999 resultados para Eugene Sandow


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The enantiodivergent formal syntheses of both enantiomers of aspercyclide C is accomplished. Starting from L-(+)-tartaric acid, the key protected allylic alcohol, (3R,4R)-4-(methoxy-methoxy) non-1-en-3-ol is prepared, and is then elaborated into both enantiomers of 3-(4-methoxybenzyl)oxy]non-1-en-4-ol via Mitsunobu inversion. Esterification with a known biaryl acid, followed by ring-closing metathesis and deprotection completes the syntheses.

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The finding that peptides containing -amino acid residues give rise to folding patterns hitherto unobserved in -amino acid peptides[1] has stimulated considerable interest in the conformational properties of peptides built from , and residues,[2] as the introduction of additional methylene (CH2) units into peptide chains provides further degrees of conformational freedom.

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Despite a significant growth in food production over the past half-century, one of the most important challenges facing society today is how to feed an expected population of some nine billion by the middle of the 20th century. To meet the expected demand for food without significant increases in prices, it has been estimated that we need to produce 70-100 per cent more food, in light of the growing impacts of climate change, concerns over energy security, regional dietary shifts and the Millennium Development target of halving world poverty and hunger by 2015. The goal for the agricultural sector is no longer simply to maximize productivity, but to optimize across a far more complex landscape of production, rural development, environmental, social justice and food consumption outcomes. However, there remain significant challenges to developing national and international policies that support the wide emergence of more sustainable forms of land use and efficient agricultural production. The lack of information flow between scientists, practitioners and policy makers is known to exacerbate the difficulties, despite increased emphasis upon evidence-based policy. In this paper, we seek to improve dialogue and understanding between agricultural research and policy by identifying the 100 most important questions for global agriculture. These have been compiled using a horizon-scanning approach with leading experts and representatives of major agricultural organizations worldwide. The aim is to use sound scientific evidence to inform decision making and guide policy makers in the future direction of agricultural research priorities and policy support. If addressed, we anticipate that these questions will have a significant impact on global agricultural practices worldwide, while improving the synergy between agricultural policy, practice and research. This research forms part of the UK Government's Foresight Global Food and Farming Futures project.

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An enantiospecific total synthesis of indole alkaloids eburnamonine, aspidospermidine and quebrachamine is described from lactic acid. Synthesis of all three alkaloids is accomplished from a single chiral building block. Johnson-Claisen rearrangement of a chiral allyl alcohol is the main feature for the installation of the required quaternary centre.

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The total synthesis of new indole alkaloids henrycinol A and B were accomplished starting from L-tryptophan methyl ester. The key step is a stereochemically flexible Pictet-Spengler reaction governed by the presence or absence of an N-allyl group in the tryptophan precursor. The natural products henrycinol A and B were synthesized in good overall yield in eight and nine steps, respectively. (C) 2014 Elsevier Ltd. All rights reserved.

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A facile general route for the synthesis of azepino4,5-b]indolones is presented. The strategy involves a Bronsted acid assisted intramolecular cyclization of unsaturated tryptamides. The methodology developed has been applied to the synthesis of the ABCD tetracyclic core of the natural product tronocarpine.

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Background: In the post-genomic era where sequences are being determined at a rapid rate, we are highly reliant on computational methods for their tentative biochemical characterization. The Pfam database currently contains 3,786 families corresponding to ``Domains of Unknown Function'' (DUF) or ``Uncharacterized Protein Family'' (UPF), of which 3,087 families have no reported three-dimensional structure, constituting almost one-fourth of the known protein families in search for both structure and function. Results: We applied a `computational structural genomics' approach using five state-of-the-art remote similarity detection methods to detect the relationship between uncharacterized DUFs and domain families of known structures. The association with a structural domain family could serve as a start point in elucidating the function of a DUF. Amongst these five methods, searches in SCOP-NrichD database have been applied for the first time. Predictions were classified into high, medium and low-confidence based on the consensus of results from various approaches and also annotated with enzyme and Gene ontology terms. 614 uncharacterized DUFs could be associated with a known structural domain, of which high confidence predictions, involving at least four methods, were made for 54 families. These structure-function relationships for the 614 DUF families can be accessed on-line at http://proline.biochem.iisc.ernet.in/RHD_DUFS/. For potential enzymes in this set, we assessed their compatibility with the associated fold and performed detailed structural and functional annotation by examining alignments and extent of conservation of functional residues. Detailed discussion is provided for interesting assignments for DUF3050, DUF1636, DUF1572, DUF2092 and DUF659. Conclusions: This study provides insights into the structure and potential function for nearly 20 % of the DUFs. Use of different computational approaches enables us to reliably recognize distant relationships, especially when they converge to a common assignment because the methods are often complementary. We observe that while pointers to the structural domain can offer the right clues to the function of a protein, recognition of its precise functional role is still `non-trivial' with many DUF domains conserving only some of the critical residues. It is not clear whether these are functional vestiges or instances involving alternate substrates and interacting partners. Reviewers: This article was reviewed by Drs Eugene Koonin, Frank Eisenhaber and Srikrishna Subramanian.

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Report seeks to address following questions: 1. Where within Lee County are surface supplies of water located? 2. What are the variations in this supply? 3. What can be done to provide better answers to questions 1 and 2 than are available at the present time? (PDF contains 76 pages.)

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Angler creel surveys and economic impact models were used to evaluate potential expansion of aquatic vegetation in Lakes Murray and Moultrie, South Carolina. (PDF contains 4 pages.)

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Investigation of Ctenophores in the Chesapeake Bay area, includes some aspects of their life history, growth, reproduction, feeding and food habits, abundance and distribution. the purpose of the entire project is to supplement and add to the biological knowledge and understanding of ctenophores as a group and of the several individual species found int he area to be studied. Includes possible factors involved and implications also being looked at. (PDF contains 33 pages)

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Investigation on the effects of explosive shock on marine life. Necessary that the "commercial" effects, the actual damage to commercially important stocks of fish and shellfish, be evaluated. Equally important are the "biological" effects, the immediate physical effects of shock waves on animals and the indirect effects on future stocks. Indirect effects might include the diversion of migratory stocks from an area, or actual damage to the habitat, rendering it unfit for sedentary or non-migratory native species. Interruption of the food chains in an area by destruction of forge forms or vegetation. (PDF contains 43 pages)

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Information on the biology and fisheries of cobia, Rachycentron canadum, is compiled and reviewed in the FAD species synopsis style. Topics include taxonomy, morphology, distribution, reproduction, pre-adult and adult stages, food, growth, migration, population characteristics, and various aspects of exploitation. Data and information were obtained from unpublished as well as published sources. Cobia, the only species in the family Rachycentridae, is a migratory pelagic fish that occurs in tropical and subtropical seas of the world, except in the central and eastern Pacific Ocean. In the western Atlantic Ocean, spawning occurs during the warm months. Eggs and larvae are planktonic. Females grow faster than males: at 1 year, females are 36 cm FL and 0.4 kg; at 4 years, 99 cm and 11 kg; and at 8 years, 137 cm and 31 kg. Comparable data for males are: at 1 year, 31 cm and 0.3 kg; 4 years, 82 cm and 6 kg; and 8 years, 108 cm and 15 kg. Sexual maturity is attained by males at about 52 cm FL in their second year and by females at about 70 cm in their third year. Fecundity for females 100-125 cm FL varies from 1.9 to 5.4 million eggs. Cobia favor crustaceans for food, but will feed on other invertebrates and fishes as well. They attain a maximum size of over 60 kg. Cobia are fished both commercially and recreationally. Commercially, they are usually caught incidentally in both hook-and-Iine and net fISheries. In the United States, which ranks behind Pakistan, Mexico, and the Philippines in commercial production of cobia, recreational landings exceed commercial landings by more than ten-fold. (PDF file contains 32 pages.)

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A small isolated tide pool was studied quite intensively over a period on one month. A oensus of all animals present was taken, and a population record kept daily for the month. Fluctuations in the numbers of individuals were noted, and reasons for these fluctuations sought. The behavior and feeding habits of the various animals were noted, and an attempt was made to relate the animals to their environment. This is a student paper done for a University of California Berkeley Zoology class. Since UCB didn't have its own marine lab at the time, it rented space at Hopkins Marine Station where this work was done. Gene Haderlie went on to earn his Ph.D. from Berkeley and later became a Professor at the Naval Post Graduate School in Monterey. (PDF contains 22 pages)

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Ten limpets (4 Acmaea digitalis , 4 Acmaea scutum, 1 Acmaea limatula, and 1 Lottia gigantea) were marked and their movements observed over a thirteen day period. Recordings of positions were made on a map, and the path of each was drawn on the map from day to day. Acmaea digitalis showed the greatest range, mostly in a vertical direction, and moved usually at night during high tide. Acmaea scutum showed a more limited range in a horizontal direction, and moved both day and night during high tide. Acmaea limatula had a horizontal range similar to A. scutum,, but exhibited no movement during the day time. Lottia gigantea had the most restricted range of any limpet studied, and moved only at night during high tide. This is a student paper done for a University of California Berkeley Zoology class. Since UCB didn't have its own marine lab at the time, it rented space at Hopkins Marine Station where this work was done. Gene Haderlie went on to earn his Ph.D. from Berkeley and later became a Professor at the Naval Post Graduate School in Monterey. (PDF contains 23 pages)