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the point of view of the patient. Internal factors include species, breed, sex, age, stress, disease, physical activity, pregnancy and stage of lactation, while external factors include treatment (e.g., administration of medication), environmental
During the exponential growth phase of Penicillium chrysogenum NCAIM 00237 the effective conversion of glucose and O2 to gluconate and H2O2 by glucose oxidase (GOX) was the most likely source of intracellular ROS measured. In glucose-supplemented autolysing cultures, the increased of intracellular ROS concentration was attributed to respiration in the absence of any significant GOX activity. The induction of GOX and catalase by glucose and H2O2 was clearly age-dependent in P. chrysogenum. In ageing cryptic growth phase cultures, superoxide dismutase and cyanide-resistant respiration were the major elements of antioxidative defence but these activities were insufficient to prevent the progressive accumulation of ROS and the concomitant decrease in cell vitality.
Summary
The hydration products in two aged cement pastes (DTA/DTG/TG) were compared with those in fresh ones (static heating, SH) and were also studied by mass spectrometry (MS), IR and thermo XRD-analysis. The products considered here were: the sorbed water, the CSH gel including hydrates, portlandite, calcite, aragonite and vaterite. Except carbonates their content was higher in the stronger paste C-43, than in C-33, but lowered with ageing (only the CSH gel water remained approximately unchanged). The sorbed water content became with time lower and similar in both pastes (it evaporated up to 155-185C in TG); the escape of the rest moved to higher temperatures (500-700C). The three DTG peaks at 200-400C indicated jennite-like phase in the CSH gel; the mass loss (155-460C) was higher on ageing due to development of organic matter, especially in C-43 (DTA, TG, IR). Portlandite content changed little and carbonate content increased considerably. They decomposed in air at 470 and 720-740C, in argon at 450 and 680-710C and in vacuum at 400 and 630C, respectively (DTG peak, XRD). Between 500 and 700C the simultaneous evolution of H2O and CO2was observed by MS, which is attributed to dehydroxylation of jennite-like phase and/or to decomposition of some carbonate hydrate and/or hydrocarbonate (three peaks on CO2evolution curve, MS). The d(001) peak of portlandite exceeded the nominal value and will be analyzed separately.
, Chae, Lee, & Kim, 2007 ). Several core motivations for gambling might be operative in older adult populations. Recent increases in the availability of gambling products and services (including online gambling), combined with age-related physical
This paper deals with the archaeological material of a Scythian Age settlement excavated near Nagytarcsa in 2007. Located on the higher terrace of a stream, the site represents a characteristic lowland, hamlet-like settlement of the Vekerzug culture, where animal husbandry played an important role in subsistence. Based on diagnostic ceramic finds and radiocarbon dating the settlement can be assigned to the Ha D2 period. The archaeological description, as well as the evaluation of settlement features and finds, is supplemented with a detailed petrographic analysis with an emphasis on wheel-thrown and Hallstatt type ceramics. The petrographic and geochemical analysis of the sherds and sediments collected on the site aim to confirm archaeological interpretations in order to determine the provenance of the ceramics and to assess whether their technological characteristics suggest specialization in production.
Vitrification phenomena and further structural relaxation processes or physical ageing occurring in the isothermal curing reaction of an epoxy resin are studied by Differential Scanning Calorimetry (DSC). The vitrification time,t v , the limiting conversion degree and the limiting glass transition temperature (T g) are evaluated at curing temperatures (T c) between 30 and 100‡C. The dependence of limitingT g withT c permits the determination of the maximumT g of the resin (109‡C). The physical ageing, which appears as the the last step of curing reaction for curing times above to vitrification, is analyzed through the endothermic peak superposed to the glass transition temperature. The results obtained in partially reticulated resin show the kinetics of the physical ageing to slow down asT c increases, as a consequence that the segmental mobility is reduced.
Abstract
Simulation of waterlogged archaeological woods was carried out by immersion of fir and chestnut wood samples into sea water at different temperatures (room temperature and 40°C). The effects of metals in contact with woods were simulated by inserting in some specimens of the two types of wood copper or iron nails, the most important metals from the archaeological point of view. The effects of this ageing simulation on woods were studied by different characterization methods. At first we have performed gravimetric analyses, controlling the mass increase of immersed wood in function of the time of immersion and the temperature of the bath. Then, thermogravimetry, differential thermal analysis, differential scanning calorimetry in oxygen flux were used. The alteration of wood was observed by means of the peak temperatures of DTA, DTG and DSC variation and by the mass losses observed during heating, evaluated on the basis of the measured thermal data. The samples were woods powder obtained by milling. Complementary characterization of the woods was performed by evaluating the crystallinity of cellulose by means of X-ray powder diffraction. The change in colour of woods during ageing was checked by means of spectrophotometric measurements in the visible region. X-ray fluorescence was used to investigate the penetration of metals into wood samples. An artificial ageing treatment with NaOH and O3 was also performed. Finally, a comparison between the effects of artificial alteration realised in our specimens and natural degradation observed in archaeological woods, was performed.
H. Petrovitch 2001 Current evidence for neuroprotective effects of nicotine and caffeine against Parkinson's disease Drugs Aging 18 797
Abstract
To reveal the fire injuring of parchment, the changes in the thermal behaviour of some goat parchments, obtained from skins originating from different animals, as a result of thermal aging were determined by thermal analysis methods (DSC; simultaneous TG/DTG, DSC; micro hot table (MHT)). Thermal aging of parchments was revealed to bring about the decrease in shrinkage temperature, absolute value of enthalpy of denaturation in water and some changes in non-isothermal parameters characteristic for dehydration process in static air atmosphere. The results obtained by DSC analysis performed in N2 and O2 flows as well as those obtained by simultaneous TG/DTG, DSC analyses have shown that both softening (melting) process parameters and parameters of thermo-oxidative processes have not been changed by thermal ageing. The results obtained by thermal analysis methods were correlated with those obtained by microscopic investigation of parchment samples immersed in water and scanning electron microscopy (SEM). The application of these microscopic techniques has revealed the morphology changes in the investigated parchments as a result of thermal degradation.
stress with increasing age. For instance, Pizent et al. (2010) assessed serum Cu, Se, and Zn in elderly humans with metabolic syndrome, which is associated with the occurrence of cardiovascular diseases. They found no clear evidence of a relationship
