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We have recently introduced a composite smeared finite element (CSFE) to model gradient-driven mass transport in biological tissue. The transport from capillary system is smeared in a way to transform 1D transport to a continuum, while the tissue is considered as a continuum. Coupling between the smeared pressure and concentration field is achieved through 1D connectivity elements assigned at each FE node. Here we extend our smeared model to include the lymphatic system. The lymphatic vessels are treated in a way analogous to the capillaries, by introducing the corresponding Darcy and diffusion tensors. Additional connectivity elements are added. In the numerical examples we demonstrate accuracy of the smeared model and the effects of the lymph on the pressure and concentration within the extracellular space, assuming that there is no transport to the cell space. [ABSTRACT FROM AUTHOR]

In this paper, we introduce an incremental formulation for large strains which is based on the nodal forces increments. It uses the linear strain increments at the current configuration as the fundamental strain measure, and consequently the stress increments which produce the nodal force increments. It does not assume any total strain and stress calculation according to total values of (large) displacements. It rather employs summation of internal finite element nodal forces during the incremental-iterative computational procedures. Solutions according to this new formulation are compared with a standard updated Lagrangian formulation, with the Green- Lagrangian strains evaluated using the total displacement derivatives with respect to the current reference configurations. The presented incremental-force based formulation can be considered as a generalization of the use of logarithmic strains. [ABSTRACT FROM AUTHOR]

The aim of this study was to investigate the release performance of an electrospun composite drug loaded nanofiber mat. Electrospun nanofiber mats are promising as drug carriers which offer site-specific delivery of drugs to a target in the human body and may be used for cancer therapy. The authors have formulated a simple radial 1D finite element, which is used to model diffusion within fibers releasing a drug to the surrounding medium discretized by continuum 3D finite elements. The numerical model includes degradation effects and hydrophobicity at the fibers/surroundings interface. For the purpose of experimental investigation, a poly(D,L-lacticco-glycolic acid) (PLGA) implant has been created at the Faculty of Technology and Metallurgy, University of Belgrade. The radial 1D element provides accurate predictions of the diffusion process and serves as an efficient tool for describing transport inside the polymer fiber and surrounding porous medium; which is illustrated through numerical examples. [ABSTRACT FROM AUTHOR]

Summary What is known and Objective: There is almost no published information about reliability of scales for causality assessment in hepatotoxicity at pharmacovigilance centres. The aim of this study was to compare two commonly used scales in cases of unexpected hepatotoxicity, in evaluating their accuracy and reproducibility at pharmacovigilance centres (in signal detection). Methods: Two scales [Council for International Organizations of Medical Sciences or Rousel Uclaf Causality Assessment Method (CIOMS/RUCAM) and NARANJO] were compared in 19 cases of unexpected hepatotoxicity reported during 2004-2009. Data of the cases (with initial clinical assessments) were collected by a network of medical specialists using a structured reporting form. Later, two independent observers assessed each case using both scales. The accuracy and reproducibility of the scales were analysed by Kappa weighted (Kw) test. Results: Both scales (CIOMS/RUCAM vs. NARANJO) showed moderate agreement with the initial clinical assessments (accuracy) for observer A (Kw: 0·56 vs. 0·60) and substantial agreement for observer B (Kw: 0·72 vs. 0·70), with high agreement between observers (Kw: 0·84 vs. 0·67). Both observers (A vs. B) found low agreement between scales (Kw: 0·21 vs. 0·50), with lower scores for the CIOMS/RUCAM scale in 11 and nine cases, respectively. For an early perception of unexpected serious reactions, the scale is more useful if it is not asked for 'previous knowledge' and if it gives higher causality score. What is new and conclusion: The CIOMS/RUCAM scale showed similar accuracy, but better reproducibility (agreement between observers) than the NARANJO scale, and therefore is recommended for use at pharmacovigilance centres. Fine-tuning of the CIOMS/RUCAM method could contribute to better detection of unexpected hepatotoxicity. [ABSTRACT FROM AUTHOR]

Water soluble fullerene (C60) derivative fullerenol C60(OH)24 nano-particles (FNP) are a promising candidate for many biomedical applications due to, besides other properties, strong free-radical scavenging and antioxidative potential. Using the carrageenan-induced rat footpad oedema test, the anti-inflammatory effect of FNP have been estimated in comparison with those of amifostine (AMI) and indomethacin (IND). FNP and IND, dissolved in dimethylsulfoxide, and AMI, dissolved in saline, were intraperitoneally injected to rats in a dose range 12.5 - 75 mg/kg, 3 - 10 mg/kg, and 50 - 300 mg/kg, respectively. The control groups were given corresponding vehicles. The drugs or vehicles were given 30 min before carrageenan injection. Footpad swelling was measured 3 hours after carrageenan application. Calculation of a per cent of inhibition derived through comparison with the control groups was done. Histopathological examination of the inflamed foot skin biopsies was also performed. FNP dose-dependently and significantly reduced the extent of footpad oedema, comparable to that of IND and significantly better than AMI; their ED50 values (in μmol/kg) were: 35.36, 32.12 and 871.0, respectively. Histopathological examination confirmed these results. The largest therapeutic index of FNP suggests their safety for potential use in humans. Our results support the hypothesis that FNP produce a strong acute anti-inflammatory activity [ABSTRACT FROM AUTHOR]

Fish assemblages have been widely used as ecological indicators for assessing the level of environmental degradation and ecosystem health. Environmental disturbances affect the aquatic community structure in terms of abundance and biomass. Therefore, we tested the utility of abundance/biomass comparison (ABC) method, originally developed for marine ecosystems, to detect the anthropogenic disturbance in lotic systems using fish community data. Electrofishing was conducted in the period between 2003 and 2011 at 35 sites along the Southern Morava River basin. The results indicated that species richness strongly influences the utility of ABC method to detect the anthropogenic disturbance in lotic systems. The Warwick (W) statistic showed the positive correlation and the expected direction of response with some factors defining environmental quality, applying it on the samples with greater species richness. This approach has significant power for detecting environmental quality disturbance but may be limited due to effects of habitat variability in riverine environments.

This imaging system aims at recording images of the core size and shape of an imploding deuterium-tritium (DT) microballoon on LMJ inertial confinement fusion (ICF) experiments. Image acquisition is difficult due to the harsh surrounding created by the fusion reaction, which affects system specifications. This one is made of a scintillator, an optical relay, and a CCD camera shielded from the surrounding. The system was tested on different facilities at CEA/DIF, where a spatial resolution of 120 μm was achieved and gamma dose up to 20 rad effects were measured. Setup and performed test are described. [ABSTRACT FROM AUTHOR]

This paper presents the first checklist of the family Chironomidae (Diptera) in Serbia, based on literature citations in two periods (1981/82 and 2010/11) and the unpublished data as well as material examined by the authors. Our survey ranges over the Central, Eastern, Southern and Southeastern parts of Serbia (Southern Morava River basin). We have listed 110 taxa distributed in following five subfamilies: Chironominae (39), Diamesinae (3), Orthocladiinae (48), Prodiamesinae (2) and Tanypodynae (16).

Based on a literature review, the different approaches in the water quality assessment using fish communities in freshwaters are summarized. Fish assemblage indicators, developed throughout the world, were reviewed and the main differences in methodologies, number of metrics and values are summarized. We have drawn attention to the methods used for designing a fish-based index with a particular focus on original developments in North America and its adaptations in many different regions and habitat types. The main obstacles for ecological assessment are scarce ecological information and the problem with the classification. The lack of knowledge is especially true for species assemblages in the relatively unexplored river basins of Europe, e.g. The Balkans peninsular.