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Does autochthonous primary production drive variability in bacterial metabolism and growth efficiency in lakes dominated by terrestrial C inputs?
During the past 20 yr, aquatic microbiologists have reported 2 strong patterns which initially appear contradictory. In pelagic systems, bacterial growth and biomass is well correlated with the growth and biomass of primary producers. However, bacterial respiration often exceeds net primary production, which suggests that bacteria are subsidized by external inputs of organic matter. We hypothesize
More physician consultations and antibiotic prescriptions in families with high concern about infectious illness-adequate response to infection-prone child or self-fulfilling prophecy?
Background. Respiratory tract infections (RTI) in children is the most common cause of prescription of antibiotics. It is important to describe and analyse non-medical factors in order to develop more rational use of antibiotics. Objectives. To compare families with high and low concern about infectious illness with regard to social variables, perception of infection proneness and beliefs in antib
Optical and mass spectrometric study of the pyrolysis gas of wood particles
A detailed experimental investigation has been made of the pyrolysis-the first step in biomass combustion-of single birchwood particles. In addition to mass spectrometric and gravimetric analysis, the pyrolysis volatiles were characterized by different optical techniques. Absorption measurements showed a nearly featureless absorption in the ultraviolet spectral region with a continuously stronger
Expression of sphingosine kinase gene in the interactions between human gastric carcinoma cell and vascular endothelial cell
AIM: To study the interactions between human gastric carcinoma cell (HGCC) and human vascular endothelial cell (HVEC), and if the expression of sphingosine kinase (SPK) gene was involved in these interactions. METHODS: The specific inhibitor to SPK, dimethyl sphingosine (DMS), was added acting on HGCC and HVEC, then the cell proliferation was measured by MTT. The conditioned mediums (CMs) of HGCC
445 A simple and fast multi leaf calibration method
P-selectin glycoprotein ligand-1 regulates chemokine-dependent leukocyte recruitment in colonic ischemia-reperfusion.
Objective and design: Leukocyte recruitment is a key feature in ischemia-reperfusion (I/R) -provoked tissue injury. This study evaluated the role of P-selectin-glycoprotein ligand-1 (PSGL-1) in CXC chemokine- and ischemia-reperfusion- induced leukocyte rolling and adhesion in the colon. Materials Balb/c mice were used in an inverted intravital fluorescence microscopy study of the microvascular bed
Mechanism of action of A-769662, a valuable tool for activation of AMP-activated protein kinase
We have studied the mechanism of A- 769662, a new activator of AMP- activated protein kinase ( AMPK). Unlike other pharmacological activators, it directly activates native rat AMPK by mimicking both effects of AMP, i. e. allosteric activation and inhibition of dephosphorylation. We found that it has no effect on the isolated alpha subunit kinase domain, with or without the associated autoinhibitor
Interleukin-4 increases murine airway response to kinins, via up-regulation of bradykinin B1-receptors and altered signalling along mitogen-activated protein kinase pathways.
A kind of auditory 'primitive intelligence' already present at birth
'Primitive intelligence' in audition refers to the capacity of the auditory system to adaptatively model the acoustic regularity and react neurophysiologically to violations of such regularity, thus supporting the ability to predict future auditory events. In the present study, event-related brain potentials to pairs of tones were recorded in 11 human newborns to determine the infants' ability to
Gondwanan floristic and sedimentological trends during the Permian-Triassic transition: new evidence from the Amery Group, northern Prince Charles Mountains, East Antarctica
The Permian-Triassic boundary within the Amery Group of the Lambert Graben is placed at the contact between the Bainmedart Coal Measures and overlying Flagstone Bench Formation, based on the first regular occurrence of Lunatisporites pellucidus and the first appearance of Aratrisporites and Lepidopteris species. The Permian-Triassic boundary is marked by the extinction of glossopterid and cordaita
A comparison of thermally and photochemically cross-linked polymers for nanoimprinting
The characteristics and benefits of two types of cross-linking prepolymers with low glass transition temperature (T-g) for nanoimprinting are reported. They are soluble in organic solvents and their solutions can be processed like those of common thermoplastics. The imprinted patterns receive high thermal and mechanical stability through cross-linking polymerization. The course of the polymerizati
Assessment of the environmental contamination with long-lived radionuclides around an operating RBMK reactor station
The presence of man-made gamma emitting radionuclides in the region within 32 km radius of the Ignalina NPP/Lithuania has been investigated during the period 2001-2004, prior to the closure of the first 4 the two operating RBMK 1500-type reactors. Gamma spectrometric measurements of various terrestrial and aquatic plants as well as of soil samples showed moderate environmental contamination with t
Imaging in cell-based therapy for neurodegenerative diseases.
Fetal cell transplantation for the treatment of Parkinsonrsquos and Huntingtonrsquos diseases has been developed over the past two decades and is now in early clinical testing phase. Direct assessment of the graftrsquos survival, integration into the host brain and impact on neuronal functions requires advanced in vivo neuroimaging techniques. Owing to its high sensitivity, positron emission tomog
Serum calcium and breast cancer risk: results from a prospective cohort study of 7,847 women.
Experimental and epidemiological studies suggest that calcium-regulating hormones-parathyroid hormone (PTH) and vitamin D-may be associated with breast cancer risk. No prospective cohort study has investigated the association between pre-diagnostic calcium levels and subsequent risk of breast cancer. We have examined this in a cohort of 7,847 women where serum calcium levels and established risk f
Streptococcus pyogenes expressing M and M-like surface proteins are phagocytosed but survive inside human neutrophils.
Increased aeolian activity during humidity shifts as recorded in a raised bog in south-west Sweden during the past 1700 years
Analyses of testate amoebae and aeolian sediment influx (ASI) were used to reconstruct effective humidity changes and aeolian activity in the coastal zone of south-west Sweden. Cores were taken from an ombrotrophic peat sequence from the Undarsmosse bog. Since both types of analysis were carried out on the same core, a direct comparison between humidity fluctuations in the bog and aeolian activity
Structural and energetic characteristics of the heparin-binding site in antithrombotic protein C
Human activated protein C (APC) is a key component of a natural anticoagulant system that regulates blood coagulation. In vivo, the catalytic activity of APC is regulated by two serpins, alpha1-antitrypsin and the protein C inhibitor (PCI), the inhibition by the latter being stimulated by heparin. We have identified a heparin-binding site in the serine protease domain of APC and characterized the
Anti-inflammatory properties of titanium in the joint environment. An experimental study in rats
Little is known about the tissue reactions to various implant materials which coincide with an inflammatory reaction. We used the avridine arthritis rat model to evaluate the tissue response in the synovial, interstitial and subcutaneous tissues after implant insertion. Quantitative immunohistochemistry showed that normal joint synovial tissue is dominated by ED2-positive resident macrophages. Pol
Development of improved PLIF CH detection using an Alexandrite laser for single-shot investigation of turbulent and lean flames
We report on the development of planar laser-induced fluorescence (PLIF) for CH imaging with improved detection sensitivity for single-shot investigations of turbulent, lean, premixed flames. A ringcavity, pulsed Alexandrite laser was frequency-doubled to excite the lines in the R-branch band-head of the B-X (0,0) band and broadband fluorescence from the B-X (0,1), A-X (1,1) and (0,0) bands, overl