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Textbooks represent a significant portion of the overall cost of higher education in the United States. The burden of these costs is typically shouldered by students, those who support them, and the taxpayers who fund the grants and student loans which pay for textbooks. Open educational resources (OER) provide students a way to receive high-quality learning materials at little or no cost to students. We report on the cost savings achieved by students at eight colleges when these colleges began utilizing OER in place of traditional commercial textbooks.

Analysis of interviews with 41 service providers (20 deaf, 21 hearing) who worked together at three British organizations found deaf and hearing individuals had differing perspectives on the integrated working experience and the use of sign language in the work setting. Deaf/hearing relations were perceived as largely person-centered by deaf individuals but as largely language-centered by hearing individuals. (Contains references.) (Author/DB)

Diet manipulation is a promising way for reducing phosphorus (P) content in manure and subsequently in surface water. The objective of this study is to clarify the effects of dietary fiber content on P distribution in fresh and stored liquid hog manure. Ten, 25 L liquid manure storage tanks were constructed and operated to simulate farm-based manure storage lagoons. Fifteen pigs were randomly grouped into three pens and the pigs in each pen were fed with a diet of different fiber contents (12%, 16%, and 21%). For 20 weeks, one litre of liquid manure from each pen was fed to each storage tank once a week with 3 replicate storage tanks per diet treatment. The samples of fresh and stored manure, each representing a diet treatment, were analyzed for P distribution along the fractions of dissolved organic, dissolved inorganic, particulate organic, and particulate inorganic. The results showed that fresh manure derived from the high fiber diet contained lower total P concentrations. Of the four fractions of total P, particulate organic P and particulate inorganic P composed 95.3% to 97.5% of total P in the fresh manure. After storage, the dissolved P concentration increased from around 25 ppm to 30-60 ppm. Inorganic P was the main fraction in dissolved P and composed 80% of the dissolved P in stored manure. The dissolved inorganic P, and therefore the total dissolved P were speculated to increase with manure storage time, indicating microbial activity through digestion. It was concluded that a higher fiber diet yielding manure with higher fiber content resulted in enhanced anaerobic degradation during manure storage. This, in return might promote the destruction of organic materials, resulting in the release of P and subsequent formation of inorganic dissolved P. Key words: hog manure, phosphorus, liquid manure storage, fiber content, diet manipulation. La modification du regime alimentaire est une maniere prometteuse de reduire le contenu en phosphore (P) du lisier et, par la suite, de l'eau de surface. L'objectif de la presente etude est de clarifier les effets du contenu en fibres alimentaires sur la distribution du P dans le lisier de porc liquide frais et entrepose. Dix reservoirs d'entreposage de lisier liquide de 25 L ont ete construits et operes de maniere a simuler les lagons de retenue du lisier sur les fermes. Quinze porcs ont ete regroupes aleatoirement en trois enclos et les porcs de chaque enclos ont recu une alimentation presentant differents contenus en fibres (12%, 16% et 21%). Une fois par semaine pendant 20 semaines, un litre de lisier liquide de chaque enclos a ete transfere dans chaque reservoir d'entreposage avec trois reservoirs d'entreposage en replica pour chaque traitement alimentaire. La distribution de P des echantillons de lisier frais et entrepose, chacun representant un traitement alimentaire, a ete analysee, de meme que les fractions de matiere organique dissoute, de matiere inorganique dissoute, de particules organiques et de particules inorganiques. Les resultats montrent que le lisier frais provenant du regime alimentaire a haute teneur en fibres contenait de plus faibles concentrations en P total. Des quatre fractions de P total, le P des particules organiques et le P des particules inorganiques representaient respectivement 95,3% et 97,5% du P total dans le lisier frais. Apres entreposage, la concentration en P dissous passait d'environ 25 ppm a 30-60 ppm. Le P inorganique representait la fraction principale en P dissous et comptait pour 80% du P dissous dans le lisier entrepose. Il a ete presume que le P inorganique dissous, donc le P dissous total, augmentait avec le temps d'entreposage du lisier, indiquant une activite microbienne par digestion. Il a ete conclu qu'un regime alimentaire plus haut en fibres donnait un lisier contenant plus de fibres, encourageant une degradation anaerobie accrue durant l'entreposage du lisier. Cela pourrait, en retour, faciliter la destruction des matieres organiques, entramant la liberation du P puis la formation subsequente de P inorganique dissous. [Traduit par la Redaction] Mots-cles: lisier de porc, phosphore, entreposage de lisier liquide, contenu en fibres, manipulation du regime alimentaire., Introduction Eutrophication, a result of phosphorus accumulation in soil and water, is a well-known environmental issue around the world, and manure produced from agricultural industry is considered to be one [...]