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Distribution and diel migration of macroinvertebrates within dense submerged vegetation

1. We studied vertical and horizontal distribution of macroinvertebrates within a dense stand of Chara spp. in Lake Krankesjon, southern Sweden. Invertebrates were sampled at three depths within the vegetation and at three distances from the vegetation edge during day and night in July and August. Corresponding samples of oxygen content of the water were taken. 2. The densities (number of inverteb

Nerve regeneration in a 'pseudo-nerve' graft created in a silicone tube

The pseudo-nerve, which contains longitudinal Schwann cell columns without axons and surrounded by perineurium-like tissue but no axons (Q. Zhao, L.B. Dahlin, M. Kanje, G. Lundborg, Brain Res. 592 (1992) 106-114), was applied as a graft to repair nerve defect in rats. Creation of the pseudo-nerve was accomplished by inserting the proximal and distal stumps of a cut sciatic nerve into a silicone tu

Gas6 promotes inflammation by enhancing interactions between endothelial cells, platelets, and leukocytes

The role of Gas6 in enclothelial cell (EC) function remains incompletely characterized. Here we report that Gas6 amplifies EC activation in response to inflammatory stimuli in vitro. In vivo, Gas6 promotes and accelerates the sequestration of circulating platelets and leukocytes on activated endothelium as well as the formation and enclothelial sequestration of circulating platelet-leukocyte conju

Perilipin A is essential for the translocation of hormone-sensitive lipase during lipolytic activation

A key step in lipolytic activation of adipocytes is the translocation of hormone-sensitive lipase (HSL) from the cytosol to the surface of the lipid storage droplet. Adipocytes from perilipin-null animals have an elevated basal rate of lipolysis compared with adipocytes from Wild-type mice, but fail to respond maximally to lipolytic stimuli. This defect is downstream of the p-adrenergic receptor-a

Analysis of heterocyclic amines in food products: interlaboratory studies

A feasibility study and two interlaboratory exercises on the determination of selected heterocyclic amines (HAs) in beef extract, organised in the framework of a European project, are presented. The aim of these exercises was to improve the quality of the laboratories and to evaluate the performance of a standardised analytical method and also the methods currently used by each of the participants

Diversity, distribution and exchange of blood parasites meeting at an avian moving contact zone

Research on contact zones has paid relatively little attention to host-parasite interactions, although these situations have important but different implications depending on whether one considers the host or the parasite's perspective. We investigated both the role of a host contact zone in parasite expansion and whether parasites could influence contact zone dynamics. We studied the diversity an

Association of tapasin and COPI provides a mechanism for the retrograde transport of major histocompatibility complex (MHC) class I molecules from the Golgi complex to the endoplasmic reticulum

Tapasin is a subunit of the transporter associated with antigen processing (TAP). It associates with the major histocompatibility complex (MHC) class I. We show that tapasin interacts with beta- and gamma-subunits of COPI coatomer. COPI retrieves membrane proteins from the Golgi network back to the endoplasmic reticulum (ER). The COPI subunit-associated tapasin also interacts with MHC class I mole

Impacts of aerosol chemical composition on microphysics and precipitation in deep convection

Aerosols affect precipitation by modifying cloud properties such as cloud droplet number concentration (CDNQ. Aerosol effects on CDNC depend on aerosol properties such as number concentration, size spectrum, and chemical composition. This study focuses on the effects of aerosol chemical composition on CDNC and, thereby, precipitation in a mesoscale cloud ensemble (MCE) driven by deep convective cl

Cytogenetic and molecular genetic evolution of chronic myeloid leukemia.

Chronic myeloid leukemia (CML) is genetically characterized by the presence of the reciprocal translocation t(9;22)(q34;q11), resulting in a BCR/ABL gene fusion on the derivative chromosome 22 called the Philadelphia (Ph) chromosome. In 2-10% of the cases, this chimeric gene is generated by variant rearrangements, involving 9q34, 22q11, and one or several other genomic regions. All chromosomes hav

Carbon nanorings: A challenge to theoretical chemistry

High-level quantum-chemical methods show that the binding in the inclusion complex of hexamethylbenzene (HMB) in 6-cycloparaphenitacetylene (6-CPPA) cannot be explained only in terms of electrostatic interactions-caused by the polarization associated to curved a-conjugated systems-and the inclusion of dispersion forces is definitely needed. The theoretical description of van der Wools interactions

Linkage mapping reveals sex-dimorphic map distances in a passerine bird

Linkage maps are lacking for many highly influential model organisms in evolutionary research, including all passerine birds. Consequently, their full potential as research models is severely hampered. Here, we provide a partial linkage map and give novel estimates of sex-specific recombination rates in a passerine bird, the great reed warbler (Acrocephalus arundinaceus). Linkage analysis of genot

Comparison of different extraction techniques for isolation of antioxidants from sweet grass (Hierochloe odorata)

Strong antioxidants, 5,8-dihydroxycoumarin and 5-hydroxy-8-O-beta-D-glucopyranosyl-benzopyranone were extracted from sweet grass (Hierochloe odorata L.) by using Soxhlet (SE), microwave-assisted (MAE) and supercritical fluid carbon dioxide (SFE) extractions at different extraction schemes and parameters. One-step MAE gave the most concentrated extract with 8.15% of 5,8-dihydroxycoumarin (extract y

Introduction of human papillomavirus (HPV) vaccination in Sweden

The Swedish National Board of Health and Welfare (NBH) decided that a vaccine that protects against cervical cancer caused by human papillomavirus (HPV) should be included in the childhood vaccination directive as a nationwide-programme targeting 12-yearold girls from 2010 as a part of the school-health programme. Currently, vaccination of girls 13-18 years of age is covered by the public insuranc

An amperometric biosensor based on laccase immobilized in polymer matrices for determining phenolic compounds

An amperometric enzyme electrode based on laccase for determining phenolic compounds is proposed. The following three types of polymer materials were used for enzyme immobilization on the surface of a glassy-carbon electrode: positively charged cetyl ethyl poly (ethyleneimine) (CEPEI) and negatively charged commercial Nafion and Eastman AQ 29D polymers. The advantages and disadvantages of each of

Identification of polyenic hydrocarbons from the northern winter moth, Operophtera fagata, and development of a species specific lure for pheromone traps

In order to elucidate the composition of the female sex pheromone of the northern (beech) winter moth, Operophtera fagata Scharf. (Lepidoptera: Geometridae), ovipositor extracts of unmated, calling females were analysed by gas chromatography with simultaneous electroantennographic and flame ionization detection (GC-EAD/FID). Male antennal responses indicated three active components, two of which h

Effect of poly(ethylene glycol) on enzymatic hydrolysis and adsorption of cellulase enzymes to pretreated lignocellulose

There is a need to develop the enzymatic hydrolysis of cellulose for production of ethanol from biomass. In recent years the inhibitory effects of lignin in lignocellulosic substrates has been the focus of several studies. This points to the importance of understanding the interactions between cellulose degrading enzymes and lignin. Surface active substances have been shown to adsorb to lignin sur

Overactive bladder--pharmacological aspects.

The micturition reflex can be initiated by contraction or distension of detrusor smooth muscle cells, or by signals from the urothelium. It has been shown that bladder distension causes release of ATP from the urothelium and that ATP can activate P2X(3) receptors on suburothelial afferent nerve terminals to evoke a neural discharge. However, most probably the activation of afferent fibres during b

ARAGORN, a program to detect tRNA genes and tmRNA genes in nucleotide sequences

A computer program, ARAGORN, identifies tRNA and tmRNA genes. The program employs heuristic algorithms to predict tRNA secondary structure, based on homology with recognized tRNA consensus sequences and ability to form a base-paired cloverleaf. tmRNA genes are identified using a modified version of the BRUCE program. ARAGORN achieves a detection sensitivity of 99% from a set of 1290 eubacterial, e