650 research outputs found

    Maximal-entropy random walks in complex networks with limited information

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    J.G.-G. was supported by MICINN through the Ramon y Cajal program and by grants FIS2008-01240 and MTM2009-13848

    AN INVESTIGATION OF THE POTENTIAL BENEFITS OF A FACULTY MENTOR PROGRAM AS RELATED TO HIGH SCHOOL STUDENTS’ ATTITUDES, AFFILIATION, AND SELF-EFFICACY

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    Faculty mentor programs and other types of student advisory programs are a popular topic among educational leaders today. What drives their popularity is the need to personalize students’ learning experiences, a particular problem in large high schools and middle schools. Many studies have found that students who have at least one caring adult who knows them well are less likely to engage in at-risk behaviors. These students are often not only more academically successful, but are happier and healthier young adults. While most educators are in agreement about the need for schools that offer students a personalized setting, how to best go about this often is debated. Many secondary schools have attempted to implement a faculty mentor program or similar student advisory program with mixed results. A lack of research on this topic further clouds the issue. The study was designed to assess the potential benefits associated with a faculty mentor program. Four different instruments were used to measure 9th and 10th grade students’ attitudes, affiliation, and self-efficacy in a school which has a Faculty Mentor program and a similar school with no such program. The results of this study provide the educational community with data that will help guide choices regarding how best to personalize our schools and the efficiency of faculty mentor programs in providing enhanced educational programming for all students. The primary instrument employed in this study was the Charles F. Kettering (CFK), Ltd., School Climate Profile. A one-way between-subjects multivariate analysis of covariance (MANCOVA) was used to examine differences between two levels of the independent variable, students participating in a Faculty Mentor Program and students who did not participate in a mentor program. The dependent variables consisted of the 16 subscales on the CFK School Climate instrument. While many of the CFK subscales measure attitude, six in particular demonstrated the value of participation in the Faculty Mentor Program: High Morale, Cohesiveness, Effective Communications, Effective Teaching-Learning Strategies, Ability to Plan for the Future, and Identification and Working with Conflicts. Students in the treatment group scored significantly higher on each of these subscales when compared with the control group of students. Additional follow-up data specific to the Faculty Mentor Program was provided through three other instruments. These were the Faculty Mentor Program Student Survey, Student interviews, and the Mentor Survey. The first two focused on student perceptions of how effective the Faculty Mentor Program was in meeting its objectives while the latter was specific to mentor perceptions of the same. In all three cases, the data collected on the Faculty Mentor Program showed that it was meeting many of its stated objectives. It can be concluded that participation in a Faculty Mentor Program did, in part, positively impact students’ attitudes, affiliation, and self-efficacy

    Genuine phase diffusion of a Bose-Einstein condensate in the microcanonical ensemble: A classical field study

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    Within the classical field model, we find that the phase of a Bose-Einstein condensate undergoes a true diffusive motion in the microcanonical ensemble, the variance of the condensate phase change between time zero and time tt growing linearly in tt. The phase diffusion coefficient obeys a simple scaling law in the double thermodynamic and Bogoliubov limit. We construct an approximate calculation of the diffusion coefficient, in fair agreement with the numerical results over the considered temperature range, and we extend this approximate calculation to the quantum field.Comment: 9 pages, 6 figure

    Non-diffusive phase spreading of a Bose-Einstein condensate at finite temperature

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    We show that the phase of a condensate in a finite temperature gas spreads linearly in time at long times rather than in a diffusive way. This result is supported by classical field simulations, and analytical calculations which are generalized to the quantum case under the assumption of quantum ergodicity in the system. This super-diffusive behavior is intimately related to conservation of energy during the free evolution of the system and to fluctuations of energy in the prepared initial state.Comment: 16 pages, 7 figure

    Evolution of the macroscopically entangled states in optical lattices

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    We consider dynamics of boson condensates in finite optical lattices under a slow external perturbation which brings the system to the unstable equilibrium. It is shown that quantum fluctuations drive the condensate into the maximally entangled state. We argue that the truncated Wigner approximation being a natural generalization of the Gross-Pitaevskii classical equations of motion is adequate to correctly describe the time evolution including both collapse and revival of the condensate.Comment: 14 pages, 10 figures, Discussion of reversibility of entanglement is adde

    Understanding mobility in a social petri dish

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    Despite the recent availability of large data sets on human movements, a full understanding of the rules governing motion within social systems is still missing, due to incomplete information on the socio-economic factors and to often limited spatio-temporal resolutions. Here we study an entire society of individuals, the players of an online-game, with complete information on their movements in a network-shaped universe and on their social and economic interactions. Such a "socio-economic laboratory" allows to unveil the intricate interplay of spatial constraints, social and economic factors, and patterns of mobility. We find that the motion of individuals is not only constrained by physical distances, but also strongly shaped by the presence of socio-economic areas. These regions can be recovered perfectly by community detection methods solely based on the measured human dynamics. Moreover, we uncover that long-term memory in the time-order of visited locations is the essential ingredient for modeling the trajectories

    Flow graphs: interweaving dynamics and structure

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    The behavior of complex systems is determined not only by the topological organization of their interconnections but also by the dynamical processes taking place among their constituents. A faithful modeling of the dynamics is essential because different dynamical processes may be affected very differently by network topology. A full characterization of such systems thus requires a formalization that encompasses both aspects simultaneously, rather than relying only on the topological adjacency matrix. To achieve this, we introduce the concept of flow graphs, namely weighted networks where dynamical flows are embedded into the link weights. Flow graphs provide an integrated representation of the structure and dynamics of the system, which can then be analyzed with standard tools from network theory. Conversely, a structural network feature of our choice can also be used as the basis for the construction of a flow graph that will then encompass a dynamics biased by such a feature. We illustrate the ideas by focusing on the mathematical properties of generic linear processes on complex networks that can be represented as biased random walks and also explore their dual consensus dynamics.Comment: 4 pages, 1 figur

    Nonprofit Church Leaders’ Perceptions and Lived Experiences Involving Innovation Competency and Change Management: A Phenomenological Study

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    Innovation competency among religious leaders has been an area of study as nonprofit researchers continue to discover that conventional ways of managing change are no longer effective when tackling present issues. Discussions regarding using innovation competency to manage change among religious leaders are vague, despite benefits to the nonprofit sector. The purpose of this qualitative phenomenological study was to explore the lived experiences of nonprofit church leaders to better understand how innovation competency has shaped organizational change results. Boyatzis’ effective job performance model was the conceptual framework that guided this study. Interview data were gathered from 14 participants who met the inclusion criteria of being a leader with innovation competency experience living in New York, New York. Data from the transcripts were inductively analyzed by using computer software and coded techniques for 10 emergent themes. Results revealed improved organizational performance for church leaders who used innovation competency in managing change, along with spirituality and faith. However, emerging themes showed diverse reasons for innovation competency use and its influences on leaders’ behavioral characteristics. Positive social change can be achieved by promoting innovation competency among religious leaders irrespective of spirituality, belief, and doctrine position regarding change management and organizational performance. Outcomes of this study may also provide useful information for religious leaders regarding implementing new ways and programs to help organizational growth

    Videogame Addiction Scale for Children: Psychometric Properties and Gamer Profiles in the Italian Context

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    Given the few studies examining the evaluation of screening tools for videogame addiction among children aged 12 years and under, the present study analyzed (i) the psychometric properties (factorial structure, reliability indices and criterion validity) of the Italian version of the Videogame Addiction Scale for Children (VASC) and (ii) its construct validity using a person-centered approach. Two studies were carried out. In study 1, 728 participants completed a survey including demographic information, questions concerning the amount of time spent in playing videogames, and the Italian version of the VASC. In study 2, 1008 participants completed a survey comprising demographic information, the Italian version of the VASC, the Big Five Questionnaire for Children, and the social dimension subscale of the Multidimensional Self-Concept Scale. Findings supported (i) the four-dimensional first-order factor structure, (ii) full scalar invariance across age groups and partial scalar equivalence across gender, and (iii) reliability and criterion validity of the VASC. The construct validity of the VASC was confirmed by the identification of two distinct profiles (high videogame players vs. low videogame players) and their specific patterns of associations with personality traits and social self-concept. Interaction effects of gender × profiles on personality traits were evidenced. Overall, the findings provided validity for the use of the Italian version of the VASC and extending the body of literature on videogame addiction
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