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BACKGROUND Thickening of Achilles tendon (≥9 mm on radiography) is one of the diagnostic criteria for familial hypercholesterolemia (FH). Since FH is associated with premature coronary artery disease (CAD) including acute coronary syndrome (ACS), measurement of Achilles tendon thickness (ATT) is important for early diagnosis of FH. However, clinical significance of mild thickening of Achilles tendon in non-FH patients with CAD is unclear. The present study investigated the association of ATT with coronary lesion severity in early-onset ACS without clinically diagnosed FH. METHODS From outpatients who had a history of ACS under 60 years old, 76 clinically non-FH subjects (71 men and 5 women; mean age at the onset of ACS, 50.5 years) with maximum ATT of

A highly intelligent visual guidance navigation system that can autonomously identify target space debris and realize a controlled rendezvous maneuver is required to mitigate space debris. In this ...

The blood levels of atrial and brain natriuretic peptides (ANP and BNP) are both increased markedly in hemodialysis patients, but the kinetics of the two are not always parallel. The present study investigated the association of changes in ANP and BNP levels before and after dialysis with changes in cardiac function in hemodialysis patients. A total of 57 patients (mean age 64 years, 47 males and 10 females) on maintenance hemodialysis with sinus rhythm were enrolled. Blood samples were taken at the beginning and end of dialysis, and plasma levels of ANP and BNP were measured. Changes in cardiac function during dialysis were examined by echocardiography performed just before and after dialysis. Both plasma ANP and BNP concentrations decreased significantly after hemodialysis, but the rate of decrease in BNP [mean ± SD, 555 ± 503 to 519 ± 477 pg/mL (- 6.4%), P = 0.011] was much smaller than that in ANP [233 ± 123 to 132 ± 83 pg/mL (- 43.4%), P 0.001]. As for the relation to the changes in echocardiographic parameters before and after dialysis, the decrease in inferior vena cava diameter had a close correlation with the decrease in ANP (r = 0.528, P 0.001), but not BNP. In contrast, the decrease in left ventricular end-diastolic volume index was correlated only with the decrease in BNP (r = 0.297, P = 0.035). The peak velocity ratio of early diastolic to atrial filling decreased with preload reduction by dialysis, and its decrease was more strongly correlated with the decrease in BNP (r = 0.407, P = 0.002) than that in ANP (r = 0.273, P = 0.040). These results demonstrated that in hemodialysis patients, the decrease in plasma ANP by a single dialysis was essentially caused by blood volume reduction, while BNP decrease was mainly induced by the reduction of left ventricular overload. Our findings indicate that the kinetics of both peptides during dialysis are regulated by different cardiac and hemodynamic factors.

Cholesterol crystals (CCs) are frequently found in high-risk plaques, such as thin-capped fibroatheromas. The purpose of this study was to investigate the associations of CCs, plaque morphologies, and post-stent optical frequency domain imaging (OFDI) findings with periprocedural cardiac troponin (cTn) elevation in patients treated with percutaneous coronary intervention (PCI). This study consists of 119 patients with stable coronary artery disease (CAD) with normal cTn levels who underwent OFDI-guided PCI. Periprocedural cTn elevation was defined as an elevation of cTn ≥ × 5 times the upper reference limit after PCI. Pre- and post-stent OFDI findings, including fibrous cap thickness (FCT), presence of CCs, and parameters for lipid and calcification were analyzed. A total of 37 (31%) patients were classified into the periprocedural cTn elevation group. Compared with lesions without CCs, lesions exhibiting CCs had thinner FCT, larger lipid arc, and longer lipid length, and were more likely to have irregular protrusion and in-stent thrombus (all p

Protective effects of tolvaptan against worsening renal function in acute heart failure have been shown. However, long-term effects of its agent on renal function remain to be elucidated. The present study investigated retrospectively whether long-term treatment with tolvaptan exerts renoprotective effects in patients with chronic heart failure, by comparing serial changes in estimated glomerular filtration rate (eGFR) for years before and after tolvaptan administration. From 63 outpatients with chronic heart failure taking diuretics including tolvaptan, 34 patients whose eGFR levels were continuously measured for more than 6 months both before and after administration of tolvaptan (average dose, 7.8 mg/day at the end of the follow-up period) were selected as eligible for the present analyses. All eGFR values were separately plotted before and after the initiation of treatment with tolvaptan (except hospitalization periods) along the time course axis and the slope of the linear regression curve was calculated as an annual change in eGFR. The mean follow-up periods before and after tolvaptan administration were 1197 and 784 days (3.3 and 2.1 years), respectively. Changing rates of eGFR per year were significantly ameliorated after treatment with tolvaptan (mean ± SD, − 8.02 ± 9.35 to − 1.62 ± 5.09 mL/min/1.73m2 /year, P = 0.001). In echocardiographic parameters, inferior vena cava (IVC) diameter significantly decreased after tolvaptan administration, and the decrease in IVC diameter was correlated with the improvement of eGFR decline slope after administration of tolvaptan (P = 0.0075). This longitudinal observational study indicated that long-term treatment with tolvaptan ameliorated annual decline in eGFR in outpatients with chronic heart failure. Our findings suggest that tolvaptan has a protective effect against chronically worsening renal function in heart failure patients.

Sensitive cardiac troponin I (cTnI) predicts all-cause and cardiovascular mortality in various clinical settings. However, its clinical significance in hemodialysis (HD) patients with preserved left ventricular ejection fraction (LVEF) has not been fully elucidated. This study investigated the association of cTnI with LV morphology and function, and its long-term outcome in HD patients with preserved LVEF. This prospective study consists of 96 HD patients with preserved LVEF (69 ± 8 years and 63% male) who underwent two-dimensional echocardiographic examination and biomarker tests including cTnI, brain natriuretic peptide, and high-sensitive C-reactive protein. The primary endpoint was all-cause death and secondary endpoint was cardiovascular death. Factors independently associated with cTnI were systolic blood pressure (β = - 0.239, p = 0.011), heart rate (β = 0.216, p = 0.021), LV mass index (β = 0.231, p = 0.020), and E to e' ratio (β = 0.237, p = 0.016). During a mean follow-up of 3.6 years, primary and secondary endpoints were observed in 23 (24%) and 18 (19%) patients, respectively. In the multivariate Cox proportional hazard analysis, the upper cTnI tertile has significantly increased risk of all-cause mortality [hazard ratio (HR), 2.69; 95% confidence interval (CI), 1.139-6.386; p = 0.024] and that of cardiovascular death (HR, 4.56; 95% CI 2.021-16.968; p = 0.006) independent of echocardiographic measures and other serum biomarkers. In HD patients with preserved LVEF, serum cTnI levels were significantly associated with diastolic function and risk of mortality independent of echocardiographic variables and other biomarkers.

There are few reports about the incidence and predictors of silent cerebral thromboembolic lesions (SCLs) after atrial fibrillation (AF) ablation in patients treated with direct oral anticoagulants (DOACs). The purpose of this study is to evaluate the incidence and predictors of SCLs after AF ablation with cerebral magnetic resonance imaging (C-MRI) in patients treated with DOACs. We enrolled 117 consecutive patients who underwent first AF ablation and received DOACs, including apixaban, dabigatran, edoxaban, and rivaroxaban. DOACs were discontinued after administration 24 h before the procedure, and restarted 6 h after the procedure. During the procedure, activated clotting time (ACT) was measured every 15 min, and intravenous heparin infusion was performed to maintain ACT at 300–350 s. All patients underwent C-MRI the day after the procedure. SCLs were detected in 28 patients (24%) after AF ablation. Age, female sex, the presence of persistent AF, left atrial volume, procedure time, radiofrequency energy, electrical cardioversion, and mean ACT showed no correlations with the incidence of SCLs. Multivariate analysis revealed independent predictors of SCLs were CHA2DS2VASc scores ≥3, left atrial appendage (LAA) emptying velocity ≤39 cm/s, and minimum ACT ≤260 s. Patients with both CHA2DS2VASc scores ≥3 and LAA flow velocity ≤39 cm/s had the highest incidence of SCLs 15 of 26 patients (58%). In patients treated with DOACs, CHA2DS2VASc score ≥3, minimum ACT ≤260 s, and LAA emptying velocity ≤39 cm/s were independent risk factors for the SCLs after AF ablation.

Background Although ankle‐brachial index (ABI) and brachial‐ankle pulse wave velocity (baPWV) are significant predictors of major adverse cardiovascular event (MACE), their prognostic value in association with biomarkers has not been fully evaluated in patients with end‐stage kidney disease (ESKD). Hypothesis We hypothesized that ABI/baPWV would provide better prognostic value independent of biomarkers in ESKD patients. Methods This study included 104 ESKD patients treated with maintenance hemodialysis who underwent ABI and baPWV examinations and laboratory tests, including brain‐natriuretic peptide, high‐sensitive cardiac troponin T (hs‐cTnT), and high‐sensitive C‐reactive protein (hs‐CRP). MACE was defined as a composite event of all‐cause death, acute coronary syndrome, and stroke. Results During a mean follow‐up of 3.6 ± 1.7 years, a total of 51 MACE were observed. The independent factors associated with MACE were age >75 years (adjusted hazard ratio [HR], 2.15; P

This paper poses the following question: How precisely must an Earth orbiter’s dynamics be mapped to accurately capture the statistical evolution of its uncertainty? This question is addressed by using a simplified dynamical system that replaces the short-period variations with constants. The systems are defined and applied to the propagation of uncertainty for a non-Keplerian orbit. The simplified dynamical system is defined with two different types of approximate solutions: one is based on the Brouwer–Lyddane theory, and another is based on Lagrange planetary equations. The simplified dynamical system allows exploration of the relationship between dynamical model precision and uncertainty propagation accuracy, as well gained insight into effects due to individual variations: that is, secular, short, and long periods. Accuracy of propagation of uncertainty with the simplified dynamical system is verified with statistical methods for dynamical models including perturbations of J2 and third-body gravity. I...

In this study, we propose an light-emitting diode (LED) illumination system that automatically estimates human comfort by capturing and analyzing brainwaves in real time and changes the brightness and color of an LED lamp accordingly to improve comfort. Taking system feasibility into account, we applied a single-channel electroencephalogram (EEG) sensor to measure brainwaves. Human comfort is estimated using the Index of Brain Resting State (IBRS), which is calculated by analyzing each frequency element of measured brainwaves. The luminosity of red, green, and blue LEDs is variously adjusted by the system to find a calming color for the person. The most calming color is estimated using the average and standard deviation of the IBRS calculated from the measured brainwaves.

Given a short-arc optical observation with estimated angle rates, the admissible region is a compact region in the range/range-rate space defined such that all likely and relevant orbits are contained within it. An alternative boundary value problem formulation has recently been proposed where range/range hypotheses are generated with two angle measurements from two tracks as input. In this paper, angle-rate information is reintroduced as a means to eliminate hypotheses by bounding their constants of motion before a more computationally costly Lambert solver or differential correction algorithm is run.

Space-based optical sensors for space situational awareness allow for tracking of objects that are smaller than currently capable with ground-based systems with less influence of atmospheric phenomena. Multiple measurements must be combined in order to obtain a full state description, but their association is uncertain a priori. In this paper, the direct Bayesian admissible region method is applied to space-based observations. Simulation results for both a low-Earth (LEO) and geosynchronous orbit (GEO) observer are shown. For the former, the proposed method successfully associates 101 observations of 8 Earth-orbiting objects taken over the span of 48 h. For the latter, lack of relative motion is identified as a key difficulty in the association process. This problem can be remediated by improved observation strategies.

One topic of recent interest in the field of space situational awareness is the accurate and consistent representation of an observed object’s uncertainty under nonlinear dynamics. This paper presents amethod of analytical nonlinear propagation of uncertainty under two-bodydynamics. In particular, the probability density function over state space and itsmean and covariancematrix are expressed analytically for all time via a special solution of the Fokker-Planck equations for deterministic Hamiltonian systems. The state transition tensor concept is used to express the solution flow of the dynamics. Some numerical examples, where a second-order state transition tensor is found to sufficiently capture the nonlinear effects, are also discussed.

For optical observations of Earth-orbiting objects, multiple observationsmust be combined to determine the orbit of the observed object.Whether two arbitrary tracks are of the same object, however, is generally unknown a priori, and solving this problem with traditional approaches requires iterative procedures that do not guarantee convergence. This paper proposes a technique of correlating multiple optical observations using highly constrained probability distributions in Poincare orbit element space. These distributions are divided into subregions, each of which are mapped linearly, to reduce computational burden, but without significantly losing accuracy. A proof-ofconcept implementation, in which simulated observations were processed, performed well. The technique proposed serves as a solution technique for initial orbit determination given two precise optical observation tracks.

Introduction: Contrast-induced acute kidney injury (CI-AKI) after percutaneous coronary intervention (PCI) is associated with adverse short- and long-term cardiovascular outcomes in patients with acute coronary syndrome (ACS). However, the association between the reduction in glomerular filtration rate (GFR) at baseline, CI-AKI, and their prognostic significance on cardiovascular outcomes has not been established. Hypothesis: We hypothesized that the decreased GFR on admission would be associated with cardiovascular outcomes in patients with ACS independent of CI-AKI. Methods: This study consists of consecutive 283 ACS patients (67±12 years old, 207 men) underwent primary-PCI. Decreased admission GFR was defined as less than 60 ml/min per 1.73m2. CI-AKI was defined as an increase of serum creatinine more than 25% within 72 hours after PCI. The primary endpoint was the occurrence of major adverse cardiovascular events (MACE) defined as cardiovascular death and non-fatal myocardial infarction. Results: Of the 283 ACS patients, 59 (21%) had CI-AKI. During median follow-up of 2-year, MACE was occurred in 36 (12%, 5.3% per year) patients. Multivariate Cox proportional hazard analysis demonstrated that higher age (hazard ratio [HR], 1.06, 95% confidence interval [CI], 1.02-1.11; p=0.002), decreased admission GFR (HR, 3.3, 95% CI; 1.45-8.02; p=0.004), and CI-AKI (HR, 2.5, CI, 1.10-5.65; p=0.03) were associated with MACE. Kaplan-Meier analysis demonstrated that patients with decreased admission GFR and CI-AKI presented worse outcomes compared with those without decreased admission GFR and CI-AKI (P Conclusions: Decreased admission GFR and CI-AKI were independent robust predictors of future MACE in ACS patients underwent primary-PCI.

Situational awareness of Earth-orbiting particles is important for human extraterrestrial activities. Given an optical observation, an admissible region can be defined over the topocentric range/range-rate space, with each point representing a possible orbit for the object. However, based on our understanding of Earth orbiting objects, we expect that certain orbits in that distribution, such as circular or zero-inclination orbits, would be more likely than others. In this research, we present an analytical approach for describing the existence of such special orbits for a given observation pass, and investigate topological features of the range/range-rate space by means of singularities in orbital elements.

The accurate assessment of cardiac function in mice is challenging because of their small heart size and rapid heart rate.We examined the usefulness of novel high-resolution echocardiography (HRE) with a 30-MHz transducer in evaluating cardiac function in 20 mice compared with conventional echocardiography (CE) with a 13-MHz transducer. The left ventricular (LV) regional wall motion (RWM), LV end-diastolic dimension, fractional shortening, anterior LV wall thickness, E/A, and myocardial performance index were assessed.RWM analysis was more feasible by HRE than by CE (P.05). Interobserver agreement in RWM analysis and correlation in LV end-diastolic dimension, fractional shortening, anterior LV wall thickness, E/A, and myocardial performance index were all better with HRE than CE.HRE is superior to CE in assessing LV function in mice. HRE is potentially a useful method for accurate assessment of cardiac function in various mice models.

OBJECTIVES We sought to evaluate the effect of acute hyperglycemia on coronary microcirculation by noninvasive measurement of coronary flow velocity reserve (CFVR) using transthoracic Doppler echocardiography (TTDE). RESEARCH DESIGN AND METHODS Measurements of CFVR using TTDE and levels of plasma glucose and serum insulin and lipids were determined before and 1 hour after loading with oral glucose (75-g glucose) in 10 young healthy males (mean age, 30 +/- 2 years) or an artificial sweetener in five of the 10 subjects without coronary risk factors. RESULTS In all subjects, the levels of plasma glucose and serum insulin significantly increased after glucose loading compared with baseline (5.1 +/- 0.6 vs 7.6 +/- 1.2 mM/l, 6 +/- 3 vs 49 +/- 13 microU/ml, respectively; P < 0.0001). CFVR was significantly decreased 1 hour after acute oral glucose loading (4.4 +/- 0.7-3.8 +/- 0.7, respectively; P < 0.01). There was no significant change in CFVR after loading with an artificial sweetener (4.4 +/- 0.6-4.4 +/- 0.5 cm/sec). CONCLUSIONS TTDE revealed that acute hyperglycemia induced by oral glucose loading suppresses CFVR in healthy young male subjects. This result suggests that acute hyperglycemia may have adverse effects on coronary microcirculation.

本研究では，リーダーの影響力の「強さ」と「範囲」に及ぼす集団プロトタイプ性の効果について検討した。仮説は次の通りである。（1）集団同一視の高い参加者群において，集団プロトタイプ性の高いリーダーの方が低いリーダーより承認されるであろう。（2）高プロトタイプ・リーダーの影響力が，ある外集団との比較による脱個人化された社会的魅力に由来することを考慮すると，高プロトタイプ・リーダーが低プロトタイプ・リーダーの影響力を上回るのは，その外集団と関連する課題に従事する場合だけであろう。ただし，外集団関連課題における高プロトタイプ・リーダーの影響力は，たとえフォロワーの意向に沿わない指示であっても応諾させるほど強いであろう。実験参加者124名に他集団との対立状況を描いたシナリオを呈示し，質問紙への回答を求めた。その結果，直接的な応諾度指標ではなく，間接的な応諾度指標について，仮説は概ね支持された。本研究の結果の一部は，社会的アイデンティティ理論や自己カテゴリー化理論の視座からの予測とは必ずしも一致しないものであった。最後に，本研究の知見の解釈，本研究の限界，および今後の課題について考察した。

This study examined the effect of azithromycin therapy on the coronary microcirculation using measurement of coronary flow velocity reserve (CFVR) by transthoracic Doppler echocardiography in 35 patients with coronary artery disease. CFVR increased significantly after azithromycin therapy (3.0 +/- 0.7 vs 3.5 +/- 0.7, p0.001). The changes in CFVR were negatively correlated with changes in high-sensitivity C-reactive protein levels in patients receiving azithromycin.

The direct Bayesian admissible region approach is an a priori state free measurement association and initial orbit determination technique for optical tracks. In this paper, we test a hybrid approach that appends a least squares estimator to the direct Bayesian method on measurements taken at the Zimmerwald Observatory of the Astronomical Institute at the University of Bern. Over half of the association pairs agreed with conventional geometric track correlation and least squares techniques. The remaining pairs cast light on the fundamental limits of conducting tracklet association based solely on dynamical and geometrical information.

A high-fidelity simulation is developed to test the theory that relative range and range-rate measurements between a satellite in a geosynchronous orbit and a satellite in orbit about the Earth-Moon L1 point may be used to improve the navigation accuracy of both satellites, compared with ground-only tracking. Recent research has determined that satellite-to-satellite range measurements between these two orbits are su cient to perform absolute state estimation as well as relative state estimation of both satellites - a technology known as LiAISON (Linked Autonomous Interplanetary Satellite Orbit Navigation). This study quanties the improvement in accuracy when LiAISON is used to supplement ground tracking of one or both satellites in a very realistic simulation. Orbit determination techniques show that the inclusion of LiAISON measurements with ground tracking observations can greatly improve absolute position and velocity estimates for both satellites in geosynchronous orbit and about the Earth-Moon L1 point.

Linked Autonomous Interplanetary Satellite Orbit Navigation (LiAISON) is a new technique that takes advantage of the asymmetrical gravity field present in a three-body system in order to perform absolute tracking of satellites using only relative satellite-to-satellite observations. Previous studies have demonstrated LiAISON's practical applications for lunar missions, including a satellite in a halo orbit about either the Earth-Moon L1 or L2 point. This paper studies the viability of applying LiAISON measurements between a lunar halo orbiter and a satellite in a geosynchronous orbit. Simulations demonstrate that the absolute positions and velocities of both satellites are observable using only relative measurements with an achieved uncertainty on the order of observation noise.

Optical observations of Earth-orbiting particles are singular in that multiple observations are required to determine the state of the object. It is generally uncertain, however, whether two arbitrary singular observations are of the same object, and solving this problem can be computationally intensive. In this paper, we propose a technique of correlating multiple singular observations and providing an initial estimate of the observed object's state by means of probability distributions in state space, provided the distributions have high-codimension.

Background It has been suggested that myocardial systolic impairment may not be accurately detected by the evaluation of endocardial excursion alone. The aim of this study was to test the hypothesis that changes in left ventricular (LV) subendocardial and subepicardial strain are sensitive markers of severity of aortic stenosis (AS) and LV function in patients with AS. Methods Transthoracic echocardiography was performed in 73 consecutive patients with AS who had preserved systolic function and in 20 controls. Longitudinal strain, subendocardial radial strain, subepicardial radial strain, and transmural radial strain were measured using LV apical and short-axis images. Results The 73 patients enrolled in this study were classified according to AS severity: mild ( n = 10), moderate ( n = 15), or severe ( n = 48). Although transmural and subepicardial radial strain showed similar values in all groups, subendocardial radial strain and longitudinal strain could differentiate mild or moderate AS from severe AS. Only the ratio of subendocardial to subepicardial radial strain (the bilayer ratio) decreased significantly as the severity of AS increased. Bilayer ratio showed weak correlations with LV ejection fraction ( r = 0.37) and E/E′ ratio ( r = −0.33) and moderate correlations with LV mass ( r = −0.55) and aortic valve area ( r = 0.71). Moreover, bilayer ratio was independently associated with AS severity ( P = .001). In 21 patients who underwent aortic valve replacement, subendocardial radial strain and bilayer ratio increased 7 days after surgery, whereas other echocardiographic parameters of LV function showed no improvement. Conclusions Bilayer ratio can reliably differentiate patients with varying degrees of AS severity and is a sensitive marker of LV function. These findings suggest that the evaluation of subendocardial and subepicardial radial strain might be a novel method for assessing LV mechanics in patients with AS.