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High temperature enzymatic prehydrolysis prior to simultaneous saccharification and fermentation of steam pretreated corn stover for ethanol production

As a consequence of heightened concern for the greenhouse effect, depleting oil reserves and skyrocketing oil prices, renewable fuels, Such as bioethanol, are becoming increasingly important. Cellulosic biomass like wood, agricultural residue and herbaceous material is a huge, cheap natural resource that can be used for ethanol production. Decreasing production costs through technological developm

Influence of fatigue load range on the growth of a microstructurally short edge crack simulated by a discrete dislocation formulation

Quasistatic propagation of a short edge crack, located within one grain of a bcc material has been studied using a discrete dislocation technique. The geometry is modelled by distributed dislocation dipole elements and the plasticity by discrete dislocations. The crack is assumed to grow through a single shear mechanism due to nucleation and annihilation of dislocations along preferred slip planes

The Stenshuvud and Taghusa granitoids: new representatives of Mesoproterozoic magmatism in southern Sweden

New sites of Mesoproterozoic granitoid magmatism in southern Sweden have been discovered by recent fieldwork and U-P zircon age determination. In the area around Stenshuvud, in eastern Skane, granitic melts were intruded into country-rock gneisses of unknown age at c. 1450 Ma. The 1458 6 Ma Stenshuvud intrusion is composed of several rock varieties including quartz monzonite, tonalite, monzogranit

The involvement of phospholipid:diacylglycerol acyltransferases in triacylglycerol production

We have characterized three CoA-independent types of enzyme, phospholipases, phospholipid:diacylglycerol acyltransferases (PDATs) and cholinephosphotransferases, responsible for the removal of unusual fatty acids from phosphatidylcholine (PC) in microsomal preparations from developing oil seeds. The metabolism of sn-2-[(14)C]acyl-PC was monitored in microsomal preparations from various oilseeds ha

Associations between markers of respiratory morbidity in European children

School-aged children often experience acute respiratory symptoms. In a multicentre European study, the association between chronic respiratory symptoms (reported in a questionnaire), skin-prick test results, and lung function, and the occurrence of acute respiratory morbidity, was examined among children aged 6-12 yrs with chronic respiratory symptoms. Children with chronic respiratory symptoms, l

Microfungi in coniferous forest soils treated with lime or wood ash

Microfungal species composition was studied in coniferous forest soils which had been treated with lime or wood ash. The pH increased by about 2.5 units at the highest rate of application. Fungi were isolated 4–5 years after the treatments using a soil washing technique. At one site, Öringe, clear differences in species composition due to liming were found. Penicillium spinulosum, Oidiodendron cf.

PYTHIA 6.4 physics and manual

The Pythia program can be used to generate high-energy-physics 'events', i.e. sets of outgoing particles produced in the interactions between two incoming particles. The objective is to provide as accurate as possible a representation of event properties in a wide range of reactions, within and beyond the Standard Model, with emphasis on those where strong interactions play a role, directly or ind

Compact difference methods applied to initial-boundary value problems for mixed systems.

An initial-boundary value problem to a system of nonlinear partial differential equations, which consists of a hyperbolic and a parabolic part, is taken into consideration, The problem is discretised by a compact finite difference method. An approximation of the numerical solution is constructed, at which the difference scheme is linearised. Nonlinear convergence is proved using the stability of t

Social mating systems and extrapair fertilizations in passerine birds

Two alternative hypotheses have been proposed to explain how social and genetic mating systems are interrelated in birds. According to the first (male trade-off) hypothesis, social polygyny should increase extrapair fertilizations because when males concentrate on attracting additional social mates, they cannot effectively protect females with whom the); have already paired from being sexually ass

Bose-Einstein-condensed atoms in toroidal traps

We consider Bose-Einstein-condensed atoms confined in a toroidal trap. Under conditions of one-dimensional behavior, the density distribution of the atoms may be exponentially localized or delocalized, even for very small variations in the trapping potential along the torus. For similar reasons, small irregularities of the trap may also have a very pronounced effect on the density of the cloud. Th

Ultrastructural immunolocalization of cartilage oligomeric matrix protein, thrombospondin-4, and collagen fibril size in rodent Achilles tendon in relation to exercise

Fourteen 3-week-old Sprague-Dawley rats were housed in pairs in standard cages (5 controls) and in individual cages with a running wheel. Four of these rats had run 27-36 km/week (low training-LT) and 5 had run 56-92 km/week (high training-HT). After 4 weeks, the rats were euthanized and Achilles tendons were fixed for electron microscopy. The ultrastructural distribution of cartilage oligomeric m

Breeding patterns of great tits (Parus major) in pine forests along the Portuguese west coast

The breeding biology of great tits (Parus major) was studied in two forests of maritime pine (Pinus pinaster) on the west coast of Portugal, 200 km apart: Leiria (north) and Apostica (south). These two forests are located in a transition zone between Atlantic climate in the north, and Mediterranean climate in the south. Breeding onset was, on average, in the second and third week of March, which a

Structural mechanism of plant aquaporin gating

Plants counteract fluctuations in water supply by regulating all aquaporins in the cell plasma membrane. Channel closure results either from the dephosphorylation of two conserved serine residues under conditions of drought stress, or from the protonation of a conserved histidine residue following a drop in cytoplasmic pH due to anoxia during flooding. Here we report the X-ray structure of the spi

Markers of high fish intake are associated with decreased risk of a first myocardial infarction

High intake of fish has been associated with reduced risk of CHD. The high content of n-3 polyunsaturated fatty acids (PUFA) in fish has been suggested to be a protective factor. In addition, fish is the entirely dominating source of methylmercury for the general population, and the concentration of Hg in erythrocytes (Ery-Hg) is often used as an index of fish consumption. Our aim was to study the

Kinins promote B2 receptor endocytosis and delay constitutive B1 receptor endocytosis.

Upon sustained insult, kinins are released and many kinin responses, such as inflammatory pain, adapt from a B2 receptor (B2R) type in the acute phase to a B1 receptor (B1R) type in the chronic phase. In this study, we show that kinins modulate receptor endocytosis to rapidly decrease B2R and increase B1R on the cell surface. B2Rs, which require agonist for activity, are stable plasma membrane com

Matrix metalloproteinase inhibitor BB-3103 unlike the serine proteinase inhibitor aprotinin abrogates epidermal healing of human skin wounds ex vivo.

Several matrix metalloproteinases and serine proteinases are upregulated in migrating keratinocytes during cutaneous wound repair. Single cell culture studies indicate the necessity for matrix metalloproteinases but not for serine proteinases in keratinocyte locomotion. To account for epithelial-mesenchymal interactions, an ex vivo human skin wound model was used to investigate the contribution of