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The Rayleigh limit and low signal-to-noise ratio (SNR) scenarios pose significant limitations to optical imaging systems used in remote sensing, infrared thermal imaging, and space domain awareness. In this study, we introduce a stochastic sub-Rayleigh imaging (SSRI) algorithm to localize point objects and estimate their positions, brightnesses, and number in low SNR conditions, even below the Rayleigh limit. Our algorithm adopts a maximum likelihood approach and exploits the Poisson distribution of incoming photons to overcome the Rayleigh limit in low SNR conditions. In our experimental validation, which closely mirrors practical scenarios, we focus on conditions with closely spaced sources within the sub-Rayleigh limit (0.49–1.00 R) and weak signals (SNR less than 1.2). We use the Jaccard index and Jaccard efficiency as a figure of merit to quantify imaging performance in the sub-Rayleigh region. Our approach consistently outperforms established algorithms such as Richardson–Lucy and CLEAN by 4X in the low SNR, sub-Rayleigh regime. Our SSRI algorithm allows existing telescope-based optical/infrared imaging systems to overcome the extreme limit of sub-Rayleigh, low SNR source distributions, potentially impacting a wide range of fields, including passive thermal imaging, remote sensing, and space domain awareness.

The growth in space activity has increased the need for Space Domain Awareness (SDA) to ensure safe space operations. Imaging and detecting space targets is, however, challenging due to their dim appearance, small angular size/separation, dense distribution, and atmospheric turbulence. These challenges render space targets in ground-based imaging observations as point-like objects in the sub-Rayleigh regime, with extreme brightness contrast but a low photon budget. Here, we propose to use the recently developed quantum-accelerated imaging (QAI) for the SDA challenge. We mainly focus on three SDA challenges (1) minimal a priori assumptions (2) many-object problem (3) extreme brightness ratio. We also present results on source estimation and localization in the presence of atmospheric turbulence. QAI shows significantly improved estimation in position, brightness, and number of targets for all SDA challenges. In particular, we demonstrate up to 2.5 times better performance in source detection than highly optimized direct imaging in extreme scenarios like stars with a 1000 times brightness ratio. With over 10 000 simulations, we verify the increased resolution of our approach compared to conventional state-of-the-art direct imaging paving the way towards quantum optics approaches for SDA.

Intensity interferometry based on Hanbury Brown and Twiss's seminal experiment for determining the radius of the star Sirius formed the basis for developing the quantum theory of light. To date, the principle of this experiment is used in various forms across different fields of quantum optics, imaging, and astronomy. Although the technique is powerful, it has not been generalized for objects at different temperatures. Here, we address this problem using a generating functional formalism by employing the P-function representation of quantum-thermal light. Specifically, we investigate the photon coincidences of a system of two extended objects at different temperatures using this theoretical framework. We show two unique aspects in the second-order quantum coherence function: interference oscillations and a long-baseline asymptotic value that depends on the observation frequency, temperatures, and size of both objects. We apply our approach to the case of binary stars and discuss the advantages of measuring these two features in an experiment. In addition to the estimation of the radii of each star and the distance between them, we also show that the present approach is suitable for the estimation of temperatures as well. To this end, we apply it to the practical case of binary stars Luhman 16 and Spica α Vir. We find that for currently available telescopes, an experimental demonstration is feasible in the near term. Our work contributes to the fundamental understanding of intensity interferometry of quantum-thermal light and can be used as a tool for studying two-body thermal emitters, from binary stars to extended objects.

ABSTRACT Background Data linkage is a method to form a complete data that can provide more abundant information by combining a plurality of different data files. In this study, we construct the matched data combined with Korea Welfare Panel Survey and National Survey of Tax and Benefit by using statistical matching methodology. We aim to provide the empirical and advisable evidence for tax and welfare policy by analyzing about the welfare attitude in accordance with the welfare status of taxpayer or welfare recipient using matched data. Results According to the analysis results, people with dual status of taxpayer above the tax break-even point and welfare recipient due to recent enlargement of welfare programs are relatively more positive about the expansion of the universal welfare than taxpayers who never receive welfare benefit. Also, in the group with dual status, the recognition that the current tax burden of middle class is low is relatively higher and the negative thinking about the need to increase tax burden for the enlargement of the universal welfare programs is relatively lower than the group who pay tax but never receive welfare benefit.

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Mannose-functionalized magnetic nanoparticles were prepared for the immobilization of Escherichia coli cells harboring the recombinant glycerol dehydrogenase gene. Immobilization of whole E. coli cells on the carrier was carried out through specific binding between mannose on the nanoparticles and the FimH lectin on the E. coli cell surface via hydrogen bonds and hydrophobic interactions. The effects of various factors including cell concentration, pH, temperature, and buffer concentration were investigated. High degrees of immobilization (84%) and recovery of activity (82%) were obtained under the following conditions: cell/support 1.3 mg/mL, immobilization time 2 h, pH 8.0, temperature 4°C, and buffer concentration 50 mM. Compared with the free cells, the thermostability of the immobilized cells was improved 2.56-fold at 37 °C. More than 50% of the initial activity of the immobilized cells remained after 10 cycles. The immobilized cells were evaluated functionally by monitoring the catalytic conversion of glycerol to 1,3-dihydroxyacetone (DHA). After a 12 h reaction, the DHA produced by the immobilized cells was two-fold higher than that produced by the free cells. These results indicate that mannose-functionalized magnetic nanoparticles can be used for the specific recognition of gram-negative bacteria, which gives them great potential in applications such as the preparation of biocatalysts and biosensors and clinical diagnosis.

This paper suggests an obstacle avoidance scheme that enables a group of micro-UAV (Unmanned Aerial Vehicles) to avoid colliding with an obstacle that is found in the course of the flight. This scheme considers a method for UAVs to avoid colliding with such obstacles and a plan of action for when the UAVs in the group lose connectivity during flight. The main goal is for UAVs to reach the target without colliding with any obstacles. To achieve this goal, directly after the UAVs avoid the obstacle at a raised altitude above it, they fly at a higher altitude for a while and then descend to their original height. When this approach is judged to be inefficient because the height of the obstacle is too high, the UAVs divide into two groups and move to either side of it while continuing to fly at the same altitude, thereby avoiding the obstacle. Afterwards, they gather into one group again. We verify the proposed scheme and do the performance evaluation by ns-2.

Purpose: To examine community integration and contributing factors in people with aphasia (PWA) following stroke and to investigate the relationship between community integration and quality of life (QOL). Materials and Methods: Thirty PWA and 42 age-and education-matched control subjects were involved. Main variables were as follows: socioeconomic status, mobility, and activity of daily living (ADL) (Modified Barthel Index), language function [Frenchay Aphasia Screening Test (FAST)], depression [Geriatric Depression Scale (GDS)], Community Integration Questionnaire (CIQ) and Stroke and Aphasia Quality of Life Scale-39 (SAQOL-39). Differences between aphasia and control groups and factors affecting community integration and QOL were analyzed. Results: Home and social integration and productive activity were significantly decreased in the aphasia group compared to the control group; 8.5 and 18.3 points in total CIQ score, respectively. Amount of time spent outside the home and frequency of social contact were also significantly reduced in the aphasia group. Total mean score on the SAQOL-39 was 2.75±0.80 points and was significantly correlated with economic status, gait performance, ADL, depressive mood, and social domain score on the CIQ. Depression score measured by GDS was the single most important factor for the prediction of QOL, but the FAST score was significantly correlated only with the communication domain of the SAQOL-39. Conclusion: Community activities of PWA were very limited, and depression was highly associated with decreased community integration and QOL. Enhancing social participation and reducing emotional distress should be emphasized for rehabilitation of PWA. [ABSTRACT FROM AUTHOR]

Intravenous (IV) infusion of oleic acid (OA) distributes OA microemboli in the pulmonary capillaries, which results in severe vascular congestion, hemorrhage vascular congestion, interstitial edema, intravascular coagulation and bleeding. The immune response to acute lung injury (ALI) is known to be associated with rapid and widespread changes in microRNA (miRNA) expression in the lung. The present study of a model of rat lung injury aimed to investigate how the lung miRNA profile changes to mediate ALI. For the induction of ALI, OA (200 μl/kg) suspended in 20% ethyl alcohol was injected through the tail vein for 20 min. Lung tissue samples were acquired at 3, 6 and 24 h, and miRNA microarray and quantitative polymerase chain reaction were performed using these samples. The activation of phosphatase and tensin homolog (PTEN), protein kinase B (Akt), extracellular signal-regulated kinases (ERK) and c-Jun N-terminal kinases (JNK) were analyzed by western blot analysis. There were 75 miRNAs that demonstrated >1.5-fold changes in expression levels. miR-101a was highly upregulated at 3 h. miR-21 was upregulated in the OA group throughout the 24 h following OA challenge. miR-1 was the most downregulated miRNA at 24 h. In order to examine the expression levels of PTEN and Akt as targets of miR-21, western blot analysis was performed. At 3 h, the levels of PTEN were attenuated in the OA group as compared with those in the control group; however, p-Akt/Akt levels were increased at 3 h for the OA group. PTEN and p-Akt/Akt were significantly higher in the OA group at 3 h and were rapidly decreased at 6 h. The immunohistochemical stain of a-smooth muscle actin in the bronchial and alveolar wall increased 24 h after OA-induced ALI. These results indicated that the profile of miRNAs dynamically changed throughout the OA-induced ALI process, and mitogen-activated protein kinase activation, PTEN/Akt pathway alteration and smooth muscle actin activation were observed in this ALI model. [ABSTRACT FROM AUTHOR]

The purpose of this study was to evaluate the reliability and validity of the Junior Temperament and Character Inventory (Junior TCI), a child and adolescent version of the Adult Temperament and Character Inventory (TCI), which is based on Cloninger's biosocial model of personality. The Junior TCI was translated into Korean and administered to 663 Korean middle school students (male/female, 360/303; age, 13.3 ± 1.0 years) and their parents (mother/father, 444184). Internal consistency was calculated by Cronbach α. A test-retest study of the Junior TCI was conducted across a 3-month interval with 97 subjects. Factor analyses for the temperament and character dimensions were performed using principal component analysis, rotating factors by Promax. Cronbach α values of the Junior TCI scales ranged from .48 to .80 for the temperament scales and from .64 to .68 for the character scales. Test-retest correlations ranged from .62 to .85 for the temperament scales and from .76 to .79 for the character scales. Principal component factor analyses showed three factors out of four temperament scales (Harm Avoidance 1 to 4; Novelty Seeking 1 to 4; Persistence; and Reward Dependence 1, 3, 4) and three factors out of three character scales (Self-Directedness 1 to 5; Cooperativeness 1 to 5; and Self-Transcendence 1 to 3) that were similar to factor structures of adult versions of the TCI. Explorative factor analysis with a condition of eigenvalue greater than 1 produced six factors, as compared to seven factors extracted in Cloninger's original report of the adult TCI. In conclusion, this was the first study to tests and report detailed psychometric properties of the Junior TCI. The current study confirms that the Junior TCI has satisfactory psychometric properties for the use in child and adolescent populations and reflects Cloninger's biosocial model of personality. [ABSTRACT FROM AUTHOR]

Objective video quality measurement has become an important issue, as multimedia services are now widely available over the Internet and other wireless communication media. Traditionally, professional CRT monitors have been used to measure subjective video quality. However, the majority of users have LCD, plasma display panel (PDP), or consumer-graded CRT monitors. We compared the subjective video quality of various TV and LCD PC monitors. Subjective tests were performed with a wide range of video sequences using different monitors, and their correlations were analyzed. Although there were high correlations among the various display monitors, care should be taken in selecting a monitor for certain applications. [ABSTRACT FROM AUTHOR]