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    Effects of Socio-Cognitive Conflicts on Group Cognition and Group Performance

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    Socio-cognitive conflict is a mechanism that drives cognitive development/learning in collaborative learning. Such conflicts occur when individuals have different perspectives on the same problem. To adequately solve problems, groups face the challenge of integrating different perspectives, which when successful can result in an increase in shared knowledge (i.e., knowledge convergence), an intermediate process-related collaborative learning outcome. Knowledge convergence plays an important role in explaining the quality of group performance, an ultimate collaborative learning outcome. However, students do not always learn from one another in groups, with studies revealing variability in collaborative learning outcomes. Among other factors, their communication can be unproductive or productive. This mixed evidence could be because: (1) interactions have not been analyzed using instruments developed with theoretical and empirical underpinnings within a socio-cognitive conflict paradigm to measure a comprehensive range of socio-cognitive processes; and (2) it is insufficient to assign group tasks without providing any scaffolding. My study acknowledges these issues and uses a randomized experimental design that aims to: (1) Test out a script that strives to scaffold interactions to generate collaborative socio-cognitive processes. To analyze interactions, my study uses an instrument capable of identifying a comprehensive range of socio-cognitive processes; and (2) Examine the effect of socio-cognitive processes on knowledge convergence and consequently on the quality of group performance. Findings suggest that the script offers a promising way to facilitate the type of productive communication to make group-work beneficial. It generated interactions with collaborative socio-cognitive processes. Additionally, the frequency of collaborative socio-cognitive processes is positively related to the increase in shared knowledge in terms of the number of similar elements and statements members had in common after dyads’ interactions. Also, the increase in the number of similar elements is positively related to the quality of dyads’ performance, whereas there is no corresponding effect for statements. Implications for designing collaborative learning activities include requiring the duration of students’ interactions to be long enough to have sufficient collaborative socio-cognitive processes so as to have substantial knowledge convergence and higher quality of group performance. Future studies include addressing issues regarding measurement accuracy in analyzing chat-logs and knowledge convergence

    Setting a research agenda for medical overuse

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    Although overuse in medicine is gaining increased attention, many questions remain unanswered. Dan Morgan and colleagues propose an agenda for coordinated research to improve our understanding of the proble

    On the Origins and Control of Community Types in the Human Microbiome

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    Microbiome-based stratification of healthy individuals into compositional categories, referred to as “enterotypes” or “community types”, holds promise for drastically improving personalized medicine. Despite this potential, the existence of community types and the degree of their distinctness have been highly debated. Here we adopted a dynamic systems approach and found that heterogeneity in the interspecific interactions or the presence of strongly interacting species is sufficient to explain community types, independent of the topology of the underlying ecological network. By controlling the presence or absence of these strongly interacting species we can steer the microbial ecosystem to any desired community type. This open-loop control strategy still holds even when the community types are not distinct but appear as dense regions within a continuous gradient. This finding can be used to develop viable therapeutic strategies for shifting the microbial composition to a healthy configuration

    Optically pumped nanowire lasers: invited review

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    This paper reviews several topics related to optically pumped ZnO nanowire lasers. A systematic study of the various properties of a device as it evolves from the regime of amplified spontaneous emission to laser oscillation above threshold is presented. The key dependence of the laser threshold on nanowire diameter is demonstrated and explained by means of a thorough study of guided modes in semiconducting nanowires for a nanowire-on-substrate geometry. A ‘head on’ detection geometry is used to measure the far-field profile of a nanowire laser and thus identify the modes responsible for lasing. Finally, the temperature behavior of a nanowire laser is reported, and possible mechanisms that may be responsible for gain are suggested.Physic

    Shifting Scales of Urban Transformation: The emergence of the Marmara Urban Region between 1990 and 2015

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    Provincial borders and metropolitan theories are insufficient to explain the scale and dynamics of İstanbul’s contemporary urban development. The mega projects of the Justice and Development Party (JDP) such as the İzmit Bay Bridge, the Northern Projects, the Marmaray Project and the İstanbul-Ankara High Speed Train point to a scalar shift. Triggered by mega projects, these emerging spatio-temporal relations transcend İstanbul’s administrative borders. In the light of these developments, this study will use the term “region” to explain the emerging scale in and around İstanbul; and therefore will propose a new terminology and method to represent this new scale. The study will begin with an introduction to urban theories and concepts that explain contemporary “planetary urbanization” (Lefebvre, 2003; Brenner 2014) beyond fixed-monocentric models and constructed dichotomies such as urban-rural or built environment-nature. This theoretical framework will be followed by a discussion on the method and will then continue with a summary of the urban governance structure in Turkey and the urban planning history of the Marmara Region. Subsequently, the land-use-based analyses which enabled the researcher to demonstrate the transformation of the Marmara Region between 1990 and 2015 from different angles will be discussed. The dissertation will conclude with an overall evaluation of the findings

    The Milky Way Tomography with SDSS. II. Stellar Metallicity

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    Using effective temperature and metallicity derived from SDSS spectra for ~60,000 F- and G-type main-sequence stars (0.2 < g − r < 0.6), we develop polynomial models for estimating these parameters from the SDSS u − g and g − r colors. These photometric estimates have similar error properties as those determined from SDSS spectra. We apply this method to SDSS photometric data for over 2 million F/G stars and measure the unbiased metallicity distribution for a complete volume-limited sample of stars at distances between 500 pc and 8 kpc. The metallicity distribution can be exquisitely modeled using two components with a spatially varying number ratio, which correspond to disk and halo. The two components also possess the kinematics expected for disk and halo stars. The metallicity of the halo component is spatially invariant, while the median disk metallicity smoothly decreases with distance from the Galactic plane from –0.6 at 500 pc to –0.8 beyond several kiloparsecs. The absence of a correlation between metallicity and kinematics for disk stars is in a conflict with the traditional decomposition in terms of thin and thick disks. We detect coherent substructures in the kinematics-metallicity space, such as the Monoceros stream, which rotates faster than the LSR, and has a median metallicity of [Fe/H] = −0.95, with an rms scatter of only ~0.15 dex. We extrapolate our results to the performance expected from the Large Synoptic Survey Telescope (LSST) and estimate that LSST will obtain metallicity measurements accurate to 0.2 dex or better, with proper-motion measurements accurate to ~0.5 mas yr−1, for about 200 million F/G dwarf stars within a distance limit of ~100 kpc (g < 23.5).Astronom

    Morphological complexity reveals verb-specific prefrontal engagement

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    Neuropsychological evidence and recent rTMS studies strongly suggest that damage or inhibition of left prefrontal areas may result in specific impairment of verb morphosyntactic processing. However, functional imaging studies have so far failed to identify an area specifically related to grammatical aspects of verb knowledge. To date very few functional studies have been conducted in languages other than English, a language with limited inflectional morphology. In the present study, we make the hypothesis that neuronal responses for verb grammatical processing may be more or less evident depending on the morphological complexity of verbs in a given language. Exploiting the morphologically rich verbal paradigm typical of the Italian language we implemented an event-related functional MRI design to identify cortical regions that were active when subjects produced nouns or verbs in the context of short phrases. Results showed an area of verb-specific activation for real verbs in a small left frontal region corresponding to the intersection of BA10, BA46 and BA 47. We interpret the results as revealing that languagespecific morphological properties may modulate the pattern of grammatical specific activations. Specifically, higher degrees of morphophonological complexity may engage a greater variety of morphophonological operations, thus enhancing the possibility of activations specific for a given grammatical class.Psycholog

    Optimal All-to-All Personalized Communication with Minimum Span on Boolean Cubes

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    All-to-all personalized communication is a class of permutations in which each processor sends a unique message to every other processor. We present optimal algorithms for concurrent communication on all channels in Boolean cube networks, both for the case with a single permutation, and the case where multiple permutations shall be performed on the same local data set, but on different sets of processors. For K elements per processor our algorithms give the optimal number of elements transfer, K=2. For a succession of all-to-all personalized communications on disjoint subcubes of β dimensions each, our best algorithm yields (K/2)+σ-β element exchanges in sequence, where is the total number of processor dimensions in the permutation. An implementation on the Connection Machine of one of the algorithms offers a maximum speed-up of 50% compared to the previously best known algorithm.Engineering and Applied Science

    Income and Subjective Well-Being: New Insights from Relatively Healthy American Women, Ages 49-79

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    The interests of economists, psychologists, social scientists and others on the relations of income, demographics, religion and subjective well-being, have generated a vast global literature. It is apparent that biomedical research has focused on white with men. The Women’s Health Initiative and Observational Study (WHI OS) was initiated in 1992. The OS represents the scientific need for social priorities to improve the health and welfare of women; it includes 93.676 relatively healthy postmenopausal women, 49 to 79, from diverse backgrounds. The objective of this study is to examine how lifestyle and other factors influence women’s health. Data from the WHI OS questionnaire were analyzed. Statistical methods included descriptive statistics square, correlations, linear regression and analyses of covariance (GLM). New findings and insights relate primarily to general health, religion, club attendance, and likelihood of depression. The most important predictor of excellent or very good health is quality of life and general health is a major predictor of quality of life. A great deal of strength and comfort from religion was reported by 62.98% of the women, with little variation by denomination. More from religion related to poorer health, and less likelihood of depression. Religion and lower income are in accord with of across country studies. Attendance at clubs was associated with religion and with all factors associated with religion, except income. Though general health and likelihood of depression are highly correlated, better health is associated with higher income; however, likelihood of depression is not associated with income—contrary to conventional wisdom about socioeconomic disparities and mental health. Subjective well-being variables, with the exception of quality of life, were not associated with income. Social networks—religion and clubs—among a diverse population, warrant further attention from economists, psychologists, sociologists, and others

    Merging molecular mechanism and evolution: theory and computation at the interface of biophysics and evolutionary population genetics

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    The variation among sequences and structures in nature is both determined by physical laws and by evolutionary history. However, these two factors are traditionally investigated by disciplines with different emphasis and philosophy—molecular biophysics on one hand and evolutionary population genetics in another. Here, we review recent theoretical and computational approaches that address the critical need to integrate these two disciplines. We first articulate the elements of these integrated approaches. Then, we survey their contribution to our mechanistic understanding of molecular evolution, the polymorphisms in coding region, the distribution of fitness effects (DFE) of mutations, the observed folding stability of proteins in nature, and the distribution of protein folds in genomes.Chemistry and Chemical Biolog
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