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Background: Fulminant myocarditis presentation (FMP) is a rare and severe presentation of myocarditis. The natural history of FMP and its clinical features associated with poor outcomes are incompletely understood because there is a lack of generalizable evidence. Methods: This multicenter retrospective cohort study included patients hospitalized with histologically proven myocarditis who underwent catecholamine or mechanical support from 235 cardiovascular training hospitals across Japan between April 2012 and March 2017. Clinical features and the prognostic predictors of death or heart transplantation within 90 days on the basis of clinical and pathologic findings were determined using the Kaplan-Meier method, log-rank test, and Cox regression analysis. Results: This study included 344 patients with histologically proven FMP (median age, 54 years; 40% female). The median follow-up was 600 days (interquartile range, 36 to 1599 days) and the cumulative risk of death or heart transplantation at 90 days was 29% (n=98). Results from multivariable Cox regression analysis showed that older age, nonsinus rhythm, low left ventricular wall motion ( Conclusions: The results from analyses of data from this multicenter registry demonstrated that patients with FMP are at a higher risk of death or heart transplantation in real-world settings. These observations inform which clinical and pathologic findings may be useful for prognostication in FMP. Registration: URL: https://www.umin.ac.jp/ctr ; Unique identifier: UMIN000039763.

The global coronavirus disease-2019 (COVID-19) pandemic is associated with reduced rate of percutaneous coronary intervention (PCI). However, there were a few data showing how emergency medical system (EMS) and management strategies for acute coronary syndrome (ACS) changed during the pandemic. We sought to clarify changes on characteristics, treatments, and in-hospital mortality of patients with ACS transported via EMS between pre- and post-pandemic. We examined consecutive 656 patients with ACS admitted to Sapporo City ACS Network Hospitals between June 2018 and November 2021. The patients were divided into pre- and post-pandemic groups. The number of ACS hospitalisations declined significantly during the pandemic (proportional reduction 66%, coefficient − 0.34, 95% CI -0.50 to -0.18, p

Purpose Phrenic nerve injury (PNI) is one of the important complications during cryoballoon (CB) ablation. Recording diaphragmatic compound motor action potentials (CMAPs) during CB ablation can predict PNI. CMAP monitoring may be inaccurate when CMAP amplitudes are low. We examined the effect of positioning an electrocardiography (ECG) electrode at the dorsal side. Methods We retrospectively analyzed the cases of 197 consecutive patients who underwent CB ablation for pulmonary vein isolation (PVI) (April 2016 to December 2018) at our institution. CMAP amplitudes were monitored using two recording methods just before cryoapplication. (a) Conventional method: right‐arm ECG electrode positioned 5 cm above the xiphoid on the ventral side; left‐arm ECG electrode positioned along the costal margin. (b) Our original method: right‐arm electrode positioned 5 cm above the xiphoid on the dorsal side; left‐arm electrode positioned along the costal margin. Results The CMAP amplitude during right phrenic nerve pacing was significantly higher at the dorsal side than the ventral side (0.80 ± 0.31 mV vs 0.66 ± 0.29 mV, P, The amplitude of diaphragmatic compound motor action potentials was significantly high at the dorsal side of the xiphoid compared to the conventional ventral side. Monitoring phrenic nerve function using an electrocardiography (ECG) electrode at the dorsal side is a simple and easy procedure.

Background: Frailty is a complex clinical syndrome associated with ageing and chronic illness, and is common in heart failure (HF). Vascular endothelial dysfunction including maladaptive angiogenesis and lymphangiogenesis is involved in the pathogenesis of HF, and is also considered to be the causes of frailty. We investigated the association of vascular endothelial growth factor (VEGF) families, central regulators of angiogenesis and lymphangiogenesis, with frailty, and prognostic role of these cytokines in frail HF patients. Methods: We performed a multicenter prospective cohort study to determine the predictive value of VEGF families for prognosis among patients with HF. A total of 1,024 patients (mean age, 75.5 years, 58.7% male) were included in the analyses. Serum levels of VEGF, VEGF-C, VEGF-D, and soluble VEGF receptor-2 (sVEGFR-2) were measured. Frailty was assessed by Canadian Study of Health and Aging Clinical Frailty Scale (CFS). Results: A total of 256 (25.1%) patients had frailty (CFS≥5) at baseline. Frail patients were older, more likely female, and had lower body mass index, higher NYHA class, and higher rates of prior hospitalization for HF, HF with preserved ejection fraction, anemia, cerebrovascular disease, and dementia. N-terminal pro brain natriuretic peptide, high sensitivity troponin I, and high sensitivity C-reactive protein levels were higher in frail patients. During the 2-year follow-up, 211 all cause death occurred. In Kaplan-Maier analysis, frail patients showed significantly higher incidence of all-cause (hazard ratio [HR], 4.12; 95% confidence interval [CI], 3.14-5.42). Regarding VEGF families, frail patients had significantly lower levels of sVEGFR-2 and VEGF-C, and higher levels of VEGF-D. Multiple regression analysis revealed that VEGF-C had inverse correlation with CFS (P, 0.03). After adjusting for clinical confounders, a low VEGF-C level was independently associated with all-cause death in frail patients (HR, 0.74; 95%CI, 0.58-0.94 for 1-SD increase), but was not in non-frail patients (HR, 0.87; 95%CI, 0.64-1.14 for 1-SD increase) (P for interaction, 0.09). Conclusions: In HF patients, a low VEGF-C value was associated with frailty and was independent risk for all-cause death in frail patients.

Background The lymphatic system has been suggested to play an important role in cardiovascular (CV) diseases including heart failure (HF). Vascular endothelial growth factor C (VEGF-C) and VEGF-D are key regulators of lymphoangiogenesis. Purpose To investigate the association of VEGF-C and VEGF-D with prognosis in patients with chronic HF (CHF). Methods The PREHOSP-CHF study is a multicenter prospective cohort study to determine the predictive value of angiogenesis-related biomarkers in CHF. A total of 1,024 patients (mean age, 75.5±12.6 years; male, 58.7%) admitted to acute decompensated HF were included in the analyses. The primary outcome was MACE defined as a composite of CV death or HF hospitalization. The secondary outcomes were all-cause death, CV death, and HF hospitalizations. Serum levels of VEGF-C and VEGF-D, as well as N-terminal pro B-type natriuretic peptide (NT-proBNP), high sensitivity cardiac troponin-I (hs-cTnI), high sensitive C reactive protein (hs-CRP), VEGF, and soluble VEGF receptor-2 (sVEGFR-2) were measured at the time of discharge. Patients were followed-up over two years. Results Median [interquartile range] of VEGF-C and VEGF-D levels were 4821 [3633–6131] pg/ml and 404 [296–559] pg/ml, respectively. In multivariate stepwise regression analysis, independent determinants of VEGF-C levels were younger age, female gender, absence of prior HF hospitalization, chronic kidney disease, and anemia, lower ejection fraction, lower NT-proBNP levels, higher VEGF levels, and higher sVEGFR-2 levels, while those of VEGF-D levels were lower body mass index, presence of diabetes and atrial fibrillation, and higher NT-proBNP levels. During the follow-up, a total of 209 (20.4%) all-cause deaths, 112 (10.9%) CV deaths, and 309 (30.2%) HF hospitalizations occurred. After adjusting for established risk factors and CV biomarkers, VEGF-C levels were significantly and inversely associated with the incidence of MACE and non-CV death (Fig.1, model 4). On the other hand, VEGF-D levels were significantly and positively associated with the incidence of HF hospitalization (Fig. 1, model 4). When we divided the patients into 4 groups based on the median of VEGF-C and VEGF-D levels, patients with low VEGF-C and high VEGF-D showed significantly higher incidence of MACE, all-cause death, CV death, and HF hospitalization compared to those with high VEGF-C and low VEGF-D (Fig. 2). Conclusions Among patients with CHF, VEGF-C and VEGF-D had different characteristic and association with the incidence of adverse events. VEGF-C levels were inversely associated with the incidence of MACE and non-CV death, and VEGF-D levels were positively associated with the incidence of HF hospitalization. These results suggests different effects of VEGF-C and VEGF-D in CHF. Combination of VEGF-C and VEGF-D enables us to make good risk stratification in patients with CHF. Funding Acknowledgement Type of funding sources: Public grant(s) – National budget only. Main funding source(s): Grant-in-Aid for Clinical Research from the National Hospital Organization Figure 1Figure 2

Aims Endothelial cell vascular endothelial growth factor receptor 2 (VEGFR‐2) plays a pivotal role in angiogenesis, which induces physiological cardiomyocyte hypertrophy via paracrine signalling between endothelial cells and cardiomyocytes. We investigated whether a decrease in circulating soluble VEGFR‐2 (sVEGFR‐2) levels is associated with poor prognosis in patients with chronic heart failure (HF). Methods and results We performed a multicentre prospective cohort study of 1024 consecutive patients with HF, who were admitted to hospitals due to acute decompensated HF and were stabilized after initial management. Serum levels of sVEGFR‐2 were measured at discharge. Patients were followed up over 2 years. The outcomes were cardiovascular death, all‐cause death, major adverse cardiovascular events (MACE) defined as a composite of cardiovascular death and HF hospitalization, and HF hospitalization. The mean age of the patients was 75.5 (standard deviation, 12.6) years, and 57% were male. Patients with lower sVEGFR‐2 levels were older and more likely to be female, and had greater proportions of atrial fibrillation and anaemia, and lower proportions of diabetes, dyslipidaemia, and HF with reduced ejection fraction (

This letter describes a newly established design framework with the layered architecture of processing elements (PEs) exploiting high-level synthesis and its evaluation results. The design framework was developed for intelligent sensor nodes of Internet of Things applications that collaborate with cloud systems, in which small footprint and low power consumption were major concerns. The design framework consists of four layered structure of PE architecture with the extended database management function of a high-level synthesis tool. We investigated the dependencies of resource consumption on the granularity of coarse grained function definitions using the extended database management function of CyberWorkBench. The evaluation results showed that small footprint was achieved especially with dynamically reconfigurable technique.

Background: High circulating levels of galectin-3 are associated with all-cause mortality, cardiovascular (CV) mortality, and/or major adverse CV events (MACE) in patients with CV diseases such as heart failure and coronary artery disease (CAD). However, the impact of sex on the prognostic value of galectin-3 in patients with suspected or known CAD remains unclear. Methods: Using data from a multicenter, prospective cohort of 2418 patients with suspected or known CAD, we assessed the impact of sex on the association between galectin-3 levels and the risks of all-cause death, CV death, and MACE defined as a composite of CV death, nonfetal myocardial infarction, and nonfetal stroke. Galectin-3 was measured in 1624 men and 794 women enrolled in the ANOX Study. Patients were followed up over 3 years. Results: The mean ages (standard deviations) were 69.8 (10.6) years in men and 72.2 (9.9) years in women ( P P =0.004). In the entire patient cohort, the galectin-3 level was significantly associated with all-cause death (hazard ratio per 1 standard deviation increase [HR], 1.28; 95% confidence interval [CI], 1.16-1.42), CV death (HR, 1.24; 95% CI, 1.04-1.46), and MACE (HR, 1.24; 95% CI, 1.09-1.41) after adjusting for potential clinical confounders. These associations were still significant in women (HR for all-cause death, 1.59; 95% CI, 1.26-1.98; HR for CV death, 1.53; 95% CI, 1.06-2.21; HR for MACE, 1.61; 95% CI, 1.21-2.09), whereas in men, galectin-3 was significantly associated with all-cause death (HR, 1.23; 95% CI, 1.08-1.39), but not with CV death (HR, 1.14; 95% CI, 0.93-1.40) or MACE (HR, 1.15; 95% CI, 0.99-1.35). Furthermore, galectin-3 provided incremental prognostic information for all-cause death, but not for CV death or MACE, to the model with potential clinical confounders and the established CV biomarkers in the entire cohort and in women, but not in men. Conclusions: We identified a significantly stronger prognostic value of galectin-3 in women than in men among patients with suspected or known CAD.

Background: Smoking is a risk factor for mortality in the general population and in patients with coronary artery disease (CAD). Vascular endothelial growth factor D (VEGF-D) is a secreted glycoprotein that can act as lymphangiogenic and angiogenic growth factors. Recently, we demonstrated that circulating VEGF-D levels are associated with the risk of mortality in patients with suspected or known CAD. However, whether VEGF-D levels differ according to smoking status and whether smoking modifies the relationship between VEGF-D and mortality in those patients are unknown. Methods: Using data from a multicenter, prospective cohort of 2418 patients with suspected or known CAD, we assessed the association between smoking status and VEGF-D and the impact of smoking status on the association between VEGF-D levels and the risk of all-cause death. VEGF-D was measured in 955 never smokers, 1035 former smokers, and 428 current smokers enrolled in the ANOX Study. Patients were followed up over 3 years. Results: The mean age (standard deviation [SD]) of the patients was 70.6 (10.4) years; 67.2% were men. Current smokers exhibited significantly higher levels of VEGF-D compared to former smokers and never smokers (median [interquartile range], 343 [214-556], 312 [201-500], 291 [182-485] pg/mL, respectively; P =0.006). Stepwise multiple linear regression analysis revealed that the log-transformed VEGF-D level was independently associated with current smoking ( P =0.002), but not with former smoking. After adjusting for potential clinical confounders, the VEGF-D level was significantly associated with all-cause death in never smokers (hazard ratio per 1-SD increase [HR], 1.31; 95% confidence interval [CI], 1.10-1.55) and in former smokers (HR, 1.22; 95% CI, 1.08-1.37), but not in current smokers (HR, 0.92; 95% CI, 0.65-1.22). Furthermore, VEGF-D provided incremental prognostic information to the model with potential clinical confounders and the established cardiovascular biomarkers in never smokers, but not in former smokers or in current smokers. Conclusions: Current smoking was independently associated with higher levels of VEGF-D. The prognostic value of VEGF-D on mortality was most pronounced in never smokers among patients with suspected or known CAD.

Introduction: Soluble vascular endothelial growth factor receptor-2 (sVEGFR-2) acts as an endogenous inhibitor of VEGF, a key regulator of angiogenesis and lymphoangiogenesis. However, little is known about the critical role of sVEGFR-2 in heart failure (HF). Methods: We performed a multicenter prospective cohort study (PREHOSP-CHF Study) to determine the predictive value of sVEGFR-2 for major adverse cardiovascular (CV) events (MACE) among patients with chronic HF (CHF). A total of 1,021 patients were included in the analyses. The mean age (SD) was 75.5 (12.6) years. 59.6% were male. The primary outcome was MACE defined as a composite of CV death or HF hospitalization. The secondary outcomes were all-cause death and CV death. Serum levels of sVEGFR-2 were determined employing specific enzyme-linked immunosorbent assays. Results: The patients with lower sVEGFR-2 concentrations were older, and had higher rates of female sex, atrial fibrillation and anemia. The baseline sVEGFR-2 level was inversely correlated with left ventricular ejection fraction, and was positively correlated with the body mass index. During the median follow-up of 730 days, a total of 210 (20.6%) all-cause deaths, 99 (9.7%) CV deaths and 308 (30.2%) HF hospitalizations occurred. Unadjusted Cox proportional hazard analyses revealed that the patients with the lowest quartile (Q1) of sVEGFR-2 did not show a significantly higher risk of MACE (p=0.7), but showed the greatest risks of CV death (p=0.003) and all-cause death (p=0.007). Even after adjusting for established risk factors and CV biomarkers (N-terminal pro-brain natriuretic peptide, contemporary sensitive cardiac troponin-I, and high-sensitivity C-reactive protein), those with the Q1 of sVEGFR-2 exhibited the greatest risk of CV death (p=0.02; hazard ratio [HR], 2.05; 95% confidence interval [CI], 1.17-3.66 [vs. Q2]; HR, 2.42; 95%CI, 1.30-4.68 [vs. Q3]; HR, 1.52; 95%CI, 0.80-2.99 [vs. Q4]), but not that of all-cause death. The sex-stratified analyses revealed that the association between sVEGFR-2 and CV death was still significant in men, but not in women (p for interaction, 0.07). Conclusions: A low sVEGFR-2 value was not associated with MACE, but was independently associated with CV mortality among patients with CHF.

Background: The impact of chronic kidney disease (CKD) on the association of cardiovascular (CV) and renal biomarkers with the presence and severity of coronary artery disease (CAD) in patients with suspected CAD are unclear. Methods: Using data from a multicenter, prospective cohort of 2324 patients with suspected but no history of CAD undergoing elective coronary angiography, we assessed the impact of CKD on the association of CV and renal biomarkers with the presence and severity of CAD. Heparin-free fasting serum levels of soluble vascular endothelial growth factor (VEGF) receptor-1 (sFlt-1), VEGF, placental growth factor (PlGF), N-terminal pro-brain natriuretic peptide (NT-proBNP), contemporary sensitive cardiac troponin-I (cTnI), high-sensitivity CRP (hs-CRP), cystatin C, and neutrophil gelatinase-associated lipocalin (NGAL) were measured in 887 CKD and 1437 non-CKD patients enrolled in the EXCEED-J study. The severity of CAD was quantified using the Gensini score. Results: The mean age (standard deviation) of the patients was 69.8 (10.8) years; 65.6% were men. Serum levels of all biomarkers except PlGF were significantly higher in CKD than in non-CKD patients. In the entire patient cohort, only natural log-transformed (Ln-) cTnI was significantly associated with CAD, multi-vessel or left main trunk disease (MVD/LMTD), and Ln-Gensini score after adjustment for potential confounders. These associations were still significant in non-CKD, but not in CKD: Ln-cTnI was significantly associated with MVD/LMTD and Ln-Gensini score, but not with CAD. Stepwise regression analyses including potential confounders and all biomarkers revealed that Ln-cTnI was independently associated with CAD, MVD/LMTD, and Ln-Gensini score in the entire cohort and in non-CKD, but not in CKD: Ln-cTnI was independently associated with MVD/LMTD and Ln-Gensini score, but not with CAD. No other biomarker exhibited an independent association with CAD, MVD/LMTD, or Ln-Gensini score in the entire cohort, in non-CKD, or in CKD. Conclusions: Among CV and renal biomarkers measured in this study, only Ln-cTnI was independently associated with the presence and severity of CAD in patients with suspected CAD. These associations were attenuated in patients with CKD.

Background: Diabetes mellitus (DM) is still significantly associated with the risk of mortality in the general population. Higher circulating growth differentiation factor 15 (GDF-15) levels are associated with the risk of mortality in the general population, in patients with DM, and in those with coronary artery disease (CAD). However, whether GDF-15 levels differ according to the diabetic status and whether DM modifies the relationship between GDF-15 and mortality in patients with stable CAD are unclear. Methods: Using data from a multicenter, prospective cohort of 1460 patients with stable CAD, we assessed the association between diabetic status and GDF-15 and the impact of DM on the association between GDF-15 levels and the risk of all-cause death. GDF-15 was measured in 797 DM and 663 non-DM patients enrolled in the ANOX Study. Results: The mean age (standard deviation [SD]) of the patients was 71.7 (9.4) years; 74.4% were men. Patients with DM exhibited significantly higher levels of GDF-15 compared to those without DM (median [interquartile range], 1472 [1049-2258] vs. 1274 [868-1874] pg/mL, respectively; P P Conclusions: Higher levels of GDF-15 were independently associated with DM in patients with stable CAD. The prognostic value of GDF-15 on mortality was pronounced in patients with DM.

Background: Growth differentiation factor 15 (GDF-15) is a stress responsive cytokine of the transforming growth factor superfamily. Circulating levels of GDF-15 are elevated in various conditions including anemia and stable coronary artery disease (CAD), and associated with the risk of mortality in patients with stable CAD. However, whether anemia modifies the relationship between GDF-15 and mortality in patients with stable CAD is unknown. Methods: Using data from a multicenter, prospective cohort of 1460 patients with stable CAD, we assessed the association between anemic status and GDF-15 and the impact of anemia on the association between GDF-15 levels and the risk of all-cause death. GDF-15 was measured in 564 anemic and 896 non-anemic patients enrolled in the ANOX Study. Results: The mean age (standard deviation [SD]) of the patients was 71.7 (9.4) years; 74.4% were men. Patients with anemia exhibited significantly higher levels of GDF-15 compared to those without anemia (median [interquartile range], 1953 [1302-3110] vs. 1175 [838-1579] pg/mL, respectively; P P Conclusions: Higher levels of GDF-15 were independently associated with anemia in patients with stable CAD. The prognostic value of GDF-15 on mortality was pronounced in patients with anemia.

Background Whether circulating growth differentiation factor 15 (GDF‐15) levels differ according to smoking status and whether smoking modifies the relationship between GDF‐15 and mortality in patients with coronary artery disease are unclear. Methods and Results Using data from a multicenter, prospective cohort of 2418 patients with suspected or known coronary artery disease, we assessed the association between smoking status and GDF‐15 and the impact of smoking status on the association between GDF‐15 and all‐cause death. GDF‐15 was measured in 955 never smokers, 1035 former smokers, and 428 current smokers enrolled in the ANOX Study (Development of Novel Biomarkers Related to Angiogenesis or Oxidative Stress to Predict Cardiovascular Events). Patients were followed up during 3 years. The age of the patients ranged from 19 to 94 years; 67.2% were men. Never smokers exhibited significantly lower levels of GDF‐15 compared with former smokers and current smokers. Stepwise multiple linear regression analysis revealed that the log‐transformed GDF‐15 level was independently associated with both current smoking and former smoking. In the entire patient cohort, the GDF‐15 level was significantly associated with all‐cause death after adjusting for potential clinical confounders. This association was still significant in never smokers, former smokers, and current smokers. However, GDF‐15 provided incremental prognostic information to the model with potential clinical confounders and the established cardiovascular biomarkers in never smokers, but not in current smokers or in former smokers. Conclusions Not only current, but also former smoking was independently associated with higher levels of GDF‐15. The prognostic value of GDF‐15 on mortality was most pronounced in never smokers among patients with suspected or known coronary artery disease.

Background VEGF‐D (vascular endothelial growth factor D) and VEGF‐C are secreted glycoproteins that can induce lymphangiogenesis and angiogenesis. They exhibit structural homology but have differential receptor binding and regulatory mechanisms. We recently demonstrated that the serum VEGF‐C level is inversely and independently associated with all‐cause mortality in patients with suspected or known coronary artery disease. We investigated whether VEGF‐D had distinct relationships with mortality and cardiovascular events in those patients. Methods and Results We performed a multicenter, prospective cohort study of 2418 patients with suspected or known coronary artery disease undergoing elective coronary angiography. The serum level of VEGF‐D was measured. The primary outcome was all‐cause death. The secondary outcomes were cardiovascular death and major adverse cardiovascular events defined as a composite of cardiovascular death, nonfatal myocardial infarction, and nonfatal stroke. During the 3‐year follow‐up, 254 patients died from any cause, 88 died from cardiovascular disease, and 165 developed major adverse cardiovascular events. After adjustment for possible clinical confounders, cardiovascular biomarkers (N‐terminal pro‐B‐type natriuretic peptide, cardiac troponin‐I, and high‐sensitivity C‐reactive protein), and VEGF‐C, the VEGF‐D level was significantly associated with all‐cause death and cardiovascular death but not with major adverse cardiovascular events.. Moreover, the addition of VEGF‐D, either alone or in combination with VEGF‐C, to the model with possible clinical confounders and cardiovascular biomarkers significantly improved the prediction of all‐cause death but not that of cardiovascular death or major adverse cardiovascular events. Consistent results were observed within patients over 75 years old. Conclusions In patients with suspected or known coronary artery disease undergoing elective coronary angiography, an elevated VEGF‐D value seems to independently predict all‐cause mortality.

Background ST-segment elevation myocardial infarction is known to be associated with worse short-term outcome than non-ST-segment elevation myocardial infarction. However, whether or not this trend holds true in patients with a high Killip class has been unclear. Methods We analyzed 3704 acute myocardial infarction patients with Killip II–IV class from the Japan Acute Myocardial Infarction Registry and compared the short-term outcomes between ST-segment elevation myocardial infarction (n = 2943) and non-ST-segment elevation myocardial infarction (n = 761). In addition, we also performed the same analysis in different age subgroups: Results In the overall population, there were no significant difference in the in-hospital mortality (20.0% vs 17.1%, p = 0.065) between ST-segment elevation myocardial infarction and non-ST-segment elevation myocardial infarction groups. Patients Conclusion Among cases of acute myocardial infarction with a high Killip class, there was no marked difference in the short-term outcomes between ST-segment elevation myocardial infarction and non-ST-segment elevation myocardial infarction in younger patients, while ST-segment elevation myocardial infarction showed worse short-term outcomes in elderly patients than non-ST-segment elevation myocardial infarction. Future study identifying the prognostic factors for the specific anticipation intensive cares is needed in this high-risk group.

Object detection and tracking are vital for video analysis. As the development of Deep Neural Network (DNN), multiple object tracking is recently performed on the detection results from DNN. However, DNN-based detection is computation-intensive. In order to accelerate multiple object detection and tracking for real-time application, we present a framework to import the tracking knowledge into detection to allow a less accurate but faster DNN for detection and recover the accuracy loss. By combining different DNNs with accuracy-speed trade-offs using space-aware color information, our framework achieves significant speedup (6.8\(\times \)) and maintains high accuracy. Targeting NVIDIA Xavier, we further optimize the implementation from system and platform level.

A regularization is integrated with Forward-Backward Time-Stepping (FBTS) method which is formulated in time-domain utilizing Finite-Difference Time-Domain (FDTD) method to solve the nonlinear and ill-posed problem arisen in the microwave inverse scattering problem. FBTS method based on a Polak-Ribiete-Polyak conjugate gradient method is easily trapped in the local minima. Thus, we extend our work with the integration of edge-preserving regularization technique due to its ability to smooth and preserve the edges containing important information for reconstructing the dielectric profiles of the targeted object. In this paper, we propose a deterministic relaxation with Mean Square Error algorithm known as DrMSE in FBTS and integrate it with the automated edge-preserving regularization technique. Numerical simulations are carried out and prove that the reconstructed results are more accurate by calculating the edge-preserving parameter automatically.

An initial-boundary value problem is set up whose solution coincides with that of the original scattering problem in the interior region bounded by the observation surface if and only if a medium inside the observation surface is the same as that of the original one. Based on this initial- boundary value problem, we present an inverse scattering method by using cost functional consisting the approximated stored energy with no information on incident field. A cost functional consisting of the approximated stored energy of the misfit field between the original problem and the boundary value problem with an estimated object is introduced to solve the inverse problem. Preliminary numerical examples are provided to assess the proposed inversion approach.