682 research outputs found

    Chapter 5 - The Impact of Preservice Teachers\u27 Experiences and Beliefs on the Learning and Teaching of Peer Conferencing

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    When I finished drafting this chapter, I knew that it would be sent to a reviewer or two who would read it and write feedback that I would be expected to take into account when doing revisions. I would never see these reviewers and we would not have a conversation. I would not have the opportunity to ask them to clarify their comments or to focus on a part of the text that I’d found particularly challenging to write. I would not know if they had frowned over my draft or chuckled out loud or lingered over my language. I would take their feedback and do my best to interpret their meaning, as they had done their best to interpret mine, in isolation from each other. In this situation, the focus is constrained to be solely on the writing product, not on the writing process. As teachers of writing, elementary school teachers focus on the writing products of their students, but they must focus more on the process of writing. They are responsible for teaching their students how to write. As a teacher educator, I am responsible for teaching my students–all preservice teachers–how to teach their students how to write. In order to do that effectively, I must make explicit how writers work. I must help my students engage in the talk that writers use as they make sense of how they work. One of the ways that writers talk about writing is by participating in discussions, focused on their writing products, with other writers. In the lexicon of writing process at the elementary school level, this is commonly referred to as peer conferencing

    Grasshopper and bee communities on Missouri prairies : comparing reconstructions and remnants

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    Tallgrass prairies once occupied a large swath of central North America, but now face the combined challenges of habitat loss and fragmentation. In Missouri, where less than 1% the historical prairie remains, prairies are being reconstructed from agricultural or wooded land. The success of reconstructed grasslands is often assessed based on the extent to which native prairie plants have reestablished. Invertebrates, which make up a large portion of prairie biodiversity, are often assumed to colonize reconstructions if native vegetation returns. However, the limited mobility of many invertebrates, the isolation of many tallgrass remnants, and the difficulty in establishing prairie plants raises serious questions as to whether invertebrate communities on reconstructed prairies are and will be equivalent to those found on remnant prairies. To evaluate the effectiveness of prairie reconstructions in restoring grassland invertebrate communities, we sampled two guilds of terrestrial invertebrates: native bees (Anthophila) and grasshoppers (Acrididae). The first objective of this project was to compare grasshopper and bee communities on reconstructions to those on remnants by evaluating species richness, diversity, and community composition. We sought to identify species or functional groups associated with remnants or reconstructions that could be used to monitor invertebrate communities on reconstructions and remnants in the future. The second objective was to evaluate the effects of prairie reconstruction age on grasshopper and bee communities to determine if communities on reconstructions are converging with remnants.Includes bibliographical reference

    Locating a weak change using diffuse waves (LOCADIFF) : theoretical approach and inversion procedure

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    We describe a time-resolved monitoring technique for heterogeneous media. Our approach is based on the spatial variations of the cross-coherence of coda waveforms acquired at fixed positions but at different dates. To locate and characterize a weak change that occurred between successive acquisitions, we use a maximum likelihood approach combined with a diffusive propagation model. We illustrate this technique, called LOCADIFF, with numerical simulations. In several illustrative examples, we show that the change can be located with a precision of a few wavelengths and its effective scattering cross-section can be retrieved. The precision of the method depending on the number of source receiver pairs, time window in the coda, and errors in the propagation model is investigated. Limits of applications of the technique to real-world experiments are discussed.Comment: 11 pages, 14 figures, 1 tabl

    Algebraic Properties of Valued Constraint Satisfaction Problem

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    The paper presents an algebraic framework for optimization problems expressible as Valued Constraint Satisfaction Problems. Our results generalize the algebraic framework for the decision version (CSPs) provided by Bulatov et al. [SICOMP 2005]. We introduce the notions of weighted algebras and varieties and use the Galois connection due to Cohen et al. [SICOMP 2013] to link VCSP languages to weighted algebras. We show that the difficulty of VCSP depends only on the weighted variety generated by the associated weighted algebra. Paralleling the results for CSPs we exhibit a reduction to cores and rigid cores which allows us to focus on idempotent weighted varieties. Further, we propose an analogue of the Algebraic CSP Dichotomy Conjecture; prove the hardness direction and verify that it agrees with known results for VCSPs on two-element sets [Cohen et al. 2006], finite-valued VCSPs [Thapper and Zivny 2013] and conservative VCSPs [Kolmogorov and Zivny 2013].Comment: arXiv admin note: text overlap with arXiv:1207.6692 by other author

    The STAR MAPS-based PiXeL detector

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    The PiXeL detector (PXL) for the Heavy Flavor Tracker (HFT) of the STAR experiment at RHIC is the first application of the state-of-the-art thin Monolithic Active Pixel Sensors (MAPS) technology in a collider environment. Custom built pixel sensors, their readout electronics and the detector mechanical structure are described in detail. Selected detector design aspects and production steps are presented. The detector operations during the three years of data taking (2014-2016) and the overall performance exceeding the design specifications are discussed in the conclusive sections of this paper

    On the reduction of the CSP dichotomy conjecture to digraphs

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    It is well known that the constraint satisfaction problem over general relational structures can be reduced in polynomial time to digraphs. We present a simple variant of such a reduction and use it to show that the algebraic dichotomy conjecture is equivalent to its restriction to digraphs and that the polynomial reduction can be made in logspace. We also show that our reduction preserves the bounded width property, i.e., solvability by local consistency methods. We discuss further algorithmic properties that are preserved and related open problems.Comment: 34 pages. Article is to appear in CP2013. This version includes two appendices with proofs of claims omitted from the main articl

    QCSP on reflexive tournaments

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    We give a complexity dichotomy for the Quantified Constraint Satisfaction Problem QCSP(H) when H is a reflexive tournament. It is well known that reflexive tournaments can be split into a sequence of strongly connected components H1,…,Hn so that there exists an edge from every vertex of Hi to every vertex of Hj if and only if

    Cooperation between expert knowledge and data mining discovered knowledge: Lessons learned

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    Expert systems are built from knowledge traditionally elicited from the human expert. It is precisely knowledge elicitation from the expert that is the bottleneck in expert system construction. On the other hand, a data mining system, which automatically extracts knowledge, needs expert guidance on the successive decisions to be made in each of the system phases. In this context, expert knowledge and data mining discovered knowledge can cooperate, maximizing their individual capabilities: data mining discovered knowledge can be used as a complementary source of knowledge for the expert system, whereas expert knowledge can be used to guide the data mining process. This article summarizes different examples of systems where there is cooperation between expert knowledge and data mining discovered knowledge and reports our experience of such cooperation gathered from a medical diagnosis project called Intelligent Interpretation of Isokinetics Data, which we developed. From that experience, a series of lessons were learned throughout project development. Some of these lessons are generally applicable and others pertain exclusively to certain project types

    Prevalence of Mental Health Disorder Symptoms and Rates of Help-seeking Among University-Enrolled, Black Men

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    Background. Black men in college represent a subgroup of emerging adults who are at increased risk of developing mental health disorders (MHDs), such as anxiety and depression. Such risk has been attributed to disproportionate experiences with everyday racial discrimination and high levels of psychological distress. Despite being at higher risk, university-enrolled, Black men are not utilizing mental health or health resources at optimal rates. The current evidence base describing prevalence of MHDs and health services utilization among Black men in college is limited. The present study addresses this by examining mental health prevalence among university-enrolled, Black men and their rates of health services utilization. Methods. We analyzed data (N ~ 2500) from a student survey, Spit for Science, a longitudinal, ongoing, research study at a mid-Atlantic, public university. Participants are given surveys in their freshman year and follow-up surveys every spring thereafter. Measures included: mental health disorders (depression and anxiety, as measured by the Symptom Checklist 90) and campus health service utilization (counseling center, health services, wellness center, and recreational sports). We conducted descriptive analyses to determine MHD symptom prevalence and utilization rates; Mann Whitney U tests to compare prevalence rates to White men and Black women; and, Chi-squared tests to compare rates of utilization among groups. Results. During their Freshman year, greater than 60% of students from each ethnic group reported at least one anxiety symptom and greater than 80% reported at least one depressive symptom. By senior year, reporting rates decreased significantly for Black men (49.6%) but remained high for White men (69.1%) and Black women (63%); p \u3c0.000. For depression, results were similar; however, only significant differences between Black men (72.7%) and Black women (87.1%); p\u3c0.000. Black men (20.4%), though reporting high levels of symptoms, still utilized counseling services at lower rates compared to White men (37.76%); p = 0.024. Conclusion. Findings suggest that Black men underutilize available campus health resources despite reporting one or more symptoms associated with anxiety and depression. Further research and prevention efforts are needed to improve help-seeking among this vulnerable population.https://scholarscompass.vcu.edu/gradposters/1077/thumbnail.jp

    The Personal Genome Project-UK, an open access resource of human multi-omics data

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    Integrative analysis of multi-omics data is a powerful approach for gaining functional insights into biological and medical processes. Conducting these multifaceted analyses on human samples is often complicated by the fact that the raw sequencing output is rarely available under open access. The Personal Genome Project UK (PGP-UK) is one of few resources that recruits its participants under open consent and makes the resulting multi-omics data freely and openly available. As part of this resource, we describe the PGP-UK multi-omics reference panel consisting of ten genomic, methylomic and transcriptomic data. Specifically, we outline the data processing, quality control and validation procedures which were implemented to ensure data integrity and exclude sample mix-ups. In addition, we provide a REST API to facilitate the download of the entire PGP-UK dataset. The data are also available from two cloud-based environments, providing platforms for free integrated analysis. In conclusion, the genotype-validated PGP-UK multi-omics human reference panel described here provides a valuable new open access resource for integrated analyses in support of personal and medical genomics
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