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Structure–activity relationships of galabioside derivatives as inhibitors of E. coli and S. suis adhesins: nanomolar inhibitors of S. suis adhesins

Four collections of Gal1-4Gal derivatives were synthesised and evaluated as inhibitors of the PapG class II adhesin of uropathogenic Escherichia coli and of the PN and PO adhesins of Streptococcus suis strains. Galabiosides carrying aromatic structures at C1, methoxyphenyl O-galabiosides in particular, were identified as potent inhibitors of the PapG adhesin. Phenylurea derivatisation at C3 and me

Long coherence lifetime and electromagnetically induced transparency in a highly-spin-concentrated solid

We have studied a rare-earth-doped crystal, Pr3+:La-2(WO4)(3), which exhibits a high magnetic-moment density. Although the latter favors rare-earth dephasing, a nuclear-spin coherence lifetime of 250 mu s has been observed, as well as electromagnetically induced transparency (EIT). This suggests that a broad range of materials could be considered for quantum information applications such as quantu

Ammoxidation of Propane over Antimony-Vanadium-Oxide Catalysts

Catalysts belonging to the Sb-V-O system were prepared with various Sb/V ratios and were used for propane ammoxidation to acrylonitrile. XRD patterns of freshly prepared samples show those with excess vanadia to consist of V2O5 and SbVO4, while SbVO4 and α-Sb2O4 are constituents in the samples with a Sb/V ratio above unity. High rate and selectivity for propylene formation at low conversion are ch

Triptan-induced contractile (5-HT1B receptor) responses in human cerebral and coronary arteries: relationship to clinical effect

Triptans are agonists at 5-HT1B and 5-HT1D (where 5-HT is 5-hydroxytryptamine; serotonin) receptors and cause vasoconstriction of isolated blood vessels. The aim of the present study was to determine vasoconstrictor potency (EC50) of triptans in human coronary and cerebral arteries and to examine whether there was any relationship with the maximal plasma concentrations (Cmax; nM) of the drugs achi

Linking tree rings, summer aridity, and regional fire data: an example from the boreal forests of the Komi Republic, East European Russia

To evaluate the potential use of tree-ring data as a proxy for fire activity at the scale of a large boreal region, we analyzed a set of regional tree-ring chronologies of Siberian larch (Larix sibirica L.), a spatially implicit annual fire record, and monthly climate data for the Komi Republic for the period 1950-1990. In most years, annually burned area was below 0.001% of the republic's foreste

Chiral bands, dynamical spontaneous symmetry breaking, and the selection rule for electromagnetic transitions in the chiral geometry

A model for a special configuration in triaxial odd-odd nuclei is constructed which exhibits degenerate chiral bands with a sizable rotation, a manifestation of dynamical spontaneous symmetry breaking. A quantum number obtained from the invariance of the model Hamiltonian, which characterizes observable states, is given and selection rules for electromagnetic transition probabilities in chiral ban

An evaluation of horizontal echo sounding as a method for behavioural studies of 0+fish in field experiments

A 120 kHz echo sounder, with two split-beam transducers, was used horizontally to monitor the behaviour of 0+ roach Rutilus rutilis, from June to August, in field enclosures. 0+ roach outside the vegetated area of the enclosures were registered both as schools and as single swimming fish. Combining echo counting and tracking with direct observation of echograms, an estimate of relative abundance o

Scattering of transient electromagnetic waves in reciprocal bi-isotropic media

In this paper propagation of transient electromagnetic waves in a reciprocal bi-isotropic medium is presented. The constitutive relations are convolution integrals with two susceptibility kernels that model the medium. The propagation problem is solved by the introduction of a wave-splitting technique. This wave-splitting is used to solve the propagation problem using either an imbedding approach

Non-lethal predator effects on the performance of a native and an exotic crayfish species

1. I tested the hypothesis that the potential for non-lethal effects of predators are more important for overall performance of the fast-growing exotic signal crayfish (Pacifastacus leniusculus Dana) than for the slower growing native noble crayfish (Astacus astacus L.). I further tested if omnivorous crayfish switched to feed on less risky food sources in the presence of predators, a behaviour th

Laboratory wavelengths for cosmological constraints on varying fundamental constants

Cosmological investigations, using high-redshift quasi-stellar object (QSO) absorption spectra, of possible variations of the fine-structure constant (alpha) require very accurate laboratory wavelengths for a number of resonance transitions from several different species. A change in alpha could be detected as a shift in the wavelengths of atomic transitions in the QSO systems and to accurately de

Voluntary wheel running modulates glutamate receptor subunit gene expression and stress hormone release in Lewis rats

Lewis rats that are known to be addiction-prone, develop compulsive running if they have access to running wheels. The present experiments were aimed 1) to evaluate the activation of stress systems following chronic and acute voluntary wheel running in Lewis rats by measurement of hormone release and gene expression of neuropeptides related to hypothalamic-pituitary-adrenocortical (HPA) axis activ

Automatic Kinematic Calibration of a Modular Gantry-Tau Parallel Robot from a Kinematics Point of View

A method for computer assisted kinematic calibration of a modular Gantry-Tau parallel robot is presented and tested in an experiment. A computer tool developed executes the first step of a kinematic calibration, the choice of appropriate measurement points, using a priori knowledge about kinematic parameters, e.g. obtained with a measuring tape. This step is performed by intersecting the robot's k

Genetic Regulation of Bone Traits Is Influenced by Sex and Reciprocal Cross in F-2 Progeny From GK and F344 Rats

A genome-wide linkage analysis to identify quantitative trait loci (QTLs) for bone phenotypes was performed in an F-2 intercross of inbred spontaneously type 2 diabetic GK and normoglycemic F344 rats (108 males and 98 females). The aim of the study was to locate genome regions with candidate genes affecting trabecular and cortical bone and to investigate the effects of sex and reciprocal cross. pQ

Whole-lake carbon-13 additions reveal terrestrial support of aquatic food webs

Ecosystems are supported by organic carbon from two distinct sources. Endogenous carbon is produced by photosynthesis within an ecosystem by autotrophic organisms. Exogenous carbon is produced elsewhere and transported into ecosystems. Consumers may use exogenous carbon with consequent influences on population dynamics, predator-prey relationships and ecosystem processes(1). For example, exogenous

Are there differences of inflammatory bio-markers between diabetic and non-diabetic patients with critical limb ischemia?

Aim. This observational study was undertaken in order to analyse whether any differences could be detected between diabetic and non-diabetic patients with critical limb ischemia (CLI) concerning the inflammatory response. Methods. A total number of 259 consecutive patients with CLI were treated between October 2001 and January 2003. Results. Among the 259 patients, 135 (52%) had diabetes, previous

Pollen competition reduces inbreeding depression in Collinsia heterophylla (Plantaginaceae)

We tested two predictions of the hypothesis that competition between self-pollen may mitigate negative genetic effects of inbreeding in plants: (1) intense competition among self-pollen increases offspring fitness; and (2) pollen competition reduces the measured strength of inbreeding depression. We used Collinsia heterophylla (Plantaginaceae), an annual with a mixed mating system, to perform cont

No transplacental passage of standard heparin or an enzymatically depolymerized low molecular weight heparin

In 21 women who had an abortion by hysterotomy between the 15th and 23rd week of pregnancy, the possibility that unfragmented heparin or low molecular weight heparin (LMWH) passed the placental barrier to the foetus was studied. Laboratory analyses included amidolytic assays of factor Xa inhibitory activity (XaI), antithrombin III (ATIII) and a direct measurement of heparin-like substances in plas