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Dynamics of protein and peptide hydration

Biological processes often involve the surfaces of proteins, where the structural and dynamic properties of the aqueous solvent are modified. Information about the dynamics of protein hydration can be obtained by measuring the magnetic relaxation dispersion (MRD) of the water 2 H and 17 0 nuclei or by recording the nuclear Overhauser effect (NOE) between water and protein protons. Here, we use the

Highly diastereoselective hydrogenations leading to ß-hydroxy ∂-lactones in hydroxy-protected form. A modified view of ∂-lactone conformations.

Enol MEM ethers 4 and 15 and the corresponding enol acetates were hydrogenated over Pd/C with very high (>99%) diastereoselectivity to saturated -lactones. A stereochemical generalization can be formulated thus: trans-5,6-disubstituted 1-oxa-3-cyclohexen-2-ones (e.g. 14 and 15) are hydrogenated over Pd with high selectivity from the side trans to the C(6)-substituent. A mechanistic rationalization

Palearctic Sympiesis acalle and Sympiesis gordius (Hymenoptera : Eulophidae) in North America: Taxonomic changes and a review of Nearctic host records

The Palearctic eulophids, Sympiesis acalle (Walker) and S. gordius (Walker), are widespread in North America where they have been known as S. bimaculatipennis Girault and S. marylandensis Girault. respectively. To update their taxonomy, we have established seven new synonyms: Astichus bimaculatipennis Girault, Sympiesis bimaculata Crawford, and S. meteori Girault = S. acalle (Walker); and, S. mary

NIKE: a new clinical tool for establishing levels of indications for cataract surgery

Purpose: The purpose of this study was to construct a new clinical tool for establishing levels of indications for cataract surgery, and to validate this tool. Methods: Teams from nine eye clinics reached an agreement about the need to develop a clinical tool for setting levels of indications for cataract surgery and about the items that should be included in the tool. The tool was to be called 'N

Influence of ignition sources on heat release rate in the furniture calorimeter

When measuring the production rates of heat and smoke of upholstered furniture the ignition source must not influence the test results. In this paper variations in the strength, application time and geometry of the ignition burner used in the furniture calorimeter are studied. Results from replicate furniture calorimeter chair test show that the burning behaviour is almost independent of the burne

Evaluation and Mitigation of Industrial Fire Hazards

Popular Abstract in Swedish Ett beräkningsprogram, "FREIA", lämpligt för industriell brandriskanalys presenteras. Programmet beräknar skada på människor inom och utom en byggnad på grund av en brand eller ett utsläpp av farligt gods. För några av de i riskanalysen ingående momenten har ytterligare forskning utförts. Dessa områden är: Detektion, Släckmedel samt Brännskada på människa. Det är i dagA tool suitable for conducting industrial fire and explosion hazard analysis is presented, together with an identification of weak links in the hazard evaluation chain. For some of the weak links additional research has been carried out. The tool, "FREIA", evaluates the consequences for humans and components due to fires and accidental releases indoors and outdoors using established engineering m

Morphine metabolism after major liver surgery.

BACKGROUND: Impaired metabolism of morphine may lead to an increase in sedation and respiratory depression. METHODS: In the present study we investigated morphine pharmacokinetics in patients who had undergone liver resection (n = 15) compared to a control group undergoing colon resection (n = 15). Morphine was administered IV by patient-controlled analgesia. Plasma concentrations of morphine, mor

Minimization of the chromatic dispersion over a broad wavelength range in a single-mode optical fiber

The effective refractive index as a function of vacuum wavelength is approximated by Lagrange interpolation polynomials. The rms value of the chromatic dispersion is then calculated analytically. It is demonstrated that use of fourth-degree polynomials is far more efficient than the use of second-degree polynomials. The rms value of the chromatic dispersion over the wavelength range (1.25 mum, 1.6

Perspectives on Regional and Industrial Dynamics of Innovation

This thesis consists of five essays in the field of innovation economics, with an introductory chapter. The focus is mainly empirical with four of the five chapters consisting of studies of aspects of Swedish innovation activity. These empirical chapters are an endeavor to quantify aspects of the effects of the public -good property of knowledge. To this effect, innovation indicators were collecte

Internal fixation of femoral neck fractures in Parkinson's disease. 32 patients followed for 2 years

32 patients, suffering from Parkinson's disease, had internal fixation of femoral neck fractures. In 24 displaced fractures, 6 nonunions and 3 segmental collapses were seen; and in 8 undisplaced fractures, 1 case of segmental collapse was diagnosed. Healing complications were thus seen in one third. Total hip replacement for healing complication was performed in 3 of 32 patients. 9 patients died w

Temporal Aspects of High-Intensity Laser-Matter Interactions

Popular Abstract in Swedish Utvecklingen av laserpulser med extremt hög intensitet har försett forskare med ett verktyg som gör det möjligt att studera vad som händer då dessa pulser växelverkar med olika slags materia. Då växelverkan sker med en gas kan till exempel ultrakorta pulser från ultraviolett till röntgenområdet genereras som övertoner till laserpulsen. Dessa övertoner kan göras kortare The availability of short-pulse, high-intensity lasers has opened doors to new areas in atomic and plasma physics. The short pulses (a few femtoseconds), that are available today, enable unprecedented temporal measurements, while the high peak power accessible (several terawatts) allows physicists to study the interaction between light and relativistic plasmas. The aim of this work was twofold: i)

Partial resistance to malonate-induced striatal cell death in transgenic mouse models of Huntington's disease is dependent on age and CAG repeat length

Transgenic Huntington's disease (HD) mice, expressing exon 1 of the HD gene with an expanded CAG repeat, are totally resistant to striatal lesion induced by excessive NMDA receptor activation. We now show that striatal lesions induced by the mitochondrial toxin malonate are reduced by 70-80% in transgenic HD mice compared with wild-type littermate controls. This occurred in 6- and 12-week-old HD m

Neutrophil gelatinase-associated lipocalin is up-regulated in human epithelial cells by IL-1 beta, but not by TNF-alpha

Synthesis of the antimicrobial protein neutrophil gelatinase-associated lipocalin (NGAL) increases dramatically in bronchial epithelial cells and alveolear type II pneumocytes during lung inflammation. IL-1beta induces a >10-fold up-regulation of NGAL expression in the type II pneumocyte-derived cell line A549 cells, whereas TNF-alpha, IL-6, and LPS had no effect. Similar IL-1beta selectivity was

Genome-wide structural and functional protein characterization by ab initio protein structure prediction

Popular Abstract in Swedish Många av alla kemiska processer som pågår i våra kroppar utförs av proteiner. När de inte fungerar blir vi sjuka. I vissa fall, till exempel vid Alzheimers sjukdom eller Creutzfeld Jacobs sjukdom, beror det på att ett visst protein har fel form. Att förstå hur proteiner antar sin slutliga form och vad det har för inverkan på proteinets funktion är således viktigt. ÅVery little is known about a considerable part of all proteins and it is time consuming and expensive to study each individual protein to determine its function, structure and cellular role. Proteins retain structural, functional and sequential characteristics from ancestral proteins and hence two proteins that share a common ancestor, i.e. are homologs, will to some extent have similar sequen