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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

Mixed solutions of hydrophobically modified graft and block copolymers

Phase separation temperatures and viscosities of dilute and semidilute aqueous mixtures of hydrophobically modified graft and block copolymers have been studied. The graft copolymer was hydrophobically modified ethyl(hydroxyethyl)cellulose (HM-EHEC), and the block copolymers were hydrophobically modified poly(ethylene glycol) (HM-PEG) with diblock (DB) or triblock (TB) structures, i.e., modified a

Individualized low-dose growth hormone (GH) treatment in GH-deficient adults with childhood-onset disease: metabolic effects during fasting and hypoglycemia

Growth hormone (GH) has insulin-antagonistic effects, and GH secretion is augmented during fasting and hypoglycemia. In the present study, 10 patients aged 21 to 28 years with childhood-onset GH deficiency (GHD) were studied during a 24-hour fast and a hypoglycemic glucose clamp before and after 9 months of GH replacement. During the 24-hour fast, blood glucose, serum insulin, and serum free fatty

Young today-adult tomorrow! Studies on physical status, physical activity, attitudes, and self-perception in children and adolescents

The aim was to gain knowledge of young people's physical status and physical activity, and to further the understanding of the role of school physical education in a salutogenic public health perspective. Two studies were performed in southern Sweden. Study 1 was performed in 1996 among 301 adolescents aged 16-19 in upper secondary school. It comprised three parts: a questionnaire, seven physical

Knee arthroplasty in rheumatoid arthritis. A report from the Swedish Knee Arthroplasty Register on 4,381 primary operations 1985-1995

The Swedish Knee Arthroplasty Register has data on 4,381 primary operations performed 1985-1995 for rheumatoid arthritis. Of these, 192 were performed with unicompartmental prostheses and 4143 with tricompartmental. 77% were women and the mean age was 66 years. There were 126 first, 20 second, and 1 third revision in tricompartmental arthroplasties, mainly for loosening, infection and patellar pro

Isolation, crystallisation, and preliminary X-ray analysis of the bovine mitochondrial EF-Tu:GDP and EF-Tu:EF-Ts complexes

Previous studies have shown that when bovine mitochondrial elongation factor Ts (EF-Ts) is expressed in Escherichia coli, it forms a tightly associated complex with E. coli elongation factor Tu (EF-Tu). In contrast to earlier experiments, purification of free mitochondrial EF-Ts was accomplished under nondenaturing conditions since only about 60% of the expressed EF-Ts copurified with E. coli EF-T

Class dependent cluster refinement

Unsupervised classification is a very common problem in pattern recognition even when the classes are known. In many areas intra-class variations may be greater than the inter-class variations causing a need for a subdivision of the training set of a class into smaller subunits often referred to as clusters. The subdivision or clustering is often performed independently of the relative properties

OSL chronology for a sediment core from the southern Baltic Sea: A continuous sedimentation record since deglaciation

A chronology based on optically stimulated luminescence (OSL) dating is presented for the late- and post-glacial evolution of the southern Baltic Sea (-15ka to present). During this period, large water level and salinity changes occurred in the Baltic Basin due to opening and closing of connections to the North Atlantic. Previous attempts to establish a chronology for these palaeoenvironmental cha

Shining lights or lone wolves? Creativity and self-image in primary school children

The relationship between self-image and creativity was studied in primary school children. Earlier research points in two directions. Some researchers describe the creative child as well adjusted. Others provide a more nuanced picture in which less well-behaved children can also be creative. Three different measures of creativity were used in this study: the Unusual Uses Test, an activity question

Effect of inhaled fluticasone with and without salmeterol on airway inflammation in asthma

Background: The clinical benefit of combining long-acting beta(2)-agonists with inhaled corticosteroids rather than doubling the dose of corticosteroid has been well-documented. However, there are concerns that this might result in a masking of underlying airway inflammation. Objective: The aim of this study was to test the hypothesis that the addition of the long-acting beta(2)-agonist salmeterol

New information on b-delayed neutron emission from 12,14Be

The β-delayed neutron branches from neutron-rich Be-isotopes have been measured with a setup sensitive down to thermal energies. For 14Be a new value of Pn = 101 ± 4% has been found for the total neutron-emission probability and an upper limit of 2.4% (95% confidence level) is imposed on the combination P2n + 3P3n of multi-neutron emission probabilities. Moreover, an improved value of Pn = 0.50 ±

Recent changes in the marine environment in relation to climate, hydrography, and human impact –with special reference to fjords on the Swedish west coast

To obtain a perspective of changes occurring in the marine environment it is essential to study an area over a long time span. Doing so might also facilitate the understanding of the mechanisms and processes that govern a certain marine setting. In this thesis, changes in the pelagic and benthic environment during the last c. 200 years have been investigated in two fjords on the Swedish west coast

Slepian models and regression approximations in crossing and extreme value theory

In crossing theory for stochastic processes the distribution of quantities such as distances between level crossings, maximum height of an excursion between level crossings, amplitude and wavelength, etc., can only be written in the form of infinite-dimensional integrals, which are difficult to evaluate numerically. A Slepian model is an explicit random function representation of the process after