Articles de revues : « Extended Synthesis of Evolution »

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Pigliucci, Massimo, et Gerd B. Müller. « Comentarios Bibliográficos : Evolution : the extended synthesis. 2010. » Natura Neotropicalis 1, n^o 41 (21 avril 2010) : 67–69. http://dx.doi.org/10.14409/natura.v1i41.3887.

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Prentiss, Anna Marie. « Theoretical plurality, the extended evolutionary synthesis, and archaeology ». Proceedings of the National Academy of Sciences 118, n^o 2 (5 janvier 2021) : e2006564118. http://dx.doi.org/10.1073/pnas.2006564118.

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The study of cultural evolution now includes multiple theoretical frameworks. Despite common influence from Darwinian evolutionary theory, there is considerable diversity. Thus, we recognize those most influenced by the tenets of the Modern Synthesis (evolutionary archaeology, cultural transmission theory, and human behavioral ecology) and those most aligned more closely with concepts emerging in the Extended Evolutionary Synthesis (cultural macroevolution and evolutionary cognitive archaeology). There has been substantial debate between adherents of these schools of thought as to their appropriateness and priority for addressing the fundamentals of cultural evolution. I argue that theoretical diversity is necessary to address research questions arising from a complex archaeological record. Concepts associated with the Extended Evolutionary Synthesis may offer unique insights into the cultural evolutionary process.

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Szokolszky, Ágnes, et Zsolt Palatinus. « Changing views of evolution and their consequences for psychology. From the Modern Synthesis to the Extended Synthesis, and beyond ». Transylvanian Journal of Psychology 20, n^o 2 (20 décembre 2019) : 3–60. http://dx.doi.org/10.24193/tjp.xx.2.1.

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Reductionist viewpoints have been increasingly replaced by complex systems viewpoints in biological theory and methodology since the turn of the millennium. This tendency has also been reflected in thinking about evolution. Just as the defining evolutionary synthesis of the 20th century - the Modern Synthesis - was born out of the integration of the most up-to-date knowledge of the times, so does a recently emerging new synthesis build on most recent genetic-epigenetic, genomic, eco-devo-evolutionary findings. The "Extended Synthesis" (Pigliucci & Müller, 2010) builds on current understanding of genes, heredity, and multiple evolutionary processes. In this framework, an extended interpretation is offered based on the integration of evolutionary and ecosystem-level processes into the explanation of evolution. In this paper, we aim to review the paths leading to the Extended Synthesis. We aim to present a historically embedded, concise overview of the major issues and developments related to the changing perspectives. The final point of the discussion eventually raises the question: How does psychology relate to the extended view of evolution?

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Schrey, Aaron W., Christina L. Richards, Victoria Meller, Vincent Sollars et Douglas M. Ruden. « The Role of Epigenetics in Evolution : The Extended Synthesis ». Genetics Research International 2012 (5 mars 2012) : 1–3. http://dx.doi.org/10.1155/2012/286164.

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Brooks, Daniel R. « The Major Metaphors of Evolution : Visualizing the Extended Synthesis ». Evolution : Education and Outreach 4, n^o 3 (septembre 2011) : 446–52. http://dx.doi.org/10.1007/s12052-011-0360-3.

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Laland, Kevin N., Tobias Uller, Marcus W. Feldman, Kim Sterelny, Gerd B. Müller, Armin Moczek, Eva Jablonka et John Odling-Smee. « The extended evolutionary synthesis : its structure, assumptions and predictions ». Proceedings of the Royal Society B : Biological Sciences 282, n^o 1813 (22 août 2015) : 20151019. http://dx.doi.org/10.1098/rspb.2015.1019.

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Scientific activities take place within the structured sets of ideas and assumptions that define a field and its practices. The conceptual framework of evolutionary biology emerged with the Modern Synthesis in the early twentieth century and has since expanded into a highly successful research program to explore the processes of diversification and adaptation. Nonetheless, the ability of that framework satisfactorily to accommodate the rapid advances in developmental biology, genomics and ecology has been questioned. We review some of these arguments, focusing on literatures (evo-devo, developmental plasticity, inclusive inheritance and niche construction) whose implications for evolution can be interpreted in two ways—one that preserves the internal structure of contemporary evolutionary theory and one that points towards an alternative conceptual framework. The latter, which we label the ‘extended evolutionary synthesis' (EES), retains the fundaments of evolutionary theory, but differs in its emphasis on the role of constructive processes in development and evolution, and reciprocal portrayals of causation. In the EES, developmental processes, operating through developmental bias, inclusive inheritance and niche construction, share responsibility for the direction and rate of evolution, the origin of character variation and organism–environment complementarity. We spell out the structure, core assumptions and novel predictions of the EES, and show how it can be deployed to stimulate and advance research in those fields that study or use evolutionary biology.

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Brooks, Daniel R., et Salvatore J. Agosta. « Children of time : the extended synthesis and major metaphors of evolution ». Zoologia (Curitiba) 29, n^o 6 (décembre 2012) : 497–514. http://dx.doi.org/10.1590/s1984-46702012000600002.

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Kang, Sangmin, Ja-Jung Koo, Hongmin Seo, Quang Trung Truong, Jong Bo Park, Seong Chae Park, Youngjin Jung et al. « Defect-engineered MoS2 with extended photoluminescence lifetime for high-performance hydrogen evolution ». Journal of Materials Chemistry C 7, n^o 33 (2019) : 10173–78. http://dx.doi.org/10.1039/c9tc02256b.

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Müller, Gerd B. « Why an extended evolutionary synthesis is necessary ». Interface Focus 7, n^o 5 (18 août 2017) : 20170015. http://dx.doi.org/10.1098/rsfs.2017.0015.

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Since the last major theoretical integration in evolutionary biology—the modern synthesis (MS) of the 1940s—the biosciences have made significant advances. The rise of molecular biology and evolutionary developmental biology, the recognition of ecological development, niche construction and multiple inheritance systems, the ‘-omics’ revolution and the science of systems biology, among other developments, have provided a wealth of new knowledge about the factors responsible for evolutionary change. Some of these results are in agreement with the standard theory and others reveal different properties of the evolutionary process. A renewed and extended theoretical synthesis, advocated by several authors in this issue, aims to unite pertinent concepts that emerge from the novel fields with elements of the standard theory. The resulting theoretical framework differs from the latter in its core logic and predictive capacities. Whereas the MS theory and its various amendments concentrate on genetic and adaptive variation in populations, the extended framework emphasizes the role of constructive processes, ecological interactions and systems dynamics in the evolution of organismal complexity as well as its social and cultural conditions. Single-level and unilinear causation is replaced by multilevel and reciprocal causation. Among other consequences, the extended framework overcomes many of the limitations of traditional gene-centric explanation and entails a revised understanding of the role of natural selection in the evolutionary process. All these features stimulate research into new areas of evolutionary biology.

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Dickins, Thomas E., et Qazi Rahman. « The extended evolutionary synthesis and the role of soft inheritance in evolution ». Proceedings of the Royal Society B : Biological Sciences 279, n^o 1740 (16 mai 2012) : 2913–21. http://dx.doi.org/10.1098/rspb.2012.0273.

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In recent years, a number of researchers have advocated extending the modern synthesis in evolutionary biology. One of the core arguments made in favour of an extension comes from work on soft inheritance systems, including transgenerational epigenetic effects, cultural transmission and niche construction. In this study, we outline this claim and then take issue with it. We argue that the focus on soft inheritance has led to a conflation of proximate and ultimate causation, which has in turn obscured key questions about biological organization and calibration across the life span to maximize average lifetime inclusive fitness. We illustrate this by presenting hypotheses that we believe incorporate the core phenomena of soft inheritance and will aid in understanding them.

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Švorcová, Jana, et Karel Kleisner. « Evolution by Meaning Attribution : Notes on Biosemiotic Interpretations of Extended Evolutionary Synthesis ». Biosemiotics 11, n^o 2 (24 mai 2018) : 231–44. http://dx.doi.org/10.1007/s12304-018-9328-9.

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Olson, Mark E. « Plant Evolutionary Ecology in the Age of the Extended Evolutionary Synthesis ». Integrative and Comparative Biology 59, n^o 3 (20 mai 2019) : 493–502. http://dx.doi.org/10.1093/icb/icz042.

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AbstractPlant ecology is increasingly turning to evolutionary questions, just as evolutionary biology pushes out of the strictures of the Modern Synthesis into what some regard as an “Extended Evolutionary Synthesis.” As plant ecology becomes increasingly evolutionary, it is essential to ask how aspects of the Extended Synthesis might impinge on plant ecological theory and practice. I examine the contribution of plant evolutionary ecology to niche construction theory, as well as the potential for developmental systems theory and genes-as-followers adaptive evolution, all important post-Modern Synthesis themes, in providing novel perspectives for plant evolutionary ecology. I also examine ways that overcoming dichotomies such as “genetic vs. plastic” and “constraint vs. adaptation” provide fertile opportunities for plant evolutionary ecologists. Along the same lines, outgrowing vague concepts such as “stress” and replacing them with more precise terminology in all cases provides vastly increased causal clarity. As a result, the synthetic path that plant ecologists are blazing, becoming more evolutionary every year, bodes extremely well for the field, with vast potential for expansion into important scientific territory.

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Futuyma, Douglas J. « Evolutionary biology today and the call for an extended synthesis ». Interface Focus 7, n^o 5 (18 août 2017) : 20160145. http://dx.doi.org/10.1098/rsfs.2016.0145.

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Evolutionary theory has been extended almost continually since the evolutionary synthesis (ES), but except for the much greater importance afforded genetic drift, the principal tenets of the ES have been strongly supported. Adaptations are attributable to the sorting of genetic variation by natural selection, which remains the only known cause of increase in fitness. Mutations are not adaptively directed, but as principal authors of the ES recognized, the material (structural) bases of biochemistry and development affect the variety of phenotypic variations that arise by mutation and recombination. Against this historical background, I analyse major propositions in the movement for an ‘extended evolutionary synthesis’. ‘Niche construction' is a new label for a wide variety of well-known phenomena, many of which have been extensively studied, but (as with every topic in evolutionary biology) some aspects may have been understudied. There is no reason to consider it a neglected ‘process’ of evolution. The proposition that phenotypic plasticity may engender new adaptive phenotypes that are later genetically assimilated or accommodated is theoretically plausible; it may be most likely when the new phenotype is not truly novel, but is instead a slight extension of a reaction norm already shaped by natural selection in similar environments. However, evolution in new environments often compensates for maladaptive plastic phenotypic responses. The union of population genetic theory with mechanistic understanding of developmental processes enables more complete understanding by joining ultimate and proximate causation; but the latter does not replace or invalidate the former. Newly discovered molecular phenomena have been easily accommodated in the past by elaborating orthodox evolutionary theory, and it appears that the same holds today for phenomena such as epigenetic inheritance. In several of these areas, empirical evidence is needed to evaluate enthusiastic speculation. Evolutionary theory will continue to be extended, but there is no sign that it requires emendation.

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Antón, Susan C., et Christopher W. Kuzawa. « Early Homo , plasticity and the extended evolutionary synthesis ». Interface Focus 7, n^o 5 (18 août 2017) : 20170004. http://dx.doi.org/10.1098/rsfs.2017.0004.

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The Modern Synthesis led to fundamental advances in understandings of human evolution. For human palaeontology, a science that works from ancestral phenotypes (i.e. the fossil record), particularly important have been perspectives used to help understand the heritable aspects of phenotypes and how fossil individuals might then be aggregated into species, and relationships among these groups understood. This focus, coupled with the fragmentary nature of the fossil record, however, means that individual phenotypic variation is often treated as unimportant ‘noise’, rather than as a source of insight into population adaptation and evolutionary process. The emphasis of the extended evolutionary synthesis on plasticity as a source of phenotypic novelty, and the related question of the role of such variation in long-term evolutionary trends, focuses welcome attention on non-genetic means by which novel phenotypes are generated and in so doing provides alternative approaches to interpreting the fossil record. We review evidence from contemporary human populations regarding some of the aspects of adult phenotypes preserved in the fossil record that might be most responsive to non-genetic drivers, and we consider how these perspectives lead to alternate hypotheses for interpreting the fossil record of early genus Homo. We conclude by arguing that paying closer attention to the causes and consequences of intraspecific phenotypic variation in its own right, as opposed to as noise around a species mean, may inspire a new generation of hypotheses regarding species diversity in the Early Pleistocene and the foundations for dispersal and regional diversification in Homo erectus and its descendants .

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Zeder, Melinda A. « Domestication as a model system for the extended evolutionary synthesis ». Interface Focus 7, n^o 5 (18 août 2017) : 20160133. http://dx.doi.org/10.1098/rsfs.2016.0133.

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One of the challenges in evaluating arguments for extending the conceptual framework of evolutionary biology involves the identification of a tractable model system that allows for an assessment of the core assumptions of the extended evolutionary synthesis (EES). The domestication of plants and animals by humans provides one such case study opportunity. Here, I consider domestication as a model system for exploring major tenets of the EES. First I discuss the novel insights that niche construction theory (NCT, one of the pillars of the EES) provides into the domestication processes, particularly as they relate to five key areas: coevolution, evolvability, ecological inheritance, cooperation and the pace of evolutionary change. This discussion is next used to frame testable predictions about initial domestication of plants and animals that contrast with those grounded in standard evolutionary theory, demonstrating how these predictions might be tested in multiple regions where initial domestication took place. I then turn to a broader consideration of how domestication provides a model case study consideration of the different ways in which the core assumptions of the EES strengthen and expand our understanding of evolution, including reciprocal causation, developmental processes as drivers of evolutionary change, inclusive inheritance, and the tempo and rate of evolutionary change.

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Fábregas-Tejeda, Alejandro, et Francisco Vergara-Silva. « Hierarchy Theory of Evolution and the Extended Evolutionary Synthesis : Some Epistemic Bridges, Some Conceptual Rifts ». Evolutionary Biology 45, n^o 2 (1 novembre 2017) : 127–39. http://dx.doi.org/10.1007/s11692-017-9438-3.

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Lamas, Susana Gisela. « El ideal de unificación en biología : el caso de la síntesis evolutiva extendida ». Humanities Journal of Valparaiso, n^o 14 (29 décembre 2019) : 275. http://dx.doi.org/10.22370/rhv2019iss14pp275-286.

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In this article I will analyze whether the so-called Extended Evolutionary Synthesis (EES) represents a synthesis and an extension with respect to its predecessor, Modern Synthesis (MS). It will be argued that the MS proposes an externalist approach to evolution while the EES considers it necessary to overcome the internalism/externalism dichotomy by proposing more integrative approaches. It will be concluded that the EES cannot be considered an extension of MS and that the appeal to that extension is related to sociological aspects and the epistemic value of theoretical unification that was always present in biological evolutionary thinking.

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Blute, Marion. « Three Modes of Evolution by Natural Selection and Drift : A New or an Extended Evolutionary Synthesis ? » Biological Theory 12, n^o 2 (7 avril 2017) : 67–71. http://dx.doi.org/10.1007/s13752-017-0264-8.

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Badillo-Olvera, A., A. Pérez-González, O. Begovich et J. Ruíz-León. « Burst detection and localization in water pipelines based on an extended differential evolution algorithm ». Journal of Hydroinformatics 21, n^o 4 (1 avril 2019) : 593–606. http://dx.doi.org/10.2166/hydro.2019.123.

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Abstract This paper presents a new burst detection and location technique for pressurized pipelines based on an extension of the Differential Evolution (DE) algorithm. The proposed approach addresses the burst location problem as an optimization task, by considering the dynamic model that describes the behavior of a fluid through a pipeline and the presence of fluid losses produced by a burst. The optimization problem relies on finding suitable estimations related to the burst parameters, i.e. magnitude, pressure and position of a burst, while a defined cost function is minimized. In order to deal with this problem, three strategies are proposed to extend and adapt the DE algorithm: (i) an informed definition of the physical restrictions of the problem according to the pipeline characteristics; (ii) a training stage of the algorithm that allows to find the appropriate synthesis parameters; (iii) a multi-start structure, in order to track dynamical variations of the problem. Experiments on a pipeline prototype illustrate the results obtained by the proposed algorithm on the estimation of the burst parameters, comparing its performance with an algorithm based on the Extended Kalman Filter, which is widely used in the literature.

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Cai, Chen, Zongwei Xin, Xuefan Zhang, Jian Cui, Hui Lv, Wanjie Ren, Cunyuan Gao et Bin Cai. « Facile Synthesis of FeCoNiCuIr High Entropy Alloy Nanoparticles for Efficient Oxygen Evolution Electrocatalysis ». Catalysts 12, n^o 9 (15 septembre 2022) : 1050. http://dx.doi.org/10.3390/catal12091050.

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The lack of an efficient and stable electrocatalyst for oxygen evolution reaction (OER) greatly hinders the development of various electrochemical energy conversion and storage techniques. In this study, we report a facile synthesis of FeCoNiCuIr high-entropy alloy nanoparticles (HEA NPs) by a one-step heat-up method. The involvement of glucose made the NPs grow uniformly and increased the valence of Ir. The resulting FeCoNiCuIr NPs exhibit excellent OER performance in alkaline solution, with a low overpotential of 360 mV to achieve a current density of 10 mA cm−2 at a Tafel slope of as low as 70.1 mV dec‒1. In addition, high stability has also been observed, which remained at 94.2% of the current density after 10 h constant electrolysis, with a constant current of 10 mA cm‒2. The high electrocatalytic activity and stability are ascribed to the cocktail effect and synergistic effect between the constituent elements. Our work holds the potential to be extended to the design and synthesis of high-performance electrocatalysts.

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Singh, B. N. « Perspectives on Modern Synthetic Theory of Evolution ». JOURNAL OF SCIENTIFIC RESEARCH 66, n^o 03 (2022) : 109–16. http://dx.doi.org/10.37398/jsr.2022.660315.

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For the past more than a century, evolution has become a corner stone of biology. Different theories have been proposed to explain the mechanisms of evolution such as Lamarckism, Darwinism, germ plasm theory, isolation theory, mutation theory, modern synthetic theory and neutral theory. Among these theories, emphasis is mostly given on single factors. However, modern synthetic theory combines different factors into one theory, particularly natural selection and Mendelian genetics that is why the word synthetic theory is used. Presently, it is the most widely accepted theory to explain the mechanism of evolution although it owes more to Darwin than to any other evolutionary biologist and is essentially built around the concept of natural selection. However, it incorporates much that is post-Darwinian. This theory offers the most widely accepted explanation for the mechanism of evolution and is based on factors such as gene mutations, structural and numerical alterations in chromosomes, genetic recombination, natural selection, random genetic drift, migration, hybridization and reproductive isolation. Further, some recent work in the field of molecular biology have thrown light on the mechanisms of evolution. The new biology goes beyond the modern synthesis, it integrates together genomics, bioinformatics, evolutionary genetics and molecular biology to provide novel explanations, and in the light of these findings, the OMS should be modified or extended. Even there is a suggestion to propose a new theory of evolution as a coherent alternative to modern synthesis

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Lewens, Tim. « The Extended Evolutionary Synthesis : what is the debate about, and what might success for the extenders look like ? » Biological Journal of the Linnean Society 127, n^o 4 (21 mai 2019) : 707–21. http://dx.doi.org/10.1093/biolinnean/blz064.

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Abstract Debate over the Extended Evolutionary Synthesis (EES) ranges over three quite different domains of enquiry. Protagonists are committed to substantive positions regarding (1) empirical questions concerning (for example) the properties and prevalence of systems of epigenetic inheritance; (2) historical characterizations of the modern synthesis; and (3) conceptual/philosophical matters concerning (among other things) the nature of evolutionary processes, and the relationship between selection and adaptation. With these different aspects of the debate in view, it is possible to demonstrate the range of cross-cutting positions on offer when well-informed evolutionists consider their stance on the EES. This overview of the multiple dimensions of debate also enables clarification of two philosophical elements of the EES debate, regarding the status of niche-construction and the role of selection in explaining adaptation. Finally, it points the way to a possible resolution of the EES debate, via a pragmatic approach to evolutionary enquiry.

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Amato, Salvatore Ivan. « EvoDevo : An Ongoing Revolution ? » Philosophies 5, n^o 4 (5 novembre 2020) : 35. http://dx.doi.org/10.3390/philosophies5040035.

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Since its appearance, Evolutionary Developmental Biology (EvoDevo) has been called an emerging research program, a new paradigm, a new interdisciplinary field, or even a revolution. Behind these formulas, there is the awareness that something is changing in biology. EvoDevo is characterized by a variety of accounts and by an expanding theoretical framework. From an epistemological point of view, what is the relationship between EvoDevo and previous biological tradition? Is EvoDevo the carrier of a new message about how to conceive evolution and development? Furthermore, is it necessary to rethink the way we look at both of these processes? EvoDevo represents the attempt to synthesize two logics, that of evolution and that of development, and the way we conceive one affects the other. This synthesis is far from being fulfilled, but an adequate theory of development may represent a further step towards this achievement. In this article, an epistemological analysis of EvoDevo is presented, with particular attention paid to the relations to the Extended Evolutionary Synthesis (EES) and the Standard Evolutionary Synthesis (SET).

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Dumas, Angela, Martín Mizrahi, François Martin et Felix G. Requejo. « Local and Extended-Order Evolution of Synthetic Talc during Hydrothermal Synthesis : Extended X-ray Absorption Fine Structure, X-ray Diffraction, and Fourier Transform Infrared Spectroscopy Studies ». Crystal Growth & ; Design 15, n^o 11 (5 octobre 2015) : 5451–63. http://dx.doi.org/10.1021/acs.cgd.5b01076.

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Li, S., H. Jiang, Z. Ren et C. Xu. « Optimal Tracking for a Divergent-Type Parabolic PDE System in Current Profile Control ». Abstract and Applied Analysis 2014 (2014) : 1–8. http://dx.doi.org/10.1155/2014/940965.

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We consider the optimal tracking problem for a divergent-type parabolic PDE system, which can be used to model the spatial-temporal evolution of the magnetic diffusion process in a tokamak plasma. With the feedforward trajectories generated by numerical optimization, we derive a linear system to describe the error evolution. The weak variation approach is then extended to cylindrical coordinates to obtain a Riccati-type PDE for feedback kernel synthesis. Then, a finite difference method is used to give numerical solutions for the Riccati-type PDE. The obtained feedback kernel is finally used to simulate the closed-loop system. The simulation results demonstrate that the proposed tracking method can attenuate the tracking error effectively.

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Hussain, Sajjad, Jinwoong Chae, Kamran Akbar, Dhanasekaran Vikraman, Linh Truong, Bilal Abbas Naqvi, Yawar Abbas et al. « Fabrication of Robust Hydrogen Evolution Reaction Electrocatalyst Using Ag2Se by Vacuum Evaporation ». Nanomaterials 9, n^o 10 (15 octobre 2019) : 1460. http://dx.doi.org/10.3390/nano9101460.

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Much research has been done on reliable and low-cost electrocatalysts for hydrogen generation by water splitting. In this study, we synthesized thin films of silver selenide (Ag2Se) using a simple thermal evaporation route and demonstrated their electrocatalytic hydrogen evolution reaction (HER) activity. The Ag2Se catalysts show improved electrochemical surface area and good HER electrocatalytic behavior (367 mV overpotential @ 10 mA·cm−2, exchange current density: ~1.02 × 10−3 mA·cm−2, and Tafel slope: 53 mV·dec−1) in an acidic medium). The reliability was checked in 0.5 M sulfuric acid over 20 h. Our first-principles calculations show the optimal energy of hydrogen adsorption, which is consistent with experimental results. The works could be further extended for finding a new catalyst by associating the selenide, sulfide or telluride-based materials without complex catalyst synthesis procedures.

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Mas-Hesse, J. Miguel, et Miguel Cerviño. « Evolutionary population synthesis : the effect of binary systems ». Symposium - International Astronomical Union 193 (1999) : 550–58. http://dx.doi.org/10.1017/s0074180900206268.

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We present in this contribution our set of multi-wavelength synthesis models including the evolution of single and binary stars. The main results we have obtained can be summarized as follows: (a) massive close-binary systems will start to experience mass transfer episodes after the first 4Myr of the starburst evolution; (b) as a result of these mass transfer processes, stars of relatively low initial mass can lose completely their envelope and become a Wolf-Rayet star. In this way, the formation of WR stars is extended over longer than 15 Myr, and does not stop at 6Myr as predicted by models including only single stars; (c) WR stars can thus be coeval with red supergiants, which peak at around 10 Myr for solar metallicities; (d) the accretion of mass will originate relatively massive stars at ages for which they should have already disappeared; these stars, together with the WR stars formed in rather evolved clusters, increase the production of ionizing photons, so that the Hβ equivalent width will not drop as rapidly as predicted by models considering only individual stars; and (e) the mass transfer to compact companions will produce an additional source of high-energy radiation in the form of high-mass X-ray binaries, not predicted either by standard synthesis models.

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Piersma, Theunis. « Flyway evolution is too fast to be explained by the modern synthesis : proposals for an ‘extended’ evolutionary research agenda ». Journal of Ornithology 152, S1 (11 juin 2011) : 151–59. http://dx.doi.org/10.1007/s10336-011-0716-z.

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Coleman, Nathaniel, Ishanka A. Liyanage, Matthew D. Lovander, Johna Leddy et Edward G. Gillan. « Facile Solvent-Free Synthesis of Metal Thiophosphates and Their Examination as Hydrogen Evolution Electrocatalysts ». Molecules 27, n^o 16 (9 août 2022) : 5053. http://dx.doi.org/10.3390/molecules27165053.

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The facile solvent-free synthesis of several known metal thiophosphates was accomplished by a chemical exchange reaction between anhydrous metal chlorides and elemental phosphorus with sulfur, or combinations of phosphorus with molecular P2S5 at moderate 500 °C temperatures. The crystalline products obtained from this synthetic approach include MPS3 (M = Fe, Co, Ni) and Cu3PS4. The successful reactions benefit from thermochemically favorable PCl3 elimination. This solvent-free route performed at moderate temperatures leads to mixed anion products with complex heteroatomic anions, such as P2S64−. The MPS3 phases are thermally metastable relative to the thermodynamically preferred separate MPx/ MSy and more metal-rich MPxSy phases. The micrometer-sized M-P-S products exhibit room-temperature optical and magnetic properties consistent with isolated metal ion structural arrangements and semiconducting band gaps. The MPS3 materials were examined as electrocatalysts in hydrogen evolution reactions (HER) under acidic conditions. In terms of HER activity at lower applied potentials, the MPS3 materials show the trend of Co > Ni >> Fe. Extended time constant potential HER experiments show reasonable HER stability of ionic and semiconducting MPS3 (M = Co, Ni) structures under acidic reducing conditions.

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Marigo, Paola, Léo Girardi, Alessandro Bressan, Bernhard Aringer, Marco Gullieuszik, Enrico V. Held, Martin A. T. Groenewegen, Laura Silva et Gian Luigi Granato. « TP-AGB stars in population synthesis models ». Proceedings of the International Astronomical Union 5, S262 (août 2009) : 36–43. http://dx.doi.org/10.1017/s1743921310002498.

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AbstractIn spite of its relevance, the Thermally Pulsing Asymptotic Giant Branch (TP-AGB) phase is one of the most uncertain phases of stellar evolution, and a major source of disagreement between the results of different population synthesis models of galaxies. I will briefly review the existing literature on the subject, and recall the basic prescriptions that have been used to fix the contribution of TP-AGB stars to the integrated light of stellar populations. The simplicity of these prescriptions greatly contrasts with the richness of details provided by present-day databases of AGB stars in the Magellanic Clouds, which are now being extended to other nearby galaxies. I will present the first results of an ongoing study aimed at simulating photometry, chemistry, pulsation, mass loss, dust properties of AGB star populations in resolved and un-resolved galaxies. We test our predictions against observations from various surveys of the Magellanic Clouds (DENIS, 2MASS, OGLE, MACHO, Spitzer, and AKARI). I will discuss the implications and outline the plan of future developments.

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Mikkelsen, Jacob Giehm, Anders H. Lund, Karen Dybkær, Mogens Duch et Finn Skou Pedersen. « Extended Minus-Strand DNA as Template for R-U5-Mediated Second-Strand Transfer in Recombinational Rescue of Primer Binding Site-Modified Retroviral Vectors ». Journal of Virology 72, n^o 3 (1 mars 1998) : 2519–25. http://dx.doi.org/10.1128/jvi.72.3.2519-2525.1998.

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ABSTRACT We have previously demonstrated recombinational rescue of primer binding site (PBS)-impaired Akv murine leukemia virus-based vectors involving initial priming on endogenous viral sequences and template switching during cDNA synthesis to obtain PBS complementarity in second-strand transfer of reverse transcription (Mikkelsen et al., J. Virol. 70:1439–1447, 1996). By use of the same forced recombination system, we have now found recombinant proviruses of different structures, suggesting that PBS knockout vectors may be rescued through initial priming on endogenous virus RNA, read-through of the mutated PBS during minus-strand synthesis, and subsequent second-strand transfer mediated by the R-U5 complementarity of the plus strand and the extended minus-strand DNA acceptor template. Mechanisms for R-U5-mediated second-strand transfer and its possible role in retrovirus replication and evolution are discussed.

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Bacinschi, Nicolae, Sofia Alexandru, Anna Donica et Ina Guţu. « Directions for research and development of anti-tuberculosis drugs ». Farmacist.ro 5, n^o 1 (30 octobre 2019) : 28–36. http://dx.doi.org/10.26416/farm.190.5.2019.2632.

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The increasing incidence of new cases of tuberculosis, of latent forms and with multiple and extended resistance, required the acceleration of the research and elaboration of the anti-tuberculosis drugs by elucidating new targets. The main directions of study of the new compounds focused on the influence on the cell wall, the synthesis of proteins and nucleic acids, the energy metabolism, as well as on the immune status of the host. At the base of these strategies were the data regarding the structural components and the particularities of the life cycle of mycobacteria at different stages of disease evolution.

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Vasileva, Anna A., Daria V. Mamonova, Yuri V. Petrov, Ilya E. Kolesnikov, Gerd Leuchs et Alina A. Manshina. « Laser-Induced Synthesis of Electrocatalytically Active Ag, Pt, and AgPt/Polyaniline Nanocomposites for Hydrogen Evolution Reactions ». Nanomaterials 13, n^o 1 (24 décembre 2022) : 88. http://dx.doi.org/10.3390/nano13010088.

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We present an efficient and easily implemented approach for creating stable electrocatalytically active nanocomposites based on polyaniline (PANI) with metal NPs. The approach combines in situ synthesis of polyaniline followed by laser-induced deposition (LID) of Ag, Pt, and AgPt NPs. The observed peculiarity of LID of PANI is the role of the substrate during the formation of multi-metallic nanoparticles (MNP). This allows us to solve the problem of losing catalytically active particles from the electrode’s surface in electrochemical use. The synthesized PANI/Ag, PANI/Pt, and PANI/AgPt composites were studied with different techniques, such as SEM, EDX, Raman spectroscopy, and XPS. These suggested a mechanism for the formation of MNP on PANI. The MNP–PANI interaction was demonstrated, and the functionality of the nanocomposites was studied through the electrocatalysis of the hydrogen evolution reaction. The PANI/AgPt nanocomposites demonstrated both the best activity and the most stable metal component in this process. The suggested approach can be considered as universal, since it can be extended to the creation of electrocatalytically active nanocomposites with various mono- and multi-metallic NPs.

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LU, PAI, et DONGFENG XUE. « GROWTH OF ONE-DIMENSIONAL MnO2 NANOSTRUCTURE ». Modern Physics Letters B 23, n^o 31n32 (30 décembre 2009) : 3835–41. http://dx.doi.org/10.1142/s0217984909021892.

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Large scale MnO 2 nanorods were controllably synthesized from the inexpensive precursors (e.g., manganese acetate, ammonium persulfate) via a facile one-step low temperature hydrothermal strategy. The crystal phase and microscopic morphology of the as-prepared MnO 2 nanorods were characterized by X-ray powder diffraction (XRD) and scanning electron microscope (SEM). Through investigating the morphology evolution of MnO 2 products in the whole synthesis process, a novel growth mechanism of these MnO 2 nanorods was proposed, which may be efficiently extended to other material systems as a general approach towards one-dimensional nanostructures. The obtained MnO 2 nanorods may have potential applications in Li -ion batteries and supercapacitors.

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Hartman, J. W., F. Verbunt, D. Bhattacharya et R. Wijers. « The Case for no field decay from improved pulsar population studies ». International Astronomical Union Colloquium 160 (1996) : 47–48. http://dx.doi.org/10.1017/s0252921100040987.

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We perform radio pulsar population synthesis to study the evolution of the pulsar population. In doing this, we continue our earlier work on this subject (Bhattacharya et al. 1992). We have extended our work by 1) calculating orbits in the whole galaxy (the simulation of the observations however is still limited to the solar neighborhood), 2) using the high birth velocities of radio pulsars from Lyne & Lorimer (1994) and 3) implementing the new model by Taylor & Cordes (1993) of the distribution of free electrons in the galaxy. A full report of this work will be given in Hartman et al. (1996).

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Clarizia, Laura, Giuseppe Vitiello, Robert Bericat Vadell, Jacinto Sá, Raffaele Marotta, Ilaria Di Somma, Roberto Andreozzi et Giuseppina Luciani. « Effect of Synthesis Method on Reaction Mechanism for Hydrogen Evolution over CuxOy/TiO2 Photocatalysts : A Kinetic Analysis ». International Journal of Molecular Sciences 24, n^o 3 (19 janvier 2023) : 2004. http://dx.doi.org/10.3390/ijms24032004.

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The existing literature survey reports rare and conflicting studies on the effect of the preparation method of metal-based semiconductor photocatalysts on structural/morphological features, electronic properties, and kinetics regulating the photocatalytic H2 generation reaction. In this investigation, we compare the different copper/titania-based photocatalysts for H2 generation synthesized via distinct methods (i.e., photodeposition and impregnation). Our study aims to establish a stringent correlation between physicochemical/electronic properties and photocatalytic performances for H2 generation based on material characterization and kinetic modeling of the experimental outcomes. Estimating unknown kinetic parameters, such as charge recombination rate and quantum yield, suggests a mechanism regulating charge carrier lifetime depending on copper distribution on the TiO2 surface. We demonstrate that H2 generation photoefficiency recorded over impregnated CuxOy/TiO2 is related to an even distribution of Cu(0)/Cu(I) on TiO2, and the formation of an Ohmic junction concertedly extended charge carrier lifetime and separation. The outcomes of the kinetic analysis and the related modeling investigation underpin photocatalyst physicochemical and electronic properties. Overall, the present study lays the groundwork for the future design of metal-based semiconductor photocatalysts with high photoefficiencies for H2 evolution.

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Gagen, Emma J., Marcos Y. Yoshinaga, Franka Garcia Prado, Kai-Uwe Hinrichs et Michael Thomm. « The Proteome and Lipidome ofThermococcus kodakarensisacross the Stationary Phase ». Archaea 2016 (2016) : 1–15. http://dx.doi.org/10.1155/2016/5938289.

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The majority of cells in nature probably exist in a stationary-phase-like state, due to nutrient limitation in most environments. Studies on bacteria and yeast reveal morphological and physiological changes throughout the stationary phase, which lead to an increased ability to survive prolonged nutrient limitation. However, there is little information on archaeal stationary phase responses. We investigated protein- and lipid-level changes inThermococcus kodakarensiswith extended time in the stationary phase. Adaptations to time in stationary phase included increased proportion of membrane lipids with a tetraether backbone, synthesis of proteins that ensure translational fidelity, specific regulation of ABC transporters (upregulation of some, downregulation of others), and upregulation of proteins involved in coenzyme production. Given that the biological mechanism of tetraether synthesis is unknown, we also considered whether any of the protein-level changes inT. kodakarensismight shed light on the production of tetraether lipids across the same period. A putative carbon-nitrogen hydrolase, a TldE (a protease inEscherichia coli) homologue, and a membrane bound hydrogenase complex subunit were candidates for possible involvement in tetraether-related reactions, while upregulation of adenosylcobalamin synthesis proteins might lend support to a possible radical mechanism as a trigger for tetraether synthesis.

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Thorkelson, Derek J., J. Grant Abbott, James K. Mortensen, Robert A. Creaser, Michael E. Villeneuve, Vicki J. McNicoll et Paul W. Layer. « Early and Middle Proterozoic evolution of Yukon, Canada ». Canadian Journal of Earth Sciences 42, n^o 6 (1 juin 2005) : 1045–71. http://dx.doi.org/10.1139/e04-075.

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This paper provides a comprehensive synthesis of virtually all units and events of Early and Middle Proterozoic age in the Yukon, spanning ~1 Ga. Early and Middle Proterozoic time was dominated by a series of extensional-basin-forming events punctuated by orogenesis, magmatism, and hydrothermal activity. Basinal deposits include the Wernecke Supergroup (>1.71 Ga), Pinguicula Group (~1.38 Ga), and Mackenzie Mountains Supergroup (1.000.78 Ga). Igneous rocks include the Bonnet Plume River Intrusions (1.71 Ga), Slab volcanics (≥1.6 Ga), Hart River sills and volcanics (1.38 Ga), and Bear River (Mackenzie) dykes (1.27 Ga). A voluminous hydrothermal event generated the widespread Wernecke breccias at 1.60 Ga. The Racklan orogeny deformed the Wernecke Supergroup prior to emplacement of the Wernecke Breccia. The Corn Creek orogeny deformed Mackenzie Mountains Supergroup and older rocks prior to deposition of the Windermere Supergroup (<0.78 Ga). Long intervals with scanty rock records extended for as much as 300 Ma and appear to represent periods of crustal stability and subaerial conditions. By the time of Windermere rifting (<0.78 Ga), the supracrust of northwestern Laurentia was a mature, largely denuded orogenic belt with a composite sedimentarymetamorphicigneous character. New isotopic data include Nd depleted mantle model ages for the Wernecke Supergroup (2.282.69 Ga) and Wernecke Breccia (2.362.96 Ga), a UPb zircon age for a Hart River sill 1381.9+5.3-3.7 (Ma), detrital UPb zircon ages from the basal Pinguicula Group (18413078 Ma), detrital muscovite ages from the Mackenzie Mountains Supergroup (10372473 Ma), and muscovite 40Ar/39Ar cooling ages from the Wernecke Supergroup (788 ± 8 and 980 ± 4 Ma).

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Sprenger, Paul, Thomas Sheppard, Jussi-Petteri Suuronen, Abhijeet Gaur, Federico Benzi et Jan-Dierk Grunwaldt. « Structural Evolution of Highly Active Multicomponent Catalysts for Selective Propylene Oxidation ». Catalysts 8, n^o 9 (27 août 2018) : 356. http://dx.doi.org/10.3390/catal8090356.

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Multicomponent Bi-Mo-Fe-Co oxide catalysts prepared via flame spray pyrolysis were tested for selective propylene oxidation, showing high conversion (>70%) and selectivity (>85%) for acrolein and acrylic acid at temperatures of 330 °C. During extended time-on-stream tests (5–7 days), the catalysts retained high activity while undergoing diverse structural changes. This was evident on: (a) the atomic scale, using powder X-ray diffraction, Raman spectroscopy, X-ray absorption spectroscopy, X-ray photoelectron spectroscopy, and transmission electron microscopy; and (b) the microscopic scale, using synchrotron X-ray nanotomography, including full-field holotomography, scanning X-ray fluorescence, and absorption contrast imaging. On the atomic scale, sintering, coke formation, growth, and transformation of active and spectator components were observed. On the microscopic scale, the catalyst life cycle was studied at various stages through noninvasive imaging of a ~50-µm grain with 100-nm resolution. Variation of catalyst synthesis parameters led to the formation of notably different structural compositions after reaction. Mobile bismuth species formed agglomerates of several hundred nanometres and segregated within the catalyst interior. This appeared to facilitate the formation of different active phases and induce selectivity for acrolein and acrylic acid. The combined multiscale approach here is generally applicable for deconvolution of complex catalyst systems. This is an important step to bridge model two-component catalysts with more relevant but complex multicomponent catalysts.

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Van Bever, Joris, et Dany Vanbeveren. « The impact of close binary evolution on the properties of the WR-bump emission lines of Wolf-Rayet galaxies ». Symposium - International Astronomical Union 212 (2003) : 576–77. http://dx.doi.org/10.1017/s007418090021293x.

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We present the results of a study on the behaviour of the blue and red WR emission bumps (around 4650Å and 5808Å) and of the nebular contribution to He ii λ4686 in evolving young starburst regions (such as Wolf-Rayet galaxies), containing a non-negligible binary population. Calculations were made for solar metallicity and 1/20 solar. The population synthesis program uses an extended library of stellar evolutionary tracks of single stars and binaries, computed using the most recent stellar wind mass loss rates during RSG, LBV and WR stages. In the case of binaries, we account in detail for the effects of Roche lobe overflow, mass transfer and mass accretion, common envelope evolution, the spiral-in process, asymmetric kicks to neutron stars as a result of their supernova explosion, etc. This research is part of a more extensive project to explore every possible impact of massive binaries on stellar populations.

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Chelaru, Teodor Viorel, Valentin Pana et Adrian Chelaru. « Longitudinal Control System Design Using Gradient Method for a Suborbital Launcher ». Applied Mechanics and Materials 555 (juin 2014) : 113–20. http://dx.doi.org/10.4028/www.scientific.net/amm.555.113.

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The aim of this paper is to present a design method for the guidance navigation and control system (GNC) of a suborbital launcher. In order to achieve a symmetric evolution in the vertical plane we start with the decoupled form of the equation of motion. Afterwards these equations are linearized and the extended stability and command matrices are constructed by adding some auxiliary equations. The linear control law is obtained and the control matrix containing the unknown coefficients is presented. The design of the control system is based on a modified gradient method. To illustrate the proposed method the synthesis of the control system in the specific case of the SLT ("Suborbital Launcher for Testing - SLT" financed thru „Programme for Research-Development-Innovation on Space Technology and Advanced Research – STAR”) is presented.

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Zheng, Weijia, Runquan Huang, Ying Luo, YangQuan Chen, Xiaohong Wang et Yong Chen. « A Look-Up Table Based Fractional Order Composite Controller Synthesis Method for the PMSM Speed Servo System ». Fractal and Fractional 6, n^o 1 (15 janvier 2022) : 47. http://dx.doi.org/10.3390/fractalfract6010047.

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Considering the performance requirements in actual applications, a look-up table based fractional order composite control scheme for the permanent magnet synchronous motor speed servo system is proposed. Firstly, an extended state observer based compensation scheme was adopted to suppress the motor parametric uncertainties and convert the speed servo plant into a double-integrator model. Then, a fractional order proportional-derivative (PDμ) controller was adopted as the speed controller to provide the optimal step response performance for the servo system. A universal look-up table was established to estimate the derivative order of the PDμ controller, according to the optimal samples collected by an improved differential evolution algorithm. With the look-up table, the optimal PDμ controller can be tuned analytically. Simulation and experimental results show that the servo system using the composite control scheme can achieve optimal tracking performance and has robustness to the motor parametric uncertainties and disturbance torques.

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Md Dipu Ahmed, Kazi M Maraz, Shahirin Shahida, Tarannum Dihan et Ruhul A Khan. « A review on the synthesis, surface modification and drug delivery of nanoparticles ». Global Journal of Engineering and Technology Advances 8, n^o 2 (30 août 2021) : 032–45. http://dx.doi.org/10.30574/gjeta.2021.8.2.0114.

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Over the past few years, the evolution of nanotechnology has extended into a wide range of applications. Nanotechnology has now become a multidisciplinary science that applies to electronics, materials science, biomedical engineering, microbiology, etc. Recently, nanotechnology is being used in biomedical and pharmaceutical science. Among them drug delivery is set to spread rapidly. Application of nanotechnology in health sector also created a potential impact such as in the fields of immunology, cardiology, endocrinology, ophthalmology, and oncology. Nanoparticles are unique because of their large surface area and it has the potential to change the properties of a bulk number of materials. The surface of nanoparticles can be modified with the help of various polymers, organic and inorganic substances according to the specific application and their use. Nanoparticles are also utilized as nano shells in drug delivery systems and cancer therapy. Nano shells can recognize the cancer cells when they are injected into the cancer area. The heat generated by the light absorbing nano shells due to the application of the near infrared light successfully kills tumour cells leaving the noncarcinogenic cells intact. In this review article, nanoparticles, the health implication of nanoparticles and their synthesis are discussed.

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Arianpour, F., F. Kazemi, Hamid Reza Rezaie, A. Asjodi et J. Liu. « Nanozirconium Carbide Powder Synthesis via Carbothermal Route ». Defect and Diffusion Forum 334-335 (février 2013) : 381–86. http://dx.doi.org/10.4028/www.scientific.net/ddf.334-335.381.

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Zirconium carbide (ZrC) has extended application in many ceramic and metal matrix composites especially used for ultra high temperature conditions. The synthesis of zirconium carbide powder is costly and difficult because of its high refractoriness and chemically inert properties. In this research, the synthesis of zirconium carbide nanopowder at low temperature via carbothermal reduction route was investigated according to thermodynamic data. The starting materials were zirconium acetate and sucrose as zirconium and carbon sources, respectively. After preparation of different carbon/zirconium ratio containing precursors, the dried precursors were heat treated at 1400°C and vacuum atmosphere. Also the ZrC formation was followed by thermal analysis of the produced precursors. The phase evolutions and microstructural studies were carried out using X-ray diffraction and scanning electron microscopy. The results showed that it is possible to synthesis zirconium carbide nanopowder with round shape and crystallite sizes smaller than 20 nm at low temperatures. Also according to thermodynamic calculations, it was concluded that by applying vacuum condition, the zirconium carbide formation can occur at less than 1000°C which is very effective on the size reducing of produced ZrC nanopowders.

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De Loof, Arnold. « Organic and Cultural Evolution can be Seamlessly Integrated Using the Principles of Communication and Problem-Solving : The Foundations for an Extended Evolutionary Synthesis (EES) as Outlined in the Mega-Evolution Concept ». Life : The Excitement of Biology 2, n^o 4 (10 janvier 2015) : 247–69. http://dx.doi.org/10.9784/leb2(4)deloof.01.

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Hamers, Adrian S., Hila Glanz et Patrick Neunteufel. « A Statistical View of the Stable and Unstable Roche Lobe Overflow of a Tertiary Star onto the Inner Binary in Triple Systems ». Astrophysical Journal Supplement Series 259, n^o 1 (1 mars 2022) : 25. http://dx.doi.org/10.3847/1538-4365/ac49e7.

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Abstract In compact stellar triple systems, an evolved tertiary star can overflow its Roche lobe around the inner binary. Subsequently, the tertiary star can transfer mass to the inner binary in a stable manner, or Roche lobe overflow (RLOF) can be unstable and lead to common-envelope (CE) evolution. In the latter case, the inner binary enters the extended envelope of the tertiary star and spirals in toward the donor’s core, potentially leading to mergers or ejections. Although studied in detail for individual systems, a comprehensive statistical view on the various outcomes of triple RLOF is lacking. Here, we carry out 105 population synthesis simulations of tight triples, self-consistently taking into account stellar evolution, binary interactions, and gravitational dynamics. Also included are prescriptions for the long-term evolution of stable triple mass transfer, and triple CE evolution. Although simple and ignoring hydrodynamic effects, these prescriptions allow for a qualitative statistical study. We find that triple RLOF occurs in ∼0.06% of all triple systems. Of these 0.06%, ∼64% of cases lead to stable mass transfer, and ∼36% to triple CE evolution. Triple CE is most often (∼76%) followed by one or multiple mergers in short succession, most likely an inner binary merger of two main-sequence stars. Other outcomes of triple CE are a binary+single system (∼23%, most of which do not involve exchange interactions), and a stable triple (∼1%). We also estimate the rate of type Ia supernovae involving white dwarf mergers following triple RLOF, but find only a negligible contribution.

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Zhang, Jiahang, Zhiwei Zhang, Wen Liu, Lijing Li, Liebao Han, Lixin Xu et Yuhong Zhao. « Transcriptome Analysis Revealed a Positive Role of Ethephon on Chlorophyll Metabolism of Zoysia japonica under Cold Stress ». Plants 11, n^o 3 (5 février 2022) : 442. http://dx.doi.org/10.3390/plants11030442.

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Zoysia japonica is a warm-season turfgrass with a good tolerance and minimal maintenance requirements. However, its use in Northern China is limited due to massive chlorophyll loss in early fall, which is the main factor affecting its distribution and utilization. Although ethephon treatment at specific concentrations has reportedly improved stress tolerance and extended the green period in turfgrass, the potential mechanisms underlying this effect are not clear. In this study, we evaluated and analyzed chlorophyll changes in the physiology and transcriptome of Z. japonica plants in response to cold stress (4 °C) with and without ethephon pretreatment. Based on the transcriptome and chlorophyll content analysis, ethephon pretreatment increased the leaf chlorophyll content under cold stress by affecting two processes: the stimulation of chlorophyll synthesis by upregulating ZjMgCH2 and ZjMgCH3 expression; and the suppression of chlorophyll degradation by downregulating ZjPAO, ZjRCCR, and ZjSGR expression. Furthermore, ethephon pretreatment increased the ratio of chlorophyll a to chlorophyll b in the leaves under cold stress, most likely by suppressing the conversion of chlorophyll a to chlorophyll b due to decreased chlorophyll b synthesis via downregulation of ZjCAO. Additionally, the inhibition of chlorophyll b synthesis may result in energy redistribution between photosystem II and photosystem I.

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Belkus, Houria, Joris Van Bever, Dany Vanbeveren et Walter van Rensbergen. « Synthetic UV spectra of starburst regions with massive close binaries ». Symposium - International Astronomical Union 212 (2003) : 539–40. http://dx.doi.org/10.1017/s0074180900212758.

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We present the evolution of synthetic ultraviolet spectra of starburst regions having a significant fraction of binaries. The population synthesis program uses an extended library of stellar evolutionary tracks of single stars and binaries computed with the most recent stellar wind mass loss rates during RSG, LBV and WR stages. In the case of binaries we account in detail for the effects of Roche lobe overflow, mass transfer and mass accretion, common envelope evolution, the spiral-in process, asymmetric kicks to neutron stars as a result of their supernova explosion, etc. The most important synthesized line profiles are those of Si iv λ1400 and C iv λ1550, two P-Cygni lines prominent in O-type stars. The main effect of the close binaries is to extend the UV bright lifetime of the starburst due to the appearance of accretion stars. But more importantly, our computations show that a spectrum of a single star model of about 6 Myr old is effectively undistinguishable from that of a binary rich model of about 10 Myr old. This indicates a possible age degeneracy, reminiscent of the influence of binaries on the commonly used optical age indicator WHβ.

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Nivetha, Ravi, Sushant Sharma, Jayasmita Jana, Jin Suk Chung, Won Mook Choi et Seung Hyun Hur. « Recent Advances and New Challenges : Two-Dimensional Metal–Organic Framework and Their Composites/Derivatives for Electrochemical Energy Conversion and Storage ». International Journal of Energy Research 2023 (13 février 2023) : 1–47. http://dx.doi.org/10.1155/2023/8711034.

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Metal–organic frameworks (MOFs), as a new generation of intrinsically porous extended crystalline materials formed by coordination bonding between the organic ligands and metal ions or clusters, have attracted considerable interest in many applications owing to their high porosity, diverse structures, and controllable chemical structure. Recently, 2D transition-metal- (TM-) based MOFs have become a hot topic in this field because of their high aspect ratio derived from their large lateral size and small thickness, as well as the advantages of MOFs. Moreover, 2D TM-based MOFs can act as good precursors to construct heterostructures with high electrical conductivity and abundant active sites for a range of applications. This review comprehensively introduces the widely adopted synthesis strategies of 2D TM-based MOFs and their composites/derivatives. In addition, this paper summarizes and highlights the recent advances in energy conversion and storage, including the hydrogen evolution reaction, oxygen evolution reaction, oxygen reduction reaction, CO2 reduction reaction, urea oxidation reaction, batteries, and supercapacitors. Finally, the challenges in developing these intriguing 2D layered materials and their composites/derivatives are examined, and the possible proposals for future directions to enhance the energy conversion and storage performance are reviewed.

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Gera, Rajat, Priyanka Chadha et Shirin Alavi. « A Comprehensive Synthesis of Theories of Mobile Shopping Adoption and Narrative Review ». International Journal of Cyber Behavior, Psychology and Learning 11, n^o 2 (avril 2021) : 52–74. http://dx.doi.org/10.4018/ijcbpl.2021040104.

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This paper aims to synthesize and integrate the existing literature on MSA adoption and provide directions for future research through narrative review by classifying and organizing the accumulated knowledge into a thematic framework. The paper's theoretical, conceptual approaches, and results were organized into three themes: online distribution channel (theoretical approaches and antecedent factors of MSA adoption, consumer characteristics), advanced technology for in-store shopping (marketing aspects of MSA), and technology perspectives (technology aspects of MSA). The 25 theories of mobile shopping app (MSA) adoption and usage (at the individual level) from 22 reviewed papers were summarized, defined, and mapped with authors. Research questions have been proposed for theories used in reviewed papers and new theories. MSA adoption is at an emergent stage of evolution with fragmentation of theoretical and methodological approaches. While theories of technology adoption and behavioral intentions have been used predominantly, most studies have adopted a multi-theoretic approach or have extended/modified the model with hedonic, situational, and behavioral constructs. The findings related to consumer characteristics of MSA adoption, anchor constructs, moderator and mediator variables, and marketing and technology features of MSA are synthesized and organized according to the themes. Theoretical and practical implications are drawn, research limitations are identified, and future research directions are suggested.

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