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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 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 (

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: 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.

Contains fulltext : 215333.pdf (Publisher’s version ) (Closed access) BACKGROUND: Patients with stable coronary artery disease and diabetes with previous percutaneous coronary intervention (PCI), particularly those with previous stenting, are at high risk of ischaemic events. These patients are generally treated with aspirin. In this trial, we aimed to investigate if these patients would benefit from treatment with aspirin plus ticagrelor. METHODS: The Effect of Ticagrelor on Health Outcomes in diabEtes Mellitus patients Intervention Study (THEMIS) was a phase 3 randomised, double-blinded, placebo-controlled trial, done in 1315 sites in 42 countries. Patients were eligible if 50 years or older, with type 2 diabetes, receiving anti-hyperglycaemic drugs for at least 6 months, with stable coronary artery disease, and one of three other mutually non-exclusive criteria: a history of previous PCI or of coronary artery bypass grafting, or documentation of angiographic stenosis of 50% or more in at least one coronary artery. Eligible patients were randomly assigned (1:1) to either ticagrelor or placebo, by use of an interactive voice-response or web-response system. The THEMIS-PCI trial comprised a prespecified subgroup of patients with previous PCI. The primary efficacy outcome was a composite of cardiovascular death, myocardial infarction, or stroke (measured in the intention-to-treat population). FINDINGS: Between Feb 17, 2014, and May 24, 2016, 11 154 patients (58% of the overall THEMIS trial) with a history of previous PCI were enrolled in the THEMIS-PCI trial. Median follow-up was 3.3 years (IQR 2.8-3.8). In the previous PCI group, fewer patients receiving ticagrelor had a primary efficacy outcome event than in the placebo group (404 [7.3%] of 5558 vs 480 [8.6%] of 5596; HR 0.85 [95% CI 0.74-0.97], p=0.013). The same effect was not observed in patients without PCI (p=0.76, pinteraction=0.16). The proportion of patients with cardiovascular death was similar in both treatment groups (174 [3.1%] with ticagrelor vs 183 (3.3%) with placebo; HR 0.96 [95% CI 0.78-1.18], p=0.68), as well as all-cause death (282 [5.1%] vs 323 [5.8%]; 0.88 [0.75-1.03], p=0.11). TIMI major bleeding occurred in 111 (2.0%) of 5536 patients receiving ticagrelor and 62 (1.1%) of 5564 patients receiving placebo (HR 2.03 [95% CI 1.48-2.76], p

We present an inverse scattering method using only total electric field data on an observation surface with no knowledge of incident fields. 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. A cost functional consisting the 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.

In this paper, a Frequency-Dependent Forward-Backward Time-Stepping (FD-FBTS) inverse scattering technique is used for reconstruction of homogeneous dispersive object. The aim of the technique is to reconstruct the relative permittivity at infinite frequency, static relative permittivity and static conductivity of the homogeneous dispersive object simultaneously. The technique utilizes iterative finite-difference time-domain (FDTD) method for solving inverse scattering problem in time domain. The minimization of the cost functional is carried out utilizing Dai-Yuan nonlinear conjugate-gradient algorithm. The Frechet derivatives of the augmented cost functional are derived analytically with respect to scatterer properties. Numerical results for reconstruction of two-dimensional homogeneous dispersive illustrate the performance of the proposed technique.

Background Hypertension, diabetes, dyslipidemia and smoking are established coronary risk factors for coronary heart disease in the general population. However, in Japanese patients with acute myocardial infarction (AMI), the impact of the number of coronary risk factors on in-hospital morality remains unclear. Methods The Japan Acute Myocardial Infarction Registry (JAMIR) is a nationwide real-world database. We examined the association between the number of coronary risk factors and in-hospital mortality. Results Data were obtained from total of 20462 AMI patients (mean age, 68.8 ± 13.3 years old; 15281 men, 5181 women). The prevalence of hypertension increased with advancing age, while the prevalence of smoking decreased with advancing age. The prevalence of diabetes and dyslipidemia were highest in middle age. A majority (76.9%) of the patients with AMI had at least 1 of these coronary risk factors. Overall, the number of coronary risk factor was relatively less in older subjects and women under 50 years old. Crude in-hospital mortality rates were 10.7%, 10.5%, 7.2%, 5.0% and 4.5% with 0, 1, 2, 3 and 4 risk factors, respectively. After adjusting for age and sex, there was an inverse association between the number of coronary risk factors and the in-hospital mortality (adjusted odds ratio [1.68; 95% confidence interval, 1.20–2.35] among individuals with 0 vs. 4 risk factors). Conclusion In the present study of Japanese patients with AMI, who received modern medical treatment, in-hospital mortality was inversely related to the number of coronary risk factors. To investigate the underlying reasons for these findings, further studies are needed.

International audience; The structural health monitoring of cultural heritages is addressed in this paper. The arising inverse problem is solved through the Learning-by-Examples (LBE) paradigm, exploiting data collected by a Wireless Sensor Network (WSN). More in detail, low-cost and low-size sensing devices are spread over the scenario to be monitored, allowing environmentaldata as well as acceleration and vibration information to be acquired and processed by means of a Support Vector Machine (SVM) in order to detect the presence/absence of a damage in the monitored structure. The proposed approach has been preliminary validated in a laboratory controlled environment, demonstrating promising performance.

Background The lymphatic system has been suggested to play an important role in cholesterol metabolism and cardiovascular disease. However, the relationships of vascular endothelial growth factor‐C ( VEGF ‐C), a central player in lymphangiogenesis, with mortality and cardiovascular events in patients with suspected or known coronary artery disease are unknown. 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 primary predictor was serum levels of VEGF ‐C. 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, non‐fatal myocardial infarction, and non‐fatal 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 established risk factors, VEGF ‐C levels were significantly and inversely associated with all‐cause death (hazard ratio for 1‐ SD increase, 0.69; 95% confidence interval, 0.60–0.80) and cardiovascular death (hazard ratio, 0.67; 95% confidence interval, 0.53–0.87), but not with major adverse cardiovascular events (hazard ratio, 0.85; 95% confidence interval, 0.72–1.01). Even after incorporation of N‐terminal pro‐brain natriuretic peptide, contemporary sensitive cardiac troponin‐I, and high‐sensitivity C‐reactive protein into a model with established risk factors, the addition of VEGF ‐C levels further improved the prediction of all‐cause death, but not that of cardiovascular death or major adverse cardiovascular events. Consistent results were observed within 1717 patients with suspected coronary artery disease. Conclusions In patients with suspected or known coronary artery disease, a low VEGF ‐C value may independently predict all‐cause mortality.

This chapter introduces the applications of the Flexible Reliability Reconfigurable Array (FRRA) processors, which is presented in Sect. 3.4, in a non-von Neumann architecture, and discusses its advantages when it is used in the Internet of Things (IoT) applications. FRRA is an embodiment of the concept of embedded automaton that we introduce as an essential element for building the IoT. We will start by looking at the role played by embedded system processors and point out that employing non-von Neumann architecture is inevitable (essential) to accomplish the speed/power performance required for embedded system applications. The major target application of embedded microprocessor is the IoT, and space-born sensor applications are quoted in this chapter as examples of the IoT. Space systems are somewhat special but are typical IoT applications which require dependability as an essential feature. Another important aspect of the embedded automaton based on the FRRA architecture is the contribution of behavioral synthesis technology. Practical application implementation on the reconfigurable processor is realized with the maturity of a high-level behavioral synthesis technology called CyberWorkBench (CWB).

Memcached has been widely accepted as a technology to improve the response speed of web servers by caching data on DRAMs in distributed servers. Because of its importance, the acceleration of memcached has been studied on various platforms. Among them, FPGA looks the most attractive platform to run memcached, and several research groups have tried to obtain a much higher performance than that of CPU out of it. The difficulty encountered there, however, is how to manage large-sized memory (gigabytes of DRAMs) from memcached hardware built in an FPGA. Some groups are trying to solve this problem by using an embedded CPU for memory allocation and another group is employing an SSD. Unlike other approaches that try to replace memcached itself on FPGAs, our approach augments the software memcached running on the host CPU by caching its data and some operations at the FPGA- equipped network interface card (NIC) mounted on the server. The locality of memcached data enables the FPGA NIC to have a fairly high hit rate with a smaller memory. In this paper, we describe the architecture of the proposed NIC cache, and evaluate the effectiveness with a standard key-value store (KVS) benchmarking tool. Our evaluation shows that our system is effective if the workload has temporal locality but does not handle workloads well without such a characteristic. We further propose methods to overcome this problem and evaluate them. As a result, we estimate that the latency improved by up to 3.5 times over software memcached running on a high performance CPU.

Network Function Visualization (NFV) is becoming a new networking architecture for telecom carriers. NFV achieves network functions with software and commercial off the shelf (COTS) servers instead of dedicated hardware. While the software-based approach is expected to reduce costs, it could cause performance issues. CPU-FPGA tightly coupled architectures may be available in COTS servers in the near future. This paper proposes accelerating NFV application leveraging such a CPU-FPGA architecture. The proposed method of acceleration uses a data plane development kit (DPDK) ring queue, which is often used in network software, as the communication interface between the FPGA and CPU. We propose two optimizations for ring operation and table lookup operation to efficiently use the bus between FPGA and CPU. We evaluated the proposed method with an actual CPU+FPGA based platform, and an NFV application, i.e., vCPE. The results revealed that the evaluation system could accommodate 2 × 40-GbE Internet traffic, and could increase capacity as a vCPE server by x1.33.

Background The prevalence of atrial fibrillation (AF) is high in elder subjects. Our previous observational study suggested that vitamin K antagonist (VKA) promotes aortic valve degeneration, a principal cause of aortic stenosis in the elderly, and that angiotensin receptor blocker (ARB) attenuates its progression. This study aimed to prospectively investigate these observations in non-valvular AF patients. Methods Of enrolled 430 patients with calcification on no or one aortic valve leaflet, all of the planned 4-year follow-up data were obtained in 122 non-valvular AF patients treated with warfarin (warfarin group) and 101 patients with cardiovascular diseases and without AF and prescription of warfarin (non-warfarin group). Results Despite higher atherosclerotic risks in the non-warfarin group, 2 or 3 newly calcified leaflets emerged during 4 years in 18.0% of patients in the warfarin group and in 6.9% in the non-warfarin group (p = 0.014). Aortic valve area (AVA) did not significantly change in the non-warfarin group during the follow-up, but tended to decrease in the warfarin group (p = 0.057). Non-vitamin K antagonist oral anticoagulant got available in Japan after this study started, and warfarin was discontinued in 15 patients of the warfarin group. The reduction of AVA was significant in the remaining 107 patients on the continuous warfarin treatment (p = 0.002). The effects of ARB on AVA were obscure. Conclusion Major bleeding associated with VKA is well recognized. This study suggests that the development of aortic valve degeneration is another risk of long-term use of VKA in non-valvular AF patients with no or mild aortic valve degeneration.

An inverse scattering approach using only total electric field data is developed for reconstructing electrical parameters of unknown scatterers. Two interior boundary value problems are set up whose solutions coincide with each other if and only if a medium inside the observation surface is the same as that of the original scattering problem. A cost functional of misfit between the two solutions is introduced to solve the inverse problem and its gradient is derived explicitly. Numerical examples are provided to assess the proposed inversion approach. © 2015 Wiley Periodicals, Inc. Microwave Opt Technol Lett 57:137–141, 2015

A 68-year-old woman with a history of hypertension was admitted to our hospital because of dyspnea during physical exertion. Echocardiography demonstrated impaired left ventricular systolic function, and her ejection fraction was reduced to 30%. Coronary angiography did not show significant stenosis. Endomyocardial biopsy showed only nonspecific findings without noncaseating granulomas. Cardiac magnetic resonance (CMR) imaging showed transmural late gadolinium enhancement on the basal part of the left ventricle. 18F-Fluorodeoxyglucose positron emission tomography (18F-FDG PET) showed abnormal focal uptake specific to the left ventricle; no abnormal manifestations in other organs were observed. The CMR and 18F-FDG PET features could not rule out either sarcoidosis or malignant lymphoma. Therefore, we conducted open-chest myocardial biopsy to differentiate between the two possible diseases. Histopathological findings showed noncaseating epithelioid cell granuloma, confirming isolated cardiac sarcoidosis. This is an example of a challenging case of diagnosing isolated cardiac sarcoidosis. .

This brief presents an efficient complex event-processing framework, designed to process a large number of sequential events on field-programmable gate arrays (FPGAs). Unlike conventional structured query language based approaches, our approach features logic automation constructed with a new C-based event language that supports regular expressions on the basis of C functions, so that a wide variety of event-processing applications can be efficiently mapped to FPGAs. Evaluations on an FPGA-based network interface card show that we can achieve 12.3 times better event-processing performance than does a CPU software in a financial trading application.

An inverse scattering approach based on the field equivalence principle is developed for reconstructing the electrical parameters of a stratified medium using only electric field time-domain data measured at two observation points in presence and absence of the medium. The magnetic field data at the observation points are calculated from the electric field data by solving two equivalent problems for the incident and scattered fields. By noting that the field of an equivalent problem for the total field in the interior region between two observation points is null in the exterior region, the functional of the electrical parameters is introduced. A genetic algorithm is applied for minimization of the functional to estimate the parameters. Numerical simulations demonstrate the effectiveness of the approach. © 2013 Wiley Periodicals, Inc. Int J RF and Microwave CAE, 2013.

International audience; Imaging techniques exploiting sparseness-regularized formulations emerged in the last few years as powerful and effective retrieval methods in several heterogeneous scenarios [1] including structural monitoring, non-destructive testing and evaluation, ground penetrating radar imaging, and biomedical diagnosis [2-8]. The success of the this class of algorithms, which are often collectively indicated as Compressive Sensing (CS) [9], is motivated by several concurring factors, including their accuracy, robustness, numerical efficiency, capability to handle several different contexts (e.g., including transverse-magnetic [2] and transverse-electric problems [3], single-/multi-frequency data [2, 4], isotropic/anisotropic media [1]) in a seamless way, and the availability of efficient implementations of many different solvers [1]. On the other hand, CS techniques are not general-purpose imaging algorithms. Their application requires the problem at hand to comply with some fundamental assumptions [1], including the fact that the unknown (e.g., the contrast [8] or equivalent currents [9]) is sparse in the employed basis. Early applications of CS methods, which used simple pixel-bases to expand the unknowns, addressed only those scenarios were the object is composed by few isolated pixels [2]. Nevertheless, it is well known that sparsity is not an absolute concept, but it is always in relation with the representation basis [1]. The use of different expansion bases [10] has been then proposed to enable more complex profiles to be imaged [7]. Unfortunately, such techniques always assume that some knowledge on the target profile is available, so that this a-priori information can be exploited to define the most suitable expansion basis to be adopted [7]. A different perspective is considered in this paper to enable the application of CS methodologies when no prior information on the class of targets under investigation is available. More specifically, a large alphabet of candidate bases is generated off-line, and for each basis a candidate reconstructions are carried out in parallel “online” by the CS retrieval tool. The retrieved profiles are then compared, and a sparsity-based criterion is adopted in turns to select the most reliable reconstruction (among those obtained by the different bases). Preliminary numerical experiments will be shown to assess the accuracy and numerical efficiency of the proposed imaging methodology

International audience; Summary form only given. In the last few years, the possibility to engineer the properties of artificial Metamaterials at microwave, THz, and optical frequencies has represented one of the key factors enabling the study, development, and demonstration of effective electromagnetic cloaks [1]. Indeed, several devices have been proposed which are able to manipulate the wave propagation not only to reduce radar cross section, but also to mitigate mutual coupling in close radiators and to reduce antenna backscattering [1]. In this framework, “perfect cloaks” have been initially designed through Transformation Electromagnetics (TE) methodologies [1]. Such techniques are based on the formulation of the cloaking problem as a “geometry deformation” one, in which the target is made invisible by “bending” the wave around it [1]. Unfortunately, the effectiveness of TE-based devices, numerically demonstrated in several different scenarios [2-5], can be obtained only if inhomogeneous and anisotropic permittivity and permeability tensors can be synthesized. In order to overcome this issue, alternative cloaking strategies based on the Scattering Cancellation principle have been proposed [6-10]. In this case, the cloak is made of a set of patterned metasurfaces covering the scatterer, whose properties are not aimed at bending the wave, but rather at enforcing that the combined scattering contributions of the target and the mantle cancel out [6-10]. Despite their effectiveness and potentialities [6-10], standard scattering cancellation methods are usually applied to thin dielectric/metallic cylinders since the design of multi-layer cloaks, required for “large” targets, is a theoretically and computationally challenging task (also because of the arising mutual coupling among the layers). To address this challenge, an instance of the System-by-Design paradigm [11] will be proposed in this work. Towards this end, the design of multi-layer mantle cloaks based on patterned metasurfaces and able to reduce the radar cross section of large dielectric cylinders will be reformulated as a task-oriented SbD problem. More specifically, (i) the objective will be the minimization of the scattering coefficients of the overall structure (taking into account mutual coupling effects), which will be encoded in a suitable cost function, and (ii) the degrees-of-freedom will be the patterns of each metasurface comprised in the cloak. Thanks to the capability of the SbD paradigm to formulate the design problem in a modular way, the most proper methodology will be adopted for each one of the functional blocks constituting the synthesis process [11]. The effectiveness of the resulting SbD-enhanced devices will be demonstrated through selected numerical experiments.

Forward-Backward Time-Stepping Method (FBTS method) is a technique to solve time domain inverse scattering problem. An incident pulse is radiated to unknown object. The scattering wave is measured at M points. A similar measurement is carried out at N different incident points. Total number of measured data is M × N. In FBTS method, the estimated field is calculated by FDTD method. The number of calculation on FDTD method is required only the number of incident points. Most on computing time by FBTS method is occupied by calculation of FDTD method. Therefore the method that the incident pulse was emitted at the same time at N different point was suggested. In this method, computing time becomes about 1/N compared with a usual FBTS method. However accuracy of reconstruction image degrades. In this research, time-delay FBTS method is proposed. The number of the measured electric field is M × N like a normal FBTS method. In the case of a linear medium, a theorem of the superposition holds good. Therefore, the total electric fields at each observation points are got by adding measured field for each incidence pulse when a pulse was radiated at the same time at different incident points. It is not necessary to be simultaneous the start time of electromagnetic pulse emitted from each incident point. That is, the start time of the radiation pulse can be changed by the incident points. Difference between the start times of the radiation pulses is referred to as a time-delay. Different time-delay is given the different total electric field. It's possible to get a measured field of many simultaneous incidences by introducing different time-delay to the same measured field. It's possible to improve the accuracy of the reconstruction image by using some delay times. Also, when time delay becomes longer than observation time to radiation of a pulse, presented method becomes same as a usual FBTS method. The validity of the presented technique is indicated by some numerical simulations.

An inverse scattering problem of determining the electrical property of an unknown dielectric object is considered. The electromagnetic wave generated by an impressed electric current with a short duration time illuminates the dielectric object. The measured data of the total field, the sum of the incident and scattered fields, over an observation surface S is used to reconstruct the electrical property distributions of the object without explicit information on the incident field. Using the tangential component of the electric field over the observation surface S, we can set up a boundary value problem which is equivalent to the original direct scattering problem in the interior region Ω i bounded by the surface S. Suppose that the total field data is measured over the observation surface S till the time t = T by which almost all the total energy leaves the interior region Ω i through the surface S and the field in the interior region becomes negligibly small. In this interior equivalent problem, the electrical property distribution must be the same as in the original scattering problem, i.e., the scattering object placed in the interior region must be the same as the original one. If a different object is placed in the interior region, reflection occurs on the surface in order for the total field to satisfy the boundary value. The reflected wave keeps bouncing in the interior region and remains even after the end time T of measurement. Noting this fact, we introduce the following functional of the electrical property distribution p(r): equation where η is the intrinsic impedance of free space, and Eeq(p; r, T) and Heq(p; r, T) are the electric and magnetic fields at the time t = T of the boundary value problem with the electrical property distribution p. If the distribution p is identical to the original one, the equivalent electric and magnetic fields are null at the time t = T. Therefore, the inverse problem is reduced to finding a minimizer of the functional Q(p). We apply a conjugate gradient method to the minimization problem. Several numerical simulations show the validity of the proposed method.

Time reversal imaging methods have received considerable attention since they yield accurate location estimate of point scatterers. Up to now, most time reversal methods have focused on detection and localization of point-like or small targets [1, 2] and not dealt with estimation of electrical parameter profile of scatterers. We have proposed a gradient based time-reversal imaging technique which can reconstruct electrical parameter distributions of the unknown object [3]. This method is based on the field equivalence principle and does not require the explicit knowledge of the incident field [4]. In this problem, the following functional of the parameters equation is to be minimized equation where equation is the region exterior to the measurement surface S and T is the measurement time. The field u n (p; r, t) is the solution of Maxwell equation for time reversed fields with the estimated parameters p under the n-th illumination. The quantity c is the light speed of the background. Due to the nonlinearity of the inverse scattering problem, the solution based on gradient methods often gets trapped into a local minimum. In order to avoid this problem, the filtered forward-backward time-stepping (FBTS) technique is used [5]. In this technique, the measured total field data is processed through a low-pass filter with several cut-off frequency sequences and these filtered data are solved by FBTS method. Numerical simulations show the effectiveness of the proposed method.

In this paper, an approach based on the field equivalence principle for obtaining the information of the incident field from total field data is presented. In general, the incident field is not easy to know because it is related to not only the impressed source but also the characteristics of the transmitting antenna and the surrounding environment of the source. By using this approach, the incident electric field is calculated from only total field data measured on a closed line, which is very useful for inverse scattering. Preliminary numerical simulations for some two dimensional scatterers show that the fields extracted from total field data are almost equal to the incident fields illuminating a scatterer of interest.

Power analysis for IoT devices is strongly required to reduce power consumption and realize secure communications. In this paper, we propose a scalable and small-sized power analyzer with signal-averaging noise reduction for low-power IoT devices. The proposed power analyzer reduces a wide frequency range of noises by using a signal averaging method and is implemented on just a 2cmx3cm board, which is the smallest size among the other existing power analyzers for IoT devices. It further has the following advantages: (a) It has a two-level amplifier that amplifies current signals adaptively depending on their magnitude. Hence maximum readable current can be increased with keeping minimum readable current small enough. (b) If long-time analysis is required, it can be partitioned into several analysis segments. The proposed power analyzer can measure currents and voltages of each analysis segment by using a small amount of data memories. After that, by combining these analysis segments using a timer module, we can obtain long-time analysis results. We have analyzed power and energy consumption of encryption processes of AES block cipher on the IoT device and demonstrated that the proposed power analyzer has only 1.8% measurement error compared with a high-precision oscilloscope.

A novel inverse scattering approach in time domain is presented for reconstructing electrical parameters of a stratified slab. The approach based on the field equivalence principle does not need explicit information of incident fields. Considering a problem equivalent to the original scattering problem inside the region bounded by the measurement points, a cost functional of electrical parameters of the slab is introduced. The minimization of the functional is achieved by a genetic algorithm. Numerical simulations of reconstructing the relative permittivity of a stratified dielectric slab demonstrate the efficacy of the proposed method., IEICE Electronics Express, 9(15), pp.1243-1248; 2012

We report a case of clonic-tonic seizures diagnosed using an implantable loop recorder, a device for detecting cardiac arrhythmias. A 65-year-old man was referred to our hospital for loss of consciousness with myotonic jerks during sleep. He had experienced several similar episodes. No family history of sudden death was evident, and no structural heart disease was present. Coronary angiography with intracoronary acetylcholine (ACh) showed neither organic stenosis nor vasospastic angina. Ventricular tachyarrhythmias were not induced by programmed electrical stimuli. Sleep electroencephalography, brain magnetic resonance imaging and magnetic resonance angiography revealed no specific findings. We implanted a loop recorder to monitor rhythm abnormalities. One month later, an attack occurred at night. His wife recognized the episode and activated the implantable loop recorder. No arrhythmia was recorded, but myopotentials characteristic of tonic-clonic seizures were detected.

An iterative reconstruction algorithm for three-dimensional (3-D) microwave tomography by using time-domain microwave data is applied to detect breast tumor. A numeric breast model with randomly distributed glandular tissues (random size and permittivity) with a tu- mor is designed for the calculation of synthetic microwave data. An \air phantom" consisting of a section of polyvinyl chloride (PVC) pipe fllled with styrofoam and a thin glass cylinder is constructed for col- lecting microwave data in laboratory. The \breast" and \air phantom" are reconstructed. Reconstruction results show that the \tumor" in the

This paper discusses the reconstruction of the subsurface from radar data using a time-domain reconstruction method. Before the reconstruction is conducted, data preprocessing is carried out. The preprocessing transforms measured data transmitted and received by 3-D dipole antennas into equivalent data excited and received by 3-D ideal electric dipoles and, then, into equivalent data excited and received by 2-D ideal electric dipoles. Distributions of permittivity, conductivity, and permeability are reconstructed from the preprocessed data by a 2-D forward-backward time-stepping waveform inverse scattering technique. Two 2-D examples of permittivity and conductivity reconstruction from synthetic noisy and field borehole radar data are demonstrated to show the effectiveness of the proposed method

This paper introduces an example of real-time “big data” processing systems accelerated by field-programmable gate arrays (FPGAs), which will open up a novel design field for digital circuit engineers. Contrary to the perception that software on commodity servers dominates such large-scale processing requirements, there are various chances for utilizing hardware for the acceleration. One of the most promising applications is complex event processing (CEP), which requires hardware-based acceleration due to it having to process massive amounts of data in real time. We propose a design flow for compiling software-oriented event language into highly parallelized and pipelined CEP circuits, which enables our system to achieve a strikingly high performance of 20 Gbps. A sophisticated mechanism for integrating archives of previously arrived data with streams of current events also makes the FPGA-accelerated processing system applicable to a wide range of realistic “big data” applications.

Independent predictors of the severity of coronary atherosclerosis are ill defined. We sought to determine the predictors and examine the association of impaired glucose tolerance with stenosis severity. Four hundred thirty-seven patients were studied who underwent coronary angiography for suspected coronary artery disease. Serum concentrations of total cholesterol (TC), triglyceride (TG), high-density lipoprotein cholesterol (HDLc), lipoprotein(a) [Lp(a)] and apolipoproteins (Apo A-I and Apo B) were measured and low-density lipoprotein cholesterol (LDLc) concentration was calculated. Except the patients treated for diabetes mellitus (DM), patients were classified into three groups such as normal glucose tolerance (NGT), impaired glucose tolerance (IGT) and DM by glucose tolerance test. Coronary atherosclerosis index (CAI) representing the severity of coronary atherosclerosis was determined by summation of the stenosis score of all lesions on coronary angiograms. Results indicated that age, total amount of cigarettes smoked, Apo B/Apo A-I, and LDLc/HDLc correlated with CAI, whereas HDLc and Apo A-I concentrations inversely correlated with CAI. TC, TG, Lp(a), LDLc, Apo B concentrations and body mass index did not correlate with CAI. One- and two-hour plasma glucose concentrations and the area of plasma glucose concentration under the curve at the glucose tolerance test did not correlate with CAI, revealing that post-challenge glycemia is not associated with stenosis severity. CAI in IGT patients was significantly lower than that in DM patients but did not differ from that in NGT patients, indicating that IGT does not affect the stenosis severity. Multivariate analysis showed that age, male gender, Apo B/Apo A-I, DM, systemic hypertension, and total amount of cigarettes smoked were independent predictors of CAI.

We have proposed a time-domain forward-backward time-stepping (FBTS) method for reconstructing 3D structures in highly absorptive media. The reconstruction speed is greatly dependent on the number of transmitters. In this paper, we propose a source-group method to speed up the reconstruction. In the source-group method, multiple transmitters arranged at different positions are excited simultaneously, and receivers collect the wave fields. To compare the reconstruction results, three kinds of reconstructions from 16 conventional single transmitter-multiple receiver data sets, four source-group multiple-receiver data sets, and four conventional single-transmitter multiple-receiver data sets are carried out. Reconstruction by the source-group method is several times faster than (and the reconstructed results are almost the same as) those of the first kind of reconstruction, and they are much better than those of the third kind. © Wiley Periodicals, Inc. Microwave Opt Technol Lett 48: 67–71, 2006; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.21263

An iterative time-domain algorithm for reconstructing three-dimensional (3D) lossy objects using microwave data transmitted and collected by dipole antennas is presented. The electromagnetic and adjoint fields are calculated using the finite-difference time-domain (FDTD) method. Numerical examples show the algorithm can rebuild simultaneously from noise-free and noisy data the permittivity and conductivity of a 3D lossy object settled in a lossless background. © 2005 Wiley Periodicals, Inc. Microwave Opt Technol Lett 44: 238–243, 2005; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.20598

A two-dimensional (2D) time-domain inverse scattering technique for reconstructing lossy media is extended to three-dimensional (3D) cases. Forward and inversion algorithms of this approach are carried out by the finite-difference time-domain (FDTD) method. The reconstruction of a mine buried in soil illustrates that this method is one of useful techniques to detect buried mines. © 2003 Wiley Periodicals, Inc. Microwave Opt Technol Lett 39: 276–280, 2003; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.11189

As the volume of data that web services handle is becoming larger, many web service providers are utilizing memcached, an in-memory key-value store to improve their web server's performance. While memcached usually runs on a server with a high performance processor, various hardware platforms has been evaluated for running memcached in order to achieve higher performance. Recently, several works that use FPGAs have successfully achieved higher performance than Xeon. These works, however, struggles to utilize a large memory with FPGAs. In this paper, we propose a system that enables us to overcome this problem and enhances memcached by caching a part of software memcached's commands and data to the network interface card equipped with an FPGA and a DRAM. Our evaluation showed that the NIC cache has less than 30% of hit rate for workload with Latest key selection distribution, and 30% to 60% for Zipf distribution workloads.

Memcached is a technology that improves response speed of web servers by caching data on DRAMs in distributed servers. In order to achieve higher performance, memcached has been evaluated on various platforms. Among them, FPGA seems to be the most efficient platform to run memcached, and several research groups are trying to achieve higher throughput with it. However, it is difficult to utilize a large amount of memory (several dozen gigabytes) with an FPGA. Some groups are trying to solve this problem by using an embedded CPU for memory allocation and another group is employing an SSD. Unlike other approaches that try to replace memcached itself on FPGAs, our approach augments the software memcached running on the host CPU by caching its data and some operations at the FPGA-equipped network interface card (NIC) mounted on the server. The locality of memcached data enables the FPGA NIC to have a fairly high hit rate with a smaller memory. We first explore the cache parameters by software simulations and estimate the effectiveness of our approach, and then prototype a system to prove its effectiveness. Through our evaluation with YCSB, a standard key-value store (KVS) benchmarking tool, we estimate that the latency improved by an order of magnitude over software memcached running on a high performance CPU.

A critical source of information in automated trading is provided by market data feeds from financial exchanges. Two identical feeds, known as the A and B feeds, are used in reducing message loss. This paper presents a reconfigurable acceleration approach to A/B arbitration, operating at the network level, and supporting any messaging protocol. The key challenges are: providing efficient, low latency operations; supporting any market data protocol; and meeting the requirements of downstream applications. To facilitate a range of downstream applications, one windowing mode prioritising low latency, and three dynamically configurable windowing methods prioritising high reliability are provided. We implement a new low latency, high throughput architecture and compare the performance of the NASDAQ TotalView-ITCH, OPRA and ARCA market data feed protocols using a Xilinx Virtex-6 FPGA. The most resource intensive protocol, TotalView-ITCH, is also implemented in a Xilinx Virtex-5 FPGA within a network interface card. We offer latencies 10 times lower than an FPGA-based commercial design and 4.1 times lower than the hardware-accelerated IBM PowerEN processor, with throughputs more than double the required 10Gbps line rate.

A time-domain inverse scattering approach using time-reversed fields for reconstructing electrical parameters of cylindrical objects has been proposed in a previous work. The approach does not require the explicit knowledge of incident fields illuminating the object. The cost functional represented in terms of the time-reversed fields was minimized by a genetic algorithm (GA). In this paper, we propose a gradient-based minimization for reconstruction of an inhomogeneous object for which GA can not be applied due to computational complexity. The time-reversed fields are calculated by time-reversing the equivalent current sources determined by the total fields recorded on a measurement line. Numerical simulations are carried out to show the effectiveness of the proposed method., 8th European Conference on Antennas and Propagation, EuCAP 2014; The Hague; Netherlands; 6 April 2014 through 11 April 2014, Antennas and Propagation (EuCAP), 2014 8th European Conference on, pp.1334-1338; 2014

This presentation discusses on the comparison between "Reconfigurable Chip with High Level Synthesis" and "CPU, GPCPU with compiler such as CUDA" from the compiler perspective. Initially, we introduce several demands for acceleration with FPGA to achieve low latency calculation and control. As an application example, we show a High Frequency Trading. We accelerate it by FPGA NIC with C-based and SQL-based HLS, and show the necessity of high level language customizable reconfigurable chip. Then, we illustrate the difference of FPGA and processor (CPU, GPGPU) with the "FSM+Datapath" model and examine how the architecture difference affects delay and parallelism of operations. Next, we discuss parallelization of operations, threads with High Level Synthesis for FPGA and software compiler for processors. The main advantage of the former method is it is able to parallelize operations beyond control dependencies while the latter method has to obey control dependencies. Finally, some experimental results prove that "FPGA and HLS" generate better performance than a processor for control intensive algorithm.

The authors describe a coronary artery fistula complicated balloon angioplasty. The proximal left anterior descending coronary artery was dilated, but a septal branch was occluded by thrombus. Angioplasty was used on the septal branch, but a pseudoaneurysm communicating with the left ventricle occurred. Follow-up angiography revealed spon taneous closure of the fistula.