73 research outputs found
From Baking a Cake to Solving the Schrodinger Equation
The primary emphasis of this study has been to explain how modifying a cake
recipe by changing either the dimensions of the cake or the amount of cake
batter alters the baking time. Restricting our consideration to the genoise,
one of the basic cakes of classic French cuisine, we have obtained a
semi-empirical formula for its baking time as a function of oven temperature,
initial temperature of the cake batter, and dimensions of the unbaked cake. The
formula, which is based on the Diffusion equation, has three adjustable
parameters whose values are estimated from data obtained by baking genoises in
cylindrical pans of various diameters. The resulting formula for the baking
time exhibits the scaling behavior typical of diffusion processes, i.e. the
baking time is proportional to the (characteristic length scale)^2 of the cake.
It also takes account of evaporation of moisture at the top surface of the
cake, which appears to be a dominant factor affecting the baking time of a
cake. In solving this problem we have obtained solutions of the Diffusion
equation which are interpreted naturally and straightforwardly in the context
of heat transfer; however, when interpreted in the context of the Schrodinger
equation, they are somewhat peculiar. The solutions describe a system whose
mass assumes different values in two different regions of space. Furthermore,
the solutions exhibit characteristics similar to the evanescent modes
associated with light waves propagating in a wave guide. When we consider the
Schrodinger equation as a non-relativistic limit of the Klein-Gordon equation
so that it includes a mass term, these are no longer solutions.Comment: 23 pages, 10 Postscript figure
Psychological Aspects of Slaughter: Reactions of College Students to Killing and Butchering Cattle and Hogs
This study examined college students\u27 reactions to slaughtering cattle and hogs as part of their jobs on a college work crew. The 27 students were surveyed on attitudes containing items toward slaughtering animals and toward different uses of animals. Nineteen were later interviewed. Some aspects of slaughtering were reported to be more bothersome than others. There was a relationship between the subjects\u27 experience in slaughtering, general attitudes toward various uses of animals, and their responses to several of the items on the questionnaire. The perceived benefits of the slaughtering experience and the justification for killing domestic animals for food are also discussed
Psychological Aspects of Slaughter: Reactions of College Students to Killing and Butchering Cattle and Hogs
This study examined the reactions of college students involved in slaughtering cattle and hogs as part of their jobs on a college work crew. The 27 students were surveyed on attitudes containing items toward slaughtering animals and toward different uses of animals. Nineteen were later interviewed. Some aspects of slaughtering were reported to be more bothersome than others. There was a relationship between the amount of experience of the subjects in slaughtering and also their general attitudes toward various uses of animals and their responses to several of the items on the questionnaire. The perceived benefits of the slaughtering experience and the justifications given for the killing of domestic animals for food are also discussed
A hidden fire: Russian and Japanese cultural encounters 1868-1926
Publisher's version/PDFReviews the book 'A Hidden Fire: Russian and Japanese Cultural Encounters 1868-1926,' by J. Thomas Rimer
Compositional Data Analysis is necessary for simulating and analyzing RNA-Seq data
*Seq techniques (e.g. RNA-Seq) generate compositional datasets, i.e. the number of fragments sequenced is not proportional to the total RNA present. Thus, datasets carry only relative information, even though absolute RNA copy numbers are often of interest. Current normalization methods assume most features are not changing, which can lead to misleading conclusions when there are large shifts. However, there are few real datasets and no simulation protocols currently available that can directly benchmark methods when such large shifts occur. We present absSimSeq, an R package that simulates compositional data in the form of RNA-Seq reads. We tested several tools used for RNA-Seq differential analysis: sleuth, DESeq2, edgeR, limma, sleuth and ALDEx2 (which explicitly takes a compositional approach). For these tools, we compared their standard normalization to either “compositional normalization”, which uses log-ratios to anchor the data on a set of negative control features, or RUVSeq, another tool that directly uses negative control features. We show that common normalizations result in reduced performance with current methods when there is a large change in the total RNA per cell. Performance improves when spike-ins are included and used by a compositional approach, even if the spike-ins have substantial variation. In contrast, RUVSeq, which normalizes count data rather than compositional data, has poor performance. Further, we show that previous criticisms of spike-ins did not take into account the compositional nature of the data. We conclude that absSimSeq can generate more representative datasets for testing performance, and that spike-ins should be more broadly used in a compositional manner to minimize misleading conclusions from differential analyses
BREEDING BEHAVIOR OF THE GRAY-BREASTED FLYCATCHER (LATHROTRICCUS GRISEIPECTUS) IN SOUTHWESTERN ECUADOR
Abstract ∙ Little is known about the nesting behavior of the Gray-breasted Flycatcher (Lathrotriccus griseipectus), a species listed as Vulnerable by the International Union for Conservation of Nature. In order to add fundamental information on the life history of this species, we recorded parental behavior at a nest in February–March 2010 in the Jorupe Reserve in southwestern Ecuador. Recordings were made on a tripod-mounted video camera and took place during part of the incubation and nestling stages. Both adults provisioned nestlings. We recorded 7.1 feeds per nestling-hour, with the highest average provisioning rates occurring from 12:00–13:00 h. Nestlings produced an average of 0.8 fecal sacs per nestling-hour. Nestlings fledged in quick succession shortly before 12:00 h on nestling-day 14.Resumen ∙ El cuidado parental del Mosquero Pechigrís (Lathrotriccus griseipectus) en el suroeste del Ecuador La biología reproductiva del Mosquero Pechigrís (Lathrotriccus griseipectus), una especie catalogada como “Vulnerable” por la Unión Internacional para la Conservación de la Naturaleza, es poco conocida. Con el fin de añadir datos básicos sobre la historia de vida del Mosquero Pechigrís, utilizamos una cámara de video para realizar observaciones de un nido ubicado en la Reserva Jorupe en el suroeste de Ecuador, entre febrero y marzo de 2010. Las grabaciones tuvieron lugar durante parte de las etapas de incubación y polluelo. Ambos adultos aprovisionaron polluelos. Registramos 7.1 alimentaciones de polluelo por hora, siendo las tasas de aprovisionamiento más altas de 12:00–13:00 h. Los polluelos produjeron un promedio de 0.8 sacos fecales por hora y polluelo. Los polluelos emplumaron en rápida sucesión poco antes del mediodía 14 días luego de la eclosión
Compositional Data Analysis is necessary for simulating and analyzing RNA-Seq data
*Seq techniques (e.g. RNA-Seq) generate compositional datasets, i.e. the number of fragments sequenced is not proportional to the total RNA present. Thus, datasets carry only relative information, even though absolute RNA copy numbers are often of interest. Current normalization methods assume most features are not changing, which can lead to misleading conclusions when there are large shifts. However, there are few real datasets and no simulation protocols currently available that can directly benchmark methods when such large shifts occur. We present absSimSeq, an R package that simulates compositional data in the form of RNA-Seq reads. We tested several tools used for RNA-Seq differential analysis: sleuth, DESeq2, edgeR, limma, sleuth and ALDEx2 (which explicitly takes a compositional approach). For these tools, we compared their standard normalization to either “compositional normalization”, which uses log-ratios to anchor the data on a set of negative control features, or RUVSeq, another tool that directly uses negative control features. We show that common normalizations result in reduced performance with current methods when there is a large change in the total RNA per cell. Performance improves when spike-ins are included and used by a compositional approach, even if the spike-ins have substantial variation. In contrast, RUVSeq, which normalizes count data rather than compositional data, has poor performance. Further, we show that previous criticisms of spike-ins did not take into account the compositional nature of the data. We conclude that absSimSeq can generate more representative datasets for testing performance, and that spike-ins should be more broadly used in a compositional manner to minimize misleading conclusions from differential analyses
A História da Alimentação: balizas historiográficas
Os M. pretenderam traçar um quadro da História da Alimentação, não como um novo ramo epistemológico da disciplina, mas como um campo em desenvolvimento de práticas e atividades especializadas, incluindo pesquisa, formação, publicações, associações, encontros acadêmicos, etc. Um breve relato das condições em que tal campo se assentou faz-se preceder de um panorama dos estudos de alimentação e temas correia tos, em geral, segundo cinco abardagens Ia biológica, a econômica, a social, a cultural e a filosófica!, assim como da identificação das contribuições mais relevantes da Antropologia, Arqueologia, Sociologia e Geografia. A fim de comentar a multiforme e volumosa bibliografia histórica, foi ela organizada segundo critérios morfológicos. A seguir, alguns tópicos importantes mereceram tratamento à parte: a fome, o alimento e o domínio religioso, as descobertas européias e a difusão mundial de alimentos, gosto e gastronomia. O artigo se encerra com um rápido balanço crítico da historiografia brasileira sobre o tema
Q&A: Harold McGee, the curious cook
<p>Abstract</p> <p>Harold McGee, author of best-selling book, <it>On Food And Cooking</it>, talks to <it>Flavour</it> about minerality, academia and molecular gastronomy.</p
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