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Background Coronary artery ectasia (CAE) is a relatively frequent finding in patient with ST-elevation myocardial infarction (STEMI) who undergo emergent coronary angiography. However, the long-term outcome of STEMI patients with CAE as compared to Non-CAE has been poorly investigated. Purpose To compare the baseline features and outcome of patients with and without CAE in the clinical setting of STEMI. Methods All patients with STEMI who underwent emergent coronary angiography from January 2012 to December 2017 at our Institution were retrospectively enrolled. Baseline demographic, clinical, instrumental, angiographic and percutaneous coronary intervention (PCI) findings were collected for patients with and without CAE. The study outcome measures were recurrent myocardial infarction (MI) and all-cause death. The propensity score weighting (PSW) technique was used to take into account for potential selection bias in treatment assignment between CAE and Non-CAE groups. Results The study included 534 patients with STEMI (mean age 62.9±12.0 years), 154 were CAE and 380 Non-CAE. The two groups were significantly different in terms of sex (90.9% in CAE vs 72,6% in Non-CAE, p The survival free from recurrent MI was lower, although not statistically significant, in CAE vs. Non-CAE patients (3.1/100 person/years vs. 4.8/100 person/years; Log-Rank = 0.068). After PSW, an optimal balance was obtained as demonstrated by a standardized mean difference Conclusions Patient with STEMI and angiographic evidence of CAE have a different clinical profile compared to Non-CAE. In this analysis focused on STEMI patients, CAE was associated with a higher risk of recurrent MI at long-term follow-up. Funding Acknowledgement Type of funding source: None

Transmission of 86 dense wavelength division multiplexed channels on a 50-GHz grid, carrying 112-Gb/s radio-frequency-assisted dual-channel dual-polarization 16-QAM (8.6-Tb/s), was successfully demonstrated in a straight-line transmission link. Required bit-error rate before forward error correction was obtained after 1200 km of ultralow-loss G.652 fiber (0.17-dB/km attenuation) and after 881 km of conventional G.652 fiber (0.21-dB/km attenuation).

The authors propose a new research hypothesis about cancer pathology, starting from the hypothesis of considering cancer as a process of adaptation to changed conditions, which can be internal or external to the organism, with the aim of reaching the survival of the species. The authors, in the present work, put forward an hypothesis which is based on the observation of natural phenomenon, referred to the previously described mutations, some as natural evolutionary phenomena which are genetically transmitted as a result of environmental adaptation (for example the color of the skin), some others, with the same modalities, as pathological phenomena (for example thalassemia), some others as more flexible environmental responses (for example human height in relation with the improved food conditions), some others as immediate responses of the organism in order to defend its own biological integrity and individuality (for example violent anaphylactic reactions which happen as consequences of extraneous proteins

We theoretically and experimentally investigate the performance of erbium-doped fiber amplifier (EDFA)-based WDM ring networks with free amplified spontaneous emission (ASE) light recirculation. We show that, with proper network and amplifier design, the lasing light generated by free ASE recirculation within the looped network provides an effective gain clamping technique, ensuring limited signal power excursions under WDM channels add-drop operations. Considering a ring network composed of eight fiber sections and eight EDFAs, maximum signal power overshoots below 2.5dB have been measured under 23/24 WDM channels drop. Optical signal-to-noise ratio (OSNR) analysis and bit-error rate (BER) measurement at 10 Gb/s confirm acceptable performances and negligible penalties due to polarization effects and relative intensity noise transfer from laser light to WDM signals. We also propose and demonstrate a new link control technique which overcomes the main limiting factors of such networks, respectively, related to OSNR degradation, stability and survivability to fiber and EDFA breakages.

We describe a new method to determine the Er/sup 3+/-fiber gain coefficient using a dynamic gain tilt technique. The method is based on attenuation measurement, gain measurements and crossover optimization of dynamic gain tilt. Results demonstrate that this method is very simple, highly accurate and especially useful for extended band erbium doped fiber amplifiers (EDFAs) design.

We experimentally investigate dynamic bit-error rate (BER) performance impairments induced by add-drop operations in semiconductor-optical amplifer (SOA)-based wavelength-division-multiplexing (WDM) metro-ring networks. Link control techniques in short-medium span networks provide effective performance improvement and significant BER transient reduction during add-drop operation, with respect to SOA linear operating condition (low input signal power). This behavior is confirmed by dynamic BER measurements and optical signal-to-noise penalty analysis.

We experimentally study the performance of wavelength-division-multiplexing (WDM) metro/access ring networks, based on semiconductor optical amplifiers (SOAs), considering several gain control techniques. We show that gain control through link-control (LC) channel or amplified spontaneous emission (ASE) power recirculation, effectively used in erbium-doped fiber amplifier-based WDM ring networks, introduces serious penalties due to intensity noise transfer, and cannot be used in short-span SOA-based WDM rings. On the other hand, we observe a net benefit using LC channel and ASE extraction for short span rings and a limited WDM channel number, compared with linear operating conditions. An effective optical signal-to-noise ratio improvement of 2.1 dB has been achieved with LC channel extraction with respect to linear operation, for a 4 x 13.5 dB span ring with eight WDM channels. For spans longer than 15 dB, system performance in gain-controlled rings is found to be similar to noncontrolled ones.

A new broad-band amplifier topology that provides a continuous gain across 75 nm (1528-1603 nm) of optical bandwidth using Er/sup 3+/-doped SiO/sub 2/ fiber is demonstrated. The noise figure is low and does not present any discontinuity across the entire amplification bandwidth. The topology has a buried 1550/1585-nm splitter to reduce input signal loss and to provide amplified spontaneous emission suppression. The topology has been optimized using hybrid fiber; Er/sup 3+/-doped SiO/sub 2/ for the first stage and Er/sup 3+/-doped TeO/sub 2/ for the second stage, achieving 82 nm (1526-1618 nm) of optical bandwidth.

We present theoretical and experimental verification of an optimized erbium-doped fiber amplifiers model in the extended band with an emission coefficient derived from a dynamic gain tilt technique. The validity of the method has been verified with two different erbium fibers.

We propose a cost-effective implementation of reconfigurable add&drop functionality in Optical Cross Connects based on the concept of common add&drop in the node (OXC with per- Node Add&Drop, OXC-NAD). The proposed architecture constrains usable transponders wavelengths, but the analysis on significant mesh topologies demonstrates that this does not affect the behavior of the transparent networks. The OXC-NAD is shown to also significantly reduce the node cost irrespective of the nodal degree.

A simple and efficient gain control scheme for EDFA based reconfigurable OADM dedicated to metro applications is proposed. Each pair of input-output amplifiers is gain clamped by single control channel @ 1532 nm which bypasses the ROADM node structure.

A testbed implementation for 100 Gb/s Ethernet optical time division multiplexing experiments is described along with optical subsystems used in its implementation. Testbed potentialities relating to wavelength division multiplexing and hybrid wavelength/polarization division multiplexing implementations are also described. First experimental results at 20 Gb/s are carried out demonstrating a power penalty lower than 1 dB.

We demonstrate that a free ASE light re-circulation in EDFA based WDM ring networks provides an effective gain clamping technique. Proper network and amplifier design ensure signal power overshoots lower than 2.5 dB under 23/24 WDM channels add-drop operations.

We present results on spectral gain changes resulting from small changes of pump wavelength in erbium-doped fiber amplifiers (EDFAs). While conventional-band EDFAs exhibit a significant effect with 980-nm pumping and a smaller effect with 1480 nm, it is absent for extended-band EDFAs operating around 1585 nm.

A new method to determine the Er-fiber gain coefficient is presented using a dynamic gain tilt technique. Results demonstrate that this method is very simple, highly accurate, and especially useful for long-wavelength erbium-doped fiber amplifier.

We present results on the quantum efficiency of long wavelength erbium doped fibre amplifiers including the inpact of an idler signal and of 1480 nm counter-pumping. We report on a silica based long wavelength amplifier (LWEDFA) which uses a relatively short erbium fibre. The amplification characteristics are studied in terms of the quantum conversion efficiency (QCE) of a 980 nm co-pumped and 1480 nm counter-pumped device. The effect of an idler signal on efficiency has also been explored.

An improvement in amplifier efficiency resulting from pump wavelength tuning is shown to occur in extended band (L-band) EDFAs. We investigate the effects for different EDFA configurations and for 980 nm and 1480 nm pumping.

The propagation of equally and unequally spaced WDM optical signals through a cascade of praseodymium-doped fibre amplifiers and conventional single mode fibres with zero chromatic dispersion at 1300 nm is numerically analysed. We show that a proper choice of the amplifier characteristics, span length and channel allocation, combined with the use of gain equalising and grating filters, allows to maximize the transmission distance with a substantial reduction of gain peaking and four-wave mixing crosstalk.

This study focuses on the relationship between some aspects of intra-erythrocytic sodium metabolism (intra-erythrocytic Na content, Na,Li-countertransport), blood pressure, and family history of hypertension, in a group of 84 randomly selected school children (45 males, 39 females). Na,Li-countertransport was significantly related to both systolic blood pressure (SBP) and diastolic blood pressure (DBP) only in boys at the univariate level, but both of these associations lost statistical significance after the possible confounding role of weight and height were taken into consideration. In both sexes, participants with a family history of hypertension had similar values of both intra-erythrocytic Na content and Na,Li-countertransport to participants with no family history. We conclude that family history of hypertension does not seem to play an important role in the determination of either intra-erythrocytic Na content or Na,Li-countertransport at this age. Although the positive association between Na,Li-countertransport and blood pressure observed in adult males is already present in childhood, this probably is still, at least in part, dependent upon body size.

Exercise two-dimensional echocardiography (2D-ECHO) can be used to detect coronary artery disease in patients (pts) by the development of stress-induced transient asynergy in areas without wall motion abnormalities when at rest. The aim of the study is to verify the accuracy of exercise 2D-ECHO in the identification of high risk pts with multivessel disease after the first acute myocardial infarction (AMI). Technically adequate 2D-ECHO examinations were obtained in 21 of 28 (75%) consecutive patients after acute myocardial infarction. 30-50 days after acute myocardial infarction, these 21 pts (19 males and 2 females, mean age +/- SD = 54.3 +/- 8.7) underwent 2D-ECHO during bicycle exercise in supine position. The marker of multivessel disease was the development, during the stress test, of new areas of asynergy not adjacent to the infarcted area (i.e. transient remote asynergy). Two months after acute myocardial infarction all pts underwent coronary angiography to verify the severity of coronary obstruction (reduction of luminal diameter greater than or equal to 75% in the non infarct related vessel).(ABSTRACT TRUNCATED AT 250 WORDS)

The present study was designed to investigate whether non-insulin-dependent diabetic hypertensive patients exhibit abnormalities in intracellular sodium metabolism similar to those described for essential hypertensive patients. Both normotensive and hypertensive non-insulin-dependent diabetic patients had similar average values of both Na+-Li+ countertransport and Na+-K+ cotransport compared with nondiabetic controls. Within the group of diabetic patients, hypertensive patients did not exhibit any abnormalities in either of the sodium transport pathways studied. The possible implications of these findings are addressed.

The present report evaluates a method for the determination of the maximal velocity of the outward sodium, potassium, chlorine (Na-K-Cl) cotransport in erythrocytes. The loading procedure was carried out using the ionophore nystatin. The technical error for this assay, based on concurrent analysis of randomized blind duplicate samples, was 8.04% of the sample mean and 27.5% of the sample standard deviation. The assay was stable over time and reproducible. Fasting was not necessary. The ratio of intra- to interindividual variances was small. The cells can be safely preserved in an appropriate preservation solution without modification of the ion transport assay. The assay appears to be adequate for use in large-scale field trials.