4,871 research outputs found

    Community college students\u27 plant biodiversity learning experience in an introductory biology course: exploring the value added by using a CD-ROM to develop inquiry lessons

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    This study examined the value added to standard textbook-based instruction of plant biodiversity by the use of the exemplary interactive CD-ROM, Conserving Earth’s Biodiversity. This CD-ROM features renowned conservation figure E.O. Wilson. The setting of the research was an introductory biology course in a rural public community college in the Deep South. Six participants were purposively selected to represent three levels of achievement and two groups, the CD-ROM group (exposed to CD-ROM in addition to the textbook) and the textbook group (only course textbook). Students experienced lecture-based, textual, virtual, and real experiences, and examined their ability to understand biodiversity-related concepts and to pursue guided-inquiry questions about local plant biodiversity. Their performance was assessed through activities, quizzes, concept maps, interviews, surveys, and students’ presentations. This study led to three main findings. First, use of the CD-ROM, in addition to the textbook, allowed students to form a well-rounded grasp of plant biodiversity. Second, use of the CD-ROM enhanced the development of inquiries on local plant biodiversity and the metacognitive phase of assigning roles for local plant diversity. Third, the Plant Biodiversity Literacy Rubric [PBLR] was developed, based upon the history of the concept of biodiversity and was used to evaluate students’ progress by assigning them to various levels of understanding during the study. The students in the CD-ROM group gained a broader perspective of plant biodiversity-related concepts, such as levels of biodiversity, hot spots, genetic diversity, food plant diversity, and threats to biodiversity. The CD-ROM was never detrimental to the learning process. They were more self-directed in their development of inquiries, felt more confident about their presentations, and were more metacognitive during their inquiries. Performance on specific activities such as the essay and The Golden List of Species suggested an enhanced cognitive-behavioral/affective experience for students in the CD-ROM group. The PBLR is an exportable instrument, which may allow ecology educators at all levels to assess student’s levels of understanding in a sensitive way. At this time, it is critical to gauge effective understanding of plant biodiversity and ecology education, as it is vital to the survival and well-being of life on Earth

    Extended mean-variance model for reliable evolutionary portfolio optimization

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    Real world optimization of financial portfolios pose a challenging multiobjective problem that can be tackled using Evolutionary Algorithms. The fact that the optimization process is subject to the presence of uncertainty concerning asset returns is likely to lead to unreliable solutions. This work suggests extending the classic mean-variance optimization problem with a third explicit robustness objective. This results on sets of portfolios that can be subsequently grouped together according to their reliability. This additional information allows for a better informed decision making regarding asset allocation. © 2014 - IOS Press and the authors. All rights reserved.Financial support granted by the Spanish Ministry of Science under contract TIN2011-28336 (MOVES)

    Moisture AïŹƒnity of HDPE/Phase-Change Material Composites for Thermal Energy Storage Applications

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    Moisture adsorption can degrade the structural integrity of thermal energy storage devices and can negatively impact the capacity and charging/discharging behavior. Steady-state and transient experiments are conducted at various operating temperatures to evaluate the moisture aïŹƒnity of organic phase-change material (PCM) shape stabilized with high-density polyethylene (HDPE)

    Novel method of severe plastic deformation - Continuous closed die forging: CP aluminum case study

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    There is a large number of methods for severe plastic deformation (SPD). Multidirectional forging (MDF) is probably one of the most easily scalable for industrial application. In general, two main conditions need to be fulfilled for successful SPD processing: constan t sample geometry and application of a quasi - hydrostatic pressure. The first condition is necessary for strain accumulation by repetitive deformation and the second one helps preventing cracking in the specimens with high accumulated strain. However, MDF i s not providing quasi - hydrostatic condition in the processed sample. This paper reports a novel method for severe plastic deformation, namely continuous close d die forging (CCDF), which fulfils both requirements for the successful deformation of samples to a very high accumulated strain. Commercially pure aluminum (1050) was processed to a total strain of 24 by CCDF. After processing, the microstructure was refined down to a mean grain size of 0. 78 ”m . Tensile testing showed good mechanical properties: yiel d strength and ultimate tensile strength of the ultrafine - grained (UFG) aluminum were 180 and 226 MPa, respectively. Elongation to rupture was about 18%. The microstructure, microhardness and grain boundary statistics are discussed with regard to the high mechanical properties of the UFG aluminum processed by th is novel method.Peer ReviewedPostprint (author's final draft

    Collaboration of Researchers and Stakeholders: Transforming Educator Preparation

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    This study contributes to the literature on first year teachers by identifying complexities and struggles of becoming a teacher and the implications of district-university partnerships to strengthen our educator preparation program. The importance of partnerships with stakeholders, memorandum of agreements to share data, observations of first year teachers by university faculty, employer surveys, and the first year teacher’s perspectives about how well our university prepared them, as well as how they compare with other first year teachers nationally is addressed. Multiple sources of data were used to provide information about completers, individuals that graduated from the educator preparation program. These include state reports, national trends, and review of survey results next to universities across the United States involved in teacher preparation. Graduates of our teacher preparation program have a 93% retention rate after five years of teaching. The national average is 50% after five years

    Reducing Poverty in California
Permanently

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    If California were to seriously commit to equalizing opportunity and reducing poverty, how might that commitment best be realized? This is of course a hypothetical question, as there is no evidence that California is poised to make such a serious commitment, nor have many other states gone much beyond the usual lip-service proclamations. There are many reasons for California’s complacency, but an important one is that most people think that poverty is intractable and that viable solutions to it simply don’t exist. When Californians know what needs to be done, they tend to go forward and get it done. When, for example, the state’s roads are in disrepair, there are rarely paralyzing debates about exactly how to go about fixing them; instead we proceed with the needed repairs as soon as the funds to do so are appropriated. The same type of sure and certain prescription might appear to be unavailable when it comes to reducing poverty. It is hard not to be overwhelmed by the cacophony of voices yielding a thick stream of narrow-gauge interventions, new evaluations, and piecemeal proposals.1 Although the research literature on poverty is indeed large and may seem confusing, recent advances have in fact been so fundamental that it is now possible to develop a science-based response to poverty. In the past, the causes of poverty were not well understood, and major interventions, such as the War on Poverty, had to be built more on hunch than science. It is an altogether different matter now. The causes of poverty are well established, and the effects of many possible policy responses to poverty are likewise well established. The simple purpose of this essay is to assemble these advances into a coherent plan that would, if implemented, reduce poverty in California substantially

    Effect of nacl replacement by other salts on the quality of bísaro pork sausages (Pgi chouriça de vinhais)

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    Concerned about the trend to reduce salt consumption, the meat industry has been increasing the strategies to produce and commercialize products where the reduction or even the replacement of NaCl is an important goal. The aim of this study was to test the effect of partial NaCl replacement by KCl and Sub4Salt¼ on the quality of pork sausages. Three different formulations (NaCl + KCl, NaCl + Sub4Salt¼, and KCl + Sub4Salt¼) were considered and compared to the control (2% NaCl). Physicochemical properties, chemical composition, and microbiological and sensory characteristics were evaluated. The replacement of NaCl did not affect pH, water activity (aw) or its chemical composition after eight or 16 days ripening time, while a significant sodium reduction was achieved. The oxidation index expressed in TBARS was also not affected by the NaCl substitution and varied between 0.01 to 0.04 of malonaldehyde (MDA) per kg of sample. Similarly, the NaCl replacement did not change the microbiological quality of the sausages, and the production of healthier meat sausages had also no significant effect on their sensory characteristics. Therefore, according to the results obtained, it is viable and a good strategy for the meat industry to produce “reduced sodium content” sausages without affecting their traditional quality.The authors are grateful to the Foundation for Science and Technology (FCT, Portugal) for financial support by national funds FCT/MCTES to CIMO (UIDB/00690/2020); to Bísaro-Salsicharia Tradicional industry and to Laboratory of Carcass and Meat Quality of Agriculture School of Polytechnic Institute of Bragança ‘Cantinho do Alfredo’. Thanks are extended to GAIN (Axencia Galega de Innovación) for supporting this work (grant number IN607A2019/01). The authors are members of the Healthy Meat network, funded by CYTED (ref. 119RT0568).info:eu-repo/semantics/publishedVersio
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