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TJ-II stellarator results on modelling and validation of plasma flow asymmetries due to on-surface potential variations, plasma fuelling physics, Alfvén eigenmodes (AEs) control and stability, the interplay between turbulence and neoclassical (NC) mechanisms and liquid metals are reported. Regarding the validation of the neoclassically predicted potential asymmetries, its impact on the radial electric field along the flux surface has been successfully validated against Doppler reflectometry measurements. Research on the physics and modelling of plasma core fuelling with pellets and tracer encapsulated solid pellet injection has shown that, although post-injection particle radial redistributions can be understood qualitatively from NC mechanisms, turbulence and fluctuations are strongly affected during the ablation process. Advanced analysis tools based on transfer entropy have shown that radial electric fields do not only affect the radial turbulence correlation length but are also capable of reducing the propagation of turbulence from the edge into the scrape-off layer. Direct experimental observation of long range correlated structures show that zonal flow structures are ubiquitous in the whole plasma cross-section in the TJ-II stellarator. Alfvénic activity control strategies using ECRH and ECCD as well as the relation between zonal structures and AEs are reported. Finally, the behaviour of liquid metals exposed to hot and cold plasmas in a capillary porous system container was investigated.

It has been previously documented that the main features and sensing performance of electrograms (EGMs) recorded in implantable cardioverter defibrillators (ICDs) depend on lead configuration. Although this dependence has been ascribed to differences in lead sensitivity and spatial resolution, the quantification of these two properties on ICD has not yet been attempted. In this paper, an operative framework to study the spatial resolution of ICD transvenous leads is presented. We propose to quantify the spatial resolution of ICD transvenous leads based on a new characterization called lead resolution volume (ResV). We analyzed the sensitivity distribution and the ResV of two unipolar (tip-can and coil-can ) and two bipolar (true or tip-ring and integrated or tip-coil) ICD transvenous lead configurations. A detailed 3-D model of the human thorax based on the visible human man dataset was used to compute the lead sensitivity and computer simulations of simple cardiac dynamics were used to quantify the ResV. Differences in the sensitivity distribution throughout the ventricular myocardium (VM) were observed for each lead configuration. In our computer model of the human thorax, the ResV was found to comprise 7%, 35%, 45%, and 70% of the VM for true bipolar, integrated bipolar, tip-can unipolar, and coil-can unipolar ICD leads, respectively. Furthermore, our analysis shows that the spatial resolution depends on both lead sensitivity and cardiac dynamics, and therefore, it can vary for different heart rhythms.

Emerging applications involving low-cost wireless sensor networks motivate well optimization of multi-user orthogonal frequency-division multiple access (OFDMA) in the power-limited regime. In this context, the present paper relies on limited-rate feedback (LRF) sent from the access point to terminals to minimize the total average transmit-power under individual average rate and error probability constraints. Along with the characterization of optimal bit, power and subcarrier allocation policies based on LRF, suboptimal yet simple schemes are developed for channel quantization. The novel algorithms proceed in two phases: (i) an off-line phase to construct the channel quantizer as well as the rate and power codebooks with moderate complexity; and (ii) an on-line phase to obtain, based on quantized channel state information, the optimum, rate, power and user-subcarrier allocation with linear complexity. Numerical examples corroborate the analytical claims and reveal that significant power savings result even with suboptimal schemes based on practically affordable LRF. The work in this paper was supported by the US ARL under the CTA Program, Cooperative Agreement No. DAAD19-01-2-0011; by USDoD ARO grant No. W911NF-05-1-0283; by Spanish Government grant No. TEC2005-06766-C03-01/TCM, and by the Government of C.A. Madrid grant No. P-TIC-000223-0505. Teoría de la Señal y Comunicaciones

Objective The aim of this study is to describe the phenotype of 4 Spanish patients and the finding of a novel mutation in TK2 gene. Methods We report 4 unrelated male patients from non-consanguineous families. Details of the clinically features, biochemical, anatomy pathology and genetic findings are presented. Results 3/4 showed a similar phenotype with normal early development until a progressive hypotonia and muscular weakness with a fast motor regression started between 14 and 24 months old. The other patient showed a mild late onset phenotype, starting the clinical symptoms at 4 years old with facial and hand-feet distal muscle weakness. Currently he is able to walk independently with severe hyperlordosis, facial and scapular muscle weakness. All patients presented a mild increase of serum CK and lactate levels. Electromyography showed a myopathy pattern. Muscle biopsy showed dystrophic features and COX negative fibres, lipid vacuoles and ragged red fibres (RRF) in 4/4 patients, but the patient with the mild-late onset phenotype had a less severe pattern. Genetic studies showed more than 80% of depletion in mtDNA in the muscles of all of them. The one with late-onset mild phenotype showed a less reduced percentage of depletion in mtDNA in muscle (50–60%). Sequence analysis of the TK2 gene found two heterozygous pathogenic mutations as previously described in the literature. A novel mutation (c.623A>G; p.Tyr208Cys) was found in one patient with a significant reduction of TK2 activity studied in fibroblast. Conclusion Severe and fast progressive muscle weakness in early childhood should lead the clinicians to search for evidence of mitochondria dysfunction and alert about a possible TK2 deficiency diagnosis. The new approach with dTMP–dCMP in early stages of this disorder should be considered.

The efficiency of multi-access communications over wireless fading links benefits from channel-adaptive allocation of the available bandwidth and power resources. Different from most existing approaches that allocate resources based on perfect channel state information (P-CSI), this work optimizes channel scheduling and resource allocation over orthogonal fading channels when user terminals and the scheduler rely on quantized channel state information (Q-CSI). The novel unifying approach optimizes an average transmit-performance criterion subject to average quality of service requirements. The resultant optimal policy per fading realization either allocates the entire channel to a single (winner) user, or, to a small group of winner users whose percentage of shared resources is found by solving a linear program. Both alternatives become possible by smoothing the allocation scheme. The smooth policy is asymptotically optimal and incurs reduced computational complexity.

Emerging applications involving low-cost wireless sensor networks motivate well optimization of multi-user orthogonal frequency-division multiple access (OFDMA) in the power-limited regime. In this context, the present paper relies on limited- rate feedback (LRF) sent from the access point to terminals to acquire quantized channel state information (CSI) in order to minimize the total average transmit-power under individual average rate and error probability constraints. Specifically, we introduce two suboptimal reduced-complexity schemes to: (i) allocate power, rate and subcarriers across users; and (ii) design accordingly the channel quantizer. The latter relies on the solution of (i) to design equally probable quantization regions per subcarrier and user. Numerical examples corroborate the analytical claims and reveal that the power savings achieved by our reduced-complexity LRF designs are close to those achieved by the optimal solution.

In nonpregnant rats, po administration of NTA with cadmium chloride reduces the mortality of cadmium administered po as 64 and 80 mg/kg cadmium chloride alone. NTA with cadmium chloride also prevents the marked weight loss observed with administration of cadmium chloride alone. NTA enhances urinary and fecal excretion of cadmium when administered po with cadmium chloride as compared with the urinary and fecal excretion of cadmium chloride alone. Finally, cadmium analyses of liver, kidney and muscle reveal NTA inhibits the deposition of cadmium in these tissues when administered po with cadmium chloride. It is concluded that NTA exerts a protective effect against the toxicity of cadmium chloride and enhances excretion of the metal which inhibits organ and tissue deposition of cadmium.