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Structural aspects of signal transduction in B-cells

Signal transduction in hematopoietic cells is a highly specific process. The stimulation of B cell receptor following antigen binding triggers, as a first step, phosphorylation of the cytoplasmic immunoreceptor tyrosine-based activation motifs (ITAMs). Src family tyrosine kinases Blk, Fyn, Lck, and Lyn as well as spleen kinase, Syk, are activated to transmit the signal further. In this review the

A repetitive sequence of Epstein-Barr virus nuclear antigen 6 comprises overlapping T cell epitopes which induce HLA-DR-restricted CD4(+) T lymphocytes

Most human adults carry the Epstein-Barr virus (EBV) and develop immunological memory against the structural and the virus-encoded cellular proteins. The EBV nuclear antigen 6 (EBNA6) elicits cytotoxic T cell responses and it also maintains a persistent antibody response. The majority of sera from EBV-seropositive individuals reacts with a synthetic peptide, p63, comprising 21 amino acids of a rep

Network analysis of the state space of discrete dynamical systems

We study networks representing the dynamics of elementary 1D cellular automata (CA) on finite lattices. We analyze scaling behaviors of both local and global network properties as a function of system size. The scaling of the largest node in-degree is obtained analytically for a variety of CA including rules 22, 54, and 110. We further define the path diversity as a global network measure. The coa

Rayleigh mixture model-based hidden Markov modeling and estimation of noise in noisy speech signals

In this paper, we propose a new statistical model for noise periodogram modeling and estimation. The proposed model is a hidden Markov model (HMM) with a Rayleigh mixture model (RMM) in each state. For this new model, we derive an expectation-maxinuzation (EM) training algorithm and a minimum meansquare error (NIMSE) noise periodogram estimator. It is shown that when compared to the Gaussian mixtu

Statistical methods for monitoring the relationship between the IFCC reference measurement procedure for hemoglobin A(1c) and the designated comparison methods in the United States, Japan, and Sweden

BACKGROUND: The American Diabetes Association (ADA)/European Association for the Study of Diabetes (EASD)/International Diabetes Federation GDFAFCC Consensus Statement on the worldwide standardization of HbA(1c) states that"...[HbA(1c)] results are to be reported world-wide in IFCC units...and derived NGSP units...,using the IFCC-NGSP master equation." METHODS: We describe statistical methods to e

Compass orientation and possible migration routes of passerine birds at high arctic latitudes

The use of celestial or geomagnetic orientation cues can lead migratory birds along different migration routes during the migratory journeys, e.g. great circle routes (approximate), geographic or magnetic loxodromes. Orientation cage experiments have indicated that migrating birds are capable of detecting magnetic compass information at high northern latitudes even at very steep angles of inclinat

Intraspecific competition in tadpoles of Rana arvalis: does it matter in nature? A field experiment

Tadpole growth and development are easily affected by intraspecific competition in tank experiments, provided treatment density is sufficiently high. Is this a phenomenon also observed in nature? A pond was divided into four tadpole-proof sections. Each year for 8 years, all spawn laid by moorfrogs (Rana arvalis) in this pond was relocated to create relative spawn and tadpole densities of 1:4:1:4.

Laboratory and field test of a sampling method for characterization of combustion aerosols at high temperatures

The objective of this study was to design and experimentally examine a sampling method for high-temperature aerosols from biomass combustion, in which nucleation and condensation from fly ash forming vapors is controlled. The sampling method includes a high-temperature probe in which the hot gas is diluted and then cooled. Laboratory results from sampling a model aerosol with known concentrations

Fluorescence diffuse optical tomography using upconverting nanoparticles

Fluorescence diffuse optical tomography (FDOT) can provide important information in biomedical studies. In this ill-posed problem, suppression of background tissue autofluorescence is of utmost importance. We report a method for autofluorescence-insensitive FDOT using nonlinear upconverting nanoparticles (NaYF4:Yb3+/Tm3+) in a tissue phantom under excitation intensities well below tissue-damage th

Effect of ileal infusion of short-chain fatty acids on pancreatic prandial secretion and gastrointestinal hormones in pigs

Objectives: Nutrients passing the ileum induce mechanisms regulating pancreatic secretion, but the effect of short-chain fatty acids (SCFAs) present in the ileum because of either intestinal fermentation or due to the cecoileal reflux is still unclear. This study investigated the effect of ileal SCFAs on pancreatic secretion and plasma levels of peptide YY, cholecystokinin, motilin, and neurotensi

Amino acid residues His183 and Glu264 in Bacillus subtilis ferrochelatase direct and facilitate the insertion of metal ion into protoporphyrin IX

Ferrochelatase catalyzes the terminal step in the heme biosynthetic pathway, i.e., the incorporation of Fe(II) into protoporphyrin IX. Various biochemical and biophysical methods have been used to probe the enzyme for metal binding residues and the location of the active site. However, the location of the metal binding site and the path of the metal into the porphyrin are still disputed. Using sit

Design of PID controllers based on constrained optimisation

This paper presents a new design method for PID controllersbased on optimization of load disturbance rejection with constraintson robustness to model uncertainties. The design also deliversparameters to deal with measurement noise and set point response. Thus, theformulation of the design problem captures four essential aspects ofindustrial control problems, leading to a constrained optimizationpr

Neuroprotective effects of the beta-carboline abecarnil studied in cultured cortical neurons and organotypic retinal cultures.

Presently there is no neuroprotective pharmacological treatment of proven clinical safety and efficacy available. The purpose of this study was to investigate whether the ss-carboline, abecarnil (Abe), which has already passed clinical phase III trials in patients with anxiety disorders, is neuroprotective in in vitro models of cerebral ischemia or excitotoxicity. Abe (100 nM) protected cultured c

Systematic truncation of the virtual space in multiconfigurational perturbation theory

A method is suggested which allows truncation of the virtual space in Cholesky decomposition-based multiconfigurational perturbation theory (CD-CASPT2) calculations with systematic improvability of the results. The method is based on a modified version of the frozen natural orbital (FNO) approach used in coupled cluster theory. The idea is to exploit the near-linear dependence among the eigenvecto

How to trap a slug: Commercial versus homemade slug traps

The Iberian Slug, Arion lusitanicus Mabille (Stylomatophora: Arionidae), has developed into a destructive pest in Swedish gardens and orchards over the past 10-20 years. Many attempts to eradicate this pest have been made using a variety of different methods. The aim of this study was to investigate the effectiveness of two different types of homemade traps made from simple, inexpensive materials

An immunochemical method for quantitative determination of latent antithrombin, the reactive center loop-inserted uncleaved form of antithrombin.

Antithrombin (AT) is a serine protease inhibitor that has thrombin, factors IXa and Xa as target proteases. In addition to active native AT, two other forms have been identified in plasma: the reactive center loop inserted cleaved and latent, uncleaved forms. Both have been shown to be present in normal human blood. Latent AT forms a dimer with native AT in vitro, thus inactivating the native form

Contrast Biases The Autocorrelation Phase Shift Estimation In Doppler Tissue Imaging

Quantitative assessment of regional myocardial function at rest and during stress with Doppler tissue imaging (DTI) plays an important role in daily routine echocardiography. However, reliable visual analysis is largely dependent on image quality and adequate border delineation, which still remains a challenge in a significant number of patients. In this respect, an ultrasound contrast agent (UCA)