143 research outputs found

    Transition of free convection flow inside an inclined parallel walled channel: effects of inclination angle and width of the channel

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    Transition of free convection flow in an inclined parallel walled channel has been investigated numerically by employing k–ɛ turbulent model. Particular attention is paid on how the inclination angle and width of the channel affect the transition process of the flow developing in the channel. The upper plate of the channel is heated isothermally and facing downward, while the lower one is kept under the adiabatic condition. The inclination angle of the channel is varied from 0° to 85° with respect to its vertical position while the distance separating the two plates is systematically reduced from 0.45 to 0.06 m. Distributions of velocity, turbulent kinetic energy and local heat flux are presented to examine the critical distance and the results obtained show good agreement with experimental data available in the literature

    Comparison of newtonian and fourier thermal analysis techniques for calculation of latent heat and solid fraction of aluminum alloys

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    The cooling curve analysis (CCA) has been used extensively in the metal casting industry, usually to predict alloy compositio n and microstructure constituents. The use of CCA can be expanded to other areas of solidification if the zero curves can be properly calculated. In this paper the Newtonian and Fourier techniques of zero curve determination are described. These techniques were developed to calculate latent heat and to determine the correlations between solid fraction and temperature/time for Al-7 wt%Si alloy. The importance of the changes in heat capacity and density of solid and liquid phases during solidification on the latent heat calculations was examined. The latent heat calculated by Computer-Aided Cooling Curve Analysis (CA-CCA) method is compared with those reported in the literature. The effect of experimental procedure and type of sampling cup on the latent heat calculations were studied for both techniques

    Adalimumab for endoscopic and histopathological mucosal healing in paediatric patients with moderate to severe Crohn's disease

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    Abstract Introduction: Deep remission, defined as clinical remission with mucosal healing (MH), with anti-tumor necrosis factor (TNF)-α agents is a new target for therapy in Crohn's disease (CD). Provided that the efficacy of infliximab (IFX) for induction of MH in CD has been demonstrated, there are much less data for adalimumab (ADA), and none concerning MH on histopathological examination. Aim: To assess the impact of biological therapy with ADA on both endoscopic and histopathological MH in paediatric patients with CD. Material and methods: Twenty-three children (10 boys and 13 girls) aged 13.0 ±9.3 years with moderate to severely active CD diagnosed at the mean age of 5.5 ±0.83 years were included into the study. Seven (30.4%) patients had been previously treated with infliximab and switched to ADA due to intolerance or loss of response. Colonoscopy and gastroscopy with sample collection were performed in all patients before and after induction treatment with ADA. Clinical activity of the disease was assessed using the Paediatric Crohn's Disease Activity Index (PCDAI), and the endoscopic activity was scored using the Simple Endoscopic Score (SES-CD). Histological changes were evaluated by a self-adapted numerical scoring system. Results: Four (17.4%) patients reached clinical remission (PCDAI ≤ 10). When comparing data at baseline and at a week after ADA treatment, a significant decrease was observed in median PCDAI and in SES-CD score between the initial and control colonoscopies. We reported a decrease in histological scale, which was not statistically significant. A correlation was found between PCDAI and SES-CD score. Conclusions: Biological therapy with ADA has a positive impact on endoscopic mucosal healing in paediatric patients with CD, which is not associated with histological evidence of suppression of inflammation. Endoscopic MH correlates better than microscopic one with clinical remission

    Monoclonal Antibody and Fusion Protein Biosimilars Across Therapeutic Areas: A Systematic Review of Published Evidence

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    Role of homocysteine in the pathology of some neurological diseases

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    Lately the role of homocysteine in pathology of diseases, also neurological, seems to be very interesting. Homocysteine is an amino acid containing thiol group, produced in body by demethylation of methionine. An important role in its metabolism play vitamins from group B (vitamin B6 and B12), folic acid and enzymes: reductase and synthetase. The level of homocysteine depends on genetic and congenital factors. Normal concentration of homocysteine in serum for people under 60 years old is 5-15 μmol/l, for older it is higher. Recently there was found the correlation between the excess of homocysteine and the risk of vascular diseases, dementia. It is also interesting if the level of homocysteine changes in patients with Parkinson’s disease. It can also be teratogenic. It was found that in epileptic patients the level of homocysteine is higher. Antiepileptic drugs which induce cytochrome P450 cause increase in homocysteine levels.Ostatnio obserwuje się duże zainteresowanie homocysteiną i jej rolą w patologii chorób, także neurologicznych. Homocysteina jest siarkowym aminokwasem zawierającym grupę tiolową, powstającym w organizmie w wyniku demetylacji metioniny. W jej metabolizmie ważną rolę odgrywają witaminy z grupy B (witamina B6 i B12), kwas foliowy oraz enzymy z grupy reduktaz i syntetaz. Poziom homocysteiny zależny jest od czynników wrodzonych i nabytych. Prawidłowy poziom homocysteiny w surowicy krwi dla osób poniżej 60. roku życia wynosi 5-15 mmol/l, dla ludzi starszych dopuszcza się wyższy. Stwierdzono zależność między podwyższonym poziomem homocysteiny a ryzykiem chorób naczyniowych czy otępiennych. Zainteresowanie wzbudziło również zachowanie się poziomu homocysteiny u pacjentów z chorobą Parkinsona. Podwyższony poziom homocysteiny może mieć też działanie teratogenne. Niedawno zwrócono uwagę, że u pacjentów leczonych lekami przeciwpadaczkowymi poziom homocysteiny może być podwyższony. Leki przeciwpadaczkowe indukujące cytochrom P450 powodują wzrost stężenia homocysteiny w surowicy
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