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Lakatta, E. G., Levy, D.: Arterial and cardiac aging: major shareholders in cardiovascular disease enterprises. Part I: Aging arteries: a “set up” for vascular disease. Circulation, 2003, 107
Abstract
Shape memory alloys (SMA) are interesting for applications in damping of civil engineering structures. To achieve the SMA as a guaranteed material for damping of structures requires a reliability study of the static and dynamic properties adapted to each type of application. Here we present static (temperature and time effects) and dynamic actions in pseudo-elastic NiTi SMA. We concern with long time effects of temperature and time mainly in beta phase. NiTi results are presented, including measurements of electrical resistance as a function of temperature and time, DSC to −80°C (TA Instruments), non-conventional conduction calorimetry (to 80 K), and several X-ray diffraction spectra at different temperatures. Diffusion effects are present, and all the measurements show that transformation temperatures change with time of aging even at moderate temperatures (i.e., near 100°C), depending on time and temperature. It is possible to visualize the diffusion change in the R phase transformation via classical X-ray characterization. We include some results of pre-stressing effects applying the stress at different zones of the hysteresis cycle. The experimental analysis shows that coupling between stress and temperature enhances the changes. For long times (10, 20 years) and direct sunny actions, more deep analysis is required. Finally, some dynamic effects in cycling affecting the SMA creep are outlined.
During the aging process of mammals first a phase of obesity and increased adiposity is observed in middle-aged subjects, then anorexia and loss of body weight (sarcopenia) at old age. A possible agedependence of the anorexigenic alpha-melanocyte-stimulating-hormone (alpha-MSH) in these regulatory changes was studied. Male Wistar rats aged 6–8 weeks (juvenile), 3–4 months (young adult), 6 and 12 months (middle-aged), and 24–26 months (old) were equipped with chronic cannula to the lateral cerebral ventricle. The effect of 5 μg alpha-MSH injected through the cannula was analyzed on food intake evoked by 24-h food deprivation. Juvenile rats seemed almost resistant to alpha-MSH (21.9% suppression). In young adults alpha-MSH suppressed food intake by 68.7%. However, the alpha-MSH-induced anorexia was significantly less pronounced in middle-aged (55.7% or 26.4% in rats aged 6 or 12 months, respectively), and much more pronounced (73.3%) in old rats. The adiposity (judged by the relative amount of perirenal fat) increased until middle-age, but did not change between middle-age and old-age. It is concluded that changes in alpha-MSH responsiveness possibly contribute to both the age-related obesity in middle-aged rats and to the anorexia of old ones: first the adiposity then the age may be the important factor.
Abstract
Rousseau is generally associated with the eighteenth century French philosophes in what Peter Gay called “The Party of Humanity.”While it is true that Rousseau shared many of the progressive political and philosophical ideas of that group of enlightened figures, he parted company with them on basic issues of theology and religion. This is apparent in the reading of Rousseau's published works - where his religious instincts especially, separate him from the radical wing of the French Enlightenment. There is an enormous distance between his “Profession du vicaire savoyard”and Diderot's Penses philosophiques. It is in his great correspondence, however, that one may see just how Rousseau differed from his colleagues in the struggle against religious and political obscurantism. In his letters he discourses brilliantly on basic metaphysical questions and proposes intuition over reason as a more serious intellectual modality. Beyond even those philosophes such as Voltaire, who embraced a kind of vapid deism, Rousseau uses his correspondence to endorse a mystical conception of the universe in which emotion, imagination and feeling are inextricably bound up. In his survey of contemporary philosophical ideas Rousseau expresses as much scorn for intolerant religious dogma as he does for the extreme expressions of atheism. There are many letters in which he argues against the materialist interpretation of matter and demands of the atheist school convincing intellectual proofs for their theses. In the correspondence Rousseau has a great deal to say about his own conception of God, immortality and the soul. His eschatology is, of course, different from the conventional Christian one; he cannot or will not accept the idea of eternal damnation. In his discussion of religion in the letters Rousseau ranges far and wide; he considers, interalia, extra terrestrial life, the idea of free will, the purpose of rapture and theodicy. In this last arena, where a just God is seen to permit evil in the world, Rousseau waxes eloquent in trying to solve this age-old theological quandary. He does so by exploring definitions of the word evil and emphasizing the orderly nature of the universe. In this context, Rousseau, a master of the religious dialectic, reduces the problem of evil and death through an astute linguistic approach. Rousseau's final plea, as extracted from his correspondence, is that human beings must recognize the limits of reason as an instrument capable of solving all the metaphysical problems.
study on ageing, and one was a cross-sectional study. The included studies cover areas of three continents (Europe, Asia, and North America) ( Fig. 2 ). The samples of most studies come from the population of older adults (aged older than 55 years
References 1. E.G. Lakatta D. Levy 2003 Arterial and cardiac aging: major
Narrative recall in the elderly
Content, fluency and speech errors in the narrative speech of young, young-old and old-old speakers
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involvement in aging. Pathophysiology and therapeutic implications. Drugs Aging 3, 60-80. Free radical involvement in aging. Pathophysiology and therapeutic implications Drugs Aging
Graham, S.: Old age was secret of modern humans’ success. Scientific American, 2004, 291 , 115–116. Graham S. Old age was
Thermal characterization of gelatinized binary rice starch-water and ternary starch-sugar-water gels before and after aging was carried out using differential scanning calorimetry. The glass transition temperature of the maximally freeze-concentrated solution (T′g) in both fresh and aged gels was observed to decrease progressively with increasing sugar concentration. Aging of the gels generally shiftedT′g to higher temperatures, but had little or no effect on the ice melting peak temperature (T m). The presence of various sugars could either accelerate or retard starch (amylopectin) recrystallization, depending on the type and concentration of sugar, as well as on starch/water ratio. A hypothesis based on the dual antiplasticizing-plasticizing effects of sugars was postulated to explain the observed effects. Of the sugars studied, xylose and fructose appeared to display exceptional retardative and accelerative effects, respectively, on retrogradation.
