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Eurasian ice-sheet interaction in northwestern Russia throughout the late Quaternary

Sediment successions from the Kanin Peninsula and Chyoshskaya Bay in northwestern Russia contain information on the marginal behaviour of all major ice sheets centred in Scandinavia, the Barents Sea and the Kara Sea during the Eemian - Weichselian. Extensive luminescence dating of regional lithostratigraphical units, supported by biostratigraphical evidence, identifies four major ice advances at 1

Human tissue kallikrein 5 is a member of a proteolytic cascade pathway involved in seminal clot liquefaction and potentially in prostate cancer progression

Human tissue kallikreins (hKs) are a family of fifteen serine proteases. Several lines of evidence suggest that hKs participate in proteolytic cascade pathways. Human kallikrein 5 (hK5) has trypsin-like activity, is able to self-activate, and is co-expressed in various tissues with other hKs. In this study, we examined the ability of hK5 to activate other hKs. By using synthetic heptapeptides that

Evidence of airway inflammation and remodeling in ski athletes with and without bronchial hyperresponsiveness to methacholine

Asthma-like symptoms, methacholine hyperresponsiveness, and use of asthma medication are prevalent in elite cross-country skiers. We quantitated mucosal inflammatory cell infiltration and tenascin expression in the subepithelial basement membrane in endobronchial biopsy specimens of the proximal airways from 40 elite, competitive skiers (mean: 17.5; range: 16 to 20 yr) without a diagnosis of asthm

Sensitivity of an ecosystem model to hydrology and temperature

We tested the sensitivity of a dynamic ecosystem model (LPJ-GUESS) to the representation of soil moisture and soil temperature and to uncertainties in the prediction of precipitation and air temperature. We linked the ecosystem model with an advanced hydrological model (JULES) and used its soil moisture and soil temperature as input into the ecosystem model. We analysed these sensitivities along a

Towards artificial photosynthesis: ruthenium-manganese chemistry for energy production

The synthesis and characterisation of supramolecular model systems mimicking the light reactions on the donor side of Photosystem II (PSII) in green plants have been reviewed. In these systems, manganese complexes and tyrosine are electron donors, modelling the manganese cluster and tyrosineZ in PSII. The donors have been covalently linked to a photosensitizer, a ruthenium(ii) tris-bipyridyl compl

Stability of immobilized Candida antarctica lipase B during chemo-enzymatic epoxidation of fatty acids

The parameters affecting the lipase activity and operational lifetime during chemo-enzymatic epoxidation of fatty acids were investigated. Immobilized Candida antarctica lipase B (Novozym (R) 435) was incubated in the presence of various reaction components (i.e. toluene, water, H2O2, oleic acid, perpalmitic acid, and epoxystearic acid, respectively) at temperatures between 20 and 60 degrees C fol

New experimental setup to use ellipsometry to study liquid-liquid and liquid-solid interfaces

Different types of optical light guides were constructed and tested to enable convenient multiple angle of incidence ellipsometry, on solid and liquid interfaces in liquid solutions. Two light guides are needed on an ellipsometer, one to guide the incoming light and one to guide the light that is reflected at the test surface, and therefore one light guide was mounted on the laser arm and one on t

Interstitial photodynamic therapy - diagnostic measurements and treatment in rat malignant experimental tumours

A recently developed multiple fibre system for treating malignant tumours with interstitial photodynamic therapy was used in studies on rats with colon adenocarcinoma inoculated into the muscles of the hind legs. The animals were intraperitonially administrated delta -aminolevulinic acid (ALA), which is metabolised to protoporphyrin IX (PpIX) in the tissue. The treatment system consists of a laser

Oligomerization of amyloid A beta(16-22) peptides using hydrogen bonds and hydrophobicity forces

The 16 - 22 amino-acid fragment of the beta-amyloid peptide associated with the Alzheimer's disease, Abeta, is capable of forming amyloid fibrils. Here we study the aggregation mechanism of Abeta(16-22) peptides by unbiased thermodynamic simulations at the atomic level for systems of one, three, and six Abeta(16-22) peptides. We find that the isolated Abeta(16-22) peptide is mainly a random coil i

Physico-chemical properties of the N-terminally truncated L68Q cystatin C found in amyloid deposits of brain haemorrhage patients.

Cystatin C, a major extracellular cysteine proteinase inhibitor, is deposited as amyloid in brain haemorrhage patients with hereditary cystatin C amyloid angiopathy (HCCAA). A disease-causing mutation on the genetic level results in the substitution Leu68-->Gln (L68Q) in cystatin C, which causes protein instability. Besides carrying the L68Q substitution, cystatin C in amyloid deposits isolated fr

Measurement of total and unilateral renal blood flow by oblique-angle velocity-encoded 2D-cine magnetic resonance angiography.

Two independent measurements of total renal blood flow (RBF) were made in healthy human subjects (n = 14, mean age 30 yr) by CINE phase-contrast magnetic resonance angiography. RBF, measured by summing the flows measured in the right and left renal arteries, was 1152 ± 44 ml/min (mean ± SE). RBF, measured from the difference between supra- and infrarenal abdominal aorta flow, was 1109 ± 68 ml/min.

Transmetallation reactions involving group 10 metals

This review gives an overview of the early development of transmetallation reactions for synthetic purposes and presents some recent results on the transmetallation reaction as a part of cross-coupling reactions and the mechanism of these reactions.

Bcl-2 but not FOXP1, is an adverse risk factor in immunochemotherapy-treated non-germinal center diffuse large B-cell lymphomas

Non-germinal center (non-GC) phenotype, high level expression of the transcription factor forkhead box protein P1 (FOXP1) and anti-apoptotic protein Bcl-2 have been identified as unfavorable prognostic factors for diffuse large B-cell lymphoma (DLBCL) patients treated with chemotherapy. Our aim was to re-evaluate the prognostic impact of these biologic factors on the survival of the patients treat

Exposure to PCB and p,p '-DDE in European and Inuit populations: impact on human sperm chromatin integrity

BACKGROUND: Persistent organochlorine pollutants ( POP), such as polychlorinated biphenyls (PCB) and dichlorodiphenyldichloroethylene (p,p'-DDE), are widely found in the environment and considered potential endocrine-disrupting compounds (EDC). Their impact on male fertility is still unknown. METHODS: To explore the hypothesis that POP is associated with altered sperm chromatin integrity, a cross-

Degradation of macromolecules by micro-fungi isolated from different podzolic soil horizons

The abilities of 60 species of soil microfungi to decompose protein, xylan. cellulose. and chitin were tested with an agar diffusion technique. Proteolytic capacity was shown by 51 species; 35 were xylanolytic, 31 were cellulolytic, and 23 were chitinolytic. The importance of the physiological capacities of soil fungi in determining the communities in different soil horizons is discussed.

Surface-plasmon-enhanced optical forces in silver nanoaggregates

We use extended Mie theory to investigate optical forces induced by and acting on small silver nanoparticle aggregates excited at surface plasmon resonance. It is shown that single molecules can be trapped at junctions between closely spaced nanoparticles, which are simultaneously pulled together by optical forces. These effects could significantly influence surface-enhanced Raman scattering and r

Influence of microbial species on small intestinal myoelectric activity and transit in germ-free rats

The effect of an intestinal microflora consisting of selected microbial species on myoelectric activity of small intestine was studied using germ-free rat models, with recording before and after specific intestinal colonization, in the unanesthetized state. Intestinal transit, neuropeptides in blood (RIA), and neuromessengers in the intestinal wall were determined. Clostridium tabificum vp 04 prom

Morphometric diversity and geographic differentiation in six dogrose taxa (Rosa Sect. Caninae, Rosaceae) from the Nordic countries

The dogroses (Rosa Sect. Caninae) are characterized by a unique meiosis - the canina meiosis - that results in restricted recombination. In the present study, we investigate population differentiation and morphometric diversity within six taxa, of Nordic dogroses, with the help of automated image analysis of leaflet shape and manually-measured reproductive characters. The total morphometric divers