Research & Development Institute

Abstract Green tides – massive proliferations of green macroalgae ( Ulva spp.) – have increasingly occurred worldwide in recent years, driven by accelerating climate change and anthropogenic nutrient inputs. These blooms disrupt coastal ecosystems, leading to biodiversity loss and economic damage. In Korea, green tides have persisted on Jeju Island since the 2000s, and have also been sporadically reported on the southern mainland coasts. However, the specific Ulva species responsible for these blooms remain largely unknown. Here, we investigated Ulva community structure and relative frequencies from 46 sites (966 specimens) on Jeju Island and the southern coasts, using chloroplast tuf A gene-based phylogenetic analysis, complemented by additional nuclear 5s rDNA marker. We found considerable differences in Ulva community composition between Jeju Island and the southern coasts, along with pronounced seasonal variation. On Jeju Island, nine Ulva species were found, with Ulva ohnoi and Ulva australis dominant, whereas 10 species were observed with U. australis and Ulva linza prevailed on the southern coasts. The presence of nonindigenous Ulva species highlights the need for continuous monitoring to track their spread and biomass growth. Our results provide essential genetic insights to support effective management of green tide events in Korean coastal ecosystems.

The results of experimental studies on the creation of a force measuring device for measuring thrust during firing tests of rocket engines in continuous and pulse modes are presented. Characteristics of the device operation for horizontal and vertical degrees of freedom in space were analyzed. The studies showed that placing the device horizontally is preferable, as it gives more reliable results with the shortest time of response to calibration forces from an electromagnetic inverse converter compared to vertical placement when determining dynamic characteristics. The operation of a force-measuring device was tested during firing tests of a rocket engine.

Fast operating speed and low power consumption are critical attributes for effective beam steering of high-performance focal plane arrays (FPAs). Here, we establish an integrated FPA chip based on the electro-optical (EO) effect of thin-film lithium niobate (TFLN) to access these outstanding performances. By leveraging the advantages of the EO effect of TFLN, we showcase an ultrafast operating speed of 25.9 ns and an ultralow power consumption of 35.8 nJ/π, which are 3 and 2 orders of magnitude smaller than those of conventional FPAs, respectively. Our experimental results demonstrate a two-dimensional (2D) beam steering with a field of view (FoV) of 1.48° × 1.95°, a beam divergence of 0.036° × 0.043°, and a background suppression ratio exceeding 20 dB. Furthermore, we present the elimination of blind zones in one direction and the potential application of laser projection of proposed EO FPA. This work demonstrates the remarkable advantages of the EO effect of the TFLN platform for developing fast-speed and low-power-consumption FPA chips suitable for a variety of beam-steering applications.

The coded-aperture gamma camera has significant applications in the fields of space exploration, nuclear security, nuclear industry, and nuclear medicine. The coded-aperture collimator is a key component for modulating gamma rays, and its parameters are important factors to optimize the performance of gamma cameras. In this paper, the impact of collimator thickness on the fully coded field of view and angular resolution was determined through Monte Carlo simulation and experimental verification. By introducing the equivalent thickness, the conventional calculation formulas were modified to improve the calculation accuracy. In addition, the variation in the reconstructed image quality with the collimator thickness was quantitatively evaluated by the contrast-to-noise ratio and normalized mean squared error, thereby establishing the relationship between the gamma-ray transmittance and the imaging quality. The results indicate that for medium- and high-energy gamma rays, the optimal imaging quality is achieved when the gamma-ray transmittance corresponding to collimator thicknesses ranges from 12% to 16%. These research findings provide reference standards for the design of coded-aperture collimators to meet the requirements of different applications.

594 Background: Kidney injury molecule-1 (KIM-1) is a circulating biomarker for renal cell carcinoma. The JAVELIN Renal 101 trial established avelumab and axitinib as a standard treatment regimen for advanced renal cell carcinoma (aRCC). In this post-hoc analysis, we evaluated whether baseline plasma KIM-1 and KIM-1 change on treatment are associated with outcomes in JAVELIN Renal 101. Methods: Patients with aRCC were randomized to avelumab plus axitinib (Av/Ax) or sunitinib (Sun), as previously described. KIM-1 was measured in plasma at baseline (C1D1) and at C3D1 using a Luminex microbead-based assay and an MSD electrochemiluminescence-based assay. KIM-1 values were categorized into high and low according to an optimized cutoff based on the maximum log-rank Q-statistic for PFS. Cox regression analyses were performed for OS and PFS and adjusted for baseline clinical characteristics. Associations between KIM-1 levels and clinical and transcriptomic data were evaluated using the Wilcoxon rank-sum test. Results: Plasma for analysis was available from 612 patients (69% of the ITT population), including 323 treated with Av/Ax and 289 with Sun. 57% of patients had high KIM-1 at baseline. In all patients, lower circulating KIM-1 at baseline was associated with longer progression-free survival (PFS) and overall survival (OS) (Table). Baseline KIM-1 levels were significantly lower in angiogenic (1-2) vs immune (4-5) transcriptomic clusters (p=0.002), responders vs non-responders (p=0.01), and exceptional vs intermediate responders (p=0.0015). In paired analyses, circulating KIM-1 decreased from baseline to C3D1 (p<0.0001) in both arms. Decrease in KIM-1 from baseline to C3D1 was associated with longer PFS and OS (Table). Luminex and MSD antibody-based assays had good concordance for distinguishing higher vs lower KIM-1 when measured in the same samples (Spearman’s ρ = 0.737), but absolute values of KIM-1 differed between the two assays (p<0.0001). Conclusions: This is the first study to evaluate circulating KIM-1 among patients with aRCC receiving immune checkpoint inhibitor and VEGF tyrosine kinase inhibitor combination therapy. Lower baseline plasma KIM-1 and decrease during treatment were associated with better prognosis. The distribution of circulating KIM-1 is assay-dependent and standardized cutoffs are needed before KIM-1 can be used in clinical decision making. Association of baseline KIM-1 and KIM-1 change on treatment with outcomes. Entire CohortHR (95% CI) SunitinibHR (95% CI) Avelumab + AxitinibHR (95% CI) PFS(KIM-1 low vs high) 0.76 (0.58–0.99) 0.67 (0.47–0.95) 0.88 (0.61–1.28) OS(KIM-1 low vs high) 0.58 (0.38–0.88) 0.46 (0.26–0.81) 0.79 (0.43–1.47) PFS(KIM-1 decrease vs increase) 0.65 (0.46–0.87) 0.66 (0.46–0.96) 0.79 (0.48–1.30) OS(KIM-1 decrease vs increase) 0.58 (0.39–0.88) 0.79 (0.46–1.35) 0.45 (0.46–0.89) HR: hazard ratio; CI: confidence interval.

A study was carried out in the case of experiments on soil Works located at Padina, Mehedinti county (Romania), on a soil of reddish Preluvosol type with a texture on the depth of 5-10 cm, medium clay and clay loam on the sampling depths 25-30 cm and 45-50 cm). The apparent density was significantly affected by the soil works systems, with the lowest values for the conventional system on the depth of 5-10 cm, and on the depth of 25-30 cm, the highest values being recorded in minimum tillage. This difference is given by the higher clay content. The degree of susceptibility of reddish Preluvosol for the two systems of works is moderately susceptible for conventional and unsusceptible for conservative, due to the preservation of plant debris at the soil surface.