118 research outputs found

    Field-Induced Slow Magnetic Relaxation In the First Dy(III)-centered 12-Metallacrown-4 Double-Decker

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    The reaction of Dy(O2CMe)3•xH2O and Ga(NO3)3•xH2O led to the isolation of (nBu4N)[GaIII8DyIII(OH)4(shi)8] (1). The compound possesses a unique chemical structure enclosing the central magnetic DyIII ion between diamagnetic GaIII-based metallacrown 12-MC-4 ligands. The double-decker complex exhibits field-induced single-molecule magnet (SMM) behaviour with an effective energy barrier (Ueff) of 39 K (27.1 cm-1). Consistent with the observed slow relaxation of magnetization, theoretical calculations suggest a ground state mainly determined by |±11/2> in the easy axis direction

    Unfolding the procedure of characterizing recorded ultra low frequency, kHZ and MHz electromagetic anomalies prior to the L'Aquila earthquake as pre-seismic ones. Part I

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    Ultra low frequency, kHz and MHz electromagnetic anomalies were recorded prior to the L'Aquila catastrophic earthquake that occurred on April 6, 2009. The main aims of this contribution are: (i) To suggest a procedure for the designation of detected EM anomalies as seismogenic ones. We do not expect to be possible to provide a succinct and solid definition of a pre-seismic EM emission. Instead, we attempt, through a multidisciplinary analysis, to provide elements of a definition. (ii) To link the detected MHz and kHz EM anomalies with equivalent last stages of the L'Aquila earthquake preparation process. (iii) To put forward physically meaningful arguments to support a way of quantifying the time to global failure and the identification of distinguishing features beyond which the evolution towards global failure becomes irreversible. The whole effort is unfolded in two consecutive parts. We clarify we try to specify not only whether or not a single EM anomaly is pre-seismic in itself, but mainly whether a combination of kHz, MHz, and ULF EM anomalies can be characterized as pre-seismic one

    Spontaneous emulsification induced by nanoparticle surfactants

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    Microemulsions, mixtures of oil, water, and surfactant, are thermodynamically stable. Unlike conventional emulsions, microemulsions form spontaneously, have a monodisperse droplet size that can be controlled by adjusting the surfactant concentration, and do not degrade with time. To make microemulsions, a judicious choice of surfactant molecules must be made, which significantly limits their potential use. Nanoparticle surfactants, on the other hand, are a promising alternative because the surface chemistry needed to make them bind to a liquid-liquid interface is both well flexible and understood. Here, we derive a thermodynamic model predicting the conditions in which nanoparticle surfactants drive spontaneous emulsification that agrees quantitatively with experiments using Noria nanoparticles. This new class of microemulsions inherits the mechanical, chemical, and optical properties of the nanoparticles used to form them, leading to novel applications

    Topological insights in polynuclear Ni/Na coordination clusters derived from a schiff base ligand

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    This article presents the syntheses, crystal structures, topological features and magnetic properties of two NiII/NaI coordination clusters (CCs) formulated [NiII3Na(L1)3(HL1 (MeOH)2] (1) and [NiII6Na(L1)5(CO3)(MeO (MeOH)3(H2O)3]·4(MeOH) 2(H2O) [2 4(MeOH) 2(H2O)] where H2L1 is the semi rigid Schiff base ligand (E)-2-(2-hydroxy-3 methoxybenzylideneamino)-phenol). Compound 1 possesses a rare NiII3NaI cubane (3M4-1) topology and compound 2 is the first example in polynuclear Ni/Na chemistry that exhibits a 2,3,4M7-1 topology

    Multidimensional Signals and Analytic Flexibility: Estimating Degrees of Freedom in Human-Speech Analyses

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    Recent empirical studies have highlighted the large degree of analytic flexibility in data analysis that can lead to substantially different conclusions based on the same data set. Thus, researchers have expressed their concerns that these researcher degrees of freedom might facilitate bias and can lead to claims that do not stand the test of time. Even greater flexibility is to be expected in fields in which the primary data lend themselves to a variety of possible operationalizations. The multidimensional, temporally extended nature of speech constitutes an ideal testing ground for assessing the variability in analytic approaches, which derives not only from aspects of statistical modeling but also from decisions regarding the quantification of the measured behavior. In this study, we gave the same speech-production data set to 46 teams of researchers and asked them to answer the same research question, resulting in substantial variability in reported effect sizes and their interpretation. Using Bayesian meta-analytic tools, we further found little to no evidence that the observed variability can be explained by analysts’ prior beliefs, expertise, or the perceived quality of their analyses. In light of this idiosyncratic variability, we recommend that researchers more transparently share details of their analysis, strengthen the link between theoretical construct and quantitative system, and calibrate their (un)certainty in their conclusions

    Mapping the Relationship Among Political Ideology, CSR Mindset, and CSR Strategy: A Contingency Perspective Applied to Chinese Managers

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    The literature on antecedents of corporate social responsibility (CSR) strategies of firms has been predominately content driven. Informed by the managerial sense-making process perspective, we develop a contingency theoretical framework explaining how political ideology of managers affects the choice of CSR strategy for their firms through their CSR mindset. We also explain to what extent the outcome of this process is shaped by the firm’s internal institutional arrangements and external factors impacting on the firm. We develop and test several hypotheses using data collected from 129 Chinese managers. The results show that managers with a stronger socialist ideology are likely to develop a mindset favouring CSR, which induces the adoption of a proactive CSR strategy. The CSR mindset mediates the link between socialist ideology and CSR strategy. The strength of the relationship between the CSR mindset and the choice of CSR strategy is moderated by customer response to CSR, industry competition, the role of government, and CSR-related managerial incentives

    Understanding the rise of faculty-student coaching: an academic capitalism perspective

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    We examine the rise of coaching within management education to support student learning. We question the assumption that faculty-student coaching (FSC) is beneficial and propose that there may be some limitations in the use of FSC that have yet to be adequately acknowledged and discussed in the literature. In particular, we propose that there is currently insufficient evidence to conclude that coaching can produce knowledge acquisition and therefore ask why we persist in the use of FSC when we have limited evidence of its efficacy in delivering a core education outcome. We suggest that the theory of academic capitalism provides a useful, critical lens through which to view the growing trend in FSC, identifying that FSC may be utilized as a method of increasing student satisfaction, perceptions of value for money and as a useful marketing tool for business schools competing for students. However, academic capitalism may also explain the use of coaching via its ability to enhance the skills and attitudes of students, providing outcomes that are valued by students, employers and governments. We conclude our essay by providing recommendations to mitigate these proposed dangers and consequently maximise the effectiveness of coaching as a development tool in management education

    Old wine in new bottles: Exploring pragmatism as a philosophical framework for the discipline of coaching

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    The practice and industry of organizational coaching are now well established, but how it is understood theoretically continues to lag behind. In this paper we analyze possible reasons for this state of affairs and argue that the development of coaching as an academic discipline will benefit from adopting philosophical pragmatism as an overarching theoretical framework. This move will enable coaching academics to utilize the contributions to knowledge that different paradigms generate. Positioning pragmatism as a theory of action we argue that organizational coaching is by default a pragmatic enterprise and provide three examples of the considerable benefits to be gained by conceptualizing it this way. (1) Drawing from the pragmatists’ ideas, particularly those of John Dewey, we demonstrate how the theoretical understanding of organizational coaching can be enhanced by considering its nature as a joint inquiry. (2) Pragmatism suggests development as an ultimate purpose for organizational coaching which also helps to resolve fundamental conceptual debates. (3) In light of the complexity and diversity involved in the way that organizational coaching is practiced, pragmatism offers coaches a useful framework for developing the flexibility required for navigating the multiplicity of influences on their practice

    A local human Vδ1 T cell population is associated with survival in nonsmall-cell lung cancer

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    Murine tissues harbor signature γδ T cell compartments with profound yet differential impacts on carcinogenesis. Conversely, human tissue-resident γδ cells are less well defined. In the present study, we show that human lung tissues harbor a resident Vδ1 γδ T cell population. Moreover, we demonstrate that Vδ1 T cells with resident memory and effector memory phenotypes were enriched in lung tumors compared with nontumor lung tissues. Intratumoral Vδ1 T cells possessed stem-like features and were skewed toward cytolysis and helper T cell type 1 function, akin to intratumoral natural killer and CD8+ T cells considered beneficial to the patient. Indeed, ongoing remission post-surgery was significantly associated with the numbers of CD45RA−CD27− effector memory Vδ1 T cells in tumors and, most strikingly, with the numbers of CD103+ tissue-resident Vδ1 T cells in nonmalignant lung tissues. Our findings offer basic insights into human body surface immunology that collectively support integrating Vδ1 T cell biology into immunotherapeutic strategies for nonsmall cell lung cancer
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