University of Patras

About: University of Patras is a education organization based out in Pátrai, Greece. It is known for research contribution in the topics: Population & Catalysis. The organization has 13372 authors who have published 31263 publications receiving 677159 citations. The organization is also known as: Panepistímio Patrón.

Wettability and interfacial interactions in bioceramic-body-liquid systems

Abstract: Wetting experiments, by the sessile drop technique, were carried out at 37°C in air to determine the surface and interfacial interactions that take place in various solid bioceramics based on Al2O3, ZrO2(YPZ), SiO2, and TiO2 in contact with water, Ringer solution, artificial synovial fluid, calf serum, human plasma, and whole blood (+ EDTA). The surface energy of the liquids was measured by the ring method. The calculated values of the energy of interaction (work of adhesion) reveal that intermolecular forces act across the solid-liquid interfaces. The contribution of the dispersion and polar interactions to the surface energy of the polar liquids and the pure or mixed oxides was determined assuming that in the system of Mn-steel-liquids only dispersion forces act at the interface. It was found that the contribution of the polar interactions to the energy of interaction at the solid-liquid interface increases with the glassy phase content of the oxide that causes reduction of the measured contact angle. © 1995 John Wiley & Sons, Inc.

Web‐shoppers and non‐shoppers: compatibility, relative advantage and demographics

Abstract: This study investigated differences between Web‐shoppers and non‐shoppers, in terms of compatibility, relative advantage and demographics. Stepwise discriminant analysis was applied on a sample of 165 personally interviewed consumers, which showed that compatibility and relative advantage were overall successful, whereas, demographics were unsuccessful, in distinguishing Web‐shoppers from non‐shoppers. Significant variables included three factors of compatibility (use of direct shopping; use of Web browsing activities at home; and use of Web browsing activities at the office), and two factors of relative advantage (motives; and impediments). Managerial implications for targeting prospective Web‐shoppers and designing better‐grounded consumer Web‐marketing strategies are also discussed, together with study limitations and directions for future research.

Relative risk of cancer in sonographically detected thyroid nodules with calcifications.

Abstract: Purpose The aim of this prospective study was to evaluate the significance of sonographically detected thyroid calcifications in the diagnosis of thyroid cancer. Methods One hundred eighty-eight patients with thyroid disease, including 37 with thyroid cancer, were included in the study. Each patient underwent preoperative, high-resolution sonography to evaluate the thyroid gland for the presence of calcifications. Results The highest incidence of calcification was found in thyroid cancer (54%), followed by multinodular goiter (40%), solitary nodular goiter (14%), and follicular adenomas (12%). The incidence of cancer was significantly higher in calcified nodules (29%) than in noncalcified nodules in the entire group (14%) (p = 0.019), with a relative risk of 2.5. In the group of solitary thyroid nodules, the incidence of cancer in the calcified nodules (55%) was higher than in the nodules without calcification (23%) (p = 0.016). Multiple noncalcified thyroid nodules harbored cancer in only 5% of cases. Compared with multiple noncalcified thyroid nodules, the solitary calcified nodules demonstrated a relative risk of 22.8. In both the solitary and multiple nodules, the relative risk in the presence of calcification was about the same, around 4. Patients younger than 40 years with calcified nodules constituted a high-risk group, with a relative risk of 3.8 versus 2.5 in patients older than 40 years with calcified nodules. Conclusions The detection of thyroid calcifications by sonography is diagnostically valuable, especially in cases involving a solitary nodule or a young person. The presence of calcifications in these cases should raise the suspicion of malignancy. The low incidence of cancer in patients with multiple noncalcified thyroid nodules suggests that a more conservative approach may be appropriate in such cases. © 2000 John Wiley & Sons, Inc. J Clin Ultrasound 28:347–352, 2000.

Organic nitrogen of tomato waste hydrolysate enhances glucose uptake and lipid accumulation in Cunninghamella echinulata

Abstract: Aims: To investigate the effect of organic nitrogen on lipogenesis during growth of Cunninghamella echinulata on tomato waste hydrolysate (TWH) media. Methods and Results: Cunninghamella echinulata grown on a TWH medium rapidly took up glucose and produced large amounts of lipids. However, when some quantities of the organic nitrogen were removed from TWH (by acid followed by alkaline precipitation of proteins) the uptake of glucose was dramatically reduced and large quantities of fungal biomass having low lipid content were produced. Nevertheless, when glycerol was used as carbon source instead of glucose, the uptake rate as well as the biomass production and the lipid accumulation processes were unaffected by the TWH organic nitrogen removal. Finally, when the fungus was grown on a glucose supplemented TWH medium that contained no assimilable organic nitrogen (after further precipitation of proteins with methanol), the produced biomass contained non-negligible quantities of lipids, although glucose uptake remained low. Lipid analysis showed that the produced lipids comprised mainly of neutral lipids, which were preferentially consumed during lipid turnover. Lipid production on the original TWH medium having glucose as carbon source was 0·48 g of lipid per gram of dry biomass, corresponding to 8·7 g of lipid per litre of growth medium. The produced lipids contained 11·7%γ-linolenic acid (GLA), hence the GLA yield was more than 1 g l−1. Conclusions: Organic nitrogen compounds found in TWH favour glucose (but not glycerol) uptake and lipid accumulation in C. echinulata. Significance and Impact of the Study: Agro-industrial wastes containing organic nitrogen, such as tomato waste, are produced in vast amounts causing severe environmental problems. These wastes could be used as fermentation feedstock to produce microbial lipids.