Polarization Angle Dependence of Optical Gain in a Hybrid Structure of Alexa-Flour 488/M13 Bacteriophage

We measured optical modal gain of a dye–virus hybrid structure using a variable stripe length method, where Alexa-fluor-488 dye was coated on a virus assembly of M13 bacteriophage. Inspired by the structural periodicity of the wrinkle-like virus assembly, the edge emission of amplified spontaneous emission was measured for increasing excited optical stripe length, which was aligned to be either parallel or perpendicular to the wrinkle alignment. We found that the edge emission showed a strong optical anisotropy, and a spectral etalon also appeared in the gain spectrum. These results can be attributed to the corrugated structure, which causes a similar effect to a DFB laser, and we also estimated effective cavity lengths

Evaluation of Agricultural Water Supply and Selection of Deficient Districts in Yeongsan River Basin of South Korea Considering Supply Priority

Considering the priority of water supply, agricultural water supply capacity downstream of the Yeongsan River Basin was evaluated in this study. The water balance was analyzed using the Please check all author names carefullyMODSIM-decision support system (MODSIM-DSS) to evaluate the agricultural water supply capacity. MODSIM-DSS can also be used to analyze the watershed demand status and agricultural water supply facilities. In this study, the watershed inflow and agricultural reservoir inflow (supply) data for each watershed were obtained using the SWAT outflow data. SWAT was calibrated and validated using 16-years (2005-2020) of daily streamflow data from one water level station and two weirs, by considering water withdrawal and return flows from agricultural, domestic, and industrial water use. The coefficient of determination (R-2) was analyzed as 0.50 to 0.80 at three stations. Then, water balance analyses were performed for 41 years (1980-2020) by applying the SWAT outflow results to MODSIM-DSS. The results showed that agricultural water shortages of 517.8 x 10(6) m(3), 520.0 x 10(6) m(3), 579.8 x 10(6) m(3), and 517.5 x 10(6) m(3), occurred in 1992, 1994, 1995, and 2015, respectively. The efficiencies of agricultural water supply for these years were 58.2%, 58.0%, 53.2%, and 58.2%, respectively, which were lower than the 40-year average of 84.5%.N

Assessment of Agricultural Drought Vulnerability with Focus on Upland Fields and Identification of Primary Management Areas

Robust water management systems are crucial for sustainable water use, particularly considering rapidly changing, ever-improving water supply system technologies. However, the establishment of specific management standards in upland fields is challenging, as several types of crops are cultivated in upland fields. Hence, the timing and required amount of water vary greatly, further rendering drought response challenging. In this study, we evaluated the agricultural drought vulnerability of South Korean upland fields, considering the lack of water resources, to establish preliminary drought damage prevention measures. The Technique for Order of Preference method was used for the drought vulnerability assessment, and the assessment indicators used were annual rainfall, number of dry days, upland field area, available soil water capacity, and groundwater usage. The 20 areas of highest vulnerability comprised large cultivation areas with minimal subsurface-water usage, except for areas where the number of dry days appeared to be the major factor for drought vulnerability. Damage caused by recurring droughts accumulated over time; thus, upland-field-oriented management may be required and can even be used in cases where insufficient drought information is available. Future studies can use the proposed method while considering assessment factors that describe upland field conditions.Y

Elliptical Polarization of Localized States in an Anisotropic Single GaAs Quantum Ring

Localized states in an anisotropic single GaAs quantum ring were investigated in terms of polarization dependence of micro-photoluminescence spectrum at 5K. Given four Stokes parameters measured with a pair of linear polarizers and waveplates, the elliptical polarization states of two different vertical confinement states (k=1 and k=2) were compared with phase, rotation, and ellipticity angles. While the polarized emission intensity of the k=2 states becomes enhanced along [1,1,0] compared to that along [1,1¯,0], the polarization asymmetry of the k=1 states shows the opposite result. We conclude the polarization state is determined by the shape of the lateral wavefunctions. In the k=2 state, crescent-like wavefunctions are strongly localized, but the k=1 state consists of two crescent-like wavefunctions, which are connected weakly through quantum tunneling

Optical Gain of Vertically Coupled Cd_0.6Zn_0.4Te/ZnTe Quantum Dots

The optical modal gain of Cd0.6Zn0.4Te/ZnTe double quantum dots was measured using a variable stripe length method, where large and small quantum dots are separated with a ZnTe layer. With a large (~18 nm) separation layer thickness of ZnTe, two gain spectra were observed, which correspond to the confined exciton levels of the large and small quantum dots, respectively. With a small (~6 nm) separation layer thickness of ZnTe, a merged single gain spectrum was observed. This can be attributed to a coupled state between large and small quantum dots. Because the density of large quantum dots (4 × 1010 cm−2) is twice the density of small quantum dots (2 × 1010 cm−2), the density of the coupled quantum dots is determined by that of small quantum dots. As a result, we found that the peak gain (123.9 ± 9.2 cm−1) with the 6 nm separation layer is comparable to that (125.2 ± 29.2 cm−1) of the small quantum dots with the 18 nm separation layer

Optical nanotopography of fluorescent surfaces by axial position modulation

International audienc

Formation of Water Soluble Wavelength Tunable InGaP and InP Quantum Dots

Quantum dots (Q-dots) have recently attracted interest for biological applications as efficient biomarkers. Operational wavelength and water solubility are core considerations in terms of the applicable to Q-dots in biology. However, operating wavelength control and PL loss during water solubilization are major drawbacks. Herein, high quality, wavelength tuneable, and water soluble InGaP and InP were prepared using a simple thermal synthesis. The results obtained showed that the decrease in quantum yield previously observed in lipidized quantum dots loss was greatly diminished using this approach, which resulted in excellent control of emission wavelength and enhanced PL intensity. Q-dot sizes were controlled using a two-step etching process that enabled size control, significantly improved PL intensities, and minimized the loss in PL intensity associated with lipidization

Development of a Component-Based Modeling Framework for Agricultural Water-Resource Management

Because hydrologic responses of an agricultural watershed are influenced by many natural and man-made factors including pond/reservoir, management practices, and/or irrigation/drainage, strategies of hydrological modeling for the watershed must be case-dependent and thus carefully designed to effectively reflect their roles as critical hydrologic components in simulation processes. In this study, we propose a component-based modeling framework that accommodates a flexible modeling approach to consider a variety of hydrologic processes and management practices, especially irrigation-reservoir operation and paddy-farming practices, in watershed-scale modeling. The objectives of this study are twofold: to develop a COmponent-based Modeling Framework for Agricultural water-Resources Management (COMFARM) using an object-oriented programming technique, and to evaluate its applicability as a modeling tool to predict the responses of an agricultural watershed characterized with diverse land uses in a case study. COMFARM facilitates quick and easy development of watershed-specific hydrologic models by providing multiple interchangeable simulation routines for each hydrologic component considered. COMFARM is developed with the JAVA programming language, using Eclipse software. The framework developed in this study is applied to simulating hydrologic processes of the Seon-Am irrigation-district watershed consisting primarily of reservoir-irrigated rice paddies in South Korea. The application study clearly demonstrates the applicability of the framework as a convenient method to build models for hydrologic simulation of an agricultural watershed. The newly developed modeling framework, COMFARM is expected to serve as a useful tool in watershed management planning by allowing quick development of case-oriented analysis tools and evaluation of management scenarios customized to a specific watershed

Polarization Angle Dependence of Optical Gain in a Hybrid Structure of Alexa-Flour 488/M13 Bacteriophage

We measured optical modal gain of a dye–virus hybrid structure using a variable stripe length method, where Alexa-fluor-488 dye was coated on a virus assembly of M13 bacteriophage. Inspired by the structural periodicity of the wrinkle-like virus assembly, the edge emission of amplified spontaneous emission was measured for increasing excited optical stripe length, which was aligned to be either parallel or perpendicular to the wrinkle alignment. We found that the edge emission showed a strong optical anisotropy, and a spectral etalon also appeared in the gain spectrum. These results can be attributed to the corrugated structure, which causes a similar effect to a DFB laser, and we also estimated effective cavity lengths