6,694 research outputs found
Lith genes and genetic analysis of cholesterol gallstone formation
No full textIn 1964, Tepperman and colleagues9 first established a mouse model of cholesterol gallstones by feeding a special lithogenic diet containing 1% cholesterol and 0.5% cholic acid. Later, Fujihira and colleagues10 found that at 8 weeks on the lithogenic diet, gallstone prevalence rates varied from 0% to 100% in 7 strains of mic
UiO-66-NH-(AO) MOFs with a New Ligand BDC-NH-(CN) for Efficient Extraction of Uranium from Seawater
No full textMetal–organic
frameworks (MOFs) with a high surface area
and excellent stability are potential candidates for uranium (U) adsorption.
Amidoxime (AO) is the most widely used functional group to extract
U, which is usually introduced into MOFs by two-step post-synthetic
methods (PSMs). Herein, MOF UiO-66-NH-(AO) was obtained by a one-step
PSM with amidoximation from UiO-66-NH-(CN), which was synthesized
by a new organic ligand of 2-cyano-terephthalic acid and whose morphology
was octahedron and could be well controlled with the new ligand. The
one-step PSM can greatly maintain the octahedron of the MOFs. What
is more, UiO-66-NH-(AO) showed good adsorption performance for U,
the adsorption equilibrium was obtained within 1500 min, and the adsorption
capacity of U was calculated to be 134.1 mg/g according to the Langmuir
model. It also had excellent selectivity for U in the presence of
high concentrations of vanadium (V), ferrum (Fe), magnesium (Mg),
calcium (Ca), and zirconium (Zr). The adsorption capacity of U in
natural seawater was determined to be 5.2 mg/g within 8 days. The
recyclability of UiO-66-NH-(AO) in simulated seawater was demonstrated
for at least four adsorption/desorption cycles. The binding mechanism
was investigated by the extended X-ray absorption fine structure spectroscopy,
revealing that U binding occurs in a fashion η2 motif.
This study provides a reliable idea for the modification of MOFs and
the potential for MOF-based materials to extract U from seawater
Dehydrogenation of the NH−NH Bond Triggered by Potassium tert-Butoxide in Liquid Ammonia
No full textA novel strategy for the dehydrogenation of NH-NH bond is disclosed using potassium t-butoxide (tBuOK) in liquid NH3 under air (O2) at room temperature. Its synthetic values are well demonstrated via highly efficient synthesis of aromatic azo compounds (up to 100% yield, 3 min), heterocyclic azo compounds, and dehydrazination of phenylhydrazine. The broad application of this strategy and its benefit to chemical biology is proved by a novel, convenient, one-pot and efficient synthesis of aliphatic diazirines, which are important photoreactive agents for photoaffinity labeling
A narrative-based collaborative writing tool for coherent technical documents
No full textOne important feature of an effective document that makes it easy to read and understand is known as coherence. Technical documents produced collaboratively are often incoherent due to a lack of group consensus and misaligned contributions by the individual authors. However, current document planning techniques and writing tools do not provide explicit support for improving coherence. The goal of this research, therefore, is to develop and evaluate a new technique and tool that helps teams of authors to structure coherent technical documents. The coherence of a document can be attributed to the story (or narrative) it conveys to the reader. If this story is consistent and coherent, the same can be said about the document. A discourse theory such as Rhetorical Structure Theory (RST) that has been developed by linguists helps further to analyse and improve a narrative. RST explains the coherence of a text by virtue of relationships (such as “paragraph A justifies paragraph B”) between parts of the text. This research has combined the ideas from these parallel strands of research to develop a new document planning technique called narrative-based writing. The method involves writing down an explicit précis of the story (called a document narrative or DN) and then analysing it using RST. The DN and RST analysis are then used to structure the eventual document. To extend the usability of narrative-based writing to geographically-dispersed authors, I have designed and implemented a collaborative tool that allows co-authors to edit, analyse and review DNs. The thorough design for the tool uses a combination of three models (conceptual, business process and functional) culminating in a set of functions that enable collaborative narrative-based writing. This dissertation discusses how, in the future, these functions could be incorporated in existing collaborative writing tools. Implementing this tool, albeit in its current prototypic state, has been invaluable in understanding the complexities of modelling and manipulating DNs and RST structures. Initial investigations using the new technique and tool have been positive, encouraging me to continue the research and evaluation in this field
Evaluatie suppleties Noord-Holland en Texel
No full textNote: NH-93.ANV002a.pdf bevat het hoofdrapport en NH-93.ANV002b.pdf bevat alle bijlagen. ----- De minister van Verkeer en Waterstaat heeft de kamer een interim-nota kustverdediging in 1993 toegezegd, waarin het kustverdedigingsbeleid wordt geëvalueerd. Een onderdeel van deze evaluatie is de evaluatie van de zandsuppleties. Om deze evaluatie uit te voeren is de werkgroep EVAZAND, onder leiding van de Dienst Getijdewateren, ingesteld. De evaluatie beperkt zich in principe tot de morfologische aspecten en is hoofdzakelijk gericht op het bepalen van de doelmatigheid of de effectiviteit van zandsuppleties. Omdat suppleties van 1990 of later zich vanwege de korte levensduur nauwelijks lenen voor evaluatie is een selectie gemaakt uit de suppleties van vóór 1990. Deze nota dient als de bijdrage van de Directie Noord-Holland aan het project EVAZAND en bevat de evaluatie van alle grote zandsuppleties van Noord-Holland en Texel van vóór 1990.EVAZAN
Influence of everolimus on cylcopsorine Neoral pharmacokinetics in Chinese de Novo cardiac transplant recipients
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