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The influence of axial ligands on the reduction potential of blue copper proteins

The reduction potentials of blue copper sites vary between 180 and about 1000 mV. It has been suggested that the reason for this variation is that the proteins constrain the distance between the copper ion and its axial ligands to different values. We have tested this suggestion by performing density functional B3LYP calculations on realistic models of the blue copper proteins, including solvent e

On the significance of hydrogen bonds for the discrimination between CO and O2 by myoglobin

Quantum chemical geometry optimisations have been performed on realistic models of the active site of myoglobin using density functional methods. The energy of the hydrogen bond between the distal histidine residue and CO or O2 has been estimated to be 8 kJ/mol and 32 kJ/mol, respectively. This 24 k J/mol energy difference accounts for most of the discrimination between CO and O2 by myoglobin (abo

On the role of strain in blue copper proteins

Theoretical investigations of the structure and function of the blue copper proteins are described. We have studied the optimum vacuum geometry of oxidised and reduced copper sites, the relative stability of trigonal and tetragonal Cu(II) structures, the relation between the structure and electronic spectra, the reorganisation energy, and reduction potentials. Our calculations give no support to t

The structure and function of blue copper proteins

Theoretical investigations of the structure and function of the blue copper proteins and the dimeric CuA site are described. We have studied the optimum vacuum geometry of oxidised and reduced copper sites, the relative stability of trigonal and tetragonal Cu(II) structures, the relation between the structure and electronic spectra, the reorganisation energy, and reduction potentials. We also comp

A Tetra-Nitrato Complex of Platinum(II), Synthesis and Crystal Structure of K2[Pt(NO3)4].1/2H2O

K2[Pt(NO3)4]·1/2H2O was prepared from ca 0.4 M solutions of platinum(II) perchlorate in perchloric acid by addition of KHCO3 and KNO3. Its crystal structure was determined from X-ray intensity data collected with a CAD-4 diffractometer. Monochromatic MoKα-radiation was used. The space group is I4/m with Z = 4; a = 7.5277(4) and c = 20.470(3) Å. The refinement converged to R = 0.036. The structure K2[Pt(NO3)4]·Full-size image (

Mechanistic Modeling of Reversed-Phase Chromatography of Insulins with Potassium Chloride and Ethanol as Mobile-Phase Modulators

The purpose of this study was to investigate the adsorption mechanism in reversed-phase chromatography (RPC) of proteins and to develop a model for the effect of dual mobile phase modulators—a salt and an organic solvent—on this process. Two different adsorption mechanisms were considered: (1) pure association of a protein molecule and one or more ligands and (2) displacement of the organic modula

The comparative and combined effects of hydrogen addition on the laminar burning velocities of methane and its blends with ethane and propane

Laminar burning velocities of hydrocarbon blends of relevance to natural gas combustion, with addition of 0, 10, 35 and 50% hydrogen, were measured using the heat flux method. Hydrocarbon blends were methane (80%)/ethane (20%), methane (80%)/propane (20%) and methane (80%)/ethane (10%)/propane (10%), and in addition experiments were performed using pure methane as a fuel. For the first time it was

Childhood leukaemia survivors' experiences of long-term follow-ups in an endocrine clinic – A focus-group study

The survival rate after childhood cancer has improved markedly and today more than 80% of patients will survive. Many childhood cancer survivors suffer from late complications due to radiotherapy and chemotherapy. Survivors of Acute Lymphoblastic Leukaemia (ALL), treated with cranial radiotherapy, are at a particularly high risk of having endocrine complications. Purpose To illuminate childhood AL

Electrochemical wiring of the Gram-positive bacterium Enterococcus faecalis with osmium redox polymer modified electrodes

The Gram-positive bacterium Enterococcus faecalis was investigated to test its ability to electrochemically communicate with electrodes. E. faecalis cells were successfully “wired” to gold electrodes through [Os(2,2′-bipyridine)2-poly(N-vinylimidazole)10Cl]2 +/+ redox polymer. Maximum current density achieved in response to 10 mM D-glucose was 18 ± 1 μA cm− 2. Control experiments without redox pol

Consistent elastoplastic cohesive zone model at finite deformations – Variational formulation

Cohesive zone models based on classical interface-type formulations at finite deformations are subjected to fundamental physical principles such as thermodynamical consistency, balance equations and material frame indifference. However, these restraints are often ignored and in that respect such formulations are inconsistent. By way of contrast, a consistent cohesive zone framework suitable for th

Foreign Institutional Investment, Ownership, and Liquidity : Real and Informational Frictions

The literature widely documents the negative liquidity impact of foreign participation in firms that permit high foreign institutional ownership. This paper employs a unique setting for the limited participation of qualified foreign institutional investors (QFIIs) in China's A-share market and examines how this impacts on stock liquidity in emerging markets. Contrary to the findings in the literat

Local and landscape drivers of arthropod diversity and decomposition processes in oil palm leaf axils

Oil palm expansion results in a loss of biodiversity and associated ecosystem services. However, there are factors that influence the severity of these impacts and enhancing biodiversity within plantations is important. In the present study, we examined the role of epiphytes for supporting arthropod communities in oil palm plantations in Sumatra, Indonesia. We considered the effects of landscape c

Divergence in stakeholders' preferences : Evidence from a choice experiment on forest landscapes preferences in Sweden

A great deal of biodiversity can be found in private forests, and protecting it requires taking into consideration the preferences of key stakeholders. In this study, we examine divergence in stakeholders' preferences for forest attributes across the general public, private non-industrial forest owners and public and private forest officials in Sweden by conducting a discrete choice experiment. Ou

The effect of forest owner decision-making, climatic change and societal demands on land-use change and ecosystem service provision in Sweden

The uncertain effects of climatic change and changing demands for ecosystem services on the distribution of forests and their levels of service provision require assessments of future land-use change, ecosystem service provision, and how ecosystem service demands may be met. We present CRAFTY-Sweden, an agent-based, land-use model that incorporates land owner behaviour and decision-making in model