Searching for better materials for plasmonic and metamaterial applications is an inverse design problem where theoretical studies are necessary. Using basic models of impurity doping in semiconductors, transparent conducting oxides (TCOs) are identified as low-loss plasmonic materials in the near-infrared wavelength range. A more sophisticated theoretical study would help not only to improve the properties of TCOs but also to design further lower-loss materials. In this study, optical functions of one such TCO, gallium-doped zinc oxide (GZO), are studied both experimentally and by first-principles density-functional calculations. Pulsed-laser-deposited GZO films are studied by the x-ray diffraction and generalized spectroscopic ellipsometry. Theoretical studies are performed by the total-energy-minimization method for the equilibrium atomic structure of GZO and random phase approximation with the quasiparticle gap correction. Plasma excitation effects are also included for optical functions. This study identifies mechanisms other than doping, such as alloying effects, that significantly influence the optical properties of GZO films. It also indicates that ultraheavy Ga doping of ZnO results in a new alloy material, rather than just degenerately doped ZnO. This work is the first step to achieve a fundamental understanding of the connection between material, structural, and optical properties of highly doped TCOs to tailor those materials for various plasmonic applications.

We have shown that alloying a noble metal (gold) with another metal (cadmium), which can contribute two electrons per atom to a free electron gas, can significantly improve the metal's optical properties in certain wavelength ranges and make them worse in the other parts of the spectrum. In particular, in the gold-cadmium alloy we have demonstrated a significant expansion of the spectral range of metallic reflectance to shorter wavelengths. The experimental results and the predictions of the first principles theory demonstrate an opportunity for the improvement and optimization of low-loss metals for nanoplasmonic and metamaterials applications.

Effective treatment of chronic lower limb ischemia is one of the most challenging issues confronting vascular surgeons. There are a number of choices available to the vascular surgeon. Open or endovascular revascularization is the treatment of choice when applicable. Current pharmacological therapies play an auxiliary role and cannot prevent disease progression. Therefore, new methods of treatment are needed. We conducted a phase 2b/3 multicenter randomized controlled clinical trial of the intramuscular transfer of a plasmid DNA encoding vascular endothelial growth factor (VEGF) 165 with cytomegalovirus promotor (CMV) in patients with atherosclerotic lower limb ischemia. A total of 100 patients were enrolled in the study, that is, 75 patients were randomized into the test group and received 2 intramuscular injections of 1.2 mg of pCMV-vegf165, 14 days apart together with standard pharmacological treatment. In all, 25 patients were randomized into the control group and received standard treatment only. The following end points were evaluated within the first 6 months of the study and during a 1.5-year additional follow-up period: pain-free walking distance (PWD), ankle-brachial index (ABI), and blood flow velocity (BFV). The pCMV-vegf165 therapy appeared to be significantly more effective than standard treatment. The PWD increased in the test group by 110.4%, 167.2%, and 190.8% at 6 months, 1 year, and 2 years after treatment, respectively. The pCMV-vegf165 intramuscular transfer caused a statistically significant increase in ABI and BFV. There were no positive results in the control group. Thus, pCMV-vegf165 intramuscular gene transfer is an effective method of treatment of moderate to severe claudication due to chronic lower limb ischemia.

Optical absorption spectra of poly(thiophene vinylene) (PTV) conjugated polymers have been studied at room temperature in the spectral range of 450 to 800 nm. A dominant peak located at 577 nm and a prominent shoulder at 619 nm are observed. Another shoulder located at 685 nm is observed at high concentration and after additional treatment (heat, sonification) only. Equilibrium atomic geometries and optical absorption of PTV conjugated polymers have also been studied by first principles density functional theory (DFT). For PTV in solvent, the theoretical calculations predict two equilibrium geometries with different interchain distances. By comparative analysis of the experimental and theoretical data, it is demonstrated that the new measured long-wavelength optical absorption shoulder is consistent with new optical absorption peak predicted for most energetically favorable PTV phase in the solvent. This shoulder is interpreted as a direct indication of increased interchain interaction in the solvent which has caused additional electronic energy structure transformations.

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The Brugada syndrome (BrS) is an inherited arrhythmia characterized by ST‐segment elevation in V1–V3 leads and negative T wave on standard ECG. BrS patients are at risk of sudden cardiac death (SCD) due to ventricular tachyarrhythmia. At least 17 genes have been proposed to be linked to BrS, although recent findings suggested a polygenic background. Mutations in SCN5A, the gene coding for the cardiac sodium channel Nav1.5, have been found in 15–30% of index cases. Here, we present the results of clinical, genetic, and expression studies of a large Iranian family with BrS carrying a novel genetic variant (p.P1506S) in SCN5A. By performing whole‐cell patch‐clamp experiments using HEK293 cells expressing wild‐type (WT) or p.P1506S Nav1.5 channels, hyperpolarizing shift of the availability curve, depolarizing shift of the activation curve, and hastening of the fast inactivation process were observed. These mutant‐induced alterations lead to a loss of function of Nav1.5 and thus suggest that the p.P1506S variant is pathogenic. In addition, cascade familial screening found a family member with BrS who did not carry the p.P1506S mutation. Additional next generation sequencing analyses revealed the p.R25W mutation in KCNH2 gene in SCN5A‐negative BrS patients. These findings illustrate the complex genetic background of BrS found in this family and the possible pathogenic role of a new SCN5A genetic variant.

The polar surfaces of ferroelectric LiNbO3 have been investigated by an ab initio thermodynamical approach. Basing on density functional theory total energy calculations, we discuss the relative stability of a series of candidate surface structures with varying stoichiometry and surface reconstruction in dependence on the chemical environment. We determine the equilibrium geometry for the positively and negatively polarised surfaces and then discuss the influence of different stabilising mechanisms on the preferred terminations. Positive and negative surfaces are found to have different structure, stoichiometry and ionisation energy. The positive surface is found to contain more oxygen than the negative surface at similar conditions. Different stabilisation mechanisms like stoichiometry modification and reconstruction contribute to stabilise the polar surfaces (© 2010 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)

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