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Porphyrin and Tetrabenzoporphyrin Dendrimers: Tunable Membrane-Impermeable Fluorescent pH Nanosensors

The pH dependencies of the UV-vis and fluorescent spectra of new water-soluble dendritic porphyrins and tetrabenzoporphyrins were studied. Because of extended -conjugation and nonplanar distortion, the absorption and the emission bands of tetraaryltetrabenzoporphyrins (Ar4TBP) are red-shifted and do not overlap with those of regular tetraarylporphyrins (Ar4P). When encapsulated inside dendrimers w

Generation of spin current and polarization under dynamic gate control of spin-orbit interaction in low-dimensional semiconductor systems

Based on the Keldysh formalism, the Boltzmann kinetic equation and the drift-diffusion equation have been derived for studying spin-polarization flow and spin accumulation under effect of the time-dependent Rashba spin-orbit interaction in a semiconductor quantum well. The time-dependent Rashba interaction is provided by time-dependent electric gates of appropriate shapes. Several examples of spin

Supersymmetric extensions of Calogero-Moser-Sutherland-like models: construction and some solutions

We introduce a new class of models for interacting particles. Our construction is based on Jacobians for the radial coordinates on certain superspaces. The resulting models contain two parameters determining the strengths of the interactions. This extends and generalizes the models of the Calogero-Moser-Sutherland type for interacting particles in ordinary spaces. The latter ones are included in o

On-line estimation of sugar concentration for control of fed-batch fermentation of lignocellulosic hydrolyzates by Saccharomyces cerevisiae

A feed control strategy, based on estimated sugar concentrations, was developed with the purpose of avoiding severe inhibition of the yeast Saccharomyces cerevisiae during fermentation of spruce hydrolyzate. The sum of the fermentable hexose sugars, glucose and mannose, was estimated from on-line measurements of carbon dioxide evolution rate and biomass concentration by use of a simple stoichiomet

Anatomy and biomechanics of the back muscles in the lumbar spine with reference to biomechanical modeling

Study Design. This article describes the development of a musculoskeletal model of the human lumbar spine with focus on back muscles. It includes data from literature in a structured form. Objective. To review the anatomy and biomechanics of the back muscles related to the lumbar spine with relevance for biomechanical modeling. Summary of Background Data. To reduce complexity, muscle units have be

Människor i utmark

Popular Abstract in Swedish Målsättningen med föreliggande studie är att belysa det komplexa och varierade bruket av skogliga utmarker under järnålder, medeltid och tidig modern tid. Fysiska lämningar från landskapet Värmland i västra Sverige undersöks, med särskilt fokus på lokalsamhällena Dalby och Gunnarskog. De fysiska lämningarna i fokus för denna studie är främst fångstgropar för älg, lågtekThe aim of this study is to illuminate the complex and varied uses of the forested outlands, from the Iron Age, through the Middle Ages, to Early Modern times. Material evidence from the landscape of Värmland, in Western Sweden, will be examined, focusing on the local societies of Dalby and Gunnarskog. Evidence for the reconstruction of outland activities comes from a range of sites, including pit

Evaluation of malignancy in ring enhancing brain lesions on CT by thallium-201 SPECT

OBJECTIVE: To investigate patients with cystic enhancing lesions on CT and to determine whether thallium-201 (201Tl) SPECT adds to further preoperative information in differential diagnosis between gliomas and abscesses. METHODS: Twenty one patients with cystic ring enhancing CT findings were studied and uptake indices were compared with CT enhancement volumes, histopathology, and survival times.

Prediction of death in patients with primary intracerebral hemorrhage: a prospective study of a defined population.

OBJECT: Predictors of early (30-day) and long-term (1-year) mortality rates after primary intracerebral hemorrhage (ICH) were studied in a large population in southern Sweden. METHODS: All cases of primary ICH, verified using computerized tomography (CT) scanning or autopsy study, were prospectively registered at the 12 hospitals covering a defined population of 1.14 million during the calendar ye

Experimental studies of attosecond pulse trains

We present experimental measurements of attosecond pulse trains. The characterization of the pulses uses a spectral interferometry technique that is implemented with a Mach-Zehnder interferometer. This allows us to manipulate independently the pump and probe pulses for a wide range of applications. By letting the attosecond pulses pass through metallic films, we can in particular compensate for th

Characterisation of anaerobic mixed cultures by partition in an aqueous two-phase system

A method to characterise a dynamic microbial consortium is described. By exploiting differences in surface properties between different cells and between cells of different physiological status, it was possible to develop a partition pattern for a mixed culture under different conditions. The separation method used was partition in aqueous two-phase systems and when using a counter current extract