30 research outputs found
Molecular characterisation, evolution and expression analysis of g-type lysozymes in Ciona intestinalis
Lysozyme is an important defense molecule of the innate immune system. Known for its bactericidal
properties, lysozyme catalyzes the hydrolysis of b-(1,4)-glycosidic bonds between the N-acetyl glucosamine
and N-acetyl muramic acid in the peptidoglycan layer of bacterial cell walls. In this study, the
complete coding sequence of four g-type lysozymes were identified in Ciona intestinalis. Phylogenetic
analysis and modelling supported the hypothesis of a close relationship with the vertebrate g-type lysozymes
suggesting that the C. intestinalis g-type lysozyme genes (CiLys-g1, Cilys-g2, CiLys-g3, CiLys-g4)
share a common ancestor in the chordate lineage. Protein motif searches indicated that C. intestinalis gtype
lysozymes contain a GEWL domain with a GXXQ signature, typical of goose lysozymes. Quantitative
Real-Time PCR analysis results showed that transcripts are expressed in various tissues from
C. intestinalis. In order to determine the involvement of C. intestinalis g-type lysozymes in immunity, their
expression was analyzed in the pharynx, showing that transcripts were significantly up-regulated in
response to a challenge with lipopolysaccharide (LPS). These data support the view that CiLys g-type are
molecules with potential for immune defense system against bacterial infection
Псевдодифференциальные уравнения на многообразиях со сложными особенностями на границе
Рассматриваются модельные псевдодифференциальные уравнения в канонических многомерных областях. Особенности могут представлять собой объединения конусов или вырождаться в конусы меньшей размерности. Концепция волновой факторизации, использованная автором ранее, позволяет и в этих ситуациях описать картину разрешимости вышеупомянутых уравнени
The Computability-Theoretic Content of Emergence
In dealing with emergent phenomena, a common task is to identify useful descriptions of them in terms of the underlying atomic processes, and to extract enough computational content from these descriptions to enable predictions to be made. Generally, the underlying atomic processes are quite well understood, and (with important exceptions) captured by mathematics from which it is relatively easy to extract algorithmic con- tent. A widespread view is that the difficulty in describing transitions from algorithmic activity to the emergence associated with chaotic situations is a simple case of complexity outstripping computational resources and human ingenuity. Or, on the other hand, that phenomena transcending the standard Turing model of computation, if they exist, must necessarily lie outside the domain of classical computability theory. In this article we suggest that much of the current confusion arises from conceptual gaps and the lack of a suitably fundamental model within which to situate emergence. We examine the potential for placing emer- gent relations in a familiar context based on Turing's 1939 model for interactive computation over structures described in terms of reals. The explanatory power of this model is explored, formalising informal descrip- tions in terms of mathematical definability and invariance, and relating a range of basic scientific puzzles to results and intractable problems in computability theory
SINGULAR INTEGRAL EQUATIONS WITH MULTIPLICATIVE CAUCHY-TYPE KERNELS
Abstract. In this paper we consider singular integral equations of the first kind with multiplicative Cauchy–type kernels defined on n–dimensional domains. We give their general solutions in the class of Hölder continuous functions and propose the statements of uniqueness problem. Key words: singular integral equation, Cauchy kernel, multiplicative kernel. AMS Mathematics Subject Classification: 45E05
Ultrasmall superparamagnetic particles of iron oxide allow for the detection of metastases in normal sized pelvic lymph nodes of patients with bladder and/or prostate cancer
Aim: Lymph node metastases influence prognosis and outcome in patients with bladder and prostate cancer. Cross sectional imaging criteria are limited in detecting metastases in normal sized lymph nodes. This prospective study assessed the diagnostic accuracy of ultrasmall superparamagnetic particles of iron oxide (USPIO)-enhanced magnetic resonance imaging (MRI) for the detection of metastases in normal sized lymph nodes using extended pelvic lymph node dissection (ePLND) and histopathology as the reference standard. Methods: Seventy-five patients (bladder cancer, n = 19, prostate cancer n = 48, both, n = 8) were examined using 3T MR before and after USPIO-administration. A preoperative reading with two readers in consensus and a second postoperative reading with three independent blinded readers were performed. Results were correlated with histopathology and diagnostic accuracies were calculated for all readings. Results: A total of 2993 lymph nodes were examined histopathologically. Fifty-four metastatic nodes were found in 20/75 patients (26.7%). The first reading had a sensitivity of 55.0%, specificity of 85.5%, positive predictive value (PPV) of 57.9%, negative predictive value (NPV) of 83.9%, and diagnostic accuracy (DA) of 77.3% on a per patient level. The second reading had a mean sensitivity of 58.3%, specificity of 83.0%, PPV of 58.0%, NPV of 84.4% and DA of 76.4% on a per patient level. The majority of missed metastases were smaller than 5 mm in short axis diameter. Conclusions: USPIO-enhanced MRI in bladder and prostate cancer patients allows detection of metastases in normal sized lymph nodes and might guide the surgeon to remove suspicious lymph nodes not included in standard PLND
Geometry of D_4 conformal triality and singularities of tangent surfaces
It is well known that the projective duality can be understood in the context of geometry of An-type. In this paper, as D4-geometry, we construct explicitly a flag manifold, its triplefibration and differential systems which have D4-symmetry and conformal triality. Then we give the generic classification for singularities of the tangent surfaces to associated integral curves, which exhibits the triality. The classification is performed in terms of the classical theory on root systems combined with the singularity theory of mappings. The relations of D4-geometry with G2-geometry and B3-geometry are mentioned. The motivation of the tangent surface construction in D4-geometry is provided
A biconjugate gradient type algorithm on massively parallel architectures
The biconjugate gradient (BCG) method is the natural generalization of the classical conjugate gradient algorithm for Hermitian positive definite matrices to general non-Hermitian linear systems. Unfortunately, the original BCG algorithm is susceptible to possible breakdowns and numerical instabilities. Recently, Freund and Nachtigal have proposed a novel BCG type approach, the quasi-minimal residual method (QMR), which overcomes the problems of BCG. Here, an implementation is presented of QMR based on an s-step version of the nonsymmetric look-ahead Lanczos algorithm. The main feature of the s-step Lanczos algorithm is that, in general, all inner products, except for one, can be computed in parallel at the end of each block; this is unlike the other standard Lanczos process where inner products are generated sequentially. The resulting implementation of QMR is particularly attractive on massively parallel SIMD architectures, such as the Connection Machine
Inverse Scattering Problem on the Axis for the Schrödinger Operator with Triangular 2 x 2 Matrix Potential. I. Main Theorem
The necessary and sufficient conditions for solvability of ISP under consideration are obtained