Student Engagement and Action in Classroom and Community: Place-Based Education and Social Action for the High-Achieving Student

This paper briefly discusses the work done in a college-preparatory, Senior English class to combat the disengagement present in many educational institutions. This disconnect does not allow for learning retention and, therefore, does not allow for students to apply the moment of learning to life outside of the secondary classroom. The work I do is based off of Jessica Singer Early, Bruce Bigelow, Linda Christensen, and many other master teachers who work with the educational designs of Place Consciousness and Social Action within their respective classrooms. The theories of John Dewey and Paulo Freire suggest that a non-traditional style of education – one that is participatory and more democratic in nature – can allow greater student ownership, engagement, and critical thinking. These theories also direct my curricular choices. I work to combine those theories and practices with the high standards set by the state in which I live, the dual credit program connected to the class, and the expectations of the administration in my school. A genuine experience within a community can engage a student in the learning of writing and reading skills, which will in turn allow for true learning retention to occur. Advisor: Robert Brook

Student Engagement and Action in Classroom and Community: Place-Based Education and Social Action for the High-Achieving Student

This paper briefly discusses the work done in a college-preparatory, Senior English class to combat the disengagement present in many educational institutions. This disconnect does not allow for learning retention and, therefore, does not allow for students to apply the moment of learning to life outside of the secondary classroom. The work I do is based off of Jessica Singer Early, Bruce Bigelow, Linda Christensen, and many other master teachers who work with the educational designs of Place Consciousness and Social Action within their respective classrooms. The theories of John Dewey and Paulo Freire suggest that a non-traditional style of education – one that is participatory and more democratic in nature – can allow greater student ownership, engagement, and critical thinking. These theories also direct my curricular choices. I work to combine those theories and practices with the high standards set by the state in which I live, the dual credit program connected to the class, and the expectations of the administration in my school. A genuine experience within a community can engage a student in the learning of writing and reading skills, which will in turn allow for true learning retention to occur. Advisor: Robert Brook

Highly Accurate Determination of Heterogeneously Stacked Van-der-Waals Materials by Optical Microspectroscopy

The composition of Van-der-Waals heterostructures is conclusively determined using a hybrid evaluation scheme of data acquired by optical microspectroscopy. This scheme deploys a parameter set comprising both change in reflectance and wavelength shift of distinct extreme values in reflectance spectra. Furthermore, the method is supported by an accurate analytical model describing reflectance of multilayer systems acquired by optical microspectroscopy. This approach allows uniquely for discrimination of 2D materials like graphene and hBN and, thus, quantitative analysis of Van-der-Waals heterostructures containing structurally very similar materials. The physical model features a transfer matrix method which allows for flexible, modular description of complex optical systems and may easily be extended to individual setups. It accounts for numerical apertures of applied objective lenses and a glass fiber which guides the light into the spectrometer by two individual weighting functions. The scheme is proven by highly accurate quantification of the number of layers of graphene and hBN in Van-der-Waals heterostructures. In this exemplary case, the fingerprint of graphene involves distinct deviations of reflectance accompanied by additional wavelength shifts of extreme values. In contrast to graphene the fingerprint of hBN reveals a negligible deviation in absolute reflectance causing this material being only detectable by spectral shifts of extreme values.Comment: 12 pages, 4 figure

Área foliar específica, biomassa e taxa de crescimento relativo de folhas de cultivares comerciais de Panicum maximum sob sombreamento artificial.

É necessário identificar espécies forrageiras adaptadas ao uso em sistemas silvipastoris. Neste trabalho objetivou-se avaliar o comportamento de três cultivares comerciais (cvs. Massai, Mombaça e Tanzânia) de P. maximum sob sombreamento artificial. A cada 35 dias foram feitos cortes do material vegetal e avaliou-se: área foliar específica (AFE, em cm2/g), biomassa seca (g) e taxa de crescimento relativo (TCR, em g/g/semana) das folhas. Utilizou-se o delineamento de blocos casualizados em esquema fatorial, com quatro repetições, os fatores foram: sombreamento (O, 54 e 81 %) e cortes (1, 2, 3 e 4); com análise individual de cada cultivar. Entre os cortes, não houve diferença na AFE em nenhuma das cvs. O sombreamento de 81% quase duplicou a AFE para todas as cvs., quando comparado com a testemunha. Para Tanzânia não houve interação entre cortes e sombreamento na produção de biomassa seca foliar (BSF). As plantas sob sombreamento de 54% produziram mais BSF que as plantas sob o sombreamento de 81 % ou a pleno sol. Para Massai e Mombaça houve interação entre os fatores, em geral, as plantas sob sombreamento produziram mais BSF do que as não sombreadas. Para todas as cvs., as maiores TCRs foram obtidas na primeira avaliação; nos demais intervalos de corte, todas as TCRs foram negativas. Conclui-se que as cvs avaliadas são adaptadas ao sombreamento, de até 81%; com maior produtividade sób sombreamento de 54 ou 81% do que a pleno sol

Utilization of an Electron-Beam Tester for Determining Internal Electric Field Profiles in Micro-Structured Thin-Film Semiconductor Devices

An electron-beam tester was used to determine the depth profile of the internal potential distribution in an a-Si:H solar cell and hence the internal electric field profile. The a-Si:H solar cells were prepared for the measurements with the electron-beam tester by low-energy chemical plasma beam etching through a plasma-resistant mask structured by electron-beam lithography. In contrast to an earlier work, the solar cells were in situ illuminated and the electric field profiles were determined for new, degraded and in situ annealed solar cells at various cell temperatures. The measuring results demonstrate that the electron-beam testing technique in combination with a suitable micro-structure preparation method is appropriate to measure internal electric field profiles in semiconductor devices as, e.g., solar cells for arbitrarily chosen bias and illumination states

Grass and Forage Plant Improvement in the Tropics and Sub-Tropics

The majority of tropical and subtropical forage grass genera and/or species have not yet been collected, or need further collection to be representative of their natural distribution. New biotechnological techniques will only result in the release of superior forage cultivars if supported by strong breeding programs. More funding and investment in the formation of strong public research teams in forage conservation and improvement are needed to guarantee the sustainability of tropical and subtropical pasture-based livestock systems in the future. The creation of a permanent international working group on tropical and subtropical forages is essential to assist the International Plant Genetic Resources Institute (IPGRI) in prioritising collection, conservation, evaluation and adoption in the tropical/subtropical world for the benefit of mankind

Grass and Forage Plant Improvement in the Tropics and Sub-Tropics

Key points 1. The majority of tropical and subtropical forage grass genera and/or species have not yet been collected, or need further collection to be representative of their natural distribution. 2. New biotechnological techniques will only result in the release of superior forage cultivars if supported by strong breeding programs. 3. More funding and investment in the formation of strong public research teams in forage conservation and improvement are needed to guarantee the sustainability of tropical and subtropical pasture-based livestock systems in the future. 4. The creation of a permanent international working group on tropical and subtropical forages is essential to assist the International Plant Genetic Resources Institute (IPGRI) in prioritising collection, conservation, evaluation and adoption in the tropical/subtropical world for the benefit of mankind