Solid-state structure of copper complexes of N-(2-carboxyethyl)chitosan

The sorptivity for ions of the Irving-Williams series (Zn2+, Cu2+, Co2+, Ni2+) was estimated for the chelate sorbent N-(2-carboxyethyl)chitosan cross-linked by nanosecond electron-beam irradiation. The maximum capacity reaches 3.7 mmol/g using a mixture of the appropriate sulfates at pH 4.5. The selectivity of copper sorption is 80%. The structure of the coordination sphere of the copper complexes with N-(2-carboxyethyl)chitosan was investigated by ESR spectroscopy

The 5' → 3' exoribonuclease XRN1/Pacman and its functions in cellular processes and development

XRN1 is a 5' → 3' processive exoribonuclease that degrades mRNAs after they have been decapped. It is highly conserved in all eukaryotes, including homologs in Drosophila melanogaster (Pacman), Caenorhabditis elegans (XRN1), and Saccharomyces cerevisiae (Xrn1p). As well as being a key enzyme in RNA turnover, XRN1 is involved in nonsense-mediated mRNA decay and degradation of mRNAs after they have been targeted by small interfering RNAs or microRNAs. The crystal structure of XRN1 can explain its processivity and also the selectivity of the enzyme for 5' monophosphorylated RNA. In eukaryotic cells, XRN1 is often found in particles known as processing bodies (P bodies) together with other proteins involved in the 5' → 3' degradation pathway, such as DCP2 and the helicase DHH1 (Me31B). Although XRN1 shows little specificity to particular 5' monophosphorylated RNAs in vitro, mutations in XRN1 in vivo have specific phenotypes suggesting that it specifically degrades a subset of RNAs. In Drosophila, mutations in the gene encoding the XRN1 homolog pacman result in defects in wound healing, epithelial closure and stem cell renewal in testes. We propose a model where specific mRNAs are targeted to XRN1 via specific binding of miRNAs and/or RNA-binding proteins to instability elements within the RNA. These guide the RNA to the 5' core degradation apparatus for controlled degradation

Model For The Dynamics Of A Bubble Undergoing Small Shape Oscillations Between Elastic Layers

A model is presented for a pulsating and translating gas bubble in a channel formed by two soft elastic parallel layers. The bubble is free to undergo small shape deformations. Coupled nonlinear second-order differential equations are obtained for the shape and position of the bubble, and numerical integration of an expression for the liquid velocity at the layer interfaces yields an estimate of their displacement. Simulations reveal behavior consistent with laboratory observations.Applied Research Laboratorie

Nonlinear Torsional Wave Beams

An evolution equation with cubic nonlinearity is presented for a torsional wave beam in an isotropic elastic solid. Analytical solutions are presented for the fundamental and third harmonic in the far field of a uniform circular source. Numerical results are presented for harmonic beam patterns at an intermediate distance between the near and far fields, and for a torsional waveform with shocks.Applied Research Laboratorie

Coupled Pulsation And Translation Of A Gas Bubble And Rigid Particle

A nonlinear analytic model describing the interaction of a spherical gas bubble and spherical rigid particle is presented. Both the bubble and particle are free to translate. The model is accurate to fifth order in terms of a nondimensional expansion parameter R/d, where R is a characteristic radius and d is the distance separating the bubble and particle. Numerical simulation results are presented to demonstrate the effects of key particle parameters and an external acoustic source.Applied Research Laboratorie

As características linguísticas e especificações de tradução da geração de novidade “p” de Victor Pelevin

The authors focus on the linguistic features characterising a postmodern novel on the example of the literary work Generation “P” by Victor Pelevin. Firstly, the impossibility of new style invention and the idea of the necessity of different styles combination are highlighted: stylistically marked words such as jargon words, low-colloquial lexis, poetic and archaic words, idioms, and even scientific terms all together create a unique style of the novel. Secondly, the implementation levels of the language game are considered. Two levels of language game representation are analysed: the mix of styles and the loss of figurativeness by phraseological units. The intertextual context of the novel and a common method of postmodernism known as “rewriting” are regarded in the article. A phenomenon of language game and intertextuality are analyzed based on the translation of the novel by Andrew Bromfield.Los autores se centran en los rasgos lingüísticos que caracterizan una novela posmoderna sobre el ejemplo de la obra literaria Generación “P” de Victor Pelevin. En primer lugar, se destaca la imposibilidad de la invención de nuevos estilos y la idea de la necesidad de una combinación de diferentes estilos: palabras marcadas estilísticamente como palabras de jerga, léxico poco coloquial, palabras poéticas y arcaicas, modismos e incluso términos científicos, todos juntos crean una singularidad. estilo de la novela. En segundo lugar, se consideran los niveles de implementación del juego del lenguaje. Se analizan dos niveles de representación de juegos de lenguaje: la mezcla de estilos y la pérdida de figuratividad por unidades fraseológicas. En el artículo se examinan el contexto intertextual de la novela y un método común de posmodernismo conocido como "reescritura". Se analiza un fenómeno de juego de lenguaje e intertextualidad a partir de la traducción de la novela de Andrew Bromfield.Os autores concentram-se nas características linguísticas que caracterizam um romance pós-moderno a partir do exemplo da obra literária Geração “P” de Victor Pelevin. Em primeiro lugar, a impossibilidade de invenção de um novo estilo e a ideia da necessidade de combinação de diferentes estilos são destacadas: palavras marcadas estilisticamente, como jargões, léxico coloquial baixo, palavras poéticas e arcaicas, expressões idiomáticas e até termos científicos, todos juntos criam um ambiente único estilo do romance. Em segundo lugar, os níveis de implementação do jogo de linguagem são considerados. Dois níveis de representação de jogos de linguagem são analisados: a mistura de estilos e a perda de figuratividade por unidades fraseológicas. O contexto intertextual do romance e um método comum de pós-modernismo conhecido como “reescrita” são considerados no artigo. Um fenômeno de jogo de linguagem e intertextualidade são analisados a partir da tradução do romance de Andrew Bromfield

The 5′-3′ exoribonuclease Pacman is required for normal male fertility and is dynamically localized in cytoplasmic particles in Drosophila testis cells

The exoribonuclease Xrn1 is widely recognised as a key component in the 5'-3' RNA degradation pathway. This enzyme is highly conserved between yeast and humans and is known to be involved in RNA interference and degradation of microRNAs as well as RNA turnover. In yeast and human tissue culture cells, Xrn1 has been shown to be a component of P-bodies (processing bodies), dynamic cytoplasmic granules where RNA degradation can take place. In this paper we show for the first time that Pacman, the Drosophila homologue of Xrn1, is localized in cytoplasmic particles in Drosophila testis cells. These particles are present in both the mitotically dividing spermatogonia derived from primordial stem cells and in the transcriptionally active spermatocytes. Pacman is co-localized with the decapping activator dDcp1 and the helicase Me31B (a Dhh1 homologue) in these particles, although this co-localization is not completely overlapping, suggesting that there are different compartments within these granules. Particles containing Pacman respond to stress and depletion of 5'-3' decay factors in the same way as yeast P-bodies, and therefore are likely to be sites of mRNA degradation or storage. Pacman is shown to be required for normal Drosophila spermatogenesis, suggesting that control of mRNA stability is crucial in the testis differentiation pathway

Wie kann man ein originales gefalschtes pestizid erkennen

Um sich vor Fälschungen zu schützen, müssen Sie daher wissen, dass Originalpräparate nicht billig können sein. In den meisten Fällen stellen Unternehmen Medikamente nicht in kleinen Verpackungen her und jedes Medikament sollte ein Hologramm haben

The 5'-3' exoribonuclease pacman is required for epithelial sheet sealing in Drosophila and genetically interacts with the phosphatase puckered

Background information. Ribonucleases have been well studied in yeast and bacteria, but their biological significance to developmental processes in multicellular organisms is not well understood. However, there is increasing evidence that specific timed transcript degradation is critical for regulation of many cellular processes, including translational repression, nonsense-mediated decay and RNA interference. The Drosophila gene pacman is highly homologous to the major yeast exoribonuclease XRN1 and is the only known cytoplasmic 5′–3′ exoribonuclease in eukaryotes. To determine the effects of this exoribonuclease in development we have constructed a number of mutations in pacman by P-element excision and characterized the resulting phenotypes. Results. Mutations in pacman resulted in flies with a number of specific phenotypes, such as low viability, dull wings, crooked legs, failure of correct dorsal/thorax closure and defects in wound healing. The epithelial sheet movement involved in dorsal/thorax closure is a conserved morphogenetic process which is similar to that of hind-brain closure in vertebrates and wound healing in humans. As the JNK (c-Jun N-terminal kinase) signalling pathway is known to be involved in dorsal/thorax closure and wound healing, we tested whether pacman affects JNK signalling. Our experiments demonstrate that pacman genetically interacts with puckered, a phosphatase that negatively regulates the JNK signalling pathway. Conclusions. These results reveal that the 5′–3′ exoribonuclease pacman is required for a critical aspect of epithelial sheet sealing in Drosophila. Since these mutations result in specific phenotypes, our data suggest that the exoribonuclease Pacman targets a specific subset of mRNAs involved in this process. One of these targets could be a member of the JNK signalling pathway, although it is possible that a parallel pathway may instead be affected. The exoribonuclease pacman is highly conserved in all eukaryotes, therefore it is likely that it is involved in similar morphological processes, such as wound healing in human cells

Acoustic waves: should they be propagated forward in time, or forward in space?

The evolution of acoustic waves can be evaluated in two ways: either as a temporal, or a spatial propagation. Propagating in space provides the considerable advantage of being able to handle dispersion and propagation across interfaces with remarkable efficiency; but propagating in time is more physical and gives correctly behaved reflections and scattering without effort. Which should be chosen in a given situation, and what compromises might have to be made? Here the natural behaviors of each choice of propagation are compared and contrasted for an ordinary second order wave equation, the time-dependent diffusion wave equation, an elastic rod wave equation, and the Stokes'/ van Wijngaarden's equations, each case illuminating a characteristic feature of the technique. Either choice of propagation axis enables a partitioning the wave equation that gives rise to a directional factorization based on a natural "reference" dispersion relation. The resulting exact coupled bidirectional equations then reduce to a single unidirectional first-order wave equation using a simple "slow evolution" assumption that minimizes effect of subsequent approximations, while allowing a direct term-to-term comparison between exact and approximate theories.Comment: 12 pages, v2 correcte