Relevant bibliographies by topics / Secondary ageing

Academic literature on the topic 'Secondary ageing'

Author: Grafiati
Published: 4 June 2021
Last updated: 20 February 2023

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Journal articles on the topic "Secondary ageing"

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Massazza, M., G. Riontino, A. Dupasquier, R. Ferragut, A. Somoza, and P. Folegati. "Secondary ageing in Al-Cu-Mg." Philosophical Magazine Letters 82, no. 9 (September 2002): 495–502. http://dx.doi.org/10.1080/09500830210153896.

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Zhang, Xingpu, Meng Liu, Jiangwei Wang, Jixue Li, and John Banhart. "Combined effect of Sn addition and pre-ageing on natural secondary and artificial ageing of Al–Mg–Si alloys." Journal of Materials Science 57, no. 3 (January 2022): 2149–62. http://dx.doi.org/10.1007/s10853-021-06654-y.

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AbstractBoth Sn addition and pre-ageing are known to be effective in maintaining the artificial ageing potential after natural ageing of Al–Mg–Si alloys. In this study, the combined effects of Sn addition and pre-ageing at 100 °C or 180 °C on natural secondary ageing and subsequent artificial ageing of an alloy AA6014 were investigated using hardness, electrical resistivity, differential scanning calorimetry and transmission electron microscopy characterizations. It is found that pre-ageing can suppress natural secondary ageing and improve the artificial ageing hardening kinetics and response after 1 week of natural secondary ageing in both alloys with and without Sn addition. The effect of pre-ageing at 100 °C is more pronounced in the Sn-free alloy while the combination of pre-ageing at 180 °C and adding Sn shows superiority in suppressing natural secondary ageing and thus avoiding the undesired hardening before artificial ageing. Moreover, when natural ageing steps up to 8 h are applied before pre-ageing at 100 °C, the effect of pre-ageing in Sn-added alloy can be further improved. The influence of Sn on vacancies at different ageing temperatures is discussed to explain the observed phenomena. Graphical abstract
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Buha, J., R. N. Lumley, and A. G. Crosky. "Secondary ageing in an aluminium alloy 7050." Materials Science and Engineering: A 492, no. 1-2 (September 2008): 1–10. http://dx.doi.org/10.1016/j.msea.2008.02.039.

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Yin, M., D. D. Risanti, Jiang Hua Chen, and Sybrand van der Zwaag. "A TEP Study on the Microstructural Development in AA2024 during Interrupted Ageing." Advanced Materials Research 89-91 (January 2010): 669–74. http://dx.doi.org/10.4028/www.scientific.net/amr.89-91.669.

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This work utilizes thermoelectric power (TEP) measurement to track secondary precipitation during the interrupted ageing cycle for AA2024 alloys as well as the subsequent re-ageing cycle. Clear evidences of secondary precipitation were observed which affect the further precipitation sequence during re-ageing. The TEM results confirm that S and S” phases co-exist upon re-ageing.
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SCOTT, THEA, VICTOR MINICHIELLO, and COLETTE BROWNING. "Secondary school students' knowledge of and attitudes towards older people: does an education intervention programme make a difference?" Ageing and Society 18, no. 2 (March 1998): 167–83. http://dx.doi.org/10.1017/s0144686x98006874.

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It is now increasingly recognised that if we are to combat ageism the attitudes and knowledge of young people need to be more positively constructed so that they do not hold stereotypic views of ageing. This study evaluates the impact of an educational intervention programme on the attitudes and knowledge of students aged 17–18 years from six secondary schools in Melbourne, Australia. Using Palmore's Facts on Aging Quiz to assess knowledge about and attitudes towards ageing in a quasi-experimental pre-test and post-test design, the results reveal that, in general, students hold low knowledge about older people and negative attitudes about ageing. However, the pre-test mean knowledge scores differed significantly between male and female students and across the various schools, and students who had greater contact with grandparents possessed slightly more knowledge. The post-test results show that the intervention education programme was not successful in raising the student's level of knowledge. The results also show that, in general, the students hold negative attitudes towards older people and that there was little change in their attitudes following the intervention programme. The paper discusses the implications of these results regarding curriculum development in education programmes on ageing intended for young people.
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Peacock, L. E., and F. Wright. "Serotonin syndrome secondary to tramadol and citalopram." Age and Ageing 40, no. 4 (March 16, 2011): 528. http://dx.doi.org/10.1093/ageing/afr017.

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Hannink, R. H. J., O. Schmidt, and J. R. Griffiths. "Subeutectoid Ageing of Secondary Precipitates in Mg-PSZ." Key Engineering Materials 53-55 (January 1991): 738–43. http://dx.doi.org/10.4028/www.scientific.net/kem.53-55.738.

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Sánchez-Román, María, Gadea Autric-Tamayo, Gloria Fernandez-Mayoralas, Fermina Rojo-Perez, María Silveria Agulló-Tomás, Diego Sánchez-González, and Vicente Rodriguez-Rodriguez. "Social Image of Old Age, Gendered Ageism and Inclusive Places: Older People in the Media." International Journal of Environmental Research and Public Health 19, no. 24 (December 18, 2022): 17031. http://dx.doi.org/10.3390/ijerph192417031.

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Ageism promotes the exclusion of older people from society by generating a negative image that they also internalize. The aim of this article is to investigate older people’s social self-image, through statements broadcast on a national Spanish radio program aimed at this group. A qualitative analysis was conducted for a random sample from the sound archive for the Radio Nacional de España program Juntos Paso a Paso (Together, Step by Step) (2008–2021), using codes based on the pillars and determinants of active ageing and the three dimensions of ageism. Intercoder agreement was calculated. There were significant findings regarding ageism, gendered ageism and ageing in place, with differences according to size of municipal area. The program in question can be considered a viable secondary source for the research aim. Ageism is most commonly manifested through implicit opinions and invisibilization in family and social contexts. Care activities play a notably central role in responses related to gendered ageism. In relation to ageing in place, older people prefer their habitual environment when they have moderate care needs and accept moves to nursing homes when their needs increase.
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McFeely, Aoife, Rachael Doyle, Sean O’Riordan, Sean Connolly, and Clodagh O’Dwyer. "Severe brachial plexopathy secondary to shingles (herpes zoster)." Age and Ageing 50, no. 3 (March 26, 2021): 1001–3. http://dx.doi.org/10.1093/ageing/afab055.

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Abstract Varicella zoster reactivation (“shingles” or “herpes zoster”) usually presents as a self-limiting, unilateral, dermatomal vesicular rash in older adults. We present the case of a 73 year-old woman with unilateral brachial plexopathy, an unusual but debilitating complication of shingles. Despite treatment with intravenous acyclovir and immunoglobulin she had a marked residual motor paresis that required an upper limb rehabilitation program after discharge.
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Bodard, Quentin, Frederic Roca, Baptiste Dilly, Druesne Laurent, and Philippe Chassagne. "Acute cardiac failure secondary to senile systemic amyloidosis." Age and Ageing 45, no. 6 (April 21, 2016): 908–9. http://dx.doi.org/10.1093/ageing/afw073.

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Dissertations / Theses on the topic "Secondary ageing"

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Marvier, Allison Christina. "Effects of ageing on primary and secondary transport processes in red beet (Beta vulgaris) storage tissue." Thesis, University of Southampton, 1994. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.295952.

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Buha, Joka School of Materials Science &amp engineering UNSW. "Interrupted ageing of Al-Mg-Si-Cu alloys." Awarded by:University of New South Wales. School of Materials Science and engineering, 2005. http://handle.unsw.edu.au/1959.4/20794.

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This thesis systematically investigates the effects of a recently developed modified ageing procedure of aluminium alloys, termed the T6I6 temper, on the microstructural development and mechanical properties of the Al ??? Mg ??? Si - Cu alloy 6061. For the T6I6 temper, a conventional single stage T6 temper is interrupted by an ageing period at a reduced temperature (65??C) to facilitate secondary precipitation, before resuming the final ageing at the temperature of the initial T6 treatment. The T6I6 temper was found to cause simultaneous increases in tensile properties, hardness, and toughness as compared with 6061 T6. Al ??? Mg ??? Si ??? Cu alloys are medium strength alloys widely used in the automotive industry and their further improvement is underpinned by stringent demands for weight reduction placed on the transportation industry in recent years. The potential for further improvement of the mechanical properties was found in the control of secondary precipitation that may take place even in some fully aged alloys when exposed to reduced temperatures. The overall improvement in the mechanical properties of 6061 T6I6 was attributed to the formation of finer and more densely dispersed precipitates in the final microstructure. The refinement of precipitates was facilitated by control of the precipitation processes and gradual evolution of the microstructure throughout each stage of the T6I6 treatment. The results indicated that the concentration and the chemical environment of the vacancies controlled the precipitation processes in this alloy. Findings also show that the proportion of the different precipitate phases present in the final microstructure, as well as the amount of the solute in these precipitates, can be controlled and modified utilizing secondary precipitation. A number of analytical techniques were used in this study. The evolution of the microstructure was studied using Transmission Electron Microscopy (TEM), High Resolution TEM (HRTEM) and Three Dimensional Atom Probe (3DAP). Vacancy-solute interactions were studied using Positron Annihilation Lifetime Spectroscopy (PALS) and 3DAP. The distribution of the solute was studied using 3DAP and Nuclear Magnetic Resonance (NMR). Differential Scanning Calorimetry (DSC) was used to identify precipitation reactions and to determine the stability of vacancy-associated aggregates.
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Xu, Dapeng. "Time effects on soil behavior : a particulate-scale study on the mechanisms of secondary consolidation and ageing /." View abstract or full-text, 2006. http://library.ust.hk/cgi/db/thesis.pl?CIVL%202006%20XU.

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Marceau, Ross Kevin William. "Design in Light Alloys by Understanding the Solute Clustering Processes During the Early Stages of Age Hardening in Al-Cu-Mg Alloys." University of Sydney, 2008. http://hdl.handle.net/2123/4008.

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Doctor of Philosophy (PhD)
The evolution of atomistic-level nanostructure during the early stages of both standard, high-temperature T6 heat treatment, and low-temperature secondary ageing after interruption of the former (T6I4), has been investigated in rapid hardening Al-Cu-Mg alloys using a variety of microscopy and microanalytical techniques, including transmission electron microscopy (TEM), positron annihilation spectroscopy (PAS) and atom probe tomography (APT). In order to carry out this objective, quantitative data-analysis methods were developed with respect to new cluster-finding algorithms, specifically designed for use with three-dimensional APT data. Prior to this detailed characterisation work, the actual thermal impact from both heat treatment and quenching of small, lab-scale specimens was determined through correlation of both experimental results and calculations that modelled the heat transfer conditions using the lumped capacitance method. Subsequently, the maximum diffusion distance by random walk of the solute atoms was calculated for these periods, bearing significance on the propensity for these atoms to have the ability to cluster together, rather than segregate to the dislocation loops in the microstructure, which have a relatively larger interspacing distance. Age-hardening curves for the Al-1.1Cu-xMg (x = 0, 0.2, 0.5, 0.75, 1.0, 1.7 at.%) alloys at 150ºC show that the rapid hardening phenomenon (RHP) exists for Mg compositions ≥ 0.5Mg. Given that zone-like precipitate structures were unable to be detected by TEM or APT during the early stages of ageing at 150ºC, and that statistically significant dispersions of clusters were found in the APT data after ageing for 60 s, the RHP is attributed to these clustering reactions. Identification of clusters in the APT data has been achieved using the core-linkage algorithm and they have been found to be quite small, containing only a few atoms up to a couple of tens of atoms. The RHP is governed by some critical number density of both Mg clusters and Cu-Mg co-clusters of a critical size, whereas Cu clusters do not contribute significantly to the hardening mechanism. Significance testing indicates that Mg clusters are more significant at smaller clusters sizes and Cu-Mg co-clusters more important at larger cluster sizes. Hardness results also confirm the existence of rapid early hardening during secondary ageing at 65ºC in Al-1.1Cu-1.7Mg. The mechanism of secondary rapid hardening involves a combination of both secondary clustering from solute (mainly Mg atoms) residual in solution, and pre-existing amorphous primary clusters that have slower growth kinetics at the lower secondary ageing temperature. The latter occurs mainly by vacancy-assisted diffusion of Mg atoms as evidenced by the gradual increase of the Mg:Cu ratio of co-clusters. From an alloy design point of view it is important to fully understand the solute distribution in the microstructure to be able to subsequently optimise the configuration for enhanced material properties. The change in dispersion of solute atoms during ageing was determined by combining calculations of % vacancy-solute associations with detailed measurements of the dislocation loops to estimate the solute distribution within the microstructure. The implication of the balance of solute atoms segregated to the loops compared with that in the matrix is then discussed in the context of hardnening mechanisms.
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Remes, T. (Tiina). "Signs of radiation-induced accelerated ageing in survivors of childhood brain tumors:the incidence of cerebrovascular disease, neurocognitive impairment, secondary neoplasms, and low bone mineral density after 18 years of follow-up." Doctoral thesis, Oulun yliopisto, 2019. http://urn.fi/urn:isbn:9789526224305.

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Abstract Background: Childhood brain tumors (CBTs) are the most common solid tumors in childhood. CBT survivors have a high risk of several late-effects, including cerebrovascular disease (CVD), neurocognitive impairment, secondary neoplasms, and low bone mineral density; however, only a few studies have clinically investigated the late-sequelae in young-adult CBT survivors. Aim: To determine the prevalence of CVD, neurocognitive impairment, secondary neoplasms, and bone mineral density in a national cohort of radiotherapy-treated long-term survivors of CBT. Subjects and Methods: Radiotherapy-treated CBT survivors diagnosed between 1970–2008 were selected based on the following inclusion criteria: follow-up ≥5 years since the cessation of therapy and age of ≥16 years at the time of the study. Survivors were clinically and neuropsychologically examined, and investigated by magnetic resonance imaging (MRI), bone mineral densitometry, and laboratory analysis. Results: We included 74 survivors after a mean follow-up time of 18.9 ± 6.1 years. The mean age at follow-up was 28.4 ± 6.8 years and at diagnosis 8.3 ± 4.3 years. At the 20-year follow-up, the cumulative prevalence of CVD, along with small- and large-vessel disease was 52%, 38%, and 16%, respectively. Ischemic infarcts or transient ischemic attacks were diagnosed in 11% of the survivors, lacunar infarcts in 10%, and cerebral hemorrhage in 3%. White matter lesions (WMLs) were noted in 49% of the survivors. Higher blood pressure was associated with CVD, large-vessel disease, WMLs, and lacunar infarcts. Survivors had lower cognitive performance in all neuropsychological domains than controls. Mean verbal intelligence quotient was 89 ± 14 and mean performance intelligence quotient 87 ± 19. Executive functions (Z-score -5.0 ± 5.3 SD) and processing speed (Z-score -4.3 ± 5.4 SD) were extensively impaired. Executive functions and processing speed were associated with everyday life skills. Cumulative incidence of secondary meningiomas was 10.2% at the 25-year follow-up using the clinical data, and that of secondary neoplasms was 2.4% using the Finnish Cancer Registry data. We observed low bone mineral density in 23.6% of the survivors, which was associated with fractures in long bones. Conclusions: Young adult CBT survivors experienced late-consequences typically associated with ageing
Tiivistelmä Taustaa: Suomessa sairastuu vuosittain 46-60 lasta aivokasvaimeen, joka on lapsuusiän yleisin, kiinteä kasvain. Selviytyneillä on todettu lisääntynyt hoitojen myöhäisvaikutuksien riski. Kuitenkin nuorten aikuisten haittavaikutuksia on toistaiseksi tutkittu melko vähän. Tutkimuksen tarkoitus: Tarkoituksena oli selvittää sädehoidon jälkihaittoina esiintyvien sairauksien, kuten aivoverisuonisairauksien, älyllisten ongelmien, sekundaaristen kasvainten ja luustonhaurastumisen yleisyyttä ja riskitekijöitä suomalaisessa, kansallisessa kohortissa. Aineisto ja Menetelmät: Tutkimukseen kutsuttiin kaikki Suomessa lapsuusiällä aivokasvaimen sairastaneet aikuiset, jotka oli hoidettu sädehoidolla vuosina 1970-2008. Tutkittavat olivat yli 16-vuotiaita ja hoitojen päättymisestä oli yli 5 vuotta. Osallistuneille tehtiin kliininen ja neuropsykologinen tutkimus, pään magneettikuvaus, luustontiheysmittaus ja laboratoriotutkimuksia. Tulokset: Tutkimukseemme osallistui 74 nuorta aikuista 18,9 ± 6,1 vuotta hoitojen päättymisen jälkeen. Tutkittavat olivat iältään 28,4 ± 6,8 -vuotiaita osallistuessaan, ja 8,3 ± 4,3 -vuotiaita diagnoosihetkellä. Aivoverisuonisairaus todettiin 52% tutkimukseen osallistuneella 20 vuoden seurannan jälkeen, pienten suonten tauti oli 38 %:lla ja suurten suonten tauti 16 %:lla. Aivoinfarktin oli sairastanut 9 % tutkituista, lakuunainfarktin 10 % ja aivoverenvuodon 3 % tutkituista. Valkean aivoaineen muutoksia todettiin 49 %:lla magneettikuvauksessa. Korkea verenpaine lisäsi aivoverisuonisairauden, suurten suonten taudin, valkoisen aivoaineen muutoksien sekä lakuunainfarktien riskiä. Selviytyjien keskimääräinen kielellinen älykkyysosamäärä oli 89 ± 14 ja ei-kielellinen 87 ± 19. Suurimmat vaikeudet todettiin toiminnanohjauksessa (Z-luku -5,0 ± 5,3 SD) ja prosessointinopeudessa (Z-luku -4,3 ± 5,4 SD). Toiminnanohjauksen ja prosessointinopeuden vaikeudet olivat yhteydessä arkielämän haasteisiin. Sekundaaristen aivokalvokasvainten kumulatiivinen esiintyvyys oli 25 vuoden seuranta-aikana 10,2 % kliinisessä tutkimuksessa ja sekundaaristen kasvainten 2,4 % Syöpärekisteriaineistossa. Matala luustontiheys todettiin 23,6%:lla selviytyneistä. Johtopäätökset: Nuorilla aikuisilla, jotka ovat lapsena aivokasvaimen vuoksi saaneet sädehoitoa, esiintyy useita sellaisia jälkihaittoja, jotka yleensä liittyvät ikääntymiseen
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Jacumasso, Sheila Cristina. "CARACTERIZAÇÃO MICROESTRUTURAL DAS PARTÍCULAS DE SEGUNDA FASE DE UMA LIGA DE ALUMÍNIO AA7050 NAS CONDIÇÕES T7451, T6 E T6I4-65." UNIVERSIDADE ESTADUAL DE PONTA GROSSA, 2014. http://tede2.uepg.br/jspui/handle/prefix/1460.

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Made available in DSpace on 2017-07-21T20:43:44Z (GMT). No. of bitstreams: 1 Sheila Cristina Jacumasso.pdf: 3640428 bytes, checksum: 9f48682e159a5b7129a15abc7bb73945 (MD5) Previous issue date: 2014-06-02
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The AA7050 class from the 7XXX series alloys based on Al-Zn-Mg-Cu are widely used in aerospace structures and fuselage components, when the same are subjected to high stress loading due to its high ratio mechanical strength to density, in addition, to its corrosion resistance. The increased resistance of these alloys is obtained by heat treatment that involves solution treatment and ageing followed precipitation of a fine and homogeneous phase from the own chemical composition. In this, the present study aimed to perform the of AA7050 aluminum alloy microstructural characterization with different ageing heat treatment from the T7451, T6 and T6I4-65 conditions. Thus, different characterization techniques from the Optical Microscopy (OM), Scanning Electron Microscopy (SEM), Atomic Force Microscopy (AFM), Extraction of second phase particles, X-ray Diffraction (XRD) and Transmission Electron Microscopy (TEM) were used. It was evaluated which condition results is higher precipitation hardening phases that are responsible for the increased resistance of the alloy. The most significant results were obtained by TEM where it was possible to determine the morphology of the GPII zones in needles form with approximate size of 30nm and 10nm for both T6 and T6I4-65 conditions, respectively. Moreover, the metastable η' phase was identified in platelets form in the T7451, T6 and T6I4-65 conditions with approximate size of 50nm, 20nm and 10nm, respectively. The surface roughness analyses obtained by AFM have revealed that the T6I4-65 condition has higher surface roughness (Ra=14,87nm) when compared to the T7451 (Ra=7,65nm) and T6 (Ra=8,35nm) conditions. Indicating in this case, a higher density of small particles homogeneously distributed in the T6I4-65 aluminum alloy matrix.
As ligas da série 7XXX, da classe AA7050, à base de Al-Zn-Mg-Cu, são muito utilizadas na indústria aeroespacial, em estruturas de fuselagem e componentes sob alta tensão de carregamento, devido à sua alta relação entre resistência mecânica e densidade, além de sua resistência à corrosão. O aumento da resistência destas ligas é obtido por tratamento térmico de solubilização e envelhecimento, através da precipitação de uma fase fina e homogênea, proveniente da própria composição química. Neste contexto, o presente trabalho teve como objetivo principal realizar a caracterização microestrutural de uma liga de alumínio AA7050, submetida a diferentes tratamentos térmicos de envelhecimento nas condições T7451, T6 e T6I4-65. Desse modo, fez-se o uso de diferentes técnicas de caracterização entre elas Microscopia Ótica (MO), Microscopia Eletrônica de Varredura (MEV), Microscopia de Força Atômica (AFM), Extração de Partículas de segunda fase, Difração de Raios X (DRX) e Microscopia Eletrônica de Transmissão. Consequentemente, avaliou-se qual condição apresenta maior precipitação de fases endurecedoras que são responsáveis pelo aumento de resistência da liga. Os resultados mais significativos foram obtidos por MET onde foi possível determinar a morfologia das zonas GPII presentes na forma acicular (needles) com tamanho aproximado de 30nm na condição T6 e 10nm na condição T6I4-65. A fase metaestável η’ foi identificada na forma de plaquetas finas (platelets) nas condições T7451, T6 e T6I4-65 com tamanho aproximado de 50nm, 20nm e 10nm respectivamente. A rugosidade superficial obtida por AFM revelou que a condição T6I4-65 apresenta maior rugosidade superficial (Ra=14,87nm) quando comparado às condições T7451(Ra=7,65nm) e T6 (Ra=8,35nm), indicando maior densidade de partículas de pequena dimensão distribuída homogeneamente na matriz da liga de alumínio.
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Martinez, Jessica. "Exploring the Long-Term Impact of an Institutional Agent| Success of the Freedom Writers." Thesis, California State University, Long Beach, 2019. http://pqdtopen.proquest.com/#viewpdf?dispub=13425593.

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Demonstrated by this study, teachers as institutional agents can make a significant difference in the lives of their students during their educational endeavors and beyond. However, institutional agents remain rare within urban education, and adolescents’ access to these individuals in low-income communities is particularly low. This study used Stanton-Salazar’s theory of social capital and construct of institutional agents as a lens to understand the experiences of 14 individuals who participated in the Freedom Writers program. By giving a voice to students two decades after completing high school, this study conveys a critical perspective to the urban educational field. With there being a limited understanding of the lasting impact of such individuals on students as they transition onto adulthood participants’ personal accounts were explored to better understand their experiences.

As a qualitative study, this research inquired into the actions that guided the participants at the individual and situational level to having successful experiences. Data collection occurred through the utilization of an in-depth, semi-structured interviewing method, which provided rich data of the roles and functions of their high school teacher, Erin Gruwell, as an institutional agent. Additionally, providing data of their use of certain supports as provided by or made possible through Gruwell, four themes emerged from the findings of this study: (1) survival mode, (2) journey to Freedom Writers, (3) finding support, and (4) life after Freedom Writers. Within these themes, an in-depth exploration of the findings indicated the careful attention Gruwell placed in assessing the needs of students in order to provide the necessary supports as permitted by her social network and available resources, which involved access to additional institutional agents or other networks; significant forms of information; and other supportive forms of resources. The findings further indicated there being a critical impact to participants’ social development, and academic and career success. Through positive teacher-student relationships teachers can provide positive educational experiences that can have lifelong implications to empower students and create opportunities for life changes. Through the perspectives of the 14 participants, this study can influence the work of practitioners and policymakers in focusing on the needs and concerns of students attending urban high schools as well as in supporting teachers as institutional agents at the high school level.

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Tones, Megan Jane. "Patterns of engagement in workplace learning amongst employees from social sectors." Thesis, Queensland University of Technology, 2009. https://eprints.qut.edu.au/31248/1/Megan_Tones_Thesis.pdf.

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Continuous learning and development has become increasingly important in the information age. However, employees with limited formal education in lower status occupations may be disadvantaged in their opportunities for development, as their jobs tend to require more limited knowledge and skills. In mature age, such workers may be subject to cumulative disadvantage with respect to work related learning and development, as well as negative stereotyping. This thesis concerns work related learning and development from a lifespan development psychology perspective. Development across the lifespan is grounded in biocultural co-constructivism. That is, the reciprocal influences of the individual and environment produce change in the individual. Existing theories and models of adaptive development attempt to explain how developmental resources are allocated across the lifespan. These included the Meta- theory of Selective Optimisation with Compensation, Dual Process Model of Self Regulation, and Developmental Regulation via Optimisation and Primary and Secondary Control. These models were integrated to create the Model of Adaptive Development for Work Related Learning. The Learning and Development Survey (LDS) was constructed to measure the hypothesised processes of adaptive development for work related learning, which were individual goal selection, individual goal engagement, individual goal disengagement, organisational opportunities (selection and engagement), and organisational constraints. Data collection was undertaken in two phases: the pilot study and the main study. The objective of the pilot study was to test the LDS on a target population of 112 employees from a local government organisation. Exploratory factor analysis reduced the pilot version of the survey to 38 items encompassing eight constructs which covered the processes of the model of adaptive development for work related learning. In the main study, the Revised Learning and Development Survey (R-LDS) was administered to another group of 137 employees from the local government organisation, as well as 110 employees from a private healthcare organisation. The purpose of the main study was to validate the R-LDS on two different groups to provide evidence of stability, and compare survey scores according to age and occupational status to determine construct validity. Findings from the main study indicated that only four constructs of the R-LDS were stable, which were organisational opportunities – selection, individual goal engagement, organisational constraints – disengagement and organisational opportunities – engagement. In addition, MANOVA studies revealed that the demographic variables affected organisational opportunities and constraints in the workplace, although individual goal engagement was not influenced by age. The findings from the pilot and main study partially supported the model of adaptive development for work related learning. Given that only four factors displayed adequate reliability in terms of internal consistency and stability, the findings suggest that individual goal selection and individual goal disengagement are less relevant to work related learning and development. Some recent research which emerged during the course of the current study has suggested that individual goal selection and individual goal disengagement are more relevant when goal achievement is impeded by biological constraints such as ageing. However, correlations between the retained factors support the model of adaptive development for work related learning, and represent the role of biocultural co-constructivism in development. Individual goal engagement was positively correlated with both opportunity factors (selection and engagement), while organisational constraints – disengagement was negatively correlated with organisational opportunities – selection. Demographic findings indicated that higher occupational status was associated with more opportunities for development. Age was associated with fewer opportunities or greater constraints for development, especially for lower status workers.
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Sivan, Atara. "Attitudes of secondary school students and teachers towards the aim of school as a socialising agent for leisure /." Thesis, [Hong Kong : University of Hong Kong], 1990. http://sunzi.lib.hku.hk/hkuto/record.jsp?B13009515.

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Dussart, François Mathieu Didier. "Genomic analysis of secondary metabolism in Ramularia collo-cygni, causative agent of Ramularia leaf spot disease of barley." Thesis, University of Edinburgh, 2017. http://hdl.handle.net/1842/28829.

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In the past two decades a new barley threat has emerged as the disease Ramularia leaf spot (RLS) became more prevalent in temperate regions worldwide. This disease, first identified in the late 19th century, is caused by the filamentous fungus Ramularia collo-cygni (Rcc) and can cause substantial yield losses as well as reduce grain quality. RLS typically occurs late in the growing season and characteristic disease symptoms are usually seen after the crop has flowered. Expression of RLS lesions is thought to be associated with the action of fungal secondary metabolism products. The one group of secondary metabolites (SMs) characterised to date from Rcc, the anthraquinone toxins rubellins, are known to cause necrosis to plant tissues in a non-host specific manner. Therefore, it appears that fungal secondary metabolism might be a key component in understanding the interaction between Rcc and its host. In this study, more than 23 core genes involved in the biosynthesis of SMs belonging to the polyketide and non-ribosomal peptide pathways were identified in the genome of Rcc. Putative clusters containing genes with a predicted function relating to secondary metabolism were identified by in silico genome walking in the genetic loci adjacent to Rcc SM core genes. Two gene clusters containing no SM core gene were also identified. Five of the putative SM clusters exhibited similarity to the known fungal SM biochemical pathways involved in gliotoxin, monodictyphenone, ferricrocin, betaenone and chaetoglobosins biosynthesis. Several gene clusters exhibited similarity to SM clusters from fungal species where the SM pathway is uncharacterised. Changes in transcript abundance of selected SM core genes during RLS development in artificially inoculated barley seedlings were tested. Transcript levels were found to be the highest at an early stage of disease development, typically during the asymptomatic and early lesions formation stages and declined over time, suggesting that the associated SMs in Rcc, may not necessarily be involved in symptoms appearance. The in planta mode of action of the non-host specific photoactivated toxin rubellin D was studied in the model plant Arabidopsis thaliana. Rubellin-induced cell death appeared phenotypically reminiscent of programmed cell death (PCD). Full expression of rubellin D-induced cell death required the host salicylic acid (SA) pathway and the host proteasome supporting the PCD response to this fungal SM. However, a clear correlation between toxin sensitivity and disease susceptibility could not be found, suggesting a potential alternative role for rubellin in disease symptom development.
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Books on the topic "Secondary ageing"

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Kudrnáčová, Naděžda. Caused motion: Secondary agent constructions. Brno: Masarykova univerzita, 2013.

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National Academies Press (U.S.), ed. Review of chemical agent secondary waste disposal and regulatory requirements. Washington, D.C: National Academies Press, 2007.

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J, Allebon, ed. Action research in the secondary school: The psychologist as change agent. London: Routledge, 1988.

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National Research Council (U.S.). Committee to Review Secondary Waste Disposal and Regulatory Requirements for the Assembled Chemical Weapons Alternatives Program. Review of secondary waste disposal planning for the Blue Grass and Pueblo Chemical Agent Destruction Pilot Plants. Washington, D.C: National Academies Press, 2008.

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National Research Council (U.S.). Committee to Review Secondary Waste Disposal and Regulatory Requirements for the Assembled Chemical Weapons Alternatives Program. Review of secondary waste disposal planning for the Blue Grass and Pueblo Chemical Agent Destruction Pilot Plants. Washington, D.C: National Academies Press, 2008.

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National Research Council (U.S.). Committee to Review Secondary Waste Disposal and Regulatory Requirements for the Assembled Chemical Weapons Alternatives Program. Review of secondary waste disposal planning for the Blue Grass and Pueblo Chemical Agent Destruction Pilot Plants. Washington, D.C: National Academies Press, 2008.

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National Research Council (U.S.). Committee to Review Secondary Waste Disposal and Regulatory Requirements for the Assembled Chemical Weapons Alternatives Program. Review of secondary waste disposal planning for the Blue Grass and Pueblo Chemical Agent Destruction Pilot Plants. Washington, D.C: National Academies Press, 2008.

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Bowker, Lesley K., James D. Price, Ku Shah, and Sarah C. Smith. Cardiovascular. Oxford University Press, 2018. http://dx.doi.org/10.1093/med/9780198738381.003.0010.

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This chapter provides information on the ageing cardiovascular system, chest pain, stable angina, acute coronary syndromes, myocardial infarction, hypertension, treatment of hypertension, presentation of arrhythmias, management of arrhythmias, atrial fibrillation, rate/rhythm control in atrial fibrillation, stroke prevention in atrial fibrillation, bradycardia and conduction disorders, common arrhythmias and conduction abnormalities, heart failure assessment, acute heart failure, chronic heart failure, dilemmas in heart failure, heart failure with preserved left ventricular function, valvular heart disease, peripheral oedema, preventing venous thromboembolism in an older person, peripheral vascular disease, gangrene in peripheral vascular disease, and vascular secondary prevention.
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Committee on Review of Chemical Agent Secondary Waste Disposal and Regulatory Requirements, Board on Army Science and Technology, National Research Council, and Division on Engineering and Physical Sciences. Review of Chemical Agent Secondary Waste Disposal and Regulatory Requirements. National Academies Press, 2007.

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Review of Chemical Agent Secondary Waste Disposal and Regulatory Requirements. Washington, D.C.: National Academies Press, 2007. http://dx.doi.org/10.17226/11881.

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Book chapters on the topic "Secondary ageing"

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Bueno, Valquiria. "Age-Related Changes in Primary and Secondary Lymphoid Organs." In Healthy Ageing and Longevity, 13–22. Cham: Springer International Publishing, 2021. http://dx.doi.org/10.1007/978-3-030-87532-9_2.

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Maury, Nicolas, Benoît Denand, Moukrane Dehmas, Elisabeth Aeby-Gautier, Benoît Appolaire, Claude Archambeau-Mrguet, Jérôme Delfosse, and Philippe Emile. "Formation of Secondary α Phase During Ageing in Ti17 Alloy." In Proceedings of the 13th World Conference on Titanium, 449–54. Hoboken, NJ, USA: John Wiley & Sons, Inc., 2016. http://dx.doi.org/10.1002/9781119296126.ch70.

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Wang, Haifeng. "Multi-Agent Coordination for Secondary Voltage Control." In Autonomous Systems and Intelligent Agents in Power System Control and Operation, 205–27. Berlin, Heidelberg: Springer Berlin Heidelberg, 2003. http://dx.doi.org/10.1007/978-3-662-05955-5_10.

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Bulte, J. W. M., M. W. A. Jonge, R. L. Kamman, F. Zuiderveen, T. H. The, L. Leij, and K. G. Go. "Magnetite as a Potent Contrast-Enhancing Agent in Magnetic Resonance Imaging to Visualize Blood-Brain Barrier Disruption." In Mechanisms of Secondary Brain Damage, 30–34. Vienna: Springer Vienna, 1993. http://dx.doi.org/10.1007/978-3-7091-9266-5_4.

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Armano, Giuliano, Gianmaria Mancosu, Alessandro Orro, and Eloisa Vargiu. "A Multi-agent System for Protein Secondary Structure Prediction." In Lecture Notes in Computer Science, 14–32. Berlin, Heidelberg: Springer Berlin Heidelberg, 2005. http://dx.doi.org/10.1007/11599128_2.

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Marchal, Fabrice, and Kai Nagel. "Computation of Location Choice of Secondary Activities in Transportation Todels with Cooperative Agents." In Applications of Agent Technology in Traffic and Transportation, 153–64. Basel: Birkhäuser Basel, 2005. http://dx.doi.org/10.1007/3-7643-7363-6_10.

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Alaghband, Marie, and Ivan Garibay. "Effects of Non-cognitive Factors on Post-Secondary Persistence of Deaf Students: An Agent-Based Modeling Approach." In Proceedings of the 2020 Conference of The Computational Social Science Society of the Americas, 1–13. Cham: Springer International Publishing, 2021. http://dx.doi.org/10.1007/978-3-030-83418-0_1.

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Pachana, Nancy A. "3. The psychology of ageing." In Ageing: A Very Short Introduction, 45–65. Oxford University Press, 2016. http://dx.doi.org/10.1093/actrade/9780198725329.003.0003.

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Psychological theories of ageing encompass mental health and emotional well-being as well as changes in these states, at individual as well as interpersonal levels, associated with increasing age. ‘The psychology of ageing’ reviews different ways of studying changes in functioning: cross-sectional, longitudinal, and sequential study designs; the varying psychological theories of ageing, including the disengagement theory, activity theory, continuity theory, socioemotional selectivity theory, convoy theory, and social identity theory; and the cognitive aspects of ageing, including changes in thinking and behaviour as a result of both primary and secondary ageing. It also considers how personality and emotions are expressed in later life and the treatment of mental disorders.
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Mariotti, Stefano. "Ageing and thyroid disease." In Oxford Textbook of Endocrinology and Diabetes, 1519–26. Oxford University Press, 2011. http://dx.doi.org/10.1093/med/9780199235292.003.0138.

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The relationship between ageing and the thyroid has been the object of intensive investigation (1) for several pathophysiological, epidemiological, and clinical reasons. Symptoms of ageing can easily be confused with hypothyroidism, and decreased thyroid function was once believed to be a hallmark of senescence. Thyroid diseases are common in the elderly, but their clinical manifestations are different from those seen in younger patients, being more vague, subtle, and often hidden by concurrent diseases. The interpretation of thyroid function tests is often difficult in elderly individuals, due to age-associated changes of thyroid physiology, alterations of thyroid function tests secondary to nonthyroidal illness, and/or drug intake. Treatment of thyroid disease deserves special attention in elderly patients due to the increased risk of complications and/or drug interactions. If untreated, thyroid dysfunctions may lead to significant morbidity in elderly people, mostly through an aggravation of coexistent cardiovascular disease. A remarkable exception to this concept is represented by mild hypothyroidism, which in the oldest elderly population appears to be associated with no harm, and possibly increased survival.
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Pachana, Nancy A. "2. Physical and biological aspects of ageing." In Ageing: A Very Short Introduction, 22–44. Oxford University Press, 2016. http://dx.doi.org/10.1093/actrade/9780198725329.003.0002.

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‘Physical and biological aspects of ageing’ considers influences on longevity and the physical disorders commonly experienced at the end of life. It describes primary and secondary ageing and different biological theories of ageing—error and programme theories. Error theories (e.g. wear and tear theory, free radical theory, and somatic DNA damage theory) postulate that ageing and death are the result of environmental damage to the body over time. Programme theories (e.g. endocrine theory, immunological theory, and genetic theory (programmed longevity)) postulate that lifelong growth and development is genetically programmed to follow a pre-determined timeline. The ageing brain and body, and disease trajectories later in life are also considered.
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Conference papers on the topic "Secondary ageing"

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Renato, F. S., Felipe V. Lopes, and Raphael L. A. Reis. "The influence of CCVT ageing on secondary voltage compensation." In 2018 Simposio Brasileiro de Sistemas Eletricos (SBSE) [VII Brazilian Electrical Systems Symposium (SBSE)]. IEEE, 2018. http://dx.doi.org/10.1109/sbse.2018.8395647.

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Kim, Hyungkyoo, Hoansung Jung, Incheol Lim, Yeonggarp Cho, Jeongsoo Ryu, and Youngchul Park. "Ageing Management Status of HANARO Research Reactor." In 17th International Conference on Nuclear Engineering. ASMEDC, 2009. http://dx.doi.org/10.1115/icone17-75126.

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Ageing means time-dependent changes of the quality and design characteristics having existed at the time of an approval, and ageing may occur during the operating time of a facility. The management of equipment begins with an awareness that ageing is not about how old the equipment is, but is about what is known about its condition, and the factors that influence the onset, evolution and mitigation of its degradation. HANARO, the open-tank-in-pool type research reactor with 30MW thermal power, achieved its first criticality in 1995. The reactor power has been gradually increased to the full power reached in June 2004. Many activities for an ageing management including improvement of the reactor systems were conducted during 13 years. The in-service inspection plans, for the reactor structure and the safety related piping designed as ASME safety category III, were established and carried out. The preventive maintenance for the primary cooling system including the pumps and heat exchangers, the electric system was also performed. The safety diagnosis and reinforcement for an effective life management and insurance of the safety of the building structures such as the reactor building, stack, secondary cooling system equipment room and cooling tower in HANARO were performed. The upgrade of the instrumentation and control system has been carried out gradually since 2001. This paper describes the conducted ageing management activities and long term ageing management plan of HANARO.
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Caouette, Christiane, Martin N. Bureau, and L’Hocine Yahia. "Secondary Stability of a Composite Biomimetic Cementless Hip Stem." In ASME 2008 Summer Bioengineering Conference. American Society of Mechanical Engineers, 2008. http://dx.doi.org/10.1115/sbc2008-192176.

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Total hip replacement is one of the most successful and frequent surgery in the world; over a million of these procedures are performed every year, and the numbers are growing with the ageing of the general population. The patients who receive these implants also are younger nowadays. Major problems however still subsist with traditional hip stems: aseptic loosening is a common cause of revision surgery. The main causes of aseptic loosening are both mechanical and biological in origin. Mechanical causes include stress shielding and micromotions at bone-implant interface, and biological causes are mainly osteolysis triggered by wear debris formation and bone remodeling. To remedy the mechanical issues, a biomimetic concept was developed (patent pending): an osseointegrated stem with mechanical properties close to those of the surrounding bone would avoid both stress shielding and micromotions phenomena. To evaluate this concept, a finite element model (FEM) was developed and used to simulate bone resorption, stress shielding and micromotions [1]. The preliminary results were promising as those problems were significantly reduced with the new prosthesis, but the model still remained to be proved accurate; its bone-implant interface was of particular interest because of its decisive influence on micromotions.
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Bonneux, Cindel, Deeman Yousif Mahmood, Martijn Scherrenberg, Maarten Falter, Gustavo Rovelo Ruiz, Hanne Kindermans, Dominique Hansen, Reijo Laaksonen, Paul Dendale, and Karin Coninx. "The CoroPrevention-SDM Approach: A Technology-supported Shared Decision Making Approach for a Comprehensive Secondary Prevention Program for Cardiac Patients." In 8th International Conference on Information and Communication Technologies for Ageing Well and e-Health. SCITEPRESS - Science and Technology Publications, 2022. http://dx.doi.org/10.5220/0011042300003188.

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Kudins, Janis. "Determinants of the Elderly Employment in Latvia." In 22nd International Scientific Conference. “Economic Science for Rural Development 2021”. Latvia University of Life Sciences and Technologies. Faculty of Economics and Social Development, 2021. http://dx.doi.org/10.22616/esrd.2021.55.032.

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In Latvia, from 2011 to 2020 the number of people 65+ increased by 2.7 %, but the number of the employed people 65+ increased by 94.4 %. The aim of this research is to identify the determinants of the elderly employment in the context of active ageing. The author analysed secondary data collected by the international and Latvia’s institutions as well as by Latvia’s researchers who have studied the elderly. The results of these studies and the data of Latvia’s statistics show that the rapid growth of the elderly employment in Latvia is more likely not an indicator of active ageing, but the elderly’s attempt to overcome poverty. 60.3 % of the elderly in Latvia continue to work in order to increase their current income, and only 10.2 % – for non-financial reasons, which is one of the lowest values in the EU. The gap between the average income of Latvia’s population and the income of people 65+ is increasing over the past 10 years. The elderly in Latvia work mainly in education and health care. These sectors have relatively lower average wages and are therefore less attractive to young people, so the elderly employment in them shows not only the importance of knowledge and experience, but also the difficulties in attracting new employees. The author concludes that Latvia is still far from real active ageing, which is typical for the most competitive EU countries. In order to move in this direction, it would be useful to use the experience of the EU’s active ageing initiatives.
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Leenaers, A., M. Verwerft, D. Boulanger, N. Itagaki, and T. Matsumura. "Microstructure of Spent MOX Fuel Stored Under Dry Air for 25 Years." In ASME 2001 8th International Conference on Radioactive Waste Management and Environmental Remediation. American Society of Mechanical Engineers, 2001. http://dx.doi.org/10.1115/icem2001-1194.

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Abstract In this paper, some results of microstructure analyses on spent MOX fuel with burnup of about 20 GWd/tM, stored for an extended period, are presented. The samples are taken from fuel that has been stored for 25 years either in intact cladding or exposed to dry air. The results of this investigation are compared to the microstructure observations made in the post-irradiation campaign, conducted on the same or sibling fuel rods shortly after reactor unloading (i.e. about twenty years ago). The fuel from the long term stored intact rods demonstrated an identical behaviour, compared to its state shortly after reactor unloading. Segments of fuel rods that were exposed to dry air showed an alteration of the grain boundary cohesion of the UO2 grains, while apparently the Pu-rich zones were unaffected. These findings are coherent with the results found in accelerated ageing experiments. On the other hand, the formation of secondary phases with higher oxidation states of uranium, often observed during accelerated ageing experiments, could not be confirmed here.
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Nicak, Tomas. "Ductile Tearing Simulations to Support Design of Large Scale Tests on Ferritic Pipes to Be Performed in the European Project ATLAS+." In ASME 2019 Pressure Vessels & Piping Conference. American Society of Mechanical Engineers, 2019. http://dx.doi.org/10.1115/pvp2019-93569.

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Abstract The safety and reliability of all systems has to be maintained throughout the lifetime of a nuclear power plant (NPP). This requires a systematic ageing management procedure for justifying their safe long term operation. One fundamental part in this process is to demonstrate the integrity of the nuclear power plant components. The European project ATLAS+ aims to develop and validate advanced methods of structural integrity assessment applicable in the ageing and lifetime management of primary and secondary circuit components. To support development and validation of those methods, a large scale test program was developed with the aim to investigate fracture behavior of relevant piping material at the component level. Three of planned large scale experiments focus on the fracture behavior of ferritic piping made of material WB 36 (15 NiCuMoNb 5), that is representative of secondary feedwater lines installed in German NPPs. In order to verify design calculations conducted by means of the classical fracture mechanics approach based on J-Integral [1], detailed local approach analyses are performed for three mock-ups with different initial defects. The local approach analyses presented in this paper are based on the local micromechanical model proposed by Gurson and further modified by Tvergaard. Calibration of required material parameters and prediction of the mock-up behavior during the test is discussed. In order to support constraint investigations stress triaxiality ahead of the crack front during crack propagation in the mock-ups is evaluated and compared to the stress triaxiality in CT20 and SENT specimens. As high stress triaxiality generally limits plastic deformation and increases the crack tip constraint, it is a good parameter to look at if constraint effects are considered.
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Nicak, Tomas, and Alexey Rempel. "Post-Test Analysis of a Large Scale Mock-Up Test Performed in the European Project ATLAS+." In ASME 2021 Pressure Vessels & Piping Conference. American Society of Mechanical Engineers, 2021. http://dx.doi.org/10.1115/pvp2021-60495.

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Abstract The safety and reliability of all systems has to be maintained throughout the lifetime of a nuclear power plant (NPP). This requires a systematic ageing management procedure for justifying their safe long term operation. One fundamental part in this process is to demonstrate the integrity of the nuclear power plant components. The European project ATLAS+ aims to develop and validate advanced methods of structural integrity assessment applicable in the ageing and lifetime management of primary circuit components. To support development and validation of those methods a large scale test programme was developed with the aim to investigate fracture behavior of relevant piping material at the component level. Three of the planned large scale experiments focus on the fracture behavior of flawed ferritic pipe segments made of material WB 36 (15 NiCuMoNb 5); this material is representative of secondary feedwater lines installed in German NPPs. In order to improve understanding of test results post-test simulations and fractographic examination of all large scale tests are planned, some of them have been already performed. In this paper the post-test simulation of the mock-up FP2 (ferritic pipe with outer semi-elliptical circumferential crack) is presented and discussed. This mock-up was selected because it experienced an unexpected brittle fracture during the test, which occurred after limited ductile crack propagation. To investigate both the ductile and the brittle crack propagation phases of the test detailed ductile tearing analysis and brittle fracture assessment have been performed. In addition, relevant results of fractographic examination of the mock-up FP2 are presented and discussed.
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Hasselqvist, Magnus. "Viscoplastic Modelling for Industrial Gas Turbine (IGT) Application With Emphasis on the Sheet Material Haynes 230." In ASME Turbo Expo 2002: Power for Land, Sea, and Air. ASMEDC, 2002. http://dx.doi.org/10.1115/gt2002-30659.

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The need for high quality simulation to support cyclic life estimation of IGT hot parts is obvious. With increasing computational resources it is now feasible to perform fully 3D simulations using viscoplastic models. The superalloy Haynes 230 has been analyzed and modelled to support design against excessive deformation and Thermo Mechanical Fatigue (TMF). This requires a model which can accurately predict the stress corresponding to 1% creep after 40000h and the inelastic strain range in the stabilized loop. The one most important aspect of the modelling was identified as ‘how to predict the low temperature yield strength in the stabilized loop’, i.e. after TMF cycling with long holding times at service temperature. Haynes 230 is delivered in an unstable solutioned state and precipitates secondary carbides in service. The resulting carbide morphology, and therefore the mechanical properties, depends on the strain range and the service temperature. The dense distribution of fine carbides after cycling at 600°C, and the corresponding very high cyclic hardening, indicates that TMF cycling with a service temperature of 600 °C results in a corresponding increase in the low temperature yield strength. If the service temperature is high, over ageing will occur and the low temperature yield strength will decrease instead. This has been taken into account in a novel ‘crude but useful’ model containing a stabilized yield strength which depends explicitly on the service temperature. The modelling has been backed by case specific testing and SEM/TEM studies. The model has been implemented in ABAQUS and is being used. Further analysis will refine the model through improved understanding of the precipitation and ageing process, and also extend it to similar materials such as Hastelloy-X, 800H, 253MA and Haynes HR-120.
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Walsh, Peter W., Craig McLachlan, Leigh Ladd, and R. Mark Gillies. "Novel Extra Aortic Counterpulsation Device for Enhancing Cardiac Performance." In ASME 2011 Summer Bioengineering Conference. American Society of Mechanical Engineers, 2011. http://dx.doi.org/10.1115/sbc2011-53699.

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Heart failure is the fastest growing cardiovascular disorder. Incidence is rising at a rate of approximately 2% to 5% in people over 65 years of age, and 10% in people over 75 years of age [1]. Over 13 Million people suffer from heart failure in the USA, Europe, Canada and Australia, and heart failure is a leading cause of hospital admissions and re-admissions in Americans older than 65 years of age [2]. The secondary heart pump system is the expansion and recoil of the aorta which reduces heart load and drives left coronary artery blood flow. Increases in aortic stiffness are a result of elastin degradation due to ageing and/or cardiovascular diseases such as atherosclerosis [3–5], which increase heart load and pulse pressure [6–10]. Significantly higher aortic stiffness is found in hypertensive and heart failure suffers [6,7,9–11]. Specifically, healthy aged subjects have been found to have aortic stiffness 50% higher relative to subjects in a young and healthy group, while symptomatic hypertensive patients in heart failure have aortic stiffness further increased by approx. 77% relative to the age matched healthy cohort (i.e. by ∼88% relative to the young and healthy group) [11].
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Reports on the topic "Secondary ageing"

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Werny, Rafaela, Marie Reich, Miranda Leontowitsch, and Frank Oswald. EQualCare Policy Report Germany : Alone but connected? Digital (in)equalities in care work and generational relationships among older people living alone. Frankfurter Forum für interdisziplinäre Alternsforschung, Goethe-Universität Frankfurt am Main, October 2022. http://dx.doi.org/10.21248/gups.69905.

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The policy review is part of the project EQualCare: Alone but connected? Digital (in)equalities in care work and generational relationships among older people living alone, a three-year international project involving four countries: Finland, Germany, Latvia and Sweden. EQualCare interrogates inequalities by gender, cultural and socio-economic background between countries, with their different demographics and policy backgrounds. As a first step into empirical analysis, the policy review aims to set the stage for a better understanding of, and policy development on, the intersections of digitalisation with intergenerational care work and care relationships of older people living alone in Germany. The policy review follows a critical approach, in which the problems policy documents address are not considered objective entities, but rather discursively produced knowledge that renders visible some parts of the problem which is to be solved as other possible perspectives are simultaneously excluded. Twenty publicly available documents were studied to analyse the processes in which definitions of care work and digital (in)equalities are circulated, translated and negotiated between the different levels of national government, regional governments and municipalities as well as other agencies in Germany. The policy review consists of two parts: a background chapter providing information on the social structure of Germany, including the historical development of Germany after the Second World War, its political structure, information on the demographic situation with a focus on the 60+ age group, and the income of this age group. In addition, the background presents the structure of work and welfare, the organisation of care for old people, and the state of digitalisation in Germany. The analysis chapter includes a description of the method used as well as an overview of the documents chosen and analysed. The focus of this chapter is on the analysis of official documents that deal with the interplay of living alone in old age, care, and digitalisation. The analysis identified four themes: firstly, ageing is framed largely as a challenge to society, whereas digitalisation is framed as a potential way to tackle social challenges, such as an ageing society. Secondly, challenges of ageing, such as need of care, are set at the individual level, requiring people to organise their care within their own families and immediate social networks, with state support following a principle of subsidiarity. Thirdly, voluntary peer support provides the basis for addressing digital support needs and strategies. Publications by lobby organisations highlight the important work done by voluntary peer support for digital training and the benefits this approach has; they also draw attention to the over-reliance on this form of unpaid support and call for an increase in professional support in ensuring all older people are supported in digital life. Fourthly, ageing as a hinderance to participation in digital life is seen as an interim challenge among younger old people already online.
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Horwitz, Benjamin, and Barbara Gillian Turgeon. Secondary Metabolites, Stress, and Signaling: Roles and Regulation of Peptides Produced by Non-ribosomal Peptide Synthetases. United States Department of Agriculture, 2005. http://dx.doi.org/10.32747/2005.7696522.bard.

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Fungal pathogens of plants produce a diverse array of small molecules. Often referred to as secondary metabolites because they were thought to be dispensable for basic functions, they may indeed have central roles as signals for the fungal cell, and in interactions with the host. We have identified more than a dozen genes encoding nonribosomal peptide synthetases (NPS) in Cochliobolusheterostrophus, the agent of southern corn leaf blight. The aim of this project was to identify roles of these genes in stress responses and signaling. The first objective was to test a complete collection of C. heterostrophus nonribosomal peptide synthetase (NRPS)-encoding gene deletion mutant and wildtype (WT) strains for sensitivity to various agents of oxidative (ROS) and nitrosative (RNOS) stress, in vitro. The second objective and next step in this part of the project was to study the relevance of sensitivity to ROS and RNOS in the host pathogen interaction, by measuring the production of ROS and RNOS in planta, when plants are inoculated with wild type and mutant strains. A third objective was to study expression of any genes shown to be involved in sensitivity to ROS or RNOS, in vitro and in planta. Another objective was to determine if any of the genes involved in oxidative or nitrosative stress responses are regulated by components of signal transduction pathways (STP) that we have identified and to determine where mechanisms overlap. Study of the collection of nps mutants identified phenotypes relevant for virulence, development and oxidative stress resistance for two of the genes, NPS2 and NPS6. Mutants in genes related to RNOS stress have no virulence phenotypes, while some of those related to ROS stress have reduced virulence as well as developmental phenotypes, so we focused primarily on ROS stress pathways. Furthermore, the identification of NPS2 and NPS6 as encoding for NRPS responsible for siderophore biosynthesis lent a new focus to the project, regulation by Fe. We have not yet developed good methods to image ROS in planta and work in this direction is continuing. We found that NPS6 expression is repressed by Fe, responding over the physiological Fe concentration range. Studying our collection of mutants, we found that conserved MAPK and G protein signal transduction pathways are dispensable for Fe regulation of NPS6, and initiated work to identify other pathways. The transcription factor SreA is one candidate, and is responsible for part, but not all, of the control of NPS6 expression. The results of this project show that the pathogen contends with oxidative stress through several signaling pathways. Loss of the siderophore produced by Nps6 makes the fungus sensitive to oxidative stress, and decreases virulence, suggesting a central role of the ability to sequester and take up extracellular iron in the host-pathogen interaction. Siderophores, and manipulation of Fe levels, could be targets for new strategies to deal with fungal pathogens of maize and other plants.
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Sionov, Edward, Nancy Keller, and Shiri Barad-Kotler. Mechanisms governing the global regulation of mycotoxin production and pathogenicity by Penicillium expansum in postharvest fruits. United States Department of Agriculture, January 2017. http://dx.doi.org/10.32747/2017.7604292.bard.

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The original objectives of the study, as defined in the approved proposal, are: To characterize the relationship of CreA and LaeA in regulation of P T production To understand how PacC modulates P. expansumpathogenicity on apples To examine if other secondary metabolites are involved in virulence or P. expansumfitness To identify the signaling pathways leading to PAT synthesis Penicilliumexpansum, the causal agent of blue mould rot, is a critical health concern because of the production of the mycotoxinpatulin (PAT) in colonized apple fruit tissue. Although PAT is produced by many Penicilliumspecies, the factors activating its biosynthesis were not clear. This research focused on host and fungal mechanisms of activation of LaeA (the global regulator of secondary metabolism), PacC (the global pH modulator) and CreA (the global carbon catabolite regulator) on PAT synthesis with intention to establish P. expansumas the model system for understanding mycotoxin synthesis in fruits. The overall goal of this proposal is to identify critical host and pathogen factors that mechanistically modulate P. expansumgenes and pathways to control activation of PAT production and virulence in host. Several fungal factors have been correlated with disease development in apples, including the production of PAT, acidification of apple tissue by the fungus, sugar content and the global regulator of secondary metabolism and development, LaeA. An increase in sucrose molarity in the culture medium from 15 to 175 mM negatively regulated laeAexpression and PAT accumulation, but, conversely, increased creAexpression, leading to the hypothesis that CreA could be involved in P. expansumPAT biosynthesis and virulence, possibly through the negative regulation of LaeA. We found evidence for CreAtranscriptional regulation of laeA, but this was not correlated with PAT production either in vitro or in vivo, thus suggesting that CreA regulation of PAT is independent of LaeA. Our finding that sucrose, a key ingredient of apple fruit, regulates PAT synthesis, probably through suppression of laeAexpression, suggests a potential interaction between CreA and LaeA, which may offer control therapies for future study. We have also identified that in addition to PAT gene cluster, CreA regulates other secondary metabolite clusters, including citrinin, andrastin, roquefortine and communesins, during pathogenesis or during normal fungal growth. Following creation of P. expansumpacCknockout strain, we investigated the involvement of the global pH regulator PacC in fungal pathogenicity. We demonstrated that disruption of the pH signaling transcription factor PacC significantly decreased the virulence of P. expansumon deciduous fruits. This phenotype is associated with an impairment in fungal growth, decreased accumulation of gluconic acid and reduced synthesis of pectolytic enzymes. We showed that glucose oxidase- encoding gene, which is essential for gluconic acid production and acidification during fruit colonization, was significantly down regulated in the ΔPepacCmutant, suggesting that gox is PacC- responsive gene. We have provided evidence that deletion of goxgene in P. expansumled to a reduction in virulence toward apple fruits, further indicating that GOX is a virulence factor of P. expansum, and its expression is regulated by PacC. It is also clear from the present data that PacC in P. expansumis a key factor for the biosynthesis of secondary metabolites, such as PAT. On the basis of RNA-sequencing (RNA-seq) analysis and physiological experimentation, the P. expansumΔlaeA, ΔcreAand ΔpacCmutants were unable to successfully colonize apples for a multitude of potential mechanisms including, on the pathogen side, a decreased ability to produce proteolytic enzymes and to acidify the environment and impaired carbon/nitrogen metabolism and, on the host side, an increase in the oxidative defence pathways. Our study defines these global regulatory factors and their downstream signalling pathways as promising targets for the development of strategies to fight against this post-harvest pathogen.
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4

Konstantinou, Theodora, Donghui Chen, Konstantinos Flaris, Kyubyung Kang, Dan Daehyun Koo, Jonathon Sinton, Konstantina Gkritza, and Samuel Labi. A Strategic Assessment of Needs and Opportunities for the Wider Adoption of Electric Vehicles in Indiana. Purdue University, 2022. http://dx.doi.org/10.5703/1288284317376.

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The primary objective of this study was to assess the challenges and opportunities associated with the provision of appropriate infrastructure to support electric vehicle (EV) operations and electrification across Indiana. A secondary objective of this study was to develop a strategic plan for INDOT that outlines new business opportunities for developing EV charging stations. To achieve these objectives, the project team assessed current and emerging trends in EV operations, particularly EV charging infrastructure and EV demand forecasting. They also examined opportunities for the strategic deployment of EV charging stations by identifying EV infrastructure deficit areas; investigated the impact of EV adoption on highway revenue and the feasibility of new revenue structures; and evaluated strategic partnerships and business models. The agent-based simulation model developed for future long distance EV trip scenarios enables INDOT to identify EV energy deficient areas for current and future energy charging demand scenarios, and it can support Indiana’s strategic plans for EV charging infrastructure development. The results of the revenue impact analysis can inform INDOT’s revenue model. The estimations of the recovery EV fee, the VMT fee, and pay-as-you-charge fee that break-even the fuel tax revenue loss can be used by INDOT in pilot programs to capture users’ perspectives and estimate appropriate fee rates and structures. The insights obtained from the stakeholder interviews can be used to enhance preparedness for increasing EV adoption rates across vehicle classes and to strengthen the engagement of different entities in the provision of charging infrastructure.
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5

Lichter, Amnon, Joseph L. Smilanick, Dennis A. Margosan, and Susan Lurie. Ethanol for postharvest decay control of table grapes: application and mode of action. United States Department of Agriculture, July 2005. http://dx.doi.org/10.32747/2005.7587217.bard.

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Original objectives: Dipping of table grapes in ethanol was determined to be an effective measure to control postharvest gray mold infection caused by Botrytis cinerea. Our objectives were to study the effects of ethanol on B.cinerea and table grapes and to conduct research that will facilitate the implementation of this treatment. Background: Botrytis cinerea is known as the major pathogen of table grapes in cold storage. To date, the only commercial technology to control it relied on sulfur dioxide (SO₂) implemented by either fumigation of storage facilities or from slow release generator pads which are positioned directly over the fruits. This treatment is very effective but it has several drawbacks such as aftertaste, bleaching and hypersensitivity to humans which took it out of the GRAS list of compounds and warranted further seek for alternatives. Prior to this research ethanol was shown to control several pathogens in different commodities including table grapes and B. cinerea. Hence it seemed to be a simple and promising technology which could offer a true alternative for storage of table grapes. Further research was however required to answer some practical and theoretical questions which remained unanswered. Major conclusions, solutions, achievements: In this research project we have shown convincingly that 30% ethanol is sufficient to prevent germination of B. cinerea and kill the spores. In a comparative study it was shown that Alternaria alternata is also rather sensitive but Rhizopus stolonifer and Aspergillus niger are less sensitive to ethanol. Consequently, ethanol protected the grapes from decay but did not have a significant effect on occurrence of mycotoxigenic Aspergillus species which are present on the surface of the berry. B. cinerea responded to ethanol or heat treatments by inducing sporulation and transient expression of the heat shock protein HSP104. Similar responses were not detected in grape berries. It was also shown that application of ethanol to berries did not induce subsequent resistance and actually the berries were slightly more susceptible to infection. The heat dose required to kill the spores was determined and it was proven that a combination of heat and ethanol allowed reduction of both the ethanol and heat dose. Ethanol and heat did not reduce the amount or appearance of the wax layers which are an essential component of the external protection of the berry. The ethanol and acetaldehyde content increased after treatment and during storage but the content was much lower than the natural ethanol content in other fruits. The efficacy of ethanol applied before harvest was similar to that of the biological control agent, Metschnikowia fructicola, Finally, the performance of ethanol could be improved synergistically by packaging the bunches in modified atmosphere films which prevent the accumulation of free water. Implications, both scientific and agricultural: It was shown that the major mode of action of ethanol is mediated by its lethal effect on fungal inoculum. Because ethanol acts mainly on the cell membranes, it was possible to enhance its effect by lowering the concentration and elevating the temperature of the treatment. Another important development was the continuous protection of the treated bunches by modified atmosphere that can solve the problem of secondary or internal infection. From the practical standpoint, a variety of means were offered to enhance the effect of the treatment and to offer a viable alternative to SO2 which could be instantly adopted by the industry with a special benefit to growers of organic grapes.
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6

Manulis-Sasson, Shulamit, Christine D. Smart, Isaac Barash, Laura Chalupowicz, Guido Sessa, and Thomas J. Burr. Clavibacter michiganensis subsp. michiganensis-tomato interactions: expression and function of virulence factors, plant defense responses and pathogen movement. United States Department of Agriculture, February 2015. http://dx.doi.org/10.32747/2015.7594405.bard.

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Clavibactermichiganensissubsp. michiganensis(Cmm), the causal agent of bacterial wilt and canker of tomato, is the most destructive bacterial disease of tomato causing substantial economic losses in Israel, the U.S.A. and worldwide. The goal of the project was to unravel the molecular strategies that allow Cmm, a Gram-positive bacterium, to develop a successful infection in tomato. The genome of Cmm contains numerous genes encoding for extracellular serine proteases and cell wall degrading enzymes. The first objective was to elucidate the role of secreted serine proteases in Cmm virulence. Mutants of nine genes encoding serine proteases of 3 different families were tested for their ability to induce wilting, when tomato stems were puncture-inoculated, as compared to blisters formation on leaves, when plants were spray-inoculated. All the mutants showed reduction in wilting and blister formation as compared to the wild type. The chpCmutant displayed the highest reduction, implicating its major role in symptom development. Five mutants of cell wall degrading enzymes and additional genes (i.e. perforin and sortase) caused wilting but were impaired in their ability to form blisters on leaves. These results suggest that Cmm differentially expressed virulence genes according to the site of penetration. Furthermore, we isolated and characterized two Cmmtranscriptional activators, Vatr1 and Vatr2 that regulate the expression of virulence factors, membrane and secreted proteins. The second objective was to determine the effect of bacterial virulence genes on movement of Cmm in tomato plants and identify the routes by which the pathogen contaminates seeds. Using a GFP-labeledCmm we could demonstrate that Cmm extensively colonizes the lumen of xylem vessels and preferentially attaches to spiral secondary wall thickening of the protoxylem and formed biofilm-like structures composed of large bacterial aggregates. Our findings suggest that virulence factors located on the chp/tomAPAI or the plasmids are required for effective movement of the pathogen in tomato and for the formation of cellular aggregates. We constructed a transposon plasmid that can be stably integrated into Cmm chromosome and express GFP, in order to follow movement to the seeds. Field strains from New York that were stably transformed with this construct, could not only access seeds systemically through the xylem, but also externally through tomato fruit lesions, which harbored high intra-and intercellular populations. Active movement and expansion of bacteria into the fruit mesocarp and nearby xylem vessels followed, once the fruit began to ripen. These results highlight the ability of Cmm to invade tomato fruit and seed through multiple entry routes. The third objective was to assess correlation between disease severity and expression levels of Cmm virulence genes and tomato defense genes. The effect of plant age on expression of tomato defense related proteins during Cmm infection was analyzed by qRT-PCR. Five genes out of eleven showed high induction at early stages of infection of plants with 19/20 leaves compared to young plants bearing 7/8 leaves. Previous results showed that Cmm virulence genes were expressed at early stages of infection in young plants compared to older plants. Results of this study suggest that Cmm virulence genes may suppress expression of tomato defense-related genes in young plants allowing effective disease development. The possibility that chpCis involved in suppression of tomato defense genes is currently under investigation by measuring the transcript level of several PR proteins, detected previously in our proteomics study. The fourth objective was to define genome location and stability of virulence genes in Cmm strains. New York isolates were compared to Israeli, Serbian, and NCPPB382 strains. The plasmid profiles of New York isolates were diverse and differed from both Israeli and Serbian strains. PCR analysis indicated that the presence of putative pathogenicity genes varied between isolates and highlighted the ephemeral nature of pathogenicity genes in field populations of Cmm. Results of this project significantly contributed to the understanding of Cmm virulence, its movement within tomato xylem or externally into the seeds, the role of serine proteases in disease development and initiated research on global regulation of Cmm virulence. These results form a basis for developing new strategies to combat wilt and canker disease of tomato.
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