2,216 research outputs found
Electron-beam-sustained discharge revisited - light emission from combined electron beam and microwave excited argon at atmospheric pressure
A novel kind of electron beam sustained discharge is presented in which a
12keV electron beam is combined with a 2.45GHz microwave power to excite argon
gas at atmospheric pressure in a continuous mode of operation. Optical emission
spectroscopy is performed over a wide wavelength range from the vacuum
ultraviolet (VUV) to the near infrared (NIR). Several effects which modify the
emission spectra compared to sole electron beam excitation are observed and
interpreted by the changing plasma parameters such as electron density,
electron temperature and gas temperature.Comment: 10 pages, 9 figure
School-Family Partnerships and Teachers, Parents and Children
Early childhood educators are bound by ethical duty and guided by developmentally appropriate practice to foster opportunities for meaningful parent involvement that contributes to building partnerships with families. However, misalignment of state standards and national expectations send mixed messages about how early childhood educators can effectively engage parents and families and cultivate school-family partnerships. This paper synthesized a collection of quantitative, qualitative, mixed method, meta-synthesis, and meta-analysis studies concerning the relationship between parent involvement, children’s learning and development, and school-family partnerships. The studies examined support the idea that parent involvement was a significant contributor to young children’s learning and development no matter how parent involvement was defined and that enhanced partnerships were one of the most influential methods. Research revealed that building partnerships with families required educators to be aware, sensitive, and supportive of many aspects of parents’ and families’ realities. School-family partnerships are also discussed as a foundation for learning communities that recognize teachers, parents, and young children as equitable and active contributors to individual and collective learning
Wirkungen hoher Schwefelgaben auf Mineralstoffgehalte, Proteinfraktionen und Kleberqualität von Weizen aus biologisch-dynamischem Anbau
In der vorgestellten Arbeit sollte geprüft werden, ob hohe Schwefel-Gaben den Dehnwiderstand des Klebers weiter verringern und welche Auswirkungen diese auf die Proteinfraktionen ausüben. Gleichzeitig sollte ein Beitrag zur Schwefel-Ernährung von Weizen unter biologisch-dynamischen Anbauverhältnissen geleistet werden.
Auf einem Winterweizenschlag (Sorte Bussard) eines biologisch-dynamisch wirtÂschaftenden Betriebes (Dottenfelderhof, Bad Vilbel) wurde 1998 zu VegetationsbeÂginn ein SchwefeldĂĽngungsversuch (0, 50, 100, 200, 400 kg S/ha als Kalimagnesia) angelegt.
- Erträge, Stickstoff-, Schwefel-, Kalium- und Magnesium-Gehalte des Korns unterÂschieden sich nicht.
- Dagegen wurden die S-Gehalte des Strohs schon ab einer Gabe von 50 kg S/ha signifikant erhöht.
- Ab Mengen von 200 kg S/ha ergaben sich signifikant niedrigere Gehalte HMW-Glutenin sowie Dehnwiderstände des Klebers.
- Dagegen waren in der RP-HPLC-Analyse des Endospermmehls keine UnterÂschiede erkennbar.
Die Ergebnisse dieses Versuchs sind deshalb so bedeutsam, weil sie die AbhänÂgigkeit der Proteinstruktur des Weizens im Zusammenhang mit der SchwefelversorÂgung in folgender Weise bestätigen:
Während bekannt ist, dass Schwefel-Mangel feste Kleber bzw. Teige induziert, werden die Kleber unter dem Einfluss hoher Schwefel-Gaben (im Ăśberschuss) weiÂcher. Aus solchen Phänomenen konnte dann ein weiterer Aspekt des Leitbildes fĂĽr die ZĂĽchtung von Weizensorten fĂĽr den biologisch-dynamischen Anbau entwickelt werden:
- weichere Kleber
- höhere Gehalte an Albuminen und Globulinen
- gute Proteingehalte (bei akzeptablen Erträgen) durch verbesserte NährstoffaufÂnahme (bessere Durchwurzelung
Perturbation calculations of the interaction energies between non-bonded hydrogen atoms - Part 2
Calculations of the interaction energy between non-bonded hydrogen atoms in the fragments A—H---H'—A' for selected displacements of the hydrogen atoms enable one to evaluate corrections to the force field due to the non-bonded interactions and to discuss the changes in the stretching vibration frequencies of the interacting fragments
Energy-angle dispersion of accelerated heavy ions at 67P/Churyumov–Gerasimenko: implication in the mass-loading mechanism
The Rosetta spacecraft studied the comet 67P/Churyumov–Gerasimenko for nearly two years. The Ion Composition Analyzer instrument on board Rosetta observed the positive ion distributions in the environment of the comet during the mission. A portion of the comet's neutral coma is expected to get ionized, depending on the comet's activity and position relative to the Sun, and the newly created ions are picked up and accelerated by the solar wind electric field, while the solar wind flow is deflected in the opposite direction. This interaction, known as the mass-loading mechanism, was previously studied by comparing the bulk flow direction of both the solar wind protons and the accelerated cometary ions with respect to the direction of the magnetic and the convective solar wind electric field. In this study, we show that energy–angle dispersion is occasionally observed. We report two types of dispersion: one where the observed motion is consistent with ions gyrating in the local magnetic field and another where the energy–angle dispersion is opposite to that expected from gyration in the local magnetic field. Given that the cometary ion gyro-radius in the undisturbed solar wind magnetic and electric field is expected to be too large to be detected in this way, our observations indicate that the local electric field might be significantly smaller than that of the undisturbed solar wind. We also discuss how the energy–angle dispersion, which is not consistent with gyration, may occur due to spatially inhomogeneous densities and electric fields
The Two Faces of Wheat
Wheat-based foods have been staple foods since about 10,000 years and constitute a major source of energy, dietary fiber, and micronutrients for the world population. The role of wheat in our diet, however, has recently been scrutinized by pseudoscientific books and media reports promoting the overall impression that wheat consumption makes people sick, stupid, fat, and addicted. Consequently, numerous consumers in Western countries have started to question their dietary habits related to wheat consumption and voluntarily decided to adopt a wheat-free diet without a medical diagnosis of any wheat-related disorder (WRD), such as celiac disease, wheat allergy, or non-celiac gluten sensitivity. The aim of this review is to achieve an objective judgment of the positive aspects of wheat consumption as well as adverse effects for individuals suffering from WRDs. The first part presents wheat constituents and their positive nutritional value, in particular, the consumption of products from whole-grain flours. The second part is focused on WRDs that affect predisposed individuals and can be treated with a gluten-free or -reduced diet. Based on all available scientific knowledge, wheat consumption is safe and healthy for the vast majority of people. There is no scientific evidence to support that the general population would benefit from a wheat-free diet
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How We Got Here: Connectivity, Creativity, Confluence and Internet Culture
There are more innovations today than at any time in human history. The companies that value creativity and diversity of ideas in their hires are the ones most likely to thrive. Indeed, the key asset of a corporation is the abilities, innovativeness, and creativity of its employees. The authors construct a timeline of critical events leading up to today’s highly networked and interconnected world with its ubiquitous social media technologies. The current state has been influenced by advances in media, technology, military defense, and commerce. One trend that stands out in this timeline is the increasing rate of change. It also becomes apparent that the companies that will survive are the ones that are nimble, sensitive to changes in the competitive environment, and can quickly adapt
Development of a cometosheath at comet 67P/Churuyumov-Gerasimenko: A case study comparison of Rosetta observations
Context: The ionosphere of a comet is known to deflect the solar wind through
mass loading, but the interaction is dependent on cometary activity. We
investigate the details of this process at comet 67P using the Rosetta Ion
Composition Analyzer. Aims: This study aims to compare the interaction of the
solar wind and cometary ions during two different time periods in the Rosetta
mission. Methods: We compared both the integrated ion moments (density,
velocity, and momentum flux) and the velocity distribution functions for two
days, four months apart. The velocity distribution functions were projected
into a coordinate system dependent on the magnetic field direction and averaged
over three hours. Results: The first case shows highly scattered H+ in both ion
moments and velocity distribution function. The He2+ ions are somewhat
scattered, but less so, and appear more like those of H2O+ pickup ions. The
second case shows characteristic evidence of mass-loading, where the solar wind
species are deflected, but the velocity distribution function is not
significantly changed. Conclusions: The distributions of H+ in the first case,
when compared to He2+ and H2O+ pickup ions, are indicative of a narrow
cometosheath on the scale of the H+ gyroradius. Thus, He2+ and H2O+, with
larger gyroradii, are largely able to pass through this cometosheath. An
examination of the momentum flux tensor suggests that all species in the first
case have a significant non-gyrotropic momentum flux component that is higher
than that of the second mass-loaded case. Mass loading is not a sufficient
explanation for the distribution functions and momentum flux tensor in the
first case, and so we assume this is evidence of bow shock formation.Comment: 14 pages, 9 figures, 3 tables, 2 video
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