P2Y11 Agonism Prevents Hypoxia/Reoxygenation- and Angiotensin II-Induced Vascular Dysfunction and Intimal Hyperplasia Development

Vascular dysfunction in cardiovascular diseases includes vasomotor response impairments, endothelial cells (ECs) activation, and smooth muscle cells (SMCs) proliferation and migration to the intima. This results in intimal hyperplasia and vessel failure. We previously reported that activation of the P2Y11 receptor (P2Y11R) in human dendritic cells, cardiofibroblasts and cardiomyocytes was protective against hypoxia/reoxygenation (HR) lesions. In this study, we investigated the role of P2Y11R signaling in vascular dysfunction. P2Y11R activity was modulated using its pharmacological agonist NF546 and antagonist NF340. Rat aortic rings were exposed to angiotensin II (AngII) and evaluated for their vasomotor response. The P2Y11R agonist NF546 reduced AngII-induced vascular dysfunction by promoting EC-dependent vasorelaxation, through an increased nitric oxide (NO) bioavailability and reduced AngII-induced H₂O₂ release; these effects were prevented by the use of the P2Y11R antagonist NF340. Human vascular SMCs and ECs were subjected to AngII or H/R simulation in vitro. P2Y11R agonist modulated vasoactive factors in human ECs, that is, endothelial nitric oxide synthase (eNOS) and endothelin-1, reduced SMC proliferation and prevented the switch towards a synthetic phenotype. H/R and AngII increased ECs secretome-induced SMC proliferation, an effect prevented by P2Y11R activation. Thus, our data suggest that P2Y11R activation may protect blood vessels from HR-/AngII-induced injury and reduce vascular dysfunctions. These results open the way for new vasculoprotective interventions.     

On the mechanism of bubble formation in a fluidized bed

A mechanism of bubble formation in a nonhomogeneous fluidized bed, based on instability theory, is suggested. In this mechanism it is assumed that the “bubbles” are formed at the bottom of the bed by the growth of prominences appearing because of the instability to perturbations of the lower surface of the bed. A bubble breaks off when the volume of the prominence becomes sufficiently large so that the buoyant force equals the sum of the bed resistance opposing its growth and the inertial forces. An equation for the diameter of the departing bubble is established.     

Performance comparison of local area video streaming systems

The performance of our Quality Oriented Adaptation Scheme (QOAS) for multimedia streaming in local networks is compared with other existing solutions (TFRCP, LDA+, and non-adaptive). This comparison is done in terms of bandwidth utilization, number of concurrent clients, loss rate, and end-user perceived quality. Simulation results show that for the same average end-user quality, our QOAS system can accommodate a significantly higher number of simultaneous clients while also having higher bandwidth utilization. For the same number of clients, the average end-user quality is always higher for QOAS than for the other solutions studied.     

Complete Parameter Identification of Large Induction Machines From No-Load Acceleration–Deceleration Tests

This paper introduces an offline deterministic method for identification of inertia moment, mechanical losses, and electrical parameters for large induction machines, based on direct-on-line starting and natural slowdown tests, performed under no-load conditions. The static characteristic of absorbed power is used for the validation of results. Complete experimental results for a 6-kV four-pole 7500-kW machine are presented. The method brings significant cost savings for testing large induction machines.     

Cell-Permeable Succinate Rescues Mitochondrial Respiration in Cellular Models of Statin Toxicity

Statins are the cornerstone of lipid-lowering therapy. Although generally well tolerated, statin-associated muscle symptoms (SAMS) represent the main reason for treatment discontinuation. Mitochondrial dysfunction of complex I has been implicated in the pathophysiology of SAMS. The present study proposed to assess the concentration-dependent ex vivo effects of three statins on mitochondrial respiration in viable human platelets and to investigate whether a cell-permeable prodrug of succinate (complex II substrate) can compensate for statin-induced mitochondrial dysfunction. Mitochondrial respiration was assessed by high-resolution respirometry in human platelets, acutely exposed to statins in the presence/absence of the prodrug NV118. Statins concentration-dependently inhibited mitochondrial respiration in both intact and permeabilized cells. Further, statins caused an increase in non-ATP generating oxygen consumption (uncoupling), severely limiting the OXPHOS coupling efficiency, a measure of the ATP generating capacity. Cerivastatin (commercially withdrawn due to muscle toxicity) displayed a similar inhibitory capacity compared with the widely prescribed and tolerable atorvastatin, but did not elicit direct complex I inhibition. NV118 increased succinate-supported mitochondrial oxygen consumption in atorvastatin/cerivastatin-exposed platelets leading to normalization of coupled (ATP generating) respiration. The results acquired in isolated human platelets were validated in a limited set of experiments using atorvastatin in HepG2 cells, reinforcing the generalizability of the findings.     

Strategic environmental assessment in Romania: between benefits and constraints

This paper offers an overall picture of the importance of Strategic Environmental Assessment (SEA) in Romania and its opportunities and constraints. The role, scope and effectiveness of SEA in Romania are presented in two good practice examples and examined in order to highlight the strengths and weaknesses of the procedure at national and local scale. In practice, the number of SEA procedures is very high due to the legislation in force, and it is increasingly effective in decision-making about programmes and plans. SEA can be viewed as a great opportunity for the implementation of sustainable development in practice. It also continues to be an important procedural and decisional instrument for management and monitoring of socioeconomic development, spatial planning and environmental protection in Romania.     

Performance evaluation of MADM-based methods for network selection in a multimedia wireless environment

Wireless Networks - As mobile devices have become more affordable, easy to use and powerful, the number of mobile users and their bandwidth demands have experienced a significant growth....     

Competition of several carbonation reactions in concrete: A parametric study

Carbonation caused by atmospheric carbon dioxide is one of the major physicochemical processes which can compromise the service life of reinforced concrete structures. While the bulk of the carbonation reaction is that of calcium hydroxide, other constituents of the porous matrix can also carbonate and compete with calcium hydroxide for carbon dioxide. Particularly the carbonation of calcium–silicate hydrates and unhydrated constituents are neglected by most authors in carbonation prediction models. In this paper, a mathematical model of carbonation is extended to include additional carbonation and hydration reactions. The competition of the several reactions and their effect on the carbonation depth is investigated by dimensional analysis and numerical simulations. A parameter study emphasises that multiple internal reaction layers appear. Their position and speed essentially depend on the strength of the different reactions. It is also observed that, for a wide range of parameters, the effect of some of the additional reactions on the carbonation depth is small. In particular, a comparison with data from laboratory experiments justifies the neglect of the carbonation of the unhydrated constituents in prediction models.     

Photoluminescence of ZnGa<Subscript>2</Subscript>O<Subscript>4</Subscript> doped with Mn,Yb, Sm,and Tb

ZnGa₂O₄ samples doped with Mn, Yb, Sm, and Tb have been prepared by a ceramic processing technique, and their 20°C photoluminescence spectra were measured. The results demonstrate that the four dopants have a significant effect on the photoluminescence of ZnGa₂O₄. Doping with Mn and Yb allows the peaks in the red spectral region to remain narrow and increases the PL intensity.     

Hyporeactivity of neonatal platelets is not caused by preactivation during birth

Little information exists concerning platelet function in neonates due to the small blood volume. Most studies using conventional aggregation methods have shown a diminished response to various agonists. This is in contrast to the lack of a bleeding tendency and to a short bleeding time in healthy neonates. In previous work we have shown that in healthy term neonates even after an uncomplicated delivery signs of thrombin generation can be demonstrated. This activation of the clotting system may also lead to platelet activation in the neonate. We investigated by means of flow cytometry the expression of activation markers GMP 140 and GP 53 on the surface of neonatal platelets and GP 53 intracellularly by means of a newly developed assay. The expression of GMP 140 and of GP 53 after thrombin stimulation was significantly higher on adult rather than neonatal platelets, while there was no difference between neonatal and adult platelets using GP 53 as intracellular marker. In none of the healthy term neonates after an uncomplicated delivery were activated platelets demonstrated. CONCLUSION: Our data show that the decreased reactivity of neonatal platelets is not caused by preactivation during birth but rather represents a developmental phenomenon. Possibly the observed hyporeactivity of neonatal platelets to thrombin helps to prevent harmful effects of birth stress on the clotting system of neonates.