Modelling and performance of an active heave compensator for offshore operations

The development of offshore oil and gas fields require the placement of different equipment on the sea floor. This is done by deploying the equipment from vessels operating in dynamic positioning on the surface. The deployment operation has different phases, and in higher sea states, it may require wave-load synchronization, when the load is going through the splash zone, and heave compensation when the load is close to the sea floor. In this paper, we analyse the performance of a particular type of hardware operating in a heave compensation mode. We derive a comprehensive model, analyse limits of performance and evaluate a control strategy.

Electropolymerisation of catalytically active PEDOT from an ionic liquid on a flexible carbon cloth using a sandwich cell configuration

We report the electropolymerization of poly(3,4-ethylenedioxythiopene) (PEDOT) from an ionic liquid, butyl-methylpyrrolidinium bis(trifluoromethanesulfonyl)imide (C4mpyrTFSI) onto flexible carbon cloth electrodes. A continuous, homogeneous and well adhered coating of the individual cloth fibres is achieved by employing a sandwich cell arrangement where the carbon cloth which is soaked with electrolyte is placed between two indium tin oxide electrodes isolated from each other by a battery separator. The resultant PEDOT modified carbon cloth electrode demonstrates excellent activity for the oxygen reduction reaction which is due to the doping level, conductivity and morphology of the PEDOT layer and is also tolerant to the presence of methanol in the electrolyte. This simple approach therefore offers a route to fabricate flexible polymer electrodes that could be used in various electronic applications.

Active aging: Exploration into self-ratings of "being active," out-of-home physical activity, and participation among older Australian adults living in four different settings

We examined whether self-ratings of “being active” among older people living in four different settings (major city high and lower density suburbs, a regional city, and a rural area) were associated with out-of-home participation and outdoor physical activity. A mixed-methods approach (survey, travel diary, and GPS tracking over a one-week period) was used to gather data from 48 individuals aged over 55 years. Self-ratings of “being active” were found to be positively correlated with the number of days older people spent time away from home but unrelated to time traveled by active means (walking and biking). No significant differences in active travel were found between the four study locations, despite differences in their respective built environments.The findings suggest that additional strategies to the creation of “age-friendly” environments are needed if older people are to increase their levels of outdoor physical activity. “Active aging” promotion campaigns may need to explicitly identify the benefits of walking outdoors to ambulatory older people as a means of maintaining their overall health, functional ability, and participation within society in the long-term and also encourage the development of community-based programs in order to facilitate regular walking for this group.

Generation of catalytically active materials from a liquid metal precursor

A facile route to prepare catalystically active materials from a galinstan liquid metal alloy is introduced. Sonicating liquid galinstan in alkaline solution or treating it in reducing media results in the creation of solid In/Sn rich microspheres that show catalytic activity toward both potassium ferricyanide and 4-nitrophenol reduction.

Hyperexpression of biologically active human chorionic gonadotropin using the methylotropic yeast, Pichia pastoris

Human chorionic gonadotropin (hCG), a heterodimeric glycoprotein hormone, is composed of an alpha subunit noncovalentlv associated with the hormone-specific beta subunit. The objective of the present study was recombinant expression of properly folded, biologically active hCG and its subunits using an expression system that could be used for structure-function studies while providing adequate quantities of the hormone for immunocontraceptive studies. We report here expression of biologically active hCG and its subunits using a yeast expression system, Pichia pastoris. The recombinant hGG alpha and hCG beta subunits were secreted into the medium and the levels of expression achieved at shake culture level were 24 and 2.7-3 mg/l secretory medium respectively. Go-expression of both subunits in the same cell resulted in secretion of heterodimeric hGG into the medium. The pichia-expressed hCG was immunologically similar to the native hormone, capable of binding to the LH receptors and stimulating a biological response in vitro. Surprisingly, the maximal response obtained was twice that obtained with the native hGG. The le level of expression of hCG achieved was 12-16 mg/l secretory medium and is expected to increase several-fold in a fermenter. Thus the Pichia expression system is capable of hyperexpressing properly folded, biologically active hGG and is suitable for structure-function studies of the hormone.

Use of semi-active dampers in seismic mitigation of building structures

This research provides information for providing the required seismic mitigation in building structures through the use of semi active and passive dampers. The Magneto-Rheological (MR) semi-active damper model was developed using control algorithms and integrated into seismically excited structures as a time domain function. Linear and nonlinear structure models are evaluated in real time scenarios. Research information can be used for the design and construction of earthquake safe buildings with optimally employed MR dampers and MR-passive damper combinations.

A theoretical model for the magnetic helicity of solar active regions

Active regions on the solar surface are known to possess magnetic helicity, which is predominantly negative in the northern hemisphere and positive in the southern hemisphere. Choudhuri et al. [Choudhuri, A.R. On the connection between mean field dynamo theory and flux tubes. Solar Phys. 215, 31–55, 2003] proposed that the magnetic helicity arises due to the wrapping up of the poloidal field of the convection zone around rising flux tubes which form active regions. Choudhuri [Choudhuri, A.R., Chatterjee, P., Nandy, D. Helicity of solar active regions from a dynamo model. ApJ 615, L57–L60, 2004] used this idea to calculate magnetic helicity from their solar dynamo model. Apart from getting broad agreements with observational data, they also predict that the hemispheric helicity rule may be violated at the beginning of a solar cycle. Chatterjee et al. [Chatterjee, P., Choudhuri, A.R., Petrovay, K. Development of twist in an emerging magnetic flux tube by poloidal field accretion. A&A 449, 781–789, 2006] study the penetration of the wrapped poloidal field into the rising flux tube due to turbulent diffusion using a simple 1-d model. They find that the extent of penetration of the wrapped field will depend on how weak the magnetic field inside the rising flux tube becomes before its emergence. They conclude that more detailed observational data will throw light on the physical conditions of flux tubes just before their emergence to the photosphere.

High-level expression of biologically active glycoprotein hormones in Pichia pastoris strains—selection of strain GS115, and not X-33, for the production of biologically active N-glycosylated 15N-labeled phCG

The methylotrophic yeast Pichia pastoris is widely used for the production of recombinant glycoproteins. With the aim to generate biologically active 15N-labeled glycohormones for conformational studies focused on the unravelling of the NMR structures in solution, the P. pastoris strains GS115 and X-33 were explored for the expression of human chorionic gonadotropin (phCG) and human follicle-stimulating hormone (phFSH). In agreement with recent investigations on the N-glycosylation of phCG, produced in P. pastoris GS115, using ammonia/glycerol-methanol as nitrogen/carbon sources, the N-glycosylation pattern of phCG, synthesized using NH4Cl/glucose–glycerol–methanol, comprised neutral and charged, phosphorylated high-mannose-type N-glycans (Man8–15GlcNAc2). However, the changed culturing protocol led to much higher amounts of glycoprotein material, which is of importance for an economical realistic approach of the aimed NMR research. In the context of these studies, attention was also paid to the site specific N-glycosylation in phCG produced in P. pastoris GS115. In contrast to the rather simple N-glycosylation pattern of phCG expressed in the GS115 strain, phCG and phFSH expressed in the X-33 strain revealed, besides neutral high-mannose-type N-glycans, also high concentrations of neutral hypermannose-type N-glycans (Manup-to-30GlcNAc2). The latter finding made the X-33 strain not very suitable for generating 15N-labeled material. Therefore, 15N-phCG was expressed in the GS115 strain using the new optimized protocol. The 15N-enrichment was evaluated by 15N-HSQC NMR spectroscopy and GLC-EI/MS. Circular dichroism studies indicated that 15N-phCG/GS115 had the same folding as urinary hCG. Furthermore, 15N-phCG/GS115 was found to be similar to the unlabeled protein in every respect as judged by radioimmunoassay, radioreceptor assays, and in vitro bioassays.

Structures and molecular-dynamics studies of three active-site mutants of bovine pancreatic phospholipase A(2)

Phospholipase A(2) hydrolyzes phospholipids at the sn-2 position to cleave the fatty-acid ester bond of L-glycerophospholipids. The catalytic dyad (Asp99 and His48) along with a nucleophilic water molecule is responsible for enzyme hydrolysis. Furthermore, the residue Asp49 in the calcium-binding loop is essential for controlling the binding of the calcium ion and the catalytic action of phospholipase A2. To elucidate the structural role of His48 and Asp49, the crystal structures of three active-site single mutants H48N, D49N and D49K have been determined at 1.9 angstrom resolution. Although the catalytically important calcium ion is present in the H48N mutant, the crystal structure shows that proton transfer is not possible from the catalytic water to the mutated residue. In the case of the Asp49 mutants, no calcium ion was found in the active site. However, the tertiary structures of the three active-site mutants are similar to that of the trigonal recombinant enzyme. Molecular-dynamics simulation studies provide a good explanation for the crystallographic results.

Amino acid sequence of the winged bean (Psophocarpus tetragonolobus) basic lectin. Adenine binding and identification of the active-site tryptophan residue

The complete amino acid sequence of winged bean basic agglutinin (WBA I) was obtained by a combination of manual and gas-phase sequencing methods. Peptide fragments for sequence analyses were obtained by enzymatic cleavages using trypsin and Staphylococcus aureus V8 endoproteinase and by chemical cleavages using iodosobenzoic acid, hydroxylamine, and formic acid. COOH-terminal sequence analysis of WBA I and other peptides was performed using carboxypeptidase Y. The primary structure of WBA I was homologous to those of other legume lectins and more so to Erythrina corallodendron. Interestingly, the sequence shows remarkable identities in the regions involved in the association of the two monomers of E. corallodendron lectin. Other conserved regions are the double metal-binding site and residues contributing to the formation of the hydrophobic cavity and the carbohydrate-binding site. Chemical modification studies both in the presence and absence of N-acetylgalactosamine together with sequence analyses of tryptophan-containing tryptic peptides demonstrate that tryptophan 133 is involved in the binding of carbohydrate ligands by the lectin. The location of tryptophan 133 at the active center of WBA I for the first time subserves to explain a role for one of the most conserved residues in legume lectins.

Cloning,overexpression and purification of functionally active Saccharomyces cerevisiae Hop1 protein from scherichia coli

One of the major limitations to the application of high-resolution biophysical techniques such as X-crystallography and spectroscopic analyses to structure-function studies of Saccharomyces cerevisiae Hop1 protein has been the non-availability of sufficient quantities of functionally active pure protein. This has, indeed, been the case of many proteins, including yeast synaptonemal complex proteins. In this study, we have performed expression screening in Escherichia coli host strains, capable of high-level expression of soluble S. cerevisiae Hop1 protein. A new protocol has been developed for expression and purification of S. cerevisiae Hop1 protein, based on the presence of hexa-histidine tag and double-stranded DNA-Cellulose chromatography. Recombinant S. cerevisiae Hop1 protein was >98% pure and exhibited DNA-binding activity with high-affinity to the Holliday junction. The availability of the recombinant HOP1 expression vector and active Hop1 protein would facilitate structure-function investigations as well as the generation of appropriate truncated and site-directed mutant proteins, respectively. (C) 2010 Elsevier Inc. All rights reserved.

Moral Education in the Japanese Primary School Curricular Revision at the Turn of the Twenty-first Century: Aiming at a Rich and Beautiful Kokoro

This study examines values education in Japanese schools at the beginning of the millennium. The topic was approached by asking the following three questions concerning the curricular background, the morality conveyed through textbooks and the characterization of moral education from a comparative viewpoint: 1) What role did moral education play in the curriculum revision which was initiated in 1998 and implemented in 2002? 2) What kinds of moral responsibilities and moral autonomy do the moral texts develop? 3) What does Japanese moral education look like in terms of the comparative framework? The research was based on curriculum research. Its primary empirical data consisted of the national curriculum guidelines for primary school, which were taken into use in 2002, and moral texts, Kokoro no nôto, published by the Ministry of Education in the same context. Since moral education was approached in the education reform context, the secondary research material involved some key documents of the revision process from the mid-1990s to 2003. The research material was collected during three fieldwork periods in Japan (in 2002, 2003 and 2005). The text-analysis was conducted as a theory-dependent qualitative content analysis. Japanese moral education was analyzed as a product of its own cultural tradition and societal answer to the current educational challenges. In order to understand better its character, secular moral education was reflected upon from a comparative viewpoint. The theory chosen for the comparative framework, the value realistic theory of education, represented the European rational education tradition as well as the Christian tradition of values education. Moral education, which was the most important school subject at the beginning of modern school, was eliminated from the curriculum for political reasons in a school reform after the Second World War, but has gradually regained a stronger position since then. It was reinforced particularly at the turn of millennium, when a curriculum revision attempted to respond to educational and learning problems by emphasizing qualitative and value aspects. Although the number of moral lessons and their status as a non-official-subject remained unchanged, the Ministry of Education made efforts to improve moral education by new curricular emphases, new teaching material and additional in-service training possibilities for teachers. The content of the moral texts was summarized in terms of moral responsibility in four moral areas (intrapersonal, interpersonal, natural-supranatural and societal) as follows: 1) continuous self-development, 2) caring for others, 3) awe of life and forces beyond human power, and 4) societal contribution. There was a social-societal and emotional emphasis in what was taught. Moral autonomy, which was studied from the perspectives of rational, affective and individuality development, stressed independence in action through self-discipline and responsibility more than rational self-direction. Japanese moral education can be characterized as the education of kokoro (heart) and the development of character, which arises from virtue ethics. It aims to overcome egoistic individualism by reciprocal and interdependent moral responsibility based on responsible interconnectedness.

Identification of the active-site peptide of 2,3-dihydroxybenzoic acid decarboxylase from Aspergillus oryzae

The non-oxidative decarboxylation of aromatic acids is a poorly understood reaction. The transformation of 2,3-dihydroxybenzoic acid to catechol in the fungal metabolism of indole is a prototype of such a reaction. 2,3-Dihydroxybenzoic acid decarboxylase (EC 4.1.1.46) which catalyzes this reaction was purified to homogeneity from anthranilate induced cultures of Aspergillus oryzae using affinity chromatography. The enzyme did not require cofactors like NAD(+), PLP, TPP or metal ions for its activity. There was no spectral evidence for the presence of enzyme bound cofactors. The preparation, which was adjudged homogeneous by the criteria of SDS-PAGE, sedimentation analysis and N-terminal analysis, was characterized for its physicochemical and kinetic parameters. The enzyme was inactivated by group-specific modifiers like diethyl pyrocarbonate (DEPC) and N-ethylmaleimide (NEM). The kinetics of inactivation by DEPC suggested the presence of a single class of essential histidine residues, the second order rate constant of inactivation for which was 12.5 M(-1) min(-1). A single class of cysteine residues was modified by NEM with a second order rate constant of 33 M(-1) min(-1). Substrate analogues protected the enzyme against inactivation by both DEPC and NEM, suggesting the Location of the essential histidine and cysteine to be at the active site of the enzyme. The incorporation of radiolabelled NEM in a differential labelling experiment was 0.73 mol per mol subunit confirming the presence of a single essential cysteine per active-site. Differentially labelled enzyme was enzymatically cleaved and the peptide bearing the label was purified and sequenced. The active-site peptide LLGLAETCK and the N-terminal sequence MLGKIALEEAFALPRFEEKT did not bear any similarity to sequences reported in the Swiss-Prot Protein Sequence Databank, a reflection probably of the unique primary structure of this novel enzyme. The sequences reported in this study will appear in the Swiss-Prot Protein Sequence Databank under the accession number P80402.