scholarly journals Pace and stability of embryonic development affect telomere dynamics: an experimental study in a precocial bird model

2020 ◽  
Vol 287 (1933) ◽  
pp. 20201378 ◽  
Author(s):  
Antoine Stier ◽  
Neil B. Metcalfe ◽  
Pat Monaghan

Prenatal effects on telomere length are increasingly recognized as a potential contributor to the developmental origin of health and adult disease. While it is becoming clear that telomere length is influenced by prenatal conditions, the factors affecting telomere dynamics during embryogenesis remain poorly understood. We manipulated both the pace and stability of embryonic development through varying incubation temperature and its stability in Japanese quail. We investigated the impact on telomere dynamics from embryogenesis to adulthood, together with three potential drivers of telomere shortening, growth rate, oxidative damage and prenatal glucocorticoid levels. Telomere length was not affected by our prenatal manipulation for the first 75% of embryogenesis, but was reduced at hatching in groups experiencing faster (i.e. high temperature) or less stable embryonic development. These early life differences in telomere length persisted until adulthood. The effect of developmental instability on telomere length at hatching was potentially mediated by an increased secretion of glucocorticoid hormones during development. Both the pace and the stability of embryo development appear to be key factors determining telomere length and dynamics into adulthood, with fast and less stable development leading to shorter telomeres, with the potential for adverse associated outcomes in terms of reduced longevity.

2019 ◽  
Author(s):  
Antoine Stier ◽  
Neil B. Metcalfe ◽  
Pat Monaghan

AbstractPre-natal effects on telomere length are increasingly recognized as a potential contributor to the developmental origin of health and adult diseases. While it is becoming clear that telomere length is strongly influenced by pre-natal conditions, the factors affecting telomere dynamics during embryogenesis remain poorly understood. We manipulated both the pace and stability of prenatal growth using incubation temperature in Japanese quail and investigated the impact on telomere dynamics from embryogenesis to adulthood, along with potential drivers of telomere shortening such as oxidative damage and prenatal glucocorticoid levels. Telomere length was not affected by these manipulations for the first 75% of prenatal development, but was reduced at hatching in response to both experimentally induced fast embryo growth and growth instability. These early-life effects on telomere length persisted until adulthood. The effect of developmental instability on telomere length at hatching was potentially mediated by an increased secretion of glucocorticoid hormones during development. Both the pace and the stability of prenatal growth appear as key factors determining telomere length and dynamics up to adulthood, with fast and unstable embryo growth leading to short telomeres with the potential for adverse associated outcomes in terms of reduced longevity and greater risk of disease.


2017 ◽  
Vol 73 (7) ◽  
pp. 618-625 ◽  
Author(s):  
Nicole Balasco ◽  
Luciana Esposito ◽  
Luigi Vitagliano

The protein folded state is the result of the fine balance of a variety of different forces. Even minor structural perturbations may have a significant impact on the stability of these macromolecules. Studies carried out in recent decades have led to the convergent view that proteins are endowed with a flexible spine. One of the open issues related to protein local backbone geometry is the identification of the factors that influence the amplitude of the τ (N—Cα—C) angle. Here, statistical analyses performed on an updated ensemble of X-ray protein structures by dissecting the contribution of the major factors that can potentially influence the local backbone geometry of proteins are reported. The data clearly indicate that the local backbone conformation has a prominent impact on the modulation of the τ angle. Therefore, a proper assessment of the impact of the other potential factors can only be appropriately evaluated when small (φ, ψ) regions are considered. Here, it is shown that when the contribution of the backbone conformation is removed by considering small (φ, ψ) areas, an impact of secondary structure, as defined byDSSP, and/or the residue type on τ is still detectable, although to a limited extent. Indeed, distinct τ-value distributions are detected for Pro/Gly and β-branched (Ile/Val) residues. The key role of the local backbone conformation highlighted here supports the use of variable local backbone geometry in protein refinement protocols.


Author(s):  
David Miles ◽  
Adrian Heald ◽  
Mike Stedman

Vaccination against the COVID-19 virus began in December 2020 in the UK and is now running at 5% population/week. High Levels of social restrictions were implemented for the third time in January 2021 to control the second wave and resulting increases in hospitalisations and deaths. Easing those restrictions must balance multiple challenging priorities, weighing the risk of more deaths and hospitalisations against damage done to mental health, incomes and standards of living, education outcomes and provision of non-Covid-19 healthcare. Weekly and monthly officially published values in 2020/21 were used to estimate the impact of seasonality and social restrictions on the spread of COVID-19 by age group, on the economy and healthcare services. These factors were combined with the estimated impact of vaccinations and immunity from past infections into a model that retrospectively reflected the actual numbers of reported deaths closely both in 2020 and early 2021. It was applied prospectively to the next 6 months to evaluate the impact of different speeds of easing social restrictions. The results show vaccinations are significantly reducing the number of hospitalisations and deaths. The central estimate is that relative to a rapid easing, the avoided loss of 57,000 life years from a strategy of relatively slow easing over the next 4 months comes at a cost in terms of GDP reduction of around £0.4 million/life-year loss avoided. This is over 10 times higher than the usual limit the NHS uses for spending against Quality Adjusted Life Years (QALYs) saved. Alternative assumptions for key factors affecting give significantly different trade-offs between costs and benefits of different speeds of easing. Disruption of non-Covid-19 Healthcare provision also increases in times of higher levels of social restrictions. In most cases, the results favour a somewhat faster easing of restrictions in England than current policy implies.


Author(s):  
Colleen Cunningham ◽  
Il-Yeol Song

Customer relationship management (CRM) is a strategy that integrates concepts of knowledge management, data mining, and data warehousing in order to support an organization’s decision-making process to retain long-term and profitable relationships with its customers. Key factors for successfully implementing CRM (e.g., data quality issues, organizational readiness, customer strategies, selection of appropriate KPIs, and the design of the data warehouse model) are discussed with the main thrust of the chapter focusing on CRM analyses and the impact of those analyses on CRM data warehousing design decisions. This chapter then presents a robust multidimensional starter model that supports CRM analyses. Additional research contributions include the introduction of two new measures, percent success ratio and CRM suitability ratio by which CRM models can be evaluated, the identification/ classification of CRM queries, and a preliminary heuristic for designing data warehouses to support CRM analyses.


2015 ◽  
Vol 60 (3) ◽  
pp. 2131-2137 ◽  
Author(s):  
M. Gruber ◽  
S. Ploberger ◽  
G. Ressel ◽  
M. Wiessner ◽  
M. Hausbauer ◽  
...  

Abstract The stability of austenite is one of the most dominant factors affecting the toughness properties of high Co-Ni steels such as Aermet 100 and AF1410. Thus, the aim of this work was to get a deeper understanding on the impact of combined heat and cryogenic treatment on the stability of retained and reverted austenite. In order to characterize the evolution of the phase fraction of austenite during tempering at different temperatures and times, X-ray diffraction analyses were carried out. The stability of austenite, which was formed during tempering, was analyzed with dilatometric investigations by studying the transformation behavior of the austenite during cooling from tempering temperature down to −100°C. Additionally, transmission electron microscopy investigations were performed to characterize the chemical composition and phase distribution of austenite and martensite before and after tempering.


Antioxidants ◽  
2021 ◽  
Vol 10 (12) ◽  
pp. 1967
Author(s):  
Bianca Enaru ◽  
Georgiana Drețcanu ◽  
Teodora Daria Pop ◽  
Andreea Stǎnilǎ ◽  
Zorița Diaconeasa

Anthocyanins are secondary metabolites and water-soluble pigments belonging to the phenolic group, with important functions in nature such as seed dispersal, pollination and development of plant organs. In addition to these important roles in plant life, anthocyanins are also used as natural pigments in various industries, due to the color palette they can produce from red to blue and purple. In addition, recent research has reported that anthocyanins have important antioxidant, anticancer, anti-inflammatory and antimicrobial properties, which can be used in the chemoprevention of various diseases such as diabetes, obesity and even cancer. However, anthocyanins have a major disadvantage, namely their low stability. Thus, their stability is influenced by a number of factors such as pH, light, temperature, co-pigmentation, sulfites, ascorbic acid, oxygen and enzymes. As such, this review aims at summarizing the effects of these factors on the stability of anthocyanins and their degradation. From this point of view, it is very important to be precisely aware of the impact that each parameter has on the stability of anthocyanins, in order to minimize their negative action and subsequently potentiate their beneficial health effects.


Micromachines ◽  
2021 ◽  
Vol 12 (8) ◽  
pp. 982
Author(s):  
Shuhan Cheng ◽  
Xia Li ◽  
Yongkun Wang ◽  
Yufeng Su

A diamagnetically stabilized levitation structure is composed of a floating magnet, diamagnetic material, and a lifting magnet. The floating magnet is freely levitated between two diamagnetic plates without any external energy input. In this paper, the levitation characteristics of a floating magnet were firstly studied through simulation. Three different levitation states were found by adjusting the gap between the two diamagnetic plates, namely symmetric monostable levitation, bistable levitation, and asymmetric monostable levitation. Then, according to experimental comparison, it was found that the stability of the symmetric monostable levitation system is better than that of the other two. Lastly, the maximum moving space that allows the symmetric monostable levitation state is investigated by Taguchi method. The key factors affecting the maximum gap were determined as the structure parameters of the floating magnet and the thickness of highly oriented pyrolytic graphite (HOPG) sheets. According to the optimal parameters, work performance was obtained by an experiment with an energy harvester based on the diamagnetic levitation structure. The effective value of voltage is 250.69 mV and the power is 86.8 μW. An LED light is successfully lit on when the output voltage is boosted with a Cockcroft–Walton cascade voltage doubler circuit. This work offers an effective method to choose appropriate parameters for a diamagnetically stabilized levitation structure.


Author(s):  
Tzu-Tsung Wong ◽  
Shih-Hsuan Hung

Topcoat paint is mainly composed of resin and pigment and hence its quality highly depends on the type and proportion of these two ingredients. This study aims at testing the formula of the topcoat paint for finding one that can achieve better quality for anti-aging. Various formulas of paint are applied on boards that will be put into ultraviolet accelerated test machines to simulate weathering tests. The gloss and color, before and after the tests, are collected and numerical prediction method M5P is used to grow model trees for discovering the key factors affecting aging. Based on the structure and the linear regression models in the trees, a better topcoat paint should be composed of a high proportion of resin and generally a low proportion of pigment. Good types of resin and pigment are also identified for keeping color and gloss.


Author(s):  
Tran Thi-Kim Nhung ◽  
Nguyen Thanh Do

As academic activities and research performances become important criteria in evaluating the quality of a university, research activities have received a special concern from universities. The key questions are what prompts faculty members to do research and how to motivate them. In order to answer these questions, it is necessary to examine the factors affecting the research motivation, then measure the impact of these factors on the faculty members' research motivation. In this study, the authors employed the expansive expectancy theory proposed by Chiang & Jang to investigate key factors that motivate faculty members to conduct research. The regression results on data collected from a survey on 475 faculty members at universities in Hanoi showed that faculty members are motivated by the intrinsic instrumentality factor (INTIN), financial value factor (FINVA) and expectancy factor (EXPECT – the factor that yields controversial results in previous studies). These findings suggest that the research motivation of lecturers has a positive correlation with academic degree, administrative position and has no relationship with age and gender.  


2021 ◽  
Vol 10 (3) ◽  
Author(s):  
Omar Khaleel ◽  
Sultan Mohamed Al Mandhari

The claim during the implementation of projects is very important for the contractor and the consultant. As for the owner, it is considered expensive and cumbersome,and therefore the project contract must be very clear so that there are no gaps or defects against the owner.The aim of this research is to analyze and study deeply contractor's claim.The objectives of this study are to study the main factors for the contractor's claim to the commercial pier project in the Sultanate of Oman,including eleven factors. The second objective is to study the impact of the contractor's claim on the commercial pier project in the Sultanate of Oman, and it includes five factors, as the questionnaire was distributed to customers and various segments of society.The results of analyzing 16 factors to identify the key factors and the impact of the study of the contractors claim conclude that the main factors affecting the contactor's claim to the pier project.The factors and impacts are valid to the study after conducting analysis on the obtained data. The factors include the development unexpected weather conditions, inconsideration of the time frame, government approval of delays,poor coordination with the project parties, poor site management and supervision,a change in the clients requirements, the lack of experienced staff, incompetence among teams, low items in the bill of products,and misunderstanding the scope of work and specifications.The impacts to the completion of the Berth project include payment delays, delays in the extension of time,issuing variation order,value implementation engineering and cost reduction,and contractor's performance.


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