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Abstract
It has been suggested that several age-related neurological diseases such as Alzheimer's disease and amyotrophic lateral sclerosis may be related to environmental toxins. Bulk sample multielement analyses by INAA alone are not adequate to define the role of trace elements in these diseases. A multitechnique approach has been developed that incorporates 14 MeV, instrumental reactor, radiochemical, and pre-irradiation chemical neutron activation analysis, together with laser microprobe mass spectrometry. The analytical scheme is able to provide bulk or protein normalized elemental concentrations, as well as microstructural, cellular, and subcellular localization information.
Az Eurostat előrejelzése szerint az EU27 népességének 45,52%-a lesz 2040-ben 65 év feletti. A nagyarányú nyugdíjaztatások következtében hiány lesz a magasan kvalifikált munkaerőből csaknem valamennyi területen. Amikor 2050-re átlagosan már csak két aktív dolgozó jut egy nyugdíjasra, a jóléti ellátások Európa-szerte drasztikusan hanyatlani fognak, és növekszenek majd az egészségügyi és nyugdíjrendszerek kiadásai. Amennyiben az európai gazdaság az elkövetkező években magához tér, továbbra is szüksége lesz mérnökökre, orvosokra, különféle szakemberekre, akikből máris számos országban súlyos hiány mutatkozik. A problémát súlyosbítja, hogy a felsőoktatás általában nem követi a munkaerőpiac szükségleteit és voltaképpen növeli a fiatal diplomások munkanélküliségét. Az elöregedő európai társadalom szakemberszükségletét várhatóan néhány évtized múlva más forrásokból kell biztosítani, és erre kínálkozik a hatalmassá növekedett indiai felsőoktatás; Indiában ma is mintegy 120-140 millióan beszélnek jól angolul. Azonban az indiai felsőoktatás mai helyzete számos problémát mutat, amelyeket várhatóan az elkövetkező évtizedekben leküzdenek és keletkezik majd ott jól képzett munkaerő, amely bárhol a világon képes munkát vállalni, ehhez azonban arra van szükség, hogy a saját gondjait is megoldó európai felsőoktatás rendszeres és szoros munkakapcsolatot építsen ki az indiai felsőoktatási intézményekkel annak érdekében, hogy kölcsönösen megismerjék az elvárásokat és lehetőségeket.
Foreword Dear Reader, This issue of Developments in Health Sciences is dedicated to the topics of ageing humans and ageing societies. We think that these topics are very important and relevant because
Abstract
Concentrations of 17 elements in fingernails of 92 control individuals with ages ranging from 4 months to 93 years living in a relatively non-industrial environment were determined by instrumental neutron activation analysis (INAA). Statistical analysis demonstrated several different patterns of trace element correlation with age and sex. Bromine, Co, Cr, Fe, Na and Sb were found to be negatively correlated (p<0.05) with age, while Zn was positively correlated (p<0.05). Silver, Au, Se, and Zn concentrations were found to be higher in females than in males. Males had higher concentrations of Na and K than females. Significant interelement correlations were also observed. The age and sex variations observed should prove to be useful in the proper interpretation of elemental imbalances associated with degenerative neurological diseases, especially in view of recent reports that markers for AD have been detected in external tissue.
References Average effective age of retirement versus the official age in 2012 in OECD countries ( 2012 ): http://www.oecd.org/els/emp/Summary_2012_values.xls. Accessed: 07
older people . Age Ageing 39 , 412 – 423 ( 2010 ) 10.1093/ageing/afq034 2. Park , SW , Goodpaster , BH
age until about 70 years of age with some decrease in the oldest old probably due to healthy survival bias [ 3 ]. As a consequence of continuously increasing life expectancy in the last decades, the proportion of elderly people is becoming higher and
Ageing of wet-synthesized oxide powders
Role of surface carbonation, effect on sintering, restoration
Abstract
Wet chemical synthesis of precursor oxide ceramics is a method to obtain small particulate powders. Such powders are far more prone to ageing in air than more traditional precursors. Thermogravimetric analysis is used to highlight the species responsible for the ageing of ceramic precursors. Indeed water and carbon dioxide are observed to evolve from aged powders. Ceramics obtained from aged precursors can reach a very low final density with respect to the theoretical value. A large degree of the original sintering properties can be recovered after washing the aged powders with ethanol in a basic medium.
Society for Maternal-Fetal Medicine.) Obstet. Gynecol., 2013, 121 (5), 1122–1133. Gardosi, J., Francis, A.: Adverse pregnancy outcome and association with small for gestational age birthweight by customized and
Artificial ageing of double base rocket propellant
Effect on dynamic mechanical properties
Abstract
The ageing of double base rocket propellants (DB rocket propellants), which is a consequence of chemical reactions and physical processes that take place over time, has significant effect on their relevant properties (e.g. chemical composition, mechanical properties, ballistic properties, etc.). The changes of relevant properties limit the safe and reliable service life of DB rocket propellants. This is the reason why numerous research efforts are devoted to finding out reliable methods to measure the changes caused by ageing, to assess the quality at a given moment of time, and to predict remaining life-time of DB rocket propellants. In this work we studied dynamic mechanical properties of DB rocket propellant artificially aged at elevated temperatures, in order to detect and quantify changes in dynamic mechanical properties caused by the ageing. Dynamic mechanical properties were studied using dynamic mechanical analyser (DMA). The results obtained have shown that the ageing causes significant changes of DMA curve’s shape and positions. These changes are quantified by following some characteristic points on DMA curves (e.g. glass transition temperatures; storage modulus, loss modulus and tanδ at characteristic temperatures, etc.). It has been found out that the most sensitive parameters to the ageing process are: storage modulus at viscoelastic and softening region, peak width and height on loss modulus curve, glass transition and softening temperature, and tanδ at viscoelastic region.
