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991.
Dimitrios S. Lenas Dimitrios J. Triantafillou Soumela Chatziantoniou Cosmas Nathanailides 《Journal für Verbraucherschutz und Lebensmittelsicherheit》2011,19(3):435-440
Historically farmed fish were frequently found to exhibit a lower ratio of n3/n6 fatty acids compared to wild fish. This study
compares the proximate and fatty acid composition of wild and cultured gilthead sea bream fish from a lagoon in NW Greece.
Wild fish contained less fat and showed different fatty acid profiles. Farmed fish exhibited threefold higher concentrations
of linoleic acid (C18:2n-6) in muscle and twofold in visceral fat. Their muscle tissue contained higher levels of saturated
fatty acids and higher ratios of eicosapentaenoic acid/docosahexaenoic acid (0.49 ± 0.04 vs. 0.03 ± 0.01; Ρ < 0.001). Wild fish exhibited lower levels of muscle n-3 fatty acids (15.87 ± 0.82 vs. 19.89 ± 1.06; P < 0.001) but a higher ratio of n-3/n-6 (2.22 ± 0.14 vs. 1.64 ± 0.10, Ρ < 0.001). These results emphasize the need to further explore dietary manipulation of fatty acid content as a method of improving
the fatty acid profile and maximise the health benefits of consuming farmed fish. 相似文献
992.
In context of the implementation of the EU Water Framework Directive, conventional hierarchies and dominant logics in the metropolitan area of Volos, Greece, are challenged indirectly, in a “Trojan-horse” like way. The basic characteristic of the water sector in Volos Urban Area is the absolute dominance of centralized services (Municipal Enterprise for Water and Sewage). However, the intense interest of new actors (private companies, NGOs, University and Research Institutes, etc.) has led to the establishment of an informal and voluntary social network. The paper evaluates the role of an informal social network as a new form of governance in the framework of spatial development that has emerged in the shadow of an existing hierarchy. The basic issues highlighted are:
- The challenge to hierarchical decision making structures in the water sector through an informal and voluntary social network.
- The learning processes and knowledge forms that new actors bring to and acquire in such forms of network practices (e.g. contribution to public awareness, mobilisation of local knowledge).
993.
Minkyong Kim Zhen Liu Srinivasan Parthasarathy Dimitrios Pendarakis Hao Yang 《Wireless Networks》2012,18(5):535-550
As mobile nodes roam in a wireless network, they continuously associate with different access points and perform handoff operations. Frequent handoffs performed by a mobile device may have undesirable consequences, as they can cause interruptions for interactive applications and increase the energy usage of mobile devices. While existing approaches to this issue focus entirely on improving the latency incurred by individual handoffs, in this paper, we initiate a novel approach to association control of mobile devices with the goal of reducing the frequency of handoffs for mobile devices. We study the handoff minimization problem across multiple dimensions: offline versus online where the complete knowledge of mobility patterns of users is known in advance or unknown respectively; capacity constrained versus unconstrained access points, which imposes limits on the number of mobile devices which could be associated with a given access point at any given point in time; group mobility versus arbitrary mobility of users, which are contrasting ways to model the mobility patterns of the mobile users. We consider various combinations of the above dimensions and present the following: (1) optimal algorithms, (2) provably-good online and offline approximation algorithms, (3) complexity (NP-Completeness) results, and (4) a practical heuristic which is demonstrated to work well on real network traces. 相似文献
994.
Iraklis Anagnostopoulos Alexandros Bartzas Iason Filippopoulos Dimitrios Soudris 《Design Automation for Embedded Systems》2012,16(4):339-361
Network-on-Chip (NoC) has been recognized as the new paradigm to interconnect and organize a high number of cores. NoCs address global communication issues in System-on-Chips (SoC) involving communication-centric design and implementation of scalable communication structures evolving application-specific NoC design as a key challenge to modern SoC design. In this paper we present a SystemC customization framework and methodology for automatic design and evaluation of regular and irregular NoC architectures. The presented framework also supports application-specific optimization techniques such as priority assignment, node clustering and buffer sizing. Experimental results show that generated regular NoC architectures achieve an average of 5.5 % lower communication-cost compared to other regular NoC designs while irregular NoCs proved to achieve on average 4.5×higher throughput and 40 % network delay reduction compared to regular mesh topologies. In addition, employing a buffer sizing algorithm we achieve a reduction in network’s power consumption by an average of 45 % for both regular and irregular NoC design flow. 相似文献
995.
Constantina Nasopoulou Haralabos C. Karantonis Despina N. Perrea Stamatios E. Theocharis Dimitrios G. Iliopoulos Constantinos A. Demopoulos Ioannis Zabetakis 《Food chemistry》2010
The aim of this study was to investigate whether the fish lipid extracts have in vivo anti-atherogenic properties in hypercholesterolaemic rabbits. Fish oil extracts were obtained from cultured gilthead sea bream (Sparus aurata) and, for the in vivo experiment, 12 healthy male New Zealand rabbits of specific weight and age were used, which were randomly divided into two groups of six animals each and were given specific diets for 45 days. Group A was given an atherogenic diet, while group B was given an atherogenic diet enriched with Gilthead Sea Bream Polar Lipids (GSBPL). 相似文献
996.
The uptakes of endoglucanase and endoxylanase by soybean were studied by measuring the fluorescent intensity of a carboxyfluorescein. The disappearance rates of these enzymes from solution were compared with predictions from different models. The Freundlich model provided the best fit for our data. Enzyme concentration in the solution did not change significantly after 11 d, and therefore it was assumed that equilibrium was reached. Average mass transfer coefficient was calculated for both endoglucanase and endoxylanase from the plot of the rate of uptake against (C(l av) -Cl*) and a value of 4 x 10(-5) ms(-1) was obtained. K value was used to calculate the effective diffusivities of the two enzymes assuming a slice. It is found that K was asymptotic with long residence times, and a value of 4.8 x 10(-10) m2 s(-1) was obtained. 相似文献
997.
The fresh whey cheeses Myzithra, Anthotyros, and Manouri were inoculated with Aeromonas hydrophila strain NTCC 8049 (type strain) or with an A. hydrophila strain isolated from food (food isolate) at levels of 3.0 to 5.0 x 10(2) CFU/g of cheese and stored at 4 or 12 degrees C. Duplicate samples of cheeses were tested for levels of A. hydrophila and pH after up to 29 days of storage. At 4 degrees C, A. hydrophila grew in Myzithra and Anthotyros with a generation time of ca. 19 h, but no growth was observed in Manouri. In Myzithra, average maximum populations of 8.87 log CFU/g (type strain) and 8.79 log CFU/g (food isolate) were recorded after 20 and 22 days of storage at 4 degrees C, respectively. The average maximum populations observed in Anthotyros stored at 4 degrees C were 6.72 log CFU/g (food isolate) and 6.13 log CFU/g (type strain) and were observed after 15 and 16 days of storage, respectively. A. hydrophila grew rapidly and reached high numbers in cheeses stored at 12 degrees C. The average generation times were 3.7 and 3.9 h (Myzithra), 4.1 and 6.1 h (Anthotyros), and 8.0 and 9.2 h (Manouri) for the type strain and the food isolate, respectively. Among the different whey cheese trials, the highest A. hydrophila population recorded (10.13 log CFU/g) was in Myzithra that had been inoculated with the food isolate after 8 days of storage at 12 degrees C. To prevent A. hydrophila growth in whey cheeses, efforts must be focused on preventing postprocessing contamination and temperature abuse during transportation and storage. 相似文献
998.
Jankovic L Gournis D Trikalitis PN Arfaoui I Cren T Rudolf P Sage MH Palstra TT Kooi B De Hosson J Karakassides MA Dimos K Moukarika A Bakas T 《Nano letters》2006,6(6):1131-1135
Superconducting low dimensional systems are the natural choice for fast and sensitive infrared detection, because of their quantum nature and the low-noise, cryogenic operation environment. On the other hand, monochromatic and coherent electron beams, emitted from superconductors and carbon-based nanostructured materials, respectively, are significant for the development of electron optical systems such as electron microscopes and electron-beam nanofabrication systems. Here we describe for the first time a simple method which yields carbon nanotubes encapsulating single crystalline superconducting tin nanowires by employing the catalytic chemical vapor deposition method over solid tin dioxide. The superconducting tin nanowires, with diameters 15-35 nm, are covered with well-graphitized carbon walls and show, due to their reduced diameters, a critical magnetic field (Hc) more than 30 times higher than the value of bulk metallic tin. 相似文献
999.
Paulina Escandon Angela Liu Sarah E. Nicholas Asher Khan Kamran M. Riaz Dimitrios Karamichos 《International journal of molecular sciences》2022,23(8)
Salivary exosomes have demonstrated vast therapeutic and diagnostic potential in numerous diseases. This study pioneers previously unexplored roles of SE in the context of corneal wound healing by utilizing primary corneal stromal cells from healthy (HCFs), type I diabetes mellitus (T1DMs), type II DM (T2DMs), and keratoconus (HKCs) subjects. Purified, healthy human SEs carrying tetraspanins CD9+, CD63+, and CD81+ were utilized. Scratch and cell migration assays were performed after 0, 6, 12, 24, and 48 h following SE stimulation (5 and 25 µg/mL). Significantly slower wound closure was observed at 6 and 12 h in HCFs with 5 μg/mL SE and T1DMs with 5 and 25 μg/mL SE. All wounds were closed by 24-hour, post-wounding. HKCs, T1DMs, and T2DMs with 25µg/mL SE exhibited a significant upregulation of cleaved vimentin compared to controls. Thrombospondin 1 was significantly upregulated in HCFs, HKCs, and T2DMs with 25 µg/mL SE. Lastly, HKCs, T1DMs, and T2DMs exhibited a significant downregulation of fibronectin with 25 μg/mL SE. Whether SEs can be utilized to clinical settings in restoring corneal defects is unknown. This is the first-ever study exploring the role of SEs in corneal wound healing. While the sample size was small, results are highly novel and provide a strong foundation for future studies. 相似文献
1000.
L-Arginine:glycine amidinotransferase (AGAT) catalyzes the formation of L-homoarginine (hArg) and L-ornithine (Orn) from L-arginine (Arg) and L-lysine (Lys): Arg + Lys ↔ hArg + Orn; equilibrium constant KhArg. AGAT also catalyzes the formation of guanidinoacetate (GAA) and Orn from Arg and glycine (Gly): Arg + Gly ↔ GAA + Orn; equilibrium constant KGAA. In humans, pharmacological hArg is metabolized to Lys. Low circulating and low excretory concentrations of hArg are associated with worse outcomes and mortality in the renal and cardiovascular systems. The metabolism and pharmacology of hArg have been little investigated. In the present study, we investigated the effects of pharmacological hArg (i.p., 0, 20, 220, 440 mg/kg at time point 0 min) on amino acids homeostasis in a rat model of isoprenaline-induced takotsubo cardiomyopathy (i.p., 50 mg/kg at time point 15 min). We measured by gas chromatography-mass spectrometry free and proteinic amino acids, as well as the polyamines putrescine and spermidine in the heart, lung, kidney, and liver of ten rats sacrificed at various time points (range, 0 to 126 min). hArg administration resulted in multiple changes in the tissue contents of several free and proteinic amino acids, as well as in the putrescine-spermidine molar ratio, an indicator of polyamines catabolism. Our results suggest that Lys and Arg are major metabolites of pharmacological hArg. Kidneys and heart seem to play a major metabolic role for hArg. Circulating Lys does not change over time, yet there is a considerable interchange of free Lys between organs, notably kidney and heart, during the presence of isoprenaline in the rats (time range, 15 to 90 min). Antidromic changes were observed for KhArg and KGAA, notably in the heart in this time window. Our study shows for the first time that free hArg and sarcosine (N-methylglycine) are positively associated with each other. The acute effects of high-dosed hArg administration and isoprenaline on various amino acids and on AGAT-catalyzed reaction in the heart, lung, kidney, and liver are detailed and discussed. 相似文献