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The physics requirements of the heating and current (H&CD) systems in a Demonstration Fusion Power Plant (DEMO) are often beyond the actual level of design maturity and technology readiness required. The recent EU fusion roadmap advocates a pragmatic approach and favours, for the initial design integration studies, systems to be as much as possible, extrapolated from the ITER experience. To reach the goal of demonstrating the production of electricity in DEMO with a closed fuel cycle by 2050, one must ensure reliability, availability, maintainability, inspectability (RAMI) as well as performance, efficiency and optimized design for the H&CD systems. In the recent Power Plant Physics & Technology (PPP&T) Work Programme, a number of H&CD studies were performed. The four H&CD systems Neutral Beam (NB) Injection, Electron Cyclotron (EC), Ion Cyclotron (IC) and Lower Hybrid (LH) were considered. First, a physics optimization study was made assuming all technologies are available and identifying which parameters are needed to optimize the performance for given plasma parameters. Separately, the (i) technological maturity was considered (e.g. 240 GHz gyrotrons for EC) and (ii) technologies were adapted (e.g. multi-stage depressed collector for EC) or (iii) novel solutions (e.g. photo-neutralization for NB or new antennae concepts for IC) were studied to overcome the limitations of the present H&CD systems with respect to DEMO requirements. Further constraints imposed by remote maintenance or breeding blanket interactions were considered. [ABSTRACT FROM AUTHOR]

Abstract: Percutaneous coronary intervention (PCI) of small coronary vessels represents a real challenge for myocardial revascularization because of the high risk of stent-restenosis and increased risk of adverse clinical events. Moreover, small coronary arteries supply small myocardial territories therefore questioning the clinical significance of small-vessel stenoses. The definition of small-vessel disease and PCI-strategies used are very heterogeneous across studies. The present review will focus on percutaneous coronary revascularization in patients with small vessel coronary artery disease. [Copyright &y& Elsevier]

BACKGROUND: Beta2-adrenergic receptor Thr164Ile (threonine (Thr) is replaced by an isoleucine (Ile) at codon 164) polymorphism was postulated to contribute to lower exercise tolerance and poor prognosis in patients with congestive heart failure. However, heart failure is associated with several abnormalities of beta receptor signalling, and underlying mechanisms are not clear. OBJECTIVES: To investigate whether Thr164Ile polymorphism negatively modulates myocardial contractile performance and is associated with adverse long-term prognosis of patients with congestive heart failure. METHODS: Among 55 subjects, cardiac contractile response to the beta2-adrenergic receptor agonist terbutaline was assessed from the peak myocardial velocity of systolic shortening (Sm) in 18 subjects with the Ile-164 variant and 37 matched controls. In total, 24 subjects had normal left ventricular (LV) function and 31 presented with congestive heart failure due to idiopathic dilated cardiomyopathy. RESULTS: In patients with normal LV function, peak terbutaline-induced increase (Delta) in Sm was lower in subjects with the Ile-164 variant than in controls (Delta33% (4%) vs Delta56% (4%), p<0.01). In patients with heart failure, subjects with Ile-164 showed further severe reduction of beta2-adrenergic-mediated increase in Sm as compared with controls with heart failure (Delta20% (5%) vs Delta39% (4%), p<0.05). Patients with heart failure with Ile-164 showed a severely blunted force-frequency relationship in response to agonist stimulation. At 2-years of follow-up, patients with heart failure with the Ile-164 variant showed higher incidence of adverse events than controls with heart failure (75% (6/8)] vs 30% (7/23), p<0.05). CONCLUSIONS: The beta2-adrenergic Thr164Ile polymorphism directly modulates adrenergic-mediated cardiac responses in patients with normal and failing myocardium. Furthermore, blunted beta2 adrenergic-mediated myocardial contractile response in patients with Ile-164 variant seems to adversely modulate the course of congestive heart failure. [ABSTRACT FROM AUTHOR]

27 kDa Heat shock protein (Hsp27), which is also identified as p29 estrogen-receptor associated protein, plays a crucial role in specific growth stages. It also seems to be involved in the balance between differentiation and apoptosis. To determine whether Hsp27 is involved during craniofacial development and odontogenesis, its expression was studied through immunohistochemistry of developing jaw bone as well as the odontogenesis of heads from human fetuses. Formalin-fixed paraffin-embedded specimens of 7 human fetuses (3 female, 4 male), obtained from miscarriages occurring between the 9th and 16th weeks of pregnancy, were examined by using a monoclonal antibody against Hsp27. Staining intensity (weak, +; moderate, ++; strong, +++) was evaluated semiquantitatively. The sample slice was cut through a coronal plane, which included eyes, nasal cavities, tongue, and primitive dental lamina with tooth germs. A transient and spatially restricted expression of Hsp27 in developing human jaw bones and teeth was observed. Osteoblasts around the uncalcified bone matrix showed Hsp27 immunoreaction products (+++), whereas osteocytes were not immunolabeled. In mandibular condyle, immunolabeling was restricted to hypertrophic chondrocytes (++). In developing tooth germs, Hsp27 immunostaining was detected throughout the bud (+++). At the early cap stage, a strong immunolabeling for Hsp27 was seen in the dental lamina (+++), and a moderate staining was seen in the outer dental epithelium (++). At the late cap stage, Hsp27 expression was detected in the outer dental epithelium (++) as well as in the cells of the future stellate reticulum (++). The spatiotemporal-restricted expression of Hsp27 in craniofacial bones during development suggests that this protein could be involved in the balance between differentiation and apoptosis, by modulating the viability of osteoblasts and chondrocytes. The specific regional and temporal expression patterns of Hsp27 during tooth development sustains that this small Hsp might be related to the morphogenesis and cytodifferentiation processes of tooth germs. [ABSTRACT FROM AUTHOR]

Toroidal geometry affects the evolution of k|| (the component of the wave vector parallel to the magnetic field) along the lower hybrid, (LH) wave trajectories. In this paper such variations are investigated both analytically and numerically. The main parameters governing this phenomenon are found and how k|| upshift can occur within this scheme is elucidated. As a figure of merit a k||- upshift factor is defined and discussed in a dimensionless parameter space in which all the LH experiments can be represented. Finally, a discussion of whether and when toroidal effects can fill the gap between the high phase velocity of the injected LH waves and the electron thermal velocity is presented by analyzing different experimental situations. [ABSTRACT FROM AUTHOR]

Percutaneous coronary interventions (PCI) in calcified coronary artery lesions are associated with impaired stent expansion, higher rate of periprocedural complications and cardiac mortality. Lesion preparation using calcium modifying techniques such as Rotational Atherectomy (RA) or Intravascular Lithotripsy (IVL) has been advocated. Studies comparing these technologies are lacking. We aimed to compare in-stent pressure gradients, evaluated by vessel fractional flow reserve (vFFR), in calcific lesions treated using either RA or IVL. Patients undergoing either RA- or IVL-assisted PCI from two European centers were included. Propensity score matching (1:2) was performed to control for potential bias. Primary outcome was post-PCI in-stent pressure gradients calculated by vFFR (vFFRgrad). Secondary outcomes included the proportion of patients with complete functional revascularization defined as distal vFFR post-PCI (vFFRpost) ≥ 0.90. From a cohort of 210 patients, 105 matched patients (70 RA and 35 IVL) were included. Pre-PCI vFFR did not differ between groups (0.65 ± 0.13 RA and 0.67 ± 0.11 IVL). After PCI, in-stent pressure gradients were significantly lower in the IVL group (0.032 ± 0.026 vs 0.043 ± 0.026 in the RA group, p = 0.024). The proportions of vessels with functional complete revascularization was similar between the two groups (32.9% vs. 37.1% in the RA and IVL group, respectively; p = 0.669). Calcific lesions preparation with IVL is effective and resulted in lower in-stent pressure gradients compared to RA. Approximately one third of the patients undergoing PCI for a severely calcified lesion achieved functional revascularization with no difference between rotational RA and IVL. [Display omitted] • Severe calcifications have been linked with poor prognosis following percutaneous coronary intervention, mainly due to impaired stent expansion. • A novel tool, intravascular lithotripsy (IVL), employs pressure waves from lithotripsy emitters to fragment selectively calcium plaques sparing soft tissues. • Patients treated with intravascular lithotripsy had significantly lower post-PCI trans-lesional pressure gradients compared to those treated with rotational atherectomy. [ABSTRACT FROM AUTHOR]

Lower-hybrid (LH) wave propagation is studied for a general magnetic-field configuration. The ray-tracing equations in the geometric optics approximation are analytically and numerically solved in flux surface coordinates by using asymptotic techniques. In particular, the effects of elongation, triangularity, and the Shafranov shift on wave penetration are pointed out. Numerical applications devoted to the study of current drive generation for the International Thermonuclear Experimental Reactor (ITER) [Nucl. Fusion 31, 1135 (1991)] plasma parameters will also be presented. [ABSTRACT FROM AUTHOR]

Diagnosis of heart failure with preserved ejection fraction (HFpEF) in patients with dyspnea and paroxysmal atrial fibrillation (AF) is challenging. Speckle tracking-derived left atrial strain (LAS) provides an accurate estimate of left ventricular (LV) filling pressures and left atrial (LA) phasic function. However, data on clinical utility of LAS in patients with dyspnea and AF are scarce. To assess relationship between the LAS and the probability of HFpEF in patients with dyspnea and paroxysmal AF. The study included 205 consecutive patients (62 ± 10 years, 58% males) with dyspnea (NYHA≥II), paroxysmal AF and preserved LV ejection fraction (≥50%), who underwent speckle tracking echocardiography during sinus rhythm. Probability of HFpEF was estimated using H 2 FPEF and HFA-PEFF scores, which combine clinical characteristics, echocardiographic parameters and natriuretic peptides. Patients with high probability of HFpEF were significantly older, had higher body mass index, NT-proBNP, E/e', pulmonary artery pressure and larger LA volume index than patients in low-to-intermediate probability groups (all p < 0.05). All components of LAS and LA strain rate showed proportional impairment with increasing probability of HFpEF (all p < 0.05). Out of the speckle tracking-derived parameters, reservoir LAS showed the largest area under the curve (AUC = 0.78, p < 0.001) and the strongest independent predictive value (OR: 1.22, 95% CI 1.08–1.38) to identify patients with high probability of HFpEF. Reservoir LAS shows a high diagnostic performance to distinguish HFpEF from non-cardiac causes of dyspnea in symptomatic patients with paroxysmal AF. • LA strain showed to be a useful index to diagnose HFpEF in patients with history of AF. • LA strain might provide additional clue for diagnosing HFpEF in patients with intermediate probability of HFpEF. • Monitoring atrial function in this clinical setting might provide useful prognostic information. [ABSTRACT FROM AUTHOR]

Background: We hypothesized that fractional flow reserve (FFR)-guided percutaneous coronary intervention (PCI) would be superior to medical therapy as initial treatment in patients with stable coronary artery disease.Methods: Among 1220 patients with angiographically significant stenoses, those in whom at least one stenosis was hemodynamically significant (FFR, ≤0.80) were randomly assigned to FFR-guided PCI plus medical therapy or to medical therapy alone. Patients in whom all stenoses had an FFR of more than 0.80 received medical therapy and were entered into a registry. The primary end point was a composite of death, myocardial infarction, or urgent revascularization.Results: A total of 888 patients underwent randomization (447 patients in the PCI group and 441 in the medical-therapy group). At 5 years, the rate of the primary end point was lower in the PCI group than in the medical-therapy group (13.9% vs. 27.0%; hazard ratio, 0.46; 95% confidence interval [CI], 0.34 to 0.63; P<0.001). The difference was driven by urgent revascularizations, which occurred in 6.3% of the patients in the PCI group as compared with 21.1% of those in the medical-therapy group (hazard ratio, 0.27; 95% CI, 0.18 to 0.41). There were no significant differences between the PCI group and the medical-therapy group in the rates of death (5.1% and 5.2%, respectively; hazard ratio, 0.98; 95% CI, 0.55 to 1.75) or myocardial infarction (8.1% and 12.0%; hazard ratio, 0.66; 95% CI, 0.43 to 1.00). There was no significant difference in the rate of the primary end point between the PCI group and the registry cohort (13.9% and 15.7%, respectively; hazard ratio, 0.88; 95% CI, 0.55 to 1.39). Relief from angina was more pronounced after PCI than after medical therapy.Conclusions: In patients with stable coronary artery disease, an initial FFR-guided PCI strategy was associated with a significantly lower rate of the primary composite end point of death, myocardial infarction, or urgent revascularization at 5 years than medical therapy alone. Patients without hemodynamically significant stenoses had a favorable long-term outcome with medical therapy alone. (Funded by St. Jude Medical and others; FAME 2 ClinicalTrials.gov number, NCT01132495 .). [ABSTRACT FROM AUTHOR]

Acromegaly is a rare acquired endocrine disorder linked to hypersecretion of the growth hormone, which induces a progressive somatic disfigurement on the face and on the limbs. Changes in the craniomaxillofacial complex are one of the main indicators of the disease and are therefore a key feature for an early diagnosis. This article, after a short introduction on the ossification processes involved, describes the main modifications of the craniofacial complex induced by acromegaly on both hard and soft tissues. The most relevant odontostomatological aspects of the disease are then discussed, together with the important role of the dentist/orthodontist in its early diagnosis and treatment. [ABSTRACT FROM AUTHOR]

Since the 2010 IAEA-FEC Conference, FTU has exploited improvements in cleaning procedures and in the density control system to complete a systematic exploration of access to high-density conditions in a wide range of plasma currents and magnetic fields. The line-averaged densities at the disruptive limit increased more than linearly with the toroidal field, while no dependence on plasma current was found; in fact, the maximum density of 4.3 × 1020 m−3 was reached at B = 8 T even at the minimum current of 0.5 MA, corresponding to twice the Greenwald limit. The lack of plasma current dependence was due to the increase in density peaking with the safety factor. Experiments with the 140 GHz electron cyclotron resonance heating (ECRH) system were focused on the sawtooth (ST) period control and on the commissioning of a new launcher with real-time steering capability that will act as the front-end actuator of a real-time system for ST period control and tearing mode stabilization. Various ECRH and electron cyclotron current-drive modulation schemes were used; with the fastest one, the ST period synchronized with an 8 ms modulation period. The observed period variations were simulated using the JETTO code with a critical shear model for the crash trigger. The new launcher was of the plug-in type, allowing quick insertion and connection to the transmission line. Both beam characteristics and steering speed were in line with design expectation. Experimental results on the connection between improved coupling of lower hybrid waves in high-density plasmas and reduced wave spectral broadening were interpreted by fully kinetic, non-linear model calculations. A dual-frequency, time-of-flight diagnostic for the measurement of density profiles was developed and successfully tested. Fishbone-like instabilities driven by energetic electrons were simulated by the hybrid MHD-gyrokinetic XHMGC code. [ABSTRACT FROM AUTHOR]

A numerical model for predictive simulations of radiofrequency current drive in magnetically confined plasmas is developed. It includes the minimum requirements for a self-consistent description of such regimes, i.e., a three-dimensional kinetic equation for the electron distribution function, one-dimensional heat and current transport equations, and resonant coupling between velocity space and configuration space dynamics, through suitable wave propagation equations. The model finds its full application in predictive studies of complex current profile control scenarios in tokamaks, aiming at the establishment of internal transport barriers by the simultaneous use of various radiofrequency current drive methods. The basic properties of this nonlinear numerical system are investigated and illustrated by simulations applied to reversed magnetic shear regimes obtained by Lower Hybrid and Electron Cyclotron current drive for parameters typical of the Tore Supra tokamak [Equipe Tore Supra, in Proceedings of the 12th International Conference on Plasma Physics and Controlled Nuclear Fusion Research, Nice, France, 1988 (International Atomic Energy Agency, Vienna, 1989), Vol. 1, p. 9]. © 2000 American Institute of Physics. [ABSTRACT FROM AUTHOR]

A direct, continuous, and independent association between blood pressure values and incidence of coronary artery disease has been well documented. However, the evidence that the reduction of blood pressure alone is not able to completely reverse the increase in the risk of coronary artery disease associated with essential hypertension suggests that the link between hypertension and coronary artery disease is a complex process including other factors beside the increase in blood pressure values. In this regard, the main determinant of coronary artery disease in hypertensive patients seems to be the development of left ventricular hypertrophy (LVH). In fact, hypertensive patients who died from sudden cardiac death showed a lesser degree of coronary atherosclerosis compared with normotensives, but a higher incidence of LVH. Several mechanisms can account for the increased coronary risk with LVH, including (1) an increase in left ventricular (LV) mass, which by itself requires more oxygen for tissue perfusion; (2) impairment of coronary flow reserve; (3) perivascular fibrosis, which then impairs oxygen supply to the myocardium; and (4) deterioration of LV diastolic function, which hampers myocardial perfusion. Recently, a study reported an impairment of endothelial function and abnormal control of the sympathetic tone in hypertensive patients, which may contribute to the risk of coronary artery disease. In particular, the impaired endothelial function resulting in a prevalence of vasoconstrictive, thrombogenic, and proliferative factors may account for the enhanced ischemic susceptibility of these patients. Furthermore, the cardiac adrenergic system plays an important role in regulating myocardial blood flow. On one hand, hypertensive patients show an exaggerated sympathetic response to physiologic stimuli, whereas on the other hand, the beta-adrenergic receptor-mediated vasodilating component of the sympathetic response is blunted in hypertension. Finally, excess body weight, dyslipidemia, glucose intolerance, and hyperinsulinemia, which are frequently interrelated, represent independent predictors of both coronary artery disease and hypertension. [ABSTRACT FROM AUTHOR]

Background: In the setting of primary percutaneous coronary intervention, patients with a chronic total occlusion in a non-infarct related artery were recently identified as a high-risk subgroup. It is unclear whether ST-elevation myocardial infarction patients with a chronic total occlusion in a non-infarct related artery should undergo additional percutaneous coronary intervention of the chronic total occlusion on top of optimal medical therapy shortly after primary percutaneous coronary intervention. Possible beneficial effects include reduction in adverse left ventricular remodeling and preservation of global left ventricular function and improved clinical outcome during future coronary events.Methods/design: The Evaluating Xience V and left ventricular function in Percutaneous coronary intervention on occLusiOns afteR ST-Elevation myocardial infarction (EXPLORE) trial is a randomized, prospective, multicenter, two-arm trial with blinded evaluation of endpoints. Three hundred patients after primary percutaneous coronary intervention for ST-elevation myocardial infarction with a chronic total occlusion in a non-infarct related artery are randomized to either elective percutaneous coronary intervention of the chronic total occlusion within seven days or standard medical treatment. When assigned to the invasive arm, an everolimus-eluting coronary stent is used. Primary endpoints are left ventricular ejection fraction and left ventricular end-diastolic volume assessed by cardiac Magnetic Resonance Imaging at four months. Clinical follow-up will continue until five years.Discussion: The ongoing EXPLORE trial is the first randomized clinical trial powered to investigate whether recanalization of a chronic total occlusion in a non-infarct related artery after primary percutaneous coronary intervention for ST-elevation myocardial infarction results in a better preserved residual left ventricular ejection fraction, reduced end-diastolic volume and enhanced clinical outcome.Trial Registration: trialregister.nl NTR1108. [ABSTRACT FROM AUTHOR]