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Probing Control of Fed-batch Cultures: Analysis and Tuning

Production of various proteins can today be made using genetically modified Escherichia coli bacteria. In cultivations of E. coli it is important to avoid accumulation of the by-product acetate. Formation of acetate occurs when the specific glucose uptake exceeds a critical value and can be avoided by a proper feeding strategy. A difficulty is that the critical glucose uptake often is poorly known

Functional aspects of secondary carotenoids in haematococcus lacustris (volvocales). III. Action as a "sunshade"

We investigated the protection from photoinhibition by different developmental stages of Haematococcus lacustris [Girod] Rostafinski using chlorophyll fluorescence measurements of single cells and suspensions. An overall correlation between higher cellular content of secondary carotenoids and the capacity to withstand excessive irradiation was observed in flagellated cells and aplanospores of H. l

Neural circuits and their structural and chemical reorganization in the light-brain-pituitary axis during parr-smolt transformation in salmon

Salmonid parr-smolt transformation (smoltification) is a transitional stage between freshwater and seawater life when the salmon imprint on their natal stream, change from a territorial feeding behavior to downstream migration, increase their hypoosmoregulatory competence, and change body shape and coloration. Photoperiod is recognized as the most potent initiator and regulator of the smoltificati

Thrombin generation assay: a useful routine check-up tool in the management of patients with haemophilia?

Severity assessment of patients with haemophilia A (HA) is traditionally based on FVIII activity (FVIII:C). Clinical phenotype of HA patients often differs between individuals with the same FVIII:C determined with clotting and chromogenic assays. The aim of this study was to assess the influence of the FVIII:C on thrombin generation (TG) assay parameters both in vitro and ex-vivo postinfusion plas

Quality issues in harvested rainwater in arid and semi-arid Loess Plateau of northern China

Loess soils cover vast areas in the arid and semi-arid regions of northern China. Due to the lack of reliable surface water and ground-water, rainwater harvesting has played a prominent role in farmers' domestic usage and agricultural irrigation. An economical arid valid type of water storage cistern with optimum design of components has been introduced to rural areas in the Loess Plateau. Differe

Host specificity in avian blood parasites: a study of Plasmodium and Haemoproteus mitochondrial DNA amplified from birds

A fragment of the mitochondrial cytochrome b gene of avian malaria (genera Haemoproteus and Plasmodium) was amplified from blood samples of 12 species of passerine birds from the genera Acrocephalus, Phylloscopus and Parus. By sequencing 478 nucleotides of the obtained fragments, we found 17 different mitocholdrial haplotypes of Haemoproteus or Plasmodium among the 12 bird species investigated. On

Sensorimotor performance and rotation correlate to lesion size in right but not left hemisphere brain infarcts in the spontaneously hypertensive rat

In order to correlate behavioural deficits to lesion size and to reveal possible functional asymmetries in the rat brain, locomotor activity, rotation and sensorimotor integration to touch were studied in spontaneously hypertensive rats (SHR) subjected to right or left middle cerebral artery occlusion. Control and infarcted rats showed no difference in locomotor activity. Infarcted rats tended to

Sodium-calcium balance in nonionic contrast media. Effects on the risk of ventricular fibrillation in the isolated rabbit heart

RATIONALE AND OBJECTIVES. During coronary arteriography the blood is replaced for a short period of time with a contrast medium (CM) solution. The CM may cause a risk of arrhythmias and ventricular fibrillation (VF). Previous investigations have shown that the addition of small amounts of sodium (10-30 mmol/L) to nonionic CM may decrease the risk of VF from these media. Calcium addition to nonioni

Electronic structure of nanometer-scale GaAs whiskers

We report a theoretical study of the electronic structure of GaAs nanowhiskers, grown in the [111] direction with hexagonal cross section, based on a tight binding approach. It is shown that the band structure of the GaAs nanowhiskers shifts from a direct band gap to an indirect band gap when the lateral size of the nanowhiskers becomes smaller than a certain value. The effective masses of the ele

The MAP kinases are differently utilized by CD28 and CD2 adhesion pathways in superantigen-activated Jurkat T cells

To mimic the two-signal requirements for T cell activation mediated by ligands, we exposed the superantigens SEA or SEE (signal 1) to T cells incubated with HLA-DR/LFA-3 or HLA-DR/137-1-CHO transfected cells (signal 2). LFA-3 costimulation was able to induce T cell proliferation as well as IFN-gamma and IL-4 production at similar levels as in cells induced by B7-1. Analysis of the CD28RE of the IL

Assessment of energy performance in the life-cycle of biogas production

Energy balances are analysed from a life-cycle perspective for biogas systems based on 8 different raw materials. The analysis is based on published data and relates to Swedish conditions. The results show that the energy input into biogas systems (i.e. large-scale biogas plants) overall corresponds to 20-40% (on average approximately 30%) of the energy content in the biogas produced. The net ener

Species delimitation and evolution of metal bioaccumulation in the lichenized Acarospora smaragdula (Ascomycota, Fungi) complex

The crustose lichenized fungi in the Acarosporaceae are splendid examples of organisms managing to survive in extremely harsh environments, such as highly mineralized rocks and low-pH habitats. Some representatives of the Acarospora smaragdula complex are known to accumulate substantial amounts of potentially toxic metals including iron and copper, resulting in populations with highly divergent co

Distance mapping of protein-binding sites using spin-labeled oligosaccharide ligands

The binding of a nitroxide spin-labeled analog of N-acetyllactosamine to galectin-3, a mammalian lectin of 26 kD size, is studied to map the binding sites of this small oligosaccharide on the protein surface. Perturbation of intensities of cross-peaks in the (15)N heteronuclear single quantum coherence (HSQC) spectrum of full-length galectin-3 owing to the bound spin label is used qualitatively to

Health-related quality of life and distress in cancer patients: results from a large randomised study

To compare the effectiveness of individual support, group rehabilitation and a combination of the two in improving health-related quality of life (HRQOL) and psychological well-being in cancer patients during 24 months after diagnosis, as compared with standard care (SC). Furthermore, to compare the study sample and a random sample of the Swedish population with regard to HRQOL. A total of 481 con

Enhanced proton beams from ultrathin targets driven by high contrast laser pulses

The generation of proton beams from ultrathin targets, down to 20 nm in thickness, driven with ultrahigh contrast laser pulses is explored. the conversion efficiency from laser energy into protons increases as the foil thickness is decreased, with good beam quality and high efficiencies of 1% being achieved, for protons with kinetic energy exceeding 0.9 MeV, for 100 nm thick aluminum foils at inte