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In this paper, the performances of spaceborne bistatic synthetic aperture radar (SAR) systems are evaluated and compared with those of the conventional monostatic SAR system. Drawing on information on the altitude of satellites and the pulse repetition frequency of the system, the distance between the satellites carrying the transmitter and the receiver is first determined to then obtain the maximum observable width by overlapping the blind ranges. The performances of the bistatic SAR for two satellites at the same altitude moving parallel to each other at the same speed are evaluated, and the results are compared with those obtained from a monostatic SAR system located at left or right end of the baseline. The resolutions, noise equivalent sigma zero, and ambiguities of the bistatic SAR are evaluated based on the windows between blind incident angles of a timing diagram. Subsequently, the most ap-propriate window is determined by comparing the evaluated performances of the bistatic SAR. [ABSTRACT FROM AUTHOR]

Background: Clinical management of patients infected with hepatitis B virus (HBV) or hepatitis C virus (HCV) relies on the viral load (VL). The Cobas 5800 system (Roche Diagnostics) can determine VLs in 200 and 500 μL samples, but the performance of each protocol has not been compared. We evaluated the performance of both protocols for the HBV and HCV tests. Methods: Precision and linearity were verified using commercial panels. Probit analyses were used to determine limits of detection (LoDs). The results obtained with 336 samples were compared using the 200 and 500 μL protocols. Data from 6,737 retrospective HBV and 768 HCV samples were compared to estimate the effects of the different LoDs on the diagnostic results of the protocols. Correlations between protocols were tested with Spearman's rank correlation coefficients (rho). Results: The precision and linearity of both protocols were verified. The LoDs for the 200 and 500 μL protocols were 6.5 and 2.7 IU/mL for HBV and 29.7 and 8.2 IU/mL for HCV, respectively. The agreement between the protocols ranged from 0.8 to 1.0. The results obtained with the HBV and HCV tests showed a strong correlation (rho=0.994). Only 0.4% of HBV and 0.4% of HCV test results were affected by the LoDs of the 200 μL protocol. Conclusions: The Cobas 5800 200 and 500 μL protocols for the HBV DNA and HCV RNA tests demonstrated excellent performance. These findings establish the 200 μL protocol as a new option for low-volume samples, especially for pediatric and difficult-to-bleed patients. [ABSTRACT FROM AUTHOR]

Introduction: Tularemia, caused by the bacterium Francisella tularensis, poses health risks to humans and can spread through a variety of routes. It has also been classified as a Tier 1 Select agent by the CDC, highlighting its potential as a bioterrorism agent. Moreover, it is difficult to diagnose in a timely fashion, owing to the non-specific nature of tularemia infections. Rapid, sensitive, and accurate detection methods are required to reduce mortality rates. We aimed to develop antibodies directed against the outer membrane protein A of F. tularensis (FopA) for rapid and accurate diagnosis of tularemia. Methods: We used a baculovirus insect cell expression vector system to produce the FopA antigen and generate anti-FopA antibodies through immunization of BALB/c mice. We then employed hybridoma and phage display technologies to screen for antibodies that could recognize unique epitopes on FopA. Result: Two monoclonal antibodies, 6B12 and 3C1, identified through phage display screening specifically bound to recombinant FopA in a dose-dependent manner. The binding affinity of the anti-FopA 6B12 and 3C1 antibodies was observed to have an equilibrium dissociation constant of 1.76 x 10-10 M and 1.32 x 10-9 M, respectively. These antibodies were used to develop a sandwich ELISA system for the diagnosis of tularemia. This assay was found to be highly specific and sensitive, with detection limits ranging from0.062 ng/mL in PBS to 0.064 ng/mL in skim milk matrices. Discussion: Our findings demonstrate the feasibility of a novel diagnostic approach for detecting F. tularensis based on targeting FopA, as opposed to existing tests that target the bacterial lipopolysaccharide. [ABSTRACT FROM AUTHOR]

This paper evaluates the use of Factor Analysis (FA) in English education research in Korea and suggests improvements in methodology. A detailed coding protocol was used to review 179 FA cases from 12 major English education journals (2014-2023). The review identified several key issues, including small sample sizes and lenient criteria for sample size selection, insufficient reporting on data appropriateness and normality, confusion between principal component analysis and FA, overreliance on the Eigenvalue > 1 criterion for determining the number of factors, inappropriate factor rotation methods, inconsistency between factor rotation and extraction methods, inadequate reporting on factor loadings and cross loadings criteria, and excessive reliance on SPSS as a statistical tool for FA. This study provides specific guidelines for applying FA appropriately and reporting results accurately. [ABSTRACT FROM AUTHOR]

Background: Chronic myeloid leukemia (CML), a myeloproliferative neoplasm defined by the BCR::ABL1 fusion gene arising from the Philadelphia chromosome (Ph) translocation t(9:22)(q34;q11), exhibits diverse clinical courses often influenced by additional chromosomal aberrations (ACAs). This report presents a case of CML harboring a novel four-way Ph translocation involving the X chromosome, offering insights into the interplay between complex karyotypes and treatment response and emphasizing the need for further research into the role of ACAs in CML management. Methods: A 42-year-old man diagnosed with CML in the accelerated phase presented a novel four-way Ph translocation involving chromosomes X, 5, 9, and 22: 46, Y,t(X;5;9;22)(q26;q15;q34;q11.2). Despite achieving a major molecular response initially with imatinib and nilotinib, BCR::ABL1 levels (international scale) increased up to 24.0%, which prompted the use of second-line nilotinib. Results: Follow-up bone marrow (BM) studies revealed clonal evolution with trisomy 8 and an unclassified ABL1 mutation (E292V), potentially contributing to resistance. Though a transient major molecular response (MMR) occurred after a switch to third-line dasatinib, this change failed to achieve a deep molecular response, and BCRABL1 levels were elevated above the MMR. Conclusions: This case highlights the challenge of ACAs impacting CML treatment response and prognosis. Limited knowledge exists on complex Ph translocations involving the X chromosome, but this report contributes data for further research. Understanding ACA effects on therapeutic response and prognosis requires a detailed study of such complex chromosomal aberrations. [ABSTRACT FROM AUTHOR]

Background: The first purpose of this study was to determine whether a measurement of the level of direct oral anticoagulants (DOACs) was possible with heparin-calibrated chromogenic anti-factor Xa activity (AXA). The second purpose of this study was to evaluate whether the antidote treatment decision level (30 or 50 ng/mL of DOAC) can be determined by unfractionated heparin (UHF)/low molecular weight heparin (LMWH)-calibrated AXA. Methods: AXA was measured by using two reagents and dedicated analyzers (Sysmex CS-5100 analyzer and STA R Max3). Four types of calibrators were used: 1) Stago DOAC (rivaroxaban, edoxaban, and apixaban)-specific calibrator, 2) Stago LMWH calibrator, 3) Sysmex UHF calibrator, and 4) Sysmex LMWH calibrator. Regression analysis was used between assays. Receiver operating characteristic (ROC) curves were performed, and the concordance rate was calculated. Results: The correlation coefficients were in the range of 0.75 - 0.91 for rivaroxaban and 0.81 - 0.94 for apixaban. The correlation coefficient between edoxaban-calibrated AXA and Sysmex LMWH/Sysmex UHF calibrator-calibrated AXA was low (r = 0.47). Overall correlation between DOAC-calibrated AXA and Stago LMWH-calibrated AXA was linear, at only low concentration in all three DOACs. The concordance rate (89.3 - 100%) is good for determining the antidote management level by UFH/LMWH-calibrated AXA, compared with those of DOAC-calibrated AXA in rivaroxaban and apixaban. The concordance rate ranged from 63% to 67% between Sysmex UFH/LMWH-calibrated AXA and edoxaban-calibrated AXA. Conclusions: The findings of our study suggest limitations in calculating accurate concentrations, when using UFH/LMWH-calibrated AXA to measure DOAC. This study demonstrates that UFH/LMWH-calibrated AXA may be useful in determining the presence of DOACs at the cutoff level for the antidote treatment in rivarovaban and apixaban. However, in edoxaban, UFH/LMWH-calibrated AXA could not accurately measure the presence of DOACs at the cutoff for antidote treatment. [ABSTRACT FROM AUTHOR]