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Absorption Efficiency and Physical Bounds on Antennas

Abstract—The all spectrum absorption efficiency appears in the physical bounds on antennas expressed in the polarizability dyadics. Here, it is shown that this generalized absorption efficiency is close to 1/2 for small idealized dipole antennas and for antennas with a dominant resonance in their absorption. Also, the usefulness of this parameter is analyzed for estimation of antenna performance.

Dynamic gradients of an intermediate filament-like cytoskeleton are recruited by a polarity landmark during apical growth.

Intermediate filament (IF)-like cytoskeleton emerges as a versatile tool for cellular organization in all kingdoms of life, underscoring the importance of mechanistically understanding its diverse manifestations. We showed previously that, in Streptomyces (a bacterium with a mycelial lifestyle similar to that of filamentous fungi, including extreme cell and growth polarity), the IF protein FilP co

Genotype-phenotype Correlations, and Retinal Function and Structure in von Hippel-Lindau Disease.

Abstract Purpose: To investigate genotype-phenotype correlation and to analyze functional and structural changes in the retina of patients with von Hippel-Lindau (VHL) disease. Methods: Thirteen patients from four families (A, B, C and D) with known VHL disease and known mutations in the VHL gene were examined. All patients underwent clinical examination and optical coherence tomography (OCT). Ful

Rheological characterization of dilute acid pretreated softwood.

Large-scale bioethanol production from lignocellulosic biomass will require high solids loading in the enzymatic hydrolysis step. However, slurries of pretreated lignocelluloses are complex fluids due to the fibrous nature, especially at high concentrations of water insoluble solids (WIS). A prerequisite for dealing with transport issues and for developing efficient full-scale processes is a funda

Integration of polarization and chromatic cues in the insect sky compass.

Animals relying on a celestial compass for spatial orientation may use the position of the sun, the chromatic or intensity gradient of the sky, the polarization pattern of the sky, or a combination of these cues as compass signals. Behavioral experiments in bees and ants, indeed, showed that direct sunlight and sky polarization play a role in sky compass orientation, but the relative importance of

The effects of fly-bys on planetary systems

Most of the observed extrasolar planets are found on tight and often eccentric orbits. The high eccentricities are not easily explained by planet-formation models, which predict that planets should be on rather circular orbits. Here we explore whether fly-bys involving planetary systems with properties similar to those of the gas giants in the Solar system can produce planets with properties simil

New evidence of Holocene atmospheric circulation dynamics based on lake sediments from southern Sweden: a link to the Siberian High

Oxygen (delta O-18) and carbon (delta C-13) isotope records of calcitic carbonate components (Chara sp. algal encrustations and Bithynia tentaculata gastropod opercula) from a lake-sediment succession on the Baltic Sea island of Gotland, south-eastern Sweden, have been obtained to investigate regional climate dynamics during the Holocene. The hydrological sensitivity of the small lake, particularl

Using geographical information systems to identify populations in need of improved accessibility to antivenom treatment for snakebite envenoming in costa rica.

INTRODUCTION: Snakebite accidents are an important health problem in rural areas of tropical countries worldwide, including Costa Rica, where most bites are caused by the pit-viper Bothrops asper. The treatment of these potentially fatal accidents is based on the timely administration of specific antivenom. In many regions of the world, insufficient health care systems and lack of antivenom in rem

Anthropometric measures in relation to risk of heart failure hospitalization: a Swedish population-based cohort study.

BACKGROUND: It is unclear which anthropometric measure is most useful for assessment of the cardiovascular risk. We investigated the association between different anthropometric measures and risk of heart failure (HF) hospitalization. METHODS: BMI, waist-hip ratio (WHR), waist circumference (WC), body fat percentage (BF%), weight and height were measured among 26 653 subjects (aged 45-73 years) wi

Chitosan tubes of varying degrees of acetylation for bridging peripheral nerve defects

Biosynthetic nerve grafts are desired as alternative to autologous nerve grafts in peripheral nerve reconstruction. Artificial nerve conduits still have their limitations and are not widely accepted in the clinical setting. Here we report an analysis of fine-tuned chitosan tubes used to reconstruct 10 mm nerve defects in the adult rat. The chitosan tubes displayed low, medium and high degrees of a

Human endogenous peptide p33 inhibits detrimental effects of LL-37 on osteoblast viability.

High levels of the antimicrobial peptide, LL-37, are detected in gingival crevicular fluid from patients with chronic periodontitis. LL-37 not only shows antimicrobial activity but also affects host-cell viability. The objective of the present study was to identify endogenous mechanisms that antagonize the detrimental effects of LL-37 on osteoblast viability, focusing on the human peptide p33 expr

Atomic Wehrl Entropy of a Single Qubit System

We propose the use of atomic Wehrl entropy associated to the reduced atomic density operator as an entanglement indicator of bipartite systems. This is applied to a two-level system (one single harmonically trapped ion) by taking into account the linear center-of-mass-motional degree of freedom. Detailed analytical and explicit expressions are given, taking into account different configurations. T

Cold-Nuclear-Matter Effects on Heavy-Quark Production at Forward and Backward Rapidity in d + Au Collisions at root s(NN) = GeV

The PHENIX experiment has measured open heavy-flavor production via semileptonic decay over the transverse momentum range 1 < p(T) < 6 GeV/c at forward and backward rapidity (1.4 < vertical bar y vertical bar < 2.0) in d + Au and p + p collisions at root s(NN) = 200 GeV. In central d + Au collisions, relative to the yield in p + p collisions scaled by the number of binary nucleon-nucleon collision

Simultaneous Visualization of Water and Hydrogen Peroxide Vapor Using Two-Photon Laser-Induced Fluorescence and Photofragmentation Laser-Induced Fluorescence

A concept based on a combination of photofragmentation laser-induced fluorescence (PF-LIF) and two-photon laser-induced fluorescence (LIF) is for the first time demonstrated for simultaneous detection of hydrogen peroxide (H2O2) and water (H2O) vapor. Water detection is based on two-photon excitation by an injection-locked krypton fluoride (KrF) excimer laser (248.28 nm), which induces broadband f

Anisotropic electric fluctuations in polar liquids under spherical confinement

The anisotropic local electric fluctuations within a nanoscopic sphere of a polar fluid surrounded by vacuum are analysed using dielectric theory and molecular simulation. The electric fluctuations are characterized through the mean-square multipole moments (Q(l)(2)), which are related to the dielectric constant of the fluid. The results show that the fluctuations are suppressed close to the fluid