Search results for "fragmentation"
showing 8 items of 798 documents
Fibre fragment distribution in a single-fibre composite tension test
2001
Abstract Single fibre fragmentation tests are performed for brittle fibres with Weibull strength distribution and different surface treatments. The fragmentation process is modelled and closed-form expressions for break spacing distribution are obtained. The model accounts for the effect of finite fibre length on the initial fragmentation as well as for break interaction on the advanced fragmentation stage. It is assumed that the exclusion zone due to fibre–matrix interface failure and stress recovery in the fibre is linearly dependent on the applied load. This assumption is validated experimentally. The derived theoretical average fragment length dependence on applied load is used to deter…
An experimental approach to oxidative stress effect on sperm motility and DNA fragmentation
2018
En el estudio de la fertilidad masculina en todas las especies animales, la movilidad espermática, junto a la concentración y morfometría son los parámetros principales y más básicos en la evaluación de la calidad de los espermatozoides. La infertilidad masculina habitualmente se asocia con tasas anormales de estos parámetros seminales. Aún teniendo, los espermatozoides tasas adecuadas de todos estos parámetros no se puede garantizar la capacidad de fertilizar y/o desarrollar un cigoto. Por lo tanto, está claro que el examen rutinario del semen y los espermatozoides en la eyaculación no puede evaluar otros parámetros importantes en el proceso de fecundación como es capacitación espermática …
A Proposal of Process Fragment Definition and Documentation
2012
This paper focuses on the field of Situational Method Engineering (SME) for the construction of agent-oriented design processes. Whatever SME approach a method designer wants to use, he has to manage two main elements: the (method or process) fragment and the repository where it is stored. Specific fragment definition and documentation are fundamental during these activities, for new process composition, and for the consequent system design activities. This paper aims at illustrating a proposal of fragment definition and documentation. This proposal is aimed to be an input for the IEEE FIPA Design Process Documentation and Fragmentation working group and, as regards our own research work, t…
The effect of defect location on coating fragmentation patterns under biaxial tension
2005
Fragmentation of a coating possessing orthogonal preferential crack propagation directions is modeled for equibiaxial tensile loading. Two plausible cracking scenarios are compared, caused by flaws randomly distributed over the area of the coating or along the coating fragment edges. The two fragmentation scenarios considered are shown to yield qualitatively different fragment patterns.
Studies in organic mass spectrometry. Part 23. Role of the aroyl group on the competitive fragmentation reactions of the molecular ion of aroylanilid…
1999
The 70 eV and mass-analysed ion kinetic energy (MIKE) spectra of some thiophenecarboxanilides and benzoylanilides (1–10) have been compared in order to investigate the role of the aroyl (or heteroaroyl) moiety on the abundance of the competitive fragmentation reactions occurring in their molecular ions (amide–bond cleavage and phenol radical ion formation). It has been shown that the electron ionisation induced decompositions with high (70 eV) and low (MIKE) internal energy excess are qualitatively similar, but remarkable quantitative differences have been observed that can be accounted for in terms of the different effectiveness in the transmission of electronic effects of substituents in …
Posting and agency work in British construction and hospitality: the role of regulation in differentiating the experiences of migrants
2017
This article engages with IHRM debates on the transnational regulation of labour, exploring how migration policy and work fragmentation affect employment dynamics in multi-employer settings. It dra...
Apoptosis in human unfertilized oocytes after intracytoplasmic sperm injection
2005
Objective To investigate the presence of programmed cell death in unfertilized oocytes after intracytoplasmic sperm injection (ICSI), assuming that previous apoptotic events could be correlated with the fertilization failure. Design Comparison of the rate of DNA fragmentation in human oocytes at different stages of maturation soon after pick-up (control) and in unfertilized oocytes after ICSI treatment. Setting In vitro fertilization (IVF) laboratory with extensive ICSI experience. Patient(s) Sixty-three patients undergoing assisted fertilization by ICSI. Intervention(s) Terminal deoxynucleotidyl transferase-mediated digoxigenin-dUTP nick-end labeling (TUNEL) assay and anticaspase-3 cleaved…
Profiling Dopamine-Induced Oxidized Proteoforms of β-synuclein by Top-Down Mass Spectrometry
2021
The formation of multiple proteoforms by post-translational modifications (PTMs) enables a single protein to acquire distinct functional roles in its biological context. Oxidation of methionine residues (Met) is a common PTM, involved in physiological (e.g., signaling) and pathological (e.g., oxidative stress) states. This PTM typically maps at multiple protein sites, generating a heterogeneous population of proteoforms with specific biophysical and biochemical properties. The identification and quantitation of the variety of oxidized proteoforms originated under a given condition is required to assess the exact molecular nature of the species responsible for the process under investigation…