Dual Sequence Research Articles

Lotus (Nelumbo nucifera G.) seed starch: Understanding the impact of physical modification sequence (ultrasonication and HMT) on properties and in vitro digestibility

Native lotus (Nelumbo nucifera G.) seed starch (LSS) was single- and dual-modified by heat-moisture treatment (HMT), ultrasonication (US), HMT followed by the US (HMT-US), and the US followed by HMT (US-HMT). The modified lotus seed starch (LSS) was evaluated for its physicochemical, pasting, thermal, and rheological properties and in vitro digestibility. All treatments decreased the swelling power (10.52–14.0 g/g), solubility (12.20–15.95 %), and amylose content (23.71–25.67 %) except for ultrasonication (17.67 g/g, 17.90 %, 29.09 %, respectively) when compared with native LSS (15.05 g/g, 16.12 %, 27.12 %, respectively). According to the rheological study, G′ (1665–4004 Pa) was greater than G″ (119–308 Pa) for all LSS gel samples demonstrating their elastic character. Moreover, gelatinization enthalpy (17.56–16.05 J/g) increased in all treatments compared to native LSS (15.38 J/g). Ultrasonication treatment improved the thermal stability of LSS. The digestibility results showed that dual modification using HMT and US significantly enhanced resistant starch (RS) and reduced slowly digestible starch (SDS) in LSS. Cracks were observed on the surface of the modified LSS granules. Peak viscosity decreased in all modified starches except for ultrasonication, suggesting their resistance to shear-thinning during cooking, making them ideal weaning food components. The results obtained after different modifications in this study could be a useful ready reference to select appropriate modification treatments to produce modified LSS with desired properties depending on their end-use.

Radiomics combined with clinical and MRI features may provide preoperative evaluation of suboptimal debulking surgery for serous ovarian carcinoma.

To develop and validate a model for predicting suboptimal debulking surgery (SDS) of serous ovarian carcinoma (SOC) using radiomics method, clinical and MRI features. 228 patients eligible from institution A (randomly divided into the training and internal validation cohorts) and 45 patients from institution B (external validation cohort) were collected and retrospectively analyzed. All patients underwent abdominal pelvic enhanced MRI scan, including T2-weighted imaging fat-suppressed fast spin-echo (T2FSE), T1-weighteddual-echomagnetic resonanceimaging (T1DEI), diffusion weighted imaging (DWI), and T1 with contrast enhancement (T1CE). We extracted, selected and eliminated highly correlated radiomic features for each sequence. Then, Radiomic models were made by each single sequence, dual-sequence (T1CE + T2FSE), and all-sequence, respectively. Univariate and multivariate analyses were performed to screen the clinical and MRI independent predictors. The radiomic model with the highest area under the curve (AUC) was used to combine the independent predictors as a combined model. The optimal radiomic model was based on dual sequences (T2FSE + T1CE) among the five radiomic models (AUC = 0.720, P < 0.05). Serum carbohydrate antigen 125, the relationship between sigmoid colon/rectum and ovarian mass or mass implanted in Douglas' pouch, diaphragm nodules, and peritoneum/mesentery nodules were considered independent predictors. The AUC of the radiomic-clinical-radiological model was higher than either the optimal radiomic model or the clinical-radiological model in the training cohort (AUC = 0.908 vs. 0.720/0.854). The radiomic-clinical-radiological model has an overall algorithm reproducibility and may help create individualized treatment programs and improve the prognosis of patients with SOC.

Characterization of the dual regulation by a c-di-GMP riboswitch Bc1 with a long expression platform from Bacillus thuringiensis.

A riboswitch generally regulates the expression of its downstream genes through conformational change in its expression platform (EP) upon ligand binding. The cyclic diguanosine monophosphate (c-di-GMP) class I riboswitch Bc1 is widespread and conserved among Bacillus cereus group species. In this study, we revealed that Bc1 has a long EP with two typical ρ-independent terminator sequences 28 bp apart. The upstream terminator T1 is dominant in vitro, while downstream terminator T2 is more efficient in vivo. Through mutation analysis, we elucidated that Bc1 exerts a rare and incoherent "transcription-translation" dual regulation with T2 playing a crucial role. However, we found that Bc1 did not respond to c-di-GMP under in vitro transcription conditions, and the expressions of downstream genes did not change with fluctuation in intracellular c-di-GMP concentration. To explore this puzzle, we conducted SHAPE-MaP and confirmed the interaction of Bc1 with c-di-GMP. This shows that as c-di-GMP concentration increases, T1 unfolds but T2 remains almost intact and functional. The presence of T2 masks the effect of T1 unwinding, resulting in no response of Bc1 to c-di-GMP. The high Shannon entropy values of EP region imply the potential alternative structures of Bc1. We also found that zinc uptake regulator can specifically bind to the dual terminator coding sequence and slightly trigger the response of Bc1 to c-di-GMP. This work will shed light on the dual-regulation riboswitch and enrich our understanding of the RNA world.IMPORTANCEIn nature, riboswitches are involved in a variety of metabolic regulation, most of which preferentially regulate transcription termination or translation initiation of downstream genes in specific ways. Alternatively, the same or different riboswitches can exist in tandem to enhance regulatory effects or respond to multiple ligands. However, many putative conserved riboswitches have not yet been experimentally validated. Here, we found that the c-di-GMP riboswitch Bc1 with a long EP could form a dual terminator and exhibit non-canonical and incoherent "transcription-translation" dual regulation. Besides, zinc uptake regulator specifically bound to the coding sequence of the Bc1 EP and slightly mediated the action of Bc1. The application of SHAPE-MaP to the dual regulation mechanism of Bc1 may establish the foundation for future studies of such complex untranslated regions in other bacterial genomes.

Pulmonary transit time is a predictor of outcomes in heart failure: a cardiovascular magnetic resonance first-pass perfusion study

BackgroundPulmonary transit time (PTT) can be measured automatically from arterial input function (AIF) images of dual sequence first-pass perfusion imaging. PTT has been validated against invasive cardiac catheterisation correlating with both cardiac output and left ventricular filling pressure (both important prognostic markers in heart failure). We hypothesized that prolonged PTT is associated with clinical outcomes in patients with heart failure.MethodsWe recruited outpatients with a recent diagnosis of non-ischaemic heart failure with left ventricular ejection fraction (LVEF) < 50% on referral echocardiogram. Patients were followed up by a review of medical records for major adverse cardiovascular events (MACE) defined as all-cause mortality, heart failure hospitalization, ventricular arrhythmia, stroke or myocardial infarction. PTT was measured automatically from low-resolution AIF dynamic series of both the LV and RV during rest perfusion imaging, and the PTT was measured as the time (in seconds) between the centroid of the left (LV) and right ventricle (RV) indicator dilution curves.ResultsPatients (N = 294) were followed-up for median 2.0 years during which 37 patients (12.6%) had at least one MACE event. On univariate Cox regression analysis there was a significant association between PTT and MACE (Hazard ratio (HR) 1.16, 95% confidence interval (CI) 1.08–1.25, P = 0.0001). There was also significant association between PTT and heart failure hospitalisation (HR 1.15, 95% CI 1.02–1.29, P = 0.02) and moderate correlation between PTT and N-terminal pro B-type natriuretic peptide (NT-proBNP, r = 0.51, P < 0.001). PTT remained predictive of MACE after adjustment for clinical and imaging factors but was no longer significant once adjusted for NT-proBNP.ConclusionsPTT measured automatically during CMR perfusion imaging in patients with recent onset non-ischaemic heart failure is predictive of MACE and in particular heart failure hospitalisation. PTT derived in this way may be a non-invasive marker of haemodynamic congestion in heart failure and future studies are required to establish if prolonged PTT identifies those who may warrant closer follow-up or medicine optimisation to reduce the risk of future adverse events.

A Mimic Fusion Algorithm for Dual Channel Video Based on Possibility Distribution Synthesis Theory

In response to the current practical fusion requirements for infrared and visible videos, which often involve collaborative fusion of difference feature information, and model cannot dynamically adjust the fusion strategy according to the difference between videos, resulting in poor fusion performance, a mimic fusion algorithm for infrared and visible videos based on the possibility distribution synthesis theory is proposed. Firstly, quantitatively describe the various difference features and their attributes of the region of interest in each frame of the dual channel video sequence, and select the main difference features corresponding to each frame. Secondly, the pearson correlation coefficient is used to measure the correlation between any two features and obtain the feature correlation matrix. Then, based on the similarity measure, the fusion effective degree distribution of each layer variables for different difference features is constructed, and the difference feature distribution is correlated and synthesized based on the possibility distribution synthesis theory. Finally, optimize the select of mimic variables to achieve mimic fusion of infrared and visible videos. The experimental results show that the proposed method achieve significant fusion results in preserving targets and details, and was significantly superior to other single fusion methods in subjective evaluation and objective analysis.

On Orlicz classes defined in terms of associated weight functions

N-functions and their growth and regularity properties are crucial in order to introduce and study Orlicz classes and Orlicz spaces. We consider N-functions which are given in terms of so-called associated weight functions. These functions are frequently appearing in the theory of ultradifferentiable function classes and in this setting additional information is available since associated weight functions are defined in terms of a given weight sequence. We express and characterize several known properties for N-functions purely in terms of weight sequences which allows to construct (counter-) examples. Moreover, we study how for abstractly given N-functions this framework becomes meaningful and finally we establish a connection between the complementary N-function and the recently introduced notion of the so-called dual sequence.

Displacement Micropump with Check Valves for Diabetes Care—The Challenge of Pumping Insulin at Negative Pressure

The displacement micropump with passive check valves is an attractive solution for precise insulin infusion in patients with type I diabetes. Unlike most insulin pumps that push insulin from a cartridge using a piston, a displacement micropump will first pull insulin from the reservoir before infusing it into the patient. This dual sequence introduces new challenges in terms of insulin stability, notably if the reservoir is not pressurized. After an introduction to displacement micropumps and a brief review of the insulin degradation mechanism, micropump design rules are discussed in light of microfluidic theory.

Self-Decoupled Dual Sequence Current Control of D-STATCOM Under Unbalanced Grid Voltage

Self-Decoupled Dual Sequence Current Control of D-STATCOM Under Unbalanced Grid Voltage

Design, optimization, and comparative analysis of wide-band polarization conversion along with dual coding sequences for RCS reduction

In this paper, a wideband polarization conversion metasurface is designed. Additionally, coding and chessboard metasurfaces are specifically tailored for radar cross-section reduction (RCS). Initially, a compact unit cell demonstrating exceptional polarization conversion performance is introduced, achieving a polarization conversion ratio (PCR) exceeding 90%\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$\\%$$\\end{document} across frequencies ranging from 7.9 to 22.7 GHz. The PCR remains effective even when oblique incidence angles of up to 30∘\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$^\\circ$$\\end{document} are utilized across this frequency band. Roger RT5880, with a thickness of 0.254 mm, serves as the substrate. An airgap is introduced between the substrate and the ground plane to enhance the polarization conversion bandwidth. This unit cell serves as the fundamental building block for subsequent metasurface configurations. To assess the scalability and effectiveness, a 36 ×\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$\ imes$$\\end{document} 36 unit array is assembled, confirming efficient polarization conversion capabilities extending to larger structures. Moreover, a 1-bit coding unit “0” and “1” are formed by the Pancharatnam-Berry phase based on the same-sized meta-atom with 90∘\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$^\\circ$$\\end{document} orientations. The robustness and practicality of the design are demonstrated by creating 12 ×\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$\ imes$$\\end{document} 12 lattices and evaluating their RCS reduction potential under two distinct scenarios: a chessboard pattern and a coding-based scheme. Notably, its results indicate substantial RCS reduction across a broad frequency spectrum (7.9 to 22.7 GHz) for both configurations. This study demonstrates the wide-ranging applicability of metasurface design, making it a valuable contribution to the fields of microwave engineering, polarization control, and radar stealth technology. Owing to its simplicity, bandwidth, and versatility, this approach offers innovative solutions for diverse real-world applications.

Dual Inversion Recovery Magnetic Resonance Imaging's Diagnostic Value for Estimating the Overall Load of Multiple Sclerosis Lesions and its Anatomical Distribution

B Background: In young adults, multiple sclerosis is a prevalent chronic inflammatory demyelinating condition. It is characterized by white matter affection, but many individuals also have significant gray matter involvement. A double inversion recovery pulse pattern was recently proposed to improve the detectability of multiple sclerosis lesions. Objectives: To evaluate the diagnostic value of double inversion recovery sequence in the detection of cortical and white matter multiple sclerosis plaques in different brain anatomical locations. Subjects and methods: A total of 37 patients with an established diagnosis of multiple sclerosis were included in this cross-sectional study. Brain MRI was done using double inversion recovery, T2 and FLAIR sequences. The number of lesions was counted and compared in the three sequences. Results: Dual Inversion Recovery sequence was highly significant and superior to both T2 and FLAIR sequences (P &lt; 0.001) in depicting the lesions regardless of anatomical distribution. Dual Inversion Recovery was significantly superior to T2 (P =&lt;0.001) and FLAIR (P =&lt;0.001) in detecting lesions in cortical and juxtacortical. However, Dual Inversion Recovery shows less periventricular and deep white matter lesions in comparison to T2 and FLAIR sequences. Conclusion: The Dual Inversion Recovery sequence detected more multiple sclerosis lesions in cortical, subcortical and infratentorial than the traditional T2W and FLAIR sequences. It also demonstrated greater delineation between the white matter, grey matter, and multiple sclerosis lesions, which became more easily visualized.

The Minimum Admissible Detuning Efficiency of MRI Receive-Only Surface Coils.

The minimum admissible detuning efficiency (DE) of a receive coil is an essential parameter for coil designers. A receive coil with inefficient detuning leads to inhomogeneous B1 during excitation. Previously proposed criteria for quantifying the DE rely on indirect measurements and are difficult to implement. To present an alternative method to quantify the DE of receive-only surface coils. Theoretical study supported by simulations and phantom experiments. Uniform spherical (100 mm diameter) and cylindrical (66 mm diameter) phantoms. Dual repetition time B1 mapping sequence at 1.5T, and Bloch-Siegert shift B1 mapping sequence at 3.0T. One non-planar (80 × 43 mm2) and two planar (40 and 57 mm diameter) surface coils were built. Theoretical analysis was performed to determine the minimum DE required to avoid B1 distortions. Experimental B1 maps were acquired for the non-planar and planar surface coils at both 1.5T and 3.0T and visually compared with simulated B1 maps to assess the validity of the theoretical analysis. None. Based on the theoretical analysis, the proposed minimum admissible DE, defined as DEthr = 20 Log (Q) + 13 dB, depended only on the quality factor (Q) of the coil and was independent of coil area and field strength. Simulations and phantom experiments showed that when the DE was higher than this minimum threshold level, the B1 field generated by the transmission coil was not modified by the receive coil. The proposed criterion for assessing the DE is simple to measure, and does not depend on the area of the coil or on the magnetic field strength, up to 3T. Experimental and simulated B1 maps confirmed that detuning efficiencies above the theoretically derived minimal admissible DE resulted in a non-distorted B1 field. 2 TECHNICAL EFFICACY: Stage 1.

Comparison of dual-bolus versus dual-sequence techniques for determining myocardial blood flow and myocardial perfusion reserve by cardiac magnetic resonance stress perfusion: From the Automated Quantitative analysis of myocardial perfusion cardiac Magnetic Resonance Consortium

BackgroundQuantitative stress cardiac magnetic resonance (CMR) can be performed using the dual sequence (DS) technique or dual bolus (DB) method. It is unknown if DS and DB produce similar results for myocardial blood flow (MBF) and myocardial perfusion reserve (MPR). The study objective is to investigate if there are any differences between DB and DS derived MBF and MPR. MethodsRetrospective observational study with 168 patients underwent stress CMR. Dual bolus and dual sequence methods were simultaneously performed on each patient on the same day. Global and segmental stress MBF and rest MBF values were collected. ResultsUsing Bland-Altman analysis, segmental and global stress MBF values were higher in DB than DS (0.22 + 0.60ml/g/min, p<0.001 and 0.20 + 0.48ml/g/min, p=0.005 respectively) with strong correlation (r = 0.81, p < 0.001 for segmental and r = 0.82, p < 0.001 for global). In rest MBF, segmental and global DB values were higher than by DS (0.15 + 0.51ml/g/min, p<0.001 and 0.14 + 0.36ml/g/min, p=0.011 respectively) with strong correlation (r = 0.81, p < 0.001 and r = 0.77, p < 0.001). Mean difference between MPR by DB and DS was -0.02 + 0.68ml/g/min (p=0.758) for segmental values and -0.01 + 0.49ml/g/min (p=0.773) for global values. MPR values correlated strongly as well in both segmental and global, both (r = 0.74, p < 0.001) and (r = 0.75, p < 0.001) respectively. ConclusionsThere is very good correlation between DB and DS derived MBF and MPR values. However, there are significant differences between DB and DS derived global stress and rest MBF. Whilst MPR values did not show statistically significant differences between DB and DS methods.

The ADMM algorithm for audio signal recovery and performance modification with the dual Douglas-Rachford dynamical system

&lt;abstract&gt;&lt;p&gt;Practitioners employ operator splitting methods—such as alternating direction method of multipliers (ADMM) and its "dual" Douglas-Rachford method (DR)—to solve many kinds of optimization problems. We provide a gentle introduction to these algorithms, and illustrations of their duality-like relationship in the context of solving basis pursuit problems for audio signal recovery. Recently, researchers have used the dynamical systems associated with the iterates of splitting methods to motivate the development of schemes to improve performance. These developments include a class of methods that act by iteratively minimizing surrogates for a Lyapunov function for the dynamical system. An exemplar of this class is currently state-of-the-art for the feasibility problem of finding wavelets with special structure. Early experimental evidence has also suggested that, when implemented in a primal-dual (ADMM and DR) framework, this exemplar may provide improved performance for basis pursuit problems. We provide a reasonable way to compute the updates for this exemplar, and we study the application of this method to the aforementioned basis pursuit audio problems. We provide experimental results and visualizations of the dynamical system for the dual DR sequence. We observe that for highly structured problems with real data, the algorithmic behavior is noticeably different than for randomly generated problems.&lt;/p&gt;&lt;/abstract&gt;

Electrochemical aptamer sensor based on AgNPs@PDANSs and "sandwich" structure guidance for the detection of tobramycin in water samples.

In this study, an ultrasensitive detection platform for tobramycin (TOB) was developed, featuring a "sandwich" structure guided by AgNCs@PDANSs and Thi-AuNCs@ZnONSs. To address the issue of large background current peak signals in tagless sensors, Thi-AuNCs@ZnONSs composites were synthesized as signal tags. Zinc oxide nanosheets (ZnONSs) served as the loading agent, and AuNCs with the electroactive molecule Thi acted as carriers. Furthermore, AgNPs@PDANSs nanocomposites, possessing excellent electrical conductivity and large specific surface areas, were prepared as substrate materials for the modified electrodes. A "sandwich" structure strategy was also introduced to enhance the accuracy of the electrochemical aptasensor. This strategy, utilizing a dual sequence for target labeling and capture, yielded higher sensitivity and simplified the sensor construction compared to methods employing a single sequence. Under optimal conditions, the detection limit for TOB was established at 1.41 pM, with a detection range of 0.05-5000 nM. The aptasensor was effectively applied in the detection of TOB in tap and lake water, demonstrating outstanding reproducibility, selectivity, and stability. These results may serve as a reference for environmental TOB detection.

SR-DSGA: Session Recommendation for Dual Sequence Based on Graph Neural Network and Multi-Attention

SR-DSGA: Session Recommendation for Dual Sequence Based on Graph Neural Network and Multi-Attention

DSPM: Dual sequence prediction model for efficient energy management in micro-grid

Power generation and consumption predictions are fundamental for smart grid operations, addressing challenges posed by renewable energy variability and irregular consumer demand. This study introduces the Dual Sequence Predictive Model (DSPM) based on Spatiotemporal CNN (STCNN) architecture, offering a holistic solution for forecasting Electricity Generation (EG) and Electricity Consumption (EC) collectively. Leveraging STCNN, the DSPM efficiently extracts spatial and temporal information, improving prediction accuracy and processing speed. A 1D spatial attention module is added to capture crucial spatial dependencies in historical data. Incorporating shared historical weather information streamlines learning process and reduces model complexity. Extensive benchmark evaluations demonstrate the DSPM superior performance, achieving the lowest error rates compared to baseline models. The DSPM also employs the Kullback–Leibler Divergence (KLD) algorithm for power generation and consumption matching, ensuring efficient power distribution within smart and microgrids. Furthermore, the DSPM is evaluated alongside Single Sequence Prediction (SSP) models, providing a comprehensive analysis of its capabilities and comparisons with state-of-the-art models. The SSP model achieved an average RMSE reduction of 17.3% for solar EG data and 15.86% for IHEPC residential EC data, while DSPM reduced RMSE by 7.57% over PowerGrid dataset compared to baseline models.

Systematic comparison of nonviral gene delivery strategies for efficient co-expression of two transgenes in human mesenchymal stem cells

BackgroundHuman mesenchymal stem cells (hMSCs) are being researched for cell-based therapies due to a host of unique properties, however, genetic modification of hMSCs, accomplished through nonviral gene delivery, could greatly advance their therapeutic potential. Furthermore, expression of multiple transgenes in hMSCs could greatly advance their clinical significance for treatment of multifaceted diseases, as individual transgenes could be expressed that target separate pathogenic drivers of complex diseases. Expressing multiple transgenes can be accomplished by delivering multiple DNA vectors encoding for each transgene, or by delivering a single poly-cistronic vector that encodes for each transgene and accomplishes expression through either use of multiple promoters, an internal ribosome entry site (IRES), or a 2A peptide sequence. These different transgene expression strategies have been used to express multiple transgenes in various mammalian cells, however, they have not been fully evaluated in difficult-to-transfect primary cells, like hMSCs. This study systematically compared four transgene expression and delivery strategies for expression of two reporter transgenes in four donors of hMSCs from two tissue sources using lipid- and polymer-mediate transfection, as follows: (i) delivery of separate DNA vectors in separate nanoparticles; (ii) delivery of separate DNA vectors combined in the same nanoparticle; (iii) delivery of a bi-cistronic DNA vector with an IRES sequence via nanoparticles; and (iv) delivery of a bi-cistronic DNA vector with a dual 2A peptide sequence via nanoparticles.ResultsOur results indicate that expression of two transgenes in hMSCs, independent of expression or delivery strategy, is inefficient compared to expressing a single transgene. However, delivery of separate DNA vectors complexed in the same nanoparticle, or delivery of a bi-cistronic DNA vector with a dual 2A peptide sequence, significantly increased the number of hMSCs expressing both transgenes compared to other conditions tested.ConclusionSeparate DNA vectors delivered in the same nanoparticle and bi-cistronic DNA vectors with dual 2A peptide sequences are highly efficient at simultaneously expressing two transgenes in multiple donors of hMSCs from different tissue sources. The data presented in this work can guide the development of hMSC transfection systems for delivery of multiple transgenes, with the goal of producing clinically relevant, genetically modified hMSCs.

A Novel Lithium-Ion Battery Impedance Fast Measurement Method With Enhanced Excitation Signal

Online battery impedance acquisition is of increasing interest due to its valuable information for state estimation and fault diagnosis. The Pseudo Random Sequence (PRS) can significantly mitigate the required time cost, yet suffers from an insufficient Signal-to-Noise Ratio (SNR). Motivated by this, this paper proposes a novel series-connected Dual Pseudo Random Sequence (DPRS) for enhancing the signal power content in all frequency ranges, which notably improves the robustness of broadband impedance acquisition against interference. A Weighted Bilateral Impedance Filter (WBIF) is further carried out on a semi-logarithm scale to process the measurement data, which effectively compensates for the noise-induced biases and enables a nearly unbiased result. Experimental studies verify the proposed framework by comparing it with the conventional PRS method in terms of accuracy and robustness under various States of Charges (SOCs), ambient temperatures, and aging status of the batteries.

Abstract 16882: Comparison of Regadenoson and Adenosine in First Pass Quantitative Perfusion Cardiovascular Magnetic Resonance in Subjects With Suspected Coronary Microvascular Disease

Introduction: Regadenoson and adenosine are commonly used vasodilators in myocardial perfusion imaging for detection of coronary artery disease. There are no comparative studies of the vasodilator properties of two agents in subjects with suspected coronary microvascular disease (CMD). We aimed to compare the potency of two vasodilators by quantifying myocardial perfusion in subjects with suspected CMD. Methods: Subjects with angina and more than two risk factors for CMD (females, or males with diabetes, metabolic syndrome, HTN, hyperlipidemia, and smoking) who had no obstructive coronary disease by invasive coronary angiography or CT angiography were enrolled for first-pass perfusion images using dual sequence. Stress perfusion images were acquired on 1.5T or 3.0T GE Healthcare during adenosine infusion or regadenoson. Rest perfusion images were acquired either 10 minutes following the cessation of adenosine or reversal with aminophylline. Myocardial blood flow (MBF) in ml/min/g and myocardial perfusion reserve (MPR) were quantified using Fermi deconvolution. Results: A total of thirty-two subjects were recruited with a mean age of 62±11 years, 53% men, history of hypertension in 91%, diabetes in 72%, hyperlipidemia in 75%, and tobacco use in 16%. Twenty (63%) of subjects underwent adenosine, while twelve (38%) of subjects underwent regadenoson. Regadenoson produced similar stress MBF compared to adenosine (2.30 ± 0.54 vs. 2.35 ± 0.61 ml/min/g, p = 0.66). Rest MBF was higher in the regadenoson group compared to adenosine group (1.35±0.35 vs. 1.12±0.26 ml/min/g, p=0.07). MPR was non-significantly lower in regadenoson compared to adenosine 1.72±0.70 vs.1.89±0.53 ml/g/min, p=0.13). Conclusions: Based on fully quantitative perfusion using CMR, regadenoson and adenosine have similar vasodilator efficacy in subjects with risk factors for CMD. However, resting blood flows are slightly higher when regadenoson is used which may impact quantification of MPR.

Abstract 16817: Comparison of Diagnostic Performance of Quantitative Perfusion Stress Myocardial Perfusion Imaging With Cardiac Magnetic Resonance Between Different Vasodilators

Introduction: Adenosine and regadenoson are commonly used vasodilators in myocardial perfusion imaging for assessment of suspected coronary artery disease. Hypothesis: The aim of this study is to determine the difference between the different vasodilators by quantifying stress and rest myocardial perfusion using cardiovascular magnetic resonance (CMR). Methods: Subjects with known or suspected CAD from 10 centers undergoing invasive coronary angiography or CT angiography were enrolled for rest and stress first-pass perfusion images using dual sequence. First-pass stress perfusion images were acquired on 1.5T or 3.0T GE scanner during adenosine or Regadenoson. Fully quantitative perfusion values were determined using Fermi deconvolution. Significant CAD was defined by: presence of≥50% stenosis in the left main coronary artery or ≥70% in the one major vessel. Diagnostic performance of stress myocardial blood flow (MBF) and myocardial perfusion reserve (MPR) was measured using receiver operating characteristics curves. Results: A total of 89 subjects were recruited with a median age of 66 yrs, 69% men, 55% significant CAD, history of hypertension in 78%, diabetes in 48%, and hyperlipidemia in 74%. 36 subjects used adenosine, while 53 used regadenoson as the vasodilator agent. Stress MBF had a good area under the curve for adenosine vs. regadenoson [ 0.89 (0.78-1.00) vs. 0.82 (0.66-0.98), p=0.43], sensitivity (100% vs. 84%), and specificity (80% vs. 80%). MPR had a higher area under the curve for adenosine than regadenoson [0.87 (0.75-0.98) vs. 0.68 (0.52-0.84), p=0.06], sensitivity (100% vs. 61%), and specificity (68% vs. 73%). (Figure) Conclusions: Our study showed that fully quantitative perfusion using CMR, regadenoson, and adenosine have similar good diagnostic accuracy when stress MBF was used as the diagnostic parameter. However, adenosine outperformed regadenoson for the detection of significant CAD when MPR was used as the diagnostic parameter.