bluuebunny/crossref_metadata_2025 huggingface dataset:
Discourse analysis of online product reviews: A discussion of digital consumerism and culture
Authors: Park Haseon , Lee Joonghwa
Published: May 2019

This study focuses on consumer interaction via online product reviews in digital markets by incorporating intercultural perspective. In doing so, this study explores the representation of digital consumerism, defined as development of consumer empowerment and vulnerability in digital markets, which appears as a paradigm to ensure balanced market environments for both consumers and companies (Kucuk, 2016). In particular, this study investigates cultural differences in the representation of digital consumerism in online product reviews by comparing the online product reviews from U.S. and South Korea. Additionally, message strategies employed in the online product reviews were also examined in respect of digital consumerism while comparing the two cultures. A discourse analysis on a total of 400 online product reviews (i.e., 200 from U.S., 200 from South Korea) was conducted to understand how digital consumerism can be constructed. The results indicated significant cultural differences between the U.S. and South Korea based on online consumer powers manifested in the content of online product reviews as well as message strategies adopted to express digital consumerism. In the U.S., economic, technologic, and social power were more frequently observed in online product reviews compared to legal power; In contrast, in South Korea, economic power was the most frequently observed, followed by social and technologic power. In terms of message strategies, transformational messages were dominantly used to express digital consumerism in online product reviews from both countries, whereas each type of online consumer powers was expressed differently in the U.S. and South Korea by adopting different message strategies. Theoretical and practical implications are discussed.
Armchair Philosophy
Authors: Williamson Timothy ,   Institute of Philosophy, Russian Academy of Sciences
Published: May 2019

The article presents an anti-exceptionalist view of philosophical methodology, on which it is much closer to the methodology of other disciplines than many philosophers like to think. Like mathematics, it is a science, but not a natural science. Its methods are notprimarily experimental, though it can draw on the results of natural science. Likefoundational mathematics, its methods are abductive as well as deductive. As in the natural sciences, much progress in philosophy consists in the construction of better models rather than in the discovery of new laws. We should not worry about whether philosophy is a priori or a posteriori, because the distinction is epistemologically superficial.
Philosophy or Auto-Anthropology?
Authors: Dennett Daniel C. ,   Institute of Philosophy, Russian Academy of Sciences
Published: May 2019

Timothy Williamson is mainly right, I think. He defends armchair philosophy as a variety of armchair science, like mathematics, or computer modeling in evolutionary theory, economics, statistics, and I agree that this is precisely what philosophy is, at its best: working out the assumptions and implications of any serious body of thought, helping everyone formulate the best questions to ask, and then leaving the empirical work to the other sciences. Philosophy – at its best – is to other inquiries roughly as theoretical physics is to experimental physics. You can do it in the armchair, but you need to know a lot about the phenomena with which the inquiry deals.
Armchair Science and Armchair Philosophy
Authors: Kuznetsov Anton V. ,   Institute of Philosophy, Russian Academy of Sciences
Published: May 2019

Williamson defends armchair philosophy by likening it to armchair science – they have the same echelon of results and use such a priori methods as model building and conditional analyses. More, if a priori methods are accepted within science, then they acceptable in philosophy – thus, armchair philosophy is justified. However, I am not swayed by this reasoning: there could be non-armchair philosophers who use these a priori methods. So, there are two options – revise the notion of armchair philosophy or add more details to the aforementioned reasoning.
Afterword to the Panel Discussion on Armchair Philosophy
Authors: Vasilyev Vadim V. ,   Institute of Philosophy, Russian Academy of Sciences
Published: May 2019

In this paper I discuss Timothy Williamson’s panel paper “Armchair Philosophy”, the objections of the participants of the panel discussion and other possible reactions to it. The correspondence of the content of Williamson’s paper to the main themes of his book “Doing Philosophy” is shown, as well as the greater emphasis of his paper on the method of model building, upon which he bases his hope for the future of armchair philosophy. The analysis of the responses to the paper by Williamson received from Daniel Stoljar, Joshua Knobe, Daniel Dennett, and Anton Kuznetsov shows, however, that the version of the armchair philosophy proposed by Williamson does not raise much objections among principal opponents of the armchair approach and thus does not promote an a priori methodology that this kind of philosophy is supposed to defend and promote. More effective defense would require the use of a conceptual analysis that promises getting a priori or conceptual truths. Williamson, however, doubts the prospects for productive conceptual analysis. Nevertheless, the author of this afterword tries to show that the traditional conceptual analysis can be improved and that it is possible that such an improved analysis would perform its function of promoting the radical armchair philosophy much more effectively. Instead of clarifying some more or less interesting concepts conceptual analysis might aim at clarifying our natural beliefs, such as belief in causal dependance of ordinary events, in independent existence of the objects of our experience, in identity of some objects, in other minds, etc. In the process of such a clarifying we can also try to understand some non-trivial relations between our natural beliefs. The author provides an example of such an analysis, resulting in getting a truth which has all the marks of necessary conceptual truth, claiming there are a lot of similar truths to be found.
The Argument from Variation against Using One’s Own Intuitions as Evidence
Authors: Goh Esther ,   Institute of Philosophy, Russian Academy of Sciences
Published: May 2019

In philosophical methodology, intuitions are used as evidence to support philosophical theories. In this paper, I evaluate the skeptical argument that variation in intuitions is good evidence that our intuitions are unreliable, and so we should be skeptical about our theories. I argue that the skeptical argument is false. First, variation only shows that at least one disputant is wrong in the dispute, but each disputant lacks reason to determine who is wrong. Second, even though variation in intuitions shows that at least one disputant has the wrong intuition in the thought experiment, it is not evidence of unreliability of any disputant’s intuition regarding the philosophical theory being tested. So, variation in intuitions is not good evidence that one’s own intuitions are unreliable. One reply from the literature in peer disagreement is that we should conciliate if we cannot determine who is wrong. I argue that these disagreements are instead unconfirmed peer disagreements (i.e., no good reason to take or dismiss disputants as an epistemic peer, inferior or superior). I argue that if you have a strong intuition about a case, then it is rational for you to remain steadfast. Thus, variation in intuitions does not call for skepticism.
Problems of Metaphilosophy – a View from Aside
Authors: Nikiforov Alexander L. ,   Institute of Philosophy, Russian Academy of Sciences
Published: May 2019

The paper discusses several problems of metaphilosophy that were explored in the philosophical literature in Russia. Metaphilosophy tries to understand what is philosophy, what problems philosophers are dealing with, which methods they employ in their investigations, the nature of philosophical statements and so on. Philosophers in Russia tended to think of philosophy as a special type of worldview that exists together with the ordinary worldview and religious worldview. The author defines worldview as a collection of basic beliefs about the surrounding world, society, human being, the relations existing between individuals and society, about values and ideals. It is underscored that a worldview is always somebody’s worldview (it belongs either to an individual or a social group). The worldview problems explored by philosophers remain the same throughout thousands of years; what changes is how they are stated in different times. Every human being faces these problems if she has realized herself as an autonomous being and the reality splits for her into the I and the non-I. All philosophical problems revolve around three basic questions: what is the non-I (i.e. nature and society)? - this is the ontological question; what is I? (the anthropological question); what relations exist between the I and the non-I (the epistemological, axiological, ethical and other questions). The author also explores several stages of a philosophical investigation: an internal dissatisfaction with existing solutions, a search for a new perspective (meaning, idea, interpretation), development of the found solution. The author points at a number of characteristics that make philosophy different from science: philosophical statements and conceptions cannot be verified or refuted by experience, they are not universal. It is argued that the notion of truth in its classical interpretation cannot be applied to philosophical statements because the latter cannot be true or false. The author concludes that philosophical statements or conceptions express the subjective opinion of a given philosopher about the world and the human being. An obvious evidence for this is the existing pluralism of philosophical systems, schools, and trends.
Normative Ethics: an Armchair Discipline?
Authors: Pedersen Johnnie R.R. ,   Institute of Philosophy, Russian Academy of Sciences
Published: May 2019

This paper discusses a challenge to normative ethics motivated by experimental philosophy. Experimental philosophers object to the perceived “armchair” or a priori nature of philosophy, claiming it should rather be empirical or naturalistic. The paper investigates the application of this claim to normative ethics. Dubbing the application of the experimental philosophers’ contention to normative ethics “the Armchair Claim,” I distinguish descriptive and normative versions of this challenge, and consider their merits as comments on the method of normative ethics (descriptive versions), and as comments on how normative ethics should be done (normative versions). Characterizing normative ethics as essentially involving the use of the method of reflective equilibrium, I show how the versions of the Armchair Claim that I distinguish either misconstrue normative ethics, or are committed to metaethical views that are controversial. To bring home the latter point, I contrast two meta-ethical positions, and show how, on one such view, naturalism, the descriptive version could be correct, whereas on another, intuitionism, it would be false. The normative version, in turn, is consistent with naturalism, but begs the question against the intuitionist since she argues that normative ethics cannot be empirical. The upshot is that a conclusive assessment of the Armchair Claim will have to await the resolution of disputed issues in meta-ethics. However, normative ethicists can get on with their work since reflective equilibrium is unaffected by such debates.
McTaggart: Reality in Idealism
Authors: Veretennikov Andrey A. ,   Institute of Philosophy, Russian Academy of Sciences
Published: May 2019

Article is dedicated to the description and analysis of metaphilosophical and scientific contexts of the McTaggart paper ‘The Unreality of Time’ (1908) and drawing connections to the ‘analytical’ style of his pupils – B. Russell and G.E. Moore. Main line of argument against the reality of time is presented and analyzed. By the positive relation of McTaggart to the work on ethics by G.E. Moore and negative – to philosophical implications of the special theory of relativity author shows the movement for the autonomy of philosophy or ‘antipsychologism’. Question of a different understanding of the term ‘reality’ in Moore and McTaggart is posed and resolved.
Normativity, Expertise and Epistemological Paternalism in the Philosophy of Science
Authors: Kostina Alina O. ,   Institute of Philosophy, Russian Academy of Sciences
Published: May 2019

For almost 50 years the journal Metaphilosophy has been publishing research on a wide range of philosophical issues from the fundamental questions of ontology, epistemology and the philosophy of science to applied studies on ethics, technology and STS. The following review focuses on a number of key questions that have become the stumbling block for investigations in epistemology, philosophy and methodology of science and STS. The spotlight here is on the issues of reestablishment of normativity in philosophy of science, related to the PSP turn; new perspectives on the “armchair philosophy” and the ex cathedra principle; the misuse of scientific data by the philosophers of science; experimental philosophy and the “undermined” authority of philosophical expertise; and also we’ll find out how epistemic paternalism may become a virtue of research practice.
Levantamiento de metales pesados en el agua subterránea de la subcuenca del rio Estrela, Saracuruna, Rio de Janeiro
Authors: Silva Cleber Vinicius Vitorio , Almeida Josimar Ribeiro de , Silva Carlos Eduardo , Carvalho Lyanna Oliveira de
Published: May 2019

Los niveles de compuestos xenobióticos volcados en los ambientes acuáticos, han aumentado de forma alarmante como resultado de la actividad antropogénica sobre el medio ambiente. Los metales pesados se diferencian de otros compuestos tóxicos por ser absolutamente no degradables, pudiendo acumularse en los componentes del ambiente, como las aguas subterráneas de una región, donde poseen sus concentraciones naturales aumentadas, debido a las actividades antrópicas en los ecosistemas, las aguas subterráneas de regiones en las ciudades, industrias, carreteras, emprendimientos inmobiliarios, garimpos, basurales y viviendas humanas presentan diversas alteraciones en cuanto a las concentraciones permitidas por ley para metales pesados. Para esta realidad ambiental deletérea, la subcuenca del río Estrela, ubicada en el municipio de Duque de Caxias-RJ, tiene uno largo histórico de contaminación por metales pesados, frente a las actividades antrópicas sobre la región. Gran parte de la población local utiliza las aguas subterráneas de la región para consumo humano, animal y en actividades agrícolas, con eso se realizó el sondaje de las aguas subterráneas para evaluar su toxicidad en cuanto a la concentración de metales pesados en referencia a la Resolución No 420/2009 del Consejo Nacional del Medio Ambiente (CONAMA). Para los 18 metales (Aluminio, Arsén, Bario, Boro, Cadmio, Plomo, Cobalto, Cobre, Cromo, Hierro, Manganeso, Molibdeno, Níquel, Selenio, Zinc, Antimonio, Mercurio y Plata) analizados, para un de lineamento muestral de 5 puntos en la subcuenca del río Estrela, se constata una alta concentración de 15 metales potencialmente peligrosos a la salud humana y el bienestar animal y vegetal.
Un análisis de la eficiencia de municipios turísticos españoles
Authors: Bendodo Benasayag Elías , Fernández Gámez Manuel Ángel , Sánchez Serrano José Ramón
Published: May 2019

El objetivo de este estudio es conocer qué factores exógenos condicionan la eficiencia de los municipios con una marcada orientación turística. Este estudio es una de las pocas publicaciones basadas en la eficiencia de municipios turísticos. A diferencia de la mayoría de las investigaciones que evalúan la eficiencia municipal en general, se cree que este documento contribuye a la literatura relacionada ofreciendo ideas a los municipios turísticos relativamente ineficientes sobre la mejora de la eficiencia.

The objective of this study is to know which exogenous factors condition the efficiency of the municipalities with tourist orientation. This study is one of the few publications based on the efficiency of tourism municipalities. Unlike most of the research that assesses municipal efficiency in general, it is believed that this document contributes to related literature by offering ideas to relatively inefficient tourism municipalities about improving efficiency.
Indispensability and Effectiveness of Diagrams in Molecular Biology
Authors: Anta Javier
Published: May 2019

Abstract: In this paper I aim to defend a twofold thesis. On one hand, I will support, against Perini (2005), the indispensability of diagrams when structurally complex biomolecules are concerned, since it is not possible to satisfactorily use linguistic-sentential representations at that domain. On the other hand, even when diagrams are dispensable I will defend than they will generally be more effective than other representations in encoding biomolecular knowledge, relying on Kulvicki-Shimojima’s diagrammatic effectiveness thesis. Finally, I will ground many epistemic virtues of biomolecular diagrams (understandability, explanatory power, prediction and hypothesis evaluation) on their cognitive-computational indispensability and their semantic-epistemic effectiveness.
Keywords: Molecular Biology, Diagrammatic Representation, Representational Indispensability.
Local online learning in recurrent networks with random feedback
Authors: Murray James M
Published: May 2019

Recurrent neural networks (RNNs) enable the production and processing of time-dependent signals such as those involved in movement or working memory. Classic gradient-based algorithms for training RNNs have been available for decades, but are inconsistent with biological features of the brain, such as causality and locality. We derive an approximation to gradient-based learning that comports with these constraints by requiring synaptic weight updates to depend only on local information about pre- and postsynaptic activities, in addition to a random feedback projection of the RNN output error. In addition to providing mathematical arguments for the effectiveness of the new learning rule, we show through simulations that it can be used to train an RNN to perform a variety of tasks. Finally, to overcome the difficulty of training over very large numbers of timesteps, we propose an augmented circuit architecture that allows the RNN to concatenate short-duration patterns into longer sequences.
Hybrid quantum systems based on magnonics
Authors: Lachance-Quirion Dany , Tabuchi Yutaka , Gloppe Arnaud , Usami Koji , Nakamura Yasunobu
Published: May 2019

Engineered quantum systems enabling novel capabilities for computation and sensing have blossomed in the last decade. Architectures benefiting from combining complementary physical systems have emerged as promising approaches for quantum technologies. A new class of hybrid quantum systems based on collective spin excitations in ferromagnetic materials has led to the diverse set of platforms outlined in this review article. The coherent interaction between microwave cavity modes and spin-wave modes is presented as a key ingredient for the development of more complex hybrid systems. Indeed, quanta of excitation of the spin-wave modes, called magnons, can also interact coherently with optical photons, phonons, and superconducting qubits in the fields of cavity optomagnonics, cavity magnomechanics, and quantum magnonics, respectively. Notably, quantum optics experiments in magnetically-ordered solid-state systems are within reach thanks to quantum magnonics. Applications of hybrid quantum systems based on magnonics for quantum information processing and quantum sensing are briefly outlined.
Double decoupling effectiveness of water consumption and wastewater discharge in China’s textile industry based on water footprint theory
Authors: Li Yi , Wang Yi
Published: May 2019

As a traditional pillar industry in China, the textile industry has been intensifying the pressure of the water resource load and its reduction of water environment emissions over the years. Decoupling water resource consumption and wastewater discharge require decoupling from economic growth to realise the sustainable development of the textile industry. On the basis of water footprint and decoupling theories, this paper analysed the water consumption decoupling, wastewater discharge decoupling, as well as the double decoupling of water consumption and wastewater discharge of China’s textile industry and its three sub-industries (Manufacture of Textile, Manufacture of Textile Wearing and Apparel, Manufacture of Chemistry) from 2001 to 2015. In those years, the sum of the decoupling index in the double-decoupling years is 249, lower than that in high-decoupling years of water consumption (250) and wastewater discharge (325). Compared with the decoupling of water consumption and of wastewater discharge, the double decoupling is lower, which proves that the conditions for realizing double decoupling are stricter. The double decoupling analysis of water consumption and wastewater discharge, namely, the overall consideration of water resource consumption and water environment pollution, could be used to more effectively promote the realisation of water decoupling in the textile industry.
The Happy Worker
Authors: Hosie Peter , ElRakhawy Nada
Published: May 2019

Conventional wisdom and management theory both support the “happy–productive worker” thesis. Extensive investigation has found qualified support for the impact of employee job happiness on their performance. In this chapter, practical suggestions are made on how to introduce workplace initiatives capable of improving the quality of employees' life and job performance.
Stress, Health, and Wellbeing in Practice
Authors: Quick James Campbell , Bennett Joel , Blake Hargrove M.
Published: May 2019

Conventional wisdom in the field of management emphasizes the reduction of stress in the workplace. Although the authors of this chapter recognize the demonstrated destructive nature of negative stress, they argue that the introduction of positive stress has the potential to improve the health and wellbeing for organizations and workers. Five positive pathways through which stress can contribute to building a healthy workplace are explored: strength of character, self‐awareness, power sharing, requisite self‐reliance, and a supportive organizational culture. Following a summary and integration of these five positive pathways, the authors offer essential practical suggestions related to stress interventions which promote healthy organizations and people. Finally, the chapter presents some promising findings from a review of the stress intervention literature.
MindMatters
Authors: Rowling Louise , Hazell Trevor
Published: May 2019

MindMattersis an innovative Australian mental health promotion and prevention initiative disseminated nationally from 2000, to all schools with a secondary enrolment. It is a comprehensive approach that addresses multiple wellbeing outcomes in the context of a coordinated whole‐school community approach. Key positive outcomes include demonstration of paradigmatic shifts, as a result of the public health and mental health nexus, and a significant increase in the ability of schools to undertake mental health and wellbeing actions. Student outcomes include improved attachment to school, autonomy experience, school attachment, and effective help seeking. No longer is mental health and wellbeing seen as a specialized area of expertise, rather in a decade many Australian school communities have recognized the integral synergistic relationship of mental health and wellbeing, and school achievement. This has resulted in school personnel having the confidence and skills to promote the wellbeing of all school community members and change structures and processes as well as individual behaviors to maximize positive outcomes. This has involved: reconceptualizing mental health as a positive concept, separate but linked to mental illness; the promotion of mental health and wellbeing as an integral element for current school organizational change; building leadership throughout the school community especially by strengthening the capacity of student leaders; reshaping of school partnerships with the mental health sector from being the recipient of programs developed by outsiders to approaches based on school community involvement and ownership; and capitalizing on and enhancing the existing systemic collaboration between health and education sectors nationally.
Wellbeing and Green Spaces in Cities
Authors: Sullivan William
Published: May 2019

There is mounting evidence that exposure to green spaces enhances a person's capacity to manage the demands and pressures of modern living. But how could this be? Through what process or pathways could neighborhood green spaces have such impacts? What evidence supports such claims? This chapter addresses these questions by examining three pathways—and the empirical evidence in support of each—through which exposure to urban green spaces might promote wellbeing. The chapter ends with a call to action that will ensure that people around the world have access to nature at every doorstep.
Introduction
Authors: Cooper Cary L. , Kirkwood Thomas B. L.
Published: May 2019

Far too often, the “aging population” is seen only as a “problem,” characterized by poor health, diminished quality of life, and burdensome economic demands. In reality the extra years that have been gained are mostly good ones, with relatively little change, for better or worse, in the length of the average period of frailty that occurs at the end of a long life. The difference is that a larger fraction of the population now survives into advanced old age. Therefore, the issues around wellbeing in later life, which have always been with us, have assumed a greatly increased numerical significance and become a central concern for societies around the world. This chapter sets out the scope and agenda for this book, highlighting the great diversity that exists among older people and offering, on the whole, a more positive approach to the maintenance of wellbeing through life than is often the case.
Maintaining Wellbeing Through the End of Life
Authors: Hughes Julian C.
Published: May 2019

This chapter starts by considering some of the philosophical issues around the notion of wellbeing. Aristotle and his conception of the good life are clearly of importance. In one way or another his views are relevant to standard interpretations of wellbeing in terms of pleasure (hedonism), desire‐satisfaction, an objective list, or perfectionism. The ideas that emerge from the philosophical literature are relevant to the idea of wellbeing in dementia. For instance, Tom Kitwood linked wellbeing to the perfectionism of an objective list. But this work also ties wellbeing to the notion of personhood. Thus we require a broader philosophical background to wellbeing, one that draws out the importance of our interconnectedness and interdependence, and which is relevant to how wellbeing is maintained through the end of life.
Combined application of pharamcokinetic DCE‐MRI and IVIM‐DWI could improve detection efficiency in early diagnosis of ductal carcinoma in situ
Authors: Tao Wei‐jing , Zhang Hui‐xin , Zhang Lian‐mei , Gao Feng , Huang Wei , Liu Yan , Zhu Yan , Bai Gen‐ji
Published: May 2019

Purpose

Ductal carcinoma in situ (DCIS) is a precursor of invasive ductal breast carcinoma (IDC). This study aimed to use pharamcokinetic dynamic contrast‐enhanced magnetic resonance imaging (DCE‐MRI) and intravoxel incoherent motion diffusion‐weighted imaging (IVIM‐DWI) for the early diagnosis of DCIS.

Methods

Forty‐seven patients, including 25 with DCIS (age: 28–70 yr, mean age: 48.7 yr) and 22 with benign disease (age: 25–67 yr, mean age: 43.1 yr) confirmed by pathology, underwent pharamcokinetic DCE‐MRI and IVIM‐DWI in this study. The quantitative parameters Ktrans, Kep, Ve, Vp, and D, f, D* were obtained by processing of DCE‐MRI and IVIM‐DWI images with Omni‐Kinetics and MITK‐Diffusion softwares, respectively. Parameters were analyzed statistically using GraphPad Prism and MedCalc softwares.

Results

All low‐grade DCIS lesions demonstrated mass enhancement with clear boundaries, while most middle‐grade and high‐grade DCIS lesions showed non‐mass‐like enhancement (NMLE). DCIS lesions were significantly different from benign lesions in terms of Ktrans, Kep, and D (t = 5.959, P < 0.0001; t = 5.679, P < 0.0001; and t = 5.629, P < 0.0001, respectively). The AUC of Ktrans, Kep, D and the combined indicator of Ktrans, Kep, and D were 0.936, 0.902, 0.860, and 0.976, respectively. There was a significant difference in diagnostic efficacy only between D and the combined indicator (Z = 2.408, P = 0.016).

Conclusion

DCE‐MRI and IVIM‐DWI could make for the early diagnosis of DCIS, and reduce the misdiagnosis of DCIS and over‐treatment of benign lesions.
Secondary Pyroelectric Effect and Figure of Merit of Ferroelectric 0–3 Composites
Authors: Ando Daisuke , Eichhorn Franziska , Fey Tobias , Kakimoto Ken‐ichi
Published: May 2019

By mixing lead‐free piezoelectric Li0.06(Na0.50K0.50)0.94NbO3 (LNKN) ceramic particles and polysiloxane, the authors synthesize a novel pyroelectric element that exhibits an enhanced secondary pyroelectric effect. The composite with an LNKN filler ratio of 30 vol% exhibits a homogeneous microstructure and a strong contact between the LNKN filler and the polysiloxane matrix. Thus, the secondary pyroelectric effect originating from such an interaction accounts for approximately half of the total pyroelectric coefficient (i.e 29 μC/m2K) and enhanced the figure of merit of the composite (1.1 μC/m2K).
Multiple Superwettable Nanofiber Arrays Prepared by a Facile Dewetting Strategy via Controllably Localizing a Low‐Energy Compound
Authors: Tang Zhongxue , He Meijin , Bian Ruixin , Duan Zhongfeng , Luan Kang , Hou Jiexin , Hu Binbin , Jiang Lei , Liu Huan
Published: May 2019

Superwettable solid surfaces have attracted substantial research interest due to their outstanding performance. Various approaches have been developed for preparing superwettable surfaces via constructing a highly textured surface roughness and/or altering the surface free energy. Here, a facile dewetting strategy is proposed to produce multiple superwettabilities on copper hydroxide nanofiber arrays (Cu(OH)2‐NFAs) by controlling the localized state of low‐energy silicone oil. It is proposed that both the capillary forces along each nanofiber and the evaporation of the octane solvent contribute to the localization of the silicone oil in the NFAs. By varying the concentration of the silicone oil, its localized state changes from a scattered discontinuous distribution to a continuous thin/thick film, which leads to variations in the surface energy and surface roughness. Consequently, Cu(OH)2‐NFAs with superhydrophilicity, superhydrophobicity with both high and low adhesion, and super slippery properties are prepared. Notably, a very small amount of silicone oil can alter the surface wettability of the Cu(OH)2‐NFAs from superhydrophilic to superhydrophobic, which is attributable to the migration of silicone oil to the top of the nanofibers during the dewetting process. These results will provide new insights on the facile fabrication of functional surfaces with multiple superwettabilities.
A Universal Converse Voltage Process for Triggering Transition Metal Hybrids In Situ Phase Restruction toward Ultrahigh‐Rate Supercapacitors
Authors: Guo Wei , Yu Chang , Li Shaofeng , Song Xuedan , Huang Huawei , Han Xiaotong , Wang Zhao , Liu Zhibin , Yu Jinhe , Tan Xinyi , Qiu Jieshan
Published: May 2019

Defect engineering holds great promise for precise configuration of electrode materials for dramatically enhanced performance in the field of energy storage, but the high energy/large time cost and lack of control involved in this process represent a serious limit to its use. In response, a low‐energy‐cost and ultrafast universal converse voltage process is developed to effectively activate the capacitive performance of transition metal compounds integrated on carbon fiber paper, including Co‐, Ni‐, Mn‐, Fe‐, and Cr‐based hybrids. As a representative example, this process triggers a phase conversion from cobalt hydroxide to electric‐field‐activated CoOOH (EA‐CoOOH), leading to the formation of molecular structure with abundant defects, lattice disorders, and connecting holes, responsible for an enhanced performance within 10 min at room temperature. Moreover, the retained Co2+ in EA‐CoOOH results in increased activity, confirmed by density functional theory calculations. Consequently, these EA‐CoOOH hybrids deliver a capacitance value of 832 F g−1 at a current density of 1 A g−1 and exhibit a retention rate up to 78% (649 F g−1) at a super‐large current density of 200 A g−1. This technology paves a way for ultrafast configuration/modulation of defects on advanced materials toward application in the fields of energy and catalysis.
Rhodium‐Catalyzed ortho‐Arylation of (Hetero)aromatic Acids
Authors: Weber Philip , Rank Christian K. , Yalcinkaya Enis , Dyga Marco , van Lingen Tim , Schmid Rochus , Patureau Frederic W. , Gooßen Lukas J.
Published: May 2019

Rhodium acetate effectively promotes the carboxylate‐directed ortho‐arylation of (hetero)aromatic carboxylates with aryl bromides. The main advantage of this phosphine‐free, redox‐neutral method arises from its efficiency in assembling biologically meaningful electron‐rich arylpyridines, which are problematic substrates in known C−H arylations using Pd, Ru, and Ir catalysts.

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Directed Assembly of Nanoparticle Threshold‐Selector Arrays
Authors: Speckbacher Maximilian , Rinderle Michael , Kaiser Waldemar , Osman Eiman A. , Chryssikos Domenikos , Cattani‐Scholz Anna , Gibbs Julianne M. , Gagliardi Alessio , Tornow Marc
Published: May 2019

The directed assembly of ordered arrays of cubic silver nanoparticles featuring distinct electrical threshold‐switching characteristics is reported. Threshold selectors are key elements for nonvolatile resistive random‐access‐memory architectures, as they suppress sneak path currents in crosspoint arrays. Nanocubes are site‐selectively immobilized on a TiO2‐coated silicon surface via a complementary molecular surface functionalization of nanoparticles and substrate based on a Cu(I)‐catalyzed alkyne‐azide cycloaddition without any physical template. Electrical characterization of individual silver nanocubes by conductive‐probe atomic force microscopy reveals pronounced and reproducible threshold‐switching behavior, featuring ultralow OFF currents below 1 pA, steep turn‐on slopes of <50 mV dec−1 and ON‐OFF ratios in excess of 103. Numerical simulation of Ag‐ion migration dynamics in the TiO2 electrolyte using a kinetic Monte Carlo model supports a switching mechanism based on conductive filament formation from Ag nanoclusters, and their reversible rupture in the low‐voltage regime. Assembled Ag nanocube threshold selectors are proposed for applications in memristive memory architectures, in particular for future highly integrated 3D circuitry.
Pilot‐scale experimental studies on ethanol purification by cyclic stripping
Authors: Maleta Vladimir N. , Bedryk Olesja , Shevchenko Alexander , Kiss Anton A.
Published: May 2019

Cyclic distillation is a proven process intensification method for enhanced separation of various mixtures. It uses an alternative operating mode based on separate phase movement which leads to important practical advantages (vs conventional mode) such as increased column throughput, lower equipment cost (using much less trays at the same reflux ratio) and reduced energy requirements by 20–35% (smaller reflux ratio at the same number of stages), and better separation performance (up to three times). However, if the impurities to be separated are in very low amounts in the feed then distillation is not favorable from an energy use viewpoint. This article is the first to report the practical performance of a continuous process for ethanol purification by air stripping using a cyclic mode of operation, a novel process that avoids the costs of distillation. The purification of ethanol food grade (96.4 vol%) from volatile impurities (0.5 vol%) such as esters, aldehydes, and alcohols, is carried out in a hydro‐selective column with five stages. The lightweight impurities are removed from a stream that is the head fraction of a distillation column. This is usually a waste stream amounting to 3–6% of the plant production rate. By concentrating the stream with impurities, more ethanol is produced such that the losses are reduced to only 1–1.5% of the plant capacity. Based on the experimental results presented in this work, a process consisting of two air stripping columns using cyclic operation is proposed for industrial implementation.
Differences in flowering time maintain species boundaries in a continental radiation ofViburnum
Authors: Spriggs Elizabeth L. , Schlutius Caroline , Eaton Deren A. , Park Brian , Sweeney Patrick W. , Edwards Erika J. , Donoghue Michael J.
Published: May 2019

Premise

We take an integrative approach in assessing how introgression and Pleistocene climate fluctuations have shaped the diversification of the coreLentagoclade ofViburnum, a group of five interfertile species with broad areas of sympatry. We specifically tested whether flowering time plays a role in maintaining species isolation.

Methods

RAD‐seq data for 103 individuals were used to infer the species relationships and the genetic structure within each species. Flowering times were compared among species on the basis of historical flowering dates documented by herbarium specimens.

Results

Within each species, we found a strong relationship between flowering date and latitude, such that southern populations flower earlier than northern ones. In areas of sympatry, the species flower in sequence rather than simultaneously, with flowering dates offset by ≥9 d for all species pairs. In two cases it appears that the offset in flowering times is an incidental consequence of adaptation to differing climates, but in the recently diverged sister speciesV. prunifoliumandV. rufidulum, we find evidence that reinforcement led to reproductive character displacement. Long‐term trends suggest that the two northern‐most species are flowering earlier in response to recent climate change.

Conclusions

We argue that speciation in theLentagoclade has primarily occurred through ecological divergence of allopatric populations, but differences in flowering time were essential to maintain separation of incipient species when they came into secondary contact. This combination of factors may underlie diversification in many other plant clades.
N‐Heterocyclic Carbene Catalyzed Radical Coupling of Aldehydes with Redox‐Active Esters
Authors: Song Runjiang , Chi Yonggui Robin
Published: May 2019

N‐Heterocyclic carbene catalyzed radical reactions are challenging and underdeveloped. In a recent study, Ohmiya, Nagao and co‐workers found that aldehyde carbonyl carbon centers can be coupled with alkyl radicals under NHC catalysis. An elegant aspect of this study is the use of a redox‐active carboxylic ester that behaves as an single‐electron oxidant to convert the Breslow intermediate into a radical adduct and concurrently release an alkyl radical intermediate as a reaction partner.
Design and preparation of ZnS‐ZnFe2O4: a green and efficient hybrid nanocatalyst for the multicomponent synthesis of 2,4,5‐triaryl‐1H‐imidazoles
Authors: Varzi Zahra , Maleki Ali
Published: May 2019

In the present work, a new protocol was introduced for the preparation of an efficient hybrid nanocatalyst ZnS‐ZnFe2O4 via the co‐precipitation method as well as its application in the synthesis of 2,4,5‐triaryl‐1H‐imidazoles derivatives starting from various aromatic aldehydes, benzil and ammonium acetate under ultrasonic irradiation in ethanol. ZnS‐ZnFe2O4 was characterized by Fourier transform infrared (FT‐IR) spectroscopy, energy‐dispersive X‐ray spectroscopy (EDS) analysis, scanning electron microscopy (SEM) image, X‐ray diffraction (XRD) pattern and vibrating sample magnetometer (VSM) curve. This method has advantages such as high efficiency of the heterogeneous catalyst, the use of environmentally‐friendly solvent, high yields, short reaction times and easy isolation of the products and chromatography‐free purification. Our outcomes illustrated that the present nanocatalyst with nearly spherical and Cauliflower‐like morphology and average particle size of 36 nm could be applied as an effective and magnetically recyclable catalyst without any significant decreasing of activity. Furthermore, the synergic effect of bimetallic Lewis acids was studied for the synthesis of imidazole derivatives.
Medium dielectric constant and low‐loss PTFE composites filled with MgO‐LiF co‐doped Li2TiO3 particles
Authors: Wang Hao , Yang Hui , Tong Jianxi , Zhang Qilong
Published: May 2019

In this work, we presented a simple strategy to fabricate medium dielectric constant and low‐loss composites for microwave substrate applications. MgO‐LiF co‐doped Li2TiO3 (LT) powders were fabricated by the solid‐state reaction route and modified by perfluorooctyltriethoxysilane (F8261). The LT/polytetrafluoroethylene (PTFE) composites were fabricated by cold pressing and hot treatment. The XPS and contact angle analysis indicated that the fluorinated group was introduced to LT particle successfully. The effects of modified LT powders content on the dielectric, thermal, and mechanical properties of composites were investigated. As the modified LT content increases, the dielectric constant, dielectric loss, and temperature coefficient of dielectric constant (τε) increase while the bending strength and coefficient of thermal expansion (CTE) decrease, which is attributed to the higher dielectric constant of LT ceramic, more pores, stable τε of LT ceramic, interface defects and low CTE of LT ceramic, respectively. The composites with 60 wt % LT exhibit the best microwave dielectric properties: εr = 6.8, tanδ = 0.001, τε = −29.6 ppm °C−1 at 8 GHz and acceptable coefficient of thermal expansion (28.3 ppm °C−1). Therefore, modified LT powders filled PTFE composites are potential materials for high‐frequency microwave substrate applications. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019, 136, 47980.
Infusible acrylic thermoplastic resins: Tailoring of chemorheological properties
Authors: Cousins Dylan S. , Howell Jackson , Suzuki Yasuhito , Samaniuk Joseph R. , Stebner Aaron P. , Dorgan John R.
Published: May 2019

Infusible liquid resins that polymerize into a thermoplastic are desirable for many applications. Similar to unsaturated and vinylester thermosetting systems, they consist of polymers dissolved in reactive monomer. This work presents a method to decrease cycle time by tuning the molecular weight and concentration of the predissolved polymer in the resin. Variation of these properties allows precise control of the viscosity which in turn controls the time at which peak exotherm is reached, the maximum temperature for a given part thickness, and cure time. Predictive models for the viscosity dependence on molecular weight, polymer concentration, shear rate, and temperature are developed. Two fiberglass panels are fabricated and tested; one with a lower molecular weight (Mw~30 kg mol−1) poly(methyl methacrylate) dissolved in methyl methacrylate and the second with higher molecular weight (Mw~500 kg mol−1) predissolved polymer in the resin. Mechanical properties are indistinguishable but the lower molecular weight panel cures up to three times faster. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019, 136, 48006.
A shell disc bead maker's workshop from Kavewa Island, northern Fiji
Authors: BURLEY DAVID V. , FREELAND TRAVIS
Published: May 2019

Test excavations of an early Lapita colonising site on Kavewa Island off the north‐east coast of Vanua Levu in 2012 encountered an abundant assemblage of Anadara shell disc beads and preforms, as well as lithic micro‐drills for bead perforation. Concentrated in the upper strata of a 1 × 1 m unit, radiocarbon dates place this assemblage in the interval 2490–2280 calBP. Production stages (chaîne opératoire) in bead manufacture are described as is the fabrication of micro‐drills through bipolar flaking of small quartz, chalcedony and chert clasts, locally acquired from Malau breccia. A survey of the Oceanic literature relating to stone drills and shell bead production finds a comparable assemblage only at Bootless Bay, Motupore Island, Papua New Guinea. This assemblage, however, is 3500 km distant and 1750 years more recent in time. The production of beads and micro‐drills represents specialised expertise. Whether this supported an external exchange system, or was exclusively related to household use, cannot be determined.
Synthesis of 2‐(2‐oxo‐2H‐chromen‐4‐yl)acetamides as potent acetylcholinesterase inhibitors and molecular insights into binding interactions
Authors: Kara Jiraporn , Suwanhom Paptawan , Wattanapiromsakul Chatchai , Nualnoi Teerapat , Puripattanavong Jindaporn , Khongkow Pasarat , Lee Vannajan Sanghiran , Gaurav Anand , Lomlim Luelak
Published: May 2019

Sixteen novel coumarin‐based compounds are reported as potent acetylcholinesterase (AChE) inhibitors. The most active compound in this series, 5a (IC50 0.04 ± 0.01 µM), noncompetitively inhibited AChE with a higher potency than tacrine and galantamine. Compounds 5d, 5j, and 5 m showed a moderate antilipid peroxidation activity. The compounds showed cytotoxicity in the same range as the standard drugs in HEK‐293 cells. Molecular docking demonstrated that 5a acted as a dual binding site inhibitor. The coumarin moiety occupied the peripheral anionic site and showed π‐π interaction with Trp278. The tertiary amino group displayed significant cation‐π interaction with Phe329. The aromatic group showed π‐π interaction with Trp83 at the catalytic anionic site. The long chain of methylene lay along the gorge interacting with Phe330 via hydrophobic interaction. Molecular docking was applied to postulate the selectivity toward AChE of 5a in comparison with donepezil and tacrine. Structural insights into the selectivity of the coumarin derivatives toward huAChE were explored by molecular docking and 3D QSAR and molecular dynamics simulation for 20 ns. ADMET analysis suggested that the 2‐(2‐oxo‐2H‐chromen‐4‐yl)acetamides showed a good pharmacokinetic profile and no hepatotoxicity. These coumarin derivatives showed high potential for further development as anti‐Alzheimer agents.
Müssen Imperfektionen bei der Bemessung von brandbeanspruchten Stahlbetonstützen berücksichtigt werden?
Authors: Richter Ekkehard , Zehfuß Jochen
Published: May 2019

Im vorliegenden Beitrag wird der Einfluss von Imperfektionen auf die Zuverlässigkeit von brandbeanspruchten Stahlbeton‐Kragstützen – schwerpunktmäßig der Feuerwiderstandsklasse R 90 – untersucht. Dabei wird „Zuverlässigkeit“ im Sinne von DIN EN 1990 als die Fähigkeit eines Bauteils verstanden, die festgelegten Anforderungen innerhalb der geplanten Nutzungsdauer zu erfüllen. Die Zuverlässigkeit wird in der Regel mit probabilistischen Größen ausgedrückt.

Auslöser der Untersuchungen war ein Beitrag von Pauli in [1], in dem darauf hingewiesen wurde, dass der Nachweis mit dem allgemeinen Rechenverfahren nach DIN EN 1992‐1‐2 oftmals eine geringere Feuerwiderstandsdauer ergibt als die Nachweise mit tabellierten Werten bzw. mit dem vereinfachten Berechnungsverfahren. Als Ursache der Diskrepanzen wurde die fehlende Regelung über Imperfektionen im Zusammenhang mit einer Heißbemessung genannt.