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Ferrochelatase catalyzes the terminal step in the heme biosynthetic pathway, i.e., the incorporation of Fe(II) into protoporphyrin IX. Various biochemical and biophysical methods have been used to probe the enzyme for metal binding residues and the location of the active site. However, the location of the metal binding site and the path of the metal into the porphyrin are still disputed. Using sit

This paper presents a new design method for PID controllersbased on optimization of load disturbance rejection with constraintson robustness to model uncertainties. The design also deliversparameters to deal with measurement noise and set point response. Thus, theformulation of the design problem captures four essential aspects ofindustrial control problems, leading to a constrained optimizationpr

Presently there is no neuroprotective pharmacological treatment of proven clinical safety and efficacy available. The purpose of this study was to investigate whether the ss-carboline, abecarnil (Abe), which has already passed clinical phase III trials in patients with anxiety disorders, is neuroprotective in in vitro models of cerebral ischemia or excitotoxicity. Abe (100 nM) protected cultured c

A method is suggested which allows truncation of the virtual space in Cholesky decomposition-based multiconfigurational perturbation theory (CD-CASPT2) calculations with systematic improvability of the results. The method is based on a modified version of the frozen natural orbital (FNO) approach used in coupled cluster theory. The idea is to exploit the near-linear dependence among the eigenvecto

The Iberian Slug, Arion lusitanicus Mabille (Stylomatophora: Arionidae), has developed into a destructive pest in Swedish gardens and orchards over the past 10-20 years. Many attempts to eradicate this pest have been made using a variety of different methods. The aim of this study was to investigate the effectiveness of two different types of homemade traps made from simple, inexpensive materials

Antithrombin (AT) is a serine protease inhibitor that has thrombin, factors IXa and Xa as target proteases. In addition to active native AT, two other forms have been identified in plasma: the reactive center loop inserted cleaved and latent, uncleaved forms. Both have been shown to be present in normal human blood. Latent AT forms a dimer with native AT in vitro, thus inactivating the native form

Quantitative assessment of regional myocardial function at rest and during stress with Doppler tissue imaging (DTI) plays an important role in daily routine echocardiography. However, reliable visual analysis is largely dependent on image quality and adequate border delineation, which still remains a challenge in a significant number of patients. In this respect, an ultrasound contrast agent (UCA)

Objective. To evaluate trends in and risk factors for mortality among patients with rheumatoid arthritis (RA) over a 40-year period. Methods. A population-based inception cohort was assembled from among all Rochester, Minnesota residents ages greater than or equal to18 years who were first diagnosed with RA (fulfilling the 1987 American College of Rheumatology criteria for RA) between January 1, 1

The oxidation and dealkylation of dimethylsulfoxide (DMSO), dimethylsulfide (DMS), and trimethylamine (TMA) by cytochrome P450 has been studied with density functional theory calculations. The results show that the oxidation reactions always occur on the doublet spin surface, whereas dealkylations can take place for both the doublet and quartet spin states. Moreover, DMS is more reactive than DMSO

The effect of the anionic surfactant SDS (sodium dodecyl sulfate) on the adsorption behaviors of cationic hydroxyethyl celluloses (Polymer JR-125, JR-400, and JR-30M) and hydrophobically modified cationic cellulose (Quatrisoft LM-200) at silica surfaces in the presence of a 10 mM NaCl solution has been investigated by null ellipsometry. The adsorbed amount of LM-200 is found to be considerably lar

A number of corporate management tools have been developed during the last decades. This has given the impression that industry is in the lead for developing a more environmentally sound and sustainability-adopted future as concerns the production and the products they are working responsible from. This paper includes a short review of some key tools, including cleaner production assessments, life

Alkyl glycosides were synthesised from starch and alcohols using Aspergillus oryzae a-amylase as catalyst. In the degradation of starch by a-amylase, the alcohols competed with water as glycosyl acceptors. In the reaction with methanol, methyl maltoside and methyl maltotrioside were the main alcoholysis products. Conversion of 45 g/1 starch in 30% methanol resulted in a product mixture containing

Background: Noise is typically conceived of as being detrimental to cognitive performance. However, given the mechanism of stochastic resonance, a certain amount of noise can benefit performance. We investigate cognitive performance in noisy environments in relation to a neurocomputational model of attention deficit hyperactivity disorder (ADHD) and dopamine. The Moderate Brain Arousal model (MBA;

Soils contain highly diverse communities of microorganisms and invertebrates. The trophic interactions between these species are largely unknown. Collembolans form an abundant part of the invertebrate community in soils. A prevailing view is that soil collembolans are generalist feeders on fungi, lichens, fragmented litter and bacteria. However, in laboratory food choice experiments, it has been s

The business model concept is becoming increasingly popular within IS, management and strategy literature. It is used within many fields of research, including both traditional strategy theory and in the emergent body of literature on e-business. However, the concept is often used independently from theory, meaning model components and their interrelations are relatively obscure. Nonetheless, we b

Results of previous studies on fish intake and stroke risk have been inconclusive. Different stroke types have often not been separated. Our aim was to elucidate whether intake of fish, Hg or the sum of proportions of fatty acids EPA (20: 5n-3) and DHA (22: 6n-3) influence the risk of haemorrhagic or ischaemic stroke. Within a population-based cohort from a community intervention programme, 369 st

The contribution of lipoteichoic acid (LTA) to the hydrophobic surface properties of group A streptococci was investigated in aqueous dextran-polyethylene glycol two-phase systems. Enzymatic digestions were performed to characterize the hydrophobic surface structure. The results obtained indicated that LTA is a major factor responsible for the hydrophobic character of the cell surface of group A s

It is commonly observed that the rate of enzymatic hydrolysis of solid cellulose substrates declines markedly with time. In this work the mechanism behind the rate reduction was investigated using two dominant cellulases of Trichoderma reesei: exoglucanase Cel7A (formerly known as CBHI) and endoglucanase Cel7B (formerly EGI). Hydrolysis of steam-pretreated spruce (SPS) was performed with Cel7A and