Nonlocal transport in the charge density waves of oo-TaS3_3

We studied the nonlocal transport of a quasi-one dimensional conductor $o$-TaS$_3$. Electric transport phenomena in charge density waves include the thermally-excited quasiparticles, and collective motion of charge density waves (CDW). In spite of its long-range correlation, the collective motion of a CDW does not extend far beyond the electrodes, where phase slippage breaks the correlation. We found that nonlocal voltages appeared in the CDW of $o$-TaS$_3$, both below and above the threshold field for CDW sliding. The temperature dependence of the nonlocal voltage suggests that the observed nonlocal voltage originates from the CDW even below the threshold field. Moreover, our observation of nonlocal voltages in both the pinned and sliding states reveals the existence of a carrier with long-range correlation, in addition to sliding CDWs and thermally-excited quasiparticles.Comment: 8 pages, 4 figure

Research of nanocomposite structure of boron nitride at proton radiation

Using roentgen diffraction and electron microscopy, the influence of nanosecond irradiation by ion beams of high energy on forming of self-organized nanoblocks in near surface's layers of boron nitride (BN) has been studied. It was shown that low temperature transitions from hexagonal to wrutz boron nitrides is associated with changes of shape and sizes of self-organized particles consisting the nanoblocks. We have calculated the parameters of nanoblocks using the meanings of interplane distances and properties of subreflexes orders. The collective shifting deformations of layers in nanoblocks provides phase transition under the screen and forming the set of nanotubes with escaping of five order axes of symmetry. It has been realized that pentagons and stars arranged in points of entrance of five order axis of symmetry are associated with peculiarity of self-organization of the spiral-cyclic structures

Sorption properties of radiation-cross-linked polymer hydrogels containing ion-exchange fibers

Polymer hydrogel modification for soft contact lenses by ion-exchange fibers was studied in this work. The obtained results showed that the ion-exchange fiber modifiers have a number of advantages as compared with ion-exchange resin modifiers

Increase the strength characteristics of polymer films by radiation graft polymerization

The possibility of increasing the strength characteristics of polymer films based on polyethylene and polyamide by radiation graft polymerization was investigated. Two methods of graft polymerization (direct method and the method of polymer mixtures cross-linking) on the PMMA films surface were studied. The possibility of increasing the strength and elasticity of polymeric films by radiation modification of polymethyl methacrylate was shown

Convective Term and Transversely Driven Charge-Density Waves

We derive the convective terms in the damping which determine the structure of the moving charge-density wave (CDW), and study the effect of a current flowing transverse to conducting chains on the CDW dynamics along the chains. In contrast to a recent prediction we find that the effect is orders of magnitude smaller, and that contributions from transverse currents of electron- and hole-like quasiparticles to the force exerted on the CDW along the chains act in the opposite directions. We discuss recent experimental verification of the effect and demonstrate experimentally that geometry effects might mimic the transverse current effect.Comment: RevTeX, 9 pages, 1 figure, accepted for publications in PR

Coupling of the lattice and superlattice deformations and hysteresis in thermal expansion for the quasi one-dimensional conductor TaS3_3

An original interferometer-based setup for measurements of length of needle-like samples is developed, and thermal expansion of o-TaS$_3$ crystals is studied. Below the Peierls transition the temperature hysteresis of length $L$ is observed, the width of the hysteresis loop $\delta L/L$ being up to $5 \cdot 10^{-5}$. The behavior of the loop is anomalous: the length changes so that it is in front of its equilibrium value. The hysteresis loop couples with that of conductivity. The sign and the value of the length hysteresis are consistent with the strain dependence of the charge-density waves (CDW) wave vector. With lowering temperature down to 100 K the CDW elastic modulus grows achieving a value comparable with the lattice Young modulus. Our results could be helpful in consideration of different systems with intrinsic superstructures.Comment: 4 pages, 3 figures. Phys. Rev. Lett., accepted for publicatio

The role of multimodal neuromonitoring during anesthesia for ablation of giant endocranial tumors

Catedra de anesteziologie și reanimatologie nr.2, Catedra de anesteziologie și reanimatologie nr.1 „Valeriu Ghereg”, Catedra de neurochirurgie, USMF „Nicolae Testemițanu”, Chișinău, Republica Moldova, Conferința stiințifică „Nicolae Anestiadi – nume etern al chirurgiei basarabene” consacrată centenarului de la nașterea profesorului Nicolae Anestiadi 26 august 2016Material şi metode. În studiu au fost incluse 2 loturi de pacienţi: I lot– 6 pacienţi cărora li s-a administrat anestezie combinată (i/v + pivot inhalator cu sevofluran); lotul II– 5 pacienţi cărora li s-a administrat anestezie totală intravenoasă (propofol+fentanil). Monitoring: TAs, TAd, TAm (invaziv), PVC, echilibru acidobazic, gazos (arteră şi venă periferică, bulbul jugular), electrolitic, acidul lactic, diurezei orară, PESS. Discuţii. În lotul pacienţilor cu anestezie inhalatorie s-a determinat o incidenţă înaltă a depresiei hemodinamice profunde (Tam - 74,3 mmHg, p= 0,02). Tot aici s-a determinat: utilizarea dozelor mai mici de analgetice şi miorelaxante (sol. atracurium bromid 0,35-0,4mg/kg) , trezire mai rapidă, incidenţă mai scăzută a greții şi tremorului postoperator. S-a reuşit efectuarea mai veridică a neuromonitorigului, datorită cantităţii mai mici de miorelaxante utilizate. La pacienţii cu anestezie intravenoasă s-a determinat o stabilitate hemodinamică (Tam - 82,7 mmHg, p ≤ 0,05), hemoragie intraoperatorie nesemnificativă. În lotul dat s-a reuşit efectuarea neuromonitorigului, cu doze obişnuite de miorelaxante (sol. atracurium bromid 0,5 mg/kg). Concluzii. Tehnicile descrise pot fi utilizate pentru neuromonitorizare multimodală în ablaţia de tumori endocraniene. Tehnica de anestezie inhalatorie, respectând farmacocinetica preparatelor, ar putea fi de preferat, din cauza evitării riscurilor de supra - sau sub dozare de medicamente anestezice, oferind o trezire mai rapidă, cu o evaluarea neurologică imediată, care este extrem de importantă.Materials and methods. The study included two groups of patients: I-st group - 6 patients receiving combined anesthesia (i / v + inhaled sevoflurane); II-nd group - 5 patients who received intravenous anesthesia (propofol + fentanyl).Monitoring: sBP, dBP, mBP (invasive), CVP, acid-base, gas (peripheral artery and vein, jugular bulb) and electrolytic balances, lactic acid, hourly diuresis, neurology evoked potentials. Discussion. In the group of patients with inhalation anesthesia was determined a higher incidence of hemodynamic depression (Tam - 74,3 mmHg, p= 0,02). Also it was determined: use of lower doses of analgetics and muscle relaxants (sol. atracurium bromid 0,35-0,4mg/kg), faster awakening, lower incidence of postoperative nausea and tremors. We managed a more accurate recording of evoked potentials due to the small amount of muscle relaxant used. In patients with intravenous anesthesia was determined a more stable BP (mBP - 82,7 mmHg, p ≤ 0,05), less intraoperative bleeding. In the group given was carrying neuromonitorigului managed with dose of muscle relaxant common (ground. atracurium aromide 0.5 mg / kg). Conclusions. The techniques described can be used for multimodal neuromonitoring in ablation of tumor endocranial. Inhalational anesthesia technique, respecting the pharmacokinetics preparations could be preferable because avoid the risks of over - or under dosage of anesthetic agents, providing an awakening faster with immediate neurological evaluation, which is extremely important

Progress in reducing ICRF-specific impurity release in ASDEX upgrade and JET

Use of new 3-strap ICRF antennas with all-tungsten (W) limiters in ASDEX Upgrade results in a reduction of the W sources at the antenna limiters and of the W content in the confined plasma by at least a factor of 2 compared to the W-limiter 2-strap antennas used in the past. The reduction is observed with a broad range of plasma shapes. In multiple locations of antenna frame, the limiter W source has a minimum when RF image currents are decreased by cancellation of the RF current contributions of the central and the outer straps. In JET with ITER-like wall, ITER-like antenna produces about 20% less of main chamber radiation and of W content compared to the old A2 antennas. However the effect of the A2 antennas on W content is scattered depending on which antennas are powered. Experiments in JET with trace nitrogen (N 2 ) injection show that a presence of active ICRF antenna close to the midplane injection valve has little effect on the core N content, both in dipole and in -90 °phasing. This indicates that the effect of ICRF on impurity transport across the scape-off-layer is small in JET compared to the dominant effect on impurity sources leading to increased impurity levels during ICRF operation.EURATOM 633053US Department of Energy DE-AC05-00OR2272