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A short review on SSF - an interesting process option for ethanol production from lignocellulosic feedstocks.

ABSTRACT: Simultaneous saccharification and fermentation (SSF) is one process option for production of ethanol from lignocellulose. The principal benefits of performing the enzymatic hydrolysis together with the fermentation, instead of in a separate step after the hydrolysis, are the reduced end-product inhibition of the enzymatic hydrolysis, and the reduced investment costs. The principal drawba

The spatial tuning of achromatic and chromatic vision in budgerigars

Birds are assumed to use half of their cones (double cones) to detect fine spatial detail while their other half (single cones) is used for color vision. However, the spatial resolution of the color pathway in birds has never been studied. We determined the spatial contrast sensitivity to achromatic and isoluminant red-green and blue-green color gratings in budgerigars (Melopsittacus undulatus). C

Thermodynamic and kinetic characterization of host-guest association between bolaform surfactants and alpha- and beta-cyclodextrins

The thermodynamics and kinetics of formation of host-guest complexes between a series of bolaform surfactants of type C(n)Me(6)(2+)2Br(-) (n = 8, 10, and 12) and alpha-cyclodextrin and beta-cyclodextrin were studied with the aid of isothermal titration calorimetry (ITC) at 298.15 and 308.20 K. The association constant, the enthalpy, and the entropy of formation were determined. The obtained thermo

STIM evaluation in GeoPIXE to complement the quantitative dynamic analysis

The GeoPIXE software for quantitative PIXE trace element imaging and analysis is a well established package for evaluation of characteristic X-ray data for both PIXE and SXRF. For the case of microbeam applications on semi-thick samples knowledge of the local areal density distribution is important for precise quantification. A technique is reported to achieve this using the measurement of beam pa

Spjuten från Uppåkra : ritualförstörda eller förbrukade?

The spears from Uppåkra – ritually destroyed or worn out? : A collection of spearheads excavated at Uppåkra, Uppåkra parish in Scania has, although found in the middle of a settlement, been interpreted as a sacrificial deposit. The damage visible on several spearheads has been attributed to ritual destruction. This paper aims to show that the damage may have been sustained through use, without any

Self-employment of immigrants and natives in Sweden - a multilevel analysis

Recent research suggests that self-employment among immigrants is due to a combination of multiple situational, cultural and institutional factors, all acting together. Using multilevel regression and unique data on the entire population of Sweden for the year 2007, this study attempts to quantify the relative importance for the self-employed of embeddedness in ethnic contexts (country of birth) a

Terrestrial Gross Carbon Dioxide Uptake: Global Distribution and Covariation with Climate

Terrestrial gross primary production (GPP) is the largest global CO2 flux driving several ecosystem functions. We provide an observation-based estimate of this flux at 123 +/- 8 petagrams of carbon per year (Pg C year(-1)) using eddy covariance flux data and various diagnostic models. Tropical forests and savannahs account for 60%. GPP over 40% of the vegetated land is associated with precipitatio

On the well-posedness of the Maxwell system for linear bianisotropic media

The time dependent Maxwell system is supplemented with the constitutive relations of linear bianisotropc media and is treated as a neutral integro-differential equation in a Hilbert space. By using the theory of abstract Volterra equations and strongly continuous semigroups we obtain general well-posedness results for the corresponding mathematical problem.

Convergence of QM/MM free-energy perturbations based on molecular-mechanics or semiempirical simulations.

Lately, there has been great interest in performing free-energy perturbation (FEP) at the combined quantum mechanics and molecular mechanics (QM/MM) level, e.g. for enzyme reactions. Such calculations require extensive sampling of phase space, which typically is prohibitive with density-functional theory or ab initio methods. Therefore, such calculations have mostly been performed with semiempiric

LiZn4 - x (x = 0.825) as a (3 + 1)-dimensional modulated derivative of hexagonal close packing.

The (3+1)-dimensional modulated structure of the LiZn4 - x (x = 0.825) binary compound has been determined in the superspace. The compound crystallizes in the orthorhombic superspace group Cmcm(α00)0s0 with a = 2.7680 (6), b = 4.7942 (6), c = 4.3864 (9) Å, modulation wavevector: q ≃ 4/7a*. The structure is a derivative from the hexagonal close packing. The cubo-octahedron as a coordination polyhed

Effects of influenza A virus infection on migrating mallard ducks

The natural reservoir of influenza A virus is waterfowl, particularly dabbling ducks (genus Anas). Although it has long been assumed that waterfowl are asymptomatic carriers of the virus, a recent study found that low-pathogenic avian influenza (LPAI) infection in Bewick's swans (Cygnus columbianus bewickii) negatively affected stopover time, body mass and feeding behaviour. In the present study,

Early diphtheria-tetanus-pertussis vaccination associated with higher female mortality and no difference in male mortality in a cohort of low birthweight children: an observational study within a randomised trial

Background Studies from low-income countries have suggested that diphtheria-tetanus-pertussis (DTP) vaccine provided after Bacille Calmette-Guerin (BCG) vaccination may have a negative effect on female survival. The authors examined the effect of DTP in a cohort of low birthweight (LBW) infants. Methods 2320 LBW newborns were visited at 2, 6 and 12 months of age to assess nutritional and vaccinati

Submersion, accidental hypothermia and cardiac arrest, mechanical chest compressions as a bridge to final treatment: a case report

Three young men were trapped in a car at the bottom of a canal at two meters depth, after losing control of their vehicle. They were brought up by rescue divers and found in cardiac arrest. One of three patients had return of spontaneous circulation (ROSC), at 47 min after the accident. This sole survivor had the longest submersion time of the three and he received continued mechanical chest compr

Nontypeable Haemophilus influenzae Protein E Binds Vitronectin and Is Important for Serum Resistance

Nontypeable Haemophilus influenzae (NTHi) commonly causes local disease in the upper and lower respiratory tract and has recently been shown to interfere with both the classical and alternative pathways of complement activation. The terminal pathway of the complement system is regulated by vitronectin that is a component of both plasma and the extracellular matrix. In this study, we identify prote

Radiative lifetimes, branching fractions and oscillator strengths of some odd-parity levels in Ru I

Radiative lifetime measurements have been performed for six odd-parity levels of Ru I using a time-resolved laser-induced fluorescence technique. Branching fractions of seven odd-parity levels were also measured using a grating spectrometer with a hollow-cathode lamp. The results of lifetimes and branching fractions obtained here are combined to determine the absolute oscillator strengths of 25 li