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Tin Oxides : Insights into Chemical States from a Nanoparticle Study

Tin oxides are semiconductor materials currently attracting close attention in electronics, photovoltaics, gas sensing, and catalysis. Depending on the tin oxidation state - Sn(IV), Sn(II), or intermediate - the corresponding oxide has either n- or p-type natural conductivity, ascribed to oxygen or metal deficiency in the lattice. Such crystalline imperfections severely complicate the task of esta

Nonadiabaticity of cavity-free neutral nitrogen lasing

We report on a theoretical study of cavity-free lasing of neutral nitrogen molecules in femtosecond laser filaments with a nonadiabatic Maxwell-Bloch model, compared with recent pump-seed experiments. The nonadiabaticity of the lasing process is revealed and it is found that electron-neutral collisions dominate the dipole dephasing rate. Moreover, we show that the asymmetry between forward and bac

On the thermal degradation of tunnel diodes in multijunction solar cells

Tunnel junctions are essential components of multijunction solar cells. These highly doped p/n junctions provide the electrical interconnect between the subcells that constitute a multijunction solar cell device. The conductivity and the peak tunneling current of tunnel diodes are known to be severely affected by thermal load. This is a general phenomenon observed in tunnel junctions despite the m

Regularization and Interpolation of Positive Matrices

We construct certain matricial analogues of mass transport for positive definite matrices of equal trace. The framework aims to devise ways of interpolating positive definite matrices that tradeoff between "aligning up their eigenstructure" and "scaling the corresponding eigenvalues". Motivation for the work is provided by power spectral analysis of multivariate time series where linear interpolat

Spatially resolved spectroscopy across stellar surfaces : II. High-resolution spectra across HD 209458 (G0 V)

Context. High-resolution spectroscopy across spatially resolved stellar surfaces aims at obtaining spectral-line profiles that are free from rotational broadening; the gradual changes of these profiles from disk center toward the stellar limb reveal properties of atmospheric fine structure, which are possible to model with 3D hydrodynamics. Aims. Previous such studies have only been carried out fo

Characterization of an AC glow-type gliding arc discharge in atmospheric air with a current-voltage lumped model

Quantitative characterization of a high-power glow-mode gliding arc (GM-GA) discharge operated in open air is performed using a current-voltage lumped model that is built from the perspective of energy balance and electron conservation. The GM-GA discharge is powered by a 35 kHz alternating current power supply. Instantaneous images of the discharge volume are recorded using a high-speed camera at

Further support for the motivational explanation of self-other similarity judgment asymmetry

Self-other similarity judgment asymmetry refers to the tendency of people to judge others to be more similar to themselves than they judge themselves to be similar to others. This effect can be explained with both a cognitive model (Tversky, 1977) and a motivational explanation (Codol, 1987). Recent research has provided initial evidence for the core assumption of the motivational explanation and

Improved scatter correction with factor analysis for planar and SPECT imaging

Quantitative nuclear medicine imaging is an increasingly important frontier. In order to achieve quantitative imaging, various interactions of photons with matter have to be modeled and compensated. Although correction for photon attenuation has been addressed by including x-ray CT scans (accurate), correction for Compton scatter remains an open issue. The inclusion of scattered photons within the

Chemical evolution of the Galactic bulge as traced by microlensed dwarf and subgiant stars : VI. Age and abundance structure of the stellar populations in the central sub-kpc of the Milky Way

We present a detailed elemental abundance study of 90 F and G dwarf, turn-off, and subgiant stars in the Galactic bulge. Based on high-resolution spectra acquired during gravitational microlensing events, stellar ages and abundances for 11 elements (Na, Mg, Al, Si, Ca, Ti, Cr, Fe, Zn, Y and Ba) have been determined. Four main findings are presented: (1) a wide metallicity distribution with distinc

In the name of managerialism : Reforming organizations in the Swedish public sector

This paper focuses on the translation of managerialism in the Swedish public sector. A field study of the attempts by two large municipalities to launch a grand reform in the name of managerialism, that is, a purchasersupplier reform, shows the by now familiar difficulties of trying to change public organizations. Thus the actual consequences of actions taken in the name of managerialism are perha

Can suitable candidates for levodopa/carbidopa intestinal gel therapy be identified using current evidence?

Advanced Parkinson's disease (APD) is characterized by increased functional disability, caused by motor complications, the presence of axial symptoms, and emergent disease- and drug-related non-motor symptoms. One of the advanced therapies available is intrajejunal infusion of levodopa/carbidopa intestinal gel (LCIG); however, patient selection for this treatment is sometimes difficult, particular

Analysis of hypo- and hyperphosphatemia in an intensive care unit cohort

BACKGROUND: Blood phosphate levels are vulnerable to fluctuations and changes in phosphate levels are often neglected. The aim of this study was to evaluate whether deviations in phosphate levels correlate to higher 180-day overall mortality or morbidity. METHODS: Four thousand six hundred fifty-six patients with 19,467 phosphate values treated at the adult intensive care unit at Skåne University

The economic burden of human papillomavirus-related precancers and cancers in Sweden

High-risk (HR) human papillomavirus (HPV) infection is an established cause of malignant disease. We used a societal perspective to estimate the cost of HR HPV-related cervical, vulvar, vaginal, anal, and penile precancer and cancer, and oropharyngeal cancer in Sweden in 2006, 1 year before HPV vaccination became available in the country. Materials and methods This prevalence-based cost-of-illness