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On a generalized matrix approximation problem in the spectral norm

Abstract in UndeterminedIn this paper theoretical results regarding a generalized minimum rank matrix approximation problem in the spectral norm are presented. An alternative solution expression for the generalized matrix approximation problem is obtained. This alternative expression provides a simple characterization of the achievableminimum rank, which is shown to be the same as the optimal obje

Parameter estimation approach to banding artifact reduction in balanced steady-state free precession

Purpose: The balanced steady-state free precession (bSSFP) pulse sequence has shown to be of great interest due to its high signal-to-noise ratio efficiency. However, bSSFP images often suffer from banding artifacts due to off-resonance effects, which we aim to minimize in this paper. Methods: We present a general and fast two-step algorithm for 1) estimating the unknowns in the bSSFP signal model

High precision astrometry mission for the detection and characterization of nearby habitable planetary systems with the Nearby Earth Astrometric Telescope (NEAT)

A complete census of planetary systems around a volume-limited sample of solar-type stars (FGK dwarfs) in the Solar neighborhood (d a parts per thousand currency signaEuro parts per thousand 15 pc) with uniform sensitivity down to Earth-mass planets within their Habitable Zones out to several AUs would be a major milestone in extrasolar planets astrophysics. This fundamental goal can be achieved w

Active Vitamin D (1,25-Dihydroxyvitamin D) and Bone Health in Middle-Aged and Elderly Men: The European Male Aging Study (EMAS).

Context:There is little information on the potential impact of serum 1,25-dihydroxyvitamin D [1,25(OH)(2)D] on bone health including turnover.Objective:The objective of the study was to determine the influence of 1,25(OH)(2)D and 25-hydroxyvitamin D [25(OH)D] on bone health in middle-aged and older European men.Design, Setting, and Participants:Men aged 40-79 years were recruited from population r

Monitoring fibrinolysis in whole blood by viscoelastic instruments: A comparison of ROTEM and ReoRox.

Objective. Increased fibrinolysis with the risk of bleeding is a consequence of thrombolytic therapy and can also be seen in clinical situations such as acute trauma. Thrombelastography and thrombelastometry are viscoelastic coagulation instruments that can detect higher degrees of fibrinolysis; hyperfibrinolysis. A newer viscoelastic instrument is the ReoRox, which uses free oscillation rheometry

Parallel Chains of Command in European Union Operation Headquarters: An Experimental Study of the Drivers behind National Perspectives

The European Union (EU) military Operation Headquarters (OHQ) construct has been described as a slow starter due to familiarization issues and an arena for parallel chains of command. Similarly, a recent study of a live OHQ showed national perspectives to be common, particularly with staff members from nations prominent in the operation. However, the nature of these flaws remains unclear while sch

Per-Vertex Defocus Blur for Stochastic Rasterization

We present user-controllable and plausible defocus blur for a stochastic rasterizer. We modify circle of confusion coefficients per vertex to express more general defocus blur, and show how the method can be applied to limit the foreground blur, extend the in-focus range, simulate tilt-shift photography, and specify per-object defocus blur. Furthermore, with two simplifying assumptions, we show th

Occupational Balance in People with Schizophrenia

The aim of this study was to illuminate the concept of occupational balance and to study its relation to occupational engagement as assessed by the POES, health related factors, and quality of life among 72 persons with schizophrenia. Three constructs: being under-occupied, being over-occupied, and having occupational balance, were developed to help assess occupational balance. The inter-reliabili

Porosity and Surface Properites of SBA-15 with Grafted PNIPAAM: A Water Sorption Calorimetry Study

Mesoporous silica SBA-15 was modified in a three-step process to obtain a material with poly-N-isopropylacrylamide (PNIPAAM) grafted onto the inner pore surface. Water sorption calorimetry was implemented to characterize the materials obtained after each step regarding the porosity and surface properties. The modification process was carried out by (i) increasing the number of surface silanol grou

Coronal lines and the importance of deep-core-valence correlation in Ag-like ions

We report on large-scale and critically evaluated ab initio multiconfiguration Dirac-Hartree-Fock calculations of the wavelength and transition rate of the "coronal," M1 transition 4f F-2(5/2)o-F-2(7/2)o in Ag-like ions. The transition between these two fine-structure levels, which makes up the ground term for Z >= 62 in the isoelectronic sequence, has recently been observed in Yb23+ and W27+, whe

Stretching capabilities: children with disabilities playing TV and computer games

Intervention studies show that if children with disabilities play motion-controlled TV and computer games for training purposes their motivation increases and their training becomes more intensive, but why this happens has not been explained. This article addresses this question with the help of ethnographic material from a public project in Sweden. By applying interactional constructionism to det

Cu particle seeded InP InAs axial nanowire heterostructures

We demonstrate the epitaxial growth of alternating InP-InAs nanowire heterostructures using Cu seed particles in MOVPE. We observe extraordinary early stages in the formation of InAs segments, e.g. three-dimensional nucleation instead of step-flow growth. Furthermore, InAs segments of thin nanowires exhibit extended 4H crystal structure.

Particle-assisted GaxIn1-xP nanowire growth for designed bandgap structures

Non-tapered vertically straight GaxIn1-xP nanowires were grown in a compositional range from Ga0.2In0.8P to pure GaP in particle-assisted mode by controlling the trimethylindium, trimethylgallium and hydrogen chloride flows in metal-organic vapor phase epitaxy. X-ray energy dispersive spectroscopy in transmission electron microscopy revealed homogeneous radial material composition in single nanowi

Snapshots of the Fluctuating Hydrogen Bond Network in Liquid Water on the Sub-Femtosecond Timescale with Vibrational Resonant Inelastic x-ray Scattering.

Liquid water molecules interact strongly with each other, forming a fluctuating hydrogen bond network and thereby giving rise to the anomalous phase diagram of liquid water. Consequently, symmetric and asymmetric water molecules have been found in the picosecond time average with IR and optical Raman spectroscopy. With subnatural linewidth resonant inelastic x-ray scattering (RIXS) at vibrational

Predicting ejaculate quality and libido in male ostriches: Effect of season and age.

The success of artificial breeding program depends largely on the reproductive performance of males. Male performance can vary with season and age impacting on quality and quantity of semen collected for artificial insemination purposes and therefore fertility of inseminated females. We examined variation in semen output and male libido of seven male ostriches (aged 2-5 years) over a period of 24

Interannual Coupling between Summertime Surface Temperature and Precipitation over Land: Processes and Implications for Climate Change

Widespread negative correlations between summertime-mean temperatures and precipitation over land regions are a well-known feature of terrestrial climate. This behavior has generally been interpreted in the context of soil moisture atmosphere coupling, with soil moisture deficits associated with reduced rainfall leading to enhanced surface sensible heating and higher surface temperature. The prese

Nonlinear response of quantum cascade structures

The gain spectrum of a terahertz quantum cascade laser is analyzed by a nonequilibrium Green's functions approach. Higher harmonics of the response function were retrievable, providing a way to approach nonlinear phenomena in quantum cascade lasers theoretically. Gain is simulated under operation conditions and results are presented both for linear response and strong laser fields. An iterative wa