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Chiral Surface Plasmon Polaritons on Metallic Nanowires

Chiral surface plasmon polaritons (SPPs) can be generated by linearly polarized light incident at the end of a nanowire, exciting a coherent superposition of three specific nanowire waveguide modes. Images of chiral SPPs on individual nanowires obtained from quantum dot fluorescence excited by the SPP evanescent field reveal the chirality predicted in our theoretical model. The handedness and spat

Phase Measurement of a Fano Resonance Using Tunable Attosecond Pulses

We study photoionization of argon atoms close to the 3s(2)3p(6) -> 3s(1)3p(6)4p Fano resonance using an attosecond pulse train and a weak infrared probe field. An interferometric technique combined with tunable attosecond pulses allows us to determine the phase of the photoionization amplitude as a function of photon energy. We interpret the experimental results using an analytical two-photon mode

Photoprotection in a purple phototrophic bacterium mediated by oxygen-dependent alteration of carotenoid excited-state properties

Carotenoids are known to offer protection against the potentially damaging combination of light and oxygen encountered by purple phototrophic bacteria, but the efficiency of such protection depends on the type of carotenoid. Rhodobacter sphaeroides synthesizes spheroidene as the main carotenoid under anaerobic conditions whereas, in the presence of oxygen, the enzyme spheroidene monooxygenase cata

General Approach to the Evolution of Singlet Nanoparticles from a Rapidly Quenched Point Source

Among the numerous point vapor sources, microsecond-pulsed spark ablation at atmospheric pressure is a versatile and environmentally friendly method for producing ultrapure inorganic nanoparticles ranging from singlets having sizes smaller than 1 nm to larger agglomerated structures. Due to its fast quenching and extremely high supersaturation, coagulational growth already begins at the atomic sca

Direct Impact of Nonequilibrium Aggregates on the Structure and Morphology of Pdadmac/SDS Layers at the Air/Water Interface

We discuss different nonequilibrium mechanisms by which bulk aggregates directly modify, and can even control, the interfacial structure and morphology of an oppositely charged polyelectrolyte/surfactant (P/S) mixture. Samples are categorized at the air/water interface with respect to the dynamic changes in the bulk phase behavior, the bulk composition, and the sample history using complementary s

Evaluation of user hand and body impact on multiple antenna handset

From our experimental investigation of multiple-antenna performance and user impact of a realistic mobile terminal setup, we find that apart from the important loss of efficiency due to the user hand, the impact on the individual antennna elements and the directional impact of the user body shadowing have quite small influence on the diversity and capacity performance. It is found that the top and

Decline of C-peptide during the first year after diagnosis of Type 1 diabetes in children and adolescents

Aims/hypothesis: We studied the decline of C-peptide during the first year after diagnosis of Type 1 diabetes (T1D), and its relation to various factors. Methods: 3824/4017 newly diagnosed patients (95%) were classified as T1D in a national study. In a non-selected subgroup of 1669 T1D patients we determined non-fasting C-peptide both at diagnosis and after 1 year, and analyzed decline in relation

A porous silicon immunoassay platform for fluorometric determination of alpha-synuclein in human cerebrospinal fluid

Levels of total and/or oligomeric alpha-synuclein may be used as a biomarker tool to aid in the diagnosis and development of new disease-modifying therapies. We report here on a porous silicon antibody microarray for the fluorimetric determination of cerebrospinal fluid levels of total alpha-synuclein, a protein involved the pathology of Parkinson's disease. The surface of porous silicon has a 3-d

Fair Flow Rate Optimization by Effective Placement of Directional Antennas in Wireless Mesh Networks

Directional antennas have been used to solve interference and connectivity issues in wireless networks for some time. Many scenarios have been presented and often positive conclusions are drawn, i.e., showing the increase in capacity. However, to date the research has mainly focused on either antenna placement or transmission scheduling but not the two combined. Such consideration will become incr

Increasing returns to schooling by ability? A comparison between the USA and Sweden

This study uses US survey data and Swedish register data to estimate and compare the relationship between returns to schooling and ability. A significant and positive relationship is found for Sweden, but not for the USA. Based on the predictions of the optimal schooling model it is argues that measured differences in the relationship between returns to schooling and ability could depend upon on d

Case-control estimation of the impact of oncolytic adenovirus on the survival of patients with refractory solid tumors.

Oncolytic immunotherapy with cytokine armed replication competent viruses is an emerging approach in cancer treatment. In a recent randomized trial an increase in response rate was seen but the effect on overall survival is not known with any virus. To facilitate randomized trials, we performed a case-control study assessing the survival of 270 patients treated in an Advanced Therapy Access Progra

Soil microbial community structure and biomass as affected by Pinus pinea plantation in two Mediterranean areas

Stone pine (Pinus pinea L.) has been widely introduced for afforestation in Mediterranean areas. Despite its wide distribution and its presence since ancient time, it is mostly considered as non-native to the Italian peninsula. Plantation of non-native species may have a strong impact on the soil microbial community and, consequently, on nutrient cycling and soil functions. The effect of stone pin

Insertion of Heme b into the Structure of the Cys34-Carbamidomethylated Human Lipocalin a1-Microglobulin: Formation of a [(Heme)2(a1-Microglobulin)]3 Complex

a1-Microglobulin (a1m) is a 26 kDa plasma and tissue protein belonging to the lipocalin protein family. Previous investigations indicate that the protein interacts with heme and suggest that it has a function in heme metabolism. However, detailed characterizations of the a1mheme interactions are lacking. Here, we report for the first time the preparation and analysis of a stable a1mheme complex up

Experimental Validation Of Finite Element Model For Proximal Composite Femur Using Optical Measurements

Patient-specific finite element models have been used to predict femur strength and fracture risk in individuals. Validation of the adopted finite element modelling procedure against mechanical testing data is a crucial step when aiming for clinical applications. The majority of the works available in literature used data from strain gages to validate the model, thus having up to 15 experimental

Towards the multi-scale simulation of martensitic phase-transformations: An efficient post-processing approach applied to turning processes

This work presents an efficient finite element based scheme for the prediction of process properties and especially the material condition of workpiece surfaces after turning. This is achieved by using a database generated with the help of a micromechanically motivated material model - capable of simulating interactions of phase transitions and plasticity - for the efficient post-processing of a m

Measurement of Higgs boson production in the diphoton decay channel in pp collisions at center-of-mass energies of 7 and 8 TeV with the ATLAS detector

A measurement of the production processes of the recently discovered Higgs boson is performed in the two-photon final state using 4.5 fb(-1) of proton-proton collisions data at root s = 7 TeV and 20.3 fb(-1) at root s = 8 TeV collected by the ATLAS detector at the Large Hadron Collider. The number of observed Higgs boson decays to diphotons divided by the corresponding Standard Model prediction, c