracted from both S. cerevisiae-treated and untreated white peats using acid precipitation. The yield of fulvic acid from the S. cerevisiae treated group reached its highest at 3.5 % after 72 hr of fermentation, which was significantly higher than the untreated group (1.1 %). Fourier Transform Infrared (FTIR) analysis revealed similarities in functional groups and characteristic absorption bands between the treated and untreated fulvic acid samples. These findings suggest that S. cerevisiae fermentation can increase the yield of fulvic acid extracted from white peat, providing a promising approach for enhancing the commercial viability of fulvic acid production.