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Assignment of the low-temperature fluorescence in oxygen-evolving Photosystem II

Low-temperature absorption and fluorescence spectra of fully active cores and membrane-bound PS II preparations are compared. Detailed temperature dependence of fluorescence spectra between 5 and 70 K are presented as well as 1.7-K fluorescence line-narrowed (FLN) spectra of cores, confirming that PS II emission is composite. Spectra are compared to those reported for LHCII, CP43, CP47 and D1/D2/c

Crystal structure of Thermatoga mritima ribosome recycling factor: A tRNA mimic

Ribosome recycling factor (RRF), together with elongation factor G (EF-G), catalyzes recycling of ribosomes after one round of protein synthesis. The crystal structure of RRF was determined at 2.55 angstrom resolution. The protein has an unusual fold where domain I is a long three-helix bundle and domain II is a three-layer β/α/β sandwich. The molecule superimposes almost perfectly with a transfer

Driving to Learn. The process of growing consciousness of tool use - a grounded theory of de-plateauing.

Popular Abstract in Swedish Denna avhandling presenterar en teori om hur utforskande och hantering av verktyg kan få människor att överskrida förutfattade begränsningar. Personer med grava kognitiva funktionshinder har mycket svåra begränsningar i sina förutsättningar att delta i aktiviteter som kan skapa mål och mening och bidra till förändringar i deras liv. De har svårartade inskränkningar närThe Driving to Learn project explored possible achievements of training people with cognitive disabilities in a joystick-operated powered wheelchair utilizing the grounded theory approach. Theoretical sampling led the concomitant collection and analysis of data. During a period of 12 years, 45 participants with profound cognitive disabilities, aged 12 months to 52 years, were engaged in the projec

Constraining the density and complex refractive index of elemental and organic carbon in biomass burning aerosol using optical and chemical measurements

The role of biomass burning aerosols in the climate system is still poorly quantified, in part due to uncertainties regarding the optical properties of elemental and organic carbon (EC and OC, respectively), the main constituents of pyrogenic aerosols. In this study, we utilize comprehensive physical and chemical field measurements of biomass burning aerosols in Brazil to constrain the densities a

Exposure-Based Cash-Flow-at-Risk: An Alternative to VaR for Industrial Companies

Abstract in UndeterminedCash-Flow-at-Risk (CFaR) is the cash flow equivalent of Value-at-Risk (VaR), a measure widely used as the basis for risk management in financial institutions. Whereas VaR-based systems specify the maximum amount of total value a firm is expected to lose under most foreseeable conditions (for example, with a 99% confidence level), CFaR-based systems determine the maximum sho

Sensitivity analysis for antenna near-field imaging

Although imaging and inverse scattering problems have been thoroughly studied during the last century, there is only a partial understanding of these complex problems. Most of the efforts have been placed on the development of efficient inversion algorithms and mathematical uniqueness results. In comparison, there are very few results and a limited knowledge about the information content in the in

Increasing Product Quality by Verification and Validation Improvements in an Industrial Setting

Large and complex software systems are developed as a tremendous engineering effort. The aim of the development is to satisfy the customer by delivering the right product, with the right quality, and on time. Errors made by engineers will always occur when a system is developed, but their number can be decreased by process improvement and their effect can be reduced by removing them as early as po

Contractile properties of lymphatics from the human lower leg

Lower leg lymphatics, taken from seven volunteers, were investigated in vitro. Isometric contractions were induced by noradrenaline, 5-hydroxytryptamine (5-HT), prostaglandin F2 alpha (PGF2 alpha), and the thromboxane A2 (TXA2)-mimetic U-44069. Noradrenaline induced phasic contractions in 6 of 7 segments. The amplitude of the contractions were up to 100% of a previous K+ (124mM)-induced contractio

Long-acting beta(2)-agonists: how are they used in an optimal way?

Inhaled long-acting beta(2)-agonists are frequently used for the treatment of asthma. When introduced to the market, the drug was accompanied by a debate among physicians and scientists raising warnings against the use of beta(2)-agonists, leading to a risk of tachyphylaxis and worsening of asthma control. During recent years, much of these warnings have been counter proved and there has been a te

Some Studies of the Transport Coefficients of Pulp and Paper

Popular Abstract in Swedish Torkning av ett poröst material sker i två perioder: en period med konstant torkhastighet och en period med fallande torkhastighet. Under perioden med konstant torkhastighet, bestäms torkhastigheten av de yttre förhållandena beträffande värme- och masstransport, och torkhastigheten påverkas inte av det torkande materialets egenskaper. Under perioden med fallande torkhasThe drying of a porous material occurs in two different periods: the constant rate period and the falling rate period. During the constant rate period, the drying rate is determined by the external conditions regarding heat and mass transfer, and the drying rate is not influenced by the properties of the drying material. During the falling rate period, the material properties, such as the transpor

Search for single top quark production in ep collisions at HERA

A search for single top quark production is performed in e(+/-) pcollisions at HERA. The search exploits data corresponding to an integrated luminosity of 118.3 pb(-1). A model for the anomalous production of top quarks in a flavour changing neutral current process involving a tugamma coupling is investigated. Decays of top quarks into a b quark and a W boson are considered in the leptonic and the

Euploidy in somatic cells from R6/2 transgenic Huntington's disease mice

Background: Huntington's disease (HD) is a hereditary neurodegenerative disorder caused by a CAG repeat expansion in the HD gene. The huntingtin protein expressed from HD has an unknown function but is suggested to interact with proteins involved in the cell division machinery. The R6/2 transgenic mouse is the most widely used model to study HD. In R6/2 fibroblast cultures, a reduced mitotic index

Acquisition, extinction, and reacquisition of a cerebellar cortical memory trace.

Associative learning in the cerebellum underlies motor memories and probably also cognitive associations. Pavlovian eyeblink conditioning, a widely used experimental model of such learning, depends on the cerebellum, but the memory locus within the cerebellum as well as the underlying mechanisms have remained controversial. To date, crucial information on how cerebellar Purkinje cells change their

Penile intraepithelial neoplasia: Results of photodynarnic therapy

Failure of response to treatment or recurrent disease is often noted in patients with penile intraepithelial neoplasia. Photodynamic therapy has recently been added to the list of treatment modalities used for this diagnosis. Our primary objective was to study the results of photodynamic therapy in the treatment of penile intraepithelial neoplasia in men over the age of 40 years. Ten patients aged